Data relaying with constraints in hierarchical sensor networks

In this paper we present and discuss several optimisation problems that arise in the management of data flow in wireless sensor networks (WSNets). We consider a hierarchical architecture for WSNets composed of sensors, relays, and relay gateways. Sensors send data they generate at a known average bit rate to relays in one hop. The relay nodes use a multi-hop mechanism to reach a set of assigned gateways which then forward the data directly to the base station. We are concerned with finding an assignment of relay gateways to relays so that certain constraints are satisfied. We define a unified model in which constraints such as lifetime, data delay, and data flow splitting are formulated in terms of four optimisation problem in graphs.     

Gender,gambling settings and gambling behaviours among undergraduate poker players

A gender divide in gambling is commonly observed among college populations. This study examines whether settings where students gamble on poker mediate the relationship between gender and poker gambling behaviours. Undergraduate poker players, 126 females and 242 males, were randomly sampled from three universities in Montreal, Canada. Three outcomes measuring risky behaviours were considered: severity of gambling problems as measured by the Problem Gambling Severity Index (PGSI), past-year poker spending and past-year poker debt. Multiple mediation analyses were conducted. The effect of gender on outcomes was analysed through three putative mediators: gambling on poker in private residences, in public locations or on the Internet. Male gender positively relates to risky gambling behaviours and occurrence of gambling in various settings. Risky gambling behaviours are positively related to gambling in various settings. Overall, the occurrence of playing poker in public locations and on the Internet emerged as significant mediators in relation to PGSI score, past-year poker spending and past-year poker debt. Given the nature of the processes by which gender is related to risky gambling behaviours among undergraduate students, gambling needs to be understood through a perspective that focuses as much on contexts as it does on individuals.     

Gambling Patterns and Problems of Gamblers on Licensed and Unlicensed Sites in France

In 2010 France enacted a law to regulate supply and consumption of online gambling. Its primary aim was to protect citizens from gambling-related harm. This study aims to assess differences in gambling patterns and related harm between online gamblers who use licensed versus unlicensed sites. Participants (N = 3860) completed a self-administered online survey on gambling practices. Pairwise logistic regressions examined the association between the legal statuses of gambling sites people patronized and demographic variables and gambling types. Multivariate logistic regression models explored associations between gambling patterns and related problems according to the legal status of sites people have gambled on. Overall, 53.7 % of online gamblers report gambling exclusively on licensed sites. Those who bet on regulated activities on unlicensed sites, versus licensed sites, are more likely to be female, younger, less educated, inactive in the labor market and are more likely to perceive their financial situation to be difficult. Gambling on unlicensed sites is associated with more intense gambling patterns and more gambling-related problems compared to licensed sites. Findings demonstrate that gambling activities carried out on state licensed sites are associated with less overall harm to gamblers. Implications of these findings on future policy are discussed and prospective research directions are outlined.     

Death of a child: Perspective of Chinese mothers in Singapore

The grief of Chinese mothers is examined in a phenomenological exploratory study. Grieving for the deceased child is moderated by diverse Chinese religious beliefs intertwined with cultural practices. Five aspects of grieving include giving meaning to the child’s life and death, quality and assurance of the afterlife, the function of crying, and a continuing bond. Extrapolating from the mothers’ grieving are questions related to the implications of children’s death for other family members and the significance of the interconnectedness of the self, others, the environment and the universe in processing a crisis through religion and spirituality in multicultural social work.     

An Examination of School Counselors’ Competency Working with Lesbian,Gay and Bisexual and Transgender (LGBT) Students

This study aims to investigate school counselors’ competency level in working with lesbian, gay, bisexual, transgender (LGBT) youth. Using a sample of 125 school counselors who are currently practicing in schools, this study found school counselors perceived themselves with very low competency levels. Spearman's rho correlation results indicated that only three demographic variables were significantly correlated with school counselors’ self-perceived competency level: sexual orientation, whether having received any postmasters trainings and geographic regions. Counselors identifying as nonheterosexual, those who received postmasters trainings or workshops, and those who reside in the West tend to have a higher self-perceived competency working with youth identifying as LGBT.     

Using Bayesian graphical models to model biases in observational studies and to combine multiple sources of data: application to low birth weight and water disinfection by-products

Summary.  Data in the social, behavioural and health sciences frequently come from observational studies instead of controlled experiments. In addition to random errors, observational data typically contain additional sources of uncertainty such as missing values, unmeasured confounders and selection biases. Also, the research question is often different from that which a particular source of data was designed to answer, and so not all relevant variables are measured. As a result, multiple sources of data are often necessary to identify the biases and to inform about different aspects of the research question. Bayesian graphical models provide a coherent way to connect a series of local submodels, based on different data sets, into a global unified analysis. We present a unified modelling framework that will account for multiple biases simultaneously and give more accurate parameter estimates than standard approaches. We illustrate our approach by analysing data from a study of water disinfection by-products and adverse birth outcomes in the UK.