Employment status,material hardship,and mental health among low-income working-age adults in South Korea

The current study examines the associations between employment status and mental health and the mediating role of material hardship among low-income households in South Korea. This study uses regression models with a rich set of control variables and lagged dependent variable models with a nationally representative sample of 1113 low-income working-age household heads from the Korean Welfare Panel Study (KOWEPS). We find that the nonstandard employment and unemployment statuses are associated with a higher level of depression and a lower level of self-esteem, when compared to a standard employment status. These negative associations are partially mediated by an increased material hardship risk. Policy implications to improve employment conditions and mitigate material hardship are discussed.     

Differential effects of parental control on preschool-age adjustment depending on child effortful control

This study examined whether parental control differentially predicted children's effortful control and adjustment depending on children's levels of executive control and delay ability. Using longitudinal data, the study included 241 preschool-age children and their mothers. Fifty-seven percent of the sample was lower income and included 64% White, 10% Latino/Hispanic, 9% Black, 3% Asian-American, 2% Native or American Indian, and 12% multiple racial/ethnic backgrounds. Interactions between aspects of parental and child control at 3-years-old were tested as predictors of mother-reported child effortful control at 4.5 years and teacher-reported adjustment at 5.5 years. Children's early levels of executive control and delay ability moderated the relations of some forms of parental control with child outcomes, although several hypothesized interactions were nonsignificant. Low parental autonomy respect predicted higher externalizing for children initially high in executive control but predicted lower externalizing for children initially low in executive control. Conversely, high autonomy respect predicted higher impulsivity for children low in delay ability but higher social competence for children high in delay ability. Finally, low maternal negative control predicted higher internalizing for children low in delay ability, whereas it predicted higher internalizing for children high in delay ability. These findings suggest that in some cases the type and degree of parental control should match a child's level of effortful control to support their social, emotional, and behavioral adjustment optimally.     

A LARGE-SCALE PERSONNEL ASSIGNMENT MODEL FOR THE NAVY*

The U.S. Navy has been trying for years to develop a model to automate its personnel assignment process The requirement of rotating navy personnel frequently between sea duty and shore duty in accordance with multiple policies makes modeling efforts difficult. However, without a model to optimize assignments with regard to multiple policies, navy managers do not know the real impact of personnel assignments. This limits their ability to make effective decisions. This paper summarizes our effort to develop a large-scale network model for the navy's assignment problem. The navy has accepted this model for implementation, replacing the current manual assignment process. The approach in this paper can be generalized to a wide variety of perosnnel assignment problems.     

Looked after children's right to contact with birth parents: An Australian study

In Australia, there are more than 46 000 children in out-of-home care (OOHC). Most of these children have been in OOHC for more than 2 years. Similarly, there are more than 407 000 children in the United States and over 80 800 in England who are ‘looked after’ with approximately one third of these children being in OOHC for more than 2 years. This paper concerns ‘looked after’ children's rights to contact with their birth parents. The United Nations Convention on the Rights of the Child (UNCRC) requires child protection systems to recognize the rights of children to maintain contact with their families except where this is not in the child's ‘best interests’. In this paper, we report on a qualitative study conducted in Australia exploring legal and family support practitioners' perceptions of barriers to contact between children in OOHC and their birth parents. The thematic analysis identified four themes: These were as follows: a focus on systems driven responses; lack of cultural recognition and responsiveness; carers' disconnection from birth parents; and parents' exclusion. We discuss the implications of these findings for understanding and recognizing children's right to contact with birth parents.     

Recommended Reference Values for Risk Assessment of Oral Exposure to Copper

The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) database, the authoritative source of U.S. risk assessment toxicity factors, currently lacks an oral reference dose (RfD) for copper. In the absence of such a value, various health-based reference values for copper are available for use in risk assessment. We summarize the scientific bases and differences in assumptions among key reference values for ingested copper to guide selection of appropriate values for risk assessment. A comprehensive review of the scientific literature best supports the oral RfD of 0.04 mg/kg body weight/day derived by EPA from their Drinking Water Action Level. This value is based on acute gastrointestinal effects but is further supported by broader analysis of copper deficiency and toxicity.     

