52 research outputs found

    Seafloor character and sedimentary processes in eastern Long Island Sound and western Block Island Sound

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    Author Posting. © The Author(s), 2006. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Geo-Marine Letters 26 (2006): 59-68, doi: 10.1007/s00367-006-0016-4.Multibeam bathymetric data and seismic-reflection profiles collected in eastern Long Island and western Block Island Sounds reveal previously unrecognized glacial features and modern bedforms. Glacial features include an ice-sculptured bedrock surface, a newly identified recessional moraine, exposed glaciolacustrine sediments, and remnants of stagnant-ice-contact deposits. Modern bedforms include fields of transverse sand waves, barchanoid waves, giant scour depressions, and pockmarks. Bedform asymmetry and scour around obstructions indicate that net sediment transport is westward across the northern par of the study area near Fishers Island and eastward across the southern par near Great Gull Island.This work was supported by the Coastal and Marine Geology Program of the U.S. Geological Survey, the Connecticut Department of Environmental Protection, and the Atlantic Hydrographic Branch of the National Oceanic and Atmospheric Administration

    Complete Genome Sequence of Treponema paraluiscuniculi, Strain Cuniculi A: The Loss of Infectivity to Humans Is Associated with Genome Decay

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    Treponema paraluiscuniculi is the causative agent of rabbit venereal spirochetosis. It is not infectious to humans, although its genome structure is very closely related to other pathogenic Treponema species including Treponema pallidum subspecies pallidum, the etiological agent of syphilis. In this study, the genome sequence of Treponema paraluiscuniculi, strain Cuniculi A, was determined by a combination of several high-throughput sequencing strategies. Whereas the overall size (1,133,390 bp), arrangement, and gene content of the Cuniculi A genome closely resembled those of the T. pallidum genome, the T. paraluiscuniculi genome contained a markedly higher number of pseudogenes and gene fragments (51). In addition to pseudogenes, 33 divergent genes were also found in the T. paraluiscuniculi genome. A set of 32 (out of 84) affected genes encoded proteins of known or predicted function in the Nichols genome. These proteins included virulence factors, gene regulators and components of DNA repair and recombination. The majority (52 or 61.9%) of the Cuniculi A pseudogenes and divergent genes were of unknown function. Our results indicate that T. paraluiscuniculi has evolved from a T. pallidum-like ancestor and adapted to a specialized host-associated niche (rabbits) during loss of infectivity to humans. The genes that are inactivated or altered in T. paraluiscuniculi are candidates for virulence factors important in the infectivity and pathogenesis of T. pallidum subspecies

    Enhancing Production of Bio-Isoprene Using Hybrid MVA Pathway and Isoprene Synthase in E. coli

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    The depleting petroleum reserve, increasingly severe energy crisis, and global climate change are reigniting enthusiasm for seeking sustainable technologies to replace petroleum as a source of fuel and chemicals. In this paper, the efficiency of the MVA pathway on isoprene production has been improved as follows: firstly, in order to increase MVA production, the source of the “upper pathway” which contains HMG-CoA synthase, acetyl-CoA acetyltransferase and HMG-CoA reductase to covert acetyl-CoA into MVA has been changed from Saccharomyces cerevisiae to Enterococcus faecalis; secondly, to further enhance the production of MVA and isoprene, a alanine 110 of the mvaS gene has been mutated to a glycine. The final genetic strain YJM25 containing the optimized MVA pathway and isoprene synthase from Populus alba can accumulate isoprene up to 6.3 g/L after 40 h of fed-batch cultivation

    Prevalence of Influenza A viruses in wild migratory birds in Alaska: Patterns of variation in detection at a crossroads of intercontinental flyways

