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1.
Woollen and acrylic ski masks were used to investigate the persistence of fibres in both Caucasian and negroid head hair. Fibre loss followed an exponential decay with both types of fibre persisting for up to six days if the hair was not washed or up to three days if the hair was washed.  相似文献   

2.
Prehistoric Polynesian skeletal remains are frequently being recovered in New Zealand due to the increasing pace of urbanisation. Since such material must often be reinterred quickly, it is important that the sex of individuals be determined from the remains in a relatively short time. For this purpose, discriminant function analysis was utilised for sex determination of prehistoric adult New Zealand Polynesian femora (47 male and 44 female). Three measurements of the femoral head were taken and subjected to Statistical Package for the Social Sciences (SPSS) discriminant function analysis. For the discriminant functions derived, accuracy of sex determination ranged from 80.9% to 82.4%. Reduction in error over random assignment by sex ranged from 62% to 65%.  相似文献   

3.
In this study, the effects of fibre type, hair style, time and fibre persistence on the secondary transfer of mask fibres to pillowcases via head hair were studied. Volunteers with a range of hair styles, and masks consisting of different fibre compositions were used in the study. Fibres from the masks were found to transfer from donor subjects to the pillowcases up to 14 nights after the mask had been worn. On average, the number of secondarily transferred fibres found decreased with time; however, this decrease appeared to be more 'linear' in nature, rather than an exponential decay. The greatest degree of secondary transfer occurred with cotton, then acrylic, then wool. In a primary transfer/persistence experiment with a 50% acrylic/50% wool mask, wool was found to persist in the hair more readily than acrylic. The results also showed that the greatest degree of secondary transfer occurred via short straight and long straight hair, with no clear pattern emerging between medium length hair (both straight and curly) and with long curly hair. The implications of these findings for the assessment and interpretation of casework are considered along with data obtained from related studies.  相似文献   

4.
Twin populations are ideal for studying human variation; a study of twin's hair, therefore, provided a better understanding of the value of hair comparisons. Duplicate head hair samples from 17 pairs of twins and one set of identical triplets were compared in a verified blind study. In addition to the direct comparison of all twins, random samples of two or three hairs were compared with randomly selected groups of known samples in a second blind study, to better simulate an ordinary forensic science case. Features commonly used by forensic hair examiners were adequate to distinguish hair samples from each twin from all other samples, illustrating the power of microscopical comparison when numerous questioned hairs are available in evidence. When two or three hairs were compared with randomly selected known samples, several were indistinguishable from hair samples other than the true source, proving once again that a human hair can never be associated with one person to the exclusion of all others.  相似文献   

5.
In 2002 a population study of textile fibres in human hair was carried out using 26 volunteers in Cambridgeshire, UK. Over 12,000 fibres were recovered from a variety of hair lengths using low adhesive tape and classified according to colour, generic type and fibre length. The results of the study showed that the most common fibre colours were black/grey (48%), blue (29.1%) and red (12.7%), the least common being green, orange/brown and yellow which each accounted for less than 5% of the total. Natural fibres (mainly cotton) were predominant (72.3%) and man-made fibres were considerably less frequent. When colour and generic type were classified together, the most common combinations were black and blue cottons. The least common were the man-made fibre/colour combinations with the most frequent of these accounting for less than 7% of the sample. Fibre loads carried by long hair were found to be significantly less than that carried by short hair. The results of this study are in accordance with previous fibre population studies using other types of recipient surfaces and are likely to be influenced by factors such as seasonal and geographical variation.  相似文献   

6.
7.
Ethyl glucuronide (EtG) is a minor metabolite of ethanol that can be detected in hair. In some specific situations, head hair can be missing, and therefore, alternative anatomical locations of hair are of interest. In this study, paired hair specimens (head hair and pubic hair) from eight social drinkers were analyzed for EtG. Each sample was decontaminated by two dichloromethane bathes (5 ml) for 2 min. After cutting into small pieces, about 50 mg of hair was incubated in 2 ml water in the presence of 10 ng of EtG-d5, used as internal standard and submitted to ultra-sonication for 2 h. The aqueous phase was extracted by SPE using Oasis MAX columns. The hair extract was separated on an ACQUITY BEH HILIC column using a gradient of acetonitrile and formate buffer. Detection was based on two daughter ions: transitions m/z 221-85 and 75 and m/z 226-75 for EtG and the IS, respectively. This laboratory is using a positive cut-off at 50 pg/mg. All eight head hair specimens were negative for EtG at a limit of quantitation fixed at 10 pg/mg. Surprisingly, EtG was identified at high concentrations in pubic hair, in the range 12-1370 pg/mg. It appears, therefore, that it is not possible to document the drinking status of a subject by simply switching from head hair to pubic hair.  相似文献   

