Only Death Will Separate Us: The Role of Extramarital Partnerships among Himba Pastoralists.

Extramarital partnerships are highly stigmatized in many societies and are typically excluded from studies of family dynamics and social support. Nevertheless, in many societies such relationships are common and can have important impacts on resource security and health outcomes. However, current studies of these relationships come mainly from ethnographic studies, with quantitative data extremely rare. Here we present data from a 10-year study of romantic partnerships among a community of Himba pastoralists in Namibia, where concurrency is common. The majority of married men (97%) and women (78%) currently reported having more than one partner (n = 122). Using multilevel models comparing marital and nonmarital relationships, we found that, contrary to conventional wisdom surrounding concurrency, Himba form enduring bonds with extramarital partners that often last decades and are very similar to marital ones in terms of length, emotional affect, reliability, and future prospects. Qualitative interview data showed that extramarital relationships were imbued with a set of rights and obligations that, while distinct from those of spouses, provide an important source of support. Greater inclusion of these relationships in studies of marriage and family would provide a clearer picture of social support and resource transfers in these communities and help to explain variation in the practice and acceptance of concurrency around the world.

HIV Transmission Potential and Sex Partner Concurrency: Evidence for Racial Disparities in HIV Risk Among Gay and Bisexual Men (MSM).

We determined whether racial disparities in HIV infection among gay and bisexual men (MSM) may be partially explained by racial differences in the HIV transmission potential (i.e. mixing of people living with HIV and people not living with HIV or of unknown HIV serostatus) and density (i.e. sex partner concurrency) of sexual networks. Data included a behavioral survey, testing for HIV, and an egocentric sexual network survey. Mixed effects logistic regressions were used for hypothesis testing. Black (vs. non-Black) MSM were more likely to not know their partner's HIV serostatus (21.8% vs. 9.6%). Similar proportions reported sex partner concurrency (67.1% vs. 68.0%). In adjusted analyses, among Black MSM, sex partner concurrency significantly increased the odds of an HIV transmission potential partnership (TPP), and this association was not significant among non-Black indexes. The association between an HIV TPP and sex partner concurrency may help explain persistent racial disparities in HIV prevalence.

RESUMEN: Determinamos si las disparidades raciales en infecciones del VIH entre hombres homosexuales y bisexuales (hombres que tienen sexo con hombres) puede ser parcialmente explicado por diferencias raciales en el potencial de transmisión del VIH (es decir, mezcla de personas viviendo con VIH y personas que no viven con VIH o cuyo estado serológico del VIH es desconocido) y densidad (es decir, concurrencia de pareja sexual) de redes sexuales. Los datos incluyeron una encuesta de comportamiento, pruebas para el VIH y una encuesta de redes sexuales egocéntrica. Regresiones logísticas de efectos mixtos fueron usados para la prueba de hipótesis. HSH negros (vs. HSH no-negros) eran más propensos a no saber el estado serológico del VIH de su pareja (21.8% vs. 9.6%). Proporciones similares reportaron concurrencia de pareja sexual (67.1% vs. 68.0%). En análisis ajustados, entre HSH negros, la concurrencia de pareja sexual aumentó significativamente las probabilidades de una asociación potencial de transmisión del VIH (TPP por sus siglas en inglés), y esta asociación no fue significativa entre índices de no-negros. La asociación entre una TPP VIH y concurrencia de pareja sexual puede ayudar a explicar disparidades raciales persistentes en la prevalencia del VIH.

Sexual partner concurrency: is it a useful concept for HIV prevention? A systematic review of the evidence for intervention effectiveness in low- and middle-income countries.

If sexual partner concurrency drives HIV transmission dynamics, shouldn't HIV prevention efforts be addressing this behavior? We systematically reviewed studies evaluating interventions to reduce sexual partner concurrency in low- and middle-income countries using pre/post or multi-arm designs. Only two studies met our inclusion criteria; neither found significant differences by intervention exposure on self-reported concurrency. Overall, very few interventions have specifically targeted concurrency, and those that did have not been rigorously evaluated. In practice, concurrency may be difficult to separate from multiple partnerships more generally.

FCLQC: fast and concurrent lossless quality scores compressor.

