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A steady state laminar natural convection flow in a trapezoidal enclosure with discretely heated bottom wall, adiabatic top wall, and constant temperature cold inclined walls is performed. The finite volume based commercial code "ANSYS-FLUENT" is used to investigate the influence of discrete heating on natural convection flows in a trapezoidal cavity. The numerical solution of the problem covers various Rayleigh numbers ranging from 103 to 106, non-dimensional heating length ranging from 0.2 to 0.8 and Prandtl number is 0.7. The performance of the present numerical approach is represented in the form of streamfunction, temperature profile and Nusselt number. Heat transfer increases with increase of Rayleigh numbers at the corners of the cavity for same heating length from center of the bottom wall. However, the heat transfer rate is less and almost constant for the Rayleigh numbers considered. It is found that the average Nusselt number monotonically increases with increase of Rayleigh number and length of heat source. The variation of local and average Nusselt numbers is more significant for larger length of heating than smaller one. The heat transfer correlations useful for practical design problems have been predicted. [ABSTRACT FROM AUTHOR]

The title compound, C29H24N2OS, contains a phenothiazine moiety linked to a planar carbazole unit (r.m.s. deviation = 0.029 Å) by a C—C single bond. The phenothiazine moiety possesses a typical non-planar butterfly structure with a fold angle of 27.36 (9)° between the two benzene rings. The dihedral angle between the mean planes of the carbazole and phenothiazine units is 27.28 (5)°. In the crystal, molecules stack in pairs along the c-axis direction, linked by offset π–π interactions [intercentroid distance = 3.797 (1) Å]. There are C—H...π interactions present linking these dimers to form a three-dimensional structure.

The title compound, C21H17NO2, crystallizes with two independent molecules (A and B) in the asymmetric unit. The indoline ring system is almost planar in both molecules (r.m.s. deviations = 0.020 and 0.024 Å for molecules A and B, respectively). The benzyl and phenol rings are inclined to the indole ring system by 80.39 (12) and 68.39 (12)° in molecule A, and by 79.90 (13) and 74.88 (10)° in molecule B. The aryl rings are inclined to one another by 33.30 (14) and 30.62 (14)° in molecules A and B, respectively. In the crystal, A molecules are linked by pairs of O—H...O hydrogen bonds, forming inversion dimers. The same situation is observed for the B molecules and both sets of inversion dimers enclose R22(14) ring motifs. These dimers stack along the a-axis direction and are linked by offset π–π interactions [intercentroid distance = 3.6802 (13) Å] involving A and B indole ring systems, forming layers parallel to the ab plane.

Abstract The intercalation of captopril (CP) into the interlayers of montmorillonite (MMT) affords an intestine-selective drug delivery system that has a captopril-loading capacity of up to ca. 14 %w/w and which exhibits near-zero-order release kinetics.

