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Study on the low mechanical anisotropy of extruded Mg-Zn-Mn-Ce-Ca alloy tube in the compression process 被引量:1
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作者 Dandan Li Qichi Le +6 位作者 Xiong Zhou Xiaoqiang Li Chenglu Hu Ruizhen Guo Tong Wang Ping Wang Wenxin Hu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1054-1067,共14页
In this study,the extruded Mg-Zn-Mn-Ce-Ca alloy tube with a low compression anisotropy along the ED,45ED and TD was prepared.The effect of the second phases,initial texture and deformation behavior on this low mechani... In this study,the extruded Mg-Zn-Mn-Ce-Ca alloy tube with a low compression anisotropy along the ED,45ED and TD was prepared.The effect of the second phases,initial texture and deformation behavior on this low mechanical anisotropy was investigated.The results revealed that the alloy tube contains the high content(Mg1-xZnx)11Ce phase and the low content of Mg12Ce phase.These second phases are respectively incoherent and coherent with the Mg matrix,and their influence can be ignored.Additionally,the alloy tube exhibited a weak basal fiber texture,where the c-axis was aligned along the 0°∼30°tilt from TD to ED.Such a texture made the initial deformation(at 1.0%∼1.6%strain)of the three samples controlled by comparable basalslip.As deformation progressed(1.6∼9.0%strain),larger amounts of ETWs nucleated and gradually approached saturation in the three samples,re-orienting the c-axis to a 0°∼±30°deviation with respect to the loading directions.Meanwhile,the prismatic and pyramidal<c+a>slips replaced the dominant deformation progressively until fracture.Eventually,the similar deformation mechanisms determined by the weak initial texture in the three samples contribute to the comparable strain hardening rates,resulting in the low compressive anisotropy of the alloy tube. 展开更多
关键词 Mg alloy tube Low mechanical anisotropy Weak texture Deformation mechanism.
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法舒地尔缓解β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡
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作者 郭敏芳 张慧宇 +3 位作者 章培军 苏琴 贾思玮 尉杰忠 《中国组织工程研究》 CAS 北大核心 2025年第23期4939-4946,共8页
背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH... 背景:法舒地尔对阿尔茨海默病小鼠脑内的线粒体动力学有调节作用,并且可以抑制神经炎症,但能否调节线粒体自噬和NLRP3炎症小体进而减轻β-淀粉样蛋白毒性尚不清楚。目的:探究法舒地尔对β-淀粉样蛋白1-42诱导的人源神经母细胞瘤细胞株SH-SY5Y凋亡和线粒体自噬以及NLRP3炎症小体的调节作用。方法:将SH-SY5Y细胞接种于孔板内,细胞贴壁后分3组干预:对照组不加入任何药物,模型组加入20μmol/L β-淀粉样蛋白1-42,法舒地尔组同时加入20μmol/L β-淀粉样蛋白1-42与15 mg/L法舒地尔,干预24 h后,采用MTT法检测细胞活性,TUNEL染色检测细胞凋亡,qRT-PCR和Western blot检测凋亡相关蛋白表达,免疫荧光染色和Western blot检测线粒体自噬相关蛋白表达,免疫荧光染色和Western blot检测NLRP3炎症小体相关蛋白表达。结果与结论:(1)与对照组比较,模型组细胞活性降低、凋亡率升高(P<0.05);与模型组比较,法舒地尔组细胞活性升高、凋亡率降低(P<0.05);(2)qRT-PCR和Western blot检测结果显示,与对照组比较,模型组细胞Bax mRNA与蛋白表达升高(P<0.05),Bcl-2 mRNA与蛋白表达降低(P<0.05);与模型组比较,法舒地尔组细胞Bax mRNA与蛋白表达降低(P<0.05),Bcl-2 mRNA与蛋白表达升高(P<0.05);(3)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞PINK1、帕金森病蛋白和LC3蛋白表达降低(P<0.05),p62蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞PINK1、帕金森病蛋白和LC3蛋白表达升高(P<0.05),p62蛋白表达降低(P<0.05);(4)免疫荧光染色和Western blot检测结果显示,与对照组相比,模型组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达升高(P<0.05);与模型组相比,法舒地尔组细胞NLRP3、ASC、Caspase-1和白细胞介素1β蛋白表达降低(P<0.05);(5)结果表明,法舒地尔可以减轻β-淀粉样蛋白1-42诱导的SH-SY5Y细胞凋亡,其机制可能与激活线粒体自噬且抑制NLRP3炎症小体激活有关。 展开更多
关键词 法舒地尔 Β-淀粉样蛋白 神经细胞 细胞凋亡 线粒体自噬 炎症小体
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自旋-轨道耦合作用下极化激元凝聚中的调制不稳定性
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作者 陈海军 《原子与分子物理学报》 CAS 北大核心 2025年第6期136-143,共8页
利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用... 利用线性稳定性分析方法,对存在自旋-轨道耦合(SOS)作用的二维极化激元玻色-爱因斯坦凝聚(BEC)系统中的调制不稳定性(MI)进行了研究.分析了组分内部,组分之间以及SOC相互作用对系统调制不稳定性的影响.结果显示,当系统内部不存在SOC作用,组分之间的相互作用为0,组分内部存在排斥作用时,不会出现调制不稳定性,组分内部存在吸引作用时,会出现调制不稳定性,并且调制不稳定性区间长度随吸引作用的增强而增加;组分之间相互作用不为0时,组分之间的相互作用以平方形式出现,其正负不会对调制不稳定性产生实质性影响.存在SOC相互作用时,SOC相互作用会引起增益谱曲线的不规则振荡,破坏原来的调制不稳定性区间. 展开更多
关键词 极化激元凝聚 调制不稳定性 自旋-轨道耦合 双分量
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Sandwich structures with tapered tubes as core:A quasi-static investigation
