Performance of low temperature Microbial Fuel Cells (MFCs) catalyzed by mixed bacterial consortia.

Microbial Fuel Cells (MFCs) are a promising technology for treating wastewater in a sustainable manner. In potential applications, low temperatures substantially reduce MFC performance. To better understand the effect of temperature and particularly how bioanodes respond to changes in temperature, we investigated the current generation of mixed-culture and pure-culture MFCs at two low temperatures, 10°C and 5°C. The results implied that the mixed-culture MFC sustainably performed better than the pure-culture (Shewanella) MFC at 10°C, but the electrogenic activity of anodic bacteria was substantially reduced at the lower temperature of 5°C. At 10°C, the maximum output voltage generated with the mixed-culture was 540-560mV, which was 10%-15% higher than that of Shewanella MFCs. The maximum power density reached 465.3±5.8mW/m2 for the mixed-culture at 10°C, while only 68.7±3.7mW/m2 was achieved with the pure-culture. It was shown that the anodic biofilm of the mixed-culture MFC had a lower overpotential and resistance than the pure-culture MFC. Phylogenetic analysis disclosed the prevalence of Geobacter and Pseudomonas rather than Shewanella in the mixed-culture anodic biofilm, which mitigated the increase of resistance or overpotential at low temperatures.

Influence of a custom-made maxillary mouthguard on gas exchange parameters during incremental exercise in amateur road cyclists.

Mouthguards are frequently used for protection purposes, particularly by athletes competing in contact sports. However, there is increasing evidence supporting their use for improving performance. Studies have focused their use in athletes who do not traditionally use mouthguards and who may be looking for a performance edge. The aim of the current study was to evaluate the influence of a custom-made mouthguard (Parabite Malpezzi, PM) on maximal and submaximal physiological parameters related to performance in road cycling. Ten well-trained amateur road cyclists (34 ± 6 years) performed an incremental cardiopulmonary exercise test to exhaustion on a frictional braked cycle ergometer. Work rate (WR), heart rate, oxygen consumption ((Equation is included in full-text article.)), carbon dioxide production, and ventilation at the lactate threshold, at the respiratory compensation point (RCP), and at maximal exercise (MAX) were determined in normal conditions (C) and wearing PM. Cycling economy was also evaluated by analyzing the slope of the (Equation is included in full-text article.)/WR (Δ(Equation is included in full-text article.)/ΔWR, in milliliters per watt per minute) relationship during the test. Wearing the PM compared with C resulted in significant increases in WR at RCP (281 ± 32 vs. 266 ± 19 W, p = 0.04) and at MAX (353 ± 44 vs. 339 ± 38 W, p = 0.004). The PM also resulted in an average 8% lower Δ(Equation is included in full-text article.)/ΔWR (9.5 ± 1.1 vs. 10.3 ± 1.1 ml·W·min, p = 0.06) but did not significantly modify any of the other measured parameters at LT, RCP and MAX. To the best of our knowledge, this study is the first to evaluate the effects of a dentistry-designed mouthguard on physical performance of road cyclists. These results provide support for cyclists to correct jaw posture that may improve their exercise performance.