Li Li

Li Li, Christian J. Stoeckert, Jr., and David S. Roos1 Departments of Biology and Genetics, Center for Bioinformatics, and Genomics Institute, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA

CD4+CD25+ regulatory T cells (Treg) are instrumental in the maintenance of immunological tolerance. One critical question is whether Treg can only be generated in the thymus or can differentiate from peripheral CD4+CD25- naive T cells. In this paper, we present novel evidence that conversion of naive peripheral CD4+CD25- T cells into anergic/suppressor cells that are CD25+, CD45RB-/low and intracellular CTLA-4+ can be achieved through costimulation with T cell receptors (TCRs) and transforming growth factor beta (TGF-beta). Although transcription factor Foxp3 has been shown recently to be associated with the development of Treg, the physiological inducers for Foxp3 gene expression remain a mystery. TGF-beta induced Foxp3 gene expression in TCR-challenged CD4+CD25- naive T cells, which mediated their transition toward a regulatory T cell phenotype with potent immunosuppressive potential. These converted anergic/suppressor cells are not only unresponsive to TCR stimulation and produce neither T helper cell 1 nor T helper cell 2 cytokines but they also express TGF-beta and inhibit normal T cell proliferation in vitro. More importantly, in an ovalbumin peptide TCR transgenic adoptive transfer model, TGF-beta-converted transgenic CD4+CD25+ suppressor cells proliferated in response to immunization and inhibited antigen-specific naive CD4+ T cell expansion in vivo. Finally, in a murine asthma model, coadministration of these TGF-beta-induced suppressor T cells prevented house dust mite-induced allergic pathogenesis in lungs.

Background The coronavirus disease 2019 (COVID-19) outbreak is evolving rapidly worldwide. Objective To evaluate the risk of serious adverse outcomes in patients with COVID-19 by stratifying the comorbidity status. Methods We analysed data from 1590 laboratory confirmed hospitalised patients from 575 hospitals in 31 provinces/autonomous regions/provincial municipalities across mainland China between 11 December 2019 and 31 January 2020. We analysed the composite end-points, which consisted of admission to an intensive care unit, invasive ventilation or death. The risk of reaching the composite end-points was compared according to the presence and number of comorbidities. Results The mean age was 48.9 years and 686 (42.7%) patients were female. Severe cases accounted for 16.0% of the study population. 131 (8.2%) patients reached the composite end-points. 399 (25.1%) reported having at least one comorbidity. The most prevalent comorbidity was hypertension (16.9%), followed by diabetes (8.2%). 130 (8.2%) patients reported having two or more comorbidities. After adjusting for age and smoking status, COPD (HR (95% CI) 2.681 (1.424–5.048)), diabetes (1.59 (1.03–2.45)), hypertension (1.58 (1.07–2.32)) and malignancy (3.50 (1.60–7.64)) were risk factors of reaching the composite end-points. The hazard ratio (95% CI) was 1.79 (1.16–2.77) among patients with at least one comorbidity and 2.59 (1.61–4.17) among patients with two or more comorbidities. Conclusion Among laboratory confirmed cases of COVID-19, patients with any comorbidity yielded poorer clinical outcomes than those without. A greater number of comorbidities also correlated with poorer clinical outcomes.

The Hippo pathway plays a key role in organ size control by regulating cell proliferation and apoptosis in Drosophila. Although recent genetic studies have shown that the Hippo pathway is regulated by the NF2 and Fat tumor suppressors, the physiological regulations of this pathway are unknown. Here we show that in mammalian cells, the transcription coactivator YAP (Yes-associated protein), is inhibited by cell density via the Hippo pathway. Phosphorylation by the Lats tumor suppressor kinase leads to cytoplasmic translocation and inactivation of the YAP oncoprotein. Furthermore, attenuation of this phosphorylation of YAP or Yorkie (Yki), the Drosophila homolog of YAP, potentiates their growth-promoting function in vivo. Moreover, YAP overexpression regulates gene expression in a manner opposite to cell density, and is able to overcome cell contact inhibition. Inhibition of YAP function restores contact inhibition in a human cancer cell line bearing deletion of Salvador (Sav), a Hippo pathway component. Interestingly, we observed that YAP protein is elevated and nuclear localized in some human liver and prostate cancers. Our observations demonstrate that YAP plays a key role in the Hippo pathway to control cell proliferation in response to cell contact.

The YAP transcription coactivator has been implicated as an oncogene and is amplified in human cancers. Recent studies have established that YAP is phosphorylated and inhibited by the Hippo tumor suppressor pathway. Here we demonstrate that the TEAD family transcription factors are essential in mediating YAP-dependent gene expression. TEAD is also required for YAP-induced cell growth, oncogenic transformation, and epithelial-mesenchymal transition. CTGF is identified as a direct YAP target gene important for cell growth. Moreover, the functional relationship between YAP and TEAD is conserved in Drosophila Yki (the YAP homolog) and Scalloped (the TEAD homolog). Our study reveals TEAD as a new component in the Hippo pathway playing essential roles in mediating biological functions of YAP.

Based on the understanding of the ORR catalytic mechanism, advanced Pt-based and Pt-free catalysts have been explored.

The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa.

Currently, there are no approved specific antiviral agents for novel coronavirus disease 2019 (COVID-19). In this study, 10 severe patients confirmed by real-time viral RNA test were enrolled prospectively. One dose of 200 mL of convalescent plasma (CP) derived from recently recovered donors with the neutralizing antibody titers above 1:640 was transfused to the patients as an addition to maximal supportive care and antiviral agents. The primary endpoint was the safety of CP transfusion. The second endpoints were the improvement of clinical symptoms and laboratory parameters within 3 d after CP transfusion. The median time from onset of illness to CP transfusion was 16.5 d. After CP transfusion, the level of neutralizing antibody increased rapidly up to 1:640 in five cases, while that of the other four cases maintained at a high level (1:640). The clinical symptoms were significantly improved along with increase of oxyhemoglobin saturation within 3 d. Several parameters tended to improve as compared to pretransfusion, including increased lymphocyte counts (0.65 × 10 9 /L vs. 0.76 × 10 9 /L) and decreased C-reactive protein (55.98 mg/L vs. 18.13 mg/L). Radiological examinations showed varying degrees of absorption of lung lesions within 7 d. The viral load was undetectable after transfusion in seven patients who had previous viremia. No severe adverse effects were observed. This study showed CP therapy was well tolerated and could potentially improve the clinical outcomes through neutralizing viremia in severe COVID-19 cases. The optimal dose and time point, as well as the clinical benefit of CP therapy, needs further investigation in larger well-controlled trials.

Understanding the origin of high activity of Fe–N–C electrocatalysts in oxygen reduction reaction (ORR) is critical but still challenging for developing efficient sustainable nonprecious metal catalysts in fuel cells and metal–air batteries. Herein, we developed a new highly active Fe–N–C ORR catalyst containing Fe–Nx coordination sites and Fe/Fe3C nanocrystals (Fe@C-FeNC), and revealed the origin of its activity by intensively investigating the composition and the structure of the catalyst and their correlations with the electrochemical performance. The detailed analyses unambiguously confirmed the coexistence of Fe/Fe3C nanocrystals and Fe–Nx in the best catalyst. A series of designed experiments disclosed that (1) N-doped carbon substrate, Fe/Fe3C nanocrystals or Fe–Nx themselves did not deliver the high activity; (2) the catalysts with both Fe/Fe3C nanocrystals and Fe–Nx exhibited the high activity; (3) the higher content of Fe–Nx gave the higher activity; (4) the removal of Fe/Fe3C nanocrystals severely degraded the activity; (5) the blocking of Fe–Nx downgraded the activity and the recovery of the blocked Fe–Nx recovered the activity. These facts supported that the high ORR activity of the Fe@C-FeNC electrocatalysts should be ascribed to that Fe/Fe3C nanocrystals boost the activity of Fe–Nx. The coexistence of high content of Fe–Nx and sufficient metallic iron nanoparticles is essential for the high ORR activity. DFT calculation corroborated this conclusion by indicating that the interaction between metallic iron and Fe–N4 coordination structure favored the adsorption of oxygen molecule. These new findings open an avenue for the rational design and bottom-up synthesis of low-cost highly active ORR electrocatalysts.

Gaussian boson sampling exploits squeezed states to provide a highly efficient way to demonstrate quantum computational advantage. We perform experiments with 50 input single-mode squeezed states with high indistinguishability and squeezing parameters, which are fed into a 100-mode ultralow-loss interferometer with full connectivity and random transformation, and sampled using 100 high-efficiency single-photon detectors. The whole optical set-up is phase-locked to maintain a high coherence between the superposition of all photon number states. We observe up to 76 output photon-clicks, which yield an output state space dimension of $10^{30}$ and a sampling rate that is $10^{14}$ faster than using the state-of-the-art simulation strategy and supercomputers. The obtained samples are validated against various hypotheses including using thermal states, distinguishable photons, and uniform distribution.

Jun Wang and colleagues report the genome sequence of the cucumber. The cucumber genome is the seventh plant genome sequence to be reported and was assembled with a combination of traditional Sanger and next-generation sequencing methods. Cucumber is an economically important crop as well as a model system for sex determination studies and plant vascular biology. Here we report the draft genome sequence of Cucumis sativus var. sativus L., assembled using a novel combination of traditional Sanger and next-generation Illumina GA sequencing technologies to obtain 72.2-fold genome coverage. The absence of recent whole-genome duplication, along with the presence of few tandem duplications, explains the small number of genes in the cucumber. Our study establishes that five of the cucumber's seven chromosomes arose from fusions of ten ancestral chromosomes after divergence from Cucumis melo. The sequenced cucumber genome affords insight into traits such as its sex expression, disease resistance, biosynthesis of cucurbitacin and 'fresh green' odor. We also identify 686 gene clusters related to phloem function. The cucumber genome provides a valuable resource for developing elite cultivars and for studying the evolution and function of the plant vascular system.

TORC1 (target of rapamycin complex 1) has a crucial role in the regulation of cell growth and size. A wide range of signals, including amino acids, is known to activate TORC1. Here, we report the identification of Rag GTPases as activators of TORC1 in response to amino acid signals. Knockdown of Rag gene expression suppressed the stimulatory effect of amino acids on TORC1 in Drosophila melanogaster S2 cells. Expression of constitutively active (GTP-bound) Rag in mammalian cells activated TORC1 in the absence of amino acids, whereas expression of dominant-negative Rag blocked the stimulatory effects of amino acids on TORC1. Genetic studies in Drosophila also show that Rag GTPases regulate cell growth, autophagy and animal viability during starvation. Our studies establish a function of Rag GTPases in TORC1 activation in response to amino acid signals.

The Yes-associated protein (YAP) transcription coactivator is a key regulator of organ size and a candidate human oncogene. YAP is inhibited by the Hippo pathway kinase cascade, at least in part via phosphorylation of Ser 127, which results in YAP 14-3-3 binding and cytoplasmic retention. Here we report that YAP is phosphorylated by Lats on all of the five consensus HXRXXS motifs. Phosphorylation of Ser 381 in one of them primes YAP for subsequent phosphorylation by CK1delta/epsilon in a phosphodegron. The phosphorylated phosphodegron then recruits the SCF(beta-TRCP) E3 ubiquitin ligase, which catalyzes YAP ubiquitination, ultimately leading to YAP degradation. The phosphodegron-mediated degradation and the Ser 127 phosphorylation-dependent translocation coordinately suppress YAP oncogenic activity. Our study identified CK1delta/epsilon as new regulators of YAP and uncovered an intricate mechanism of YAP regulation by the Hippo pathway via both S127 phosphorylation-mediated spatial regulation (nuclear-cytoplasmic shuttling) and the phosphodegron-mediated temporal regulation (degradation).

High concentrations of ozone in urban and industrial regions worldwide have long been a major air quality issue. With the rapid increase in fossil fuel consumption in China over the past three decades, the emission of chemical precursors to ozone—nitrogen oxides and volatile organic compounds—has increased sharply, surpassing that of North America and Europe and raising concerns about worsening ozone pollution in China. Historically, research and control have prioritized acid rain, particulate matter, and more recently fine particulate matter (PM2.5). In contrast, less is known about ozone pollution, partly due to a lack of monitoring of atmospheric ozone and its precursors until recently. This review summarizes the main findings from published papers on the characteristics and sources and processes of ozone and ozone precursors in the boundary layer of urban and rural areas of China, including concentration levels, seasonal variation, meteorology conducive to photochemistry and pollution transport, key production and loss processes, ozone dependence on nitrogen oxides and volatile organic compounds, and the effects of ozone on crops and human health. Ozone concentrations exceeding the ambient air quality standard by 100–200% have been observed in China's major urban centers such as Jing-Jin-Ji, the Yangtze River delta, and the Pearl River delta, and limited studies suggest harmful effect of ozone on human health and agricultural corps; key chemical precursors and meteorological conditions conductive to ozone pollution have been investigated, and inter-city/region transport of ozone is significant. Several recommendations are given for future research and policy development on ground-level ozone.

Unequivocal identification of the full composition of a gene is made difficult by the cryptic nature of regulatory elements. Regulatory elements are notoriously difficult to locate and may reside at considerable distances from the transcription units on which they operate and, moreover, may be incorporated into the structure of neighbouring genes. The importance of regulatory mutations as the basis of human abnormalities remains obscure. Here, we show that the chromosome 7q36 associated preaxial polydactyly, a frequently observed congenital limb malformation, results from point mutations in a Shh regulatory element. Shh, normally expressed in the ZPA posteriorly in the limb bud, is expressed in an additional ectopic site at the anterior margin in mouse models of PPD. Our investigations into the basis of the ectopic Shh expression identified the enhancer element that drives normal Shh expression in the ZPA. The regulator, designated ZRS, lies within intron 5 of the Lmbr1 gene 1 Mb from the target gene Shh. The ZRS drives the early spatio-temporal expression pattern in the limb of tetrapods. Despite the morphological differences between limbs and fins, an equivalent regulatory element is found in fish. The ZRS contains point mutations that segregate with polydactyly in four unrelated families with PPD and in the Hx mouse mutant. Thus point mutations residing in long-range regulatory elements are capable of causing congenital abnormalities, and possess the capacity to modify gene activity such that a novel gamut of abnormalities is detected.

Alzheimer's disease (AD) exhibits extensive oxidative stress throughout the body, being detected peripherally as well as associated with the vulnerable regions of the brain affected in disease. Abundant evidence not only demonstrates the full spectrum of oxidative damage to neuronal macromolecules, but also reveals the occurrence of oxidative events early in the course of the disease and prior to the formation of the pathology, which support an important role of oxidative stress in AD. As a disease of abnormal aging, AD demonstrates oxidative damage at levels that significantly surpass that of elderly controls, which suggests the involvement of additional factor(s). Structurally and functionally damaged mitochondria, which are more proficient at producing reactive oxygen species but less so in ATP, are also an early and prominent feature of the disease. Since mitochondria are also vulnerable to oxidative stress, it is likely that a vicious downward spiral involving the interactions between mitochondrial dysfunction and oxidative stress contributes to the initiation and/or amplification of reactive oxygen species that is critical to the pathogenesis of AD. This article is part of a Special Issue entitled: Misfolded Proteins, Mitochondrial Dysfunction and Neurodegenerative Diseases.

The Hippo signaling pathway is gaining recognition as an important player in both organ size control and tumorigenesis, which are physiological and pathological processes that share common cellular signaling mechanisms. Upon activation by stimuli such as high cell density in cell culture, the Hippo pathway kinase cascade phosphorylates and inhibits the Yes-associated protein (YAP)/TAZ transcription coactivators representing the major signaling output of the pathway. Altered gene expression resulting from YAP/TAZ inhibition affects cell number by repressing cell proliferation and promoting apoptosis, thereby limiting organ size. Recent studies have provided new insights into the Hippo signaling pathway, elucidating novel phosphorylation-dependent and independent mechanisms of YAP/Yki inhibition by the Hippo pathway, new Hippo pathway components, novel YAP target transcription factors and target genes, and the three-dimensional structure of the YAP-TEAD complex, and providing further evidence for the involvement of YAP and the Hippo pathway in tumorigenesis.

Tremendous efforts are being made to develop electrode materials, electrolytes, and separators for energy storage devices to meet the needs of emerging technologies such as electric vehicles, decarbonized electricity, and electrochemical energy storage. However, the sustainability concerns of lithium-ion batteries (LIBs) and next-generation rechargeable batteries have received little attention. Recycling plays an important role in the overall sustainability of future batteries and is affected by battery attributes including environmental hazards and the value of their constituent resources. Therefore, recycling should be considered when developing battery systems. Herein, we provide a systematic overview of rechargeable battery sustainability. With a particular focus on electric vehicles, we analyze the market competitiveness of batteries in terms of economy, environment, and policy. Considering the large volumes of batteries soon to be retired, we comprehensively evaluate battery utilization and recycling from the perspectives of economic feasibility, environmental impact, technology, and safety. Battery sustainability is discussed with respect to life-cycle assessment and analyzed from the perspectives of strategic resources and economic demand. Finally, we propose a 4H strategy for battery recycling with the aims of high efficiency, high economic return, high environmental benefit, and high safety. New challenges and future prospects for battery sustainability are also highlighted.

Abstract Background Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. Methods We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. Results Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown β-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. Conclusion A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.

