72 research outputs found
Research on the International Space Station - An Overview
The International Space Station (ISS) celebrates ten years of operations in 2008. While the station did not support permanent human crews during the first two years of operations November 1998 to November 2000 it hosted a few early science experiments months before the first international crew took up residence. Since that time and simultaneous with the complicated task of ISS construction and overcoming impacts from the tragic Columbia accident science returns from the ISS have been growing at a steady pace. As of this writing, over 162 experiments have been operated on the ISS, supporting research for hundreds of ground-based investigators from the U.S. and international partners. This report summarizes the experimental results collected to date. Today, NASA's priorities for research aboard the ISS center on understanding human health during long-duration missions, researching effective countermeasures for long-duration crewmembers, and researching and testing new technologies that can be used for future exploration crews and spacecraft. Through the U.S. National Laboratory designation, the ISS is also a platform available to other government agencies. Research on ISS supports new understandings, methods or applications relevant to life on Earth, such as understanding effective protocols to protect against loss of bone density or better methods for producing stronger metal alloys. Experiment results have already been used in applications as diverse as the manufacture of solar cell and insulation materials for new spacecraft and the verification of complex numerical models for behavior of fluids in fuel tanks. A synoptic publication of these results will be forthcoming in 2009. At the 10-year point, the scientific returns from ISS should increase at a rapid pace. During the 2008 calendar year, the laboratory space and research facilities were tripled with the addition of ESA's Columbus and JAXA's Kibo scientific modules joining NASA's Destiny Laboratory. All three laboratories, together with external payload accommodations, support a wide variety of research racks and science and technology experiments. In 2009, the number of crewmembers will increase from three to six, greatly increasing the time available for research. The realization of the international scientific partnership provides new opportunities for scientific collaboration and broadens the research potential on the ISS. Engineers and scientists from around the world are working together to refine their operational relationships and build from their experiences conducting early science to ensure maximum utilization of the expanded capabilities aboard ISS. This paper will summarize science results and accomplishments, and discuss how the early science utilization provides the foundation for continuing research campaigns aboard the ISS that will benefit future exploration programs
What are we missing? Risk behaviors among Arabâ American adolescents and emerging adults
Background and purposeResearch on Arabâ Americans as a distinct ethnic group is limited, especially when considering the health of Arabâ American youth. This study describes health risk (substance use, violence); health promotive behaviors (hope, spirituality); and sexual activity (oral, vaginal, anal sex) of Arabâ American adolescents and emerging adults (aged 15â 23) within their life context, as well as the association between these behaviors.MethodsA secondary analysis of data on a subset of Arabâ American participants obtained from a randomizedâ control trial was utilized to conduct mixed methods analyses. Qualitative analyses completed on the openâ ended questions used the constant comparative method for a subsample (n = 24) of participants. Descriptive quantitative analyses of survey data utilized bivariate analyses and stepwise logistic regression to explore the relation between risk behaviors and sexual activity among the full sample (n = 57).ConclusionsQualitative analyses revealed two groups of participants: (a) multiple risk behaviors and negative lifeâ events, and (b) minimal risk behaviors and positive lifeâ events. Quantitative analyses indicated older youth, smokers, and those with higher hope pathways were more likely to report vaginal sex.Implications for practiceThe unique cultural and social contexts of Arabâ American youth provide a framework for recommendations for the prevention of risk behaviors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134166/1/jaan12352.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134166/2/jaan12352_am.pd
