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EXTERNALIZATION AND INTERNALIZATION OF CARDIAC ENDOTHELIN RECEPTORS DURING DIFFERENT PHASES OF SEPSIS IN RAT 被引量:1
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作者 王晓红 杨军 +4 位作者 董林旺 庞永政 苏静怡 唐朝枢 刘乃奎 《Chinese Medical Sciences Journal》 CAS CSCD 2001年第1期10-14,共5页
To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced... To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced by cecal ligation and puncture (CLP). ET1 receptor was assayed by using [125I]- ET1 binding. Marker enzyme activities, protein yield, and dry- to- wet weight ratio of cardiac membranes were measured. Results. Septic rat heart exhibited two distinct phases: an initial hyperdynamic phase( 9h after CLP; early stage of sepsis) followed by a hypodynamic (18h after CLP, late stage of sepsis) phase. [125I]- ET1 binding study showed that during early stage of sepsis, the Bmax of ET1 receptors was increased by 30% in sarcolemma but decreased by 19% in light vesicles, while during late stage of sepsis, the Bmax was decreased by 24% in sarcolemma but increased by 38% in light vesicles.The total binding of sarcolemma and light vesicles was increased by 25% during early stage of sepsis but decreased by 17% during late stage of sepsis. Conclusions. These data indicated that ET1 receptors in the rat heart were externalized from light vesicles to sarcolemmal membranes during early hyperdynamic phase while internalized from surface membranes to intracellular compartment during late hypodynamic phase of sepsis. 展开更多
关键词 endothelial receptor SEPSIS externalization INTERNALIZATION
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Active greeting technique: a mother-and-child catheter based technique to facilitate retrograde wire externalization in recanalization of coronary chronic total occlusion 被引量:12
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作者 Junbo Ge Lei Ge +6 位作者 Bin Zhang Xin Zhong Jianying Ma Leisheng Ru Tao Hu Juying Qian 《Science Bulletin》 SCIE EI CAS CSCD 2018年第23期1565-1569,共5页
Although retrograde approach has greatly improved the success rate of percutaneous coronary intervention(PCI) for coronary chronic total occlusion(CTO), retrograde wire externalization still remains challenging and ti... Although retrograde approach has greatly improved the success rate of percutaneous coronary intervention(PCI) for coronary chronic total occlusion(CTO), retrograde wire externalization still remains challenging and time-consuming in some cases. Cases utilizing ‘‘Active Greeting Technique(AGT)", a mother-and-child catheter based technique to facilitate retrograde wire externalization, were extracted from Chronic Total Occlusion Club, China(CTOCC) database. AGT was performed by deep intubation a mother-and-child catheter(GuidezillaTMextension, 4 or 5 Fr inner catheter, and etc.) in combination with either reverse controlled antegrade or retrograde subintimal tracking(CART) technique or retrograde wire crossing technique. A total of 111 patients with 112 CTO lesions treated with this technique were retrospectively analyzed. Reverse CART technique and retrograde wire crossing technique were performed in 90.2% and 9.8% of all procedures. The utilization of GuidezillaTMextension, 4 Fr, and 5 Fr inner catheter accounted for 94.6%, 3.6%, and 1.8%, respectively. Externalization of retrograde wire was successful in all cases. No procedural complications were adjudicated to AGT. Complications independent of AGT included two target vessel perforations and two collateral perforations. No in-hospital major adverse cardiac events were found. AGT is a feasible and safe technique that facilitates retrograde wire externalization. 展开更多
关键词 Percutaneous CORONARY intervention Chronic total occlusion RETROGRADE WIRE externalization Active GREETING TECHNIQUE
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Sound image externalization for headphone based real-time 3D audio
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作者 Yougen YUAN Lei XIE +2 位作者 Zhong-Hua FU Ming XU Qi CONG 《Frontiers of Computer Science》 SCIE EI CSCD 2017年第3期419-428,共10页
3D audio effects can provide immersive auditory experience, but we often face the so-called in-head localization (IHL) problem in headphone sound reproduction. To ad- dress this problem, we propose an effective soun... 3D audio effects can provide immersive auditory experience, but we often face the so-called in-head localization (IHL) problem in headphone sound reproduction. To ad- dress this problem, we propose an effective sound image externalization approach. Specifically, we consider several important factors related to sound propagation, which include image-source model based early reflections with distance decay, wall absorption and air absorption, late reverberation and other dynamic factors like head movement. We apply our sound image externalization approach to a headphone based real-time 3D audio system. Subjective listening tests show that the sound image externalization performance is significantly improved and the sound source direction is preserved as well. A/B preference test further shows that, as compared with a recent popular approach, the proposed approach is mostly preferred by the listeners. 展开更多
