Understanding culture and HIV/AIDS in sub-Saharan Africa

Early in the study of HIV/AIDS, culture was invoked to explain differences in the disease patterns between sub-Saharan Africa and Western countries. Unfortunately, in an attempt to explain the statistics, many of the presumed risk factors were impugned in the absence of evidence. Many cultural practices were stripped of their meanings, societal context and historical positioning and transformed into cofactors of disease. Other supposedly beneficial cultural traits were used to explain the absence of disease in certain populations, implicitly blaming victims in other groups. Despite years of study, assumptions about culture as a cofactor in the spread of HIV/AIDS have persisted, despite a lack of empirical evidence. In recent years, more and more ideas about cultural causality have been called into question, and often disproved by studies. Thus, in light of new evidence, a review of purported cultural causes of disease, enhanced by an understanding of the differences between individual and population risks, is both warranted and long overdue. The preponderance of evidence suggests that culture as a singular determinant in the African epidemic of HIV/AIDS falls flat when disabused of its biased and ethnocentric assumptions.Keywords: culture, HIV/AIDS, sub-Saharan Africa, population ris

Physiological Effects of Adding a Percentage of Body Weight During a 7 Week Stair Climbing Sprint Interval Training Program

The purpose of this study was to determine the effect of adding a percentage of bodyweight (BW) during a 7 week stair climbing (SC) sprint interval training (SIT) program on maximal oxygen consumption, body composition, and lower body peak power. Twenty-seven recreationally active males (22±2 yrs) were divided into 1 of 2 groups (non-weighted or weighted) and performed 4, 15 sec bouts of ‘all-out’ SC sprints separated by 90 secs of rest, 3x/week, for 7 weeks. Non-weighted stair climbers performed SC sprints without any additional load throughout the entire duration of the study, and weighted stair climbers performed SC sprints with a progressive load of 10% and 20% bodyweight (BW). After the first week of SC SIT, the weighted SC group increased to 10% BW for weeks 2-4, and 20% BW for weeks 5-7. Lower body peak power improvements were found after 4 and 7 weeks of SC SIT training, as well as maximal oxygen consumption improvements after 7 weeks of SC SIT for both non-weighted and weighted stair climbers with no significant differences between groups. These improvements in lower body peak power and maximal oxygen consumption are similar to previous SIT studies involving treadmills, cycle ergometers, and stair climbing. Also, the results indicate that the addition of a progressive load (10-20% BW) as in a weighted vest to SC SIT did not improve maximal oxygen consumption and lower body peak power when compared to non-weighted SC SIT since no additional physiological challenge (HR) was added with BW (10-20% BW) during SC SIT. Lastly, strength and conditioning coaches or personal trainers need to be cautious about adding a weighted vest to SC SIT since there is no added benefit in improving aerobic fitness or lower body peak power and may only increase the incidence of injury

Roll convection of binary fluid mixtures in porous media

We investigate theoretically the nonlinear state of ideal straight rolls in the Rayleigh-B\'enard system of a fluid layer heated from below with a porous medium using a Galerkin method. Applying the Oberbeck-Boussinesq approximation, binary mixtures with positive separation ratio are studied and compared to one-component fluids. Our results for the structural properties of roll convection resemble qualitatively the situation in the Rayleigh--B\'enard system without porous medium except for the fact that the streamlines of binary mixtures are deformed in the so-called Soret regime. The deformation of the streamlines is explained by means of the Darcy equation which is used to describe the transport of momentum. In addition to the properties of the rolls, their stability against arbitrary infinitesimal perturbations is investigated. We compute stability balloons for the pure fluid case as well as for a wide parameter range of Lewis numbers and separation ratios which are typical for binary gas and fluid mixtures. The stability regions of rolls are found to be restricted by a crossroll, a zigzag and a new type of oscillatory instability mechanism, which can be related to the crossroll mechanism

Key Components of Successful Sexuality Education for High Functioning Students with Autism Spectrum Disorder

To date, there is very little existing research on the sexuality education of high functioning adolescents with Autism Spectrum Disorder (ASD) even though current research suggests that 1 in 68 children are diagnosed with ASD (CDC, 2014). Through group consensus of experts in ASD representing families, school-based professionals, and researchers, this study aimed to reach an agreed upon understanding of the essential components necessary in teaching high functioning students with ASD about sexuality. Using the Delphi method, expert participants responded to three iterative questionnaires and provided their opinions and recommendations on the content, delivery, and responsibilities of schools and families regarding sexuality education curricula designed specifically for high functioning adolescents with ASD. Based on participant responses, the Guidelines for Developing Sexuality Education Curricula for High Functioning Adolescent Students with Autism Spectrum Disorder were developed. These guidelines are intended to be used as a tool to guide future sexuality education curriculum development that address the specific needs of high functioning students with ASD and to provide suggestions to modify existing curricula so that the needs of high functioning adolescents students are met. Additionally, families, school psychologists, and researchers are advised to utilize these Guidelines as an advocacy tool to increase awareness of the unique needs of high functioning students with ASD regarding their sexuality education and to initiate conversations and action

