2,655 research outputs found

    The Law and Policy of Refugee Cities: Special Economic Zones for Migrants

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    Effect of implanted metal impurities on superconducting tungsten films

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    The superconducting transition temperature of more than 30 thin-film tungsten samples was measured using a dilution refrigerator. The samples were fabricated using a 99.999% pure tungsten target and a dc magnetron sputtering system. Individual films were then doped with metal impurity ions using an accurate ion implantation technique. The effect of the metal–ion doping on the superconducting transition temperature was measured for samples with superconducting transitions in the range of 40–150 mK. Magnetic dopant species including Ni, Co, and Fe resulted in suppressed values of the tungsten Tc. The suppression was linear with increasing dopant concentration, for concentrations up to tens of ppm. For higher concentrations of magnetic atoms, the data are consistent with the Abrikosov–Gor\u27kov theory [Soviet Physics JETP 12, 1243 (1961)] modified by antiferromagnetic impurity–impurity interactions. By contrast, tungsten films implanted with Mg or Cr showed little change in Tc after doping. In this article, we present data from cryogenic experiments on these films. We also present x-ray diffraction (XRD) spectra for a subset of the films. Our XRD data confirm that the observed suppression in Tc for the magnetically doped samples is not due to any structural changes (e.g., lattice distortion or damage) induced by the implantation process

    Mechanisms regulating angiogenesis underlie seasonal control of pituitary function

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    Seasonal changes in mammalian physiology, such as those affecting reproduction, hibernation and metabolism, are controlled by pituitary hormones released in response to annual environmental changes. In temperate zones, the primary environmental cue driving seasonal reproductive cycles is the change in daylength (photoperiod), encoded by the pattern of melatonin secretion from the pineal gland. However, although reproduction relies on hypothalamic gonadotrophin-releasing hormone (GnRH) output, and most cells producing reproductive hormones are in the pars distalis (PD) of the pituitary, melatonin receptors are localized in the pars tuberalis (PT), a physically and functionally separate part of the gland. How melatonin in the PT controls the PD is not understood. Here we show that melatonin time-dependently acts on its receptors in the PT to alter splicing of vascular endothelial growth factor (VEGF). Outside the breeding season, angiogenic VEGF-A stimulates vessel growth in the infundibulum, aiding vascular communication between the PT, PD and brain. This also acts on VEGFR2 expressed in PD prolactin-producing cells known to impair gonadotrophin secretion. In contrast, in the breeding season, melatonin releases anti-angiogenic VEGF-Axxxb from the PT, inhibiting infundibular angiogenesis and diminishing lactotroph VEGFR2 expression, lifting reproductive axis repression in response to shorter day lengths. The time-dependent, melatonin-induced differential expression of VEGF-A isoforms culminates in alterations in gonadotroph function opposite to those of lactotrophs, with up-regulation and down-regulation of gonadotropin gene expression during the breeding and non-breeding season, respectively. These results provide a novel mechanism by which melatonin can control pituitary function in a seasonal manner

    Voices for food: Methodologies for Implementing a Multi-state Community-based Intervention in Rural, High Poverty communities.

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    BACKGROUND: Rural communities experience unique barriers to food access when compared to urban areas and food security is a public health issue in rural, high poverty communities. A multi-leveled socio-ecological intervention to develop food policy councils (FPCs), and improve food security in rural communities was created. Methods to carry out such an intervention were developed and are described.METHODS: A longitudinal, matched treatment and comparison study was conducted in 24 rural, high poverty counties in South Dakota, Indiana, Missouri, Michigan, Nebraska and Ohio. Counties were assigned to a treatment (n = 12) or comparison (n = 12) group. Intervention activities focus on three key components that impact food security: 1) community coaching by Extension Educators/field staff, 2) FPC development, and 3) development of a MyChoice food pantry. Community coaching was only provided to intervention counties. Evaluation components focus on three levels of the intervention: 1) Community (FPCs), 2) Food Pantry Organization, and 3) Pantry Client & Families. Participants in this study were community stakeholders, food pantry directors, staff/volunteers and food pantry clients. Pantry food access/availability including pantry food quality and quantity, household food security and pantry client dietary intake are dependent variables.DISCUSSION: The results of this study will provide a framework for utilizing a multi-leveled socio-ecological intervention with the purpose of improving food security in rural, high poverty communities. Additionally, the results of this study will yield evidence-based best practices and tools for both FPC development and the transition to a guided-client choice model of distribution in food pantries. TRIAL REGISTRATION: ClinicalTrials.gov; NCT03566095 . Retrospectively registered on June, 21, 2018