关键词 3D audio in-head localization (IHL) headphone reproduction sound image externalization REFLECTIONS
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Externalization and internalization of cardiac endothelin receptors during different phases of sepsis in rat
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作者 王晓红 杨军 +4 位作者 董林旺 庞永政 苏静怡 唐朝枢 刘乃奎 《Chinese Medical Journal》 SCIE CAS CSCD 1999年第8期66-66,共1页
Objective To study the redistribution of ET1 receptors in two subcellular organelles, the sarcolemmal membrane and the light vesicle, of rat heart during the progress of septic shock Methods Male Sprague Dawley ... Objective To study the redistribution of ET1 receptors in two subcellular organelles, the sarcolemmal membrane and the light vesicle, of rat heart during the progress of septic shock Methods Male Sprague Dawley rats weighing from 270 to 320?g were randomly divided into three groups: control, early sepsis, and late sepsis Each group included six rats Sepsis was induced by cecal ligation and puncture (CLP) Control rats were sham operated After operation for 9 hours or 18 hours, animals of the three groups were anesthetized with sodium pentobarbital (60?mg/kg IP) and the hearts were removed for preparation of sarcolemma and light vesicle Hemodynamic parameters were determined with polygraph via femoral artery and intraventricular cannula ET1 receptor was assayed by [ 125 I] ET1 binding Results Heart rate, cardiac output and left ventricular +dp/dt max undergo biphasic changes: an increase in early phase of sepsis (9?h after CLP) followed by a decrease in late phase of sepsis (18?h after CLP) Mean arterial blood pressure and left ventricular dp/dt max remained relatively unaltered during early phase of sepsis but was decreased during late phase of sepsis Although septic rat heart exhibited biphasic cardiodynamic changes, myocardial function showed signs of progressive deterioration during the development of sepsis, as indicated by a progressive elevation of LVEDP [ 125 I] ET1 bindings to cardiac membranes exhibited a saturable process with a single component binding characteristic for all three experimental groups In sarcolemmal membrane fraction, the maximum binding capacity (B max ) calculated from scatchard plot was increased 30% ( P <0 01) during early phase of sepsis but decreased 24% ( P <0 01) during late phase of sepsis The affinity [the reciprocal of the dissociation contant (Kd)] for [ 125 I] ET1 binding in sarcolemmal membranes remained unaffected during early and late phases of sepsis In light vesicle fraction, the B max for [ 125 I] ET1 binding was decreased by 19% ( P <0 05) during early phase of sepsis but increased by 38% ( P <0 01) during late phase of sepsis The affinity for [ 125 I] ET1 binding in light vesicles was unaltered in early and late phases of sepsis It should be mentioned that the sum of Bmax of sarcolemmal and light vesicle fractions was increased by 25% ( P <0 01) during early phase of sepsis but was decreased by 17% ( P <0 01) during late phase of sepsis Conclusions These data indicated that a biphasic intracellular redistribution of ET1 receptor in the heart might contribute to the development of the initial hyperdynamic and subsequent hypodynamic state during sepsis 展开更多
关键词 externalization and internalization of cardiac endothelin receptors during different phases of sepsis in rat
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GPU‑accelerated Monte Carlo method for dose calculation of mesh‑type computational phantoms
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作者 Shu‑Chang Yan Rui Qiu +3 位作者 Xi‑Yu Luo An‑Kang Hu Zhen Wu Jun‑Li Li 《Nuclear Science and Techniques》 2026年第1期297-308,共12页
Computational phantoms play an essential role in radiation dosimetry and health physics.Although mesh-type phantoms offer a high resolution and adjustability,their use in dose calculations is limited by their slow com... Computational phantoms play an essential role in radiation dosimetry and health physics.Although mesh-type phantoms offer a high resolution and adjustability,their use in dose calculations is limited by their slow computational speed.Progress in heterogeneous computing has allowed for substantial acceleration in the computation of mesh-type phantoms by utilizing hardware accelerators.In this study,a GPU-accelerated Monte Carlo method was developed to expedite the dose calculation for mesh-type computational phantoms.This involved designing and implementing the entire procedural flow of a GPUaccelerated Monte Carlo program.We employed acceleration structures to process the mesh-type phantom,optimized the traversal methodology,and achieved a flattened structure to overcome the