RNA modifications play critical roles in important biological processes. However, the functions of N6-methyladenosine (m6A) mRNA modification in cancer biology and cancer stem cells remain largely unknown. Here, we show that m6A mRNA modification is critical for glioblastoma stem cell (GSC) self-renewal and tumorigenesis. Knockdown of METTL3 or METTL14, key components of the RNA methyltransferase complex, dramatically promotes human GSC growth, self-renewal, and tumorigenesis. In contrast, overexpression of METTL3 or inhibition of the RNA demethylase FTO suppresses GSC growth and self-renewal. Moreover, inhibition of FTO suppresses tumor progression and prolongs lifespan of GSC-grafted mice substantially. m6A sequencing reveals that knockdown of METTL3 or METTL14 induced changes in mRNA m6A enrichment and altered mRNA expression of genes (e.g., ADAM19) with critical biological functions in GSCs. In summary, this study identifies the m6A mRNA methylation machinery as promising therapeutic targets for glioblastoma.

The pandemic of 2019 coronavirus disease (COVID-19) has burdened an unprecedented psychological stress on people around the world, especially the medical workforce. The study focuses on assess the psychological status of them. The authors conducted a single-center, cross-sectional survey via online questionnaires. Occurrence of fear, anxiety and depression were measured by the numeric rating scale (NRS) on fear, Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD), respectively. A total of 2299 eligible participants were enrolled from the authors’ institution, including 2042 medical staff and 257 administrative staff. The severity of fear, anxiety and depression were significantly different between two groups. Furthermore, as compared to the non-clinical staff, front line medical staff with close contact with infected patients, including working in the departments of respiratory, emergency, infectious disease, and ICU, showed higher scores on fear scale, HAMA and HAMD, and they were 1.4 times more likely to feel fear, twice more likely to suffer anxiety and depression. The medical staff especially working in above-mentioned departments made them more susceptible to psychological disorders. Effective strategies toward to improving the mental health should be provided to these individuals.

ADVERTISEMENT RETURN TO ISSUEReviewNEXTAprotic and Aqueous Li–O2 BatteriesJun Lu†, Li Li‡, Jin-Bum Park§, Yang-Kook Sun*§, Feng Wu*‡, and Khalil Amine*†∥View Author Information† Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States‡ Beijing Key Laboratory of Environmental Science and Engineering, School of Chemical Engineering and the Environment, Beijing Institute of Technology, Beijing 100081, China§ Department of Energy Engineering, Hanyang University, Seoul 133-791, South Korea∥ Chemistry Department, Faculty of Science, King Abdulaziz University, 80203 Jeddah, Saudi Arabia*E-mail: [email protected]*E-mail: [email protected]*E-mail: [email protected]Cite this: Chem. Rev. 2014, 114, 11, 5611–5640Publication Date (Web):April 11, 2014Publication History Received16 October 2013Published online11 April 2014Published inissue 11 June 2014https://doi.org/10.1021/cr400573bCopyright © 2014 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views17413Altmetric-Citations897LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (22 MB) Get e-AlertsSUBJECTS:Atmospheric chemistry,Batteries,Electrochemical cells,Electrodes,Electrolytes Get e-Alerts

Here we present the first diploid genome sequence of an Asian individual. The genome was sequenced to 36-fold average coverage using massively parallel sequencing technology. We aligned the short reads onto the NCBI human reference genome to 99.97% coverage, and guided by the reference genome, we used uniquely mapped reads to assemble a high-quality consensus sequence for 92% of the Asian individual's genome. We identified approximately 3 million single-nucleotide polymorphisms (SNPs) inside this region, of which 13.6% were not in the dbSNP database. Genotyping analysis showed that SNP identification had high accuracy and consistency, indicating the high sequence quality of this assembly. We also carried out heterozygote phasing and haplotype prediction against HapMap CHB and JPT haplotypes (Chinese and Japanese, respectively), sequence comparison with the two available individual genomes (J. D. Watson and J. C. Venter), and structural variation identification. These variations were considered for their potential biological impact. Our sequence data and analyses demonstrate the potential usefulness of next-generation sequencing technologies for personal genomics.

Three papers in this issue demonstrate the production of functional induced neuronal (iN) cells from human fibroblasts, a procedure that holds great promise for regenerative medicine. Pang et al. show that a combination of the three transcription factors Ascl1 (also known as Mash1), Brn2 (or Pou3f2) and Myt1l greatly enhances the neuronal differentiation of human embryonic stem cells. When combined with the basic helix–loop–helix transcription factor NeuroD1, these factors can also convert fetal and postnatal human fibroblasts into iN cells. Caiazzo et al. use a cocktail of three transcription factors to convert prenatal and adult mouse and human fibroblasts into functional dopaminergic neurons. The three are Mash1, Nurr1 (or Nr4a2) and Lmx1a. Conversion is direct with no reversion to a progenitor cell stage, and it occurs in cells from Parkinson's disease patients as well as from healthy donors. Yoo et al. use an alternative approach. They show that microRNAs can have an instructive role in neural fate determination. Expression of miR-9/9* and miR-124 in human fibroblasts induces their conversion into functional neurons, and the process is facilitated by the addition of some neurogenic transcription factors. Neurogenic transcription factors and evolutionarily conserved signalling pathways have been found to be instrumental in the formation of neurons1,2. However, the instructive role of microRNAs (miRNAs) in neurogenesis remains unexplored. We recently discovered that miR-9* and miR-124 instruct compositional changes of SWI/SNF-like BAF chromatin-remodelling complexes, a process important for neuronal differentiation and function3,4,5,6. Nearing mitotic exit of neural progenitors, miR-9* and miR-124 repress the BAF53a subunit of the neural-progenitor (np)BAF chromatin-remodelling complex. After mitotic exit, BAF53a is replaced by BAF53b, and BAF45a by BAF45b and BAF45c, which are then incorporated into neuron-specific (n)BAF complexes essential for post-mitotic functions4. Because miR-9/9* and miR-124 also control multiple genes regulating neuronal differentiation and function5,7,8,9,10,11,12,13, we proposed that these miRNAs might contribute to neuronal fates. Here we show that expression of miR-9/9* and miR-124 (miR-9/9*-124) in human fibroblasts induces their conversion into neurons, a process facilitated by NEUROD2. Further addition of neurogenic transcription factors ASCL1 and MYT1L enhances the rate of conversion and the maturation of the converted neurons, whereas expression of these transcription factors alone without miR-9/9*-124 was ineffective. These studies indicate that the genetic circuitry involving miR-9/9*-124 can have an instructive role in neural fate determination.

We present primary results from the Sequencing Quality Control (SEQC) project, coordinated by the US Food and Drug Administration. Examining Illumina HiSeq, Life Technologies SOLiD and Roche 454 platforms at multiple laboratory sites using reference RNA samples with built-in controls, we assess RNA sequencing (RNA-seq) performance for junction discovery and differential expression profiling and compare it to microarray and quantitative PCR (qPCR) data using complementary metrics. At all sequencing depths, we discover unannotated exon-exon junctions, with >80% validated by qPCR. We find that measurements of relative expression are accurate and reproducible across sites and platforms if specific filters are used. In contrast, RNA-seq and microarrays do not provide accurate absolute measurements, and gene-specific biases are observed for all examined platforms, including qPCR. Measurement performance depends on the platform and data analysis pipeline, and variation is large for transcript-level profiling. The complete SEQC data sets, comprising >100 billion reads (10Tb), provide unique resources for evaluating RNA-seq analyses for clinical and regulatory settings.

Lung cancer is the second most common cancer and the leading cause of cancer death in the US. In 2020, an estimated 228 820 persons were diagnosed with lung cancer, and 135 720 persons died of the disease. The most important risk factor for lung cancer is smoking. Increasing age is also a risk factor for lung cancer. Lung cancer has a generally poor prognosis, with an overall 5-year survival rate of 20.5%. However, early-stage lung cancer has a better prognosis and is more amenable to treatment.To update its 2013 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review on the accuracy of screening for lung cancer with low-dose computed tomography (LDCT) and on the benefits and harms of screening for lung cancer and commissioned a collaborative modeling study to provide information about the optimum age at which to begin and end screening, the optimal screening interval, and the relative benefits and harms of different screening strategies compared with modified versions of multivariate risk prediction models.This recommendation statement applies to adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or have quit within the past 15 years.The USPSTF concludes with moderate certainty that annual screening for lung cancer with LDCT has a moderate net benefit in persons at high risk of lung cancer based on age, total cumulative exposure to tobacco smoke, and years since quitting smoking.The USPSTF recommends annual screening for lung cancer with LDCT in adults aged 50 to 80 years who have a 20 pack-year smoking history and currently smoke or have quit within the past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery. (B recommendation) This recommendation replaces the 2013 USPSTF statement that recommended annual screening for lung cancer with LDCT in adults aged 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years.

Abstract The pandemic of COVID-19 has posed an unprecedented threat to global public health. However, the interplay between the viral pathogen of COVID-19, SARS-CoV-2, and host innate immunity is poorly understood. Here we show that SARS-CoV-2 induces overt but delayed type-I interferon (IFN) responses. By screening 23 viral proteins, we find that SARS-CoV-2 NSP1, NSP3, NSP12, NSP13, NSP14, ORF3, ORF6 and M protein inhibit Sendai virus-induced IFN-β promoter activation, whereas NSP2 and S protein exert opposite effects. Further analyses suggest that ORF6 inhibits both type I IFN production and downstream signaling, and that the C-terminus region of ORF6 is critical for its antagonistic effect. Finally, we find that IFN-β treatment effectively blocks SARS-CoV-2 replication. In summary, our study shows that SARS-CoV-2 perturbs host innate immune response via both its structural and nonstructural proteins, and thus provides insights into the pathogenesis of SARS-CoV-2.

Colorectal cancer is the third leading cause of cancer death for both men and women, with an estimated 52 980 persons in the US projected to die of colorectal cancer in 2021. Colorectal cancer is most frequently diagnosed among persons aged 65 to 74 years. It is estimated that 10.5% of new colorectal cancer cases occur in persons younger than 50 years. Incidence of colorectal cancer (specifically adenocarcinoma) in adults aged 40 to 49 years has increased by almost 15% from 2000-2002 to 2014-2016. In 2016, 26% of eligible adults in the US had never been screened for colorectal cancer and in 2018, 31% were not up to date with screening.To update its 2016 recommendation, the US Preventive Services Task Force (USPSTF) commissioned a systematic review to evaluate the benefits and harms of screening for colorectal cancer in adults 40 years or older. The review also examined whether these findings varied by age, sex, or race/ethnicity. In addition, as in 2016, the USPSTF commissioned a report from the Cancer Intervention and Surveillance Modeling Network Colorectal Cancer Working Group to provide information from comparative modeling on how estimated life-years gained, colorectal cancer cases averted, and colorectal cancer deaths averted vary by different starting and stopping ages for various screening strategies.Asymptomatic adults 45 years or older at average risk of colorectal cancer (ie, no prior diagnosis of colorectal cancer, adenomatous polyps, or inflammatory bowel disease; no personal diagnosis or family history of known genetic disorders that predispose them to a high lifetime risk of colorectal cancer [such as Lynch syndrome or familial adenomatous polyposis]).The USPSTF concludes with high certainty that screening for colorectal cancer in adults aged 50 to 75 years has substantial net benefit. The USPSTF concludes with moderate certainty that screening for colorectal cancer in adults aged 45 to 49 years has moderate net benefit. The USPSTF concludes with moderate certainty that screening for colorectal cancer in adults aged 76 to 85 years who have been previously screened has small net benefit. Adults who have never been screened for colorectal cancer are more likely to benefit.The USPSTF recommends screening for colorectal cancer in all adults aged 50 to 75 years. (A recommendation) The USPSTF recommends screening for colorectal cancer in adults aged 45 to 49 years. (B recommendation) The USPSTF recommends that clinicians selectively offer screening for colorectal cancer in adults aged 76 to 85 years. Evidence indicates that the net benefit of screening all persons in this age group is small. In determining whether this service is appropriate in individual cases, patients and clinicians should consider the patient's overall health, prior screening history, and preferences. (C recommendation).

Accurate and real-time traffic flow prediction is important in Intelligent Transportation System (ITS), especially for traffic control. Existing models such as ARMA, ARIMA are mainly linear models and cannot describe the stochastic and nonlinear nature of traffic flow. In recent years, deep-learning-based methods have been applied as novel alternatives for traffic flow prediction. However, which kind of deep neural networks is the most appropriate model for traffic flow prediction remains unsolved. In this paper, we use Long Short Term Memory (LSTM) and Gated Recurrent Units (GRU) neural network (NN) methods to predict short-term traffic flow, and experiments demonstrate that Recurrent Neural Network (RNN) based deep learning methods such as LSTM and GRU perform better than auto regressive integrated moving average (ARIMA) model. To the best of our knowledge, this is the first time that GRU is applied to traffic flow prediction.

The activin receptor-like kinase 1 (ALK1) is a type I receptor for transforming growth factor-β (TGF-β) family proteins. Expression of ALK1 in blood vessels and mutations of the ALK1 gene in human type II hereditary hemorrhagic telangiectasia patients suggest that ALK1 may have an important role during vascular development. To define the function of ALK1 during development, we inactivated the ALK1 gene in mice by gene targeting. The ALK1 homozygous embryos die at midgestation, exhibiting severe vascular abnormalities characterized by excessive fusion of capillary plexes into cavernous vessels and hyperdilation of large vessels. These vascular defects are associated with enhanced expression of angiogenic factors and proteases and are characterized by deficient differentiation and recruitment of vascular smooth muscle cells. The blood vessel defects in ALK1-deficient mice are reminiscent of mice lacking TGF-β1, TGF-β type II receptor (TβR-II), or endoglin, suggesting that ALK1 may mediate TGF-β1 signal in endothelial cells. Consistent with this hypothesis, we demonstrate that ALK1 in endothelial cells binds to TGF-β1 and TβR-II. Furthermore, the ALK1 signaling pathway can inhibit TGF-β1-dependent transcriptional activation mediated by the known TGF-β1 type I receptor, ALK5. Taken together, our results suggest that the balance between the ALK1 and ALK5 signaling pathways in endothelial cells plays a crucial role in determining vascular endothelial properties during angiogenesis.

Gene expression data from microarrays are being applied to predict preclinical and clinical endpoints, but the reliability of these predictions has not been established. In the MAQC-II project, 36 independent teams analyzed six microarray data sets to generate predictive models for classifying a sample with respect to one of 13 endpoints indicative of lung or liver toxicity in rodents, or of breast cancer, multiple myeloma or neuroblastoma in humans. In total, >30,000 models were built using many combinations of analytical methods. The teams generated predictive models without knowing the biological meaning of some of the endpoints and, to mimic clinical reality, tested the models on data that had not been used for training. We found that model performance depended largely on the endpoint and team proficiency and that different approaches generated models of similar performance. The conclusions and recommendations from MAQC-II should be useful for regulatory agencies, study committees and independent investigators that evaluate methods for global gene expression analysis.

National Cancer Center (NCC) of China annually reports the nationwide statistics for cancer incidence and mortality using population-based cancer registry data from all available cancer registries in China. There were a total of 487 registries which reported high quality data of cancer incidence and mortality across China in 2016. The nationwide numbers of new cancer cases and deaths were estimated using the pooled cancer registry data, which were stratified by area (urban/rural), sex, age group (0, 1-4, 5-9, 10-14…85+) and cancer site for incidence and mortality, and then multiplied by corresponding national population. The world Segi's population was applied for the calculation of age-standardized rates. About 4,064,000 new cancer cases and 2,413,500 new cancer deaths occurred in China in 2016. Cancers of the lung, colon-rectum, stomach, liver and female breast were the top five common cancers, accounting for 57.4% of total cancer new cases. Cancers of the lung, liver, stomach, colon-rectum and esophagus were the five leading causes of cancer deaths, accounting for 69.3% of total cancer deaths. The crude and age-standardized incidence rates (ASIR) were 293.91 and 186.46 per 100,000 population, respectively. The crude mortality rate was 174.55/100,000 and the age-standardized mortality rate (ASMR) was 105.19/100,000. The ASIR was higher but the ASMR was lower in urban areas than that in rural areas. In past decades, the ASIR was relatively stable in males, but significantly increased by about 2.3% per year in females for overall cancers combined. In contrast, the ASMR significantly decreased by about 1.2% per year for both sexes during 2000-2016. Notably, the cancer-specific ASIR and ASMR of esophageal, stomach, and liver cancers decreased significantly, whereas both rates for cancers of the colon-rectum, prostate, female breast, cervix, and thyroid increased significantly. Cancer remains a major public health problem in China, which demands long-term collaborative efforts of a broad community. With the national guideline on cancer prevention and control, tailored cancer prevention and control programs are needed in different regions to help reduce the burden of these highly fatal diseases in China.

