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951.
Gusmão L González-Neira A Sánchez-Diz P Lareu MV Amorim A Carracedo A 《Forensic science international》2000,112(1):49-57
The amplification of the STR DYS391, using the primers described in the Genome Data Base (GDB: G00-365-251), shows not only an additional band to the Y-specific one in males with a size range of 26 bp less than those of DYS391 locus alleles, but also a polymorphic pattern in females in the same size range as the additional band observed in males. The DYS391 pattern in families reflects a Y-specific linked locus and also a polymorphic X locus with an X-linked pattern of inheritance. A first screening in the X homologous locus allowed the identification of five different alleles. Allele frequencies were explored in different population groups for both the Y locus and the homologous locus in the X chromosome showing a similar allele distribution pattern in the X and Y homologous loci. An alternative reverse primer was designed to amplify the Y-chromosome specific STR in order to improve the specificity and applicability of this system to forensic genetics. Comparative results of the amplification with the new and the previously described primers proved that with this new primer there is a substantial increase in the specificity of the amplification. Moreover, a smaller fragment is amplified with a size out of the range of the alleles of the other Y-STRs usually used in forensic applications, therefore simplifying its inclusion in multiplex systems. 相似文献
952.
Tagliaro F Valentini R Manetto G Crivellente F Carli G Marigo M 《Forensic science international》2000,107(1-3):121-128
The present paper describes an integrated diagnostic strategy to check the physical fitness of subjects, formerly users of illicit drugs, to obtain a driving license, after having quit their addiction. According to the Italian law, applicants for a driving license with a history of drug abuse must give evidence to have quit this behaviour and to show no risk of relapse in the future. To prove this, at our institute, they undergo medical examination, hair analysis and a urinalysis program on eight seriate samples, collected over about 40 days. About 700 subjects per year are investigated with this strategy. The hair samples are screened for opiates (morphine), cocaine and ecstasy, the most abused illicit substances in our region, by using commercial radioimmunoassays adopting cut-off levels of 0.1 ng/mg. All positive samples and about 10% of negatives are confirmed by high-performance liquid chromatography. Further confirmation of results can be carried out by capillary electrophoresis (and/or GC/MS or MS/MS). In 1998, the prevalence of positives for morphine, cocaine and ecstasy was 4.8, 11.3 and 2.6%, respectively. In this year, for the first time, the percentage of hair samples positive for cocaine was greater than that for opiates. The results of this integrated diagnostic strategy are presented and discussed, with particular emphasis on the comparison between hair analysis on a single sample and seriate urinalyses (on eight samples). 相似文献
953.
Bermejo Barrera P Lorenzo Alonso MJ Bermejo Barrera A Cocho de Juan JA Fraga Bermúdez JM 《Forensic science international》2000,107(1-3):149-156
A method for the selenium determination in a mother and her child's hair using palladium as a chemical modifier was optimized. The sample was digested with nitric acid and hydrogen peroxide and diluted to 5 ml. To achieve complete mineralization the samples were ashed at 1200 degrees C in the presence of palladium as a chemical modifier. The optimum atomization temperature was 1900 degrees C. The precision and accuracy of the method were studied using the reference material CRM 397. Results of calibration using aqueous standards and the standard addition method were compared. The method was applied to the selenium determination in 30 samples of the mother's and child's hair. The levels found were 0.54 +/- 0.34 microgram/g for mother's hair and 0.77 +/- 0.25 microgram/g for child's hair. 相似文献
954.
Uhl M 《Forensic science international》2000,107(1-3):169-179
The Bavarian State Bureau of Investigation in Munich has the exclusive responsibility for investigation of criminal acts. One considerable expertise is that of hair analysis. According to the legal system in Germany, there is a special interest when some clients' hair tested positive for illicit drugs. An accused with a lot of drugs in his hair will be treated as a supposed addict and will be guaranteed extenuating circumstances. The instrumentation used for hair analysis is a powerful analytical tool: a Varian 3400 gas chromatograph linked to a Finnigan Tandem-MS (TSQ 700). The methanol extraction method is used for the detection of illegal drugs and metabolites: amphetamine, methamphetamine, MDA, MDMA (ecstasy), MDE, MBDB, methadone, THC, EDDP (metabolite of methadone), cocaine, benzoylecgonine, cocaethylene, opiates (dihydrocodeine, codeine, heroin, 6-monoacetylmorphine, morphine, acetylcodeine). For the detection of 9-carboxy-THC by negative chemical ionization the hair sample is hydrolyzed under alkaline conditions. Solid-phase extraction is used for clean-up. The LOQ for the determination of 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic-acid is 0.16 pg/mg hair. An unsurpassed combination for rendering an expert opinion based on hair analysis may be: a forensic expert using diligence and experience, coupled with the performance of a sophisticated analytical instrument. 相似文献
955.
