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Ecological role of the giant root-rat(Tachyoryctes macrocephalus)in the Afroalpine ecosystem

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Integrative Zoology 2017年第4期12卷 333-344页

作者： j.nŠKlÍBA Tereza VlASATÁ Matěj.l.vy Ema HROUZKOVÁ Yonas MEHERETU Claudio SIllERO-ZUBIRI RadimŠUMBERA Faculty of Science University of South BohemiaCzech Republic Institute of Entomology Biology Centre CASCzech Republic Department of Biology College of Natural and Cmputational SciencesMekelle UniversityEthiopia Wildlife Conservation Research Unit Zoology DepartmentUniversity of OxfordUK

Rodents with prevailing subterranean activity usually play an important role in the ecosystems of which they are a part due to the combined effect of herbivory and soil *** is the case for the giant root-rat Tachyoryctes macrocephalus endemic to the Afroalpine ecosystem of the Bale Mountains,*** studied the impact of root-rats on various ecosystem features within a 3.5-ha study locality dominated by Alchemilla pasture,which represents an optimal habitat for this species,in 2 periods of a *** root-rats altered plant species composition,reducing the dominant forb,Alchemilla abyssinica,while enhancing Salvia merj.me and a few other species,and reduced vegetation cover,but not the fresh plant *** burrows were abandoned by root-rats,other rodents took them over and *** increased ***-rat burrowing created small-scale heterogeneity in soil compactness due to the backfilling of some unused burrow *** compacted soil tended to be rich in nutrients,including carbon,nitrogen and phosphorus,which likely affected the plant growth on sites where the vegetation has been reduced as a result of root-rat foraging and burrowing.

关键词： Afroalpine ecosystem engineer fossorial rodent soil disturbance Tachyoryctes macrocephalus

14-羟基-去乙基Vincadifformine的仿生合成及重排

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上海医科大学学报 1991年第2期18卷 123-128页

作者：闻韧 laronze j. Y. l.vy j. 上海医科大学药学院合成药物化学教研室法国Reims大学药学院天然物质研究所

六氢氮杂革并[4,5-b]吲哚甲酸甲酯(8)和2-羟基-5-碘甲基-四氢呋喃(10),经Kuehne仿生反应生成14α-和14β-羟基-去乙基vincadifformine(5a和5b)。5b经脱水生成去乙基tabersonine(4)。5a在过氧酸、三苯膦、醋酸作用下可仿生氧化-重排成14... 详细信息

六氢氮杂革并[4,5-b]吲哚甲酸甲酯(8)和2-羟基-5-碘甲基-四氢呋喃(10),经Kuehne仿生反应生成14α-和14β-羟基-去乙基vincadifformine(5a和5b)。5b经脱水生成去乙基tabersonine(4)。5a在过氧酸、三苯膦、醋酸作用下可仿生氧化-重排成14α-羟基-去乙基长春胺(6a)及其16-差向异物构体(6b)(83％:17％)。

关键词：仿生合成生物碱长春胺衍生物

1,10-二甲基-二氢利血平及其二氢异利血平的立体选择性合成

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有机化学 1991年第1期11卷 29-35页

作者：闻韧 j.-Y.laronze j.l.vy 上海医科大学药学院上海200032 法国Reims大学药学院 reims51096

育亨宾类(Yohimbimes)和杂育亨宾类(Heteroyohimbines)如利血平(Reserpine,1)、阿吗新(Aj.alicine)等是具有重要心脑血管活性的天然吲哚生物碱。1980年 Roycr 和l.vy 在研究吲哚生物碱合成中偶然发现3α-杂育亨宾生物碱四叶萝芙灵(Tetr... 详细信息

育亨宾类(Yohimbimes)和杂育亨宾类(Heteroyohimbines)如利血平(Reserpine,1)、阿吗新(Aj.alicine)等是具有重要心脑血管活性的天然吲哚生物碱。1980年 Roycr 和l.vy 在研究吲哚生物碱合成中偶然发现3α-杂育亨宾生物碱四叶萝芙灵(Tetraphylline,2)在先用氰基硼氢化钠和三氟醋酸,后用40%甲醛和氰基硼氢化钠处埋后,可直接一步得到2β,3α,7β-cis(B/C)-trans(C/D)的1,10-二甲基-2,7-二氢四叶萝芙灵(3a)。以后。

