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511.
《Anthrozo?s》2013,26(1):145-152
ABSTRACTThere is increasing interest among social and behavioral scientists in brief measures of attitudes and personality traits. Based on factor analysis and using an existing data set (n = 400 adults), we constructed a 5- and a 10-item version of the widely used animal attitude Scale (AAS). Both versions were highly correlated with the original 20-item AAS (rs > 0.95, p < 0.001), and both versions demonstrated acceptable reliability and validity. The AAS-5 and the AAS-10 have excellent psychometric properties and offer alternatives for researchers who need convenient and short measures of attitudes related to animal welfare. 相似文献
512.
Our ability to detect patterns of variation of communities depends on the spatial scale of observation. I examined the spatial variation of macroinvertebrate community structure: abundance, richness, evenness, percentage of Ephemeroptera, Plecoptera and Trichoptera (EPT), and taxonomic composition across a wide range of spatial scales in two mountain streams. In a nested design, three segments were selected within each basin, three riffles within each segment, three sections within each riffle, and three samples within each section. Significant variation of communities occurred mainly at sample and riffle scales, although different community characteristics may vary at different scales. Environmental factors were strongly related to communities, but these relationships depended on spatial scale in many cases, suggesting that the influence of the environment is ultimately regulated by the grain and extent of organisms. This study highlights the importance of multiscale studies to obtain a complete understanding of the spatial variation of macroinvertebrate communities and their relationship with the environment. 相似文献
513.
Paul Whalley 《Biological journal of the Linnean Society. Linnean Society of London》1986,28(3):253-271
The problems associated with the identification of lepidopterous fossils (Insecta) are discussed. The origins and evolution of scales in the Amphiesmenoptera (Lepidoptera + Trichoptera) is considered. An illustrated review of the 19 Mesozoic insects described as lepidopterous is given and their identity discussed. Ample evidence of diversity of Lepidoptera in the Cretaceous, evidence (two specimens) of their presence in the Jurassic and some evidence of their presence in the Triassic is given. 相似文献
514.
Roshan Mammen Regy Jacob Thompson Young C. Kim Jeetain Mittal 《Protein science : a publication of the Protein Society》2021,30(7):1371
We present improvements to the hydropathy scale (HPS) coarse‐grained (CG) model for simulating sequence‐specific behavior of intrinsically disordered proteins (IDPs), including their liquid–liquid phase separation (LLPS). The previous model based on an atomistic hydropathy scale by Kapcha and Rossky (KR scale) is not able to capture some well‐known LLPS trends such as reduced phase separation propensity upon mutations (R‐to‐K and Y‐to‐F). Here, we propose to use the Urry hydropathy scale instead, which was derived from the inverse temperature transitions in a model polypeptide with guest residues X. We introduce two free parameters to shift (Δ) and scale (µ) the overall interaction strengths for the new model (HPS‐Urry) and use the experimental radius of gyration for a diverse group of IDPs to find their optimal values. Interestingly, many possible (Δ, µ) combinations can be used for typical IDPs, but the phase behavior of a low‐complexity (LC) sequence FUS is only well described by one of these models, which highlights the need for a careful validation strategy based on multiple proteins. The CG HPS‐Urry model should enable accurate simulations of protein LLPS and provide a microscopically detailed view of molecular interactions. 相似文献
515.
516.
LI Chuan-hua ZHOU Min WANG Yu-tao ZHU Tong-bin SUN Hao YIN Huan-huan CAO Hong-juan HAN Hai-yan 《生态学杂志》1982,39(10):3265
517.
Human-caused genetic changes in two Atlanticsalmon (Salmo salar L.) stocks, from therivers Iijoki and Oulujoki in Finland, wereassessed by comparing the genetic parameters ofthese stocks before and after the hatcherybreeding of several successive generations,corresponding to 40 and 33 years since the wildstate. The changes were also compared withthose observed in a large wild salmon stock inthe River Teno during 56 years. In all, thevariation at seven microsatellite DNA loci wasexamined in 11 Atlantic salmon samplesoriginating from these three rivers. Theeffective population size, Ne, duringbreeding of the Iijoki broodstock and for theTeno salmon was also estimated by the temporalmethod based on allele frequency changes. Forthe Iijoki broodstock, the changes could betracked generation by generation from thefounding of the stock. Statisticallysignificant changes in allele frequencies werecommon in the hatchery stocks (F = 0.029, forIijoki), but not in the wild Teno stock, whichwas temporally very stable (F = 0.007). Allelicrichness decreased statistically significantly(24.8%) in the Oulujoki broodstock, from 62.1to 46.7 alleles at nine loci. On average, therewere 9.7 fewer alleles (15.7%) in thecontemporary broodstocks than in thecorresponding historical stocks. The meanheterozygosity was 6.6% lower in thecontemporary Oulujoki broodstock, but remainedunchanged in the Iijoki broodstock. Theestimated Ne for the Iijoki broodstock wasunder 80 for 4.5 generations from 1962 to 1995and for the wild Teno salmon over 900 for 56years from 1939 to 1995. 相似文献
518.
