3,177 research outputs found

    Mule deer movements, survival, and use of contaminated areas at Rocky Flats, Colorado

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    Department Head: Robert Sewell Cook.Includes bibliographical references (pages 55-58).Rocky Mountain mule deer (Odocoileus hemionus hemionus) reside on plutonium contaminated land that surrounds the Rocky Flats Nuclear Weapons Facility, Colorado. Concern exists over the potential for deer to transport radionuclides away from Rocky Flats. Deer may potentially transport radionuclides through excretion of contaminated forage and soil away from the ingestion site, or by retention of radionuclides in tissues or the hide. To assess their potential to transport radionulcides and to determine annual movement patterns, deer were radio-located throughout the year. Rocky Flats deer were year-round residents, seldom moved farther than 0.05 km from the buffer zone boundaries. At least 9 male yearlings left Rocky Flats, and yearlings are, therefore, the most likely age class for radionuclide transport. Based on annual movement patterns I observed, the potential for does and fawns to transport radionuclides off-site appears to be very low, although more data are needed to better assess movement patterns of yearlings. Two areas in the buffer zone contain detectable levels of radionuclides and are accessible to deer. I compared deer use to availability in these areas during winter and summer 1991. During winter, 45.3% and 52.0% of radio-collared does and fawns showed preference (P ≤ 0.027) for these 2 areas over non-contaminated areas. During summer, 39.0% and 36.7% of deer preferred (P ≤ 0.027) each area to non-contaminated areas. I also collected tissue samples from 7 vehicle-killed deer that were known to inhabit the buffer zone and submitted them for radionuclide analysis. All tissues had plutonium activities below detection limits. Again, transport of radionuclides appears to be very low, but because of small sample size, any conclusion regarding plutonium transport is premature. The deer population size was estimated from a helicopter survey during summer 1990, and from a ground survey during winter 1991. Population estimates were 161 (95% confidence interval 136-220) during summer, and 199 (95% confidence interval 198-207) during winter. Winter 1991 buck:doe ratio was 35:100, and fawn:doe ratio was 90:100. Annual adult doe survival rates were 0.792 ± 0.083 (SE) in 1990 (n = 24), and 0.857 ± 0.059 (SE) in 1991 (n = 35), and were not statistically different (P = 0.19). Winter survival rate for female fawns was 0.895 ± 0.043 (SE) (n=19), and male fawn survival rate for the same time period was 0.950 ± 0.046 (SE) (n=21), and did not differ statistically (P = 0.51). The major cause of mortality among radio-collared deer was collisions with vehicles (47.8%), and predation (21.8%). Accidents and unknown causes comprised the remainder of mortalities (30.4%)

    Evaluation of advanced combustion concepts for dry NO sub x suppression with coal-derived, gaseous fuels

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    The emissions performance of a rich lean combustor (developed for liquid fuels) was determined for combustion of simulated coal gases ranging in heating value from 167 to 244 Btu/scf (7.0 to 10.3 MJ/NCM). The 244 Btu/scf gas is typical of the product gas from an oxygen blown gasifier, while the 167 Btu/scf gas is similar to that from an air blown gasifier. NOx performance of the rich lean combustor did not meet program goals with the 244 Btu/scf gas because of high thermal NOx, similar to levels expected from conventional lean burning combustors. The NOx emissions are attributed to inadequate fuel air mixing in the rich stage resulting from the design of the large central fuel nozzle delivering 71% of the total gas flow. NOx yield from ammonia injected into the fuel gas decreased rapidly with increasing ammonia level, and is projected to be less than 10% at NH3 levels of 0.5% or higher. NOx generation from NH3 is significant at ammonia concentrations significantly less than 0.5%. These levels may occur depending on fuel gas cleanup system design. CO emissions, combustion efficiency, smoke and other operational performance parameters were satisfactory. A test was completed with a catalytic combustor concept with petroleum distillate fuel. Reactor stage NOx emissions were low (1.4g NOx/kg fuel). CO emissions and combustion efficiency were satisfactory. Airflow split instabilities occurred which eventually led to test termination

    Anisotropy and controllable band structure in supra-wavelength polaritonic metasurfaces

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    In this letter we exploit the extended coherence length of mixed plasmon/exciton states to generate active metasurfaces. For this purpose, periodic stripes of organic dye are deposited on a continuous silver film. Typical metasurface effects, such as effective behavior and geometry sensitivity, are measured for periods exceeding the polaritonic wavelength by more than one order of magnitude. By adjusting the metasurface geometry, anisotropy, modified band structure and unidimensional polaritons are computationally simulated and experimentally observed in reflectometry as well as in emission.Comment: 4 figures, 1 Supplementary Material