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作者 Xinmei Xiang Dehua Shao +5 位作者 Xin Zhang Umer Sharif Ngoc San Ha Li Xiang Jing Zhang Jiang Yi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期447-462,共16页
In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to c... In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to create the hollow centers of the tapering tubes,with and without corrugations.The results demonstrate that the energy absorption(EA)and specific energy absorption(SEA)of the single corrugated tapered tube sandwich are 51.6% and 19.8% higher,respectively,than those of the conical tube sandwich.Furthermore,the results demonstrate that energy absorbers can benefit from corrugation in order to increase their efficiency.Additionally,the tapered corrugated tubes'resistance to oblique impacts was studied.Compared to a straight tube,the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force(PCF),according to numerical simulations.After conducting a parametric study,it was discovered that the energy absorption performance of the sandwich construction is significantly affected by the amplitude,number of corrugations,and wall thickness.EA and SEA of DTS with corrugation number of 8 increased by 17.4%and 29.6%,respectively,while PCF decreased by 9.2% compared to DTS with corrugation number of 10. 展开更多
关键词 Sandwich structure Corrugated tube Tapered tube QUASI-STATIC Energy absorption
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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Nasogastric tube syndrome:A Meta-summary of case reports
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作者 Deven Juneja Prashant Nasa +1 位作者 Gunjan Chanchalani Ravi Jain 《World Journal of Clinical Cases》 SCIE 2024年第1期119-129,共11页
BACKGROUND Since its description in 1790 by Hunter,the nasogastric tube(NGT)is commonly used in any healthcare setting for alleviating gastrointestinal symptoms or enteral feeding.However,the risks associated with its... BACKGROUND Since its description in 1790 by Hunter,the nasogastric tube(NGT)is commonly used in any healthcare setting for alleviating gastrointestinal symptoms or enteral feeding.However,the risks associated with its placement are often underes-timated.Upper airway obstruction with a NGT is an uncommon but potentially life-threatening complication.NGT syndrome is characterized by the presence of an NGT,throat pain and vocal cord(VC)paralysis,usually bilateral.It is poten-tially life–threatening,and early diagnosis is the key to the prevention of fatal upper airway obstruction.However,fewer cases may have been reported than might have occurred,primarily due to the clinicians'unawareness.The lack of specific signs and symptoms and the inability to prove temporal relation with NGT insertion has made diagnosing the syndrome quite challenging.AIM To review and collate the data from the published case reports and case series to understand the possible risk factors,early warning signs and symptoms for timely detection to prevent the manifestation of the complete syndrome with life-threatening airway obstruction.METHODS We conducted a systematic search for this meta-summary from the database of PubMed,EMBASE,Reference Citation Analysis(https://www.referencecitation-analysis.com/)and Google scholar,from all the past studies till August 2023.The search terms included major MESH terms"Nasogastric tube","Intubation,Gastrointestinal","Vocal Cord Paralysis",and“Syndrome”.All the case reports and case series were evaluated,and the data were extracted for patient demographics,clinical symptomatology,diagnostic and therapeutic interventions,clinical course and outcomes.A datasheet for evaluation was further prepared.RESULTS Twenty-seven cases,from five case series and 13 case reports,of NGT syndrome were retrieved from our search.There was male predominance(17,62.96%),and age at presentation ranged from 28 to 86 years.Ten patients had diabetes mellitus(37.04%),and nine were hypertensive(33.33%).Only three(11.11%)patients were reported