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1.
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.  相似文献   
2.
"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)  相似文献   
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This article aims to question the discourse on “the war on terror” developed by the French President in the wake of the two terrorist attacks that occurred in France in 2015. Drawing from critical discourse analysis, it explores the discursive legitimation strategies deployed by President Hollande to legitimate France’s securitarian response to the two attacks. It reveals how the defence of human rights served as an overall justificatory framework, through rationalisation, appeals to authority, and moralisation. It argues that Hollande implemented a discursive manipulation of reality to shield his actions from criticisms of illiberalism, all the while reframing the notion of human rights, undermining it and paving the way for an authoritarian-driven executive.  相似文献   
5.
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.  相似文献   
6.
Local Institutions and the Politics of Urban Growth   总被引:2,自引:0,他引:2  
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.  相似文献   
7.
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.  相似文献   
8.
Recently, a metric approach to skeletal sex determination was published by Paiva and Segre which is based on the summation of two triangular areas defined by three distinct craniometric landmarks: Porion, Mastoidale, and Asterion. According to the authors, values for the total triangle > or =1447.40 mm(2) are characteristic for male crania, while values < or =1260.36 mm(2) are indicative of female skulls (95% confidence). In order to evaluate the method's validity, two sex- and age-documented samples of different provenience were analyzed (N=197). The results show that while the indicated measurements display significant sex differences, the technique is of little practical meaning where a single individual must be independently classified. It is hypothesized that differences in the expression of sexual dimorphism as well as a population-specific variability of the asterion location undermine the value of the mastoid triangle as a sex determinant.  相似文献   
9.
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.  相似文献   
10.
Preservation variance of soil DNA is neglected in the literature, and exceptional cases exaggerate amplification capabilities. This study sought to amplify a short mitochondrial fragment (212 bp) specific to Sus scrofa domesticus from the soil surrounding decomposing pig remains from an open‐air locale. Samples collected above the body at incremental distances after 145 days of initial placement yielded pig DNA. A secondary sampling was collected in 2017, approximately 768 days after burial. Inhibition tests corroborated that pig DNA was no longer present in the soil resulting in a loss of original DNA between 145 and 768 days. The results provide evidence that genetic material leaches out radially from the source and DNA fragments longer than 200 bp do not persist in soil for a relatively short timeframe in western Montana. The conclusions support the collection of soil in crime scene investigation procedures within the first few months of decomposition.  相似文献   
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