430 research outputs found

    A scanning electron microscopic study of the sacculus and lagena in the ears of fifteen species of teleost fishes

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    The ulstrastructure of the saccular and lagenar maculae were studied in 15 species of teleost fishes, using the scanning electron microscope. Particular attention was paid to hair cell orientation patterns, composition of the ciliary bundles on the hair cells, hair cell distributions, and supporting cell types. The hair cells on both otolithic organs are divided into several groups with all of the hair cells in each group oriented in the same direction. The posterior region of the saccular macula in all species had dorsally oriented hair cells on the dorsal half of the macula and ventrally oriented hair cells on the ventral half. The cells on the anterior end of the macula were oriented anteriorly and posteriorly, with the posterior group, in most species, being on the dorsal half of the anterior region of the macula. There was considerable inter-specific variation upon this basic pattern. Inter-specific variation on the lagenar macula was considerably less than on the saccular macula. The basic pattern in all of the species includes one dorsal cell group and one ventral cell group. There are four more-or-less discrete ciliary bundles, each varying in the relative size of the kinocilia and stereocilia. Intermediary forms were also observed, making it difficult to differentiate ciliary bundles in some instances. It was apparent, however, that several of the ciliary bundles were found in particular macular regions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50266/1/1051530306_ftp.pd

    The mechanism of disaster capitalism and the failure to build community resilience:learning from the 2009 earthquake in L'Aquila, Italy

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    This paper reflects on what materialised during recovery operations following the earthquake in L'Aquila, Italy, on 6 April 2009. Previous critiques have focused on the actions of the Government of Italy and the Department of Civil Protection (Protezione Civile), with little attention paid to the role of local authorities. This analysis sheds light on how the latter used emergency powers, the command-and-control approach, and top-down planning to manage the disaster context, especially in terms of removal of rubble, implementing safety measures, and allocating temporary accommodation. It discusses how these arrangements constituted the mechanism via which ‘disaster capitalism’ took hold at the local and national level, and how it violated human rights, produced environmental and social impacts, hindered local communities from learning, transforming, and building resilience, and facilitated disaster capitalism and corruption. To make the disaster risk reduction and resilience paradigm more effective, a shift from centralised civil protection to decentralised, inclusive community empowerment systems is needed

    Schistosoma mansoni : use of a fluorescent indicator to detect nitric oxide and related species in living parasites

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    Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Experimental Parasitology 113 (2006): 130-133, doi:10.1016/j.exppara.2005.12.013.Nitric oxide (NO) is synthesized enzymatically by nitric oxide synthase (NOS). Several groups have previously presented evidence for NOS activity and immunoreactivity in several parasitic platyhelminths, including schistosomes. Here, we use 4,5-diaminofluorescein-2 diacetate (DAF-2 DA), a fluorescent indicator of NO, to detect NO in living schistosomes. In adult worms, DAF-2 fluorescence is found selectively in epithelial-like cells. Fluorescence increases when worms are incubated in L-arginine, the precursor of NO synthesis, and decreases dramatically in the presence of the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME), indicating that predicted NO release may be NOS-dependent, and that enzymatic NO signaling pathways may play an important role in schistosome physiology.This work was supported by NIH grant NS 39103 and NSF grants 0304569 (LLM), and NIH grant AI 40522 and the Neal Cornell Research Fund at the Marine Biological Laboratory (RMG)

    Workplace violence experienced by nursing students: A UK survey

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    © 2016 Elsevier Ltd. Aims: To appreciate the nature and scope of workplace violence amongst a sample of the UK nursing student population during clinical placement and to recommend strategies universities can implement to successfully manage the impact. Background: Workplace violence is defined as a violent act(s) directed toward workers and can include physical, psychological or verbal behaviour. It is prevalent in nursing and causes victims work-based stress that can affect not only the individual but also the quality of care. Similar negative experiences amongst students can have a direct impact on the development of future professional skills. Design: This study employed a cross-sectional survey design. Questions were uploaded in the format of a commercial internet survey provider (SurveyMonkey.com) and distributed across a sample of nursing schools in the UK. The survey was voluntary and employed a validated tool to assess workplace violence and was based on a similar study in Australia. The number of respondents was 657. This paper reports on the quantitative results. Findings: Nearly half of the students (42.18%) indicated they had experienced bullying/harassment in the past year while on clinical placement. One-third (30.4%) had witnessed bullying/harassment of other students and 19.6% of incidents involved a qualified nurse. The unwanted behaviours made some students consider leaving nursing (19.8%). Some respondents said the standard of patient care (12.3%) and their work with others (25.9%) were negatively affected. Conclusions: Workplace violence can influence nursing students' attitude toward the profession and their level of satisfaction with the work. Whilst it was reassuring to note that the majority of the participants knew where/how to report, only one fifth had actively reported an episode of bullying/harassment. Current students are the nurses and leaders of the future and have a key role in shaping the culture of generations to come. Universities and clinical providers need to work together to reduce the incidence and impact of workplace violence in order to improve the culture of practice