to be immunocompromised.The median time for developing symptoms after NGT insertion was 14.5 d(interquartile range 6.25-33.75 d).The most commonly reported reason for NGT insertion was acute stroke(10,37.01%)and the most commonly reported symptoms were stridor or wheezing 17(62.96%).In 77.78%of cases,bilateral VC were affected.The only treatment instituted in most patients(77.78%)was removing the NG tube.Most patients(62.96%)required tracheostomy for airway protection.But 8 of the 23 survivors recovered within five weeks and could be decannulated.Three patients were reported to have died.CONCLUSION NGT syndrome is an uncommon clinical complication of a very common clinical procedure.However,an under-reporting is possible because of misdiagnosis or lack of awareness among clinicians.Patients in early stages and with mild symptoms may be missed.Further,high variability in the presentation timing after NGT insertion makes diagnosis challenging.Early diagnosis and prompt removal of NGT may suffice in most patients,but a significant proportion of patients presenting with respiratory compromise may require tracheostomy for airway protection. 展开更多
关键词 Nasogastric tube Nasogastric tube syndrome Ryle’s tube Sofferman syndrome Vocal cord paralysis
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Analysis of impact pressure,rock-breaking effect,and ground vibration induced by the disposable CO_(2)fracturing tube
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作者 Chong Yu Yongan Ma +3 位作者 Haibo Li Shouchun Deng Yafei Hao Kuan Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3099-3121,共23页
The technology of expansion fracturing with liquid CO_(2)(EFLCO_(2))has attracted increasing attention due to reduced vibration and damage.The disposable fracturing tube has been developed and is gradually replacing t... The technology of expansion fracturing with liquid CO_(2)(EFLCO_(2))has attracted increasing attention due to reduced vibration and damage.The disposable fracturing tube has been developed and is gradually replacing the Cardox tube.However,there is a lack of impact pressure testing of disposable tubes under real working conditions,selection of gas explosion design parameters,and systematic analysis of blasting vibration.This limitation has constrained the widespread application of disposable fracturing tubes in engineering.A joint monitoring of the pressure-time curves in the disposable tubes and boreholes was conducted.The rock-breaking effect of varying hole spacing parameters in the EFLCO_(2)design was analyzed,and a systematic study was carried out on the vibration peak value,frequency,and energy characteristics.The results show that(1)the pressure distribution characteristics,stress peak value,and duration in the disposable tubes are different from those of Cardox tubes,which show multi-peak distribution,low-pressure peak value,and short duration.The correlation between the pressure in the disposable tube,filling pressure,and liquid CO_(2)weight is established,and a theoretical calculation method for the borehole wall pressure is proposed;(2)The hole spacing in rocks of different hardness is suggested;and(3)At the same scale distance,the peak particle velocity(PPV)caused by EFLCO_(2)(PPVCO_(2))is significantly smaller than that caused by blasting(PPVexplosive).The ratio of PPVexplosive to PPVCO_(2)is a power function related to scale distance,and a distance-related zonality exist in this relationship.The frequency composition of the vibration signal caused by EFLCO_(2)is relatively simple with a narrow frequency band.Its PPV and energy are mainly concentrated in the low-frequency band.This research contributes to the optimization of disposable fracturing tubes,gas explosion design,and vibration hazard control. 展开更多
关键词 Disposable tube Liquid CO_(2) Impact pressure Hole spacing Vibration effect Cardox tube
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Crashworthiness Design and Multi-Objective Optimization of Bionic Thin-Walled Hybrid Tube Structures