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    <p>Abstract</p> <p>Background</p> <p>The global spread of the highly pathogenic avian influenza H5N1 virus has stimulated interest in a better understanding of the mechanisms of H5N1 dispersal, including the potential role of migratory birds as carriers. Although wild birds have been found dead during H5N1 outbreaks, evidence suggests that others have survived natural infections, and recent studies have shown several species of ducks capable of surviving experimental inoculations of H5N1 and shedding virus. To investigate the possibility of migratory birds as a means of H5N1 dispersal into North America, we monitored for the virus in a surveillance program based on the risk that wild birds may carry the virus from Asia.</p> <p>Results</p> <p>Of 16,797 birds sampled in Alaska between May 2006 and March 2007, low pathogenic avian influenza viruses were detected in 1.7% by rRT-PCR but no highly pathogenic viruses were found. Our data suggest that prevalence varied among sampling locations, species (highest in waterfowl, lowest in passerines), ages (juveniles higher than adults), sexes (males higher than females), date (highest in autumn), and analytical technique (rRT-PCR prevalence = 1.7%; virus isolation prevalence = 1.5%).</p> <p>Conclusion</p> <p>The prevalence of low pathogenic avian influenza viruses isolated from wild birds depends on biological, temporal, and geographical factors, as well as testing methods. Future studies should control for, or sample across, these sources of variation to allow direct comparison of prevalence rates.</p

    Influence of nutrients and currents on the genomic composition of microbes across an upwelling mosaic

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    Metagenomic data sets were generated from samples collected along a coastal to open ocean transect between Southern California Bight and California Current waters during a seasonal upwelling event, providing an opportunity to examine the impact of episodic pulses of cold nutrient-rich water into surface ocean microbial communities. The data set consists of ∼5.8 million predicted proteins across seven sites, from three different size classes: 0.1–0.8, 0.8–3.0 and 3.0–200.0 μm. Taxonomic and metabolic analyses suggest that sequences from the 0.1–0.8 μm size class correlated with their position along the upwelling mosaic. However, taxonomic profiles of bacteria from the larger size classes (0.8–200 μm) were less constrained by habitat and characterized by an increase in Cyanobacteria, Bacteroidetes, Flavobacteria and double-stranded DNA viral sequences. Functional annotation of transmembrane proteins indicate that sites comprised of organisms with small genomes have an enrichment of transporters with substrate specificities for amino acids, iron and cadmium, whereas organisms with larger genomes have a higher percentage of transporters for ammonium and potassium. Eukaryotic-type glutamine synthetase (GS) II proteins were identified and taxonomically classified as viral, most closely related to the GSII in Mimivirus, suggesting that marine Mimivirus-like particles may have played a role in the transfer of GSII gene functions. Additionally, a Planctomycete bloom was sampled from one upwelling site providing a rare opportunity to assess the genomic composition of a marine Planctomycete population. The significant correlations observed between genomic properties, community structure and nutrient availability provide insights into habitat-driven dynamics among oligotrophic versus upwelled marine waters adjoining each other spatially

    The effects of precision teaching and self-regulation learning on early multiplication fluency

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    Fluent recall of basic facts is essential to the development of more complex math skills. Therefore, failure to develop fluency with basic facts may impede the development of these skills. The present study used a between groups experimental design to investigate whether a basic facts fluency program, implemented within a self-regulated learner (SRL) framework, could lead to increased fluency with multiplication facts for Year 5 and Year 6 New Zealand students (9–10 years old). This study also investigated the extent to which the SRL program altered students’ basic facts practice behavior outside of school hours. The study found that the SRL program resulted in rapid fluency development that was maintained over time. Nomothetic and idiographic analysis confirmed that the program was suitable for use within Tier 1 of the response to intervention framework. In addition, the study also found that students who received the program altered their practice behavior outside school hours. The results from this study show how elements of self-regulated learning and precision teaching can be successfully combined to enhance students’ mathematics achievement

    Demographic and socioeconomic factors influencing disparities in prevalence of alcohol-related injury among underserved trauma patients in a safety-net hospital