关键词：立体选择合成利血平异利血平

Adult bobcat(lynx rufus)habitat selection in a longleaf pine savanna

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Ecological Processes 2018年第1期7卷 206-217页

作者： Andrew R.little l.Mike Conner Michael j.Chamberlain Nathan P.Nibbelink Robert j.warren Warnell School of Forestry and Natural Resources University of Georgia180 E.Green StAthensGA 30602USA j.seph W.j.nes Ecological Research Center at Ichauway NewtonGeorgia 39870USA

Background:Pine savannas are primarily managed with frequent prescribed fire(≤3 years)to promote diversity of flora and fauna,and to maintain open,park-like conditions needed by species such as the endangered red-cockaded woodpecker(Picoides borealis).However,a knowledge gap exists in our understanding of bobcat(lynx rufus)habitat selection in longleaf pine savannas and research is warranted to direct our future management ***:We examined bobcat habitat selection in a pine savanna managed with frequent fires at two spatial scales(i.e.,study area boundary[hereafter,landscape scale])and annual area of use[95%kernel density;local scale],and assessed effects of prescribed fire on bobcat habitat ***,we monitored 45 bobcats(16 males and 29 females)during 2001–***:We found differential habitat selection by *** the landscape scale,female bobcats were closer to mixed pine-hardwoods,young pine,and secondary roads,but farther from mature pine and hardwoods stands relative to *** found no difference in selection of agriculture,shrub-scrub,and primary roads between *** the annual area of use scale,female bobcats were closer to secondary roads,but farther from agriculture and shrub-scrub relative to *** found no difference in selection of mature pine,mixed pine-hardwoods,hardwoods,young pine,and primary roads between *** primarily selected for stands burned≤1.1 years ***:Our results show that bobcats exploit a broad range of habitat types in pine landscapes managed with frequent fire and commonly use recently burned stands(≤1.1 year post-fire),suggesting prey in many areas of this system are at risk of bobcat ***,we suggest land managers consider scale of selection by bobcats when developing habitat management strategies.

关键词： Georgia Habitat selection lynx rufus Pinus palustris Prescribed fire

New players in the regulation of ecdysone biosynthesis

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j.urnal of Genetics and Genomics 2008年第1期35卷 1-10页

作者： Xun Huang j.mes T. warren lawrence I. Gilbert laboratory of Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Department of Biology University of North Carolina at Chapel Hill Chapel Hill NC 27599-3280 USA

Insect ecdysone steroid hormone regulates maj.r developmental transitions, such as molting and metamorphosis. The production of ecdysone correlates well with the timing of these transitions. Finding out how the ecdysone biosynthesis is regulated is crucial to fully understand these sophisticated developmental switches. Here we summarized recent findings in the regulation of ecdysone biosynthesis from the aspects of cell signaling, key biosynthetic enzymes and substrate cholesterol trafficking.

关键词： ecdysone cholesterol PTTH P450

The Impact of Omega-3 Fatty Acid Use on the Risk of Atrial Fibrillation in Patients with Cardiovascular Disease

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International j.urnal of Clinical Medicine 2011年第1期2卷 23-27页

作者： Brian j. Barnes Patricia A. Howard Scott Solomon warren Chen j.mes l. Vacek 不详

Fish oils containing omega-3 fatty acids (OM3FA) are widely prescribed in the management of dyslipidemia. An asso-ciation between OM3FA and reduced risk of atrial fibrillation (AF) has been proposed. We examined the impact of OM3FA exposure on the risk of developing AF in patients with cardiovascular disease. Data was obtained from elec-tronic medical records of patients seen by our cardiology service between 2005 and 2007. Patients were excluded if AF developed prior to, or on the day of, OM3FA exposure. A total of 11,360 subj.cts were eligible for analyses. Subj.cts exposed to OM3FA were at higher risk for AF. Nearly all AF risk factors were significantly more prevalent in the OM3FA exposed group. As expected, those prescribed OM3FA were also more likely to be prescribed statins, ACE in-hibitors, aspirin, and beta blockers. AF occurred in 8.5% (221/2600) of OM3FA exposed subj.cts and 23.5% (2054/8760) of those not exposed. After controlling for AF risk factors, OM3FA exposed subj.cts were 74% less likely to develop AF than those not exposed to OM3FA (odds ratio 0.26, 95%CI 0.22-0.30, p lling for risk factors for AF, OM3FA use is significantly associated with a reduced risk for AF in patients with cardiovascular disease. Potential mechanisms which may explain the ability of OM3FAs to reduce AF include its anti-inflammatory and anti-arrhythmic properties. The optimal dose of OM3FA to prevent AF is unknown and warrants prospective as-sessment in a randomized controlled trial of OM3FAs powered to detect significant differences in AF.