BACKGROUND: Advances in sequencing technology have drastically reduced sequencing costs. As a result, the amount of sequencing data increases explosively. Since FASTQ files (standard sequencing data formats) are huge, there is a need for efficient compression of FASTQ files, especially quality scores. Several quality scores compression algorithms are recently proposed, mainly focused on lossy compression to boost the compression rate further. However, for clinical applications and archiving purposes, lossy compression cannot replace lossless compression. One of the main challenges for lossless compression is time complexity, where it takes thousands of seconds to compress a 1 GB file. Also, there are desired features for compression algorithms, such as random access. Therefore, there is a need for a fast lossless compressor with a reasonable compression rate and random access functionality. RESULTS: This paper proposes a Fast and Concurrent Lossless Quality scores Compressor (FCLQC) that supports random access and achieves a lower running time based on concurrent programming. Experimental results reveal that FCLQC is significantly faster than the baseline compressors on compression and decompression at the expense of compression ratio. Compared to LCQS (baseline quality score compression algorithm), FCLQC shows at least 31x compression speed improvement in all settings, where a performance degradation in compression ratio is up to 13.58% (8.26% on average). Compared to general-purpose compressors (such as 7-zip), FCLQC shows 3x faster compression speed while having better compression ratios, at least 2.08% (4.69% on average). Moreover, the speed of random access decompression also outperforms the others. The concurrency of FCLQC is implemented using Rust; the performance gain increases near-linearly with the number of threads. CONCLUSION: The superiority of compression and decompression speed makes FCLQC a practical lossless quality score compressor candidate for speed-sensitive applications of DNA sequencing data. FCLQC is available at https://github.com/Minhyeok01/FCLQC and is freely available for non-commercial usage.

Impact of concurrency on the performance of a whole exome sequencing pipeline.

BACKGROUND: Current high-throughput technologies-i.e. whole genome sequencing, RNA-Seq, ChIP-Seq, etc.-generate huge amounts of data and their usage gets more widespread with each passing year. Complex analysis pipelines involving several computationally-intensive steps have to be applied on an increasing number of samples. Workflow management systems allow parallelization and a more efficient usage of computational power. Nevertheless, this mostly happens by assigning the available cores to a single or few samples' pipeline at a time. We refer to this approach as naive parallel strategy (NPS). Here, we discuss an alternative approach, which we refer to as concurrent execution strategy (CES), which equally distributes the available processors across every sample's pipeline. RESULTS: Theoretically, we show that the CES results, under loose conditions, in a substantial speedup, with an ideal gain range spanning from 1 to the number of samples. Also, we observe that the CES yields even faster executions since parallelly computable tasks scale sub-linearly. Practically, we tested both strategies on a whole exome sequencing pipeline applied to three publicly available matched tumour-normal sample pairs of gastrointestinal stromal tumour. The CES achieved speedups in latency up to 2-2.4 compared to the NPS. CONCLUSIONS: Our results hint that if resources distribution is further tailored to fit specific situations, an even greater gain in performance of multiple samples pipelines execution could be achieved. For this to be feasible, a benchmarking of the tools included in the pipeline would be necessary. It is our opinion these benchmarks should be consistently performed by the tools' developers. Finally, these results suggest that concurrent strategies might also lead to energy and cost savings by making feasible the usage of low power machine clusters.

Real-Time Multiobject Tracking Based on Multiway Concurrency.

This paper explored a pragmatic approach to research the real-time performance of a multiway concurrent multiobject tracking (MOT) system. At present, most research has focused on the tracking of single-image sequences, but in practical applications, multiway video streams need to be processed in parallel by MOT systems. There have been few studies on the real-time performance of multiway concurrent MOT systems. In this paper, we proposed a new MOT framework to solve multiway concurrency scenario based on a tracking-by-detection (TBD) model. The new framework mainly focuses on concurrency and real-time based on limited computing and storage resources, while considering the algorithm performance. For the former, three aspects were studied: (1) Expanded width and depth of tracking-by-detection model. In terms of width, the MOT system can support the process of multiway video sequence at the same time; in terms of depth, image collectors and bounding box collectors were introduced to support batch processing. (2) Considering the real-time performance and multiway concurrency ability, we proposed one kind of real-time MOT algorithm based on directly driven detection. (3) Optimization of system level-we also utilized the inference optimization features of NVIDIA TensorRT to accelerate the deep neural network (DNN) in the tracking algorithm. To trade off the performance of the algorithm, a negative sample (false detection sample) filter was designed to ensure tracking accuracy. Meanwhile, the factors that affect the system real-time performance and concurrency were studied. The experiment results showed that our method has a good performance in processing multiple concurrent real-time video streams.

