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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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This article reflects on the importance of the relations between state and society in policy-making in the area of public health. Several studies in various sectors such as health, education, and social services have made similar observations on organizational dynamics and the institutionalization of different models of partnerships or contracts, often based on the analytical model of three sectors. Individuals and their networks of relationships, however, remain an almost unexplored dimension in these types of research. Against this backdrop, this study seeks to analyze the movement of HIV/AIDS activists to governmental organizations working in this same field. The analysis raises questions concerning the forms of individual and institutional learning that help to maintain the distinct character of innovation of the Brazilian policy. Professionals who cross the borders hold a different profile once they have accumulated experience working with grassroots and local NGOs, and have also had the chance to be trained and enhance their technical and managerial capacities, since the government has supported NGOs for a long period. When combined, these experiences allow them to maintain relationships with social movements and give them the ability to navigate through the government bureaucracy and handle technical information about fighting AIDS epidemics, making it possible for them to negotiate strategic collaborations reflecting the interests of different groups. Hence, they constantly reflect on the differences between government and social spaces, and keep questioning and modifying their roles in the light of potential and existing complementarities.  相似文献   
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The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of two public Middle School students from Paraíba (Brazil). The target population included 8th grade groups involving 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck and about 90% of the students presented postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints.  相似文献   
5.
Personal Protective Equipment (PPE) is considered the last preferred solution to an Occupational Safety Health (OSH) system. Brazilian OSH legislation assumes and requires PPE usage to neutralize the possibility of pesticide contamination. This study examines the inadequacy of the PPE used in a tomato crop, particularly from the standpoint of thermal comfort. This study made observations regarding heart rate and body temperature in a controlled environment using a treadmill (with and without PPE) of 12 volunteers; and during the process of rural labor (at rest and in normal work routine) of 2 actual rural workers. Comparing the results of the treadmill test (with and without PPE) which tried to reproduce the same level of effort and environmental conditions of the actual rural work, this study demonstrated that PPE makes thermoregulation harder and tympanic temperature reaches higher values with the same level of effort. Moreover, body temperature increases quickly: with PPE it took 15 minutes to raise 1°C in body temperature, compared to 40 minutes without PPE. The results of this study indicated that the use inadequate PPE might pose thermoregulation risk to rural workers.  相似文献   
6.
Into dangerous and complex systems with high degree of interactivity between its components, the variability is present at all time, demanding a high degree of control of its operation. Maintaining or recovering the normality, when the system is under some stress (instability) is a function of Resilience. To cope with prevention, forecast, recovery and with memory of experiences from learned lessons requires some features from the companies. This paper purposes a structure that enables the Total Resilience of a system production that defines the assignments for Workers, Designers and Management Team, according to its features and possibilities. During one year and a half developing studies on ergonomics area of a Brazilian Oil Refinery, several situations were observed and studied using Work Ergonomic Analysis. These situations show actions and strategies that workers use to maintain the system stability. Furthermore, they revealed the importance that these actions are stored in a database of learned lessons from the Company. The research resulted in a broad scheme. It places each of these groups in the process of Total Resilience. It also shows the human like a center of actions that ensure the continuity of the system, main element at Resilience (Anthropocentric View).  相似文献   
7.
The objective of the study was to evaluate the occurrence of Burnout Syndrome in 100 teachers of six public high schools and its correlation with working conditions in a southeast city of Brazil. Characterization of the sample occurred after application of a socio-demographic questionnaire. Evaluation of the working conditions was done by means of an Ergonomic Working Analysis. The presence of Burnout Syndrome was evaluated by means of the Maslach Burnout Inventory. The sample presented the predominance of women, with an average age of 40.4 and the majority married with children. Roughly 50% had less than 10 years of service, and more than half of the teachers taught more than 18 classes per week. Hoarseness after work was principally reported among women, which required many days off for health treatment. Environmental conditions reflect inadequacy in relation to noise, light, humidity and temperature. Presence of pain in the upper limbs was especially high among women. Risk of musculoskeletal disorders in the upper limbs predominated as moderately important to significant. We also identified an average distance walked by teachers of 1.5 Km and an average of 4.2 Kg of school supplies carried between classes. The Burnout Syndrome presented a high score for depersonalization principally among men, but it has association with both sexes. Emotional exhaustion correlates with noise, depersonalization, and personal fulfillment, in addition to the high number of weekly lessons. It can be concluded that Burnout syndrome is present among teachers, principally in terms of depersonalization, deserving the attention of government officials and the schools, as well as the teachers themselves.  相似文献   
8.
This research aimed to study the activity of the HLB's scouts, workers whose function is to identify symptomatic plants, in order to understand the physical constraints, cognitive and organizational involved in accomplishing the task, characterizing the operative approach used to identify diseased plants, and to elucidate what aspects hinder the identification of symptoms. The method adopted for the research was the Ergonomic Analysis of Work--EAW [6]. The results, after validation with the operators and management, allowed understanding the complex relationships between the physical, cognitive and organizational aspects present on activity. Major difficulties were observed mainly in relation to the disposal of the scouts on the platforms and in relation to working hours, at the beginning and end of the journey. Important findings have highlighted strategies, unknown by the organization, used by scouts to locate candidates' trees to the fine analysis of investigation of symptoms. In conclusion, the analysis enable to understand the constraints and find technical and organizational solutions to the survey work on citrus groves as well as it showed signs and symptoms not investigated yet or rarely considered by researchers involved on searches aimed at increasing the ability to diagnose the disease in the field.  相似文献   
9.
The occupational stress is associated with dissatisfaction, excessive demand at work and personal factors. Those factors can reduce work performance and can predispose workers to various diseases. Workers' health may be protected if there is encouragement to face challenges, which may lessen the impact on psychological and somatic stress and thus have greater personal and professional satisfaction. The aim of this study was to evaluate the association between occupational stress and work engagement. Participated in this study 457 male and female workers of a metallurgical industry. Subjects answered personal data, and the Job Stress Scale and Utrecht Work Engagement Scale were applied. Results showed an association between occupational stress and work engagement (P=0,001). The way the individual deals with his frustrations, or rather the work engagement, is associated with the occupational stress.  相似文献   
10.
Clustered binary responses are often found in ecological studies. Data analysis may include modeling the marginal probability response. However, when the association is the main scientific focus, modeling the correlation structure between pairs of responses is the key part of the analysis. Second-order generalized estimating equations (GEE) are established in the literature. Some of them are more efficient in computational terms, especially facing large clusters. Alternating logistic regression (ALR) and orthogonalized residual (ORTH) GEE methods are presented and compared in this paper. Simulation results show a slightly superiority of ALR over ORTH. Marginal probabilities and odds ratios are also estimated and compared in a real ecological study involving a three-level hierarchical clustering. ALR and ORTH models are useful for modeling complex association structure with large cluster sizes.  相似文献   
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