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PLOS Medicine editors and guest editors announce a call for papers for submissions for a special issue on diabetes prevention. [ABSTRACT FROM AUTHOR]

The objective of a genome-wide association study (GWAS) is to associate subsequences of individuals’ genomes to the observable characteristics called phenotypes (e.g., high blood pressure). Motivated by the GWAS problem, in this paper we introduce the information-theoretic problem of associated subsequence retrieval, where a dataset of N (possibly high-dimensional) sequences of length G, and their corresponding observable (binary) characteristics is given. The sequences are chosen independently and uniformly at random from $\mathcal {X}^{\text {G}}$ , where $\mathcal {X}$ is a finite alphabet. The observable (binary) characteristic is only related to a specific unknown subsequence of length $L$ of the sequences, called associated subsequence. For each sequence, if the associated subsequence of it belongs to a universal finite set, then it is more likely to display the observable characteristic (i.e., it is more likely that the observable characteristic is one). The goal is to retrieve the associated subsequence using a dataset of N sequences and their observable characteristics. We demonstrate that as the parameters N, G, and L grow, a threshold effect appears in the curve of probability of error versus the rate which is defined as ${{\it\text { Gh}}(\text {L}/\text {G})}/{\text {N}}$ , where $\text {h}(\cdot)$ is the binary entropy function. This effect allows us to define the capacity of associated subsequence retrieval. We develop an achievable scheme and a matching converse for this problem, and thus characterize its capacity in two scenarios: the zero-error-rate and the $\epsilon $ -error-rate. [ABSTRACT FROM AUTHOR]

In recent years, we have witnessed the explosion of large-scale data in various fields. Classical statistical methodologies, such as linear regression or generalized linear regression, often show inadequate performance on heterogeneous data because the key homogeneity assumption fails. In this paper, we present a flexible framework to handle heterogeneous populations that can be naturally grouped into several ordered subtypes. A local model technique utilizing ordinal class labels during the training stage is proposed. We define a new “progression score” that captures the progression of ordinal classes, and use a truncated Gaussian kernel to construct the weight function in a local regression framework. Furthermore, given the weights, we apply sparse shrinkage on the local fitting to handle high dimensionality. In this way, our local model is able to conduct variable selection on each query point. Numerical studies show the superiority of our proposed method over several existing ones. Our method is also applied to the Alzheimer’s Disease Neuroimaging Initiative data to make predictions on the longitudinal clinical scores based on different modalities of baseline brain image features. [ABSTRACT FROM AUTHOR]

Introduction: High incidence of HIV infection among adolescent girls and young women (AGYW) has been attributed to the numerous and often layered vulnerabilities that they encounter including violence against women, unfavourable power relations that are worsened by age-disparate sexual relations, and limited access to sexual and reproductive health information and services. For AGYW living in urban informal settlements (slums), these vulnerabilities are compounded by pervasive poverty, fragmented social networks, and limited access to social services including health and education. In this paper, we assess sexual risk behaviours and their correlates among AGYW in two slum settlements in Nairobi, Kenya, prior to the implementation of interventions under the Determined Resilient Empowered AIDS-free Mentored and Safe (DREAMS) Partnership. Methods: We drew on secondary data from the Transition to Adulthood study, the most recent representative study on adolescent sexual behaviour in the two settlements. The study was nested within the Nairobi Urban Health and Demographic Surveillance System (NUHDSS). Data were collected in 2009 from 1,390 AGYW aged 12–23 years. We estimated the proportions of AGYW reporting ever tested for HIV, condom use, multiple sexual partners and age-disparate sex by socio-demographic characteristics. “High risk” sexual behaviour was defined as a composite of these four variables and age at first sex. Multivariable regression analyses were performed to identify factors associated with risk behaviours. Results: Fifty-one percent of AGYW reported that they had ever tested for HIV and received results of their last test, with the proportion rising steeply by age (from 15% to 84% among those <15 years and 20–23 years, respectively). Of 578 AGYW who were sexually active in the 12 months preceding the survey, 26% reported using a condom at last sex, 4% had more than one sexual partner, and 26% had sex with men who were at least 5 years older or younger. All girls aged below 15 years who had sex (n = 9) had not used condoms at last sex. The likelihood of engaging in “high risk” sexual risk behaviour was higher among older AGYW (19–23 years), those in marital unions, of Luo ethnicity, out of school, living alone or with a friend (versus parents), living with spouse (versus parents), and those whose friends engaged in risky/anti-social behaviours. In contrast, Muslim faith, co-residence with both parents, and belonging to an organised social group were associated with lower odds of risky sexual behaviours. Conclusion: Our study findings suggest that multifaceted approaches addressing the educational and social mediators of AGYW’s vulnerability and that also reach the people with whom AGYW live and interact, are needed to reduce the rapid onset of sexual risk during the adolescent years. There is a particular need to reach the youngest adolescent girls in poor urban settings, among whom condom use and awareness of HIV status is rare. [ABSTRACT FROM AUTHOR]

