Selenium determination in mother and child's hair by electrothermal atomic absorption spectrometry

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.     

The use of supercritical fluid extraction for the determination of amphetamines in hair

A laboratory study interested in the analysis of human hair for drugs-of-abuse was conducted to determine if drugs could be detected and quantified from hair. Supercritical fluid extraction (SFE) techniques followed by GC-MS analysis were applied to extract amphetamines from hair. The group of amphetamines included methylenedioxyamphetamine (MDA), methylenedioxymetamphetamine (MDMA), methylenedioxyethylamphetamine (MDEA) and internal standard mephentermine (MP). To validate information on amphetamine use in hair, powdered hair samples free from drugs were collected and soaked in a known amphetamine standard solution. Authentic fortified case hair samples taken from known drug users known to have consumed amphetamines were also analyzed for amphetamine. Results from this study show that amphetamine use can be detected in spiked and authentic fortified human hair using SFE techniques for qualitative and quantitative reproducible results.     

A biomechanical study of the human vertebral artery with implications for fatal arterial injury

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.     

Computer-assisted facial image identification system using a 3-D physiognomic range finder

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.     

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.     

Beyond traditional paternity and identification cases. Selecting the most probable pedigree

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.     

Unusual infant death: dog attack or postmortem mutilation after child abuse?

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.     

Plastic bag asphyxia in southeast Scotland

Death resulting from plastic bag asphyxia has been recognized for >40 years, but relatively little is known about either its epidemiology or its pathophysiology. Over 15 years (1984-1998), 30 deaths were attributed to plastic bag asphyxia among the 14,560 autopsies performed in the Forensic Medicine Unit in Edinburgh. These 30 deaths involved 20 male and 10 female subjects, with an age range of 13 to 81 years. Eleven had some alcohol measurable in the blood, with four having levels >80 mg/dl. Only one individual appeared to have ingested a drug overdose, but inhaled substances within the plastic bag may have contributed to death in five cases. The absence of childhood accidental deaths may reflect successful preventive measures. The 3 accidental deaths involved adults (including 2 who died of autoerotic asphyxia), and the remaining deaths were 27 suicides. Of those who committed suicide, most (59%) had chronic psychiatric illness rather than chronic debilitating or terminal physical illness. In contrast with reports from the United States, publicity associated with "self-deliverance" did not result in an increased number of deaths from plastic bag asphyxia (4 deaths in this series). Analysis of the circumstances of all the deaths revealed them to be difficult to predict and hence prevent.     

The transfer of petrol on to clothing and shoes while pouring petrol around a room

This study was aimed at measuring the approximate amount of petrol transferred on to the clothing and shoes of a person during the action of pouring petrol around a room. Two different heights of pouring and two different types of floor surface (carpet and concrete) were investigated. Results show that for all the combinations examined petrol was always transferred to the shoes and often transferred to the upper and lower clothing. This information illustrates the necessity of analysing the clothing and particularly the shoes of any suspected arsonists for the presence of hydrocarbon fuels.     

Analysis of eight STR loci in two Hungarian populations

A collection of eight STR loci (D3S1358, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820) was used to generate allele frequency databases for two Hungarian population samples, Caucasians from the Budapest area and Romanies from Baranya county. During the analysis two intermediate sized alleles and a sequence variant allele were observed at the D7S820 locus. All three types of allelic variants were found to have modification (deletion, insertion, transversion) in the same block of a (T)(9) stretch located within the 3' flanking region of each allele, which may indicate a possible higher mutation rate of this (T)(9) block. For the loci D3S1358 and D7S820 the Romany population database showed departures from Hardy-Weinberg equilibrium. The forensic efficiency values for the Romany population were slightly different from those found in the Hungarian Caucasian population. Comparing the allele frequency values by G-statistic, calculating the F(st) indices and with the pairwise comparisons of inter-population variance, the two Hungarian populations could be distinguished using data of the eight STR loci.