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111.
This study investigated the relationship between the age of -self‐reported sexual abuse occurrence and the development of post-traumatic stress disorder and/or depressive symptoms in adulthood. Subjects were evaluated for the presence of post-traumatic stress disorder and/or depressive symptoms as well as for a self-reported history of sexual abuse before the age of 18. Results found that relative risk of having severe post-traumatic stress disorder symptoms was 10 times higher in patients reporting sexual abuse after age 12 than in those reporting sexual abuse before age 12. Relative risk of having severe depressive symptoms was higher for those abused before the age of 12 than for those abused after the age of 12. Findings suggest that the impact of reported sexual abuse at different stages of development may lead to distinct psychiatric symptoms in adulthood.  相似文献   
112.
Few studies directly address the consequences of habitat fragmentation for pollinating insect communities, particularly for the neotropical key pollinator group of stingless bees. Most studies on bees have defined habitat fragments as remnant patches of floral hosts or forests, overlooking the nesting needs of bees. Their conclusion is that habitat fragmentation is broadly deleterious; however, there are contrasting results in the literature. Insightful studies on habitat fragmentation and bees should consider fragmentation, alteration and loss of nesting habitats—not just patches of forage plants –, as well as the permeability of the surrounding matrix to interpatch movement. Here we investigated the effects of fragmentation caused by urbanization on stingless bee species’ composition and richness, as well as the permeability of the surrounding matrix. We collected bees from flowering plants and recorded phytosociological variables of five forest remnants (ranging from 64 ha to 900 ha) in southeastern Brazil. Large fragments did not contain more species per unit area than smaller ones; in fact, we found more species in small fragments, most of which were generalist bees. The presence of more habitat generalist stingless bee species was also correlated to the structure of vegetation in these fragments. In conclusion, the quality of the habitat within a fragment (structure of vegetation) as well as the quality of the matrix has a direct relation to the bee species composition. This can be seen in the direct relationship between structural diversity of the environment and age of the fragments. The matrix that holds the most recent fragments, probably due to the sprawl of the city, is more heterogeneous than the one with the oldest fragments. The most heterogeneous matrices have a certain balance between the trees, buildings and bare soil or herbaceous vegetation coverage, making the array less impermeable to bees.  相似文献   
113.
This research explores a causal model of menopausal symptoms in peri- and postmenopausal women. A community sample of 710 women was assessed regarding menopausal symptoms, and sociodemographic, health- and menopause-related, and lifestyle characteristics. Structural equation modelling was used. Menopausal status predicted skin/facial hair changes (β = .156; p <.001), vasomotor (β = .122; p <.001) and sexual symptoms (β = .158; p <.001). Age was significantly associated with cognitive impairment (β = .087; p = .003), aches/pain (β = .072; p = .006), urinary (β = .115; p = .004) and also sexual symptoms (β = .107; p = .021). Several menopausal symptoms are predicted, not only by menopausal status, but also by age progression, among other variables; this should be considered in the context of a well-adapted menopausal transition.  相似文献   
114.
A model which explains data that is subject to sudden structural changes of unspecified nature is presented. The structural shifts are generated by a random walk component whose innovations belong to the normal domain of attraction of a symmetric stable law. To test the model against the stationarity case, several non-parametric, and regression-based statistics are studied. The non-parametric tests are a generalization of the variance ratio test to innovations with heavy-tailed distributions. The tests are consistent and shown to have good finite sample size and power properties and are applied to a set of economic variables.  相似文献   
115.
Earthquakes, evolution, avalanches—even something as simple as grains of sand tumbling down a pile: so many phenomena of nature seem to resist prediction. We still cannot tell when geological stresses will release themselves in a major quake or when the last extra grain of sand will make half the heap avalanche down. But have statisticians been looking in the wrong place? Or are these critical phenomena really inherently unpredictable? They are close to the borders, but still in predictable land, says Osvanny Ramos , one of the authors of an experiment to prove it.  相似文献   
116.
This is an ethnographic study of a shooting that was labeled a drive-by and that resulted in the death of a fifteen-year-old boy. This homicide is seen as an unexpected event that in turn is used as an investigative tool to enhance data collected through observation and in-depth interview methods. I suggest that behaviors revealed by unexpected events can form the basis for theoretical and methodological concepts useful for the study of minority injecting drug users and other hidden populations at high risk to HIV infection and substance abuse.  相似文献   
117.
118.
This paper presents a model for the expansion of transportation networks incorporating specific requirements about population coverage, budget constraints, intermediate goals and origin–destination flows, among others. The model is applicable to the current expansion project of the Spanish high-speed railway network that has been proposed by the Spanish Government under the program Strategic Planning of Infrastructure and Transport (see source [c]).  相似文献   
119.
This paper studies the impact of HIV/AIDS on per capita income and education. It explores two channels on how HIV/AIDS affects income that have not been sufficiently stressed by previous literature: the reduction of the incentives to stay in school due to shorter expected longevity and the reduction in productivity of experienced workers. In the model, individuals live for three periods, may get infected in the second period, and with some probability die of AIDS before reaching the third period of their lives. Parents care for the welfare of the future generations so that they will maximize lifetime utility of their dynasty. The simulations predict that the most affected countries in Sub-Saharan Africa in the future will be, on average, 30% poorer than they would be without AIDS. Schooling will decline in some cases by 40%. These figures are dramatically reduced with widespread medical treatment, as it increases the survival probability and productivity of infected individuals.  相似文献   
120.
This study investigated college students' reports of electronic victimization in friendships and dating relationships. We examined 22 items representing four categories of electronic victimization: hostility, humiliation, exclusion, and intrusiveness. Nearly all participants (92%) reported some electronic victimization in the past year, with males reporting more victimization and females anticipating more distress. Both females and males anticipated more distress from electronic victimization in dating relationships than friendships. More actual experience with electronic victimization related to lower anticipated distress. Electronic victimization was associated with females' alcohol use, even after controlling for other victimization experiences. Discussion focuses on the contextualized nature of electronic victimization, and on the importance of understanding what makes electronic victimization highly distressing for some individuals.  相似文献   
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