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AbstractEcologists are increasingly aware of the importance of environmental variability in natural systems. Climate change is affecting both the mean and the variability in weather and, in particular, the effect of changes in variability is poorly understood. Organisms are subject to selection imposed by both the mean and the range of environmental variation experienced by their ancestors. Changes in the variability in a critical environmental factor may therefore have consequences for vital rates and population dynamics. Here, we examine ≥90‐year trends in different components of climate (precipitation mean and coefficient of variation (CV); temperature mean, seasonal amplitude and residual variance) and consider the effects of these components on survival and recruitment in a population of Eurasian beavers (n = 242) over 13 recent years. Within climatic data, no trends in precipitation were detected, but trends in all components of temperature were observed, with mean and residual variance increasing and seasonal amplitude decreasing over time. A higher survival rate was linked (in order of influence based on Akaike weights) to lower precipitation CV (kits, juveniles and dominant adults), lower residual variance of temperature (dominant adults) and lower mean precipitation (kits and juveniles). No significant effects were found on the survival of nondominant adults, although the sample size for this category was low. Greater recruitment was linked (in order of influence) to higher seasonal amplitude of temperature, lower mean precipitation, lower residual variance in temperature and higher precipitation CV. Both climate means and variance, thus proved significant to population dynamics; although, overall, components describing variance were more influential than those describing mean values. That environmental variation proves significant to a generalist, wide‐ranging species, at the slow end of the slow‐fast continuum of life histories, has broad implications for population regulation and the evolution of life histories.

Abstract: Five groups of NMRI mice were fed ethanol or sucrose in a nutritionally adequate liquid diet for 9 days. The dietary fat consisted of olive oil with the fatty acid composition 18:1 77%, 18:2 10%, 18:0 and 16:0 12%. The ethanol treated groups received 5% w/v ethanol (E) or isocaloric sucrose (S). Two groups (S‐ and E‐) received the diet without supplement. In two groups (S+ and E +) 7% of the fat was exchanged for arachidonic acid (20:4). In a fifth group (IE +) treated with ethanol and arachidonic acid the diet also contained indomethacin (10 mg/1). The mean intake of ethanol was about 20 g/kg/day. After 9 days animals were killed and liver lipids analyzed after Folch extraction. The post mortem accumulation of prostaglandin E2 in the kidney was measured by GC‐MS. Dietary 20:4 was found to protect mice against fatty liver caused both by a high fat diet alone and in combination with ethanol. The liver triglycerides were 30.7 + 4.3 (S ‐), 46.1+6.9 (E ‐), 6.8 + 0.4 (S +) and 19.4 ±1.8 (E +). Prostaglandin levels in the kidney were depressed by ethanol treatment. Indomethacin gave variable degrees of PG synthesis inhibition. The degree of liver triglyceride accumulation in the IE+ group was inversely propotional to the degree of PG synthesis. The data suggest a role for liver 20:4 cyclooxyganase metabolites in fatty liver caused by high fat diets and ethanol.

Analyse numerique et etude experimentale de l'influence du rapport des temperatures d'une plaque et du fluide sur le nombre de Nusselt d'une couche limite turbulente compressible

AbstractCurrent anthropogenic environmental change causes rapid loss of biodiversity. Although the effects of the main causes of this loss (habitat fragmentation, climate change, and invasive species) on single species have been widely studied, the effects on species interactions are poorly understood. In particular, we do not yet understand how these phenomena affect the evolutionary processes that impact species interactions. Coevolution is a dominant process that organizes the web of life: most species are involved in at least one coevolved interaction. Due to rapid human modification of landscapes it is important to understand how subsequent changes in biotic and abiotic environment and in the level and distribution of genetic variation, as well as changes in population structures, influence the elements of the coevolutionary process. In this review, we synthesize recent development of theoretical work on the coevolution of interacting species with conservation genetics and the impact of anthropogenic environmental changes on single species to address the potential effects of habitat fragmentation, climate change, and invasive species on plant‐herbivore coevolution.

Abstract Social learning is a prerequisite for sustainable energy use. This paper sets out some considerations from learning theory that offer a useful way of looking at domestic energy awareness and at actions to improve energy efficiency and conserve energy. Findings from a survey of residents of an English village that had won an ‘energy-conscious village’ competition are used to illustrate how individual and social learning can occur over a period of time, and how a ‘top down’ initiative may relate to other more informal sources of motivation and information. A model of learning about domestic energy use that incorporates awareness, action and feedback is proposed, and the implications for policy and further research are discussed.

An experiment has been performed, using pulsed dye injection on an aerofoil in a Hele-Shaw cell. The purpose was to observe the form of the trailing-edge flow when the Reynolds number was high enough to permit separation and the initiation of a Kutta condition. The experiment provides a successful confirmation of the existence of a ‘viscous tail’ as predicted by Buckmaster (1970) although there is an unexplained quantitative discrepancy.

Concentrated solar power (CSP) integrated with calcium looping (CaL) technology has garnered significant interest as a solution to mitigate the issue of intermittency in solar power production. However, the deactivation of CaO‐based materials during cycling limits the application of CaL technology on a large scale. Herein, the dynamic characteristics of the CSP‐CaL system indirectly integrated with the s–CO2 Brayton cycle using CaO–ZnO–Na2SO4 composites are studied. Energy analysis shows that the energy storage density varies from 1328.13 to 1232.03 J g−1, and its average value increases by 32.0%. Round‐trip efficiency of the system varies from 40.0% to 39.5%, and its average value increases by 22.6%. Exergy analysis shows that the co‐doping of ZnO and Na2SO4 into CaO enhances the exergy efficiency of the calciner and the heat exchange network, but reduces the exergy efficiency of the carbonator. Exergy round‐trip efficiency of the CSP‐CaL system has slightly decreased from 44.0% to 43.4%, with an average increase of 22.8%. Techno‐economic analysis shows that the levelized cost of electricity for different sizes of CSP‐CaL systems using CaO–ZnO–Na2SO4 ranges from 176.44 to 153.70 $ MWh−1. Therefore, the CaO–ZnO–Na2SO4 composite shows promising prospects for application in solar thermal power generation.

Anticipatory adaptation to climate change requires the impact of future changes in water availability to be investigated prior to deployment of low-carbon electricity generation infrastructure. Here we investigate whether climate change may limit water availability for a proposed coal-fired (CF) power station site with Carbon Capture and Storage (CCS). We find that climate change may pose constraints on water availability, and that regulatory constraints on water abstraction licences may affect CF electricity generation with CCS. The regulatory constraints associated with the current misalignment of water and energy policies are explored through interviews with stakeholders. We find that water availability has not been identified as a potential limiting factor for future CF electricity generation with CCS and that current UK energy policy, combined with economic and historical factors, may exacerbate the water demand of CF electricity generation with CCS. These issues need to be addressed prior to deployment of CCS technology.