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911.
Roger W. Byard M.D. 《Journal of forensic sciences》2016,61(5):1244-1249
Epistaxis or nosebleed refers to bleeding from the nostrils, nasal cavity, or nasopharynx. Occasional cases may present with torrential lethal hemorrhage. Three cases are reported to demonstrate particular features: Case 1: A 51‐year‐old woman with lethal epistaxis with no obvious bleeding source; Case 2: A 77‐year‐old man with treated nasopharyngeal carcinoma who died from epistaxis arising from a markedly neovascularized tumor bed; Case 3: A 2‐year‐old boy with hemophilia B who died from epistaxis with airway obstruction in addition to gastrointestinal bleeding. Epistaxis may be associated with trauma, tumors, vascular malformations, bleeding diatheses, infections, pregnancy, endometriosis, and a variety of different drugs. Careful dissection of the nasal cavity is required to locate the site of hemorrhage and to identify any predisposing conditions. This may be guided by postmortem computerized tomographic angiography (PCTA). Despite careful dissection, however, a source of bleeding may never be identified. 相似文献
912.
Nicholas R. Maiden Ph.D. Ian Musgrave Ph.D. Wesley Fisk Roger W. Byard M.D. 《Journal of forensic sciences》2016,61(3):679-686
Torso models for ballistics research require that the mechanical properties of simulant materials must match the heterogeneous nature of tissues/organs within the human thorax/abdomen. A series of energy loss experiments were conducted on fresh porcine organs/tissues at room temperature and 37°C, using steel 4.5 mm BBs fired from a Daisy® brand air rifle. They were compared to FBI and NATO specification ordnance gelatin and a candidate surrogate material called Simulant “A”. Two CED M2 chronographs measured BB velocity. The resulting energy loss was established using KE = 1/2 mv² before and after target perforation. The combined results at room temperature and 37°C were as follows: FBI specification gelatin was similar (p > 0.05) to heart and lung, spleen was similar to NATO specification gelatin, Simulant “A” was similar to hindquarter muscle, and hindquarter muscle, kidney, and spleen were similar to each other regarding energy retardation. These results can be used as a basis for the development of simulant materials to create an anatomically correct heterogeneous model. 相似文献
913.
Incidence of Low Body Mass Index in the Elderly in Forensic Cases—A Possible Marker for Frailty Syndrome? 下载免费PDF全文
Diagnosing frailty syndrome at autopsy may be difficult if no adequate clinical history is provided. As low body mass index (BMI) may be associated with frailty in the elderly, the following study was undertaken to determine the percentage of medicolegal cases with BMIs < 18.5 in decedents aged over 75 years. Review was undertaken over three time periods: January to December 1986, January to December 2006, and January to December 2012. In 1986, 16% (15 of 93) of individuals aged ≥75 years had BMIs < 18.5, in 2006, 15% (50 of 336), and in 2012, 13% (35 of 274). In no case was frailty syndrome mentioned. This study demonstrates that frailty syndrome appears to be an underappreciated diagnosis in forensic practice despite a significant percentage of elderly decedents (13–16% over a 27‐year period) having low BMIs. Prospective assessment of this group is required to determine the incidence and contribution to mortality of frailty syndrome in a forensic context. 相似文献
914.
Histological Changes in the Thyroid Gland in Cases of Infant and Early Childhood Asphyxia—A Preliminary Study 下载免费PDF全文
A retrospective blinded study of thyroid gland histology was undertaken in 50 infants and young children aged from 1 to 24 months. Deaths were due to (i) suffocation (N = 7), hanging (4), wedging (3), and chest and/or neck compression (4), and (ii) SIDS (20), noncervical trauma (7), organic disease, (4) and drug toxicity (1). In the asphyxia group (N = 18), thyroid gland congestion ranged from 0 to 3+ with 39% of cases (7/18) having moderate/marked congestion. In three cases, focal aggregates of red blood cells (blood islands) were observed within the intrafollicular colloid. These deaths involved chest compression, chest and/or neck compression, and crush asphyxia in a vehicle accident, and all had facial petechiae. Only 22% of the 32 control cases (7/32) had moderate/marked congestion with no blood islands being identified (p < 0.05). Blood islands within the thyroid gland may be caused by congestion associated with crushing or compression and may provide supportive evidence for this diagnosis. 相似文献
915.
