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81.
Landscape urbanization threatens plant phylogenetic diversity in the Brazilian Atlantic Forest 总被引:1,自引:0,他引:1
Valdecir Silva-Junior Danielle G. Souza Rubens T. Queiroz Luiz G. R. Souza Elâine M. S. Ribeiro Bráulio A. Santos 《Urban Ecosystems》2018,21(4):625-634
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation. 相似文献
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83.
A number of studies to better understand the complex physiological mechanism involved in regulating body weight have been conducted. More specifically, the hormones related to appetite, leptin and ghrelin, and their association to obesity have been a focus of investigation. Circadian patterns of these hormones are a new target of research. The behaviour of these hormones in individuals subject to atypical working times such as shiftwork remains unclear. Shiftwork is characterized by changes in biological rhythms and cumulative circadian phase changes, being associated with high rates of obesity and metabolic syndrome. Truck drivers, who work irregular shifts, frequently present a high prevalence of obesity, which might be associated with work-related factors and/or lifestyle. In this context, the aim of this paper was to discuss the relationship of body mass index, appetite-related hormones and sleep characteristics in truck drivers who work irregular shifts compared with day workers. 相似文献
84.
Kayla de la Haye Harold D. Green Jr. David P. Kennedy Annie Zhou Daniela Golinelli Suzanne L. Wenzel Joan S. Tucker 《Journal of research on adolescence》2012,22(4):604-616
Homeless youth lack the traditional support networks of their housed peers, which increases their risk for poor health outcomes. Using a multilevel dyadic analytic approach, this study identified characteristics of social contacts, relationships, and social networks associated with the provision of tangible and emotional support to homeless youth (N = 419, M age = 20.09, SD = 2.80). Support providers were likely to be family members, sex partners, or non–street‐based contacts. The provision of support was also associated with contacts' employment and homelessness status, frequency of contact, shared risk behaviors, and the number of network members that were homeless and employed. The results provide insights into how homeless youth could be assisted to develop more supportive social networks. 相似文献
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86.
O. Flores Baquero A. Jiménez Fdez. de Palencia A. Pérez Foguet 《Social indicators research》2016,127(2):741-759
Measuring access to water in the Sustainable Development Goals era involves taking into account the human rights framework. Therefore, its content should be considered to conceptualize the level of service through adequate indicators and to follow-up inequities reduction at global, national and local level. This research develops and tests a methodology to measure intra-community disparities based on human right to water normative criteria through a stratified sampling, splitting households served by community based organizations and those self-provided. This approach implies considering much reduced populations, thus special care needs to be taken with sample sizes and uncertainty of estimators. The proposed methodology is practical to locate and accurately characterize minority sectors within rural communities and allows moving beyond central-tendency estimators. It implies higher costs for field data collection than traditional approaches, but this can be assumed given the relevance of the approach from a human rights perspective, which calls for adequate tools for equity-oriented policy making at local level. The research point out how results might be used to shape decision-making processes. 相似文献
87.
The purpose of this study was to assess the benefits of an exercise program associated to the educational phase of the "Back School Program" in the quality of life of workers from a cigar factory. This is a case study conducted over four months with three activities a week, two times a day, with the third day devoted to educational activities, focusing on healthy lifestyle, correct posture, postural orientations, daily living and work activities, work motivation, and other issues. 相似文献
88.
This paper presents an assessment with simulated activities with the aim of analyzing the perception of ease / difficulty of the use of faucets (taps) handles by 180 Brazilian adults. Five different handles faucets were activated for subsequent collection of perceptual data. The procedures were based on main recommendations for biomedical ethics and human research. The results indicate that handles with levers are significantly (p ≤ 0.05) easier to use. The most difficult are characterized by not having support points for the rotation (levers) or more points of pressure concentration in the hand. 相似文献
89.
Comfort is an issue that has gained relevance within the aeronautical industry due to the necessity of manufacturers and airline companies of differentiating themselves in a market that has become more and more competitive each day. This study's aim is to analyze the comfort/discomfort of passengers, based on the analysis of the activities performed in the aircrafts' cabin during real flights, in order to create ergonomics requirements and a methodology of comfort analysis. The study has been performed during domestic commercial flights, and the adopted data collection techniques have been: the application of 219 questionnaires to passengers, 44 registrations of postures and actions through filmings and 12 semistructured interviews. The method has made possible the reconstruction of the user's action course in performing activities in real flight situations, and the calculation of the area occupied by the passenger during his or her actions. The integrated analysis of the results corroborates data from previous studies in which both the space made available to each passenger and the activity performed interfere in their perception of comfort. From this study it has been concluded that the method constitutes itself as an innovative tool within the process of aircrafts' cabins project enabling the calculation of the action space based on the reconstructed course. 相似文献
90.
Thomas de Vroome Maykel Verkuyten Borja Martinovic 《The International migration review》2014,48(1):76-102
This study examines immigrants' identification with the host country. We use survey data of more than 1,700 Turkish and Moroccan immigrants and more than 2,200 natives in the Netherlands. We answer four main questions in this study. First, do immigrants have lower national identification than natives? Second, does the level of national identification differ between immigrant groups? Third, do economic and social integration similarly affect national identification among immigrants and natives? And fourth, what are important additional determinants of national identification among immigrants? The results show that, compared to Dutch natives, Turkish but not Moroccan immigrants have lower national identification. Being employed and socially integrated is associated with higher national identification among immigrants as well as natives, but only among immigrants is higher occupational status associated with higher national identification. For immigrants, Dutch language proficiency, perceived discrimination, and contact with natives proved to be important conditions for national identification. 相似文献