4,281 research outputs found

    Locating Battery Charging Stations to Facilitate Almost Shortest Paths

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    We study a facility location problem motivated by requirements pertaining to the distribution of charging stations for electric vehicles: Place a minimum number of battery charging stations at a subset of nodes of a network, so that battery-powered electric vehicles will be able to move between destinations using "t-spanning" routes, of lengths within a factor t > 1 of the length of a shortest path, while having sufficient charging stations along the way. We give constant-factor approximation algorithms for minimizing the number of charging stations, subject to the t-spanning constraint. We study two versions of the problem, one in which the stations are required to support a single ride (to a single destination), and one in which the stations are to support multiple rides through a sequence of destinations, where the destinations are revealed one at a time

    Total Number of U.S. Statehouse Reporters Rises, but Fewer Are on the Beat Full Time

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    From voting rights and redistricting to abortion and public education, state capitols across the United States are at the epicenter of the nation's key public policy debates. This has been especially true during the COVID-19 pandemic, as state capitol buildings became ground zero in the debate over mask and vaccine mandates and other pandemic policies.A new Pew Research Center study finds that the total number of reporters assigned to the 50 state capitols to inform citizens about legislative and administrative activity has increased by 11% since 2014, the last time this study was conducted. The gain comes largely from two main developments: new nonprofit news outlets that are employing statehouse reporters, and a shift to more part-time statehouse reporting

    Service utilisation and family support of people with dementia: a cohort study in England.

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    Objectives This study aimed to compare costs of caring for people with dementia in domiciliary and residential settings, central England. Methods A cohort of people with dementia was recruited during a hospital stay 2008–2010. Data were collected by interview at baseline, and 6- and 12-month follow-up, covering living situation (own home with or without co-resident carer, care home); cognition, health status and functioning of person with dementia; carer stress; utilisation of health and social services; and informal (unpaid) caring input. Costs of formal services and informal caring (replacement cost method) were calculated. Costs of residential and domiciliary care packages were compared. Results Data for 109 people with dementia were collected at baseline; 95 (87.2%) entered hospital from their own homes. By 12 months, 40 (36.7%) had died and 85% of the survivors were living in care homes. Over one-half of people with dementia reported social care packages at baseline; those living alone had larger packages than those living with others. Median caring time for co-resident carers was 400 min/day and 10 h/week for non co-resident carers. Residential care was more costly than domiciliary social care for most people. When the value of informal caring was included, the total cost of domiciliary care was higher than residential care, but not significantly so. Carer stress reduced significantly after the person with dementia entered a care home. Conclusions Caring for people with dementia at home may be more expensive, and more stressful for carers, than care in residential settings

    Principles of Anti-infective Dosing in Pregnancy

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    AbstractPurposeAnti-infectives are among the most commonly prescribed medications in pregnancy. However, detailed information on the pharmacokinetics and pharmacodynamics of these medications in pregnancy is limited, leading to uncertainty among clinicians regarding the tolerability and efficacy of treatments. The purposes of this review were to highlight key physiologic changes during pregnancy that influence drug behavior, and to discuss areas of active research related to anti-infective drugs in pregnancy.MethodsA review of literature in PubMed was performed for topics related to physiologic changes of pregnancy, postcesarean surgical site infections, vaccines in pregnancy, and intrauterine infections. The literature was reviewed and pertinent sources were utilized for this article.FindingsPhysiologic changes during pregnancy may impact drug disposition and efficacy. Cefazolin regimens are the current prophylactic treatment of choice for postcesarean surgical site infections. Vaccines are provided in pregnancy for both maternal and neonatal benefit. Broad-spectrum antibiotics continue to be used as first-line therapy for intrauterine infections.ImplicationsContinued efforts to broaden the knowledge base on anti-infective drug behavior in pregnancy will result in increased therapeutic options for this population

    Network Optimization on Partitioned Pairs of Points

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    Given n pairs of points, S = {{p_1, q_1}, {p_2, q_2}, ..., {p_n, q_n}}, in some metric space, we study the problem of two-coloring the points within each pair, red and blue, to optimize the cost of a pair of node-disjoint networks, one over the red points and one over the blue points. In this paper we consider our network structures to be spanning trees, traveling salesman tours or matchings. We consider several different weight functions computed over the network structures induced, as well as several different objective functions. We show that some of these problems are NP-hard, and provide constant factor approximation algorithms in all cases

    Psychosocial interventions for patients with head and neck cancer.

