1,733 research outputs found
Experimenting with Cigarettes and Physical Activity Among Mexican Origin Youth: A Cross Sectional Analysis of the Interdependent Associations Among Sensation Seeking, Acculturation, and Gender
Sensation seeking tendencies tend to manifest during adolescence and are associated with both health-compromising behaviors and health-enhancing behaviors. The purpose of this study is to evaluate the relationship between sensation seeking and physical activity, a health-enhancing behavior, and between sensation seeking and experimenting with cigarettes, a health compromising-behavior, among a cohort of Mexican origin adolescents residing in the United States with different levels of acculturation. Methods: In 2009, 1,154 Mexican origin youth (50.5% girls, mean age 14.3 years (SD = 1.04)) provided data on smoking behavior, physical activity, linguistic acculturation, and sensation seeking. We conducted Pearson's chi(2) tests to examine the associations between categorical demographic characteristics (i.e. gender, age, country of birth and parental educational attainment) and both cigarette experimentation and physical activity and Student's t-tests to examine mean differences on the continuous variables (i.e. sensation seeking subscale) by the behaviors. We examined mean differences in the demographic characteristics, acculturation, and both behaviors for each of the sensation seeking subscales using analysis of variance (ANOVA). To examine relationships between the sensation seeking subscales, gender, and both behaviors, at different levels of acculturation we completed unconditional logistic regression analyses stratified by level of acculturation. Results: Overall, 23.3% had experimented with cigarettes and 29.0% reported being physically active for at least 60 minutes/day on at least 5 days/week. Experimenting with cigarettes and being physically active were more prevalent among boys than girls. Among girls, higher levels of sensation seeking tendencies were associated with higher levels of acculturation and experimentation with cigarettes, but not with physical activity. Among boys, higher levels of sensation seeking tendencies were associated with higher levels of acculturation, experimenting with cigarettes and being physically active. Conclusions: Our results suggest that interventions designed to prevent smoking among Mexican origin youth may need to address social aspects associated with acculturation, paying close attention to gendered manifestations of sensation seeking.National Cancer Institute CA105203, CA126988Caroline W. Law Fund for Cancer PreventionDan Duncan Family Institute for Cancer Prevention and Risk AssessmentCenter for Health Promotion and Disease Prevention Research in Underserved Population
Are variations in rates of attending cultural activities associated with population health in the United States?
<p>Abstract</p> <p>Background</p> <p>Population studies conducted in Sweden have revealed an association between attendance at cultural activities and health. Using data from US residents, we examined whether the association could be observed in the US.</p> <p>Methods</p> <p>Participants in the current study included 1,244 individuals who participated in the 1998 General Social Survey.</p> <p>Results</p> <p>A significant association between cultural activities and self-reported health (SRH) was observed, even after controlling for age, gender, marital status, race, number of children, subjective social class, employment status, household income, and educational attainment. Specifically, the more cultural activities people reported attending, the better was their SRH.</p> <p>Conclusion</p> <p>The data confirm that an association between cultural activity and health is present in a US sample. The data do not mean that the association is causal, but they suggest that further longitudinal research is warranted.</p
The uptake of new knee replacement implants in the UK:Analysis of the National Joint Registry for England and Wales
Effect of substrate proximity on luminescence yield from Si nanocrystals
The influence of the proximity of a high refractive index substrate on the luminescence of Si nanocrystals was investigated by time-integrated and time-resolved photoluminescence. The luminescence yield was found to be ∼2.5 times larger for emitters distanced from the substrate compared to those in proximity with the substrate, while luminescence decay measurements revealed only a slight increase in the luminescence lifetime (∼15%). Results are discussed in terms of local density of optical modes surrounding a pointlike light emitter with important implications for the collection efficiency of luminescence and the estimation of internal quantum efficiency for a quantum dot.Support for this work was provided by
the Swedish Research Council VR and the Australian Research
