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971.
A controlled laboratory experiment was conducted in order to investigate the effect of the method of burial (i.e. the presence of coffin and clothing) on the formation of adipocere. This study follows previous studies by the authors who have investigated the effect of physical conditions on the formation of adipocere present in a controlled burial environment. The study utilises infrared spectroscopy to provide a preliminary lipid profile of the remains following a 12 month decomposition period. Inductively coupled plasma-mass spectrometry was employed as a technique for determining the salts of fatty acids present in adipocere. Gas chromatography-mass spectrometry (GC-MS) was used as the confirmatory test for the identification and determination of the chemical composition of adipocere which formed in the controlled burial environments. The results suggest that coffins will retard the rate at which adipocere forms but that clothing enhances its formation. The results concur with previous observations on adipocere formation in burial environments. 相似文献
972.
Validation of a 21-locus autosomal SNP multiplex for forensic identification purposes 总被引:8,自引:0,他引:8
Dixon LA Murray CM Archer EJ Dobbins AE Koumi P Gill P 《Forensic science international》2005,154(1):62-77
A single nucleotide polymorphism (SNP) multiplex has been developed to analyse highly degraded and low copy number (LCN) DNA template, i.e. <100 pg, for scenarios including mass disaster identification. The multiplex consists of 20 autosomal non-coding loci plus Amelogenin for sex determination, amplified in a single tube PCR reaction and visualised on the Applied Biosystems 3100 capillary electrophoresis (CE) system. Allele-specific primers tailed with shared universal tag sequences were designed to speed multiplex design and balance the amplification efficiencies of all loci through the use of a single reverse and two differentially labelled allele denoting forward universal primers. As the multiplex is intended for use with samples too degraded for conventional profiling, a computer program was specifically developed to aid interpretation. Critical factors taken into account by the software include empirically determined extremes of heterozygous imbalance (Hb) and the drop-out threshold (Ht) defined as the maximum peak height of a surviving heterozygous allele, where its partner may have dropped out. The discrimination power of the system is estimated at 1 in 4.5 million, using a White Caucasian population database. Comparisons using artificially degraded samples profiled with both the SNP multiplex and AMPFISTR SGM plus (Applied Biosystems) demonstrated a greater likelihood of obtaining a profile using SNPs for certain sample types. Saliva stains degraded for 147 days generated an 81% complete SNP profile whilst short tandem repeats (STRs) were only 18% complete; similarly blood degraded for 243 days produced full SNP profiles but only 9% with STRs. Reproducibility studies showed concordance between SNP profiles for different sample types, such as blood, saliva, semen and hairs, for the same individual, both within and between different DNA extracts. 相似文献
973.
L'Abbé EN 《Forensic science international》2005,151(2-3):201-206
In the spring of 2003, bush cutters discovered a large grain bag filled with human skeletal remains in a forest in South Africa. Differential taphonomic processes observed on the bones suggested that the individuals had not died at the same time or had decomposed under different circumstances. The remains were sorted using gross morphological techniques which included assessing the number of skeletal elements present, visual pair matching, articulation, process of elimination and taphonomy. Standard techniques were used to estimate age, sex, racial affinity and stature. A minimum number of individuals (MNI) of 10 was established, which included 7 adult males, 1 adult female and 2 juveniles. Trauma was observed on only one individual. Approximately, 80% of the skeletal remains were missing. These various skeletal elements may have been lost by accident, normal taphonomic processes or taken by scavengers. Possible origins for these skeletal remains include removal from a formal grave, found in the veldt or murdered. 相似文献
974.
Sukontason K Sukontason KL Piangjai S Narongchai P Samai W Boonchu N Sripakdee D Ngern-Klun R Siriwattanarungsee S 《Forensic science international》2005,154(2-3):195-199
The morphology of the second and third instars of Chrysomya villeneuvi Patton, a fly species of forensic importance, was presented by use of light microscopy. Both instars were of hairy appearance, bearing elongated tubercles along the abdominal and caudal segments. The anterior spiracle had 13-15 papillae. Minute dark spots were observed to thoroughly cover the tubercle's surface, with 4-6 strong dark tips. Regarding the third instar, the intersegmental spines between the prothorax and mesothorax were heavily pigmented. The posterior spiracle had a thick and heavily pigmented incomplete peritreme. The surface and tip of the tubercles was covered with heavily pigmented sharp spines. The integument of the body was covered with numerous distinct net-like patches. A comparison with another well-known hairy maggot, Chrysomya rufifacies (Macquart), was discussed. 相似文献
975.
976.
Renita?R.?Glaser M.?Lee?Van.?Horn Michael?W.?ArthurEmail author J.?David.?Hawkins Richard?F.?Catalano 《Journal of Quantitative Criminology》2005,21(1):73-102
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed. 相似文献
977.
A large literature points to the abominable condition of American jails. Comparison of national surveys of jail conditions conducted in 1972 and 1978 indicates that what little improvement has occurred is minimal compared to remaining problems. A number of factors have prevented state-set standards from achieving widespread improvement in local jail conditions: high costs, local autonomy and lack of credible threats for forcing compliance. The failure of New York State to implement adequate health standards illustrates the limitations of the standards approach. Other approaches, such as strategies for replacing local jails with regional facilities, deserve the attention of policy researchers. 相似文献
978.
979.
980.