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81.
CONTEXT: HIV prevalence is high among South African youth. Health behavior models posit that the perceived level of risk of HIV infection is associated with the level of HIV risk behavior; however, there has been limited research in Sub-Saharan Africa on factors associated with perceived risk or on the relationship between perceived risk and risk behaviors. METHODS: Longitudinal data collected in 2002 and 2005 from 3,017 black, colored and white youth in Cape Town, South Africa, were analyzed using multivariate regression to examine whether a reciprocal relationship exists between sexual experience and perceived HIV risk. Independent variables taken from the 2002 survey were used to predict dependent variables taken from the 2005 survey. RESULTS: In 2005, most youth (82% of males and 83% of females) viewed themselves as being at no or small risk of HIV infection. A reciprocal relationship in which higher perceived HIV risk was associated with a delay in sexual debut (odds ratio, 0.8) and sexual experience was associated with higher perceived risk (1.4) was found for females, but not for males. Knowing someone who had died of AIDS was associated with sexual debut and with an elevated perceived HIV risk among females (1.7 and 1.3, respectively). The associations between race and perceived risk of HIV infection varied by gender. CONCLUSIONS: HIV/AIDS education and prevention programs should consider more carefully how gender and race may intersect to influence risk perceptions and risk behaviors. In addition, possible reciprocal relationships between risk behaviors and risk perceptions should be considered in education and intervention programs.  相似文献   
82.
Bien que les travailleurs s'adonnent à la fois à nombre de tâches formelles et informelles, les recherches centrées sur le comportement organisationnel s'intéressent préférentiellement aux conduites formelles et à leur produit. Quand l'attention se porte sur les comportements informels, c'est généralement pour les atténuer ou les éliminer. On soutient dans cet article que les comportements informels doivent être pris en considération même si c'est la tâche à accomplir qui est l'objet de la problématique. On a, dans deux recherches exploitant des échantillons de 133 et 137 individus, relevé une série de comportements informels et étudié la relation entre leur fréquence d'apparition et la satisfaction. Les implications des comportements informels sont analysées du point de vue de la nature changeante du travail.
Although people at work engage in a number of on-task and off-task behaviours, the preponderance of behavioural research in organisations is directed towards on-task behaviours and the outcomes resulting from them. When attention is paid to off-task behaviours, it is usually directed at decreasing or eliminating such behaviours. The position taken here is that off-task behaviours must be understood even if our concern is with task behaviour. Two studies, with samples of 137 and 133 persons, identified a subset of off-task behaviours and explored the relationship of their reported occurrence to job satisfaction. Implications of off-task behaviour at work are discussed with respect to the changing nature of work.  相似文献   
83.
An advantage of first mention—that is, faster access to participants mentioned first in a sentence—has previously been demonstrated only in English. We report three experiments demonstrating that the advantage of first mention occurs also in Spanish sentences, regardless of whether the first-mentioned participants are syntactic subjects, and regardless, too, of whether they are proper names or inanimate objects. Because greater word-order flexibility is allowed in Spanish than in English (e.g., nonpassive object-verb-subject constructions exist in Spanish), these findings provide additional evidence that the advantage of first mention is a general cognitive phenomenon.  相似文献   
84.
Child care workers were trained in specified techniques (play manager routines) in an effort to increase purposeful activity among a group of profoundly and severely retarded institutionalized boys. A system of prompts, increasing the availability of toys and regular staff monitoring, were alternated with normal institutional routines in an ABA reversal design. On the average, activity level increased from 10% to a mean of 70% during treatment conditions. Correspondingly, stereotyped or harmful behaviors decreased from an average of 20% to 70% during treatment.  相似文献   
85.
86.
When disaster disrupts healthcare and other systems, the ethical allocation of resources should follow principles of justice, defined as fairness, established for normal clinical practice. Standards of clinical practice may be altered during disaster, but ethical standards must remain centered on prioritizing the treatment of patients according to need and the effectiveness of treatment. Should resources become extremely limited, it is fair to restrict their use to patients who have the highest needs, provided that the intervention is effective. When resources become more available, patients with lower priority can be increasingly accommodated.  相似文献   
87.
We evaluated various forms of hippocampus-dependent learning and memory, and hippocampal synaptic plasticity in THY-Tau22 transgenic mice, a murine tauopathy model that expresses double-mutated 4-repeat human tau, and shows neuropathological tau hyperphosphorylation and aggregation throughout the brain. Focussing on hippocampus, immunohistochemical studies in aged THY-Tau22 mice revealed prominent hyper- and abnormal phosphorylation of tau in CA1 region, and an increase in glial fibrillary acidic protein (GFAP) in hippocampus, but without signs of neuronal loss. These mice displayed spatial, social, and contextual learning and memory defects that could not be reduced to subtle neuromotor disability. The behavioral defects coincided with changes in hippocampal synaptic functioning and plasticity as measured in paired-pulse and novel long-term depression protocols. These results indicate that hippocampal tauopathy without neuronal cell loss can impair neural and behavioral plasticity, and further show that transgenic mice, such as the THY-Tau22 strain, might be useful for preclinical research on tauopathy pathogenesis and possible treatment.  相似文献   
88.
The demand for science trainees to have appropriate responsible conduct of research instruction continues to increase the attention shown by federal agencies and graduate school programs to the development of effective ethics curriculums. However, it is important to consider that the main learning environment for science graduate students and post-doctoral research fellows is within a laboratory setting. Here we discuss an internal laboratory program of weekly 15-minute ethics discussions implemented and used over the last 3 years in addition to the graduate school’s program of scientific integrity training. During this time, the environment and culture within our laboratory has changed to place greater emphasis on the ethical implications of our own research and the research we evaluate. We still struggle with how to accurately assess this behavioral change; although, we present preliminary survey results on the evaluation and impact of this style of curriculum for ethics instruction in our laboratory.  相似文献   
89.
This study examined the influence of protective factors on psychological distress and sleep among Year 12 students 1 month prior to their externally assessed examinations. The sample included 195 Year 12 students who were to sit for at least one examination. Students completed the Adolescent Resilience Questionnaire, a measure of subjective stress, the Depression Anxiety and Stress Scales – 21, and measures of sleep. A sizeable minority of students reported high levels of subjective stress, severe symptoms of depression, anxiety and stress, and very inadequate sleep. Freedom from negative cognitions was the factor most strongly associated with protection from psychological distress. None of the factors protected against inadequate sleep. Results showed few gender differences. The findings validate popular concern about the wellbeing of Year 12 students. They also confirm that protective factors do not provide equal protection for all individuals against all adverse outcomes.  相似文献   
90.
The consequences of the early onset of substance use on later outcomes are a public health concern. In the present study, we examined neighborhood risk factors as a possible predictor of the onset of substance use in adolescents. In addition, we assessed the potential buffering effects of parental supervision on the relationship between neighborhood risk and the onset of substance use. The participants included 95, abstinent, African American 6th graders (mean age = 11.5 years) who enrolled in one site of a national, multi-site study of high-risk youth participating in a federally sponsored program. In the 6th and 8th grades, the participants completed self-report measures regarding substance use, perceived negative neighborhood activities and parental supervision. Logistic regression analyses demonstrated that both exposure to negative neighborhood activities and low parental supervision increase the onset of substance use by the 8th grade among African American adolescents. However, the results suggested that parents can protect their adolescents from the impact of exposure to adverse neighborhood factors by providing appropriate supervision.  相似文献   
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