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ESMO2023:恩扎卢胺联合雄激素剥夺治疗对比安慰剂联合雄激素剥夺治疗在中国转移性激素敏感性前列腺癌患者中的疗效和安全性(中国ARCHES)
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作者 李永红 《现代泌尿外科杂志》 2024年第1期81-82,共2页
2019年发表的全球ARCHES试验(NCT02677896)结果显示,与安慰剂(placebo,PBO)+雄激素剥夺治疗(androgen deprivation therapy,ADT)相比,恩扎卢胺+ADT延长了转移性激素敏感性前列腺癌(metastatic hormone-sensitive prostate cancer,mHSPC... 2019年发表的全球ARCHES试验(NCT02677896)结果显示,与安慰剂(placebo,PBO)+雄激素剥夺治疗(androgen deprivation therapy,ADT)相比,恩扎卢胺+ADT延长了转移性激素敏感性前列腺癌(metastatic hormone-sensitive prostate cancer,mHSPC)患者的总生存期和放射影像学无进展生存期(radiographic progression-free survival,rPFS)^([1])。然而,该试验无中国患者入组。欧洲肿瘤内科学会(European Society for Medical Oncology,ESMO)2023年会议报道了中国ARCHES研究(NCT04076059)的初步结果,这是一项评估恩扎卢胺+ADTvs.PBO+ADT在中国m HSPC患者中的疗效和安全性的多中心、随机、双盲、PBO对照的Ⅲ期试验^([2])。 展开更多
关键词 转移性激素敏感性前列腺癌 恩扎卢胺 雄激素剥夺治疗 安慰剂 中国患者 archES
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Recent Construction Technology Innovations and Practices for Large-Span Arch Bridges in China
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作者 Jielian Zheng 《Engineering》 SCIE EI CAS CSCD 2024年第10期110-129,共20页
Arch bridges provide significant technical and economic benefits under suitable conditions.In particular,concrete-filled steel tubular(CFST)arch bridges and steel-reinforced concrete(SRC)arch bridges are two types of ... Arch bridges provide significant technical and economic benefits under suitable conditions.In particular,concrete-filled steel tubular(CFST)arch bridges and steel-reinforced concrete(SRC)arch bridges are two types of arch bridges that have gained great economic competitiveness and span growth potential due to advancements in construction technology,engineering materials,and construction equipment over the past 30 years.Under the leadership of the author,two record-breaking arch bridges—that is,the Pingnan Third Bridge(a CFST arch bridge),with a span of 560 m,and the Tian’e Longtan Bridge(an SRC arch bridge),with a span of 600 m—have been built in the past five years,embodying great technological breakthroughs in the construction of these two types of arch bridges.This paper takes these two arch bridges as examples to systematically summarize the latest technological innovations and practices in the construction of CFST arch bridges and SRC arch bridges in China.The technological innovations of CFST arch bridges include cable-stayed fastening-hanging cantilevered assembly methods,new in-tube concrete materials,in-tube concrete pouring techniques,a novel thrust abutment foundation for nonrocky terrain,and measures to reduce the quantity of temporary facilities.The technological innovations of SRC arch bridges involve arch skeleton stiffness selection,the development of encasing concrete materials,encasing concrete pouring,arch rib stress mitigation,and longitudinal reinforcement optimization.To conclude,future research focuses and development directions for these two types of arch bridges are proposed. 展开更多
关键词 Concrete-filled steel tubular arch bridges Steel-reinforced concrete arch bridges Cable-stayed fastening-hanging cantilevered assembly Non-rocky thrust abutment foundation Stiff skeleton Encasing concrete pouring Longitudinal reinforcement optimization
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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model
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作者 Er-feng Zhao Xin Li Chong-shi Gu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期177-186,共10页
Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and ... Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures. 展开更多
关键词 Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model
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Numerical Simulation Analysis of Welded Joints in Arch Ribs of Large Span Steel Pipe Arch Bridges
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作者 Deer He Nianchun Deng Xiuning Peng 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第3期19-30,共12页
