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Comparing High-resistance Grounding Method with Resonance Grounding Method for Large Generators
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作者 Yao Huannian Cao Meiyue(Xiamen Electric Power Administration) 《Electricity》 1997年第3期22-25,共4页
For large generators, the problem of high-resistance grounding method and the advantages of resonance, grounding method are discussed in detail, and an overall comparison is given in this paper. It is recommended that... For large generators, the problem of high-resistance grounding method and the advantages of resonance, grounding method are discussed in detail, and an overall comparison is given in this paper. It is recommended that the latter should be adopted so as to increase the operation reliability of large generators and power systems. 展开更多
关键词 HIGH comparing High-resistance Grounding method with Resonance Grounding method for Large Generators
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A comparatives study of numerical methods in groundwater flow problem
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《Global Geology》 1998年第1期79-79,共1页
关键词 FLOW A comparatives study of numerical methods in groundwater flow problem
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我国省域公共卫生服务与经济耦合协调及提升路径 被引量:3
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作者 薛梓晨 罗盛 +5 位作者 秘玉清 李敏 高杰 陈彤 刘玉琢 李伟 《中国卫生资源》 CSCD 北大核心 2023年第2期157-162,共6页
目的探究我国各省域公共卫生服务与经济协调发展的现状及其影响因素,为地区实现高效、均衡发展提供建议。方法运用熵权法、耦合协调度、模糊集定性比较分析等方法评价我国各省域公共卫生服务与经济发展协调关系,借助fsQCA 3.0软件探究... 目的探究我国各省域公共卫生服务与经济协调发展的现状及其影响因素,为地区实现高效、均衡发展提供建议。方法运用熵权法、耦合协调度、模糊集定性比较分析等方法评价我国各省域公共卫生服务与经济发展协调关系,借助fsQCA 3.0软件探究二者协调关系的影响因素与驱动路径。结果2020年我国各省域公共卫生服务与经济发展耦合协调度属于良好协调等级以上的地区较少,大部分地区处于濒临失调状态。条件变量的必要性检验一致性均≤0.9,单一条件变量对地方公共卫生服务与经济协调发展驱动能力有限,存在多条件变量构成复杂驱动路径。组态分析共得出8种组态结果,共归纳为3种组态路径,其中组态1与组态2属于地方高经济水平主导型驱动路径,组态3、组态4、组态5和组态8属于公共卫生服务与地方经济融合型驱动路径,组态6与组态7属于公共卫生服务主导型驱动路径。结论我国公共卫生服务与经济发展协调性整体不高,每万人口公共卫生机构数、每万人口公共卫生技术人员数以及人均国内生产总值等是影响地方公共卫生服务与经济协调发展的核心因素,不同条件变量组合可促进地方公共卫生服务与经济协调发展。低协调地区可根据本地区实际情况,参考高协调路径,实现公共卫生服务与经济协调发展。 展开更多
关键词 公共卫生服务public health service 耦合水平coupling level 协调水平coordination level 模糊集定性比较分析法fuzzy set/qualitative comparative analysis fsQCA method 路径path
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Fault injection system for automatic testing system 被引量:1
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作者 王胜文 洪炳熔 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期321-324,共4页
Considering the deficiency of the means for confirming the attribution of fault redundancy in the re-search of Automatic Testing System(ATS) , a fault-injection system has been proposed to study fault redundancyof aut... Considering the deficiency of the means for confirming the attribution of fault redundancy in the re-search of Automatic Testing System(ATS) , a fault-injection system has been proposed to study fault redundancyof automatic testing system through compurison. By means of a fault-imbeded environmental simulation, thefaults injected at the input level of the software are under test. These faults may induce inherent failure mode,thus bringing about unexpected output, and the anticipated goal of the test is attained. The fault injection con-sists of voltage signal generator, current signal generator and rear drive circuit which are specially developed,and the ATS can work regularly by means of software simulation. The experimental results indicate that the faultinjection system can find the deficiency of the automatic testing software, and identify the preference of fault re-dundancy. On the other hand, some soft deficiency never exposed before can be identified by analyzing the tes-ting results. 展开更多
关键词 Fault injection comparing method rear drive ATS
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Evaluation of Nuclear Electromagnetic Pulse (NEMP) Vulnerability on Cots Electronic Equipments 被引量:1
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作者 Laurent Labarbe 《Journal of Physical Science and Application》 2013年第5期341-344,共4页
This study deals with a new evaluation method of nuclear electromagnetic pulse (NEMP) vulnerability on cots electronic equipments. The method consists in comparing electromagnetic compatibility (EMC) test severiti... This study deals with a new evaluation method of nuclear electromagnetic pulse (NEMP) vulnerability on cots electronic equipments. The method consists in comparing electromagnetic compatibility (EMC) test severities to NEMP conducted stresses. The comparison uses five characteristic criteria of the induced stresses, calculated with an analytic method. The process is based on a software named "SUSIE" (in French: SUSceptibilite a I'IEMN "Impulsion ElectroMagnttique d'origine Nucl6aire Haute Altitude"). Today, only conducted stresses are analyzed. An evolution is planned in 2013 to determine the equivalent vulnerability of radiated stresses and to validate the software. 展开更多
关键词 VULNERABILITY electromagnetic compatibility (EMC) test comparative method.
