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391.
Facilities life extension has caught the attention among the capital-intensive industries, like oil and gas. By extending the life cycle of the industrial assets, a wide range of benefits is obtained, comparing with other life ending management strategies. This article first contextualizes the implementation of the life extension concept in the oil and gas industry, showing global data about life extension. Despite the importance of the ageing process, due to its great economic impact and the risk it poses to the production sector, regulatory entities, even in countries more advanced in that sector or that have already experienced the extension process, developed only superficial material about the topic without defining a structured methodology for the assessment of the possibility of useful life extension. The available references do not allow a comprehensive analysis of that possibility, which highlights the importance the methodology proposed. Thus, this article proposes a guideline for the life extension process management, strengthening a framework containing the main evaluation stages, aiming to facilitate the analysis of issues related to ageing and to support the decision-making process. Lastly, real case studies regarding current life extension processes submitted to the Brazilian regulatory body were evaluated against the proposed framework stages, evidencing their lack of necessary details to support the decision-making. Upon the realization that the real cases identified do not allow for the assessment of the contribution and adequacy of the proposed framework in its entirety, the same was also applied to a hypothetical case. The latter was developed based on facts reported by a major operator in Brazil. The result was the determination that the use of the proposed methodology transformed the assessment of the possibility of life extension into a systematic and transparent process, leading to easier and better-founded decision-making procedures, and improving the management of the asset during its extended life.  相似文献   
392.
A workshop was held in Berlin September 12–14th 2012 to assess the state of the science of the data supporting low dose effects and non-monotonic dose responses (“low dose hypothesis”) for chemicals with endocrine activity (endocrine disrupting chemicals or EDCs). This workshop consisted of lectures to present the current state of the science of EDC action and also the risk assessment process. These lectures were followed by breakout sessions to integrate scientists from various backgrounds to discuss in an open and unbiased manner the data supporting the “low dose hypothesis”. While no consensus was reached the robust discussions were helpful to inform both basic scientists and risk assessors on all the issues. There were a number of important ideas developed to help continue the discussion and improve communication over the next few years.  相似文献   
393.
China is an illustrative—and extreme—case of the difficulties of balancing the pursuit of economic, social, and environmental objectives. In 2003 it adopted a form of Strategic Environmental Assessment (SEA) for its plans and programs (referred to here as PEIA) with the aim of moving towards greater environmental sustainability. The literature has explored primarily the issue of methods and legal procedures. This research contributes to the analysis of PEIA through a different set of interpretative lens. Drawing on recent developments in the theory and practice of SEA, I propose a conceptualization of SEA effectiveness that combines direct and incremental impacts, and a need for context-specific systems as a way to focus on the relationship between assessment, planning, and their context, and thus maximize effectiveness. This framework underpins the analysis of China’s experience, which I explore with the help of interview material and the literature. The result is an evaluation of the strengths and weaknesses of PEIA in terms of its purpose, assessment concept, process, and methods. The detailed analysis of six aspects of the context helps explain the origin of such shortcomings, and identify opportunities for its improvement. I conclude defining elements of a context-specific system for SEA that seeks to maximize the opportunity for incremental, as well as direct, effectiveness in China.  相似文献   
394.
The aim of this paper is to evaluate two agroindustrial productive processes in their entirety (one organic and one semi-industrial), focusing on the comparison of impacts derived from the inputs and outputs of the system (life cycle assessment, LCA), integrated with a physical evaluation of the resources and natural services, on a common basis (emergy). Methods based on the joint use of LCA and emergy evaluation are useful, as they measure the contribution of environmental services and products to the productive process thus focusing primarily on the environmental impact of emissions and non-renewable energy inputs. The complementarity of the methods used in this paper contributes important elements and information useful for the comprehension of the organization of agriculture within Siena's territory. The results show important elements and useful information: (1) for the comprehension of the two agroecosystems' organization; (2) for the use of the energy flows that determine their development. Moreover, the combined use of emergy and LCA gives a comparative thermodynamic performance evaluation between organic and semi-industrial farming.  相似文献   
395.
The Environmental Impact Assessment (EIA) procedure should predict and identify the major impacts of a project development that may cause specific spatial and temporal effects. Early in the EIA, the scoping stage provides all the relevant information on the impacts of the project alternatives. In particular, potential effects on the territorial network such as habitat connectivity loss and accessibility improvements should be taken into account in the various proposed layout alternatives when evaluating transport infrastructure projects. However, several authors have identified deficiencies in practice. The aim of this article is to provide a methodology for the assessment of these territorial impacts using adequate indicators in the early stages of the EIA procedure.

The proposed method is based on a comparison of a range of alternative layouts for a railway line linking two population centres, using indicators calculated with geographic information systems. The methodology was applied to a case study – the rail link between Huelva (Spain) and Faro (Portugal) – and the high speed rail (HSR) and conventional rail were evaluated in different layouts. The method was effective in spatially identifying significant impacts on accessibility improvements, which occurred closer to the cross border area. The conventional railway alternatives have similar accessibility values to the HSR. The results also reveal that connectivity loss is not limited to the area around the infrastructure, but extends throughout the territory. The results are at variance with the initiative proposed by Spanish and Portuguese transport decision-makers, and raise the possibility of selecting a conventional railway option. An adequate territorial evaluation methodology enables the new action to be correctly assessed, and supplies the information required to propose the most suitable alternative from a socio-economic and environmental standpoint, regardless of whether this proposal was initially included in the transport policy.  相似文献   

396.
