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31.
The authors present information about anatomical and topographical peculiarities of the patterns of the mucous membrane at the backside surface of the tongue in the immediate and late postmortem periods. The apparent dynamics of the structural changes on this surface does not exclude the possibility of using them as the criteria for personality identification within 1 month after death.  相似文献   
32.
The authors report the results of a forensic medical investigation of 6 cases of death associated with the administration of pharmaceutical products documented by forensic medical experts of the Russian Centre of Forensic Medical Expertise. The results of the study are compared with the clinical data and summarized using the methods of tanatogenetic analysis. The following main clinical variants of iatrogenic anaphylactic shock (IAS) are distinguished: bronchospastic IAS (n = 1), asphyxic IAS (n = 1), hemodynamic IAS (n = 3), and combined (bronchospastic plus hemodynamic) IAS (n = 1). The signs of all these variants are described allowing for their diagnostics and differentiation diagnostics. These data can be used for the purpose of forensic medical diagnostics and elucidation of the mechanisms of tanatogenesis.  相似文献   
33.
Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported.  相似文献   
34.
Despite financial innovations that have created important new substitutes for cash usage, per capita holdings of U.S. currency amount to $2950. Yet American households and businesses admit to holding only 15% of the currency stock, leaving the whereabouts of 85% unknown. Some fraction of this unaccounted for currency is held abroad (the dollarization hypothesis) and some is held domestically undeclared, as a store of value and a medium of exchange for transactions involving the production and distribution of illegal goods and services, and for transactions earning income that is not reported to the IRS (the unreported economy hypothesis). We find that the percentage of U.S. currency currently held overseas is between 30 and 37% rather than the widely cited figure of 65%. This finding is based on the official Federal Reserve/Bureau of Economic Analysis data which is a proxy measure of the New York Federal Reserve’s (NYB) “confidential” data on wholesale currency shipments abroad. We recommend that the NYB data be aggregated so as to circumvent confidentiality concerns, and be made readily available to all researchers in order to shed greater light on the questions of how much U.S. currency is abroad and on the particular location of overseas U.S. dollars. The newly revised official estimates of overseas currency holdings are employed to determine the Federal Reserve’s seigniorage earnings from 1964–2010, which have provided a $2950. Yet American households and businesses admit to holding only 15% of the currency stock, leaving the whereabouts of 85% unknown. Some fraction of this unaccounted for currency is held abroad (the dollarization hypothesis) and some is held domestically undeclared, as a store of value and a medium of exchange for transactions involving the production and distribution of illegal goods and services, and for transactions earning income that is not reported to the IRS (the unreported economy hypothesis). We find that the percentage of U.S. currency currently held overseas is between 30 and 37% rather than the widely cited figure of 65%. This finding is based on the official Federal Reserve/Bureau of Economic Analysis data which is a proxy measure of the New York Federal Reserve’s (NYB) “confidential” data on wholesale currency shipments abroad. We recommend that the NYB data be aggregated so as to circumvent confidentiality concerns, and be made readily available to all researchers in order to shed greater light on the questions of how much U.S. currency is abroad and on the particular location of overseas U.S. dollars. The newly revised official estimates of overseas currency holdings are employed to determine the Federal Reserve’s seigniorage earnings from 1964–2010, which have provided a 287 billion windfall for U.S. taxpayers. Overseas currency stock data are also used to derive estimates of the domestically held stock of currency as well as narrow and broad measures of domestic monetary aggregates. These domestic monetary aggregates are believed to be better predictors of future economic activity than traditional monetary aggregates and are tested to determine their ability to predict fluctuations in real output and prices. Domestic cash holdings are finally used to estimate the size of the U.S. unreported economy as measured by the amount of income that is not properly reported to the IRS. By 2010, we estimate that legal and illegal source unreported income” is $1.9–$1.9–2.4 trillion, implying a “tax gap” in the range of $400–$400–540 billion. Currently, we estimate that 18–23% of total reportable income is not properly reported to the IRS.  相似文献   
35.
