3,298 research outputs found

    A study of the effects of micro-gravity on seed germination

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    This study will identify characteristics of seed germination dependent upon gravity. To accomplish this objective, four different seed types will be germinated in space and then be compared to a control group germinated on Earth. Both the experimental and control groups will be analyzed on the cellular level for the size of cells, structural anomalies, and gravitational effects. The experiment will be conducted in a Get Away Special Canister (GAS Can no. 608) owned by the U.S. Space and Rocket Center and designed for students. The GAS Can will remain in the cargo bay of the Space Shuttle with minimal astronaut interaction

    Interdisciplinary Collaboration Needed in Obtaining High-Quality Medical Information in Child Abuse Investigations

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    Background Despite reporting legislation, healthcare providers (HCPs) do not always report and collaborate in cases of suspected child abuse. Recognizing this leaves children at risk, the Wisconsin Child Abuse Network (WI CAN) sought to understand barriers to mandated reporting and collaboration with child abuse investigators. Objective The purpose of the study was to investigate barriers for professionals in providing and obtaining high-quality medical information in child abuse investigations. Participants and setting Participants included five discipline-specific focus groups: HCPs, child protective services (CPS), law enforcement, lawyers, and judges. All professionals had been directly involved in Wisconsin child abuse cases. Methods This qualitative study consisted of discipline-specific focus groups, directed by open-ended interview questions. Data analysis was completed through the narrative inquiry methodology. Results Barriers to providing and obtaining high-quality medical information in child abuse investigations were both discipline-specific and universal amongst all groups. Discipline-specific barriers included: HCPs’ discomfort with uncertainty; CPS’ perception of disrespect and mistrust by HCPs; law enforcement’s concerns with HCPs’ overstepping professional boundaries; lawyers’ concern of HCPs’ discomfort with court proceedings; and judges’ perception of a lack of understanding between all disciplines. Universal barriers included: value of high-quality medical information in child abuse investigations, burden of time and money; unequal resources between counties; a need for protocols, and a need for interdisciplinary collaboration. Conclusion Findings from this study suggest several ways to address identified barriers. Possible interventions include equalizing resources between urban and rural counties (specifically financial resources and access to child abuse experts); protocolizing reporting and investigations; and, increasing interprofessional education

    Tantalum oxide coatings as candidate environmental barriers

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    Tantalum (Ta) oxide, due to its high-temperature capabilities and thermal expansion coefficient similar to silicon nitride, is a promising candidate for environmental barriers for silicon (Si) nitride-based ceramics. This paper focuses on the development of plasma-sprayed Ta oxide as an environmental barrier coating for silicon nitride. Using a D-optimal design of experiments, plasma-spray processing variables were optimized to maximize coating density. The effect of processing variables on coating thickness was also determined. X-ray diffraction (XRD) was use to ascertain that the as-sprayed coatings were comprised of α- and ÎČ-Ta2O5, but were fully converted to ÎČ-Ta_2O_5 after a 1200 °C heat treatment. Grain growth of the Ta_2O_5 followed a time dependence of t^(0.2) at 1200 °C

    Common Eider (Somateria mollissima v-nigrum) Nest Cover and Depredation on Central Alaskan Beaufort Sea Barrier Islands

