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Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To compare the efficacy of four methods on removal of calcium hydroxide in root canals. Methods Forty simulated resin root canals with 45° curvature were randomly divided into four groups. After root canal preparation, the apical foramen were sealed with glass-ionomer cement, the root canals were filled with calcium hydroxide, and the root canal orifices were sealed with hard wax. After being placed in a constant temperature water bath at 37 ℃ for 14 days, four methods including needle irrigation, Er: YAG laser irrigation, EDDY working tip irrigation and ultrasonic irrigation were used to remove the calcium hydroxide. The resin root canals before and after calcium hydroxide removal were scanned by cone-beam CT, and the scanning results were imported into Mimics software. Three-dimensional reconstruction of each root canal was performed by Mimics software, and the volume of calcium hydroxide in each root canal was calculated. The volume of calcium hydroxide was V1 before removal and V2 after removal, and the clearance rate was (V1 -V2)/V1 * 100%. Rank sum test was used for statistical analysis. Results There was no significant difference in the initial volume of calcium hydroxide paste among the groups before removal (P > 0.05). After removal, the residual volume of calcium hydroxide paste in Er: YAG laser group was 0.129 6 (0.092 0, 0.174 3) mm³, which was less than the other three groups, and the difference was statistically significant (P < 0.05). The reduction rate of calcium hydroxide paste was 99.63 % (99.53%, 99.70%) in Er: YAG laser group, which was higher than the other three groups, and the difference was statistically significant (P < 0.05). The reduction rates of EDDY group and ultrasonic group were 99.08% (98.85%, 99.19%) and 99.04% (98.51%, 99.15%), respectively. There was no significant difference between the two groups (P > 0.05), but they were higher than needle group 74.99% (64.43%, 88.07%) (P < 0.05), and the difference was statistically significant. Conclusions In this study, Er: YAG laser-activated irrigation, EDDY irrigation and ultrasonic irrigation have better removal effects on calcium hydroxide paste in root canals than traditional needle irrigation. Compared with other four methods, Er: YAG laser-activated irrigation has the highest removal efficiency, EDDY irrigation and ultrasonic irrigation have similar removal efficiency, but none of the four methods could completely remove calcium hydroxide paste from the curved root canals. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Practical Pharmacy & Clinical Remedies is the property of Editorial Department of Practical Pharmacy & Clinical Remedies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Social Sciences & Philosophy is the property of Research Center for Humanities & Social Sciences, Academia Sinica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water delivery canals play an important role in highly efficient water use in arid and semi-arid regions in China. Those regions mostly belong to cold region widely distributed with seasonal frozen soils. Thus, canal lining is susceptible to frost damage because of the heave of freezing soil and the adfreezing constraint between foundation and lining. Double geo-membranes between lining and foundation soil have an advantage in relieving adfreezing strength and adjusting lining displacement to adapt nonuniform frost heave but reduce the stiffness and stability of lining structure. To find the best layout of double geo-membranes and quantitative analysis on the adaptation of the double geo-membranes, a heat-moisture-stress coupling model of frost heave for arc bottom trapezoidal canal was established by finite element method. A bilinear interaction model between layers of cushion was considered by thin elastic layer element, of which the friction force was expressed as reaction force relating to its shear stiffness. A total of 3 different layout forms of composite cushion (membrane-membrane, membrane-fabric and fabric-fabric) were simulated by various shear stiffness parameters. The lining stress and deformation were compared by different canal sections and layout forms of double membranes cushion under lining. The result showed that: 1) For narrow and deep lined canals, the smaller the friction between membranes would result in the more uniform frost heave but the worse overall structure stability. While for wide and shallow canals, it was disadvantageous for neither frost heave uniformity nor overall stability when reducing the friction between membranes. Hence considering the requirements of frost heave uniformity and stability, the membrane-fabric form was suitable for both narrow and deep lined canals and wide and shallow lined canals. 2) The arch structure at the bottom of canal had an arch effect that could increase the axial compressive force along lining when bearing the heave force at the lower surface of lining. But as decreasing friction by double membranes, the arch effect was weaken, causing the extra tensile stress in the slope of canal lining. Therefore, considering the requirements of structure strength, the membrane-fabric and fabric-fabric form was suitable for anti-frost damage of canal lining. Double membranes cushion with less adfreezing strength such as membrane-membrane and membrane-fabric combinations could relieve the freezing constraint and adjust lining uneven frost heave deformation, but may lead to large displacement and damage tensile stress as a result of the release of arch effect at the bottom of the canal. Therefore, double membranes cushion with some small friction could not ensure the safety of strength and stiffness of lining structure. In addition, proper adfreezing strength was helpful in adjusting uneven frost heave by partly slip and limiting overall deformation. Furthermore, the arch effect should be rationally utilized to produce compressive stress along lining. In consequence, when membrane-fabric was used as interface between membranes, the displacement variance of lining decreased by 25% and the frost heave stress reduced by more the 50%, while the overall displacement increased by 0.2 cm or less. This double membranes form, which was suitable for narrow and deep canals as well as wide and shallow canals, could meet the requirements of strength, stiffness and stability for lining structure, and could improve the adaptive ability for frost heave damage. The results could provide information for selecting reasonable layout of double membranes cushion lining canals in cold region. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)