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A test of genetic association among male nuptial coloration, female mating preference, and male aggression bias within a polymorphic population of cichlid fish

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Current Zoology 2013年第2期59卷 221-229页

作者： Inke van der SLUIj. Peter D. DIj.STRA Charlotte M. LINDEYER BertanneVISSER Alan M. SMITH Ton G. G. GROOTHUIS j.cques j. M. van ALPHEN Ole SEEHAUSEN Department of Animal Ecology Institute of Biology Leiden University PO Box 9516 2300 RA Leiden The Netherlands The University of Texas at Austin Section of Integrative Biology 1 University Station-C0930 Austin TX 78712 United States Department of Biological Sciences University of Hull Cottingham Road Hull HU6 7RX United Kingdom Behavioural Biology Group University of Groningen P.O. Box 14 9750 AA Haren The Netherlands Institute of Zoology University of Bern Baltzerstrasse CH-3012 Bern Switzerland Eawag Swiss Federal Institute for Aquatic Science and Technology Centre of Ecology Evolution & Biogeochemistry Depart- ment ofFish Ecology & Evolution Seestrasse 97 6047 Kastanienbaum Switzerland

Both inter- and intrasexual selection have been implicated in the origin and maintenance of species-rich taxa with di- verse sexual traits. Simultaneous disruptive selection by female mate choice and male-male competition can, in theory, lead to ~,;peciation without geographical isolation if both act on the same male trait. Female mate choice can generate discontinuities in gene flow, while male-male competition can generate negative frequency-dependent selection stabilizing the male trait polymor- phism. Speciation may be facilitated when mating preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations among female mating preference, male aggression bias and male coloration in the Lake victoria cichlid Pundamilia. We crossed females from a phenotypically variable population with males from both extreme ends of the phenotype distribution in the same population （blue or red）. Male offspring of a red sire were significantly redder than males of a blue sire, indicating that intra-population variation in male coloration is heritable. We tested mating preferences of female offspring and aggression biases of male offspring using binary choice tests. There was no evidence for associations at the family level between female mating preferences and coloration of sires, but dam identity had a significant effect on female mate prefe- rence. Sons of the red sire directed significantly more aggression to red than blue males, whereas sons of the blue sire did not show any bias. There was a positive correlation among individuals between male aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the maintenance of color polymorphism [Current Zoology 59 （2）： 221-229, 2013].

关键词： Disruptive selection Sexual selection Speciation Pundamilia Linkage disequilibrium

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加拿大不列颠哥伦比亚省温哥华岛纳奈莫群的帆翼龙类化石(英文)

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地球学报 2010年第S1期31卷 3-3页

作者： victoria M.ARBOUR Philip j.CURRIE Laboratory for Vertebrate Paleontology Department of Biological SciencesUniversity of Alberta

An unusual j.w found in a calcite nodule from Collishaw Point,Hornby Island,British Columbia(off the east coast of Vancouver Island)represents the first definitive

关键词：不列颠哥伦比亚省加拿大温哥华类化石翼龙

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Biometrics and wing molt in White-winged Black Tern (Chlidonias leucopterus) in north-west Australia

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Chinese Birds 2013年第4期4卷 306-313页

作者： Peter j. FULLAGAR Michael j. DAWKINS Clive D. T. MINTON Unit 1/11 j.y Cummings Place Belconnen ACT 2617 Australia 15 The Boulevarde Wy Yung Victoria 3875 Australia 165 Dalgetty Road Beaumaris Victoria 3193 Australia

We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this species yet reported from Australia. When comparing j.veniles with adults, only wing length and body mass differed significantly; however, j.veniles were still easily recognized by plumage and wing molt as late as March. There was little evidence of any dramatic weight gain in adults before their northward migration. No morphological characteristic distinguishing sex was found. We confirmed that terns caught in this study did not appear to differ morphologically from those of the western palearctic populations. We describe wing molt based on data from 354 individuals captured and banded in Australia over 28 years. Wing molt proceeds in much the same way as found in other small terns.

