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1.
The purpose of this study was to increase the knowledge base of adolescent substance use by examining the influences of risk and protective factors for specific substance use, namely alcohol, cigarettes, and marijuana. Participants included 271 adolescents and their primary caregivers referred for mental health services across North Carolina. A series of hierarchical multiple regressions showed that the relative influences of risk and protective factors differed depending on the target substance in some cases. History of parental felony predicted use of all 3 substances, although the direction of association was substance specific. Parental behavioral control (how families express and maintain standards of behavior) was predictive only of cigarette and marijuana use, not alcohol use. The different links among risk factors, protective factors, and specific substance use are discussed, and recommendations for both mental health and substance use professionals are offered.She received her M.A. in Psychology from Wake Forest University and is currently a doctoral student in Clinical Psychology at the University of North Carolina at Greensboro. Her major research interests include developmental pathways to aggressive behavior among females.An evaluator for the North Carolina Department of Health and Human Services, her major research interests include system of care intervention programming.She received her PhD in Clinical Psychology from Purdue University. Her major research interests include developmental psychopathology and early intervention.His research interests focus on youth violence and youth involved with the juvenile justice system.She received her PhD in Clinical Psychology from the University of North Carolina at Greensboro. Her research interests focus on early intervention with young children.  相似文献   
2.
The floral development and potencies [Δ(9) -tetrahydrocannabinol (THC) contents] of cannabis plants were compared when grown indoors under high-pressure sodium lamps consuming electrical power at three densities (270, 400, and 600 W/m(2)). After a 3-week vegetative phase, plants were grown for 8 weeks, with lamps maintaining an artificial day length of 12 h. Foliar and floral yields were measured. Gas chromatography was used to measure the content of the psychoactive cannabinoid THC. Mean yields per unit of electrical power in each lighting regime ranged from 0.9 to 1.6 g/W, the highest being achieved in the lowest irradiance regime. The individual potencies of the separated leaf and flower materials were not affected by increasing irradiance. However, there was a corresponding increase in the overall potency of the aerial plant tissue. This was because of the plants in brighter conditions producing a higher proportion of floral material.  相似文献   
3.
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.  相似文献   
4.
From November 1, 2010 through November 30, 2012, 1204 whole‐blood samples were confirmed to contain THC alone or in combination with other drugs out of nearly 5000 Orange County, California, drivers suspected of driving under the influence of drugs. The goal of this study was to examine police reports and drug recognition expert evaluations of THC‐positive samples within this 2‐year time frame to determine whether there is a correlation between whole‐blood THC concentrations and field sobriety tests performance on DRE and non‐DRE evaluations. The FSTs prove to be sensitive to impairment by marijuana although as suspected, the findings of this study did not find a correlation between performance on field sobriety tests and the concentration of THC tested in whole‐blood samples. Driving behaviors were also examined and found to be similar to those seen in alcohol impairment. Future studies examining DRE findings are needed to confirm the results.  相似文献   
5.
The validity and feasibility of using DNA collection cards in the field for preservation and analysis of Cannabis sativa genotypes were investigated using a highly specific hexanucleotide marker. Collection cards were submitted to the National Marijuana Initiative, which selectively trained and managed the collection of specific types of samples from a variety of participating agencies. Samples collected at seizure sites included fresh marijuana leaf samples, dried "dispensary" samples, U.S. border seizures, and hashish. Using a standardized PCR kit with custom-labeled oligonucleotide primers specific to marijuana, collection cards produced eight genotypes and 13 different alleles, extremely low baselines, and no cross-reactivity with control plant species. Results were produced from all sample types with the exception of hashish. Plant DNA collection cards represent an easily implementable method for the genetic identification and relatedness of C. sativa street and grow site-seized samples with applications for databasing and market disruption.  相似文献   
6.
Abstract: The University of Mississippi has a contract with the National Institute on Drug Abuse (NIDA) to carry out a variety of research activities dealing with cannabis, including the Potency Monitoring (PM) program, which provides analytical potency data on cannabis preparations confiscated in the United States. This report provides data on 46,211 samples seized and analyzed by gas chromatography‐flame ionization detection (GC‐FID) during 1993–2008. The data showed an upward trend in the mean Δ9‐tetrahydrocannabinol (Δ9‐THC) content of all confiscated cannabis preparations, which increased from 3.4% in 1993 to 8.8% in 2008. Hashish potencies did not increase consistently during this period; however, the mean yearly potency varied from 2.5–9.2% (1993–2003) to 12.0–29.3% (2004–2008). Hash oil potencies also varied considerably during this period (16.8 ± 16.3%). The increase in cannabis preparation potency is mainly due to the increase in the potency of nondomestic versus domestic samples.  相似文献   
7.
