ABSTRACT
OBJECTIVE: The abdominal aorta is a continuation of the thoracic aorta and gives off coeliac trunk, superior mesenteric artery & inferior mesenteric artery. The focus of our study is to evaluate variations in origin level in coeliac trunk, Superior Mesenteric artery, Inferior Mesenteric artery, and Aortic bifurcation in the Indian population and compare with various demographics. MATERIALS AND METHODS: The study was retrospective and the local ethics committee approval was taken before starting it. 300 patients who were of more than 18 years of age and required CECT studies were included in this. The vertebral origin level of the arteries from Abdominal Aorta and Aortic Bifurcation level was analyzed. RESULTS: The most common origin level of Coeliac trunk for both males and females was T12-L1 Disc level. The most common origin level of Superior Mesenteric Artery was L1 Upper level. The most common origin level of Inferior Mesenteric Artery was L3 Upper level. The most common origin level of Superior Mesenteric Artery was L5 Lower level. There was no statistical difference between the origin of any arteries in Males and Females in the Indian Population. CONCLUSION: As per our study in the Indian population and the published literature it is realized that there are significant variations in origins of Coeliac Trunk, Superior Mesenteric artery, Inferior Mesenteric artery and Abdominal Aorta bifurcation in different populations. ADVANCES IN KNOWLEDGE: This study elaborates on potential Anatomical Variations in Indian Population, particularly Mumbai City population. Also, our study compares it to different countries' data and their results in variations found in Abdominal Aorta branches.
ABSTRACT
Mobility and environmental benefits of Green Light Optimal Speed Advisory (GLOSA) systems have been reported by many previous research studies, however, there is insufficient knowledge on the safety implications of such an application. For safe deployment of GLOSA system, it is most critical to identify and address potential safety issues in the design process. It can be argued that implementation of GLOSA system can improve safety by reducing traffic conflicts associated with the interrupted traffic flow at signalised intersections. However, more research findings are needed from field and simulation based studies to evaluate the impacts on safety under a variety of real-world scenarios. As part of the LEVITATE (Societal Level Impacts of Connected and Automated Vehicles) project under European Union's Horizon 2020 Programme, the main objective of this study is to examine the safety impacts of GLOSA under mixed traffic compositions with varying market penetration rates (MPR) of connected and automated vehicles (CAVs). A calibrated and validated microsimulation model (developed in Aimsun) of the greater Manchester area was used for this study where three signalised intersections in a corridor were identified for implementing GLOSA system. An improved algorithm was developed by identifying the potential issues/limitations in some of the GLOSA algorithms found in literature. Behaviours of CAVs were modelled based on the findings of a comprehensive literature review. Safety analysis was performed through processing the simulated vehicular trajectories in the surrogate safety assessment model (SSAM) by the Federal Highway Administration (FHWA). The surrogate safety assessment results showed small improvement in safety with the GLOSA implementation at multiple intersections in the test network only at low MPR (20%) scenarios of CAVs, as compared to the respective without GLOSA scenarios. No or rather slightly lower improvement in safety was observed with GLOSA implementation under mixed fleet scenarios with 40 % or higher 1st Generation or 2nd Generation CAVs, as compared to the respective scenarios without GLOSA. The implementation of GLOSA system was also found to have some impact on the traffic conflict types (although not consistent across all MPR scenarios), where rear-end conflicts were found to decrease while a slight increase was observed in lane-change conflicts.
