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Proton-assisted growth of ultra-flat graphene films 期刊论文
NATURE, 2020, 577 (7789) : 204-+
作者:  Yuan, Guowen;  Lin, Dongjing;  Wang, Yong;  Huang, Xianlei;  Chen, Wang;  Xie, Xuedong;  Zong, Junyu;  Yuan, Qian-Qian;  Zheng, Hang;  Wang, Di;  Xu, Jie;  Li, Shao-Chun;  Zhang, Yi;  Sun, Jian;  Xi, Xiaoxiang;  Gao, Libo
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/03

Graphene films grown by chemical vapour deposition have unusual physical and chemical properties that offer promise for applications such as flexible electronics and high-frequency transistors(1-10). However, wrinkles invariably form during growth because of the strong coupling to the substrate, and these limit the large-scale homogeneity of the film(1-4,11,12). Here we develop a proton-assisted method of chemical vapour deposition to grow ultra-flat graphene films that are wrinkle-free. Our method of proton penetration(13-17) and recombination to form hydrogen can also reduce the wrinkles formed during traditional chemical vapour deposition of graphene. Some of the wrinkles disappear entirely, owing to the decoupling of van der Waals interactions and possibly an increase in distance from the growth surface. The electronic band structure of the as-grown graphene films shows a V-shaped Dirac cone and a linear dispersion relation within the atomic plane or across an atomic step, confirming the decoupling from the substrate. The ultra-flat nature of the graphene films ensures that their surfaces are easy to clean after a wet transfer process. A robust quantum Hall effect appears even at room temperature in a device with a linewidth of 100 micrometres. Graphene films grown by proton-assisted chemical vapour deposition should largely retain their intrinsic performance, and our method should be easily generalizable to other nanomaterials for strain and doping engineering.


  
Millennial-scale hydroclimate control of tropical soil carbon storage 期刊论文
NATURE, 2020, 581 (7806) : 63-+
作者:  Lam, Tommy Tsan-Yuk;  Jia, Na;  Zhang, Ya-Wei;  Shum, Marcus Ho-Hin;  Jiang, Jia-Fu;  Zhu, Hua-Chen;  Tong, Yi-Gang;  Shi, Yong-Xia;  Ni, Xue-Bing;  Liao, Yun-Shi;  Li, Wen-Juan;  Jiang, Bao-Gui;  Wei, Wei;  Yuan, Ting-Ting;  Zheng, Kui;  Cui, Xiao-Ming;  Li, Jie;  Pei, Guang-Qian
收藏  |  浏览/下载:25/0  |  提交时间:2020/05/13

Over the past 18,000 years, the residence time and amount of soil carbon stored in the Ganges-Brahmaputra basin have been controlled by the intensity of Indian Summer Monsoon rainfall, with greater carbon destabilization during wetter, warmer conditions.


The storage of organic carbon in the terrestrial biosphere directly affects atmospheric concentrations of carbon dioxide over a wide range of timescales. Within the terrestrial biosphere, the magnitude of carbon storage can vary in response to environmental perturbations such as changing temperature or hydroclimate(1), potentially generating feedback on the atmospheric inventory of carbon dioxide. Although temperature controls the storage of soil organic carbon at mid and high latitudes(2,3), hydroclimate may be the dominant driver of soil carbon persistence in the tropics(4,5)  however, the sensitivity of tropical soil carbon turnover to large-scale hydroclimate variability remains poorly understood. Here we show that changes in Indian Summer Monsoon rainfall have controlled the residence time of soil carbon in the Ganges-Brahmaputra basin over the past 18,000 years. Comparison of radiocarbon ages of bulk organic carbon and terrestrial higher-plant biomarkers with co-located palaeohydrological records(6) reveals a negative relationship between monsoon rainfall and soil organic carbon stocks on a millennial timescale. Across the deglaciation period, a depletion of basin-wide soil carbon stocks was triggered by increasing rainfall and associated enhanced soil respiration rates. Our results suggest that future hydroclimate changes in tropical regions are likely to accelerate soil carbon destabilization, further increasing atmospheric carbon dioxide concentrations.


