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951.
McLean SA 《Journal of law and medicine》2002,9(4):429-437
Increasingly women are seeking to establish pregnancies using sperm retrieved from their dead or dying partners. This raises a number of issues of a broad nature, but is also of significance in terms of the relationship between regulatory mechanisms and private choices. This article reviews this relationship with specific reference to the United Kingdom position, but also taking account of case law and regulation in Australia, particularly in the State of Victoria. 相似文献
952.
Since the concept of "brain death" was introduced in medical terminology, enough evidence has come to light to show that the concept is based on an unclear and incoherent theory. The "brain death" concept suffers by internal inconsistencies in both the tests-criterion and the criterion-definition relationships. It is also evident that there are residual vegetative functions in "brain dead" patients. Since the content of consciousness is inaccessible in these patients who are in a profound coma, the diagnosis of "brain death" is based on an unproved hypothesis. A critical evaluation of the role and the limitations of the confirmatory tests in the diagnosis of "brain death" is attempted. Finally it is pointed out that a holistic approach to the problem of "brain death" in humans should necessarily include the inspection of the content of consciousness. 相似文献
953.
DuBois JM 《Issues in law & medicine》2002,18(1):21-41
This article offers a philosophical foundation for the Uniform Determination of Death Act as it first examines death per se, and then examines brain death and the non-heart beating donor criteria for determining death. The author suggests that many of the debates over death can be bypassed by changing the terms of the debate: what matters is not whether death is a process or an event, but death as a state. Understanding death as a state allows us to determine death in a functional manner that is compatible with the needs of law and medicine. The second part examines objections that arise from ignoring or rejecting the distinction between killing and letting die and the principle of double effect. By clarifying the lines between life and death, on the one hand, and between intentionally killing and unintentionally hastening death, on the other, the author hopes to restore a sense that the proposals to drop the dead donor rule are radical recommendations to cross lines we have never crossed before. 相似文献
954.
955.
956.
The concentrations of antimony, copper, tin, arsenic, silver, bismuth, and cadmium in lead alloys produced by two smelters and one ammunition manufacturer were determined using inductively coupled plasma-atomic emission spectrometry. These element concentrations were used to measure the variations in composition of lead products that result from various processes involved in the manufacture of lead projectiles. In general, when a pot containing molten lead is used to cast a number of objects, these objects are similar, although not necessarily analytically indistinguishable in their elemental compositions. In each subsequent step in the processing of lead at the smelter and at the ammunition manufacturer, the size of an individual homogeneous melt of lead decreases as more distinct compositions are formed as a result of remelting and mixing of sources, including lead scrap. The ammunition manufacturer in this study produced at least 10 compositionally distinguishable groups of bullet wire in a 19.7-h period. The largest group could potentially be used to produce a maximum of 1.3 million compositionally indistinguishable 40 grain bullets. 相似文献
957.
A consignment of individual packages is thought to contain illegal material, such as drugs, in some or all of the packages. A sample from the consignment is inspected and the quantity of drugs in each package of the sample is measured. It is desired to estimate the total quantity of drugs in the consignment. Sampling variation is present in the original measurements and it is not sufficient just to adjust the sample mean pro rata. An analysis is described which takes account of the uncertainty concerning the proportion of the packages that contain drugs and provides a probabilistic summary of the quantity of drugs in the consignment. In particular, a probabilistic lower bound for the quantity of drugs in the consignment is given, which is dependent on the required standard of proof. This is in contrast to the approach based on confidence intervals which assumes that in the long run, the interval will contain the correct quantity the appropriate proportion of the time, but gives no measure of uncertainty associated with the particular consignment under consideration. 相似文献
958.
Evaluation of laser desorption mass spectrometry and UV accelerated aging of dyes on paper as tools for the evaluation of a questioned document 总被引:1,自引:0,他引:1
Laser desorption mass spectrometry (LDMS) may be used for the detection and identification of dyes found in inks. Naturally-aged and artificially-aged blue and black ballpoint pen inks containing the cationic dye methyl violet were analyzed on paper. The average molecular weight of the dye sample was calculated from LD mass spectral data and plotted versus time. The resulting aging curves demonstrate that, as dye degradation increases, the average molecular weight of the dye decreases. Typical variables involved in ink aging, such as the type of paper and ink formulation, were investigated. Results show that these variables influence the rate of dye degradation. Furthermore, UV accelerated aging has been developed and tested as an alternative to thermal approaches. 相似文献
959.
Comparing skeletal structures between antemortem and postmortem chest radiographs is widely used by forensic specialists from many disciplines to positively identify unknown decedents. However, validity assessments of this method have been fairly limited. This study had three objectives: 1) to quantify the reliability of ante- and postmortem chest radiograph comparison for decedent identification; 2) to identify useful radiologic features supporting decedent identification; and 3) to recognize sources of error in decedent identification related to use of comparative radiographs. A forensic pathologist, a forensic anthropologist, and two radiologists participated in the study. Our results showed that chest radiograph comparisons proved reliable, if basic decedent information was provided, and antemortem and postmortem radiographs were adequately positioned and exposed. A "morphological approach" using normal anatomical structures for comparison may provide the most efficient method for accurate identification. 相似文献
960.
Validation of a 16-locus fluorescent multiplex system 总被引:24,自引:0,他引:24
Krenke BE Tereba A Anderson SJ Buel E Culhane S Finis CJ Tomsey CS Zachetti JM Masibay A Rabbach DR Amiott EA Sprecher CJ 《Journal of forensic sciences》2002,47(4):773-785
STR multiplexes have been indispensable for the efficient genotyping of forensic samples. The PowerPlex 16 System contains the coreCODIS loci, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, THOI, TPOX, vWA, the sex determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E. This multiplex satisfies the locus requirements for most national databases and is the most efficient currently available system due to its single PCR amplification. To provide the groundwork for judicial acceptance, including the publication of primer sequences, and to evaluate laboratory-to-laboratory variation, a developmental validation for casework on this commercially available system was performed in 24 laboratories and produced the following conclusions. Amplification was reliable on a variety of thermal cyclers and product could be analyzed on either an ABI PRISM 310 Genetic Analyzer or an ABI PRISM 377 DNA Sequencer. Genotyping using single source samples was consistent between 0.25 and 2 ng of input DNA template with a few laboratories obtaining complete genotypes at 0.0625 ng. However, heterozygote allele imbalance (<60% peak height balance) caused by stochastic effects was observed at a rate of 13% with 0.125 ng DNA and 22% at 0.0625 ng DNA. Mixture analyses were done using a total of 1 ng of DNA template. Most alleles were detected in mixtures of 4 to 1 and some minor alleles were detected in mixtures of 19 to 1. Optimum amplification cycle number was dependent on the sensitivity of the detection instrument used and could also be adjusted to accommodate larger amounts of DNA on solid supports such as FTA paper. Reaction conditions including volume, annealing temperature, and concentrations of primer, AmpliTaq Gold, and magnesium were shown to be optimal yet robust enough to withstand moderate variations without affecting genotype analysis. Environmental, matrix and standard source analyses revealed an ability to obtain complete genotypes in all sample types except those exposed to 80 degrees C for 12-48 days. Finally, comparison of genotype results from the PowerPlex 16 System with other commercially available systems on non-probative reference and forensic samples showed consistent results. 相似文献