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Impact of patch size on woody tree species richness and abundance in a tropical montane evergreen forest patches of south India

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journal of Forestry Research 2018年第6期29卷 1675-1687页

作者： Dharmalingam Mohandass Mason j.Campbell priya Davidar Root and Soil Biology Laboratory Department of BotanyBharathiar UniversityCoimbatoreTaminadu 641046India Centre for Tropical Environmental and Sustainability Science(T.E.S.S.) College of Science and EngineeringJames Cook UniversityCairnsQLD 4870Australia Department of Ecology and Environmental Sciences Pondicherry UniversityKalapetPondicherry 605014India

We examined the effects of forest patch size on woody tree species richness and abundance in tropical montane evergreen forest patches of the Nilgiri region,south India. We sampled woody trees(>1 cm dbh) from 21 forest patches in the upper Nilgiri hills(> 2000 m elevation) and recorded a total of 35,146 individuals of 61 species, 45 genera and 30 families. Species richness and abundance of sapling/shrubs(≥ 1 to patch size, but the species richness and abundance of small, medium and larger trees(≥ 10 to pectively) did not. Overall, forest interior species richness and abundance increased significantly with increasing patch size but edge species richness did not. Species richness and abundance of shade-tolerant and shade-demanding tree species also increased with increasing patch size. The abundance of zoochory dispersed tree species was significantly related to increasing patch size, but those dispersed by autochory did not display any clear relationship between patch size and species richness or *** findings suggest that with increasing forest patch area,tree compositional patterns may be driven by species specific shade-tolerance adaptations and dispersal *** responses in these traits by the plant community within the individual habitat zones of forest edge and interiors likely plays a major role in determining the inherent plant community and thus the subsequent ecological processes of forest patches, including their responses to increasing patch area.

关键词： Dispersal mode Forest fragments Shade-tolerance Species–area relationships Western Ghats

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Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes （Siluriformes： Doradidae, Auchenipteridae）： potential morphological correlates

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Current Zoology 2012年第1期58卷 171-188页

作者： Kaatz, Ingrid M. Stewart, Donald j. Department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry Syracuse NY 13210 USA

Swimbladder disturbance sounds of doradoid catfishes （Doradidae and Aucheniptefidae） demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms （lacking interpulses） or pulsed （groups of pulses repeated at fixed temporal intervals）. This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included： swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for po- tential correlates of call diversity are： 1） diverticula （marginal outpocketings of the swimbladder with no connection to inner ear） and 2） elastic spring apparatus Mtillerian rami （ESA-Mr）. Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swim- bladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant fre- quency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with out- group taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species repre- senting outgroup families produced either continuous lower dominant frequency sounds （aspredinids, mochokids and pseudopimelodids） or pulsed higher dominant frequency sounds （pimelodids） [Current Zoology 58 （1）： 171-188, 2012].

关键词： Catfishes Communication Signal evolution Vocal mechanisms

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Experimental Study and Numerical Simulation of the Casting-Forging Complex Near Net Forming of Alternator Claw-pole

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上海交通大学学报 2004年第Z2期38卷 79-82页

作者： j.L.Song D.j.Hu Q.C.Wang H.Q.Chen H.G.Guo School of Mechanical and power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai200030 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China Scool of Materials Science and Engineering Taiyuan Heavy Machinery Institute Taiyuan030024 China

As a newly developed precision technology, casting-forging complex near net forming process is utilized to produce complex components with a short lead time, low cost and high precision, thus to accelerate the response speed of the market and enhance the competitive power of products. In this paper, the casting-forging complex near net forming process of alternator claw pole was developed and investigated with a combination of experimental and numerical simulation method. Qualified near net workpiece was manufactured, mechanical parameter and relative field information during the forming process was also obtained. While the alternator claw-pole is processed with this technology, the forming force is small, the process is short and the quality of forgings is perfect. Therefore, the complex casting-forging near net forming process of claw-pole is an energy and material saving technology, which will have a vast developing and application prospect in the future.