DISTRIBUTION AND PREVALENCE OF ELAEOPHORA SCHNEIDERI IN MOOSE IN WYOMING
Elaeophora schneideri causes disease in aberrant hosts such as moose. Documented E. schneideri infections in moose are relatively rare, yet noteworthy enough that individual cases describing morbidity and mortality have been the norm for reporting. Surveillance efforts for E. schneideri in Wyoming moose in the 1970s found zero cases, but since 2000 several moose in Wyoming discovered dead or showing clinical signs of elaeophorosis have been found infected with E. schneideri. In 2009 we searched for worms in the carotid arteries of 168 hunter-harvested moose from across Wyoming to determine the prevalence and distribution of E. schneideri in moose; 82 (48.8%; 95% CI: 41.4-56.3%) were positive for E. schneideri. Prevalence did not differ between sexes or among age classes but there was difference in prevalence among herd units (range = 5-82.6%). Intensity of infection (range = 1-26 worms) did not differ between sexes, among age classes, or among herd units. Our findings indicate that moose do not succumb to the parasite to the extent previously thought. Prevalence and intensity were constant across age classes, suggesting that infected moose are surviving and an acquired, immunological resistance to further infection develops. In addition, moose might sometimes act as natural hosts to the parasite, as indicated by 1) high prevalence of infection in moose in areas where sympatric mule deer had much lower prevalence of infection, and 2) preliminary necropsy findings that revealed microfilariae in skin samples from 3 moose. However, negative impacts to moose and moose populations cannot be ruled out entirely, as this study was limited to apparently healthy hunter-harvested animals. While moose appear to often survive infection with E. schneideri, prevalence of ~50% is still cause for concern because it is unknown to what extent this parasite causes subclinical effects in moose that might impact recruitment or productivity. Subsequent research on moose herds where E. schneideri occurs should consider the effects of elaeophorosis and attempt to clarify its role
Non-work-related services at the workplace : an exploratory study
In an era of diminishing public funds, the profession of social work is looking more and more toward the private sector as an arena for social work practice. Social work has had a long-standing interest in the impact of work and the workplace on the individual. This study was developed in response to the lack of documentation of non-work-related services in Oregon\u27s businesses and industries. The research team set out to discover what non-work-related services are available to employees at or through the workplace in the TriCounty area (Multnomah, Clackamas, and Washington Counties) of Oregon. This study was exploratory, similar to one done by Hans Spiegel and colleagues in 1974, through Hunter College in New York City
Ehrlichia ewingii Infection in White-Tailed Deer (Odocoileus virginianus)
Two closely related zoonotic ehrlichiae, Ehrlichia chaffeensis and E. ewingii, are transmitted by Amblyomma americanum, the lone star tick. Because white-tailed deer (Odocoileus virginianus) are critical hosts for all mobile stages of A. americanum and are important vertebrate reservoirs of E. chaffeensis, we investigated whether deer may be infected with E. ewingii, a cause of granulocytotropic ehrlichiosis in humans and dogs. To test for E. ewingii infection, we used polymerase chain reaction and inoculation of fawns with whole blood from wild deer. Of 110 deer tested from 20 locations in 8 U.S. states, 6 (5.5%) were positive for E. ewingii. In addition, natural E. ewingii infection was confirmed through infection of captive fawns. These findings expand the geographic distribution of E. ewingii, along with risk for human infection, to include areas of Kentucky, Georgia, and South Carolina. These data suggest that white-tailed deer may be an important reservoir for E. ewingii
Recommended from our members
HIV RNA, CD4+ Percentage, and Risk of Hepatocellular Carcinoma by Cirrhosis Status.
