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A simplified three-dimensional brake model with crater structure is established by using the finite element software Abaqus, and the influence of the depth, diameters, degrees and types of craters on the temperature and stress of the brake disc is investigated by combining the thermal coupling theory and the orthogonal test method. On this basis, the temperature and stress fields of brake discs with different non-smooth surface forms are analyzed, and the influence of temperature with radius on non-smooth discs with different braking initial speeds and pressures during emergency braking is investigated under the optimal combination. The results show that the square pit brake disc with the pit depth of 5 mm, the diameter of 8 mm and the 20° interval between adjacent pits in the circumferential direction has the smallest temperature and stress by the orthogonal test method, which is the optimal combination. Among them, the square pit brake disc has the best heat dissipation performance. With the increase of the initial speed and pressure of braking, the temperature of this brake disc surface gradually increases, the highest temperatures of the brake disc all appeares in the brake disc radius of 136 mm.

Using the theory related to thermal coupling and heat transfer, the finite element software Abaqus is used to establish an orthogonal anisotropic C/SiC model of an automotive ventilated brake disc. Based on this model, different braking initial velocities, different braking pressures and different longitudinal expansion coefficients of the brake disc during emergency braking are simulated and analyzed. The results show that the temperature profile of the nodal unit of the brake disc exhibited "sawtooth" fluctuations under the effect of thermal coupling, and the thermal stresses mainly appeared in the middle region of the friction contact. The higher the braking pressure and initial speed during emergency braking are, the higher the temperature rise of the disc surface will be. However, the effect of different disc expansion coefficients on the maximum disc temperature is not significant.

In order to explore the effect of different dietary structures (normal diet, high-protein diet, high-fat diet, high-sugar diet) on the bioavailability and antioxidant activity of citrus carotenoids, the changes in the carotenoid content, ferric reducing capacity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity of mandarin pulp were monitored during in vitro simulated digestion. The correlation between carotenoid content and antioxidant activity was also evaluated. The results showed that as digestion progressed, the contents of total carotenoids and two carotenoid monomers in mandarin pulp mixed with whey protein, soybean oil and corn starch in four different proportions decreased continuously and the antioxidant activity of carotenoids in the four groups also decreased significantly (P < 0.05). Among these groups, the content of carotenoids in the high-fat diet group was higher at all digestion stages, and the antioxidant activity of carotenoids in this group was also stronger. There was a significantly positive correlation between the antioxidant activity and content of citrus carotenoids (P < 0.05). The comprehensive analysis showed that dietary structures had a great impact on the bioavailability and antioxidant activity of citrus carotenoids. The bioavailability of carotenoids in the high-fat diet group was (24.08 ± 1.78)% and significantly higher than that ((19.26 ± 1.06)%) in the normal diet group (P < 0.05), and the antioxidant activity of carotenoids in the high-fat diet group was the strongest. The bioavailability of carotenoids in the high-protein diet group was (15.27 ± 0.90)% and significantly lower than that in the normal diet group (P < 0.05), while there was no significant difference in carotenoid bioavailability between the high-sugar ((19.71 ± 1.58)%) and normal diet groups. This study suggests that high-fat diet can significantly improve the bioavailability and antioxidant activity of citrus carotenoids.

ObjectiveTo investigate the P300 evoked by Stroop Color Word Task in children with emotional neglect, and to explore their implication for inhibition control.MethodsA cluster sampling was conducted for the first grade students of a middle school in Sanmenxia City, Henan Province. The students from 3 classes were assessed by standard Raven reasoning test and Child Neglect Scale (CNS), and a total of 147 eligible students were screened out. Children were divided into the emotional neglect group (n=40) and the control group (n=40) according to the 27% before and after the score of CNS emotional neglect factor. Both groups completed the Stroop Color word task, and EEG data were collected to compare the response time, accuracy, amplitude and latency of P300 between the two groups.ResultsThe CNS total score and the scores of safety neglect, communication neglect, physical neglect and emotional neglect factors in the emotional neglect group were significantly higher than those in control group (t=15.003, 4.301, 11.495, 4.803, 23.957, P

Action recognition is an important area in computer vision. An action recognition system based on SoC FPGA and CNN model is presented. A pipelined LK optical flow module and a pedestrian detection module based on HOG and SVM are realized. The results of detection of dynamic pedestrian and static pedestrian are merged to recognize the area where the person is. The image and optical flow in the area are both input into the CNN model, to recognize what action it is. An ISA-NPU is proposed to realize the computation of the CNN model. The system is realized in Altera DE10-Nano Kit. With the co-operation of hardware and software, the system can recognize actions such as stand, walk, wave and squat. The system is accurate in recognition and flexible for expansion and modification of the CNN model.