Different methodologies try to identify priority conservation areas (PCA) to improve habitat conservation and decrease human pressures over bird species at coarse-scale. Map of potential biodiversity (PB) can identify PCA (high PB values) at different scale levels by considering ecological requirements and distributions through potential habitat suitability (PHS) models. The aim was to elaborate a map of PB of bird species based on PHS models to spatially identify PCA in Santa Cruz, Argentina. Moreover, we want to analysis species’ ecology requirements, and evaluate PB values and spatially identify PCA through two scale levels. We computed 47 models using Environmental Niche Factor Analysis (ENFA) on Biomapper software. Each model was visualized and combined to get a unique map of PB. We analyzed ecological requirements by specialization and marginality and PHS maps. Moreover, considering natural environments (regional level) and forest types’ cover (forest landscape level), we evaluated PB values using ANOVAs and identified PCA under different human pressures, using human footprint (HPF) map. Bird species related to Nothofagus forests were most specialist and exhibited a narrower potential distribution than grassland species. At regional level, Magellanic grass steppes displayed the highest PB values, where most of the PCA had high HPF values. At forest landscape level, ecotone N. antarctica forests had the highest PB values, where PCA with low HFP values were outside current protected networking. We conclude that combining PHS models and the map of PB allowed us to improve bird distribution studies and to assist biodiversity conservation strategies under human pressures. 相似文献
519.
Felisa A. Smith S. Kathleen Lyons 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2011,366(1576):2364-2378
Macroecology was developed as a big picture statistical approach to the study of ecology and evolution. By focusing on broadly occurring patterns and processes operating at large spatial and temporal scales rather than on localized and/or fine-scaled details, macroecology aims to uncover general mechanisms operating at organism, population, and ecosystem levels of organization. Macroecological studies typically involve the statistical analysis of fundamental species-level traits, such as body size, area of geographical range, and average density and/or abundance. Here, we briefly review the history of macroecology and use the body size of mammals as a case study to highlight current developments in the field, including the increasing linkage with biogeography and other disciplines. Characterizing the factors underlying the spatial and temporal patterns of body size variation in mammals is a daunting task and moreover, one not readily amenable to traditional statistical analyses. Our results clearly illustrate remarkable regularities in the distribution and variation of mammalian body size across both geographical space and evolutionary time that are related to ecology and trophic dynamics and that would not be apparent without a broader perspective. 相似文献
520.
A clonal isolate of Chrysodidymus synuroideus Prowse was derived form a Sphagnum bog in northern Wisconsin and maintained in culture for over 3 years. Cultured colonies consisted almost exclusively of two cells attached at the posterior, each cell bearing two unequal flagella. Correlative light and electron microscopic observations revealed that colonies composed of smaller, ovate cells represented more recent products of cell division, while colonies of elongate cells were more mature. These results support previous taxonomic conclusions, based on light microscopic observations, of field-collected specimens and body scale ultrastructure, that Chrysodidymus is a valid genus, and that two species described by Prowse on the basis of cell size differences, should be merged. In addition, ultrastructural studies of cultured Chrysodidymus demonstrated that this genus is a member of the Synurophyceae on the basis of characters related to flagellar morphology, basal body arrangement, and cytoskeletal ultrastructure. Chrysodidymus synuroideus resembles Synura sphagnicola in body scale structure, the presence of distinctive linear or clavate scales on both flagella, a relatively loose scale case, and acidophilic habital, Unlike S. sphagnicola, Chrysodidymus has no Pyrennoids, Peripheral (rather than axial) plastids, and a single posterior storage vesicle (rather than two peripheral storage vesicles). 相似文献