294 research outputs found

    Temporal Evolution of the Vela Pulsar's Pulse Profile

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    The mechanisms of emission and changes in rotation frequency ('glitching') of the Vela pulsar (J0835-4510) are not well understood. Further insight into these mechanisms can be achieved by long-term studies of integrated pulse width, timing residuals, and bright pulse rates. We have undertaken an intensive observing campaign of Vela and collected over 6000 hours of single pulse data. The data shows that the pulse width changes with time, including marked jumps in width after micro-glitches (frequency changes). The abundance of bright pulses also changes after some micro-glitches, but not all. The secular changes in pulse width have three possible cyclic periods, that match with X-ray periodicities of a helical jet that are interpreted as free precession.Comment: 6 pages, 8 figures. Accepted for publication in The Astrophysical Journa

    Trends in method-specific suicide in Brazil from 2000 to 2017

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    Purpose: Understanding long-term patterns of suicide methods can inform public health policy and prevention strategies. In Brazil, firearm-related policies may be one salient target for suicide prevention. This study describes trends in method-specific suicide at the national and state-levels in Brazil, with a particular focus on firearm-related suicides. / Methods: Brazilian mortality data for suicide and undetermined intent among people aged 10 years and older between 2000 and 2017 were obtained from the National Mortality Information System. We examined national and state-level trends in age-standardised suicide rates for hanging, self-poisoning, firearms, jumping from a high place, other, and unspecified methods. We also compared total rates of mortality from suicide and undetermined intent over the period. Applying Joinpoint regression, we tested changes in trends of firearm-specific suicide rates. / Results: The total suicide rate increased between 2000 and 2017. Rates of hanging, self-poisoning by drugs or alcohol and jumping from a high place showed the largest increases, while firearm-specific suicide rates decreased over the study period. Trends in methods of suicide varied by sex and state. / Conclusion: It is of public health concern that suicide rates in Brazil have risen this millennium. Restricting access to firearms might be an effective approach for reducing firearm-specific suicides, especially in states where firearm availability remains particularly high. Treatment and management of substance misuse may also be an important target for suicide prevention policies. More work is needed to understand the causes of rising suicide rates in Brazil and to improve the mental health of the population

    Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE

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    Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae (PWNe) are observed in the radio, optical, x-rays and, in some cases, also at TeV energies, but the lack of information in the gamma-ray band prevents from drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission, probing multivavelength PWN models, and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified Galactic gamma-ray sources.Comment: Accepted by Science; first published online on December 31, 2009 in Science Express. Science article and Supporting Online Material are available at http://www.sciencemag.or

    Burkholderia cenocepacia ET12 strain activates TNFR1 signalling in cystic fibrosis airway epithelial cells

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    Burkholderia cenocepacia is an important pulmonary pathogen in individuals with cystic fibrosis (CF). Infection is often associated with severe pulmonary inflammation, and some patients develop a fatal necrotizing pneumonia and sepsis (‘cepacia syndrome’). The mechanisms by which this species causes severe pulmonary inflammation are poorly understood. Here, we demonstrate that B. cenocepacia BC7, a potentially virulent representative of the epidemic ET12 lineage, binds to tumour necrosis factor receptor 1 (TNFR1) and activates TNFR1-related signalling pathway similar to TNF-α, a natural ligand for TNFR1. This interaction participates in stimulating a robust IL-8 production from CF airway epithelial cells. In contrast, BC45, a less virulent ET12 representative, and ATCC 25416, an environmental B. cepacia strain, do not bind to TNFR1 and stimulate only minimal IL-8 production from CF cells. Further, TNFR1 expression is increased in CF airway epithelial cells compared with non-CF cells. We also show that B. cenocepacia ET12 strain colocaizes with TNFR1 in vitro and in the lungs of CF patients who died due to infection with B. cenocepacia, ET12 strain. Together, these results suggest that interaction of B. cenocepacia , ET12 strain with TNFR1 may contribute to robust inflammatory responses elicited by this organism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73011/1/j.1462-5822.2007.01029.x.pd

    Prescribing for the management of venous leg ulceration

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    Venous leg ulceration affects a large proportion of the elderly population and can have a profound impact on quality of life. Most patients with leg ulcers receive care from community nurses who are principally responsible for prescribing decisions in the management of venous leg ulceration. There is evidence to support the use of potable tap water for cleansing. Evidence supports the use of compression bandaging or compression hosiery for all patients with adequate arterial supply to the lower leg. There is also good evidence to support the prescription of oral pentoxifylline, preferably as an adjunct to compression or, for patients unable to tolerate compression, as a stand-alone therapy. The evidence base for dressings is less robust, but simple low-cost, low-adherent dressings are a reasonable first-line choice for under-compression

    Sources of evidence in HIV/AIDS care: pilot study comparing family physicians and AIDS service organization staff