Council ARC
Lightweight Bulldozer Attachment for Construction and Excavation on the Lunar Surface
A lightweight bulldozer blade prototype has been designed and built to be used as an excavation implement in conjunction with the NASA Chariot lunar mobility platform prototype. The combined system was then used in a variety of field tests in order to characterize structural loads, excavation performance and learn about the operational behavior of lunar excavation in geotechnical lunar simulants. The purpose of this effort was to evaluate the feasibility of lunar excavation for site preparation at a planned NASA lunar outpost. Once the feasibility has been determined then the technology will become available as a candidate element in the NASA Lunar Surface Systems Architecture. In addition to NASA experimental testing of the LANCE blade, NASA engineers completed analytical work on the expected draft forces using classical soil mechanics methods. The Colorado School of Mines (CSM) team utilized finite element analysis (FEA) to study the interaction between the cutting edge of the LANCE blade and the surface of soil. FEA was also used to examine various load cases and their effect on the lightweight structure of the LANCE blade. Overall it has been determined that a lunar bulldozer blade is a viable technology for lunar outpost site preparation, but further work is required to characterize the behavior in 1/6th G and actual lunar regolith in a vacuum lunar environment
Comparison of ISRU Excavation System Model Blade Force Methodology and Experimental Results
An Excavation System Model has been written to simulate the collection and transportation of regolith on the Moon. The calculations in this model include an estimation of the forces on the digging tool as a result of excavation into the regolith. Verification testing has been performed and the forces recorded from this testing were compared to the calculated theoretical data. A prototype lunar vehicle built at the NASA Johnson Space Center (JSC) was tested with a bulldozer type blade developed at the NASA Kennedy Space Center (KSC) attached to the front. This is the initial correlation of actual field test data to the blade forces calculated by the Excavation System Model and the test data followed similar trends with the predicted values. This testing occurred in soils developed at the NASA Glenn Research Center (GRC) which are a mixture of different types of sands and whose soil properties have been well characterized. Three separate analytical models are compared to the test data
HIV-Associated Mycobacterium tuberculosis Bloodstream Infection Is Underdiagnosed by Single Blood Culture
ABSTRACT
We assessed the additional diagnostic yield for
Mycobacterium tuberculosis
bloodstream infection (BSI) by doing more than one tuberculosis (TB) blood culture from HIV-infected inpatients. In a retrospective analysis of two cohorts based in Cape Town, South Africa, 72/99 (73%) patients with
M. tuberculosis
BSI were identified by the first of two blood cultures during the same admission, with 27/99 (27%; 95% confidence interval [CI], 18 to 36%) testing negative on the first culture but positive on the second. In a prospective evaluation of up to 6 blood cultures over 24 h, 9 of 14 (65%) patients with
M. tuberculosis
BSI had
M. tuberculosis
grow on their first blood culture; 3 more patients (21%) were identified by a second independent blood culture at the same time point, and the remaining 2 were diagnosed only on the 4th and 6th blood cultures. Additional blood cultures increase the yield for
M. tuberculosis
BSI, similar to what is reported for nonmycobacterial BSI.
</jats:p
Impulsive choice in mice lacking paternal expression of Grb10 suggests intragenomic conflict in behavior
Imprinted genes are expressed from one parental allele only as a consequence of epigenetic events that take place in the mammalian germ line and are thought to have evolved through intra-genomic conflict between parental alleles. We demonstrate, for the first time, oppositional effects of imprinted genes on brain and behavior. Specifically, here we show that mice lacking paternal Grb10 make fewer impulsive choices, with no dissociable effects on a separate measure of impulsive action. Taken together with previous work showing that mice lacking maternal Nesp55 make more impulsive choices this suggests that impulsive choice behavior is a substrate for the action of genomic imprinting. Moreover, the contrasting effect of these two genes suggests impulsive choices are subject to intra-genomic conflict and that maternal and paternal interests pull this behavior in opposite directions. Finally, these data may also indicate that an imbalance in expression of imprinted genes contributes to pathological conditions such as gambling and drug addiction, where impulsive behavior becomes maladaptive
- …