8.
Detection of anabolic steroids in head hair   总被引:1,自引:0,他引:1  
We developed a gas chromatography/mass spectrometry method for detection and quantitation of anabolic steroids in head hair. Following alkaline digestion and solid-phase extraction, the MO-TMS derivatives gave a specific fragmentation pattern with EI ionization. For stanozolol, the TMS-HFBA derivative showed several diagnostic ions. For androstanolone, mestanolone (methylandrostanolone), and oxymetholone two chromatographic peaks for cis and trans isomers of derivatives were seen. Recoveries were 35 to 45% for androstanolone, oxymetholone, chlorotestosterone-acetate, dehydromethyltestosterone, dehydrotestosterone, fluoxymesterone, mestanolone, methyltestosterone, and nandrolone; 52% for mesterolone, trenbolone; 65% for bolasterone; 24% for methenolone and 17% for stanozolol. Limits of detection were 0.002 to 0.05 ng/mg and of quantitation were 0.02 to 0.1 ng/mg. Seven white male steroid abusers provided head hair samples (10 to 63 mg) and urine. In the hair samples, methyltestosterone was detected in two (confirmed in urine); nandrolone in two (also confirmed in urine); dehydromethyltestosterone in four (but not found in urine); and clenbuterol in one (but not in urine). Oxymethalone was found in urine in one, but not in the hair. One abuser had high levels of testosterone: 0.15 ng/mg hair, and 1190 ng/mL urine. We conclude that head hair analysis has considerable potential for the detection and monitoring of steroid abuse.  相似文献   

9.
A woman, who was hospitalized with extensive burns in the genital and perineal region, accused her husband who lived apart from her to have inflicted the injuries with a lighter and a burning candle out of jealousy. The husband denied the accusations and stated that he wanted to singe off the pubic hair with the lighter during sadomasochist sexual practices performed in mutual agreement. As he did so extensive flames suddenly developed--something he had not expected--thus causing the burns. To check the statement cut off tufts of head and pubic hair were set on fire with a lighter to compare their burning behaviour. Pubic hair was easily inflammable and burnt almost completely within about 10 seconds developing up to 10 cm high flames, whereas straight head hair developed only minor flames and the singed hairs stopped burning spontaneously some seconds later already.  相似文献   

10.
Washing hair with shampoo results in an accumulation of shampoo components in the hair. Hair of individuals using different shampoos can be distinguished by analysis of shampoo residues. A method for extraction and analysis of such residues is presented. The hair is extracted using a methanol/water mixture, and the extract is analyzed by reverse-phase high-pressure liquid chromatography (HPLC). The detector system consists of two ultraviolet (UV) detectors connected in series. The method is nondestructive to hair and is sensitive enough to be applied to a single hair 5 to 10 cm in length. Residues from hair balsams are analyzed by this technique as well. The use of this method in forensic science examination of human head hair is demonstrated.  相似文献   

11.
Methadone concentrations in human hair of the head, axillary and pubic hair   总被引:2,自引:0,他引:2  
The concentrations of methadone and its metabolites in the hair of the head, axillary and pubic hair obtained from patients receiving a daily maintenance doses, were determined. Comparison of the concentrations provides the highest values in the axillary hair, followed by pubic hair and the hair of the head.  相似文献   

12.
13.
Xie Y  Yi XF  Chen XG  Lin X  Guo SF  Wang Q 《法医学杂志》2006,22(4):299-300,302
通过对2例颅脑外伤后假性癫痫的法医鉴定案例的分析,总结假性癫痫发作的临床特点及外伤后假性癫痫发作与外伤性癫痫发作的鉴别要点。其法医学鉴定应结合颅脑外伤的程度、部位、颅内有无后遗病灶及临床发作特点等综合分析。  相似文献   

14.
A method for identifying the group appurtenance of biological objects from subjects suffering from various diseases is developed. The method can be used in examination of putrefactive objects (blood, secretions, hair, etc.) and in cases when the group appurtenance cannot be identified by other methods.  相似文献   

15.
Comparative studies of head hair obtained from europeoid and negroid people showed no difference in water and sulfur content, resistance to temperature exposure and alkaline solution as well as in electrophoretic distribution of keratin proteins. At the same time values of rupture loads and extension as well as value of curl elasticity of negroid people's hair surpass substantially the same characteristics of europeoid people's hair.  相似文献   

