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改进型超声引导下针状可视肾镜(Needle perc)钬激光碎石术治疗肾下盏结石的临床评价:与输尿管软镜对比
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作者 吴辉 孔莹莹 +3 位作者 高江涛 陈松林 杨银毫 李纪华 《现代泌尿外科杂志》 CAS 2024年第4期302-305,共4页
目的比较改进型超声引导下针状可视肾镜(Needle perc)钬激光碎石术和输尿管软镜下钬激光碎石术治疗1~2 cm肾下盏结石的效果,为临床治疗方式的选择提供参考。方法回顾性分析2022年1月—2023年5月郑州市第一人民医院收治的60例肾内单发下... 目的比较改进型超声引导下针状可视肾镜(Needle perc)钬激光碎石术和输尿管软镜下钬激光碎石术治疗1~2 cm肾下盏结石的效果,为临床治疗方式的选择提供参考。方法回顾性分析2022年1月—2023年5月郑州市第一人民医院收治的60例肾内单发下盏结石(最大径1~2 cm)患者的临床资料,比较行输尿管软镜钬激光碎石术的30例患者(软镜组)和改进型超声引导下Needle perc钬激光碎石术的30例患者(Needle perc组)的临床资料。结果Needle perc组较软镜组的整体住院时间[(3.00±1.25)d vs.(4.00±1.25)d]、手术时间[(44.63±5.42)min vs.(48.50±7.24)min]和住院花费[(15518±441)元vs.(16872±903)元]均较少(P<0.05)。Needle perc组术后清石率高于软镜组[93.3%(28/30)vs.50.7%(15/30),P<0.001]。术后降钙素原(PCT)上升幅度低于软镜组[(0.02±0.01)vs.(0.12±0.18),P=0.007],而并发症发生率低于软镜组[3.3%(1/30)vs.26.7%(8/30),P=0.030]。结论对于1~2 cm的肾下盏单发结石,改进型超声引导下Needle perc钬激光碎石术清石率较高、并发症发生率低,安全且有效。 展开更多
关键词 肾结石 针状可视肾镜 钬激光碎石术 输尿管软镜 结石清除率
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Meta-analysis of Clinical Efficacy of Warm Needling Acupuncture in the Treatment of Lumbar Disc Herniation
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作者 Duola Balama +1 位作者 Hairihan Shuangmei 《Medicinal Plant》 CAS 2023年第1期76-79,共4页
[Objectives]To evaluate the efficacy of warm needling acupuncture in the treatment of lumbar disc herniation(LDH)by Meta-analysis.[Methods]Randomized controlled trial of warm needling acupuncture in the treatment of l... [Objectives]To evaluate the efficacy of warm needling acupuncture in the treatment of lumbar disc herniation(LDH)by Meta-analysis.[Methods]Randomized controlled trial of warm needling acupuncture in the treatment of lumbar disc herniation published from January 2000 to December 2021 was searched by Cochrane Library,PubMed,VIP,CNKI and Wanfang.After the quality evaluation of the literature,the Meta-analysis of the literature was carried out by using Review Manager 5.3.[Results]A total of 10 studies were included,involving a total of 980 patients.The results of Meta-analysis showed that warm needling acupuncture in the treatment of lumbar disc herniation could improve the total clinical effective rate,OR=5.38,95%CI(3.40,8.49),P<0.00001;decrease the VAS score,MD=-3.33,95%CI[-4.53,-2.12],z=5.42(P<0.00001);increase the JOA score,MD=-5.63,95%CI[-8.12,-3.14];improve the dysfunction,MD=-5.63,95%CI[-8.12,-3.14],z=4.43(P<0.00001);decrease inflammatory factors,MD=-11.09,95%CI[-13.60,-8.58],z=8.65(P<0.00001).And the recurrence rate was low,OR=0.33,95%CI[0.15,0.70],z=2.86(P=0.004).[Conclusions]Warm needling acupuncture could effectively treat lumbar disc herniation and relieve pain symptoms.However,due to the general poorness of literature quality and the low quality of evidence,high-quality randomized controlled trials are still needed. 展开更多
关键词 Warm needling acupuncture Lumbar disc herniation(LDH) META-ANALYSIS
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Clinical Observation of Warm Needling Acupuncture of Mongolian Medicine in the Treatment of Lumbar Disc Herniation
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作者 Hairihan Balama +1 位作者 Sarula WANG Shuangmei 《Medicinal Plant》 CAS 2023年第1期84-86,89,共4页
[Objectives]To observe the clinical efficacy of warm needling acupuncture of Mongolian medicine in the treatment of lumbar disc herniation(LDH).[Methods]120 patients with lumbar disc herniation hospitalized in Inner M... [Objectives]To observe the clinical efficacy of warm needling acupuncture of Mongolian medicine in the treatment of lumbar disc herniation(LDH).[Methods]120 patients with lumbar disc herniation hospitalized in Inner Mongolia International Mongolian Hospital from June 2019 to June 2022 were randomly divided into observation group(n=60)and control group(n=60).The observation group was treated with warm needling acupuncture of Mongolian medicine,and the control group was treated with common acupuncture of Mongolian medicine,with two weeks as a course of treatment.The pain visual analogue scale(VAS)and Japanese orthopaedic association(JOA)score were observed before and after treatment,and the clinical efficacy was evaluated by the changes of clinical symptoms and signs of Mongolian medicine.