The results of extraction of lambda-cigalotrin from dioxan aqueous solutions by hydrophobic organic solvents are presented. It is shown that the degree of extraction depends on the nature of the extractant, the water to dioxan ratio, and saturation of the water-dioxan layer with the electrolyte. The highest efficiency of lambda-cigalotrin extraction was achieved using chlorophorm as a solvent under desalination conditions. The extraction factor was calculated necessary to obtain the desired amount of lambda-cigalotrin from the water-dioxan solution (4:1) with the help of the extractants being used.  相似文献   
36.
37.
Several assays for gamma-hydroxybutyrate (4-hydroxybutyrate, GHB) have been developed based on the enzyme gamma-hydroxybutyrate dehydrogenase (GHB-DH). Enzymatic oxidation of GHB by NAD+ is coupled to diaphorase-mediated reduction of pro-dye to yield colored product. GHB-DH from Ralstonia eutropha was cloned and expressed as a stable fusion protein easily purified by affinity chromatography. Quantitative initial velocity and endpoint versions of the assay in solution are described. Michaelis-Menten parameters for oxidation of GHB and ethanol were estimated. A semi-quantitative "dipstick" version of the assay on paper also is described. Both solution endpoint and "dipstick" assays are sensitive to about 0.05 mg GHB/mL using 10 microL of sample. Ethanol at concentrations possible in urine and agents used to stabilize physiological fluids for forensics analysis do not interfere significantly. The "dipstick" assay also allows detection of GHB in alcoholic beverages after evaporation of about one-fourth drop of beverage before testing. The enzymatic assay for GHB is reliable, sensitive, inexpensive and rapid.  相似文献   
38.
Low explosives such as smokeless powder, black powder, and black powder substitutes have been used in illicit pipe bombings throughout the United States. Some of the newer black powder substitutes are formulated with ascorbic acid, which gradually decomposes as the powder ages, making it difficult if not impossible for the forensic chemist to identify it by traditional bulk techniques. A sensitive method for the identification of residual levels of ascorbic acid in black powder substitutes is presented. Powder samples are extracted with a mixture of acetonitrile and bis(trimethylsilyl)acetamide (BSA), which converts carboxylic acid and alcohol functional groups to trimethylsilyl esters and ethers, respectively. Samples are then analyzed by gas chromatography-mass spectrometry (GC-MS). Results have shown that trace amounts of ascorbic acid can be identified at detection limits that are well below those for traditional bulk techniques. Degradation products for ascorbic acid (hydroxylated carboxylic acids, furanones, and lactones) can also be detected.  相似文献   
39.
40.
A controlled laboratory experiment is described, in principle and practice, which can be used for the of determination the rate of tissue decomposition in soil. By way of example, an experiment was conducted to determine the effect of temperature (12 degrees, 22 degrees C) on the aerobic decomposition of skeletal muscle tissue (Organic Texel x Suffolk lamb (Ovis aries)) in a sandy loam soil. Measurements of decomposition processes included muscle tissue mass loss, microbial CO2 respiration, and muscle tissue carbon (C) and nitrogen (N). Muscle tissue mass loss at 22 degrees C always was greater than at 12 degrees C (p < 0.001). Microbial respiration was greater in samples incubated at 22 degrees C for the initial 21 days of burial (p < 0.01). All buried muscle tissue samples demonstrated changes in C and N content at the end of the experiment. A significant correlation (p < 0.001) was demonstrated between the loss of muscle tissue-derived C (Ct) and microbially-respired C (Cm) demonstrating CO2 respiration may be used to predict mass loss and hence biodegradation. In this experiment Q10 (12 degrees C-22 degrees C) = 2.0. This method is recommended as a useful tool in determing the effect of environmental variables on the rate of decomposition of various tissues and associated materials.  相似文献   
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