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A large body of evidence exists indicating that autonomic imbalance is characteristic of heart failure, with several parameters of autonomic function associated with adverse clinical outcomes. The aim of this systematic review and meta-analysis was to investigate the effects of exercise training on parameters of autonomic function in patients with heart failure and where possible quantify the size of the effect. We conducted database searches (PubMed, EMBASE and Cochrane Trials Register to 31 March 2017) for exercise-based rehabilitation trials in heart failure; using search terms, exercise training, autonomic function, heart rate recovery, heart rate variability and muscle sympathetic nerve activity. Pooled data indicated a statistically significant increase in heart rate recovery at 1 min (HRR1) in exercise compared to control groups, mean difference 5.90 bpm (95%CI 5.12, 6.69; p < 0.00001). Pooled data also indicated that exercise training improved the short-term heart rate variability (HRV) parameters of root mean square of successive differences between normal heart beats (RMSSD (ms)) [mean difference 10.44 (95%CI 0.60, 20.28, p = 0.04)] and high-frequency normalised units (HFnu) [mean difference 7.72 (95%CI 3.32, 12.12, p = 0.0006), which are predominantly reflective of parasympathetic activity. Analyses also indicated a statistically significant decrease in muscle sympathetic nerve activity (MSNA) bursts/minute (mean difference - 11.09 (95%CI - 16.18, - 6.00; p < 0.0001) and MSNA bursts/100 heart beats (mean difference - 15.44 (95%CI - 20.95, -9.92; p < 0.00001) in exercise groups compared to controls. With improvements in HRR, HRV and MSNA, exercise training appears to facilitate an improvement in parasympathetic tone and reduction in sympathetic activity. [ABSTRACT FROM AUTHOR]

We describe a novel, biomimetic tactile sensing system modeled on the facial whiskers (vibrissae) of animals such as rats and mice. The “BIOTACT Sensor” consists of a conical array of modular, actuated hair-like elements, each instrumented at the base to accurately detect deflections of the shaft by whisker-surface contacts. A notable characteristic of this array is that, like the biological sensory system it mimics, the whiskers are moved back-and-forth (“whisked”) so as to make repeated, brief contacts with surfaces of interest. Furthermore, these movements are feedback-modulated in a manner intended to emulate some of the “active sensing” control strategies observed in whiskered animals. We show that accurate classification of surface texture using data obtained from whisking against three different surfaces is achievable using classifiers based on either naive Bayes or template methods. Notably, the performance of both these approaches to classify textures after training on as few as one or two surface contacts was improved when the whisking motion was controlled using a sensory feedback mechanism. We conclude that active vibrissal sensing could likewise be a useful sensory capacity for autonomous robots. [ABSTRACT FROM PUBLISHER]

Trapped organic compounds (lipids) have been analysed in tubular carbonate concretions and their host sediments in Miocene deep water mudrocks from coastal outcrops in East Coast Basin and Taranaki Basin of North Island, New Zealand. The concretions, including calcitic, dolomitic and mixed mineralogies, have varied morphologies in many cases suggestive of conduits or pipes that channelled the escape of subsurface fluids and/or hydrocarbon gases. The extracted lipids include water column and/or diagenetically-derived alkanes, fatty acids and alcohols as well as specific marker compounds (including archaeal pentamethylicosane (PMI) and archaeol) associated with subsurface anaerobic oxidation of upwardly seeping methane gas (AOM). Strong carbon-13 isotopic depletions (δ13C –75 to –120‰) measured for PMI, archaeol and other AOM-specific marker compounds on three concretion samples support involvement of AOM in generating bicarbonate-rich fluid that was at least partly responsible for cementing the pipe-like concretions and central conduits. Other morphological types appear not to be AOM-related. Sterane and n-alkane parameters indicate low thermal maturity of the extracted organic matter. The molecular and compound specific isotopic organic geochemical evidence that some tubular concretions functioned as methane conduits thus supports an assertion that the tubular concretions represent ‘fossilised’ parts of the subsurface plumbing of biogenic or thermogenic hydrocarbon-fed cold seep systems. [ABSTRACT FROM AUTHOR]