Childhood adversity and adulthood happiness: Evidence from Japan

In this study, we examined the impact of childhood interpersonal adversity on adulthood subjective well-being, with a focus on the mediating and moderating effects of social support and socioeconomic status (SES). We concentrated on parental maltreatment (abuse and neglect) and bullying in school as childhood adversity variables and on perceived happiness, life satisfaction, and self-rated health as adulthood subjective well-being measures. Our empirical analysis was based on micro data from a survey in municipalities in and around the Tokyo metropolitan area (N = 3,292). We obtained four key findings. First, the experience of childhood adversity had a substantial negative impact on adulthood subjective well-being. Second, social support and SES significantly mediated the impact of childhood adversity. Third, a large proportion of the impact of childhood interpersonal adversity was unexplained by social support and SES mediation effects. Fourth, no social support or SES variable moderated the impact of childhood interpersonal adversity. Hence, we can conclude that childhood interpersonal adversity affects adulthood subjective well-being in a relatively independent manner rather than being substantially mediated or moderated by social support or SES. Accordingly, social policies should aim at reducing incidents of childhood maltreatment and bullying in addition to helping people enhance levels of social support and SES in later life.Childhood adversity, adulthood subjective well-being, mediation analysis, Japan

Mediating effects of social support and socioeconomic status on the association between childhood interpersonal adversity and adulthood mental health in Japan

In this study, we examined how the impact of child adversity on adulthood mental health is mediated by perceived social support and socioeconomic status (SES) in Japan, using micro data collected from surveys conducted in four municipalities in the Tokyo metropolitan area (N = 3,305). We focused on the self-reported experience of parental maltreatment and bullying in school. Our moderation analysis revealed that perceived social support and SES mediated 9-21% and 6-13%, respectively, of the impact of child adversity on selected mental health variables. The results highlight the mediating roles of social support and SES on the impact of adverse events in childhood on adulthood mental health. However, a large proportion of the impact is unexplained by either social support or SES, underscoring the need for reducing risks of parental maltreatment and bullying in school.Child adversity, Social support, Socioeconomic status, Adulthood mental health, Mediation analysis, Japan

The mediating effects of adulthood socioeconomic status and social support on adulthood impacts of childhood poverty in Japan

Previous studies have provided evidence of the lasting impact of low socioeconomic status (SES) in childhood on adulthood health. However, the mediating pathway that links them is still under debate. In this study, we examine how educational attainment, household income, and social support mediate the impact of low SES in childhood on self-rated health and health-risk behaviors in adulthood on the basis of micro data collected from a survey in municipalities in and around the Tokyo metropolitan area in Japan (N = 3,265). As a comprehensive measure for childhood SES, we utilized a binary variable of childhood poverty constructed from the retrospective assessment of the living standard at the age of 15. We estimated recursive bivariate probit models that consisted of (1) the main equation to predict adulthood health outcome by childhood poverty and other variables and (2) the auxiliary equation to predict childhood poverty by parental SES. This method allowed us both to capture a wide dimension of childhood SES and to mitigate the potential recall bias to the retrospective assessment of the past living standard. We observed that educational attainment, household income, and social support, when combined, mediated 35-55 percent of the impact of childhood poverty on adulthood SRH and health-risk behaviors, confirming the substantial magnitude of mediation. However, a large proportion of the impact was unexplained by these mediating effects, underscoring the importance of social policies aimed at reducing risks of childhood poverty.Childhood poverty, Self-rated health, health-risk behaviors, bivariate probit models, mediating effects

強磁性絶縁体におけるコヒーレント磁性物性の研究

Tohoku University藤原航三課

Melnikov Integral Formula for Beam Sea Roll Motion Utilizing a Non-Hamiltonian Exact Heteroclinic Orbit (Part II)

In the research filed of nonlinear dynamical system theory it is well known that a homoclinic/heteroclinic point leads to unpredictable motions, such as chaos. Melnikov’s method enables us to judge whether the system has a homoclinic/heteroclinic orbit. Therefore, in order to assess a vessels safety against capsizing, Melnikov’s method has been applied for the investigations of chaos that appears in beam sea rolling. This is because chaos is closely related to capsizing incidents. In a previous paper 1), the formula to predict the capsizing boundary by applying Melnikov’s method to analytically obtain the non-Hamiltonian heteroclinic orbit, was proposed. However, in that paper, limited numerical investigation had been carried out. Therefore further comparative research between the analytical and numerical results is conducted, with the result being that the formula is validated

