453 research outputs found

    Rare and Endangered Vetebrates of Ohio

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    Author Institution: U.S. Soil Conservation Service; Introductory Biology Program, The Ohio State University; School of Natural Resources, The Ohio State University; and Division of Wildlife, Ohio Department of Natural ResourcesThis paper, an annotated list of Ohio's rare and endangered vertebrate species, was compiled to supplement a similar national list and includes 10 mammals, 62 birds, 10 reptiles, 4 amphibians, and 33 fishes. Where possible, suggestions are made both as to causes of the rare or endangered status of these species and as to means of halting the trend. Ratings of endangered, rare, peripheral, or undetermined, as defined for the national classification, are given for each species

    Discovery of a flux-related change of the cyclotron line energy in Her X-1

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    We present the results of ten years of repeated measurements of the Cyclotron Resonance Scattering Feature (CRSF) in the spectrum of the binary X-ray pulsar Her X-1 and report the discovery of a positive correlation of the centroid energy of this absorption feature in pulse phase averaged spectra with source luminosity.Our results are based on a uniform analysis of observations bythe RXTE satellite from 1996 to 2005, using sufficiently long observations of 12 individual 35-day Main-On states of the source. The mean centroid energy E_c of the CRSF in pulse phase averaged spectra of Her X-1 during this time is around 40 keV, with significant variations from one Main-On state to the next. We find that the centroid energy of the CRSF in Her X-1 changes by ~5% in energy for a factor of 2 in luminosity. The correlation is positive, contrary to what is observed in some high luminosity transient pulsars. Our finding is the first significant measurement of a positive correlation between E_c and luminosity in any X-ray pulsar. We suggest that this behaviour is expected in the case of sub-Eddington accretion and present a calculation of a quantitative estimate, which is very consistent with the effect observed in Her X-1.We urge that Her X-1 is regularly monitored further and that other X-ray pulsars are investigated for a similar behaviour.Comment: 4 pages, 2 figures, accepted by A&A Letter

    Kelvin-Helmholtz Instability of the Magnetopause of Disc-Accreting Stars

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    This work investigates the short wavelength stability of the magnetopause between a rapidly-rotating, supersonic, dense accretion disc and a slowly-rotating low-density magnetosphere of a magnetized star. The magnetopause is a strong shear layer with rapid changes in the azimuthal velocity, the density, and the magnetic field over a short radial distance and thus the Kelvin-Helmholtz (KH) instability may be important. The plasma dynamics is treated using non-relativistic, compressible (isentropic) magnetohydrodynamics. It is necessary to include the displacement current in order that plasma wave velocities remain less than the speed of light. We focus mainly on the case of a star with an aligned dipole magnetic field so that the magnetic field is axial in the disc midplane and perpendicular to the disc flow velocity. However, we also give results for cases where the magnetic field is at an arbitrary angle to the flow velocity. For the aligned dipole case the magnetopause is most unstable for KH waves propagating in the azimuthal direction perpendicular to the magnetic field which tends to stabilize waves propagating parallel to it. The wave phase velocity is that of the disc matter. A quasi-linear theory of the saturation of the instability leads to a wavenumber (kk) power spectrum ∝k−1\propto k^{-1} of the density and temperature fluctuations of the magnetopause, and it gives the mass accretion and angular momentum inflow rates across the magnetopause. For self-consistent conditions this mass accretion rate will be equal to the disc accretion rate at large distances from the magnetopause.Comment: 8 pages, 7 figure

    Understanding the threats posed by non-native species: public vs. conservation managers.

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    Public perception is a key factor influencing current conservation policy. Therefore, it is important to determine the influence of the public, end-users and scientists on the prioritisation of conservation issues and the direct implications for policy makers. Here, we assessed public attitudes and the perception of conservation managers to five non-native species in the UK, with these supplemented by those of an ecosystem user, freshwater anglers. We found that threat perception was not influenced by the volume of scientific research or by the actual threats posed by the specific non-native species. Media interest also reflected public perception and vice versa. Anglers were most concerned with perceived threats to their recreational activities but their concerns did not correspond to the greatest demonstrated ecological threat. The perception of conservation managers was an amalgamation of public and angler opinions but was mismatched to quantified ecological risks of the species. As this suggests that invasive species management in the UK is vulnerable to a knowledge gap, researchers must consider the intrinsic characteristics of their study species to determine whether raising public perception will be effective. The case study of the topmouth gudgeon Pseudorasbora parva reveals that media pressure and political debate has greater capacity to ignite policy changes and impact studies on non-native species than scientific evidence alone

