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This study was set to investigate the prevalence of problematic internet use (PIU) among college students and the possible factors related to this disorder. About 4400 college students, ranging from freshmen to juniors, from eight different universities in Wuhan, China were surveyed. Young's Diagnostic Questionnaire for Internet Addiction (YDQ) and the Zung Self-rating Depression Scale were used to define PIU and depression accordingly. Data was analysed with "chi-squared" testing and logistic regression. Out of the 3496 participants, 9.58% (male 13.54%, female 4.88%) met the criteria of PIU. Factors such as heavy internet use habits, poor academic achievement, lack of love from the family, etc. were found to be significantly associated with PIU. About 48.51% (1696) of the students were light internet users, who use the internet less than 5 h/week, while 16.36% (572) were heavy users who use it more than 15 h/week, though heavy users were more likely to develop PIU. Also, 25.53% of the students with depression developed PIU, in comparison with 8.91% of PIU among those without depression (p less than 0.001). Being male, frequent internet use, poor academic achievement, poor family atmosphere and lack of love from parents were predictors of PIU among college students. The habit and purpose of using the internet is diverse, which influences the susceptibility of PIU as well. There was a correlation between depression and the development of PIU as well. (Contains 4 tables.)

OBJECTIVE: Growing evidence shows that sarcopenia is more prevalent in patients with type 2 diabetes mellitus (T2DM) than in the normal population. However, currently, data on the relationship between blood glucose fluctuation and sarcopenia in elderly patients with T2DM are still limited. PATIENTS AND METHODS: In this study, 280 patients = 60 years with T2DM were divided into sarcopenic group and non-sarcopenic group, according to the diagnostic criteria of 2019 Asian Working Group for Sarcopenia. They wore MeiQi to acquire the indexes including time in range (TIR), time above range (TAR), time below range (TBR), mean amplitude of glycemic excursion (MAGE), coefficient of Variation (CV), blood glucose standard deviation (SD), largest amplitude of glycemic excursions (LAGE) and mean glucose (MG). The prevalence rate of sarcopenia was statistically analyzed and the different indicators of glucose fluctuation between the two groups were compared. We analyzed the indexes of glucose fluctuation and appendicular skeletal muscle mass index (ASMI), handgrip strength, the time of five times sit to stand test (FTSST) with Spearman's correlation analysis. Logistic regression was used to analyze the influence factors for sarcopenia. RESULTS: The prevalence of sarcopenia was 15.36%. TIR, MG and TAR were correlated with ASMI, handgrip strength, the time of FTSST. MG and TAR were risk factors for sarcopenia, while TIR was the protective factor of sarcopenia. After adjusting mixing factors, logistic regression analysis showed that TIR was an independent protective factor. The result of the Chi-square test showed that the incidence of sarcopenia in different TIR ranges was different: the proportion of patients with sarcopenia was 40.48% (TIR =50%), 20.41% (50%70%). CONCLUSIONS: TIR is associated with sarcopenia in elderly T2DM patients. Furtherly, the incidence rate of sarcopenia decreases with the increase of TIR. [ABSTRACT FROM AUTHOR]

Flutter suppression is an important measure to improve fatigue life and enhance the performance of aircraft in modern aircraft design. In order to design more effective controllers for flutter suppression with high efficiency, an efficient reduced-order framework for active/passive hybrid flutter suppression is proposed. The traditional CFD-based ROMs have been successfully applied to active flutter suppression with high accuracy and efficiency. But, when a structure modification is made such as in aeroelastic tailoring and aeroelastic structural optimisation, the structural model should be updated, and the expensive, time-consuming CFD-based ROMs have to be reconstructed; such a process is impractical for passive flutter suppression. To overcome the realistic challenge, an efficient reduced-order framework for active/passive hybrid flutter suppression is proposed by extending an efficient aeroelastic CFD-based POD/ROM which we have developed. The proposed framework is demonstrated and evaluated using an improved AGARD 445.6 wing model. The results show that the proposed framework can accurately predict the aeroelastic response for active/passive hybrid flutter suppression with high efficiency. It provides a powerful tool for active/passive hybrid flutter suppression, and therefore, is ideally suited to design more effective controllers, and may have the potential to reduce the overall cost of aircraft design. [ABSTRACT FROM AUTHOR]

The intake port of a CA4DD diesel engine was investigated by a computational fluid dynamics (CFD) numerical simulation to enhance the intake swirl and improve the flow characteristics in the engine. The uniform design method was applied to study the influence of guide vanes with different parameters on the intake process at various valve lifts. Nine guide vane models were established and compared to the base model using CATIA™ 3D CAD software. Numerical simulations were conduct with Xflow software based on the lattice Boltzmann method (LBM). The distributions of the streamlines, vorticity, velocity and turbulent intensity in each cylinder were simulated and analyzed. The results show that the influence of the guide vanes on the swirl ratio was greater than 37%, and the flow coefficient was less than 5% compared to the base model. Scheme 5, H7.5-L50-θ20 (guide vane height of 7.5 mm, length of 50 mm and angle of 20°), provided good performance. The flow characteristics of the optimal guide vane model were verified through a steady flow test. When the guide vane aspect ratio and angle were within the ranges of 3.5-6.9 and 12.2°-20.2°, respectively, the swirl ratio had the best effect at maximum valve lift. This study provides a theoretical basis for improving the performance of dual-intake diesel engines. [ABSTRACT FROM AUTHOR]