limitations of GPU stack depths.Particle transport methods were realized within the mesh-type phantom,encompassing particle location and intersection techniques.In response to typical external irradiation scenarios,we utilized Geant4 along with the GPU program and its CPU serial code for dose calculations,assessing both computational accuracy and efficiency.In comparison with the benchmark simulated using Geant4 on the CPU using one thread,the relative differences in the organ dose calculated by the GPU program predominantly lay within a margin of 5%,whereas the computational time was reduced by a factor ranging from 120 to 2700.To the best of our knowledge,this study achieved a GPU-accelerated dose calculation method for mesh-type phantoms for the first time,reducing the computational time from hours to seconds per simulation of ten million particles and offering a swift and precise Monte Carlo method for dose calculation in mesh-type computational phantoms. 展开更多
关键词 GPU Monte Carloference Mesh-type phantom External exposure Heterogeneous
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Controlling externally solidified crystals and porosity for enhancing mechanical properties of a die-casting aluminum-silicon alloy
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作者 Yi-hui Zhang Xiang-yi Jiao +6 位作者 Peng-yue Wang Yi-xian Liu Jin-rui Wang Wen-ning Liu Li-jun Shi Cheng-gang Wang Shou-mei Xiong 《China Foundry》 2026年第1期94-100,共7页
The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-cast... The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-casting research.In this work,the combined effect of shot sleeve materials and slow shot speeds on porosity,microstructure and mechanical properties of a newly designed HPDC Al-Si alloy was investigated.Results show that employing a ceramic shot sleeve or increasing the slow shot speed significantly reduces both the average size and area fraction of externally solidified crystals(ESCs),as well as the average pore size and volume fraction.When the slow shot speed is increased from 0.05 m·s^(-1)to 0.1 m·s^(-1),the pore volume fraction decreases by 10.2%in steel-shot-sleeve samples,compared to a substantial 67.1%reduction in ceramic-shot-sleeve samples.At a slow shot speed of 0.1 m·s^(-1),castings produced with a ceramic shot sleeve exhibit superior mechanical properties:8.3%higher yield strength,17.4%greater tensile strength,and an 81.4%improvement in elongation,relative to those from a steel shot sleeve.These findings provide valuable insights for minimizing porosity and coarse ESCs in die castings,offering promising potential for broader industrial applications. 展开更多
关键词 high pressure die casting aluminum-silicon alloy externally solidified crystals POROSITY shot sleeve
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Extreme Attitude Prediction of Amphibious Vehicles Based on Improved Transformer Model and Extreme Loss Function
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作者 Qinghuai Zhang Boru Jia +3 位作者 Zhengdao Zhu Jianhua Xiang Yue Liu Mengwei Li 《哈尔滨工程大学学报(英文版)》 2026年第1期228-238,共11页
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili... Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics. 展开更多
关键词 Amphibious vehicle Attitude prediction Extreme value loss function Enhanced transformer architecture External information embedding
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Influence of mold wall thickness on morphologies of defect band in high-pressure die casting technology
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作者 Zhen-yu Sun Wen-bo Yu +4 位作者 Jun-jie Li Wei-chen Zheng Guang-rui Wang Jian-ru Fang Shou-mei Xiong 《China Foundry》 2026年第1期31-36,共6页
In order to investigate the effect of die wall thickness on morphologies of defect band,a stepped mold with a wall thickness of 5 mm,4 mm,3 mm,2 mm,and 1 mm was designed to carry out high pressure die casting experime... In order to investigate the effect of die wall thickness on morphologies of defect band,a stepped mold with a wall thickness of 5 mm,4 mm,3 mm,2 mm,and 1 mm was designed to carry out high pressure die casting experiments with AlSi10 MgMn alloy.For castings with wall thickness of 2-4 mm,the ratio of the mean defect band width(w)and mean grain size(d)in the defect band(w/d)ranges 7-18,while it increases to 24.47 for the 5 mm-thick casting.This difference is related with the filling speed and the distribution of externally solidified crystals(ESCs).The mold flow analysis indicates that the filling speed decreases from 25.41 m·s^(-1)to 11.07 m·s^(-1)when wall thickness increases from 2 mm to 5 mm.Due to the decreasing filling speed along the wall thickness,ESCs gradually diffuse from the center to the defect band,which keep the shear strength in the defect band at a high-level during filling.Meanwhile,the shear strength generated during the filling also decreases as the shear rate drops.Finally,the defect bands in the 5 mm-thick region become widen and indistinct,and the porosity is as high as 5.25%. 展开更多
