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Analysis of compositions of microbiomes with bias correction 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Lin, Huang;  Das Peddada, Shyamal
收藏  |  浏览/下载:2/0  |  提交时间:2020/07/21
Ambient weathering of magnesium oxide for CO2 removal from air 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  McQueen, Noah;  Kelemen, Peter;  Dipple, Greg;  Renforth, Phil;  Wilcox, Jennifer
收藏  |  浏览/下载:8/0  |  提交时间:2020/07/06
Assessing the effectiveness of a national protected area network for carnivore conservation 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Terraube, J.;  Van Doninck, J.;  Helle, P.;  Cabeza, M.
收藏  |  浏览/下载:1/0  |  提交时间:2020/06/16
Four-dimensional surface motions of the Slumgullion landslide and quantification of hydrometeorological forcing 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Hu, Xie;  Buergmann, Roland;  Schulz, William H.;  Fielding, Eric J.
收藏  |  浏览/下载:6/0  |  提交时间:2020/06/09
Nearest neighbours reveal fast and slow components of motor learning 期刊论文
NATURE, 2020, 577 (7791) : 526-+
作者:  Kollmorgen, Sepp;  Hahnloser, Richard H. R.;  Mante, Valerio
收藏  |  浏览/下载:4/0  |  提交时间:2020/07/03

A new method for analysing change in high-dimensional data is based on nearest-neighbour statistics and is applied here to song dynamics during vocal learning in zebra finches, but could potentially be applied to other biological and artificial behaviours.


Changes in behaviour resulting from environmental influences, development and learning(1-5) are commonly quantified on the basis of a few hand-picked features(2-4,6,7) (for example, the average pitch of acoustic vocalizations(3)), assuming discrete classes of behaviours (such as distinct vocal syllables)(2,3,8-10). However, such methods generalize poorly across different behaviours and model systems and may miss important components of change. Here we present a more-general account of behavioural change that is based on nearest-neighbour statistics(11-13), and apply it to song development in a songbird, the zebra finch(3). First, we introduce the concept of '  repertoire dating'  , whereby each rendition of a behaviour (for example, each vocalization) is assigned a repertoire time, reflecting when similar renditions were typical in the behavioural repertoire. Repertoire time isolates the components of vocal variability that are congruent with long-term changes due to vocal learning and development, and stratifies the behavioural repertoire into '  regressions'  , '  anticipations'  and '  typical renditions'  . Second, we obtain a holistic, yet low-dimensional, description of vocal change in terms of a stratified '  behavioural trajectory'  , revealing numerous previously unrecognized components of behavioural change on fast and slow timescales, as well as distinct patterns of overnight consolidation(1,2,4,14,15) across the behavioral repertoire. We find that diurnal changes in regressions undergo only weak consolidation, whereas anticipations and typical renditions consolidate fully. Because of its generality, our nonparametric description of how behaviour evolves relative to itself-rather than to a potentially arbitrary, experimenter-defined goal(2,3,14,16)-appears well suited for comparing learning and change across behaviours and species(17,18), as well as biological and artificial systems(5).


  
Partial cross mapping eliminates indirect causal influences 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Leng, Siyang;  Ma, Huanfei;  Kurths, Juergen;  Lai, Ying-Cheng;  Lin, Wei;  Aihara, Kazuyuki;  Chen, Luonan
收藏  |  浏览/下载:11/0  |  提交时间:2020/06/01
Protein-structure prediction gets real 期刊论文
NATURE, 2020, 577 (7792) : 627-628
作者:  Pillai, Arvind S.;  Chandler, Shane A.;  Liu, Yang;  Signor, Anthony, V;  Cortez-Romero, Carlos R.;  Benesch, Justin L. P.;  Laganowsky, Arthur;  Storz, Jay F.;  Hochberg, Georg K. A.;  Thornton, Joseph W.
收藏  |  浏览/下载:11/0  |  提交时间:2020/07/03

Two threads of research in the quest for methods that predict the 3D structures of proteins from their amino-acid sequences have become fully intertwined. The result is a leap forward in the accuracy of predictions.


