35 research outputs found

    A Comparison of Techniques for the Integration of Satellite Altimeter and Surface Gravity Data for Geoid Determination

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    Two methods are tested whereby satellite altimeter measurements of the geoid height are combined with surface measurements of the free-air gravity anomaly. The study area comprises the oceans around the Australian continent. The first method involves draping a grid of the free-air anomaly from satellite data onto a grid of the ship and land data. The second method utilises grids of the altimeter-derived geoid height, combining these with the surface data in an iterative superposition. Preliminary results show that the draping method yields a fit of 5.4 mGal between the satellite and marine data, while the iterative procedure returns 8.1 mGal. Further work can be done, however, to improve these results. The impact of the combined marine gravity data sets is illustrated by comparing the effects on an Australia-wide spherical-FFT geoid solution

    Measuring promotors of school functioning: Informing school-based psychosocial support for crisis-affected students in Lebanon

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    The evolving situation in Lebanon is characterized by multiple crises that affect education and can negatively affect a student’s school-functioning and mental health. The Ministry of Education and Higher Education decided in 2019 to further intensify and upscale implementation of school-based psychosocial support. This study is a contextualization and validation of the Student Learning in Emergencies Checklist for use in Lebanon. A 27-item questionnaire was proposed and tested to explore categories for measuring the effect of psychosocial support on academic functioning and academic performance and build evidence for program design. Promotors for school functioning were also explored. The participants (N = 1048) were divided between Lebanese students (N = 573) and non-Lebanese students (N = 520) with a mean age of 11.77 and gender balance. Multiple regression analysis demonstrated that the combined proposed categories explained 33.7% of the variance of school functioning as opposed to other factors. The new categories for safety and support at school and safety and support at home were found to predict academic functioning alone. Lebanese students reported significantly reduced scores in safety and support at school compared to non-Lebanese students. The need for psychosocial and educational support increased significantly with age, and males reported lower scores than females. Content and strategies for school-based psychosocial support for students are discussed

    Nociceptin Signals Through Calcium in \u3ci\u3eTetrahymena thermophila\u3c/i\u3e

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    Tetrahymena thermophila are free-living, ciliated, eukaryotic organisms that respond to stimuli by moving toward chemoattractants and avoiding chemorepellents. Chemoattractant responses involve faster ciliary beating, which propels the organisms forward more rapidly. Chemorepellents signaling involves ciliary reversal, which disrupts forward swimming, and causes the organisms to jerk back and forth, swim in small circles, or spin in an attempt to get away from the repellent. Many food sources, such as proteins, are chemoattractants for these organisms, while a variety of compounds are repellents. Repellents in nature are thought to come from the secretions of predators, or from ruptured organisms, which may serve as danger signals. Interestingly, several hormones involved in human pain signaling have been shown to be chemorepellents in Tetrahymena, including substance P, ACTH, PACAP, VIP, and nociceptin. Recently, we have been studying Tetrahymena response to nociceptin, using pharmacological inhibitors in order to elucidate components of the nociceptin signaling pathway. We have found that G-protein inhibitors and a number of mammalian tyrosine kinase inhibitors have no effect on nociceptin avoidance. However, the tyrosine kinase inhibitor, genistein, inhibits avoidance to nociceptin. Nociceptin avoidance is also inhibited by the calcium chelator, EGTA, which implicates calcium in the avoidance response. Electrophysiology studies done in a calcium-containing buffer show that 50 μM nociceptin causes a sustained depolarization of approximately 30 mV, further supporting the hypothesis that calcium is involved in nociceptin signaling. J-113397, an inhibitor of the human nociceptin receptor, also inhibits nociceptin avoidance in Tetrahymena. We are currently working to determine whether other inhibitors of the human nociceptin receptor have any effect on Tetrahymena, in order to get a more complete picture of the signaling pathway

    Manganese superoxide dismutase Ala-9Val polymorphism and risk of breast cancer in a population-based case–control study of African Americans and whites