Analytical and numerical stability analysis of Soret-driven convection in a horizontal porous layer

We present an analytical and numerical stability analysis of Soret-driven convection in a porous cavity saturated by a binary fluid. Both the mechanical equilibrium solution and the monocellular flow obtained for particular ranges of the physical parameters of the problem are considered. The porous cavity, bounded by horizontal infinite or finite boundaries, is heated from below or from above. The two horizontal plates are maintained at different constant temperatures while no mass flux is imposed. The influence of the governing parameters and more particularly the role of the separation ratio, characterizing the Soret effect and the normalized porosity, are investigated theoretically and numerically. From the linear stability analysis, we find that the equilibrium solution loses its stability via a stationary bifurcation or a Hopf bifurcation depending on the separation ratio and the normalized porosity of the medium. The role of the porosity is important, when it decreases, the stability of the equilibrium solution is reinforced. For a cell heated from below, the equilibrium solution loses its stability via a stationary bifurcation when the separation ratio >0(Le,), while for 0, while a stationary or an oscillatory bifurcation occurs if mono the monocellular flow loses stability via a Hopf bifurcation. As the Rayleigh number increases, the resulting oscillatory solution evolves to a stationary multicellular flow. For a cell heated from above and <0, the monocellular flow remains linearly stable. We verified numerically that this problem admits other stable multicellular stationary solutions for this range of parameters

Priorización y planeamiento de proyectos de inspección de gasoductos, oleoductos y poliductos

La misión de PII es ser el líder en la industria de servicio de integridad de tuberías, creando valor para los clientes con soluciones innovadoras, servicios globales, tecnología, excelencia en ejecución y talento de primera clase. Por tanto, esta investigación permitirá poner en evidencia que la actual estrategia de priorización de proyectos no está alineada con la misión de la empresa, resultando en una visión cortoplacista donde los clientes cuyas líneas tienen bajo margen sufren un retraso en sus reportes, dañando la percepción de imagen que éstos tienen sobre General Electric

Krüppel-like factor 4 (KLF4) regulates the miR-183~96~182 cluster under physiologic and pathologic conditions

Cèl·lules mare embrionàries; Melanoma; MicroARNCélulas madre embrionarias; Melanoma; MicroARNEmbryonic stem cells; Melanoma; MicroRNAMicroRNAs (miRNAs) are a class of endogenous non-coding small RNAs that post-transcriptionally control the translation and stability of target mRNAs in a sequence-dependent manner. MiRNAs are essential for key cellular processes including proliferation, differentiation, cell death and metabolism, among others. Consequently, alterations of miRNA expression contribute to developmental defects and a myriad of diseases. The expression of miRNAs can be altered by several mechanisms including gene copy number alterations, aberrant DNA methylation, defects of the miRNA processing machinery or unscheduled expression of transcription factors. In this work, we sought to analyze the regulation of the miR-182 cluster, located at the 7q32 locus, which encodes three different miRNAs that are abundantly expressed in human embryonic stem cells and de-regulated in cancer. We have found that the Krüppel-like factor 4 (KLF4) directly regulates miR-182 cluster expression in human embryonic stem cells (hESCs) and in melanoma tumors, in which the miR-182 cluster is highly expressed and has a pro-metastatic role. Furthermore, higher KLF4 expression was found to be associated with metastatic progression and poor patient outcome. Loss of function experiments revealed that KLF4 is required for melanoma cell maintenance. These findings provide new insights into the regulation of the miR-182 cluster expression and new opportunities for therapeutic intervention in tumors in which the KLF4-miR-182 cluster axis is deregulated.This work was supported by NCI/NIH Grant (5R01CA155234), Instituto de Salud Carlos III (CP11/00052 and RD12/0036/0016) co-financed by the European Regional Development Fund (ERDF), and European Commission’s Framework Programme 7 through the Marie Curie Career Integration Grants

Naissance de la convection thermo-solutale en couche poreuse infinie avec effet Soret

Nous étudions la naissance de la convection dans une couche poreuse infinie, saturée par un fluide binaire, en présence d'effet Soret. Les parois horizontales, imperméables à la matière, sont maintenues à des températures constantes et différentes. Pour une cellule chauffée par le bas, la solution d'équilibre perd sa stabilité via une bifurcation stationnaire lorsque le facteur de séparation ψ est supérieur à ψ0, fonction du nombre de Lewis et de la porosité normalisée ; pour ψ0, alors qu'elle perd sa stabilité via une bifurcation stationnaire pour ψ0, while a stationary bifurcation occurs if ψ<0. These results are widely corroborated by direct numerical simulations. Keywords: convection thermosolutale; effet Soret; milieu poreux; stabilité linéaire; bifurcation; méthode spectrale; double-diffusive convection; Soret effect; porous media; linear stability; bifurcation; spectral metho