264 research outputs found

    Key worker services for disabled children: what characteristics of services lead to better outcomes for children and families?

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    Background: Research has shown that families of disabled children who have a key worker benefit from this service and recent policy initiatives emphasize the importance of such services. However, research is lacking on which characteristics of key worker schemes for disabled children are related to better outcomes for families. Methods: A postal questionnaire was completed by 189 parents with disabled children who were receiving a service in seven key worker schemes in England and Wales. Path analysis was used to investigate associations between characteristics of the services and outcomes for families (satisfaction with the service, impact of key worker on quality of life, parent unmet need, child unmet need). Results: The four path models showed that key workers carrying out more aspects of the key worker role, appropriate amounts of contact with key workers, regular training, supervision and peer support for key workers, and having a dedicated service manager and a clear job description for key workers were associated with better outcomes for families. Characteristics of services had only a small impact on child unmet need, suggesting that other aspects of services were affecting child unmet need. Conclusions: Implications for policy and practice are discussed, including the need for regular training, supervision and peer support for key workers and negotiated time and resources for them to carry out the role. These influence the extent to which key workers carry out all aspects of the key worker's role and their amount of contact with families, which in turn impact on outcomes

    Constraints on cosmic strings using data from the first Advanced LIGO observing run

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    Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such signals was found in the data, and as a result we set upper limits on the cosmic string parameters for three recent loop distribution models. In this paper, we initially derive constraints on the string tension Gμ and the intercommutation probability, using not only the burst analysis performed on the O1 data set but also results from the previously published LIGO stochastic O1 analysis, pulsar timing arrays, cosmic microwave background and big-bang nucleosynthesis experiments. We show that these data sets are complementary in that they probe gravitational waves produced by cosmic string loops during very different epochs. Finally, we show that the data sets exclude large parts of the parameter space of the three loop distribution models we consider

    Full band all-sky search for periodic gravitational waves in the O1 LIGO data

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    We report on a new all-sky search for periodic gravitational waves in the frequency band 475–2000 Hz and with a frequency time derivative in the range of ½−1.0; þ0.1 × 10−8 Hz=s. Potential signals could be produced by a nearby spinning and slightly nonaxisymmetric isolated neutron star in our Galaxy. This search uses the data from Advanced LIGO’s first observational run O1. No gravitational-wave signals were observed, and upper limits were placed on their strengths. For completeness, results from the separately published low-frequency search 20–475 Hz are included as well. Our lowest upper limit on worst-case (linearly polarized) strain amplitude h0 is ∼4 × 10−25 near 170 Hz, while at the high end of our frequency range, we achieve a worst-case upper limit of 1.3 × 10−24. For a circularly polarized source (most favorable orientation), the smallest upper limit obtained is ∼1.5 × 10−25

    Directional Limits on Persistent Gravitational Waves from Advanced LIGO’s First Observing Run

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    We employ gravitational-wave radiometry to map the stochastic gravitational wave background expected from a variety of contributing mechanisms and test the assumption of isotropy using data from the Advanced Laser Interferometer Gravitational Wave Observatory’s (aLIGO) first observing run. We also search for persistent gravitational waves from point sources with only minimal assumptions over the 20–1726 Hz frequency band. Finding no evidence of gravitational waves from either point sources or a stochastic background, we set limits at 90% confidence. For broadband point sources, we report upper limits on the gravitational wave energy flux per unit frequency in the range Fα;ΘðfÞ < ð0.1–56Þ × 10−8 erg cm−2 s−1 Hz−1ðf=25 HzÞα−1 depending on the sky location Θ and the spectral power index α. For extended sources, we report upper limits on the fractional gravitational wave energy density required to close the Universe of Ωðf; ΘÞ < ð0.39–7.6Þ × 10−8 sr−1ðf=25 HzÞα depending on Θ and α. Directed searches for narrowband gravitational waves from astrophysically interesting objects (Scorpius X-1, Supernova 1987 A, and the Galactic Center) yield median frequency-dependent limits on strain amplitude of h0 < ð6.7; 5.5; and 7.0Þ × 10−25, respectively, at the most sensitive detector frequencies between 130–175 Hz. This represents a mean improvement of a factor of 2 across the band compared to previous searches of this kind for these sky locations, considering the different quantities of strain constrained in each case

    Prospects for observing and localizing gravitational-wave transients with Advanced LIGO, Advanced Virgo and KAGRA

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    We present possible observing scenarios for the Advanced LIGO, Advanced Virgo and KAGRA gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We estimate the sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron star systems, which are the most promising targets for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and 90% credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5– 20 deg2 requires at least three detectors of sensitivity within a factor of ∼2 of each other and with a broad frequency bandwidth. When all detectors, including KAGRA and the third LIGO detector in India, reach design sensitivity, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone

    Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light

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    Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer’s dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1  dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%–8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded

    Evaluation of the public health impacts of traffic congestion: a health risk assessment

