Porous β-MoC nanoparticle clusters supported on walnut shell powders derived carbon matrix for hydrogen evolution reaction.

Herein, we choose the waste walnut shell as the carbon source, and ammonium heptamolybdate as the molybdenum source to prepare the β-MoC catalyst supported on carbon matrix (MoC@C) by the calcination method for hydrogen evolution reaction (HER). The open pores in the porous MoC nanoparticle clusters can facilitate electrolyte permeation and hydrogen molecules release as well as the carbon matrix can enhance the conductivity. As a result, the optimal MoC exhibits an efficient HER performance, with an overpotential of 140 mV at 10 mA cm and a Tafel slope of 63 mV dec as well as excellent electrochemical stability.

Variation of Electrocardiogram Features Across Sleep Stages in Healthy Controls and in Patients with Sleep Apnea Hypopnea Syndrome.

Sleep apnea hypopnea syndrome (SAHS) is an independent risk factor for various cardiovascular diseases. Electrocardiogram (ECG) features such as the RR, PR, QT, QTc, Tpe intervals and the Tpe/QT, Tpe/QTc ratios are used to predict and study cardiovascular diseases. It is not clear whether regular patterns of PR and Tpe-related features across sleep stages exist in SAHSs or healthy controls nor whether sleep stages affect the short- and long-range influences of respiratory events on ECG indices.

The correlations between electroencephalogram frequency components and restoration of stable breathing from respiratory events in sleep apnea hypopnea syndrome.

The purpose of this study was to explore the ways in which the Electroencephalogram (EEG) and oxygen saturation (SpO) are involved in the progressive respiratory restoration process in patients with sleep apnea hypopnea syndrome (SAHS). Twenty-five SAHS patients were enrolled in the analysis. The respiratory events scored from polysomnography (PSG) recordings were divided into two groups as follows: the events followed by secondary events (SREs), which failed to recover stable breathing and those that spontaneously restored stable ventilation (N-SREs).