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901.
Postmortem stability of DNA   总被引:11,自引:0,他引:11  
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.  相似文献   
902.
A method for the routine profiling of illicit heroin samples received in casework has been developed which depends on simple and straightforward sample pretreatment, followed by gas chromatography on a capillary column using flame-ionization detection. The factors affecting the choice of each aspect of the procedure are discussed, as are the statistical data for sampling and the chromatography. Components of illicit heroin derived from opium and other adulterants have been identified. The significance of data from samples examined in 1986 is discussed.  相似文献   
903.
904.
905.
A study of deaths due to organophosphate and related "cholinesterase-inhibiting" pesticides was performed on the case files of the office of the Medical Examiner in Metropolitan Dade County in Miami, Florida, USA. Briefly, a comparison was performed between cases which occurred between the years 1961-1965, when such pesticides were used indiscriminately and before stricter laws regulating their use were enacted, and with a series of cases occurring between the years, 1981-85, after such stricter laws were enacted. The occurrence of such deaths dropped dramatically with the decease in organophosphate use. A discussion ensues, along with specific information for the reader, on how the forensic scientist may help ameliorate their environment.  相似文献   
906.
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.  相似文献   
907.
Using interview and survey data, we argue there are three types of places in the rural United States, and that their social and economic conditions help us understand emerging political trends, including the rural support for Donald Trump. More rural votes were cast for the Republican presidential candidate in 2016 than in other recent elections, yet shifts to Republican votes were greatest in places undergoing the most significant economic transitions. Work in rural communities has been a source of pride and cultural identity for people as well as places, but many feel the new economy is not working for them.  相似文献   
908.
Thomas  Diana W.  Thomas  Michael D. 《Public Choice》2020,182(3-4):443-457

The Olsonian distinction between roving and stationary bandits outlines the rationale behind the transition from anarchy to the emergence of the predatory state. This two-bandit model may, however, be expanded to include more bandit types. In the case of Viking Age England, local English kings were unable to monopolize violence and defend their realms against competing Viking raiders. As the Vikings’ time horizon grew, so did the accumulated value of more formal taxation, and bandit types evolved in four steps. The first step is the Olsonian roving bandit, who executed Viking hit-and-run attacks and plunders during the second half of the tenth century. The second step is the gafol bandit; gafol is payment for leaving, paid to, among others, Swein Forkbeard. The third step is the heregeld bandit; heregeld is a tax to support an army for hire; most notably Thorkell the Tall’s. The fourth step is the Olsonian stationary bandit, i.e. the strongest military leader among the Vikings, Cnut the Great, settled down as the new king. Overall, the Olsonian two-bandit model can be expanded to a four-bandit staircase model, in which the new gafol and heregeld bandit types explain the steps from anarchy and short-run raiding to long-run formal taxation in a predatory state.

  相似文献   
909.
Political Behavior - Throughout her 2016 U.S. presidential campaign, Democratic Party nominee Hillary Clinton crafted messages intended to appeal to fathers of daughters and to highlight the...  相似文献   
910.
Jenkins  Jeffery A.  McCarty  Nolan  Stewart  Charles 《Public Choice》2020,185(3-4):245-251
Public Choice - Within political science, a movement focused on increasing the credibility of causal inferences (CIs) has gained considerable traction in recent years. While CI has been...  相似文献   
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