In order to study the residual stress distribution law of welded joints of arch ribs of large-span steel pipe concrete arch bridges,numerical simulation of temperature,stress and strain fields based on ABAQUS for weld... In order to study the residual stress distribution law of welded joints of arch ribs of large-span steel pipe concrete arch bridges,numerical simulation of temperature,stress and strain fields based on ABAQUS for welded joints of arch-ribbed steel tubes using 7-,8-and 9-layer welds is carried out and its accuracy is demonstrated.The steel pipe welding temperature changes,residual stress distribution,different processes residual stress changes in the law,the prediction of post-weld residual stress distribution and deformation are studied in this paper.The results show that the temperature field values and test results are more consistent with the accuracy of numerical simulation of welding,the welding process is mainly in the form of heat transfer;Residual high stresses are predominantly distributed in the Fusion zone(FZ)and Heat-affected zone(HAZ),with residual stress levels tending to decrease from the center of the weld along the axial path,the maximum stress appears in the FZ and HAZ junction;The number of welding layers has an effect on the residual stress distribution,the number of welding layers increases,the residual stress tends to decrease,while the FZ and HAZ high stress area range shrinks;Increasing the number of plies will increase the amount of residual distortion. 展开更多
关键词 steel pipe and concrete arch bridge arch rib multi-pass welding residual stress numerical simulation
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Effects of comprehensive nursing with cognitive behavioral therapy in orthodontic osteodilated arch treatment
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作者 Xin Yang Zeng-Xiang Wang +3 位作者 Yu-Xing Tian Chao Peng Hui-Ning Yang Ying Wu 《World Journal of Clinical Cases》 SCIE 2024年第22期5051-5058,共8页
BACKGROUND This work explored the effects of cognitive behavior therapy(CBT)-based comprehensive nursing intervention(CNI)mode in arch expansion to treat patients with orthodontic osteodilated arch(OOA).AIM To explore... BACKGROUND This work explored the effects of cognitive behavior therapy(CBT)-based comprehensive nursing intervention(CNI)mode in arch expansion to treat patients with orthodontic osteodilated arch(OOA).AIM To explore the application effect of CBT-based CNI model in orthodontic expansion arch treatment.METHODS Using convenient sampling method,81 patients with OOA were selected and rolled into a control group(Ctrl group,40 cases)and an observation group(Obs group,41 cases).During the treatment,patients in the Ctrl group received routine nursing intervention mode,and the those in the Obs group received CBT mode on the basis of this.Before and after intervention,the incidence of oral mucositis,the mastery rate of correct arch expansion method,self-rating anxiety scale score,soft scale index,and plaque index were compared for patients in different groups.In addition,satisfaction and complications were comparatively analyzed.RESULTS Incidence of oral mucositis in the Obs group was lower(14.6%vs 38.5%),and the mastery rate of correct arch expansion method was obviously higher(90.2%vs 55.0%)was obviously higher(all P<0.05).Meanwhile,the soft scale index and plaque index in the Obs group were much lower(P<0.05).The compliance(90.24%)and satisfaction(95.12%)in the Obs group were greatly higher(P<0.05).CONCLUSION The CBT-based CNI mode greatly improved the mastery rate of correct arch expansion method during arch expansion in treating patients with OOA and enhanced the therapeutic effect of arch expansion and the oral health of patients,improving the patient compliance. 展开更多
关键词 Orthodontic osteodilated arch Cognitive behavior therapy Comprehensive nursing intervention mode Nursing effect Pain management Oral care
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基于SARIMA-ARCH的电量预测模型
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作者 许然 杨黎娜 钟强 《电脑与电信》 2024年第5期88-91,共4页
电量预测是供电单位购电的重要依据,是电力经济稳定运行的根本基础。提出采用SARIMA-ARCH融合模型对某地区售电量进行预测。首先,采用季节时间序列分析方法(SARIMA)对月度电量时间序列进行建模,通过ACF和PACF图筛选确定出最佳模型阶数,... 电量预测是供电单位购电的重要依据,是电力经济稳定运行的根本基础。提出采用SARIMA-ARCH融合模型对某地区售电量进行预测。首先,采用季节时间序列分析方法(SARIMA)对月度电量时间序列进行建模,通过ACF和PACF图筛选确定出最佳模型阶数,得到季节性时间序列模型(SARIMA)基础预测模型;提取模型残差的波动性,建立自回归条件异方差(ARCH)模型;最后,将SARIMA-ARCH模型与常规SRIAM和ARIMA的预测值进行对比分析。结果表明,SARIMAARCH混合模型的预测精度较高。 展开更多
关键词 SARIMA 时间序列分析 arch效应 售电量
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基于ARCH族模型的股票超高频数据的波动性研究——以浦发银行为例
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作者 徐丹蕾 王云媛 《中小企业管理与科技》 2024年第16期56-58,共3页
论文基于浦发银行股票的逐笔交易数据,利用ARCH族模型对其超高频数据中的波动性进行了研究。论文首先通过对数据的预处理和单位根检验,确保了数据的平稳性,随后应用多种ARCH族模型对波动性进行建模与比较,最终选择TGARCH(2,1,1)模型作... 论文基于浦发银行股票的逐笔交易数据,利用ARCH族模型对其超高频数据中的波动性进行了研究。论文首先通过对数据的预处理和单位根检验,确保了数据的平稳性,随后应用多种ARCH族模型对波动性进行建模与比较,最终选择TGARCH(2,1,1)模型作为最优模型。该模型不仅能够捕捉数据中的波动集聚效应,还揭示了显著的波动非对称性。研究结果表明,浦发银行的股票收益波动性具有显著的持久性和杠杆效应,负面冲击对波动的影响大于正面冲击。基于这些发现,论文提出了加强高频交易监管、优化投资策略和强化风险管理等政策启示。 展开更多
关键词 超高频数据 arch族模型 波动性 浦发银行
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Elastic responses of underground circular arches considering dynamic soil-structure interaction:A theoretical analysis 被引量:11