关键词： White-winged Black Tern morphometrics wing molt Australia feeding roosting

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Geographical Variation, Distribution and Diversity of <i>Rice Yellow Mottle Virus</i>Phylotypes in Tanzania

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American j.urnal of Plant Sciences 2017年第6期8卷 1264-1284页

作者： j.dith Hubert Herman j. F. Lyimo Ashura Luzi-Kihupi Department of Crop Science and Production Sokoine University of Agriculture Morogoro Tanzania

Rice yellow mottle virus (RYMV) is the most important disease of rice in Africa. The disease was first observed in1966 inKenya but has now spread in all rice-growing countries of Sub-Saharan Africa. In Tanzania, its distribution has been restricted to the maj.r rice-growing regions. However, the knowledge on RYMV genetic diversity relies on a limited number of coat protein sequences. Previous studies revealed the presence of the phylotypes S4lv, S4lm and strain S5 in Mwanza, Mbeya and Morogoro regions, respectively, and strain S6 in Kilimanj.ro region and Pemba Island. Surveys were conducted during the cropping seasons 2013-2014 in eight rice-growing regions of Tanzania to determine geographical variations and phylotypes of RYMV and the influence of environment factors on its distribution and diversity. A total of 185 rice fields were surveyed. Results indicate that prevalence, severity and phylotypes of RYMV varied significantly with rainfall intensity, temperature and relative humidity (P ≤ 0.01). The highest prevalence was found in Morogoro (82%), Mbeya (80%) and Arusha (67.33%) regions whereas Kigoma (9.33%), Rukwa (11.33%) and Shinyanga (18.67%) had the lowest RYMV prevalence. In each region, RYMV prevalence was higher in 2014 than in 2013. The phylotypes S4lm and new determined phylotypes (S6c and S6w) were highly adapted to low temperature (13.3°C) and rainfall (13.7 mm) areas. For the first time, strains from the phylotype S4ug were found outside Uganda, in Kilimanj.ro region. Strain S4lv (phylotype Lake victoria) was found for the first time in Arusha region. The strain S4lm was found in Mbeya, Morogoro and Rukwa regions. Strains S4lm and S4lv were also found in Shinyanga and Kigoma regions, respectively. The strain S5 was still restricted to Morogoro but extended to new locations such as Ulanga district. Strain S6 was found in several new areas and new phylotypes of S6 (S6c and S6w) are reported in this study.

关键词： Rice Yellow Mottle Virus Prevalence Severity Environmental Factors Tanzania

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Cyperus papyrus L. Growth Rate and Mortality in Relation to Water Quantity, Quality and Soil Characteristics in Nyando Floodplain Wetland, Kenya

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Open j.urnal of Ecology 2016年第12期6卷 714-735页

作者： P. j. K. Rongoei N. O. Outa Department of Environmental Science Egerton University Njoro Kenya Department of Biological Sciences Egerton University Njoro Kenya

Cyperus papyrus (L.) growth rate and mortality is influenced by environmental conditions prevailing in the wetland. To assess growth dynamics of C. papyrus in relation to water depth and anthropogenic (exploitation) pressures, monthly and bi-monthly measurement of culm length and girth were done between j.ne and December 2010 (period 1) and April to j.ne 2011 (period 2). Three study sites were selected based on the water levels and livelihood-driven exploitation pressures. Surrogate measurements of individual culm height and girth were done in three 1 m2 quadrats in each site to determine the growth rate of papyrus. Water depth was lowest in period 2 (dry) and highest in period 1 (wet) which was related to the livelihood activities being highest in period two and lowest in period one. Culm mortality occurred throughout the study period with 64% due to natural senescing while insect/rodent accounted for 19%. Papyrus growth was higher in Singida (2.5 ± 0.2 cm/day) representing less disturbed site and least in Wasare (1.4 ± 0.1 cm/day) which was highly disturbed. Multiple regression models for culm length showed culm density, mean length and NH4 negatively influenced growth rate while site as a dummy variable, water depth, SRP and TP had positive effects on papyrus growth rate. Understanding growth rate and causes of mortality in papyrus is important to establish sustainable management strategies of this ecosystem to maintain its integrity.

