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Assessing the performance of mobile AI assistants in delivering medical advice for early knee osteoarthritis
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作者 Abasi Maimaitiabula Wan-Bo Zhu +3 位作者 mo chen Xian-Yue Shen Xian-Zuo Zhang chen Zhu 《Medical Data Mining》 2025年第3期33-39,共7页
Background:This study evaluates the ability of mobile AI voice assistants(AI-VAs)to provide accurate medical advice for early knee osteoarthritis(KOA)and compares their performance with conventional web searches and h... Background:This study evaluates the ability of mobile AI voice assistants(AI-VAs)to provide accurate medical advice for early knee osteoarthritis(KOA)and compares their performance with conventional web searches and human clinicians.Methods:From September to October 2024,two AI-VAs(Apple’s Siri and Huawei’s Xiaoyi)were tested on 15 KOA-related questions in Chinese and English.The assessment focused on the accuracy of voice recognition,response capabilities,and medical advice.Siri was further tested in four international regions(USA,UK,Germany,Hong Kong)using localized languages.Results:In Chinese-language tests,Siri and Xiaoyi showed comparable voice recognition(recognition accuracy:95.6%vs.93.3%)and response ability(speech response:88.9%vs.85.7%).However,Siri provided significantly more accurate medical advice(medical advice:95.6%vs.53.3%;Z=2.762,P<0.001).External validation via Global Quality Score further confirmed Siri’s superiority(mean Global Quality Score=4.0 vs.Xiaoai=0.9).Siri outperformed Xiaoyi in English-language tests(53.3%vs.0%).While Siri’s medical advice accuracy(95.6%)surpassed non-specialist clinicians(Z=2.685,P=0.007),it primarily reflects filtered search results(Baidu/Google)rather than clinical synthesis.Claims of equivalence to junior surgeons(98.2%)must be interpreted cautiously,as AI-VAs lack diagnostic reasoning capabilities.This distinction is critical to avoid overstating their role in clinical decision-making.Conclusion:Current AI-VAs offer limited value in providing precise medical advice for KOA,primarily serving as intermediaries for web search results.Their performance varies across languages,regions,and search engines. 展开更多
关键词 mobile devices voice assistant SIRI Xiaoyi knee osteoarthritis
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Simulation on atmospheric pressure barrier discharge with varying relative position between two wavy dielectric surfaces
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作者 Xue-chen Li Wen-Jie Wan +8 位作者 Xiao-Qian Liu mo chen Kai-Yue Wu Jun-Xia Ran Xue-Xia Pang Xue-Xue Zhang Jia-Cun Wu Peng-Ying Jia Hui Sun 《Chinese Physics B》 2025年第3期474-481,共8页
As a popular approach to producing atmospheric pressure non-thermal plasma,dielectric barrier discharge(DBD)has been extensively used in various application fields.In this paper,DBD with wavy dielectric layers is nume... As a popular approach to producing atmospheric pressure non-thermal plasma,dielectric barrier discharge(DBD)has been extensively used in various application fields.In this paper,DBD with wavy dielectric layers is numerically simulated in atmospheric pressure helium mixed with trace nitrogen based on a fluid model.With varying relative position(phase difference(Δφ))of the wavy surfaces,there is a positive discharge and a negative discharge per voltage cycle,each of which consists of a pulse stage and a hump stage.For the pulse stage,maximal current increases with increasingΔφ.Results show that DBD with the wavy surfaces appears as discrete micro-discharges(MDs),which are self-organized to different patterns with varyingΔφ.The MDs are vertical and uniformly-spaced withΔφ=0,which are self-organized in pairs withΔφ=π/4.These MD pairs are merged into some bright wide MDs withΔφ=π/2.In addition,narrow MDs appear between tilted wide MDs withΔφ=3π/4.WithΔφ=π,the pattern is composed of wide and narrow MDs,which are vertical and appear alternately.To elucidate the formation mechanism of the patterns with differentΔφ,temporal evolutions of electron density and electric field are investigated for the positive discharge.Moreover,surface charge on the wavy dielectric layers has also been compared with differentΔφ. 展开更多
