405 research outputs found

    The Effect of Spill Contaminants on Marine Biofilms and Microbially-Induced Corrosion of Carbon Steel

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    There are over 2,000 known historic shipwrecks located in the northern Gulf of Mexico which are ecological and cultural resources that support the diversity of life found in the deep-sea when they become artificial reefs. Spilled crude oil and chemical dispersant from the Deepwater Horizon (DWH) spill may have impacted the preservation of deep-sea historic shipwrecks and their microbiomes if they are located in areas where oil and dispersant were deposited on the seafloor. Oil potentially accelerates corrosion of metal through a biologically-mediated process called microbially-induced corrosion (MIC). Introduction of spill contaminants may accelerate MIC on shipwreck hulls, which may place the integrity of historic shipwrecks at risk. The effects of this process can be studied through laboratory and field experiments to provide understanding of the biofilm formation and metal corrosion processes under oiled and un-oiled scenarios. Elucidating the mechanisms of MIC through metagenomics will help fill the knowledge gap of the interaction between abiotic corrosion and biologically-mediated processes that potentially accelerate corrosion on metal surfaces. Results presented here may lead to a better understanding of how the DWH spill impacted shipwreck materials and other marine metal infrastructure

    A preliminary bibliographic survey of the insects found in poultry houses from the Neotropical Region, with remarks on selected taxa shared with native birds' nests

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    Species of insects associated to the habitat of Gallus gallus (Aves: Phasianidae) in the Neotropical Region belong to 144 identified species (42 Coleoptera; 14 Diptera; 17 Hymenoptera; 9 Siphonaptera; 1 Lepidoptera; 56 Hemiptera (one hybrid); 5 Dermaptera); 33 identified to genus (21 Coleoptera; 3 Diptera; 7 Hymenoptera; 1 Hemiptera; 1 Blattaria); 37 identified to family (23 Coleoptera; 9 Diptera; 2 Hymenoptera; 1 Lepidoptera; 2 Hemiptera); and 6 to order (2 Coleoptera; 1 Hymenoptera; 1 Siphonaptera; 1 Psocoptera; 1 Dermaptera). Most of the insects are haematophagous ectoparasites (Hemiptera; Siphonaptera; Diptera), detritivores (Coleoptera; Lepidoptera; Diptera; Blattaria), predators (Coleoptera; Diptera; Hemiptera; Dermaptera; Hymenoptera), and parasitoids (Hymenoptera). A total of 46 native American species and/or subspecies of Triatominae (Hemiptera: Reduviidae) were found in chicken houses, from which 18 were also found in birds’ nests. It was recently observed that other insects from poultry houses, generally exotic species, had colonized native American birds’ nests. Comments and remarks of selected taxa also found in birds’ nests from Argentina and other countries are provided.Fil: Di Iorio, Osvaldo Rubén. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Turienzo, Paola Noemí. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Exposure to Crude Oil and Chemical Dispersant May Impact Marine Microbial Biofilm Composition and Steel Corrosion

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    The release of hydrocarbons and chemical dispersant in marine environments may disrupt benthic ecosystems, including artificial reefs, formed by historic steel shipwrecks, and their associated organisms. Experiments were performed to determine the impacts of crude oil, dispersed crude oil, and dispersant on the community structure and function of microorganisms in seawater (SW) and biofilms formed on carbon steel, a common ship hull construction material. Steel corrosion was also monitored to illustrate how oil spills may impact preservation of steel shipwrecks. Microcosms were filled with seawater (SW) and incubated at 4°C. Carbon steel disks (CSDs) were placed in each tank, and tanks were amended with crude oil and/or dispersant or no treatment. SW and CSD biofilms were sampled biweekly for genetic analysis using Illumina sequencing of 16S ribosomal RNA gene amplicons. Predicted and sequenced bacterial metagenomes were analyzed to examine impacts of oil and dispersant on metabolic function. Gammaproteobacteria, Alphaproteobacteria, and Flavobacteriia dominated SW and biofilms. Bacterial community structure differed significantly between treatments for SW and biofilms. OTUs affiliated with known (Pseudomonas) and potential (Marinomonas) hydrocarbon-degraders were roughly twice as abundant in biofilms treated with oil and dispersed oil, and steel corrosion of CSDs in these treatments was higher compared to control and dispersant treatments. OTUs affiliated with the Rhodobacteraceae family (biofilm formers and potential oil degraders) were less abundant in the dispersant treatment compared to other treatments in biofilm and SW samples, but OTUs affiliated with the Pseudoalteromonas genus (biofilm formers and proposed hydrocarbon degraders) were more abundant in dispersant-treated biofilms. Overall, functional gene analyses revealed a decrease in genes (predicted using PICRUSt and observed in sequenced metagenomes) associated with hydrocarbon degradation in dispersant-treated biofilms. This study indicates that exposure to oil and dispersant could disrupt the composition and metabolic function of biofilms colonizing metal hulls, as well as corrosion processes, potentially compromising shipwrecks as ecological and historical resources

