146 research outputs found

    Physiological responses to wearing the space shuttle launch and entry suit and the prototype advanced crew escape suit compared to the unsuited condition

    Get PDF
    The launch and entry suit (LES) is a life support suit worn during Orbiter ascent and descent. The impact of suit weight and restricted mobility on egress from the Orbiter during an emergency is unknown. An alternate suit - the advanced crew escape suite (ACES) - is being evaluated. The physiological responses to ambulatory exercise of six subjects wearing the LES and ACES were measured and compared to those measurements taken while unsuited. Dependent variables included heart rate and metabolic response to treadmill walking at 5.6 km/h (3.5 mph), and also bilateral concentric muscle strength about the knee, shoulder, and elbow. No significant (p greater than 0.06) differences in heart rate or metabolic variables were measured in either suit while walking at 5.6 km/h. Significant (p less than 0.05) decreases in all metabolic variables were remarked when both suits were compared to the unsuited condition. There were no significant (p greater than 0.05) differences among the three suit conditions at 30 or 180 deg/s for muscles about the elbow and knee; however, about the shoulder, a significant (p = 0.0215) difference between the ACES and the unsuited condition was noted. Therefore, wearing a life support suit while performing Orbiter egress imposes a significant metabolic demand on crewmembers. Selective upper body strength movements may be compromised

    Comparison of total body water estimates from O-18 and bioelectrical response prediction equations

    Get PDF
    Identification of an indirect, rapid means to measure total body water (TBW) during space flight may aid in quantifying hydration status and assist in countermeasure development. Bioelectrical response testing and hydrostatic weighing were performed on 27 subjects who ingested O-18, a naturally occurring isotope of oxygen, to measure true TBW. TBW estimates from three bioelectrical response prediction equations and fat-free mass (FFM) were compared to TBW measured from O-18. A repeated measures MANOVA with post-hoc Dunnett's Test indicated a significant (p less than 0.05) difference between TBW estimates from two of the three bioelectrical response prediction equations and O-18. TBW estimates from FFM and the Kushner & Schoeller (1986) equation yielded results that were similar to those given by O-18. Strong correlations existed between each prediction method and O-18; however, standard errors, identified through regression analyses, were higher for the bioelectrical response prediction equations compared to those derived from FFM. These findings suggest (1) the Kushner & Schoeller (1986) equation may provide a valid measure of TBW, (2) other TBW prediction equations need to be identified that have variability similar to that of FFM, and (3) bioelectrical estimates of TBW may prove valuable in quantifying hydration status during space flight

    Do Small, Patchy, Constructed Intertidal Oyster Reefs Reduce Salt Marsh Erosion As Well As Natural Reefs?

    Get PDF
    One ecological service that oyster reefs provide is stabilization of shorelines through reduced wave energy and erosion from boat traffic, storms, and predominant wind direction. Additionally, increasing sedimentation can enhance the growth of emergent marsh vegetation which further stabilizes unconsolidated sediments. A 21 mo study of constructed (with only 30-35% coverage) and natural oyster reefs in 3 bayous in the Grand Bay National Estuarine Research Reserve (NERR) suggested constructed reefs benefit this retrograding deltaic ecosystem. The marsh edge adjacent to all constructed reefs was less eroded (mean = 0.043 m) than edges adjacent to natural reefs (mean = 0.728 m), although all natural and constructed sites, regardless of bayou, illustrated large variations in marsh edge growth. The marsh edge in constructed sites in one bayou retreated more than in the other bayous, most likely due to its coarser sediments, greater boat traffic, and its apparent higher energy location within the landscape. By the end of this study, the ecological function of constructed oyster reefs in all bayous, as measured by marsh edge erosion reduction, was equivalent or exceeded the function in nearby natural oyster reefs. The physical structure of the reef further served to reduce erosion and marsh loss and this approach may be useful for management of a retrograding deltaic estuarine ecosystem like the Grand Bay NERR

    Characterization of Western Corn Rootworm (Coleoptera: Chrysomelidae) susceptibility to foliar insecticides in northeast Nebraska

    Get PDF
    Foliar-applied insecticides are commonly used for adult Western Corn Rootworm (WCR), Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), control in Nebraska but little efficacy data is available. Anecdotal reports of reduced efficacy in areas of northeast Nebraska led to the conduct of this study. Objectives were to (i) evaluate the efficacy of commercial applications of commonly used formulated insecticides (bifenthrin, lambda-cyhalothrin, chlorpyrifos, or tank mixes) for WCR control in 7 northeast Nebraska counties during 2019 and 2020 and (ii) conduct adult WCR concentration-response vial bioassays with bifenthrin, chlorpyrifos, and dimethoate active ingredients on a subset of field populations. Whole plant counts (WPC) were used to measure WCR densities in insecticide-treated and untreated maize fields before and after insecticide application. Field control was excellent with organophosphate/pyrethroid tank mixes as proportional change in mean WPC of treated fields was significantly reduced (\u3e0.90) versus untreated fields where little change in WPC occurred. The exception was one treated Boone County field where proportional reduction in WPC was ≤0.78. Bioassays revealed LC50s and resistance ratios of most populations exposed to bifenthrin and dimethoate were not significantly different than the susceptible control. Most populations exhibited a low level of chlorpyrifos resistance when compared to the susceptible control. Field and lab data suggest the local onset of practical WCR field-evolved resistance to bifenthrin in Boone County and chlorpyrifos in Boone and Colfax counties. Results of this study will increase our understanding of WCR resistance evolution, serve as a comprehensive baseline for future research, and inform WCR management programs

    Sensitive sexualities: dichotomized discourse in the erasure of bisexuality

    Get PDF
    A combination of Q methodology and a Think Aloud task explored how cultural knowledge about bisexuality is constructed and maintained. Q methodology revealed positive interpretations of bisexuality. Critical Discourse Analysis of the Think Aloud task however, exposed the maintenance of dualistic categories of sex, gender and sexuality acting as ‘operating systems’ and strategically guiding the social representation of bisexuality as ‘non-existent’, ‘deviant’, ‘abnormal’ and/or ‘promiscuous’. The findings of this study suggest that overt heterosexism is not becoming extinct; instead it has found rather subtle ways of incorporating itself into ‘liberal’ discourses

    Strategies for Strengthening the Resilience of Public Health Systems for Pandemics, Disasters, and Other Emergencies

    Get PDF
    OBJECTIVE: The aim of this study was to identify and prioritize strategies for strengthening public health system resilience for pandemics, disasters, and other emergencies using a scorecard approach. METHODS: The United Nations Public Health System Resilience Scorecard (Scorecard) was applied across 5 workshops in Slovenia, Turkey, and the United States of America. The workshops focused on participants reviewing and discussing 23 questions/indicators. A Likert type scale was used for scoring with zero being the lowest and 5 the highest. The workshop scores were analyzed and discussed by participants to prioritize areas of need and develop resilience strategies. Data from all workshops were aggregated, analyzed, and interpreted to develop priorities representative of participating locations. RESULTS: Eight themes emerged representing the need for better integration of public health and disaster management systems. These include: assessing community disease burden; embedding long-term recovery groups in emergency systems; exploring mental health care needs; examining ecosystem risks; evaluating reserve funds; identifying what crisis communication strategies worked well; providing non-medical services; and reviewing resilience of existing facilities, alternate care sites, and institutions. CONCLUSIONS: The Scorecard is an effective tool for establishing baseline resilience and prioritizing actions. The strategies identified reflect areas in most need for investment to improve public health system resilience
    • …
    corecore