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BACKGROUND: The tissue mechanical properties of trabecular meshwork are closely related to the resistance of the aqueous humor outflow. Considering the porous structure of trabecular meshwork, the apparent elastic modulus of trabecular meshwork tissue can be obtained by atomic force microscope indentation technique. However, the information of tissue elastic modulus cannot be obtained by this method. Therefore, there is a lack of quantitative research on the relationship between apparent and tissue elastic modulus of the trabecular meshwork. OBJECTIVE: To further analyze the relationship between apparent and tissue elastic modulus of the trabecular meshwork by finite element simulation. METHODS: Based on the two-photon confocal images of rat trabecular meshwork, a three-dimensional structure model of the trabecular meshwork was constructed. The finite element analysis was used to simulate the indentation experiment to obtain the apparent elastic modulus of the trabecular meshwork at different positions, and the tissue elastic modulus was obtained by simulating the whole indentation experiment. RESULTS AND CONCLUSION: The parameters of the first-order Ogden model based on the atomic force microscope indentation experiment were obtained. The average value of the apparent elastic modulus of the trabecular meshwork obtained by simulating the atomic force microscope indentation experiment was within the range of the tissue elastic modulus of the trabecular meshwork tissue when the compression ratio was 1%-2%. This study quantifies the relationship between apparent and tissue elastic modulus of trabecular meshwork tissue and provides a methodological reference for the study of mechanical properties of trabecular meshwork tissue. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Fresh Gentiana rigescens was collected from Yunxian Lincang. Taking the roots and stems of Gentiana rigescens as the research objects, the contents of gentiopicroside, loganic acid, swertimarin and sweroside, as well as total ash, acid-insoluble ash and extract in dried Gentiana rigescens samples were determined by using 9 different primary processing methods. According to the standard of Pharmacopoeia of the People’s Republic of China, the quality of medicinal materials was comprehensively evaluated. The result showed that the contents of active ingredient in Gentiana rigescens with different processing methods were different, among which the content of gentiopicroside and loganic acid in the sample treated with water washing and drying (SXHG) was significantly higher than any other treatments. At the same time, the drying time required was the shortest, only 12 hours, far lower than any other treatments. The total ash, acid insoluble ash and extracts of the sample treated by water washing and drying (SXHG) met the standards of the Pharmacopoeia of the People’ s Republic of China. According to the principal component analysis, the comprehensive quality of water washing and drying (SXHG) of Gentiana rigescens sample was the best, followed by washing free dried in the shade (MXYG). However, the total ash and extracts of the samples processed by this method did not meet the standards of the Pharmacopoeia of the People’s Republic of China. Water washed and dried in the shade (SXYG) was widely used by farmers in traditional production, and could be used as an auxiliary drying method in the production area processing according to the weather, site and other actual conditions. Overall consideration, the processing method of Gentiana rigescens in the producing area should be water washing and drying (SXHG). If the processing amount of medicinal materials was large, the method of water washed and dried in the shade (SXYG) could be used according to the weather, site and other actual conditions. [ABSTRACT FROM AUTHOR]

Objective: To examine the validity and reliability of the Chinese version of the Simulator Sickness Questionnaire（SSQ） in college students. Methods: Totally 188 college students were selected to experience virtual reality environments and assessed with the SSQ. One sample（n=94） was subjected to exploratory factor analysis, while the other sample（n=94） was subjected to confirmatory factor analysis. After 2 weeks, 50 of them were selected to participate in the retest. Results: Exploratory factor analysis showed that the SSQ consisted 3 factors, namely nausea, oculomotor and disorientation, accounting for 45. 3% of the total variance. The confirmatory factor analysis confirmed the 3-factor model fit well（χ2/df=1. 14, RMSEA=0. 039, IFI=0. 96, CFI=0. 96, GFI=0. 90）. The Cronbach α coefficient of the total questionnaire was 0. 75, and the Cronbach a coefficients of the 3 factors were 0. 60, 0. 63 and 0. 64, respectively. The test-retest reliabilities were 0. 76 for the total questionnaire and0. 51, 0. 70, 0. 78 for the 3 factors, respectively. Conclusion: It suggests that the Chinese version of the Simulator Sickness Questionnaire（SSQ）has acceptable structure validity and reliability in college students. [ABSTRACT FROM AUTHOR]

