139 research outputs found

    Low temperature reduction of hexavalent chromium by a microbial enrichment consortium and a novel strain of Arthrobacter aurescens

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    BACKGROUND: Chromium is a transition metal most commonly found in the environment in its trivalent [Cr(III)] and hexavalent [Cr(VI)] forms. The EPA maximum total chromium contaminant level for drinking water is 0.1 mg/l (0.1 ppm). Many water sources, especially underground sources, are at low temperatures (less than or equal to 15 Centigrade) year round. It is important to evaluate the possibility of microbial remediation of Cr(VI) contamination using microorganisms adapted to these low temperatures (psychrophiles). RESULTS: Core samples obtained from a Cr(VI) contaminated aquifer at the Hanford facility in Washington were enriched in Vogel Bonner medium at 10 Centigrade with 0, 25, 50, 100, 200, 400 and 1000 mg/l Cr(VI). The extent of Cr(VI) reduction was evaluated using the diphenyl carbazide assay. Resistance to Cr(VI) up to and including 1000 mg/l Cr(VI) was observed in the consortium experiments. Reduction was slow or not observed at and above 100 mg/l Cr(VI) using the enrichment consortium. Average time to complete reduction of Cr(VI) in the 30 and 60 mg/l Cr(VI) cultures of the consortium was 8 and 17 days, respectively at 10 Centigrade. Lyophilized consortium cells did not demonstrate adsorption of Cr(VI) over a 24 hour period. Successful isolation of a Cr(VI) reducing organism (designated P4) from the consortium was confirmed by 16S rDNA amplification and sequencing. Average time to complete reduction of Cr(VI) at 10 Centigrade in the 25 and 50 mg/l Cr(VI) cultures of the isolate P4 was 3 and 5 days, respectively. The 16S rDNA sequence from isolate P4 identified this organism as a strain of Arthrobacter aurescens, a species that has not previously been shown to be capable of low temperature Cr(VI) reduction. CONCLUSION: A. aurescens, indigenous to the subsurface, has the potential to be a predominant metal reducer in enhanced, in situ subsurface bioremediation efforts involving Cr(VI) and possibly other heavy metals and radionuclides

    Biomass Blending and Densification: Impacts on Feedstock Supply and Biochemical Conversion Performance

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    The success of lignocellulosic biofuels and biochemical industries depends on an economic and reliable supply of high‐quality biomass. However, research and development efforts have been historically focused on the utilization of agriculturally derived cellulosic feedstocks, without considerations of their low energy density, high variations in compositions and potential supply risks in terms of availability and affordability. This chapter demonstrated a strategy of feedstock blending and densification to address the supply chain challenges. Blending takes advantage of low‐cost feedstock to avoid the prohibitive costs incurred through reliance on a single feedstock resource, while densification produces feedstocks with increased bulk density and desirable feed handling properties, as well as reduced transportation cost. We also review recent research on the blending and densification dealing with various types of feedstocks with a focus on the impacts of these preprocessing steps on biochemical conversion, that is, various thermochemical pretreatment chemistries and enzymatic hydrolysis, into fermentable sugars for biofuel production

    Self-rated health and health care access associated with African American men’s health self-efficacy

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    Health self-efficacy, a measure of one’s self-assurance in taking care of their own health, is known to contribute to a range of health outcomes that has been under examined among African American men. The purpose of this investigation was to identify and contextualize predictors of general health self-efficacy in this population. A cross-sectional sample of surveys from 558 African American was examined. These men were older than 18 years, could read and write English, and attended a hospital-based community health fair targeting minority men in 2011. The outcome of interest was health self-efficacy, which was assessed by asking, “Overall, how confident are you in your ability to take good care of your health?” Responses ranged from 1 (not confident at all) to 5 (completely confident). Covariates included age, self-rated health, health insurance status, having a regular physician, and being a smoker. The mean age of participants was 54.4 years, and 61.3% of participants indicated confidence in their ability to take good care of their health. Older age and being a smoker were inversely associated with the outcome. Good self-rated health, having health insurance, and having a regular doctor were positively associated with reports of health self-efficacy. Findings suggest that multiple points of connection to the health care system increase the likelihood of health self-efficacy for this sample and interventions to support older African American men who may evaluate their own health status as poor and who may face barriers to health care access are implicated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/164711/1/Thompson et al 2017 Self-rated health and health care access.pdfDescription of Thompson et al 2017 Self-rated health and health care access.pdf : Main articl