关键词 dielectric barrier discharge wavy dielectric surface MICRO-DISCHARGE fluid model
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SWIR FluorescenceImaging In Vivo Monitoring and Evaluating Implanted M2 Macrophages in Skeletal Muscle Regeneration
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作者 mo chen Yuzhou chen +9 位作者 Sijia Feng Shixian Dong Luyi Sun Huizhu Li Fuchun chen Nguyen Thi Kim Thanh Yunxia Li Shiyi chen You Wang Jun chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期283-294,共12页
Skeletal muscle has a robust regeneration ability that is impaired by severe injury,disease,and aging.resulting in a decline in skeletal muscle function.Therefore,improving skeletal muscle regeneration is a key challe... Skeletal muscle has a robust regeneration ability that is impaired by severe injury,disease,and aging.resulting in a decline in skeletal muscle function.Therefore,improving skeletal muscle regeneration is a key challenge in treating skeletal muscle-related disorders.Owing to their significant role in tissue regeneration,implantation of M2 macrophages(M2MФ)has great potential for improving skeletal muscle regeneration.Here,we present a short-wave infrared(SWIR)fluorescence imaging technique to obtain more in vivo information for an in-depth evaluation of the skeletal muscle regeneration effect after M2MФtransplantation.SWIR fluorescence imaging was employed to track implanted M2MФin the injured skeletal muscle of mouse models.It is found that the implanted M2MФaccumulated at the injury site for two weeks.Then,SWIR fluorescence imaging of blood vessels showed that M2MФimplantation could improve the relative perfusion ratio on day 5(1.09±0.09 vs 0.85±0.05;p=0.01)and day 9(1.38±0.16 vs 0.95±0.03;p=0.01)post-injury,as well as augment the degree of skeletal muscle regencration on day 13 post-injury.Finally,multiple linear regression analyses determined that post-injury time and relative perfusion ratio could be used as predictive indicators to evaluate skeletal muscle regeneration.These results provide more in vivo details about M2MФin skeletal muscle regeneration and confirm that M2MФcould promote angiogenesis and improve the degree of skeletal muscle repair,which will guide the research and development of M2MФimplantation to improve skeletal muscle regeneration. 展开更多
关键词 In vivo Short-wave infrared Skeletal muscle MACROPHAGE REGENERATION
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超低介电常数LiB_(x)Al_(1-x)Si_(2)O_(6)微波介质陶瓷的低温烧结
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作者 熊思宇 莫尘 +5 位作者 朱肖伟 朱国斌 陈德钦 刘来君 施晓东 李纯纯 《无机材料学报》 北大核心 2025年第5期536-544,共9页
超低介电常数锂基硅酸盐微波介质陶瓷材料作为介质基板在第五代无线通信技术中显示出极大的潜力。然而,较高的烧结温度带来的残余应力会导致材料的介电损耗增加,微波介电性能变差。本工作通过在LiAlSi_(2)O_(6)陶瓷中引入B^(3+)来减少Al... 超低介电常数锂基硅酸盐微波介质陶瓷材料作为介质基板在第五代无线通信技术中显示出极大的潜力。然而,较高的烧结温度带来的残余应力会导致材料的介电损耗增加,微波介电性能变差。本工作通过在LiAlSi_(2)O_(6)陶瓷中引入B^(3+)来减少Al^(3+)含量,从而改善LiAlSi_(2)O_(6)陶瓷的烧结温度和微波介电性能。采用固相反应法与冷等静压技术相结合的方式制备了LiB_(x)Al_(1-x)Si_(2)O_(6)(0≤x≤0.20)微波介质陶瓷,并研究了B^(3+)掺杂对该材料的烧结特性、相结构、微观形貌以及微波介电性能的影响。研究结果表明,随着掺杂量的增加,陶瓷的烧结温度由1400℃大幅降低至1000℃。同时,相对介电常数(εr)从3.95降低至3.69,品质因数(Q×f)从24300 GHz显著提升至30560 GHz,谐振频率温度系数(τf)从–45.9×10^(–6)℃^(–1)升高至–20.9×10^(–6)℃^(–1)。具体而言,εr的变化主要受材料本征极化率、晶格振动以及共价键强度的共同影响;Q×f提升则与填充分数(PF)增加和阻尼系数减小密切相关;τ_(f)增大与氧的键价(VO)存在较强的关联性。此外,x=0.20组分展现出最佳的微波介电性能,具体表现为ε_(r)=3.69,Q×f=30560 GHz,τ_(f)=–20.9×10^(–6)℃^(–1)。本研究制备的LiB_(x)Al_(1)–_(x)Si_(2)O_(6)为未来高性能微波介质陶瓷材料的开发与应用提供了重要的理论依据和实践指导。 展开更多