Polar code is an error correction coding technique, which can prove from the mathematical point of view to reach Shannon′s limit. However, the traditional decoding algorithm, such as the successive cancellation(SC) and the successive cancellation list (SCL) decoding algorithms, have high complexity and latency in the decoding ends. This paper studies the principle and structure of the decoding algorithm, which proves that the decoding operation of some nodes is redundant. Therefore, simplified SC decoding and SCL decoding algorithm is proposed. It is proved that the simplified decoding algorithm can reduce the complexity of the decoding algorithm and maintain the original error rate performance at the same time.

Cracked tooth is a common type of tooth fracture with diverse symptoms, different treatment principles and unpredictable prognosis. The available remedies for immediate, intermediate and definitive managements include occlusal adjustment, orthodontic band, bonded composite resin, onlay, full crown and so on. For teeth with localized crack and vital pulp, bonded composite resin and onlay with cuspal coverage are also protective remedies besides tradi⁃ tional full ⁃crown restoration. Once pulpal infection occurs, root canal therapy and full ⁃crown restoration is indicated. Clinical determination should be made with comprehensive consideration of the location and depth of the crack, risk of extension and pulpal condition. This review will focus on the traits and prognosis of various therapy options, so as to pro⁃ vide evidence⁃based treatment planning of cracked tooth.

Aim To investigate the effects of astragalus polysaccharide and hirudin combined intervention on lipid accumulation, mitochondrial membrane potential and apoptosis-related proteins in macrophages induced by oxidized low density lipoprotein (ox-LDL). Methods RAW264. 7 cells were incubated with 100 mg/ L ox-LDL for 24 h to establish a foam-cell model, which were treated by astragalus polysaccharide and hirudin after dose optimization. The control group, model group, astragalus polysaccharide group, hirudin group and the combined intervention of the two drugs group were established. Oil red O staining and oxidase method were used to detect the cholesterol contents in macrophages induced by ox-LDL, flow cytometry was used to detect the early apoptosis rate, late apoptosis rate and total apoptosis rate of macrophages, the changes of mitochondrial membrane potential were detected by laser confocal microscopy, Western blot was used to detect the expression levels of anti-apoptotic protein Bcl-2, proapoptotic protein Caspase-3 and Bax. Results The contents of cholesterol in macrophages of the astragalus polysaccharide and hirudin combined intervention group were decreased than those in the hirudin group or astragalus polysaccharide group significantly (P<0.05). Compared with the model group, the astragalus polysaccharide and hirudin combined intervention could reduce the early apoptosis rate and total apoptosis rate of macrophages induced by ox-LDL (P<0.01), increase the mitochondrial membrane potential of macrophages (P<0.01), reduce the expressions of Caspase-3 and Bax, and increase the expression of Bcl-2 protein (P< 0.05) significantly. Conclusions The astragalus polysaccharide and hirudin combined intervention in reducing lipid accumulation in macrophages is superior to drug treatment alone. The combined treatment of the two drugs can reduce the apoptosis rate of macrophages induced by ox-LDL. Its mechanism may be related to regulate mitochondrial membrane potential and regulate the expressions of proapoptotic protein Caspase-3, Bax and anti-apoptotic protein Bcl-2. [ABSTRACT FROM AUTHOR]

Objective To investigate and understand the semen quality sitration of normal fertility men in the partial areas of Guangxi Zhuang Autonomous Region during 2011 by the multicenter cooperation. Methods To study semen quality of 965 fertility men from four reproduction medcine centers in Guang xi zhuang autonomous Region. Their basic examine include age, longth of penis, volume of testis and so on. Semen samples were compared with the World Health Organization criteria. Questionnaire were used by special trainer for all reproductive centers. The semen quality were compared among different ages groups, nation groups, rigion groups and culture groups. Results Sperm progressive motility and sperm morphology reached 61.7% , 73.5% of normal levels respectively. Others reached above 80.0%. Sperm motility and sperm progressive motility were (64.493± 17.199)%, (47.478±15.305)% in 18-<30 group respectively. Sperm density of Han group and sperm morphology of Zhuang group were best among all groups. Culture degree did not affect semen quality. Conclusions The sperm motility bias and sperm deformity degree in the partial areas of Guangxi Zhuang Autonomous Rigion are higher and have local difference, which needs to further perfect the inrestigation data and felermine the influencing factors. [ABSTRACT FROM AUTHOR]