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131.
The role of badges as indicators of contest ability has been previously described. In hummingbirds, the exhibition of a badge is expected to save energy expenditure in agonistic interactions and to favor energy intake. Here, we investigate whether variable supercilium size in the white-eared hummingbird has a role in dominance status signaling. Firstly, 45 hummingbird males were captured and their superciliums were photographed to investigate variation in size and any possible allometric relationships. Secondly, 42 male birds were used to analyze whether the supercilium has a role in dominance status signaling in a dyadic contest. We found that supercilium size varied continuously but that despite variability between individuals, there was no relationship between supercilium size and body size. However, our dyad experiment indicated that birds with larger badges were able to make more visits to the feeders than individuals with smaller badges. We suggest a status signaling function of the supercilium.  相似文献   
132.
The composition of the opaque and translucent bands in the otoliths of European hake (Merluccius merluccius) from three different populations (Celtic Sea, Galicia shelf and Cretan Sea) was analysed with wavelength dispersive spectrometry (WDS) and differences in Ca, Sr and Na were compared. The translucent bands (annual marks and checks altogether) were significantly richer in Sr and Ca and significantly poorer in Na than opaque bands. Results support the idea of a more compact arrangement of crystals in translucent bands compared to opaque. Analyses did not help to discriminate between putative annual marks and checks. Clear differences in the range of Sr/Ca variation across the otolith as well as in the composition of the otolith core were observed among the three populations. As a result it was possible to discriminate the natal origin of each fish using the composition of the otolith core in Ca, Sr and Na. Nevertheless, the overall pattern across the otolith was similar among the three populations suggesting the existence of ontogenetic trends. Variation of Na/Ca ratios was largely uninformative. Based on these results, a conceptual model for hake is proposed which integrates the different sources of otolith Sr/Ca variation: ambient Sr/Ca, endogenous cues (ontogeny) and exogenous cues (environment).  相似文献   
133.
The purpose of this investigation was to quantify the potential of natural gas to reduce emissions from stationary combustion sources by analyzing the case study of the metropolitan region of Santiago, Chile. For such purposes, referential base scenarios have been defined that represent with and without natural gas settings. The method to be applied is an emission estimate based on emission factors. The results for this case study reveal that stationary combustion sources that replaced their fuel reduced particulate matter (PM) emissions by 61%, sulfur oxides (SOx) by 91%, nitrogen oxides (NOx) by 40%, and volatile organic compounds (VOC) by 10%. Carbon monoxide (CO) emissions were reduced by 1%. As a result of this emission reduction, in addition to reductions caused by other factors, such as a shift to cleaner fuels other than natural gas, technological improvements, and sources which are not operative, emission reduction goals set forth by the environmental authorities were broadly exceeded.  相似文献   
134.
Extractive reserves constitute an innovative approach to match conservation and development objectives, which were originally envisaged as part of a land struggle by forest dwellers in Brazil. In spite of the idea's popularity and the attempts to apply the concept to different tropical regions, there has been little analysis of the combined conservation and development performance of extractive reserve programs. We present a detailed analysis of deforestation and demographic and socioeconomic changes in Alto Juruá, the first extractive reserve created in Brazil in 1990. Forest cover has remained fairly stable. Population has declined slightly, with some internal displacements. The cash economy base has shifted from the original rubber production to a diversified portfolio of agriculture and livestock, and there has been a dramatic rise in nonagrarian income. We conclude that the Reserve represents a very dynamic setting with positive conservation and development outcomes during its first decade.  相似文献   
135.
This 8-week study evaluates the effects of customized foot orthoses on work-related musculoskeletal disorders (WMSDs) of metal industry workers. These WMSDs were evaluated applying the Nordic musculoskeletal questionnaire (NMQ) at three different times (start, 4th week and 8th week) and additional questions were also formulated to obtain information about adaptation, fatigue, comfort and possible improvements. According to the NMQ results, statistical significance was found in the improvements after 4?weeks (p?<?0.05 in two areas, p?<?0.01 in three areas, p?<?0.001 in two areas and no significance in the other two) and after 8?weeks (p?<?0.01 in three areas, p?<?0.001 in four areas and no significance in the other two). The additional questions indicated fatigue reduction (both in general and in lower extremity), comfort level increase (after the adaptation period) and good acceptance, according to workers’ answers, suggesting customized orthoses can be effective in reducing and preventing WMSDs in several body regions.  相似文献   
136.
137.
The concentrations of Hg in three groups of algae (Phaeophyta, Chlorophyta, and Rhodophyta) found in the Canary Islands littoral were determined. The mean concentrations found were, respectively: Phaeophyta: 0.13 mg kg−1 (range 0.01 to 2.30 mg kg−1); Chlorophyta: 0.13 (range 0.025 to 0.36 mg kg−1); Rhodophyta: 0.11 mg kg−1 (range 0.02 to 0.28 mg kg−1). There are no relevant differences in the contents of Hg at group level and at species level, only a sample of Phaeophyta presents an abnormally high concentration (>1 mg kg−1), corresponding to a sampling station nearby an urban drain.  相似文献   
138.
139.
During the last decade, Sustainability Reporting (SR) has been increasingly adopted by corporations worldwide. This is evidenced by the adoption of several guidelines, such as the ISO 14000 series, the Social Accountability 8000 standard, and the GRI Sustainability Guidelines. SR shows promise to help corporate leaders and their employees to contribute towards achieving sustainable societies. However, most of the guidelines and standards address sustainability issues through comparmentalisation, thereby, leading to the separation of the economic, environmental, and social dimensions. Due to these divisive approaches, holistic assessments of the effects of their efforts are seldom properly integrated into coporate decisions and procedures to make improvements for example through Cleaner Production, Worker Health and Safety, Consumer Safety, and reductions in the negative short and long-term Social and Environmental Impacts.This paper analyses SR reports from three companies with the help of Grounded Theory's constant comparative analysis. This analytical framework helped the authors to systematically assess the degree to which the companies addressed economic, ecological and social issues separately or in an integrated and inter-linked manner. From the inter-linkages found, a new category is proposed to be added to future SR. This new category can help corporate SR planners and researchers on sustainability reports to better understand how the company leaders understand their responsibilities with regard to SD. These inter-connectednesses are highly relevant in many short and long-term dimensions of supply chain management, global warming, ecological disruption and societal equity issues, especially with regard to the local, national and global energy issues of fuels and oils, the central themes of the conference at which this paper was originally presented. It also plays a key role in real, long-term changes towards Sustainability, where the time dimension plays a key role in human survival on Planet Earth.  相似文献   
140.
Conclusions  The results are at least as good as those obtained with much more sophisticated models. Furthermore, the models can be easily run on a simple PC. This approach may provide a good diagnostic network (as seen in Bilbao) with real-time, short-term prognostic capabilities for a given location. The models have been built for Bilbao and are applicable only in this location. However, using the same methodology, similar results could be obtained in other environments if a good diagnostic network is available. The full paper is published in the Internet journal ‘Gate to EHS (Environmental and Health Science)’, in June 2001, and can be called up and cited by way of the DOI:http://dx.doi.org/10.1065/ehs2001.06.009  相似文献   
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