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CD32-RNA Co-localizes with HIV-RNA in CD3+ Cells Found within Gut Tissues from Viremic and ART-Suppressed Individuals.
BackgroundIdentifying biomarkers for cells harboring replication-competent HIV is a major research priority. Recently, there have been mixed reports addressing the possibility that CD32-expressing T cells are enriched for HIV. There is growing evidence that CD32 expression increases with cellular activation that may be related to, but not necessarily specific for, infection with HIV. However, the relationship of CD32 expression to HIV-infection in subtypes of tissue-resident leukocytes is unclear.MethodsFirst, we used duplex chromogenic in situ hybridization to identify cells actively transcribing RNA for both CD32 and HIV on human gut tissues. Then we performed multiplexed immunofluorescence and in situ hybridization (mIFISH) on sections from the same tissues to determine the phenotype of individual cells co-expressing HIV-RNA and CD32-RNA.ResultsHIV-RNA+ cells were more abundant in tissues from viremic individuals than in those receiving suppressive anti-retroviral therapy (ART). However, staining by both methods indicated that a higher proportion of HIV-RNA+ cells co-expressed CD32-RNA in ART-suppressed individuals than in those with viremia. The majority of HIV-RNA+ cells were CD3+.ConclusionsOur data suggest that the transcription of CD32-RNA is correlated with HIV transcriptional activity in CD3+ cells found within human gut tissue. Whether or not up-regulation of CD32-RNA is a direct result of HIV transcription or more global T-cell activation remains unclear
Dynamic Interactions among Boundaries and the Expansion of Sustainable Aquaculture
Aquaculture is the fastest growing food production system in the world, generating more than half of the global seafood harvested today. These type of activities are crucial to provide key nutritional components for humanity in the future as populations worldwide are increasing and the demands for securing food resources are imperative. Multiple socio-ecological factors such as weak regulations and focus on maximizing production limit production and threaten the sustainable growth of aquaculture. We present a novel policy framework to evaluate and pursue growth in aquaculture considering four boundaries: biological productivity, environmental constraints to that productivity, policy that inhibits or promotes different kinds of aquaculture, and social preferences that determine aquaculture markets. Using a range of scenarios, we have shown that sustainable growth in aquaculture requires simultaneous consideration of all four boundaries and the potential interactions between all of these options. Our proposed conceptual framework shows that to further expand the boundaries of aquaculture production, the policy focus must remain flexible to enable the adaptation of from single-boundary approaches. Our approach takes account of the current boundaries, helping to consider the adaptive policy, which is deemed as a necessary tool for considering the dynamic interactions among boundaries, thus addressing the problem of defining the evolving limits of sustainable aquaculture
Multiple linear regression analysis of factors affecting the consumption
Econometrics provides the researchers with methods, theoretical basements, and procedures that allow the formulation and estimation of economic models that explain the study variable during a reference time period, as well as making predictions about the behavior of the studied reality based on the explanatory variables. The entire process, analyzed from econometrics after having formulated and estimated the model, leads to a very important phase: the statistical validation, which helps the researcher to ensure that the model satisfactorily passes a series of tests. These tests will allow the use of the model not just to explain the behavior of the independent variable under study, but to make predictions based on scenarios of occurrence based on those explanatory variables included in the model, offering a theoretical-practical support to formulate policies related to the studied phenomenon. This research aims to generate the first elements to know the private consumption behavior in India in the period from 2012 to 201
U-Control Chart Based Differential Evolution Clustering for Determining the Number of Cluster in k-Means
The automatic clustering differential evolution (ACDE) is one of the clustering methods that are able to determine the cluster number automatically. However, ACDE still makes use of the manual strategy to determine k activation threshold thereby affecting its performance. In this study, the ACDE problem will be ameliorated using the u-control chart (UCC) then the cluster number generated from ACDE will be fed to k-means. The performance of the proposed method was tested using six public datasets from the UCI repository about academic efficiency (AE) and evaluated with Davies Bouldin Index (DBI) and Cosine Similarity (CS) measure. The results show that the proposed method yields excellent performance compared to prior researches
Academic performance in the high school mathematics standardized test at metropolitan and remote areas of Costa Rica schools in 2013