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A feasible method for comparing the power dependent photostability of fluorescent proteins 被引量:1
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作者 刘俊 储军 +4 位作者 朱宏宇 徐玲玲 张智红 曾绍群 黄振立 《Chinese Optics Letters》 SCIE EI CAS CSCD 2008年第12期941-943,共3页
A feasible method of combining the concept of fluorescence half-life and the power dependent photo- bleaching rate for characterizing the practical photostability of fluorescent proteins (FPs) was introduced. Furthe... A feasible method of combining the concept of fluorescence half-life and the power dependent photo- bleaching rate for characterizing the practical photostability of fluorescent proteins (FPs) was introduced. Furthermore, by using a fluorescent photostability standard, a relative comparison of the photostabilty of FPs from different research groups was proposed, which would be of great benefit for developing novel FPs with optimized emission wavelength, better brightness, and improved photostability. We used rho- damine B as an example to verify this method and evaluate the practical photostability of a far-red FP, mKate-S158C. Experimental results indicated good potential of this method for further study. 展开更多
关键词 A feasible method for comparing the power dependent photostability of fluorescent proteins
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Variation in Onko Dialect of Yoruba
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作者 Gbenga Fakuade Lawal Tope Aminat Adewale Rafiu 《宏观语言学》 2020年第2期64-82,共19页
This paper examined variation in Onko dialect using the family tree model and the corresponding comparative method as the theoretical tool. A wordlist of basic items and a designed frame technique were used to gather ... This paper examined variation in Onko dialect using the family tree model and the corresponding comparative method as the theoretical tool. A wordlist of basic items and a designed frame technique were used to gather data for this study. The data were presented in tables and the analyses were done through descriptive statistics. The data were analyzed to determine variation at the phonological, syntactic and lexical levels. The study revealed differences between Standard Yoruba and Onko dialect as well as the variation therein. Two basic factors discovered to be responsible for variations in Onko are geography(distribution of Onko communities) and language contact. The paper established that Onko exhibits variations, which are however not significant enough to disrupt mutual intelligibility among the speakers, and thus all the varieties remain a single dialect. 展开更多
关键词 VARIATION Onko dialect Yoruba family tree model comparative method TRIANGULATION
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Study on risk assessment and factors ranking of the LTE-M communication system
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作者 Xiaochun Wu Yu Gao Weichao Zheng 《Transportation Safety and Environment》 EI 2023年第4期45-57,共13页
To assess the operational safety risk of long-term evolution for the metro(LTE-M)communication system more accurately,the guide maintenance strategy,the improved evidence theory and the multi-attribute ideal reality c... To assess the operational safety risk of long-term evolution for the metro(LTE-M)communication system more accurately,the guide maintenance strategy,the improved evidence theory and the multi-attribute ideal reality comparative analysis(MAIRCA)approaches are proposed.According to the features of LTE-M system,the risk evaluation system is established.The enhanced structural entropy weight method is used to obtain the weight.Furthermore,it is combined with nine-element fuzzy mathematics to transform the degree of membership,modifying the conflict and fusion rules to solve the confidence degree clashed problem of evidence theory.Then,the system risk grade assessment result is obtained.For the purpose of forming the ranking of indicator importance,the MAIRCA is introduced and the ranking is three-dimensional.The operational state of the metro line is used as the data source in various ways the obtained risk grade increased by 7.12%.It is verified that MAIRCA can be applied to the field of urban rail transit because it has based on the test and calculation.The results show that the method is effective;compared with others,the confidence degree of excellent stability and the ranking result of risk factors is reasonable.The influencing indicator with the highest importance is the'equipment failure rate". 展开更多
关键词 long-term evolution for the metro(LTE-M)system operational safety risk assessment improved evidence theory multi-attribute ideal reality comparative analysis(MAIRCA)method
