Urinary excretion profiles of 11-nor-9-carboxy-delta9-tetrahydrocannabinol and 11-hydroxy-delta9-THC: cannabinoid metabolites to creatinine ratio study IV

The objective of this study was to compare urinary excretion patterns of two cannabinoid metabolites in subjects with a history of chronic marijuana use. The first metabolite analyzed was nor-9-carboxy-delta9-tetrahydrocannabinol (delta9-THC-COOH), the major urinary cannabinoid metabolite that is pharmacologically inactive. The second metabolite 11-OH-delta9-THC is an active cannabinoid metabolite and is not routinely measured. Urine specimens were collected from four subjects on 12-20 occasions > or = 96 h apart in an uncontrolled clinical setting. Creatinine was analyzed in each urine specimen by the colorimetric modified Jaffé reaction on a SYVA 30R biochemical analyzer. All urine specimens analyzed for 11-OH-delta9-THC had screened positive for cannabinoids with the EMIT II Plus cannabinoids assay (cut-off 50 ng/mL) on a SYVA 30R analyzer and submitted for delta9-THC-COOH confirmation by GC-MS (cut-off concentration 15 ng/mL). Eleven-OH-delta9-THC was measured by GC-MS with a cut-off concentration of 3 ng/mL. Both GC-MS methods for cannabinoid metabolites used deuterated internal standards for quantitative analysis. The mean (range) of urinary delta9-THC-COOH concentration was 1153 ng/mL (78.7-2634) with a cut-off of 15 ng/mL. The mean (range) of delta9-THC-COOH/creatinine ratios (ng/mL delta9-THC-COOH/mmol/L creatinine) was 84.1 (8.1-122.1). The mean (range) urinary of 11-OH-delta9-THC concentration was 387.6 ng/mL (11.9-783) with a cut-off of 3 ng/mL, and the mean (range) of 11-OH-delta9-THC/creatinine ratio (ng/mL 11-OH-delta9-THC/mmol/L creatinine) was 29.7 (1.2-40.7). Of the 63 urine specimens submitted for delta9-THC-COOH confirmation by GC-MS, 59/63 urine specimens (94%) were positive for delta9 -THC-COOH and 51/63 (81%) were positive for 11-OH-delta9-THC. Overall, the concentrations of 11-OH-delta9-THC in urine specimens collected > or = 96 h apart were lower than delta9-THC-COOH concentrations in 50/51 of the urine specimens in this population. Further urinary cannabinoid excretion studies are needed to assess whether 11-OH-delta9-THC analyses have a role when assessing previous marijuana or hashish use in chronic users whose urine specimens remain positive for delta9-THC-COOH for an extended period of time after last drug use.     

Corporate Opportunities: The Appropriation by Company Officers of Business Opportunities Belonging to the Company

Netherlands International Law Review -     

Urinary excretion profiles of 11-nor-9-carboxy-Delta9-tetrahydrocannabinol: a Delta9-THC-COOH to creatinine ratio study #2

Subjects with a history of chronic marijuana use were screened for cannabinoids in urine specimens with the EMIT((R)) II Plus cannabinoids assay with a cut-off value of 50 ng/ml. All presumptively positive specimens were submitted for confirmatory analysis for the major urinary cannabinoid metabolite (Delta(9)-THC-COOH) by GC-MS with a cut-off value of 15 ng/ml. Creatinine was analyzed in each specimen as an index of dilution. Huestis and Cone [J. Anal. Toxicol. 22 (1998) 445] reported that serial monitoring of Delta(9)-THC-COOH to creatinine ratios in paired urine specimens collected at least 24h apart could differentiate new drug use from residual Delta(9)-THC-COOH excretion. The best accuracy (85.4%) for predicting new marijuana use was a Delta(9)-THC-COOH/creatinine ratio > or =0.5 (dividing the Delta(9)-THC-COOH to creatinine ratio of specimen 2 by the specimen 1 ratio). In a previous study in this laboratory [J. Anal. Toxicol. 23 (1999) 531], urine specimens were collected from chronic marijuana users at least 24h apart and dilute urine specimens (creatinine values <2.2 micromol/l) were excluded from the data analysis. The objective of the present study was to determine whether creatinine corrected urine specimens positive for cannabinoids could differentiate new marijuana use from the excretion of residual Delta(9)-THC-COOH in chronic users of marijuana based on the Huestis 0.5 ratio. Urine specimens (N=946) were collected from 37 individuals with at least 48h between collections. All urine specimens were included in the data review irrespective of creatinine concentration. The mean urinary Delta(9)-THC-COOH concentration was 302.4 ng/ml, mean Delta(9)-THC-COOH/creatinine ratio (ng/ml Delta(9)-THC-COOH/(mmol/l) creatinine) was 29.3 and the Huestis ratio calculation indicated new drug use in 83% of all sequentially paired urine specimens. The data were sub-divided into three groups (A-C) based on the mean Delta(9)-THC-COOH/creatinine values. Interindividual Delta(9)-THC-COOH/creatinine mean values ranged from 2.2 to 13.8 in group A (264 specimens, N=15 subjects) where 80.7% of paired specimens indicated new drug use. In group B, mean Delta(9)-THC-COOH/creatinine values ranged from 15.3 to 37.8 in 444 specimens (N=14 subjects) and 83.3% of paired specimens indicated new drug use. In group C, individual mean Delta(9)-THC-COOH/creatinine values were >40.1 (41.3-132.5) in 238 urine specimens (N=8 subjects) and 85.3% of paired urine specimens indicated new marijuana use. Correcting Delta(9)-THC-COOH excretion for urinary dilution and comparing Delta(9)-THC-COOH/creatinine concentration ratios of sequentially paired specimens (collected at least 48h apart) provided an objective indicator of new marijuana use in this population.     

