1,172 research outputs found

    Description of remote control cable yarding systems and an evaluation of the Forestral Remote Control Grapple Yarding System

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    Political Information Flow and Management Guidance

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    We examine whether politically active firms play a role in disseminating political information via their management guidance. Using campaign financing activity or the presence of a government affairs office to proxy for firms’ access to political information, we find that politically active firms are more likely to issue management guidance overall, and especially when the government is a customer of the firm. Further, relative to politically inactive firms, the guidance released by politically active firms is more likely to discuss government policies. In addition to using numerous econometric techniques to address self-selection, we examine the timing of when guidance is issued. We find that politically active firms are more likely to issue guidance and change their government policy-related disclosures prior to the public revelation of government policy decisions. Collectively, these findings suggest that the privileged information firms obtain through their political activities is shared with investors through voluntary disclosures

    Association of BCG, DTP, and measles containing vaccines with childhood mortality:systematic review

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    Objectives To evaluate the effects on non-specific and all cause mortality, in children under 5, of Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP), and standard titre measles containing vaccines (MCV); to examine internal validity of the studies; and to examine any modifying effects of sex, age, vaccine sequence, and co-administration of vitamin A. Design Systematic review, including assessment of risk of bias, and meta-analyses of similar studies. Study eligibility criteria Clinical trials, cohort studies, and case-control studies of the effects on mortality of BCG, whole cell DTP, and standard titre MCV in children under 5. Data sources Searches of Medline, Embase, Global Index Medicus, and the WHO International Clinical Trials Registry Platform, supplemented by contact with experts in the field. To avoid overlap in children studied across the included articles, findings from non-overlapping birth cohorts were identified. Results Results from 34 birth cohorts were identified. Most evidence was from observational studies, with some from short term clinical trials. Most studies reported on all cause (rather than non-specific) mortality. Receipt of BCG vaccine was associated with a reduction in all cause mortality: the average relative risks were 0.70 (95% confidence interval 0.49 to 1.01) from five clinical trials and 0.47 (0.32 to 0.69) from nine observational studies at high risk of bias. Receipt of DTP (almost always with oral polio vaccine) was associated with a possible increase in all cause mortality on average (relative risk 1.38, 0.92 to 2.08) from 10 studies at high risk of bias; this effect seemed stronger in girls than in boys. Receipt of standard titre MCV was associated with a reduction in all cause mortality (relative risks 0.74 (0.51 to 1.07) from four clinical trials and 0.51 (0.42 to 0.63) from 18 observational studies at high risk of bias); this effect seemed stronger in girls than in boys. Seven observational studies, assessed as being at high risk of bias, have compared sequences of vaccines; results of a subset of these suggest that administering DTP with or after MCV may be associated with higher mortality than administering it before MCV. Conclusions Evidence suggests that receipt of BCG and MCV reduce overall mortality by more than would be expected through their effects on the diseases they prevent, and receipt of DTP may be associated with an increase in all cause mortality. Although efforts should be made to ensure that all children are immunised on schedule with BCG, DTP, and MCV, randomised trials are needed to compare the effects of different sequences

    Source-Specific Air Pollution Including Ultrafine Particles and Risk of Myocardial Infarction:A Nationwide Cohort Study from Denmark