Objective To conduct dual phases radiologic-anatomic research of pulmonary vein and left atrium in normal adults using dual source CT cardiac images in order to provide reference information for the evaluation of clinical patients. Methods A total of 218 individuals who had underwent dual-source cardiac CT with best systolic and diastolic phase images were enrolled in the study.The three-dimensional reformation technique was used at the workstation to evaluate the anatomical variation of pulmonary veins， the morphology of pulmonary vein apertures and left atrium. All the data were recorded and analyzed statistically. Results In the pulmonary vein variations，the accessory pulmonary veins were more likely to occur on the right side（0.92% on the left side and 8.26% on the right side），and the common pulmonary veins were more likely to occur on the left side（13.3% on the left side and 0.92% on the right side）.The left common type was the most frequently occurred variation followed by the right middle type and other mixed types were rare. In the pulmonary vein measurement，anterior-posterior diameter was smaller than superior-inferior diameter. The superior pulmonary vein apertures were larger than the inferior pulmonary vein apertures，and the right pulmonary vein apertures were larger and more round than the left pulmonary vein apertures. The order of the size of pulmonary vein apertures is the right superior pulmonary vein （RSPV），the right inferior pulmonary vein（RIPV），the left superior pulmonary vein（LSPV）and the left inferior pulmonary vein（LIPV）aperture from the largest to the smallest in turn. RSPV aperture was the largest and most round one while LIPV aperture was the smallest and most oval one. The accessory pulmonary vein aperture was smaller than that of the routine type，and the common pulmonary vein aperture was larger and more oval than that of the routine type. Left atrial anterior-posterior diameter was the smallest one，then the longitudinal and transversal diameter in turn.The comparison of the dual phases data showed that the pulmonary vein aperture in the systolic phase was larger and more round than that in the diastolic phase，and the left atrial diameter in the systolic phase was also larger than that in the diastolic phase. Conclusion Pulmonary vein variation was common.The size and morphology of pulmonary veins and left atrium were related to cardiac cycle，and dual source cardiac CT could display and evaluate the pulmonary vein and left atrium effectively. [ABSTRACT FROM AUTHOR]

【Objective】 The accumulation characteristics of effective components in Gentiana rigescens were studied under different intercropping patterns. 【Method】 HPLC method was used to determine the contents of gentiopicroside, sweroside, swertiamarin and loganic acid in Gentiana rigescens. 【Result】The results showed that the average contents of gentiopicroside, sweroside, swertiamarin and loganic acid were 67.95, 1.85, 9.69 and 7.19 mg/g, respectively. The content of gentiopicroside, which was(85.99±9.58)mg/g, was the highest in Gentiana rigescens-Alnus nepalensis compound planting. The content of sweroside, which was(2.05±0.23)mg/g, was the highest in Gentiana rigescens-Cunninghamia lanceolata. The content of swertiamarin, which was(10.10±0.95)mg/g, was the highest in Gentiana rigescens-Juglansregia Linn. The content of loganic acid, which was(9.74±1.94)mg/g, was the highest in Gentiana rigescens-Juglansregia Linn. The results of correlation analysis showed that the content of gentiopicroside were significantly and positively correlated with that of swertiamarin(R=0.35, P<0.01), while the content of sweroside was positively correlated with that of loganic acid(R=0.49, P<0.01) and swertiamarin(R=0.41, P<0.01), respectively. 【Conclusion】 The contents of effective components in Gentiana rigescens under different intercropping patterns are different, which may be related to the microenvironment where they grew. [ABSTRACT FROM AUTHOR]