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111.
112.
The analysis of gamma-hydroxybutyric acid (GHB) is problematic because it is hygroscopic, it lacks a good UV chromophore, and it undergoes heat-induced cyclization. This paper presents a new method utilizing ion-exchange chromatography (IC) with conductivity detection. The simple sample preparation, rapid analysis time, and inorganic anion detection capabilities are all advantages over the current methods. The detection of inorganic salts (formed during GHB synthesis) gives insight into the synthetic route utilized and can aid in drug seizure comparison. The developed method has a detection limit for GHB anions of 0.57 mg/L and chloride of 0.22 mg/L. A comparison of this technique with a current gas chromatography-mass spectrometry technique is presented, and a t-test found that the two methods' results are not statistically different at the 99.9% confidence level demonstrating the merits of this fast, simple, and informative IC method as a routine screening tool.  相似文献   
113.
This column provides a country by country analysis of the latest legal developments, cases and issues relevant to the IT, media and telecommunications’ industries in key jurisdictions across the Asia Pacific region. The articles appearing in this column are intended to serve as ‘alerts’ and are not submitted as detailed analyses of cases or legal developments.  相似文献   
114.
This column provides a country by country analysis of the latest legal developments, cases and issues relevant to the IT, media and telecommunications’ industries in key jurisdictions across the Asia Pacific region. The articles appearing in this column are intended to serve as ‘alerts’ and are not submitted as detailed analyses of cases or legal developments.  相似文献   
115.
This column provides a country by country analysis of the latest legal developments, cases and issues relevant to the IT, media and telecommunications’ industries in key jurisdictions across the Asia-Pacific region. The articles appearing in this column are intended to serve as ‘alerts’ and are not submitted as detailed analyses of cases or legal developments.  相似文献   
116.
This column provides a country by country analysis of the latest legal developments, cases and issues relevant to the IT, media and telecommunications’ industries in key jurisdictions across the Asia-Pacific region. The articles appearing in this column are intended to serve as ‘alerts’ and are not submitted as detailed analyses of cases or legal developments.  相似文献   
117.
Previous work suggests that δ(18)O values of human hair can be used to constrain the region-of-origin of unknown individuals, but robust assessments of uncertainties in this method are lacking. Here we assess one source of uncertainty - temporal variation in the δ(18)O value of drinking water - using a monthly tap water survey of δ(18)O to develop geospatial models (i.e., maps) of the intra-annual variation (seasonality) in tap water δ(18)O for the contiguous USA. Temporal variation in tap water δ(18)O was correlated with water-supply type, and was related to geographic patterns of precipitation δ(18)O seasonality and water residence time. The maps were applied in a Bayesian framework to identify the geographic origin of an unidentified woman found in Utah, based on measured δ(18)O of scalp hair. The results are robust in specifying parts of the western USA as the most likely region-of-origin. Incorporation of tap water δ(18)O seasonality in the analysis reduces the precision of geographic assignments, but other sources of uncertainty (e.g., spatial interpolation uncertainty) have an equal or larger effect.  相似文献   
118.
We present a test of the crime-deterrent effect of police-monitored street-viewing CCTV cameras using viewsheds of areas that were visible by cameras via direct line-of-sight and that were digitized using easily replicable methods, Google Maps, and standard GIS tools. A quasi-experimental research design, using camera installation sites and randomly selected control sites, assessed the impact of CCTV on the crimes of shootings, auto thefts, and thefts from autos in Newark, NJ, for 13 months before and after camera installation dates. Strategically-placed cameras were not any different from randomly-placed cameras at deterring crime within their viewsheds; there were statistically significant reductions in auto thefts within viewsheds after camera installations; there were significant improvements to location quotient values for shootings and auto thefts after camera installations. There was no significant displacement and there was a small diffusion of benefits, which was greater for auto thefts than shootings. The system of cameras in Newark is not as efficient as it could be at deterring certain street crimes; some camera locations are significantly more effective than others. Results of a system-wide evaluation of CCTV cameras should not be the only basis for endorsing or contesting the use of CCTV cameras for crime control or prevention within a city. Future research should test whether the effectiveness of CCTV cameras are dependent upon the micro-level attributes of environments within which they are installed.  相似文献   
119.
How do economic freedom and culture impact economic growth? This paper argues that culture, as measured by the World Values Surveys, and economic institutions associated with economic freedom are both independently important for economic prosperity, but the strength of their impact can be better understood only when both are included in the growth regression. Our results indicate that economic freedom is more important than culture for growth outcomes, suggesting substitutability between the two. We posit that culture is important for growth when economic freedom is absent, diminishing in significance once economic freedom is established.  相似文献   
120.
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