Characterizing Men Who Have Sex with Transgender Women in Lima, Peru: Sexual Behavior and Partnership Profiles.

HIV prevalence is high among transgender women (TW), but how HIV is transmitted to this population is not well understood. This analysis aims to characterize sexual partners of TW (PTW) to understand how their behavior contributes to HIV risk among TW. We examined baseline data from TW, PTW, and men who have sex with men (MSM) from a treatment-as-prevention study in Lima, Peru. Individual and partnership characteristics were compared across groups, and Poisson regression was used to calculate prevalence ratios for associations between sexual concurrency and potential correlates. We found that 81% of PTW had no cisgender male partners. Prevalence of alcohol dependency, concurrency, and condomless anal intercourse was high and HIV testing was low compared to the other groups. Our results suggest that PTW are a distinct population from MSM and TW, engage in behavior associated with HIV transmission, and are likely not well reached by HIV prevention interventions.

Individual and Relationship Predictors of Couple-Level Sexual Concurrency in Heterosexual South African Couples.

One of the major goals of couple-based HIV prevention programs in sub-Saharan Africa is to reduce outside sex partners, known as sexual concurrency. This cross-sectional study examined sexual concurrency at the couple-level and differentiated couples based on whether neither, one, or both partners engaged in sexual concurrency over the past 6 months. Individual predictors (alcohol use and lifetime history of physical or sexual trauma) and relationship predictors (mistrust, relationship inequity, relationship satisfaction, and sexual satisfaction) were used as predictors of couple-level sexual concurrency. A quantitative investigation using path analysis was carried out with data collected from 286 South African heterosexual couples. Results showed that alcohol use for both sexes, relationship dissatisfaction for women, and mistrust among women were predictive of different types of sexual concurrency. Findings suggest that consideration of the experiences and behavior of both partners may be useful in understanding different reasons for engagement in sexual concurrency.

A qualitative study of attitudes towards, typologies, and drivers of concurrent partnerships among people of black Caribbean ethnicity in England and their implications for STI prevention.

BACKGROUND: Partner concurrency, (having sexual partnerships overlapping in time), especially when condoms are not used, can facilitate sexually transmitted infections (STI) transmission. In Britain, STI diagnoses rates and the reporting of concurrency are higher among black Caribbeans than other ethnic groups. We explored attitudes towards, drivers, characteristics, and contexts of concurrent partnerships, and their implications for STI risk among black Caribbeans in England. METHODS: Purposive sampling, by sex and age-groups, was used to recruit participants (overall n = 59) from five sexual health clinics and community settings in London and Birmingham, England. Audio-recorded four focus group discussions (n = 28 participants), and in-depth interviews (n = 31) were conducted (June 2014-December 2015). Transcribed data were thematically analysed using Framework Analysis. RESULTS: 'Main plus' and 'non-main' concurrency were identified in this population. Main plus concurrency involves an individual having a main partner with whom s/he has a "relationship" with, and the individual and/or their partner secretly or explicitly have other non-main partners. In contrast, non-main concurrency entails having multiple, non-committed partners overlapping in time, where concurrency is usually taken as a given, making disclosure to partners irrelevant. While main partnerships were usually long-term, non-main partnerships ranged in duration from a single event through to encounters lasting several months/years. Condomless sex was common with ex/long-term/married/cohabiting partners; whereas condoms were typically used with non-main partners. However, condom use declined with partnership duration and familiarity with partners. Awareness of partners' concurrency facilitated condom use, STI-testing, and partner notification. While unresolved feelings, or sharing children with ex-partners, usually facilitated main plus concurrency; non-main concurrency was common among young, and single people. Gender norms, notions of masculinity, and sexual desires influenced concurrency. Black Caribbean popular music, social media, peer pressure, and relationship norms among black Caribbeans were also perceived to encourage concurrency, especially among men and young people. CONCLUSIONS: Concurrency among black Caribbeans is shaped by a complex interaction between emotional/psychological, interpersonal, sociocultural, and structural factors. Concurrency type, its duration, and awareness influence sexual health choices, and thus STI risk in this population. Collecting these data during clinic consultations could facilitate offering partner notification methods tailored to concurrency type. Gender- and age-specific, culturally-sensitive interventions addressing STI risks associated with concurrency are needed.