Species where most but not all females mate monandrously can provide insight into the potential factors both promoting and restricting polyandry. Polyandry is typically explained by direct and/or indirect benefits models; however, polyandry may also confer costs via sexually antagonistic processes. The fitness of polyandrous and monandrous females may also vary with environmental conditions, such as availability of water. For some lepidopterans, water is a vital resource that increases fecundity and may be a direct benefit of multiple mating. Male lepidopterans transfer large spermatophores that may be an important water source for females, particularly for species living in water-depauperate environments. In such species, multiple-mating females may increase their reproductive output. We examined the fitness consequences of multiple mating in the almond moth, Cadra cautella. Males transfer substantial spermatophores; these have a large chitinous process attached, which decrease female longevity. To assess the impact of female mating treatment and water availability on female fitness, females mated once or twice, either with the same or different males, with half the females in each treatment receiving water. Water-fed females had dramatically increased fecundity, but we found no fitness benefits of multiple mating. Male longevity decreased with increased mating frequency and potentially his level of reproductive investment. Water-deprived females that mated twice died sooner than once-mated females, while multiple-mating females that received water lived longer than their water-deprived counterparts. It is interesting to note that the male’s spermatophore process did not affect female fitness or longevity. Why polyandry is maintained in this species is discussed.  相似文献   
397.
Facultative joint colony founding by social insects provides opportunities to analyze the roles of genetic and ecological factors in the evolution of cooperation. Although cooperative nesting is observed in range of social insect taxa, the most detailed studies of this behavior have been conducted with Hymenoptera (ants, bees, and wasps). Here, we show that foundress associations in the haplodiploid social thrips Dunatothrips aneurae (Insecta: Thysanoptera) are most often comprised of close relatives (sisters), though groups with unrelated foundresses are also found. Associations among relatives appear to be facilitated by limited female dispersal, which results in viscous population structure. In addition, we found that per capita productivity declined with increasing group size, sex ratios were female-biased, and some female offspring apparently remained in their natal domicile for some time following eclosion. D. aneurae thus exhibits a suite of similarities with eusocial Hymenoptera, providing evidence for the convergent evolution of associated social and life-history traits in Hymenoptera and Thysanoptera.  相似文献   
398.
Flight distance of urban birds, predation, and selection for urban life   总被引:3,自引:1,他引:3  
Numerous species have adapted to humans, especially invasive species associated with humans in towns and cities. Short flight distances of populations adapted to urban environments reflect changes in behavior and physiology, reflecting phenotypic plasticity or evolution. Here, I tested the hypothesis that the decrease in flight distance to a potential predator (an approaching human) reflected adaptation to urbanization, using a data set of flight distances of 44 common species of European birds in different stages of adaptation to urban environments. Urban populations had consistently shorter flight distances than rural populations of the same species. Variation in relative flight distance of urban populations was predicted by the number of generations since urbanization, as expected by a gradual process of adaptation. Furthermore, species with relatively large populations in urban environments would be an indication of local adaptation to urban environments. Relative flight distance of urban population was shorter for species with large populations in urban compared to rural habitats. Species that had adapted to urban environments as shown by short flight distances were less susceptible to predation by the European sparrowhawk Accipiter nisus than species with relatively long flight distances in urban populations. These findings provide evidence consistent with the hypothesis that recent changes in the tameness of urban birds, as reflected by their relatively short flight distances, is an adaptation to the novel urban environment. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
399.
Insect larvae increase in size with several orders of magnitude throughout development making them more conspicuous to visually hunting predators. This change in predation pressure is likely to impose selection on larval anti-predator behaviour and since the risk of detection is likely to decrease in darkness, the night may offer safer foraging opportunities to large individuals. However, forsaking day foraging reduces development rate and could be extra costly if prey are subjected to seasonal time stress. Here we test if size-dependent risk and time constraints on feeding affect the foraging–predation risk trade-off expressed by the use of the diurnal–nocturnal period. We exposed larvae of one seasonal and one non-seasonal butterfly to different levels of seasonal time stress and time for diurnal–nocturnal feeding by rearing them in two photoperiods. In both species, diurnal foraging ceased at large sizes while nocturnal foraging remained constant or increased, thus larvae showed ontogenetic shifts in behaviour. Short night lengths forced small individuals to take higher risks and forage more during daytime, postponing the shift to strict night foraging to later on in development. In the non-seasonal species, seasonal time stress had a small effect on development and the diurnal–nocturnal foraging mode. In contrast, in the seasonal species, time for pupation and the timing of the foraging shift were strongly affected. We argue that a large part of the observed variation in larval diurnal–nocturnal activity and resulting growth rates is explained by changes in the cost/benefit ratio of foraging mediated by size-dependent predation and time stress.  相似文献   
400.
Female choice and male–male aggression are two modes of sexual selection that can lead to elaboration of male morphological and behavioral traits. In lek-mating species, male mating success is often strongly skewed, and it is puzzling why variation in male traits is still observed given directional female choice. If male traits correlated with reproductive success are honest signals of male quality, there may be survival costs associated with the expression of those traits. In this study, we examined whether morphological, behavioral, and territorial traits are correlated with male mating success and survival in the lek-mating greater prairie-chicken (Tympanuchus cupido). We introduce a novel application of multinomial discrete choice models for analysis of female mate choice behavior. We found that behavioral and territorial attributes showed 6.5 times more variability among males than morphological traits. Both display and aggressive behaviors were strong predictors of male mating success, suggesting that both female choice and male–male aggression were important in determining mating success among male greater prairie-chickens. Moreover, annual survival of male prairie-chickens was independent of mating success and male traits. Females appear to be choosing males based on behavioral traits where large variation exists between males (coefficient of variation >30%). Behavioral traits were the most important factor in determining mating success of male prairie-chickens, but the mechanism underlying this relationship is unknown. In the future, experimental manipulations of male hormones or parasite loads could bridge the proximate mechanisms and ultimate consequences of factors mediating male mating success in lek-mating grouse.  相似文献   
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