105 research outputs found

    The impact and cost-effectiveness of combined HIV prevention scenarios among transgender women sex-workers in Lima, Peru: A mathematical modelling study

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    Background HIV incidence remains high among transgender women in Lima, Peru, most of whom report sex work. On the basis of a stakeholder analysis and health system capacity assessment, we designed a mathematical model to guide HIV programmatic planning among transgender women sex workers (TWSW) in Lima. Methods Using a deterministic compartmental model, we modelled HIV transmission among TWSW, their stable partners, and their clients to estimate the impact and cost-effectiveness of combinations of interventions compared with the standard of care on reducing HIV incidence over a 10-year period. We simulated HIV transmission accounting for differences in sexual positioning in anal intercourse and condom use by partner type and fitted the model to HIV surveillance data using Latin hypercube sampling. The interventions we considered were 15% relative increase in condom use with clients and 10% relative increase with stable partners; increase in antiretroviral treatment (ART) coverage at CD4 count lower than 500 cells per mm3 and greater than or equal to 500 cells per mm3; and 15% pre-exposure prophylaxis (PrEP) coverage using generic and branded formulations. We considered a basic scenario accounting for current limitations in the Peruvian HIV services and an enhanced scenario assuming achievement of the UNAIDS 90-90-90 targets and general improvements in HIV services. The 50 best fits according to log-likelihood were used to give the minimum and maximum values of intervention effect for each combination. We used disability-adjusted life-years (DALYs) to measure the negative health outcomes associated with HIV infection that could be averted through the interventions investigated and calculated incremental cost-effectiveness ratios to compare their cost-effectiveness. Findings Under the basic scenario, combining the four interventions of increasing condom use with clients and stable partners, extending ART to people with CD4 count greater than or equal to 500 cells per mm3, and 15% PrEP coverage with generic drugs would avert 47% (range 27–51) of new infections in TWSW, their clients, and their stable partners over 10 years, with an incremental cost-effectiveness ratio of US509perDALYaverted.Undertheenhancedscenario,thisstrategywouldavert61509 per DALY averted. Under the enhanced scenario, this strategy would avert 61% (44–64) of new infections among this population with an incremental cost-effectiveness ratio of 1003 per DALY averted. Under both scenarios, implementation of this strategy approaches or surpasses the 50% incidence reduction goal and would represent a cost-effective use of country resources if generic PrEP drugs are used. The total cost of implementing this strategy under the enhanced scenario would be approximately $1·2 million per year over 10 years, corresponding to 10% of the current Global Fund's yearly contribution in Peru. Interpretation Investments in HIV services among TWSW in Lima would be cost-effective, even under stringent cost-effectiveness criteria when accounting for setting-specific resource constraints. Notable improvements in HIV testing rates, innovative interventions to increase condom use, and reduced PrEP costs will be key to achieving the 50% incidence reduction goal. Modelling studies incorporating stakeholders' perspectives and health system assessments can bring added value to HIV policy making

    Mapeo de la vulnerabilidad a la degradación de pastizales mediante AHP-GIS & RPAS en la microcuenca Pomacochas - Perú

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    In Peru,rangeland monitoring is increasingly essential to support farmers and strengthen new public policies for sustainable management at the watershed level. In this research, we sought to map the vulnerability to grassland degradation in the Pomacochas micro-watershed, Amazonas -Peru. For this, criteria were used (NDVI, precipitation, SOM, soil texture, soil pH and slope). Also, based on expert consultation and the Analytical Hierarchy Process (AHP), the importance of the criteria was weighed. Then, the land suitability map was generated to assess rangeland vulnerability by weighted superimposition of the criteria maps. NDVI was the most important criterion, while land slope was the least important. AHP and GIS based modeling shows that about 4012.08 km2(62.98%) of the total study area is in the category "slightly vulnerable" (C3) to grassland degradation. The results were also validated by means of four validation plots using images from a Remotely Piloted Aircraft (RPA). The study will provide support for decision making in the management of grasslands in micro-watershedsEn Perú, realizar un monitoreo de pastizales es cada vez más esencial para apoyar a los productores agropecuarios y fortalecer nuevas políticas públicas enmarcadas a un manejo sostenible a nivel de cuencas hidrográficas. En esta investigación se buscó mapear la vulnerabilidad a la degradación de pastizales en la microcuenca de Pomacochas, Amazonas − Perú. Para ello, se utilizaron criterios (NDVI, precipitación, MOS, textura del suelo, pH y pendiente). También, basado en consulta a expertos y el Proceso de Jerarquía Analítica (AHP), se sopeso la importancia de los criterios. Luego, se generó el mapa de aptitud del territorio para evaluar la vulnerabilidad de pastizales mediante superposición ponderada de los mapas de criterios. NDVI fue el criterio más importante, mientras que, la pendiente del terreno fue el menos importante. El modelado basado en AHP y SIG muestra que alrededor de 4012.08 km2 (62.98%) del área total de estudio se encuentran en la categoría “ligeramente vulnerable” (C3) a la degradación de pastizales. Asimismo, se validó los resultados mediante cuatro parcelas de validación empleando imágenes de un Aeronave Piloteada Remotamente (RPA). El estudio brindará apoyo para la toma de decisiones en torno al manejo de los pastizales en microcuencas

