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91.
Rational choice models are increasingly used in explanations of voting and elections. Their adoption is often urged, rather uncritically, on the grounds that they provide a unified and exact explanation across political science. Far from doing so, however, their definitions of ‘rationality’ may differ radically even within a limited area, such as party and voting behaviour. Shifts of meaning from one model to another may be obscured by mathematical formalism, which concentrates attention on the derivation of conclusions from basic assumptions, rather than on the practical relevance of their relationship to the assumptions behind other models. A mathematical formulation may not, however, be the most relevant for purposes of electoral explanation. Rigorous verbal formulations can represent electors' and politicians' decision procedures more realistically, while remaining generally accessible and supporting detailed inter-comparisons of their working assumptions. Through these, rational choice explanations can be brought closer together and decisions between them made with a clear knowledge of what is involved, thus providing a better basis for cumulative research. The process of theoretical evaluation and assimilation is illustrated here with two original theories of voting and party competition.  相似文献   
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This paper begins by examining the arguments that led to the change of emphasis from residential training and detention to community-based measures in Hong Kong. Police cautioning and community support services are introduced. An evaluation of the services provided found that the majority of respondents reported high levels of satisfaction with them. It is likely that the services exerted positive influences on the respondents’ deviant behaviour, family values and sense of social responsibility, but one-fifth of them continued to commit deviant acts. Parents’ participation was not high. Young offenders rarely took responsibility for the offence they committed or understood the harm they had done to victims, and victims were not involved in deciding the intervention plan. The conclusions raise issues about the future for Hong Kong. They consider new diversionary strategies for responding to young people and debate the values that should underpin them.
T. Wing LoEmail: Phone: +852-2-7888986Fax: +852-2-7888960
  相似文献   
94.
The Scent Transfer Unit (STU-100) is a portable vacuum that uses airflow through a sterile gauze pad to capture a volatiles profile over evidentiary items for subsequent canine presentation to assist law enforcement personnel. This device was evaluated to determine its ability to trap and release organic compounds at ambient temperature under controlled laboratory conditions. Gas chromatography-mass spectrometry (GC-MS) analyses using a five-component volatiles mixture in methanol injected directly into a capture pad indicated that compound release could be detected initially and 3 days after the time of collection. Additionally, 15 compounds of a 39-component toxic organic gaseous mixture (10-1000 parts per billion by volume [p.p.b.(v)]) were trapped, released, and detected in the headspace of a volatiles capture pad after being exposed to this mixture using the STU-100 with analysis via GC-MS. Component release efficiencies at ambient temperature varied with the analyte; however, typical values of c. 10% were obtained. Desorption at elevated temperatures of reported human odor/scent chemicals and colognes trapped by the STU-100 pads was measured and indicated that the STU-100 has a significant trapping efficiency at ambient temperature. Multivariate statistical analysis of subsequent mass spectral patterns was also performed.  相似文献   
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A method was developed for simultaneously analyzing cocaine (COC), benzoylecgonine (BZE), norbenzoylecgonine (BNE), norcocaine (NCOC), ecgonine (ECG), ecgonine methyl ester (EME), m-hydroxybenzoylecgonine (HBZE), anhydroecgonine methyl ester (AEME), cocaethylene (CE), norcocaethylene (NCE), and ecgonine ethyl ester (EEE) in blood, urine, and muscle. Available deuterated analogs of these analytes were used as internal standards. Proteins from blood and muscle homogenate were precipitated with cold acetonitrile. After the removal of acetonitrile by evaporation, the supernatants and urine were subjected to solid-phase extraction. The eluted analytes were converted to their hydrochloride salts and derivatized with pentafluoropropionic anhydride and 2,2,3,3,3-pentafluoro-1-propanol. The derivatized products were analyzed by a gas chromatograph (GC)/mass spectrometer by selected ion monitoring. The limit of detection (LOD) for COC, BZE, NCOC, EME, CE, NCE, and EEE was 2ng/ml, while the LODs for BNE, ECG, HBZE, and AEME were 25, 640, 50, and 13 ng/ml, respectively. This method was successfully applied in analyzing 13 case samples from aviation accident pilot fatalities and motor vehicle operators. AEME concentrations found in the 13 samples were consistent with those produced solely by the GC inlet pyrolysis of COC controls in blood. Anhydroecgonine cannot be used as a marker for the abuse of COC by smoking because it is also pyrolytically produced from COC metabolites on the GC inlet. The developed method can be effectively adopted for analyzing COC and related compounds in urine, blood, and muscle by a single extraction with increased sensitivity through formation of hydrochloride salts and using a one-step derivatization.  相似文献   
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Dennis T. Avery 《Society》2007,44(6):137-143
High-yield farming—more agricultural output per acre of farmland—has been a boon to mankind and to nature. If today’s agricultural efficiency was the same as in the 1950s, the world would need three times the cropland to produce today’s food supply. That would mean that 15-16 million mi2 of forest would have been destroyed—all the global forest area available today. Rising population and increased affluence will require a tripling of agricultural efficiency in the next 50 years if we are to protect wildlife at the same time. More investment in agricultural research and education will be required, but this is what produced the previous green revolution.
Dennis T. AveryEmail:
  相似文献   
99.
Gordon Tullock is one of the founders of the field of public choice, of the Public Choice Society, and of the Public Choice Center. He is a coauthor with James M. Buchanan of one of the true classics in the public choice field—The Calculus of Consent. He has been one of the field’s most prolific scholars, with his research spanning virtually all dimensions of the public choice field. This article surveys his major contributions.  相似文献   
100.
Drug-facilitated sexual assault (DFSA) has been defined as the use of a chemical agent to facilitate a sexual assault. We report two cases of the use of tetrahydrozoline for DFSA. We believe this is the first report with urinary quantification of tetrahydrozoline levels postassault. Blood and urine were obtained c. 20 h postexposure in two cases of reported DFSA. Tetrahydrozoline was not detected in blood but was identified in urine in both victims. After initial identification in the urine using the 2010 update to the AAFS mass spectrometry database library, tetrahydrozoline was quantified at 114 and 150 ng/mL, respectively, using GC/MS. Two unique clinical features reported in these cases were intermittent periods of consciousness and postexposure vomiting. Use of GC/MS was successful in identifying tetrahydrozoline in the 100 ng/mL range up to 20 h postexposure. For victims with late presentation, urine may be a better sample for evaluation for tetrahydrozoline.  相似文献   
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