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作者 Pingfan Li Jiumei Xiao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期999-1016,共18页
Thin-walled structures are widely used in cars due to their lightweight construction and energy-absorbing properties.However,issues such as high initial stress and lowenergy-absorbing efficiency arise.This study propo... Thin-walled structures are widely used in cars due to their lightweight construction and energy-absorbing properties.However,issues such as high initial stress and lowenergy-absorbing efficiency arise.This study proposes a novel energy-absorbing structure inwhich a straight tube is combinedwith a conical tube and a bamboo-inspired bulkhead structure is introduced.This configuration allows the conical tube to flip outward first and then fold together with the straight tube.This deformation mode absorbs more energy and less peak force than the conical tube sinking and flipping inward.Through finite element numerical simulation,the specific energy absorption capacity of the structure is increased by 26%compared to that of a regular circular cross-section tube.Finally,the impact resistance of the bionic straight tapered tube structure is further improved through multi-objective optimization,promoting the engineering application and lightweight design of hybrid cross-section tubes. 展开更多
关键词 CRASHWORTHINESS tube inversion multi-objective optimization energy absorption
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Hollow tubes constructed by carbon nanotubes self-assembly for CO_(2) capture
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作者 CHEN Xu-rui WU Jun +1 位作者 GU Li CAO Xue-bo 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2256-2267,共12页
Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their mac... Carbon nanotubes(CNTs)have garnered significant attention in the fields of science,engineering,and medicine due to their numerous advantages.The initial step towards harnessing the potential of CNTs involves their macroscopic assembly.The present study employed a gentle and direct self-assembly technique,wherein controlled growth of CNT sheaths occurred on the metal wire’s surface,followed by etching of the remaining metal to obtain the hollow tubes composed of CNTs.By controlling the growth time and temperature,it is possible to alter the thickness of the CNTs sheath.After immersing in a solution containing 1 g/L of CNTs at 60℃ for 24 h,the resulting CNTs layer achieved a thickness of up to 60μm.These hollow CNTs tubes with varying inner diameters were prepared through surface reinforcement using polymers and sacrificing metal wires,thereby exhibiting exceptional attributes such as robustness,flexibility,air tightness,and high adsorption capacity that effectively capture CO_(2) from the gas mixture. 展开更多
关键词 carbon nanotubes SELF-ASSEMBLY hollow tubes CO_(2) capture
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A novel efficient energy absorber with free inversion of a metal foam-filled circular tube
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作者 Jianxun ZHANG Jinwen BAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第1期1-14,共14页
In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analyticall... In this paper, a novel efficient energy absorber with free inversion of a metal foam-filled circular tube(MFFCT) is designed, and the axial compressive behavior of the MFFCT under free inversion is studied analytically and numerically. The theoretical analysis reveals that the energy is mainly dissipated through the radial bending of the metal circular tube, the circumferential expansion of the metal circular tube, and the metal filled-foam compression. The principle of energy conservation is used to derive the theoretical formula for the minimum compressive force of the MFFCT over free inversion under axial loading. Furthermore, the free inversion deformation characteristics of the MFFCT are analyzed numerically. The theoretical steady values are found to be in good agreement with the results of the finite element(FE) analysis. The effects of the average diameter of the metal tube, the wall thickness of the metal tube, and the filled-foam strength on the free inversion deformation of the MFFCT are considered. It is observed that in the steady deformation stage, the load-carrying and energy-absorbing capacities of the MFFCT increase with the increase in the average diameter of the metal tube, the wall thickness of the metal tube, or the filled-foam strength. The specific energy absorption(SEA) of free inversion of the MFFCT is significantly higher than that of the metal tube alone. 展开更多