Characterization of gunpowder samples using time-of-flight secondary ion mass spectrometry (TOF-SIMS)

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was utilized to obtain characteristic mass spectra from three different smokeless powders and six different black powder samples. In these mass spectra, peaks indicative of both the organic and inorganic additive constituents in the gunpowders were observed. TOF-SIMS was able to successfully differentiate between the different black and smokeless gunpowder samples analyzed with the aid of principal components analysis (PCA), a multivariate statistical analysis approach often used to reduce the dimensionality of complex data. TOF-SIMS was also used to obtain information about the spatial distribution of the various additives contained within the gunpowder samples. SIMS imaging demonstrated that that the samples could potentially be characterized by their 2-D structure, which varied from sample to sample. These results clearly demonstrate the feasibility of utilizing TOF-SIMS as a tool for the characterization and differentiation of gunpowder samples for general forensic applications.     

Gresham's law in politics: Why are politicians not the most remarkable men for probity and punctuality?

Economists have always criticized politicians' behaviour. Adam Smith called politicians “crafty and insidious"; and, more recently Brennan and Buchanan have applied Gresham's law to politics, arguing that the man for whom the expected profit is highest will be the highest bidder for political power. However in their model there is not an argument to explain why these people are elected to public offices. This paper presents a supply model and a demand model explaining why politicians behave as “wicked" men, and are elected by the citizens. Firstly, we develop a model of repetitive and reputation games that shows why probity is not important for many politicians. The second model employs asymmetric information theory to explain why voters elect “wicked" people even if probity is a highly estimated value for them. The paper ends with some suggestions of legal reforms for reducing this asymmetry of information. classification D72. D82     

Cooperative learning vs Confucian heritage culture's collectivism: confrontation to reveal some cultural conflicts and mismatch

Asian countries with Confucian heritage culture (CHC) such as China, Vietnam, Singapore, Korea and Japan have been proven to share characteristics of a collectivist society. Researchers agree that this collectivist mentality strongly supports cooperation that CHC's learners/workers best perform in groups. However, little is known about the other side of the coin. Whilst applying a method born in one culture to another, cultural differences have been forgotten. The so-called global application has led to a situation in which a Western model is forced to launch in a completely new and different context. This new context and the existing cultural values are not always incorporated into the implementation of a Western concept of cooperative learning. Consequently, it does not necessarily follow that all forms of cooperative learning will surely succeed within a CHC environment. As a result of ignoring, stereotyping and underestimating cultural and educational characteristics, in CHC countries, the implementation of constructivism and one of its applications—cooperative learning—has ended up in failures, suspicion or resistance. The authors would like to question (1) the fixed assumption that “group-work surely works in CHC countries” and (2) the domination of developmentalism in education nowadays and its mismatch with cultural assets. With this paper, the authors contribute to the recent call for culturally appropriate pedagogy.

Sixth Graders’ Conflict Resolution in Role Plays with a Peer,Parent, and Teacher

This study used conflict resolution role play vignettes and self-report surveys of 450 New York City 6th graders to examine associations between adolescents’ conflict resolution efficacy and social skills. Vignettes covered 3 social contexts, conflict with a peer (disagreement over activities), with a parent (raise in allowance), and with a teacher (low grade on report). Effective and ineffective strategies for resolving these conflicts were coded from the videotaped interactions. Adolescents were more often effective in resolving conflict with peers than with parents (χ²(1) = 7.10, p < .01). Strong communication skills cut across interpersonal context as associated with effective resolution. Assertiveness and absence of aggression were associated with effective conflict resolution in vignettes with peers. Assertiveness was also associated with effective conflict resolution in vignettes with parents, however nervousness was unexpectedly found to facilitate conflict resolution in vignettes with parents. Only skills observed within a particular context were associated with effective resolution in that context; self-report skills and cross-context observed skills were not associated with efficacy. Implications for implementation and evaluation of social skills curricula and conflict resolution process are discussed.An earlier version of this paper was presented at the meetings of the Society for Research on Adolescence, New Orleans, LA, April 2002Received Ph.D. in Developmental Psychology from Teachers College, Columbia University in 2004. Research interests include adolescent social competence and youth development programs.Received Ph.D. in Developmental Psychology from Pennsylvania State University in 1991. Research interests include the psychosocial correlates of puberty, stress reactivity, and health compromising behaviors and adjustment.Received Ph.D. in Developmental Psychology from Teachers College, Columbia University in 2002. Research interests include social competence, prevention research, and women’s health.Received Ph.D. in Developmental Psychology from Teachers College, Columbia University in 2002. Research interests include social competence, prevention research, and women’s health.Received Ph.D. in 1975 from University of Pennsylvania in Human Learning and Development. Research focus centers around designing and evaluating interventions aimed at enhancing the wellbeing of children living in poverty and associated conditions. Conducts research on transitional periods during childhood and adolescence, focusing on school, family and biological transitions in childhood, adolescence, and adulthood. Specific interests are in the factors that contribute to positive and negative outcomes, and changes inwell-being over these years.Received Ph.D. in Developmental Psychology from Columbia University in 1977. Research interests include tobacco, alcohol, and drug abuse prevention, violence prevention, AIDS risk reduction among adolescents, health promotion and disease prevention, smoking cessation.