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Background As the most common chronic liver disease, nonalcoholic fatty liver disease (NAFLD) has been reported to be associated with significant changes in myocardial structure and function, but it is still a controversial issue whether it is an independent risk factor for abnormalities in cardiac structure and function. Objective To assess the correlation of NAFLD with early left ventricular diastolic dysfunction by comparing left ventricular structure and functional indices between NAFLD and non-NAFLD patients. Methods A total of 519 inpatients from Geriatric Medicine Unit, Peking University People's Hospital were enrolled during 2018 to 2020, and divided into NAFLD group and non-NAFLD group according to the results of abdominal ultrasound or CT examination. Left ventricular structural and functional indices of two groups were comparatively analyzed. Early left ventricular diastolic dysfunction was defined as the ratio of the peak velocity of the early filling (E) wave to the atrial contraction (A) wave 3.25) 〕. NAFLD patients were divided into low-risk subgroup (n=81) and medium-high risk subgroup (n=100) according to whether FIB-4 index

Through the study on high temperature creep data of HP heat resistant alloy, a prediction method of high temperature creep deformation based on Zc parameter was proposed. The creep resistance of HP heat resistant alloy was predicted by this method. The results indicate that the predicted data are in good agreement with the HP heat resistant alloy creep experimental data at 1000,980℃ and 930℃. At the same time, the creep rupture life of heat resistant alloy was evaluated by this method, the results show that the predicted principal curves agree well with the experimental data.

Based on an as-serviced 25Cr35Ni type steel, the high temperature property evaluation using stress relaxation test(SRT) method and residual life prediction were studied. The results show that creep rupture property decreases because of the formation of network carbides along grain boundaries and coarsening of secondary carbides in the austenitic matrix. Based on the relationship of stress relaxation strain rate curves obtained at different temperatures, and the extrapolation equation of stress relaxation rate-rupture time, it is capable to perform residual life evaluation by combining SRT data and a small amount of creep rupture test(CRT). Good agreement is observed for predicting results performed by current method and traditional method.

The stress relaxation data up to 8760h at 550℃ and 600℃of 12Cr-1Mo-1W-0.25V heat-resistant steel were used as the object to study the method of how to accurately and effectively predict long-term relaxation stress by using short-time relaxation data. When relaxation model is used to extrapolate the long-term relaxation stress directly, it is found that the parameters of the relaxation model depend on the length of the fitted data. The time-dependent parameter model, naming as timing parameter method, is proposed to predict the long-term relaxation stress with high accuracy. By comparison of the results of timing parameter method and direct extrapolation method, timing parameter method has obvious advantages in predicting long time relaxation stress with short time relaxation data, as the timing parameter method has a more accurate prediction than that of direct extrapolation method.

Power of the existing small-sized wind turbine blades is much less than the theoretical value. This study improved 100 W wind turbine blades to increase the power of wind turbine. First of all, Spalart-Allmaras model which was suitable for airfoil stalling characteristics research was used to analyze the aerodynamic characteristics of seagull airfoil and standard airfoil with different angles of attack (AOA). Seagull airfoil and standard airfoil were got from seagull wing and standard blade by portable three-dimension scanner, Imageware software and Geomagic Studio software through standard blade scan, seagull wing scan, point cloud processing, reverse engineering modeling and cross section capture. Lift coefficients and lift-drag ratios of seagull airfoil and standard airfoil were calculated by Fluent software. Secondly, bionic blade was designed based on standard 100 W blades and Glauert theory. Thirdly, numerical simulations of bionic blade and standard blade were performed by using SST(shear stress transport) k-oe model which was suitable for blade performance research to analyze the aerodynamic characteristics of bionic blade and standard blade. Last of all, efficiencies of bionic wind turbine and standard wind turbine were measured by using self-designed test platform to compare the effects of these 2 kinds of wind turbines. Lift coefficient of seagull airfoil was higher than that of standard airfoil with different AOA of from 0 to 20°. The maximum lift coefficient of seagull airfoil was 2.19 times that of standard airfoil with the AOA of 8°. Lift-drag ratio of seagull airfoil was also higher than that of standard airfoil with different AOA of from 0 to 20°. The maximum lift-drag ratio of seagull airfoil with the AOA of 3° was 1.34 times that of standard airfoil with the AOA of 5°. Static pressure color map showed that surface pressure difference of seagull airfoil was larger than that of standard airfoil with the same AOA. With the AOA of 15°, upper surface of standard airfoil was separated with airflow totally, whereas for seagull airfoil there was only half separation. Numerical simulations manifested that static pressure of standard blade was distributed from tip to root, whereas in bionic blade it was from tip to middle. Efficiency tests indicated that power of bionic blade was larger than that of standard blade within the wind speed of 0-10.7 m/s, which increased by 25.77%. The lift coefficient of seagull airfoil was higher than that of standard airfoil, which proved that seagull airfoil provided more lift than standard airfoil under the same working condition. The lift-drag ratio of seagull airfoil was higher than that of standard airfoil, which proved that seagull airfoil provided more power than that of standard airfoil under the same working condition. With the AOA of 15°, airflow was totally separated with standard airfoil but partly separated with seagull airfoil, which proved that stalling AOA of seagull airfoil was larger than that of standard airfoil. Therefore, it can be concluded that aerodynamic characteristics of seagull airfoil are better than that of standard airfoil, and seagull airfoil adapts to more complex working condition. This research provides the reference for improving the design of small-sized wind turbine. [ABSTRACT FROM AUTHOR]