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Using the BirdTree.org website to obtain robust phylogenies for avian comparative studies: A primer 被引量:3
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作者 Diego RUBOLINI Andras LIKER +2 位作者 Laszlo Z. GARAMSZEGI Anders P. MOLLEIR Nicola SAINO 《Current Zoology》 SCIE CAS CSCD 2015年第6期959-965,共7页
Comparative studies of trait evolution require accounting for the shared evolutionary history. This is done by includ- ing phylogenetic hypotheses into statistical analyses of species' traits, for which birds often s... Comparative studies of trait evolution require accounting for the shared evolutionary history. This is done by includ- ing phylogenetic hypotheses into statistical analyses of species' traits, for which birds often serve as excellent models. The online publication of the most complete molecular phylogeny of extant bird species (www.birdtree.org, BirdTree hereafter) now allows evolutionary biologists to rapidly obtain sets of equally plausible phylogenetic trees for any set of species to be incorporated as a phylogenetic hypothesis in comparative analyses. We discuss methods to use BirdTree tree sets for comparative studies, either by building a consensus tree that can be incorporated into standard comparative analyses, or by using tree sets to account for the ef- fect of phylogenetie uncertainty. Methods accounting for phylogenetic uncertainty should be preferred whenever possible because they should provide more reliable parameter estimates and realistic confidence intervals around them. Based on a real compara- tive dataset, we ran simulations to investigate the effect of variation in the size of the random tree sets downloaded from BirdTree on the variability of parameter estimates from a bivariate relationship between mass-specific productivity and body mass. Irre- spective of the method of analysis, using at least 1,000 trees allows obtaining parameter estimates with very small (〈 0.15%) co- efficients of variation. We argue that BirdTree, due to the ease of use and the major advantages over previous 'traditional' meth- ods to obtain phylogenetic hypotheses of bird species (e.g. supertrees or manual coding of published phylogenies), will become the standard reference in avian comparative studies for years to come. 展开更多
关键词 Birds BirdTree Comparative method PGLM PGLS Phylogenetic uncertainty
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A comparison of fecal sampling and direct feeding observations for quantifying the diet of a frugivorous primate 被引量:2
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作者 Jaya K.MATTHEWS Amanda R.IDLEY +1 位作者 Beth A.KApuN Cyril C.GRUETER 《Current Zoology》 SCIE CAS CSCD 2020年第4期333-343,共11页
Both observational and indirect evidence are widely used to determine the diets of wild animals.Direct observations are often assumed to provide the most comprehensive reflection of diet,but many wild animals are logi... Both observational and indirect evidence are widely used to determine the diets of wild animals.Direct observations are often assumed to provide the most comprehensive reflection of diet,but many wild animals are logistically challenging to observe.Despite the regular use of observa-tional and indirect methods for inferring diet in wild animals,they have rarely been compared in detail for the same study population.Over 12 months this study assessed the congruence of methods in estimating the diet of a montane community of eastern chimpanzees Pan troglodytes schweinfurthii in Nyungwe National Park,Rwanda using observational scan samples and macro-scopic fecal inspection.The assessment of the number of food species consumed each month was comparable between methods,but the estimation of the composition of items in the diet differed significantly.Most notably,the fecal samples significantly underestimated the consumption of flowers,and certain fruit species,which based on direct behavioral observations were seasonally consumed at very high rates.Conversely,direct observations underestimated the consumption of leaves and pith in comparison to results present in the fecal samples.These results suggest that combining methods where possible is most useful for accurate monitoring of dietary trends,particularly for species that experience significant seasonal shifts in their diet. 展开更多
关键词 CHIMPANZEE comparative methods dietary analysis SEASONALITY
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The evolution of multi-component visual signals in darters (genus Etheostoma) 被引量:1
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作者 Jennifer M. GUMM Tamra C. MENDELSON 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第2期125-139,共15页
