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Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology 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 Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power 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.)

BACKGROUND: The cannulated lag screw technique has many advantages in the treatment of spondylolysis, but there is still the risk of fracture and loosening of the internal fixation. OBJECTIVE: To analyze the biomechanical stability of cannulated lag screw treatment of spondylolysis by establishing L4-S normal model, spondylolysis model and cannulated lag screw treatment model of spondylolysis through three-dimensional finite element software. METHODS: One male healthy young soldier volunteer was selected. 3D CT scan was performed on the volunteer’s lumbar spine and sacral spine. The imaging data were obtained and saved in Dicom format. CT data were imported into Mimics research 21.0 software to initially establish a geometric model, and deviation analysis was carried out. The obtained model was output in STEP format. Three groups of models of normal L4-S segment, L5 bilateral isthmus and cannulated lag screw in the treatment of spondylolysis were established after imported into Solidworks 21.0 software. They were represented by A, B and C respectively. The biomechanical characteristics of the three groups of models were compared under five motion states, such as axial compression, flexion, extension, left bending, and left rotation. RESULTS AND CONCLUSION: (1) Compared with models A and C, model B had the largest overall maximum displacement under the five working conditions of axial compression, flexion, extension, left bending, and left rotation. However, the overall maximum displacement of models A and C was not significantly different. (2) After removing the internal fixation in the model C, the maximum stress trend was similar to the model A. The stress of the model B was significantly higher than that of the models A and C during left bending and left rotation. (3) The overall maximum rotation angle of the three groups of models showed that the maximum rotation angle of the model B under the five working conditions was significantly larger than that of the models A and C. The models A and C were similar. The range of motion of the L4 vertebral body in the three groups did not change significantly. The range of motion of the L5 vertebral body in the model B was significantly higher than that in the models A and C, and it was more obvious in the left rotation and left bending. (4) These findings indicate that under the condition of physiological movement of the spine, the change trend of cannulated lag screw in the treatment of lumbar spondylolysis model is the same as that of normal model, which obtains good biomechanical stability and retains the normal mechanical characteristics of the spine, but excessive extension and rotation should be avoided immediately after operation. BACKGROUND: The cannulated lag screw technique has many advantages in the treatment of spondylolysis, but there is still the risk of fracture and loosening of the internal fixation. OBJECTIVE: To analyze the biomechanical stability of cannulated lag screw treatment of spondylolysis by establishing L4-S normal model, spondylolysis model and cannulated lag screw treatment model of spondylolysis through three-dimensional finite element software. METHODS: One male healthy young soldier volunteer was selected. 3D CT scan was performed on the volunteer’s lumbar spine and sacral spine. The imaging data were obtained and saved in Dicom format. CT data were imported into Mimics research 21.0 software to initially establish a geometric model, and deviation analysis was carried out. The obtained model was output in STEP format. Three groups of models of normal L4-S segment, L5 bilateral isthmus and cannulated lag screw in the treatment of spondylolysis were established after imported into Solidworks 21.0 software. They were represented by A, B and C respectively. The biomechanical characteristics of the three groups of models were compared under five motion states, such as axial compression, flexion, extension, left bending, and left rotation. RESULTS AND CONCLUSION: (1) Compared with models A and C, model B had the largest overall maximum displacement under the five working conditions of axial compression, flexion, extension, left bending, and left rotation. However, the overall maximum displacement of models A and C was not significantly different. (2) After removing the internal fixation in the model C, the maximum stress trend was similar to the model A. The stress of the model B was significantly higher than that of the models A and C during left bending and left rotation. (3) The overall maximum rotation angle of the three groups of models showed that the maximum rotation angle of the model B under the five working conditions was significantly larger than that of the models A and C. The models A and C were similar. The range of motion of the L4 vertebral body in the three groups did not change significantly. The range of motion of the L5 vertebral body in the model B was significantly higher than that in the models A and C, and it was more obvious in the left rotation and left bending. (4) These findings indicate that under the condition of physiological movement of the spine, the change trend of cannulated lag screw in the treatment of lumbar spondylolysis model is the same as that of normal model, which obtains good biomechanical stability and retains the normal mechanical characteristics of the spine, but excessive extension and rotation should be avoided immediately after operation. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology is the property of Automobile Technology 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 Automobile Technology is the property of Automobile Technology 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 Automobile Technology is the property of Automobile Technology 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 Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. 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 Shipin Kexue/ Food Science is the property of Food Science 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.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science 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.)

