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81.
S Neph J Vierstra AB Stergachis AP Reynolds E Haugen B Vernot RE Thurman S John R Sandstrom AK Johnson MT Maurano R Humbert E Rynes H Wang S Vong K Lee D Bates M Diegel V Roach D Dunn J Neri A Schafer RS Hansen T Kutyavin E Giste M Weaver T Canfield P Sabo M Zhang G Balasundaram R Byron MJ MacCoss JM Akey MA Bender M Groudine R Kaul JA Stamatoyannopoulos 《Nature》2012,489(7414):83-90
82.
International debate on the merits of vaccinating poultry against the H5N1 influenza A virus has raised concerns about the possibility of an increased risk of between-flock transmission before outbreaks are detected. Here we show that this 'silent spread' can occur because of incomplete protection at the flock level, even if a vaccine is effective in individual birds. The use of unvaccinated sentinels can mitigate, although not completely eliminate, the problem. 相似文献
83.
Samples of material returned from the Moon have established that widespread lunar volcanism ceased about 3.2 Gyr ago. Crater statistics and degradation models indicate that last-gasp eruptions of thin basalt flows continued until less than 1.0 Gyr ago, but the Moon is now considered to be unaffected by internal processes today, other than weak tidally driven moonquakes and young fault systems. It is therefore widely assumed that only impact craters have reshaped the lunar landscape over the past billion years. Here we report that patches of the lunar regolith in the Ina structure were recently removed. The preservation state of relief, the number of superimposed small craters, and the 'freshness' (spectral maturity) of the regolith together indicate that features within this structure must be as young as 10 Myr, and perhaps are still forming today. We propose that these features result from recent, episodic out-gassing from deep within the Moon. Such out-gassing probably contributed to the radiogenic gases detected during past lunar missions. Future monitoring (including Earth-based observations) should reveal the composition of the gas, yielding important clues to volatiles archived at great depth over the past 4-4.5 Gyr. 相似文献
84.
During meiosis, accurate separation of maternal and paternal chromosomes requires that they first be connected to one another through homologous recombination. Meiotic recombination has many intriguing but poorly understood features that distinguish it from recombination in mitotically dividing cells, and several of these features depend on the meiosis-specific DNA strand exchange protein Dmc1 (disrupted meiotic cDNA1). Many questions about this protein have arisen since its discovery more than a decade ago, but recent genetic and biochemical breakthroughs promise to shed light on the unique behaviours and functions of this central player in the remarkable chromosome dynamics of meiosis. 相似文献
85.
Matthew L. Buffington Massimo Giorgini Chia-Hua Lue Giorgio Formisano Pasquale Cascone Mattias Forshage 《Journal of Natural History》2020,54(9-12):565-583
ABSTRACT In the search for native Asian parasitoids of Drosophila suzukii, the notorious spotted-wing Drosophila (SWD), an odd new species of Eucoilinae was discovered. Leptopilina lasallei sp. nov. is herein described and diagnosed relative to other eucoilines associated with drosophilid hosts. Morphologically, L. lasallei is somewhat aberrant within Leptopilina; phylogenetically, L. lasallei is sister group to the core Leptopilina. In the process of investigating L. lasallei, a de novo molecular phylogeny of Leptopilina was generated and is included here. The integrated approach used for the characterisation of L. lasallei, and the resulting phylogeny of Leptopilina, produced data useful to select parasitoid species for SWD biological control.http://www.zoobank.org/urn:lsid:zoobank.org:act:402D504A-4616-4524-85D7-1C13A6276F06 http://www.zoobank.org/urn:lsid:zoobank.org:act:402D504A-4616-4524-85D7-1C13A6276F06 相似文献
86.
87.
iASPP oncoprotein is a key inhibitor of p53 conserved from worm to human 总被引:39,自引:0,他引:39
Bergamaschi D Samuels Y O'Neil NJ Trigiante G Crook T Hsieh JK O'Connor DJ Zhong S Campargue I Tomlinson ML Kuwabara PE Lu X 《Nature genetics》2003,33(2):162-167
We have previously shown that ASPP1 and ASPP2 are specific activators of p53; one mechanism by which wild-type p53 is tolerated in human breast carcinomas is through loss of ASPP activity. We have further shown that 53BP2, which corresponds to a C-terminal fragment of ASPP2, acts as a dominant negative inhibitor of p53 (ref. 1). Hence, an inhibitory form of ASPP resembling 53BP2 could allow cells to bypass the tumor-suppressor functions of p53 and the ASPP proteins. Here, we characterize such a protein, iASPP (inhibitory member of the ASPP family), encoded by PPP1R13L in humans and ape-1 in Caenorhabditis elegans. iASPP is an evolutionarily conserved inhibitor of p53; inhibition of iASPP by RNA-mediated interference or antisense RNA in C. elegans or human cells, respectively, induces p53-dependent apoptosis. Moreover, iASPP is an oncoprotein that cooperates with Ras, E1A and E7, but not mutant p53, to transform cells in vitro. Increased expression of iASPP also confers resistance to ultraviolet radiation and to cisplatin-induced apoptosis. iASPP expression is upregulated in human breast carcinomas expressing wild-type p53 and normal levels of ASPP. Inhibition of iASPP could provide an important new strategy for treating tumors expressing wild-type p53. 相似文献
88.
Molla R. Islam Yongfeng Gao Xue Li Qiang Matthew Zhang Menglian Wei Michael J. Serpe 《科学通报(英文版)》2014,59(32):4237-4255
Stimuli-responsive polymers have the extraor- dinary ability to change their physical and/or chemical state after they "detect" a change in their environment; their response depends dramatically on their chemical compo- sition. This property has been used for a plethora of applications; this review highlights their utility for human health. Specifically, this review will highlight efforts in the areas of sensing and biosensing, antimicrobial/antifouling coatings, tissue engineering and regenerative medicine, and drug delivery. Specific examples are given in each of these areas, with some focus on our work engineering poly(N- isopropylacrylamide)-based microgels and other respon- sive systems. 相似文献
89.
This paper investigates the feedback control of hidden Markov process(HMP) in the face of loss of some observation processes.The control action facilitates or impedes some particular transitions from an inferred current state in the attempt to maximize the probability that the HMP is driven to a desirable absorbing state.This control problem is motivated by the need for judicious resource allocation to win an air operation involving two opposing forces.The effectiveness of a receding horizon control scheme based on the inferred discrete state is examined.Tolerance to loss of sensors that help determine the state of the air operation is achieved through a decentralized scheme that estimates a continuous state from measurements of linear models with additive noise.The discrete state of the HMP is identified using three well-known detection schemes.The sub-optimal control policy based on the detected state is implemented on-line in a closed-loop,where the air operation is simulated as a stochastic process with SimEvents,and the measurement process is simulated for a range of single sensor loss rates. 相似文献
90.
原文载于《Discover》杂志2015年9月刊,摘选自马修·科布(Matthew Cobb)的著作《生命最大的秘密:角逐遗传密码真相的故事》(Life’s Greatest Secret:The Race to Crack the Genetic Code),该书于2015年7月由Basic Books出版。本文由张钫、史晓雷翻译。 相似文献