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961.
To determine sex and race differences in muscle power per unit of muscle contraction, knee-extensor muscle power normalized for knee-extensor muscle volume was measured in 79 middle-aged and older adults (30 men and 49 women, age range 50-85 years). Results revealed that women displayed a 38% faster peak movement velocity than men and African Americans had a 14% lower peak movement velocity than Whites of a similar age when expressed per unit of involved muscle (p < .001). As expected, men exhibited greater knee-extensor strength and peak power per unit of muscle than women, but women had a faster knee- extension movement velocity per unit of muscle than men at the same relative strength level. Moreover, African Americans had greater knee-extensor muscle volume than Whites but exhibited lower knee-extensor strength and lower movement velocity per unit of muscle when tested at the same relative strength levels.  相似文献   
962.
963.
Mutations in the DJ-1 gene are associated with rare forms of autosomal recessive early-onset Parkinson's disease (PD). Although the precise physiological function of DJ-1 remains obscure, accumulating evidence suggests that DJ-1 may normally function as a redox-sensitive molecular chaperone that can protect against the deleterious effects of oxidative stress, particularly in mitochondria. Recent studies in the fruit fly, Drosophila melanogaster, have shed further light on the biological role of DJ-1. DJ-1-deficient Drosophila models exhibit distinct phenotypes but collectively highlight a prominent neuroprotective role for DJ-1 against oxidative insult. However, Drosophila lacking DJ-1 do not consistently produce a useful PD-like phenotype (that is, they generally fail to exhibit degeneration of neurons that contain the neurotransmitter dopamine), which may reflect putative compensatory neuroprotective mechanisms. DJ-1-deficient fly models further highlight the utility of Drosophila as an important tool for elucidating protein function and for modeling neurodegenerative disease.  相似文献   
964.
Life style research has become an independent branch of social structure analysis, that systematically complements classical research on social inequality in the explanation of social action and of attitudes. However, there are important theoretical gaps in life style research: firstly, there is a lack of theoretical proposals to explain the statistical connection between life styles on the one hand and social action and attitudes on the other hand. Secondly, it remains unclear, why life styles sometimes are very good predictors of social action and at other times they are not. In a first step this article puts forward an action theoretic framework as foundation for life style research, that implies a conceptual shift from life styles to cultural preferences. In a second step I develop three theses, that state relatively precisely the conditions for a high or low explanatory power of cultural preferences. They are empirically tested in a secondary data analysis, that supports the applicability of the theoretical ideas developed in the paper.  相似文献   
965.
This case study examines the unique occurrence of two food contamination crises at Snow Brand Milk Products Co., Ltd., the top company in the Japanese milk product industry. The separate incidents of food poisoning occurred in 1955 and 2000; the latter incident, involving more than 10,000 victims, was the worst case of food poisoning in Japanese history.  相似文献   
966.
Fundamental within Singapore's modernisation push ‘From Third World to First’ was the long-term strategy of establishing a Singapore identity based on multiracialism, multilingualism, multiculturalism and multireligiousity (the ‘4Ms’). But while wholesale landscape changes have largely removed earlier associations between ethnicity and residence, government promotion of a shared Singapore identity has been frustrated by the lagging educational and socio-economic achievements of Singapore's Malay minority. Prior to the events of ‘9/11’ government concern had centred on the growing popularity of private Islamic schools, or madrasahs, which in the government's view could affect educational standards in the city-state. However, following the destruction of the World Trade Center government attention was quickly shifted to the promotion of ‘racial harmony’ and Singaporeans were urged to ‘get to know your neighbours’ in a tacit admission that 40 years of ‘racial’ assimilation had yet to produce ethnically integrated, cross-cultural community spirit. Subsequent events, particularly the arrest of local Jemaah Islamiyah operatives and the destruction in Iraq, have impacted most strongly upon Singapore's Malay-Muslim community and posed challenges to its identity within a multicultural society.  相似文献   
967.
968.
Using a sample consisting of 4,997 married couples from the National Survey of Families and Households, individual emotional distress, the occurrence of couple disagreements, couple fighting, and couple quality time together mediated the relationship between financial strain and personal assessments of marital instability. The overall results suggest that financial strain influences both positive and negative forms of couple interaction which are stronger mediators than personal emotional distress of the relationship between financial strain and marital instability. The results further suggest that there were no gender differences among these linkages.  相似文献   
969.
970.
Internet gambling is growing rapidly, as is concern about its possible effect on the public’s health. This paper reports the results of the first prospective longitudinal study of actual Internet sports gambling behavior during eight study months. Data include recorded fixed-odds bets on the outcome of sporting contests and live-action bets on the outcome of events within contests for 40,499 Internet sports gambling service subscribers who enrolled during February 2005. We tracked the following primary gambling behaviors: daily totals of the number of bets made, money bet, and money won. We transformed these variables into measures of gambling involvement. We analyzed behavior for both fixed-odds and live-action bets. The median betting behavior of the 39,719 fixed-odds bettors was to place 2.5 bets of €4 (approximately $5.3 US) every fourth day during the median 4 months from first to last bet. This typical pattern incurred a loss of 29% of the amount wagered. The median betting behavior of the 24,794 live-action bettors was to place 2.8 wagers of €4 every fourth day during the median duration of 6 weeks at a loss of 18% of the amount wagered. We also examined the behavior of empirically determined groups of heavily involved bettors whose activity exceeded that of 99% of the sample.  相似文献   
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