关键词 AlSi10MgMn high pressure die casting defect band mold flow analysis externally solidified crystals
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A review of electroslag remelting composite technologies
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作者 Yu Wang Yan-chun Lou +5 位作者 Fang Wang Heng Cao Yun-bao Gao Ling Zhao Zhi Han Meng Li 《China Foundry》 2026年第1期1-19,共19页
Electroslag remelting(ESR) is an important metallurgical process for producing high-purity materials with homogeneous compositions and sound microstructures,and its typical products are ingots or simple castings.The c... Electroslag remelting(ESR) is an important metallurgical process for producing high-purity materials with homogeneous compositions and sound microstructures,and its typical products are ingots or simple castings.The core principle involves the resistive melting of a consumable electrode within a slag pool,followed by the refining of molten metal droplets as they traverse the slag,and subsequent sequential solidification in a water-cooled mold.However,conventional ESR processes face limitations in producing large or complex-shaped components,enhancing production efficiency,achieving highly specialized microstructures,and meeting ultra-high purity demands for advanced applications.Advanced composite ESR technologies have been developed to overcome these limitations by innovatively modifying key process aspects.For instance,electrode systems are improved using vibration,rotation,or multiple electrodes.Enhanced mold design and solidification control are achieved through techniques including conductive molds,mold rotation,and ingot withdrawal.Precise control of the process is realized through the use of protective gas,vacuum,or elevated pressure,as well as the application of external fields such as magnetic fields or ultrasonic vibration.This review comprehensively summarizes these advanced techniques,examining their principles and characteristics,and discussing their specific advantages and challenges. 展开更多
关键词 electroslag remelting(ESR) composite electroslag technology near-net shape casting high purity materials process modification external field assisted casting
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Research status of high efficiency deep penetration welding of medium-thick plate titanium alloy:A review 被引量:4
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作者 Zhihai Dong Ye Tian +4 位作者 Long Zhang Tong Jiang Dafeng Wang Yunlong Chang Donggao Chen 《Defence Technology(防务技术)》 2025年第3期178-202,共25页
Titanium alloy has the advantages of high strength,strong corrosion resistance,excellent high and low temperature mechanical properties,etc.,and is widely used in aerospace,shipbuilding,weapons and equipment,and other... Titanium alloy has the advantages of high strength,strong corrosion resistance,excellent high and low temperature mechanical properties,etc.,and is widely used in aerospace,shipbuilding,weapons and equipment,and other fields.In recent years,with the continuous increase in demand for medium-thick plate titanium alloys,corresponding welding technologies have also continued to develop.Therefore,this article reviews the research progress of deep penetration welding technology for medium-thick plate titanium alloys,mainly covering traditional arc welding,high-energy beam welding,and other welding technologies.Among many methods,narrow gap welding,hybrid welding,and external energy field assistance welding all contribute to improving the welding efficiency and quality of medium-thick plate titanium alloys.Finally,the development trend of deep penetration welding technology for mediumthick plate titanium alloys is prospected. 展开更多
关键词 Titanium alloy Deep penetration welding Narrow gap welding Hybrid welding External energy field assistance welding
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Dynamic Behavior of a Pipe Conveying a Gas-Liquid Two-Phase Flow Under External Excitations 被引量:1
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作者 FU Guang-ming WANG Xiao +4 位作者 JIAO Hui-lin WANG Bo-ying SHAN Zheng-feng SUN Bao-jiang SU Jian 《China Ocean Engineering》 2025年第5期822-838,共17页
This work investigated the dynamic behavior of vertical pipes conveying gas-liquid two-phase flow when subjected to external excitations at both ends.Even with minimal excitation amplitude,resonance can occur when the... This work investigated the dynamic behavior of vertical pipes conveying gas-liquid two-phase flow when subjected to external excitations at both ends.Even with minimal excitation amplitude,resonance can occur when the excitation frequency aligns with the natural frequency of the pipe,significantly increasing the degree of operational risk.The governing equation of motion based on the Euler-Bernoulli beam is derived for the relative deflection with stationary simply supported ends,with the effects of the external excitations represented