    Prestige drives epistemic inequality in the diffusion of scientific ideas

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    The spread of ideas in the scientific community is often viewed as a competition, in which good ideas spread further because of greater intrinsic fitness, and publication venue and citation counts correlate with importance and impact. However, relatively little is known about how structural factors influence the spread of ideas, and specifically how where an idea originates might influence how it spreads. Here, we investigate the role of faculty hiring networks, which embody the set of researcher transitions from doctoral to faculty institutions, in shaping the spread of ideas in computer science, and the importance of where in the network an idea originates. We consider comprehensive data on the hiring events of 5032 faculty at all 205 Ph.D.-granting departments of computer science in the U.S. and Canada, and on the timing and titles of 200,476 associated publications. Analyzing five popular research topics, we show empirically that faculty hiring can and does facilitate the spread of ideas in science. Having established such a mechanism, we then analyze its potential consequences using epidemic models to simulate the generic spread of research ideas and quantify the impact of where an idea originates on its longterm diffusion across the network. We find that research from prestigious institutions spreads more quickly and completely than work of similar quality originating from less prestigious institutions. Our analyses establish the theoretical trade-offs between university prestige and the quality of ideas necessary for efficient circulation. Our results establish faculty hiring as an underlying mechanism that drives the persistent epistemic advantage observed for elite institutions, and provide a theoretical lower bound for the impact of structural inequality in shaping the spread of ideas in science.Comment: 10 pages, 8 figures, 1 tabl

    ESSAYS ON AGRICULTURAL MARKET AND POLICIES: IMPORTED SHRIMP, ORGANIC COFFEE, AND CIGARETTES IN THE UNITED STATES

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    This dissertation focuses on topics in areas of agricultural and food policy, international trade, agricultural markets and marketing. The dissertation is structured as three papers. The first paper, Chapter 1, evaluates the impact of agricultural trade policies. Imported shrimp, which comprises nearly ninety percent of all United States shrimp consumption, have become the subject of antidumping and countervailing duty investigations in the past decade. I estimate the import demand for shrimp in the United States from 1999-2014, using the Barten’s synthetic model. I test the hypothesis of possible structural breaks in the import demand introduced by various trade policies: antidumping/countervailing duty investigations and impositions, and import refusals due to safety and environmental issues. Results show that these import-restricting policies have significant effects on the import shrimp demand, indicating that the omission of them would lead to biased estimates. Chapter 2, the second paper, examines how the burden of state cigarette tax is divided between producers/retailers and consumers, by using the Nielsen store-level scanner data on cigarette prices from convenience stores over the period 2011–2012. Cigarette taxes were found more than fully passed through to retail prices on average, suggesting consumers pay excess burden and market power exists in the cigarette industry. Utilizing information on the attributes of cigarette products, we demonstrated that tax incidence varied by brand and package size: pass-through rates for premium brands and carton-packaged cigarettes are higher than those for discount brands and cigarettes in packs, respectively, indicating possibilities of different demand elasticities across product tiers. Chapter 3, the third paper, focuses on identifying the demographic characteristics of households buying organic coffee, by examining the factors that influence the probability that a consumer will buy organic coffee, and which factors affect the amount organic coffee purchased. Using nationally representative household level data from 55,470 households over the period of 2011 to 2013 (Nielsen Homescan), and a censored demand model, we find that economic and demographic factors play a crucial role in the household choice of purchasing organic coffee. Furthermore, households are less sensitive to own-price changes in the case of organic coffee versus conventional coffee