Importance: In Africa, the persistently high HIV incidence rate among young women is the major obstacle to achieving the goal of epidemic control., Objective: To determine trends in coverage of HIV prevention and treatment programs and HIV incidence., Design, Setting, and Participants: This cohort study consisted of 2 sequential, community-based longitudinal studies performed in the Vulindlela and Greater Edendale area in KwaZulu-Natal, South Africa. Participants enrolled from June 11, 2014, to June 22, 2015 (2014 survey), with a single follow-up visit from June 24, 2016, to April 3, 2017 (2016 cohort), or enrolled from July 8, 2015, to June 7, 2016 (2015 survey), with a single follow-up visit from November 7, 2016, to August 30, 2017 (2017 cohort). Men and women aged 15 to 49 years were enrolled in the 2014 and 2015 surveys, and HIV-seronegative participants aged 15 to 35 years were followed up in the 2016 and 2017 cohorts. Analysis was conducted from January 1 through December 31, 2018., Exposures: HIV prevention and treatment programs in a real-world, nontrial setting., Main Outcomes and Measures: Trends in sex- and age-specific HIV incidence rates, condom use, voluntary medical male circumcision, knowledge of HIV-seropositive status, uptake of antiretroviral therapy, and viral suppression., Results: A total of 9812 participants (6265 women [63.9%]; median age, 27 years [interquartile range, 20-36 years]) from 11 289 households were enrolled in the 2014 survey, and 10 236 participants (6341 women [61.9%]; median age, 27 years [interquartile range, 20-36 years]) from 12 247 households were enrolled in the 2015 survey. Of these, 3536 of 4539 (annual retention rate of 86.7%) completed follow-up in the 2016 cohort, and 3907 of 5307 (annual retention rate of 81.4%) completed follow-up in the 2017 cohort. From 2014 to 2015, condom use with last sex partner decreased by 10% from 24.0% (n = 644 of 3547) to 21.6% (n = 728 of 3895; P = .12) in men and by 17% from 19.6% (n = 1039 of 6265) to 16.2% (n = 871 of 6341; P = .002) in women. Voluntary medical male circumcision increased by 13% from 31.9% (1102 of 3547) to 36.1% (n = 1472 of 3895); P = .007) in men, and the proportion of women reporting that their partner was circumcised increased by 35% from 35.7% (n = 1695 of 4766) to 48.2% (n = 2519 of 5207; P < .001). Knowledge of HIV-seropositive status increased by 21% from 51.8% (n = 504 of 3547) to 62.9% (n = 570 of 3895; P < .001) in men and by 14% from 64.6% (n = 1833 of 6265) to 73.4% (n = 2182 of 6341; P < .001) in women. Use of antiretroviral therapy increased by 32% from 36.7% (n = 341 of 3547) to 48.6% (n = 432 of 3895; P < .001) in men and by 29% from 45.6% (n = 1251 of 6265) to 58.8% (n = 1743 of 6341; P < .001) in women; HIV viral suppression increased by 20% from 41.9% (n = 401 of 3547) to 50.3% (n = 456 of 3895; P = .005) in men and by 13% from 54.8% (n = 1547 of 6265) to 61.9% (n = 1828 of 6341; P < .001) in women. Incidence of HIV declined in women aged 15 to 19 years from 4.63 (95% CI, 3.29-6.52) to 2.74 (95% CI, 1.84-4.09) per 100 person-years (P = .04) but declined marginally or remained unchanged among men and women in other age groups., Conclusions and Relevance: This study showed a significant decline in HIV incidence in young women; however, to further reduce HIV incidence, HIV prevention and treatment program coverage must be intensified and scaled up.

Background: Seasonal pseudohyperkalaemia has been described in colder northern hemisphere countries. The lower temperatures may inhibit red cell Na-K-ATPase allowing the efflux of potassium and higher measured levels. It has not been described in warmer subtropical climates., Aims: The aim was to determine if seasonal variation in serum potassium occurred in a temperate climate., Methods: We conducted a retrospective review of serum potassium results over two years in two South African provinces with different microclimates and seasonal temperatures. The study included patient samples from surrounding clinics and hospitals in Pretoria, Gauteng province, and in Durban, KwaZulu-Natal province, South Africa. Average temperature ranges were obtained from the South African weather service from the same period (June 2015-June 2017)., Results: A total of 91,420 results were analysed and we found a statistically significant difference between the January (summer) and June (winter) serum potassium levels (p < .0001). These results demonstrate that the winter months in South Africa are associated with significantly higher measured potassium results., Conclusion: Seasonal pseudohyperkalaemia may be more widespread than realized and can