检索结果-南通市图书馆

Dimorphism of Bivalved Arthropod Branchiocaris？ Yunnanensis from the Early Cambrian Chengjiang Biota, South China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2016年第3期90卷 818-826页

作者： WU Yu FU Dongjing ZHANG Xingliang Allison C. DALEY SHU Degan Early Life Institute and State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi 'an 710069 China Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK oxford University Museum of Natural History Parks Road Oxford OX1 3PW UK

The bivalved arthropod Branchiocaris？ yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The carapace comprises two identical valves, each valve are sub-circular in outline, ranging from 24 mm to 58 mm in length, and from 15 mm to 46 mm in height. The dorsal margin is straight and bears two short cardinal spines. The valve surface is either smooth or ornamented with polygonal reticular structures, which may result from different preservation conditions. Two morphotypes have been recognized based on the presence or absence of a subdorsal swelling of the valve, which is convex dorsolaterally and extends beyond the dorsal margin when it appears. Statistic and ontogenetic analyses show both morphotypes grow isometrically and have the same growth trajectory. Therefore, the two morphotypes are interpreted as dimorphism within the same species. Our results are helpful for investigating the taxonomy and ontogeny of arthropod fossils and suggest that dimorphism might be fairly common in these early arthropods.

关键词： Arthropoda Branchiocaris Dimorphism Ontogeny Chengjiang biota

Exploration of unpredictable environments by networked groups

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2016年第3期62卷 207-214页

作者： Takao SASAKI Marco A. JANSSEN Zachary SHAFFER Stephen C. PRATT School of Life Sciences and Center for Social Dynamics and Complexity Arizona State University Tempe AZ 85287-4501 USA Department of Zoology University of Oxford OX1 3PS UK School of Sustainability and Center for Behavior Institutions and the Environment Arizona State University Tempe AZ 85287-5502 USA

Information sharing is a critical task for group-living animals. The pattern of sharing can be modeled as a network whose structure can affect the decision-making performance of individual members as well as that of the group as a whole. A fully connected network, in which each member can directly transfer information to all other members, ensures rapid sharing of important information, such as a promising foraging location. However, it can also impose costs by amplifying the spread of inaccurate information (if, for example the foraging location is actually not profitable). Thus, an optimal network structure should balance effective sharing of current knowledge with opportunities to discover new information. We used a computer simulation to measure how well groups characterized by different network structures (fully connected, small world, lattice, and random) find and exploit resource peaks in a variable environment. We found that a fully connected network outperformed other structures when resource quality was predictable. When resource quality showed random variation, however, the small world network was better than the fully connected one at avoiding extremely poor outcomes. These results suggest that animal groups may benefit by adjusting their information-sharing network structures depending on the noisiness of their environment.

关键词：网络结构环境资源群体生活信息共享小世界网络工作结构随机变化计算机模拟

从白符虫兆(弹尾纲)活性卵的形状变化探讨沃尔巴克氏体的共生作用(英文)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2010年第6期31卷 623-626页

作者： Nina Hafer Nathan Pike Department of Zoology University of Oxford Tinbergen Building South Parks Road Oxford OX1 3PS UK

Wolbachia属共生菌的侵染是引起跳虫——白符虫兆孤雌生殖的原因。对带有正常沃尔巴克氏体菌群的白符虫兆卵和通过利福平处理剔除沃尔巴克氏体菌群的白符虫兆卵的胚胎发育进行实验观察。白符虫兆的活性卵产出3到4天后,卵体大小显著性地... 详细信息

Wolbachia属共生菌的侵染是引起跳虫——白符虫兆孤雌生殖的原因。对带有正常沃尔巴克氏体菌群的白符虫兆卵和通过利福平处理剔除沃尔巴克氏体菌群的白符虫兆卵的胚胎发育进行实验观察。白符虫兆的活性卵产出3到4天后,卵体大小显著性地增大,并伴随卵体形状从球形到圆饼形的变化。这些变化在利福平处理的或者是7%自然失活的非活性卵中都没有出现。推测沃尔巴克氏体在白符虫兆卵产出后的3天之内或者3天之前的受精卵发育或胚胎发育中发挥着重要作用;同时根据目前已有的研究结果推断沃尔巴克氏体对白符虫兆卵发育可能的影响机制。

关键词：孤雌生殖胚胎发育弹尾纲孵化率

Molecular biology:a future role in the control of the cotton pest,the pink bollworm（Pectinophora gossypielia）?

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Molecular biology:a future role in the control of the cotton...

21st IUBMB and 12th FAOBMB International Congress of Biochemistry and Molecular Biology

作者： LI Jin Adam Walker Neil Morrison Guollang Fu Luke Alphey Department of Zoology University of OxfordSouth Parks RoadOxford OX1 3PSUK

＜正＞Techniques in molecular biology are being increasingly used for pest control. Here,we describe the application of molecular cloning and genetic modification to potentially improve the sterile insect technique（SIT）,in whicli large numbers of sterile insects are released as a means of environmentally friendly pest *** form of SIT,called Release of Insects carrying a Dominant

关键词：

The trade-off between individual foraging and predation risk by granivorous birds feeding in different micro-habitats

在线全文

cnki会议

学校读者我要写书评

暂无评论

The trade-off between individual foraging and predation risk...