[On the issue of personnel support of medical organizations in conditions of structural transformation of health care system of the City of Moscow].

The article presents the results of analysis of the number and structure of physicians and specialists with secondary medical education in the Moscow health care system. The results of study demonstrated that in 2019, the support of the population with physicians and specialists with secondary medical education decreased as compared with 2014 from 39.4 to 37.1 and from 74.2 to 55.7 (per 10 thousand people) respectively. The number of occupied medical positions increased from 84.6% in 2014 to 87% in 2019, the staffing rates (for occupied positions of secondary medical personnel) also increased from 84.9% to 87.4 %. It was established that the staffing of individuals, both for physicians and paramedical personnel, increased from 66.8% to 79.8% and from 69.4% to 79.0%, respectively. The concurrency coefficient was 1.1 (for medical positions and positions of secondary medical personnel). The issues related to low staffing levels and high co-employment rates for individual medical positions and positions of secondary medical personnel require further resolution.

Sexual Concurrency and Contraceptive Use Among Young Adult Women.

Leveraging 2.5 years of weekly data from the Relationship Dynamics and Social Life Study, we investigate the relationship between young women's sexual concurrency and their contraceptive behavior. Specifically, we (1) examine whether young women changed their contraceptive use when switching from one to multiple concurrent sexual partners in the same week; (2) explore the uniformity of contraceptive responses to concurrency across relationship context; and (3) compare the contraceptive behaviors of never-concurrent women with those of ever-concurrent women in weeks when they were not concurrent. Nearly one in five sexually active young women had sex with two or more people in the same week. When they were concurrent, these women's odds of using any contraception increased threefold, and their odds of using condoms increased fourfold. This pattern of contraceptive adjustments was the same across relationship characteristics, such as duration and exclusivity. Yet when they were not concurrent, ever-concurrent women were less likely to use any contraception and used condoms less consistently than women who were never concurrent. We discuss these findings in the context of ongoing debates about the role of sexual concurrency in STI transmission dynamics.

Differential sexual network connectivity offers a parsimonious explanation for population-level variations in the prevalence of bacterial vaginosis: a data-driven, model-supported hypothesis.

BACKGROUND: The prevalence of bacterial vaginosis (BV) and vaginal microbiota types varies dramatically between different populations around the world. Understanding what underpins these differences is important, as high-diversity microbiotas associated with BV are implicated in adverse pregnancy outcomes and enhanced susceptibility to and transmission of sexually transmitted infections. MAIN TEXT: We hypothesize that these variations in the vaginal microbiota can, in part, be explained by variations in the connectivity of sexual networks. We argue: 1) Couple-level data suggest that BV-associated bacteria can be sexually transmitted and hence high sexual network connectivity would be expected to promote the spread of BV-associated bacteria. Epidemiological studies have found positive associations between indicators of network connectivity and the prevalence of BV; 2) The relationship between BV prevalence and STI incidence/prevalence can be parsimoniously explained by differential network connectivity; 3) Studies from other mammals are generally supportive of the association between network connectivity and high-diversity vaginal microbiota. CONCLUSION: To test this hypothesis, we propose a combination of empirical and simulation-based study designs.

But Everyone is Doing It (Sort of)! Perceived Sexual Risks in the Social Environment and the Impact on Homeless Youth Engagement in Concurrent Sexual Relationships.

Although homeless youth are likely to engage in concurrent sexual relationships and doing so can accelerate HIV transmission, the issue of sexual concurrency (i.e., having sexual partnerships that overlap in time) has received scarce attention in this vulnerable population. The literature that exists tends to focus on individuals' characteristics that may be associated with concurrency and overlooks the influence of their social environment. Informed by the risk amplification and abatement model (RAAM), this study explored the association between pro-social and problematic social network connections, and sexual concurrency among homeless youth using drop-in center services (N = 841). Nearly 37% of youth engaged in concurrency. Partially consistent with the RAAM, regression analyses showed that affiliation with more problematic ties (i.e., having more network members who practice concurrency and unprotected sex) was associated with greater sexual concurrency. Programs addressing HIV risk among homeless youth in drop-in centers should consider the role youths' network composition may play in concurrency.

