300 publications from this institution
This paper focuses on analyzing the variation of stress in real exam scenarios. We collected ECG data from 35 college students during an exam, divided the stress physiological data into three segments, i.e. early, middle and late durations of an exam, and used machine learning methods to built binary classification models of each pair of the above three exam durations, and obtained the best F1 scores of 84.21 %, 66.67% and 73.68%, respectively. Statistical test results showed that subjects had stronger stress levels during the early duration of the stressful exam than during the middle and late durations.
The investigation of indigenous wine yeast can facilitate the production of distinctive Beijing wine by providing wineries with more choices in distinctive wine yeasts. Wine yeasts that were isolated from grape must during spontaneous fermentation and from vineyard soil were preliminarily classified by their colony morphologies when cultured on Wallerstein Laboratory Nutrient (WLN) medium and then were identified by 5.8S ITS sequence analysis. Four selected strains were involved in inoculated fermentation tests. The results showed that five yeast species were isolated from the grape must, and five non‐ Saccharomyces yeast species were found in vineyard soil. The colony morphology of Pichia occidentalis on the WLN medium was described herein for the first time. An effective way which could be used for isolate and select wine yeasts from soil samples on WLN medium was described. And one of the selected indigenous strains shared over 99% similarity on 5.8S ITS sequence with commercial wine yeast, which indicated that commercial yeast might have influenced the local yeast diversity. The two selected indigenous Saccharomyces cerevisiae strains, which showed good fermentation performances, could be applied in the local wine industry in the future.
This study focuses on the static output feedback control of nonlinear Markov jump singularly perturbed systems within the framework of Takagi–Sugeno fuzzy approximation. From a practical point of view, the phenomenon of asynchronous switching between the plant and the controller is considered and characterized by a finite piecewise‐homogenous Markov process. Particularly, for facilitating the controller synthesis, the closed‐loop system is transformed into a fuzzy Markov jump singularly perturbed descriptor system by adopting descriptor representation. In order to fully accommodate the system features, an appropriate stochastic Lyapunov function is constructed. Afterwards, by combining Finsler’s lemma, the mean square exponential admissibility of the system is analyzed. The conditions ensuring the existence of the predesigned controller are given and further solved by designing a brief search algorithm. Finally, a typical circuit system is used to demonstrate the application potential of the developed control technology and the effectiveness of the control strategy.
This article explored the effect of physical activity time and that of the heart rate during physical activity on mental fatigue intervention. First, we acquired electrocardiogram from 104 subjects, calculated the inter-beat intervals (IBI), removed the abnormal values in the IBI series, segmented and divided the IBI series into training and validation datasets and application datasets according to the inclusion criteria of mental fatigued and non-fatigued states. Second, we extracted 39 linear and non-linear RR parameters as fatigue physiological features, and applied Leave-One-Subject-Out cross test and Sequential Backward Selection algorithm for feature selection while training some traditional classifiers. Third, we applied the best trained classifier to detect mental fatigue before and after physical activity. Finally, we analyzed the change of mental fatigue status before and after physical activity and obtained the following three findings: (1) physical activity did not have intervention effect on mental fatigue for 62% observed cases; (2) for 38% observed cases, physical activity could aggravate or relieve mental fatigue; (3) for the observed cases that the physical activity time was in the range of 5-15 minutes, the average heart rate in 100-140 beat per minute during physical activity was more likely to relieve mental fatigue
The isobaric tags for relative and absolute quantitation (iTRAQ) were applied to identify differentially expressed proteins (DEPs) in Litopenaeus vannamei in response to different virulence white spot syndrome virus infection. A total of 2780 unique peptides corresponding to 754 proteins were identified. The number of significant differentially expressed proteins was 161, including 38 up‐regulated ones and 123 down‐regulated ones in low‐virulence infection library compared with normal‐virulence infection library. Gene Ontology function annotation indicated that the differentially expressed proteins mainly participated in the biological process. Subcellular location classification showed that the largest distribution of differentially expressed proteins was found in the cytoplasm in both down‐regulated and up‐regulated proteins. Kyoto encyclopaedia of genes and genomes analysis revealed that most of the differentially expressed proteins were involved in carbon metabolism. Moreover, three metabolic pathways, including carbon metabolism, inositol phosphate metabolism, and fructose and mannose metabolism, were significantly affected. Our findings offered a better understanding of the host response to different virulence white spot syndrome virus infection. Significance and Impact of the Study: White spot syndrome virus (WSSV) is one of the most harmful pathogens in shrimp farming. Previous studies have shown that genetic variations of white spot syndrome virus cause the strains of different virulence. The hosts also show different self‐regulation when infected by different viruses. A better understanding of host response to white spot syndrome virus will help elucidate the virulence and pathogenesis of this unique pathogen.
How to restrain the recombination of photogenerated electrons and holes is still very important for photocatalytic hydrogen production. Herein, Z-scheme ZnWO4/Mn0.5Cd0.5S (ZWMCS) nanocomposites are prepared and are applied as visible-light driven precious metal cocatalyst free photocatalyst for hydrogen generation. The ZnWO4/Mn0.5Cd0.5S nanocomposites with 30 wt% ZnWO4 (ZWMCS-2) can reach a photocatalytic hydrogen evolution rate of 3.36 mmol g−1 h−1, which is much higher than that of single ZnWO4 (trace) and Mn0.5Cd0.5S (1.96 mmol g−1 h−1). Cycling test reveals that the ZMWCS-2 nanocomposite can maintain stable photocatalytic hydrogen evolution for seven cycles (21 h). The type of heterojunction in the ZWMCS-2 nanocomposite can be identified as Z-scheme heterojunction. The Z-scheme heterojunction can effectively separate the electrons and holes, so that the hydrogen generation activity and stability of the ZWMCS-2 nanocomposite can be enhanced. This work provides a highly efficient and stable Z-scheme heterojunction photocatalyst for hydrogen generation.
