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Transparent ferroelectric crystals with ultrahigh piezoelectricity 期刊论文
NATURE, 2020, 577 (7790) : 350-+
作者:  Qiu, Chaorui;  Wang, Bo;  Zhang, Nan;  Zhang, Shujun;  Liu, Jinfeng;  Walker, David;  Wang, Yu;  Tian, Hao;  Shrout, Thomas R.;  Xu, Zhuo;  Chen, Long-Qing;  Li, Fei
收藏  |  浏览/下载:16/0  |  提交时间:2020/07/03

Transparent piezoelectrics are highly desirable for numerous hybrid ultrasound-optical devices ranging from photoacoustic imaging transducers to transparent actuators for haptic applications(1-7). However, it is challenging to achieve high piezoelectricity and perfect transparency simultaneously because most high-performance piezoelectrics are ferroelectrics that contain high-density light-scattering domain walls. Here, through a combination of phase-field simulations and experiments, we demonstrate a relatively simple method of using an alternating-current electric field to engineer the domain structures of originally opaque rhombohedral Pb(Mg1/3Nb2/3)O-3-PbTiO3 (PMN-PT) crystals to simultaneously generate near-perfect transparency, an ultrahigh piezoelectric coefficient d(33) (greater than 2,100 picocoulombs per newton), an excellent electromechanical coupling factor k(33) (about 94 per cent) and a large electro-optical coefficient gamma(33) (approximately 220 picometres per volt), which is far beyond the performance of the commonly used transparent ferroelectric crystal LiNbO3. We find that increasing the domain size leads to a higher d(33) value for the [001]-oriented rhombohedral PMN-PT crystals, challenging the conventional wisdom that decreasing the domain size always results in higher piezoelectricity(8-10). This work presents a paradigm for achieving high transparency and piezoelectricity by ferroelectric domain engineering, and we expect the transparent ferroelectric crystals reported here to provide a route to a wide range of hybrid device applications, such as medical imaging, self-energy-harvesting touch screens and invisible robotic devices.


  
Rapid growth of new atmospheric particles by nitric acid and ammonia condensation 期刊论文
NATURE, 2020, 581 (7807) : 184-+
作者:  Liang, Guanxiang;  Zhao, Chunyu;  Zhang, Huanjia;  Mattei, Lisa;  Sherrill-Mix, Scott;  Bittinger, Kyle;  Kessler, Lyanna R.;  Wu, Gary D.;  Baldassano, Robert N.;  DeRusso, Patricia;  Ford, Eileen;  Elovitz, Michal A.;  Kelly, Matthew S.;  Patel, Mohamed Z.;  Mazhani, Tiny;  Gerber, Jeffrey S.;  Kelly, Andrea;  Zemel, Babette S.;  Bushman, Frederic D.
收藏  |  浏览/下载:17/0  |  提交时间:2020/05/20

A list of authors and their affiliations appears at the end of the paper New-particle formation is a major contributor to urban smog(1,2), but how it occurs in cities is often puzzling(3). If the growth rates of urban particles are similar to those found in cleaner environments (1-10 nanometres per hour), then existing understanding suggests that new urban particles should be rapidly scavenged by the high concentration of pre-existing particles. Here we show, through experiments performed under atmospheric conditions in the CLOUD chamber at CERN, that below about +5 degrees Celsius, nitric acid and ammonia vapours can condense onto freshly nucleated particles as small as a few nanometres in diameter. Moreover, when it is cold enough (below -15 degrees Celsius), nitric acid and ammonia can nucleate directly through an acid-base stabilization mechanism to form ammonium nitrate particles. Given that these vapours are often one thousand times more abundant than sulfuric acid, the resulting particle growth rates can be extremely high, reaching well above 100 nanometres per hour. However, these high growth rates require the gas-particle ammonium nitrate system to be out of equilibrium in order to sustain gas-phase supersaturations. In view of the strong temperature dependence that we measure for the gas-phase supersaturations, we expect such transient conditions to occur in inhomogeneous urban settings, especially in wintertime, driven by vertical mixing and by strong local sources such as traffic. Even though rapid growth from nitric acid and ammonia condensation may last for only a few minutes, it is nonetheless fast enough to shepherd freshly nucleated particles through the smallest size range where they are most vulnerable to scavenging loss, thus greatly increasing their survival probability. We also expect nitric acid and ammonia nucleation and rapid growth to be important in the relatively clean and cold upper free troposphere, where ammonia can be convected from the continental boundary layer and nitric acid is abundant from electrical storms(4,5).