Wire-shaped micro-supercapacitor and micro-battery: Aligned multi-walled carbon nanotube fibers and composite fibers have been easily twisted to produce both wire-shaped supercapacitors and lithium ion batteries with high performances. The energy densities achieved 92.84 and 35.74 mWh/cm3 while the power densities could reach 3.87 and 2.43 W/cm3 during the charge and discharge process, respectively. The unique structure enables promising applications in various fields, e.g., these wires can be easily integrated into electronic textiles by a conventional weaving technique. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Multi-hop infrastructure wireless mesh networks offer increased reliability, coverage and reduced equipment costs over their single-hop counterpart, wireless LANs. Equipping wireless routers with multiple radios further improves the capacity by transmitting over multiple radios simultaneously using orthogonal channels. Efficient channel assignment and routing is essential for throughput optimization of mesh clients. Efficient channel assignment schemes can greatly relieve the interference effect of close-by transmissions; effective routing schemes can alleviate potential congestion on any gateways to the Internet, thereby improving per-client throughput. Unlike previous heuristic approaches, we mathematically formulate the joint channel assignment and routing problem, taking into account the interference constraints, the number of channels in the network and the number of radios available at each mesh router. We then use this formulation to develop a solution for our problem that optimizes the overall network throughput subject to fairness constraints on allocation of scarce wireless capacity among mobile clients. We show that the performance of our algorithms is within a constant factor of that of any optimal algorithm for the joint channel assignment and routing problem. Our evaluation demonstrates that our algorithm can effectively exploit the increased number of channels and radios, and it performs much better than the theoretical worst case bounds.

Ventricular arrhythmias and contractile dysfunction are the main causes of death in human heart failure (HF). In a rabbit HF model reproducing these same aspects of human HF, we demonstrate that a 2-fold functional upregulation of Na(+)-Ca(2+) exchange (NaCaX) unloads sarcoplasmic reticulum (SR) Ca(2+) stores, reducing Ca(2+) transients and contractile function. Whereas beta-adrenergic receptors (beta-ARs) are progressively downregulated in HF, residual beta-AR responsiveness at this critical HF stage allows SR Ca(2+) load to increase, causing spontaneous SR Ca(2+) release and transient inward current carried by NaCaX. A given Ca(2+) release produces greater arrhythmogenic inward current in HF (as a result of NaCaX upregulation), and approximately 50% less Ca(2+) release is required to trigger an action potential in HF. The inward rectifier potassium current (I(K1)) is reduced by 49% in HF, and this allows greater depolarization for a given NaCaX current. Partially blocking I(K1) in control cells with barium mimics the greater depolarization for a given current injection seen in HF. Thus, we present data to support a novel paradigm in which changes in NaCaX and I(K1), and residual beta-AR responsiveness, conspire to greatly increase the propensity for triggered arrhythmias in HF. In addition, NaCaX upregulation appears to be a critical link between contractile dysfunction and arrhythmogenesis.

Rare genetic variants contribute to complex disease risk; however, the abundance of rare variants in human populations remains unknown. We explored this spectrum of variation by sequencing 202 genes encoding drug targets in 14,002 individuals. We find rare variants are abundant (1 every 17 bases) and geographically localized, so that even with large sample sizes, rare variant catalogs will be largely incomplete. We used the observed patterns of variation to estimate population growth parameters, the proportion of variants in a given frequency class that are putatively deleterious, and mutation rates for each gene. We conclude that because of rapid population growth and weak purifying selection, human populations harbor an abundance of rare variants, many of which are deleterious and have relevance to understanding disease risk.

Cell attachment to the extracellular matrix (ECM) is crucial to cell physiology such as polarity, motility, and proliferation. In normal cells, loss of attachment to the ECM induces a specific type of apoptosis, termed anoikis. Resistance to anoikis in cancer cells promotes their survival in circulation and dispersion to distant anatomic sites, leading to tumor metastasis. The Yes-associated protein (YAP) transcription coactivator is a human oncogene and a key regulator of organ size. The Hippo tumor suppressor pathway phosphorylates and inhibits YAP. However, little is known about the signals that regulate the Hippo pathway. Here we report that through cytoskeleton reorganization, cell detachment activates the Hippo pathway kinases Lats1/2 and leads to YAP phosphorylation and inhibition. The detachment-induced YAP inactivation is required for anoikis in nontransformed cells, whereas in cancer cells with deregulation of the Hippo pathway, knockdown of YAP and TAZ restores anoikis. Furthermore, we provided evidence that Lats1/2 expression level is indeed significantly down-regulated in metastatic prostate cancer. Our findings provide a novel connection between cell attachment and anoikis through the Hippo pathway and have important implications in cancer therapeutics.

In this paper, we are presenting an alternative approach to the investigation of lower extremity coupling referred to as a dynamical systems approach. In this approach, we calculate the phase angle of each segment and joint angle. Pairing the key segment/joint motions, we use phase angles to determine the continuous relative phase and the variability of the continuous relative phase. Data from two studies illustrate the efficacy of the dynamical systems approach. Individuals who were asymptomatic, even though they may have anatomical aberrant structural problems (i.e. high Q-angle vs low Q-angle) showed no differences in the pattern of the continuous relative phase or in the variability of the continuous phase. However, differences in the variability of the continuous relative phase were apparent in comparing individuals who were symptomatic with patellofemoral pain with non-injured individuals. Patellofemoral pain individuals showed less variability in the continuous relative phase of the lower extremity couplings than did the healthy subjects. We hypothesize that the lower variability of the couplings in the symptomatic individuals indicates repeatable joint actions within a very narrow range. Relevance We claim that the traditional view of the variability of disordered movement is not tenable and suggest that there is a functional role for variability in lower extremity segment coupling during locomotion. While the methods described in this paper cannot determine a cause of the injury, they may be useful in the detection and treatment of running injuries.

Melanomas harbor aberrations in the c-Kit gene. We tested the efficiency of the tyrosine kinase inhibitor imatinib in selected patients with metastatic melanoma harboring c-Kit mutations or amplifications.Forty-three patients with metastatic melanoma harboring c-Kit aberrations were enrolled on this phase II trial. Each patient received a continuous dose of imatinib 400 mg/d unless intolerable toxicities or disease progression occurred. Fifteen patients who experienced progression of disease were allowed to escalate the dose to 800 mg/d.Forty-three patients were eligible for evaluation, and the median follow-up time was 12.0 months. The median progression-free survival (PFS) was 3.5 months, and the 6-month PFS rate was 36.6%. Rate of total disease control was 53.5%: 10 patients (23.3%; 95% CI, 10.2% to 36.4%) and 13 patients (30.2%; 95% CI, 16.0% to 44.4%) achieved partial response (PR) and stable disease (SD), respectively. Eighteen patients (41.9%) demonstrated regression of tumor mass. Notably, nine of the 10 PRs were observed in patients with mutations in exons 11 or 13. The 1-year overall survival (OS) rate was 51.0%. The median PFS and OS times for patients who had PR or SD versus disease progression were 9.0 months versus 1.5 months (P < .001) and 15.0 months versus 9.0 months (P = .036), respectively. Imatinib 400 mg/d was well tolerated, and only one of the 15 patients who received dose escalation to 800 mg/d achieved SD.Imatinib demonstrated significant activity in patients with metastatic melanoma harboring genetic c-Kit aberrations, with an overall response rate of 23.3%. Escalation to 800 mg/d could not restore disease control.

Forced obedience: Layer-structured montmorillonite (MMT) was used as a nanoreactor for the generation of planar pyridinic and pyrrolic N sites in nitrogen-doped graphene (NG; see picture). The selectivity for the formation of planar N sites was inversely proportional to the interspace width (δ) of the MMT and reached a maximum of 90.27 %. The NG catalyst exhibited low electrical resistance, high electrocatalytic activity, and good stability. The development of high-performance and low-cost catalytic materials for the oxygen reduction reaction (ORR) has been a major challenge for the large-scale application of fuel cells.1 Currently, platinum and platinum-based alloys are the most efficient ORR catalysts in fuel-cell cathodes;2 however, they cannot meet the demand for the widespread commercialization of fuel cells because of the scarcity of platinum. Thus, the ongoing search for platinum-free catalysts for the ORR has attracted much attention. Graphene, single-layer sheets of sp2-hybridized carbon atoms, has attracted tremendous attention and research interest.3 The abundance of free-flowing π electrons in carbon materials composed of sp2-hybridized carbon atoms makes these materials potential catalysts for reactions that require electrons, such as the ORR. However, these π electrons are too inert to be used directly in the ORR. In N-doped electron-rich carbon nanostructures, carbon π electrons have been shown to be activated through conjugation with lone-pair electrons from N dopants; thus, O2 molecules are reduced on the positively charged C atoms that neighbor N atoms.1a, 4 Recently, Hu and co-workers found that as long as the electroneutrality of the sp2-hybridized carbon atoms is broken and charged sites that favor O2 adsorption are created, these materials will be transformed into active metal-free ORR electrocatalysts regardless of whether the dopants are electron-rich (e.g., N) or electron-deficient (e.g., B).5 Nitrogen-doped carbon (NC) materials are considered to be promising catalysts because of their acceptable ORR activity, low cost, good durability, and environmental friendliness.1a, 4a, 6 However, their ORR activity is less competitive, especially in acidic media. Relative to commercial Pt/C, the difference in the half-wave potential for ORR is within 25 mV in alkaline electrolytes but is greater than 200 mV in acidic electrolytes.4a, 6 The activity of NC materials can be enhanced through efficient N doping with sufficient active species that favor ORR and through an increase in electrical conductivity.1a, 7 The annealing of graphitized carbon materials, such as carbon nanotubes8a,8b and microporous carbon black,4b, 8c in NH3 leads to insufficient substitution of nitrogen because of the well-ordered structure of the host materials.1b Alternatively, the direct pyrolysis of nitrogen-containing hydrocarbons or polymers produces NC materials with good incorporation of nitrogen.4a, 9 However, suitable pyrolysis temperatures are difficult to pinpoint; without optimization, temperatures that are excessively low or excessively high lead to low electronic conductivity or a remarkable loss of active N species, respectively.10 Recently, mesoporous-alumina-assisted and silica-template-assisted nitrogen incorporation, which can preserve a high content of N in synthesized NC materials, have been reported.11 However the activities of the resulting NC materials in the ORR were still significantly lower than that of Pt/C, even when the N content was as high as 10.7 atm %.12a Among three types of N atoms, that is, pyridinic, pyrrolic, and quaternary N, only the pyridinic and pyrrolic forms, which have planar structures, have been proven to be active in the ORR.4a, 7, 11 In contrast, quaternary N atoms, which possess a 3D structure, are not active in the ORR. The low electrical conductivity of NC materials with quaternary N atoms results from the interruption of their π–π conjugation by the 3D structure and is thought to be predominantly responsible for the poor catalysis.12 Therefore, the synthesis of NC materials with more planar pyridinic and pyrrolic N atoms and fewer quaternary N atoms is important for the preparation of ORR-active catalysts. Herein, we present a novel strategy for the selective synthesis of pyridinic- and pyrrolic-nitrogen-doped graphene (NG) by the use of layered montmorillonite (MMT) as a quasi-closed flat nanoreactor, which is open only along the perimeter to enable the entrance of aniline (AN) monomer molecules. The flat MMT nanoreactor, which is less than 1 nm thick, extensively constrains the formation of quaternary N because of its 3D structure but facilitates the formation of pyridinic and pyrrolic N. Nitrogen is well-known to be incorporated into quaternary N in tetrahedral sp3 hybridization but incorporated into pyridinic and pyrrolic N in planar sp2 hybridization.13 The confinement effect of MMT ensures that N is incorporated into the structure and that the graphitization is successful without significant loss of N species. Furthermore, planar pyridinic and pyrrolic N can be expected to be dominantly synthesized inside MMT because of the spatial confinement. Our results even indicate that the content of the planar pyridinic and pyrrolic N is inversely proportional to the interspace width (δ) of MMT. Electrochemical evaluations showed that the NG synthesized in MMT exhibited excellent electronic conductivity, high ORR activity, and good stability in acidic electrolytes. MMT was previously used to prepare two-dimensional graphite.14 However, it has thus far not been recognized that MMT can be used to exclude quaternary N during the synthesis of NG and can therefore enable the synthesis of NG with more planar pyridinic and pyrrolic N to catalyze the ORR. The procedure for the synthesis of NG inside MMT is illustrated in Figure 1. AN monomers were first intercalated into the layers of MMT, and then in situ oxidation polymerization was performed. An excess of MMT over AN was used to ensure that most of the AN monomers were intercalated into the layers of MMT and did not remain outside the MMT. The composite was dehydrated at 120 °C and then pyrolyzed at 900 °C under flowing N2 for 3 h. Two types of MMT with different interspacial widths, that is, Na-MMT (0.53 nm) and H-MMT (0.46 nm), were used to synthesize NG. The resultant NG samples are accordingly denoted as NG@MMT and NG@H-MMT, respectively. Unless otherwise stated, MMT refers to Na-MMT. For comparison, NC obtained by AN polymerization and pyrolysis without MMT and that obtained from a simple mixture of MMT were termed NC○MMT and NC⊙MMT, respectively. In the case of NC⊙MMT, AN monomers were not intercalated into the layers of MMT as they were in the case of NG@MMT; rather, they were simply directly mixed with MMT and then polymerized and pyrolyzed to simulate the case of NC formed between MMT particles. The crevice between MMT particles was estimated to be approximately 1 μm. The MMT in all samples was finally etched off in a 40 % HF solution. Schematic representation of the synthesis of NG@MMT. The procedure for the synthesis of NG@MMT was monitored by X-ray diffraction (XRD). The MMT maintained a well-defined layered structure with a layer distance (d001) of 1.46 nm after polyaniline (PANI) intercalation (see Figure S1 a in the Supporting Information). After the pyrolysis step at 900 °C, the layer distance of MMT decreased to 1.24 nm, and a graphite peak emerged in the XRD pattern at 27.5° with a d spacing of 0.323 nm (see Figure S1 b); this peak was assigned to superposition of the graphene layers. The graphite peak disappeared when MMT was removed because, in this case, no means of restricting the graphene-layer superposition, which resulted in the formation of graphite, was present. Meanwhile, a broad peak appeared at approximately 23.5° in the pattern of the final NG@MMT; this peak is the graphene (002) diffraction peak (see Figure S1 c). The broadness of the peak implies that the NG@MMT is randomly piled in a corrugated structure. The prepared NG@MMT is composed of ultrathin corrugated nanosheets (Figure 2; see also Figure S2). Notably, numerous edge planes appear on the surface of the NG@MMT nanosheets (Figure 2 C; see also Figure S2 c–e). Previous studies revealed that nitrogen-containing carbon structures with more exposed edge planes contain more ORR-active nitrogen groups on their surface.9b In contrast, the TEM image of NC○MMT reveals a large-scale spherical morphology (see Figure S3). From the Raman spectra (see Figure S4), the calculated IG/I2D ratio for the NG@MMT is 1.3, which indicates that the NG@MMT consists of 2–4 layers of graphene (approximately 1.5 nm thick).15a This result is identical to those of the AFM (see Figure S2 f), which show that the height of an NG@MMT flake is about 1.5–2.5 nm. Notably, the interspace of the MMT (0.53 nm, see Figure S5) only allows the presence of a single layer of graphene; therefore, 2–4 layers of graphene overlap after the MMT has been removed. The weak 2D peak for NC○MMT implies that NC○MMT is disordered and different from graphite.15b a,b) SEM (a) and TEM images (b) of NG@MMT. c) High-resolution TEM image of the edge of a NG@MMT nanosheet. The XPS spectra of the prepared samples clearly indicate the presence of carbon and nitrogen (see Figure S7). The existence of CN and CC (graphite-type) bonds in the matrix further confirms the N-doped graphite structure of the prepared samples (see Figure S7 b). The relative N/C ratio was only 3.85 % in NC○MMT but was 6.85, 4.22, 4.70, and 4.80 % in PANI (before pyrolysis), NG@MMT, NG@H-MMT, and NC⊙MMT, respectively; these ratios indicate that nitrogen loss during pyrolysis at high temperatures was alleviated by the introduction of MMT. As previously mentioned, pyridinic and pyrrolic N (planar N) are ORR-active catalysts but are unstable at high temperatures, at which quaternary and oxidized N sites would be dominant.4a, 11 More than 70 % of the N species in NC○MMT are oxidized (21.07 %) and quaternary (49.15 %) N, whereas planar N species only account for 23.67 % of the N species (Figure 3). These values are consistent with those previously reported for NC obtained from direct pyrolysis.4a, 6 In contrast, the planar-N content in NG@MMT and NG@H-MMT is as high as 80.32 and 90.27 %, respectively, after pyrolysis at 900 °C. These data suggest that the active N species, that is, pyridinic N and pyrrolic N species, were produced selectively and were well-preserved inside the interspace of the MMT flat nanoreactor at high temperatures. The planar-N content is strongly related to the interspace width of the MMT (Table 1). The yield of planar N species was highest when H-MMT with the smallest interspace width of 0.46 nm was used as a nanoreactor (90.27 %) and decreased to 80.32 % when MMT with δ=0.53 nm was used, further to 25.87 % when the synthesis was carried out between MMT particles (δ≈1 μm), and finally to 23.67 % when no MMT was used. The order of the amount of quaternary and oxidized N species produced was reversed. This phenomenon is attributed to the space confinement of the MMT quasi-closed flat nanoreactor. In the case of pyrolysis in MMT with a large δ value, there is no space confinement for NC formation (Figure 4). The incorporation of N occurs randomly at high temperatures, whereby the N atoms preferentially occupy the positions as quaternary N or oxidized N for stability. Thus, NG with quaternary N is primarily produced in cases in which no MMT is used or in cases in which NG is formed outside the layers of MMT or inside the layers of MMT with a large interspace. Inside the layers of MMT, NG with planar pyridinic and pyrrolic N sites is produced to a very large extent. Because of the torsion angle of the CN bond, that is, 0° for planar sp2-hybridized N and 60° for tetrahedral sp3-hybridized N,13 graphene with quaternary N forms an uneven structure, whereas graphene with pyridinic and pyrrolic N forms flat platelets. Therefore, the production of graphene with pyridinic N and pyrrolic N is more favorable in a flat nanoreactor than the production of graphene with quaternary N for steric reasons. When the layer distance is decreased further, as in H-MMT, the steric hindrance is further enhanced, and almost no space is left for uneven structure formation. Consequently, NG@H-MMT is doped with a high planar-nitrogen content of 90.27 %. N1s XPS spectra of PANI, NG@MMT, NG@H-MMT, NC⊙MMT, and NC○MMT. Schematic representation showing the selectivity inside and outside of MMT during NG synthesis. Sample Synthesis conditions δ [nm] Planar N [%] Quaternary and oxidized N [%] Nitrile N [%] Specific area [m2 g−1] jk at 0.7 V [mA cm−2] H2O2 yield [%][a] NC○MMT without MMT ∞ 23.67 70.22 6.11 171.5 0.1 30.03 NC⊙MMT between MMT particles ca. 103[b] 25.87 39.91 36.20 226.4 0.3 8.30 NG@MMT inside Na-MMT 0.56[c] 80.32 19.68 0 247.0 4.6 3.72 NG@H-MMT inside H-MMT 0.46[c] 90.27 9.73 0 290.3 9.2 2.18 Good electrical conductivity is a prime requirement for materials used in electrochemical applications.6a, 7a Electrochemical impedance spectroscopy (EIS) performed at high frequency (see the Supporting Information for details) revealed that the electrical resistance of the NG samples was significantly lower than that of the NC samples and similar to that of commercially available Vulcan XC-72R carbon (Figure 5 a). These results indicate that the electrical conductivity of the NG samples is as high as that of carbon. The highest electrical conductivity among the different N-doped materials was observed for NG@H-MMT and decreased in the order NG@MMT>NC○MMT>NC⊙MMT. Considered together with the N1s XPS data, the electrical conductivity of these N-doped materials is closely related to the quaternary- and oxidized-N content. The conductivity increases as the quaternary- and oxidized-N content decreases. NG@H-MMT, which had the lowest quaternary- and oxidized-N content, exhibited the highest electrical conductivity. NC⊙MMT is an exception; its low electrical conductivity is attributed to the large number of nitrile species (36.20 %). a) Bode spectra obtained through the application of a sine wave with an amplitude of 5.0 mV from 10 mHz to 10 kHz for different catalysts. b) Steady-state plots of ORR polarization (bottom), ring current (middle), and H2O2 yield (top) for different catalysts in O2-saturated 0.1 M HClO4. c) Polarization curves and corresponding power densities of membrane electrode assemblies fabricated with the NG@MMT cathode catalyst. The electrocatalytic activity of NG@MMT toward the ORR was first examined by linear sweep voltammetry (LSV) at a slow scanning rate of 2 mV s−1 (see Figure S8). The cathodic current with an onset potential of 0.895 V (versus the reversible hydrogen electrode, RHE) is well-defined in O2-saturated 0.5 M H2SO4; however, it is featureless in N2-saturated H2SO4. It was estimated from the Koutecky–Levich plot that the reaction electron number is 3.8 at 0.55 V versus RHE (see Figure S6b). We further evaluated the activity of the catalysts in rotating ring–disk electrode (RRDE) experiments. All of the RRDE experiments were performed in 0.1 M HClO4 to prevent Pt/C performance loss caused by bisulfate adsorption. The polarization curves for the catalysts are shown in Figure 5 b. The NG@H-MMT catalyst exhibited the highest activity. The signal of the half-wave potential on a NG@H-MMT catalyst electrode was only 60 mV less than that on a state-of-the-art carbon-supported platinum catalyst (Johnson Matthey, UK, 40 wt %, denoted as JM Pt/C) at a Pt loading of 25 μg Pt cm−2. The H2O2 yield was as low as 2.2 % at all potentials, whereas the maximum H2O2 yield on JM Pt/C was approximately 4.60 %, which is consistent with the value of 3–4 % reported previously.16 Given that the surface nitrogen group is closely related to the ORR activity of NC materials, a comprehensive comparison was made on the basis of high-resolution N1s XPS data combined with the results of the RRDE experiments. The results clearly indicate that the incorporation of planar nitrogen into materials plays an important role in the ORR process (Table 1). The kinetic current densities (jk) were maximized for NG@H-MMT and decreased in the order NG@MMT>NC⊙MMT>NC○MMT, with jk values of 9.2, 4.6, 0.3, and 0.1 mA cm−2, respectively, at 0.7 V. The same order of planar-N ratios was observed for these samples; that is, NG@H-MMT (90.27 %)>NG@MMT (80.32 %)>NC⊙MMT (25.87 %)> NC○MMT (23.67 %). The ORR activities of these N-doped materials increased as their planar-N content increased. The Brunauer–Emmet–Teller (BET) specific surface areas of NC○MMT, NC⊙MMT, NG@MMT, and NG@H-MMT are 171.55, 226.39, 247.01 and 290.27 m2 g−1, respectively (see Figure S9). The specific activities normalized with respect to the specific surface areas of the samples are 0.97, 2.21, 31.04 and 52.82 mA m−2, accordingly (see Figure S10). These results indicate that the specific activity strongly depends on the catalyst type rather than the BET specific surface area. The major reason for the activity enhancement is the density of surface active sites rather than the total surface area, although the importance of the specific surface area cannot be ruled out totally. Although the NG@MMT catalysts exhibited relatively high ORR activities, their stability is a prominent concern. We evaluated the stability of the NG@MMT catalysts by cycling the electrode not only in the potential range of 0.6–1.1 V in O2-saturated 0.1 M HClO4 but also in a larger potential range of 0–1.2 V in N2-saturated 0.5 M H2SO4 (see Figure S11). No noticeable change in the ORR catalytic activity was observed for the NG@MMT. In contrast, the ORR half-wave potential on the electrode prepared from JM Pt/C catalysts was negatively shifted by 22 mV after O2 cycling and negatively shifted by 73 mV after N2 cycling. Besides, the NG@MMT exhibited high selectivity toward the ORR with a remarkable tolerance for methanol (see in Figure S12). The performance of the single cell with the NG@MMT cathode catalyst and the state-of-the-art Pt/C cathode catalyst at a Pt loading of 0.1 mg cm−2 is shown in Figure 5 c. The maximum power output was 320 mW cm−2 for the NG@MMT and 451 mW cm−2 for Pt/C. Notably, no metal, let alone a precious metal, was present in the NG@MMT sample. We believe that the performance of these NG catalysts can be further improved by enhancing oxygen transport in the catalytic layer, as Dodelet and co-workers did. Dodelet and co-workers developed a catalyst based on Fe and a metal–organic framework with an impressive volumetric activity of 230 A cm−3 at 0.8 ViR-free.1d,1e Although some catalysts prepared with Fe and/or Co present showed similar or even better single-cell performance and ORR activity,1 no metal-free catalyst with such high activity in acidic environments has been reported previously. In summary, we have fabricated NG by a novel approach with the aid of MMT, which is an inexpensive flat nanoreactor for the fabrication of nanosheet materials. Planar N sites, which are catalytically active toward the ORR, were generated selectively with the flat nanoreactor. The selectivity for planar N strongly depends on the interspace width of the flat nanoreactor. The highest yield of planar N (90.3 %) was observed when H-MMT, with an interspace width of 0.46 nm, was used as a nanoreactor. The content of quaternary and oxidized N was restricted to less than 9.7 % because of steric hindrance. The prepared NG showed good N incorporation, excellent electronic conductivity, and good catalytic activity toward the ORR. This synthetic method avoids vacuum-based, elaborate procedures and thus provides a simple but efficient and versatile approach to the low-cost mass production of NG for industrial purposes that range from catalysis and sensors to supercapacitors and lithium-ion batteries. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Type 2 diabetes is an epidemic that is affecting an ever-increasing proportion of the US population. Although consumption of refined carbohydrates has increased and is thought to be related to the increased risk of type 2 diabetes, the ecologic effect of changes in the quality of carbohydrates in the food supply on the risk of type 2 diabetes remains to be quantified. The objective was to examine the correlation between consumption of refined carbohydrates and the prevalence of type 2 diabetes in the United States. In this ecologic correlation study, the per capita nutrient consumption in the United States between 1909 and 1997 obtained from the US Department of Agriculture was compared with the prevalence of type 2 diabetes obtained from the Centers for Disease Control and Prevention. In a univariate analysis, a significant correlation with diabetes prevalence was observed for dietary fat (r = 0.84, P < 0.001), carbohydrate (r = 0.55, P < 0.001), protein (r = 0.71, P < 0.001), fiber (r = 0.16, P = 0.03), corn syrup (r = 0.83, P < 0.001), and total energy (r = 0.75, P < 0.001) intakes. In a multivariate nutrient-density model, in which total energy intake was accounted for, corn syrup was positively associated with the prevalence of type 2 diabetes (β = 0.0132, P = 0.038). Fiber (β = −13.86, P < 0.01) was negatively associated with the prevalence of type 2 diabetes. In contrast, protein (P = 0.084) and fat (P = 0.79) were not associated with the prevalence of type 2 diabetes when total energy was controlled for. Increasing intakes of refined carbohydrate (corn syrup) concomitant with decreasing intakes of fiber paralleled the upward trend in the prevalence of type 2 diabetes observed in the United States during the 20th century.

