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Background and purpose: Radiotherapy is an important means to treat pelvic tumors. It is important to improve the accuracy of radiotherapy and enhance the effectiveness. This study aimed to compare and analyze the influence of positioning errors during the radiotherapy of patients using surface guided radiotherapy (SGRT) automatic positioning versus traditional surface marking positioning. Methods: We performed a retrospective analysis of 50 patients with pelvic tumors who received radiotherapy and had simple positioning fixation methods at the Fudan University Shanghai Cancer Center from April 2023 to April 2024. A total of 25 patients were treated using SGRT (observation group), and 25 patients were treated using traditional surface marking (control group). After positioning according to the two positioning techniques, cone beam computed tomography (CBCT) images were collected. These data were compared with the initial reference computed tomography (CT) images within 6 dimensions. The correction error values of the six dimensions were recorded. We calculated the averages, standard deviations, and the number of cases and probabilities in different interval distributions. SPSS 27.0 was used to perform statistical analysis of the data from the two groups of patients. We also analyzed the correlation of patients in the observation group within the 6 dimensions. Results: The non-parametric test showed significant differences in only the LNG and PITCH directions (P＜0.05). The number of cases (probability) in the observation group with errors less than 3 mm and less than 1 were 108 (86.4%), 93 (74.4%), 108 (86.4%), and 96 (76.8%), 111 (88.8%), 107 (85.6%), respectively. In the control group, the numbers were 113 (90.4%), 107 (85.6%), 118 (94.4%), and 71 (56.8%), 95 (76.0%), 110 (88.0%), respectively. The Spearman correlation analysis showed that in the observation group, the leftright direction had a negative correlation with pitch, roll and yaw, while all other directions were positively correlated. Statistically significant positive correlations (P＜0.05) were found between the superior-inferior and pitch directions, left-right and roll directions, as well as pitch and roll directions, with positive correlation coefficients (r = 0.270, r = 0.301, and r = 0.247). Conclusion: The application of SGRT automatic positioning can achieve the effect of regular surface marking line positioning, has advantages in rotation direction adjustment, and can replace surface marking line positioning where conditions permit. [ABSTRACT FROM AUTHOR]

Objective In order to solve the problems such as too stable traditional foam and difficulty in defoaming.Method Using N-dodecyl-1,3-propanediamine and temperature and salt tolerant anionic surfactant to prepare a CO2 responsive temperature and salt tolerance composite foam system, and uses molecular simulation to explore the stability and response mechanism of the composite foam. Results Results show that N-dodecyl-1,3-propanediamine has good protonation and salt tolerance properties. However, its temperature tolerance is poor, and it does not have response performance. After compounding with sodium dodecyl sulfate (SDS) and sodium dodecyl sulfate, the foaming speed at high temperature is increased by 40%, the foam duration is 3.17 times longer than that before compounding, the temperature resistance is significantly improved, and the foam is defoamed rapidly within a short period after passing CO2. Molecular simulation studies reveal that the S atomic groups contained in SDS will combine with the positively charged N atomic groups in C12N(CH3)N(CH3)2 and lose surface activity, resulting in poor stability of the foam, which is also responsible for the responsive defoaming. Conclusion The composite system has good temperature and salt resistance and responsiveness, and can realize responsive defoaming after foam drainage and gas production in harsh environments which has broad application prospects. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica 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 Qing History Journal is the property of Renmin University of China, Institute of Qing History 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 Current Biotechnology (2095-2341) is the property of Chinese Academy of Agricultural Sciences, Institute of Biotechnology 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.)

The large-scale cavitation water tunnel testing facility is currently the largest water tunnel system in China. To evaluate the structural strength and seismic design safety of the large cavitation water tunnel test facility, a three-dimensional numerical analysis of the water tunnel structure was carried out. The finite element model of the complete structure of the cavitation water tunnel was established, and the structural strength under the normal working condition and the extreme working condition considering the seismic load was calculated and analyzed. The seismic inertial acceleration load was calculated based on the mode-superposition response spectrum method, and the seismic displacement response of the structure was checked. The results show that the structural deformation of the cavitation water tunnel is mainly reflected in the expansion deformation of the inner wall of the water tunnel under the normal working condition, and mainly reflected in the horizontal displacement of the top of the water tunnel caused by the seismic load under the extreme working condition. The high stress regions of the water tunnel are mainly located on the inner wall and the stiffener at the corner of the structure, which can pay the way for building the large cavitation water tunnel of our country in the future. [ABSTRACT FROM AUTHOR]

