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981.
Ninhydrin developed fingerprints can be enhanced by treatment with a zinc or cadmium salt. The resulting fingerprint luminescence has been attributed to the induced coplanarity of the bicyclic indanedione rings of Ruhemann's purple due to complexation with the metal ions. This paper explores whether this effect also occurs in the 1,8-diaza-9-fluorenone (DFO)-amino acid adduct (1), formed from the reaction of DFO with amino acids. Molecular modeling studies of (1) indicate a relatively small out-of-plane angle of 24 degrees. 1H NMR studies indicate (1) is asymmetric about the C2 axis in contrast to what has been previously reported. Little, if any, enhancement of luminescence was observed with Zn, Cd, Ru or Eu treated DFO developed latent fingerprints. This lack of enhancement was also borne out by solution luminescence studies. Given this lack of enhancement of luminescence, solutions of (1) and the four metal ions above were analyzed by electrospray mass spectrometry (ESMS). This indicated the formation of predominantly 1:1 complexes of (1) with both Zn and Cd, and the 2:1 complex with ruthenium. No evidence of a Eu complex was found by ESMS.  相似文献   
982.
983.
984.
Allele frequencies for the 13 STR core loci (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, CSF1PO, TPOX, THO1 and D16S539) included in the AmpFlSTR((R)) Profiler Plus and AmpFlSTR((R)) Cofiler kits were obtained for a sample of 700-800 genetically unrelated Brazilians. The expected performance of these loci for personal identification and paternity testing in the Brazilian population was estimated.  相似文献   
985.
1-Aryl-piperazine compounds are, depending on their substituents, selective for certain serotonin receptors and together with their easy availability and their so-called legal status, this group of psychoactive compounds are potential designer drugs-of-abuse. Internet in that respect is an important source of information and distribution facilities. Because this development may have consequences for the interpretation of future clinical and forensic toxicological case studies, some analytical aspects of 1-benzyl-piperazine (BZP), 1-[4-methoxyphenyl]-piperazine (pMeOPP) and 1-[3-trifluoromethylphenyl]-piperazine (TFMPP) were studied. BZP was not detected by the AxSYM FPIA technology designed to determine amphetamine-like compounds, but had showed some cross reactivity with EMIT d.a.u.. The cross reactivities at 300 and 12,000ng/ml (RS)-amphetamine equivalents were 0.4 and 1.3%, respectively. Although BZP was not identified directly by the REMEDi HS Drug Profiling System, it can be detected by this HPLC/UV scanning system. Using GC/NPD without derivatisation, BZP, pMeOPP and TFMPP can be analysed for and applying GC/MS without or with acetylation or trifluoroacetylation, these compounds can be identified unambiguously. The usefulness of GC/NPD and GC/MS in this respect was demonstrated by the quantitative and qualitative analysis of the content of a capsule with the synthetic stimulant A2, which proved to contain 86.4mg of BZP.  相似文献   
986.
In sexual assault cases, lubricant trace evidence may supplement biological evidence, or may be the primary physical evidence where biological evidence is unavailable. This study considered a total of 50 lubricants from condoms and personal lubricant products available in Australia. Differentiation of the samples was attempted using fluorescence examination, Fourier transform infrared spectroscopy (DRIFTS), gas chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry, and pyrolysis gas chromatography-mass spectrometry. Eleven of the samples were uniquely identified by the analysis scheme, while the remainder of the samples were separated into nine groups. As a result of this study, a recommended protocol for the detection and analysis of an "unknown" biological swab was produced.  相似文献   
987.
988.
挤压综合征大鼠血清酶浓度变化的初步研究   总被引:1,自引:1,他引:0  
Liu SP  Chen YC  Guo W  Cheng JD 《法医学杂志》2001,17(4):205-206
目的观察挤压伤大鼠血清肌酸激酶(CK)、肌酸激酶心肌同功酶(CK-MB)浓度的变化,阐明肢体挤压伤大鼠早期是否存在心脏损伤。方法复制挤压伤大鼠动物模型,全自动生化分析仪检测血清CK、CK-MB浓度的变化。结果挤压伤后12h,血清CK、CK-MB浓度显著升高,并持续48h以上。结论肢体挤压伤早期可能有心脏损伤的存在。  相似文献   
989.