    Confirmation of Two Cyclotron Lines in Vela X-1

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    We present pulse phase-resolved X-ray spectra of the high mass X-ray binary Vela X-1 using the Rossi X-ray Timing Explorer. We observed Vela X-1 in 1998 and 2000 with a total observation time of ~90 ksec. We find an absorption feature at 23.3 +1.3 -0.6 kev in the main pulse, that we interpret as the fundamental cyclotron resonant scattering feature (CRSF). The feature is deepest in the rise of the main pulse where it has a width of 7.6 +4.4 -2.2 kev and an optical depth of 0.33 +0.06 -0.13. This CRSF is also clearly detected in the secondary pulse, but it is far less significant or undetected during the pulse minima. We conclude that the well known CRSF at 50.9 +0.6 -0.7 kev, which is clearly visible even in phase-averaged spectra, is the first harmonic and not the fundamental. Thus we infer a magnetic field strength of B=2.6 x 10^12 G.Comment: 12 pages, LaTeX, 15 Figures, accepted by A&

    Patient perspectives of managing fatigue in ankylosing spondylitis, and views on potential interventions: a qualitative study

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    <p>Background: Fatigue is a major component of living with ankylosing spondylitis (AS), though it has been largely over-looked, and currently there are no specific agreed management strategies.</p> <p>Methods: This qualitative exploratory study involved participants who are members of an existing population-based ankylosing spondylitis (PAS) cohort. Participants residing in South West Wales were invited to participate in a focus group to discuss; (1) effects of fatigue, (2) self-management strategies and (3) potential future interventions. The focus groups were audio-recorded and the transcripts were analysed using thematic analysis.</p> <p>Results: Participants consisted of 3 males/4 females (group 1) and 4 males/3 females (group 2), aged between 35 and 73 years (mean age 53 years). Three main themes were identified: (1) The effects of fatigue were multi-dimensional with participants expressing feelings of being ‘drained’ (physical), ‘upset’ (emotional) and experiencing ‘low-mood’ (psychological); (2) The most commonly reported self-management strategy for fatigue was a balanced combination of activity (exercise) and rest. Medication was reluctantly taken due to side-effects and worries over dependency; (3) Participants expressed a preference for psychological therapies rather than pharmacological for managing fatigue. Information on Mindfulness-Based Stress Reduction (MBSR) was received with interest, with recommendations for delivery in a group format with the option of distance-based delivery for people who were not able to attend a group course.</p> <p>Conclusions: Patients frequently try and manage their fatigue without any formal guidance or support. Our research indicates there is a need for future research to focus on psychological interventions to address the multi-faceted aspects of fatigue in AS.</p&gt

    Being in want of control: Experiences of being on the road to, and making, a suicide attempt

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    Attempted suicide is a risk factor for future suicidal behaviour, but understanding suicidality from the perspective of people who have experienced attempted suicide is limited. The aim of the study was to explore the lived experience of being suicidal and having made a suicide attempt, in order to identify possible implications for health care professionals. Semi-structured individual interviews were held with 10 persons shortly after they attempted suicide and were analysed through qualitative content analysis. The participants’ experience of being suicidal and of having attempted suicide could be described as “Being on the road towards suicidal action”, which culminated in an experience of either chaos or turned off emotions, “Making sense of the suicide attempt”, and “Opening the door to possible life lines”. An overall theme, “Being in want of control”, captured their all-embracing lack of sense of control and was seen in relation to different aspects of oneself, overall life-situation, the immediate suicide attempt situation and in the outlook on the future. Being in want of control may be a relevant and general feature of being suicidal. People who have attempted suicide need more adequate help to break vicious circles before they reach a point of no return and enter an acute suicidal state of mind. Patients’ experience-based knowledge is highly important to listen to and use clinically as well as theoretically when constructing suicide prevention programs

    Middle Eastern mothers in Sweden, their experiences of the maternal health service and their partner's involvement