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    INTRODUCTION: A polymorphism in the manganese superoxide dismutase (MnSOD) gene, Ala-9Val, has been examined in association with breast cancer risk in several epidemiologic studies. Results suggest that the Ala allele increases the risk of breast cancer and modifies the effects of environmental exposures that produce oxidative damage to DNA. METHODS: We examined the role of the MnSOD Ala-9Val polymorphism in a population-based case–control study of invasive and in situ breast cancer in North Carolina. Genotypes were evaluated for 2025 cases (760 African Americans and 1265 whites) and for 1812 controls (677 African Americans and 1135 whites). RESULTS: The odds ratio for MnSOD Ala/Ala versus any MnSOD Val genotypes was not elevated in African Americans (odds ratio = 0.9, 95% confidence interval = 0.7–1.2) or in whites (odds ratio = 1.0, 95% confidence interval = 0.8–1.2). Greater than additive joint effects were observed for the Ala/Ala genotype and smoking, radiation to the chest, and occupational exposure to ionizing radiation. Antagonism was observed between the Ala/Ala genotype and the use of nonsteroidal anti-inflammatory drugs. CONCLUSIONS: The MnSOD genotype may contribute to an increased risk of breast cancer in the presence of specific environmental exposures. These results provide further evidence for the importance of reactive oxygen species and of oxidative DNA damage in the etiology of breast cancer

    Macroalgae as spatial and temporal bioindicators of coastal metal pollution following remediation and diversion of acid mine drainage

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    © 2019 Elsevier Inc. Acid mine drainage (AMD) is a significant contributor of metal pollution leading to ecosystem damage. Bioindicator organisms such as intertidal brown macroalgae have an important role in quantifying the risks of metal bioaccumulation in coastal locations exposed to AMD contamination. Measurement of As, Cd, Cu, Fe, Pb, and Zn accumulation was performed in Fucus serratus, Fucus vesiculosus and Ascophyllum nodosum sampled from two marine locations near to an abandoned Cu mine in Anglesey, Wales, UK. Transect samples were taken from a coastal location (Amlwch) that has seen a substantial increase in AMD contamination over 15 years, in comparison to a nearby estuarine location (Dulas Estuary leading to Dulas Bay) with a historic legacy of pollution. These were compared with samples from the same sites taken 30 years earlier. Some of the Dulas macroalgae samples had Cd, Cu and Zn concentrations that were above background but in general indicated a non-polluted estuary in comparison to substantial pollution over previous decades. In contrast, Fucus samples collected from directly below an AMD outflow at Amlwch showed extremely elevated metal bioaccumulation (>250 mg Fe g−1, >6 mg Cu g−1, >2 mg Zn g−1, >190 μg As g−1) and evidence of macroalgae toxicity, indicating severe pollution at this site. However, the pollution dispersed within 200 m of the outflow source. This study has demonstrated the efficiency of three brown macroalgae species as indicators for metal bioavailability at high spatial resolution and over time

    Cold atoms in space: community workshop summary and proposed road-map

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    We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies

    Cold atoms in space: community workshop summary and proposed road-map

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    We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.publishedVersio

    Development and Psychometric Testing of the Student Learning in Emergencies Checklist (SLEC): Measuring Promotors of Academic Functioning and Wellbeing in Palestinian Youth Affected by War and Conflict

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    Youth living with war and ongoing conflict are frequently exposed to potentially traumatic events and cumulative stress which can result in temporarily impaired academic functioning and reduced wellbeing in school. In Palestine, the Ministry of Education has included psychosocial support programmes in the schools for the purpose of reducing stress reactions and improving school functioning amongst students. The Student Learning in Emergencies Checklist (SLEC) was developed in a psychometric testing study for monitoring and evaluating school-based psychosocial support in the Palestinian context—self-perceived academic functioning and wellbeing in particular. The study included 789 Palestinian students (12–16 years of age) living in Gaza, the West Bank and East Jerusalem, using an instrument that monitors five theoretical constructs considered to promote school functioning in emergencies. The analysis revealed a different factor structure than hypothesised: 1) safety and adaptability, 2) emotion regulation, 3) school support, 4) family support and 5) wellbeing and hope. The SLEC satisfies monitoring and evaluation purposes for fieldwork regarding programme planning, design and evaluation. Further, it appears well-suited for use by teachers for raising awareness of the need for and guiding their delivery of psychosocial support. The present study discusses practical implications and limitations of the SLEC
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