Charles Roger Satishkumar Belliethathan 《International Environmental Agreements: Politics, Law and Economics》2016,16(1):91-108
The African Group of Negotiators (AGN) has become a much more significant bargaining coalition in the global climate change negotiations. It has been participating more proactively and on a much more significant scale, and, as a result, it has had a greater impact on bargaining outcomes, notably in Nairobi, Copenhagen and Durban. Yet, at present, the group remains poorly understood by both scholars and policymakers. Compared to other groups in the climate negotiations, such as the Group of 77 and Alliance of Small Island States, it has received relatively little attention. This paper fills this gap by tracking the evolution of the AGN over the course of the climate change negotiations. In the early years after the Earth Summit, it shows that the AGN faced tremendous difficulties pursing regional objectives effectively, largely due to a number of “internal” barriers to participation, which compounded the structural barriers that the continent faced by making it difficult to use “low-power” negotiating strategies such as coalition building, agenda-setting and persuasion. However, in recent years, the group has become much more proactive as a result of greater access to material, ideational and institutional resources. These have relieved, somewhat, the internal barriers that the group faced, making it possible for the AGN to negotiate much more confidently and effectively than before. 相似文献
916.
917.
Barrett esophagus and unexpected death 总被引:2,自引:0,他引:2
Byard RW 《The American journal of forensic medicine and pathology》2007,28(2):147-149
Barrett esophagus is characterized by the presence of columnar mucosa in the lower esophagus in continuity with gastric mucosa. Complications include ulceration and adenocarcinoma. Although sudden and unexpected death is not a usual outcome, the case of a 63-year-old man is presented who died unexpectedly following perforation of an ulcerated Barrett esophagus, with development of an esophagopleural fistula. Sudden and/or unexpected death in individuals with Barrett esophagus may result from hemorrhage due to erosion into mural vessels, the aorta or heart, or from penetration into the pleural space, trachea, bronchi, and pericardial sac, with the development of tension pyopneumothorax, bronchial fistula, and mediastinitis. Ulceration of the lower esophagus at autopsy should prompt consideration of the possibility of a Barrett esophagus and initiate careful dissection/examination of the surrounding mediastinal tissues and vessels. 相似文献
918.
The application of forensics to wildlife crime investigation routinely involves genetic species identification based on DNA sequence similarity. This work can be hindered by a lack of authenticated reference DNA sequence data resulting in weak matches between evidence and reference samples. The introduction of DNA barcoding has highlighted the expanding use of the mtDNA gene, cytochrome c oxidase I (COI), as a genetic marker for species identification. Here, we assess the COI gene for use in forensic analysis following published human validation guidelines. Validation experiments investigated reproducibility, heteroplasmy, mixed DNA, DNA template concentration, chemical treatments, substrate variation, environmental conditions and thermocycling parameters. Sequence similarity searches using both GenBank BLASTn and BOLD search engines indicated that the COI gene consistently identifies species where authenticated reference sequence data exists. Where misidentification occurred the cause was attributable to either erroneous reference sequences from published data, or lack of primer specificity. Although amplification failure was observed under certain sample treatments, there was no evidence of environmentally induced sequence mutation in those sequences that were generated. A simulated case study compared the performance of COI and cytochrome b mtDNA genes. Findings are discussed in relation to the utility of the COI gene in forensic species identification. 相似文献
919.
The investigation of deaths due to the inhalation of volatile substances may be complicated by a lack of scene and autopsy findings. Mechanisms of death may not be determinable at autopsy, and there may be very few markers of inhalant abuse. A 21-year-old man is reported who died from the combined effects of methadone toxicity and toluene inhalation. Histological examination of the lungs revealed congestion and edema, as well as particles of blue, pigmented material within the interstitium and in macrophages. Scanning electron microscopy was undertaken, revealing that the particles contained granules that measured 0.15-0.2microm in diameter, within the range of mean particle sizes for inorganic paint pigments. Energy dispersive X-ray spectral analysis of the granules demonstrated a significant percentage of titanium (12%) confirming their origin from paint. Ancillary investigations such as electron microscopy and X-ray spectral analysis in cases of possible lethal volatile inhalation may prove useful adjuncts in determining the type of substance inhaled and in providing evidence of previous non-lethal episodes. 相似文献
920.
This article identifies key features of the sociotechnical contexts of computer law and security at the times of this journal's establishment in 1985, and of its 200th Issue in 2018. The infrastructural elements of devices, communications, data and actuator technologies are considered first. Social actors as individuals, and in groups, communities, societies and polities, together with organisations and economies, are then interleaved with those technical elements. This provides a basis for appreciation of the very different challenges that confront us now in comparison with the early years of post-industrialism. 相似文献