The role of sexual networks in studies of how BV and STIs increase the risk of subsequent reinfection.

Prior studies have demonstrated that both bacterial vaginosis (BV) and sexually transmitted infections (STIs) are strong independent risk factors for subsequent STI. In observational studies of this biological enhancement (BE) hypothesis, it is important to adjust for the risk of STI exposure so that the independent effect of BE can be assessed. We sought to model if two markers of local sexual network (partner concurrency and cumulative number of STIs) represented residual confounding in the models of risk for subsequent infection in a study that screened 3620 women for STIs every 3 months for a year. Mixed-effects logistic regression was used to calculate the odds ratios for an incident diagnosis of Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and BV following a diagnosis of any of these four at the prior visit, controlling for the cumulative number of STIs and partner concurrency variables. We found that partner concurrency and cumulative number of STIs were each associated with incident infection, and in general, controlling for these variables reduced the strength of the association between prior and incident infections. We conclude that the frequently found association between prior and incident STIs is associated with both BE and sexual network structure.

The Association Between Men's Concern About Demonstrating Masculine Characteristics and Their Sexual Risk Behaviors: Findings from the Dominican Republic.

Quantitative analyses exploring the relationship between masculinities and men's sexual risk behaviors have most commonly used one dimension of masculinities: men's gender ideology. Examining other dimensions may enhance our understanding of and ability to intervene upon this relationship. In this article, we examined the association between gender role conflict/stress (GRC/S)-men's concern about demonstrating masculine characteristics-and three different sexual risk behaviors (having two or more sex partners in the last 30 days; never/inconsistent condom use with non-steady partners; and drinking alcohol at last sex) among a sample of heterosexual men in the Dominican Republic who were participating in an HIV prevention intervention (n = 293). The GRC/S Scale we used was adapted for this specific cultural context and has 17 items (α = 0.75). We used logistic regression to assess the relationship between GRC/S and each sexual behavior, controlling for sociodemographic characteristics. In adjusted models, a higher GRC/S score was significantly associated with increased odds of having two or more sex partners in the past 30 days (AOR 1.33, 95 % CI 1.01-1.74), never/inconsistent condom use with non-steady partners (AOR 1.45, 95 % CI 1.04-2.01), and drinking alcohol at last sex (AOR 1.56, 95 % CI 1.13-2.17). These results highlight the importance of expanding beyond gender ideology to understanding the influence of GRC/S on men's sexual risk behaviors. Interventions should address men's concern about demonstrating masculine characteristics to reduce the social and internalized pressure men feel to engage in sexual risk behaviors.

Sexual Partner Concurrency Among Partners Reported by MSM with Recent HIV Infection.

We examined concurrency among sexual partners reported by men who have sex with men (MSM) with recent (acute or early) HIV infection in San Diego, California (2002-2015). Partners overlapping in time in the past 3 months were considered concurrent. Logistic generalized linear mixed models were used to identify factors associated with concurrency at the partner-level. 56% (388/699) of partners were concurrent to ≥1 other partner. The odds of concurrency were higher among partners >10 years younger than the participant (vs. within 10 years of age) [adjusted odds ratio (AOR) = 2.22, 95% confidence interval (CI) 1.09-4.52], longer term partners (AOR per month = 1.02, 95% CI 1.01-1.03), and partners met online (AOR = 1.56, 95% CI 0.98-2.48). Concurrency is common among partners of recently HIV-infected MSM. Tailored HIV prevention strategies for MSM with older partners, longer term partners, and partners met online may help minimize the potential impact of concurrency on HIV transmission.

Psychological Distress Moderates the Intention-Behavior Association for Sexual Partner Concurrency Among Adults.