    Nature: a new paradigm for well-being and ergonomics

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    Nature is presented as a new paradigm for ergonomics. As a discipline concerned with well-being, the importance of natural environments for wellness should be part of ergonomics knowledge and practice. This position is supported by providing a concise summary of the evidence of the value of the natural environment to well-being. Further, an emerging body of research has found relationships between well-being and a connection to nature, a concept that reveals the integrative character of human experience which can inform wider practice and epistemology in ergonomics. Practitioners are encouraged to bring nature into the workplace, so that ergonomics keeps pace with the move to nature-based solutions, but also as a necessity in the current ecological and social context. Practitioner Summary: Nature-based solutions are coming to the fore to address societal challenges such as well-being. As ergonomics is concerned with well-being, there is a need for a paradigm shift in the discipline. This position is supported by providing a concise summary of the evidence of the value of the natural environment to well-being

    Effects of Eyjafjallajökull volcanic ash on innate immune system responses and bacterial growth in vitro.

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    To access publisher's full text version of this article click on the hyperlink at the bottom of the pageOn 20 March 2010, the Icelandic volcano Eyjafjallajökull erupted for the first time in 190 years. Despite many epidemiological reports showing effects of volcanic ash on the respiratory system, there are limited data evaluating cellular mechanisms involved in the response to ash. Epidemiological studies have observed an increase in respiratory infections in subjects and populations exposed to volcanic eruptions.We physicochemically characterized volcanic ash, finding various sizes of particles, as well as the presence of several transition metals, including iron. We examined the effect of Eyjafjallajökull ash on primary rat alveolar epithelial cells and human airway epithelial cells (20-100 µg/cm(2)), primary rat and human alveolar macrophages (5-20 µg/cm(2)), and Pseudomonas aeruginosa (PAO1) growth (3 µg/104 bacteria).Volcanic ash had minimal effect on alveolar and airway epithelial cell integrity. In alveolar macrophages, volcanic ash disrupted pathogen-killing and inflammatory responses. In in vitro bacterial growth models, volcanic ash increased bacterial replication and decreased bacterial killing by antimicrobial peptides.These results provide potential biological plausibility for epidemiological data that show an association between air pollution exposure and the development of respiratory infections. These data suggest that volcanic ash exposure, while not seriously compromising lung cell function, may be able to impair innate immunity responses in exposed individuals.National Institutes of Health (NIH) R01 HL079901 NIH RO1 HL096625 R21HL109589 National Science Foundation NSF-EAR0821615 National Institute of Environmental Health Sciences (NIEHS) through the University of Iowa Environmental Health Sciences Research Center NIEHS/NIH P30 ES005605 National Center for Research Resources, NI

    A novel ESR2 frameshift mutation predisposes to medullary thyroid carcinoma and causes inappropriate RET expression

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    Investigation of rheumatoid arthritis susceptibility loci in juvenile idiopathic arthritis confirms high degree of overlap

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    <p>Objectives: Rheumatoid arthritis (RA) shares some similar clinical and pathological features with juvenile idiopathic arthritis (JIA); indeed, the strategy of investigating whether RA susceptibility loci also confer susceptibility to JIA has already proved highly successful in identifying novel JIA loci. A plethora of newly validated RA loci has been reported in the past year. Therefore, the aim of this study was to investigate these single nucleotide polymorphisms (SNP) to determine if they were also associated with JIA.</p> <p>Methods: Thirty-four SNP that showed validated association with RA and had not been investigated previously in the UK JIA cohort were genotyped in JIA cases (n=1242), healthy controls (n=4281), and data were extracted for approximately 5380 UK Caucasian controls from the Wellcome Trust Case–Control Consortium 2. Genotype and allele frequencies were compared between cases with JIA and controls using PLINK. A replication cohort of 813 JIA cases and 3058 controls from the USA was available for validation of any significant findings.</p> <p>Results: Thirteen SNP showed significant association (p<0.05) with JIA and for all but one the direction of association was the same as in RA. Of the eight loci that were tested, three showed significant association in the US cohort.</p> <p>Conclusions: A novel JIA susceptibility locus was identified, CD247, which represents another JIA susceptibility gene whose protein product is important in T-cell activation and signalling. The authors have also confirmed association of the PTPN2 and IL2RA genes with JIA, both reaching genome-wide significance in the combined analysis.</p&gt