    Addressing quality and usability of surface water bodies in semi-arid regions with mining influences

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    Water resources management has considerable importance, specifically in the context of climate change. This subject has introduced new challenges in semi-arid regions with water quality problems, such as the Iberian Pyrite Belt, which is one of the largest metallogenetic provinces in the world and one of the driest regions in Europe. Positioned in the Mediterranean context, the region has a high density of polymetallic sulphide mines that promote the degradation of water systems. The present study aims to assess the water quality in the Pyrite Belt, considering a total of 34 surface water bodies, including constructed reservoirs, permanent and ephemeral streams, and mining facilities with accumulated water (e.g., pit lakes and mining dams). The water samples were analysed for physico-chemical properties, including field parameters (pH, electrical conductivity), alkalinity/acidity, hardness, anions, and potential toxic elements. The results were used for hydrochemical classifications and the assessment of suitability for public uses. Statistical methods, such as hierarchical cluster analysis and nearest centroid classifier, were used for grouping and evaluating the similarity between water bodies. Two groups were generated from the analysis: i) constructed lakes with alkaline and sodium signatures; and ii) waters suffering from the influence of mining wastes, e.g., showing high acidity, sulphate and metal contents. Therefore, the loss of water quality in the vicinity of mines reflects the impact of acid mine drainage. The methodological approach used may be applied to the integrated management of water resources in regions with mining influences and where it is necessary to combat drought and water scarcity scenarios.Patricia Gomes acknowledge FCT (Science and Technology Foundation, Portugal) by the research fellowship under the POCH (Programa Operacional Capital Humano) supported by the European Social Fund and National Funds of MCTES (Ministerio da Ciencia, Tecnologia e Ensino Superior) with reference SFRH/BD/108887/2015. This work was co-funded by the European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Internacionalizacao) - project ICT (UID/GEO/04683/2013) with reference POCI-01-0145-FEDER-007690 and project Nano-MINENV number 029259

    Análises melissopalinológicas, físico-químicas, atividade antirradicalar e perfil químico por UPLC-DAD-QTOF-MS/MS dos méis de Frieseomelitta doederleini (Abelha Branca): comparação com os fenólicos presentes nas flores de Mimosa tenuiflora (Jurema Preta).

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    Este trabalho está inserido no projeto MeliApis: Projeto de inserção e capacitação da mulher em atividade da agricultura familiar em municípios do território do sertão próximo ao Rio São Francisco, sendo a continuação dos estudos com os produtos apícolas e meliponí- colas.7-13 Neste estudo, com as amostras dos méis de abelha branca foram realizadas análises físico-químicas, químicas por Cromatografia a Líquido de Ultra-eficiência acoplada com detectores de Arranjo de Diodo e Espectrômetro de Massas tipo triploquadrupolo e Tempo de Vôo (UPLC-DAD-qTOF-MS/MS), teor de minerais e atividade antirradicalar, como também foi realizada a análise e comparação do perfil químico das flores de Mimosa tenuiflora (jurema preta), principal espécie vegetal que apresentou o tipo polínico predominante nos méis de abelha branca

    Stellar Astrophysics and Exoplanet Science with the Maunakea Spectroscopic Explorer (MSE)

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    The Maunakea Spectroscopic Explorer (MSE) is a planned 11.25-m aperture facility with a 1.5 square degree field of view that will be fully dedicated to multi-object spectroscopy. A rebirth of the 3.6m Canada-France-Hawaii Telescope on Maunakea, MSE will use 4332 fibers operating at three different resolving powers (R ~ 2500, 6000, 40000) across a wavelength range of 0.36-1.8mum, with dynamical fiber positioning that allows fibers to match the exposure times of individual objects. MSE will enable spectroscopic surveys with unprecedented scale and sensitivity by collecting millions of spectra per year down to limiting magnitudes of g ~ 20-24 mag, with a nominal velocity precision of ~100 m/s in high-resolution mode. This white paper describes science cases for stellar astrophysics and exoplanet science using MSE, including the discovery and atmospheric characterization of exoplanets and substellar objects, stellar physics with star clusters, asteroseismology of solar-like oscillators and opacity-driven pulsators, studies of stellar rotation, activity, and multiplicity, as well as the chemical characterization of AGB and extremely metal-poor stars.Comment: 31 pages, 11 figures; To appear as a chapter for the Detailed Science Case of the Maunakea Spectroscopic Explore

    Contributing factors for self-reported HIV in male Peruvian inmates: results of the 2016 prison census