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    Female common eiders (Somateria mollissima v-nigrum) generally select nest sites in areas with driftwood cover. Previous studies of common eiders have shown a positive relationship between nest success and driftwood cover. Our observations led us to hypothesize that cover does not enhance nest success when mammalian predators are present. To evaluate nest cover selection in common eiders, we examined five years of nesting data to determine the interactions between the probability of nest activity and the amount of driftwood cover in the presence of avian versus mammalian predators. Most common eider nests were surrounded by low (40%) or moderate (38%) driftwood cover. Nest failure rates were high (32%– 95%), and arctic foxes (Alopex lagopus), alone or with polar bears (Ursus maritimus), appeared to be more destructive than glaucous gulls (Larus hyperboreus) to eider nests. Logistic regression was used to model common eider nest activity associated with driftwood cover and predators. When glaucous gulls were the only predators, more driftwood cover consistently increased the probability of nest activity. But when foxes were present, nest activity consistently decreased with increasing cover. Our models support our observations that nest cover was beneficial to eiders when glaucous gulls alone were predators. Driftwood cover may be most important for the thermal and structural protection it offers, rather than for the camouflage it provides. The energetic benefit provided by driftwood windbreaks coupled with the common eider’s behavioral response of decreased nest attendance, or increased exposure to avian depredation of nests as energy reserves are depleted during incubation, provides an explanatory mechanism for our model results.L’eider Ă  duvet femelle (Somateria mollissima v-nigrum) choisit en gĂ©nĂ©ral son site de nidification dans des zones ayant un couvert de bois flottĂ©. Des Ă©tudes prĂ©cĂ©dentes sur les eiders Ă  duvet ont rĂ©vĂ©lĂ© qu’il existe une relation positive entre le succĂšs de la couvĂ©e et le couvert de bois flottĂ©. Nos observations nous ont amenĂ©s Ă  Ă©mettre l’hypothĂšse que le couvert n’augmente pas le succĂšs de la couvĂ©e en prĂ©sence de prĂ©dateurs mammifĂšres. Afin d’évaluer le choix de couvert du nid chez l’eider Ă  duvet, nous avons examinĂ© des donnĂ©es de nidification obtenues sur cinq annĂ©es, en vue de dĂ©gager les interactions entre la probabilitĂ© d’activitĂ© au nid et la quantitĂ© de couvert de bois flottĂ© en prĂ©sence de prĂ©dateurs aviens par opposition aux prĂ©dateurs mammifĂšres. La plupart des nids de l’eider Ă  duvet Ă©taient entourĂ©s par un faible couvert de bois flottĂ© (40 %) ou un couvert modĂ©rĂ© (38 %). Les taux d’insuccĂšs Ă©taient Ă©levĂ©s (32 Ă  95 %) et le renard arctique (Alopex lagopus), seul ou avec l’ours polaire (Ursus maritimus), semblait plus destructeur pour les nids de l’eider que le goĂ©land bourgmestre (Larus hyperboreus). On a utilisĂ© la rĂ©gression logistique pour simuler l’activitĂ© au nid de l’eider Ă  duvet associĂ©e au couvert de bois flottĂ© et aux prĂ©dateurs. Quand le goĂ©land bourgmestre Ă©tait le seul prĂ©dateur, une plus grande quantitĂ© de bois flottĂ© augmentait toujours la probabilitĂ© d’activitĂ© au nid. En revanche, en prĂ©sence du renard, l’activitĂ© au nid diminuait toujours avec une augmentation du couvert. Nos modĂšles viennent appuyer nos observations Ă  l’effet que le couvert du nid reprĂ©sentait un avantage pour l’eider quand le goĂ©land bourgmestre Ă©tait le seul prĂ©dateur. Le couvert de bois flottĂ© pourrait bien ĂȘtre d’une importance capitale en raison de la protection thermique et structurale qu’il offre, plutĂŽt que pour ses capacitĂ©s de camouflage. L’avantage Ă©nergĂ©tique qu’offrent les brise-vent de bois flottĂ© joint Ă  la rĂ©action comportementale de l’eider Ă  duvet – qui se manifeste par une plus grande prĂ©sence au nid, ou une plus grande exposition Ă  une dĂ©prĂ©dation avienne du nid Ă  mesure que s’épuisent les rĂ©serves d’énergie durant l’incubation –, ces deux Ă©lĂ©ments donc fournissent un mĂ©canisme pouvant expliquer les rĂ©sultats de notre modĂšle

    Long-Term Exposure to an Invasive Fungal Pathogen Decreases Eptesicus fuscus Body Mass With Increasing Latitude