occur in more temperate climates and laboratories should take the appropriate action when transporting samples as this could influence interpretation and clinical management., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: In high HIV burden settings, maximising the coverage of prevention strategies is crucial to achieving epidemic control. However, little is known about the reach and effect of these strategies in some communities., Methods: We did a cross-sectional community survey in the adjacent Greater Edendale and Vulindlela areas in the uMgungundlovu district, KwaZulu-Natal, South Africa. Using a multistage cluster sampling method, we randomly selected enumeration areas, households, and individuals. One household member (aged 15-49 years) selected at random was invited for survey participation. After obtaining consent, questionnaires were administered to obtain sociodemographic, psychosocial, and behavioural information, and exposure to HIV prevention and treatment programmes. Clinical samples were collected for laboratory measurements. Statistical analyses were done accounting for multilevel sampling and weighted to represent the population. A multivariable logistic regression model assessed factors associated with HIV infection., Findings: Between June 11, 2014, and June 22, 2015, we enrolled 9812 individuals. The population-weighted HIV prevalence was 36·3% (95% CI 34·8-37·8, 3969 of 9812); 44·1% (42·3-45·9, 2955 of 6265) in women and 28·0% (25·9-30·1, 1014 of 3547) in men (p<0·0001). HIV prevalence in women aged 15-24 years was 22·3% (20·2-24·4, 567 of 2224) compared with 7·6% (6·0-9·3, 124 of 1472; p<0·0001) in men of the same age. Prevalence peaked at 66·4% (61·7-71·2, 517 of 760) in women aged 35-39 years and 59·6% (53·0-66·3, 183 of 320) in men aged 40-44 years. Consistent condom use in the last 12 months was 26·5% (24·1-28·8, 593 of 2356) in men and 22·7% (20·9-24·4, 994 of 4350) in women (p=0·0033); 35·7% (33·4-37·9, 1695 of 5447) of women's male partners and 31·9% (29·5-34·3, 1102 of 3547) of men were medically circumcised (p<0·0001), and 45·6% (42·9-48·2, 1251 of 2955) of women and 36·7% (32·3-41·2, 341 of 1014) of men reported antiretroviral therapy (ART) use (p=0·0003). HIV viral suppression was achieved in 54·8% (52·0-57·5, 1574 of 2955) of women and 41·9% (37·1-46·7, 401 of 1014) of men (p<0·0001), and 87·2% (84·6-89·8, 1086 of 1251) of women and 83·9% (78·5-89·3, 284 of 341; p=0·3670) of men on ART. Age, incomplete secondary schooling, being single, having more than one lifetime sex partner (women), sexually transmitted infections, and not being medically circumcised were associated with HIV-positive status., Interpretation: The HIV burden in specific age groups, the suboptimal differential coverage, and uptake of HIV prevention strategies justifies a location-based approach to surveillance with finer disaggregation by age and sex. Intensified and customised approaches to seek, identify, and link individuals to HIV services are crucial to achieving epidemic control in this community., Funding: The President's Emergency Plan for AIDS Relief through the Centers for Disease Control and Prevention., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objectives: Genital herpes simplex virus-2 (HSV-2) shedding in pregnant women in association with neonatal herpes infection has been widely studied but there is limited evidence of its association with pregnancy outcomes., Methods: In t his retrospective observational study, we included a subgroup of pregnant women who were enrolled in a randomized control behavioural intervention study that was conducted in South Africa in 2008-2010. In pregnancy, women had a HIV rapid test done and a genital swab taken to test for curable STIs and HSV-2 DNA. Subsequent visits were scheduled for 6, 10, 14 weeks and 9 months post-delivery. Pregnancy outcomes were documented at the 6-week or 10-week postpartum visit. Women were treated syndromically for curable STIs., Results: Among 615 women included in this data analysis, 36.6% (n=225) tested HIV positive and 8.3% (n=51) tested positive for genital HSV-2 shedding during pregnancy. Women <24 years and HIV-1 seropositive women were 1.5 and 2.5 times more likely to test positive for HSV-2 genital shedding respectively. STI treatment records were available for 158/205 (77.1%) women; all 87 women with symptomatic STIs were treated the same day, and 50/71 (70.4%) asymptomatic women received treatment at the subsequent visit. Remaining 21 (29.6%) asymptomatic women did not receive treatment because they failed to return for antenatal follow-up. In a multivariable regression analysis, genital