An arbitrary unknown quantum state cannot be measured precisely or replicated perfectly. However, quantum teleportation enables unknown quantum states to be transferred reliably from one object to another over long distances, without physical travelling of the object itself. Long-distance teleportation is a fundamental element of protocols such as large-scale quantum networks and distributed quantum computation. But the distances over which transmission was achieved in previous teleportation experiments, which used optical fibres and terrestrial free-space channels, were limited to about 100 kilometres, owing to the photon loss of these channels. To realize a global-scale 'quantum internet' the range of quantum teleportation needs to be greatly extended. A promising way of doing so involves using satellite platforms and space-based links, which can connect two remote points on Earth with greatly reduced channel loss because most of the propagation path of the photons is in empty space. Here we report quantum teleportation of independent single-photon qubits from a ground observatory to a low-Earth-orbit satellite, through an uplink channel, over distances of up to 1,400 kilometres. To optimize the efficiency of the link and to counter the atmospheric turbulence in the uplink, we use a compact ultra-bright source of entangled photons, a narrow beam divergence and high-bandwidth and high-accuracy acquiring, pointing and tracking. We demonstrate successful quantum teleportation of six input states in mutually unbiased bases with an average fidelity of 0.80 ± 0.01, well above the optimal state-estimation fidelity on a single copy of a qubit (the classical limit). Our demonstration of a ground-to-satellite uplink for reliable and ultra-long-distance quantum teleportation is an essential step towards a global-scale quantum internet.

Tissue maintenance and homeostasis can be achieved through the replacement of dying cells by differentiating precursors or self-renewal of terminally differentiated cells or relies heavily on cellular longevity in poorly regenerating tissues. Regulatory T cells (T(reg) cells) represent an actively dividing cell population with critical function in suppression of lethal immune-mediated inflammation. The plasticity of T(reg) cells has been actively debated because it could factor importantly in protective immunity or autoimmunity. By using inducible labeling and tracking of T(reg) cell fate in vivo, or transfers of highly purified T(reg) cells, we have demonstrated notable stability of this cell population under physiologic and inflammatory conditions. Our results suggest that self-renewal of mature T(reg) cells serves as a major mechanism of maintenance of the T(reg) cell lineage in adult mice.

Single-atom metal–nitrogen–carbon (M–N–C) catalysts have sparked intense interests, but the catalytic contribution of N-bonding environment neighboring M–N4 sites lacks attention. Herein, a series of Fe–N–C nanoarchitectures have been prepared, which confer adjustable numbers of atomically dispersed Fe–N4 sites, tunable hierarchical micro-mesoporous structures and intensified exposure of interior active sites. The optimization between Fe–N4 single sites and carbon matrix delivers superior oxygen reduction reaction activity (half-wave potential of 0.915 V vs RHE in alkaline medium) with remarkable stability and high atom-utilization efficiency (almost 10-fold enhancement). Both experiments and theoretical calculations verified the selective C–N bond cleavage adjacent to Fe center induced by porosity engineering could form edge-hosted Fe–N4 moieties, and therefore lower the overall oxygen reduction reaction barriers comparing to intact atomic configuration. These findings provide a new pathway for the integrated engineering of geometric and electronic structures of single-atom materials to improve their catalytic performance.

Ongoing research to develop digestion-resistant starch for human health promotion integrates the disciplines of starch chemistry, agronomy, analytical chemistry, food science, nutrition, pathology, and microbiology. The objectives of this research include identifying components of starch structure that confer digestion resistance, developing novel plants and starches, and modifying foods to incorporate these starches. Furthermore, recent and ongoing studies address the impact of digestion-resistant starches on the prevention and control of chronic human diseases, including diabetes, colon cancer, and obesity. This review provides a transdisciplinary overview of this field, including a description of types of resistant starches; factors in plants that affect digestion resistance; methods for starch analysis; challenges in developing food products with resistant starches; mammalian intestinal and gut bacterial metabolism; potential effects on gut microbiota; and impacts and mechanisms for the prevention and control of colon cancer, diabetes, and obesity. Although this has been an active area of research and considerable progress has been made, many questions regarding how to best use digestion-resistant starches in human diets for disease prevention must be answered before the full potential of resistant starches can be realized.

This review systematically summarizes the limitations of solid electrolytes including inorganic solid electrolytes, solid polymer electrolytes, and composite solid electrolytes.

We report 2-year results from CheckMate 141 to establish the long-term efficacy and safety profile of nivolumab and outcomes by tumor PD-L1 expression in patients with recurrent or metastatic (R/M),platinum-refractory squamous cell carcinoma of the head and neck (SCCHN). Patients with R/M SCCHN with tumor progression/recurrence within 6 months of platinum therapy were randomized 2:1 to nivolumab 3 mg/kg every 2 weeks or investigator’s choice (IC). Primary endpoint: overall survival (OS). Data cutoff: September 2017. With 24.2 months’ minimum follow-up, nivolumab (n = 240) continued to improve OS vs IC (n = 121), hazard ratio (HR) = 0.68 (95% CI 0.54–0.86). Nivolumab nearly tripled the estimated 24-month OS rate (16.9%) vs IC (6.0%), and demonstrated OS benefit across patients with tumor PD-L1 expression ≥1% (HR [95% CI] = 0.55 [0.39–0.78]) and < 1% (HR [95% CI] = 0.73 [0.49–1.09]), and regardless of tumor HPV status. Estimated OS rates at 18, 24, and 30 months with nivolumab were consistent irrespective of PD-L1 expression (<1%/≥1%). In the nivolumab arm, there were no observed differences in baseline characteristics or safety profile between long-term survivors and the overall population. Grade 3–4 treatment-related adverse event rates were 15.3% and 36.9% for nivolumab and IC, respectively. Nivolumab significantly improved OS at the primary analysis and demonstrated prolonged OS benefit vs IC and maintenance of a manageable and consistent safety profile with 2-year follow-up. OS benefit was observed with nivolumab irrespective of PD-L1 expression and HPV status. (Clinicaltrials.gov: NCT02105636)

Many ad hoc routing protocols are based on some variant of flooding. Despite various optimizations, many routing messages are propagated unnecessarily. We propose a gossiping-based approach, where each node forwards a message with some probability, to reduce the overhead of the routing protocols. Gossiping exhibits bimodal behavior in sufficiently large networks: in some executions, the gossip dies out quickly and hardly any node gets the message; in the remaining executions, a substantial fraction of the nodes gets the message. The fraction of executions in which most nodes get the message depends on the gossiping probability and the topology of the network. In the networks we have considered, using gossiping probability between 0.6 and 0.8 suffices to ensure that almost every node gets the message in almost every execution. For large networks, this simple gossiping protocol uses up to 35% fewer messages than flooding, with improved performance. Gossiping can also be combined with various optimizations of flooding to yield further benefits. Simulations show that adding gossiping to AODV results in significant performance improvement, even in networks as small as 150 nodes. We expect that the improvement should be even more significant in larger networks.

Animals have evolved defense systems for surviving in a chemically diverse environment. Such systems should demonstrate plasticity, such as adaptive immunity, enabling a response to even unknown chemicals. The antioxidant transcription factor Nrf2 is activated in response to various electrophiles and induces cytoprotective enzymes that detoxify them. We report here the discovery of a multiple sensing mechanism for Nrf2 activation using zebrafish and 11 Nrf2-activating compounds. First, we showed that six of the compounds tested specifically target Cys-151 in Keap1, the ubiquitin ligase for Nrf2, while two compounds target Cys-273. Second, in addition to Nrf2 and Keap1, a third factor was deemed necessary for responding to three of the compounds. Finally, we isolated a zebrafish mutant defective in its response to seven compounds but not in response to the remaining four. These results led us to categorize Nrf2 activators into six classes and hypothesize that multiple sensing allows enhanced plasticity in the system.