关键词 metal foam-filled circular tube(MFFCT) free inversion load-carrying capacity energy absorption
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Numerical simulation of the influence factors of NO_(x) emission on a W-type radiant tube
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作者 LIU Yanyan 《Baosteel Technical Research》 CAS 2024年第1期1-7,共7页
The radiant tube burner was modeled and analyzed by the numerical simulation method to investigate the influence factors and rules of NO_(x) emissions in a W-type radiant tube.These factors,which include air preheatin... The radiant tube burner was modeled and analyzed by the numerical simulation method to investigate the influence factors and rules of NO_(x) emissions in a W-type radiant tube.These factors,which include air preheating temperature,excess air coefficient,and fuel gas composition,were modified to study their effects on NO_(x) emissions under varying working conditions.Simulation results were compared with the theoretical calculation value based on chemical reaction equilibrium theory and the onsite experimental value to verify the simulation accuracy.The results show that NO_(x) emissions rise with increasing air preheating temperatures.NO_(x) production increases to an extreme value and then decreases during the oxygen-poor to oxygen-enriched process with the rise of the excess air coefficient.Enhancing the proportion of coke oven gas in the fuel gas raises the combustion temperature as well as the NO_(x) discharge.Both the thermal efficiency and NO_(x) emissions should be balanced.Therefore,the recommended values based on the simulation results are as follows:the air preheating temperature should not exceed 400℃,the excess air coefficient should be between 1.1 and 1.2,and the volume fraction of the coke oven gas should not exceed 30%. 展开更多
关键词 W-type radiant tube NO_(x) combustion numerical simulation
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A new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy improves patients’postoperative quality of life
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作者 Fenghua Zhang Lin Lin +2 位作者 Huan Zhang Jinghua Liu Rui Wang 《Laparoscopic, Endoscopic and Robotic Surgery》 2024年第3期107-112,共6页
Objective Laparoscopic surgery has become a routine general surgery with many advantages,such as alleviating abdominal pain.However,postoperative pain caused by abdominal drainage tubes has attracted little attention ... Objective Laparoscopic surgery has become a routine general surgery with many advantages,such as alleviating abdominal pain.However,postoperative pain caused by abdominal drainage tubes has attracted little attention from medical staff.The aim of this study was to explore the influence of a new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy(LC)on patients’postoperative quality of life.Methods Patients who underwent 3-port LC with abdominal drainage tubes in the Department of Hepatobiliary Surgery of Linyi People’s Hospital from March 1,2023 to October 31,2023 due to gallstones with chronic cholecystitis were selected for this study.The patients were randomly divided into an experimental group and a control group.In the experimental group,the new abdominal drainage tube fixation method was used,while in the control group,the traditional method was used.Afterward,the quality of life of patient in terms of pain,activity,recovery time,and mental health status was evaluated.The exudate around the