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作者 Hai-Long Chen Feng-Nian Jin Hua-Lin Fan 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第1期110-122,共13页
Due to the wide applications of arches in underground protective structures, dynamic analysis of circular arches including soil-structure interactions is important. In this paper, an exact solution of the forced vibra... Due to the wide applications of arches in underground protective structures, dynamic analysis of circular arches including soil-structure interactions is important. In this paper, an exact solution of the forced vibration of circular arches subjected to subsurface denotation forces is obtained. The dynamic soil-structure interaction is considered with the introduction of an interfacial damping between the structure element and the surrounding soil into the equa- tion of motion. By neglecting the influences of shear, rotary inertia and tangential forces and assuming the arch incompressible, the equations of motion of the buried arches were set up. Analytical solutions of the dynamic responses of the protective arches were deduced by means of modal super- position. Arches with different opening angles, acoustic impedances and rise-span ratios were analyzed to discuss their influences on an arch. The theoretical analysis suggests blast loads for elastic designs and predicts the potential failure modes for buried protective arches. 展开更多
关键词 Underground protective arches - Dynamic soilstructure interaction Dynamic responses Analytical solution
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Improved method for determining active earth pressure considering arching effect and actual slip surface 被引量:3
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作者 HE Zhong-ming LIU Zheng-fu +1 位作者 LIU Xiao-hong BIAN Han-bing 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第7期2032-2042,共11页
To determine the distribution of active earth pressure on retaining walls, a series of model tests with the horizontally translating rigid walls are designed. Particle image velocimetry is used to study the movement a... To determine the distribution of active earth pressure on retaining walls, a series of model tests with the horizontally translating rigid walls are designed. Particle image velocimetry is used to study the movement and shear strain during the active failure of soil with height H and friction angle φ. The test results show that there are 3 stages of soil deformation under retaining wall translation: the initial stage, the expansion stage and the stability stage. The stable sliding surface in the model tests can be considered to be composed of two parts. Within the height range of 0.82 H-1.0 H, it is a plane at an angle of π/4+φ/2 to the horizontal plane. In the height range of 0-0.82 H, it is a curve between a logarithmic spiral and a plane at an angle of π/4+φ/2 to the horizontal. A new method applicable to any sliding surface is proposed for active earth pressure with the consideration of arching effect. The active earth pressure is computed with the actual shape of the slip surface and compared with model test data and with predictions obtained by existing methods. The comparison shows that predictions from the newly proposed method are more consistent with the measured data than the predictions from the other methods. 展开更多
关键词 particle image velocimetry retaining wall soil arching effect active earth pressure
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Seismic response of arch dams considering infinite radiation damping and joint opening effects 被引量:2
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作者 刘新佳 徐艳杰 +1 位作者 王光纶 张楚汉 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2002年第1期65-73,共9页
Effects of two important factors on earthquake response of high arch dams are considered and combined into one program.These tactors are:effects of radiation damping of the infinite canyon and local non-linearity of t... Effects of two important factors on earthquake response of high arch dams are considered and combined into one program.These tactors are:effects of radiation damping of the infinite canyon and local non-linearity of the contraction joint opening between the dam monoliths.For modeling of rock canyon,the discrete parameters are obtained based on a curve fitting, thus allowing the nonlinear dam system to be solved in the time domain.The earthquake uniform tree-field input at the dam-canyon interface is used.An engineering example is given to demonstrate the significant effects of the radiation damping on the structure response. 展开更多
