Increased sample asymmetry and memory of cardiac time-series following endotoxin administration in cirrhotic rats

Sepsis, and other causes of acute systemic inflammation, can reduce heart rate variability (HRV) and increase cardiac cycle regularity in mammals. Thus, HRV monitoring has been used for early detection of sepsis in adults and neonates. Liver cirrhosis is associated with reduced basal HRV and the development of tolerance to the cardiac chronotropic effects of bacterial endotoxin. This may pose limitations on the use of heart rate monitoring in early detection of sepsis in this patient population. In a study to develop a physiomarker for the detection of sepsis in cirrhosis, we observed that endotoxin administration in adult cirrhotic rats leads to the development of transient heart rate decelerations, a phenomenon which has been reported in neonates with sepsis, and quantified using sample asymmetry analysis. In the present study, cirrhosis was induced by surgical ligation of the bile duct in rats. Cirrhotic rats were given intraperitoneal injections of either saline or endotoxin (1 mg kg(-1)). Changes in sample asymmetry and memory length of cardiac time-series were studied in conscious rats using implanted telemetric probes. Cirrhotic (but not control) rats exhibited increased sample asymmetry following endotoxin injection, which was consistent with the development of transient heart rate deceleration. Endotoxin administration in cirrhotic rats was associated with prolongation of memory length for observing decelerating perturbations in the cardiac rhythm. These findings may have application in the development of an HRV monitoring system for early detection of sepsis in cirrhosis

Body temperature fluctuation analysis in cirrhosis

We recently reported that patients with cirrhosis exhibit an abnormal pattern in their skin temperature variability, with complexity analysis of skin temperature fluctuations distinguishing inpatients from outpatients, despite similar mean temperature values [1]. Patients with cirrhosis also exhibit abnormalities in circadian rhythmicity, part of which are of central origin [2]. Therefore, we wondered if abnormalities in skin temperature fluctuations may reflect abnormalities in core body temperature (CBT) regulation in these patients. To test this hypothesis, we analysed CBT data that we had previously recorded in control rats and rats with cirrhosis [3]. This article is protected by copyright. All rights reserved

Risks and Challenges of Adopting Electric Vehicles in Smart Cities

Oil prices and increased carbon emissions are two of the key issues affecting mainstream transportation globally. Hence, EVs (Electric VehiclesElectric Vehicles) are becoming popular as they do not depend on oil, and the GHG (Greenhouse Gases) do not contribute to GHG emissions. In fact, their integration with smart grids makes them even more attractive. Although EVEV adoption is becoming widespread, three groups of challenges need to be addressed. These challenges are associated with EV technology adoption, integration of EVs and smart grids, and the supply chain of EV raw materials. Regarding the EV technology adoption, the risks and challenges include EV battery capacity, drivers’ range anxiety, the impact of auxiliary loads, EV drivers’ behavior, EV owners’ unwillingness to participate in the V2GV2G (Vehicle-to-Grid) program, economic barriers to adopting EVs, difficult EV maintenance, EV performance mismatch between the lab and the real world, need for government regulation, lack of charging infrastructure such as not enough charging stations, and expensive batteries. There are additional challenges concerning the integration with the smart grids such as system overload, high-cost investment in V2G technology, load mismatchLoad mismatch, and unmanaged recharging of EV batteries. Finally, there are challenges regarding the consistent supply of the raw materials needed for EVs. This chapter examines these risks and challenges, suggests solutions and provides recommendations for future research