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Volume Contents
Contents of Volume 19 (2000) 相似文献83.
The public choice literature contains little formal analysis of the bureaucratic choice of production modes — public or private — of publicly funded services. An important question to be addressed is why some governmental bodies choose to provide a publicly funded service with publicly owned and operated production units whereas other governmental bodies contract with private firms to provide the same publicly funded service. This paper is the first formal attempt to remedy this gap in the literature. We develop a theoretical explanation of the government decision maker's choice between public and private production modes based on utility maximizing behavior. We then examine empirically this choice employing logit analysis. The empirical results, which include several tests for robustness, confirm our theoretical explanation. The results are significant and suggest that non-monetary constraints are an important factor affecting this choice of production modes and that monetary constraints are less influential. 相似文献
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Latkoczy C Becker S Dücking M Günther D Hoogewerff JA Almirall JR Buscaglia J Dobney A Koons RD Montero S van der Peijl GJ Stoecklein WR Trejos T Watling JR Zdanowicz VS 《Journal of forensic sciences》2005,50(6):1327-1341
Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes. 相似文献
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An HPLC-APCI-MS(/MS) method for the (trace) analysis of the most commonly encountered peroxide explosives, hexamethylenetriperoxidediamine (HMTD) and triacetonetriperoxide (TATP), has been developed. With this method, HMTD and TATP have been analyzed in the same run. (Pseudo-)molecular ions of these peroxides have been obtained as base peak under the same condition. A series of product ions was produced from these pseudo-molecular ions ([HMTD - 1]+ and [TATP + NH4]+) in the MS/MS analysis. We also pioneered in showing that a TATP molecular ion [TATP + H]+ can be observed with HPLC-MS/MS. The limit of detection for HMTD and TATP was 0.26 and 3.3 ng, respectively, on column by HPLC-MS in the Full Scan mode and 0.08 and 0.8, respectively, by HPLC-APCI-MS/MS in Selected Reaction Monitoring (single mass unit) mode. The method presented has been applied successfully for the identification of peroxides in the bulk solid state (powder sample), as well as in post-blast extracts originating from a forensic case. For the post-blast extracts, the use of tandem MS has been shown clearly to be of crucial importance for the identification and detection of the peroxide explosives. 相似文献
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Kalunta-Crumpton A 《International journal of offender therapy and comparative criminology》2003,47(6):677-697
The primary aim of this article is to look at the impact of drugs on the drug-using Black population, and in doing so, the article draws comparative attention to drug use within the White community. The article is based on a research study of problem drug users registered with a London drugs project in 2000 and 2001. During the period of fieldwork, the vast majority of clients of the drug project were male, and the gap in the sex composition of the clients was more conspicuous in the Black group. For the sake of clarity in the use of statistical information, the article draws substance solely from information on the Black and White male clients. The findings present the Black community as a group who is also victimised by drugs but whose experiences of drug victimisation have often been undermined in the "war on drugs" rhetoric about drug trafficking. 相似文献