  
Senolytic CAR T cells reverse senescence-associated pathologies 期刊论文
NATURE, 2020, 583 (7814) : 127-+
作者:  Cortez, Jessica T.;  Montauti, Elena;  Shifrut, Eric;  Gatchalian, Jovylyn;  Zhang, Yusi;  Shaked, Oren;  Xu, Yuanming;  Roth, Theodore L.;  Simeonov, Dimitre R.;  Zhang, Yana;  Chen, Siqi;  Li, Zhongmei;  Woo, Jonathan M.;  Ho, Josephine;  Vogel, Ian A.
收藏  |  浏览/下载:66/0  |  提交时间:2020/07/03

Cellular senescence is characterized by stable cell-cycle arrest and a secretory program that modulates the tissue microenvironment(1,2). Physiologically, senescence serves as a tumour-suppressive mechanism that prevents the expansion of premalignant cells(3,4)and has a beneficial role in wound-healing responses(5,6). Pathologically, the aberrant accumulation of senescent cells generates an inflammatory milieu that leads to chronic tissue damage and contributes to diseases such as liver and lung fibrosis, atherosclerosis, diabetes and osteoarthritis(1,7). Accordingly, eliminating senescent cells from damaged tissues in mice ameliorates the symptoms of these pathologies and even promotes longevity(1,2,8-10). Here we test the therapeutic concept that chimeric antigen receptor (CAR) T cells that target senescent cells can be effective senolytic agents. We identify the urokinase-type plasminogen activator receptor (uPAR)(11)as a cell-surface protein that is broadly induced during senescence and show that uPAR-specific CAR T cells efficiently ablate senescent cells in vitro and in vivo. CAR T cells that target uPAR extend the survival of mice with lung adenocarcinoma that are treated with a senescence-inducing combination of drugs, and restore tissue homeostasis in mice in which liver fibrosis is induced chemically or by diet. These results establish the therapeutic potential of senolytic CAR T cells for senescence-associated diseases.


Chimeric antigen receptor (CAR) T cells targeting uPAR, a cell-surface protein that is upregulated on senescent cells, eliminate senescent cells in vitro and in vivo and reduce liver fibrosis in mice.


  
Molecular architecture of the human 17S U2 snRNP 期刊论文
NATURE, 2020, 583 (7815) : 310-+
作者:  Muench, David E.;  Olsson, Andre;  Ferchen, Kyle;  Pham, Giang;  Serafin, Rachel A.;  Chutipongtanate, Somchai;  Dwivedi, Pankaj;  Song, Baobao;  Hay, Stuart;  Chetal, Kashish;  Trump-Durbin, Lisa R.;  Mookerjee-Basu, Jayati;  Zhang, Kejian;  Yu, Jennifer C.
收藏  |  浏览/下载:18/0  |  提交时间:2020/07/03

The U2 small nuclear ribonucleoprotein (snRNP) has an essential role in the selection of the precursor mRNA branch-site adenosine, the nucleophile for the first step of splicing'  . Stable addition of U2 during early spliceosome formation requiresthe DEAD-box ATPase PRP5(2-7). Yeast U2 small nuclear RNA (snRNA) nucleotides that form base pairs with the branch site are initially sequestered in a branchpoint-interacting stem-loop (BSL)(8), but whether the human U2 snRNA folds in a similar manner is unknown. The U2 SF3B1 protein, a common mutational target in haematopoietic cancers(9), contains a HEAT domain (SF3B1(HEAT)) with an open conformation in isolated SF3b(10), but a closed conformation in spliceosomes(11), which is required for stable interaction between U2 and the branch site. Here we report a 3D cryo-electron microscopy structure ofthe human 17S U2 snRNP at a core resolution of 4.1 angstrom and combine it with protein crosslinking data to determine the molecular architecture of this snRNP. Our structure reveals that SF3B1(HEAT) interacts with PRP5 and TAT-SF1, and maintains its open conformation in U2 snRNP, and that U2 snRNA forms a BSL that is sandwiched between PRP5, TAT-SF1 and SF3B1(HEAT). Thus, substantial remodelling of the BSL and displacement of BSL-interacting proteins must occur to allow formation of the U2-branch-site helix. Our studies provide a structural explanation of why TAT-SF1 must be displaced before the stable addition of U2 to the spliceosome, and identify RNP rearrangements facilitated by PRP5 that are required for stable interaction between U2 and the branch site.