关键词 超低介电常数 硅酸铝锂 微波介电性能
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老年慢性胃炎患者Hp感染与血清NF-κB、G-17、IGF-1的关系研究
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作者 郭建堂 刘明贺 +3 位作者 莫晨 张永青 赵晶 许莉 《疑难病杂志》 2025年第10期1200-1204,共5页
目的探究老年慢性胃炎(CG)患者幽门螺杆菌(Hp)感染与血清核因子-κB(NF-κB)、胃泌素17(G-17)、胰岛素样生长因子-1(IGF-1)的关系。方法收集2024年1—12月中国人民解放军总医院第三医学中心收治的老年CG患者120例作为研究对象,经13 C-... 目的探究老年慢性胃炎(CG)患者幽门螺杆菌(Hp)感染与血清核因子-κB(NF-κB)、胃泌素17(G-17)、胰岛素样生长因子-1(IGF-1)的关系。方法收集2024年1—12月中国人民解放军总医院第三医学中心收治的老年CG患者120例作为研究对象,经13 C-尿素呼气试验,根据Hp感染情况分为感染组77例、未感染组43例。采集患者临床资料,检测并比较感染组、未感染组患者入院时血清NF-κB、G-17、IGF-1水平;经Logistic回归分析血清NF-κB、G-17、IGF-1水平与老年CG患者Hp感染的相关性;并绘制受试者工作特征(ROC)曲线,探究血清NF-κB、G-17、IGF-1水平对老年CG患者Hp感染的评估价值。结果感染组CG患者血清白介素-6(IL-6)、C反应蛋白(CRP)、NF-κB水平较未感染组高(t=6.944、6.154、7.967,P均<0.01),而血清G-17、IGF-1水平较未感染组低(t=8.118、5.392,P均<0.01)。经Logistic回归分析显示,血清G-17、IGF-1高表达是老年CG患者Hp感染的保护因素[OR(95%CI)=0.813(0.613~0.951)、0.725(0.567~0.927)],NF-κB、IL-6、CRP高表达是老年CG患者Hp感染的危险因素[OR(95%CI)=2.282(1.340~3.884)、2.278(1.060~4.896)、4.375(1.416~13.521)]。绘制ROC曲线显示,血清NF-κB、G-17、IGF-1单独及联合检测评估老年CG患者Hp感染的AUC值分别为0.887、0.794、0.711、0.902,三者联合检测能够提高评估价值,且高于各指标单独检测(Z/P=2.255/<0.001、2.157/<0.001、2.092/<0.001)。结论老年CG患者Hp感染与血清NF-κB、G-17、IGF-1水平有关,各项血清指标单独及联合检测对Hp感染具有一定的评估价值。 展开更多
关键词 慢性胃炎 幽门螺杆菌 胃泌素17 胰岛素样生长因子-1 核因子-ΚB 老年人
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Drosophila homolog of the intellectual disability-related long-chain acyl-CoA synthetase 4 is required for neuroblast proliferation 被引量:2
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作者 Mingyue Jia Danqing Meng +3 位作者 mo chen Tingting Li Yong Q.Zhang Aiyu Yao 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2019年第1期5-17,共13页
Mutations in long-chain acyl-CoA synthetase 4 (ACSL4) are associated with non-syndromic X-linked intellectual disability (ID). However, the neural functions of ACSL4 and how loss of ACSL4 leads to ID remain largely un... Mutations in long-chain acyl-CoA synthetase 4 (ACSL4) are associated with non-syndromic X-linked intellectual disability (ID). However, the neural functions of ACSL4 and how loss of ACSL4 leads to ID remain largely unexplored. We report here that mutations in Acsl, the Drosophila ortholog of human ACSL3 and ACSL4, result in developmental defects of the mushroom body (MB), the center of olfactory learning and memory. Specifically, Acsl mutants show fewer MB neuroblasts (Nbs) due to reduced proliferation activity and premature differentiation. Consistently, these surviving Nbs show reduced expression of cyclin E, a key regulator of the G1-to S-phase cell cycle transition, and nuclear mislocalization of the transcriptional factor Prospero, which is known to repress self-renewal genes and activate differentiating genes. Furthermore, RNA-seq analysis reveals downregulated Nb-and cell-cyclerelated genes and upregulated neuronal differentiation genes in Acsl mutant Nbs. As Drosophila Acsl and human ACSL4 are functionally conserved, our findings provide novel insights into a critical and previously unappreciated role of Acsl in neurogenesis and the pathogenesis of ACSL4-related ID. 展开更多
关键词 ACSL4 DROSOPHILA MUSHROOM body NEUROBLAST Neural stem cell PREMATURE differentiation
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Hemodynamics and vasoactive substance levels during renal congestion that occurs in the anhepatic phase of liver transplantation 被引量:2
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作者 Zhong-Xin Li Man-Cai Wang +6 位作者 You-cheng Zhang Jie Mao mo chen Rui Ni Feng-Xian Wei Gen-Nian Wang Ling-Yi Zhang 《World Journal of Gastroenterology》 SCIE CAS 2015年第18期5482-5487,共6页
