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15篇 您的检索式:作者名="J.Lewis"
    题名 作者 年代 出处 被引量
1The influence of land use change on the spatial–temporal variability of habitat quality between 1990 and 2010 in Northeast China显示文摘Land use changes are a direct consequence of interactions between humans and nature.Analysing the spatial and temporal changes in habitat quality brought about by land use change can provide a scientific basis for ecological protection and land planning.Based on the analysis of land use change from 1990 to 2010 in Northeast China,we used the InVEST(integrated valuation of ecosystem services and trade-offs)module to evaluate habitat quality based on watershed subdivision.The results show that:(1)the main land use changes from 1990 to 2010 were the transition from grasslands and forest lands to agricultural lands,which led to a decrease in connectivity of landscape and an increase in fragmentation;(2)areas of high habitat quality were distributed north of the Greater Khingan Mountains,the region of the Lesser Khingan Mountains and east of the Changbai Mountains,while the central plain had low habitat quality;(3)agricultural lands had the largest effect on habitat degradation among all habitat threats.During these 2 decades,the contribution of agricultural lands to habitat degradation were 43.4%in 1990,44.6%in 2000 and 43.9%in 2010;and,(4)at a landscape scale,patch density and splitting index present noticeable negative correlations with habitat quality index.Habitat quality was significantly affected by landscape fragmentation and decreased connectivity.Limin Dai Shanlin Li Bernard J.Lewis Jian Wu Dapao Yu Wangming Zhou Li Zhou Shengnan Wu 2019Journal of Forestry Research2019,30,6:18
2妊娠母猪的饲养管理要点显示文摘1饲养目标 妊娠期间饲养管理的目标是准备分娩和哺乳。妊娠前期的饲养目标是确保胚胎存活,使其分娩更多仔猪;妊娠中期(30~75d)的饲养目标是保证胎儿发育、增加母猪体储(小母猪生长达到体成熟,或补充上一哺乳期造成的体储降低);妊娠后期的饲养目标是保证胎儿继续快速发育、促进乳腺组织发育准备泌乳。武书庚 Austin J.Lewis 2008中国畜牧杂志2008,44,16:7
3猪营养中的微量元素--铁、锰、锌及其它显示文摘1铁(Fe) 猪生产中常见Fe缺乏。乳仔猪迅速生长,再加上猪奶中Fe含量较低,会使乳仔猪动用胎儿时储存在肝脏中的Fe,若此时不能及时得到补充,则容易导致Fe缺乏性贫血。武书庚 Austin J.Lewis 2008中国畜牧杂志2008,44,24:4
4新疆二种白蛉分类地位的校订显示文摘研究了存放在英国伦敦自然历史博物馆 (BMNH)的中国新疆和哈萨克斯坦、吉尔吉斯坦等地的有关白蛉标本 ,发现丁绍铎和何凯增 (196 2 )报道的“硕大白蛉”(P.major Annandale,1910 sensu Ting & Ho,196 2 )及杨赣源、熊光华(196 5 )的“硕大白蛉吴氏亚种”(P. major wui Yang & Xiong,196 5 )两者皆是斯氏白蛉 (P. smirnovi Perfiliew,194 1)的异名。丁、何的“微小白蛉新疆变种”(P.minutus var.sinkiangensis Ting & Ho,196 2 )应属于司蛉属 (Genus SergentomyiaFranca & Parrot,192 0 )司蛉亚属触角组 (antennata- group Theodor,195 8) ,兹重新命名为新疆司蛉 Sergentomyia(Sergen-tomyia) sinkiangensis (Ting & Ho,196 2 ) nom. nov.,并确定了选模。冷延家 Richard P.LANE Divid J.LEWIS 2002中国寄生虫病防治杂志2002,15,5:4
5Effects of management regimes on carbon sequestration under the Natural Forest Protection Program in northeast China显示文摘Carbon sinks constitute an important element within the complex phenomenon of global climate change,and forest ecosystems are important global carbon sinks.The Natural Forest Protection Program(NFPP) is an ecological program in China that was established after catastrophic flooding in the country in 1998.The goals of the NFPP are to curb the deterioration of the ecological environment,strengthen the protection and restoration of habitat to increase biodiversity,and rehabilitate natural forests to support sustainable development in forest regions.This study looked at changes in carbon sequestration in a forested area of northeast China after the inception of the NFPP.The program divides China's natural forests into three classes—commercial and two types of noneconomic forests—that are subject to management regimes prescribing varying levels of timber harvest,afforestation,and reforestation.During the 18-year period from 1998 to 2015,the total amount of carbon sequestration increased at an average annual rate of 0.04 MT C.This trend reflects a transformation of forest management practices after implementation of the NFPP that resulted in prohibited and/or restricted logging and tighter regulation of allowable harvest levels for specific areas.In documenting this trend,guidelines for more effective implementation of forestry programs such as the NFPP in other countries in the future are also suggested.Linhai Jiang Wei Zhao Bernard J.Lewis Yawei Wei Limin Dai 2018Journal of Forestry Research2018,29,5:3
