Postmortem stability of DNA

High-molecular-weight DNA was recovered postmortem in sufficient quantities from various human organ tissues as well as from blood, although not all organs were equally well suitable. Good DNA stability was found in brain cortex, lymph nodes and psoas muscle over a period of three weeks postmortem. Spleen and kidney showed good DNA stability up to five days postmortem but after longer periods, rapid degradation was observed. Yields of DNA from blood were not consistent because of the non homogeneity of samples. Blood clots were rich with DNA. Generally, the amount of degraded DNA correlated directly with the duration of the postmortem period. However in some cases, DNA degradation was already prominent after a short period. However in some cases, DNA degradation was already prominent after a short period. Case histories showed that high environmental temperature at the site of death and/or infectious diseases prior to death were the main factors for rapid autolysis. Gradual disappearance to complete loss of the long fragments (15-23 kb) was observed in DNA fingerprinting using the minisatellite probe 33.15. No extra-bands were noted, thus excluding erroneous conclusions. However, evidentiary value of older samples was lower.     

Relationship between the concentration of ethanol and methanol in blood samples from Swedish drinking drivers

Headspace gas chromatography was used to determine the concentration of ethanol and methanol in blood samples from 519 individuals suspected of drinking and driving in Sweden where the legal alcohol limit is 0.50 mg/g in whole blood (11 mmol/l). The concentration of ethanol in blood ranged from 0.01 to 3.52 mg/g with a mean of 1.83 +/- 0.82 mg/g (+/- S.D.). The frequency distribution was symmetrical about the mean but deviated from normality. A plot of the same data on normal probability paper indicated that it might be composed of two subpopulations (bimodal). The concentration of methanol in the same blood specimens ranged from 1 to 23 mg/l with a mean of 7.3 +/- 3.6 mg/l (+/- S.D.) and this distribution was markedly skew (+). The concentration of ethanol (x) and methanol (y) were positively correlated (r = 0.47, P less than 0.001) and implies that 22% (r2) of the variance in blood-methanol can be attributed to its linear regression on blood-ethanol. The regression equation was y = 3.6 + 2.1 x and the standard error estimate was 0.32 mg/l. This large scatter precludes making reliable estimates of blood-methanol concentration from measurements of blood-ethanol concentration and the regression equation. But higher blood-methanol concentrations are definitely associated with higher blood-ethanol in this sample of Swedish drinking drivers. Frequent exposure to methanol and its toxic products of metabolism, formaldehyde and formic acid, might constitute an additional health risk associated with heavy drinking in predisposed individuals. The determination of methanol in blood of drinking drivers in addition to ethanol could indicate long-standing ethanol intoxication and therefore potential problem drinkers or alcoholics.     

基于区域经济发展视角下的人才培养模式创新研究——红旗大学管理系人才培养模式创新研究

随着互联网经济的发展、教学资源竞争的加剧、普通高等教育规模的扩张以及我国高等教育由精英教育向大众化教育的转变,给成人高校的教育教学提出了严峻的挑战,在新形势下探索成人学校教学方法和教学手段的完善已是当务之急。成人高校如何有效地实现成人学习自主、合作、探究学习的教学理念,不断提高学生的创新意识和能力,培养满足区域经济发展急需的应用型、技能型人才正是本文要研究的问题。     

drones,swarms and becoming-insect: feminist utopias and posthuman politics

Insects and ‘the swarm’ as metaphors and objects of research have inspired works in the genres of science fiction and horror; social and political theorists; and the development of war-fighting technologies such as ‘drone swarms’, which function as robot/insect hybrids. Contemporary developments suggest that the future of warfare will not be ‘robots’ as technological, individualised substitutions for idealised (masculine) warfighters, but warfighters understood as swarms: insect metaphors for non-centrally organised problem-solvers that will become technologies of racialisation. As such, contemporary feminist analysis requires an analysis of the politics of life and death in the insect and the swarm, which, following Braidotti (2002), cannot be assumed to be a mere metaphor or representation of political life, but an animating materialist logic. The swarm is not only a metaphor but also a central mode of biopolitical and necropolitical war, with the ‘terrorist’ enemy represented as swarm-like as well. In analysing the relations of assemblage and antagonism in the war ontologies of the drone swarm, I seek inspiration from what Hayles (1999, p. 47) describes as a double vision that ‘looks simultaneously at the power of simulation and at the materialities that produce it’. I discuss various representations and manifestations of swarms and insect life in science/speculative fiction, from various presentations of the ‘Borg’ in Star Trek (1987–1994, 1995–2001, 1996), Alien (1979) and The Fly (1958, 1986) to more positive representations of the ‘becoming-insect’ as possible feminist utopia in Gilman’s Herland (2015 [1915]) and Tiptree’s Houston, Houston, Do You Read? (1989 [1976]). Posthuman warfare also contains the possibilities of both appropriating and rewriting antagonisms of masculine and feminine in the embodiment of the subject of war in the swarm. This piece seeks to analyse new ways of feminist theorising of the relations of power and violence in the embodiment of war as the swarm.     

Developmental Associations Between Adolescent Change in Depressive Symptoms and Menstrual-Cycle-Phase-Specific Negative Affect During Early Adulthood

The causal factors associated with increases in depressive symptoms among adolescent girls remain an area of theoretical debate, and the limited research considering a hormonal influence has provided mixed results. The goal of the present study was to test a set of longitudinal associations, that, if found, would provide support for a hormonal contribution to these changes. Specifically, this study tested the hypotheses that changes in depressive symptoms among adolescent girls would be associated with phase-specific symptoms of the menstrual cycle during early adulthood; that these associations would differ across three phases of the menstrual cycle; and that the pattern of associations would differ for changes in depressive symptoms during early- and late-adolescence. The sample consisted of 47 women with longitudinal data from 12 to 21 years old (approximately 91% European Canadian, 4% Middle Eastern Canadian, 2% Haitian Canadian, and 2% Asian Canadian). Consistent with expectations, results showed that early-adolescent increases in depressive symptoms were negatively associated with menstrual-phase negative affect, and positively associated with mid-cycle negative affect, but not associated with premenstrual negative affect; whereas late-adolescent change in depressive symptoms was only associated with depressive symptoms at 20-21 years. Thus, early-adolescent changes in depressive symptoms are longitudinally associated with later mood change across the menstrual cycle, suggesting a common underlying cause, which is hypothesized to be hormonal. Moreover, results suggest that, with respect to variables that are involved in affective development, important differences exist between early- and late-adolescence. The discussion considers menstrual-cycle-related symptoms (e.g., dysmenorrhea) during adolescence, and the need to study their effects on development. It is suggested that focused intervention and prevention efforts may be indicated to interrupt negative developmental outcomes.