    Does lowering the screening age for cervical cancer in The Netherlands make sense?\ud

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    Recommendations for the age to initiate cervical cancer screening should be directed towards maximum detection of early cervical cancer. However, the screening programme should do more good than harm. The aim of this analysis was to determine whether the target age for cervical cancer screening should be lowered in view of apparent increases in new cases of invasive cancer below age 30 and in age group 30–44 years in The Netherlands. Therefore, all cervical cancer cases diagnosed between January 1, 1989 and December 31, 2003 were selected from the nationwide population-based Netherlands Cancer Registry. For age group 25–39 years, incidence data were also available for 2004 and 2005. To describe trends, the estimated annual percentage of change and joinpoint analysis were used. Between ages 25 and 28 years, the absolute number of new cases of cervical cancer annually has varied between 0 and 9 per age. Significantly decreasing trends in incidence were observed for age groups 35–39 and 45–49 (p < 0.0001 and p = 0.01, respectively). The annual number of deaths fluctuated with a decreasing trend for age groups 30–34 and 35–39 years (p = 0.01 and p = 0.03, respectively). Because the incidence and mortality rates for cervical cancer among women younger than 30 are low and not increasing, lowering the age for cervical cancer screening is not useful at this time. Although the number of years of life gained is high for every case of cervical cancer prevented, the disadvantages of lowering the screening age would be very large and even become disproportionate compared to the potential advantage

    Mechanisms regulating angiogenesis underlie seasonal control of pituitary function

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    Seasonal changes in mammalian physiology, such as those affecting reproduction, hibernation and metabolism, are controlled by pituitary hormones released in response to annual environmental changes. In temperate zones, the primary environmental cue driving seasonal reproductive cycles is the change in daylength (photoperiod), encoded by the pattern of melatonin secretion from the pineal gland. However, although reproduction relies on hypothalamic gonadotrophin-releasing hormone (GnRH) output, and most cells producing reproductive hormones are in the pars distalis (PD) of the pituitary, melatonin receptors are localized in the pars tuberalis (PT), a physically and functionally separate part of the gland. How melatonin in the PT controls the PD is not understood. Here we show that melatonin time-dependently acts on its receptors in the PT to alter splicing of vascular endothelial growth factor (VEGF). Outside the breeding season, angiogenic VEGF-A stimulates vessel growth in the infundibulum, aiding vascular communication between the PT, PD and brain. This also acts on VEGFR2 expressed in PD prolactin-producing cells known to impair gonadotrophin secretion. In contrast, in the breeding season, melatonin releases anti-angiogenic VEGF-Axxxb from the PT, inhibiting infundibular angiogenesis and diminishing lactotroph VEGFR2 expression, lifting reproductive axis repression in response to shorter day lengths. The time-dependent, melatonin-induced differential expression of VEGF-A isoforms culminates in alterations in gonadotroph function opposite to those of lactotrophs, with up-regulation and down-regulation of gonadotropin gene expression during the breeding and non-breeding season, respectively. These results provide a novel mechanism by which melatonin can control pituitary function in a seasonal manner

    Are lay people good at recognising the symptoms of schizophrenia?

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    ©2013 Erritty, Wydell. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Aim: The aim of this study was to explore the general public’s perception of schizophrenia symptoms and the need to seekhelp for symptoms. The recognition (or ‘labelling’) of schizophrenia symptoms, help-seeking behaviours and public awareness of schizophrenia have been suggested as potentially important factors relating to untreated psychosis. Method: Participants were asked to rate to what extent they believe vignettes describing classic symptoms (positive and negative) of schizophrenia indicate mental illness. They were also asked if the individuals depicted in the vignettes required help or treatment and asked to suggest what kind of help or treatment. Results: Only three positive symptoms (i.e., Hallucinatory behaviour, Unusual thought content and Suspiciousness) of schizophrenia were reasonably well perceived (above 70%) as indicating mental illness more than the other positive or negative symptoms. Even when the participants recognised that the symptoms indicated mental illness, not everyone recommended professional help. Conclusion: There may be a need to improve public awareness of schizophrenia and psychosis symptoms, particularly regarding an awareness of the importance of early intervention for psychosis
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