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931.
Valentina Milana Paolo Franchini Luciana Sola Elisa Angiulli Anna Rita Rossi 《Marine Biology》2012,159(2):399-411
Atherina boyeri is a common inhabitant of the Mediterranean brackish and coastal waters. Several recent studies proposed the recognition
of three distinct forms/species (one lagoon/freshwater and two marine) within an A. boyeri complex. In this study, we used 10 newly available microsatellite loci to better define the genetic structure of the lagoon
form. A total of 428 fishes from 11 lagoons along the Italian and Albanian coasts and three Italian lakes were analyzed. A
pronounced genetic spatial structure was confirmed for all considered geographic scales (near, medium and broad). A restricted
gene flow was detected, suggesting reduced population connectivity. The comparison of present data and previous studies, based
on mtDNA and RAPD markers, allowed a preliminary identification of the roles of recent factors (gene flow, habitat discontinuity
and water currents) and past events (e.g., Pleistocene glaciations) in shaping the pattern of genetic differentiation. 相似文献
932.
Noa Pinter-Wollman Julia Hubler Jo-Anne Holley Nigel R. Franks Anna Dornhaus 《Behavioral ecology and sociobiology》2012,66(10):1407-1420
How social insect colonies behave results from the actions of their workers. Individual variation among workers in their response to various tasks is necessary for the division of labor within colonies. A worker may be active in only a subset of tasks (specialist), perform all tasks (elite), or exhibit no particular pattern of task activity (idiosyncratic). Here we examine how worker activity is distributed among and within tasks in ants of the genus Temnothorax. We found that workers exhibited elitism within a situation, i.e., in particular sets of tasks, such as those associated with emigrations, nest building, or foraging. However, there was weak specialization for working in a particular situation. A few workers exhibited elitism across all situations, i.e., high performance in all tasks in all situations. Within any particular task, the distribution of activity among workers was skewed, with few ants performing most of the work and most ants performing very little of the work. We further found that workers persisted in their task preference over days, with the same individuals performing most of the work day after day. Interestingly, colonies were robust to the removal of these highly active workers; they were replaced by other individuals that were previously less active. This replacement was not short-lived; when the removed individuals were returned to the colony, not all of them resumed their prior high activity levels, and not all the workers that replaced them reduced their activity. Thus, even though some workers specialize in tasks within a particular situation and are persistent in performing them, task allocation in a colony is plastic and colonies can withstand removal of highly active individuals. 相似文献
933.
Matina?C.?Donaldson-MatasciEmail author Anna?Dornhaus 《Behavioral ecology and sociobiology》2012,66(4):583-592
Honey bees (Apis mellifera) use the dance language to symbolically convey information about the location of floral resources from within the nest. To figure out why this unique ability evolved, we need to understand the benefits it offers to the colony. Previous studies have shown that, in fact, the location information in the dance is not always beneficial. We ask, in which ecological habitats do honey bee colonies actually benefit from the dance language, and what is it about those habitats that makes communication useful? In this study, we examine the effects of floral distribution patterns on the benefits of dance communication across five different habitats. In each habitat, we manipulated colonies' ability to communicate and measured their foraging success, while simultaneously characterizing the naturally occurring floral distribution. We find that communication is most beneficial when floral species richness is high and patches contain many flowers. These are ecological features that could have helped shape the evolution of the honey bee dance language. 相似文献
934.
Large-eddy simulation of turbulent flow and dispersion over a complex urban street canyon 总被引:1,自引:0,他引:1
Kiyoung Moon Jeong-Min Hwang Byung-Gu Kim Changhoon Lee Jung-il Choi 《Environmental Fluid Mechanics》2014,14(6):1381-1403
Turbulent flow and dispersion characteristics over a complex urban street canyon are investigated by large-eddy simulation using a modified version of the Fire Dynamics Simulator. Two kinds of subgrid scale (SGS) models, the constant coefficient Smagorinsky model and the Vreman model, are assessed. Turbulent statistics, particularly turbulent stresses and wake patterns, are compared between the two SGS models for three different wind directions. We found that while the role of the SGS model is small on average, the local or instantaneous contribution to total stress near the surface or edge of the buildings is not negligible. By yielding a smaller eddy viscosity near solid surfaces, the Vreman model appears to be more appropriate for the simulation of a flow in a complex urban street canyon. Depending on wind direction, wind fields, turbulence statistics, and dispersion patterns show very different characteristics. Particularly, tall buildings near the street canyon predominantly generate turbulence, leading to homogenization of the mean flow inside the street canyon. Furthermore, the release position of pollutants sensitively determines subsequent dispersion characteristics. 相似文献
935.
Anna Versluis 《Disasters》2014,38(Z1):S94-S109
Following the 2010 Haiti earthquake, more than two million people moved to temporary camps, most of which arose spontaneously in the days after the earthquake. This study focuses on the material assistance people in five Port‐au‐Prince camps reported receiving, noting the differences between assistance from formal aid agencies and from ‘informal’ sources such as family. Seven weeks after the earthquake, 32% of camp dwellers reported receiving no assistance whatsoever; 55% had received formal aid, typically a tent or tarpaulins; and 40% had received informal aid, usually in the form of cash transfers from family living abroad. While people were grateful for any material aid, cash was more frequently considered timely and more effective than aid‐in‐kind. Should this study be indicative of the greater displaced population, aid agencies should consider how they might make better use of cash transfers as an aid modality. 相似文献
936.