关键词 arch dams dam-canyon interaction radiation damping joint opening ocal nonlinearity
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Pile-soil stress ratio in bidirectionally reinforced composite ground by considering soil arching effect 被引量:1
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作者 邹新军 杨眉 +1 位作者 赵明华 杨小礼 《Journal of Central South University》 SCIE EI CAS 2008年第S2期1-7,共7页
To discuss the soil arching effect on the load transferring model and sharing ratios by the piles and inter-pile subsoil in the bidirectionally reinforced composite ground, the forming mechanism, mechanical behavior a... To discuss the soil arching effect on the load transferring model and sharing ratios by the piles and inter-pile subsoil in the bidirectionally reinforced composite ground, the forming mechanism, mechanical behavior and its effect factors were discussed in detail. Then, the unified strength theory was introduced to set up the elastoplastic equilibrium differential equation of the subsoil under the limit equilibrium state. And from the equation, the solutions were derived with the corresponding formulas presented to calculate the earth pressure over and beneath the horizontal reinforced cushion or pillow, the stress of inter-pile subsoil and the pile-soil stress ratio. Based on the obtained solutions and measured data from an engineering project, the influence rules by the soil property parameters (i.e., the cohesion c and internal friction angle φ) and pile spacing on the pile-soil stress ratio n were discussed respectively. The results show that to improve the load sharing ratio by the piles, the more effective means for filling materials with a larger value of φ is to increase the ratio of pile cap size to spacing, while to reduce the pile spacing properly and increase the value of cohesion c is advisable for those filling materials with a smaller value of φ. 展开更多
关键词 composite ground PILE geosynthetic-reinforced CUSHION soil archING effect PILE-SOIL stress ratio
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Stability and reinforcement analyses of high arch dams by considering deformation effects 被引量:1
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作者 Qiang Yang Yaoru Liu +1 位作者 Yingru Chen Weiyuan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2010年第4期305-313,共9页
The strict definition and logical description of the concept of structure stability and failure are presented. The criterion of structure stability is developed based on plastic complementary energy and its variation.... The strict definition and logical description of the concept of structure stability and failure are presented. The criterion of structure stability is developed based on plastic complementary energy and its variation. It is presented that the principle of minimum plastic complementary energy is the combination of structure equilibrium, coordination condition of deformation and constitutive relationship. Based on the above arguments, the deformation reinforcement theory is developed. The structure global stability can be described by the relationship between the global degree of safety of structure and the plastic complementary energy. Correspondingly, the new idea is used in the evaluations of global stability, anchorage force of dam-toe, fracture of dam-heel and treatment of faults of high arch dams in China. The results show that the deformation reinforcement theory provides a uniform and practical theoretical framework and a valuable solution for the analysis of global stability, dam-heel cracking, dam-toe anchorage and reinforcement of faults of high arch dams and their foundations. 展开更多
关键词 deformation reinforcement theory structure stability unbalanced force plastic complementary energy high arch dams
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Endovascular repair of thoracic aortic dissection associated with right-sided aortic arch:report of four cases 被引量:1
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作者 Ye Yuan Yi Zhao +1 位作者 Mi Zhang Huijun Lu 《The Journal of Biomedical Research》 CAS CSCD 2017年第1期74-78,共5页
Aortic dissection involving a right-sided aortic arch(RAA)is extremely rare with an incidence in adults of 0.04%to 0.1%^([1]).Thoracic aortic dissection associated with RAA is even a more uncommon and life-threate... Aortic dissection involving a right-sided aortic arch(RAA)is extremely rare with an incidence in adults of 0.04%to 0.1%^([1]).Thoracic aortic dissection associated with RAA is even a more uncommon and life-threatening condition.For complicated aortic dissection,conventional open surgical repair is considered a standard therapy^([2]).However, 展开更多