  
Origin of complexity in haemoglobin evolution 期刊论文
NATURE, 2020
作者:  Cheema, Suraj S.;  Kwon, Daewoong;  Shanker, Nirmaan;  dos Reis, Roberto;  Hsu, Shang-Lin;  Xiao, Jun;  Zhang, Haigang;  Wagner, Ryan;  Datar, Adhiraj;  McCarter, Margaret R.;  Serrao, Claudy R.;  Yadav, Ajay K.;  Karbasian, Golnaz;  Hsu, Cheng-Hsiang;  Tan, Ava J.;  Wang, Li-Chen;  Thakare, Vishal;  Zhang, Xiang;  Mehta, Apurva;  Karapetrova, Evguenia;  Chopdekar, Rajesh, V;  Shafer, Padraic;  Arenholz, Elke;  Hu, Chenming;  Proksch, Roger;  Ramesh, Ramamoorthy;  Ciston, Jim;  Salahuddin, Sayeef
收藏  |  浏览/下载:50/0  |  提交时间:2020/07/03

Most proteins associate into multimeric complexes with specific architectures(1,2), which often have functional properties such as cooperative ligand binding or allosteric regulation(3). No detailed knowledge is available about how any multimer and its functions arose during evolution. Here we use ancestral protein reconstruction and biophysical assays to elucidate the origins of vertebrate haemoglobin, a heterotetramer of paralogous alpha- and beta-subunits that mediates respiratory oxygen transport and exchange by cooperatively binding oxygen with moderate affinity. We show that modern haemoglobin evolved from an ancient monomer and characterize the historical '  missing link'  through which the modern tetramer evolved-a noncooperative homodimer with high oxygen affinity that existed before the gene duplication that generated distinct alpha- and beta-subunits. Reintroducing just two post-duplication historical substitutions into the ancestral protein is sufficient to cause strong tetramerization by creating favourable contacts with more ancient residues on the opposing subunit. These surface substitutions markedly reduce oxygen affinity and even confer cooperativity, because an ancient linkage between the oxygen binding site and the multimerization interface was already an intrinsic feature of the protein'  s structure. Our findings establish that evolution can produce new complex molecular structures and functions via simple genetic mechanisms that recruit existing biophysical features into higher-level architectures.


Experimental analysis of reconstructed ancestral globins reveals that haemoglobin'  s complex tetrameric structure and oxygen-binding functions evolved by simple genetic and biophysical mechanisms.


  
A conserved dendritic-cell regulatory program limits antitumour immunity 期刊论文
NATURE, 2020, 580 (7802) : 257-+
作者:  Perry, Rachel J.;  Zhang, Dongyan;  Guerra, Mateus T.;  Brill, Allison L.;  Goedeke, Leigh;  Nasiri, Ali R.;  Rabin-Court, Aviva;  Wang, Yongliang;  Peng, Liang;  Dufour, Sylvie;  Zhang, Ye;  Zhang, Xian-Man;  Butrico, Gina M.;  Toussaint, Keshia;  Nozaki, Yuichi;  Cline, Gary W.;  Petersen, Kitt Falk;  Nathanson, Michael H.;  Ehrlich, Barbara E.;  Shulman, Gerald I.
收藏  |  浏览/下载:27/0  |  提交时间:2020/07/03

After taking up tumour-associated antigens, dendritic cells in mouse and human tumours upregulate a regulatory gene program that limits dendritic cell immunostimulatory function, and modulating this program can rescue antitumor immunity in mice.