    Proceedings of the Sixth Caldwell Conference, St. Catherines Island, Georgia, May 20-22, 2011.

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    494 pages : illustrations (some color), maps (some color) ; 26 cm. Conference sponsored by the American Museum of Natural History and the St. Catherines Island Foundation.Although this volume covers a broad range of temporal and methodological topics, the chapters are unified by a geographic focus on the archaeology of the Georgia Bight. The various research projects span multiple time periods (including Archaic, Woodland, Mississippian, and contact periods) and many incorporate specialized analyses (such as petrographic point counting, shallow geophysics, and so forth). The 26 contributors conducting this cutting-edge work represent the full spectrum of the archaeological community, including museum, academic, student, and contract archaeologists. Despite the diversity in professional and theoretical backgrounds, temporal periods examined, and methodological approaches pursued, the volume is unified by four distinct, yet interrelated, themes. Contributions in Part I discuss a range of analytical approaches for understanding time, exchange, and site layout. Chapters in Part II model coastal landscapes from both environmental and social perspectives. The third section addresses site-specific studies of late prehistoric architecture and village layout throughout the Georgia Bight. Part IV presents new and ongoing research into the Spanish mission period of this area. These papers were initially presented and discussed at the Sixth Caldwell Conference, cosponsored by the American Museum of Natural History and the St. Catherines Island Foundation, held on St. Catherines Island, Georgia, May 20-22, 2011. TABLE OF CONTENTS: Revising the ¹⁴C reservoir correction for St. Catherines Island, Georgia / David Hurst Thomas, Matthew C. Sanger, and Royce H. Hayes -- An assessment of coastal faunal data from Georgia and northeast Florida / Alexandra L. Parsons and Rochelle A. Marrinan -- Archaeological geophysics on St. Catherines Island : beyond prospection / Ginessa J. Mahar -- Paste variability and clay resource utilization at the Fountain of Youth site, St. Augustine, 8SJ31 / Ann S. Cordell and Kathleen A. Deagan -- Petrographic analysis of pottery and clay samples from the Georgia Bight : evidence of regional social interactions / Neill J. Wallis and Ann S. Cordell -- Past shorelines of the Georgia coast / Chester B. DePratter and Victor D. Thompson -- Coastal landscapes and their relationship to human settlement on the Georgia coast / John A. Turck and Clark R. Alexander -- The role of small islands in foraging economies of St. Catherines Island / Matthew F. Napolitano -- Ever-shifting landscapes : tracking changing spatial usage along coastal Georgia / Matthew C. Sanger -- A paleoeconomic model of the Georgia coast (4500-300 B.P.) / Thomas G. Whitley -- A survey of Irene phase architecture on the Georgia coast / Deborah A. Keene and Ervan G. Garrison -- Life and death on the Ogeechee : a view from the Redbird Creek village / Ryan O. Sipe -- Mission San Joseph de Sapala : mission-period archaeological research on Sapelo Island / Richard W. Jefferies and Christopher R. Moore -- The Guale landscape of Mission Santa Catalina de Guale : 30 years of geophysics at a Spanish colonial mission / Elliot H. Blair -- Missions San Buenaventura and Santa Cruz de Guadalquini : retreat from the Georgia coast / Keith H. Ashley, Vicki L. Rolland, and Robert L. Thunen -- Entangling events : the Guale coastal landscape and the Spanish missions / Victor D. Thompson, John A. Turck, Amanda D. Roberts Thompson, and Chester B. DePratter -- Island and coastal archaeology on the Georgia Bight / Scott M. Fitzpatrick

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

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    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio
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