Objective: To compare the time-effect rule of pain-relieving in moderate dysmenorrhea in the treatment between acupuncture on single-point and acupuncture on multi-point so as to determine the best time of needle retaining on single-point and multi-point as well as provide the reference evidences of acupuncture frequency in the treatment., Methods: Sixty-three cases of moderate dysmenorrhea were randomized into a single-point group (31 cases) and a multi-point group (32 cases). During the attack of dysmenorrhea, in single-point group, Shiqizhui (EX-B 8) was punctured; in multi-point group, Shiqizhui (EX-B 8), Diji (SP 8), Ciliao (BL 32) and Sanyinjiao (SP 6) were punctured and the needles were retained for 30 min. Visual Analogue Scale (VAS) values were recorded in the immediate time before acupuncture, in 5 min, 10 min, 20 min and 30 min after needle insertion, as well as in 30 min, 60 min and 120 min after needle withdrawal separately., Results: After needling, analgesia was generated rapidly in either group. During 30 min of needle retaining, analgesia was enhanced persistently till needle withdrawal in either group. In 10 min after needle insertion, the immediate analgesia in multi-point group was superior obviously to single-point group (P < 0.05) and this effect was maintained in 2 h after needle withdrawal. In 30 min after needle withdrawal, acupuncture analgesia was declined to the maximum., Conclusion: Either single-point acupuncture at Shiqizhui (EX-B 8) or multi-point acupuncture at Shiqizhui (EX-B 8) and other acupoints has apparent immediate analgesia on primary dysmenorrhea of moderate degree, but the effect of multi-point acupuncture is better than that of acupuncture at Shiqizhui (EX-B 8). No matter with acupuncture at Shiqizhui (EX-B 8) or at multi-point, the time of needle retaining should not be shorten than 30 min. It is suitable to give acupuncture, twice per day for the patients with moderate and persistent pain.

In the present study, a total of 47 levofloxacin hydrochloride injection samples were detected by near infrared (NIR) spectroscopy, and 37 samples were randomly selected to establish the quantitative models by partial least squares (PLS) and artificial neural network (ANN) technology, while other 12 samples were used for prediction. On the one hand, the model was established by PLS, the coefficient of determination (R2) of the prediction is 0.964, and the root mean squared error of prediction (RMSEP) is 0.2428. On the other hand, after the spectrum variables were highly effectively compressed using the wavelet transformation technology, the quantitative analysis model of levofloxacin hydrochloride was established through the ANN technology. The R2 and RMSEP of the model is 0.944 and 0.5722, respectively. In this work, we have a detailed comparison between the two technologies in the progress of two quantitative models and optimizing correlative parameter, and finally we got a satisfied result. The simulation experiment indicated that the above PLS model is more steady and precise than ANN model, which can get hold of a rapid and nondestructive quantitative analysis result of the injection. Thus, the research can provide powerful scientific basis and technical support for further analysis of levofloxacin hydrochloride injection.

In the present study, 40 samples of ginsengs (20 samples from Jian and 20 samples from Fushun) were surveyed by Fourier transform infrared (IR) spectroscopy. Meanwhile, in order to eliminate the spectral differences from the baseline drifts, the original ginseng spectra were processed using first derivative method. To avoid enhancing the noise resulting from the derivative the spectra were smoothed. This smoothing was done by using the Savitzky-Golay algorithm, a moving window averaging method. Artificial neural network (ANN), support vector machine (SVM) as the new pattern recognition technology, and wavelet transform (WT) were applied. Firstly, the spectrum variables of infrared spectroscopy were compressed through the WT technology before the models were established, in order to reduce the time in establishing models. Then, the identification models of cultivation area of ginsengs were studied comparatively by the use of ANN and SVM methods. The corresponding important parameters of models were also discussed in detail, including the parameters of wavelet compressing and training parameters of ANN and SVM models. The simulation experiment indicated that the ANN model can carry on the distinction among 40 samples of ginsengs from Jilin, and the accuracy rate of identification was 92.5%. The radial basis function (RBF) SVM classifiers and the polynomial SVM classifiers were studied comparatively in this experiment. The best experimental results were obtained using RBF SVM classifier with sigma = 0.6, and the accuracy rate of identification was 97.5%. Finally, compared with ANN approach, SVM algorithm showed its excellent generalization for identification results while the number of samples was smaller. The overall results show that IR spectroscopy combined with SVM and WT technology can be efficiently utilized for rapid and simple identification of the cultivation area of ginsengs, and thus provides the certain technology support and the foundation for further researching ginseng and other IR applications.

Regarding raw drugs of the different habitat and the different cultivation condition, its treatment efficacy is different. This is because they contain different chemical composition and different ingredients content proportion, which causes the difference in their infrared spectra. But these differences are extremely slight, and purely differentiating their characteristics from the infrared spectra is extremely difficult. In the present paper, the samples of epimedium brevicornu from different fields of Jilin province were surveyed by Fourier transform infrared (IR) spectra, and the corresponding pretreatment to the spectra data was carried out. Before establishing model through the artificial neural networks, in order to enhance the training speed of the ANN, the spectra variables were compressed through the wavelet transformation, and the parameters of the ANN model were also discussed in detail. The model can distinguish the producing area of the 42 samples of epimedium brevicornum correctly, avoiding the separation and drawing of raw drugs with traditional spectroscopy analysis at the same time, thus offer an effectively and reliable basis for the quality controls and modernized management of Chinese medicine.