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Blunt vertebral artery injury occurs frequently in forensic practice. However, injuries of the vertebral artery are easily ignored or overlooked because of its relatively deep location. Through literatures review, this paper finds that the manners of blunt vertebral artery injury are varied and one or more injury mechanisms may be involved simultaneously. Patients often undergo immediate or delayed cerebral apoplexy as well as compression and injury of surrounding structures, due to direct injury or secondary aneurysm or dissection, resulting in disability or death. Diseases such as, vertebral atherosclerosis and dysplasia can increase the disability and death risk and the difficulty of forensic identification. In forensic identification, the details of the case should be considered. For cases of suspected vertebral artery injury, in addition to routine examination of intracranial segment, attention should be paid to the examination of extracranial segment. If conditions permit, angiography can be used prior to or during the autopsy to improve the identification efficiency and accuracy of opinions.

In the realm of ballistic target analysis, micro-motion attributes, such as warhead precession, nutation, and decoy oscillations, play a pivotal role. This paper addresses these critical aspects by introducing an advanced analytical model for assessing the Doppler power spectra of convex quadric revolution bodies during precession. Our model is instrumental in calculating the Doppler shifts pertinent to both precession and swing cones. Additionally, it extends to delineate the Doppler power spectra for configurations involving cones and sphere–cone combinations. A key aspect of our study is the exploration of the effects exerted by geometric parameters and observation angles on the Doppler spectra, offering a comparative perspective of various micro-motion forms. The simulations distinctly demonstrate how different micro-motion patterns of a cone influence the Doppler power spectra and underscore the significance of geometric parameters and observational angles in shaping these spectra. This research not only contributes to enhancing LIDAR target identification methodologies but also lays a groundwork for future explorations into complex micro-motions like nutation. [ABSTRACT FROM AUTHOR]

A modified optimal velocity with dynamical safety headway is introduced based on the optimal velocity car-following model. The dynamical safety headway relates to vehicle's velocity compared to the constant safety headway. To study the influence of dynamical safety headway on the car-following performance, theoretical analysis and numerical simulation of the optimal velocity car-following model with dynamical safety headway are carried out. With the stability analysis method in control theory, a linear stability condition is obtained for the new model. In addition, the car-following performances of traffic flow evolution rules, traffic capacity properties and vehicle starting features of the new model are exhibited through numerical simulation. The results show that the dynamical safety headway is more efficient than the constant safety headway in improving traffic stability, enhancing traffic capacity and shortening the vehicle starting time in the car-following process. It concludes that the dynamical safety headway is a better strategy compared to constant safety headway in real car-following control. [ABSTRACT FROM AUTHOR]

Background: Stanford type B aortic dissection (TB‐AD) is a life‐threatening vascular condition with high rates of morbidity and mortality. Currently, thoracic endovascular aortic repair (TEVAR) is widely performed to treat TB‐AD, and some studies have analyzed the influence of stents on hemodynamics using computational fluid dynamics (CFD) models. However, the accuracy of TB‐AD simulation models are not satisfactory, they are often constructed as a regular ideal model. Furthermore, it is unclear which tear should be closed for the best treatment when there are multi entry tears. Purpose: The aims of this paper were to provide an assessment method for the selection of the surgical closure location for type B aortic dissection. Five 3D models of multiple entry tears in type B aortic dissection were produced using real patient computed tomography (CT) images to perform hemodynamic analyses of flow velocity streamlines, wall pressure, and wall shear stress. Methods: A Boolean operation was adopted to establish 3D models with multiple entry tears in type B aortic dissection based on patient‐specific CT images. The Mimics and Ansys plug‐in The Integrated Computer Engineering and Manufacturing code for Computational Fluid Dynamics (ICEM CFD) software were applied to mesh the 3D models. The flow velocity streamlines, wall pressures, and wall shear stresses were then analyzed in the finite element analysis software Fluent. Five 3D models were produced to compare the hemodynamic characteristics of different entry tear numbers, as well as the changes of different closure positions before and after closure. Results: The false lumen of the model with two entry tears had a higher wall pressure than that of model with multiple entry tears, which may tend to squeeze the true lumen and expand the false lumen. The load distribution of the vessel in the model with multiple entry tears had a more balanced flow velocity, and its wall pressure and shear stress were lower than that of model with two entry tears. For aortic dissection with two entry tears, the closure of the proximal entry tear was recommended, which helped to isolate and thrombose the false lumen, thereby improving the blood supply function of the true lumen. Because the postoperative vascular flow velocity and mechanical load performance of the vascular wall were still higher than those of normal blood vessels, the postoperative blood vessels remained pathological, and TEVAR did not restore the blood vessels to their original healthy state. Conclusions: Type B aortic dissection with two entry tears tend to squeeze the true lumen and expand the false lumen, resulting in a new entry tear and deterioration into multiple entry type B aortic dissection. The model of the vessel with multiple entry tears had a more balanced distribution in flow velocity and a smaller wall pressure and shear stress than that of the vessel with two entry tears. The closure of the proximal entry tear was considered an ideal solution for type B aortic dissection with two entry tears. [ABSTRACT FROM AUTHOR]

Internal carotid arterial system is the main source of blood supply in brain. In forensic identification practice, blunt injures of internal carotid arterial system usually cause complications such as thrombus, aneurysm and arteriovenous fistula, etc. The deaths following delayed cerebral infarction or intracranial haemorrhage are not rare. At present, literature of deaths caused by blunt injuries of internal carotid arterial system mainly consist of case reports in China. This paper reviews related literature and case reports at home and abroad, and summarizes forensic medical features and identification method of the deaths caused by such injuries. The results show that blunt injures of internal carotid arterial system are related to the direct or indirect force on head and neck, which can result in exceed physiological range traction of head and neck, incision following basicranial fracture, etc. Such injuries are common in the cases as mechanical asphyxia, cervical manipulation, traffic accident and fall, etc. The artery should be examined carefully, and the relationship among injury, disease and death should be analysed correctly when no cause of infarction and hemorrhage was found in routine examination of such cases in forensic pratice. Because of the difficulty for exposing the artery completely in autopsy, angiography can be used to infer the location when necessary for improving the scientificity and reliability of the appraisal conclusion.