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The present study aims at validating the Cannabis Abuse Screening Test (CAST) in a clinical sample of adolescent and young adult cannabis users seeking treatment. Applying a classical test theory approach using DSM-IV diagnoses as gold standard, two versions of the CAST questionnaire are compared. The sample consisted of 140 subjects aged 15-26 years (mean 18.9) recruited from two cannabis treatment centers. Gold standard diagnoses were assessed using the Adolescent Diagnostic Interview-Light. Internal structure and consistency of the CAST were assessed by principal component analysis and Cronbach's α. Optimal thresholds were defined using receiver operating characteristic analysis. Both the binary and the full test version revealed unidimensional structures with moderate to satisfactory internal consistency (α = 0.66 and 0.73). Screening properties were unsatisfactory when the CAST was compared against cannabis dependence. With regard to cannabis use disorders, both test versions yielded comparable and good sensitivity and specificity at cut-off 3 (binary: 92.2%, 66.7%) and 6 (full: 93.0%, 66.7%). Overall, the full CAST may be used for screening cannabis use disorders in clinical settings. Further research may use validation methods that do without gold standard.  相似文献   
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Fused thieno[3,2-d]thiazoles were synthesized via a coupling of acetophenone ketoximes, arylacetic acids, and elemental sulfur in the presence of Li2CO3 base. Functionalities including chloro, bromo, fluoro, trifluoromethyl, and pyridyl groups were compatible with reaction conditions. High yields and excellent regioselectivities were obtained even if meta-substituted ketoxime acetates were used. Ethyl esters of heteroarylacetic acids were competent substrates, which is very rare in the literature. Our method would offer a convenient protocol to afford polyheterocyclic structures from simple substrates.

Annulation of acetophenone oxime acetates, arylacetic acids or esters, and elemental sulfur in absence of transition metals is reported.  相似文献   
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In this study, the effect of graphene nanoplatelet (GNP) size on the microstructure and hardness of the electrodeposited nickel–graphene nanocomposite coatings were investigated. GNPs with different sizes were prepared by using a high energy ball milling technique. The experimental result revealed the high energy ball milling technique could reduce the size, increase the surface area, and improve the dispersion ability of GNPs. The microstructure, hardness, and components of the nanocomposite coatings were greatly affected by GNP sizes. The highest microhardness was measured to be 273 HV for the nanocomposite coatings containing 5 h-milled GNPs, which is increased up to ∼47% compared to pristine Ni coating. The enhancement in the hardness is attributed to the uniform dispersion of the small GNP sizes inside the Ni matrix and the Ni grain size reduction when using milled GNPs.

The effect of graphene nanoplatelet size on the microstructure and hardness of electrodeposited nickel–graphene nanocomposite coatings was investigated.  相似文献   
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Parental addictions have been associated with adult children’s depression in several clinical and population-based studies. However, these studies have not examined if gender differences exist nor have they controlled for a range of potential explanatory factors. Using a regionally representative sample of 6268 adults from the 2005 Canadian Community Health Survey (response rate=83%), we investigated the association between parental addictions and adulthood depression controlling for four clusters of variables: adverse childhood experiences, adult health behaviors, adult socioeconomic status and other stressors. After controlling for all factors, adults exposed to parental addiction had 69% higher odds of depression compared to their peers with non-addicted parents (OR=1.69; 95% CI, 1.25–2.28). The relationship between parental addictions and depression did not vary by gender. These findings underscore the intergenerational consequences of drug and alcohol addiction and reinforce the need to develop interventions that support healthy childhood development.  相似文献   
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