patient’s drainage tube was collected for bacterial culture and analysis.Results A total of 139 patients were randomly divided into an experimental group(70 patients)and a control group(69 patients).The patients’baseline characteristics were not significantly different.The patients in the experimental group had better outcomes in quality of life,with higher pain scores(24.03±2.37 vs.15.48±2.29,p<0.001)and activity scores(20.57±1.78 vs.14.13±1.43,p<0.001),and a shorter postoperative recovery time(2.36±0.68 d vs.2.96±1.34 d,p<0.001).The same results were shown in linear regression analysis scores of the 2 groups.The positive rate of bacterial culture in the exudate around the patient’s drainage tube in the experimental group was significantly lower than that in the control group(12.9%vs.43.5%,p<0.001);and furthermore,the positive rate of conditional pathogenic bacteria was even lower(7.1%vs.33.3%,p<0.001)in the experimental group than in the control group.Conclusion This new abdominal drainage tube fixation method can effectively promote patient rehabilitation and improve the quality of life for patient following 3-port LC with abdominal drainage tubes. 展开更多
关键词 Abdominal drainage tube Surgical site infection Quality of life Fixation method Laparoscopic cholecystectomy
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High-grade serous carcinoma of the fallopian tube in a young woman with chromosomal 4q abnormality:A case report
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作者 Kai-Cheng Zhang Shao-Yin Chu Dah-Ching Ding 《World Journal of Clinical Cases》 SCIE 2024年第18期3539-3547,共9页
BACKGROUND Few studies have reported an association between an increased risk of acquiring cancers and survival in patients with 4q deletion syndrome.This study presents a rare association between chromosome 4q abnorm... BACKGROUND Few studies have reported an association between an increased risk of acquiring cancers and survival in patients with 4q deletion syndrome.This study presents a rare association between chromosome 4q abnormalities and fallopian tube highgrade serous carcinoma(HGSC)in a young woman.CASE SUMMARY A 35-year-old woman presented with acute dull abdominal pain and a known chromosomal abnormality involving 4q13.3 duplication and 4q23q24 deletion.Upon arrival at the emergency room,her abdomen appeared ovoid and distended with palpable shifting dullness.Ascites were identified through abdominal ultrasound,and computed tomography revealed an omentum cake and an enlarged bilateral adnexa.Blood tests showed elevated CA-125 levels.Paracentesis was conducted,and immunohistochemistry indicated that the cancer cells favored an ovarian origin,making us suspect ovarian cancer.The patient underwent debulking surgery,which led to a diagnosis of stage IIIC HGSC of the fallopian tube.Subsequently,the patient received adjuvant chemotherapy with carboplatin and paclitaxel,resulting in stable current condition.CONCLUSION This study demonstrates a rare correlation between a chromosome 4q abnormality and HGSC.UBE2D3 may affect crucial cancer-related pathways,including P53,BRCA,cyclin D,and tyrosine kinase receptors,thereby possibly contributing to cancer development.In addition,ADH1 and DDIT4 may be potential influencers of both carcinogenic and therapeutic responses. 展开更多
关键词 High-grade serous carcinoma Fallopian tube Young age Chromosomal abnormality Mental retardation AGING Case report
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Experimental and Numerical Investigation of the Performance of Turbulent Heat Transfer in Tubes with Different Cross-Sectioned Wire Coils
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作者 Ali Shokor Golam 《Frontiers in Heat and Mass Transfer》 EI 2024年第2期633-653,共21页