Massive red spiral galaxies (MRSGs) are supposed to be the possible progenitors of lenticular galaxies (S0s). We select a large sample of MRSGs (⁠|$M_*\gt 10^{10.5}\rm {\rm M}_{\odot }$|⁠) from Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) DR17 using the g − r colour versus stellar mass diagram, along with control samples of blue spirals and S0s. Our main results are as follows: (1) After comparing the Sérsic index, concentration parameter, asymmetry parameter distribution, size–mass relation, and Σ1 (stellar mass surface density within the central 1 kpc)−mass relation, we find MRSGs are similar to S0s and have more compact and symmetric structures than blue spirals. MRSGs also resemble S0s in Dn4000, metallicity, Mgb/ |$\rm \left\langle Fe \right\rangle$|⁠ , and V /σ radial profile. (2) By using MaNGA 2D spectra data, we separate the spatial regions into inner (R  < 0.8 R e) and outer (0.8 <  R   < 1.5 R e) regions, and detect residual star formation in the outer regions of MRSGs. (3) When we select a sub-sample of MRSGs with NUV −  r   >  5, we find that they are completely star formation quenched in both inner and outer regions. Compared to optically selected MRSGs, NUV −  r selected MRSGs appear to be more concentrated and have more massive dark matter haloes. The similarities between S0s and MRSGs suggest the possible evolutionary trend between MRSGs and S0s. [ABSTRACT FROM AUTHOR]

[Objective] Studying the windbreak and sand fixation effects of highway protection systems can provide scientific basis for the prevention and control of sand damage on regional highways. [Methods] The protection system of the Deng-E Desert Highway in the northeast of Ulanbuhe Desert was taken as the research object, and synchronous observation was conducted on the sediment discharge and wind speed of the protective system. [Results](1) After the sand flow passes through the protection system, the wind speed and total sand transport at each height decrease, and the surface roughness increases. The wind speed in the upwind direction(point B) and downwind direction(point C) of the protection system decreases by 48.7%, 14.4%, and 3.9%, respectively, compared to point A from high to low. The total sand transport rate decreased by 86.4% and 98.3%, respectively, compared to point A, and the surface roughness increases from about 0 cm to 4.92 cm.(2) The vertical distribution of sand particle size shows a significant decrease in medium sand content and a significant increase in fine sand content. The particle size distribution of surface sediment decreases, the frequency distribution curve narrows in some bands, and the sorting ability deteriorates. The particle distribution is uniform and develops towards fine-grained direction, with a range of easily weathered particles ranging from 180 to 200 μm. [Conclusion] For road sand prevention projects, there should be a construction concept of “putting resistance first and combining resistance and fixation”. At the same time, the practice of road wind and sand prevention and fixation systems in this research area can provide important reference experience for road sand prevention in the other regions. [ABSTRACT FROM AUTHOR]

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications 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 Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation 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 Chinese Potato Journal is the property of Northeast Agricultural 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 Journal of Central China Normal University is the property of Huazhong Normal 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 Geology & Resources is the property of Geology & Resources 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 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 Water Conservancy & Electric Power Technology & 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 International Architecture 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 Chinese Journal of Aesthetic & Plastic Surgery is the property of Chinese Journal of Aesthetic & Plastic Surgery 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 Xi'an Jiaotong University (Medical Sciences) is the property of Xian Jiaotong 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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.)

With the rapid development of communication technology and electronic equipment, electromagnetic pollution has affected the normal operation of electronic equipment and the safety of human life. Therefore, the development of electromagnetic shielding materials is of great scientific significance. In recent years, polymer based carbon nanocomposites have developed rapidly in the field of electromagnetic shielding, showing many excellent properties, which have attracted wide attention in academic cireles. Based on our group's understanding and research in the field of electromagnetic shielding, this paper briefly introduces the principle of electromagnetic shielding and the preparation methods of polymer-based carbon nano composites, with emphasis on the research progress of polymer-based carbon nanocomposites prepared by backfilling method. finally, the future development trend and application of electromagnetic shielding materials are prospected. [ABSTRACT FROM AUTHOR]

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical 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 Nanchang University (Natural Science) is the property of Journal of Nanchang University (Natural Science) 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 Nursing of Integrated Traditional Chinese & Western Medicine is the property of Journal of Clinical Nursing in Practice (Editorial Board, Shanghai Jiao Tong University Press) 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.)

Because of the characteristics of hardened steel mold with high hardness and surface characteristics of the complex,the hardened steel mold in the milling process is easy to produce flutter. The flutter will affect the workpiece surface quality and restrict milling efficiency,therefore,the dynamic analysis and stability prediction of hardened steel mould in the milling process have become more and more important. The hardened steel mould milling stability is mainly related to dynamic characteristics of the processing system and dynamic milling process,therefore,the article summarized the research on three aspects of hardened steel mold,the dynamic characteristics of the machining system,the dynamic milling process dynamics modeling and the milling stability analysis. In the aspect of dynamic characteristics of hardened steel mold machining system,hammer mode test,admittance coupling substructure analysis method and the basic principles,practical applications and limitations of analytical method are mainly described. In the aspect of the dynamic milling process dynamics modeling,the dynamic cutting thickness modeling of complex surface of hardened steel mold and the extraction method of tool-workpiece surface contact area are mainly reviewed. In the aspect of milling stability analysis,the practical application of several typical chatter stable domain prediction methods is summarized. At the same time,the article points out the existing problems of milling dynamics modeling and stability study of the complex surface of hardened steel mold. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental 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.)

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Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board 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 Oncology is the property of Chinese Journal of Oncology / Zhonghua Zhongliu Zazhi 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.)

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Copyright of Geomatics & Information Science of Wuhan University is the property of Geomatics & Information Science of Wuhan 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 Natural Gas Industry is the property of Natural Gas Industry Journal Agency 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.)