520 research outputs found

    Prevalence and Determinants of Bullying Among Health Care Workers in Portugal

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    Bullying is defined as systematic exposure to humiliation as well as hostile and violent behaviors against one or more individuals. These behaviors are a serious, growing problem, which affects a significant proportion of health care professionals. To support the hospital’s risk management policy, a cross-sectional study was undertaken to determine the prevalence of bullying in this institution and identify the determinants of bullying. Bullying was measured using the Negative Acts Questionnaire–Revised, Portuguese version (NAQ-R), a self-administered tool. The questionnaire was made available in digital format on the hospital’s internal network (Intranet) and in hard copy; questionnaires were returned via nonidentified internal mail addressed to the occupational health unit or deposited in suggestion boxes located throughout the hospital. Multiple questionnaire delivery methods guaranteed data anonymity and confidentiality. The prevalence of bullying in this hospital was 8% (95% confidence interval [CI] = [6.2, 10.2]). Reported bullying was predominantly vertical and more frequently occurring among nurses, clerical staff, and health care assistants (12.5%, 7.6%, 6.4%, respectively; p = .005). After adjusting for gender, age, occupation, type of contract, and work schedule, only type of contract was significantly associated with bullying in the workplace; the risk of bullying was twice as high among government employees compared to workers with indefinite duration employment contracts (p = .038). This study identified a high prevalence of bullying among health professionals; hence a program to prevent and control this phenomenon was implemented in this institution

    First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

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    Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

    Psychoimmunology Consultation - A Study on Comorbidity

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    Introdução: Os doentes VIH-positivos notificados apresentam taxas de prevalência superiores à população geral para a maioria das perturbações mentais, com valores atingindo os 30 a 60%. Objetivos: Caracterizar a população que é referenciada à consulta de Psiquiatria-Psicoimunologia; explorar a possível relação entre o diagnóstico psiquiátrico e as restantes variá- veis em estudo; assim como a possível associa- ção do tratamento antirretrovírico e da coinfe- ção pelo VHC com variáveis sociodemográficas e clínicas. Métodos: Selecionámos os doentes VIH-positivos referenciados pela primeira vez à consulta de Psiquiatria-Psicoimunologia, entre janeiro de 2012 e julho de 2015. A informação necessária acerca dos mesmos foi recolhida através do processo clínico em suporte informático. A análise estatística foi efetuada utilizando o programa de análise estatística Statistical Package for Social Sciences©, versão 20. Resultados: A amostra continha 209 doentes, com uma mediana de idades de 43 anos, maioritariamente homens, com quatro anos de escolaridade, solteiros, profissionalmente inativos, infetados via comportamento heterossexual. Porém, verificámos diferenças estatisticamente significativas entre sexos para as últimas três variáveis. A maior parte encontrava-se sob tratamento antirretrovírico, sem diferenças significativas entre sexos. Na primeira consulta, 29,0% e 30,1% apresentavam, respetivamente, consumo de substâncias e coinfeção pelo VHC, com predomínio significativo nos homens. Mais de metade tinha antecedentes psiquiátricos, e os sintomas depressivos e a perturbação de adaptação à doença constituíram, respetivamente, o motivo de referenciação e o diagnóstico psiquiátrico mais frequente, em ambos os sexos. A coinfecção pelo VHC correlacionou-se de forma estatisticamente significativa com as variáveis sexo, situação ocupacional, via de transmissão da infeção, história psiquiátrica e consumo de álcool e/ou drogas ilícitas. O mesmo aconteceu entre o diagnóstico psiquiátrico e as variáveis tempo de notificação da infeção, consumo de álcool e/ou drogas e coinfeção pelo VHC.Conclusões: Ao longo do curso da infeção, estes doentes deparam-se frequentemente com múltiplos stressores que podem torná-los mais vulneráveis ao adoecimento psíquico. A disponibilidade de uma assistência psiquiá- trica eficaz revela-se, portanto, crucial, sendo necessário o aumento de investigação futura nesta área.info:eu-repo/semantics/publishedVersio

    First measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo Binary–Black-hole Merger GW170814

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    International audienceWe present a multi-messenger measurement of the Hubble constant H 0 using the binary–black-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in , which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km s−1 Mpc−1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km s−1 Mpc−1, we find (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0

    Sensitivity of the Advanced LIGO detectors at the beginning of gravitational wave astronomy

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    The Laser Interferometer Gravitational Wave Observatory (LIGO) consists of two widely separated 4 km laser interferometers designed to detect gravitational waves from distant astrophysical sources in the frequency range from 10 Hz to 10 kHz. The first observation run of the Advanced LIGO detectors started in September 2015 and ended in January 2016. A strain sensitivity of better than 10−23/Hz−−−√ was achieved around 100 Hz. Understanding both the fundamental and the technical noise sources was critical for increasing the astrophysical strain sensitivity. The average distance at which coalescing binary black hole systems with individual masses of 30  M⊙ could be detected above a signal-to-noise ratio (SNR) of 8 was 1.3 Gpc, and the range for binary neutron star inspirals was about 75 Mpc. With respect to the initial detectors, the observable volume of the Universe increased by a factor 69 and 43, respectively. These improvements helped Advanced LIGO to detect the gravitational wave signal from the binary black hole coalescence, known as GW150914

    Localization and Broadband Follow-Up of the Gravitational-Wave Transient GW150914

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    A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser InterferometerGravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimatesof the time, significance, and sky location of the event were shared with 63 teams of observers covering radio,optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter wedescribe the low-latency analysis of the GW data and present the sky localization of the first observed compactbinary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-rayCoordinates Network circulars, giving an overview of the participating facilities, the GW sky localizationcoverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger,there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadbandcampaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broadcapabilities of the transient astronomy community and the observing strategies that have been developed to pursueneutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-upcampaign are being disseminated in papers by the individual teams

    Search for post-merger gravitational waves from the remnant of the binary neutron star merger GW170817

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    In Advanced LIGO, detection and astrophysical source parameter estimation of the binary black hole merger GW150914 requires a calibrated estimate of the gravitational-wave strain sensed by the detectors. Producing an estimate from each detector's differential arm length control loop readout signals requires applying time domain filters, which are designed from a frequency domain model of the detector's gravitational-wave response. The gravitational-wave response model is determined by the detector's opto-mechanical response and the properties of its feedback control system. The measurements used to validate the model and characterize its uncertainty are derived primarily from a dedicated photon radiation pressure actuator, with cross-checks provided by optical and radio frequency references. We describe how the gravitational-wave readout signal is calibrated into equivalent gravitational-wave-induced strain and how the statistical uncertainties and systematic errors are assessed. Detector data collected over 38 calendar days, from September 12 to October 20, 2015, contain the event GW150914 and approximately 16 of coincident data used to estimate the event false alarm probability. The calibration uncertainty is less than 10% in magnitude and 10 degrees in phase across the relevant frequency band 20 Hz to 1 kHz

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
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