1,072 research outputs found
Particle Association of Enterococcus and Total Bacteria in the Lower Hudson River Estuary, USA
Bacterial particle association has important consequences for water-quality monitoring and modeling. Parti-cle association can change vertical and horizontal transport of bacterial cells, as well as patterns of persis-tence and production. In this study, the abundance and particle association of total bacteria and the fe-cal-indicator, Enterococcus, were quantified between June and October 2008 in the lower Hudson River Es-tuary (HRE). Twelve sites were sampled, including mid-channel, near shore, and tributary habitats, plus a sewage outfall. Total bacterial cell counts averaged 9.2 × 109 ± 6.4 × 109 cell·l–1 (1 standard deviation), com-parable to previous sampling in the HRE. Unlike earlier studies, bacterial abundance did not change consis-tently along the north/south estuarine salinity gradient. Enterococcus concentrations were highly variable, but mid-channel stations had significantly lower values than other habitat categories. Counts of total bacteria and Enterococci were both correlated with turbidity, which was also significantly lower at mid-channel sta-tions. A larger fraction of Enterococci were associated with particles (52.9% ± 20.9%, 1 standard deviation) than in the pool of total bacteria (23.8% ± 15.0%). This high frequency of particle association, relative to total bacteria, could cause Enterococci to be preferentially retained near input sources because of enhanced deposition to bottom sediments, where they would be available for later resuspension. In turn, retention and resuspension in nearshore environments may explain the observed cross-channel variability of turbidity and Enterococci. Assessments and predictive models of estuarine water quality may be improved by incorporat-ing cross-channel variability and the effects of particle association on key indicators
Academic Chemistry Inputs and Outcomes Data
The Academic Chemistry Inputs and Outcomes Data assembles panel data on academic chemistry inputs and outputs for 147 universities from 1989 through 2009. Each observation represents a single university-year and includes information on numbers of publications, citations to these publications, levels of federal and non-federal R&D funding, numbers of faculty, postdoctoral researchers, doctorates awarded and institutional characteristics. The data were compiled for the analysis of the determinants of university publication behavior and its relationship to research funding as reported in Joshua L. Rosenbloom, Donna K. Ginther, Ted Juhl and Joseph Heppert, "The Effects of Research & Development Funding on Scientific Productivity: Academic Chemistry, 1990-2009," Public Library of Science One, available in KU ScholarWorks at http://hdl.handle.net/1808/20057.
As described in the Data Description and Code Book, these data were assembled by linking together information from a number of publicly available data sources and combining them with proprietary data on publications and citations provided by Thomson Reuters from their Web of Science database.
These data are available to download as a text file (.csv) and as a STATA (.dta) data file. Anyone is free to use these data for scholarly purposes, but must include a citation to this user guide in any papers or published articles that employ these data
Maternal Recreational Exercise during Pregnancy in relation to Children's BMI at 7 Years of Age
Exposures during fetal life may have long-term health consequences including risk of childhood overweight. We investigated the associations between maternal recreational exercise during early and late pregnancy and the children's body mass index (BMI) and risk of overweight at 7 years. Data on 40,280 mother-child pairs from the Danish National Birth Cohort was used. Self-reported information about exercise was obtained from telephone interviews around gestational weeks 16 and 30. Children's weight and height were reported in a 7-year follow-up and used to calculate BMI and overweight status. Data was analyzed using multiple linear and logistic regression models. Recreational exercise across pregnancy was inversely related to children's BMI and risk of overweight, but all associations were mainly explained by smoking habits, socioeconomic status, and maternal pre-pregnancy BMI. Additionally, we did not find exercise intensity or changes in exercise habits in pregnancy related to the children's BMI or risk of overweight
Leisure time physical exercise during pregnancy and the risk of miscarriage: a study within the Danish National Birth Cohort
Justification of research using systematic reviews continues to be inconsistent in clinical health science:A systematic review and meta-analysis of meta-research studies
BACKGROUND: Redundancy is an unethical, unscientific, and costly challenge in clinical health research. There is a high risk of redundancy when existing evidence is not used to justify the research question when a new study is initiated. Therefore, the aim of this study was to synthesize meta-research studies evaluating if and how authors of clinical health research studies use systematic reviews when initiating a new study. METHODS: Seven electronic bibliographic databases were searched (final search June 2021). Meta-research studies assessing the use of systematic reviews when justifying new clinical health studies were included. Screening and data extraction were performed by two reviewers independently. The primary outcome was defined as the percentage of original studies within the included meta-research studies using systematic reviews of previous studies to justify a new study. Results were synthesized narratively and quantitatively using a random-effects meta-analysis. The protocol has been registered in Open Science Framework (https://osf.io/nw7ch/). RESULTS: Twenty-one meta-research studies were included, representing 3,621 original studies or protocols. Nineteen of the 21 studies were included in the meta-analysis. The included studies represented different disciplines and exhibited wide variability both in how the use of previous systematic reviews was assessed, and in how this was reported. The use of systematic reviews to justify new studies varied from 16% to 87%. The mean percentage of original studies using systematic reviews to justify their study was 42% (95% CI: 36% to 48%). CONCLUSION: Justification of new studies in clinical health research using systematic reviews is highly variable, and fewer than half of new clinical studies in health science were justified using a systematic review. Research redundancy is a challenge for clinical health researchers, as well as for funders, ethics committees, and journals
Systematic reviews are rarely used to contextualise new results-a systematic review and meta-analysis of meta-research studies
BACKGROUND: Results of new studies should be interpreted in the context of what is already known to compare results and build the state of the science. This systematic review and meta-analysis aimed to identify and synthesise results from meta-research studies examining if original studies within health use systematic reviews to place their results in the context of earlier, similar studies. METHODS: We searched MEDLINE (OVID), EMBASE (OVID), and the Cochrane Methodology Register for meta-research studies reporting the use of systematic reviews to place results of original clinical studies in the context of existing studies. The primary outcome was the percentage of original studies included in the meta-research studies using systematic reviews or meta-analyses placing new results in the context of existing studies. Two reviewers independently performed screening and data extraction. Data were synthesised using narrative synthesis and a random-effects meta-analysis was performed to estimate the mean proportion of original studies placing their results in the context of earlier studies. The protocol was registered in Open Science Framework. RESULTS: We included 15 meta-research studies, representing 1724 original studies. The mean percentage of original studies within these meta-research studies placing their results in the context of existing studies was 30.7% (95% CI [23.8%, 37.6%], I(2)=87.4%). Only one of the meta-research studies integrated results in a meta-analysis, while four integrated their results within a systematic review; the remaining cited or referred to a systematic review. The results of this systematic review are characterised by a high degree of heterogeneity and should be interpreted cautiously. CONCLUSION: Our systematic review demonstrates a low rate of and great variability in using systematic reviews to place new results in the context of existing studies. On average, one third of the original studies contextualised their results. Improvement is still needed in researchers’ use of prior research systematically and transparently—also known as the use of an evidence-based research approach, to contribute to the accumulation of new evidence on which future studies should be based. SYSTEMATIC REVIEW REGISTRATION: Open Science registration number https://osf.io/8gkzu/ SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13643-022-02062-8
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