Media exposure,threat processing,and mitigation behaviors in Gulf Coast residents facing the co-occurring threats of COVID-19 and hurricanes

The 2020 hurricane season threatened millions of Americans concurrently grappling with COVID-19. Processes guiding individual-level mitigation for these conceptually distinct threats, one novel and chronic (COVID-19), the other familiar and episodic (hurricanes), are unknown. Theories of health protective behaviors suggest that inputs from external stimuli (e.g., traditional and social media) lead to threat processing, including perceived efficacy (self- and response) and perceived threat (susceptibility and severity), guiding mitigation behavior. We surveyed a representative sample of Florida and Texas residents (N = 1846) between April 14, 2020 and April 27, 2020; many had previous hurricane exposure; all were previously assessed between September 8, 2017 and September 11, 2017. Using preregistered analyses, two generalized structural equation models tested direct and indirect effects of media exposure (traditional media, social media) on self-reported (1) COVID-19 mitigation (handwashing, mask-wearing, social distancing) and (2) hurricane mitigation (preparation behaviors), as mediated through perceived efficacy (self- and response) and perceived threat (susceptibility and severity). Self-efficacy and response efficacy were associated with social distancing (p = .002), handwashing, mask-wearing, and hurricane preparation (ps < 0.001). Perceived susceptibility was positively associated with social distancing (p = 0.017) and hurricane preparation (p < 0.001). Perceived severity was positively associated with social distancing (p < 0.001). Traditional media exhibited indirect effects on COVID-19 mitigation through increased response efficacy (ps < 0.05), and to a lesser extent self-efficacy (p < 0.05), and on hurricane preparation through increased self-efficacy and response efficacy and perceived susceptibility (ps < 0.05). Social media did not exhibit indirect effects on COVID-19 or hurricane mitigation. Communications targeting efficacy and susceptibility may encourage mitigation behavior; research should explore how social media campaigns can more effectively target threat processing, guiding protective actions.     

Modeling undetected live type 1 wild poliovirus circulation after apparent interruption of transmission: Pakistan and Afghanistan

Since 2013, wild poliovirus (WPV) transmission occurred only for type 1 (WPV1). Following several years of increasing reported incidence (2017–2019) and programmatic disruptions caused by COVID-19 (early 2020), Pakistan and Afghanistan performed a large number of supplementary immunization activities (late 2020–2021). This increased intensity of immunization, following widespread transmission, substantially decreased WPV1 cases and positive environmental samples during 2021. Modeling the potential for undetected circulation of WPV1 after apparent interruption can support regional and global decisions about certification of the eradication of indigenous WPV1 transmission. We apply a stochastic model to estimate the confidence about no circulation (CNC) of WPV1 in Pakistan and Afghanistan as a function of time since the last reported case and/or positive environmental sample. Exploration of different assumptions about surveillance quality suggests a range for CNC for WPV1 as a function of time since the last positive surveillance signal, and supports the potential use of a time with no evidence of transmission of less than 3 years as sufficient to assume die out in the context of good acute flaccid paralysis (AFP) surveillance. We show high expected CNC based on AFP surveillance data alone, even with imperfect surveillance and some use of inactivated poliovirus vaccine masking the ability of AFP surveillance to detect transmission. Ensuring high quality AFP and environmental surveillance may substantially shorten the time required to reach high CNC. The time required for high CNC depends on whether immunization activities maintain high population immunity and the quality of surveillance data.     

MODELING LEARNING CURVE AND LEARNING COMPLEMENTARITY FOR RESOURCE ALLOCATION AND PRODUCTION SCHEDULING*

Research on learning effects in mathematical programming models for optimum resource allocation has called attention to the difficulty in solving such models in their original nonlinear form. In this paper, systematically varying sizes of linear segments are designed to approximate productivity changes along the learning curve, and a single separable linear programming model is developed. With production complementarity and learning transmission between products, a more realistic resource allocation and production scheduling problem emerges. Two cases of learning transmissions are considered, and the model design process, which defines a decision problem that can be solved by a simplex algorithm, is demonstrated.