HSV-2 shedding, HIV-1, Neisseria gonorrhoea , Chlamydia trachomatis and Trichomanas vaginalis were not associated with preterm deliveries, still births and low birth weight. However with stratification by treatment for a STI, asymptomatic women who were not treated were 3.3 times more likely to deliver prematurely (33.3%; n=6/18) when compared to women who were treated during pregnancy (13.2%; n=15/114) (p=0.042)., Conclusions: Genital HSV-2 shedding in pregnancy does not appear to alter pregnancy outcomes. Untreated curable STIs ( T.vaginalis, C.trachomatis, N.gonorrhoea ) were more likely associated with preterm births., Competing Interests: Competing interests: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background: The incidence of HIV infection in young women in Africa is very high. We did a large-scale community-wide phylogenetic study to examine the underlying HIV transmission dynamics and the source and consequences of high rates of HIV infection in young women in South Africa., Methods: We did a cross-sectional household survey of randomly selected individuals aged 15-49 years in two neighbouring subdistricts (one urban and one rural) with a high burden of HIV infection in KwaZulu-Natal, South Africa. Participants completed structured questionnaires that captured general demographic, socioeconomic, psychosocial, and behavioural data. Peripheral blood samples were obtained for HIV antibody testing. Samples with HIV RNA viral load greater than 1000 copies per mL were selected for genotyping. We constructed a phylogenetic tree to identify clusters of linked infections (defined as two or more sequences with bootstrap or posterior support ≥90% and genetic distance ≤4·5%)., Findings: From June 11, 2014, to June 22, 2015, we enrolled 9812 participants, 3969 of whom tested HIV positive. HIV prevalence (weighted) was 59·8% in 2835 women aged 25-40 years, 40·3% in 1548 men aged 25-40 years, 22·3% in 2224 women younger than 25 years, and 7·6% in 1472 men younger than 25 years. HIV genotyping was done in 1589 individuals with a viral load of more than 1000 copies per mL. In 90 transmission clusters, 123 women were linked to 103 men. Of 60 possible phylogenetically linked pairings with the 43 women younger than 25 years, 18 (30·0%) probable male partners were younger than 25 years, 37 (61·7%) were aged 25-40 years, and five (8·3%) were aged 41-49 years: mean age difference 8·7 years (95% CI 6·8-10·6; p<0·0001). For the 92 possible phylogenetically linked pairings with the 56 women aged 25-40 years, the age difference dropped to 1·1 years (95% CI -0·6 to 2·8; p=0·111). 16 (39·0%) of 41 probable male partners linked to women younger than 25 years were also linked to women aged 25-40 years. Of 79 men (mean age 31·5 years) linked to women younger than 40 years, 62 (78·5%) were unaware of their HIV-positive status, 76 (96·2%) were not on antiretroviral therapy, and 29 (36·7%) had viral loads of more than 50 000 copies per mL., Interpretation: Sexual partnering between young women and older men, who might have acquired HIV from women of similar age, is a key feature of the sexual networks driving transmission. Expansion of treatment and combination prevention strategies that include interventions to address age-disparate sexual partnering is crucial to reducing HIV incidence and enabling Africa to reach the goal of ending AIDS as a public health threat., Funding: President's Emergency Program for AIDS Relief, US Centers for Disease Control and Prevention, South African Medical Research Council, and MAC AIDS Fund., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In South Africa, various point-of-care hemoglobin meters are used. However, the regulatory framework for approval, implementation and oversight of use of point-of-care hemoglobin meters is suboptimal. We assessed the diagnostic accuracy of the HemoCue Hb 301, STAT-Site MHgb and URIT-12 point-of-care hemoglobin meters, compared to a central laboratory based reference assay, in a central laboratory and a community based clinic in Durban, South Africa. Differences in performance of the point-of-care assays, compared to the reference assay, were more pronounced in the community based clinic. Results were reasonable for the HemoCue Hb 301, but poor for the STAT-Site MHgb and the URIT-12. Poor test performance of point-of-care hemoglobin meters, and inadequate evaluations and oversight in South Africa, leads to suboptimal clinical care and clinical research, and increased costs. There is a need for proper evaluation and quality assurance of point-of-care tests, the results of which should be made widely available to key stakeholders.