by source terms distributed along the pipe length.The fourth-order partial differential equation is solved via the generalized integral transform technique(GITT),with the solution successfully verified via comparison with results in the literature.A comprehensive analysis of the vibration phenomena and changes in the motion state of the pipe is conducted for three classes of external excitation conditions:same frequency and amplitude(SFSA),same frequency but different amplitudes(SFDA),and different frequencies and amplitudes(DFDA).The numerical results show that with increasing gas volume fraction,the position corresponding to the maximum vibration displacement shifts upward.Compared with conditions without external excitation,the vibration displacement of the pipe conveying two-phase flow under external excitation increases significantly.The frequency of external excitation has a significant effect on the dynamic behavior of a pipe conveying two-phase flow. 展开更多
关键词 pipe conveying fluid integral transform two-phase flow external excitations dynamic response forced vibrations
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Effect of Percutaneous Catheterization and Negative Pressure Drainage in the Treatment of Giant Pancreatic Pseudocyst 被引量:1
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作者 Shenglin You Hankun Yuan +5 位作者 Xijuan Tan Qiyi Luo Libai Lu Zongjiang Luo Yuan Lu Jianchu Wang 《Journal of Biosciences and Medicines》 2025年第1期77-83,共7页
Bcakground: Pancreatic pseudocyst (PPC) is a common complication arising from acute or chronic pancreatitis, trauma, or pancreatic duct obstruction. When acute fluid collection persists for 4 - 6 weeks and is encapsul... Bcakground: Pancreatic pseudocyst (PPC) is a common complication arising from acute or chronic pancreatitis, trauma, or pancreatic duct obstruction. When acute fluid collection persists for 4 - 6 weeks and is encapsulated by a fibrous wall, it is classified as a pancreatic pseudocyst. While PPC is generally asymptomatic in many patients, it can manifest with persistent abdominal pain, dyspepsia, intra-cystic infection, and potentially lead to gastrointestinal obstruction in some cases. Although smaller PPCs may resolve spontaneously, larger PPCs tend to be refractory to absorption and often necessitate surgical intervention to prevent complications such as intracystic hemorrhage. Objective: To explore the efficacy of percutaneous catheterization with negative pressure in the treatment of large pancreatic pseudocysts. Methods: The cases of large pancreatic pseudocysts treated in our hospital from 2004 to 2022 were retrospectively collected, and the general condition, operation time, drainage time, feeding time, postoperative complications, hospital stay, cost and follow-up of the patients were analyzed. Results: A total of 132 patients with large pancreatic pseudocysts were collected. The average operation time was 32.4 ± 2.1 min;The retention time of the drainage tube was 30 ± 1.8 days in the percutaneous negative pressure drainage group;The postoperative feeding time was no fasting after local anesthesia drainage;Postoperative complications (bleeding, infection, pancreatic leakage, recurrence, anastomotic leakage, etc.): Two of the 132 patients had recurrent cysts, which were cured by re-puncture and negative pressure drainage. The length of hospital stay was 6 ± 1.1 days;The cost was 11,200 ± 1300 yuan;Follow-up: The follow-up time ranged from 1 to 3 years, and the patients had no discomfort. Conclusion: Percutaneous catheterization and negative pressure drainage can effectively treat large pancreatic pseudocysts. Compared with other treatment methods, it is simple and effective, the postoperative recovery of patients is faster, the physical damage is less, the hospital stay is shorter, and the cost is lower. 展开更多
关键词 Giant Pancreatic Pseudocyst Percutaneous External Drainage Treatment Method
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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy
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作者 Junjie Li Wenbo Yu +5 位作者 Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期147-153,共7页
High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress aro... High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated die-castings.Herein,the development of non-heat treatment Al alloys is becoming the hot topic.In addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of castings.To achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and Ce.Their influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic simulation.Our results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased porosity.Meanwhile,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical properties.Subsequent introduction of Ce resulted in the poisoning effect and reduced mechanical properties. 展开更多
关键词 aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment
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Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography
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作者 WU Min CAO Kailei +4 位作者 XIAO Weirong YU Zetai CAO Jierong DING Qingjun LI Jinhui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期164-170,共7页
The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an ... The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution. 展开更多
关键词 CONCRETE external sulfate attack damage evolution situ X-ray computed tomography
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Nonlinear Dynamic Modeling of Steel Catenary Risers with Varying Curvatures Under Internal Flow and External Current Excitation 被引量:1
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作者 LI Fang-qiu CHENG Hao +4 位作者 LIU Miao-er LI Xin-xin AN Chen LU Hai-long LU Zhao-kuan 《China Ocean Engineering》 2025年第5期904-916,共13页
As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.Thi... As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.This work establishes a dynamic behavior model of steel catenary risers(SCRs)with varying curvatures subjected to internal flow and external currents and considers the effects of pipe-soil interactions on the curvature profile.The governing equation is solved via the generalized integral transform technique(GITT),which yields a semi-analytical solution of a high-order nonlinear partial differential equation.Parametric studies are then performed to analyze the effects of varying curvature on the vibration frequency and amplitude of SCRs.The vibration frequency and amplitude increase with the touchdown angle and hang-off angle,although the effect of the hang-off angle is negligible.Additionally,as the curvature increases along the centerline axis,the position of the maximum amplitude of the SCR moves upward. 展开更多
关键词 steel catenary riser(SCR) CURVATURE generalized integral transform technique(GITT) dynamic behav-ior internal flow and external current
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Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test
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作者 Skyla Stifter Jessie McCaffrey +2 位作者 Tyler Nichols Ayse Ozcan Edeer Justine Ward 《World Journal of Methodology》 2025年第1期95-104,共10页
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor... BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing. 展开更多
关键词 External cue Internal cue Muscle activation Core muscles Lumbopelvic stability Pressure biofeedback unit
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Major injury of the external iliac artery during robotic nephroureterectomy:Examining the surgical management and unexpected pathology finding
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作者 Riccardo Bertolo Luca Roggero +11 位作者 Claudio Brancelli Giovanni Corghi Filippo Migliorini Alessandro Veccia Luca Mezzetto Gian Franco Veraldi Anna Caliò Matteo Brunelli Guido Martignoni Antonio Benito Porcaro Maria Angela Cerruto Alessandro Antonelli 《Asian Journal of Urology》 2025年第2期275-277,共3页
Dear Editor,We aimed to describe the management of the intraoperative injury of the right external iliac artery that occurred during robot-assisted right nephroureterectomy with bladder cuff excision.Surgery was sched... Dear Editor,We aimed to describe the management of the intraoperative injury of the right external iliac artery that occurred during robot-assisted right nephroureterectomy with bladder cuff excision.Surgery was scheduled for suspected urothelial carcinoma of the distal ureter in a 60-year-old woman.The patient involved in the present research signed a dedicated form to consent to the publication of images and/or information about her.Past medical history included Brugada syndrome diagnosed in 2015,and hypercholesterolemia.Past surgical history included one cesarean section only.Family history included ovarian cancer(sister),colorectal cancer(mother),and kidney cancer(father). 展开更多
关键词 urothelial carcinoma right external iliac artery external iliac artery injury dedicated form unexpected pathology brugada syndrome surgical management robotic nephroureterectomy
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Exploration of evaluation criteria based on the biological variation in the external quality assessment for basic semen analysis in China
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作者 Xi-Yan Wu Jin-Chun Lu +6 位作者 Xin-Hua Peng Jing-Liang He Dao Wang Cong-Ling Dai Wen-Bing Zhu Gang Liu Wei-Na Li 《Asian Journal of Andrology》 2025年第5期621-626,共6页