Objective and the context: This paper examines the beliefs and experiences of women and their families in remote mountain villages of Nepal about perinatal sickness and death and considers the implications of these beliefs for future healthcare provision. Methods: Two mountain villages were chosen for this qualitative study to provide diversity of context within a highly disadvantaged region. Individual in-depth interviews were conducted with 42 women of childbearing age and their family members, 15 health service providers, and 5 stakeholders. The data were analysed using a thematic analysis technique with a comprehensive coding process. Findings: Three key themes emerged from the study: (1) ‘Everyone has gone through it’: perinatal death as a natural occurrence; (2) Dewata (God) as a factor in health and sickness: a cause and means to overcome sickness in mother and baby; and (3) Karma (Past deeds), Bhagya (Fate) or Lekhanta (Destiny): ways of rationalising perinatal deaths. Conclusion: Religio-cultural interpretations underlie a fatalistic view among villagers in Nepal’s mountain communities about any possibility of preventing perinatal deaths. This perpetuates a silence around the issue, and results in severe under-reporting of ongoing high perinatal death rates and almost no reporting of stillbirths. The study identified a strong belief in religio-cultural determinants of perinatal death, which demonstrates that medical interventions alone are not sufficient to prevent these deaths and that broader social determinants which are highly significant in local life must be considered in policy making and programming. [ABSTRACT FROM AUTHOR]

Generalization is an effective technique for protecting confidential information of individuals, and has been studied by proposing numerous algorithms. However, the previous works do not separate the protection against identity disclosure and sensitive disclosure. Thus, when the requirement of attribute protection is higher than that of identity protection, generalization for $l$ -diversity causes overprotection for identity and large mounts of information utility loss. This paper presents a novel approach, called cross-bucket generalization, as a solution to meet the problem. The rationale is to divide microdata into equivalence groups and buckets. First, it provides separate protection for identity and sensitive values, and the level of protection can be flexibly adjusted based on actual demands. Second, the sizes of equivalence groups and buckets are minimized as far as possible by only satisfying the protection requirements, which avoid the overprotection for identity and reduce information loss. The experiments we conducted illustrate the effectiveness of our solution. [ABSTRACT FROM AUTHOR]

Developing interventions that address psychosocial wellbeing of people living with HIV is critical to ensure strong linkages to and retention in HIV care. This paper describes the development of Sondela, an HIV adjustment and coping intervention for heterosexual men and women living with HIV, and its relevance and feasibility in the South African context. Sondela is a six three-hour, small group-based, participatory workshop series. We followed an iterative, multi-phased process of curriculum development that involved research, theoretical frameworks and piloting. A systematic review highlighted the absence of psychosocial interventions targeting heterosexual HIV positive populations living in high HIV prevalence and resource-poor settings. Formative studies demonstrated risk and social factors associated with adjustment and coping with HIV, emphasising the need for interventions that acknowledge gendered experiences. Our pilot of Sondela demonstrated high levels of relevance and feasibility. Men appreciated the workshop “space” to openly talk about their HIV positive status and what is means for their role as partners and fathers and friends. Women valued the skills and approaches because they were relevant to “real life” situations and not just about HIV. Sondela promises to be valuable in supporting health system initiatives and psychosocial support to strengthen linkages to and retention in HIV care, and this suggests a need for rigorous evaluation of Sondela to establish evidence for its effectiveness in a general population. [ABSTRACT FROM AUTHOR]