Copyright of Application Research of Computers / Jisuanji Yingyong Yanjiu is the property of Application Research of Computers Edition 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 explore the effect of EphB/EphrinB signaling pathway on the osteogenic differentiation of mouse bone marrow derived mesenchymal stem cells (BMSCs) and the postmenopausal osteoporosis animal model in mice. Methods 1) Twenty-four healthy 8-week-old BALB/c mice were randomly divided into castration group (OVX group) and sham operation group (Sham group). The expression level of Eph/Ephrin signaling pathway in BMSCs was detected. 2) The ovariectomized mice were divided into 4 groups. The Eph receptor agonists EfnB1-Fc and EfnB2-Fc, Eph receptor inhibitor EphB2-Fc, and human IgG-Fc as control, were intraperitoneally injected, respectively. The mice were sacrificed by cervical dislocation 10 weeks after the surgery. The femoral bones were compared under micro-CT analysis. The bone marrow of the femurs and the tibia was extracted from the ovariectomized and sham-operated mice. BMSCs were isolated and cultured by density gradient centrifugation and identified to P3. After osteogenic induction for 7 days, the expression levels of Runx2, ALP, Osterix, OPG, and RANKL were detected using real-time PCR. After 14 days and 21 days of osteogenic differentiation, the ability of osteogenic differentiation was observed with ALP staining and Alizarin red staining. Results Compared with those in the OVX group, the expressions of EfnA2, EphB4, EfnB2, EfnB1, and EphA4 in the Sham group increased significantly (P<0.01), and the expression difference was similar to those in humans. The expressions of EfnA2 and EfnB2 reduced significantly in the Sham group (P<0.01). After 10 weeks, the results of micro-CT showed that compared with the control group, the trabecular structure in the Sham group, and EfnB1-Fc, EfnB2-Fc, and EphB2-Fc in the castration group was relatively intact and the trabecular bone density was better (P<0.01). Compared with those in EfnB1-Fc and EfnB2-Fc castration groups, the bone mineral density and bone volume fraction in the Sham group and EphB2-Fc castration group increased significantly (P<0.01). The results of real-time PCR for detection of osteogenesis-related genes indicated that the expressions of ALP and Osterix in EfnB1-Fc, EfnB2-Fc, and EphB2-Fc castration groups were significantly higher than those in human IgG-Fc castration group. EfnB1-Fc and EphB2-Fc increased ALP activity and mineralization by BMSCs, and it is more obvious in EphB2-Fc group. Compared with that in the control group, the expression of RANKL in EfnB1-Fc, EfnB2-Fc, and EphB2-Fc castration groups was not significantly different (P>0.05), but the expression of OPG increased significantly (P<0.01). Among those, the increase of OPG/RANKL ratio in EfnB1-Fc and EphB2-Fc group was the most significant (P<0.01). Conclusion EphB2/EfnB1 signaling pathway can reverse the bone loss caused by castration, up-regulate ALP and Osterix expression, promote osteogenic differentiation of BMSCs, and affect the function of BMSCs in ovariectomized mice by regulating OPG/RNAKL ratio, indirectly affecting the differentiation of osteoclasts. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science 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.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science 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.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science 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.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research 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 Chinese Journal of Osteoporosis is the property of Chinese Journal of Osteoporosis 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 Chinese Journal of Osteoporosis is the property of Chinese Journal of Osteoporosis 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.)