The Yes-associated protein (YAP) is a transcription coactivator that plays a crucial role in organ size control by promoting cell proliferation and inhibiting apoptosis. The Hippo tumor suppressor pathway inhibits YAP through phosphorylation-induced cytoplasmic retention and degradation. Here we report a novel mechanism of YAP regulation by angiomotin (AMOT) family proteins via a direct interaction. Knockdown of AMOT family protein AMOTL2 in polarized Madin-Darby canine kidney (MDCK) cells leads to YAP activation, as indicated by decreased YAP tight junction localization, attenuated YAP phosphorylation, accumulation of nuclear YAP, and induction of YAP target gene expression. Transcriptional coactivator with PDZ-binding motif (TAZ), the YAP paralog, is also regulated by AMOT in a similar fashion. Furthermore, AMOTL2 knockdown results in loss of cell contact inhibition in a manner dependent on the functions of YAP and TAZ. Our results indicate a potential tumor-suppressing role of AMOT family proteins as components of the Hippo pathway, and demonstrate a novel mechanism of YAP and TAZ inhibition by AMOT-mediated tight junction localization. These observations provide a potential link between the Hippo pathway and cell contact inhibition.

Abstract Human embryonic stem cells (hESCs) randomly differentiate into multiple cell types during embryoid body (EB) development. To date, characterization of specific factors capable of influencing hematopoietic cell fate from hESCs remains elusive. Here, we report that the treatment of hESCs during EB development with a combination of cytokines and bone morphogenetic protein-4 (BMP-4), a ventral mesoderm inducer, strongly promotes hematopoietic differentiation. Hematopoietic progenitors of multiple lineages were generated from EBs and were found to be restricted to the population of progeny expressing cell surface CD45. Addition of BMP-4 had no statistically significant effect on hematopoietic differentiation but enabled significant enhancement in progenitor self-renewal, independent of cytokine treatment. Hematopoietic commitment was characterized as the temporal emergence of single CD45+ cells first detectable after day 10 of culture and was accompanied by expression of hematopoietic transcription factors. Despite the removal of cytokines at day 10, hematopoietic differentiation of hESCs continued, suggesting that cytokines act on hematopoietic precursors as opposed to differentiated hematopoietic cells. Our study establishes the first evidence for the role of cytokines and BMP-4 in promoting hematopoietic differentiation of hESC lines and provides an unprecedented system to study early developmental events that govern the initiation of hematopoiesis in the human.

Recent research progresses on high performance anode materials for high-energy sodium-ion batteries are comprehensively summarized.

We perform decoy-state quantum key distribution between a low-Earth-orbit satellite and multiple ground stations located in Xinglong, Nanshan, and Graz, which establish satellite-to-ground secure keys with ∼kHz rate per passage of the satellite Micius over a ground station. The satellite thus establishes a secure key between itself and, say, Xinglong, and another key between itself and, say, Graz. Then, upon request from the ground command, Micius acts as a trusted relay. It performs bitwise exclusive or operations between the two keys and relays the result to one of the ground stations. That way, a secret key is created between China and Europe at locations separated by 7600 km on Earth. These keys are then used for intercontinental quantum-secured communication. This was, on the one hand, the transmission of images in a one-time pad configuration from China to Austria as well as from Austria to China. Also, a video conference was performed between the Austrian Academy of Sciences and the Chinese Academy of Sciences, which also included a 280 km optical ground connection between Xinglong and Beijing. Our work clearly confirms the Micius satellite as a robust platform for quantum key distribution with different ground stations on Earth, and points towards an efficient solution for an ultralong-distance global quantum network.Received 6 December 2017DOI:https://doi.org/10.1103/PhysRevLett.120.030501© 2018 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasQuantum channelsQuantum communicationQuantum cryptographyQuantum networksQuantum opticsQuantum Information, Science & TechnologyAtomic, Molecular & Optical

Last year, at least 30,000 scientific papers used the Kohn-Sham scheme of density functional theory to solve electronic structure problems in a wide variety of scientific fields. Machine learning holds the promise of learning the energy functional via examples, bypassing the need to solve the Kohn-Sham equations. This should yield substantial savings in computer time, allowing larger systems and/or longer time-scales to be tackled, but attempts to machine-learn this functional have been limited by the need to find its derivative. The present work overcomes this difficulty by directly learning the density-potential and energy-density maps for test systems and various molecules. We perform the first molecular dynamics simulation with a machine-learned density functional on malonaldehyde and are able to capture the intramolecular proton transfer process. Learning density models now allows the construction of accurate density functionals for realistic molecular systems.Machine learning allows electronic structure calculations to access larger system sizes and, in dynamical simulations, longer time scales. Here, the authors perform such a simulation using a machine-learned density functional that avoids direct solution of the Kohn-Sham equations.

Enhancer-binding pluripotency regulators (Sox2 and Oct4) play a seminal role in embryonic stem (ES) cell-specific gene regulation. Here, we combine in vivo and in vitro single-molecule imaging, transcription factor (TF) mutagenesis, and ChIP-exo mapping to determine how TFs dynamically search for and assemble on their cognate DNA target sites. We find that enhanceosome assembly is hierarchically ordered with kinetically favored Sox2 engaging the target DNA first, followed by assisted binding of Oct4. Sox2/Oct4 follow a trial-and-error sampling mechanism involving 84-97 events of 3D diffusion (3.3-3.7 s) interspersed with brief nonspecific collisions (0.75-0.9 s) before acquiring and dwelling at specific target DNA (12.0-14.6 s). Sox2 employs a 3D diffusion-dominated search mode facilitated by 1D sliding along open DNA to efficiently locate targets. Our findings also reveal fundamental aspects of gene and developmental regulation by fine-tuning TF dynamics and influence of the epigenome on target search parameters.

Chimeric antigen receptors (CARs) have been used to redirect the specificity of autologous T cells against leukemia and lymphoma with promising clinical results. Extending this approach to allogeneic T cells is problematic as they carry a significant risk of graft-versus-host disease (GVHD). Natural killer (NK) cells are highly cytotoxic effectors, killing their targets in a non-antigen-specific manner without causing GVHD. Cord blood (CB) offers an attractive, allogeneic, off-the-self source of NK cells for immunotherapy. We transduced CB-derived NK cells with a retroviral vector incorporating the genes for CAR-CD19, IL-15 and inducible caspase-9-based suicide gene (iC9), and demonstrated efficient killing of CD19-expressing cell lines and primary leukemia cells in vitro, with marked prolongation of survival in a xenograft Raji lymphoma murine model. Interleukin-15 (IL-15) production by the transduced CB-NK cells critically improved their function. Moreover, iC9/CAR.19/IL-15 CB-NK cells were readily eliminated upon pharmacologic activation of the iC9 suicide gene. In conclusion, we have developed a novel approach to immunotherapy using engineered CB-derived NK cells, which are easy to produce, exhibit striking efficacy and incorporate safety measures to limit toxicity. This approach should greatly improve the logistics of delivering this therapy to large numbers of patients, a major limitation to current CAR-T-cell therapies.

Video indexing and retrieval have a wide spectrum of promising applications, motivating the interest of researchers worldwide. This paper offers a tutorial and an overview of the landscape of general strategies in visual content-based video indexing and retrieval, focusing on methods for video structure analysis, including shot boundary detection, key frame extraction and scene segmentation, extraction of features including static key frame features, object features and motion features, video data mining, video annotation, video retrieval including query interfaces, similarity measure and relevance feedback, and video browsing. Finally, we analyze future research directions.

Elucidation of the mutational landscape of human cancer has progressed rapidly and been accompanied by the development of therapeutics targeting mutant oncogenes. However, a comprehensive mapping of cancer dependencies has lagged behind and the discovery of therapeutic targets for counteracting tumor suppressor gene loss is needed. To identify vulnerabilities relevant to specific cancer subtypes, we conducted a large-scale RNAi screen in which viability effects of mRNA knockdown were assessed for 7,837 genes using an average of 20 shRNAs per gene in 398 cancer cell lines. We describe findings of this screen, outlining the classes of cancer dependency genes and their relationships to genetic, expression, and lineage features. In addition, we describe robust gene-interaction networks recapitulating both protein complexes and functional cooperation among complexes and pathways. This dataset along with a web portal is provided to the community to assist in the discovery and translation of new therapeutic approaches for cancer.

