1,384 research outputs found

    ReferralWeb--a resource location system guided by personal relations

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    Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 47-[48]).by Mehul A. ShahM.Eng

    Supercritical-fluid synthesis of FeF2 and CoF2 Li-ion conversion materials

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    The synthesis of the Li-ion conversion candidates, FeF2 and CoF2, obtained from the single source organometallic precursors [Fe(tta)3] (tta = C8H4F3O2S), and [Co(hfac)2[middle dot]2H2O] (hfac = C5H1F6O2), respectively, via a novel supercritical fluid (SCF) method is presented. The nature of the synthesis led to highly-crystalline FeF2 and CoF2 powders requiring no additional thermal treatment. The as-obtained powders were investigated for use as potential positive Li-ion conversion electrodes by means of chronopotentiometric measurements. The FeF2 cells displayed high initial capacities following electrochemical conversion (up to [similar]1100 mA h g-1 at a potential of 1.0 V vs. Li/Li+), with appreciable cyclic behaviour over 25 discharge-charge cycles. The deposition of a [similar]5 nm layer of amorphous carbon onto the surface of the active material following SCF treatment, likely facilitated adequate electron transport through an otherwise poorly conducting FeF2 phase. Similarly, CoF2 cells displayed high initial capacities (up to [similar]650 mA h g-1 at a potential of 1.2 V vs. Li/Li+), although significant capacity fading ensued in the subsequent cycles. Ex situ XRD measurements confirmed a poor reversibility in the conversion sequence for CoF2, with a complete loss of CoF2 crystallinity and the sole presence of a crystalline LiF phase following charging

    NEIGHBORHOOD-BASED APPROACH OF COLLABORATIVE FILTERING TECHNIQUES FOR BOOK RECOMMENDATION SYSTEM

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    Recommendation System or Recommender System help the user to predict the "rating" or "preference" a user would give to an item. Recommender systems in general helps the users to find content, products, or services (such as digital products, books, music, movie, TV programs, and web sites) by combining and analyzing suggestions from other users, which mean rating from various people, and users. These recommendation systems use analytic technology to calculate the results that a user is willing to purchase, and the users will receive recommendations to a product of their interest. The aim of the System is to provide a recommendation based on users likes or reviews or ratings. Recommendation system comprises of content based and collaborative based filtering techniques. In this paper, collaborative based filtering has been used to get the expected outcome. The expected outcome has been achieved through collaborative filtering with the help of correlation techniques which in turn comprises of Pearson correlation, cosine similarity, Kendall’ s Tau correlation, Jaccard similarity, Spearman Rank Correlation, Mean-squared distance, etc. This paper tells about which similarity metrics such us Pearson correlation (PC), constrained Pearson correlation (CPC), spearman rank correlation (SRC) which is good in the context of book recommendation system and then applied with neighborhood algorithm

    A review on activated carbon: process, application and prospects

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    Activated carbon (AC) is used in different states of applications after its discovery as a strong and reliable adsorbent. An overview on AC is presented together with revisiting the sources of AC generation; methods used to generate AC comprising of pyrolysis activation; physical activation; chemical activation and steam pyrolysis. The important factors affecting the AC production, the possible applications of AC and their future prospects are also discussed. AC is applied in water, wastewater and leachate treatments in many countries, especially to polish the color, remove the odor and some heavy metals. It is cheap and available, and can be produced from agricultural waste materials, e.g. rice husk, palm oil shell and coconut shell. The AC’s fine and porous structure and an extremely large particle surface area (>1000 m2/g) results in making it possessed powerful adsorptive properties. Therefore, the adsorption process using AC is found to be a potentially viable method of removing pollutants from aqueous solutions

    De Novo Assembly and Transcriptome Analysis of the Mediterranean Fruit Fly Ceratitis capitata Early Embryos

