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1.
AIDS and Behavior - While pre-exposure prophylaxis (PrEP) is a key HIV prevention tool for adolescents and young adults (AYAs), its initiation and sustained use is shaped by AYAs’ unique...  相似文献   
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Limitations in current capabilities to constrain aerosols adversely impact atmospheric simulations. Typically, aerosol burdens within models are constrained employing satellite aerosol optical properties, which are not available under cloudy conditions. Here we set the first steps to overcome the long-standing limitation that aerosols cannot be constrained using satellite remote sensing under cloudy conditions. We introduce a unique data assimilation method that uses cloud droplet number (N(d)) retrievals to improve predicted below-cloud aerosol mass and number concentrations. The assimilation, which uses an adjoint aerosol activation parameterization, improves agreement with independent N(d) observations and with in situ aerosol measurements below shallow cumulus clouds. The impacts of a single assimilation on aerosol and cloud forecasts extend beyond 24 h. Unlike previous methods, this technique can directly improve predictions of near-surface fine mode aerosols responsible for human health impacts and low-cloud radiative forcing. Better constrained aerosol distributions will help improve health effects studies, atmospheric emissions estimates, and air-quality, weather, and climate predictions.  相似文献   
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Maltreated children with reactive attachment disorder (RAD) have severe problems with social relationships and affect regulation. An association between early maltreatment and changes in the daily rhythm of cortisol secretion has already been reported for maltreated toddlers. We sought to find out whether such changes were apparent in school-age children with symptoms of RAD, who had experienced early maltreatment but were currently adopted in well-functioning families. We recruited 66 children: 34 adopted children, aged 5–12 years, with an early history of maltreatment and with social difficulties such as indiscriminate friendliness; and 32 age- and sex-matched comparison children with no history of maltreatment or social difficulties. Daily rhythms of cortisol production were determined from saliva samples collected over 2 days. The adopted group had significantly lower absolute levels of cortisol compared to the control group, but a typical profile of cortisol secretion. There was no association between cortisol secretion and symptom scores for psychopathology.  相似文献   
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We draw attention to a number of important considerations in the arguments about screening and outcome of intervention in children with autism and other developmental disorders. Autism screening in itself never provides a final clinical diagnosis, but may well identify developmental deviations indicative of autism—or of other developmental disorders—that should lead to referral for further clinical assessment. Decisions regarding population or clinic screening cannot be allowed to be based on the fact that prospective longitudinal RCT designs over decades could never be performed in complex developmental disorders. We propose an alternative approach. Early screening for autism and other developmental disorders is likely to be of high societal importance and should be promoted and rigorously evaluated.  相似文献   
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Vitamin D deficiency has been proposed as a possible risk factor for developing autism spectrum disorder (ASD). 25-Hydroxyvitamin D3 (25(OH)D3) levels were examined in a cross-sectional population-based study in the Faroe Islands. The case group consisting of a total population cohort of 40 individuals with ASD (aged 15–24 years) had significantly lower 25(OH)D3 than their 62 typically-developing siblings and their 77 parents, and also significantly lower than 40 healthy age and gender matched comparisons. There was a trend for males having lower 25(OH)D3 than females. Effects of age, month/season of birth, IQ, various subcategories of ASD and Autism Diagnostic Observation Schedule score were also investigated, however, no association was found. The very low 25(OH)D3 in the ASD group suggests some underlying pathogenic mechanism.  相似文献   
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OBJECTIVES: To evaluate evidence for the effectiveness of female controlled physical and chemical barrier methods in preventing STI/HIV transmission, to examine recent reviews on microbicide development, and to highlight promising research directions. To discuss challenges in conducting effectiveness research and in translating results to public health intervention. METHODS: Systematic review of articles that examined the disease prevention effectiveness of at least one female controlled barrier method. Review of conference abstracts that presented clinical and preclinical microbicide data. RESULTS: Randomised controlled trials provide evidence that female condoms confer as much protection from STIs as male condoms. Observational studies suggest that the diaphragm protects against STI pathogens. Several microbicide effectiveness studies are under way and new directions, such as adaptation of therapeutic agents as preventive products, are being examined. Substantial attention is now given to product formulation and novel delivery strategies. Combining microbicide products with different mechanisms of action as well as combining chemical and physical barriers will be necessary to maximise prevention effectiveness. CONCLUSIONS: Increased investment in the development and identification of female controlled barrier methods offers promise that additional products will be available in the years ahead. Generalizing trial results to a community setting, promoting products that may be less effective than male condoms, and bringing an effective product to scale introduce public health challenges that warrant attention. The need for female controlled barrier methods that provide women with the opportunity to take an active role in reducing their STI/HIV risk are urgently needed and constitute an essential tool to prevent continued spread of these infections.  相似文献   
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The objective of this study was to examine the relationship between contraceptive method choice, sexual risk and various demographic and social factors. Data were collected on 378, 15- to 24-year-old women, recruited from health clinics and through community outreach in Northern California. Logistic regression analysis was used to estimate the association of predictors with contraceptive method used at last sex. Asian and Latina women were less likely to use any method. Women who were raised with a religion, or thought they were infertile, were also less likely to use any method. Women with multiple partners were generally less likely to use any method, but were more likely to use barrier methods when they did use one. Few women (7%) were dual method users. Women appear to act in a rational fashion within their own social context and may use no methods at all or use methods that are less effective for pregnancy prevention but offer more protection from sexually transmitted infections.  相似文献   
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