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BACKGROUND: At present, lumbar interbody fusion is widely used in the treatment of a variety of lumbar diseases. However, how to reduce postoperative complications such as pseudarthrosis formation, screw loosening and fracture, and cage failure remains a serious challenge. OBJECTIVE: To analyze the effect of total lumbar range of motion on the stress or strain of bone grafts, cage, and screw-rod system, so as to better guide patients to carry out lumbar activities to reduce the risks of pseudarthrosis formation and instrumentation failure. METHODS: An intact human L1-S1 finite element model was constructed using Mimics, 3-Matic, HyperMesh, and Abaqus software and the transforaminal lumbar interbody fusion was simulated. The average strain of the interbody bone grafts and the peak stresses of the cage and screw-rod system were compared before and after applying the bending moment, and the changing trend with the total range of motion was analyzed. The stress nephogram was drawn to observe the stress distribution. RESULTS AND CONCLUSION: (1) Compared with applying the vertical compression load alone, the average strain of the interbody bone grafts, peak stresses of the cage and screw-rod system after applying bending moment increased by 2.6%-55.3%, 65.6%-166.8%, and 36.0%-353.4%, respectively. (2) With the increase of total range of motion, the average strain of the interbody bone grafts increased nonlinearly and produced the maximum value under left and right axial rotation, while the peak stresses of the cage and screw-rod system increased linearly and produced the maximum value under left and right lateral bending. (3) The stress distribution of the interbody bone grafts and cage was related to the loading condition. The stress of the screw-rod system was mainly concentrated in the interfaces of the screw-bone and screw-rod. (4) Therefore, increasing axial rotation activity after operation may reduce the risk of pseudarthrosis formation, while reducing lateral bending activity may reduce the failure of the cage and screw-rod system [ABSTRACT FROM AUTHOR]

Emergency shelter construction is one of the important measures to enhance the disaster prevention and mitigation capabilities of the entire society and effectively respond to emergencies. In order to explore the spatial distribution characteristics and influencing factors of emergency shelters in Hebei Province, data on the distribution of emergency shelters in Hebei Province were collected. Various methods such as coefficient of variation, imbalance index, spatial Gini coefficient, and global Moran's index were used to explore the spatial distribution characteristics of emergency shelters in Hebei Province. Methods such as geographic detectors were utilized to analyze the influencing factors of spatial distribution. The basic conclusion is that the spatial distribution of emergency shelters in Hebei Province shows a balanced distribution at the urban and geographical regional scales, presenting an overall clustering trend, and exhibiting characteristics of large dispersion and small clustering. The spatial distribution of emergency shelters is influenced by various factors such as topographical, demographic, economic, and urban development factors, among which topographical factors have the greatest impact. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering 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 Mine Automation is the property of Industry & Mine Automation 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 Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering 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.)

BACKGROUND: Polyetheretherketone rod is a new material for semi-rigid fixation; however, its biomechanical properties in posterior lumbar interbody fusion remain unclear. OBJECTIVE: To compare the biomechanical properties of polyetheretherketone rods and titanium rods in posterior lumbar interbody fusion, and try to answer whether polyetheretherketone rods have the potential to be a substitute for titanium rods, especially when the anterior column of the spine is not adequately supported. METHODS: An intact L3-5 lumbar model was constructed using the finite element method. The four posterior lumbar interbody fusion constructs were developed: (1) polyetheretherketone rods with cage; (2) titanium rods with cage; (3) polyetheretherketone rods with bone grafts alone; and (4) titanium rods with bone grafts alone. The range of motion, stress and strain of the related structures were compared among the four posterior lumbar interbody fusion constructs. RESULTS AND CONCLUSION: (1) There was no significant difference in the L4/5 range of motion among all surgical models. (2) Compared to titanium rods, polyetheretherketone rods increased the average strain of interbody bone grafts and the peak stresses of endplates and cages and reduced the peak stresses of the screws and bone-screw interfaces. The ratio of peak stress to yield stress for the polyetheretherketone rods (6%–26%) was higher than that for the titanium rods (3%–12%). (3) Polyetheretherketone rods only slightly reduced the range of motion and disc stress at the L3/4 segment. (4) Compared to titanium rods, polyetheretherketone rods maybe reduce the risks of pseudoarthroses, screw breaking, and loosening but lead to the higher risks of endplate collapse, cage failure, and rod fracture. Polyetheretherketone rods may have a weak advantage over titanium rods in retarding adjacent segment degeneration. Polyetheretherketone rods may be an alternative when interbody fusion is performed with bone grafts alone instead of cages. [ABSTRACT FROM AUTHOR]

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.)

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China 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 the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths 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 Engineering Science Research & Application is the property of Omniscient Pte. 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 Journal of Shaanxi University of Science & Technology is the property of Journal of Shaanxi University of Science & Technology 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 Society: Chinese Journal of Sociology / Shehui is the property of Society: Chinese Journal of Sociology 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 Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation 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 Nonferrous Metals Engineering is the property of Beijing Research Institute of Mining & Metallurgy Technology Group 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.)

Faced with the background of natural resources integration and the more complex land use structure, it is difficult to effectively meet the demand for rational land use planning with a single land use structure optimization method. Considering the objectives of sustainable utilization of land use, ecological civilization, rural development, and urban- rural integration, we constructed an integrated system for land use structure and layout optimization, which will play a positive role in improving the applicability of planning. This study first sets three scenarios of natural evolution, economic priority, and ecological priority, and then uses the MOP model (multi-objective planning model) to calculate the optimal land use structure under different scenarios. Finally, it can carry on land use layout optimization based on the GeoSOSFLUS model in 2030, Jintan district, Jiangsu province, China. Results show that, by integrating the MOP and GeoSOS- FLUS models and adopting the "Structure + Constraint + Layout + Criterion" approach to optimize the land use structure and layout in the county, it is conducive to optimize the quantitative land use structure and improve the land use spatial distribution; from the results of the case analysis, the area of industrial and mining land in cities and towns has increased by 39% and 95% under the natural evolution and economic efficiency priority scenarios; the forest land has increased by 40% under the eco-efficiency priority scenario; rural settlements decreased by 33%, 66% and 66%, respectively in the three scenarios. Under the three development scenarios, the spatial pattern will face the two-level differentiation of urban space and ecological space. In the later period of regional development, it is necessary to strengthen the coordinated development of urban and rural land use and ecological protection, and promote a balanced spatial distribution. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources 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 China Sciencepaper is the property of China Sciencepaper 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 Xi'an Polytechnic University is the property of Editorial Department of Journal of Xi'an Polytechnic University 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.)

To deal with the parameter estimation problem in multi-function radars( MFR) based on stochastic context-free grammar( SCFG) model,this paper developed a new method of MFR parameter estimation problem based on Earley parsing called EIO algorithm on the basis of traditional inside-outside( IO) algorithm and viterbi-score( VS) algorithm. This method pre-processed the intercepted radar data by combining IO algorithm with Earley parsing to handle arbitrary grammar production rules. It utilized the EIO algorithm to realize the learning of grammatical production rules probabilities and MFR parameter estimation. Theoretical analysis and simulation results show that the modified algorithm can reduce the computation complexity,memory complexity and running time while keeping the same level of estimation accuracy,validates the correctness and effectiveness of this method. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of 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 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.)