关键词： Omega-3 Fatty Acids Atrial Fibrillation

An automated multiwell plate reading flim microscope for live cell autofluorescence lifetime assays

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j.urnal of Innovative Optical Health Sciences 2014年第5期7卷 99-113页

作者： Douglas j.Kelly Sean C.warren Sunil Kumar j.ao l.lagarto Benj.min T.Dyer Anca Margineanu Eric W.-F.lam Chris Dunsby Paul M.W.French Photonics Group Department of PhysicsImperial College London South Kensington CampusLondonSW72AZUK Institute of Chemical Biology Department of Chemistry Imperial College LondonSouth Kensington Campus LondonSWT 2AZUK National Heart&lung Institute Imperial Centre for Eaperimental&Translational Medicine Du Cane Road LondonW12 ONNUK Department of Surgery and Cancer Imperial Cllege London Du Cane RoadLondonW12 ONNUK Centre for Histopathology Imperial College London Du Cane RoadLondonW120NNUK

Fluorescence lifetime imaging(FlIM)is increasingly used to read out cellular autofluorescenceoriginating from the coenzyme NADH in the context of investigating cell metabolic *** here an automated multiwell plate reading FlIM microscope optimized for UV illumi-nation with the goal of extending high content fluorescence lifetime asays to readouts ofmetabolism,We demonstrate its application to automated cellular autofluorescence lifetime imaging and discuss the key practical issues associated with its *** particular,weillustrate its capability to read out the NADH-lifetime response of cells to metabolic modulators,thereby illustrating the potential of the instrument for cytotoxicity studies,assays for drugdiscovery and stratified medicine.

关键词： High content analysis FlIM NADH metabolism cisplatin.

监测浸金过程氰化物消耗的研究——氰离子电极性能的评价

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黄金 1997年第10期18卷 35-39页

作者：李希明 D.C.Wright l.j.warren 中国科学院化工冶金研究所 DivisionofMineralProductsCSIRO Australia

为寻找有效的监测手段以降低氰化浸金的试剂消耗,评价了两种商业电极“Kegold”和“Orion”氰离子电极的性能,对电极响应和氰离子浓度变化进行线性关联,研究了溶液pH和温度变化对电极响应的影响,并比较了两种电极的测量误差。研究表明,... 详细信息

为寻找有效的监测手段以降低氰化浸金的试剂消耗,评价了两种商业电极“Kegold”和“Orion”氰离子电极的性能,对电极响应和氰离子浓度变化进行线性关联,研究了溶液pH和温度变化对电极响应的影响,并比较了两种电极的测量误差。研究表明,用氰离子电极监测氰化物浓度变化是可行的。在深入研究干扰因素影响的基础上,优化工作条件能进一步改善其测量精确度。

关键词：浸金氰离子电极氰化物炼金测量误差

氰化浸金过程氰化物消耗的监测——硫、砷离子对氰离子电极行为的影响

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黄金 1999年第10期20卷 30-34页

作者：李希明 D.C.Wright l.j.warren 国家经贸委黄金管理局 DivisionofMineralProducts.CSRO

讨论了两类氰离子电极的工作原理，列举了可能的干扰反应，并在此基础上探讨了硫、砷离子对工作电极的影响。实验结果表明，二价硫离子对测量有严重干扰，三价砷则无不良影响。化学分析证实，氰离子电极能正确响应元素硫、Ｓ２Ｏ２－３... 详细信息

讨论了两类氰离子电极的工作原理，列举了可能的干扰反应，并在此基础上探讨了硫、砷离子对工作电极的影响。实验结果表明，二价硫离子对测量有严重干扰，三价砷则无不良影响。化学分析证实，氰离子电极能正确响应元素硫、Ｓ２Ｏ２－３、ＳＯ２－３、ＳＣＮ－和ＯＣＮ－存在时溶液氰离子浓度的变化。除元素硫之外，其它干扰离子通常在浸金过程中含量都很低，故其影响可不予考虑。

关键词：氰化物监测氰离子电极硫化物氰化浸金