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21.
目的 探讨无骨折脱位型颈脊髓损伤案例中外伤与损害后果因果关系法医学鉴定的要点.方法 收集25例无骨折脱位型颈脊髓损伤的法医学鉴定案例资料,总结被鉴定人的年龄、致伤方式、影像学检查结果、自身颈椎退变情况、临床表现、主要诊疗情况、预后情况等,按照损伤与损害后果相关程度分为直接原因、主要原因、同等原因、次要原因、无原因进行伤... 相似文献
22.
Tetramethylene disulfotetramine (tetramine) is a rodenticide that has been banned for many years in China. Since 2005, inhabitants of a village in the Henan Province have been suffering from grand mal seizures. To investigate the possibility of tetramine as the cause, we developed a method to determine tetramine in human hair. Sample preparation involved external decontamination, frozen pulverization, and ultrasonication in 2 mL ethyl acetate in the presence of cocaine-d3 as an internal standard. The method exhibited good linearity; calibration curve was linear over a range of 0.1-20 ng/mg hair. The limit of detection for the assay was 0.05 ng/mg hair. Except for one subject (No. 4), all head and pubic hair samples were positive for tetramine. The concentrations of tetramine in pubic hair were significantly higher than those in the same subjects' head hair samples. Because of a long retention in body, segmental head hair analysis cannot provide an accurate exposure history of tetramine in the body. 相似文献
23.
Min Li Ruiyang Tao Wei Zhou Yanan Li Meng Meng Yilun Zhang Linsheng Yu Liqin Chen Yingnan Bian Chengtao Li 《法庭科学研究(英文)》2021,6(1):84
Short tandem repeat (STR) profiling is one of the mostly used systems for forensic applications. In certain circumstances, STR profiling is time-consuming and costly, which potentially leads to delays in criminal investigations. LGC (Laboratory of the Government Chemist, UK) Forensics has developed a robust STR profiling platform called the ParaDNA® Intelligence Test System which can provide early tactical intelligence and aid investigators in making informed decisions on sample prioritization for detection. Here, we validated the ParaDNA intelligence test for its application in forensic cases using a range of mock evidence items following guidelines set by the Scientific Working Group on DNA Analysis Methods (SWGDAM). Specifically, we tested the sensitivity and accuracy of the ParaDNA intelligence test, as well as the success rates for detecting mock samples and for use in case scenarios. Our findings demonstrate that the ParaDNA intelligence test generates useful DNA profiles, especially for samples such as blood, saliva, and semen that contain ample DNA, indicating the benefits of including ParaDNA as a prior step in forensic STR profiling pipelines. 相似文献
24.
Darrell O. Ricke Ph.D. Philip Fremont‐Smith M.S. James Watkins B.S. Sara Stankiewicz M.S. Tara Boettcher B.S. Eric Schwoebel Ph.D. 《Journal of forensic sciences》2019,64(5):1468-1474
High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures. 相似文献
25.
Noelia I. Zanetti DB Andrea Costantino DChem Natalia Lazzarini BSChem Adriana A. Ferrero DB Néstor D. Centeno DB 《Journal of forensic sciences》2021,66(1):245-254
Fluoxetine is a selective serotonin reuptake inhibitor, commonly used for the treatment of a variety of psychopathological conditions. As such, fluoxetine may be expected to appear in clinical and forensic cases. Dermestes maculatus De Geer (Coleoptera: Dermestidae) has been recognized as a relevant component of the insect fauna associated with decomposing human and animal remains. Experiments were conducted to study the effect of fluoxetine on developing D. maculatus using two‐drug administration models: a non‐living animal model (pork muscle) and a living one (Sus scrofa L. pigs). We assessed the duration of immature stages and total life cycle, as well as morphological parameters (body length, cephalic width, and weight). The effect of fluoxetine was studied at an overdose concentration: In the non‐living animal model the drug was mixed with macerated pork muscle (2000 mg/kg) and in the living animal model, pigs were given the drug orally (833 mg/kg). A control was used for each model. Daily observations were performed from the beginning to the end of the experiments. GC‐MS was used for drug detection and quantification. There were no statistically significant differences in the duration of immature stages, life cycle, larval mortality, morphological parameters, or sex ratio, between treatment and control, regardless of the drug administration model. Given that fluoxetine had no detectable effect on the development of D. maculatus, detection of this drug in forensic situations would not compromise the accuracy of PMI estimations. 相似文献
26.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.
Key points
- Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
- Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
- These metrological principles also apply to individuation of unique objects in general.
27.
28.
Shivpoojan Kori 《法庭科学研究(英文)》2021,6(1):19-33
Recently, cloud point extraction (CPE) coupled with back extraction (BE) has been suggested as a promising alternative to liquid-liquid extraction. In CPE, non-ionic surfactants in aqueous solutions form micelles and the solution becomes turbid when heated to the cloud point temperature. Microwave- or ultrasonic-assisted BE can be performed after CPE and before injection of the sample for instrumental analysis by ultraviolet-visible spectroscopy, high-performance liquid chromatography, gas chromatography, gas chromatography-mass spectrometry, or liquid chromatography-mass spectrometry. This article reviews selected published scientific research on the application of CPE-BE to the determination of alkaloids, drugs and organophosphorus compounds from several complex matrices. This method could be scaled-up for use in forensic science. 相似文献
29.
Claudine Abegg Ilaria Balbo Alejandro Dominguez Silke Grabherr Lorenzo Campana Negahnaz Moghaddam 《法庭科学研究(英文)》2021,6(1):34-41
Virtual anthropology (VA) is based on applying anthropological methods currently used to analyse bones to 3D models of human remains. While great advances have been made in this endeavour in the past decade, several interrogations concerning how reliable these models are and what their proper use should be remain unanswered. In this research, a fundamental assumption of VA has been investigated: if the way we perceive and apply an anthropological method is truly similar when looking at bones macroscopically and through various 3D media. In order to answer, 10 skulls of known age and sex were scanned using a computed tomography (CT) scanner and a 3D surface scanner. Two observers separately applied a defined staging method to eight suture sites on these skulls, first looking at the bone macroscopically, then at the 3D surface scan, and finally on the CT scan. Two rounds of observation were carried out by each observer. Intra- and inter-observer error were evaluated, and two sample t-tests used to evaluate if the different types of medium used yielded significantly different observations. The results show a high degree of inter-observer error, and that data obtained from 3D surface scans differ from macroscopic observation (confidence level 95%, P ≤ 0.05). CT scans, in these settings, yielded results comparable to those obtained through macroscopic observations. These results offer many possibilities for future research, including indications on the kind of anthropological methods and anatomical landmarks that might be reliably transferable to the virtual environment. All current methods used in traditional anthropology should be tested, and if they prove unreliable, new techniques to analyse bones from virtual models should be developed.
Key points
- Large discrepancies between observation on dry bones and computer-generated 3D models (surface scans or CT scans) could lead to the re-evaluation of the suitability of traditional anthropological methods for application on 3D models.
- This preliminary study evaluates whether macroscopic, 3D surface scans, and CT scans viewings generate different observations.
- The results indicate that the data are not always coherent across all three media of observation.
- Explanations include the aspect given to the bone by the 3D software, differences between handling bones in real life versus on a computer, and level of expertise of the observers.
30.