关键词 Endovascular repair of thoracic aortic dissection associated with right-sided aortic arch RAA RCCA
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Mechanical properties and influence mechanism of confined concrete arches in high-stress tunnels 被引量:9
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作者 Bei Jiang Zhongxin Xin +4 位作者 Xiufeng Zhang Yusong Deng Mingzi Wang Shidong Li Wentao Ren 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第7期829-841,共13页
Deep underground projects(e.g., coal mines), are often faced with complex conditions such as high stress and extremely soft rock. The strength and rigidity of the traditional support system are often insufficient,whic... Deep underground projects(e.g., coal mines), are often faced with complex conditions such as high stress and extremely soft rock. The strength and rigidity of the traditional support system are often insufficient,which makes it difficult to meet the requirements of ground control under complex conditions. As a new support form with high strength and rigidity, the confined concrete arch plays an important role in controlling the rock deformation under complex conditions. The section shape of the tunnel has an important impact on the mechanical properties and design of the support system. However, studies on the mechanical properties and influence mechanism of the new confined concrete arch are rarely reported. To this end, the mechanical properties of traditional U-shaped steel and new confined concrete arches are compared and comparative tests on arches of circular and straight-leg semicircular shapes in deep tunnels are conducted. A large mechanical testing system for underground engineering support structure is developed. The mechanical properties and influence mechanism of confined concrete arches with different section shapes under different loading modes and cross-section parameters are systematically studied. Test results show that the bearing capacity of the confined concrete arch is 2.10 times that of the U-shaped steel arch, and the bearing capacity of the circular confined concrete arch is 2.27 times that of the straight-leg semicircular arch. Among the various influencing factors and their engineering parameters,the lateral stress coefficient has the greatest impact on the bearing capacity of the confined concrete arch,followed by the steel pipe wall thickness, steel strength, and core concrete strength. Subsequently, the economic index of bearing capacity and cost is established, and the optimization design method for the confined concrete arch is proposed. Finally, this design method is applied to a high-stress tunnel under complex conditions, and the deformation of the surrounding rock is effectively controlled. 展开更多
关键词 High-stress tunnel Confined concrete arch Section shape Mechanical properties Design method
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Prone-positioned upside-done arch exercise, a kind of lumbodorsal muscles training, curbs the progression of lumbar disc bulge 被引量:1
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作者 Zeng-Jie Gao Jiu-Yi Chen Yang Liu 《TMR Non-Drug Therapy》 2018年第1期9-15,共7页
Objective: To study the effects of prone-positioned upside-done arch exercise, a kind of lumbodorsal muscles training originated from Yoga, on curbing the progression of lumbar disc bulge. Methods: A total of 120 ou... Objective: To study the effects of prone-positioned upside-done arch exercise, a kind of lumbodorsal muscles training originated from Yoga, on curbing the progression of lumbar disc bulge. Methods: A total of 120 out-patients, diagnosed with lumbar disc bulge by CT and/or MRI, were randomly divided into the observation group and the control group, with 60 patients in each group. Patients in the observation group received the prone-positioned upside-done arch exercise combined with traction and acupuncture for two months and followed with a two-year treatment with prone-positioned upside-done arch exercise while the patients in the control group only received traction and acupuncture for two months. After two years, patients in both groups were investigated for the visual analogue score, MR image and straight leg raise tests. Results: Compared to the control group, prone-positioned upside-done arch exercise combined with traction and acupuncture showed significant decrease in patients’ visual analogue score, bulge size and the positive ratio of straight leg raise test (P = 0.001, P = 0.001 and P = 0.02 respectively), suggesting the inhibitory effect on the progression of lumber disc bulge. Conclusion: Prone-positioned upside-done arch has the potentials to protect patients with lumbar disc bulge from nerve root compression syndrome. 展开更多
