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51.
The use of ortho- and para-phenylenediamine (OPD & PPD respectively) for the enhancement of fingerprints in blood has been investigated. Optimal pH conditions and H2O2 concentrations have been determined using UV/Vis spectroscopy. Both OPD and PPD are effective and less hazardous alternatives to the presently used 3,3'-diaminobenzidine (DAB) for the development of blood fingerprints, especially on porous surfaces. The orange color of OPD and the purple color of PPD offer alternative colors to the brown color of DAB and the light green color of ABTS for standing out against particular backgrounds. Both OPD and PPD can be used after ninhydrin treatment, but the reverse is not the case.  相似文献   
52.
Much of the literature on welfare dynamics has focused on the effects of recipient characteristics and state‐level characteristics such as welfare benefits and economic conditions; there has been very little analysis on the effects of child support. This paper, using the 1979‐1996 National Longitudinal Survey of Youth, examines whether child support affects the likelihood of leaving and re‐entering welfare. The results indicate that strong child support enforcement is important in helping young mothers exit and stay off welfare. Women with $1000 child support payments in the previous year were 18 percent more likely to exit welfare and 12 percent less likely to re‐enter welfare. Compared with women in states that pursued child support least vigorously, women in states that had passed extensive child support enforcement legislation and that spent more money on child support enforcement were 79 percent more likely to exit welfare and about 60 percent less likely to re‐enter welfare. © 2002 by the Association for Public Policy Analysis and Management.  相似文献   
53.
The purpose of the present investigation was to test the accuracy of a new scoring system in recording tooth wear for age estimation. The material consisted of dental stone casts of 383 volunteers who had sound premolars and molars with normal occlusion. The degree of occlusal wear for all premolar and molar teeth was scored with the new system. The high intra- and inter-examiner concordances showed that the new score system was very reliable. The degree of tooth wear showed a significant positive correlation with age in each and every examined tooth of both males and females. Tooth wear scores of males were higher than those of females. Calculating tables for age estimation were designed and the accuracy of age estimation was obtained with the General Linear Models procedures. Our system could provide estimation of an individual's age within +/-3 years in 42.4% of males and 49.4% of females, within +/-5 years in 61.8% of males and 63.3% of females. When the subjects were divided into two age groups and data were re-treated, the accuracy of age estimation was increased. Collectively, it was shown that our new system for scoring tooth wear is a reliable and accurate method for age estimation.  相似文献   
54.
An accurate and simple method was developed to determine the level of toluene in urine and blood quantitatively by using the gas chromatography/mass spectrometry (GC/MS) with headspace--solid phase microextraction (HS-SPME) technique. An assembly of SPME with a replaceable extraction fiber, coated with 100 microm polydimethylsiloxane, was used. The detection limit of toluene in blood and urine with HS-SPME technique was 10 times higher than that with headspace (HS) technique. To compare the HS-SPME with HS technique for the determination of toluene in biological fluids, blood and urine samples from glue sniffers were analyzed by both methods. The level of toluene by the two techniques was highly correlated: the correlation coefficient (r2) between the two sets of values were 0.98 and 0.96 in urine and blood, respectively.  相似文献   
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Asphyxia, not an uncommon cause of sudden death, may result from numerous etiologies. Foreign-body aspiration and strangulation are 2 extrinsic causes. Airway obstruction may also be caused by laryngeal edema, asthma, infection, or anaphylaxis. Chronic causes of asphyxia include musculoskeletal diseases (eg, muscular dystrophy, amyotrophic lateral sclerosis), neurologic disorders (eg, myasthenia gravis, multiple sclerosis), respiratory disease (eg, emphysema, chronic bronchitis), or tumors. The manner of death in cases of asphyxiation may be natural, accidental, homicide, or suicide. For the death investigator, determining the cause and manner of death can often be quite challenging.We report here 2 cases of an esophageal fibrovascular polyp causing sudden asphyxial death, review of the literature, and discussion of other differential diagnoses in the case of asphyxial death.  相似文献   
58.
Hypertrophic cardiomyopathy (HCM) is a disease process which results in a large, heavy heart, with hypertrophy of the interventricular septum (IVS) and left ventricle. HCM accounts for a significant number of cases of sudden cardiac death each year, most infamously in young athletes. The prevalence of the disease has increased over the past several years due to advances in clinical diagnosis and molecular genetic studies. Over this same period, new forms of treatment also have emerged. One such treatment is alcohol septal ablation (ASA). ASA is a procedure performed by a cardiologist, via cardiac catheterization, by injecting pure ethanol into selected arteries which supply the IVS, resulting in a targeted myocardial infarction. This infarct then retracts and forms a scar, decreasing the outflow obstruction and improving the patient's clinical symptoms.The authors report 2 cases of death following ASA treatment of HCM. The first, a 56-year-old male, had his ASA procedure 10 days prior to death. The second decedent, a 76-year-old female, had her procedure only 30 hours before death. These case reports are followed by a discussion about HCM, including pathology, treatments, and treatment-related pathology, before closing with a discussion about death certification in the cases presented and therapy-related deaths in general.  相似文献   
59.
This study was designed to compare the qualitative results and concentrations of methamphetamine (MA) and its metabolite amphetamine (AP) in head hair and hair collected from different parts of the body (axillae and pubis). Hair from subjects (N = 14) suspected MA users was simultaneously collected. Hair preparation involved washing step, fine cutting, overnight extraction, derivatization by the trifluoroacetic anhydride, and gas chromatography/mass spectrometry (GC/MS) using selective ion monitoring. In this study, we found a good correlation of the qualitative results for MA between head hair and hair on other parts of the body, but there were some differences in concentrations of MA and AP. Namely, the concentrations of MA and AP were higher in axillary and pubic hair than in head hair.  相似文献   
60.
In this study, 12 Y-specific STR loci--DYS391, DYS389 I, DYS439, DYS389 II, DYS438, DYS437, DYS19, DYS392, DYS393, DYS390, DYS385a/b--were analyzed in 259 unrelated males from the southern populations in Korea using the PowerPlex Y PCR system.  相似文献   
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