关键词： alternator claw-pole casting-forging near net forming numerical simulation

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Recent advances in the study of Mesozoic-Cenozoic petrified wood from Thailand

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progress in Natural Science:Materials International 2006年第5期16卷 501-506页

作者： pratueng jINTASAKUL paul j.GROTE Nareerat BOONCHAI Northeastern Research Center and Museum for petrified Wood and Mineral Resources Nakhon Ratchasima 30000 Thailand Geography ProgramNakhon Ratchasima Rajabhat UniversitySuranarai RoadMuang DistrictNakhon Ratchasima 30000Thailand School of Biology Institute of Science Suranaree University of TechnologyNakhon Ratchasima 30000Thailand Northeastern Research Center and Museum for petrified Wood and Mineral Resources Nakhon Ratchasima 30000 Thailand School of BiologyInstitute of ScienceSuranaree University of TechnologyNakhon Ratchasima 30000Thailand

Mesozoic to Cenozoic petrified woods are very rich and well preserved in the Khorat plateau, Northeast Thailand, serving as remarkable material for investigations of tropical vegetation history, paleoclimatic evolution, and paleoenvironmental changes. Our recent field survey and investigations have defined about 50 species of fossil wood assigned to 19 genera and 11 families from Mesozoic to Cenozoic deposits in this region. These woods are ascribed to two groups, gymnosperms and angiosperms. Among them, about 20 species assigned to 7 genera and 5 families are the first reports of the taxa in Thailand. The fossil wood floras indicate that during the late Mesozoic period, the tropical conifer vegetation in Northeast Thailand was dominated by the family Araucariaceae. From the Miocene to pleistocene, a tropical climate prevailed in this region with perhaps both deciduous and evergreen broadleaf forests comprising the vegetation.

关键词： fossil wood tropical vegetation Mesozoic Cenozoic Thailand.

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Genetic alteration and mutation profiling of circulating cell-free tumor DNA(cfDNA) for diagnosis and targeted therapy of gastrointestinal stromal tumors

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Chinese journal of Cancer 2016年第7期35卷 342-349页

作者： Weixin Yan Aiguo Zhang Michael j.powell Robotics Research Institute School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240P.R. China DiaCarta Inc. 2600 Hilltop Drive Richmond CA 94806USA

Gastrointestinal stromal tumors(GISTs) have been recognized as a biologically distinctive type of tumor,different from smooth muscle and neural tumors of the gastrointestinal *** identification of genetic aberrations in proto-oncogenes that drive the growth of GISTs is critical for improving the efficacy of cancer therapy by matching targeted drugs to specific *** into the oncogenic mechanisms of GISTs has found that these tumors frequently contain activating gene mutations in either platelet-derived growth factor receptor A(pDGFRA) or a receptor tyrosine protein associated with a mast cell growth factor receptor encoded by the KIT *** cancer subpopulations have the potential to disrupt durable patient responses to molecularly targeted therapy for GISTs,yet the prevalence and size of subpopulations remain largely *** of the cancer subpopulations that harbor low-frequency mutant alleles of target proto-oncogenes through the use of molecular genetic methods,such as polymerase chain reaction(pCR) target amplification technology,is hampered by the high abundance of wildtype alleles,which limit the sensitivity of detection of these minor mutant *** is especially true in the case of mutant tumor DNA derived "driver" and "drug-resistant" alleles that are present in the circulating cell-free tumor DNA(cfDNA) in the peripheral blood circulation of GIST ***-called "liquid biopsy" allows for the dynamic monitoring of the patients' tumor status during treatment using minimally invasive *** methodologies,such as a technology that employs a xenonucleic acid(XNA) clamping probe to block the pCR amplification of wild-type templates,have allowed improved molecular detection of these low-frequency alleles both in tissue biopsy samples and in *** new methodologies could be widely applied for minimally invasive molecular testing in the therapeutic management of GISTs.

关键词：基因突变检测肿瘤治疗靶向治疗遗传变异肥大细胞胃肠道 DNA 间质

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Effect of ethanol on pro-apoptotic mechanisms in polarizedhepatic cells

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World journal of Gastroenterology 2007年第37期13卷 4960-4966页

作者： Benita L McVicker Dean j Tuma Carol A Casey Liver Study Unit Department of Veterans Affairs Medical Center and Departments of Internal Medicine and Biochemistry & Molecular Biology University of Nebraska Medical Center Omaha NE 68105 United States

Chronic ethanol consumption is associated with serious and potentially fatal alcohol-related liver injuries such as hepatomegaly, alcoholic hepatitis and cirrhosis. Moreover, it has been documented that the clinical progression of alcohol-induced liver damage may be associated with an increase in hepatocellular death that involves apoptotic mechanisms. Although much information has been learned about the clinical manifestations associated with alcohol-related diseases, the search continues for a better understanding of the molecular and/or cellular mechanisms by which ethanol exerts its deleterious effects such as the induction of pro-apoptotic mechanisms and related cell damaging events. As part of the effort to enhance our understanding of those particular cellular pathways and mechanisms associated with ethanol toxicity, researchers over the years have utilized a variety of model systems. Recently, work has come forth demonstrating the utility of a hybrid cell line (WIF-B) as a cell culture model system for the study of alcohol-associated alterations in hepatocellular mechanisms. Success with such emerging model systems could aid in the development of potential therapeutic treatments for the prevention of alcohol- induced apoptotic cell death that may ultimately serve as a significant target in delaying the onset and/or progression of clinical symptoms of alcohol-mediated liver disease. This review article summarizes the current understanding of ethanol-mediated modifications in cell survival and thus the promotion of pro-apoptotic events with emphasis on analyses made in various experimental model systems, particularly the more recently characterized WIF-B cell system.