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    <p>Abstract</p> <p>Background</p> <p>Traditional patterns relating to how to handle pregnancy and birth are often challenged due to migration. The purpose of this study was to describe Middle Eastern mothers' experiences of the maternal health care services in Sweden and the involvement of their male partner.</p> <p>Methods</p> <p>Thirteen immigrant mothers from the Middle East who had used the maternal health services in Sweden were interviewed using focus group discussions and individual interviews. These were taped, transcribed and analysed according to Content analysis.</p> <p>Results</p> <p>The four main categories that developed were:</p> <p>‱ Access to the professional midwife</p> <p>‱ Useful counselling</p> <p>‱ Stable motherhood in transition</p> <p>‱ Being a family living in a different culture</p> <p>Conclusion</p> <p>According to the respondents in this study, understanding the woman's native language or her culture was not vital to develop a good relationship with the midwife. Instead the immigrant woman developed trust in the midwife based on the knowledge and the empathy the midwife imparted.</p> <p>Increasing the amount of first trimester antenatal visits could avoid spontaneous visits to the emergency clinic. There was a greater need for involvement and support by the father during the perinatal period, such as caring for older children and carrying out household chores since the mothers' earlier female network was often lost.</p> <p>Clinical implications</p> <p>There is a need to involve immigrant parents in the available parental education in order to prepare them for parenthood in their new country as well as to explore their altered family situation. Collecting immigrant women and their partner's, experiences of maternal health care services offers a possibility to improve the existing care, both in content, access and availability where the timing of visits and content require further evaluation.</p

    Entrepreneurship education as human capital: implications for youth self-employment and conflict mitigation in sub-Saharan Africa

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    Previous research has focused on stable developed economies to predict that human capital and entrepreneurship education (EE) provision at the higher education (HE) level will positively affect entrepreneurial success. This article draws on the outcome of recent EE projects in two HE institutions in a conflict-torn northern Nigeria as a proxy to advocate the introduction of entrepreneurship as a compulsory component into the secondary school curriculum in Sub-Saharan Africa. Using semi-structured interview data, it is found that the provision of EE at secondary education level could help to facilitate human capital development and assist efforts to curb youth unemployment. Specifically, the study suggests that EE comprises both generic and specific human capital that increases an individual’s ability to identify and exploit opportunities, particularly for young people, and in doing so helps to reduce their vulnerability to poverty and involvement in armed conflict. Suggestions for future research and policy considerations are provided

    The IDvIP Trial: A two-centre randomised double-blind controlled trial comparing intramuscular diamorphine and intramuscular pethidine for labour analgesia

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    <p>Abstract</p> <p>Background</p> <p>Intramuscular pethidine is routinely used throughout the UK for labour analgesia. Studies have suggested that pethidine provides little pain relief in labour and has a number of side effects affecting mother and neonate. It can cause nausea, vomiting and dysphoria in mothers and can cause reduced fetal heart rate variability and accelerations. Neonatal effects include respiratory depression and impaired feeding. There are few large studies comparing the relative side effects and efficacy of different opioids in labour. A small trial comparing intramuscular pethidine with diamorphine, showed diamorphine to have some benefits over pethidine when used for labour analgesia but the study did not investigate the adverse effects of either opioid.</p> <p>Methods</p> <p>The Intramuscular Diamorphine versus Intramuscular Pethidine (IDvIP) trial is a randomised double-blind two centre controlled trial comparing intramuscular diamorphine and pethidine regarding their analgesic efficacy in labour and their side effects in mother, fetus and neonate. Information about the trial will be provided to women in the antenatal period or in early labour. Consent and recruitment to the trial will be obtained when the mother requests opioid analgesia. The sample size requirement is 406 women with data on primary outcomes. The maternal primary outcomes are pain relief during the first 3 hours after trial analgesia and specifically pain relief after 60 minutes. The neonatal primary outcomes are need for resuscitation and Apgar Score <7 at 1 minute. The secondary outcomes are an additional measure of pain relief, maternal sedation, nausea and vomiting, maternal oxygen saturation, satisfaction with analgesia, whether method of analgesia would be used again, use of Entonox, umbilical arterial and venous pH, fetal heart rate, meconium staining, time from delivery to first breath, Apgar scores at 5 mins, naloxone requirement, transfer to neonatal intensive care unit, neonatal haemoglobin oxygen saturation at 30, 60, 90, and 120 mins after delivery, and neonatal sedation and feeding behaviour during first 2 hours.</p> <p>Discussion</p> <p>If the trial demonstrates that diamorphine provides better analgesia with fewer side effects in mother and neonate this could lead to a change in national practice and result in diamorphine becoming the preferred intramuscular opioid for analgesia in labour.</p> <p>Trial Registration</p> <p><a href="http://www.controlled-trials.com/ISRCTN14898678">ISRCTN14898678</a></p> <p>Eudra No: 2006-003250-18, REC Reference No: 06/Q1702/95, MHRA Authorisation No: 1443/0001/001-0001, NIHR UKCRN reference 6895, RfPB grant PB-PG-0407-13170_IR5</p
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