Volume 25, Issue 2, 2021
Non-alcoholic fatty liver disease is projected to be the most common cause of liver failure in the coming decade and is a very common reason for liver transplantation. One measure of its severity is the level of hepatic fibrosis, traditionally assessed by a liver biopsy. The non-alcoholic fatty liver disease fibrosis score was developed to non-invasively predict the degree of fibrosis using patient characteristics and laboratory values. We hypothesized that this score could also be used to assess the quality of donated livers, since many donors are obese and thus have a higher risk of fatty liver disease. Using data from the United Network for Organ Sharing over two decades, this study tests whether graft failure is associated with the donor liver’s non-alcoholic fatty liver disease fibrosis score. Statistical analysis yielded that the relationship between the score and time till graft failure is insignificant: A chi-square test of independence between the two gives a p-value of .1311, and a Kaplan-Meier survival analysis yielded a p-value of .2, neither of which were under the significance level of .05. Though the results were not statistically significant, future studies on non-invasive assessments and their use may illuminate possibilities for clinical applications.
The vast capabilities of autonomous underwater vehicles (AUVs)—such as in assisting scientific research, conducting military tasks, and repairing oil pipelines—are limited by high operating costs and the relative inaccessibility of power in the open ocean. Wave powered AUV charging stations may address these issues. With projected increases in usage of AUVs globally in the next five years, AUV charging stations can enable less expensive and longer AUV missions. This paper summarizes the design process and investigates the feasibility of a wave powered, mobile AUV charging station, including the choice of a wave energy converter and AUV docking station as well as the ability to integrate the charging station with an autonomous surface vehicle. The charging station proposed in this paper meets many different commercial, scientific, and defense needs, including continuous power availability, data transmission capabilities, and mobility. It will be positioned as a hub for AUV operations, enabling missions to run autonomously with no support ship. The potential market for this design is very promising, with an estimated $1.64 million market size just for AUV technologies by 2025.
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