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101.
This case study involves the unexplained death of a previously healthy 30‐month‐old child. Reportedly, she was found unresponsive by her foster father following a 2‐hour nap. She was transported to the hospital and died in the emergency room of unknown causes. Blood drawn in the ER showed hemoglobin of 4.3 mg/dL. Postmortem skeletal survey, magnetic resonance imaging (MRI) of the brain, and retinal examinations were negative. The medical examiner assumed jurisdiction of the body. The autopsy showed massive retroperitoneal hemorrhage, transections of the abdominal aorta, and inferior vena cava, and complete tears of the anterior longitudinal ligament of the spine at C5/C6 and L1/L2 with diastases of the vertebral bodies at the corresponding intervertebral disk spaces. The case is believed to be extraordinary due to both the extent of injury that does not match the reported history and the mechanism of vertebral and vascular injuries. 相似文献
102.
103.
Marie-Eve Le Bouthillier MEng Lynne Hrynkiw BASc Alain Beauchamp PhD Luc Duong PhD Sylvie Ratté PhD 《Journal of forensic sciences》2023,68(6):1958-1971
This paper explores a deep-learning approach to evaluate the position of circular delimiters in cartridge case images. These delimiters define two regions of interest (ROI), corresponding to the breech face and the firing pin impressions, and are placed manually or by an image-processing algorithm. This positioning bears a significant impact on the performance of the image-matching algorithms for firearm identification, and an automated evaluation method would be beneficial to any computerized system. Our contribution consists in optimizing and training U-Net segmentation models from digital images of cartridge cases, intending to locate ROIs automatically. For the experiments, we used high-resolution 2D images from 1195 samples of cartridge cases fired by different 9MM firearms. Our results show that the segmentation models, trained on augmented data sets, exhibit a performance of 95.6% IoU (Intersection over Union) and 99.3% DC (Dice Coefficient) with a loss of 0.014 for the breech face images; and a performance of 95.9% IoU and 99.5% DC with a loss of 0.011 for the firing pin images. We observed that the natural shapes of predicted circles reduce the performance of segmentation models compared with perfect circles on ground truth masks suggesting that our method provide a more accurate segmentation of the real ROI shape. In practice, we believe that these results could be useful for firearms identification. In future work, the predictions may be used to evaluate the quality of delimiters on specimens in a database, or they could determine the region of interest on a cartridge case image. 相似文献
104.
Siva Sai Kumar P MBBS Devendra Jadav MD Seshagiri Raju Vempalli MD Vikas P. Meshram MD Tanuj Kanchan MD 《Journal of forensic sciences》2023,68(3):1073-1076
Angle grinders are one of the most dangerous and frequently used tools in industrial settings. Angle grinder injuries range from superficial cuts to deep penetrating injuries with underlying fracture-dislocation and vascular trauma. The injuries caused by angle grinders mostly involve the head, face, or upper limbs, while the lower limb is an unusual site. The high-speed rotating disc of the angle grinders does not respect anatomical boundaries or structures; therefore, the injuries caused may be disfiguring, permanently incapacitating, or even fatal. We report a fatal case of an angle grinder injury to the lower limb. The victim sustained a sharp cut over the left thigh while woodworking in an industrial setup. The rotating disc of an angle grinder had transected the skin, subcutaneous fat and muscles, and both the femoral vessels of the left side, which led to fatal exsanguination within 10 min of the incident. 相似文献
105.
Eleven deaths from crocodile attacks in the Northern Territory, Australia were reviewed. The male:female ratio was 8:3; age range—10–62 years, average 29.4 years. Four children were included (one boy and three girls, aged 10, 11, and two at 12 years), and there were seven aboriginal victims (64%). The attacks were witnessed in eight cases with the victims swimming in freshwater N = 5, standing on a river bank N = 1, fishing in fresh water N = 1, or diving in the sea N = 1. At autopsy, several distinct patterns of injury were observed ranging from complete traumatic disruption of the body with only incomplete remains for examination (N = 5), to crushing of the head with fractures of the skull (N = 4), crushing of the chest with fractures of the ribs and sternum (N = 2), and avulsion of limbs (N = 4). In one case, there was decapitation. Autopsy evaluations were complicated by decomposition and loss of body parts. 相似文献
106.
