2,038 research outputs found

    Development and Application of a User-Friendly Decision Support Tool for Optimization of Wastewater Treatment Technologies in India

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    This is the author accepted manuscriptThe selection of suitable wastewater treatment solutions is a complex problem that requires the careful consideration of many factors. With water at a premium and water consumption increasing, India is facing a challenging time ahead, requiring effective water treatment solutions. The Wastewater Decision Support Optimiser (WiSDOM) presented here is a user-friendly software package designed to aid in the formulation and configuration of wastewater systems in developing countries such as India. WiSDOM employees advanced multi-objective optimisation and decision analysis techniques to identify optimal wastewater treatment options. It has been demonstrated that WiSDOM can adapt to a wide array of scenarios, considering a range of contributing factors (technical, environmental, economic and social), enabling an engineer to make more informed decisions

    Emerging pollutants in developing countries: Optimising sustainable treatment solutions

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    This is the author accepted manuscriptOver the past decade the research surrounding the occurrence, source, fate and removal of emerging pollutants has been increasing. The aim of this study was to create an add-on program which analyses the removal of emerging pollutants, to an existing decision support tool (WiSDOM). The tool was also used to evaluate the performance of each optimal solution in terms of removal of conventional pollutants using Multi Objective Genetic Algorithms and Multi Criteria Decision Analysis. Information was collated regarding minimum and maximum concentrations of emerging pollutants for surface water, groundwater, untreated wastewater, drinking water and treated wastewater. This information was used to populate an Excel Spreadsheet Program (ESP) which analysed the removal efficiencies of 13 different emerging pollutants for 42 wastewater treatment unit processes. The ESP is incorporated into the WiSDOM tool to allow the tool to calculate the removal of emerging pollutants. Three main scenarios were created to test the application of the tool and ESP. Scenario 1 focussed on the removal of emerging pollutants from from areas effected by tourism at different scales. Scenario 2 looked at the treatment suited for the removal of emerging pollutants from different socio-economic regions. Lastly, Scenario 3 looked at removing emerging pollutants from hospital and industrial wastewater. The scenarios were focused on wastewater treatment in India and investigated the removal of 13 emerging pollutants commonly found in India.Engineering and Physical Sciences Research Council (EPSRC)European CommissionNatural Environment Research Council (NERC

    Optimising wastewater treatment solutions for the removal of contaminants of emerging concern (CECs): A case study for application in India

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    This is the author accepted manuscript. The final version is available from IWA Publishing via the DOI in this record.The aim of this study was to produce optimal wastewater treatment solutions to calculate the removal of different CECs found in developing countries. A new methodology was developed for a decision support tool (WiSDOM), which focuses on producing treatment solutions suited to treating water for reuse to Indian Water Quality Standards. WiSDOM-CEC analyses the removal of CECs through different treatment solutions and was also used to evaluate the performance of each treatment train solution in terms of removal of conventional pollutants using multi-objective optimisation and multi criteria decision analysis. Information was collected on different CECs across different regions of India, and the removal of eighteen different CECs through 42 wastewater treatment unit processes for five different regions of India was analysed. Comparisons between similar categories of CECs, such as non-steroidal anti-inflammatory showed that emerging contaminants all react differently to individual treatment options. For example, the removal of Ibuprofen (IBP) and Naproxen (NPX) varied from >80% and 0%, respectively, for a solution in Karnataka involving sedimentation, submerged aerated filter, ultra-filtration and Nano filtration. In Tamil Nadu results ranged from 36.8% to 72% for Diclofenac, 10.7% to 66.5% for IBP and 0% for NPX.European CommissionNatural Environment Research Council (NERC)Engineering and Physical Sciences Research Council (EPSRC

    User-Friendly Decision Support Tool for the Selection of Wastewater Treatment Technologies for the Removal of Emerging Contaminants

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    This is the author accepted manuscript.Natural Environment Research Council (NERC)Department of Science and Technology, Govt. of Indi

