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The ruminal microbiome associated with methane emissions from ruminant livestock

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Journal of Animal Science and Biotechnology 2017年第2期8卷 289-299页

作者： Ilma Tapio Timothy J.Snelling Francesco Strozzi R.john wallace Green Technology Natural Resources Institute FinlandJokioinenFinland Rowett Institute of Nutrition and Health University of AberdeenForesterhillAberdeen AB16 5BDUK. PTP Via Einstein-Loc.Cascina Codazza26900 Lodiltaly

Methane emissions from ruminant livestock contribute significantly to the large environmental footprint of *** rumen is the principal source of methane, and certain features of the microbiome are associated with low/high methane phenotypes. Despite their primary role in methanogenesis, the abundance of archaea has only a weak correlation with methane emissions from individual animals. The composition of the archaeal community appears to have a stronger effect, with animals harbouring the Methanobrevibacter gottschalki clade tending to be associated with greater methane emissions. Ciliate protozoa produce abundant H_2, the main substrate for methanogenesis in the rumen,and their removal（defaunation） results in an average 11% lower methane emissions in vivo, but the results are not consistent. Different protozoal genera seem to result in greater methane emissions, though community types（A, AB, B and O） did not differ. Within the bacteria, three different ‘ruminotypes＇ have been identified, two of which predispose animals to have lower methane emissions. The two low-methane ruminotypes are generally characterized by less abundant H_2-producing bacteria. A lower abundance of Proteobacteria and differences in certain Bacteroidetes and anaerobic fungi seem to be associated with high methane emissions. Rumen anaerobic fungi produce abundant H_2 and formate, and their abundance generally corresponds to the level of methane emissions. Thus, microbiome analysis is consistent with known pathways for H_2 production and methanogenesis, but not yet in a predictive manner. The production and utilisation of formate by the ruminal microbiota is poorly understood and may be a source of variability between animals.

关键词： Archaea Methane Microbiome Rumen

ZONAL AND MERIDIONAL CIRCULATIONS IN THE EQUA-TORIALZONE AS DEDUCED FROM THE DIVERGENCE FIELD OF THE SURFACE WIND

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Advances in Atmospheric Sciences 1987年第4期4卷 432-446页

作者：王绍武,Todd P.Mitchell,john M.wallace Department of Geophysics Peking University Todd P. Mitchell and john M. wallace Department of Atmospheric Sciences University of Washington U.S.A. Department of Atmospheric Sciences University of Washington U.S.A. Department of Atmospheric Sciences University of Washington U.S.A.

The zonal and meridional circulations and their variability arc examined on the basis of the surface wind data for 1950-1979. The climatological mean zonal wind and its divergence arc examined in reference to the Walker Circulation. The role played by the meridional circulation in contributing to convergence of the surface wind field within the equatorial zone is emphasized. Regression coefficients are used to infer seasonal mean anomalies of divergence of the surface wind in years when the sea level pressure is 1 hPa above normal at Darwin, a condition representative of El Nino events. It is shown that anomalies in the divergence associated with the meridional wind component are primarily responsible for the heavy precipitation in the Central Pacific, while the anomalous divergence associated with the zonal wind component may cause the drought in the Western Pacific near Indonesia. A similar pattern of divergence anomalies is evident during three consecutive seasons beginning in northern summer and end

关键词： Nino over ZONAL AND MERIDIONAL CIRCULATIONS IN THE EQUA-TORIALZONE AS DEDUCED FROM THE DIVERGENCE FIELD OF THE SURFACE WIND

Chrysanthemum coronarium as a Modulator of the Biohydrogenation of Linoleic Acid in the Rumen

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Chrysanthemum coronarium as a Modulator of the Biohydrogenat...

Adaptive and local analysis of climate data

中国畜牧兽医学会家畜内科学分会2009年学术研讨会

作者： john wallace Rowett Research Institute University of AberdeenAberdeen AB21 9SBUK

Inclusion of a daisy plant,Chrysanthemum coronarium,in a dairy sheep diet has been reported to result in increased concentrations of health-promoting conjugated linoleic acids(CLA) and vaccenic acid(VA;trans-11-18:1) in *** aim of this study was to determine if *** affected the biohydrogenation of linoleic acid(LA;cis-9,cis-12-18:2) to CLA,VA and stearic acid(SA;18:0) by ruminal *** digesta from four sheep receiving a mixed hay-concentrate diet were incubated in vitro with LA±dried whole-plant *** *** *** of LA disappearance and SA production decreased(P<0.05) as a result of *** addition,and VA accumulation doubled(P<0.05).Chrysanthemum parthenium and Chrysanthemum vulgare had much smaller effects on biohydrogenation,and commercial samples of *** flowers and leaves were also less effective than *** *** *** added to cultures of the only known ruminal SA-forming bacterium,Clostridium proteoclasticum,also inhibited LA metabolism by,but not growth of,this *** analysis indicated that *** *** Gem had a high content ofα-linolenic acid(LNA;cis-9,cis-12,cis-15-18:3;1.76%) compared to the other samples(<0.2%). In fractions derived from differential(Soxhlet) solvent extraction,only extracts containing LNA affected LA metabolism by *** LNA inhibits biohydrogenation of LA at high concentrations, it was concluded that LNA was responsible for changes in the biohydrogenating activity of ruminal bacteria that had lead to the altered fatty acid composition of milk from animals receiving ***.