Background: Migrants account for 35% of HIV diagnoses in the European Union (ECDC/WHO 2014). Little is known about the impact of such a lifelong infection diagnosis on lives that are already disrupted by migration. In this paper, we assess the impact of HIV diagnosis on activity, union, well-being among African migrants living in France, the second group most affected by HIV after MSM. We compare it with the impact of the diagnosis of Hepatitis B, another lifelong infection affecting African migrants. Methods: We use the ANRS PARCOURS survey, a retrospective life-event survey led in 2012–2013 in 74 health structures in Paris greater area which collected 926 life histories of Sub-Saharan migrants living with HIV and 779 with Hepatitis B. We modelled the probability year by year since 18 years of age until data collection to lose one’s activity, to experience a conjugal break up and degradation of well-being and we estimated the impact of migration and of HIV and Hepatitis B diagnoses on these probabilities, after adjustment on other factors, thanks to discrete-time logistic regressions. Results: Migration entailed loss of activity and conjugal break up, though HIV diagnosis after migration did not statistically impact on these outcomes. Yet HIV diagnosis had a massive negative impact on well-being (aOR = 11.31 [4.64–27.56] for men and 5.75 [2.79–11.86] for women). This negative impact on well-being tended to diminish for persons diagnosed after 2004. The negative impact of HIV diagnosis on African migrants’ well-being seems to be attenuated in the last decade, which hints at a normalization of the subjective experience of HIV diagnosis. [ABSTRACT FROM AUTHOR]

Background: Network types and characteristics have been linked to the capacity of inter-personal environments to mobilise and share resources. The aim of this paper is to examine personal network types in relation to long-term condition management in order to identify the properties of network types most likely to provide support for those with a long-term condition. Method: A cross-sectional observational survey of people with type 2 diabetes using interviews and questionnaires was conducted between April and October 2013 in six European countries: Greece, Spain, Bulgaria, Norway, United Kingdom, and Netherlands. 1862 people with predominantly lower socio-economic status were recruited from each country. We used k-means clustering analysis to derive the network types, and one-way analysis of variance and multivariate logistic regression analysis to explore the relationship between network type socio-economic characteristics, self-management monitoring and skills, well-being, and network member work. Results: Five network types of people with long-term conditions were identified: restricted, minimal family, family, weak ties, and diverse. Restricted network types represented those with the poorest self-management skills and were associated with limited support from social network members. Restricted networks were associated with poor indicators across self-management capacity, network support, and well-being. Diverse networks were associated with more enhanced self-management skills amongst those with a long-term condition and high level of emotional support. It was the three network types which had a large number of network members (diverse, weak ties, and family) where healthcare utilisation was most likely to correspond to existing health needs. Discussion: Our findings suggest that type of increased social involvement is linked to greater self-management capacity and potentially lower formal health care costs indicating that diverse networks constitute the optimal network type as a policy in terms of the design of LTCM interventions and building support for people with LTCs. [ABSTRACT FROM AUTHOR]

Spirituality/religion serves important roles in coping, survival and maintaining overall wellbeing within African cultures and communities, especially when diagnosed with a chronic disease like HIV/AIDS that can have a profound effect on physical and mental health. However, spirituality/religion can be problematic to some patients and cause caregiving difficulties. The objective of this paper was to examine the role of spirituality/religion as a source of strength, resilience and wellbeing among sub-Saharan African (SSA) migrant women with HIV/AIDS. A qualitative study of SSA migrant women was conducted between April 2013 and December 2014. Participants were recruited through purposive sampling and snowball techniques from AIDS Reference Centres and AIDS workshops in Belgium, if they were 18 years and older, French or English speaking, and diagnosed HIV positive more than 3 months beforehand. We conducted semi-structured interviews with patients and did observations during consultations and support groups attendances. Thematic analysis was used to analyse the data. 44 women were interviewed, of whom 42 were Christians and 2 Muslims. None reported religious/spiritual alienation, though at some point in time many had felt the need to question their relationship with God by asking “why me?” A majority reported being more spiritual/religious since being diagnosed HIV positive. Participants believed that prayer, meditation, regular church services and religious activities were the main spiritual/religious resources for achieving connectedness with God. They strongly believed in the power of God in their HIV/AIDS treatment and wellbeing. Spiritual/religious resources including prayer, meditation, church services, religious activities and believing in the power of God helped them cope with HIV/AIDS. These findings highlight the importance of spirituality in physical and mental health and wellbeing among SSA women with HIV/AIDS that should be taken into consideration in providing a caring and healthy environment. [ABSTRACT FROM AUTHOR]