The matching extension problem in general graphs is co-NP-complete

A simple connected graph G with 2n vertices is said to be k-extendable for an integer k with \(0<k<n\) if G contains a perfect matching and every matching of cardinality k in G is a subset of some perfect matching. Lakhal and Litzler (Inf Process Lett 65(1):11–16, 1998) discovered a polynomial algorithm that decides whether a bipartite graph is k-extendable. For general graphs, however, it has been an open problem whether there exists a polynomial algorithm. The new result presented in this paper is that the extendability problem is co-NP-complete.     

The effects of social and political openness on the welfare state in 18 OECD countries

Studies examining the relationship between globalisation and the welfare state tend to focus on the effects of economic dimensions of globalisation, the extent to which a country is part of the world market. Globalisation also has social and political dimensions and the effects of these on welfare states – in terms of social security transfers and generosity – are studied in this article. Data from the KOF Index of Globalisation , the OECD Historical Statistics and the Comparative Welfare Entitlements Dataset are used to analyse the effects of social and political openness on the welfare states of 18 countries of the Organisation for Economic Cooperation and Development between 1970 and 2000. The analyses show that social security transfers and generosity have increased less in countries with the highest increase in social openness and that the welfare state is not affected by political openness.     

Screening for pediatric bipolar disorder in primary care

A child or adolescent with pediatric bipolar disorder (PBD) is at higher risk for suicide, violence, and impaired psychosocial functioning. The prevalence of diagnosed PBD has increased 40-fold in less than 2 decades, leading some to believe that PBD is inaccurately diagnosed. Complicating this issue, disagreements exist among clinicians as to the utility of current screening methods. The assessment picture is further muddied by the high rate of comorbid psychiatric conditions. A literature review was performed to describe the present understanding of PBD and identify current practices of screening for the disorder. Although screening tools are available, the literature suggests they lack validity. Awareness, a thorough interview, and expedient referral may assist clinicians in making a correct diagnosis. Accurate assessment will help ease the psychological and economic burden of PBD.     

Psychological Distress,Couple Interactions,and Parenting: A Dyadic Analysis of African American Couples

Parental depression is a well‐established risk factor for couple conflict and ineffective or hostile parenting (M. C. Lovejoy, P. A. Graczyk, E. O'Hare, & G. Neuman, 2000; L. M. Papp, M. C. Goeke‐Morey, & E. M. Cummings, 2007). Although research suggests that caregiver depression may impact parenting indirectly via increased conflict between couples (e.g., R. D. Conger et al., 2002), few studies take into account the behaviors of both caregivers in exploring these relations. The goal of the current study is to employ an actor–partner mediator model to examine the complex relations among psychological distress, negative couple interactions, and parenting. Using a sample of 162 African American couples with children, we find evidence that the psychological distress of each caregiver has an effect on couple interactions for both men and women. The effects from each caregivers' distress to parenting are mainly indirect through the interactional behaviors of the mother toward the father, consistent with the father vulnerability hypothesis (e.g., E. M. Cummings, M. Goeke‐Morey, & J. Raymond, 2004).     

Bilateral Donors' Efforts to Assess and Manage UN Agencies' Effectiveness: Seeking a Balance between Paris Principles and Domestic Accountability

Since the turn of the century, results orientation and performance measurement have become buzzwords in development aid. Bilateral donors are increasingly concerned about the effectiveness of core‐funded UN specialised agencies, funds and programmes, through which they channel a substantial part of their funds. While the logic for increased monitoring is clear, it is less evident how to assess this information for purposes of accountability, performance‐based funding and governance. This article describes the general evolution in this area and discusses two major initiatives to harmonise and align bilateral assessments, using case‐study material from three bilateral donors (Belgium, the Netherlands and the UK) with clearly diverging performance‐management cultures, and exploring the extent to which they rely upon joint and aligned initiatives.     

Problem Gambling and Delinquent Behaviours Among Adolescents: A Scoping Review

Despite many studies indicating an association between problem gambling and delinquent behaviours among adolescents, there has been no effort to systematically analyze the state of the literature on this relationship. To fill this gap, we conducted a scoping review of the literature published between 2000 and 2016 on problem gambling and delinquent behaviours among adolescents. We searched twelve databases and reviewed reference lists to identify eligible studies. Search terms included a combination of medical subject headings and keywords for gambling, youth, and delinquency, which were combined with the Boolean operator “AND”. 1795 studies were identified through the literature search. Nine studies were eligible for inclusion. All of the studies were conducted in North America, with primarily male participants, and most of the data were cross-sectional. No qualitative studies met the inclusion criteria. Screening tools used to measure problem gambling were inconsistent, making comparisons across studies difficult. We found a consistent moderate to strong association between problem gambling and delinquent behaviour. Only one study presented associations by socio-economic status and none considered gender, sex or ethnic differences. Studies in the review showed that problem gambling is associated with both violent and non-violent behaviours among adolescents. These associations may suggest that problem gambling and delinquent behaviours have common risk factors and reflect a syndrome of risky behaviours best targeted through prevention and treatment that is holistic and considers the context in which the youth is situated. Further research is warranted to better understand the relationship between problem gambling and delinquent behaviours.     

Environmental Risk Exposure,Risk Perception,Political Ideology and Support for Climate Policy

The degree to which risk perceptions are socially constructed versus the result of actual exposure to risk is highly contested; how risk exposure and risk perception influence policy attitudes is also poorly understood. We examine how personal exposure to risk factors impacts risk perceptions and policy support related to air pollution and climate change. Our selection of risk exposure variables is informed by the “mental models” literature, and we employ an array of variables to capture subjective risk perceptions using novel survey data. We find that exposure to risk does little to predict risk perception and has a small influence on policy support. Overall, our findings lend support to a constructionist understanding of risk perception and support for policies related to environmental risks.     

Unplanned sexual activity as a consequence of alcohol use: a prospective study of risk perceptions and alcohol use among college freshmen

OBJECTIVE: The authors' goal was to show how risk perceptions regarding unplanned sexual activity following alcohol use are prospectively related to subsequent alcohol consumption. PARTICIPANTS: Undergraduate students (N = 380) completed questionnaires at 2 time points during their freshman year. METHODS: In the middle of the academic year (T1), students estimated their risk of engaging in unplanned sex and reported their alcohol use during the previous term. Four months later (T2), they again reported alcohol use and indicated whether they had engaged in unplanned sex since T1. RESULTS: Students who consumed more alcohol at T1 rated their risk of unplanned sex more highly, suggesting relative accuracy. Those with higher risk perceptions consumed more alcohol at T2 (controlling for T1 use), suggesting that they maintained the high-risk behavior. Last, those who were unrealistically optimistic (ie, estimated low risk at T1 yet had unplanned sex by T2) reported greater alcohol use at T2. CONCLUSIONS: These findings highlight the role that risk perceptions regarding sexual activity may play in college students' alcohol use.