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951.
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953.
Ian?H.?RowlandsEmail author 《Mitigation and Adaptation Strategies for Global Change》2011,16(7):749-773
This article analyses the debate associated with the ancillary impacts of climate change mitigation options in developing
countries, with a particular focus upon Africa’s 34 least developed countries. While these countries’ emissions of greenhouse
gases are relatively small (and they do not have emission limitation commitments in the current international regime), inattention
to the mitigation agenda would mean that developing countries both miss potential funding opportunities and fail to ‘climate-proof’
their development strategies. A focus, therefore, upon the short-term, local, developmental impacts that serve to change the
relative attractiveness of different mitigation options from the perspective of the developing country is in these countries’
current strategic interests. In this article, I examine three energy-related climate change mitigation options: improved cookstoves,
carbon-free electricity and improved energy efficiency in industry. Key ancillary impacts are better indoor air quality, better
outdoor air quality and job creation (respectively). Further work to strengthen the evidence base regarding these impacts
needs to be undertaken, potentially drawing upon broader work that has already been completed. Thus, in conclusion, a call
for cross-fertilisation of information between heretofore disparate research communities is made. Additionally, the development
of an integrated research agenda, forging linkages among cookstoves, indoor air quality and climate change mitigation research
communities in Africa’s least developed countries, is identified as a priority. 相似文献
954.
Proline is a proteinogenic amino acid in which the side chain forms a ring, the pyrrolidine ring. This is a five-membered ring made up of four carbons and one nitrogen. Here, we study the evolutionary significance of this ring size. It is shown that the size of the pyrrolidine ring has the advantage of being nearly planar and strain-free, based on a general mathematical assertion saying that the angular sum of a polygon is maximum if it is planar and convex. We also provide a sketch of the proof to this assertion. The optimality of the ring size of proline can be derived from a triangle inequality for angles. Quasi-planarity is physiologically significant because it allows an easier and evolutionarily old type of fit into binding grooves of proteins with which proline-rich proteins interact. Finally, we present a comparison with other planar, nearly planar and non-planar biomolecules such as neurotransmitters, hormones and toxins, involving, for example, aromatic rings, cyclopentanone and 1,3-dioxole. 相似文献
955.
Peter Stigson Anders Hansson M?rten Lind 《Mitigation and Adaptation Strategies for Global Change》2012,17(6):601-619
The potential for CO2 emission reductions through carbon capture and storage (CCS) is depending on investments that can bring the technology from the current R&D through to commercial applications. The intermediate step in this development is demonstration plants that can prove the technical, economic, social, and ecological feasibility of CCS technologies. Based on a CCS stakeholder questionnaire survey and a literature review, we critically analyse discrepancies regarding perceptions of deployment obstacles and experiences from early demonstration plants. The analysis identifies discrepancies between CCS policies versus important deployment considerations and CCS stakeholder policy demands. The discrepancy gap is emphasised by lessons from restructured, postponed, and cancelled CCS projects. To bridge this cognitive gap towards proving CCS through demonstration activities, the article highlights policy implications of establishing a broad understanding of deployment obstacles. Attention to these obstacles is important for policymakers and industry in channelling efforts to demonstrating CCS, hence validating the current focus on CCS as a key abatement potential. Under present conditions, the findings question the robustness of current CCS abatement potential estimates and deployment goals as established by policymakers and in scenarios. 相似文献
956.
Asako?K.?Azuma Rie?Tomioka Chisato?TakenakaEmail author 《Environmental geochemistry and health》2016,38(2):437-448
The young leaves of Clethra barbinervis Sieb. et Zucc, which is a deciduous tree species found in secondary forests widely in Japan, are used in spring as a local traditional food by local populations, and the bark of this plant is also preferred by sika deer, Cervus nippon. However, C. barbinervis has been known to accumulate heavy metals in its leaves. Then, we aimed to clarify the characteristics of microelement contents in C. barbinervis and to discuss the value of this species as food for humans and animals through the analysis of seasonal changes and distribution in various organs of C. barbinervis growing under two different geological conditions. We found that C. barbinervis is an accumulating and tolerant plant for Ni, Co and Mn. It accumulates Ni from serpentine soil containing Ni at high concentration, and Co and Mn from acidic soils based on crystalline schist. The seasonal variation in element concentrations in leaves indicates that the young leaves contain Cu at high concentration and that eating them in spring season may be advantageous to humans, due to the associated increase in Cu intake. The high concentrations of Cu and Zn in the bark of C. barbinervis might explain why deer prefer to eat the bark of this species. 相似文献
957.
