Dementia is divided roughly into cerebrovascular dementia and Alzheimer's disease. The former is a cerebral infarction blocked by many arteriosclerosis in relatively small blood vessel,and the later is a disease which brain tissue is destroyed by many amyloid β protein (Aβ). The onset mechanism of both diseases is connected with reactive oxygen species. Cerebrovascular dementia is arteriosclerosis connecting with oxidation of LDL by reactive oxygen species. The other hand,Alzheimer's disease is caused via destruction of brain tissue by reactive oxygen species produced from the complex-compound with Aβ and trace metal such as Fe,Cu and Zn. This mechanism is important to the strategy for development of therapeutic drugs,and to the primary prevention by improvement of life-style. Dementia may be a life-style related disease.

　As a life-style which easily become dementia, excess intake of energy is pointed out. Especially, excess intake of animal fat and alcohol is risky. Intake-deficiency of vegetables and fruits containing many antioxidants,vitamin and minerals,and fish containing n-3 fatty acids are serious. Furthermore, smoking and less physical exercise and social communication are important risk factors.

　In this review,I introduce the reasons why life-style and reactive oxygen species are causes of dementia, and the way how to do for the primary prevention of dementia.

[Purpose] To examine cross-cultural stress factors and mental well-being of foreign residents in Japan in relation to personality traits and stress coping strategies.

[Design] A descriptive and correlational study using quantitative methods based on Lazarus's stress theory. [Method] 638 questionnaires were distributed to foreign residents at randomly selected Japanese universities. 143 questionnaires were analyzed using descriptive analyses.

[Findings] For the foreign residents studied here there seem to be clear correlations between gender, stress, personality, coping strategies and mental health. Those most at risk are: woman; Type A; sensitive to emotion-related stress factors; likely to adopt emotion-focused stress coping strategies. Many variables are involved, but Key factors may be identified which point to foreign residents who run a high risk of mental health problems. Women are more at risk than men. Type A residents, both male and female, are more at risk than others. Emotion-related stressors (e.g. loneliness, homesickness, increased feelings of anxiety, disappointment with life in Japan) are risk factors. Finally, a tendency to emotion-focused coping strategies (negative strategies) suggests higher risk. Residents who display several of these risk factors may require careful monitoring.

　The aim of this study was to illustrate the status and factors affecting community participation by mentally disabled persons suffering from schizophrenia in community workshops and its effect on their QOL.

　Among the three types of activities, income-generating activities accounted for the most participants. For an allied factor, satisfaction with daily life, statistical significance was found for community participation integrating the three types of activities and income-generating activities. As predisposing factors, in the SECL score, community participation integrating the three types of activities, income-generating activities and volunteer activities were statistically significant.

　A link was observed between the participation in community activities and the satisfaction of community workshop attendees with daily life in QOL categories, suggesting that community participation has a possible influence on their satisfaction with daily life. Since community participation hinges on the degree of self-efficacy, confidence in their community life needs to be bolstered.