Melnikov integral formula for beam sea roll motion utilizing a non-Hamiltonian exact heteroclinic orbit

Chaos appearing in a ship roll equation in beam seas, known as the escape equation, has been intensively investigated so far because it is closely related to capsizing accident. In particular, many applications of Melnikov integral formula have been reported in the existing literature. However, in all the analytical works concerning with the escape equation, Melnikov integral is formulated utilizing a separatrix for Hamiltonian part or a numerically obtained heteroclinic orbit for non-Hamiltonian part, of the original escape equation. To overcome such limitations, this paper attempts to utilise an analytical expression of the non-Hamiltonian part. As a result, an analytical procedure making use of a heteroclinic orbit of non-Hamiltonian part within the framework of Melnikov integral formula is provided

Analytical methods to predict the surf-riding threshold and the wave-blocking threshold

For the safe design and operation of high-speed craft it is important to predict their behaviour in waves. There still exists a concern, however, in the framework of the International Maritime Organization (IMO) with regards to the stability criteria. In particular, for high-speed craft, the higher limit of operational speed resulting in wave blocking as well as the lower limit known as the surf-riding threshold are important features. Therefore, by applying the polynomial approximation to wave induced surge force including the nonlinear surge equation, an analytical formula in order to predict the wave blocking and surf-riding thresholds is proposed. Comparative results of the surf-riding threshold and wave blocking threshold utilizing the proposed formula and the numerical bifurcation analysis indicate fairly good agreement. In addition, previously proposed analytical formulae are inclusively examined. It is concluded that the analytical formulae based on a continuous piecewise linear approximation and Melnikov’s method agrees well with the wave blocking threshold and the surf-riding threshold obtained by the numerical bifurcation analysis and the free-running model experiment. As a result, it is considered that these two calculation methods could be recommended for the early design stage tool for avoiding broaching and bow-diving

Analytical methods to predict the surf-riding threshold and the wave-blocking threshold

For the safe design and operation of high-speed craft it is important to predict their behaviour in waves. There still exists a concern, however, in the framework of the International Maritime Organization (IMO) with regards to the stability criteria. In particular, for high-speed craft, the higher limit of operational speed resulting in wave blocking as well as the lower limit known as the surf-riding threshold are important features. Therefore, by applying the polynomial approximation to wave induced surge force including the nonlinear surge equation, an analytical formula in order to predict the wave blocking and surf-riding thresholds is proposed. Comparative results of the surf-riding threshold and wave blocking threshold utilizing the proposed formula and the numerical bifurcation analysis indicate fairly good agreement. In addition, previously proposed analytical formulae are inclusively examined. It is concluded that the analytical formulae based on a continuous piecewise linear approximation and Melnikov’s method agrees well with the wave blocking threshold and the surf-riding threshold obtained by the numerical bifurcation analysis and the free-running model experiment. As a result, it is considered that these two calculation methods could be recommended for the early design stage tool for avoiding broaching and bow-diving

Psychometric properties of the Japanese version of the Recovery Attitudes Questionnaire (RAQ) among mental health providers: a questionnaire survey

The Japanese version of the 7-item Recovery Attitudes Questionnaire (RAQ). (DOCX 31 kb

Nonlinear dynamics of ship capsizing at sea

Capsizing is one of the worst scenarios in oceangoing vessels. It could lead to a high number of fatalities. A considerable number of studies have been conducted until the 1980s, and one of the discoveries is the weather criterion established by the International Maritime Organization (IMO). In the past, one of the biggest difficulties in revealing the behavior of ship-roll motion was the nonlinearity of the governing equation. On the other hand, after the mid-1980s, the complexity of the capsizing problem was uncovered with the aid of computers. In this study, we present the theoretical backgrounds of the capsizing problem from the viewpoint of nonlinear dynamics. Then, we discuss the theoretical conditions and mechanisms of the bifurcations of periodic solutions and numerical attempts for the bifurcations and capsizing