Whole blood samples were examined for ?9‐Tetrahydrocannabinol (THC) over 2 years in drivers suspected of driving under the influence. Part one of the study examined the link between [THC] and performance on field sobriety tests. This portion examined objective signs, eye examinations and physiological indicators; and their relationship to the presence of THC. Several objective signs were excellent indicators of the presence of THC: red eyes (94%), droopy eyelids (85.6%), affected speech (87.6%), tongue coating (96.2%), and odor of marijuana (82.4%). About 63.6% of THC positive subjects had dialted pupils (room light). THC positive subjects had either rebound dilation or hippus in 88.8% of cases. Pulse and blood pressure (BP) were evaluated to determine any correlation with [THC]. An increased pulse rate correlated well to the presence of THC (88.5%), but not [THC]. BP did not correlate to [THC] and was also a poor indicator of THC in the blood (50% high).  相似文献   
8.
目的比较电喷雾电离(ESI)和大气压化学电离(APCI)两种模式对大麻酚类物质的离子化效果。方法采用UFLC-(ESI/APCI)MS分析方法,分别考察使用ESI和APCI时雾化电压、雾化气流量、干燥气流量、加热块温度、解离管温度等参数变化对大麻酚类物质的影响规律,确定最优条件参数组合,并比较ESI和APCI对大麻酚类物质的离子化效果。结果对于0.5μg/mL大麻二酚、大麻酚和四氢大麻酚标准品,ESI峰高分别为215 006、143 051、216 944,信噪比41.74、49.88、42.12,峰面积日内标准偏差(RSD)<3.96%;APCI峰高分别为140 238、226 505、247 753,信噪比78.37、131.03、138.46,峰面积日内标准偏差(RSD)<11.98%。结论检测大麻样品时,ESI为首选,基质复杂时可以使用APCI作为ESI的补充手段。  相似文献   
9.
In the United States, federal law and many state laws differentiate between marijuana and industrial hemp through delta-9-tetrahydrocannabinol (THC) levels, whereby the latter is defined as ≤0.3 percent THC on a dry weight basis. Many traditional cannabis identification methods employed by crime laboratories cannot accurately determine total THC quantities in accordance with federal and state regulations, or do so with increased time, labor, and risks of instrument damage. In order to quickly distinguish positive marijuana samples, a method was developed to identify plant material with a total THC level >1%. This novel, automated dispersive pipette extraction (DPX) method uses tip-based technology and an automated liquid handler to enable fast, hands-free selective isolation of THC and its precursors for downstream gas chromatography–mass spectrometry (GC-MS) analysis. The workflow proceeds with no repetitive manual effort and reduced need for instrument maintenance while enabling crime labs to legally identify marijuana through the detection of total THC above 1%. Recovery of THC using the DPX extraction method was 93% at 30 µg/mL and 78% at 500 µg/mL. Similarly, THCA-A recovery was 100% at 30 µg/mL and 74% at 500 µg/mL. Samples evaluated in a blind study (proficiency, hemp, and nonprobative case samples) were all accurately identified as greater than or less than 1% THC, with samples containing <1% THC being identified as “cannabis” and subjected to more discriminative analysis as needed.  相似文献   
10.
Older adults are at elevated risk of reducing labor supply due to poor health, partly because of high rates of symptoms that may be alleviated by medical marijuana. Yet, surprisingly little is known about how this group responds to medical marijuana laws (MMLs). We quantify the effects of state medical marijuana laws on the health and labor supply of adults age 51 and older, focusing on the 55 percent with one or more medical conditions with symptoms that may respond to medical marijuana. We use longitudinal data from the Health and Retirement Study to estimate event study and differences‐in‐differences regression models. Three principle findings emerge from our analysis. First, active state medical marijuana laws lead to lower pain and better self‐assessed health among older adults. Second, state medical marijuana laws lead to increases in older adult labor supply, with effects concentrated on the intensive margin. Third, the effects of MMLs are largest among older adults with a health condition that would qualify for legal medical marijuana use under current state laws. Findings highlight the role of health policy in supporting work among older adults and the importance of including older adults in assessments of state medical marijuana laws.  相似文献   
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