[Results]The cure rate of the observation group was 71.7%,which was better than that of the control group(53.3%).The difference in the cure rate between the two groups was statistically significant,X 2=4.302,P=0.038.The total markedly effective rate(cured+markedly effective)of the observation group was 90.0%,while that of the control group was 83.3%.There was no significant difference in the total markedly effective rate between the two groups,X 2=1.154,P=0.283.The total effective rate(cured+markedly effective+effective)of the observation group was 100%,while that of the control group was 95.0%.There was no significant difference in the total effective rate between the two groups,and the continuous corrected chi-square value was 1.368 and 0.242.After treatment,the degree of low back pain,lower limb pain and dyskinesia were significantly improved in the two groups,the observation group was better than the control group,and the difference was statistically significant(P<0.05).[Conclusions]The warm needling acupuncture of Mongolian medicine was effective in the treatment of lumbar disc herniation,which is worth popularizing. 展开更多
关键词 Warm needling acupuncture of Mongolian medicine Lumbar disc herniation(LDH) Clinical observation
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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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History and Development of Zhuang Medicine Shallow Needling from Bone Needle,Pottery Needle,and Bronze Needle to Electroacupuncture
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作者 Yun Zhang Yuying Lan 《Proceedings of Anticancer Research》 2023年第2期28-32,共5页
Zhuang medicine shallow needling has a long history and plays a significant role in Chinese medicine.With the development of medical treatment in China,there is a constant improvement in the use of needles.Bone needle... Zhuang medicine shallow needling has a long history and plays a significant role in Chinese medicine.With the development of medical treatment in China,there is a constant improvement in the use of needles.Bone needles have been modified to pottery needles,bronze needles,and electroacupuncture.From this long development history,there are some improvements in terms of material and technology.By analyzing and comparing the primitive and current acupuncture instruments used in China and their therapeutic effects,it can be seen that China’s medical treatment is constantly improving and will continue to improve with technology. 展开更多
关键词 Shallow needling of Zhuang medicine Bone needle Bronze needle
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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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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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Assessment of Knowledge, Attitude and Practices among Healthcare Workers in a Tertiary Care Hospital on Needle Stick Injury
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作者 Komal Kanani Sangita Rajdev Summaiya Mullan 《Advances in Infectious Diseases》 CAS 2024年第2期487-495,共9页
Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers s... Purpose: Needle-stick injury (NSI) is one of the most potential occupational hazards for healthcare workers because of the transmission of blood-borne pathogens. As per recent data, around 30 lakh healthcare workers sustain Needle stick injuries each year. This study was conducted to assess healthcare workers’ knowledge, attitude and practices regarding needle stick injury. Materials & Methods: A cross-sectional study was conducted in a Tertiary Care Hospital over the period of 3 months. The study population consisted of Intern Doctors, Post Graduate resident Doctors, Staff Nurses, laboratory technicians of Government Medical College and New Civil Hospital, Surat (n = 300). The data were collected using a self-administered questionnaire via the means of Google Forms. Questionnaire was made with prior review literature. The data obtained were entered and analysed in Microsoft Excel. Results: The prevalence of NSI in our study was 46%, with a higher prevalence among the PG residents (72%). Overall scores regarding knowledge and attitude were better in PG residents (knowledge score > 7 in 71% and Attitude Score > 7 in 68% of PG Residents). Even though the PG residents scored highest in the knowledge category, the majority of them suffered needle stick injuries as a result of poor practice scores. Among those who had NSI (n = 139/300), 70% of study participants had superficial injuries, only 9% reported the incident, 18% got medical attention within 2 hours of the incident, and 7% followed up to recheck their viral markers status. Most incidents of NSI were due to hypodermic needles while recapping needles. Conclusion: Exposure to needle stick injuries and their underreporting remains a common problem. It is imperative that healthcare workers receive regular training on the proper handling of sharp objects. We can also draw the conclusion that preventing NSIs requires putting knowledge into practice. 展开更多
关键词 needle Stick Injury KNOWLEDGE ATTITUDE Practice Healthcare Workers
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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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MXene Enhanced 3D Needled Waste Denim Felt for High‑Performance Flexible Supercapacitors
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作者 Wei Fan Qi Wang +8 位作者 Kai Rong Yang Shi Wanxi Peng Handong Li Zhanhu Guo Ben Bin Xu Hua Hou Hassan Algadi Shengbo Ge 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期383-394,共12页
MXene,a transition metal carbide/nitride,has been prominent as an ideal electrochemical active material for supercapacitors.However,the low MXene load limits its practical applications.As environmental concerns and su... MXene,a transition metal carbide/nitride,has been prominent as an ideal electrochemical active material for supercapacitors.However,the low MXene load limits its practical applications.As environmental concerns and sustainable development become more widely recognized,it is necessary to explore a greener and cleaner technology to recycle textile by-products such as cotton.The present study proposes an effective 3D fabrication method that uses MXene to fabricate waste denim felt into ultralight and flexible supercapacitors through needling and carbonization.The 3D structure provided more sites for loading MXene onto Z-directional fiber bundles,resulting in more efficient ion exchange between the electrolyte and electrodes.Furthermore,the carbonization process removed the specific adverse groups in MXenes,further improving the specific capacitance,energy density,power density and electrical conductivity of supercapacitors.The electrodes achieve a maximum specific capacitance of 1748.5 mF cm-2 and demonstrate remarkable cycling stability maintaining more than 94%after 15,000 galvanostatic charge/discharge cycles.Besides,the obtained supercapacitors present a maximum specific capacitance of 577.5 mF cm^(-2),energy density of 80.2μWh cm^(-2)and power density of 3 mW cm^(-2),respectively.The resulting supercapacitors can be used to develop smart wearable power devices such as smartwatches,laying the foundation for a novel strategy of utilizing waste cotton in a high-quality manner. 展开更多
关键词 MXene 3D needled waste denim felt SUPERCAPACITORS CARBONIZATION
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Is magnesium deficiency the major cause of needle chlorosis of Pinus taeda in Brazil?
