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271.
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition.  相似文献   
272.
Child death due to repeated episodes of physical assault or neglect has been termed the child abuse-maltreatment syndrome (CAMS). We characterized the injuries in a series of fatally abused or maltreated child to delineate objective diagnostic criteria for the CAMS for use by clinicians and pathologists. All deaths (age <17 years) investigated by the Office of the Chief Coroner for Ontario, Canada during the time period 1990-1995 were reviewed. Cases of CAMS were defined as death due to lethal recent injury or malnutrition in the presence of significant old (healing or healed) injuries indicative of repeated episode of inflicted trauma. The nature and frequency of the various injuries was determined. The frequency of the shaken baby syndrome, and the types and frequency of ano-genital injuries were also studied. Twenty-one cases of fatal CAMS were found in the study period. Most cases had significant recent head injury with intra-cranial hemorrhage (71%). Other significant recent injuries commonly observed included blunt injuries of the skin and soft tissues (67%), blunt abdominal trauma with visceral injuries (14%), and fractures (18%). Eight cases (38%) fulfilled accepted criteria for the shaken baby syndrome. Many children with fatal head injuries had evidence of older head trauma (38% of all cases). A significant minority of cases had evidence of malnutrition due to neglect (10%) or ongoing ano-genital injuries (10%). Most cases of child homicides due to repeated episodes of abuse or maltreatment involve head trauma including shaken baby syndrome. Fractures of long bone and ribs, the classical markers of child abuse, were relatively infrequent compared with head injury. A proportion of cases had ano-genital injuries due to repeated sexual abuse or punitive maltreatment. All clinicians and pathologists must recognize the wide spectrum of injuries in child abuse to ultimate protect the victim or other children in an at-risk situation.  相似文献   
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Government's response to Hurricane Katrina: A public choice analysis   总被引:1,自引:0,他引:1  
We use public choice theory to explain the failure of FEMA and other governmental agencies to carry out effective disaster relief in the wake of Hurricane Katrina. The areas in which we focus are: (1) the tragedy of the anti-commons resulting from layered bureaucracy, (2) a type-two error policy bias causing over cautiousness in decision making, (3) the political manipulation of disaster declarations and relief aid to win votes, (4) the problem of acquiring timely and accurate preference revelations, (5) glory seeking by government officials, and (6) the shortsightedness effect causing a bias in governmental decision making.  相似文献   
276.
Organizing the War on Terrorism   总被引:4,自引:2,他引:4  
The network of public agencies, private firms, nonprofit organizations, ad hoc groups, and individual volunteers that deals with natural and technological hazards and disasters did a remarkable job of responding to and helping us recover from the September 11th attacks. That national emergency management network, along with the national security and law enforcement networks, provides a foundation for our war on terrorism, helps us mitigate the hazard of terrorism, and improves our preparedness for future violence. However, coordinating the efforts of the networks will be a real challenge for the director of homeland security and his or her state and local counterparts. Coordination will necessitate using legal authority to assure compliance, economic and other incentives to encourage compliance, formal partnerships to encourage collaboration, informal understandings to encourage cooperation, and personal encouragement to influence appropriate action. A top–down, command–and–control approach to the war on terrorism, such as the proposed Department of Homeland Security is intended to provide, may be counterproductive.  相似文献   
277.
Relationship schemas are core elements of personality that guide interpersonal functioning. The aim of this study is to examine stability and change in relationship schemas across two developmental epochs—adolescence and young adulthood—in the stories that people tell about their interactions with others. Using the Core Conflictual Relationship Theme Method, relationship themes were coded from semistructured interviews conducted in adolescence and again at age 25. The sample consisted of 40 participants in a longitudinal study of adolescent and young adult psychological development. There was considerable stability in the frequency with which particular themes were expressed in the narratives of adolescents and young adults. Significant changes from adolescence to young adulthood included a decrease in the perception of others as rejecting and of the self as opposing others. Young adults saw themselves and others more positively, and used a broader repertoire of themes in their relationship narratives than they had as adolescents. The basic continuity and particular changes in relationship schemas found in this study are consistent with knowledge about the adolescent-to-young-adult transition derived from other empirical and clinical findings. Relationship schemas may be rich units of study for learning about the development of interpersonal functioning.  相似文献   
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Models of legislative organization frequently begin with the premise that the committee system serves the re-election interests of incumbent legislators. Attempts to substantiate this notion empirically have been unsuccessful. Nevertheless, the notion lives on, nourished by a stylized characterization of the committee system. In the standard model committees have jurisdictional monopolies over specialized policy areas and legislators gravitate toward those committees that deal most closely with the policy concerns of their constituents. Contrary to this simplifying characterization, the degree of monopoly control and policy specialization varies across standing committees in the us congress. Some committees have wide jurisdictions and attract members with diverse policy preferences. Jurisdictional overlap and resulting turf battles are common aspects of congressional sessions. We suggest here that these realities warrant a re-opening of the empirical investigation into the link between electoral success and committee characteristics. Our findings indicate that assignment to a committee with a relatively high degree of monopoly control increases a member's vote share, and that assignment to a narrowly focused (specialized) committee does not.  相似文献   
280.
Although there have been several studies of women in legislatures in Canada, a cabinet position is a much stronger position from which to wield power in an executive-centered and party-disciplined parliamentary system. In the past decade, the increase of women's share of legislative seats, for majority parties as well as others, has led to more women being appointed to cabinet portfolios. This article utilizes data from the ten Canadian provinces over an 18-year period, from 1976 to 1994, to assess patterns of such appointments by province, party, percentage of women in the governing party, and percentage of women in the legislature. The proportion of women in the governing party far outweighs other variables in its impact on the percentage of women in the cabinet, in contrast to a previous study of West European cabinets which found that more women in the legislature was of greater importance. Although a high level of multicollinearity indicates caution in attempting to distinguish between the impact of these two variables, the differences in these studies may be due to Canadian provinces having single-party majority governments while West European cabinets are often coalitions.  相似文献   
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