BackgroundDespite increasing incidence of hepatocellular carcinoma (HCC) among HIV-infected patients, it remains unclear if HIV-related factors contribute to development of HCC. We examined if higher or prolonged HIV viremia and lower CD4+ cell percentage were associated with HCC.MethodsWe conducted a cohort study of HIV-infected individuals who had HIV RNA, CD4+, and CD8+ cell counts and percentages assessed in the Veterans Aging Cohort Study (1999-2015). HCC was ascertained using Veterans Health Administration cancer registries and electronic records. Cox regression was used to determine hazard ratios (HR, 95% confidence interval [CI]) of HCC associated with higher current HIV RNA, longer duration of detectable HIV viremia (âĽ500 copies/mL), and current CD4+ cell percentage less than 14%, adjusting for traditional HCC risk factors. Analyses were stratified by previously validated diagnoses of cirrhosis prior to start of follow-up.ResultsAmong 35 659 HIV-infected patients, 302 (0.8%) developed HCC over 281 441 person-years (incidence rate = 107.3 per 100 000 person-years). Among patients without baseline cirrhosis, higher HIV RNA (HRâ=â1.25, 95% CIâ=â1.12 to 1.40, per 1.0 log10 copies/mL) and 12 or more months of detectable HIV (HRâ=â1.47, 95% CIâ=â1.02 to 2.11) were independently associated with higher risk of HCC. CD4+ percentage less than 14% was not associated with HCC in any model. Hepatitis C coinfection was a statistically significant predictor of HCC regardless of baseline cirrhosis status.ConclusionAmong HIV-infected patients without baseline cirrhosis, higher HIV RNA and longer duration of HIV viremia increased risk of HCC, independent of traditional HCC risk factors. This is the strongest evidence to date that HIV viremia contributes to risk of HCC in this group
Increased Risk of Fragility Fractures among HIV Infected Compared to Uninfected Male Veterans
BACKGROUND: HIV infection has been associated with an increased risk of fragility fracture. We explored whether or not this increased risk persisted in HIV infected and uninfected men when controlling for traditional fragility fracture risk factors. METHODOLOGY/PRINCIPAL FINDINGS: Cox regression models were used to assess the association of HIV infection with the risk for incident hip, vertebral, or upper arm fracture in male Veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC). We calculated adjusted hazard ratios comparing HIV status and controlling for demographics and other established risk factors. The sample consisted of 119,318 men, 33% of whom were HIV infected (34% aged 50 years or older at baseline, and 55% black or Hispanic). Median body mass index (BMI) was lower in HIV infected compared with uninfected men (25 vs. 28 kg/m²; p<0.0001). Unadjusted risk for fracture was higher among HIV infected compared with uninfected men [HR: 1.32 (95% CI: 1.20, 1.47)]. After adjusting for demographics, comorbid disease, smoking and alcohol abuse, HIV infection remained associated with an increased fracture risk [HR: 1.24 (95% CI: 1.11, 1.39)]. However, adjusting for BMI attenuated this association [HR: 1.10 (95% CI: 0.97, 1.25)]. The only HIV-specific factor associated with fragility fracture was current protease inhibitor use [HR: 1.41 (95% CI: 1.16, 1.70)]. CONCLUSIONS/SIGNIFICANCE: HIV infection is associated with fragility fracture risk. This risk is attenuated by BMI
Sex Disparities in Overall Burden of Disease Among HIV-Infected Individuals in the Veterans Affairs Healthcare System
Medical Intensive Care Unit Admission Among Patients With and Without HIV, Hepatitis C Virus, and Alcohol-Related Diagnoses in the United States: A National, Retrospective Cohort Study, 1997-2014.
BACKGROUND: HIV, hepatitis C virus (HCV), and alcohol-related diagnoses (ARD) independently contribute increased risk of all-cause hospitalization. We sought to determine annual medical intensive care unit (MICU) admission rates and relative risk of MICU admission between 1997 and 2014 among people with and without HIV, HCV, and ARD, using data from the largest HIV and HCV care provider in the United States. SETTING: Veterans Health Administration. METHODS: Annual MICU admission rates were calculated among 155,550 patients in the Veterans Aging Cohort Study by HIV, HCV, and ARD status. Adjusted rate ratios and 95% confidence intervals (CIs) were estimated with Poisson regression. Significance of trends in age-adjusted admission rates were tested with generalized linear regression. Models were stratified by calendar period to identify shifts in MICU admission risk over time. RESULTS: Compared to HIV-/HCV-/ARD- patients, relative risk of MICU admission decreased among HIV-mono-infected patients from 61% (95% CI: 1.56 to 1.65) in 1997-2009% to 21% (95% CI: 1.16 to 1.27) in 2010-2014, increased among HCV-mono-infected patients from 22% (95% CI: 1.16 to 1.29) in 1997-2009% to 54% (95% CI: 1.43 to 1.67) in 2010-2014, and remained consistent among patients with ARD only at 46% (95% CI: 1.42 to 1.50). MICU admission rates decreased by 48% among HCV-uninfected patients (P-trend <0.0001) but did not change among HCV+ patients (P-trend = 0.34). CONCLUSION: HCV infection and ARD remain key contributors to MICU admission risk. The impact of each of these conditions could be mitigated with combination of treatment of HIV, HCV, and interventions targeting unhealthy alcohol use
Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.
Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential
- âŚ