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    BACKGROUND: Air pollution is negatively associated with cardiovascular health. Impediments to efficient regulation include lack of knowledge about which sources of air pollution contributes most to health burden and few studies on effects of the potentially more potent ultrafine particles (UFP). OBJECTIVE: The authors aimed to investigate myocardial infarction (MI) morbidity and specific types and sources of air pollution. METHODS: We identified all persons living in Denmark in the period 2005–2017, age &gt;50 y and never diagnosed with MI. We quantified 5-y running time-weighted mean concentrations of air pollution at residencies, both total and apportioned to traffic and nontraffic sources. We evaluated particulate matter (PM) with aerodynamic diameter ≀2:5 lm (PM 2:5), &lt;0:1 lm (UFP), elemental carbon (EC), and nitrogen dioxide (NO 2). We used Cox pro-portional hazards models, with adjustment for time-varying exposures, and personal and area-level demographic and socioeconomic covariates from high-quality administrative registers. RESULTS: In this nationwide cohort of 1,964,702 persons (with 18 million person-years of follow-up and 71,285 cases of MI), UFP and PM 2:5 were associated with increased risk of MI with hazard ratios (HRs) per interquartile range (IQR) of 1.040 [95% confidence interval (CI): 1.025, 1.055] and 1.053 (95% CI: 1.035, 1.071), respectively. HRs per IQR of UFP and PM 2:5 from nontraffic sources were similar to the total (1.034 and 1.051), whereas HRs for UFP and PM 2:5 from traffic sources were smaller (1.011 and 1.011). The HR for EC from traffic sources was 1.013 (95% CI: 1.003, 1.023). NO 2 from nontraffic sources was associated with MI (HR = 1:048; 95% CI: 1.034, 1.062) but not from traffic sources. In general, nontraffic sources contributed more to total air pollution levels than national traffic sources. CONCLUSIONS: PM 2:5 and UFP from traffic and nontraffic sources were associated with increased risk of MI, with nontraffic sources being the domi-nant source of exposure and morbidity. https://doi.org/10.1289/EHP10556.</p

    Impact of Systematic Errors in Sunyaev-Zel'dovich Surveys of Galaxy Clusters

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    Future high-resolution microwave background measurements hold the promise of detecting galaxy clusters throughout our Hubble volume through their Sunyaev-Zel'dovich (SZ) signature, down to a given limiting flux. The number density of galaxy clusters is highly sensitive to cluster mass through fluctuations in the matter power spectrum, as well as redshift through the comoving volume and the growth factor. This sensitivity in principle allows tight constraints on such quantities as the equation of state of dark energy and the neutrino mass. We evaluate the ability of future cluster surveys to measure these quantities simultaneously when combined with PLANCK-like CMB data. Using a simple effective model for uncertainties in the cluster mass-SZ flux relation, we evaluate systematic shifts in cosmological constraints from cluster SZ surveys. We find that a systematic bias of 10% in cluster mass measurements can give rise to shifts in cosmological parameter estimates at levels larger than the 1σ1\sigma statistical errors. Systematic errors are unlikely to be detected from the mass and redshift dependence of cluster number counts alone; increasing survey size has only a marginal effect. Implications for upcoming experiments are discussed.Comment: 12 pages, 6 figures; accepted to JCAP; revised to match submitted versio

    Residential exposure to PM<sub>2.5</sub> components and risk of childhood non-hodgkin lymphoma in Denmark:A nationwide register-based case-control study

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    In a recent study, we observed an increased risk of childhood non-Hodgkin lymphoma (NHL) associated with exposure to fine atmospheric particulate matter (PM2.5) and black carbon (BC). In this nationwide register-based case-control study, we focus on specific components of PM2.5 in relation to childhood NHL in Denmark (1981–2013) by identifying all incidents of childhood NHL cases in the Danish Cancer Registry (n = 170) and four (cancer-free) randomly selected controls matched by date of birth and sex. We applied PM2.5 concentrations and the following sub-components: secondary organic aerosols (SOA), secondary inorganic aerosols (SIA; i.e., NO3−, NH4+ and SO42−), BC, organic carbon (OC) and sea salt. We calculated a time-weighted exposure average from birth to index-date at all addresses. Odds ratios (ORs) were adjusted for register-based socio-demographic variables. We observed adjusted ORs and 95% confidence intervals (95% CI) of 2.05 (1.10, 3.83) per interquartile range (IQR, 4.83 ”g/m3) PM2.5 and 1.73 (0.68, 4.41) per IQR (3.71 ”g/m3) SIA, 0.95 (0.71, 1.29) per IQR (0.05 ”g/m3) SOA, 1.22 (1.02, 1.46) per IQR (0.39 ”g/m3) BC, 1.02 (0.83, 1.26) per IQR (0.56 ”g/m3) OC and 1.01 (0.79, 1.30) per IQR (0.87 ”g/m3) sea salt, respectively. The estimates were attenuated after adjustment for PM2.5, whereas the OR for PM2.5 remained increased regardless of adjustment for specific components. The findings indicate that the previously observed relation between PM2.5 and childhood NHL may be related to BC (as reported in our previous study) but also partly to SIA, but the role of specific chemical components of PM2.5 remains ambiguous
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