  
The water lily genome and the early evolution of flowering plants 期刊论文
NATURE, 2020, 577 (7788) : 79-+
作者:  Zhang, Liangsheng;  Chen, Fei;  Zhang, Xingtan;  Li, Zhen;  Zhao, Yiyong;  Lohaus, Rolf;  Chang, Xiaojun;  Dong, Wei;  Ho, Simon Y. W.;  Liu, Xing;  Song, Aixia;  Chen, Junhao;  Guo, Wenlei;  Wang, Zhengjia;  Zhuang, Yingyu;  Wang, Haifeng;  Chen, Xuequn;  Hu, Juan;  Liu, Yanhui;  Qin, Yuan;  Wang, Kai;  Dong, Shanshan;  Liu, Yang;  Zhang, Shouzhou;  Yu, Xianxian;  Wu, Qian;  Wang, Liangsheng;  Yan, Xueqing;  Jiao, Yuannian;  Kong, Hongzhi;  Zhou, Xiaofan;  Yu, Cuiwei;  Chen, Yuchu;  Li, Fan;  Wang, Jihua;  Chen, Wei;  Chen, Xinlu;  Jia, Qidong;  Zhang, Chi;  Jiang, Yifan;  Zhang, Wanbo;  Liu, Guanhua;  Fu, Jianyu;  Chen, Feng;  Ma, Hong;  Van de Peer, Yves;  Tang, Haibao
收藏  |  浏览/下载:13/0  |  提交时间:2020/07/03

Water lilies belong to the angiosperm order Nymphaeales. Amborellales, Nymphaeales and Austrobaileyales together form the so-called ANA-grade of angiosperms, which are extant representatives of lineages that diverged the earliest from the lineage leading to the extant mesangiosperms(1-3). Here we report the 409-megabase genome sequence of the blue-petal water lily (Nymphaea colorata). Our phylogenomic analyses support Amborellales and Nymphaeales as successive sister lineages to all other extant angiosperms. The N. colorata genome and 19 other water lily transcriptomes reveal a Nymphaealean whole-genome duplication event, which is shared by Nymphaeaceae and possibly Cabombaceae. Among the genes retained from this whole-genome duplication are homologues of genes that regulate flowering transition and flower development. The broad expression of homologues of floral ABCE genes in N. colorata might support a similarly broadly active ancestral ABCE model of floral organ determination in early angiosperms. Water lilies have evolved attractive floral scents and colours, which are features shared with mesangiosperms, and we identified their putative biosynthetic genes in N. colorata. The chemical compounds and biosynthetic genes behind floral scents suggest that they have evolved in parallel to those in mesangiosperms. Because of its unique phylogenetic position, the N. colorata genome sheds light on the early evolution of angiosperms.


  
The combined effect of two westerly jet waveguides on heavy haze in the North China Plain in November and December 2015 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (8) : 4667-4680
作者:  An, Xiadong;  Sheng, Lifang;  Liu, Qian;  Li, Chun;  Gao, Yang;  Li, Jianping
收藏  |  浏览/下载:11/0  |  提交时间:2020/05/13
Dehydration and low ozone in the tropopause layer over the Asian monsoon caused by tropical cyclones: Lagrangian transport calculations using ERA-Interim and ERA5 reanalysis data 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (7) : 4133-4152
作者:  Li, Dan;  Vogel, Baerbel;  Mueller, Rolf;  Bian, Jianchun;  Guenther, Gebhard;  Ploeger, Felix;  Li, Qian;  Zhang, Jinqiang;  Bai, Zhixuan;  Vomel, Holger;  Riese, Martin
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/02
Sources of volatile organic compounds and policy implications for regional ozone pollution control in an urban location of Nanjing, East China 期刊论文
ATMOSPHERIC CHEMISTRY AND PHYSICS, 2020, 20 (6) : 3905-3919
作者:  Zhao, Qiuyue;  Bi, Jun;  Liu, Qian;  Ling, Zhenghao;  Shen, Guofeng;  Chen, Feng;  Qiao, Yuezhen;  Li, Chunyan;  Ma, Zongwei
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/02
CRISPR screen in regulatory T cells reveals modulators of Foxp3 期刊论文
NATURE, 2020
作者:  Xu, Daqian;  Wang, Zheng;  Xia, Yan;  Shao, Fei;  Xia, Weiya;  Wei, Yongkun;  Li, Xinjian;  Qian, Xu;  Lee, Jong-Ho;  Du, Linyong;  Zheng, Yanhua;  Lv, Guishuai;  Leu, Jia-shiun;  Wang, Hongyang;  Xing, Dongming;  Liang, Tingbo;  Hung, Mien-Chie;  Lu, Zhimin
收藏  |  浏览/下载:33/0  |  提交时间:2020/07/03