    Late style and speaking out: J A Symonds's In the Key of Blue

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    This article examines In the Key of Blue (1893)—an essay collection by John Addington Symonds—as a case study in queer public utterance during the early 1890s. Viewed through the critical lens of late style, as theorised by Edward Said, the evolution of this project, from compilation through to reader reception, reveals Symonds's determination to “speak out” on the subject of homosexuality. Paradoxically, In the Key of Blue was thus a timely and untimely work: it belonged to a brief period of increased visibility and expressiveness when dealing with male same-sex desire, spearheaded by a younger generation of Decadent writers, but it also cut against the grain of nineteenth-century social taboo and legal repression. Symonds's essay collection brought together new and previously unpublished work with examples of his writing for the periodical press. These new combinations, appearing together for the first time, served to facilitate new readings and new inferences, bringing homosexual themes to the fore. This article traces the dialogic structure of In the Key of Blue , its strategies for articulating homosexual desire, and examines the response of reviewers, from the hostile to celebratory

    A Basic Study on Temporal Parameter Estimation of Wheelchair Propulsion based on Measurement of Upper Limb Movements Using Inertial Sensors

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    Wheelchairs are the most widely used assistive device to aid activities of daily living (ADL) for disabled people. However, manual pushing of a wheelchair frequently leads to overuse of upper extremities causing shoulder pain and carpal tunnel syndrome. The purpose of this study was to test a novel method of estimating temporal parameters of wheelchair propulsion using inertial sensors. In this paper, normalized coordinate values of the vector defined on the upper arm were calculated from an inertial sensor attached on the upper arm. The number of strokes and push cycle timings including duration of propulsion and recovery phases were estimated for steady state wheelchair propulsion. This estimation was completed using a novel vector-based approach and a previously published resultant acceleration method; both were compared to timings measured using the SmartWheel. Measurements were performed on level and sloped surfaces with 10 able bodied subjects. The vector-based method improved estimation of the number of strokes when compared to the resultant acceleration method. However, the push cycle was estimated with better accuracy by the resultant acceleration method. Therefore, a combination of the vector-based and the resultant acceleration methods is proposed to ensure more accurate estimation of temporal parameters. The results suggest inertial sensors can be used to measure wheelchair activity accurately and reliably

    A participatory process for modelling green infrastructure implementation in London

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    Cities face the interlinked challenges of transforming environmental quality, sustainability, population health and health equity. There is increasing interest in green infrastructure in connection with these challenges. In order to go beyond an understanding of the effects of green infrastructure and develop an understanding of how policymakers should think about it, we need to capture potential interactions and be aware of possible unintended consequences. In our research, we applied a systems-thinking approach: integrating participatory engagements, qualitative system dynamics modelling, and an assessment framework in order to address the challenge. This allowed us to see multiple dynamics between the prioritisation of policymakers, different types of green infrastructure, and environmental and health outcomes. It also made us ask different and more integrated questions, and suggested a methodology for addressing the challenge of transforming cities

    Burden of illness of trigeminal neuralgia among patients managed in a specialist center in England

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    BACKGROUND: Trigeminal neuralgia (TN) causes severe episodic, unilateral facial pain and is initially treated with antiepileptic medications. For patients not responding or intolerant to medications, surgery is an option. METHODS: In order to expand understanding of the pain-related burden of illness associated with TN, a cross-sectional survey was conducted of patients at a specialist center that utilizes a multidisciplinary care pathway. Participants provided information regarding their pain experience and treatment history, and completed several patient-reported outcome (PRO) measures. RESULTS: Of 129 respondents, 69/128 (54%; 1 missing) reported no pain in the past 4 weeks. However, 84 (65%) respondents were on medications, including 49 (38%) on monotherapy and 35 (27%) on polytherapy. A proportion of patients had discontinued at least one medication in the past, mostly due to lack of efficacy (n = 62, 48%) and side effects (n = 51, 40%). A total of 52 (40%) patients had undergone surgery, of whom 30 had microvascular decompression (MVD). Although surgery, especially MVD, provided satisfactory pain control in many patients, 29% of post-surgical patients reported complications, 19% had pain worsen or stay the same, 48% were still taking pain medications for TN, and 33% reported new and different facial pain. CONCLUSIONS: In most PRO measures, respondents with current pain interference had poorer scores than those without pain interference. In the Patient Global Impression of Change, 79% expressed improvement since beginning of treatment at this clinic. These results indicate that while the multidisciplinary approach can substantially alleviate the impact of TN, there remains an unmet medical need for additional treatment options