  
DNA metabarcoding reveals metacommunity dynamics in a threatened boreal wetland wilderness 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (15) : 8539-8545
作者:  Bush, Alex;  Monk, Wendy A.;  Compson, Zacchaeus G.;  Peters, Daniel L.;  Porter, Teresita M.;  Shokralla, Shadi;  Wright, Michael T. G.;  Hajibabaei, Mehrdad;  Baird, Donald J.
收藏  |  浏览/下载:16/0  |  提交时间:2020/05/13
occupancy  detectability  taxonomic resolution  stochasticity  power analysis  
Preparation of cyclohexene isotopologues and stereoisotopomers from benzene 期刊论文
NATURE, 2020, 581 (7808) : 288-+
作者:  Shimazaki, Yuya;  Schwartz, Ido;  Watanabe, Kenji;  Taniguchi, Takashi;  Kroner, Martin;  Imamoglu, Atac
收藏  |  浏览/下载:12/0  |  提交时间:2020/07/03

The hydrogen isotopes deuterium (D) and tritium (T) have become essential tools in chemistry, biology and medicine(1). Beyond their widespread use in spectroscopy, mass spectrometry and mechanistic and pharmacokinetic studies, there has been considerable interest in incorporating deuterium into drug molecules(1). Deutetrabenazine, a deuterated drug that is promising for the treatment of Huntington'  s disease(2), was recently approved by the United States'  Food and Drug Administration. The deuterium kinetic isotope effect, which compares the rate of a chemical reaction for a compound with that for its deuterated counterpart, can be substantial(1,3,4). The strategic replacement of hydrogen with deuterium can affect both the rate of metabolism and the distribution of metabolites for a compound(5), improving the efficacy and safety of a drug. The pharmacokinetics of a deuterated compound depends on the location(s) of deuterium. Although methods are available for deuterium incorporation at both early and late stages of the synthesis of a drug(6,7), these processes are often unselective and the stereoisotopic purity can be difficult to measure(7,8). Here we describe the preparation of stereoselectively deuterated building blocks for pharmaceutical research. As a proof of concept, we demonstrate a four-step conversion of benzene to cyclohexene with varying degrees of deuterium incorporation, via binding to a tungsten complex. Using different combinations of deuterated and proteated acid and hydride reagents, the deuterated positions on the cyclohexene ring can be controlled precisely. In total, 52 unique stereoisotopomers of cyclohexene are available, in the form of ten different isotopologues. This concept can be extended to prepare discrete stereoisotopomers of functionalized cyclohexenes. Such systematic methods for the preparation of pharmacologically active compounds as discrete stereoisotopomers could improve the pharmacological and toxicological properties of drugs and provide mechanistic information related to their distribution and metabolism in the body.


Cyclohexene isotopologues and stereoisotopomers with varying degrees of deuteration are formed by binding a tungsten complex to benzene, which facilitates the selective incorporation of deuterium into any position on the ring.


  
Accurate compound-specific C-14 dating of archaeological pottery vessels 期刊论文
NATURE, 2020, 580 (7804) : 506-+
作者:  Yin, Yafei;  Lu, J. Yuyang;  Zhang, Xuechun;  Shao, Wen;  Xu, Yanhui;  Li, Pan;  Hong, Yantao;  Cui, Li;  Shan, Ge;  Tian, Bin;  Zhang, Qiangfeng Cliff;  Shen, Xiaohua
收藏  |  浏览/下载:20/0  |  提交时间:2020/05/13

Pottery is one of the most commonly recovered artefacts from archaeological sites. Despite more than a century of relative dating based on typology and seriation(1), accurate dating of pottery using the radiocarbon dating method has proven extremely challenging owing to the limited survival of organic temper and unreliability of visible residues(2-4). Here we report a method to directly date archaeological pottery based on accelerator mass spectrometry analysis of C-14 in absorbed food residues using palmitic (C-16:0) and stearic (C-18:0) fatty acids purified by preparative gas chromatography(5-8). We present accurate compound-specific radiocarbon determinations of lipids extracted from pottery vessels, which were rigorously evaluated by comparison with dendrochronological dates(9,10) and inclusion in site and regional chronologies that contained previously determined radiocarbon dates on other materials(11-15). Notably, the compound-specific dates from each of the C-16:0 and C-18:0 fatty acids in pottery vessels provide an internal quality control of the results(6) and are entirely compatible with dates for other commonly dated materials. Accurate radiocarbon dating of pottery vessels can reveal: (1) the period of use of pottery  (2) the antiquity of organic residues, including when specific foodstuffs were exploited  (3) the chronology of sites in the absence of traditionally datable materials  and (4) direct verification of pottery typochronologies. Here we used the method to date the exploitation of dairy and carcass products in Neolithic vessels from Britain, Anatolia, central and western Europe, and Saharan Africa.


Using lipid residues absorbed in potsherds, the ages of pottery from various archaeological sites are determined and validated using sites for which the dates are well known from other methods.