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    The agricultural pest Ceratitis capitata, also known as the Mediterranean fruit fly or Medfly, belongs to the Tephritidae family, which includes a large number of other damaging pest species. The Medfly has been the first non-drosophilid fly species which has been genetically transformed paving the way for designing genetic-based pest control strategies. Furthermore, it is an experimentally tractable model, in which transient and transgene-mediated RNAi have been successfully used. We applied Illumina sequencing to total RNA preparations of 8-10 hours old embryos of C. capitata, This developmental window corresponds to the blastoderm cellularization stage. In summary, we assembled 42,614 transcripts which cluster in 26,319 unique transcripts of which 11,045 correspond to protein coding genes; we identified several hundreds of long ncRNAs; we found an enrichment of transcripts encoding RNA binding proteins among the highly expressed transcripts, such as CcTRA-2, known to be necessary to establish and, most likely, to maintain female sex of C. capitata. Our study is the first de novo assembly performed for Ceratitis capitata based on Illumina NGS technology during embryogenesis and it adds novel data to the previously published C. capitata EST databases. We expect that it will be useful for a variety of applications such as gene cloning and phylogenetic analyses, as well as to advance genetic research and biotechnological applications in the Medfly and other related Tephritidae

    Pulmonary tuberculosis in HIV individuals: Preliminary report on clinical features and response to treatment

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    Objectives: To study the clinical, radiological and immunological profile of pulmonary tuberculosis in HIV infected patients and assess the response to short-course chemotherapy regimens. Methods: Seventy eight patients (68 males and 10 females) with HIV infection and having symptoms suggestive of tuberculosis attending the Government Hospital for Thoracic Medicine, Tambaram or the Tuberculosis Research Centre, Chennai were studied. The diagnosis of tuberculosis was based on clinical evaluation, bacteriological examination including sputum smear and culture and chest skiagram. HIV diagnosis was based on two tests (rapid/ELISA), detecting different antigens. CD4+ T cell counts were done on all patients initially and at the end of treatment. Blood tests and skiagrams were repeated at 2 months and at the end of treatment. All the patients were treated with standard (RNTCP) short course regimens. Patients were given all the doses under supervision during the initial intensive phase and through community DOTS providers in the continuation phase. Results: Sixty five patients had culture confirmed pulmonary tuberculosis, of whom 54 had smear positive disease, initially. The radiological manifestations were varied, with 11 subjects having miliary tuberculosis, 54 with non-homogeneous opacities and 10 with cavitation. The mean CD4 cell count at intake was 192 ± 172 cells/cumm. Patients showed good initial response to treatment with significant weight gain. At the end of 2 months of treatment, 91% of patients had sputum cultures negative for Mycobacterium tuberculosis. However, the CD4 % fell significantly by the sixth month. The study is being continued to assess the long-term response to SCC of patients with HIV and tuberculosis. Conclusions: Tuberculosis has a varied clinical presentation in patients with HIV infection. The spectrum of radiographic features ranges from normal to a miliary pattern. Inspite of clinical and bacteriological improvement during treatment, immunologic deterioration may continue

    REVIEW AND THEORETICAL STUDIES OF ETHANOL EXTRACT OF ABRUS PRECATORIUS AND CHARACTERISATION

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    The objectives of the present study are to analyze qualitative preliminary phytochemical screeningand antimicrobial properties of Abrus precatoriusL . The qualitative preliminary phytochemical performed in aqueous extracts and ethanolic extracts of Abrus precatoriusL were done and the bioactive compound was indentified with TLC plant extract shows three bands for the presence of phenolic compound and Rf values were 0.4,0.45,and 0.48.The UV-VIS shows the spectra at278 and 457 nm confirms the organic chromophores and fifty compounds were identified in the ethanolic extracts by GC-MS.The major components present in the Abrusprecatoriuswere αCyclooctanedione ,Furanone , 2,4-Dihydroxy-2,5-dimethyl-3(2H)-furan-3-one , 2-Oxopentanedioic acid ,PropenylFormate ,and various other compounds were identified as low level. These phytochemical are responsible for various pharmacological actions. The structure of the identification of ibuprofen sodium using Infra-red spectroscopy were carried various spectral studies. From these studies, i do know about the knowledge of chemistry and spectroscopy. The main objective of this study is to specified and unspecified impurities using high performance liquid chromatography, Assay method of Ibuprofen methods of characterization
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