Regulatory T (T-reg) cells are required to control immune responses and maintain homeostasis, but are a significant barrier to antitumour immunity(1). Conversely, T-reg instability, characterized by loss of the master transcription factor Foxp3 and acquisition of proinflammatory properties(2), can promote autoimmunity and/or facilitate more effective tumour immunity(3,4). A comprehensive understanding of the pathways that regulate Foxp3 could lead to more effective T-reg therapies for autoimmune disease and cancer. The availability of new functional genetic tools has enabled the possibility of systematic dissection of the gene regulatory programs that modulate Foxp3 expression. Here we developed a CRISPR-based pooled screening platform for phenotypes in primary mouse T-reg cells and applied this technology to perform a targeted loss-of-function screen of around 500 nuclear factors to identify gene regulatory programs that promote or disrupt Foxp3 expression. We identified several modulators of Foxp3 expression, including ubiquitin-specific peptidase 22 (Usp22) and ring finger protein 20 (Rnf20). Usp22, a member of the deubiquitination module of the SAGA chromatin-modifying complex, was revealed to be a positive regulator that stabilized Foxp3 expression  whereas the screen suggested that Rnf20, an E3 ubiquitin ligase, can serve as a negative regulator of Foxp3. T-reg-specific ablation of Usp22 in mice reduced Foxp3 protein levels and caused defects in their suppressive function that led to spontaneous autoimmunity but protected against tumour growth in multiple cancer models. Foxp3 destabilization in Usp22-deficient T-reg cells could be rescued by ablation of Rnf20, revealing a reciprocal ubiquitin switch in T-reg cells. These results reveal previously unknown modulators of Foxp3 and demonstrate a screening method that can be broadly applied to discover new targets for T-reg immunotherapies for cancer and autoimmune disease.


A CRISPR-based screening platform was used to identify previously uncharacterized genes that regulate the regulatory T cell-specific master transcription factor Foxp3, indicating that this screening method may be broadly applicable for the discovery of other genes involved in autoimmunity and immune responses to cancer.


  
Rapid reconstruction of SARS-CoV-2 using a synthetic genomics platform 期刊论文
NATURE, 2020
作者:  Touat, Mehdi;  Li, Yvonne Y.;  Boynton, Adam N.;  Spurr, Liam F.;  Iorgulescu, J. Bryan;  Bohrson, Craig L.;  Cortes-Ciriano, Isidro;  Birzu, Cristina;  Geduldig, Jack E.;  Pelton, Kristine;  Lim-Fat, Mary Jane;  Pal, Sangita;  Ferrer-Luna, Ruben;  Ramkissoon, Shakti H.;  Dubois, Frank;  Bellamy, Charlotte;  Currimjee, Naomi;  Bonardi, Juliana;  Qian Kenin;  Ho, Patricia;  Malinowski, Seth;  Taquet, Leon;  Jones, Robert E.;  Shetty, Aniket;  Chow, Kin-Hoe;  Sharaf, Radwa;  Pavlick, Dean;  Albacker, Lee A.;  Younan, Nadia;  Baldini, Capucine;  Verreault, Maite;  Giry, Marine;  Guillerm, Erell;  Ammari, Samy;  Beuvon, Frederic;  Mokhtari, Karima;  Alentorn, Agusti;  Dehais, Caroline;  Houillier, Caroline;  Laigle-Donadey, Florence;  Psimaras, Dimitri;  Lee, Eudocia Q.;  Nayak, Lakshmi;  McFaline-Figueroa, J. Ricardo;  Carpentier, Alexandre;  Cornu, Philippe;  Capelle, Laurent;  Mathon, Bertrand;  Barnholtz-Sloan, Jill S.;  Chakravarti, Arnab;  Bi, Wenya Linda;  Chiocca, E. Antonio;  Fehnel, Katie Pricola;  Alexandrescu, Sanda;  Chi, Susan N.;  Haas-Kogan, Daphne;  Batchelor, Tracy T.;  Frampton, Garrett M.;  Alexander, Brian M.;  Huang, Raymond Y.;  Ligon, Azra H.;  Coulet, Florence;  Delattre, Jean-Yves;  Hoang-Xuan, Khe;  Meredith, David M.;  Santagata, Sandro;  Duval, Alex;  Sanson, Marc;  Cherniack, Andrew D.;  Wen, Patrick Y.;  Reardon, David A.;  Marabelle, Aurelien;  Park, Peter J.;  Idbaih, Ahmed;  Beroukhim, Rameen;  Bandopadhayay, Pratiti;  Bielle, Franck;  Ligon, Keith L.
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/03