The microtubule-associated protein tau is a natively unfolded protein in solution, yet it is able to polymerize into the ordered paired helical filaments (PHF) of Alzheimer’s disease. In the splice isoforms lacking exon 10, this process is facilitated by the formation of β-structure around the hexapeptide motif PHF6 (306VQIVYK311) encoded by exon 11. We have investigated the structural requirements for PHF polymerization in the context of adult tau isoforms containing four repeats (including exon 10). In addition to the PHF6 motif there exists a related PHF6* motif (275VQIINK280) in the repeat encoded by the alternatively spliced exon 10. We show that this PHF6* motif also promotes aggregation by the formation of β-structure and that there is a cross-talk between the two hexapeptide motifs during PHF aggregation. We also show that two of the tau mutations found in hereditary frontotemporal dementias, ΔK280 and P301L, have a much stronger tendency for PHF aggregation which correlates with their high propensity for β-structure around the hexapeptide motifs. The microtubule-associated protein tau is a natively unfolded protein in solution, yet it is able to polymerize into the ordered paired helical filaments (PHF) of Alzheimer’s disease. In the splice isoforms lacking exon 10, this process is facilitated by the formation of β-structure around the hexapeptide motif PHF6 (306VQIVYK311) encoded by exon 11. We have investigated the structural requirements for PHF polymerization in the context of adult tau isoforms containing four repeats (including exon 10). In addition to the PHF6 motif there exists a related PHF6* motif (275VQIINK280) in the repeat encoded by the alternatively spliced exon 10. We show that this PHF6* motif also promotes aggregation by the formation of β-structure and that there is a cross-talk between the two hexapeptide motifs during PHF aggregation. We also show that two of the tau mutations found in hereditary frontotemporal dementias, ΔK280 and P301L, have a much stronger tendency for PHF aggregation which correlates with their high propensity for β-structure around the hexapeptide motifs. paired helical filament Fourier transform infrared spectroscopy frontotemporal dementia with parkinsonism linked to chromosome 17 trifluoroethanol thioflavine S Pathological protein aggregation is increasingly recognized as a common denominator underlying a variety of diseases, especially in diseases of the brain where the disposal of non-functional components and the regeneration of cells is slow or absent. This applies to inappropriately processed amyloid protein or hyperphosphorylated tau protein in Alzheimer’s disease, huntingtin with expanded polyglutamine tracts in Huntington’s disease, prion protein with altered conformations in Creutzfeld-Jacob’s disease, or accumulated α-synuclein in Parkinson’s disease, or mutated tau-protein in certain frontotemporal dementias, among others (1Lansbury Jr., P.T. Kosik K.S. Chem. Biol. 2000; 7: R9-R12Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar, 2Wanker E.E. Biol. Chem. 2000; 381: 937-942Crossref PubMed Scopus (128) Google Scholar, 3Prusiner S.B. Proc. Natl. Acad. Sci. U. S. A. 1998; 95: 13363-13383Crossref PubMed Scopus (5241) Google Scholar, 4Rochet J.C. Lansbury Jr., P.T. Curr. Opin. Struct. Biol. 2000; 10: 60-68Crossref PubMed Scopus (1002) Google Scholar, 5Goedert M. Prog. Brain Res. 1998; 117: 287-306Crossref PubMed Google Scholar). 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Certain buffers, certain domains of tau, and certain cofactors were necessary to make the aggregation process experimentally accessible. Thus, the repeat domain aggregates more readily than full-length tau (14Wille H. Drewes G. Biernat J. Mandelkow E.M. Mandelkow E. J. Cell Biol. 1992; 118: 573-584Crossref PubMed Scopus (436) Google Scholar); this domain also forms the core of Alzheimer PHFs1 (15Wischik C.M. Novak M. Thogersen H.C. Edwards P.C. Runswick M.J. Jakes R. Walker J.E. Milstein C. Roth M. Klug A. Proc. Natl. Acad. Sci. U. S. A. 1988; 85: 4506-4510Crossref PubMed Scopus (821) Google Scholar). Aggregation can be enhanced when tau is dimerized by oxidation (14Wille H. Drewes G. Biernat J. Mandelkow E.M. Mandelkow E. J. Cell Biol. 1992; 118: 573-584Crossref PubMed Scopus (436) Google Scholar, 16Schweers O. Mandelkow E.M. Biernat J. Mandelkow E. Proc. Natl. Acad. Sci. U. S. 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Abraham C. Selkoe D.J. Proc. Natl. Acad. Sci. U. S. A. 1986; 83: 503-507Crossref PubMed Scopus (495) Google Scholar), but this could have been caused by minor contributions from amyloid fibers, and later studies with Alzheimer fibers or recombinant aggregated tau did not reproduce the result (24Schweers O. Schonbrunn-Hanebeck E. Marx A. Mandelkow E. J. Biol. Chem. 1994; 269: 24290-24297Abstract Full Text PDF PubMed Google Scholar, 25Giannetti A.M. Lindwall G. Chau M.F. Radeke M.J. Feinstein S.C. Kohlstaedt L.A. Protein Sci. 2000; 9: 2427-2435Crossref PubMed Scopus (58) Google Scholar). It was therefore unclear whether the aggregation of tau was based on β-sheet formation or some other structural principle. The puzzle was partially answered recently when it was realized that a small fraction of tau, the hexapeptide motif PHF6 (306VQIVYK311), is capable of inducing tau aggregation via formation of a β-sheet interaction (26von Bergen M. Friedhoff P. Biernat J. Heberle J. Mandelkow E.M. Mandelkow E. Proc. Natl. Acad. Sci. U. S. A. 2000; 97: 5129-5134Crossref PubMed Scopus (800) Google Scholar). For intact tau, the increase in β-structure during aggregation is minor, which explains why the structures of PHFs made from whole tau are still dominated by the random coil conformation. However, the shift toward β-structure becomes visible with smaller constructs, such as the repeat domain or shorter peptides, because here the β-structure occupies a larger fraction of the protein. These results, however, left open the issue of the different tau isoforms. Alzheimer PHFs contain a mixture of all six isoforms of tau in the central nervous system (27Delacourte A. Defossez A. J. Neurol. Sci. 1986; 76: 173-186Abstract Full Text PDF PubMed Scopus (264) Google Scholar,28Jakes R. Novak M. Davison M. Wischik C.M. EMBO J. 1991; 10: 2725-2729Crossref PubMed Scopus (122) Google Scholar). The repeat domain is involved in binding to microtubules (together with the flanking domains, Fig. 1); the repeats also form the core of PHFs that may contain either all four repeats (R1, R2, R3, and R4; Fig.1) or only three (R1, R3, and R4 (29Lee G. Cowan N. Kirschner M. Science. 1988; 239: 285-288Crossref PubMed Scopus (572) Google Scholar, 30Goedert M. Spillantini M.G. Potier M.C. Ulrich J. Crowther R.A. EMBO J. 1989; 8: 393-399Crossref PubMed Scopus (884) Google Scholar)). The assembly-promoting hexapeptide motif PHF6 lies in repeat R3, and the earlier results had been obtained with tau domains and peptides lacking R2. The open question was, therefore, whether 4-repeat tau would obey similar principles of aggregation. In addition, because the extra repeat R2 can modify the rate of aggregation in different ways, depending on aggregation conditions (16Schweers O. Mandelkow E.M. Biernat J. Mandelkow E. Proc. Natl. Acad. Sci. U. S. A. 1995; 92: 8463-8467Crossref PubMed Scopus (353) Google Scholar, 21King M.E. Gamblin T.C. Kuret J. Binder L.I. J. Neurochem. 2000; 74: 1749-1757Crossref PubMed Scopus (156) Google Scholar), we asked how the two hexapeptide motifs would interact with each other. In the present study we show that 4-repeat tau isoforms contain another hexapeptide motif, similar to PHF6, which promotes β-structure formation and aggregation. A second open question was the role of tau mutations of frontotemporal dementias (FTDP-17). Most of the known mutations affect the C-terminal domain around the repeats, either because they change the splicing pattern (affecting the relative amount of 3-repeat versus 4-repeat tau) or because they introduce point mutations (for review see Ref. 31Hutton M. Ann. N. Y. Acad. Sci. 2000; 920: 63-73Crossref PubMed Scopus (83) Google Scholar). Because the repeat domain participates both in microtubule binding and in PHF aggregation, one can argue that the disease-causing effect of the mutations could be a change in either of these functions (for review see Ref. 32Goedert M. Spillantini M.G. Biochim. Biophys. Acta. 2000; 1502: 110-121Crossref PubMed Scopus (124) Google Scholar). Previous experiments had shown that point mutations tended to accelerate PHF aggregation in vitro, and two mutations had a particularly pronounced effect, P301L and ΔK280 (23Gamblin T.C. King M.E. Dawson H. Vitek M.P. Kuret J. Berry R.W. Binder L.I. Biochemistry. 2000; 39: 6136-6144Crossref PubMed Scopus (128) Google Scholar, 33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar, 34Nacharaju P. Lewis J. Easson C. Yen S. Hackett J. Hutton M. Yen S.H. FEBS Lett. 1999; 447: 195-199Crossref PubMed Scopus (238) Google Scholar, 35Goedert M. Jakes R. Crowther R.A. FEBS Lett. 1999; 450: 306-311Crossref PubMed Scopus (224) Google Scholar). Because these two mutations were near or in the assembly-promoting hexapeptide motifs, we suspected that the mutations could increase the propensity for β-sheet formation and aggregation. We show that this is indeed the case. In fact, the tendency of the ΔK280 for β-sheet formation is so strong that one can achieve aggregation of the repeat domain within minutes, and the mutant ΔK280 is able to polymerize even in the absence of the polyanionic cofactors commonly used to promote aggregation. These features might explain the toxic effect of these mutants in frontotemporal neurodegeneration. Heparin (averageM r of 3000) and thioflavine S were obtained from Sigma. Human tau isoforms and constructs (Fig. 1) were expressed inEscherichia coli as described (36Biernat J. Mandelkow E.M. Schroter C. Lichtenberg-Kraag B. Steiner B. Berling B. Meyer H. Mercken M. Vandermeeren A. Goedert M. Mandelkow E. EMBO J. 1992; 11: 1593-1597Crossref PubMed Scopus (439) Google Scholar). The numbering of the amino acids is that of the isoform htau40 containing 441 residues (37Goedert M. Spillantini M.G. Jakes R. Rutherford D. Crowther R.A. Neuron. 1989; 3: 519-526Abstract Full Text PDF PubMed Scopus (1958) Google Scholar). The protein was expressed and purified as described elsewhere making use of the heat stability and Mono S fast protein liquid chromatography (Amersham Biosciences) (38Gustke N. Trinczek B. Biernat J. Mandelkow E.M. Mandelkow E. Biochemistry. 1994; 33: 9511-9522Crossref PubMed Scopus (547) Google Scholar). The purity of the proteins was analyzed by SDS-PAGE. Protein concentrations were determined by the Bradford assay. Synthetic peptides were obtained from Eurogentec SA (Seraing, Belgium). The mutations of K18 (G272V, N279K, ΔK280, P301L, and V337M) were created by site-directed mutagenesis using the QuikChange kit (Stratagene) and the plasmid pNG2-K18 (33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar). Plasmids were sequenced on both strands. Aggregation was induced by incubating varying concentrations of tau isoforms or tau constructs and fragments (typically in the range of 1–100 μm) in volumes of 20–500 μl at 37 °C in 50 mm ammonium acetate, pH 7.0, or phosphate-buffered saline, pH 7.4, 1 mm dithiothreitol containing anionic cofactors (heparin) as described (22Friedhoff P. Schneider A. Mandelkow E.M. Mandelkow E. Biochemistry. 1998; 37: 10223-10230Crossref PubMed Scopus (365) Google Scholar, 33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar). Incubation times varied between minutes up to several days. The formation of aggregates was ascertained by thioflavine S fluorescence and electron microscopy as described (22Friedhoff P. Schneider A. Mandelkow E.M. Mandelkow E. Biochemistry. 1998; 37: 10223-10230Crossref PubMed Scopus (365) Google Scholar, 33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar). Soluble tau proteins were precipitated by acetone, and the pellets were washed with 90% ethanol in water and dried by vacuum, and the protein was dissolved in D2O (Sigma). Preformed filaments were centrifuged at 100,000 × g. The supernatant was discarded, and the pellet was resuspended in D2O and incubated for at least 2 h before measuring. FTIR experiments were performed on a Jasco FT-IR410 instrument (Jasco, Groß-Umstadt, Germany). Atmospheric water vapor was removed by flushing the spectrometer with nitrogen. Interferograms were recorded between 1700 and 1600 cm−1 at a spectral resolution of 1 cm−1, and 128 spectra were averaged. They were acquired in the transition mode using CaF2 cells, separated by spacers of different thicknesses (usually 25 μm). After recording a reference spectrum of the instrument and of the used D2O lot, the protein solutions were applied, and the absorbance spectrum of the sample was measured. The D2O spectra and sample spectra were first corrected for the water vapor background before subtracting the D2O spectra from the sample spectrum. To facilitate comparison the spectra were then normalized with respect to their maxima. Spectra were recorded repeatedly for every sample (up to 6 times); there was no significant difference between different preparations of a protein or different authors performing the experiments. K18/ΔK280 was allowed to polymerize into PHFs using concentrations of at least 500 μm in the absence of heparin, centrifuged at 100,000 × g. The pellets were placed into the wide end of a borosilicate capillary tube with a diameter of 0.5 mm and pushed down using a 2% agarose cushion. The samples were dried at room temperature. Diffraction patterns were recorded on a rotating anode x-ray generator (Rigaku U200) operated at 50 kV, 100 mA, λ = 1.5418 Å (CuKα), and equipped with an image plate detector (MarResearch, Hamburg, Germany). Tau in the human central nervous system occurs in six isoforms; the two inserts near the N terminus and the second of four imperfect repeats in the C-terminal half may be absent because of alternative splicing (Fig.1 A). The repeat domain, in combination with its proline-rich flanking domains, is important for microtubule binding (38Gustke N. Trinczek B. Biernat J. Mandelkow E.M. Mandelkow E. Biochemistry. 1994; 33: 9511-9522Crossref PubMed Scopus (547) Google Scholar, 39Goode B.L. Feinstein S.C. J. Cell Biol. 1994; 124: 769-782Crossref PubMed Scopus (346) Google Scholar); it forms the core of PHFs in Alzheimer’s disease (15Wischik C.M. Novak M. Thogersen H.C. Edwards P.C. Runswick M.J. Jakes R. Walker J.E. Milstein C. Roth M. Klug A. Proc. Natl. Acad. Sci. U. S. A. 1988; 85: 4506-4510Crossref PubMed Scopus (821) Google Scholar) and also assembles more readily than full-length tau intobona fide PHFs in vitro (14Wille H. Drewes G. Biernat J. Mandelkow E.M. Mandelkow E. J. Cell Biol. 1992; 118: 573-584Crossref PubMed Scopus (436) Google Scholar). For studying the principles of assembly, we therefore used recombinant full-length tau isoforms and tau constructs comprising either four repeats (K18, Fig.1 B) or three repeats (repeats 1, 3, and 4, construct K19, corresponding to fetal tau, Fig. 1 C). As shown previously, in 3R-tau the hexapeptide motif PHF6 (306VQIVYK311, Fig. 1, D and E) is crucial for PHF assembly by inducing local β-structure (26von Bergen M. Friedhoff P. Biernat J. Heberle J. Mandelkow E.M. Mandelkow E. Proc. Natl. Acad. Sci. U. S. A. 2000; 97: 5129-5134Crossref PubMed Scopus (800) Google Scholar). A comparison of the four repeats shows that a homologous motif is present in the second repeat (termed PHF6*,275VQIINK280, Fig. 1 E) but not in repeats 1 and 4. We noted that the hexapeptide motifs were close to point mutations in tau described for certain frontotemporal dementias such as G272V, N279K, ΔK280, P301L, or S305N (Fig. 1 B; for review see Refs. 31Hutton M. Ann. N. Y. Acad. Sci. 2000; 920: 63-73Crossref PubMed Scopus (83) Google Scholar and 32Goedert M. Spillantini M.G. Biochim. Biophys. Acta. 2000; 1502: 110-121Crossref PubMed Scopus (124) Google Scholar). Although some tau mutations in FTDP-17 exert their effect on the mRNA level by altering the splicing pattern, we expected that additional disease-causing changes might take place on the protein level. The two best known properties of tau protein are (i) the binding and stabilization of microtubules and (ii) the pathological aggregation to PHFs. Several groups have studied these issues (23Gamblin T.C. King M.E. Dawson H. Vitek M.P. Kuret J. Berry R.W. Binder L.I. Biochemistry. 2000; 39: 6136-6144Crossref PubMed Scopus (128) Google Scholar, 34Nacharaju P. Lewis J. Easson C. Yen S. Hackett J. Hutton M. Yen S.H. FEBS Lett. 1999; 447: 195-199Crossref PubMed Scopus (238) Google Scholar, 35Goedert M. Jakes R. Crowther R.A. FEBS Lett. 1999; 450: 306-311Crossref PubMed Scopus (224) Google Scholar, 40D'Souza I. Poorkaj P. Hong M. Nochlin D. Lee V.M. Bird T.D. Schellenberg G.D. Proc. Natl. Acad. Sci. U. S. A. 1999; 96: 5598-5603Crossref PubMed Scopus (430) Google Scholar, 41Hong M. Zhukareva V. Vogelsberg-Ragaglia V. Wszolek Z. Reed L. Miller B.I. Geschwind D.H. Bird T.D. McKeel D. Goate A. Morris J.C. Wilhelmsen K.C. Schellenberg G.D. Trojanowski J.Q. Lee V.M. Science. 1998; 282: 1914-1917Crossref PubMed Scopus (837) Google Scholar, 42DeTure M. Ko L.W. Yen S. Nacharaju P. Easson C. Lewis J. van Slegtenhorst M. Hutton M. Yen S.H. Brain Res. 2000; 853: 5-14Crossref PubMed Scopus (72) Google Scholar, 43Hasegawa M. Smith M.J. Goedert M. FEBS Lett. 1998; 437: 207-210Crossref PubMed Scopus (422) Google Scholar, 44Hasegawa M. Smith M.J. Iijima M. Tabira T. Goedert M. FEBS Lett. 1999; 443: 93-96Crossref PubMed Scopus (175) Google Scholar, 45Dayanandan R. Van Slegtenhorst M. Mack T.G. Ko L. Yen S.H. Leroy K. Brion J.P. Anderton B.H. Hutton M. Lovestone S. FEBS Lett. 1999; 446: 228-232Crossref PubMed Scopus (181) Google Scholar, 46Arrasate M. Perez M. Armas-Portela R. Avila J. FEBS Lett. 1999; 446: 199-202Crossref PubMed Scopus (105) Google Scholar) with some variation in the results. Our own studies of mutant tau proteins showed a modest but measurable decrease in microtubule stabilization. There was no systematic trend for PHF formation, but two mutations, ΔK280 and P301L, had a remarkable tendency to aggregate (33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar). This suggested that there might be an interplay between the β-inducing hexapeptide motifs and the mutations in tau. Conformational analysis of monomeric tau reveals a mostly random coil conformation by x-rays and CD (24Schweers O. Schonbrunn-Hanebeck E. Marx A. Mandelkow E. J. Biol. Chem. 1994; 269: 24290-24297Abstract Full Text PDF PubMed Google Scholar, 35Goedert M. Jakes R. Crowther R.A. FEBS Lett. 1999; 450: 306-311Crossref PubMed Scopus (224) Google Scholar, 47Jicha G.A. Rockwood J.M. Berenfeld B. Hutton M. Davies P. Neurosci. Lett. 1999; 260: 153-156Crossref PubMed Scopus (37) Google Scholar, 48Eidenmuller J. Fath T. Hellwig A. Reed J. Sontag E. Brandt R. Biochemistry. 2000; 39: 13166-13175Crossref PubMed Scopus (103) Google Scholar). By using FTIR as a sensitive method to detect β-structure, a similar dominance of random coil structure is observed for all tau constructs in solution which we have studied thus far (Fig. 2 and3). The random coil conformation of the soluble protein is in marked contrast to the regular appearance of the paired helical filaments found in Alzheimer’s disease and other tauopathies.Figure 3FTIR spectra of FTDP-17 mutations introduced into the 4-repeat construct K18. Note that in all cases there is a shift toward β-structure upon aggregation (dashed line), compared with the soluble protein (solid line). Polymerization was performed in the presence of heparin, except where noted (K18ΔK280-heparin). From top tobottom : K18wt (control), G272V, N279K, ΔK280 with heparin, ΔK280 without heparin, P301L, and V337M. wt, wild type.View Large Image Figure ViewerDownload Hi-res image Download (PPT) PHFs assembled from full-length tau show only a weak increase in β-structure (Fig. 2). However, this becomes more clearly detectable with tau constructs comprising roughly the repeat domain (which also forms the core of Alzheimer PHFs), in particular when using FTIR spectroscopy which is more sensitive for β-structure than CD. In the experiments described here the sensitivity was enhanced by first polymerizing the protein and then pelleting the aggregates and measuring the pellet and supernatant separately. Fig. 2 A shows the spectra of K19 in the soluble and in the polymerized state (solid and dashed lines). The monomeric protein exhibits a peak of absorbance in the amide I band around 1645 cm−1, indicating mostly random coil structure (49Byler D.M. Susi H. Biopolymers. 1986; 25: 469-487Crossref PubMed Scopus (2806) Google Scholar). The spectrum of the polymerized protein exhibits a maximum around 1630 cm−1 indicating an increased content of β-sheet. The same is true for the construct K18 containing four repeats (Fig.2 B); the maximum shifts from 1645 to 1625 cm−1upon polymerization. For comparison this procedure was also performed with the full-length tau isoforms htau23 and htau40 (Fig. 2,C and D); in these cases the polymerization induces only a shoulder at 1625 cm−1 or some broadening of the peak, consistent with the fact that only a small fraction of the full-length protein is involved in forming β-structure during aggregation. Next we wanted to determine whether mutated forms of tau occurring in frontotemporal dementias (FTDP-17) undergo similar structural transitions during PHF aggregation. Judging by their CD spectra, all full-length tau proteins containing one of the FTDP-17 mutations showed a structure similar to normal full-length tau in solution, dominated by the random coil conformation (33Barghorn S. Zheng-Fischhofer Q. Ackmann M. Biernat J. von Bergen M. Mandelkow E.M. Mandelkow E. Biochemistry. 2000; 39: 11714-11721Crossref PubMed Scopus (300) Google Scholar). To enhance the signal and the rate of aggregation, we cloned and expressed the mutants G272V, N279K, ΔK280, P301L, and V337M on the basis of the 4-repeat construct K18. Fig. 3 shows the FTIR traces obtained before and after assembly of the K18 mutants in the presence of heparin. In all cases, the spectra of the unpolymerized samples had a maximum around 1645 cm−1(typical of random coil), and assembly induced a shift of the maximum to 1620–1625 cm−1 (indicating more β-structure). A special case was the mutant K18/ΔK280 whose FTIR spectrum showed a distinct shoulder at 1625 cm−1 even without inducing aggregation with heparin (arrows in Fig. 3; see also assembly studies below). This can be explained by the high intrinsic tendency for aggregation which results in the spontaneous formation of oligomers, as confirmed by gel filtration (data not shown) and the higher initial ThS fluorescence level (Fig. 6 A). The most direct demonstration of β-structure within PHFs is x-ray fiber diffraction. Earlier experiments with PHFs isolated from Alzheimer brain tissue did not show evidence for β-structure (24Schweers O. Schonbrunn-Hanebeck E. Marx A. Mandelkow E. J. Biol. Chem. 1994; 269: 24290-24297Abstract Full Text PDF PubMed Google Scholar). However, because the overall β-content in PHFs aggregated from full-length tau is low, we used the construct K18 which has a higher fraction of β-structure, and we tried to align the PHFs in the sample by stretching and applying magnetic orientation that had been successful for orienting fibrous proteins, including fibers from β-amyloid (50Fraser P.E. McLachlan D.R. Surewicz W.K. Mizzen C.A. Snow A.D. Nguyen J.T. Kirschner D.A. J. Mol. Biol. 1994; 244: 64-73Crossref PubMed Scopus (153) Google Scholar). As shown in Fig.4, the degree of orientation remained low but was sufficient to detect the characteristic reflections from a cross-β-structure (meridional 0.47 and equatorial 1 nm reflections). This means that the building blocks responsible for PHF aggregation have their β-strands oriented mainly perpendicular to the PHF axis. This arrangement is reminiscent of other amyloid fibers (for review see Ref. 51Sunde M. Serpell L.C. Bartlam M. Fraser P.E. Pepys M.B. Blake C.C. J. Mol. Biol. 1997; 273: 729-739Crossref PubMed Scopus (1469) Google Scholar). To analyze the structural properties of t

Pseudomonas aeruginosa is a ubiquitous environmental bacterium and an important opportunistic human pathogen. Generally, the acquisition of genes in the form of pathogenicity islands distinguishes pathogenic isolates from nonpathogens. We therefore sequenced a highly virulent strain of P. aeruginosa, PA14, and compared it with a previously sequenced (and less pathogenic) strain, PAO1, to identify novel virulence genes. The PA14 and PAO1 genomes are remarkably similar, although PA14 has a slightly larger genome (6.5 megabses [Mb]) than does PAO1 (6.3 Mb). We identified 58 PA14 gene clusters that are absent in PAO1 to determine which of these genes, if any, contribute to its enhanced virulence in a Caenorhabditis elegans pathogenicity model. First, we tested 18 additional diverse strains in the C. elegans model and observed a wide range of pathogenic potential; however, genotyping these strains using a custom microarray showed that the presence of PA14 genes that are absent in PAO1 did not correlate with the virulence of these strains. Second, we utilized a full-genome nonredundant mutant library of PA14 to identify five genes (absent in PAO1) required for C. elegans killing. Surprisingly, although these five genes are present in many other P. aeruginosa strains, they do not correlate with virulence in C. elegans. Genes required for pathogenicity in one strain of P. aeruginosa are neither required for nor predictive of virulence in other strains. We therefore propose that virulence in this organism is both multifactorial and combinatorial, the result of a pool of pathogenicity-related genes that interact in various combinations in different genetic backgrounds.