A biomechanical study of the human vertebral artery with implications for fatal arterial injury 总被引:8,自引:0,他引:8
We studied the biomechanical behaviour of ring and strip specimens from along the length of 18 vertebral arteries taken from 16 subjects aged 28-90 years, in order to consider some of the factors which may play a role in vertebral artery rupture. The method was chosen to allow a comparison between circumferential distension (ring samples) and longitudinal extension, (strip samples). The samples were extended between the jaws of a tensile testing apparatus until the specimen broke and a number of biomechanical parameters were derived. These were the percentage extension to break, the tensile strength, Young's modulus and the peak load. There were a number of important findings. The vertebral artery was shown to be susceptible to longitudinal stretching with a number of strip samples breaking when extended by as little as 16-20%. The tensile strength and load at peak of the strip specimens were correspondingly lower than for the ring samples. Marked intersubject variations were shown for all these parameters and prominent changes in behaviour occurred along the vertebral artery. This study indicates that the artery may be susceptible to head and neck movements which cause the vessel to stretch, and intersubject variations in behaviour may be one important explanation for the marked differences in outcome which appear to exist in subjects who suffer broadly similar head and neck insults. 相似文献
956.
Computer-assisted facial image identification system using a 3-D physiognomic range finder 总被引:3,自引:0,他引:3
Yoshino M Matsuda H Kubota S Imaizumi K Miyasaka S 《Forensic science international》2000,109(3):225-237
This system consists of a 3-D physiognomic range finder and a computer-assisted facial image superimposition unit. The 3-D range finder is composed of a detector for measuring facial surface and its control computer. The detector has two sinusoidal grating projection devices and two CCD cameras. The computer-assisted facial image superimposition unit consists of a host computer including a proprietary software, a flat surface color display and a color image scanner for inputting 2-D facial images of a criminal. The 3-D facial shape and texture of a suspect is obtained by using the range finder. To make the comparison between the 3-D facial image and the 2-D facial image, the 3-D facial image is first reproduced on a display of the host computer from a MO disk and then the 2-D facial image is taken with the color image scanner and reproduced on the display. The 3-D facial image is exactly adjusted to match the orientation and size of the 2-D facial image under the fine framework mode, and then the fine framework mode of 3-D facial image is converted to the fine texture image. The shape and positional relationships of facial components between the 3-D and 2-D facial images are examined by the fade-out or wipe image mode. The distance between the selected two points and angle among the selected three points on the 3-D and 2-D facial images are automatically measured for the assessment of anthropometrical data between both images. For evaluating the fit between the anthropometrical points on the 3-D and 2-D facial images, the reciprocal point-to-point difference between both images is compared. 相似文献
957.
The estimation of the age of skin bruises is of importance in forensic medicine, especially in child abuse cases. Time-dependent changes in bruise colour and/or associated histological features have been used with a limited degree of success. An increased rate of apoptosis in the injured tissue has been considered as a novel time-dependent marker of cell death, by injury inflicted in a rat model. The object of the present study was to apply the TUNEL method of DNA end labelling to identify and enumerate apoptotic cells in bruised and normal skin in order to study the relationship of apoptotic cell density with the age of the bruise. A commercially available DNA end labelling kit, TUNEL method, was standardised, validated and used for this purpose. Twenty unselected post-mortem cases with bruises due to a variety of causes were studied. The apoptotic cells stained with TUNEL reaction were counted in 10 high power fields in the epidermis, as well as in the dermis of formaldehyde-fixed paraffin-embedded skin specimens. The mean positive cell densities (+/- 1 S.E.) were compared with respect to the age of the bruise. In the epidermis, the mean apoptotic cell count was statistically significantly greater in the bruised skin compared to normal skin in 2- to 6-day-old bruises; whilst in the dermis the same was true in 3- to 8-day-old bruises. The overall findings suggest that there is a quiescent period prior to the increase in the apoptotic cell activity that is seen following skin bruising. This is so provided the post-mortem skin samples were collected within a lapse of 6 days or less between the time of death and formalin fixation and paraffin embedding to avoid the bias made by the difference of length of post-mortem interval. 相似文献
958.
The paper extends on the traditional methodology used to quantify DNA evidence in paternity or identification cases. By extending we imply that there are more than two alternatives to choose between. In a standard paternity case the two competing explanations H(1): "John Doe is the father of the child and H(2): "A random man is the father of the child, are typically considered. A paternity index of 100000 implies that the data is 100000 more likely assuming hypothesis H(1) rather than H(2). If H(2) is replaced by "A brother of John Doe is the father", the LR may change dramatically. The main topic of this paper is to determine the most probable pedigree given a certain set of data including DNA profiles. In the previous example this corresponds to determining the most likely relation between John Doe and the child. Based on DNA obtained from victims of a fire, bodies found in an ancient grave or from individuals seeking to confirm their anticipated family relations, we would like to determine the most probable pedigree. The approach we present provides the possibility to combine non-DNA evidence, say age of individuals, and DNA profiles. The program familias, obtainable as shareware from http://www.nr.no/familias, delivers the probabilities for the various family constellations. More precisely, the information (if any) prior to DNA is combined with the DNA-profiles in a Bayesian manner to deliver the posterior probabilities. We exemplify using the well published Romanov data where the accepted solution emerges among 4536 possibilities considered. Various other applications based on forensic case work are discussed. In addition we have simulated data to resemble an incest case. Since the true family relation is known in this case, we may evaluate the method. 相似文献
959.
Boglioli LR Taff ML Turkel SJ Taylor JV Peterson CD 《The American journal of forensic medicine and pathology》2000,21(4):389-394
An unusual form of fatal child abuse is reported in which investigations by the police and the medical examiner were able to distinguish blunt force head trauma followed by postmortem dismemberment from a fatal dog attack. A discussion of the approaches used to ascertain the correct diagnosis is presented, as well as an overview of dog attacks on humans. 相似文献
960.