Reverse genetics has been an indispensable tool to gain insights into viral pathogenesis and vaccine development. The genomes of large RNA viruses, such as those from coronaviruses, are cumbersome to clone and manipulate inEscherichia coliowing to the size and occasional instability of the genome(1-3). Therefore, an alternative rapid and robust reverse-genetics platform for RNA viruses would benefit the research community. Here we show the full functionality of a yeast-based synthetic genomics platform to genetically reconstruct diverse RNA viruses, including members of theCoronaviridae,FlaviviridaeandPneumoviridaefamilies. Viral subgenomic fragments were generated using viral isolates, cloned viral DNA, clinical samples or synthetic DNA, and these fragments were then reassembled in one step inSaccharomyces cerevisiaeusing transformation-associated recombination cloning to maintain the genome as a yeast artificial chromosome. T7 RNA polymerase was then used to generate infectious RNA to rescue viable virus. Using this platform, we were able to engineer and generate chemically synthesized clones of the virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)(4), which has caused the recent pandemic of coronavirus disease (COVID-19), in only a week after receipt of the synthetic DNA fragments. The technical advance that we describe here facilitates rapid responses to emerging viruses as it enables the real-time generation and functional characterization of evolving RNA virus variants during an outbreak.


A yeast-based synthetic genomics platform is used to reconstruct and characterize large RNA viruses from synthetic DNA fragments  this technique will facilitate the rapid analysis of RNA viruses, such as SARS-CoV-2, during an outbreak.


  
Intraplate volcanism originating from upwelling hydrous mantle transition zone 期刊论文
NATURE, 2020
作者:  Calabrese, Claudia;  Davidson, Natalie R.;  Demircioglu, Deniz;  Fonseca, Nuno A.;  He, Yao;  Kahles, Andre;  Kjong-Van Lehmann;  Liu, Fenglin;  Shiraishi, Yuichi;  Soulette, Cameron M.;  Urban, Lara;  Greger, Liliana;  Li, Siliang;  Liu, Dongbing;  Perry, Marc D.;  Xiang, Qian;  Zhang, Fan;  Zhang, Junjun;  Bailey, Peter;  Erkek, Serap;  Hoadley, Katherine A.;  Hou, Yong;  Huska, Matthew R.;  Kilpinen, Helena;  Korbel, Jan O.;  Marin, Maximillian G.;  Markowski, Julia;  Nandi, Tannistha;  Pan-Hammarstrom, Qiang;  Pedamallu, Chandra Sekhar;  Siebert, Reiner;  Stark, Stefan G.;  Su, Hong;  Tan, Patrick;  Waszak, Sebastian M.;  Yung, Christina;  Zhu, Shida;  Awadalla, Philip;  Creighton, Chad J.;  Meyerson, Matthew;  Ouellette, B. F. Francis;  Wu, Kui;  Yang, Huanming;  Brazma, Alvis;  Brooks, Angela N.;  Goke, Jonathan;  Raetsch, Gunnar;  Schwarz, Roland F.;  Stegle, Oliver;  Zhang, Zemin
收藏  |  浏览/下载:75/0  |  提交时间:2020/05/13

Most magmatism occurring on Earth is conventionally attributed to passive mantle upwelling at mid-ocean ridges, to slab devolatilization at subduction zones, or to mantle plumes. However, the widespread Cenozoic intraplate volcanism in northeast China(1-3) and the young petit-spot volcanoes(4-7) offshore of the Japan Trench cannot readily be associated with any of these mechanisms. In addition, the mantle beneath these types of volcanism is characterized by zones of anomalously low seismic velocity above and below the transition zone(8-12) (a mantle level located at depths between 410 and 660 kilometres). A comprehensive interpretation of these phenomena is lacking. Here we show that most (or possibly all) of the intraplate and petit-spot volcanism and low-velocity zones around the Japanese subduction zone can be explained by the Cenozoic interaction of the subducting Pacific slab with a hydrous mantle transition zone. Numerical modelling indicates that 0.2 to 0.3 weight per cent of water dissolved in mantle minerals that are driven out from the transition zone in response to subduction and retreat of a tectonic plate is sufficient to reproduce the observations. This suggests that a critical amount of water may have accumulated in the transition zone around this subduction zone, as well as in others of the Tethyan tectonic belt(13) that are characterized by intraplate or petit-spot volcanism and low-velocity zones in the underlying mantle.


The widespread intraplate volcanism in northeast China and the unusual '  petit-spot'  volcanoes offshore Japan could have resulted from the interaction of the subducting Pacific slab with a hydrous mantle transition zone.


  
The measurement of ice nucleating particles at Tai'an city in East China 期刊论文
ATMOSPHERIC RESEARCH, 2020, 232
作者:  Jiang, Hui;  Yin, Yan;  Chen, Kui;  Chen, Qian;  He, Chuan;  Sun, Li
收藏  |  浏览/下载:5/0  |  提交时间:2020/07/02
Ice nucleating particles  Aerosols  Meteorological impact  Parameterizations  Eastern China