Human immunodeficiency virus type 1 (HIV-1) genetic diversity poses a challenge to reliable viral load monitoring. Discrepancies between different testing platforms have been observed, especially for non-clade-B virus. Therefore we compare, in antiretroviral therapy (ART)-naïve South African subjects predominantly infected with HIV-1 clade-C, three commercially available assays: the COBAS AmpliPrep/COBAS TaqMan HIV-1 Test version 2.0 by Roche (CAP/CTM v2.0), the BioMérieux NucliSens Version 2.0 Easy Q/Easy Mag (NucliSens v2.0) and the Roche COBAS Amplicor HIV-1 Monitor Test Version 1.5 (Amplicor v1.5). Strong linear correlation was observed and Bland-Altman analyses showed overall good agreement between the assays with mean viral load differences of 0.078 log cp/ml (NucliSens v2.0 - Amplicor v1.5), 0.260 log cp/ml (CAP/CTM v2.0 - Amplicor v1.5) and 0.164 log cp/ml (CAP/CTM v2.0 - NucliSens v2.0), indicating lower mean viral load results for the Amplicor v1.5 and higher mean readings for the CAP/CTM v2.0. Consistent with observations following previous comparisons of CAP/CTM v2.0 versus Amplicor v1.5, the CAP/CTM v2.0 assay detected low-level viremia (median 65 cp/ml) in more than one-third of those in whom viremia had been undetectable (<20 cp/ml) in assays using the NucliSens platform. These levels of viremia are of uncertain clinical significance but may be of importance in early detection of ART resistance in those on treatment. Overall the three assays showed good comparability of results but with consistent, albeit relatively small, discrepancies for HIV-1 clade-C samples, especially in the low-viremic range that should be taken into account when interpreting viral load data.

Introduction: Lack of universal, annual testing for human immunodeficiency virus (HIV) in health facilities suggests that expansion of HIV testing and counselling (HTC) to non-clinical settings is critical to the achievement of national goals for prevention, care and treatment. Consideration should be given to the ability of lay counsellors to perform home-based HTC in community settings., Methods: We implemented a community cluster randomized controlled trial of home-based HTC in Sisonke District, South Africa. Trained lay counsellors conducted door-to-door HIV testing using the same rapid tests used by the local health department at the time of the study (SD Bioline and Sensa). To monitor testing quality and counsellor skill, additional dry blood spots were taken and sent for laboratory-based enzyme-linked immunosorbent assay (ELISA) testing. Sensitivity and specificity were calculated using the laboratory result as the gold standard., Results and Discussion: From 3986 samples, the counsellor and laboratory results matched in all but 23 cases. In 18 cases, the counsellor judged the result as indeterminate, whereas the laboratory judged 10 positive, eight negative and three indeterminate, indicating that the counsellor may have erred on the side of caution. Sensitivity was 98.0% (95% CI: 96.3-98.9%), and specificity 99.6% (95% CI: 99.4-99.7%), for the lay counsellor field-based rapid tests. Both measures are high, and the lower confidence bound for specificity meets the international standard for assessing HIV rapid tests., Conclusions: These findings indicate that adequately trained lay counsellors are capable of safely conducting high-quality rapid HIV tests and interpreting the results as per the kit guidelines. These findings are important given the likely expansion of community and home-based testing models and the shortage of clinically trained professional staff.