    Cyclic Tetrapyrrolic Photosensitisers from the leaves of Phaeanthus ophthalmicus

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    <p>Abstract</p> <p>Background</p> <p>Twenty-seven extracts from 26 plants were identified as photo-cytotoxic in the course of our bioassay guided screening program for photosensitisers from 128 extracts prepared from 64 terrestrial plants in two different collection sites in Malaysia - Royal Belum Forest Reserve in the State of Perak and Gunung Nuang in the State of Selangor. One of the photo-cytotoxic extracts from the leaves of <it>Phaeanthus ophtalmicus </it>was further investigated.</p> <p>Results</p> <p>The ethanolic extract of the leaves from <it>Phaeanthus ophtalmicus </it>was able to reduce the <it>in vitro </it>viability of leukaemic HL60 cells to < 50% when exposed to 9.6 J/cm<sup>2 </sup>of a broad spectrum light at a concentration of 20 μg/mL. Dereplication of the photo-cytotoxic fractions from <it>P. ophthalmicus </it>extracts based on TLC R<sub>f </sub>values and HPLC co-injection of reference tetrapyrrolic compounds enabled quick identification of known photosensitisers, pheophorbide-<it>a</it>, pheophorbide-<it>a </it>methyl ester, 13<sup>2</sup>-hydroxypheophorbide-<it>a </it>methyl ester, pheophytin-<it>a </it>and 15<sup>1</sup>-hydroxypurpurin 7-lactone dimethyl ester. In addition, compound <b>1 </b>which was not previously isolated as a natural product was also identified as 7-formyl-15<sup>1</sup>-hydroxypurpurin-7-lactone methyl ester using standard spectroscopic techniques.</p> <p>Conclusions</p> <p>Our results suggest that the main photosensitisers in plants are based on the cyclic tetrapyrrole structure and photosensitisers with other structures, if present, are present in very minor amounts or are not as active as those with the cyclic tetrapyrrole structure.</p

    Information resource preferences by general pediatricians in office settings: a qualitative study

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    BACKGROUND: Information needs and resource preferences of office-based general pediatricians have not been well characterized. METHODS: Data collected from a sample of twenty office-based urban/suburban general pediatricians consisted of: (a) a demographic survey about participants' practice and computer use, (b) semi-structured interviews on their use of different types of information resources and (c) semi-structured interviews on perceptions of information needs and resource preferences in response to clinical vignettes representing cases in Genetics and Infectious Diseases. Content analysis of interviews provided participants' perceived use of resources and their perceived questions and preferred resources in response to vignettes. RESULTS: Participants' average time in practice was 15.4 years (2–28 years). All had in-office online access. Participants identified specialist/generalist colleagues, general/specialty pediatric texts, drug formularies, federal government/professional organization Websites and medical portals (when available) as preferred information sources. They did not identify decision-making texts, evidence-based reviews, journal abstracts, medical librarians or consumer health information for routine office use. In response to clinical vignettes in Genetics and Infectious Diseases, participants identified Question Types about patient-specific (diagnosis, history and findings) and general medical (diagnostic, therapeutic and referral guidelines) information. They identified specialists and specialty textbooks, history and physical examination, colleagues and general pediatric textbooks, and federal and professional organizational Websites as information sources. Participants with access to portals identified them as information resources in lieu of texts. For Genetics vignettes, participants identified questions about prenatal history, disease etiology and treatment guidelines. For Genetics vignettes, they identified patient history, specialists, general pediatric texts, Web search engines and colleagues as information sources. For Infectious Diseases (ID) vignettes, participants identified questions about patients' clinical status at presentation and questions about disease classification, diagnosis/therapy/referral guidelines and sources of patient education. For ID vignettes, they identified history, laboratory results, colleagues, specialists and personal experience as information sources. CONCLUSION: Content analysis of office-based general pediatricians' responses to clinical vignettes provided a qualitative description of their perceptions of information needs and preferences for information resource for cases in Genetics and Infectious Diseases. This approach may provide complementary information for discovering practitioner's information needs and resource preferences in different contexts

    Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans

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    BACKGROUND: It is estimated that 60 million computed tomography (CT) scans were performed during 2006, with approximately 11% of those performed on children age 0–15 years. Various types of gonadal shielding have been evaluated for reducing exposure to the gonads. The purpose of this study was to quantify the radiation dose reduction to the gonads and its effect on image quality when a wrap-around male pediatric gonad shield was used during CT scanning. This information is obtained to assist the attending radiologist in the decision to utilize such male gonadal shields in pediatric imaging practice. METHODS: The dose reduction to the gonads was measured for both direct radiation and for indirect scattered radiation from the abdomen. A 6 cm(3 )ion chamber (Model 10X5-6, Radcal Corporation, Monrovia, CA) was placed on a Humanoid real bone pelvic phantom at a position of the male gonads. When exposure measurements with shielding were made, a 1 mm lead wrap-around gonadal shield was placed around the ion chamber sensitive volume. RESULTS: The use of the shields reduced scatter dose to the gonads by a factor of about 2 with no appreciable loss of image quality. The shields reduced the direct beam dose by a factor of about 35 at the expense of extremely poor CT image quality due to severe streak artifacts. CONCLUSION: Images in the direct exposure case are not useful due to these severe artifacts and the difficulties in positioning these shields on patients in the scatter exposure case may not be warranted by the small absolute reduction in scatter dose unless it is expected that the patient will be subjected to numerous future CT scans

    Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

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    The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

    Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

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    Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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