This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in t... This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in the Hunan Province(China)in 2022 and searched for data in the published literature from January2000 to December 2023 in China.On the basis of these data,we analyzed the coefficients of variation and acceptable biases of different quality control materials for basic semen analysis through robust statistics.We compared these findings with quality specifications based on biological variation from optimal,desirable,and minimum levels of bias to seek a unified and more suitable semen EQAbias evaluation standard for China's national conditions.Different sources of semen quality control material exhibited considerable variation in acceptable biases among laboratories,ranging from 8.2%to 56.9%.A total of 50.0% of the laboratories met the minimum quality specifications for progressive motility(PR),whereas 100.0%and 75.0%of laboratories met only the minimum quality specifications for sperm concentration and total motility(nonprogressive[NP]+PR),respectively.The Z value for sperm concentration and PR+NP was equivalent to the desirable performance specification,whereas the Z value for PR was equivalent only to the minimum performance specification.This study highlights the feasibility of operating external quality assessment schemes for basic semen analysis using quality specifications based on biological variation.These specifications should be unified among external quality control(EQC)centers based on biological variation. 展开更多
关键词 acceptable bias biological variation external quality assessment(EQA) external quality control(EQC) semen testing
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Comparison of the quality of chest compressions during cardiopulmonary resuscitation with two models of automated external defibrillators:a manikin-based randomized trial
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作者 Arnaud Gaillard Cécile Ricard +1 位作者 Guillaume Berthet Vincent Peigne 《World Journal of Emergency Medicine》 2025年第4期374-377,共4页
Basic life support for cardiac arrest associates cardiopulmonary resuscitation(CPR)and defibrillation.CPR relies on chest compressions(CC)and ventilation.Current guidelines on CPR recommend a depth of 5-6 cm at a rhyt... Basic life support for cardiac arrest associates cardiopulmonary resuscitation(CPR)and defibrillation.CPR relies on chest compressions(CC)and ventilation.Current guidelines on CPR recommend a depth of 5-6 cm at a rhythm of 100-120 times/min for CC.[1,2]Interruptions of the CC must be as short as possible and are related to ventilation,defibrillation and turnover of the rescuers.Most of the automated external defibrillators(AEDs)require interruptions of the CC to perform rhythm analysis.Among the numerous marketed models of AEDs,some provide real-time feedback about the quality of the CC. 展开更多
关键词 cardiopulmonary resuscitation cpr chest compressions cc cardiopulmonary resuscitation automated external defibrillators aeds require rhythm analysisamong chest compressions automated external defibrillators manikin based randomized trial
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Optimizing Field Taxonomy:Development of a Field-Adapted Identification Key to the Rodents of an Afromontane Tropical Rainforest
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作者 Methode Majyambere Pacifique Niyodushima Antoine Nsabimana 《Research in Ecology》 2025年第4期251-267,共17页
Identification keys for terrestrial small mammals are often based on scientific details that require close examination of museum specimens.This paper builds on external morphological characteristics of the rodents rec... Identification keys for terrestrial small mammals are often based on scientific details that require close examination of museum specimens.This paper builds on external morphological characteristics of the rodents recorded through live trapping from 2011 to 2023 in Nyungwe National Park,a tropical rainforest in Rwanda,to formulate a taxonomic key suitable for both expert and non-expert researchers working in similar ecosystems across Africa.We reviewed the literature on taxonomic keys and field guide documents for small mammals to assess their practicality and identify gaps,with a special focus on their relevance to tropical regions and our study area.We then integrated our field records to harmonize this new development.We describe 23 rodent species,identified and confirmed using advanced taxonomic techniques,including DNA barcoding and voucher specimens.The study emphasizes that external features—particularly field photographs,body coloration(dorsal,ventral,and lateral views),and other distinctive anatomical traits—can serve as an effective field taxonomic key for rodents and other terrestrial small mammals,accessible to a broad scientific community.The paper also discusses the limitations of traditional dichotomous keys compared to short descriptions paired with photographic illustrations.The resulting key can be used as a template and is open to refinement as additional species are confirmed,re-assessed,or validated through advanced tools.Future studies may adapt this approach for other terrestrial small mammals and different locations across African tropical rainforests. 展开更多
关键词 External Character Fur Color Identification Nyungwe RODENTS Tropical Forest
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