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531.
532.
533.
Fingernail specimens with adherent nail-bed were taken from autopsy material with blood groups A, AB, B and O. Frozen 4-5-microns sections were submerged and floated carefully during each working step. Portions of fingernails were contaminated with blood and buccal cells, respectively. Furthermore, fingernail fragments of 8 volunteers were embedded in a biocomponent adhesive according to Grieve and Kotowski (Forensic Sci. Soc., 26 29-34) (1986) and cut by the usual microtome technique. APAAP staining is a proper method for demonstrating blood group antigens in fingernails from groove to margin. Frozen sections as well as smallest specimen embedded in a suitable adhesive are applicable for staining procedures. Using freshly prepared artificial stains, blood group constellations of red blood cells and/or buccal cells adherent on the surface of fingernails may be distinguished from the nail matrix.  相似文献   
534.
In order to create and study wound morphology, a "skin-skull-brain model" had to be designed which would make the laboratory reproduction of a real ballistic injury possible.To simulate the human skin, an artificial skin (a silicon cap) is used. This silicon scalp contains synthetic fibers (artificial leather) to simulate the collagen and fat of the scalp. The artificial skull is a layered polyurethane sphere (19 cm o.d.; and 5, 6, or 7 mm thick) constructed in a specially designed form with a Tabula externa, Tabula interna, and a porous Diploe sandwiched in between. The periostium of the artificial skull is made of latex. This elastic latex layer prevents the bone fragments from scattering after the model has been struck by gunfire. The brain itself is simulated with ordnance gelatin, 10% at 4 degrees C, a material well known in wound ballistics. Gunshots were fired at a distance of 10 m from the model.During the evaluation of the "skin-skull-brain model", it was possible to show that injuries inflicted to this model are fully comparable to the morphology of equivalent real gunshot injuries.Using the "skin-skull-brain model" has some significant advantages: the model is inexpensive, easy to construct, instantly available for use, and eliminates ethics conflicts. The main advantage of such a model is, in comparison with biological substances, the high reproducibility of inflicted traumas.  相似文献   
535.
The goal of this study was to document the dynamic effects created within, and the developing mechanisms of a gunshot entrance wound to the skin utilizing high-speed photography and the "skin-skull-brain model". The high-speed photography was taken with an Imacon 468/Hadland-Photonics camera. Full metal jacketed, 9 mm Luger projectiles were fired at the target model from a distance of 10 m. During the evaluation of the "skin-skull-brain model", it was possible to show that injuries inflicted to this model are fully comparable to the morphology of equivalent real gunshot entrance wounds. It has been possible to document and study the dynamic process of the "bullet-skin-interaction" in the gunshot entrance wound. The development of the morphologic terms of the entrance wound are discussed. In combination with high-speed photography, this "skin-skull-brain model" is a perfect tool for the documentation and the study of the dynamic development of gunshot entrance wounds in the skin.  相似文献   
536.
This rulemaking controls the chemical N-phenethyl-4-piperidone (NPP) as a List I chemical under the Controlled Substances Act (CSA) (21 U.S.C. 801 et seq.). Clandestine laboratories are using this chemical to illicitly manufacture the schedule II controlled substance fentanyl. The recent distribution of illicitly manufactured fentanyl has caused an unprecedented outbreak of hundreds of suspected fentanyl-related overdoses, at least 972 confirmed fentanyl-related deaths, and 162 suspected fentanyl-related deaths occurring mostly in Delaware, Illinois, Maryland, Michigan, Missouri, New Jersey, and Pennsylvania. NPP has been identified as the starting material in several seized fentanyl clandestine laboratories. In addition to DEA's concern regarding the deaths associated with illicitly manufactured fentanyl, DEA is extremely concerned about the safety of law enforcement officers encountering these clandestine laboratories. Therefore, DEA is regulating NPP as a List I chemical through this Interim Rulemaking. DEA is soliciting comments on this Interim Rule. This rulemaking will subject handlers of NPP to the chemical regulatory provisions of the CSA and its implementing regulations, including 21 CFR Parts 1309, 1310, 1313, and 1316. This rulemaking does not establish a threshold for domestic and international transactions of NPP. As such, all transactions involving NPP, regardless of size, shall be regulated. This rulemaking also specifies that chemical mixtures containing NPP will not be exempt from regulatory requirements at any concentration. Therefore, all transactions of chemical mixtures containing any quantity of NPP will be regulated and will be subject to control under the CSA.  相似文献   
537.
We have analyzed the two hypervariable regions HVS-I and HVS-II of 200 Finnish male individuals for forensic purposes. The distribution of the haplotypes within Finland was determined by the geographical knowledge of the donors' maternal ancestors. In our population sample, we identified 135 different mtDNA haplotypes. Different mtDNA sequences were further divided to haplogroups using the EMPOP software. The most common haplogroups were H (40.0%) and U (27.5%). Subgroup U5b, which contains earlier described "Saami motif", consisted majority (65.5%) of the sample in the U haplogroup. Analysis of the mtDNA sequence hypervariable regions I and II showed that the mtDNA diversity within the Finnish population sample was comparable to other European populations and uniformly distributed. This is contrary to the Y-STR "minimal haplotype" diversity, which in Finland is lower than in any of the other European populations studied so far.  相似文献   
538.
Forensic medical findings have been analysed retrospectively for 242 deceased of acute blood loss: 186 (76.8%) corpses were male and 56 (23.2%) corpses were female. It was found that in acute blood loss (ABL) duration of the terminal period (TP) depended on its combination with craniocerebral trauma (CCT) or alcohol intoxication (AI). A short TP (several minutes) was observed in ABL patients with CCT (39.6%), a long-term TP--in ABL associated with AI (20-60 min, 40.4% cases; several hours, 56.3%; over 24 hours, 54.5%). Slow TP occurred primarily in mild AI (TP for several hours 55.6%, over 24 hours--83.3% cases). In severe AI the number of cases with a short TP exceeded the number of cases with a long TP (over 24 hours) by 53.7%.  相似文献   
539.
This study investigated the relationship between chronological age and pulp tooth area ratio (PTR) in maxillary central teeth using cone‐beam computed tomography (CBCT) images in the Turkish population. The sample consisted of CBCT images of 120 male and female subjects between 14 and 75 years old. The PTR of the maxillary central teeth was calculated using inVivo 5 software (Anatomage, San Jose, CA). Data were analyzed with independent t‐test and Pearson's rank correlation test. There was a significant negative correlation between chronological age and PTR (r = ?0.615). The results showed that the PTR of maxillary central teeth is a reliable method for age estimation in the Turkish population.  相似文献   
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