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作者 Antônio Carlos Vargas Motta Shizuo Maeda +6 位作者 Valdécio dos Santos dos Santos Rodrigues Tamires Maiara Ercole Stephen Arthur Prior Ana Elisa Lyra Brumat Amanda Pacheco Cardoso Moura Julierme Zimmer Barbosa João Bosco Vasconcellos Gomes 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期209-221,共13页
Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grow... Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on P.taeda were analyzed for various elements and properties.All soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple elements.YNC symptoms started at needle tips,then extended toward the needle base with time.First flush needles had longer portions with YNC than second flush needles did.Needles from the lower crown also had more symptoms along their length than those higher in the canopy.Symptoms were similar to those reported for Mg.In chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of P.taeda in various parent soils in Brazil. 展开更多
关键词 Nutritional deficiency Forest management Soil depletion Pine foliar analysis needle chlorosis
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Heat Transfer Enhancement of the Absorber Tube in a Parabolic Trough Solar Collector through the Insertion of Novel Cylindrical Turbulators
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作者 Yasser Jebbar Fadhil Fluiful Wisam Khudhayer 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1279-1297,共19页
This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical turbulators.The PTC is designed with dimensions of 2.00 m in length and 1... This study includes an experimental and numerical analysis of the performances of a parabolic trough collector(PTC)with and without cylindrical turbulators.The PTC is designed with dimensions of 2.00 m in length and 1.00 m in width.The related reflector is made of lined sheets of aluminum,and the tubes are made of stainless steel used for the absorption of heat.They have an outer diameter of 0.051 m and a wall thickness of 0.002 m.Water,used as a heat transfer fluid(HTF),flows through the absorber tube at a mass flow rate of 0.7 kg/s.The dimensions of cylindrical turbulators are 0.04 m in length and 0.047 m in diameter.Simulations are performed using the ANSYS Fluent 2020 R2 software.The PTC performance is evaluated by comparing the experimental and numerical outcomes,namely,the outlet temperature,useful heat,and thermal efficiency for a modified tube(MT)(tube with novel cylindrical turbulators)and a plain tube(PT)(tube without novel cylindrical turbulators).According to the results,the experimental outlet temperatures recorded 63.2°C and 50.5°C for the MT and PT,respectively.The heat gain reaches 1137.5 Win the MT and 685.8 Win the PT.Compared to the PT collector,the PTC exhibited a(1.64 times)higher efficiency. 展开更多
关键词 Parabolic trough collector turbulators absorber tube ANSYS thermal efficiency
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Study on the low mechanical anisotropy of extruded Mg-Zn-Mn-Ce-Ca alloy tube in the compression process
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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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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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Modified intratympanic steroid therapy for sudden sensorineural hearing loss via tympanic tube and gelfoam as a salvage treatment
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作者 Sichao Liang Yunshuo Li +6 位作者 Zhenping Guo Manlin Lu Xin Li Jia Xu Wenjing Chen Juanjuan Gao Haijin Yi 《Journal of Otology》 CAS CSCD 2024年第1期19-23,共5页