目的探讨致命室性快速型心律失常(LVTA)能量代谢相关变化及氧化损伤。方法建立以乌头碱(ACO)注射和冠脉结扎(CAL)心肌缺血诱导的LVTA-心脏性猝死(SCD)SD大鼠模型,以过度麻醉(PI)及冠脉结扎心衰致死(CAL-B)为各自对照,检测心室肌线粒体膜电位(MMP)、活性氧(ROS)、丙二醛(MDA)、磷酸肌酸(PCr)及血清肌钙蛋白I(cTnI)含量,并进行比较。结果成功制备ACO-LVTA及CAL-LVTA大鼠14只及6只。与各自的同行对照比较,ACO-LVTA组及CAL-LVTA组心室肌的ROS及MDA呈升高的趋势,PCr呈下降的趋势,其中CAL-LTVA的MDA显著高于其同行对照(P0.05)。ACO-LVTA组心室肌的MMP低于对照组,但高于CAL处理的两组。CAL-LVTA组血清cTnI高于对照组,且显著高于ACO-LVTA组及其对照与处理前(P0.01),ACO-LVTA组血清cTnI高于对照组与处理前。心肌ROS水平与VT及VF持续时间相关(P0.05),相关系数分别为0.44、0.46。结论发生LVTA后,心室肌MMP及PCr下降、ROS、MDA升高,血清cTnI升高,表明LVTA可导致能量代谢改变及氧化损伤,可能与线粒体功能异常相关。 相似文献
107.
108.
目的研究大鼠脑损伤后脑组织中促红细胞生成素(erythropoietin,EPO)及其受体(erythropoietin receptor,EPOR)的表达与损伤时间的关系。方法 72只SD大鼠随机分为对照组(36只)、脑损伤组(36只),在建模后1、2、4、8、12、24 h每组各取6只大鼠处死,取挫伤部位脑组织,应用实时荧光定量PCR和Western印迹法检测不同时间点EPO以及EPOR的mRNA表达和蛋白表达情况。结果伤后24h内,EPO及EPOR的表达随损伤时间的增加而呈上升趋势。EPO的mRNA及蛋白表达与损伤时间之间存在相关性,其相关系数分别为0.875、0.911(P0.05);EPOR的mRNA及蛋白表达与损伤时间之间存在相关性,其相关系数分别为0.936、0.905(P0.05)。结论大鼠颅脑损伤早期EPO及EPOR的表达呈逐步上升趋势,与损伤时间具有相关性,可以作为脑损伤时间推断的参考。 相似文献
109.
目的研究急性肾缺血再灌注损伤早期的差异基因表达,探索其潜在的分子机制。方法通过单纯夹闭大鼠肾动脉制备肾缺血再灌注模型,进行基因表达芯片检测和生物信息学分析,筛选急性肾损伤早期的差异基因表达及其所涉及的细胞活动和信号通路。同时,通过构建差异表达基因的生物网络来寻找与急性肾损伤关系密切的分子,并进行荧光定量PCR验证。结果在检测出的151个差异表达基因中,132个基因显著上调,19个基因显著下调,GO与KEGG通路富集分析结果显示主要与细胞增殖、细胞因子介导的信号通路和免疫反应等有关。荧光定量PCR结果显示,与对照组相比,挑选出的3个与急性肾损伤高度相关的基因(ANXA1、PHLDA1、KLF6)在疾病早期具有显著的表达差异,上升倍数与芯片检测出的倍数基本一致。结论本研究揭示了急性肾损伤早期的差异基因表达特征以及所涉及的生物学过程和信号通路,其中ANXA1、PHLDA1、KLF6可能在急性肾损伤的发病机制中起到一定作用。 相似文献
110.
李晓萍 《福建警察学院学报》2016,(3):23-29
《人民警察使用警械和武器条例》规定了警察违法或合法使用武器造成人员伤亡、财产损失时应该承担的法律责任。由于相关规范抽象模糊,以致在司法实践中滋生不少亟待解决的问题,有必要重新探讨警察用枪行为的性质,构建警察枪械致害赔偿案件统一的救济模式。同时,警察用枪合法与否的判断有赖于一套科学、公正的枪案调查制度。经客观、专业的枪案调查,如若警察用枪行为合法则,警察机关应承担国家补偿责任,相应的补偿渠道和补偿标准值得探讨。 相似文献