    Use of a saliva-based diagnostic test to identify tapeworm infection in horses in the UK

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    Background: Anthelmintic resistance combined with limited chemotherapeutic options has prompted a change in approaches to control of equine helminth infections. Targeted selective treatment strategies use diagnostics to reduce anthelmintic use by treating individuals with worm burdens or egg shedding levels above a set threshold. While faecal egg count analysis has limitations for informing tapeworm treatment, a commercially available saliva-based diagnostic test accurately diagnoses horses with tapeworm infection. Objectives: Evaluation of a saliva-based diagnostic test to identify horses naturally infected with tapeworm and assess the impact of using the test to inform anthelmintic administration. Study design: Retrospective longitudinal study. Methods: Saliva was collected from horses (n = 237) at a UK welfare charity from autumn 2015 to autumn 2016. Horses diagnosed as positive for tapeworm infection using the EquiSal® Tapeworm test were anthelmintic treated according to weight. The number of horses that received anthelmintic treatment based on the test result was compared with an all-group treatment approach and the reduction in anthelmintic usage calculated. Incoming horses were also tested (n = 143) and the information was used to inform quarantine treatments. Results: In autumn 2015, 85% of 237 horses tested received no anthelmintic and the majority (71%) of these remained below the treatment threshold throughout the study. Of the 69 horses that received treatment, seven required treatment following three subsequent tests, while >50% of horses administered with anthelmintic fell below the treatment threshold at the following test. No increase in tapeworm prevalence within the 237 horses was observed during the study despite a substantial reduction in the application of antitapeworm treatments. A total of 41% of incoming horses required anticestode treatment. Main limitations: Other management practices were not included in the analysis. Conclusions: Compared with an all-group treatment strategy, the diagnostic-led approach used here considerably reduced application of anticestode anthelmintics. This could reduce selection pressure for anthelmintic resistance

    Low temperature exposure induces browning of bone marrow stem cell derived adipocytes in vitro

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    Brown and beige adipocytes are characterised as expressing the unique mitochondrial uncoupling protein (UCP)1 for which the primary stimulus in vivo is cold exposure. The extent to which cold-induced UCP1 activation can also be achieved in vitro, and therefore perform a comparable cellular function, is unknown. We report an in vitro model to induce adipocyte browning using bone marrow (BM) derived mesenchymal stem cells (MSC), which relies on differentiation at 32 °C instead of 37 °C. The low temperature promoted browning in adipogenic cultures, with increased adipocyte differentiation and upregulation of adipogenic and thermogenic factors, especially UCP1. Cells exhibited enhanced uncoupled respiration and metabolic adaptation. Cold-exposed differentiated cells showed a marked translocation of leptin to adipocyte nuclei, suggesting a previously unknown role for leptin in the browning process. These results indicate that BM-MSC can be driven to forming beige-like adipocytes in vitro by exposure to a reduced temperature. This in vitro model will provide a powerful tool to elucidate the precise role of leptin and related hormones in hitherto functions in the browning process

    Developmental trajectories of emotional disengagement from schoolwork and their longitudinal associations in England

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    This study identified the varied ways in which emotional disengagement from schoolwork typically developed between 14 and 16 years of age, in the Longitudinal Study of Young People in England. Using growth mixture modelling we found eight main trajectories of (dis)engagement, with four trajectories of either increasing or stable emotional disengagement with schoolwork (41% of the sample). Using propensity score matching to create groups balanced on a wide range of covariates at Wave 1, we compared disengaged students to their engaged counterparts to identify the longitudinal effects of disengagement-trajectory membership on behavioural engagement, psychological wellbeing, substance use, career pathways and achievement. Using linear and binary logistic regressions, we established that students in disengagement trajectories developed lower achievement across compulsory secondary school, and participated less in education and more in employment at age 17 years. In young adulthood (age 19–20 years) they were less likely to attend university and more likely to be unemployed. During secondary schooling, they developed higher levels of substance use and poorer psychological wellbeing, which persisted in the year after compulsory school. However, in young adulthood, the differences in substance use dissipated and students in most of the disengagement trajectories had relatively similar life satisfaction to their counterparts. These findings suggest that students (except perhaps those who became unemployed) were able to develop healthily and happily after leaving the schoolwork environments from which they were emotionally disengaged
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