关键词： Water Depth Density Multiple Regression Models Lake victoria Wetlands Kenya

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关于废除社区在流感大流行期间实行的减灾策略

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中国人兽共患病学报 2008年第5期 386-386页

作者： victoria j.Davey Robert j.Glass 修文琼张拥军福建省疾病预防控制中心

我们通过网络计算模型,评估一次流感大流行后在两个社区废除减灾策略的阈值。当两个级别的大流行(共有5级,其中第5级与1918年流感类似)发病率在7天内消退到0,1,2或3个病例的阈值时结束对儿童的隔离或对所有社区的隔离。以一次未进行减... 详细信息

我们通过网络计算模型,评估一次流感大流行后在两个社区废除减灾策略的阈值。当两个级别的大流行(共有5级,其中第5级与1918年流感类似)发病率在7天内消退到0,1,2或3个病例的阈值时结束对儿童的隔离或对所有社区的隔离。以一次未进行减灾的疫情或在疫情期间持续采取减灾策略作为对照。在感染率和发病率上,7天内0-病例的废除阈值与持续减灾策略相当,但在中度或严重大流行中需要减少6%到32%天数的减灾策略。如果再次出现病例,减灾策略将在预先确定的10个病例后重新启用,以阻止再次流行。当社区高度服从并与严格的减灾阈值联合使用时,减灾策略最有效。减少了执行控制流感大流行策略的需要,而发病率没有增加。关于废除社区在流感大流行期间实行的减灾策略@victoria j.Davey@Robert j.Glass@修文琼$福建省疾病预防控制中心@张拥军$福建省疾病预防控制中心

关键词：流感大流行减灾策略

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Grain refinement in low SFE and particle-containing nickel aluminium bronze during severe plastic deformation at elevated temperatures

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j.urnal of Materials Science & Technology 2021年第23期82卷 57-68页

作者： C.j.Barr K.Xia Department of Mechanical Engineering University of MelbourneVictoria3010Australia DMTC Ltd. 24 Wakefield St.HawthornVIC3122Australia

The influence of particle size and morphology on grain refinement in low stacking fault energy(SFE)alloys was studied by comparing the grain structures in single-and multi-phase Al-bronze(AB)alloys following equal channel angular pressing(ECAP)between 350 and 500℃.In particular,nickel aluminium bronze(NAB)was chosen as it contained both coarse and fine rounded particles,as well as a lamellar phase which evolved during *** refinement in the single-phase alloy was achieved through dynamic recrystallisation initiated at deformed twin *** contrast,different mechanisms were observed in the particle-containing *** around the coarseκⅡparticles(~5μm)was promoted through particle stimulated nucleation(PSN),whereas recrystallisation in the region of the fineκⅣ(~0.4μm)was delayed due to the activation of secondary *** refinement in areas of the lamellarκⅢshowed significant variation,depending on the lamellar orientation relative to the shear plane of *** the lamellae deformed,numerous high angle grain boundaries were generated between fragments and served as nucleation sites for recrystallisation,while PSN occurred around spheroidised *** spreading of theκⅢparticles by ECAP then enhanced the total area of recrystallised grains.

关键词： Equal channel angular pressing Copper alloys Grain refinement Stacking fault energy Severe plastic deformation

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临床医疗中利益冲突的管理:一项美国医学院校中相关政策的全国性调查

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中国医学人文评论 2014年 61-70页

作者： Susan Chimonas Lisa Patterson victoria H.Raveis David j.Rothman 胡林英美国哥伦比亚大学医学职业研究所纽约州立大学牙科学院

一、概况在过去的十年中,医学界的研究和媒体对临床中的利益冲突的关注日益增多。之前,人们主要关注的还是临床试验中的利益冲突问题[1-9]。而现在,我们开始关注利益冲突对医学临床的影响,这种新的兴趣反映了某些进展:首先,在20世纪90...

