294 research outputs found

    Recent Advances in the Technology of Aluminium- Magnesium Alloys

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    ALLOYS of aluminium with copper. to which smallamounts of manganese. magnesium and silicon are added, belong to the well known group of alloys termed "'Duralumin ', and were amongst the earliest of aluminium alloys to be used commercially on account of their age-hardening characteristics. Alloys of aluminium with magnesium as the principal alloying element, first attracted the interest of investigators as early as 1900, and since then, cast alloys containing as much as 10% magnesium have been used for specified purpose

    A Note on the Spin of the 1970 KeV Level in Ba134

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    Sum-Peak-Coincidence Spectrometer and Gamma-Gamma Angular Correlation Studies in Cs<Sup>133</Sup>

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    Clinical Research Environment in India: Challenges and Proposed Solutions.

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    India has compelling need and keen aspirations for indigenous clinical research. Notwithstanding this need and previously reported growth the expected expansion of Indian clinical research has not materialized. We reviewed the scientific literature, lay press reports, and ClinicalTrials.gov data for information and commentary on projections, progress, and impediments associated with clinical trials in India. We also propose targeted solutions to identified challenges. The Indian clinical trial sector grew by (+) 20.3% CAGR (compound annual growth rate) between 2005 and 2010 and contracted by (-) 14.6% CAGR between 2010 and 2013. Phase-1 trials grew by (+) 43.5% CAGR from 2005-2013, phase-2 trials grew by (+) 19.8% CAGR from 2005-2009 and contracted by (-) 12.6% CAGR from 2009-2013, and phase-3 trials grew by (+) 13.0% CAGR from 2005-2010 and contracted by (-) 28.8% CAGR from 2010-2013. This was associated with a slowing of the regulatory approval process, increased media coverage and activist engagement, and accelerated development of regulatory guidelines and recuperative initiatives. We propose the following as potential targets for restorative interventions: Regulatory overhaul (leadership and enforcement of regulations, resolution of ambiguity in regulations, staffing, training, guidelines, and ethical principles [e.g., compensation]).Education and training of research professionals, clinicians, and regulators.Public awareness and empowerment. After a peak in 2009-2010, the clinical research sector in India appears to be experiencing a contraction. There are indications of challenges in regulatory enforcement of guidelines; training of clinical research professionals; and awareness, participation, partnership, and the general image amongst the non-professional media and public. Preventative and corrective principles and interventions are outlined with the goal of realizing the clinical research potential in India

    Methodology to map spatial variability of available nutrients in area of intensively growing potato (Solanum tuberosum) using remote sensing and GIS

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    A methodology is developed for mapping spatial variability of available nutrients of soils of a pocket growing potato (Solanum tuberosum L.) crop using GIS. For this purpose potato growing pockets of the Jalandhar district were demarcated based on the available information, ground truth and classification of the IRS P6 AWiFS image. The classified potato area in the image was taken as background to generate the sampling site map and representative soil samples of potato fields from these sites were collected along with geographical coordinates using GPS receiver(ETREX-VISTA, Garmin). Values of different parameters (like pH, OC, available P and K and micronutrients) were tagged with corresponding points and interpolation maps for each individual parameters were prepared using suitable semivariogram and kriging in remote sensing GIS software. These prepared maps were further classified giving suitable ranges of different soil parameters

    Integration of HIV Care into Community Management of Acute Childhood Malnutrition Permits Good Outcomes: Retrospective Analysis of Three Years of a Programme in Lusaka

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    Background While HIV has had a major impact on health care in southern Africa, there are few data on its impact on acute malnutrition in children in the community. We report an analysis of outcomes in a large programme of community management of acute malnutrition in the south of Lusaka. Programme activities and analysis Over 3 years, 68,707 assessments for undernutrition were conducted house-to-house, and children with severe acute malnutrition (SAM) or moderate acute malnutrition (MAM) were enrolled into either Outpatient Therapeutic Programme (OTP) or Supplementary Feeding Programme (SFP) respectively. Case records were analysed using tabulation and unconditional logistic regression. Findings 1,859 children (889 boys, 970 girls; median age 16 months) with MAM (n=664) or SAM (n=1,195) were identified. Of 1,796 children whose parents consented to testing, 185 (10.3%) were HIV positive. Altogether 1,163 (62.6%) were discharged as recovered from acute malnutrition. Case fatality while in the programme was 4.2% in children with SAM and 0.5% in those with MAM (RR of SAM 10.9; 95%CI 3.4,34.8; P<0.0001), and higher in children with HIV infection (RR 5.2, 95%CI 2.9, 9.0; P<0.0001). In multivariate analysis, HIV (OR 5.2; 95%CI 2.6, 10.1; P<0.0001), MUAC <11.5cm (OR 4.1; 95%CI 2.2, 7.4; P<0.0001) and the first year of the programme (OR 1.9; 95%CI 1.0, 3.4; P=0.04) all increased mortality. Children with HIV infection who were able to initiate antiretroviral therapy had lower mortality (RR 0.23; 95%CI 0.10, 0.57; P=0.0008). Interpretation Our programme suggests that a comprehensive community malnutrition programme, incorporating HIV care, can achieve low mortality even in a population heavily affected by HIV