16.
The use of average curvature measurements for the forensic comparison of curly hairs has been reported, but a method, in which various types of hair form are quantitatively examined and objectively interpreted for hair comparison, has not been reported to date. In the present study, numerical data on hair form from Japanese subjects were obtained by image analysis and a morphological comparison of these head hairs was investigated. Head hairs obtained from eight Japanese males were measured for length (L), distance (D) and area (A) using a Kontron Imaging System KS400. From the three measurements mentioned above, three indexes, L/D, A/D and 2(A/L), were examined. The inter-individual variations for each value were investigated by a t-test and the availability of six values for the forensic comparison of hair form was evaluated by a stepwise linear discrimination analysis. Six values obtained from hair form by an image analysis showed large intra-individual variations. However, these six values were found to be useful for discriminating between two individuals, since the six values showed larger inter-individual variations than intra-individual variations. Discrimination on each comparison using a stepwise linear discrimination analysis was performed for some of the values and the results indicated conspicuous inter-individual variations between the two individuals. On 11 of 28 comparisons, 30 hairs from one individual could be completely distinguished from hairs of another individual, when a two-way comparison was employed. These results confirm that hair form could be quite useful in the forensic comparison of hair morphology, and suggest that numerical data obtained from hair form by image analysis are very important values for constructing a screening procedure for evidential hairs. The use of an objective measure of hair form will be especially useful for Japanese head hairs since they are generally thought to show very limited variation in morphological features.  相似文献   

17.
DNA isolation from hair shafts can involve a number of steps, each of which adds time to the procedure and increases the risk of contamination. A simple alkaline digestion procedure that directly dissolves hairs was developed and compared with a widely used glass grinding/organic extraction method, using samples collected from 30 volunteers with varying population ancestries, hair colors, and hair treatments. A 203 bp mtDNA product could be amplified from 90% of samples extracted by alkaline digestion and 73% of hairs extracted by glass grinding. DNA obtained from alkaline digested hair generated equal or greater amplification success for virtually all criteria examined, and mtDNA sequences matched buccal control sequences in all cases. The two methods were similar in DNA yield (amplification success at template dilution) and quality of DNA obtained (amplicon length). Alkaline digestion of hair shafts required 6-7 h to complete, compared to 22-24 h for glass grinding, and proved a less laborious yet equally robust method for mtDNA extraction.  相似文献   

18.
With increasing urban development in New Zealand, prehistoric Polynesian skeletal remains are frequently being recovered. Since such material must often be reinterred quickly, it has become important that the sex of individuals be determined from the remains in a relatively short time. For this purpose, discriminant function analysis was utilised for sex determination of prehistoric adult New Zealand Polynesian innominates (21 male and 35 female). Maximum diameter of the acetabulum was measured and subjected to SPSS direct discriminant function analysis. Accuracy of sex determination ranged from 85.2% to 86.2%. Reduction in error over random assignment by sex ranged from 70% to 72%. The two discriminant functions derived will provide a useful tool for the assessment of human remains in the forensic and archaeological context because they incorporate a single measurement which can be taken on incomplete bones.  相似文献   

19.
In order to aid the interpretation of hair results from methamphetamine (MA) abusers the MA and amphetamine (AP) concentrations in 2070 hair samples were statistically evaluated. The MA and AP concentrations in hair were put into three groups arbitrarily representing low, medium and high ranges and the metabolite-to-parent drug ratios of each group were examined. The concentration ranges proposed here were also applied to the interpretation of five authentic cases. The low, medium and high ranges of MA were 0.5–4.2, 4.2–24.5 and 24.5–608.9 ng/mg and those of AP were 0.1–0.4, 0.4–1.7 and 1.7–41.4 ng/mg. The AP-to-MA ratios showed large variation but a tendency that it decreased as the MA ranges increased. This evaluation was very useful to presume the severity of individuals’ MA abuse and to provide law enforcement agencies more understandable information. It could also facilitate the court's decision regarding specific circumstances surrounding the drug-related crimes.  相似文献   

20.
Only two types of human hair roots (proximal ends) derived from decomposing scalps are reported in the literature. The most common representation of the putrid root includes a postmortem dark root band in published photomicrographs. In this study, 22 cases were reviewed in which there was reliable time of death documentation from medical investigator reports. A review of these cases finds that the most common putrid hair proximal end change does not contain the postmortem root band. Four primary types of hair proximal end postmortem change were identified. This study finds no correlation of time of death with scalp hair proximal end decomposition. In addition two examples are presented that suggest that hair roots do not decompose after fresh removal from the scalp and exposure to the outside elements.  相似文献   

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