The thermal-hydraulic performance of plain tubes with and without wire coils in turbulent regimes is investigated experimentally and numerically.The effects of wire coil distribution(circular cross section)within the ... The thermal-hydraulic performance of plain tubes with and without wire coils in turbulent regimes is investigated experimentally and numerically.The effects of wire coil distribution(circular cross section)within the tube were explored experimentally,and water was employed as the working fluid.The numerical simulation was carried out using software programmer ANSYS Fluent 2019 R3 using the finite-volume approach.In the turbulent regime,six cross-sectionedwire coilswere analyzed,including:circular,rectangular,hexagonal,square,star shape,and triangle.The utilization of a tube with a wire coil has been shown to increase heat transfer rate and pump consumption.The results indicate a high level of concurrence,as the deviations are all below 8%.Compared with plain tube,the wire coils,according to the arrangement(TWD),gave the best PEC.The heat transfer enhancement ability of different cross sections follows the following order:StCS>RCS>HCS>SqCS>CCS>TCS.Also,the sequence of pump consumption for each cross section is as follows:RCS>StCS>SqCS>HCS>CCS>TCS. 展开更多
关键词 Wire coil performance evaluation criterion friction factor circular tube cross section
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基于可拓相平面稳定域划分的Tube-MPC车辆稳定性控制
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作者 苏东旭 赵治国 +2 位作者 赵坤 李刚 于勤 《汽车工程》 EI CSCD 北大核心 2024年第9期1654-1667,共14页
针对分布式四轮驱动电动车辆在极限工况下稳定性控制难题,考虑了横摆角速度、横纵向加速度等传感器噪声以及质心侧偏角估计误差的影响,提出了基于可拓理论的相平面稳定域划分方法以及自适应管道模型预测控制(ATMPC)算法,以快速量化车辆... 针对分布式四轮驱动电动车辆在极限工况下稳定性控制难题,考虑了横摆角速度、横纵向加速度等传感器噪声以及质心侧偏角估计误差的影响,提出了基于可拓理论的相平面稳定域划分方法以及自适应管道模型预测控制(ATMPC)算法,以快速量化车辆稳定性程度,并在满足跟踪精度的前提下保证车辆行驶的稳定性。所设计的车辆横摆稳定性控制系统采用分层设计架构,其中上层基于可拓理论,将车辆质心侧偏角-橫摆角速度相平面与可拓控制域相关联,并根据车辆实际状态判断可拓控制域并计算关联函数,实现了下层的管道模型预测控制(TubeMPC)控制目标权重与控制模式的决策;下层基于Tube-MPC对期望横摆角速度和质心侧偏角进行跟踪,实现附加横摆力矩的精准决策,之后采用轮胎负荷率优化方法进行横摆力矩的分配。通过CarSim与Simulink软件联合仿真,对所设计的控制策略进行仿真验证。结果表明,相较于常规MPC算法,所提出的控制架构与ATMPC控制策略能够有效提升车辆在极限工况下的行驶稳定性以及噪声干扰环境下的鲁棒性。 展开更多
关键词 分布式驱动车辆 稳定性控制 可拓相平面 管道模型预测控制
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A Meta-Analysis of the Effect of Modified Gastric Tube Length on Enteral Nutrition in Stroke Patients
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作者 Xuehong Tang Bo Fang Zhenzhen Cai 《Journal of Clinical and Nursing Research》 2024年第10期147-158,共12页
Objective:To systematically evaluate the effect of modified length of gastric tube implantation in stroke patients.Methods:Randomized controlled studies on the effect of narrative therapy on negative emotions of malig... Objective:To systematically evaluate the effect of modified length of gastric tube implantation in stroke patients.Methods:Randomized controlled studies on the effect of narrative therapy on negative emotions of malignant tumor patients were published in PubMed,EMbase,Web of Science,Cochrane Library,CNKY.Wanfang Data,VIP Database and CBM disc from database establishment to May 2021.RewMan 5.2 software was used for the meta-analysis.Results:Ten articles were included,involving 1140 patients in total.Results of meta-analysis showed that improved length of gastric tube implantation could reduce the incidence of aspiration pneumonia in stroke patients with enteral nutrition[OR=0.18,95%CI(0.10,0.31),P<0.00001],reduce gastroesophageal reflux rate[OR=0.13,95%CI(0.04,0.38),P<0.0002],the incidence of aspiration[OR=0.23,95%CI(0.11,0.38),P<0.00001],the incidence of abdominal distension and diarrhea[OR=0.13,95%CI(0.06,0.28),P<0.00001],the incidence of choking cough[OR=0.20,95%CI(0.07,0.61),P<0.005],but no difference between the two groups in terms of reducing gastric residual[OR=0.10,95%CI(2.40,2.60),P=0.94].Conclusions:The modified length of the gastric tube can replace the traditional length of the gastric tube in the application of stroke patients,can reduce the complications of enteral nutrition,is safe and feasible.However,due to the limitation of the quality and quantity of the included studies,we should be cautious about the results of this meta-analysis and expect to carry out more large-sample and high-quality randomized controlled trials for demonstration. 展开更多
关键词 STROKE Length of gastric tube Modified gastric tube META-ANALYSIS Systematic evaluation COMPLICATIONS
