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71.
An increasing body of evidence now suggests the involvement of mitochondrial abnormalities in the etiology of neurodegenerative diseases, such as Parkinson's disease (PD) and Alzheimer disease. In this Perspective, we describe a recent study that shows that treatment of human patients with the antioxidant coenzyme Q(10'), which functions in concert with certain mitochondrial enzymes, reduced the worsening of symptoms associated with PD. These findings are consistent with the hypothesis that mitochondrial dysfunction plays a role in the pathogenesis of PD and that treatments that target mitochondrial biochemistry might ameliorate the functional decline observed in patients suffering from PD.  相似文献   
72.
The Comprehensive Everglades Restoration Plan, enacted in 2000, is a $7.8 billion federal/state investment in restoring the Florida Everglades ecosystem. The plan is a negotiated compromise between divergent interests in south Florida and promises to provide water and flood control for urban and agricultural users while maintaining a priority commitment to the natural system when allocating water produced by the 30-year project. The environmental community calls for independent scientific review of un-tested technologies, early and substantial hydrologic benefits to the remaining Everglades, including Everglades National Park, and strong programmatic regulations of the federal project to ensure that ecological restoration remains its primary purpose in spite of inherently conflicting interests at the state and local level.  相似文献   
73.
The use of 3,4-methylenedioxymethamphetamine (MDMA or "ecstasy") appears to be increasing worldwide, with "rave" attendees being one high-risk population. To date, however, only one study has collected ecstasy use information from rave attendees in the United States. To address this limitation, we collected self-report drug use information from 70 adult "club rave" attendees within the Baltimore-Washington corridor in April and May 2002. Data collection was scheduled between 12 A.M. and 5 A.M. Participation rates were high, with 85 percent of the club rave attendees completing the interview. Eighty-six percent of the respondents reported lifetime ecstasy use, 51 percent reported 30-day use, and 30 percent reported using ecstasy within the two days preceding the interview. While past-year ecstasy users were comparable to non-users with respect to a host of demographic and drug use variables, non-ecstasy users were significantly more likely than past-year users to perceive risks associated with the regular use of alcohol and ecstasy. Not surprisingly, non-ecstasy users were significantly more likely than past-year users to perceive harmful long-term physical and psychological effects associated with ecstasy ingestion. These findings suggest that rave attendees may be an important population for ecstasy-related prevention efforts.  相似文献   
74.
In the current study, we used a qualitative approach to investigate relevant beliefs and norms associated with codeine and promethazine hydrochloride cough syrup (CPHCS) consumption, initiation, and perceived addiction among 48 alternative school students who identified themselves as current CPHCS users. In general, both boys and girls believed that CPHCS addiction started during an individual's initial consumption. A majority of both groups reported that their second CPHCS event was initiated during the same or next day after their first event. Our findings suggest that friends and an innovative form of hip-hop music called "screw" are strong reinforcers of CPHCS use.  相似文献   
75.
76.
Correspondence to Dr Roger Manktelow, School of Social and Community Sciences, University of Ulster Magee College, Derry, BT48 7JL, Northern Ireland. Summary This article reports on the first extensive survey of ApprovedSocial Worker (ASW) activity under the Mental Health (NorthernIreland) Order 1986. The integrated health and social servicesorganizational structure, the adverse effects on individualmental health of the legacy of thirty years of civil conflictand the move from hospital to community care are significantfeatures which have influenced the delivery of mental healthsocial work services locally. The practice and experience ofASWs was surveyed by postal questionnaire and user and carerexperience of compulsory hospital admission was investigatedby a series of focus groups. The study revealed that two-thirdsof ASWs had experience of acting as an applicant in compulsoryhospital admission during the past two years. Nearly half (42per cent) of these ASWs had reported experience of between oneand five admissions and one-tenth had completed over twentyadmissions in the two-year period. In only a small minorityof cases did joint face-to-face assessment with the GeneralPractitioner (doctor) take place; nearly half of ASWs reporteddifficulties in obtaining transport; and only one-fifth of ASWshad experience of acting as a second approved social worker.Half of ASWs reported experience of guardianship, either asapplicant or in making the recommendation. Both service usersand carers reported a lack of understanding about the role ofthe ASW and complained about the lack of alternative resourcesthat ASWs could use to prevent hospital admissions. These findingsare discussed and a number of recommendations are proposed forimprovements to approved social worker practice.  相似文献   
77.
We consider the piecewise proportional hazards (PWPH) model with interval-censored (IC) relapse times under the distribution-free set-up. The partial likelihood approach is not applicable for IC data, and the generalized likelihood approach has not been studied in the literature. It turns out that under the PWPH model with IC data, the semi-parametric MLE (SMLE) of the covariate effect under the standard generalized likelihood may not be unique and may not be consistent. In fact, the parameter under the PWPH model with IC data is not identifiable unless the identifiability assumption is imposed. We propose a modification to the likelihood function so that its SMLE is unique. Under the identifiability assumption, our simulation study suggests that the SMLE is consistent. We apply the method to our cancer relapse time data and conclude that the bone marrow micrometastasis does not have a significant prognostic factor.  相似文献   
78.
This study challenges the prevailing view that marital companionship promotes marital satisfaction. By following a cohort of married couples for over a decade and by incorporating several methodological improvements—such as refining the measurement of marital satisfaction, determining how much spouses enjoy doing the leisure activities they pursue together and apart, and using diary data to portray marital leisure patterns—we found that the association between companionship and satisfaction is less robust than previously believed, and that it depends on how often spouses pursue activities that reflect their own and their partner's leisure preferences. Over time, involvement in leisure liked by husbands but disliked by wives, whether as a couple or by husbands alone, is both a cause and a consequence of wives' dissatisfaction.  相似文献   
79.
Sentiments     
This paper develops a new theory of fluctuations—one that helps accommodate the notions of “animal spirits” and “market sentiment” in unique‐equilibrium, rational‐expectations, macroeconomic models. To this goal, we limit the communication that is embedded in a neoclassical economy by allowing trading to be random and decentralized. We then show that the business cycle may be driven by a certain type of extrinsic shocks which we call sentiments. These shocks formalize shifts in expectations of economic activity without shifts in the underlying preferences and technologies; they are akin to sunspots, but operate in unique‐equilibrium models. We further show how communication may help propagate these shocks in a way that resembles the spread of fads and rumors and that gives rise to boom‐and‐bust phenomena. We finally illustrate the quantitative potential of our insights within a variant of the RBC model.  相似文献   
80.
Abstract

We review the literature on nonstandard work with three aims: to portray the breadth and nature of the research and theorizing to date, to document the challenges and opportunities this domain poses to both practice and theory, and to bring the study of nonstandard work more to the center stage of micro-OB. After defining nonstandard work and documenting scholarly interest in it, we discuss the literature on the experience of nonstandard workers, on managing the nonstandard workforce, as well as that on managing the interface between standard and nonstandard workers. We analyze the themes that are raised in these literatures and point to new research questions that need to be addressed. Research on nonstandard work can enhance our understanding of the nature of work, the relationship between individuals and organizations, and how organizations and individuals can undertake these new work forms.  相似文献   
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