6哺乳母猪的饲养管理要点显示文摘1饲养目标 母猪饲养的最终目标是延长其种用寿命,种猪中哺乳母猪最难饲喂。结合瘦肉品系的选育,调整饲养管理,最终改善健康状况和生产性能。在成功增加仔猪体重的同时,哺乳期(尤其是初产母猪)的采食能力仍是限制产奶量的关键因子。陈巨志 Austin J.Lewis 2008中国畜牧杂志2008,44,18:2
7猪营养中的微量元素显示文摘微量元素是机体需要但体内含量较少的营养素,它与常量元素的区别在于机体对其的需要量和储存量,铁正好处于分界点。过去25年里对微量元素和宏量元素代谢的研究,使人们认识到各元素的功能是相互交叉,且不能分开的。从本期开始,本栏目将对猪饲料中常用的几种微量元素的营养研究进展做以介绍。Austin J.Lewis 武书庚(译) 程宗佳(校) 2008中国畜牧杂志2008,44,20:2
8Nonsynonymous variants in the SMAD6 gene predispose to congenital cardiovascular malformation显示文摘Huay L.Tan EliseGlen AnaT?pf DarrochHall John JO’Sullivan LindaSneddon ChristopherWren PeterAvery Richard J.Lewis Peterten Dijke Helen M.Arthur Judith A.Goodship Bernard D.Keavney 2012Hum. Mutat2012,,:1
9The strength and stiffness of perimysial connective tissue isolated from cooked beef muscle显示文摘Graham J.Lewis Peter P.Purslow 0,,04:1
10Successive annual applications of organic manures for cut grass: short‐term observations on utilization of manure nitrogen显示文摘C. P.Beckwith P. J.Lewis A. G.Chalmers M. A.Froment K. A.Smith 2002Grass and Forage Science2002,,3:1
11Cloning and characterisation of a prenyltransferase from the aphid Myzus persicae with potential involvement in alarm pheromone biosynthesis显示文摘M. J.Lewis I. M.Prosser A.Mohib L. M.Field 2008Insect Molecular Biology2008,,4:1
12Successive annual applications of organic manures for cut grass: short‐term observations on utilization of manure nitrogen显示文摘C. P.Beckwith P. J.Lewis A. G.Chalmers M. A.Froment K. A.Smith 2002Grass and Forage Science2002,,3:1
13Segmentation by domestic visitor motivation: Changbai Mountain Biosphere Reserve, China显示文摘Protected areas have become important tourism products that promoted as attractions by the tourism industry. Taking the Changbai Mountain Biosphere Reserve in Northeast China as a case, this study addresses visitor needs as a basis for developing a tourism strategy aimed at enhancing tourist opportunities at this reserve. A factor-cluster approach was employed to identify visitor segment profiles based on their visit motivations. Through random sampling, a pencil-and-paper questionnaire in Chinese language was collected from 637 domestic tourists in the study area. A principal components analysis of motivations revealed eight motivational factors, and four distinct groups of tourists – Nature travelers, Cultural landscape tourists, Food & shopping enthusiasts, and Eclectic adventurers – were identified. Understanding the differences in these visitor segments will help the management authority effectively analyze nature reserve attributes and provide alternative activities and services to tourists. Finally, within the dual framework of market segmentation and destination management some management recommendations and marketing implications are suggested.GU Xiao-ping Bernard J.LEWIS NIU Li-jun YU Da-pao ZHOU Li ZHOU Wang-ming GONG Zhen-cai TAI Zhi-juan DAI Li-min 2018Journal of Mountain Science2018,15,8:1
14猪营养中的微量元素--硒显示文摘50年前人们就认识到了硒(se)是动物必需的微量元素(Schwarz和Foltz,1957),随后发现se能预防羊的白肌病(Muth等,1958;Oldfield等,1960)以及其它动物的肝脏坏疽、心肌病和渗出性素质病(NRC,1983)。但直到1973年才认识到Se是谷胱甘肽过氧化酶(GSH—Px)的组成成分,在体内发挥其生物学功能(Rotruck等,1973),进一步的研究表明,Se不仅影响动物的生产性能,还影响动物的健康。武书庚 程宗佳 Austin J.Lewis 2008中国畜牧杂志2008,44,22:0
15STUDIES ON SYNTHESIS, STRUCTURE AND REACTIVITY OF ACTIVATED Os_6 RAFT-LIKE CLUSTERS显示文摘In this paper we report the synthesis and activation of OS-6 raft-llke planar clusters. The activated OS-66 raft-like clusters [OS-66(CO)20(MeCN)] and [OS-66(CO)19 (MeCN)2] have been prepared by involving PdCl2 as catalyst. Trimethylamine oxide (Me3NO) has been used as an activation reagent to oxidize several carbonyl ligands coordinated in the activated clusters and to get a series of activated OS-66 raft-like clusters [OS-66(CO)21-x(MeCN)x] (n = 1--5) and corresponding substituted clusters [OS-66(CO)21-x(P(OMe)3)x] (n=1--5). The structures of these OS-66 raft-like clusters have been characterized by the infrared spectra (IR), nuclear magnetic resonance spectra (NMR) and mass spectra (MS), and the characters of the raft-like planar structure and reactivity above have also been discussed in this paper.刘家础 B.F.G.JOHNSON J.LEWIS 1990Science China Chemistry1990,33,4:0
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