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足部位置和座椅高度对脑瘫儿童坐-站转移下肢运动学和动力学参数的影响
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作者 李文静 高晓 +3 位作者 李爱华 倪燕 孙威 王疆娜 《中国组织工程研究》 CAS 北大核心 2025年第21期4469-4476,共8页
背景:足位和座椅高度是影响“坐-站转移”的重要因素,但目前对“坐-站转移”动作的研究多侧重于健康人群和帕金森患者,痉挛型脑瘫儿童在不同座椅高度和足部位置下执行“坐-站转移”任务中的下肢运动学和动力学特征尚未可知。目的:探究... 背景:足位和座椅高度是影响“坐-站转移”的重要因素,但目前对“坐-站转移”动作的研究多侧重于健康人群和帕金森患者,痉挛型脑瘫儿童在不同座椅高度和足部位置下执行“坐-站转移”任务中的下肢运动学和动力学特征尚未可知。目的:探究不同足部位置及座椅高度对脑瘫儿童执行“坐-站转移”任务过程中下肢运动学和动力学参数的影响。方法:选择7名痉挛型脑瘫儿童作为研究对象,对其进行6个任务即3种座椅高度(高、中、低凳)×2种足位(前、后足位)的“坐-站转移”动作测试,采集脑瘫儿童在不同足位和座椅高度下“坐-站转移”时的运动学和动力学数据。结果与结论:(1)时间特征结果表明,相较于低凳条件,脑瘫儿童在高凳条件下进行“坐-站转移”任务所需总时间显著减少(P=0.046);(2)动力学结果表明,抬离瞬间,双足后位条件下的膝关节屈曲力矩显著大于双足前位条件(P=0.049);相较于中凳条件,在高凳条件下膝关节屈曲力矩显著减小(P <0.001);(3)结果提示抬高座椅高度和改变足位条件均对痉挛型脑瘫儿童的“坐-站转移”表现有影响,在高凳双足后位条件下儿童使用较小的运动补偿就可以完成坐站动作;同时高座椅可作为痉挛型脑瘫儿童增强“坐-站转移”表现的辅助工具,高凳双足后位条件更有助于脑瘫儿童“坐-站转移”动作的完成。 展开更多
关键词 痉挛型脑瘫 足位 座椅高度 -站转移 姿势控制
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基于卡尔加里-剑桥指南的沙龙培训模式提升全科规培医师医患沟通技能的对照研究
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作者 彭涛 邹川 +2 位作者 曾欣 张焱 沈静 《中国全科医学》 CAS 北大核心 2025年第1期71-76,共6页
背景医患沟通技能是全科医生的核心岗位胜任力之一,高水平的医患沟通能力是创建和谐医患关系的基石,有助于提高患者就医获得感和满意度。而我国全科医生沟通能力普遍偏低,有待探索出一种适应我国国情、满足我国全科医生沟通需求的医患... 背景医患沟通技能是全科医生的核心岗位胜任力之一,高水平的医患沟通能力是创建和谐医患关系的基石,有助于提高患者就医获得感和满意度。而我国全科医生沟通能力普遍偏低,有待探索出一种适应我国国情、满足我国全科医生沟通需求的医患沟通培训模式来提高其医患沟通能力。目的探索基于卡尔加里-剑桥指南的沙龙培训模式在全科规培医师医患沟通技能培训中的应用效果,为构建适合我国国情的医患沟通培训体系提供参考依据。方法选取成都市第五人民医院2019—2020年度全科规培医师40名作为研究对象,按照随机数字表法分为沙龙组和对照组,每组20名,其中沙龙组使用基于卡尔加里-剑桥指南的沙龙培训模式进行医患沟通培训,对照组设置为空白对照,培训前、培训后1周分别对两组学员采用标准化病人(SP)模式进行接诊,使用医患沟通评价量表(SEGUE量表)进行现场观察评分,比较两组学员的医患沟通培训效果。结果最终纳入28名,其中沙龙组15名,对照组13名,培训后沙龙组规培医师SEGUE量表评分从(11.80±4.36)分提高至(18.07±4.11)分,对照组规培医师SEGUE量表评分从(12.15±4.63)分提高至(14.46±3.71)分。沙龙组培训后的SEGUE量表评分与培训前的比较,差异有统计学意义(t=3.250,P<0.001);对照组培训后的SEGUE量表评分与培训前比较,差异无统计学意义(t=2.582,P=0.624);培训后对SEGUE量表中的25个项目进行分析,沙龙组与对照组SEGUE量表评分比较,差异有统计学意义(P<0.05)。沙龙组以下5个项目结果优于对照组,准备阶段中的“建立个人信任关系”(93.3%比7.7%)、“保护患者的隐私/尊重患者选择权”(53.3%比15.4%);理解患者阶段中的“认同患者为疾病所付出的努力、改变及其遇到的困难”(33.3%比23.1%)、“表达关心,使患者感到温暖/树立信心”(100.0%比69.2%);结束问诊阶段中的“询问患者是否还有其他的问题需要探讨”(66.7%比23.1%)。结论基于卡尔加里-剑桥指南的沙龙培训模式对全科规培医师进行医患沟通技能培训可增强学员主动参加培训的兴趣和积极性,对于医患沟通能力的提升具有较好的培训效果,值得借鉴和推广。 展开更多
关键词 全科医学 全科医师 规范化培训 医患沟通 沟通培训 卡尔加里-剑桥指南
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运动疗法通过机械-化学偶联治疗慢性非特异性下背痛
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作者 张佳乐 王富森 +4 位作者 邱镇锐 樊鑫铭 邹吉龙 毕郑刚 孙佳冰 《中国组织工程研究》 CAS 北大核心 2025年第11期2377-2384,共8页
背景:目前运动疗法是非药物治疗腰痛的有效方法,运动疗法可通过骨骼和肌肉之间的机械-化学偶联维持腰椎的稳定,但目前尚无关于运动疗法通过机械-化学偶联缓解慢性非特异性下背痛之间研究进展及最佳治疗方案的明确阐述。目的:综述运动疗... 背景:目前运动疗法是非药物治疗腰痛的有效方法,运动疗法可通过骨骼和肌肉之间的机械-化学偶联维持腰椎的稳定,但目前尚无关于运动疗法通过机械-化学偶联缓解慢性非特异性下背痛之间研究进展及最佳治疗方案的明确阐述。目的:综述运动疗法时椎旁肌通过机械-化学偶联影响腰椎稳定性进而缓解慢性非特异性下背痛的相关研究进展,以及目前运动疗法治疗慢性非特异性下背痛的最佳方案。方法:在万方数据库、中国知网、维普、Web of Science和PubMed数据库进行文献检索,以“慢性非特异性下背痛,腰椎稳定,椎旁肌,运动疗法”为中文检索词,以“chronic nonspecific low back pain,lumbar stabilization,paravertebral muscle,exercise therapy”为英文检索词,检索各数据库建库至2024年1月发表的相关文献,最终纳入93篇文献进行归纳总结。结果与结论:运动疗法可以通过适当的机械刺激作用于椎旁肌和骨骼并使其产生相应的变化。运动疗法主要通过机械-化学偶联方式来提高椎旁肌的质量,进而维持腰椎稳定,从而更好地缓解慢性非特异性下背痛,是慢性非特异性下背痛的重要干预措施。但是,对于运动疗法通过腰椎稳定来治疗慢性非特异性下背痛的确切有效方案尚无明确报道。个体化运动方案的制定对于慢性非特异性下背痛的治疗和预后尤为重要。同一个体的肌肉质量与骨骼质量是密切相关的,影像学评估椎旁肌的质量和体积对于疾病的发现和干预具有重要意义。 展开更多
关键词 机械-化学偶联 运动疗法 慢性非特异性下背痛 腰椎稳定 椎旁肌
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强震区隧道洞口段新型墙-板抗减震措施的效果分析
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作者 韩健松 崔光耀 王道远 《太原学院学报(自然科学版)》 2025年第1期9-16,共8页
为了进一步提高强震区铁路隧道的安全以及抗震性能,依托包银铁路甘德尔山隧道,运用数值模拟软件FLAC 3D,针对强震区隧道洞口段墙-板和墙-板-减震层的抗减震作用效果进行研究。研究结果表明,与不采用抗减震措施相比较,采取墙-板抗震措施... 为了进一步提高强震区铁路隧道的安全以及抗震性能,依托包银铁路甘德尔山隧道,运用数值模拟软件FLAC 3D,针对强震区隧道洞口段墙-板和墙-板-减震层的抗减震作用效果进行研究。研究结果表明,与不采用抗减震措施相比较,采取墙-板抗震措施后,横向位移减小了5.95%,竖向位移减小了45.87%,最小安全系数增大了40.91%~49.25%,最大主应力的抗震作用效果达到了63.56%,最小主应力的抗震作用效果为4.04%,最大剪应力抗震作用效果为8.35%;采取墙-板-减震层减震措施后,横向位移减小了13.11%,竖向位移减小了43.88%,最小安全系数增大了65.82%~74.50%,最大主应力的减震作用效果达到了75.11%,最小主应力的减震作用效果为10.21%,最大剪应力减震作用效果为12.80%。采用墙-板-减震层的抗减震措施优于墙-板结构。推荐采用墙-板-减震层措施对甘德尔山隧道进行抗减震加固设计。 展开更多
关键词 隧道工程 强震区 洞口段 --减震层 抗减震措施
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