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    BACKGROUND: The improvement of the quality of the evidence used in treatment decision-making is especially important in the case of patients with complicated disease processes such as HIV/AIDS for which multiple treatment strategies exist with conflicting reports of efficacy. Little is known about the perceptions of distinct groups of health care workers regarding various sources of evidence and how these influence the clinical decision-making process. Our objective was to investigate how two groups of treatment information providers for people living with HIV/AIDS perceive the importance of various sources of treatment information. METHODS: Surveys were distributed to staff at two local AIDS service organizations and to family physicians at three community health centres treating people living with HIV/AIDS. Participants were asked to rate the importance of 10 different sources of evidence for HIV/AIDS treatment information on a 5-point Likert-type scale. Mean rating scores and relative rankings were compared. RESULTS: Findings suggest that a discordance exists between the two health information provider groups in terms of their perceptions of the various sources of evidence. Furthermore, AIDS service organization staff ranked health care professionals as the most important source of information whereas physicians deemed AIDS service organizations to be relatively unimportant. The two groups appear to share a common mistrust for information from pharmaceutical industries. CONCLUSIONS: Discordance exists between medical "experts" from different backgrounds relating to their perceptions of evidence. Further investigation is warranted in order to reveal any effects on the quality of treatment information and implications in the decision-making process. Possible effects on collaboration and working relationships also warrant further exploration

    Effectiveness of acupuncture, special dressings and simple, low-adherence dressings for healing venous leg ulcers in primary healthcare: study protocol for a cluster-randomized open-labeled trial

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    <p>Abstract</p> <p>Background</p> <p>Venous leg ulcers constitute a chronic recurring complaint that affects 1.0–1.3% of the adult population at some time in life, and which corresponds to approximately 75% of all chronic ulcers of the leg. Multilayer compression bandaging is, at present, the only treatment that has been proved to be effective in treating this type of ulcer. There is no consensus, however, about the dressings that may be applied, beneath the compression, to promote the healing of this type of ulcer, as there does not seem to be any added benefit from using special dressings rather than simple, low-adherence ones. As well as analgesia, acupuncture provokes peripheral vasodilation, in skin and muscles – which has been demonstrated both experimentally and in clinical practice – probably due to the axon reflex, among other mechanisms. The aim of the present study is to measure the effectiveness and cost of compression treatment for venous leg ulcers combined with special dressings, in comparison with low-adherence ones and acupuncture.</p> <p>Methods/design</p> <p>Cluster-randomized open-labeled trial, at 15 primary healthcare clinics in the Sevilla-Sur Healthcare District, with a control group treated with compression bandaging and low-adherence dressings; the experiment will consist, on the one hand, of the compression treatment applied in combination with special dressings (Treatment 1), and on the other, the compression treatment applied in association with low-adherence dressings, together with acupuncture (Treatment 2).</p> <p>Discussion</p> <p>The results will be measured and recorded in terms of the median time elapsed until complete healing of the ulcer, and the rate of complete healing at 3 months after beginning the treatment. An economic analysis will also be made.</p> <p>This study, carried out in the context of real clinical practice, will provide information for decision-taking concerning the effectiveness of special dressings. Moreover, for the first time a high-quality study will evaluate the effectiveness of acupuncture in the process of healing venous leg ulcers.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN26438275.</p

    Exploring the role of organizational policies and procedures in promoting research utilization in registered nurses

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    <p>Abstract</p> <p>Background</p> <p>Policies and procedures (P&Ps) have been suggested as one possible strategy for moving research evidence into practice among nursing staff in hospitals. Research in the area of P&Ps is limited, however. This paper explores: 1) nurses' use of eight specific research-based practices (RBPs) and RBP overall, 2) nurses' use and understanding of P&Ps, and 3) the role of P&Ps in promoting research utilization.</p> <p>Methods</p> <p>Staff nurses from the eight health regions governing acute care services across the Canadian province of Newfoundland and Labrador completed an anonymous questionnaire regarding their use of eight RBPs and associated P&Ps. Data were also obtained from authorities in six of the eight regions about existing relevant P&Ps. We used descriptive statistics and multivariate regression analysis to assess the relationship between key independent variables and self-reported use of RBP.</p> <p>Results</p> <p>Use of the eight RBPs ranged from 7.8% to 88.6%, depending on the practice. Nurses ranked P&P manuals as their number one source of practice knowledge. Most respondents (84.8%) reported that the main reason they consult the P&P manual is to confirm they are practicing according to agency rules. Multivariate regression analysis identified three significant predictors of being a user versus non-user of RBP overall: awareness, awareness by regular use, and persuasion. Six significant predictors of being a consistent versus less consistent user of RBP overall were also identified: perception of P&P existence, unit, nursing experience, personal experience as a source of practice knowledge, number of existing research-based P&Ps, and lack of time as a barrier to consulting P&P manuals.</p> <p>Conclusion</p> <p>Findings suggest that nurses use P&Ps to guide their practice. However, the mere existence of P&Ps is not sufficient to translate research into nursing practice. Individual and organizational factors related to nurses' understanding and use of P&Ps also play key roles. Thus, moving research evidence into practice will require careful interplay between the organization and the individual. P&Ps may be the interface through which this occurs.</p
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