    Contract and Grant Awards Fiscal Year 2006

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    I invite you to read this report Contract & Grant Awards, fiscal year 2006, which lists contract and grant (C&G) awards received by the University of New Mexico (UNM) during the period from July 1, 2005 - June 30, 2006 (FY06). These awards represent new funds that were acquired during FY06 by the main campus, branch campuses and education centers, and the Health Sciences Center (HSC). The HSC includes the School of Medicine, College of Nursing, and College of Pharmacy. The awards received for FY06 total 298.6M,ofwhich298.6M, of which 165.4M is attributed to the main campus and $133.2M to HSC. These awards assist in providing resources that are necessary to support and enhance the quality of research and teaching at UNM, as well as the opportunities for students to be trained in state-of-the-art laboratories in a variety of disciplines

    Mesopelagic Species and Their Poential Contribution to Food and Feed Security - A Case Study from Norway

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    The projected increase in global population will demand a major increase in global food production. There is a need for more biomass from the ocean as future food and feed, preferentially from lower trophic levels. In this study, we estimated the mesopelagic biomass in three Norwegian fjords. We analyzed the nutrient composition in six of the most abundant mesopelagic species and evaluated their potential contribution to food and feed security. The six species make up a large part of the mesopelagic biomass in deep Norwegian fjords. Several of the analyzed mesopelagic species, especially the fish species Benthosema glaciale and Maurolicus muelleri, were nutrient dense, containing a high level of vitamin A1, calcium, selenium, iodine, eicopentaenoic acid (EPA), docosahexaenoic acid (DHA) and cetoleic acid. We were able to show that mesopelagic species, whose genus or family are found to be widespread and numerous around the globe, are nutrient dense sources of micronutrients and marine-based ingredients and may contribute significantly to global food and feed security.publishedVersio

    Prevalence of anemia and deficiency of iron, folic acid, and zinc in children younger than 2 years of age who use the health services provided by the Mexican Social Security Institute

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    <p>Abstract</p> <p>Background</p> <p>In Mexico, as in other developing countries, micronutrient deficiencies are common in infants between 6 and 24 months of age and are an important public health problem. The objective of this study was to determine the prevalence of anemia and of iron, folic acid, and zinc deficiencies in Mexican children under 2 years of age who use the health care services provided by the Mexican Institute for Social Security (IMSS).</p> <p>Methods</p> <p>A nationwide survey was conducted with a representative sample of children younger than 2 years of age, beneficiaries, and users of health care services provided by IMSS through its regular regimen (located in urban populations) and its Oportunidades program (services offered in rural areas). A subsample of 4,955 clinically healthy children was studied to determine their micronutrient status. A venous blood sample was drawn to determine hemoglobin, serum ferritin, percent of transferrin saturation, zinc, and folic acid. Descriptive statistics include point estimates and 95% confidence intervals for the sample and projections for the larger population from which the sample was drawn.</p> <p>Results</p> <p>Twenty percent of children younger than 2 years of age had anemia, and 27.8% (rural) to 32.6% (urban) had iron deficiency; more than 50% of anemia was not associated with low ferritin concentrations. Iron stores were more depleted as age increased. Low serum zinc and folic acid deficiencies were 28% and 10%, respectively, in the urban areas, and 13% and 8%, respectively, in rural areas. The prevalence of simultaneous iron and zinc deficiencies was 9.2% and 2.7% in urban and rural areas. Children with anemia have higher percentages of folic acid deficiency than children with normal iron status.</p> <p>Conclusion</p> <p>Iron and zinc deficiencies constitute the principal micronutrient deficiencies in Mexican children younger than 2 years old who use the health care services provided by IMSS. Anemia not associated with low ferritin values was more prevalent than iron-deficiency anemia. The presence of micronutrient deficiencies at this early age calls for effective preventive public nutrition programs to address them.</p
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