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131.
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.  相似文献   
132.
In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Δ(9)-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants' flowering to identify drug-type cannabis generally cultivated in Europe.  相似文献   
133.
Acid scavengers are frequently used as stabilizer compounds in a variety of applications. When used to stabilize volatile compounds such as nerve agents, the lower volatility and higher stability of acid scavengers make them more persistent in a post-event forensic setting. Compound-specific isotope analysis of carbon, nitrogen, and hydrogen in three acid-scavenging compounds (N,N-diethylaniline, tributylamine, and triethylamine) were used as a tool for distinguishing between different samples. Combined analysis of multiple isotopes improved sample resolution, for instance differentiation between triethylamine samples improved from 80% based on carbon alone to 96% when combining with additional isotope data. The compound-specific methods developed here can be applied to instances where these compounds are not pure, such as when mixed with an agent or when found as a residue. Effective sample matching can be crucial for linking compounds at multiple event sites or linking a supply inventory to an event.  相似文献   
134.
The Supreme Court's unanimous decision in Belmont Park Investments Pty Ltd v BNY Corporate Trustee Services Ltd and Lehman Brothers Special Financing Inc is of major significance to lenders, especially those in the global structured finance market. This case confirms the validity of commonly used insolvency‐triggered secured‐priority flip clauses, and, more generally, suggests a dramatically reduced role for the common law anti‐deprivation principle. The decision may not fully resolve market uncertainty, however, given the particular analysis adopted in the case itself (analysed here) and its divergence from the US statutory approach to the same principle.  相似文献   
135.
U.S. citizens who marry foreign nationals may petition for their spouses so that the couple can reside permanently together in the United States. The guidelines set forth in the U.S. Citizenship and Immigration Services Adjudicator's Field Manual provide guidance to immigration officials for determining whether to grant or deny spousal petitions. Previously, the Adjudicator's Field Manual imposed a requirement that transgender individuals undergo costly and dangerous sex reassignment surgery in order to qualify as married for the purposes of a spousal petition. However, revisions to the Adjudicator's Field Manual issued in April 2012 provide transgender binational couples the opportunity to remain together in the United States without forcing one partner to undergo sex reassignment surgery. Given the history of discrimination against transgender individuals under U.S. immigration law, these revisions are a significant step in equality for transgender couples. Although these revisions provide many transgender binational couples with a means to remain together in the United States, this Note proposes that, to continue on the path toward equality for transgender couples, special guidelines should not be applied to marriages involving transgender partners if their marriage is deemed a valid heterosexual marriage in the state where solemnized. The goals of U.S. immigration law and compliance with the federal definition of marriage can be achieved without implementing individualized guidelines for transgender binational couples.
    Key Points for the Family Court Community:
  • Transgender spouses of a binational couple should not be subjected to additional guidelines when submitting spousal petitions that, if granted, would afford the couple the opportunity to reside together in the United States
  • Transgender individuals should not be subjected to disparate treatment solely because the U.S. Citizenship and Immigration Services seeks to enforce discriminatory provisions of the Defense of Marriage Act
  • A marriage should be recognized by immigration law if it is a valid marriage under the law of the state where the marriage was celebrated
  • In order to achieve U.S. immigration law's mission of family unification, nontraditional couples should be afforded the same opportunity to remain together in the United States without additional scrutiny
  相似文献   
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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   
139.
Drug-facilitated sexual assault (DFSA) has been defined as the use of a chemical agent to facilitate a sexual assault. We report two cases of the use of tetrahydrozoline for DFSA. We believe this is the first report with urinary quantification of tetrahydrozoline levels postassault. Blood and urine were obtained c. 20 h postexposure in two cases of reported DFSA. Tetrahydrozoline was not detected in blood but was identified in urine in both victims. After initial identification in the urine using the 2010 update to the AAFS mass spectrometry database library, tetrahydrozoline was quantified at 114 and 150 ng/mL, respectively, using GC/MS. Two unique clinical features reported in these cases were intermittent periods of consciousness and postexposure vomiting. Use of GC/MS was successful in identifying tetrahydrozoline in the 100 ng/mL range up to 20 h postexposure. For victims with late presentation, urine may be a better sample for evaluation for tetrahydrozoline.  相似文献   
140.
This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900-1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry.  相似文献   
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