关键词： biohydrogenation conjugated linoleic acid rumen vaccenic acid

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Engineering Sciences 2014年第2期12卷 36-40页

作者： Wu Zhaohua Huang Norden E wallace john M Department of Earth Ocean and Atmospheric ScienceFlorida State University First Institute of Oceanography SOA Department of Atmospheric Sciences University of Washington

This paper focuses on how to extract physically meaningful information from climate data,with emphases placed on adaptive and local analysis. It is argued that many traditional statistical analysis methods with rigorous mathematical footing may not be efficient in extracting essential physical information from climate data;rather,adaptive and local analysis methods that agree well with fundamental physical principles are more capable of capturing key information of climate data. To illustrate the improved power of adaptive and local analysis of climate data,we also introduce briefly the empirical mode decomposition and its later developments.

关键词： statistical analysis of data adaptive analysis of data locality of analysis empirical mode decom- position ensemble empirical mode decomposition global warming trend multidecadal climate variability

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瘤胃被保护脂肪在奶牛日粮中的应用

国外畜牧学（饲料） 1997年第3期 28-30页

作者：苏从成王荣芝 john wallace

使高产奶牛摄取更多的能量是一种挑战,特别是在泌乳早期和炎热天气。补充过瘤胃脂肪或被保护脂肪是最有效的饲养手段之一。这种方法从开始试验已有20多年,商业上实际应用也有15年以上。但至今,并不是所有的被保护脂肪产品都以相同的方... 详细信息

使高产奶牛摄取更多的能量是一种挑战,特别是在泌乳早期和炎热天气。补充过瘤胃脂肪或被保护脂肪是最有效的饲养手段之一。这种方法从开始试验已有20多年,商业上实际应用也有15年以上。但至今,并不是所有的被保护脂肪产品都以相同的方式进行作用,或在家畜中导致相似的生产性能。而且,这些产品在配合饲料时的需要量不同,操作特性也不同。泌乳早期的能量挑战在泌乳最初的2～3个月内。

关键词：瘤胃脂肪乳牛饲料饲养

Government and Business Shall Increase Communications

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China's Foreign Trade 2016年第5期 16-页

作者： john wallace Hope Denton Corrs Chambers Westgarth

The global government and business industry shall enhance *** raised the'Belt and Road'initiative,which further promoted the economic integration of European and Asian *** is a good trend for Europe,Asia and the whole... 详细信息

关键词： more will Government and Business Shall Increase Communications

从全球地表平均温度时间序列中识别自然气候变率信号

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沙漠与绿洲气象 2010年第5期4卷 61-62页

作者： David W J Thompson john M wallace Phil D Jones john J Kenndhy 尹仔锋

全球表面平均温度受到自然变率和人为强迫两方面影响。本文研究有关1900年1月—2009年3月全球平均温度时间序列即自然气候变率中的信号鉴别和剔除问题,研发了一系列简单的、基于物理学的方法,并将其应用于区分厄尔尼诺—南方涛动（ENSO... 详细信息

全球表面平均温度受到自然变率和人为强迫两方面影响。本文研究有关1900年1月—2009年3月全球平均温度时间序列即自然气候变率中的信号鉴别和剔除问题,研发了一系列简单的、基于物理学的方法,并将其应用于区分厄尔尼诺—南方涛动（ENSO）,高纬度大陆冬季海洋气团平流变化和由火山爆发导致的大量气溶胶进入平流层这三种自然现象对气候的影响。在ENSO和高纬度温度平流的作用从全球平均温度的记录中剔除之后,显示于仪表的火山爆发及其变化的信号变得更加显而易见。随后火山爆发的影响就从记录中过滤掉,而剩下的时间序列则显示出自1950年以来全球气温几乎是一个单调的递增模式。结果还揭示,年际时间尺度海陆耦合的影响超过了ENSO和火山爆发。一般而言,全球陆地和海洋平均温度的情况紧密地同海洋气团主导陆地的那2~3个月相关。大西洋海面温度大振幅的扰动使这些耦合波动呈现为一个复杂的空间信号。

关键词：表面平均温度气候变率自然现象时间序列信号鉴别火山爆发识别地表

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大气科学

作者： (美)约翰·M. 华莱士(john M. wallace)，(美)彼得·V. 霍布斯(Peter V. Hobbs)

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ILED阵列:货真价实的柔性显示器

国防制造技术 2009年第5期 33-33页

作者： john wallace 李小磊

人们通常认为柔性显示器耐用性不佳。柔性显示器一般是采用有机发光二极管(0LED)技术,存在一个主要问题:如果显示器弯曲,发光像素也会弯曲;采用E-Ink电泳技术的非发光柔性显示器也存在需要柔性像素的问题。这不但限制了显示器的寿命和... 详细信息

人们通常认为柔性显示器耐用性不佳。柔性显示器一般是采用有机发光二极管(0LED)技术,存在一个主要问题:如果显示器弯曲,发光像素也会弯曲;采用E-Ink电泳技术的非发光柔性显示器也存在需要柔性像素的问题。这不但限制了显示器的寿命和发光材料的选取,而且还限制了大半径弯曲的"挠曲"。

关键词：柔性显示器 ILED阵列有机发光二极管发光材料耐用性源矩阵电泳技术砷化铝全彩色半导体