Background: Sudden sensorineural hearing loss(SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy(IST) can serve as a salvage treatm... Background: Sudden sensorineural hearing loss(SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy(IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy(SST).Objective: This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors.Methods: Totally, 74 patients who were aged 22–81 years with SSNHL were enrolled and allocated to either the control group(n = 25) or the treatment group(n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2–6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST.Results: Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies(250-8000 Hz) compared with the control group(P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment(P = 0.002), whereas age, duration of SST, and time of IST were not(P > 0.05).Conclusion: The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL. 展开更多
关键词 Modified intratympanic steroid therapy Sudden sensorineural hearing loss GELFOAM Tympanic tube
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Analysis and Optimization of the Electrohydraulic Forming Process of Sinusoidal Corrugation Tubes
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作者 Da Cai Yinlong Song +2 位作者 Hao Jiang Guangyao Li Junjia Cui 《Fluid Dynamics & Materials Processing》 EI 2024年第4期873-887,共15页
Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and crashworthiness.They can be produced at room temperature by the electrohydraulic for... Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and crashworthiness.They can be produced at room temperature by the electrohydraulic forming process.In the present study,the influence of the related parameters on the forming quality of a 6063 aluminum alloy sinusoidal corrugation tube has been assessed.In particular,the orthogonal experimental design(OED)and central composite design(CCD)methods have been used.Through the range analysis and variance analysis of the experimental data,the influence degree of wire diameter(WD)and discharge energy(DE)on the forming quality was determined.Multiple regression analysis was performed using the response surface methodology.A prediction model for the attaching-die state coefficient was established accordingly.The following optimal arrangement of parameters was obtained(WD=0.759 mm,DE=2.926 kJ).The attaching-die state coefficient reached the peak value of 0.001.Better optimized wire diameter and discharge energy for a better attaching-die state could be screened by CCD compared with OED.The response surface method in CCD was more suitable for the design and optimization of the considered process parameters. 展开更多
关键词 Electrohydraulic forming aluminum alloy tube process parameters attaching-die state 1 Introduction
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Time-resolved characteristics of a nanosecond pulsed multi-hollow needle plate packed bed dielectric barrier discharge
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作者 秦亮 李瑶 +6 位作者 郭浩 姜楠 宋颖 贾锐 周雄峰 袁皓 杨德正 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第7期48-57,共10页
In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and ac... In this paper,self-designed multi-hollow needle electrodes are used as a high-voltage electrode in a packed bed dielectric barrier discharge reactor to facilitate fast gas flow through the active discharge area and achieve large-volume stable discharge.The dynamic characteristics of the plasma,the generated active species,and the energy transfer mechanisms in both positive discharge(PD)and negative discharge(ND)are investigated by using fast-exposure intensified charge coupled device(ICCD)images and time-resolved optical emission spectra.The experimental results show that the discharge intensity,number of discharge channels,and discharge volume are obviously enhanced when the multi-needle electrode is replaced by a multihollow needle electrode.During a single voltage pulse period,PD mainly develops in a streamer mode,which results in a stronger discharge current,luminous intensity,and E/N compared with the diffuse mode observed in ND.In PD,as the gap between dielectric beads changes from 0 to250μm,the discharge between the dielectric bead gap changes from a partial discharge to a standing filamentary micro-discharge,which allows the plasma to leave