As complex traits evolve, each component of the trait may be under different selection pressures and could respond independently to distinct evolutionary forces. We used comparative methods to examine patterns of evol... As complex traits evolve, each component of the trait may be under different selection pressures and could respond independently to distinct evolutionary forces. We used comparative methods to examine patterns of evolution in multiple components of a complex courtship signal in darters, specifically addressing the question of how nuptial coloration evolves across different areas of the body. Using spectral reflectance, we defined 4 broad color classes present on the body and fins of 17 species of freshwater fishes (genus Etheostoma) and quantified differences in hue within each color class. Ancestral state reconstruction suggests that most color traits were expressed in the most recent common ancestor of sampled species and that differences among species are mostly due to losses in coloration. The evolutionary lability of coloration varied across body regions; we found sig- nificant phylogenetic signal for orange color on the body but not for most colors on fins. Finally, patterns of color evolution and hue Of the colors were correlated among the two dorsal fins and between the anterior dorsal and anal fins, but not between any of the fins and the body. The observed patterns support the hypothesis that different components of complex signals may be subject to distinct evolutionary pressures, and suggests that the combination of behavioral displays and morphology in communication may have a strong influence on patterns of signal evolution . 展开更多
关键词 Comparative method ETHEOSTOMA Independent evolution Nuptial coloration
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Vivid birds do not initiate flight sooner despite their potential conspicuousness 被引量:1
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作者 Nicholai M. HENSLEY Jonathan P. DRURY +1 位作者 Theodore GARLAND, Jr. Daniel T. BLUMSTEIN 《Current Zoology》 SCIE CAS CSCD 2015年第4期773-780,共8页
The distance from an approaching threat at which animals initiate flight - flight-initiation distance (FID) -- is a sensitive metric of variation in risk, but the effects on FID associated with the risk of possessin... The distance from an approaching threat at which animals initiate flight - flight-initiation distance (FID) -- is a sensitive metric of variation in risk, but the effects on FID associated with the risk of possessing highly detectable external coloration are unknown. We tested whether variation in the degree of plumage vividness in birds explained variation in flight-initiation distance. After controlling for body mass, the distance at which the experimental approach began, and phylogenetic relatedness, plumage vividness was not a predictor of FID. Contrary to the expectation that vividness affects risk, and therefore risk assess- ment, these results suggest that birds do not compensate for greater visual conspicuousness by fleeing sooner from approaching threats [Current Zoology 61 (4): 773-780, 2015]. 展开更多
关键词 Antipredator behavior Body size COLORATION Comparative method CONSPICUOUSNESS Flight Initiation Distance
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A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis 被引量:1
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作者 Alex D.Potash Daniel U.Greene +3 位作者 Gabrielle A.Foursa Verity L.Mathis L.Mike Conner Robert A.McCleery 《Current Zoology》 SCIE CAS CSCD 2020年第6期601-606,共6页
An animal's pelage,feather,or skin color can serve a variety of functions,so it is important to have multiple standardized methods for measuring color.One of the most common and reliable methods for measuring anim... An animal's pelage,feather,or skin color can serve a variety of functions,so it is important to have multiple standardized methods for measuring color.One of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of animals.New tech no logy in the form of a commercially available handheld digital color sensor could provide an alter native to photography-based animal color measurements.To determine whether a digital color sensor could be used to measure animal coloration,we tested the ability of a digital color sensor to measure coloration of mammalian,avian,and lepidopteran museums specimens.We compared results from the sensor to measurements taken using traditional photography methods.Our study yielded significant differences between photography-based and digital color sensor measurements of brightness(light to dark)and colors along the green to red spectrum.There was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow spectrum.The average difference in recorded color(AE)by the 2 methods was above the threshold at which humans can perceive a difference.There were sign讦icant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring tool.However,the sensor's small aperture and narrow light spectrum range designed for human-vision limit its value for ecological research.We discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field. 展开更多