Mohammad?Jadidi Farzad?Bazdidi-TehraniEmail author Mohsen?Kiamansouri 《Environmental Fluid Mechanics》2016,16(3):575-601
In the present article, the potential of embedded large eddy simulation (ELES) approach to reliably predict pollutant dispersion around a model building in atmospheric boundary layer is assessed. The performance of ELES in comparison with large eddy simulation (LES) is evaluated in several ways. These include a number of qualitative and quantitative comparisons of time-averaged and instantaneous results with wind tunnel measurements supplemented by statistical data analyses using scatter plots and standard evaluation metrics. Results obtained by both LES and ELES approaches show very good agreement with the experiment. However, addition of turbulence to mean flow at Reynolds averaged Navier–Stokes (RANS)–LES interface in ELES approach not only increases the turbulence intensity, it also results in larger values of turbulent kinetic energy (TKE) as well as a shorter reattachment length in the wake region. Accordingly, higher levels of TKE predicted by ELES increase the local intensity of concentration leading to shorter plume shapes as compared with LES. In general, ELES shows better agreement with experiment on the surfaces of model building and also in the downstream wake region. In terms of computational costs, the CPU time required to obtain statistical values in ELES is about 49 % lower than that of LES and the number of iterations per time step is also reduced by 55 % as compared with LES. 相似文献
958.
Massimo?VentrucciEmail authorView authors OrcID profile
return OK on get Daniela?Cocchi Marian?Scott 《Environmental and Ecological Statistics》2016,23(4):565-584
Urban sprawl and its evolution over relatively short periods of time demands that we develop statistical tools to make best use of the routinely produced land use data from satellites. An efficient smoothing framework to estimate spatial patterns in binary raster maps derived from land use datasets is developed and presented in this paper. The framework is motivated by the need to model urbanization, specifically urban sprawl, and also its temporal evolution. We frame the problem as estimation of a probability of urbanization surface and use Bayesian P-splines as the tool of choice. Once such a probability map is produced, with associated uncertainty, we develop exploratory tools to identify regions of significant change across space and time. The proposal is used to study urbanisation and its development around the city of Bologna, Emilia Romagna, Italy, using land use data from the Cartography Archive of Emilia Romagna Region for the period 1976–2008. 相似文献
959.
Edward?A.?RoualdesEmail authorView authors OrcID profile
return OK on get Simon?J.?Bonner Thomas?D.?Whitney James?D.?Harwood 《Environmental and Ecological Statistics》2016,23(2):317-336
The literature on modelling a predator’s prey selection describes many intuitive indices, few of which have both reasonable statistical justification and tractable asymptotic properties. Here, we provide a simple model that meets both of these criteria, while extending previous work to include an array of data from multiple species and time points. Further, we apply the expectation–maximisation algorithm to compute estimates if exact counts of the number of prey species eaten in a particular time period are not observed. We conduct a simulation study to demonstrate the accuracy of our method, and illustrate the utility of the approach for field analysis of predation using a real data set, collected on wolf spiders using molecular gut-content analysis. 相似文献
960.
Simona?Kralj-Fi?erEmail author Jutta?M.?Schneider ?iva?Justinek Sabina?Kalin Matja??Gregori? Stano?Pekár Matja??Kuntner 《Behavioral ecology and sociobiology》2012,66(1):145-151
Sexual cannibalism particularly before mating is costly for the male victim but also for the female aggressor if she risks
remaining unmated. The aggressive spillover hypothesis explains the persistence of this behavior as a maladaptive side effect
of positive selection on aggressiveness in a foraging context. The hypothesis predicts that the occurrence of sexual cannibalism
is explained by female aggressiveness but is not related to male phenotype or behavioral type. An alternative hypothesis invokes
sexual selection and makes the opposite prediction namely that sexual cannibalism is an expression of female choice and should
hence mainly target males of low quality. We tested the above hypotheses on a sexually dimorphic nephilid spider Nephilengys livida, known for male monopolization of females via genital damage, female genital plugging, and mate guarding, by staging mating
trials during which we recorded mating behaviors and occurrences of pre- and postcopulatory cannibalism. We did not restrict
assessment of aggressiveness to the mating and foraging context but also included aggression against same sex conspecifics.
To assess female personalities, i.e., consistent individual differences in behavior including aggressiveness, we repeatedly
tested them for intra-sex aggression, voracity towards prey, locomotory activity, and boldness. Females exhibited consistent
differences in intra-sex aggressiveness, latency to attack prey, and boldness. Aggressive females had shorter latencies to
attack prey and were more active than non-aggressive ones. In contrast to the predictions of the aggressive spillover hypothesis,
females that were aggressive towards prey and towards other females were not more likely to attack a male than non-aggressive
females. In support of the mate choice hypothesis, less aggressive males were more likely attacked and cannibalized than more
aggressive ones. This hints at sexual selection for aggressiveness in males and raises the question of mechanisms that maintain
variation in male aggressiveness. 相似文献