Determination of MDMA, MDA, MDEA and MBDB in oral fluid using high performance liquid chromatography with native fluorescence detection

This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.     

Mortality in Mexico. Some considerations on rural-urban differentials

"In this essay, certain aspects related to rural-urban mortality differentials in Mexico are analyzed....[These include] the availability, advantages, and limitations of different sources of information and the disparity of levels and tendencies according to particular indicators of acceptable reliability, especially those deriving from recent demographic surveys conducted in Mexico. The findings confirm an inverse ratio between size of settlement and mortality, and reveal a widening of the differentials over time." (SUMMARY IN ENG)     

Gettin’ Down Home With the Neelys: gastro-porn and televisual performances of gender,race, and sexuality

This article illuminates how performances of gender, race, and sexuality are integrated with representations of food and food performance in contemporary American cooking television. Interrogating the intersections of food, gender, race, sexuality, and performance, this essay explores how the cable-television show, Down Home with the Neelys, depicts a nouveau gastro-porn anchored in the perceived pornographic level of blackness itself. The author reveals the ways that food and performances of food become a medium of gendering and racialization employed by American popular media. Through the lens of reality television, shows like Down Home (re)produce a certain type of black heterosexuality and gendered enactments of domesticity and space, while challenging dominant televisual reflections of black love and labor. The author argues that the Neelys self-consciously employ a vernacular aesthetic performative of “down home” (a uniquely classed, temporally–spatially situated, and sexualized blackness) to exploit the phenomenon of gastro-porn in a highly lucrative performance that signals the entangled artifice of gender, race, and sexuality. More than offering culinary expertise and education, such cooking instruction reveals the pedagogy of gender, race, and sexuality as visual lessons of a complex and contradictory authenticity. This essay reveals television cooking shows as critical sites for considering the domestic laboring of gendered and racialized sexualities. In particular, shows like Down Home evince the ways that race continues to be rendered in visual terms and the enduring edibility of blackness.     

Local Institutions and the Politics of Urban Growth

This article uses a political market framework to analyze how the structure of local political institutions affects the relative political influence of development and environmental interests in the context of urban growth. Using panel data from 406 Florida cities from 1998 to 2003, the empirical analysis finds important interaction effects between the structure of city executive branch institutions and interest group variables. The economic and political forces driving urban growth do not operate identically in all cities—they vary as a function of institutional context. Institutional structure helps determine which interest groups have their preferences reflected in local land-use changes and development patterns. The resulting patterns suggest a "sustainability paradox" wherein richer, environmental interests push for the preservation of environmental amenities while at the same time accelerating the number of residential units built in a community.     

Characterization of human DNA in environmental samples

Environmental samples from indoor surfaces can be confounded by dust, which is composed largely of human skin cells and has been documented to contain roughly tens of micrograms of total DNA per gram of dust. This study complements previous published work by providing estimates of the quantity of amplifiable human DNA found in environmental samples from a typical indoor environment, categorized by the intensity of human traffic and visible quantity of dust. Dust was collected by surface swabbing standard 576 cm² areas in eight locations, and evaluated for total DNA quantity, presence of human DNA (mitochondrial and nuclear loci using conventional PCR), quantity of human nuclear DNA using quantitative PCR, and STR analysis. The total DNA content of 36 dust samples ranged from 9 to 28 ng/cm², and contained 0.2–1.1 pg/cm² of human DNA. Overall, human DNA was detected in 97% of 36 dust samples and 61% of samples yielded allele distributions of varying degrees of complexity when subjected to STR analysis. The implications of this study are twofold. First, the presence of dust in evidence can be a significant contamination source in forensic investigations because the human DNA component is of sufficient quality and quantity to produce allele calls in STR analysis. This can be effectively managed by implementing stringent protocols for collection and analysis of potential biological samples. A second implication is the use of dust as a source of evidence for identification of inhabitants within a defined location. In the latter case, a number of additional studies would be necessary to identify relevant pretreatments for environmental dust samples and to develop the necessary deconvolution techniques to separate the composite genotypes obtained.     

From Renascer to Velho Chico: negotiations between cordiality and modernity in the Brazilian telenovela

ABSTRACT

This article takes as its focus the main Brazilian cultural and media product, the telenovela or soap opera, to discuss the characteristic of the Brazilian personality referred to as the homem cordial (“cordial man”). The article analyses two telenovelas: Renascer (1993) and Velho Chico (2016), which, written by the same author, but in very different historical contexts, sought to recover the trait of cordiality in its essence. In its comparison of the two telenovelas, this study presents and discusses the changes, permanencies and negotiations of a cordial tradition in the face of a particular aspect of modernity represented by both the process of urbanisation and by television itself.     

Multiplex short tandem repeat amplification of low template DNA samples with the addition of proofreading enzymes

Abstract:  With <100 pg of template DNA, routine short tandem repeat (STR) analysis often fails, resulting in no or partial profiles and increased stochastic effects. To overcome this, some have investigated preamplification methods that include the addition of proofreading enzymes to the PCR cocktail. This project sought to determine whether adding proofreading polymerases directly in the STR amplification mixture would improve the reaction when little template DNA is available. Platinum Taq High Fidelity and GeneAmp High Fidelity were tested in Profiler Plus? STR reactions alone and in combination with AmpliTaq^® Gold. All reactions included the additional step of a post‐PCR purification step. With both pristine low template DNA and casework samples, the addition of these polymerases resulted in comparable or no improvement in the STR amplification signal. Further, stochastic effects and artifacts were observed equally across all enzyme conditions. Based on these studies, the addition of these proofreading enzymes to a multiplex STR amplification is not recommended for low template DNA work.     

Recovery of Environmental Human DNA by Insects*,†

Abstract: We tested the hypotheses that foraging insects can acquire human DNA from the environment and that insect‐delivered human DNA is of sufficient quantity and quality to permit standard forensic analyses. Houseflies, German cockroaches, and camel crickets were exposed to dusty surfaces and then assayed for human mitochondrial and nuclear loci by conventional and qPCR, and multiplex STR amplification. Over two experiments, 100% of insect groups and 94% of dust controls tested positive for human DNA. Of 177 individuals, 33–67% tested positive and 13 yielded quantifiable human DNA (mean = 0.022 ± 0.006 ng; mean dust control = 2.448 ± 0.960 ng); four had at least one positive allele call for one or more locus; eight others showed multiple peaks at some loci. Results imply that application to routine forensic casework is limited given current detection methodology yet demonstrate the potential use of insects as environmental samplers for human DNA.     

Evaluation of a Freezer Mill for Bone Pulverization prior to DNA Extraction: An Improved Workflow for STR Analysis

Traditional methods for bone pulverization typically generate heat, risking stability of DNA sample. SPEX? has developed cryogenic grinders which introduce liquid nitrogen to cool the sample and aid in the grinding process. In this study, the Freezer Mill 6970 EFM was used with two DNA extraction methods and routine downstream STR analysis procedures. DNA from as little as 0.1 g of bone powder was used to develop full STR profiles after freezer mill pulverization, and the method was reproducible. Further, no contamination was detected upon cleaning/reuse of the sample vials. There were no significant differences in DNA yield, STR alleles detected, or peak heights using the freezer mill as compared to traditional grinding, and successful DNA profiles were achieved from as low as 0.1 g of bone powder with this method. Overall, this work indicates that this cryogenic mill method may be used as a viable alternative to traditional tissue grinders.