关键词 animal coloration color measurement comparative method digital photography museum specimens Nix color sensor
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Macro-evolutionary patterns of East Asian opsariichthyin-xenocyprinin-cultrin fishes related to the formation of river and river-lake environments under monsoon climate 被引量:1
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作者 Peilin Cheng Dan Yu +3 位作者 Qiongying Tang Jinquan Yang Yiyu Chen Huanzhang Liu 《Water Biology and Security》 2022年第2期81-95,共15页
Although the East Asian monsoon is believed to be an important driver for the origin and evolution of the biotas in this region,the association has rarely been rigorously tested.Here,using phylogenetic comparative met... Although the East Asian monsoon is believed to be an important driver for the origin and evolution of the biotas in this region,the association has rarely been rigorously tested.Here,using phylogenetic comparative methods and analyses of key innovations of adaptive traits,we investigated evolutionary patterns of the East Asian cyprinid opsariichthyin-xenocyprinin-cultrin clade;the dominant species in lakes and rivers,which are the typical productions of monsoon climate.Our molecular phylogenetic analyses revealed the relationships as(Opsariichthystribe t(((Oxygaster-tribe t Aphyocypris-tribe)t Metzia-tribe)t(Paralaubuca-tribe t(Squaliobarbus-tribe t(Hypophthalmichthys-tribe t(xenocyprinins t cultrins)))))).Based on Bayesian relaxed-clock methods,we found that origins of the Squaliobarbus-and Hypophthalmichthys-tribes bearing the key adaptation of riverine spawning with drifting eggs occurred 22.5 and 21.1 Mya,respectively.These times are consistent with the Early Miocene origin of major rivers(e.g.,Yangtze River)and the appearance of the East Asian monsoon climate.Diversification of the cultrins,characterized by spawning of adhesive eggs as well as swimming and feeding in lentic waters,were estimated to have evolved 16.6 to 0.2 Mya.This period covers three phases of enhancement of the East Asian monsoon from the Middle Miocene to the Pliocene(around 15–13,10–7,and 3.5 Mya).The habitats of these cultrins and their evolution also suggest the appearance and development of a lake-river environment during those periods.Therefore,our results suggest close relationships between the evolution of these fishes and geological events in East Asia.Further,they provide knowledge that may help facilitate future conservation strategies such as the maintenance of high river flows during dam construction and operation. 展开更多
关键词 East Asia CYPRINIDAE Phylogenetic comparative methods Yangtze river River-lake environments
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Functional diversity of small-mammal postcrania is linked to both substrate preference and body size
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作者 Lucas N.Weaver David M.Grossnickle 《Current Zoology》 SCIE CAS CSCD 2020年第5期539-553,共15页
Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ecomorphotypes.However,the effects of these selective pressures vary across taxa,especially because m... Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ecomorphotypes.However,the effects of these selective pressures vary across taxa,especially because morphology is also influenced by factors such as phylogeny,body size,and functional trade-offs.In this study,we examine how these factors impact functional diversification in mammals.It has been proposed that trait partitioning among mammalian ecomorphotypes is less pronoun ced at small body sizes due to biomecha nical,energetic,and environ mental factors that favor a"generalist"body plan,whereas larger taxa exhibit more substantial functional adaptations.We title this the Diverge nee Hypothesis(DH)because it predicts greater morphological divergence among ecomorphotypes at larger body sizes.We test DH by using phylogenetic comparative methods to examine the postcranial skeletons of 129 species of taxonomically diverse,small-tomedium-sized(<15 kg)mammals,which we categorize as either"tree-dwellers"or"ground-dwellers."In some analyses,the morphologies of ground-dwellers and tree-dwellers suggest greater between-group differentiation at larger sizes,providing some evidence for DH.However,this trend is n either particularly strong nor supported by all an alyses.In stead,a more pronoun ced patter n emerges that is distinct from the predictions of DH:within-group phenotypic disparity increases with body size in both ground-dwellers and tree-dwellers,driven by morphological outliers among"medium'-sized mammals.Thus,evolutionary increases in body size are more closely linked to increases in within-locomotor-group disparity tha n to in creases in betwee n-group disparity.We discuss biomechanical and ecological factors that may drive these evolutionary patter ns,and we emphasize the significant evolutionary influences of ecology and body size on phenotypic diversity. 展开更多