    Construction, Concentration, and (Dis)Continuities in Social Valuations

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    I review and integrate recent sociological research that makes progress on three interrelated questions pertaining to social valuation: (a) the degree of social construction relative to objective constraints; (b) the degree of concentration in social valuations at a single point in time; and (c) the conditions that govern two broad forms of temporal discontinuity—(i) fashion cycles, especially in cultural expression and in managerial practices, and (ii) bubble/crash dynamics, as witnessed in such domains as authoritarian regimes and financial markets. In the course of the review, I argue for the importance of identifying how objective conditions constrain social construction and suggest two contrarian mechanisms by which this is accomplished—valuation opportunism and valuation entrepreneurship—and the conditions under which they are more or less effective

    MicroRNA-22 Regulates Hypoxia Signaling in Colon Cancer Cells

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    MicroRNAs (MiRNAs) are short, non-coding RNA that regulate a variety of cellular functions by suppressing target protein expression. We hypothesized that a set of microRNA regulate tumor responses to hypoxia by inhibiting components of the hypoxia signaling pathway. We found that miR-22 expression in human colon cancer is lower than in normal colon tissue. We also found that miR-22 controls hypoxia inducible factor 1α (HIF-1α) expression in the HCT116 colon cancer cell line. Over-expression of miR-22 inhibits HIF-1α expression, repressing vascular endothelial growth factor (VEGF) production during hypoxia. Conversely, knockdown of endogenous miR-22 enhances hypoxia induced expression of HIF-1α and VEGF. The conditioned media from cells over-expressing miR-22 contain less VEGF protein than control cells, and also induce less endothelial cell growth and invasion, suggesting miR-22 in adjacent cells influences endothelial cell function. Taken together, our data suggest that miR-22 might have an anti-angiogenic effect in colon cancer

    Measurement of the imaginary part of the I=1 N-barN S-wave scattering length

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    The survival time spectrum of slow antineutrons produced in a liquid-hydrogen target has been measured. From these data the imaginary part of the I=1 spin-averaged S-wave antineutron proton scattering length has been deduced to be Ima1=-0.83±0.07 fm. The result lies within the range of values calculated from current potential models. In addition, by combining a1 with the antiproton-proton scattering length deduced from antiprotonic atoms, the imaginary part of the I=0 spin-averaged N¯N scattering length was calculated to be Ima0=-1.07±0.16 fm

    Epileptogenesis after prolonged febrile seizures: mechanisms, biomarkers and therapeutic opportunities.

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    Epidemiological and recent prospective analyses of long febrile seizures (FS) and febrile status epilepticus (FSE) support the idea that in some children, such seizures can provoke temporal lobe epilepsy (TLE). Because of the high prevalence of these seizures, if epilepsy was to arise as their direct consequence, this would constitute a significant clinical problem. Here we discuss these issues, and describe the use of animal models of prolonged FS and of FSE to address the following questions: Are long FS epileptogenic? What governs this epileptogenesis? What are the mechanisms? Are there any predictive biomarkers of the epileptogenic process, and can these be utilized, together with information about the mechanisms of epileptogenesis, for eventual prevention of the TLE that results from long FS and FSE

    Patients with Alcohol Problems in the Emergency Department, Part 1: Improving Detection *

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    Medical and social problems related to alcohol use are frequently seen in the ED. Often, the tempo of emergency medicine practice seems to preclude assessment beyond that required by the acute complaint. However, detection of ED patients with alcohol problems can occur using brief screening tools. This article was developed by members of the SAEM Substance Abuse Task Force, and describes screening tools that have been used successfully to identify atrisk and dependent drinkers. Their brevity, reproducibility, and accuracy vary somewhat, but screening can be realistically performed in the busy ED setting. The early detection of patients with alcohol problems would provide the opportunity for early intervention, and may reduce subsequent morbidity and mortality in this patient population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72559/1/j.1553-2712.1998.tb02696.x.pd

    The Impact of Immigration on the Wage Distribution in Switzerland

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    Recent immigrants in Switzerland are overrepresented at the top of the wage distribution in high and at the bottom in low skill occupations. Basic economic theory thus suggests that immigration has led to a compression of the wage distribution in the former group and to an expansion in the latter. The data confirm this proposition for high skill occupations, but reveal effects close to zero for low skill occupations. While the estimated wage effects are of considerable magnitude at the tails of the wage distribution in high skill occupations, the effects on overall inequality are shown to be negligible
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