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    Background Alcohol-related trauma remains high among underserved patients despite ongoing preventive measures. Geographic variability in prevalence of alcohol-related injury has prompted reexamination of this burden across different regions. We sought to elucidate demographic and socioeconomic factors influencing the prevalence of alcohol-related trauma among underserved patients and determine alcohol effects on selected outcomes. Methods A retrospective analysis examined whether patients admitted to a suburban trauma center differed according to their blood alcohol concentration (BAC) on admission. Patients were stratified based on their BAC into four categories (undetectable BAC, BAC 1–99 mg/dL, BAC 100–199 mg/dL, and BAC ≥ 200 mg/dL). T-tests and X2 tests were used to detect differences between BAC categories in terms of patient demographics and clinical outcomes. Multivariate linear and logistic regressions were used to investigate the association between patient variables and selected outcomes while controlling for confounders. Results One third of 738 patients analyzed were BAC-positive, mean (SD) BAC was 211.4 (118.9) mg/dL, 80% of BAC-positive patients had levels ≥ 100 mg/dL. After risk adjustments, the following patient characteristics were predictive of having highly elevated BAC (≥ 200 mg/dL) upon admission to the Trauma Center; Hispanic patients (adjusted odds ratio (OR) = 1.91, 95% confidence interval (CI): 1.14–3.21), unemployment (OR = 1.74, 95% CI: 1.09–2.78), Medicaid beneficiaries (OR = 3.59, 95% CI: 1.96–6.59), and uninsured patients (OR = 2.86, 95% CI: 1.60–5.13). Patients with BAC of 100–199 mg/dL were likely to be more severely injured (P = 0.016) compared to undetectable-BAC patients. There was no association between being intoxicated, and being ICU–admitted or having differences in length of ICU or hospital stay. Conclusion Demographic and socioeconomic factors underlie disparities in the prevalence of alcohol-related trauma among underserved patients. These findings may guide targeted interventions toward specific populations to help reduce the burden of alcohol-related injury

    Demographic and socioeconomic factors influencing disparities in prevalence of alcohol-related injury among underserved trauma patients in a safety-net hospital

    No full text
    Background Alcohol-related trauma remains high among underserved patients despite ongoing preventive measures. Geographic variability in prevalence of alcohol-related injury has prompted reexamination of this burden across different regions. We sought to elucidate demographic and socioeconomic factors influencing the prevalence of alcohol-related trauma among underserved patients and determine alcohol effects on selected outcomes. Methods A retrospective analysis examined whether patients admitted to a suburban trauma center differed according to their blood alcohol concentration (BAC) on admission. Patients were stratified based on their BAC into four categories (undetectable BAC, BAC 1–99 mg/dL, BAC 100–199 mg/dL, and BAC ≥ 200 mg/dL). T-tests and X2 tests were used to detect differences between BAC categories in terms of patient demographics and clinical outcomes. Multivariate linear and logistic regressions were used to investigate the association between patient variables and selected outcomes while controlling for confounders. Results One third of 738 patients analyzed were BAC-positive, mean (SD) BAC was 211.4 (118.9) mg/dL, 80% of BAC-positive patients had levels ≥ 100 mg/dL. After risk adjustments, the following patient characteristics were predictive of having highly elevated BAC (≥ 200 mg/dL) upon admission to the Trauma Center; Hispanic patients (adjusted odds ratio (OR) = 1.91, 95% confidence interval (CI): 1.14–3.21), unemployment (OR = 1.74, 95% CI: 1.09–2.78), Medicaid beneficiaries (OR = 3.59, 95% CI: 1.96–6.59), and uninsured patients (OR = 2.86, 95% CI: 1.60–5.13). Patients with BAC of 100–199 mg/dL were likely to be more severely injured (P = 0.016) compared to undetectable-BAC patients. There was no association between being intoxicated, and being ICU–admitted or having differences in length of ICU or hospital stay. Conclusion Demographic and socioeconomic factors underlie disparities in the prevalence of alcohol-related trauma among underserved patients. These findings may guide targeted interventions toward specific populations to help reduce the burden of alcohol-related injury
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