关键词 adaptive landscapes ECOMORPHOLOGY morphometries phenotypic diversity phylogenetic comparative methods trait partitioning
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Sexual dimorphism in cranial shape and size in geomyoid rodents:multivariate and evolutionary perspectives
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作者 Jonathan J M Calede Andrew Brown 《Current Zoology》 SCIE CAS CSCD 2022年第4期469-487,共19页
Geomyoid rodents provide a great study system for the analysis of sexual dimorphism.They are polygynic and many inhabit harsh arid environments thought to promote sexual dimorphism.In fact,there has been extensive wor... Geomyoid rodents provide a great study system for the analysis of sexual dimorphism.They are polygynic and many inhabit harsh arid environments thought to promote sexual dimorphism.In fact,there has been extensive work published on the sexual size dimorphism of individual populations and species within this rodent clade.However,little work has been undertaken to assess the evolutionary patterns and processes associated with this sexual dimorphism.We use multivariate analyses of cranial measurements in a phylogenetic framework to determine the distribution of size and shape dimorphism among geomyoids and test for Rensch’s rule.Our results suggest that sexual dimorphism is more common in geomyids than heteromyids,but it is not in fact universal.There is evidence for variation in sexual dimorphism across populations.Additionally,in many taxa,geographic variation appears to overwhelm existing sexual dimorphism.We find support for the repeated independent evolution of shape and size dimorphism across geomyoid taxa,but we do not find support for an association between size and shape dimorphism.There is no evidence for Rensch’s rule in geomyoids,whether at the superfamily or family level.Together,our findings suggest that there is no single explanation for the evolution of sexual dimorphism in geomyoids and that,instead,it is the product of numerous evolutionary events.Future studies incorporating phylogenetic relationships will be necessary to paint a more complete picture of the evolution of sexual dimorphism in geomyoids. 展开更多
关键词 Geomyidae HETEROMYIDAE phylogenetic comparative methods MORPHOMETRICS Rensch’s rule
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Do key innovations unlock diversification?A case-study on the morphological and ecological impact of pharyngognathy in acanthomorph fishes
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作者 Olivier Larouche Jennifer R.Hodge +6 位作者 Laura R.V.Alencar Benjamin Camper Danielle S.Adams Katerina Zapfe Sarah T.Friedman Peter C.Wainwright Samantha A.Price 《Current Zoology》 SCIE CAS CSCD 2020年第5期575-588,共14页
Key inn ovations may allow lin eages access to new resources and facilitate the invasi on of new adaptive zon es,potentially influencing diversificati on patter ns.Many studies have focused on the impact of key inno v... Key inn ovations may allow lin eages access to new resources and facilitate the invasi on of new adaptive zon es,potentially influencing diversificati on patter ns.Many studies have focused on the impact of key inno vations on speciation rates,but far less is known about how they influe nee phe notypic rates and patterns of ecomorphological diversification.We use the repeated evolution of pharyngognathy within acanthomorph fishes,a commonly cited key innovation,as a case study to explore the predicti ons of key inn ovation theory.Specifically,we in vestigate whether transiti ons to phary ngognathy led to shifts in the rate of phenotypic evolution,as well as shifts and/or expansion in the occupation of morphological and dietary space,using a dataset of 8 morphological traits measured across 3,853 species of Acanthomorpha.Analyzing the 6 evolutionarily independent pharyngognathous clades together,we found no evidence to support pharyngognathy as a key innovation;however,comparisons between individual pharyngognathous lineages and their sister clades did reveal some consistent patterns.In morphospace,most pharyngognathous clades cluster in areas that correspond to deeper-bodied morphologies relative to their sister clades,whereas occupying greater areas in dietary space that reflects a more diversified diet Additi on