关键词 Prone-positioned upside-done arch YOGA Lumbar disc bulge EXERCISE
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Deformation critical threshold estimation of Xiaowan ultrahigh arch dam with time-varying grey model 被引量:1
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作者 Er-feng Zhao Bo Li +1 位作者 Hao Chen Bing-bing Nie 《Water Science and Engineering》 EI CAS CSCD 2023年第3期302-312,共11页
The structural behavior of the Xiaowan ultrahigh arch dam is primarily influenced by external loads and time-varying characteristics of dam concrete and foundation rock mass during long-term operation. According to ov... The structural behavior of the Xiaowan ultrahigh arch dam is primarily influenced by external loads and time-varying characteristics of dam concrete and foundation rock mass during long-term operation. According to overload testing with a geological model and the measured time series of installed perpendicular lines, the space and time evolution characteristics of the arch dam structure were analyzed, and its mechanical performance was evaluated. Subsequently, the deformation centroid of the deflective curve was suggested to indicate the magnitude and unique distribution rules for a typical dam section using the measured deformation values at multi-monitoring points. The ellipse equations of the critical ellipsoid for the centroid were derived from the historical measured time series. Hydrostatic and seasonal components were extracted from the measured deformation values with a traditional statistical model, and residuals were adopted as a grey component. A time-varying grey model was developed to accurately predict the evolution of the deformation behavior of the ultrahigh arch dam during future operation. In the developed model, constant coefficients were modified so as to be time-dependent functions, and the prediction accuracy was significantly improved through introduction of a forgetting factor. Finally, the critical threshold was estimated, and predicted ellipsoids were derived for the Xiaowan arch dam. The findings of this study can provide technical support for safety evaluation of the actual operation of ultrahigh arch dams and help to provide early warning of abnormal changes. 展开更多
关键词 arch dam Deformation behavior EVOLUTION Critical threshold Grey model
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Structural Damage Identification System Suitable for Old Arch Bridge in Rural Regions: Random Forest Approach 被引量:1
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作者 Yu Zhang Zhihua Xiong +2 位作者 Zhuoxi Liang Jiachen She Chicheng Ma 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期447-469,共23页
A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of ... A huge number of old arch bridges located in rural regions are at the peak of maintenance.The health monitoring technology of the long-span bridge is hardly applicable to the small-span bridge,owing to the absence of technical resources and sufficient funds in rural regions.There is an urgent need for an economical,fast,and accurate damage identification solution.The authors proposed a damage identification system of an old arch bridge implemented with amachine learning algorithm,which took the vehicle-induced response as the excitation.A damage index was defined based on wavelet packet theory,and a machine learning sample database collecting the denoised response was constructed.Through comparing three machine learning algorithms:Back-Propagation Neural Network(BPNN),Support Vector Machine(SVM),and Random Forest(R.F.),the R.F.damage identification model were found to have a better recognition ability.Finally,the Particle Swarm Optimization(PSO)algorithm was used to optimize the number of subtrees and split features of the R.F.model.The PSO optimized R.F.model was capable of the identification of different damage levels of old arch bridges with sensitive damage index.The proposed framework is practical and promising for the old bridge’s structural damage identification in rural regions. 展开更多
关键词 Old arch bridge damage identification machine learning random forest particle swarm optimization
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Improved super-elastic Ti–Ni alloy wire intrusion arch for skeletal class Ⅱ malocclusion combined with deep overbite:A case report 被引量:1
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作者 Ching-Yu Yang Chih-Chieh Lin +2 位作者 I-Jia Wang Yuan-Hou Chen Jian-Hong Yu 《World Journal of Clinical Cases》 SCIE 2023年第17期4142-4151,共10页