Research suggests that intentions are an important determinant of sexual risk behavior. However, this association is often weaker than hypothesized. This research investigated whether psychological distress (i.e., depression, anxiety) can help to explain the intentions-behavior gap. We used data from 397 patients seeking care at an STI clinic to test whether the association between partner concurrency intentions and behavior 3 months later was moderated by distress. Intentions predicted concurrency behavior only among less-distressed individuals; however, exploratory analyses for condom use did not demonstrate this effect. Comprehensive sexual health intervention programs should address affective determinants of risk behavior.

'Good culture, bad culture': polygyny, cultural change and structural drivers of HIV in Papua New Guinea.

Culture is often problematised as a key structural driver of HIV transmission in Papua New Guinea. Official HIV programmes, as well as church teachings, tend to focus on customary marital practices of polygyny and bride price payments as 'harmful traditions'. This focus can oversimplify the effects of current and historical nuances of cultural, political and economic change on sexual concurrency and gender inequality. Community-based healthcare workers in Southern Highlands Province explain that customary marital practices are now highly reconfigured from their traditional forms. A recent mining boom has financially advantaged local and travelling men, who are driving an increase of sexual concurrency, transactional sex and inflation of bride price payments. Healthcare workers suggest that the erosion of important social relationships and kinship obligations by the expanding cash economy has caused an intensification of individual male power while enhancing the vulnerability of women. Yet without the means to challenge the effects of uneven economic development, healthcare workers are left to target 'culture' as the central influence on individual behaviours. A commitment to address structural inequality by political leadership and in HIV prevention programmes and a careful contextualisation of cultural change is needed.

Partnership duration, concurrency, and HIV in sub-Saharan Africa.

A widely accepted explanation for the exceptionally high HIV prevalence in sub-Saharan Africa is the practice of long-term overlapping heterosexual partnering. This article shows that long-duration concurrent partnering can be protective against HIV transmission rather than promoting it. Monogamous partnering prevents sexual transmission to anyone outside the partnership and, in an initially concordant-seronegative partnership, prevents sexual acquisition of HIV by either partner. Those protections against transmission and acquisition last as long as the partnership persists without new outside partnerships. Correspondingly, these two protective effects characterise polygynous partnerships, whether or not the polygyny is formal or informal, until a partner initiates a new partnership. Stable and exclusive unions of any size protect against HIV transmission, and more durable unions provide a longer protective effect. Survey research provides little information on partnership duration in sub-Saharan Africa and sheds no light on the interaction of duration, concurrency, and HIV. This article shows how assumptions about partnership duration in individual-based sexual-network models affect the contours of simulated HIV epidemics. Longer mean partnership duration slows the pace at which simulated epidemics grow. With plausible assumptions about partnership duration and at levels of concurrency found in the region, simulated HIV epidemics grow slowly or not at all. Those results are consistent with the hypothesis that long-duration partnering is protective against HIV and inconsistent with the hypothesis that long-term concurrency drives the HIV epidemics in sub-Saharan Africa.

Measuring concurrency using a joint multistate and point process model for retrospective sexual history data.

Understanding the impact of concurrency, defined as overlapping sexual partnerships, on the spread of HIV within various communities has been complicated by difficulties in measuring concurrency. Retrospective sexual history data consisting of first and last dates of sexual intercourse for each previous and ongoing partnership is often obtained through use of cross-sectional surveys. Previous attempts to empirically estimate the magnitude and extent of concurrency among these surveyed populations have inadequately accounted for the dependence between partnerships and used only a snapshot of the available data. We introduce a joint multistate and point process model in which states are defined as the number of ongoing partnerships an individual is engaged in at a given time. Sexual partnerships starting and ending on the same date are referred to as one-offs and modeled as discrete events. The proposed method treats each individual's continuation in and transition through various numbers of ongoing partnerships as a separate stochastic process and allows the occurrence of one-offs to impact subsequent rates of partnership formation and dissolution. Estimators for the concurrent partnership distribution and mean sojourn times during which a person has k ongoing partnerships are presented. We demonstrate this modeling approach using epidemiological data collected from a sample of men having sex with men and seeking HIV testing at a Los Angeles clinic. Among this sample, the estimated point prevalence of concurrency was higher among men later diagnosed HIV positive. One-offs were associated with increased rates of subsequent partnership dissolution. Copyright © 2016 John Wiley & Sons, Ltd.