AIM: To explore hemodynamics and vasoactive substance levels during renal vein congestion that occurs in the anhepatic phase of liver transplantation.METHODS: New Zealand rabbits received ligation of the hepatic pedic... AIM: To explore hemodynamics and vasoactive substance levels during renal vein congestion that occurs in the anhepatic phase of liver transplantation.METHODS: New Zealand rabbits received ligation of the hepatic pedicle, supra-hepatic vena cava and infrahepatic vena cava [anhepatic phase group(APH); n = 8], the renal veins(RVL; n = 8), renal veins and hepatic pedicle [with the inferior vena cava left open)(RVHP; n = 8)], or a sham operation(SOP; n = 8). Hemodynamic parameters(systolic, diastolic, and mean arterial blood pressures) and the levels of serum bradykinin(BK) and angiotensin Ⅱ(ANGII) were measured at baseline(0 min), and 10 min, 20 min, 30 min, and 45 min after the surgery. Correlation analyses were performed to evaluate the associations between hemodynamic parameters and levels of vasoactive substances.RESULTS:All experimental groups(APH,RVL,and RVHP)showed significant decreases in hemodynamic parameters(systolic,diastolic,and mean arterial blood pressures)compared to baseline levels,as well as compared to the SOP controls(P<0.05 for all).In contrast,BK levels were significantly increased compared to baseline in the APH,RVL,and RVHP groups at all time points measured(P<0.05 for all),whereas no change was observed in the SOP controls.There were no significant differences among the experimental groups for any measure at any time point.Further analyses revealed that systolic,diastolic,and mean arterial blood pressures were all negatively correlated with BK levels,and positively correlated with ANGII levels in the APH,RVL,and RVHP groups(P<0.05 for all).CONCLUSION:In the anhepatic phase of orthotopic liver transplantation,renal vein congestion significantly impacts hemodynamic parameters,which correlate with serum BK and ANGII levels. 展开更多
关键词 HEMODYNAMICS RENAL VEIN CONGESTION ORTHOTOPIC liver TRANSPLANTATION Anhepatic phase Vasoactive substances
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A Network Traffic Classification Model Based on Metric Learning 被引量:3
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作者 mo chen Xiaojuan Wang +3 位作者 Mingshu He Lei Jin Khalid Javeed Xiaojun Wang 《Computers, Materials & Continua》 SCIE EI 2020年第8期941-959,共19页
Attacks on websites and network servers are among the most critical threats in network security.Network behavior identification is one of the most effective ways to identify malicious network intrusions.Analyzing abno... Attacks on websites and network servers are among the most critical threats in network security.Network behavior identification is one of the most effective ways to identify malicious network intrusions.Analyzing abnormal network traffic patterns and traffic classification based on labeled network traffic data are among the most effective approaches for network behavior identification.Traditional methods for network traffic classification utilize algorithms such as Naive Bayes,Decision Tree and XGBoost.However,network traffic classification,which is required for network behavior identification,generally suffers from the problem of low accuracy even with the recently proposed deep learning models.To improve network traffic classification accuracy thus improving network intrusion detection rate,this paper proposes a new network traffic classification model,called ArcMargin,which incorporates metric learning into a convolutional neural network(CNN)to make the CNN model more discriminative.ArcMargin maps network