检索结果-南通市图书馆

Disturbance cue communication is shaped by emitter diet and receiver background risk in Trinidadian guppies

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2022年第4期68卷 433-440页

作者： Jack A Goldman adam l crane laurence e A Feyten emily Collins grant e.brown Department of Biology Concordia University7141 Sherbrooke Street WestMontrealQCCanada H4B 1R6

In animal communication systems,individuals that detect a cue(i.e.,“receivers”)are often influenced by characteristics of the cue *** instance,in many species,receivers avoid chemical cues that are released by emitters experiencing *** chemical“disturbance cues”appear to benefit receivers by warning them about nearby danger,such as a predator’s *** the active ingredients in disturbance cues have been largely unexplored,by-products of metabolized protein are thought to play a role for some *** so,the content(quality)and volume(quantity)of the emitter’s diet should affect their disturbance cues,thus altering how receivers perceive the cues and *** Poecilia reticulata are a species known to discriminate among disturbance cues from different types of donors,but dietary variation has yet to be *** this study,we found evidence that diet quality and quantity can affect disturbance cues released by guppy emitters(i.e.,experimental“donors”).Receivers discriminated between donor cue treatments,responding more strongly to cues from donors fed a protein-rich bloodworm diet(experiment 1),as well as an overall larger diet(experiment 2).We also found that receivers exposed to higher background risk were more sensitive to disturbance cue variation,with the strongest avoidance responses displayed by high-risk receivers toward disturbance cues from donors fed the high-quality ***,diet,and perhaps protein specifically,affects either the concentration or composition of disturbance cues released by *** variation may be important in information signaling in social species like the guppy.

关键词： alarm cues chemical cues diet quality diet quantity protein

Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(linum l.)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Oil Crop Science 2024年第2期9卷 121-130页

作者： Kenyon J. Nisbett Abida Alokozai Su Hyun elizabeth Ko G. adam Mott Jason C.l. browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of Cell&Systems Biology University of TorontoTorontoONCanada Centre for the Analysis of Genome evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(linum l.)subjected to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subjected to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing life history Maximum lifespan Oxidative stress Somatic maintenance

Wildfire severity alters soil microbial exoenzyme production and fungal abundances in the southern Appalachian Mountains

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2024年第5期34卷 865-878页

作者： Megan l.SCHIll Richard BAIRD Shawn P.brown Allison M.VeACH Department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University Department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian Mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky Mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY Işıl SANRI KARAPINAR Zehra N.KUTlU İsmail e.KIlIÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inİstanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On B(5,20)2-Groups

Algebra Colloquium 2024年第3期31卷 429-440页

作者： e.A.Alhassan Y.l.Tan Y.li School of Mathematical Sciences Jiangsu UniversityZhenjiangJiangsu 212013China Department of Mathematics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-element subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a complete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups small squaring property central extension GAP

When Fleeing Matters:Differences in escape Behaviours of Three Northeast Asian Anurans

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Herpetological Research 2024年第1期15卷 41-48页

作者： Yoonjung YI Zoljargal PUReVDORJ Irina MASlOVA Yikweon JANG Amaël BORZÉe laboratory of Animal Behaviour and Conservation College of Life SciencesNanjing Forestry UniversityNanjing 210037JiangsuChina Division of ecoScience and Department of life Sciences Ewha Womans UniversitySeoul 03760Republic of Korea Department of Biology School of MathematicsMongolian State University of EducationUlaanbaatar 210648Mongolia Department of Forest and environmental Resources Chungnam National UniversityDaejeon 34134Republic of Korea Federal Scientific Center of the east Asia Terrestrial Biodiversity Far Eastern Branch of Russian Academy of SciencesVladivostok 690022Russia

Prey species may have their own optimal escape strategy to balance predation risks and the energetic cost of *** species have an advantage when maintaining a short fleeing distance,while others may favour an earlier escape based on microhabitat,size,or body ***,we examined the escape behaviour of the three syntopic Northeast Asian anuran species:Mongolian toads(Strauchbufo raddei),Amur brown frogs(Rana amurensis),and Japanese treefrogs(Dryophytes japonicus)in Mongolia,Russia,China and DPR *** examined flight initiation distance(FID;the distance from a potential predator to the point when the individual starts to flee)and distance fled(DF;distance between flight initiation and flight termination points)of each species and the effects of microhabitat,sex,and body *** raddei and *** had a longer FID than ***,and *** also had a longer DF than *** trends remained similar when dividing FID and DF by a size proxy(snout-vent length)for all *** suggests that the treefrog *** used a strategy to stay immobile even when they were detected,and the toad *** reacted quicker and more sensitively to predators despite the presence of *** *** had a significantly longer FID than males suggesting that females are more sensitive to predation risk in this species,but body size was not significant for any of the three *** results indicate that the three sympatric species have different escaping strategies,likely related to differences in physiology and crypticity.

关键词： amphibian distance fled escape behaviour flight initiation distance predation

Older Adult Compendium of Physical Activities:energy costs of human activities in adults aged 60 and older

在线全文

学校读者我要写书评

暂无评论

Journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： erik A.Willis Stephen D.Herrmann Mary Hastert Chelsea l.Kracht Tiago V.Barreira John M.Schuna Jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.brown Barbara e.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MeT)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,embase,SPORTDiscus(eBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),ml/kg/min)during PA divided by 2.7 m l/kg/min(MeT_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MeT_(60+)values for older *** developed a website to present the OA Compendium MeT_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MeT_(60+)values for older adults for use in PA research and practice.

关键词： energy expenditure exercise MeT Older adults

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

在线全文

学校读者我要写书评

暂无评论

Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.M.Saporetti l.C.Oliveira e.Pereira Department of Computational and Applied Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of Computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'TOC content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning evolutionary algorithms Geology

Phanerozoic co-evolution of O2-CO2 and ocean habitability

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 18-21页

作者： Zunli lu Rosalind e.M.Rickaby Jonathan l.Payne Ashley N.Prow Department of earth & environmental Sciences Syracuse University Department of earth Sciences University of Oxford Department of earth and Planetary Sciences Stanford University

Atmospheric carbon dioxide and oxygen concentrations are partially linked via the geological cycle of organic carbon （Fig. 1A–C; e.g. CO2+H2O■CH2O+O2）. The history of these two biologically active components, controls on their concentrations, and implications for the complexity of the biosphere and habitability of earth have been hotly debated, but are generally considered independently.

关键词： CO2-CONCeNTRATING MeCHANISM OXYGeN eVOlUTION ANOXIA