7 research outputs found

    Capture and Recycle of Industrial CO\u3csub\u3e2\u3c/sub\u3e Emissions Using Mircoalgae

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    A novel cyclic flow photobioreactor (PBR) for the capture and recycle of CO2 using microalgae was designed and deployed at a coal-fired power plant (Duke Energy’s East Bend Station). The PBR was operated continuously during the period May–September 2015, during which algae productivity of typically 0.1–0.2 g/(L day) was obtained. Maximum CO2 capture efficiency was achieved during peak sunlight hours, the largest recorded CO2 emission reduction corresponding to a value of 81 % (using a sparge time of 5 s/min). On average, CO2 capture efficiency during daylight hours was 44 %. The PBR at East Bend Station also served as a secondary scrubber for NOx and SOx, removing on average 41.5 % of the NOx and 100 % of the SOx from the flue gas. The effect of solar availability and self-shading on a rudimentary digital model of the cyclic flow PBR was examined using Autodesk Ecotect Analysis software. Initial results suggest that this is a promising tool for the optimization of PBR layout with respect to the utilization of available solar radiation

    Capture and Recycle of Industrial CO\u3csub\u3e2\u3c/sub\u3e Emissions Using Mircoalgae

    Get PDF
    A novel cyclic flow photobioreactor (PBR) for the capture and recycle of CO2 using microalgae was designed and deployed at a coal-fired power plant (Duke Energy’s East Bend Station). The PBR was operated continuously during the period May–September 2015, during which algae productivity of typically 0.1–0.2 g/(L day) was obtained. Maximum CO2 capture efficiency was achieved during peak sunlight hours, the largest recorded CO2 emission reduction corresponding to a value of 81 % (using a sparge time of 5 s/min). On average, CO2 capture efficiency during daylight hours was 44 %. The PBR at East Bend Station also served as a secondary scrubber for NOx and SOx, removing on average 41.5 % of the NOx and 100 % of the SOx from the flue gas. The effect of solar availability and self-shading on a rudimentary digital model of the cyclic flow PBR was examined using Autodesk Ecotect Analysis software. Initial results suggest that this is a promising tool for the optimization of PBR layout with respect to the utilization of available solar radiation

    Trends in Prevalence of Advanced HIV Disease at Antiretroviral Therapy Enrollment - 10 Countries, 2004-2015.

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    Monitoring prevalence of advanced human immunodeficiency virus (HIV) disease (i.e., CD4+ T-cell count <200 cells/ÎŒL) among persons starting antiretroviral therapy (ART) is important to understand ART program outcomes, inform HIV prevention strategy, and forecast need for adjunctive therapies.*,†,§ To assess trends in prevalence of advanced disease at ART initiation in 10 high-burden countries during 2004-2015, records of 694,138 ART enrollees aged ≄15 years from 797 ART facilities were analyzed. Availability of national electronic medical record systems allowed up-to-date evaluation of trends in Haiti (2004-2015), Mozambique (2004-2014), and Namibia (2004-2012), where prevalence of advanced disease at ART initiation declined from 75% to 34% (p<0.001), 73% to 37% (p<0.001), and 80% to 41% (p<0.001), respectively. Significant declines in prevalence of advanced disease during 2004-2011 were observed in Nigeria, Swaziland, Uganda, Vietnam, and Zimbabwe. The encouraging declines in prevalence of advanced disease at ART enrollment are likely due to scale-up of testing and treatment services and ART-eligibility guidelines encouraging earlier ART initiation. However, in 2015, approximately a third of new ART patients still initiated ART with advanced HIV disease. To reduce prevalence of advanced disease at ART initiation, adoption of World Health Organization (WHO)-recommended "treat-all" guidelines and strategies to facilitate earlier HIV testing and treatment are needed to reduce HIV-related mortality and HIV incidence

    Reconsidering the local after a transformative global experience : a comparison of two study abroad programs for preservice teachers

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    Denna jĂ€mförande studie analyserar tvĂ„ lĂ€rarstudenters erfarenheter av utlandsstudier - en fyra mĂ„nader lĂ„ng skolpraktik i Sverige och en treveckors interkulturell intensivkurs med skolobservationer i Frankrike. Trots att de skilde sig Ă„t gĂ€llande lĂ€ngd och struktur, syftade bĂ€gge programmen till att utveckla lĂ€rarstudenternas förstĂ„else av mĂ„ngfald och pedagogik ur ett globalt perspektiv. Genom anvĂ€ndning av bl.a. transformativ lĂ€randeteori (Mezirow, 1991) utgick studien frĂ„n följande frĂ„gor: (1) Vilka erfarenheter gĂ€llande lokal/global mĂ„ngfald och pedagogik gör lĂ€rarstudenter i tvĂ„ skilda program som inbegriper utlandsstudier? (2) Vilka programinslag bidrar till transformativt lĂ€rande? Resultaten betonar vikten av relevanta och interaktiva uppgifter, verkliga erfarenheter och stödjandet av personlig utveckling sĂ„ att studenter kan bli globalare i sitt tĂ€nkande.This comparative case study analyzes two study abroad experiences for preservice teachers—a 4-month student teaching placement in Sweden and a 3-week intensive intercultural course with school observations in France. Although they differed in duration and structure, both programs focused on developing preservice teachers’ understandings of diversity and pedagogy in a global context. Using transformative learning theory (Mezirow, 1991) research questions included (1) What are preservice teachers’ experiences in two different study abroad programs focused on local/global diversity and pedagogy? (2) According to participants, what programmatic elements contribute to transformative learning experiences in such programs? Results underscore the need for relevant and interactive assignments, hands-on experiences, and support for personal growth in programs that aim to help preservice teachers “go global.

    Formation of Lutein, ÎČ-Carotene and Astaxanthin in a <i>Coelastrella</i> sp. Isolate

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    In this study, the effect of media composition, N/P ratio and cultivation strategy on the formation of carotenoids in a Coelastrella sp. isolate was investigated. A two-stage process utilizing different media in the vegetative stage, with subsequent re-suspension in medium without nitrate, was employed to enhance the formation of carotenoids. The optimal growth and carotenoid content (ÎČ-carotene and lutein) in the vegetative phase were obtained by cultivation in M-8 and BG11 media. Use of a N/P ratio of 37.5 and low light intensity of 40 ÎŒmol m−2 s−1 (control conditions) led to optimal biomass production of up to 1.31 g L−1. Low concentrations of astaxanthin (maximum of 0.31 wt. %) were accumulated under stress conditions (nitrogen-deficient medium containing 1.5 % of NaCl and light intensity of 500 ÎŒmol m−2 s−1), while ÎČ-carotene and lutein (combined maximum of 2.12 wt. %) were produced under non-stress conditions. Lipid analysis revealed that palmitic (C16:0) and oleic (C18:1) constituted the main algal fatty acid chains (50.2 ± 2.1% of the total fatty acids), while esterifiable lipids constituted 17.2 ± 0.5% of the biomass by weight. These results suggest that Coelastrella sp. could also be a promising feedstock for biodiesel production

    Another history of museums: from the discourse to the museum-piece

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    The history of museums could get inspired on the procedures of material studies and of Anthropology in order to take a new stand and move away from the institutional approach and consider the approach of objects traditionally labelled as museum objects. The socalled “museum pieces” are supposed to have a number of characteristics, particularly some great historical and artistic qualities, sometimes an heritage quality, but above all the ability to make “friends” around the community or around the world. In all these respects, it is proposed here a number of research procedures that may supplement or enrich the directions usually assigned to the history of institutions
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