BACKGROUND Treatment for deep overbite cases can be difficult. This case report presents some techniques with improved super-elastic Ti–Ni alloy wire(ISW) for deep overbite correction.CASE SUMMARY A 21-year-old woman... BACKGROUND Treatment for deep overbite cases can be difficult. This case report presents some techniques with improved super-elastic Ti–Ni alloy wire(ISW) for deep overbite correction.CASE SUMMARY A 21-year-old woman had a chief complaint of flaring maxillary teeth. Orthodontic evaluation revealed a skeletal class Ⅱ malocclusion and a convex profile appearance. A deep overbite with palatal impingement and large overjet were also noted. Bilateral maxillary first premolars were extracted, and spaces were closed using a closed-coil spring and elastic chain. The deep overbite was corrected by applying the ISW curve and ISW intrusion arch. Intermaxillary elastics was used to adjust the intermaxillary relationship. Active treatment took approximately 3 years, and the appearance and dentition alignment noticeably improved.CONCLUSION The use of the ISW technique in a case of skeletal class Ⅱ malocclusion with deep overbite achieved a desirable result, and the patient was satisfied with the treatment outcome. 展开更多
关键词 Dentistry ORTHODONTICS Skeletal class II Intrusion arch Case report
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Finite element model for arch bridge vibration dynamics considering effect of suspender length adjustment on geometry stiffness matrix
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作者 钟轶峰 《Journal of Chongqing University》 CAS 2006年第4期218-222,共5页
In this paper, we established a finite element (FEM) model to analyze the dynamic characteristics of arch bridges. In this model, the effects of adjustment to the length of a suspender on its geometry stiffness matrix... In this paper, we established a finite element (FEM) model to analyze the dynamic characteristics of arch bridges. In this model, the effects of adjustment to the length of a suspender on its geometry stiffness matrix are stressed. The FEM equations of mechanics characteristics, natural frequency and main mode are set up based on the first order matrix perturbation theory. Applicantion of the proposed model to analyze a real arch bridge proved the improvement in the simulation precision of dynamical characteristics of the arch bridge by considering the effects of suspender length variation. 展开更多
关键词 finite element model SUSPENDER geometry stiffness matrix dynamic characteristic arch bridge
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Minimally Invasive Surgical Technique in Double Aortic Arch with Distal Atretic Left-Side in Infant:From a Single-Surgeon Clinical Experience
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作者 Qi Liu Shoujun Li Zhongdong Hua 《Congenital Heart Disease》 SCIE 2022年第5期533-539,共7页
Background:Double aortic arch(DAA)with distal left-sided aortic arch atresia(LAAA)can form complete vascular ring by ligamentum connection.We aimed to introduce an uncommon DAA-LAAA diagnosis and treatment by the mini... Background:Double aortic arch(DAA)with distal left-sided aortic arch atresia(LAAA)can form complete vascular ring by ligamentum connection.We aimed to introduce an uncommon DAA-LAAA diagnosis and treatment by the minimally invasive surgical technique(MIST).Methods:We retrospectively reviewed 7 cases of DAA-LAAA that were treated from January 2017 to July 2021.All infant patients underwent surgical repair by minimally invasive surgical technique.Mean follow-up was 14.43 months(range,5–21 months).Results:There were seven patients with DAA-LAAA,including six males and one female.Median age was 19.29 months(range,9.0–29.0 months).Median weight was 11.30 kg(range,9.6–13.0 kg).Three patients were found severe tracheal compression by cardiac computed tomography angiography(cCTA).Six patients with isolated DAA-LAAA were performed operations through left subaxillary minithoracotomy,and one patient with ventricular septal defect(VSD)was performed operation concurrently under the cardiopulmonary bypass(CPB)through right subaxillary minithoracotomy.All patients had symptom improvement in the postoperative period and discharged successfully.Follow-up data showed good results in short-term.Conclusions:We introduce a new surgical pathway for DAA-LAAA treatment with good symptomatic relief in short-term.MIST is a safe,feasible and economical approach for infant patients. 展开更多
关键词 Double aortic arch complete vascular ring minimally invasive surgical technique
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