Novel sulfur/polythiophene composites with core/shell structure composites were synthesized via an in situ chemical oxidative polymerization method with chloroform as a solvent, thiophene as a reagent, and iron chloride as an oxidant at 0 °C. Different ratios of the sulfur/polythiophene composites were characterized by elemental analysis, FTIR, XRD, SEM, TEM, and electrochemical methods. A suitable ratio for the composites was found to be 71.9% sulfur and 18.1% polythiophene as determined by CV and EIS results. Conductive polythiophene acts as a conducting additive and a porous adsorbing agent. It was uniformly coated onto the surface of the sulfur powder to form a core/shell structure, which effectively enhances the electrochemical performance and cycle life of the sulfur cells. The initial discharge capacity of the active material was 1119.3 mA h g−1, sulfur and the remaining capacity was 830.2 mA h g−1 sulfur after 80 cycles. After a rate test from 100 to 1600 mA g−1 sulfur, the cell remained at 811 mA h g−1 sulfur after 60 cycles when the current density returned to 100 mA g−1 sulfur. The sulfur utilization, the cycle life, and the rate performance of the S−PTh core/shell electrode in a lithium−sulfur battery improved significantly compared to that of the pure sulfur electrode. The pore and thickness of the shell affected the battery performance of the lithium ion diffusion channels.

A versatile and scalable mixed solvent strategy was developed to prepare monolayer C3N4 nanosheets with tunable concentration for the first time. This approach could also be used to prepare other 2D nanosheets from their layered materials (such as MoS2, BN, WS2 etc.). The structural features and intrinsic semiconductor properties of the as-prepared C3N4 nanosheets have been investigated in detailed. The photocatalytic activities were evaluated by photocatalytic oxidation of both benzyl alcohol and rhodamine B (RhB) under visible light irradiation. Results showed that the as-prepared monolayer C3N4 nanosheets with thickness of 0.4 nm still retained the structural features of g-C3N4 layer. The functionalities of C3N4 nanosheets well inherited from the layered parent counterpart. Furthermore, due to the exceptionally high 2D anisotropy, C3N4 nanosheets showed the distinctive physicochemical properties and unique electronic structures, such as high surface area, lower surface defects, stronger reduction ability of the photogenerated electrons, increased photoelectric response, and promoted the charge-carrier migration and separation. All of these favorable factors co-contributed to the greatly improved photocatalytic activities over C3N4 nanosheets compared with those of its bulk counterpart.

Abstract Despite recent progress in our understanding of carotenogenesis in plants, the mechanisms that govern overall carotenoid accumulation remain largely unknown. The Orange (Or) gene mutation in cauliflower (Brassica oleracea var botrytis) confers the accumulation of high levels of β-carotene in various tissues normally devoid of carotenoids. Using positional cloning, we isolated the gene representing Or and verified it by functional complementation in wild-type cauliflower. Or encodes a plastid-associated protein containing a DnaJ Cys-rich domain. The Or gene mutation is due to the insertion of a long terminal repeat retrotransposon in the Or allele. Or appears to be plant specific and is highly conserved among divergent plant species. Analyses of the gene, the gene product, and the cytological effects of the Or transgene suggest that the functional role of Or is associated with a cellular process that triggers the differentiation of proplastids or other noncolored plastids into chromoplasts for carotenoid accumulation. Moreover, we demonstrate that Or can be used as a novel genetic tool to induce carotenoid accumulation in a major staple food crop. We show here that controlling the formation of chromoplasts is an important mechanism by which carotenoid accumulation is regulated in plants.

In this work, a hydrometallurgical process based on leaching is applied to recover cobalt and lithium from spent lithium ion batteries (LIBs). Citric acid and hydrogen peroxide are introduced as leaching reagents and the leaching of cobalt and lithium with a solution containing C(6)H(8)O(7) x H(2)O is investigated. When both C(6)H(8)O(7) x H(2)O and H(2)O(2) are used an effective recovery of Li and Co as their respective citrates is possible. The leachate is characterized by scanning electron micrography (SEM) and X-ray diffraction (XRD). The proposed procedure includes the mechanical separation of metal-containing particles and a chemical leaching process. Conditions for achieving a recovery of more than 90% Co and nearly 100% Li are achieved experimentally by varying the concentrations of leachant, time and temperature of the reaction as well as the starting solid-to-liquid ratio. Leaching with 1.25 M citric acid, 1.0 vol.% hydrogen peroxide and a S:L of 20 g L(-1) with agitation at 300 rpm in a batch extractor results in a highly efficient recovery of the metals within 30 min of the processing time at 90 degrees C. This hydrometallurgical process is found to be simple, environmentally friendly and adequate for the recovery of valuable metals from spent LIBs.

Atomically dispersed Zn-N-C nanomaterials are promising platinum-free catalysts for the oxygen reduction reaction (ORR). However, the fabrication of Zn-N-C catalysts with a high Zn loading remains a formidable challenge owing to the high volatility of the Zn precursor during high-temperature annealing. Herein, we report that an atomically dispersed Zn-N-C catalyst with an ultrahigh Zn loading of 9.33 wt % could be successfully prepared by simply adopting a very low annealing rate of 1° min-1 . The Zn-N-C catalyst exhibited comparable ORR activity to that of Fe-N-C catalysts, and significantly better ORR stability than Fe-N-C catalysts in both acidic and alkaline media. Further experiments and DFT calculations demonstrated that the Zn-N-C catalyst was less susceptible to protonation than the corresponding Fe-N-C catalyst in an acidic medium. DFT calculations revealed that the Zn-N4 structure is more electrochemically stable than the Fe-N4 structure during the ORR process.

The monoclonal antibody Ki-67 detects a human nuclear antigen that is present in proliferating cells, but absent in quiescent cells. The aim of this study was to characterize the Ki-67 antigen by means of immunobiochemical and molecular biology techniques. Enzymatic digestion experiments showed that this antigen is highly susceptible to protease treatment, and the antigen cannot be extracted by 0.1 normal HCl, indicating that Ki-67 antigen is a nonhistone protein. Immunoblot analysis of cell lysates with Ki-67 showed a double band with apparent molecular weights of 395 kd and 345 kd, regardless of whether the gels were run under reducing or nonreducing conditions. It is noteworthy that these bands were exclusively detectable in lysates prepared from proliferating cells, whereas they were absent in lysates obtained from quiescent cells. These immunobiochemical data are further substantiated by our molecular cloning approaches. By means of immunocloning with Ki-67, the authors isolated and sequenced several cDNA fragments from lambda gt11 libraries. A 1095-bp fragment gave a strong hybridization signal at 7.5 to 9.5 kb in Northern blot analysis with RNA prepared from proliferating cells, whereas it was negative with RNA prepared from quiescent cells. This cDNA fragment could be bacterially expressed, and in subsequent immunoblot analysis Ki-67 reacted exclusively with those fusion proteins that were derived from bacteria containing the insert in the right reading frame.

Pseudomonas aeruginosa is a Gram-negative bacterium that causes opportunistic infections in immunocompromised individuals. P. aeruginosa employs a type III secretion system to inject effector molecules into the cytoplasm of the host cell. This interaction with the host cell leads to inflammatory responses that eventually result in cell death. We show that infection of macrophages with P. aeruginosa results in activation of caspase-1 in an IPAF-dependent, but flagellin-independent, manner. Macrophages deficient in IPAF or caspase-1 were markedly resistant to P. aeruginosa-induced cell death and release of the proinflammatory cytokine interleukin (IL)-1beta. A subset of P. aeruginosa isolates express the effector molecule exoenzyme U (ExoU), which we demonstrate is capable of inhibiting caspase-1-driven proinflammatory cytokine production. This study shows a key role for IPAF and capase-1 in innate immune responses to the pathogen P. aeruginosa, and also demonstrates that virulent ExoU-expressing strains of P. aeruginosa can circumvent this innate immune response.

An approach is evaluated for retrieval of land surface parameters (soil moisture, vegetation water content, and surface temperature) using satellite microwave radiometer data in the 6-18 GHz frequency range. The approach is applicable to data that will be acquired by the Advanced Microwave Scanning Radiometer (AMSR), planned for launch on the Japanese Advanced Earth Observing Satellite (ADEOS)-II and Earth Observing System (EOS) PM-1 platforms in 1999 and 2000, respectively. The retrieval method is based on a radiative transfer (RT) model for land-surface and atmospheric emission, with model coefficients that can be tuned over specific calibration regions and applied globally. The method uses an iterative, least-squares algorithm, based on six channels of radiometric data. Simulations using this algorithm indicate that, for an assumed sensor noise of 0.3 K in all channels, soil moisture and vegetation water content retrieval accuracies of 0.06 g cm/sup -3/ and 0.15 kg m/sup -2/, respectively, should be achievable in regions of vegetation water content less than approximately 1.5 kg m/sup -2/. A surface temperature accuracy of 2 C should be achievable, except for bare soils, where discrimination between moisture and temperature variability is difficult using this algorithm. These accuracies are for retrievals averaged over the sensor footprint, and they exclude conditions of precipitation, open water, snow cover, frozen ground, or high topographic relief within the footprint. The algorithm has been tested using data from the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) for the years 1982-1985, over the African Sahel, and the retrieval results compared to output from an operational numerical weather prediction model.

Many ad hoc routing protocols are based on some variant of flooding. Despite various optimizations of flooding, many routing messages are propagated unnecessarily. We propose a gossiping-based approach, where each node forwards a message with some probability, to reduce the overhead of the routing protocols. Gossiping exhibits bimodal behavior in sufficiently large networks: in some executions, the gossip dies out quickly and hardly any node gets the message; in the remaining executions, a substantial fraction of the nodes gets the message. The fraction of executions in which most nodes get the message depends on the gossiping probability and the topology of the network. In the networks we have considered, using gossiping probability between 0.6 and 0.8 suffices to ensure that almost every node gets the message in almost every execution. For large networks, this simple gossiping protocol uses up to 35% fewer messages than flooding, with improved performance. Gossiping can also be combined with various optimizations of flooding to yield further benefits. Simulations show that adding gossiping to AODV results in significant performance improvement, even in networks as small as 150 nodes. Our results suggest that the improvement should be even more significant in larger networks

Realistic quantum mechanical systems are always exposed to an external environment. The presence of the environment often gives rise to a Markovian process in which the system loses information to its surroundings. However, many quantum systems exhibit a pronounced non-Markovian behavior in which there is a flow of information from the environment back to the system, signifying the presence of quantum memory effects [1-5]. The environment is usually composed of a large number of degrees of freedom which are difficult to control, but some sophisticated schemes for modifying the environment have been developed [6]. The physical realization and control of dynamical processes in open quantum systems plays a decisive role, for example, in recent proposals for the generation of entangled states [7-9], for schemes of dissipative quantum computation [10], for the design of quantum memories [11] and for the enhancement of the efficiency in quantum metrology [12]. Here we report an experiment which allows through selective preparation of the initial environmental states to drive the open system from the Markovian to the non-Markovian regime, to control the information flow between the system and the environment, and to determine the degree of non-Markovianity by direct measurements on the open system.

The mechanisms responsible for the establishment of physical domains in metazoan chromosomes are poorly understood. Here we find that physical domains in Drosophila chromosomes are demarcated at regions of active transcription and high gene density that are enriched for transcription factors and specific combinations of insulator proteins. Physical domains contain different types of chromatin defined by the presence of specific proteins and epigenetic marks, with active chromatin preferentially located at the borders and silenced chromatin in the interior. Domain boundaries participate in long-range interactions that may contribute to the clustering of regions of active or silenced chromatin in the nucleus. Analysis of transgenes suggests that chromatin is more accessible and permissive to transcription at the borders than inside domains, independent of the presence of active or silencing histone modifications. These results suggest that the higher-order physical organization of chromatin may impose an additional level of regulation over classical epigenetic marks.

To characterize IL-17-producing cells, a newly defined T helper cell subset with potent pro-inflammatory properties, in hepatocellular carcinoma (HCC) and to determine their prognostic values.One hundred and seventy-eight HCC patients were enrolled randomly. Distribution and phenotypic features of IL-17-producing cells were determined by flow cytometry and/or immunohistochemistry.Compared with corresponding non-tumor regions, the levels of Th17 cells were significantly increased in tumors of HCC patients (P<0.001). Most intratumoral Th17 cells exhibited an effector memory phenotype with increased expression of CCR4 and CCR6. Intratumoral IL-17-producing cell density was associated with overall survival (OS, P=0.001) and disease-free survival (DFS, P=0.001) in HCC patients. Multivariate Cox analysis revealed that intratumoral IL-17-producing cell density was an independent prognostic factor for OS (HR=2.351, P=0.009) and DFS (HR=2.256, P=0.002). Moreover, the levels of intratumoral Th17 cells were positively correlated with microvessel density in tumors (r=0.616, P=0.001).Accumulation of intratumoral IL-17-producing cells may promote tumor progression through fostering angiogenesis, and intratumoral IL-17-producing cell could serve as a potential prognostic marker and a novel therapeutic target for HCC.

Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.

Automatic crack detection from images of various scenes is a useful and challenging task in practice. In this paper, we propose a deep hierarchical convolutional neural network (CNN), called as DeepCrack, to predict pixel-wise crack segmentation in an end-to-end method. DeepCrack consists of the extended Fully Convolutional Networks (FCN) and the Deeply-Supervised Nets (DSN). During the training, the elaborately designed model learns and aggregates multi-scale and multi-level features from the low convolutional layers to the high-level convolutional layers, which is different from the standard approaches of only using the last convolutional layer. DSN provides integrated direct supervision for features of each convolutional stage. We apply both guided filtering and Conditional Random Fields (CRFs) methods to refine the final prediction results. A benchmark dataset consisting of 537 images with manual annotation maps are built to verify the effectiveness of our proposed method. Our method achieved state-of-the-art performances on the proposed dataset (mean I/U of 85.9, best F-score of 86.5, and 0.1 s per image).

The IL-23/IL-17 and IL-12/IFN-gamma cytokine pathways have a role in chronic autoimmunity, which is considered mainly a dysfunction of adaptive immunity. The extent to which they contribute to innate immunity is, however, unknown. We used a mouse model of acute kidney ischemia-reperfusion injury (IRI) to test the hypothesis that early production of IL-23 and IL-12 following IRI activates downstream IL-17 and IFN-gamma signaling pathways and promotes kidney inflammation. Deficiency in IL-23, IL-17A, or IL-17 receptor (IL-17R) and mAb neutralization of CXCR2, the p19 subunit of IL-23, or IL-17A attenuated neutrophil infiltration in acute kidney IRI in mice. We further demonstrate that IL-17A produced by GR-1+ neutrophils was critical for kidney IRI in mice. Activation of the IL-12/IFN-gamma pathway and NKT cells by administering alpha-galactosylceramide-primed bone marrow-derived DCs increased IFN-gamma production following moderate IRI in WT mice but did not exacerbate injury or enhance IFN-gamma production in either Il17a-/- or Il17r-/- mice, which suggested that IL-17 signaling was proximal to IFN-gamma signaling. This was confirmed by the finding that IFN-gamma administration reversed the protection seen in Il17a-/- mice subjected to IRI, whereas IL-17A failed to reverse protection in Ifng-/- mice. These results demonstrate that the innate immune component of kidney IRI requires dual activation of the IL-12/IFN-gamma and IL-23/IL-17 signaling pathways and that neutrophil production of IL-17A is upstream of IL-12/IFN-gamma. These mechanisms might contribute to reperfusion injury in other organs.

To identify single-nucleotide polymorphisms (SNPs) associated with risk and age at onset of Alzheimer disease (AD) in a genomewide association study of 469 438 SNPs.Case-control study with replication.Memory referral clinics in Canada and the United Kingdom.The hypothesis-generating data set consisted of 753 individuals with AD by National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association criteria recruited from 9 memory referral clinics in Canada and 736 ethnically matched control subjects; control subjects were recruited from nonbiological relatives, friends, or spouses of the patients and did not exhibit cognitive impairment by history or cognitive testing. The follow-up data set consisted of 418 AD cases and 249 nondemented control cases from the United Kingdom Medical Research Council Genetic Resource for Late-Onset AD recruited from clinics at Cardiff University, Cardiff, Wales, and King's College London, London, England.Odds ratios and 95% confidence intervals for association of SNPs with AD by logistic regression adjusted for age, sex, education, study site, and French Canadian ancestry (for the Canadian data set). Hazard ratios and 95% confidence intervals from Cox proportional hazards regression for age at onset with similar covariate adjustments.Unadjusted, SNP RS4420638 within APOC1 was strongly associated with AD due entirely to linkage disequilibrium with APOE. In the multivariable adjusted analyses, 3 SNPs within the top 120 by P value in the logistic analysis and 1 in the Cox analysis of the Canadian data set provided additional evidence for association at P< .05 within the United Kingdom Medical Research Council data set: RS7019241 (GOLPH2), RS10868366 (GOLPH2), RS9886784 (chromosome 9), and RS10519262 (intergenic between ATP8B4 and SLC27A2).Our genomewide association analysis again identified the APOE linkage disequilibrium region as the strongest genetic risk factor for AD. This could be a consequence of the coevolution of more than 1 susceptibility allele, such as APOC1, in this region. We also provide new evidence for additional candidate genetic risk factors for AD that can be tested in further studies.