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    BACKGROUND: A diagnosis of head and neck cancer, like many other cancers, can lead to significant psychosocial distress. Patients with head and neck cancer can have very specific needs, due to both the location of their disease and the impact of treatment, which can interfere with basic day-to-day activities such as eating, speaking and breathing. There is a lack of clarity on the effectiveness of the interventions developed to address the psychosocial distress experienced by patients living with head and neck cancer. OBJECTIVES: To assess the effectiveness of psychosocial interventions to improve quality of life and psychosocial well-being for patients with head and neck cancer. SEARCH METHODS: We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ICTRP and additional sources for published and unpublished trials. The date of the most recent search was 17 December 2012. SELECTION CRITERIA: We selected randomised controlled trials and quasi-randomised controlled trials of psychosocial interventions for adults with head and neck cancer. For trials to be included the psychosocial intervention had to involve a supportive relationship between a trained helper and individuals diagnosed with head and neck cancer. Outcomes had to be assessed using a validated quality of life or psychological distress measure, or both. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials, extracted data and assessed the risk of bias, with mediation from a third author where required. Where possible, we extracted outcome measures for combining in meta-analyses. We compared continuous outcomes using either mean differences (MD) or standardised mean differences (SMD) and 95% confidence intervals (CI), with a random-effects model. We conducted meta-analyses for the primary outcome measure of quality of life and secondary outcome measures of psychological distress, including anxiety and depression. We subjected the remaining outcome measures (self esteem, coping, adjustment to cancer, body image) to a narrative synthesis, due to the limited number of studies evaluating these specific outcomes and the wide divergence of assessment tools used. MAIN RESULTS: Seven trials, totaling 542 participants, met the eligibility criteria. Studies varied widely on risk of bias, interventions used and outcome measures reported. From these studies, there was no evidence to suggest that psychosocial intervention promotes global quality of life for patients with head and neck cancer at end of intervention (MD 1.23, 95% CI -5.82 to 8.27) as measured by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). This quality of life tool includes five functional scales, namely cognitive, physical, emotional, social and role. There was no evidence to demonstrate that psychosocial intervention provides an immediate or medium-term improvement on any of these five functional scales. From the data available, there was no significant change in levels of anxiety (SMD -0.09, 95% CI -0.40 to 0.23) or depression following intervention (SMD -0.03, 95% CI -0.24 to 0.19). At present, there is insufficient evidence to refute or support the effectiveness of psychosocial intervention for patients with head and neck cancer. AUTHORS' CONCLUSIONS: The evidence for psychosocial intervention is limited by the small number of studies, methodological shortcomings such as lack of power, difficulties with comparability between types of interventions and a wide divergence in outcome measures used. Future research should be targeted at patients who screen positive for distress and use validated outcome measures, such as the EORTC scale, as a measure of quality of life. These studies should implement interventions that are theoretically derived. Other shortcomings should be addressed in future studies, including using power calculations that may encourage multi-centred collaboration to ensure adequate sample sizes are recruited

    Simulating the diversity of shapes of the Lyman-α\alpha line

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    The Lyα\alpha line is a powerful probe of distant galaxies, which contains information about inflowing/outflowing gas through which Lyα\alpha photons scatter. To develop our understanding of this probe, we post-process a zoom-in radiation-hydrodynamics simulation of a low-mass (M109MM_* \sim 10^9 M_\odot) galaxy to construct 22500 mock spectra in 300 directions from z=3z = 3 to 4. Remarkably, we show that one galaxy can reproduce the variety of a large sample of spectroscopically observed Lyα\alpha line profiles. While most mock spectra exhibit double-peak profiles with a dominant red peak, their shapes cover a large parameter space in terms of peak velocities, peak separation and flux ratio. This diversity originates from radiative transfer effects at ISM and CGM scales, and depends on galaxy inclination and evolutionary phase. Red-dominated lines preferentially arise in face-on directions during post-starburst outflows and are bright. Conversely, accretion phases usually yield symmetric double peaks in the edge-on direction and are fainter. While resonant scattering effects at <0.2×Rvir< 0.2\times R_{\rm vir} are responsible for the broadening and velocity shift of the red peak, the extended CGM acts as a screen and impacts the observed peak separation. The ability of simulations to reproduce observed Lyα\alpha profiles and link their properties with galaxy physical parameters offers new perspectives to use Lyα\alpha to constrain the mechanisms that regulate galaxy formation and evolution. Notably, our study implies that deeper Lyα\alpha surveys may unveil a new population of blue-dominated lines tracing inflowing gas.Comment: Accepted for publication in MNRA

    The 2016 Academic Emergency Medicine Consensus Conference, Shared Decision Making in the Emergency Department: Development of a Policy-relevant Patient-centered Research Agenda Diagnostic Testing Breakout Session Report.

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    Diagnostic testing is an integral component of patient evaluation in the emergency department (ED). Emergency clinicians frequently use diagnostic testing to more confidently exclude worst-case diagnoses rather than to determine the most likely etiology for a presenting complaint. Increased utilization of diagnostic testing has not been associated with reductions in disease-related mortality but has led to increased overall healthcare costs and other unintended consequences (e.g., incidental findings requiring further workup, unnecessary exposure to ionizing radiation or potentially nephrotoxic contrast). Shared decision making (SDM) presents an opportunity for clinicians to discuss the benefits and harms associated with diagnostic testing with patients to more closely tailor testing to patient risk. This article introduces the challenges and opportunities associated with incorporating SDM into emergency care by summarizing the conclusions of the diagnostic testing group at the 2016 Academic Emergency Medicine Consensus Conference on SDM. Three primary domains emerged: 1) characteristics of a condition or test appropriate for SDM, 2) critical elements of and potential barriers to SDM discussions on diagnostic testing, and 3) financial aspects of SDM applied to diagnostic testing. The most critical research questions to improve engagement of patients in their acute care diagnostic decisions were determined by consensus

    The differential effects of concurrent planning practice elements on reunification and adoption

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    Objective: The child welfare practice of concurrent planning attempts to shorten children\u27s stays in foster care. There is very little quantitative research on concurrent planning\u27s effects. This study examines the influence of concurrent planning practice elements (reunification prognosis, concurrent plan, full disclosure, and discussion of voluntary relinquishment) on reunification and adoption. Method: Using a sample of 885 children, an observational design, and statistical controls, children who received concurrent planning elements were compared to those who did not. Results: Findings show discussion of voluntary relinquishment to be positively associated with adoption and full disclosure to be negatively associated with reunification. Conclusions: Concurrent planning\u27s benefits may require more intensive services to be fully realized. Care should be taken to ensure activities achieve their intended effects
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