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    IntroductionWorldwide, prisons are high-risk settings for the transmission of infectious diseases such as HIV. There is a need to understand the health conditions of prisoners to improve and implement timely strategies for HIV diagnosis and control. Hence, we aimed to identify factors associated with self-reported HIV (srHIV) among Peruvian inmates.MethodsThis study is a secondary data analysis of the First Peruvian Prison Census conducted in 2016. We estimated the prevalence of srHIV in prisoners who were male at birth and the association of srHIV with other social conditions, criminal records, and prevalent health conditions. Nested models identified a multivariable parsimonious model for factors associated with srHIV and yielding prevalence ratios adjusted by the included parameters.ResultsThe census surveyed 71,087 male inmates of whom 0.4% reported srHIV (n = 305), and 82% of whom were receiving antiretroviral treatment (n = 220). In our final multivariable model, srHIV was independently associated with age between 36 and 55 years old vs. >55 years old [parsimonious prevalence ratio (pPR) = 1.98, 95% CI, 0.96–4.08], having a stable partner out of prison (pPR = 1.64, 95% CI, 1.24–2.19), being homosexual (pPR = 4.16, 95% CI, 2.50–6.90), self-report of prevalent tuberculosis co-infection (pPR = 2.55, 95% CI, 1.82–3.58), self-report of prevalent sexually transmitted infections (pPR = 34.49, 95% CI, 24.94–47.70), and self-report of prevalent illicit drug use 30 days before the survey (pPR = 1.91, 95% CI, 1.43–2.56).ConclusionSelf-reported HIV is associated with multiple social, health and prison risks among Peruvian inmates. Deeply understanding these factors would help to design HIV prevention and control strategies in Peruvian prisons

    Age and date for early arrival of the Acheulian in Europe (Barranc de la Boella, la Canonja, Spain)

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    The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ,1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place.The research at Barranc de la Boella has been carried out with the financial support of the Spanish Ministerio de Economı´a y Competitividad (CGL2012- 36682; CGL2012-38358, CGL2012-38434-C03-03 and CGL2010-15326; MICINN project HAR2009-7223/HIST), Generalitat de Catalunya, AGAUR agence (projects 2014SGR-901; 2014SGR-899; 2009SGR-324, 2009PBR-0033 and 2009SGR-188) and Junta de Castilla y Leo´n BU1004A09. Financial support for Barranc de la Boella field work and archaeological excavations is provided by the Ajuntament de la Canonja and Departament de Cultura (Servei d’Arqueologia i Paleontologia) de la Generalitat de Catalunya. A. Carrancho’s research was funded by the International Excellence Programme, Reinforcement subprogramme of the Spanish Ministry of Education. I. Lozano-Ferna´ndez acknowledges the pre-doctoral grant from the Fundacio´n Atapuerca. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Expression of P. falciparum var Genes Involves Exchange of the Histone Variant H2A.Z at the Promoter

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    Plasmodium falciparum employs antigenic variation to evade the human immune response by switching the expression of different variant surface antigens encoded by the var gene family. Epigenetic mechanisms including histone modifications and sub-nuclear compartmentalization contribute to transcriptional regulation in the malaria parasite, in particular to control antigenic variation. Another mechanism of epigenetic control is the exchange of canonical histones with alternative variants to generate functionally specialized chromatin domains. Here we demonstrate that the alternative histone PfH2A.Z is associated with the epigenetic regulation of var genes. In many eukaryotic organisms the histone variant H2A.Z mediates an open chromatin structure at promoters and facilitates diverse levels of regulation, including transcriptional activation. Throughout the asexual, intraerythrocytic lifecycle of P. falciparum we found that the P. falciparum ortholog of H2A.Z (PfH2A.Z) colocalizes with histone modifications that are characteristic of transcriptionally-permissive euchromatin, but not with markers of heterochromatin. Consistent with this finding, antibodies to PfH2A.Z co-precipitate the permissive modification H3K4me3. By chromatin-immunoprecipitation we show that PfH2A.Z is enriched in nucleosomes around the transcription start site (TSS) in both transcriptionally active and silent stage-specific genes. In var genes, however, PfH2A.Z is enriched at the TSS only during active transcription in ring stage parasites. Thus, in contrast to other genes, temporal var gene regulation involves histone variant exchange at promoter nucleosomes. Sir2 histone deacetylases are important for var gene silencing and their yeast ortholog antagonises H2A.Z function in subtelomeric yeast genes. In immature P. falciparum parasites lacking Sir2A or Sir2B high var transcription levels correlate with enrichment of PfH2A.Z at the TSS. As Sir2A knock out parasites mature the var genes are silenced, but PfH2A.Z remains enriched at the TSS of var genes; in contrast, PfH2A.Z is lost from the TSS of de-repressed var genes in mature Sir2B knock out parasites. This result indicates that PfH2A.Z occupancy at the active var promoter is antagonized by PfSir2A during the intraerythrocytic life cycle. We conclude that PfH2A.Z contributes to the nucleosome architecture at promoters and is regulated dynamically in active var genes
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