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Over a period of 4 years (1997–2000), British Columbia (BC) experienced tremendous growth in the illicit production and distribution
of domestically grown marijuana. By the close of 2000, each policing jurisdiction in BC had adopted a particular policy in
response to grow operation proliferation. In summary, four policy responses were noted. First, some maintained the status
quo wherein enforcement of police initiated investigations and citizens’ tips continued, but with no additional resources
specifically dedicated to grow operations. Second, some jurisdictions suspended the majority of investigation and enforcement
of grow operations. Third, some agencies implemented or reinforced existing resource intensive drug squads, which focused
on trafficking, sales and production of all types of drugs. Finally, some of the jurisdictions formed specialized tactical
units known as “green teams” that focused solely on the enforcement of marijuana production. In this paper, we evaluate the
effectiveness of green teams using a Geographic Information System (GIS) and difference-in-difference estimates. The results
indicate that green teams decrease grow operations within their target area without significant displacement to surrounding
areas.
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George E. TitaEmail: |
179.
Worley CG Wiltshire SS Miller TC Havrilla GJ Majidi V 《Journal of forensic sciences》2006,51(1):57-63
Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods. 相似文献
180.
This paper presents an uncomplicated and minimally invasive method for age-at-death determination in a contemporary Dutch (West European) population, by modifying the approach of assessment based on the age-related remodeling of bone tissue. In contrast to the usual "osteon count," a "non-remodeled tissue count" is undertaken. To optimize the method, proper zeroing of the polarization filter set of the microscope is essential. Instructions for setting the filters are given. A sample of femoral shaft segments totaling 162 individuals with ages ranging from 15 to 96 years is analyzed. Subperiosteal quantitative assessments are recorded at the most anterior point of the femoral shaft and also at points 25 degrees to the left and to the right of that point. Interobserver agreement in the assessments shows an acceptable degree of correlation. Bone remodeling with age does not progress in a linear, but in a curvilinear manner. Dependence of predicted age on nonremodeled surface counts in the analyzed areas of the anterior cortex of the femur appears to be significant. A set of regression equations is given. Sex can be ignored in age prediction. The small but statistically significant dependence of predicted age on cadaver length corresponds with the present strong secular increase in stature in the Netherlands. A concise catalogue with micrograph examples for every 10-year period in life is available upon request. 相似文献