Behavioural,emotional, and cognitive responses in European disasters: results of survivor interviews
In the European multi‐centre study BeSeCu (Behaviour, Security, Culture), interviews were conducted in seven countries to explore survivors’ emotional, behavioural, and cognitive responses during disasters. Interviews, either in groups or one‐to‐one, were convened according to type of event: collapse of a building; earthquake; fire; flood; and terror attack. The content analysis of interviews resulted in a theoretical framework, describing the course of the events, behavioural responses, and the emotional and cognitive processing of survivors. While the environmental cues and the ability to recognise what was happening varied in different disasters, survivors’ responses tended to be more universal across events, and most often were adaptive and non‐selfish. Several peri‐traumatic factors related to current levels of post‐traumatic stress were identified, while memory quantity did not differ as a function of event type or post‐traumatic stress. Time since the event had a minor effect on recall. Based on the findings, several suggestions for emergency training are made. 相似文献
937.
PAHs were sampled in ten homes in the Makwanpur region, Nepal. SPMDs and moss bags (Sphagnum girgensohnii) were used as passive samplers. Soot particles on the SPMD surfaces were also analyzed for PAHs. The overall PAH concentrations in SPMDs were significantly higher than those in moss bags. Total PAH mean concentrations of ten houses were 535μg/g lipid for SPMDs and 7.2 μg/g moss (dw) for moss bags. Ratios of phenanthrene/anthracene in indoor SPMDs and particulate matter varied from 2.9 to 3.5 and ratios of fluoranthene/pyrene varied from 1.1 to 1.4. The values for moss bags were respectively 1.7–3.6 and 0.8–2.4. These ratios indicate that the PAHs are from combustion origin. The PAH concentrations in ambient air were estimated as B(a)P TEQs and they were 17–64 times higher than acceptable limit for Finnish community air. Based on PAH levels in the gas phase (SPMD) we may expect PAHs to have an impact on respiratory disease prevalence in Nepalese villages. Both of the sampling methods were feasible in the difficult conditions under which the study was performed. 相似文献
938.
Using a Pathways approach, controversies over environmental and natural resource management are viewed as expressions of alternative, or competing, pathways to sustainability. This supports deeper understanding of the underlying causes of natural resource management controversies. The framework is composed of two elements: the STEPS (Social, Technological, and Environmental Pathways to Sustainability) Pathways approach and frame analysis. Many sustainable development dilemmas are played out in specific places and consequently, the Pathways approach is integrated with a place-based frame analysis. The resulting framework guides empirical investigation in place-based contexts. This theorising about sustainability science can be used to cast light on contested natural resource management issues, in this case mining in northern Sweden. By exposing the range of alternative Pathways to critical norms of sustainable development, we ascertain whether action alternatives are compatible with sustainable futures. The framework provides a way in which sustainability science can better understand the origins of natural resource management conflicts, characterise the positions of the actors involved, identify the potential for cooperation between stakeholders leading to policy resolution and judge what Pathways help or hinder the pursuit of sustainable development. In addition, it can enhance sustainability science by guiding integrative sustainability research at the project scale. 相似文献
939.
David WATSON Carrie MILLER Brian LESTER Kenneth LOWE George SOUTHWORTH Mary Anna BOGLE Liyuan LIANG Eric PIERCE 《Frontiers of Environmental Science & Engineering》2015,9(4):596
Development and demonstration of reliable measurement techniques that can detect and help quantify the nature and extent of elemental mercury (Hg(0)) in the subsurface are needed to reduce uncertainties in the decision-making process and increase the effectiveness of remedial actions. We conducted field tests at the Y-12 National Security Complex in Oak Ridge, Tennessee, USA, to determine if sampling and analysis of Hg(0) vapors in the shallow subsurface (<0.3 m depth) can be used to as an indicator of the location and extent of Hg(0) releases in the subsurface. We constructed a rigid polyvinyl chloride push probe assembly, which was driven into the ground. Soil gas samples were collected through a sealed inner tube of the assembly and were analyzed immediately in the field with a Lumex and/or Jerome Hg(0) analyzer. Time-series sampling showed that Hg vapor concentrations were fairly stable over time, suggesting that the vapor phase Hg(0) was not being depleted and that sampling results were not sensitive to the soil gas purge volume. Hg(0) vapor data collected at over 200 push probe locations at 3 different release sites correlated very well to areas of known Hg(0) contamination. Vertical profiling of Hg(0) vapor concentrations conducted at two locations provided information on the vertical distribution of Hg(0) contamination in the subsurface. We conclude from our studies that soil gas sampling and analysis can be conducted rapidly and inexpensively at large scales to help identify areas contaminated with Hg(0). 相似文献
940.
Izabela Polowczyk Anna Bastrzyk Tomasz Koźlecki Wojciech Sawiński Piotr Rudnicki Adam Sokołowski Zygmunt Sadowski 《Environmental geochemistry and health》2010,32(4):361-366
The aim of this work is to investigate the application of fly ash adsorbent for removal of arsenite ions from dilute solution
(100–1,000 ppm). Experiments were carried out using material from the “Turów” (Poland) brown-coal-burning power plant, which
was wetted, then mixed and tumbled in a granulator to form spherical agglomerates. Measurements of arsenic adsorption from
aqueous solution were carried out at room temperature and natural pH of fly ash agglomerates, in either a shaken flask or
circulating column, to compare two different methods of contacting solution with adsorbent. Adsorption isotherms of arsenic
were determined for agglomerated material using the Freundlich equation. Kinetic studies indicated that sorption follows a
pseudo-second-order model. Preferable method to carry out the process is continuous circulation of arsenite solution through
a column. 相似文献