一、概况在过去的十年中,医学界的研究和媒体对临床中的利益冲突的关注日益增多。之前,人们主要关注的还是临床试验中的利益冲突问题[1-9]。而现在,我们开始关注利益冲突对医学临床的影响,这种新的兴趣反映了某些进展:首先,在20世纪90年代初,一系列研究表明,医药公司送给医生的礼品和酬金已经在深刻地影响着他们的信仰和行为[10,12,15-18]。其次,媒体无情地揭露医药公司和医生之间的紧密纽带是如何不正当地影响到了患者治疗[11,12,14,19]。再次,一系列备受关

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健康管理组织与制药产业:一项关于信息披露的分析

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中国医学人文评论 2014年 71-81页

作者： Sheila M.Rothman victoria H.Raveis Anne Friedman David j.Rothman 唐健美国哥伦比亚大学医学职业研究所

在对美国卫生政策最有影响力并最受公众信任的利益相关者中,各种健康管理组织(Health Advocacy Organization,HAO)是其中重要成员。他们致力于相关政策的制定,包括提高政府对医学研究的支持力度以及增强卫生保健服务的实效性。此外,HAO...

在对美国卫生政策最有影响力并最受公众信任的利益相关者中,各种健康管理组织(Health Advocacy Organization,HAO)是其中重要成员。他们致力于相关政策的制定,包括提高政府对医学研究的支持力度以及增强卫生保健服务的实效性。此外,HAO也为其成员谋求不受限地获得与他们健康状况匹配的药品与诊断工具。这些组织的立场同制药与医疗器械公司的市场营销目的密切相关,因为他们的立场有助于推动医疗产品的销售。虽然HAO与制药产业存在共同的

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Predicting Levels of Crude Protein, Digestibility, Lignin and Cellulose in Temperate Pastures Using Hyperspectral Image Data

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American j.urnal of Plant Sciences 2014年第7期5卷 997-1019页

作者： Susanne Thulin Michael j. Hill Alex Held Simon j.nes Peter Woodgate AusCover CSIRO Marine and Atmospheric Research Canberra Australia Cooperative Research Centre for Spatial Information Carlton Australia Department of Earth System Science and Policy University of North Dakota Grand Forks USA Department of Geospatial Sciences RMIT Univer-sity Melbourne Australia Department of Geospatial Sciences RMIT University Melbourne Australia Brockmann-Geomatics Sweden AB Kista Sweden

Hyperspectral sensors provide the potential for direct estimation of pasture feed quality attributes. However, remote sensing retrieval of digestibility and fibre (lignin and cellulose) content of vegetation has proven to be challenging since tissue optical properties may not be propagated to the canopy level in mixed cover types. In this study, partial least squares regression on spectra from HyMap and Hyperion imagery were used to construct predictive models for estimation of crude protein, digestibility, lignin and cellulose concentration in temperate pastures. HyMap and Hyperion imagery and field spectra were collected over four pasture sites in southern victoria, Australia. Co-incident field samples were analyzed with wet chemistry methods for crude protein, lignin and cellulose concentration, and digestibility was calculated from fiber determinations. Spectral data were subset based on sites and time of year of collection. Reflectance spectra were extracted from the hyperspectral imagery and collated for analysis. Six different transformations including derivatives and continuum removal were applied to the spectra to enhance absorption features sensitive to the quality attributes. The transformed reflectance spectra were then subj.cted to partial least squares regression, with full cross-validation “leave-one-out” technique, against the quality attributes to assess effects of the spectral transformations and post-atmospheric smoothing techniques to construct predictive models. Model performance between spectrometers, subsets and attributes were assessed using a coefficient of variation (CV), —the interquantile (IQ) range of the attribute values divided by the root mean square error of prediction (RMSEP) from the models. The predictive models with the highest CVs were obtained for digestibility for all spectra types, with HyMap the highest. However, models with slightly lower CVs were obtained for crude protein, lignin and cellulose. The spectral regions for di

关键词： Pasture Quality Crude Protein Digestibility Lignin Cellulose Hyperspectral Remote Sensing Partial-Least Squares Regression

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