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Community-based question answering services accumulate large volumes of knowledge through the voluntary services of people across the globe. Stack Overflow is an example of such a service that targets developers and software engineers. In general, questions in Stack Overflow are answered in a very short time. However, we found that the number of unanswered questions has increased significantly in the past two years. Understanding why questions remain unanswered can help information seekers improve the quality of their questions, increase their chances of getting answers, and better decide when to use Stack Overflow services. In this paper, we mine data on unanswered questions from Stack Overflow. We then conduct a qualitative study to categorize unanswered questions, which reveals characteristics that would be difficult to find otherwise. Finally, we conduct an experiment to determine whether we can predict how long a question will remain unanswered in Stack Overflow.

A single dose of the oral cholera vaccine was efficacious in older children (≥5 years of age) and in adults in a setting with a high level of cholera endemicity. (Funded by the Bill and Melinda Gates Foundation and others; ClinicalTrials.gov number, NCT02027207.).

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In vivo-induced antigen technology is a method to identify proteins expressed by pathogenic bacteria during human infection. Sera from 10 patients convalescing from cholera infection in Bangladesh were pooled, adsorbed against in vitro-grown El Tor Vibrio cholerae O1, and used to probe a genomic expression library in Escherichia coli constructed from El Tor V. cholerae O1 strain N16961. We identified 38 positive clones in the screen, encoding pili (PilA and TcpA), cell membrane proteins (PilQ, MshO, MshP, and CapK), methyl-accepting chemotaxis proteins, chemotaxis and motility proteins (CheA and CheR), a quorum-sensing protein (LuxP), and four hypothetical proteins. Analysis of immune responses to purified PilA and TcpA in individual patients demonstrated that the majority seroconverted to these proteins, confirming results with pooled sera. These results suggest that PilA and its outer membrane secretin, PilQ, are expressed during human infection and may be involved in colonization of the gastrointestinal tract. These results also demonstrate substantial immune responses to TcpA in patients infected with El Tor V. cholerae O1. In vivo-induced antigen technology provides a simple method for identifying microbial proteins expressed during human infection, but not during in vitro growth. Vibrio cholerae is a Gram-negative bacillus that causes a severe, dehydrating diarrhea in humans (1). V. cholerae can be differentiated by the lipopolysaccharide in the outer membrane; strains of V. cholerae that produce cholera belong to serogroup O1 or O139. V. cholerae O1 is divided into two biotypes, classical and El Tor; the current global pandemic of V. cholerae O1 infection is caused by El Tor strains.A major virulence factor for pathogenic strains of V. cholerae is cholera toxin, a protein exotoxin that consists of a single A subunit noncovalently associated with five B subunits (2). A second major virulence factor of V. cholerae is the toxin coregulated pilus (TCP; ref. 3). TCP is essential for colonization and virulence in both mouse models of cholera (3) and human volunteer studies (4). TcpA, the 20.5-kDa major structural subunit of TCP, has homology to the type IV pili of several other bacterial pathogens (5). TcpA from El Tor and classical strains of V. cholerae show Ϸ80% protein homology; monoclonal antibodies demonstrate epitope differences between these proteins in the two biotypes (6, 7).In addition to TcpA, the V. cholerae genome encodes two other type IV pili, the mannose-sensitive hemagglutinin (MSHA) and PilA (8). MSHA is a thin, flexible pilus composed of a 17-kDa subunit (9). A strain of V. cholerae deleted in mshA showed no defect in colonization of human volunteers (10). Recently, Fullner et al. (11) described a four-gene cluster, pilABCD, encoding a third type IV pilus in V. cholerae. A deletion of pilA had no effect on colonization in infant mice. The role of PilA in human infection has not been previously examined.

Introduction:Utilization of recommended antenatal care (ANC) throughout the pregnancy period is a proven healthy behavior in reducing maternal mortalities and morbidities. The objective of this study is to identify the demand side factors that are associated with the recommended utilization of ANC services among adolescents and adult women in Bangladesh.Method:This study utilized cross-sectional data from latest Bangladesh Demographic and Health Survey 2014. Data of a total of 4626 adolescents and adult women were analyzed. Bivariate and multivariate analyses were performed for identifying the significant determining factors associated with the ANC services utilization.Results:Approximately, 32% adult and 30% adolescent women utilized the recommended ANC care. The higher educated adolescents and adult women were 8.08 times (P < .001) and 2.98 times (P < .001) more likely to receive 4 or more ANC, respectively, compared to uneducated women. The richest quintile showed higher tendency to utilize optimum ANC services and had 2.70 times (P < .05) and 6.51 times (P < .001) more likelihood to receive optimal ANC services for adolescent and adult groups, respectively, compared to poorest quintile.Conclusion:Other than education and income, several other factors including mass -media, place of residence, working status, and geographical variations were significantly associated with recommended ANC. These findings might help health-care programmers and policy makers for initiating appropriate policy and programs for ensuring optimal ANC coverage for all. Ensuring adequate ANC regardless of economic status and residence of pregnant women could guarantee universal maternal health-care coverage as devoted to a national strategic guideline.

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Background: There is increasing concern around the use of antibiotics in animal food production and the risk of transmission of antimicrobial resistance within the food chain. In many low and middle-income countries, including Bangladesh, the commercial poultry sector comprises small-scale producers who are dependent on credit from poultry dealers to buy day-old chicks and poultry feed. The same dealers also supply and promote antibiotics. The credit system is reliant upon informal relationships among multiple actors as part of social capital. This paper aims to describe dependencies and relationships between different actors within unregulated broiler poultry production systems to understand the social and contextual determinants of antibiotic use in low-resource settings. Methods: We used a cross-sectional qualitative design including in-depth interviews among purposefully selected commercial poultry farmers (n = 10), poultry dealers (n = 5), sales representatives of livestock pharmaceutical companies (n = 3) and the local government livestock officer as a key-informant (n = 1). We describe the food production cycle and practices relating to credit purchases and sales using social capital theory. Findings: Poultry dealers provide credit and information for small-scale poultry farmers to initiate and operate their business. In return for credit, farmers are obliged to buy poultry feed and medicine from their dealer and sell their market-ready poultry to that same dealer. All farms applied multiple antibiotics to poultry throughout the production cycle, including banned antibiotics such as colistin sulfate. The relationship between dealers and poultry farmers is reciprocal but mostly regulated by the dealers. Dealers were the main influencers of decision-making by farmers, particularly around antibiotic use as an integral part of the production cycle risk management. Our findings suggest that strategies to improve antibiotic stewardship and responsible use should exploit the patron-client relationship which provides the social and information network for small-scale farmers. Masud et al. Antibiotic Use in Poultry Production Conclusion: Social capital theory can be applied to the patron-client relationship observed among poultry farmers and dealers in Bangladesh to identify influences on decision making and antibiotic use. Within unregulated food production systems, strategies to promote the prudent use of antibiotics should target commercial feed producers and livestock pharmaceutical manufacturers as a first step in developing a sustainable poultry value chain.