En este artículo se describe el rendimiento académico del estudiantado de la región metropolitana y zonas alejadas, en la prueba nacional de matemática correspondiente a la conclusión de la educación media, considerando la prueba específica, según la modalidad y tipo de colegio: diurno (diurno científico, diurno humanístico), nocturno, técnico o centros integrados para la educación de jóvenes y adultos (CINDEA). El objetivo principal es describir el rendimiento académico estudiantil en las pruebas nacionales de bachillerato de matemática, correspondientes al año 2013, según las regiones educativas. Para el análisis de dicha información se utilizó como fuente primaria el Informe Nacional de Bachillerato, emitido por el Ministerio de Educación Pública para las pruebas estandarizadas del 2013. Una de las conclusiones, a partir de este estudio, es la necesidad de llevar a cabo un análisis histórico del rendimiento de las instituciones educativas que han obtenido, en los últimos años, los promedios más altos y más bajos en las pruebas de bachillerato de matemática, para poder profundizar en las causas de dichos rendimientos.This article describes the academic performance of students from urban and distant areas in the national mathematics test corresponding to the completion of secondary education, considering the specific test and according to the different types of schools: daytime (daytime scientific, daytime humanistic), nighttime, technical or integrated centers for education of young people and adults (CINDEA, in its Spanish acronym). The main objective is to describe the students academic performance in the national mathematics test issued to complete high-school level, for the year 2013 and according to the country educational areas. For the analysis of such information, the main source used was the High-School Education National Report, issued by the Ministry of Public Education for 2013 standardized tests. One of the conclusions from this study is the need to carry out a historical analysis of the performance of educational institutions which have recently obtained the highest and lowest average grades in the high-school diploma tests, in order to be able to delve into the causes of those performances
Efficiently Manifesting Asynchronous Programming Errors in Android Apps
Android, the #1 mobile app framework, enforces the single-GUI-thread model,
in which a single UI thread manages GUI rendering and event dispatching. Due to
this model, it is vital to avoid blocking the UI thread for responsiveness. One
common practice is to offload long-running tasks into async threads. To achieve
this, Android provides various async programming constructs, and leaves
developers themselves to obey the rules implied by the model. However, as our
study reveals, more than 25% apps violate these rules and introduce
hard-to-detect, fail-stop errors, which we term as aysnc programming errors
(APEs). To this end, this paper introduces APEChecker, a technique to
automatically and efficiently manifest APEs. The key idea is to characterize
APEs as specific fault patterns, and synergistically combine static analysis
and dynamic UI exploration to detect and verify such errors. Among the 40
real-world Android apps, APEChecker unveils and processes 61 APEs, of which 51
are confirmed (83.6% hit rate). Specifically, APEChecker detects 3X more APEs
than the state-of-art testing tools (Monkey, Sapienz and Stoat), and reduces
testing time from half an hour to a few minutes. On a specific type of APEs,
APEChecker confirms 5X more errors than the data race detection tool,
EventRacer, with very few false alarms
Relación entre el engagement por uso de redes sociales y la práctica de ejercicio físico en los centros deportivos municipales de Barcelona
Introducción. El presente estudio analiza el uso de las redes sociales por parte de los centros deportivos municipales (CEM) de Barcelona y como esto puede relacionarse con la práctica de ejercicio físico. Metodología. Se calculó el engagement de los centros deportivos municipales de Barcelona mediante el registro de las interacciones en sus redes sociales (Facebook y Twitter), para luego determinar la relación existente entre el engagement y la práctica de ejercicio físico en Barcelona. Resultados. Los datos muestran que existe una relación positiva entre el engagement y la práctica de actividad física. Además, se identifica que los likes de Facebook determinaron la mayor relación. Discusión y conclusiones. A pesar de que la recogida de datos fue muy acotada (82 días), se recomienda que los centros deportivos gestionen la comunicación mediante redes sociales y presten atención en como involucrar a los usuarios
Increasing dominance of large lianas in Amazonian forests
Ecological orthodoxy suggests that old-growth forests should be close to dynamic equilibrium, but this view has been challenged by recent findings that neotropical forests are accumulating carbon and biomass, possibly in response to the increasing atmospheric concentrations of carbon dioxide. However, it is unclear whether the recent increase in tree biomass has been accompanied by a shift in community composition. Such changes could reduce or enhance the carbon storage potential of old-growth forests in the long term. Here we show that non-fragmented Amazon forests are experiencing a concerted increase in the density, basal area and mean size of woody climbing plants (lianas). Over the last two decades of the twentieth century the dominance of large lianas relative to trees has increased by 1.7–4.6% a year. Lianas enhance tree mortality and suppress tree growth, so their rapid increase implies that the tropical terrestrial carbon sink may shut down sooner than current models suggest. Predictions of future tropical carbon fluxes will need to account for the changing composition and dynamics of supposedly undisturbed forests
Student performance assessment using clustering techniques
The application of informatics in the university system management
allows managers to count with a great amount of data which, rationally treated,
can offer significant help for the student programming monitoring. This research
proposes the use of clustering techniques as a useful tool of management
strategy to evaluate the progression of the students’ behavior by dividing the
population into homogeneous groups according to their characteristics and
skills. These applications can help both the teacher and the student to improve
the quality of education. The selected method is the data grouping analysis by
means of fuzzy logic using the Fuzzy C-means algorithm to achieve a standard
indicator called Grade, through an expert system to enable segmentation.Universidad de la Costa, 2 Universidad Nacional Experimental Politécnica “Antonio José de Sucre”, Universidad Simón Bolívar, Corporación Universitaria Latinoamericana, Corporación Universitaria Minuto de Dios
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