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    Abstract Invasive pathogens threaten wildlife health and biodiversity. Physiological responses of species highly susceptible to pathogen infections following invasion are well described. However, the responses of less susceptible species (relative to highly susceptible species) are not well known. Latitudinal gradients, which can influence body condition via Bergmann\u27s rule and/or reflect the time it takes for an introduced pathogen to spread geographically, add an additional layer for how mammalian species respond to pathogen exposure. Our goal was to understand how hosts less susceptible to pathogen infections respond to long‐term pathogen exposure across a broad latitudinal gradient. We examined changes in body mass throughout pathogen exposure time across the eastern United States (latitude ranging 30.5° N–44.8° N) in Eptesicus fuscus, a bat species classified as less susceptible to infection (relative to highly susceptible species) by the invasive fungal pathogen that causes white‐nose syndrome, Pseudogymnoascus destructans (Pd). Using 30 years of spring through fall adult capture records, we created linear mixed‐effects models for female and male bats to determine how mass or mass variation changed across the eastern United States from pre‐Pd invasion years through Pd invasion (0–1 years with Pd), epidemic (2–4 years with Pd), and established years (5+ years with Pd). By Pd establishment, all female and male bats decreased body mass with increasing latitude across a spatial threshold at 39.6° N. Differences in bat mass north and south of the spatial threshold progressively increased over Pd exposure time‐steps such that body mass was lower in northern latitudes compared to southern latitudes by Pd establishment. Results indicated that the progressive differences in E. fuscus body mass with latitude across the eastern United States are due to long‐term pathogen exposure; however, other environmental and ecological pressures may contribute to decreases in E. fuscus body mass with latitude and long‐term pathogen exposure. As pathogen introductions and emerging infectious diseases become more prevalent on the landscape, it is imperative that we understand how less susceptible species directly and indirectly respond to long‐term pathogen exposure in order to maintain population health in surviving species

    Surveillance of congenital Zika syndrome in England and Wales: methods and results of laboratory, obstetric and paediatric surveillance.

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    The spread of the Zika virus (ZIKV) in the Americas led to large outbreaks across the region and most of the Southern hemisphere. Of greatest concern were complications following acute infection during pregnancy. At the beginning of the outbreak, the risk to unborn babies and their clinical presentation was unclear. This report describes the methods and results of the UK surveillance response to assess the risk of ZIKV to children born to returning travellers. Established surveillance systems operating within the UK - the paediatric and obstetric surveillance units for rare diseases, and national laboratory monitoring - enabled rapid assessment of this emerging public health threat. A combined total of 11 women experiencing adverse pregnancy outcomes after possible ZIKV exposure were reported by the three surveillance systems; five miscarriages, two intrauterine deaths and four children with clinical presentations potentially associated with ZIKV infection. Sixteen women were diagnosed with ZIKV during pregnancy in the UK. Amongst the offspring of these women, there was unequivocal laboratory evidence of infection in only one child. In the UK, the number and risk of congenital ZIKV infection for travellers returning from ZIKV-affected countries is very small

    Complete Spontaneous Regression of Pulmonary Metastatic Melanoma

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    Complete spontaneous regression of melanoma metastatic to the lungs is a rare event. objective . To report a case of biopsy-proven melanoma metastatic to the lung with complete spontaneous regression. methods . Multidisciplinary case report. results . A 35-year-old white female was diagnosed with metastatic melanoma to the lung. A pleural biopsy confirmed the diagnosis. Partial spontaneous regression was noted by a staging computed tomography scan prior to enrollment in an investiga-tional protocol. Complete spontaneous regression occurred over 5 months without any form of conventional or alternative therapy, and the patient remains disease-free 3 years after diagnosis. conclusions . Our case represents the seventh case of complete spontaneous regression of melanoma metastatic to the lung, and the only case with histologic confirmation of both the primary and pulmonary metastatic lesions. The patient was pregnant twice between the time of her initial diagnosis of primary melanoma and pulmonary metastatic disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75559/1/j.1524-4725.1998.tb04275.x.pd
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