624 research outputs found

    Effectiveness of highly active antiretroviral therapy in HIV-positive children: evaluation at 12 months in a routine program in Cambodia.

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    OBJECTIVE: Increasing access to highly active antiretroviral therapy to reach all those in need in developing countries (scale up) is slowly expanding to HIV-positive children, but documented experience remains limited. We aimed to describe the clinical, immunologic, and virologic outcomes of pediatric patients with >12 months of highly active antiretroviral therapy in 2 routine programs in Cambodia. METHODS: Between June 2003 and March 2005, 212 children who were younger than 13 years started highly active antiretroviral therapy. Most patients started a standard first-line regimen of lamivudine, stavudine, and nevirapine, using split adult fixed-dosage combinations. CD4 percentage and body weight were monitored routinely. A cross-sectional virologic analysis was conducted in January 2006; genotype resistance testing was performed for patients with a detectable viral load. RESULTS: Mean age of the subjects was 6 years. Median CD4 percentage at baseline was 6. Survival was 92% at 12 months and 91% at 24 months; 13 patients died, and 4 were lost to follow-up. A total of 81% of all patients had an undetectable viral load. Among the patients with a detectable viral load, most mutations were associated with resistance to lamivudine and non-nucleoside reverse-transcriptase inhibitor drugs. Five patients had developed extensive antiretroviral resistance. Being an orphan was found to be a predictor of virologic failure. CONCLUSIONS: This study provides additional evidence of the effectiveness of integrating HIV/AIDS care with highly active antiretroviral therapy for children in a routine setting, with good virologic suppression and immunologic recovery achieved by using split adult fixed-dosage combinations. Viral load monitoring and HIV genotyping are valuable tools for the clinical follow-up of the patients. Orphans should receive careful follow-up and extra support

    Raman Spectroscopy Study of Impacted DLC Coatings

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    Raman scattering is an excellent tool to characterize the structure of carbon atoms in diamond-like carbon (DLC). The study of DLC coatings in the sliding conditions has been conducted for a decade using Raman spectroscopy analysis. However, there is still insufficient information about how the structure of DLC coatings changes during repetitive impact. In this paper changes in the structure under 90o repetitive impact at a large number of cycles are presented

    The effect of maximum normal impact load, absorbed energy and contact impulse on the impact craters volume/depth of DLC coating under repetitive impacts

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    Recently, the requirements for measuring dynamic responses have become severe and varied in many industrial and research applications such as material testing, model analysis and crash testing1). Surface degradation often occurs due to this dynamic response. This phenomenon also appears in the DLC coatings material. In this present work, a self-developed horizontal impact tester can provides this type of response, which gives an effect to the impact craters volume/depth of DLC coating

    Vortex Loop Phase Transitions in Liquid Helium, Cosmic Strings, and High-T_c Superconductors

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    The distribution of thermally excited vortex loops near a superfluid phase transition is calculated from a renormalized theory. The number density of loops with a given perimeter is found to change from exponential decay with increasing perimeter to algebraic decay as T_c is approached, in agreement with recent simulations of both cosmic strings and high-T_c superconductors. Predictions of the value of the exponent of the algebraic decay at T_c and of critical behavior in the vortex density are confirmed by the simulations, giving strong support to the vortex-folding model proposed by Shenoy.Comment: Version to appear in Phys. Rev. Lett, with a number of corrections and addition

    Deformation and wear map of DLC coating under cyclic impacts

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    Generally, the construction of transition maps follow two different approaches ; empirical and physical modelling. However, only empirical approach is used in this study. In this century, there is no development of deformation-wear transition map of the DC coating under cyclic impact loading. Therefore, the aim of this study is to propose a new deformation-wear transition map of DLC coating based on variations of maximum normal impact loads and impact cycles for future design purposes

    Extreme Type-II Superconductors in a Magnetic Field: A Theory of Critical Fluctuations

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    A theory of critical fluctuations in extreme type-II superconductors subjected to a finite but weak external magnetic field is presented. It is shown that the standard Ginzburg-Landau representation of this problem can be recast, with help of a novel mapping, as a theory of a new "superconductor", in an effective magnetic field whose overall value is zero, consisting of the original uniform field and a set of neutralizing unit fluxes attached to NΦN_{\Phi} fluctuating vortex lines. The long distance behavior is related to the anisotropic gauge theory in which the original magnetic field plays the role of "charge". The consequences of this "gauge theory" scenario for the critical behavior in high temperature superconductors are explored in detail, with particular emphasis on questions of 3D XY vs. Landau level scaling, physical nature of the vortex "line liquid" and the true normal state, and fluctuation thermodynamics and transport. A "minimal" set of requirements for the theory of vortex-lattice melting in the critical region is also proposed and discussed.Comment: 28 RevTeX pages, 4 .ps figures; appendix A added, additional references, streamlined Secs. IV and V in response to referees' comment

    An Approach to Conceptual and Embodiment Design within a New Product Development Lifecycle Framework

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    [EN] The design of new innovative products is the result of an accurate and precise management of knowledge sources all over its life cycle, such as technology, market, competitors and suppliers. The work contributes with a framework that shows how the knowledge sources influence in the state-of-the-art and market needs so that they become opportunities for innovating products addressing the whole product life cycle. It provides a systematic path from the early generation of ideas to the production of a new product proposal. Through a deep analysis of previous research works of new product innovation life cycle development frameworks and linking it with knowledge management, strategic planning and scorecards, we came out with a structured contribution. The result considers the concurrent activities and its relationships all the way through the product life cycle that can help in creativity and innovation, combined with a process management proposal. Managing the sources of knowledge in highly dynamic markets and technologies is one of the major difficulties involved in innovative products design and development. The emerging knowledge from external sources is confronted with organisation internal knowledge and experience in order to achieve the first product correct.This work was supported by the Spanish Government and the Universitat Jaume I of Castellon (Spain) through research [project number P11B2009-37], entitled 'Methodologies for Implementing Product lifecycle management tools for mechanical Small and Medium Enterprises'.Vila, C.; Albinana, JC. (2016). An Approach to Conceptual and Embodiment Design within a New Product Development Lifecycle Framework. International Journal of Production Research. 54(10):2856-2874. https://doi.org/10.1080/00207543.2015.1110632S28562874541
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