484 research outputs found

    Intrauterine mix-up: chimerism and endocrinology

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    Statistical mechanics in the context of special relativity

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    In the present effort we show that SÎș=−kB∫d3p(n1+Îș−n1−Îș)/(2Îș)S_{\kappa}=-k_B \int d^3p (n^{1+\kappa}-n^{1-\kappa})/(2\kappa) is the unique existing entropy obtained by a continuous deformation of the Shannon-Boltzmann entropy S0=−kB∫d3pnln⁥nS_0=-k_B \int d^3p n \ln n and preserving unaltered its fundamental properties of concavity, additivity and extensivity. Subsequently, we explain the origin of the deformation mechanism introduced by Îș\kappa and show that this deformation emerges naturally within the Einstein special relativity. Furthermore, we extend the theory in order to treat statistical systems in a time dependent and relativistic context. Then, we show that it is possible to determine in a self consistent scheme within the special relativity the values of the free parameter Îș\kappa which results to depend on the light speed cc and reduces to zero as c→∞c \to \infty recovering in this way the ordinary statistical mechanics and thermodynamics. The novel statistical mechanics constructed starting from the above entropy, preserves unaltered the mathematical and epistemological structure of the ordinary statistical mechanics and is suitable to describe a very large class of experimentally observed phenomena in low and high energy physics and in natural, economic and social sciences. Finally, in order to test the correctness and predictability of the theory, as working example we consider the cosmic rays spectrum, which spans 13 decades in energy and 33 decades in flux, finding a high quality agreement between our predictions and observed data. PACS number(s): 05.20.-y, 51.10.+y, 03.30.+p, 02.20.-aComment: 17 pages (two columns), 5 figures, RevTeX4, minor typing correction

    Application opportunities of geographic information systems analysis to support achievement of the UNAIDS 90-90-90 targets in South Africa

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    In an effort to achieve control of the HIV epidemic, 90-90-90 targets have been proposed whereby 90% of the HIV-infected population should know their status, 90% of those diagnosed should be receiving antiretroviral therapy, and 90% of those on treatment should be virologically suppressed. In this article we present approaches for using relatively simple geographic information systems (GIS) analyses of routinely available data to support HIV programme management towards achieving the 90-90-90 targets, with a focus on South Africa (SA) and other high-prevalence settings in low- and middle-income countries. We present programme-level GIS applications to map aggregated health data and individual-level applications to track distinct patients. We illustrate these applications using data from City of Johannesburg Region D, demonstrating that GIS has great potential to guide HIV programme operations and assist in achieving the 90-90-90 targets in SA

    High seroprevalence of human herpesviruses in HIV-infected individuals attending primary healthcare facilities in rural South Africa

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    Seroprevalence data of human herpesviruses (HHVs) are limited for sub-Saharan Africa. These are important to provide an indication of potential burden of HHV-related disease, in particular in human immunodeficiency virus (HIV)-infected individuals who are known to be at increased risk of these conditions in the Western world. In this cross-sectional study among 405 HIV-infected and antiretroviral therapy naĂŻve individuals in rural South Africa the seroprevalence of HHVs was: herpes simplex virus type 1 (HSV-1) (98%), herpes simplex virus type 2 (HSV-2) (87%), varicella zoster virus (VZV) (89%), and 100% for both Epstein-Barr virus (EBV) and cytomegalovirus (CMV). Independent factors associated with VZV seropositivity were low educational status and having children. Lack of in-house access to drinking water was independently associated with positive HSV-1 serostatus, whereas Shangaan ethnicity was associated with HSV-2 seropositivity. Increasing age was associated with higher IgG titres to both EBV and CMV, whereas CD4 cell count was negatively associated with EBV and CMV IgG titres. Moreover, IgG titres of HSV-1 and 2, VZV and CMV, and CMV and EBV were positively correlated. The high HHV seroprevalence emphasises the importance of awareness of these viral infections in HIV-infected individuals in South Africa

    The church and paediatric HIV care in rural South Africa

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    Religion has substantial – positive and negative – influence on South Africa’s HIV context. This qualitative study explored possibilities for positive church engagement in paediatric HIV care in a rural district in Limpopo Province, South Africa. Opinions, attitudes and experiences of various stakeholders including religious leaders, healthcare workers and people infected/affected with/by HIV were investigated through participant observation, semi-structured interviews and focus group discussions. During the research the original focus on paediatric HIV care shifted to HIV care in general in reaction to participant responses. Participants identified three main barriers to positive church engagement in HIV care: (a) stigma and disclosure; (b) sexual associations with HIV and (c) religious beliefs and practices. All participant groups appreciated the opportunity and relevance of strengthening church involvement in HIV care. Opportunities for positive church engagement in HIV care that participants identified included: (a) comprehensive and holistic HIV care when churches and clinics collaborate; (b) the wide social reach of churches and (c) the safety and acceptance in churches. Findings indicate that despite barriers great potential exists for increased positive church engagement in HIV care in rural South Africa. Recommendations include increased medical knowledge and dialogue on HIV/AIDS within church settings, and increased collaboration between churches and the medical sector

    A 10-year cohort analysis of routine paediatric ART data in a rural South African setting

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    South Africa’s paediatric antiretroviral therapy (ART) programme is managed using a monitoring and evaluation tool known as TIER.Net. This electronic system has several advantages over paper-based systems, allowing profiling of the paediatric ART programme over time. We analysed anonymized TIER.Net data for HIV-infected children aged <15 years who had initiated ART in a rural district of South Africa between 2005 and 2014. We performed Kaplan–Meier survival analysis to assess outcomes over time. Records of 5461 children were available for analysis; 3593 (66%) children were retained in care. Losses from the programme were higher in children initiated on treatment in more recent years (P < 0·0001) and in children aged ≀1 year at treatment initiation (P < 0·0001). For children aged <3 years, abacavir was associated with a significantly higher rate of loss from the programme compared to stavudine (hazard ratio 1·9, P < 0·001). Viral load was suppressed in 48–52% of the cohort, with no significant change over the years (P = 0·398). Analysis of TIER.Net data over time provides enhanced insights into the performance of the paediatric ART programme and highlights interventions to improve programme performance.This study was funded by the US President’s Emergency Plan for AIDS Relief (PEPFAR) through the United States Agency for International Development (USAID) under Cooperative Agreement number 674-A-12-00015 to the Anova Health Institute.http://journals.cambridge.org/action/displayJournal?jid=HYGhb2016Microbiology and Plant Patholog

    Taxonomic status of the extinct Canary Islands Oystercatcher Haematopus meadewaldoi

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    Mitochondrial genes were sequenced from four specimens of the extinct Canary Islands Oystercatcher Haematopus meadewaldoi and compared with African Oystercatcher Haematopus moquini, Eurasian Oystercatcher Haematopus ostralegus and an old unidentified extralimital ‘black’ oystercatcher specimen from The Gambia. At these loci, H. meadewaldoi was approximately 99.65% identical to multiple Eurasian Oystercatcher samples and in phylogenetic trees fell within the range of genetic variation observed in that species. The mystery Gambian bird was resolved as an extralimital H. moquini. We conclude that H. meadewaldoi was most likely a recently diverged melanistic morph or subspecies of H.ostralegus, although further genomic studies will be required to determine whether there has been a period of isolation followed by introgression
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