Mass, NMR and IR spectroscopic characterization of pentedrone and pentylone and identification of their isocathinone by-products

This study presents and discusses the mass spectrometric, nuclear magnetic resonance spectroscopic and infrared spectroscopic data of the designer drugs pentedrone (2-methylamino-1-phenylpentan-1-one) and its methylenedioxy analog pentylone (2-methylamino-1-(3,4-methylenedioxyphenyl)pentan-1-one). The structure elucidation of the aliphatic parts was carried out by product ion spectroscopy of the immonium ion with m/z=86 formed after electron ionization, and by one- and two-dimensional (1)H- and (13)C-NMR spectroscopy on the hydrochloride salts to verify the structure of the alkyl side chain and to determine the methylenedioxy position in the aromatic ring of pentylone. Furthermore, two typical cathinone synthesis by-products were detected besides the main compounds. Their mass spectra are discussed and for one of them (1-methylamino-1-phenylpentan-2-one (isopentedrone)) a NMR assignment was possible in the existing mixture.     

Screening and quantification of antipsychotic drugs in human brain tissue by liquid chromatography-tandem mass spectrometry: application to postmortem diagnostics of forensic interest

A quantitative LC-MS/MS method has been developed for the simultaneous determination of 17 antipsychotic drugs in human postmortem brain tissue. Sample preparation was performed using Hybrid Solid Phase Extraction-Precipitation technology for the removal of endogenous protein and phospholipid interferences. The chromatographic separation was performed for 16 min on a C8 column, which used a gradient elution of formate ammonium and acetonitrile, and a flow rate gradient. Triple quadrupole mass spectrometry was employed to generate tandem mass spectrometric (MS/MS) data of the target analytes to select the ion m/z signals. Quantitation of the analytes was performed by operating in the dynamic multiple reaction monitoring (dMRM) mode using an electrospray ionization interface. Calibration curves prepared in the spiked brain tissue were linear in the range 20-8000 ng/g (r(2)>0.993) for all drugs (except olanzapine). Within- and between-day coefficients of variation were lower than 25% for all drugs at the LOQ. The LOQ in the matrix ranged between 2 ng/g and 80 ng/g. The method was successfully applied to the unequivocal identification and accurate quantification of antipsychotic drugs in human postmortem brain tissues: therefore, this method can be used in forensic investigations.     

Objective paper structure comparison: Assessing comparison algorithms

More than just being a substrate, paper can also provide evidence for the provenance of documents. An earlier paper described a method to compare paper structure, based on the Fourier power spectra of light transmission images. Good results were obtained by using the 2D correlation of images derived from the power spectra as a similarity score, but the method was very computationally intensive. Different comparison algorithms are evaluated in this paper, using information theoretical criteria. An angular invariant algorithm turned out to be as effective as the original one but 4 orders of magnitude faster, making the use of much larger databases possible.     

Sex Offenders of East Asian Heritage Resemble Other Canadian Sex Offenders

Although there is considerable research on Caucasian sexual offenders, there has been much less research on sex offenders of Asian heritage. The current study compared East Asian (e.g., Chinese, Japanese, and Korean) sex offenders in British Columbia (B.C.), Canada, and other B.C. sex offenders on items and total score of Static-99R. This study included all provincially sentenced adult male sexual offenders (n = 4580) supervised in the community by B. C. Corrections (including 122 East Asian sex offenders). Sexual, violent, any crime, and any recidivism (including technical violations) data were collected with an average follow-up 4.3 years. The total scores of Static-99R were similar between East Asian sex offenders and other ethnic groups (M = 2.0 vs. M = 2.4). East Asian offenders scored significantly lower than other ethnic offenders on several items measuring general criminality (e.g., prior non-sexual violence, prior sentencing dates, and any prior sex offenses). In contrast, Asian offenders appeared to be more paraphilic (e.g., any convictions for non-contact sex offenses). Lastly, Static-99R significantly predicts sexual, violent, and criminal among sex offenders of East Asian heritage.     

Acid alteration of several ignitable liquids of potential use in arsons

Ignitable liquids such as fuels, alcohols and thinners can be used in criminal activities, for instance arsons. Forensic experts require to know their chemical compositions, as well as to understand how different modification effects could impact them, in order to detect, classify and identify them properly in fire debris. The acid alteration/acidification of ignitable liquids is a modification effect that sharply alters the chemical composition, for example, of gasoline and diesel fuel, interfering in the forensic analysis and result interpretation. However, to date there is little information about the consequences of this effect over other accelerants of interests. In this research paper, the alteration by sulfuric acid of several commercial thinners and other accelerants of potential use in arsons is studied in-depth. For that purpose, spectral (by ATR-FTIR) and chromatographic (by GC–MS) data were obtained from neat and acidified samples. Then, the spectral and chromatographic modifications of each studied ignitable liquid were discussed, proposing several chemical mechanisms that explain the new by-products produced and the gradual disappearance of the initial compounds. Hydrolysis, Fischer esterification and alkylation reactions are involved in the modification of esters, alcohols, ketones and aromatic compounds of the studied ignitable liquids. This information could be crucial for correctly identifying these accelerants. Additionally, an exploratory analysis revealed that some of the most altered ignitable liquid samples might be very similar with each other, which could have impact on casework.     

Radical Change at the Ballot Box: Causes and Consequences of Electoral Behavior in Venezuela's 2000 Elections

This study aims to explain the victory of Hugo Chávez and his party in the 2000 Venezuelan elections, to analyze the factors that made this victory possible, and to examine the consequences for future developments in the Venezuelan political system. The decay of traditional party loyalties without the emergence of new parties deeply rooted in society (dealignment without realignment); underdevelopment; and an institutional setting dominated by a president elected by a plurality electoral system have opened the door to personality-centered politics and weak parties, which are the main features of the current political situation. Compared to the 1993 and 1998 elections, the 2000 elections once again confirm an increase in personality politics and the decay of parties as instruments for articulating interests, representation, and governance. As a consequence, this article argues, instability is likely to remain a feature of Venezuela's party system for some time.