Checkpoint blockade therapies have improved cancer treatment, but such immunotherapy regimens fail in a large subset of patients. Conventional type 1 dendritic cells (DC1s) control the response to checkpoint blockade in preclinical models and are associated with better overall survival in patients with cancer, reflecting the specialized ability of these cells to prime the responses of CD8(+) T cells(1-3). Paradoxically, however, DC1s can be found in tumours that resist checkpoint blockade, suggesting that the functions of these cells may be altered in some lesions. Here, using single-cell RNA sequencing in human and mouse non-small-cell lung cancers, we identify a cluster of dendritic cells (DCs) that we name '  mature DCs enriched in immunoregulatory molecules'  (mregDCs), owing to their coexpression of immunoregulatory genes (Cd274, Pdcd1lg2 and Cd200) and maturation genes (Cd40, Ccr7 and Il12b). We find that the mregDC program is expressed by canonical DC1s and DC2s upon uptake of tumour antigens. We further find that upregulation of the programmed death ligand 1 protein-a key checkpoint molecule-in mregDCs is induced by the receptor tyrosine kinase AXL, while upregulation of interleukin (IL)-12 depends strictly on interferon-gamma and is controlled negatively by IL-4 signalling. Blocking IL-4 enhances IL-12 production by tumour-antigen-bearing mregDC1s, expands the pool of tumour-infiltrating effector T cells and reduces tumour burden. We have therefore uncovered a regulatory module associated with tumour-antigen uptake that reduces DC1 functionality in human and mouse cancers.


  
A genomic and epigenomic atlas of prostate cancer in Asian populations 期刊论文
NATURE, 2020: 93-+
作者:  Perry, Rachel J.;  Zhang, Dongyan;  Guerra, Mateus T.;  Brill, Allison L.;  Goedeke, Leigh;  Nasiri, Ali R.;  Rabin-Court, Aviva;  Wang, Yongliang;  Peng, Liang;  Dufour, Sylvie;  Zhang, Ye;  Zhang, Xian-Man;  Butrico, Gina M.;  Toussaint, Keshia;  Nozaki, Yuichi;  Cline, Gary W.;  Petersen, Kitt Falk;  Nathanson, Michael H.;  Ehrlich, Barbara E.;  Shulman, Gerald I.
收藏  |  浏览/下载:33/0  |  提交时间:2020/07/03

Prostate cancer is the second most common cancer in men worldwide(1). Over the past decade, large-scale integrative genomics efforts have enhanced our understanding of this disease by characterizing its genetic and epigenetic landscape in thousands of patients(2,3). However, most tumours profiled in these studies were obtained from patients from Western populations. Here we produced and analysed whole-genome, whole-transcriptome and DNA methylation data for 208 pairs of tumour tissue samples and matched healthy control tissue from Chinese patients with primary prostate cancer. Systematic comparison with published data from 2,554 prostate tumours revealed that the genomic alteration signatures in Chinese patients were markedly distinct from those of Western cohorts: specifically, 41% of tumours contained mutations in FOXA1 and 18% each had deletions in ZNF292 and CHD1. Alterations of the genome and epigenome were correlated and were predictive of disease phenotype and progression. Coding and noncoding mutations, as well as epimutations, converged on pathways that are important for prostate cancer, providing insights into this devastating disease. These discoveries underscore the importance of including population context in constructing comprehensive genomic maps for disease.


Genomic, transcriptomic and DNA methylation data from tissue samples from 208 Chinese patients with prostate cancer define the landscape of alterations in this population, and comparison with data from Western cohorts suggests that the disease may stratify into different molecular subtypes.