In many countries, including the United States, the number of persons being awarded long-term or permanent disability benefits has risen dramatically in recent years. Government agencies, advocates for the disabled, and others are looking for ways to help persons with disabilities return to the labor force. The Work Incapacity and Reintegration (WIR) Study was developed to address that issue. The United States and five other countries--Germany, Denmark, Sweden, Israel, and the Netherlands--have participated in a cross-national study of work incapacity under the auspices of the International Social Security Association. The study had two objectives: to examine the factors that influence the pattern of work resumption among persons disabled by a back condition and to identify the medical and nonmedical interventions that are most effective in helping such persons reenter the labor force. Samples for the U.S. national study were drawn from four cohorts: Social Security Disability Insurance (DI) beneficiaries, Supplemental Security Income (SSI) beneficiaries, and recipients of temporary disability insurance (TDI) benefits from the states of California and New Jersey. Only the TDI recipients were included in the comparative study. This article discusses the study design and methodology and summarizes the findings of the U.S. national study. Findings from the U.S. study show significant differences between the two cohorts in terms of work resumption and other characteristics. The proportions of respondents from the TDI cohorts who were working at the third and final study contact ranged from 53 percent to 65 percent, compared with less than 5 percent of the DI and SSI respondents. Respondents from the DI and SSI cohorts were on average about 10 years older than the TDI respondents, were less well educated, and reported more physical demands in their usual work. They also reported lower levels of functional capacity, higher levels of pain, and a much greater tendency to have other chronic illnesses. The types of medical treatments provided were remarkably uniform across cohorts and, within cohorts, between those who did and did not resume working. Thus, no medical intervention was identified that showed a significantly higher success rate in terms of facilitating a return to work. However, changes made in the work environment by the employer were an important factor in work reintegration; about 80 percent of respondents who resumed working did so with the help of workplace accommodations. In addition, since respondents with fewer physical demands in their job were more likely to return to work, there appears to be some potential for job retraining as a means of promoting a return to work. The Social Security Administration should consider these findings in developing strategies to help disabled workers reenter the labor force.  相似文献   
990.
This article analyzes the impact of policy variables--employer accommodations, state Social Security Disability Insurance (DI) allowance rates, and DI benefits--on the timing of an application for DI benefits by workers with a work-limiting health condition starting when their health condition first begins to bother them. The analysis uses a rich mixture of personal and employer characteristics from the Health and Retirement Study linked to Social Security administrative records. We find that most workers do not apply immediately for DI benefits when they are first bothered by a health condition. On the contrary, the median working-age man with a work-limiting condition waits 7 years after that time before applying, and the median working-age woman waits 8 years. Although the risk of applying for benefits is greatest in the year following onset, only 16 percent of men and 13 percent of women in our sample apply within the first year, and the risk of application falls thereafter. That finding suggests that institutional factors, in addition to health factors, may play a role in the timing of DI applications. Using kernel density estimates of the distribution of application and nonapplication ordered by state allowance rates (the rate of acceptance per DI determination in each state), we find that both men and women who live in states with high allowance rates are disproportionately more likely to apply for benefits in the first year after their condition begins to bother them than are those in states with low allowance rates. Using life-table analysis, we also find that men and women who are accommodated by their employers are significantly less likely to apply for DI benefits in each of the first few years after their condition begins to bother them than are those who are not accommodated. On the basis of this evidence, we include these policy variables in a model of the timing of DI application that controls for other socioeconomic variables as well as health. Using a hazard model, we find that workers who live in states with higher allowance rates apply for DI benefits significantly sooner than those living in states with lower allowance rates following the onset of a work-limiting health condition. Workers who are accommodated following the onset of a work-limiting health condition, however, are significantly slower to apply for DI benefits. Using the mean values of all explanatory variables, we estimate the relative importance of changes in these policy variables on the speed with which workers apply for benefits after onset. We find that the mean time until application for men is 10.22 years. Universal accommodations following onset would delay application by 4.36 years. In contrast, a 20 percent decrease in state allowance rates would delay application by only 0.88 years. For working-age women, the average expected time until application once a condition begins to bother them is 10.58 years. Universal accommodations would delay that by 3.76 years, and a 20 percent decrease in allowance rates would delay it by 1.47 years. A complication in this analysis is that the policy variables are to some degree endogenous. Accommodation is probably offered more often to workers who want to continue working. Allowance rates are chosen by states on the basis of federal policy and local choices and probably in part on the health condition of workers in the state. Therefore, our estimates are upper bounds of these policy effects. Still, we believe we provide evidence that the social environment faced by workers with work-limiting health conditions can significantly influence their decision to apply for DI benefits, holding their specific health conditions constant.  相似文献   
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