the local area and is conducive to the propagation of surface streamers.In ND,the discharge only appears as a diffusionlike mode between the gap of dielectric beads,regardless of whether there is a discharge gap.Moreover,the generation of excited states N_(2)^(+)(B^(2)∑_(u)^(+))and N2(C^(3)Π_(u))is mainly observed in PD,which is attributed to the higher E/N in PD than that in ND.However,the generation of the OH(A^(2)∑^(+))radical in ND is higher than in PD.It is not directly dominated by E/N,but mainly by the resonant energy transfer process between metastable N_(2)(A^(3)∑_(u)^(+))and OH(X^(2)Π).Furthermore,both PD and ND demonstrate obvious energy relaxation processes of electron-to-vibration and vibration-to-vibration,and no vibration-to-rotation energy relaxation process is observed. 展开更多
关键词 packed bed reactor multi-hollow needle electrodes positive and negative discharges optical emission spectra time-resolved images
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Calmoseptine Ointment Tube皮肤保护剂联合院内制剂妇洁康对失禁性皮炎大鼠的作用及经济效益分析
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作者 陈碧贤 赵梓佳 +1 位作者 林燕群 赵丹 《医学理论与实践》 2024年第15期2521-2524,2532,共5页
目的:研究和探讨Calmoseptine Ointment Tube皮肤保护剂联合院内制剂妇洁康对失禁性皮炎大鼠模型的作用,并分析其经济效益,以期选出价格较实惠且效果较好的失禁性皮炎的防治方案。方法:建立失禁性皮炎大鼠模型,成功后将32只大鼠分为四组... 目的:研究和探讨Calmoseptine Ointment Tube皮肤保护剂联合院内制剂妇洁康对失禁性皮炎大鼠模型的作用,并分析其经济效益,以期选出价格较实惠且效果较好的失禁性皮炎的防治方案。方法:建立失禁性皮炎大鼠模型,成功后将32只大鼠分为四组,即妇洁康洗剂组(A组)、3M液体敷料联合造口护肤粉组(B组)、Calmoseptine Ointment Tube皮肤保护剂组(C组)、妇洁康联合Calmoseptine Ointment Tube皮肤保护剂组(D组),每组8只。根据皮肤的症状评估大鼠的失禁性皮炎严重程度,通过追踪皮炎边缘测量皮炎面积,同时进行组织病理学评估其组织损伤,免疫生化分析其嗜中性粒细胞、巨噬细胞、淋巴细胞以及血管内皮生长因子、增殖细胞核抗原等水平。并结合成本效果分析方法分析其经济效益。结果:治疗后,A、B、C三组大鼠的失禁性皮炎的严重程度、面积和恢复时间比较无显著差异(P>0.05);与D组相比,A、B、C三组大鼠失禁性皮炎的严重程度显著更高,面积更大,恢复时间更长(P<0.05)。组织病理学分析显示,A、B、C三组大鼠表皮萎缩、毛囊萎缩、胶原蛋白流失、水肿等各组织情况评分比较无显著差异(P>0.05),但与D组相比,A、B、C三组大鼠的各组织指标评分显著更高(P<0.05)。免疫生化分析显示,A、B、C、D四组大鼠的PCNA水平比较无显著差异(P>0.05);A、B、C三组大鼠的嗜中性粒细胞、巨噬细胞、淋巴细胞、VEGF水平比较无显著差异(P>0.05);与D组相比,A、B、C三组大鼠的嗜中性粒细胞、巨噬细胞、淋巴细胞、VEGF水平显著更高(P<0.05)。根据不同经济效益分析可知,CEA分析显示,D组>C组>B组>A组;CMA分析显示,D组>C组>B组>A组;C/E分析显示,D组>C组>A组>B组。ΔC/ΔE分析显示,成本额最高为D组,与其他三组进行比较,D组与A组ΔC/ΔE为7.94;D组与B组ΔC/ΔE为11.89;D组与C组ΔC/ΔE为7.57。可见在经济成本上,D组明显要高于其他三组,但从增益量上看,D组虽然治疗成本较高,但所产生的效果也较高,而且,增加的治疗成本可以带来更加满意的增量效果。结论:Calmoseptine Ointment Tube皮肤保护剂联合院内制剂妇洁康对失禁性皮炎具有较好的治疗效果,能够缩小皮炎面积,缩短恢复时间,并改善皮肤组织情况,提高免疫力。同时该治疗方案虽然治疗成本较高,但治疗效果也更好,更具经济性,能够节省治疗的整体费用,值得临床推广应用。 展开更多
关键词 Calmoseptine Ointment tube 皮肤保护剂 妇洁康 失禁性皮炎 经济效益
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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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Percutaneous ultrasound-guided coaxial core needle biopsy for the diagnosis of multiple splenic lesions: A case report
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作者 Sha-Hong Pu Wu-Yong-Ga Bao +2 位作者 Zhen-Peng Jiang Rui Yang Qiang Lu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期616-621,共6页
BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic dilemma.Consequently,a definitive diagnosis primarily relies on his-tological results.The ultrasound(US)-guide... BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic dilemma.Consequently,a definitive diagnosis primarily relies on his-tological results.The ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related complications.CASE SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic lesions.Gray-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic ma-sses.Abdominal contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-shaped,peripherally enhancing,hypodense lesions.Positron emission CT revealed numerous abnormal hyperglycemia foci.These imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring exclusion.To obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried out.The patient did not express any discomfort during the procedure.CONCLUSION Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue. 展开更多
关键词 SPLEEN Splenic disease Ultrasound BIOPSY Ultrasound-guided coaxial core needle biopsy Case report
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