Previous studies have shown that common human coronavirus might be neurotropic, although it was first isolated as a pathogen of the respiratory tract. We noticed that a few patients with severe acute respiratory syndrome (SARS) experienced central nervous symptoms during the course of illness. In the present study, we isolated a SARS coronavirus strain from a brain tissue specimen obtained from a patient with SARS with significant central nervous symptoms.Using transmission electronic microscopy and nested reverse transcription-polymerase chain reaction, the causative pathogen was identified in cultures of a brain tissue specimen obtained from the patient with SARS. Histopathologic examination of the brain tissue was performed using the methods of immunohistochemistry analysis and double immunofluorescence staining. Fifteen cytokines and chemokines were detected in the blood of the patient with SARS by means of a bead-based multiassay system.A fragment specific for SARS human coronavirus was amplified from cultures of the brain suspension, and transmission electronic microscopy revealed the presence of an enveloped virus morphologically compatible with a coronavirus isolated in the cultures. Pathologic examination of the brain tissue revealed necrosis of neuron cells and broad hyperplasia of gliocytes. Immunostaining demonstrated that monokine induced by interferon- gamma (Mig) was expressed in gliocytes with the infiltration of CD68+ monocytes/macrophages and CD3+ T lymphocytes in the brain mesenchyme. Cytokine/chemokine assay revealed that levels of interferon- gamma -inducible protein 10 and Mig in the blood were highly elevated, although the levels of other cytokines and chemokines were close to normal.This study provides direct evidence that SARS human coronavirus is capable of infecting the central nervous system, and that Mig might be involved in the brain immunopathology of SARS.

Type 2 diabetes (T2D) is a heterogeneous complex disease affecting more than 29 million Americans alone with a rising prevalence trending toward steady increases in the coming decades. Thus, there is a pressing clinical need to improve early prevention and clinical management of T2D and its complications. Clinicians have understood that patients who carry the T2D diagnosis have a variety of phenotypes and susceptibilities to diabetes-related complications. We used a precision medicine approach to characterize the complexity of T2D patient populations based on high-dimensional electronic medical records (EMRs) and genotype data from 11,210 individuals. We successfully identified three distinct subgroups of T2D from topology-based patient-patient networks. Subtype 1 was characterized by T2D complications diabetic nephropathy and diabetic retinopathy; subtype 2 was enriched for cancer malignancy and cardiovascular diseases; and subtype 3 was associated most strongly with cardiovascular diseases, neurological diseases, allergies, and HIV infections. We performed a genetic association analysis of the emergent T2D subtypes to identify subtype-specific genetic markers and identified 1279, 1227, and 1338 single-nucleotide polymorphisms (SNPs) that mapped to 425, 322, and 437 unique genes specific to subtypes 1, 2, and 3, respectively. By assessing the human disease-SNP association for each subtype, the enriched phenotypes and biological functions at the gene level for each subtype matched with the disease comorbidities and clinical differences that we identified through EMRs. Our approach demonstrates the utility of applying the precision medicine paradigm in T2D and the promise of extending the approach to the study of other complex, multifactorial diseases.

The patterning of skeletal muscle is thought to depend upon signals provided by motor neurons. We show that AChR gene expression and AChR clusters are concentrated in the central region of embryonic skeletal muscle in the absence of innervation. Neurally derived Agrin is dispensable for this early phase of AChR expression, but MuSK, a receptor tyrosine kinase activated by Agrin, is required to establish this AChR prepattern. The zone of AChR expression in muscle lacking motor axons is wider than normal, indicating that neural signals refine this muscle-autonomous prepattern. Neuronal Neuregulin-1, however, is not involved in this refinement process, nor indeed in synapse-specific AChR gene expression. Our results demonstrate that AChR expression is patterned in the absence of innervation, raising the possibility that similarly prepatterned muscle-derived cues restrict axon growth and initiate synapse formation.

The outbreak of COVID-19 has spreaded rapidly across the world. To control the rapid dispersion of the virus, China has imposed national lockdown policies to practise social distancing. This has led to reduced human activities and hence primary air pollutant emissions, which caused improvement of air quality as a side-product. To investigate the air quality changes during the COVID-19 lockdown over the YRD Region, we apply the WRF-CAMx modelling system together with monitoring data to investigate the impact of human activity pattern changes on air quality. Results show that human activities were lowered significantly during the period: industrial operations, VKT, constructions in operation, etc. were significantly reduced, leading to lowered SO2, NOx, PM2.5 and VOCs emissions by approximately 16–26%, 29–47%, 27–46% and 37–57% during the Level I and Level II response periods respectively. These emission reduction has played a significant role in the improvement of air quality. Concentrations of PM2.5, NO2 and SO2 decreased by 31.8%, 45.1% and 20.4% during the Level I period; and 33.2%, 27.2% and 7.6% during the Level II period compared with 2019. However, ozone did not show any reduction and increased greatly. Our results also show that even during the lockdown, with primary emissions reduction of 15%–61%, the daily average PM2.5 concentrations range between 15 and 79 μg m−3, which shows that background and residual pollutions are still high. Source apportionment results indicate that the residual pollution of PM2.5 comes from industry (32.2–61.1%), mobile (3.9–8.1%), dust (2.6–7.7%), residential sources (2.1–28.5%) in YRD and 14.0–28.6% contribution from long-range transport coming from northern China. This indicates that in spite of the extreme reductions in primary emissions, it cannot fully tackle the current air pollution. Re-organisation of the energy and industrial strategy together with trans-regional joint-control for a full long-term air pollution plan need to be further taken into account.

The need of a medium access control (MAC) protocol for an efficient broadcast service is of great importance to support the high-priority safety applications in vehicular ad hoc networks (VANETs). This paper introduces VeMAC, a novel multichannel TDMA MAC protocol proposed specifically for a VANET scenario. The VeMAC supports efficient one-hop and multihop broadcast services on the control channel by using implicit acknowledgments and eliminating the hidden terminal problem. The protocol reduces transmission collisions due to node mobility on the control channel by assigning disjoint sets of time slots to vehicles moving in opposite directions and to road side units. Analysis and simulation results in highway and city scenarios are presented to evaluate the performance of VeMAC and compare it with ADHOC MAC, an existing TDMA MAC protocol for VANETs. It is shown that, due to its ability to decrease the rate of transmission collisions, the VeMAC protocol can provide significantly higher throughput on the control channel than ADHOC MAC.

Abstract N 6-Methyladenosine (m6A) is the most abundant RNA modification in mammal mRNAs and increasing evidence suggests the key roles of m6A in human tumorigenesis. However, whether m6A, especially its ‘reader’ YTHDF1, targets a gene involving in protein translation and thus affects overall protein production in cancer cells is largely unexplored. Here, using multi-omics analysis for ovarian cancer, we identified a novel mechanism involving EIF3C, a subunit of the protein translation initiation factor EIF3, as the direct target of the YTHDF1. YTHDF1 augments the translation of EIF3C in an m6A-dependent manner by binding to m6A-modified EIF3C mRNA and concomitantly promotes the overall translational output, thereby facilitating tumorigenesis and metastasis of ovarian cancer. YTHDF1 is frequently amplified in ovarian cancer and up-regulation of YTHDF1 is associated with the adverse prognosis of ovarian cancer patients. Furthermore, the protein but not the RNA abundance of EIF3C is increased in ovarian cancer and positively correlates with the protein expression of YTHDF1 in ovarian cancer patients, suggesting modification of EIF3C mRNA is more relevant to its role in cancer. Collectively, we identify the novel YTHDF1-EIF3C axis critical for ovarian cancer progression which can serve as a target to develop therapeutics for cancer treatment.

Hybrid supercapacitors (HSCs) assembled with battery-type and capacitive-type electrodes show combined advantages from both batteries and electric double-layer capacitors, rendering them promising advanced energy storage devices for commercial applications. However, electrochemical performances of HSCs towards high-rate and long-life energy storage are restricted by battery-type materials because of sluggish ion/electron diffusion and inferior structural stability. Herein, current research progress of transition metal based battery-type materials in hybrid supercapacitors is reviewed. We firstly introduce the hybridization principles, development requirements and material classification of HSCs. The battery-type materials are then categorized into intercalation-type and conversion-type electrodes with detailed review of materials and strategies to tune their energy storage performances. Finally, conclusive remarks and opinions for future development of high performance HSCs are proposed with the intention to provide some clues for build-up of high rate and long life energy storage systems.

We examined and compared PM2.5 concentrations in urban and the surrounding regions, and further investigated the impact of urbanization on urban PM2.5 concentrations at the Chinese prefectures. Annual PM2.5 concentrations in most prefectures were greater than 10 μg/m3, the air quality guideline of the World Health Organization. Those prefectures were mainly distributed along the east coast and southeast of Sichuan province; The urban PM2.5 concentrations (UrbanPM2.5) in 85 cities were greater than (>10 μg/m3) those in the surrounding area. Those cities were mainly located in the Beijing–Sichuan and Shanghai–Guangxi belts. In addition, UrbanPM2.5 was less than (<0 μg/m3) that in surrounding areas in only 41 prefectures, which were located in western China or nearby mega cities; Significant positive correlations were found between UrbanPM2.5 and urban population (R2 = 0.99, P < 0.05), and between UrbanPM2.5 and urban second industry fraction (R2 = 0.71, P < 0.05), suggesting that urbanization had considerable impact on PM2.5 concentrations.

We have designed and synthesized a polyaniline (PANI)-decorated Pt/C@PANI core–shell catalyst that shows enhanced catalyst activity and durability compared with nondecorated Pt/C. The experimental results demonstrate that the activity for the oxygen reduction reaction strongly depends on the thickness of the PANI shell and that the greatest enhancement in catalytic properties occurs at a thickness of 5 nm, followed by 2.5, 0, and 14 nm. Pt/C@PANI also demonstrates significantly improved stability compared with that of the unmodified Pt/C catalyst. The high activity and stability of the Pt/C@PANI catalyst is ascribed to its novel PANI-decorated core–shell structure, which induces both electron delocalization between the Pt d orbitals and the PANI π-conjugated ligand and electron transfer from Pt to PANI. The stable PANI shell also protects the carbon support from direct exposure to the corrosive environment.

Immunotherapies have led to substantial changes in cancer treatment and have been a persistently popular topic in cancer research because they tremendously improve the efficacy of treatment and survival of individuals with various cancer types. However, only a small proportion of patients are sensitive to immunotherapy, and specific biomarkers are urgently needed to separate responders from nonresponders. Mismatch repair pathways play a vital role in identifying and repairing mismatched bases during DNA replication and genetic recombination in normal and cancer cells. Defects in DNA mismatch repair proteins and subsequent microsatellite instability-high lead to the accumulation of mutation loads in cancer-related genes and the generation of neoantigens, which stimulate the anti-tumor immune response of the host. Mismatch repair deficiency/microsatellite instability-high represents a good prognosis in early colorectal cancer settings without adjuvant treatment and a poor prognosis in patients with metastasis. Several clinical trials have demonstrated that mismatch repair deficiency or microsatellite instability-high is significantly associated with long-term immunotherapy-related responses and better prognosis in colorectal and noncolorectal malignancies treated with immune checkpoint inhibitors. To date, the anti-programmed cell death-1 inhibitor pembrolizumab has been approved for mismatch repair deficiency/microsatellite instability-high refractory or metastatic solid tumors, and nivolumab has been approved for colorectal cancer patients with mismatch repair deficiency/microsatellite instability-high. This is the first time in the history of cancer therapy that the same biomarker has been used to guide immune therapy regardless of tumor type. This review summarizes the features of mismatch repair deficiency/microsatellite instability-high, its relationship with programmed death-ligand 1/programmed cell death-1, and the recent advances in predicting immunotherapy efficacy.

Deep learning (DL) defines a new data-driven programming paradigm that constructs the internal system logic of a crafted neuron network through a set of training data. We have seen wide adoption of DL in many safety-critical scenarios. However, a plethora of studies have shown that the state-of-the-art DL systems suffer from various vulnerabilities which can lead to severe consequences when applied to real-world applications. Currently, the testing adequacy of a DL system is usually measured by the accuracy of test data. Considering the limitation of accessible high quality test data, good accuracy performance on test data can hardly provide confidence to the testing adequacy and generality of DL systems. Unlike traditional software systems that have clear and controllable logic and functionality, the lack of interpretability in a DL system makes system analysis and defect detection difficult, which could potentially hinder its real-world deployment. In this paper, we propose DeepGauge, a set of multi-granularity testing criteria for DL systems, which aims at rendering a multi-faceted portrayal of the testbed. The in-depth evaluation of our proposed testing criteria is demonstrated on two well-known datasets, five DL systems, and with four state-of-the-art adversarial attack techniques against DL. The potential usefulness of DeepGauge sheds light on the construction of more generic and robust DL systems.

Two-dimensional birnessite has attracted attention for electrochemical energy storage because of the presence of redox active Mn4+/Mn3+ ions and spacious interlayer channels available for ions diffusion. However, current strategies are largely limited to enhancing the electrical conductivity of birnessite. One key limitation affecting the electrochemical properties of birnessite is the poor utilization of the MnO6 unit. Here, we assemble β-MnO2/birnessite core–shell structure that exploits the exposed crystal face of β-MnO2 as the core and ultrathin birnessite sheets that have the structure advantage to enhance the utilization efficiency of the Mn from the bulk. Our birnessite that has sheets parallel to each other is found to have unusual crystal structure with interlayer spacing, Mn(III)/Mn(IV) ratio and the content of the balancing cations differing from that of the common birnessite. The substrate directed growth mechanism is carefully investigated. The as-prepared core–shell nanostructures enhance the exposed surface area of birnessite and achieve high electrochemical performances (for example, 657 F g–1 in 1 M Na2SO4 electrolyte based on the weight of parallel birnessite) and excellent rate capability over a potential window of up to 1.2 V. This strategy opens avenues for fundamental studies of birnessite and its properties and suggests the possibility of its use in energy storage and other applications. The potential window of an asymmetric supercapacitor that was assembled with this material can be enlarged to 2.2 V (in aqueous electrolyte) with a good cycling ability.

Ferritin is a spherical molecule composed of 24 subunits of two types, ferritin H chain (FHC) and ferritin L chain (FLC). Ferritin stores iron within cells, but it also circulates and binds specifically and saturably to a variety of cell types. For most cell types, this binding can be mediated by ferritin composed only of FHC (HFt) but not by ferritin composed only of FLC (LFt), indicating that binding of ferritin to cells is mediated by FHC but not FLC. By using expression cloning, we identified human transferrin receptor-1 (TfR1) as an important receptor for HFt with little or no binding to LFt. In vitro, HFt can be precipitated by soluble TfR1, showing that this interaction is not dependent on other proteins. Binding of HFt to TfR1 is partially inhibited by diferric transferrin, but it is hindered little, if at all, by HFE. After binding of HFt to TfR1 on the cell surface, HFt enters both endosomes and lysosomes. TfR1 accounts for most, if not all, of the binding of HFt to mitogen-activated T and B cells, circulating reticulocytes, and all cell lines that we have studied. The demonstration that TfR1 can bind HFt as well as Tf raises the possibility that this dual receptor function may coordinate the processing and use of iron by these iron-binding molecules.

Abstract Nanolayers of Al 2 O 3 and TiO 2 coatings were applied to lithium‐ and manganese‐rich cathode powder Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 using an atomic layer deposition (ALD) method. The ALD coatings exhibited different surface morphologies; the Al 2 O 3 surface film appeared to be uniform and conformal, while the TiO 2 layers appeared as particulates across the material surface. In a Li‐cell, the Al 2 O 3 surface film was stable during repeated charge and discharge, and this improved the cell cycling stability, despite a high surface impedance. The TiO 2 layer was found to be more reactive with Li and formed a Li x TiO 2 interface, which led to a slight increase in cell capacity. However, the repetitive insertion/extraction process for the Li + ions caused erosion of the surface protective TiO 2 film, which led to degradation in cell performance, particularly at high temperature. For cells comprised of the coated Li 1.2 Ni 0.13 Mn 0.54 Co 0.13 O 2 and an anode of meso‐carbon‐micro‐beads (MCMB), the cycling stability introduced by ALD was not enough to overcome the electrochemical instability of MCMB graphite. Therefore, protection of the cathode materials by ALD Al 2 O 3 or TiO 2 can address some of the capacity fading issues related to the Li‐rich cathode at room temperature.

Mitochondria are complex organelles with a highly dynamic distribution and internal organization. Here, we demonstrate that mitofilin, a previously identified mitochondrial protein of unknown function, controls mitochondrial cristae morphology. Mitofilin is enriched in the narrow space between the inner boundary and the outer membranes, where it forms a homotypic interaction and assembles into a large multimeric protein complex. Down-regulation of mitofilin in HeLa cells by using specific small interfering RNA lead to decreased cellular proliferation and increased apoptosis, suggesting abnormal mitochondrial function. Although gross mitochondrial fission and fusion seemed normal, ultrastructural studies revealed disorganized mitochondrial inner membrane. Inner membranes failed to form tubular or vesicular cristae and showed as closely packed stacks of membrane sheets that fused intermittently, resulting in a complex maze of membranous network. Electron microscopic tomography estimated a substantial increase in inner:outer membrane ratio, whereas no cristae junctions were detected. In addition, mitochondria subsequently exhibited increased reactive oxygen species production and membrane potential. Although metabolic flux increased due to mitofilin deficiency, mitochondrial oxidative phosphorylation was not increased accordingly. We propose that mitofilin is a critical organizer of the mitochondrial cristae morphology and thus indispensable for normal mitochondrial function.