关键词： Hepatoma hybrid cells Ethanol Apoptosis Fas receptor Caspase

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Understanding the El Nio Costero of 2017: The Definition problem and Challenges of Climate Forecasting and Disaster Responses

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International journal of Disaster Risk Science 2017年第4期8卷 489-492页

作者： Ivan j.Ramírez Fernando Briones Department of Anthropology Colorado State University Consortium for Capacity Building/INSTAAR University of Colorado Graduate program in public Health Colorado State University

This preliminary study examines the definition problem and challenges of climate forecasting and disaster responses associated with the El Nio costero(coastal) of2017, which developed rapidly with no warning and had catastrophic effects in peru. Such a localized El Nio was not documented since 1925. An initial review suggests that in addition to the characteristics of the event(surprise),government responses may have been inadequate(as media reported) because of conflicting forecast reports(U.S. and peru), which provoked a hydrometeorological debate and stifled decision making. partly to blame was the El Nio definition problem, which can cause uncertainty and affect perception of risk, depending on which region of the equatorial pacific one uses to identify an event. Responses were further complicated by the fact that some regions within peru were experiencing drought prior to the El Nio costero's onset and impacts from the El Nio 2015–2016 were less than expected. Furthermore, a new government was in place, which may have hindered action. Thus, El Nio costero provides lessons to heed, not only with respect to the forecast information, but also with reference to the context of the forecast and disaster setting, which can influence disaster responses to hydrometeorological threats.

关键词： Disaster risk reduction Ecuador El Nio costero El Nio forecast El Nio-Southern Oscillation peru Teleconnections

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美国肉鸡生产中的氮平衡应用研究

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中国家禽 2010年第13期32卷 31-35页

作者： C.p.Coufal C.Chavez p.R.Niemeyer j.B.Carey 吕玲美国德克萨斯州农工大学家禽科学系

正确处理粪便防止营养流失是家禽养殖者长期以来面对的难题。在过去几十年里家禽养殖规模越来越大，而且越来越集中，导致营养以粪便的形式高度集中和以废气形式排放。废气排放中的营养问题，主要是以氨气形式排放的氮。大量氨气排放到... 详细信息

正确处理粪便防止营养流失是家禽养殖者长期以来面对的难题。在过去几十年里家禽养殖规模越来越大，而且越来越集中，导致营养以粪便的形式高度集中和以废气形式排放。废气排放中的营养问题，主要是以氨气形式排放的氮。大量氨气排放到空气中导致负面的环境影响使之成为一个重要的问题。氨气可能导致土壤和生态系统中的氮饱和、水表面富营养化、土壤酸化、森林覆盖率下降、生态系统多样化消失以及形成悬浮微粒（pM25）导致空气污染。

关键词：废气排放氮平衡肉鸡生产检测应用美国营养流失家禽养殖

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新料覆盖法在肉鸡生产中的应用

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中国家禽 2010年第13期32卷 35-37页

作者： C.p.Coufal C.Chavez p.R.Niemeyer j.B.Carey 吕玲美国德克萨斯州农工大学家禽科学系

现代肉鸡生产中结块垫料经常出现在饮水器或蒸发冷却系统附近，在禽舍转入下一批鸡之前需要采用机械进行清理。如果更多的鸡饲养在相同的垫料上的话，垫料的吸收能力就会下降，结块垫料比例会增加。采用回收垫料进行新料覆盖是一种常用... 详细信息

现代肉鸡生产中结块垫料经常出现在饮水器或蒸发冷却系统附近，在禽舍转入下一批鸡之前需要采用机械进行清理。如果更多的鸡饲养在相同的垫料上的话，垫料的吸收能力就会下降，结块垫料比例会增加。采用回收垫料进行新料覆盖是一种常用于商品化生产体系的垫料处理方法，可以延长垫料的使用时问和整个禽舍的完全清理间隔。加入新鲜的干燥垫料（湿度为10％）可提高垫料的吸收能力和降低结块垫料的形成。

关键词：肉鸡生产覆盖法垫料处理应用蒸发冷却系统吸收能力生产体系饮水器

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动力系统的稳定性

动力系统的稳定性

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丛书名：现代应用数学

2002年

作者：（美） j. p. LaSalle 陆征一译

来源：汇雅图书（南通市图书馆... 评论

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