23rd International Ornithological Congress

作者： Mark J.Whittingham Simon J.Butler Will Cresswell John Quinn Edward Grey Institute for Ornithology Department of Zoology Oxford University South Parks Road Oxford OX I 3PSUK Edward Grey Institute for Ornithology Department of Zoology Oxford University South Parks Road Oxford OX I 3PSUK Edward Grey Institute for Ornithology Department of Zoology Oxford University South Parks Road Oxford OX I 3PSUK Edward Grey Institute for Ornithology Department of Zoology Oxford University South Parks Road Oxford OX I 3PSUK

＜正＞ Habitat selection by foraging birds is constrained by not only food density but also other factors including field of view of approaching predators. Wintering granivorous birds are known to strongly select stubble fields （i.e. fields left fallow after harvest）. We created two swards one typical of stubble fields （height, 13cm） and the other identical in density but shorter in height （3 cm）. We examined foraging behaviour and escape response to a

关键词： Foraging sward structure access vs availability predation risk

Environmental and ecological correlates of species richness in non-passerine birds

在线全文

cnki会议

学校读者我要写书评

暂无评论

Environmental and ecological correlates of species richness ...

23rd International Ornithological Congress

作者： Walter Jetz Department of Zoology University of Oxford OX1 3PS Oxford UK Biology Department University of New Mexico Albuquerque NM 87131 USA

＜正＞ The factors that influence rates of speciation and ultimately the phylogenetic and current geographic pattern in species richness are still poorly understood. A plethora of hypotheses has been put forward to explain species richness gradients, many of them overlapping or untestable. The most prominent hypotheses stress the roles of productivity, habitat heterogeneity and regional history. Here we attempt a fresh approach to comprehend the

关键词： species richness non-passerines global speciation synthetic analysis

Population structure and body condition of White-crested Elaenia(Elaenia albiceps)in relation to habitat in a modiffed Neotropical forest landscape

在线全文

cnki会议

学校读者我要写书评

暂无评论

Avian Research 2023年第2期14卷 160-165页

作者： Roberto F.Thomson Andrew G.Gosler Edward Grey Institute of Field Ornithology Department of ZoologyUniversity of OxfordSouth Parks RoadOX13PSOxfordUK Laboratorio de Ecología de Vida Silvestre Facultad de Ciencias Forestales y Conservacion de la NaturalezaUniversidad de ChileSanta Rosa#11315La PintanaRegion MetropolitanaChile Institute of Human Sciences The Pauling Centre58a Banbury Rd.OxfordOX26QSUK

Despite the widely accepted view that planted forests are valuable habitat for wildlife species,there is a lack of empirical evidence showing the suitability of this novel habitat,especially in relation to plantations of exotic tree ***,little is known about the effects of forest management on the ecology and dynamics of wild populations in the *** the breeding season,the migrant flycatcher White-crested Elaenia is the most abundant bird species in forested landscapes in *** several years we have studied different aspects of these artificial forests in the coastal range of south-central Chile as habitat for the species,particularly in contrast to the native *** general,our results indicate that plantation forests offer a poorer quality habitat,where the density of the species tends to be lower than in the native forest,although a significant edge effect suggests that its quality can be mitigated by planting as a matrix mosaic with native ***,compared to native forests,populations in plantations contained a higher proportion of younger adult individuals maintaining larger territories,and showing poorer body *** suggest that these differences could also have an impact on the birds'longevity and survival.

关键词： Body condition Migrant Planted forests Survival Temperate forests Territory

HABITAT PARTITIONING IN SYMPATRJC GALAGO SPECIES IN TANZANIA

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

HABITAT PARTITIONING IN SYMPATRJC GALAGO SPECIES IN TANZANIA

The Xixth Congress The International Primatological Society

作者： PaulE.Honess Department of Veterinary Services University of Oxford Oxford OX13PT UK. and Wildlife Conservation Research Unit Department of Zoology University of Oxford Oxford OX1 3PS UK.

＜正＞ Three species of galago （Primates;Galagidae） are found in the Rondo Forest Reserve, Lindi Region, South East Tanzania: Garnett’s galago （Otolemur garnettii）, Grant’s galago （Galagoides granti） and the newly described Rondo galago （Galagoides rondoensis）. Competition theory tells us that no two sympatric species can occupy the same ecological niche at the same time. During the course of a more

关键词： Galago substrate use Tanzania.

Applications of RNA interference highthroughput screening technology in cancer biology and virology

在线全文

cnki会议

学校读者我要写书评

暂无评论

Protein & Cell 2014年第11期5卷 805-815页

作者： Shan Gao Chen Yang Shan Jiang Xiao-Ning Xu Xin Lu You-Wen He Annie Cheung Hui Wang Department of Oncology John Radcliffe Hospital Weatherall Institute of Molecular Medicine University of Oxford Oxford OX3 9DS UK Department of Molecular Genetics and Microbiology Stony Brook University Stony Brook NY 11794 USA Department of Immunology Duke University Durham NC 27708 USA Department of Immunology Chelsea & Westminster Hospital Imperial College of London 369 Fulham Road London SW10 9NH UK Nuffield Department of Clinical Medicine Ludwig Institute for Cancer Research Oxford Branch University of Oxford Old Road Campus Research Building Oxford OX3 7DQ UK Department of Pathology Queen Mary Hospital University of Hong Kong Pokfulam Road Hong Kong China Natural Environment Research Council Centre for Ecology & Hydrology Benson Lane Wallingford Oxfordshire OX10 8BB UK Department of Zoology University of Oxford South Parks Road Oxford OX1 3PS UK

RNA interference （RNAi） is an ancient intra-cellular mechanism that regulates gene expression and cell function. Large-scale gene silencing using RNAi highthroughput screening （HTS） has opened an exciting frontier to systematically study gene function in mammalian cells. This approach enables researchers to identify gene function in a given biological context and will provide considerable novel insight. Here, we review RNAi HTS strategies and applications using case studies in cancer biology and virology.

关键词： RNA interference (RNAi) short interferingRNA (siRNA) short hairpin RNA (shRNA) high-throughputscreening cancer virology