  
A lysosomal switch triggers proteostasis renewal in the immortal C. elegans germ lineage (vol 551, pg 629, 2017) 期刊论文
NATURE, 2020, 580 (7802) : E5-E5
作者:  Lu, Zhihao;  Zou, Jianling;  Li, Shuang;  Topper, Michael J.;  Tao, Yong;  Zhang, Hao;  Jiao, Xi;  Xie, Wenbing;  Kong, Xiangqian;  Vaz, Michelle;  Li, Huili;  Cai, Yi;  Xia, Limin;  Huang, Peng;  Rodgers, Kristen;  Lee, Beverly;  Riemer, Joanne B.;  Day, Chi-Ping;  Yen, Ray-Whay Chiu;  Cui, Ying;  Wang, Yujiao;  Wang, Yanni;  Zhang, Weiqiang;  Easwaran, Hariharan;  Hulbert, Alicia;  Kim, KiBem;  Juergens, Rosalyn A.;  Yang, Stephen C.;  Battafarano, Richard J.;  Bush, Errol L.;  Broderick, Stephen R.;  Cattaneo, Stephen M.;  Brahmer, Julie R.;  Rudin, Charles M.;  Wrangle, John;  Mei, Yuping;  Kim, Young J.;  Zhang, Bin;  Wang, Ken Kang-Hsin;  Forde, Patrick M.;  Margolick, Joseph B.;  Nelkin, Barry D.;  Zahnow, Cynthia A.;  Pardoll, Drew M.;  Housseau, Franck;  Baylin, Stephen B.;  Shen, Lin;  Brock, Malcolm V.
收藏  |  浏览/下载:26/0  |  提交时间:2020/07/03
Nightside condensation of iron in an ultrahot giant exoplanet 期刊论文
NATURE, 2020, 580 (7805) : 597-+
作者:  Lu, Zhihao;  Zou, Jianling;  Li, Shuang;  Topper, Michael J.;  Tao, Yong;  Zhang, Hao;  Jiao, Xi;  Xie, Wenbing;  Kong, Xiangqian;  Vaz, Michelle;  Li, Huili;  Cai, Yi;  Xia, Limin;  Huang, Peng;  Rodgers, Kristen;  Lee, Beverly;  Riemer, Joanne B.;  Day, Chi-Ping;  Yen, Ray-Whay Chiu;  Cui, Ying;  Wang, Yujiao;  Wang, Yanni;  Zhang, Weiqiang;  Easwaran, Hariharan;  Hulbert, Alicia;  Kim, KiBem;  Juergens, Rosalyn A.;  Yang, Stephen C.;  Battafarano, Richard J.;  Bush, Errol L.;  Broderick, Stephen R.;  Cattaneo, Stephen M.;  Brahmer, Julie R.;  Rudin, Charles M.;  Wrangle, John;  Mei, Yuping;  Kim, Young J.;  Zhang, Bin;  Wang, Ken Kang-Hsin;  Forde, Patrick M.;  Margolick, Joseph B.;  Nelkin, Barry D.;  Zahnow, Cynthia A.;  Pardoll, Drew M.;  Housseau, Franck;  Baylin, Stephen B.;  Shen, Lin;  Brock, Malcolm V.
收藏  |  浏览/下载:57/0  |  提交时间:2020/07/03

Ultrahot giant exoplanets receive thousands of times Earth'  s insolation(1,2). Their high-temperature atmospheres (greater than 2,000 kelvin) are ideal laboratories for studying extreme planetary climates and chemistry(3-5). Daysides are predicted to be cloud-free, dominated by atomic species(6) and much hotter than nightsides(5,7,8). Atoms are expected to recombine into molecules over the nightside(9), resulting in different day and night chemistries. Although metallic elements and a large temperature contrast have been observed(10-14), no chemical gradient has been measured across the surface of such an exoplanet. Different atmospheric chemistry between the day-to-night ('  evening'  ) and night-to-day ('  morning'  ) terminators could, however, be revealed as an asymmetric absorption signature during transit(4,7,15). Here we report the detection of an asymmetric atmospheric signature in the ultrahot exoplanet WASP-76b. We spectrally and temporally resolve this signature using a combination of high-dispersion spectroscopy with a large photon-collecting area. The absorption signal, attributed to neutral iron, is blueshifted by -11 +/- 0.7 kilometres per second on the trailing limb, which can be explained by a combination of planetary rotation and wind blowing from the hot dayside(16). In contrast, no signal arises from the nightside close to the morning terminator, showing that atomic iron is not absorbing starlight there. We conclude that iron must therefore condense during its journey across the nightside.


Absorption lines of iron in the dayside atmosphere of an ultrahot giant exoplanet disappear after travelling across the nightside, showing that the iron has condensed during its travel.


  
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:71/0  |  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.