    Improved general health of international adoptees, but immunization status still insufficient

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    We studied the demographic and clinical data from 495 adopted children seen between January 2002 and January 2007 to evaluate the medical condition and immunization status of international adoptees. The data of children from Chinese origin (53.5%) were compared to children arriving from other countries. Medical problems requiring treatment were present in 42.8% of the children. Parasitic gastrointestinal infection (22.0%) and skin abnormalities (22.4%) were diagnosed most often. Hepatitis B (1.2%) and tuberculosis (1%) were documented in some children; HIV, hepatitis C, and syphilis were not seen in any of the children. Antibody levels against diphtheria and tetanus were insufficient in about half of all children, particularly in those from China. In conclusion, most adoptive children had a good general health, with only a few having major medical problems. Many adoptive children had an inadequate immunization status

    Hexagonal boron nitride tunnel barriers grown on graphite by high temperature molecular beam epitaxy

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    We demonstrate direct epitaxial growth of high-quality hexagonal boron nitride (hBN) layers on graphite using high-temperature plasma-assisted molecular beam epitaxy. Atomic force microscopy reveals mono- and few-layer island growth, while conducting atomic force microscopy shows that the grown hBN has a resistance which increases exponentially with the number of layers, and has electrical properties comparable to exfoliated hBN. X-ray photoelectron spectroscopy, Raman microscopy and spectroscopic ellipsometry measurements on hBN confirm the formation of sp2-bonded hBN and a band gap of 5.9 ± 0.1 eV with no chemical intermixing with graphite. We also observe hexagonal moiré patterns with a period of 15 nm, consistent with the alignment of the hBN lattice and the graphite substrate

    In Situ Observations during Chemical Vapor Deposition of Hexagonal Boron Nitride on Polycrystalline Copper.

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    Using a combination of complementary in situ X-ray photoelectron spectroscopy and X-ray diffraction, we study the fundamental mechanisms underlying the chemical vapor deposition (CVD) of hexagonal boron nitride (h-BN) on polycrystalline Cu. The nucleation and growth of h-BN layers is found to occur isothermally, i.e., at constant elevated temperature, on the Cu surface during exposure to borazine. A Cu lattice expansion during borazine exposure and B precipitation from Cu upon cooling highlight that B is incorporated into the Cu bulk, i.e., that growth is not just surface-mediated. On this basis we suggest that B is taken up in the Cu catalyst while N is not (by relative amounts), indicating element-specific feeding mechanisms including the bulk of the catalyst. We further show that oxygen intercalation readily occurs under as-grown h-BN during ambient air exposure, as is common in further processing, and that this negatively affects the stability of h-BN on the catalyst. For extended air exposure Cu oxidation is observed, and upon re-heating in vacuum an oxygen-mediated disintegration of the h-BN film via volatile boron oxides occurs. Importantly, this disintegration is catalyst mediated, i.e., occurs at the catalyst/h-BN interface and depends on the level of oxygen fed to this interface. In turn, however, deliberate feeding of oxygen during h-BN deposition can positively affect control over film morphology. We discuss the implications of these observations in the context of corrosion protection and relate them to challenges in process integration and heterostructure CVD.P.R.K. acknowledges funding from the Cambridge Commonwealth Trust and the Lindemann Trust Fellowship. R.S.W. acknowledges a research fellowship from St. John’s College, Cambridge. S.H. acknowledges funding from ERC grant InsituNANO (no. 279342), EPSRC under grant GRAPHTED (project reference EP/K016636/1), Grant EP/H047565/1 and EU FP7 Work Programme under grant GRAFOL (project reference 285275). The European Synchrotron Radiation Facility (ESRF) is acknowledged for provision of synchrotron radiation and assistance in using beamline BM20/ROBL. We acknowledge Helmholtz-Zentrum-Berlin Electron storage ring BESSY II for synchrotron radiation at the ISISS beamline and continuous support of our experiments.This is the final version. It was first published by ACS at http://pubs.acs.org/doi/abs/10.1021/cm502603
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