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    Background: Traffic congestion is a significant issue in urban areas in the United States and around the world. Previous analyses have estimated the economic costs of congestion, related to fuel and time wasted, but few have quantified the public health impacts or determined how these impacts compare in magnitude to the economic costs. Moreover, the relative magnitudes of economic and public health impacts of congestion would be expected to vary significantly across urban areas, as a function of road infrastructure, population density, and atmospheric conditions influencing pollutant formation, but this variability has not been explored. Methods: In this study, we evaluate the public health impacts of ambient exposures to fine particulate matter (PM2.5) concentrations associated with a business-as-usual scenario of predicted traffic congestion. We evaluate 83 individual urban areas using traffic demand models to estimate the degree of congestion in each area from 2000 to 2030. We link traffic volume and speed data with the MOBILE6 model to characterize emissions of PM2.5 and particle precursors attributable to congestion, and we use a source-receptor matrix to evaluate the impact of these emissions on ambient PM2.5 concentrations. Marginal concentration changes are related to a concentration-response function for mortality, with a value of statistical life approach used to monetize the impacts. Results: We estimate that the monetized value of PM2.5-related mortality attributable to congestion in these 83 cities in 2000 was approximately 31billion(2007dollars),ascomparedwithavalueoftimeandfuelwastedof31 billion (2007 dollars), as compared with a value of time and fuel wasted of 60 billion. In future years, the economic impacts grow (to over 100billionin2030)whilethepublichealthimpactsdecreaseto100 billion in 2030) while the public health impacts decrease to 13 billion in 2020 before increasing to $17 billion in 2030, given increasing population and congestion but lower emissions per vehicle. Across cities and years, the public health impacts range from more than an order of magnitude less to in excess of the economic impacts. Conclusions: Our analyses indicate that the public health impacts of congestion may be significant enough in magnitude, at least in some urban areas, to be considered in future evaluations of the benefits of policies to mitigate congestion

    An evaluation of prescribing practices for community-acquired pneumonia (CAP) in Mongolia

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    BACKGROUND: Community-acquired pneumonia (CAP) is a significant cause of morbidity and mortality in all age groups worldwide. It may be classified as mild/moderate or severe, the latter usually requiring hospitalisation. Although, there are many studies reported in relation to CAP, there is relatively little known about the treatment of CAP and its antibiotic use in Mongolia. The study aim was to evaluate prescribing practices for the treatment of mild/moderate CAP in Mongolia with respect to national prescribing guidelines. METHODS: Written prescriptions with a written diagnosis of CAP included were collected prospectively and sequentially for ten weeks from a purposefully selected sample of community pharmacies in rural and urban areas of Mongolia. The data collected included the patient's age, gender, medication details, frequency and number of doses prescribed. Evaluation was with respect to the Mongolian Standard Treatment Guidelines (2005, 2008). Statistical differences between groups were tested using the Chi-squared and Fisher's exact tests.RESULTS: Prescriptions were collected from 22 pharmacies and represented the prescribing practices of 118 doctors. The study enrolled 394 (193 adults and 201 children) patients, with a median age for children of 2.0 years (range: 0.03-12) and adults of 33.0 years (range: 13--92).The most commonly prescribed drugs were amino penicillins, vitamins, and mucolytics, with the median number of drugs being three per prescription. Inappropriate drug selection was similar for adults (57.7%) and children (56.6%), and the major reason for an overall frequency of inappropriate prescribing for adults were 89.0% and for children 78.0%. Doctors in urban areas prescribed more inappropriate drugs than those in rural areas for both children and adults, p = .0014. The proportion of prescribed injections was 28.4% for adults and 9.0% for children, and for adults was significantly higher in urban areas. The prescribing standard for non-hospitalized patients in Mongolia states that injections should not be prescribed. CONCLUSIONS: The high level of inappropriate prescribing for mild/moderate CAP highlights the need to develop comprehensive and reliable procedures nationwide to improve prescribing practices in Mongolia

    Health equity issues at the local level: Socio-geography, access, and health outcomes in the service area of the Hôpital Albert Schweitzer-Haiti

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    <p>Abstract</p> <p>Background</p> <p>Although health equity issues at regional, national and international levels are receiving increasing attention, health equity issues at the local level have been virtually overlooked. Here, we describe here a comprehensive equity assessment carried out by the Hôpital Albert Schweitzer-Haiti (HAS) in 2003. HAS has been operating health and development programs in the Artibonite Valley of Haiti for 50 years.</p> <p>Methods</p> <p>We reviewed all available information arising from a comprehensive evaluation of the programs of HAS carried out in 1999 and 2000. As part of this evaluation, two demographic and health surveys were carried out. We carried out exit interviews with clients receiving primary health care, observations within health facilities, interviews with households related to quality of care, and focus group discussions with community-based health workers. A special study was carried out in 2003 to assess factors determining the use of prenatal care services. Finally, selected findings were obtained from the HAS information system.</p> <p>Results</p> <p>We found markedly reduced access to health services in the peripheral mountainous areas compared to the central plains. The quality of services was more deficient and the coverage of key services was lower in the mountains. Finally, health status, as measured by under-five mortality rates and levels of childhood malnutrition, was also worse in the mountains.</p> <p>Conclusion</p> <p>These findings indicate that local health programs need to give attention to monitoring the health status as well as the quality and coverage of basic services among marginalized groups within the program service area. Health inequities will not be overcome until such monitoring occurs and leaders of health programs ensure that inequities identified are addressed in the local programming of activities. It is quite likely that, within relatively small geographic areas in resource-poor settings around the world, similar, if not even greater, levels of health inequities exist. These inequities need to be measured and addressed in order for health programs to achieve equity and maximum improvement in health status within the population.</p
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