ally,both Cichlidae and Labridae exhibited higher univariate rates of phenotypic evolution compared with their closest relatives.However,few of these results were exceptional relative to our null models.Our results suggest that transitions to pharyngognathy may only be advantageous when combined with additional ecological or intrinsic factors,illustrating the importance of account!ng for lineage-specific effects when testing key innovation hypotheses.Moreover,the challenges we experienced formulating informative comparisons,despite the ideal evolutionary scenario of multiple independent evolutionary origins of pharyngognathous clades,illustrates the complexities involved in quantifying the impact of key innovations.Given the issues of lineage specific effects and rate heterogeneity at macroevolutionary scales we observed,we suggest a reassessment of the expected impacts of key innovations may be warranted. 展开更多
关键词 Acanthomorpha comparative methods ecomorphological diversification evolutionary innovations phenotypic rates
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Missing in total OH reactivity of VOCs from gasoline evaporation
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作者 Ying Wu Yu-Dong Yang +1 位作者 Min Shao Si-Hua Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第10期1246-1248,共3页
Gasoline evaporation is an important anthropogenic source of atmospheric volatile organic compounds(VOCs). Total OH reactivity for gasoline vapor was measured from 4 kinds of gasoline for the first time by comparati... Gasoline evaporation is an important anthropogenic source of atmospheric volatile organic compounds(VOCs). Total OH reactivity for gasoline vapor was measured from 4 kinds of gasoline for the first time by comparative reactivity method(CRM) using proton transfer reaction mass spectrometer(PTR-MS).Compositions of 56 PAMS(photochemical assessment monitoring station) nonmethane hydrocarbons(NMHCs) were measured for both liquid and headspace of gasoline. We found high abundance of alkenes and aromatics in gasoline. The calculated OH reactivity derived from quantified NMHCs speciation accounted for only 57 ? 4% of total reactivity obtained from CRM method. N-Alkenes, only 6 wt% in liquid gasoline, contributed to 70% of calculated reactivity. We assume that the undetected branched alkenes are the possible reason for the missing reactivity. We suggest that the priority of gasoline quality improvement is to reduce alkenes content in gasoline in term of reactivity-based control. 展开更多
关键词 Volatile organic compounds(VOCs) Comparative reactivity method(CRM) Missing OH reactivity Gasoline evaporation
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THE FORENSIC CHALLENGE
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作者 Paul Roberts 《Frontiers of Law in China-Selected Publications from Chinese Universities》 2018年第1期43-66,共24页
This article investigates what might be characterised as "the forensic challenge" for criminal adjudication and clarifies its nature and scope. The "challenge" identified is complex, dynamic and multifaceted, enco... This article investigates what might be characterised as "the forensic challenge" for criminal adjudication and clarifies its nature and scope. The "challenge" identified is complex, dynamic and multifaceted, encompassing a variety of issues and debates concerning the ways in which forensic science evidence is validated, generated, presented, tested, evaluated and utilised in criminal proceedings. Common law evidentiary principles governing the admissibility of scientific evidence and expert witness testimony are reviewed and the underlying assumptions and potential weaknesses of adversarial trial procedure are critically considered. The discussion is pitched at the generic level of recurring intellectual puzzles, institutional design, regulatory frameworks, procedural structures and processes, macro-policy choices and methodological prescriptions, with the intention of making it relevant to an international audience. Aspects of the procedural law and adjudicative practice of England and Wales, and the regulatory context of UK forensic science, are offered as concrete illustrations with the potential for illuminating comparative extrapolation to other legal systems. In conclusion, the article draws out specific implications for Chinese scholarship, law reform and policymaking in relation to scientific and other expert evidence, and advances a bold suggestion for entertaining an unconventionally expansive conception of "forensic science" and, correspondingly, of the challenges it presents. 展开更多
关键词 forensic science expert evidence criminal procedure comparative legal method criminal justice reform
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