traffic samples from the same category more closely while samples from different categories are mapped as far apart as possible.The metric learning regularization feature is called additive angular margin loss,and it is embedded in the object function of traditional CNN models.The proposed ArcMargin model is validated with three datasets and is compared with several other related algorithms.According to a set of classification indicators,the ArcMargin model is proofed to have better performances in both network traffic classification tasks and open-set tasks.Moreover,in open-set tasks,the ArcMargin model can cluster unknown data classes that do not exist in the previous training dataset. 展开更多
关键词 Metric learning ArcMargin network traffic classification CNNS
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Modeling the efects of fracture infll on frequency‑dependent anisotropy and AVO response of a fractured porous layer 被引量:2
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作者 Yan-Xiao He Xin-Long Li +3 位作者 Gen-Yang Tang Chun-Hui Dong mo chen Shang-Xu Wang 《Petroleum Science》 SCIE CAS CSCD 2021年第3期758-772,共15页
In a fractured porous hydrocarbon reservoir,wave velocities and refections depend on frequency and incident angle.A proper description of the frequency dependence of amplitude variations with ofset(AVO)signatures shou... In a fractured porous hydrocarbon reservoir,wave velocities and refections depend on frequency and incident angle.A proper description of the frequency dependence of amplitude variations with ofset(AVO)signatures should allow efects of fracture inflls and attenuation and dispersion of fractured media.The novelty of this study lies in the introduction of an improved approach for the investigation of incident-angle and frequency variations-associated refection responses.The improved AVO modeling method,using a frequency-domain propagator matrix method,is feasible to accurately consider velocity dispersion predicted from frequency-dependent elasticities from a rock physics modeling.And hence,the method is suitable for use in the case of an anisotropic medium with aligned fractures.Additionally,the proposed modeling approach allows the combined contributions of layer thickness,interbedded structure,impedance contrast and interferences to frequency-dependent refection coefcients and,hence,yielding seismograms of a layered model with a dispersive and attenuative reservoir.Our numerical results show bulk modulus of fracture fuid signifcantly afects anisotropic attenuation,hence causing frequencydependent refection abnormalities.These implications indicate the study of amplitude versus angle and frequency(AVAF)variations provides insights for better interpretation of refection anomalies and hydrocarbon identifcation in a layered reservoir with vertical transverse isotropy(VTI)dispersive media. 展开更多
关键词 Seismic anisotropy Fractured media Attenuation and dispersion AVO responses Frequency dependence
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小柴胡汤合香砂六君子汤对肝郁脾虚型慢性萎缩性胃炎患者胃黏膜病理积分改变与胃肠激素的影响 被引量:12
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作者 刘明贺 尹冬青 +6 位作者 张永青 白皛 莫晨 许莉 赵晶 郭建堂 冯书芳 《广州中医药大学学报》 CAS 2024年第9期2326-2332,共7页
【目的】探讨小柴胡汤合香砂六君子汤对肝郁脾虚型慢性萎缩性胃炎(CAG)患者胃黏膜病理积分改变与胃肠激素的影响。【方法】将156例肝郁脾虚型CAG患者随机分为对照组和观察组,每组各78例。对照组给予常规西医治疗,观察组在对照组的基础... 【目的】探讨小柴胡汤合香砂六君子汤对肝郁脾虚型慢性萎缩性胃炎(CAG)患者胃黏膜病理积分改变与胃肠激素的影响。【方法】将156例肝郁脾虚型CAG患者随机分为对照组和观察组,每组各78例。对照组给予常规西医治疗,观察组在对照组的基础上给予小柴胡汤合香砂六君子汤治疗,疗程为4周。观察2组患者治疗前后中医证候积分(胃脘胀痛、纳差便溏、四肢乏力、嗳气泛酸)、胃黏膜病理积分、胃肠激素[胃动素(MTL)、胃泌素(GAS)]水平的变化情况,比较2组患者的幽门螺旋杆菌(Hp)转阴率,评价2组患者的临床疗效和安全性。【结果】(1)治疗4周后,观察组的总有效率为93.59%(73/78),显著高于对照组的82.05%(64/78),组间比较,差异有统计学意义(P<0.05)。(2)治疗后,2组患者的胃脘胀痛、纳差便溏、四肢乏力、嗳气泛酸等各项中医证候积分均较治疗前明显降低(P<0.05),且观察组的降低幅度均明显优于对照组(P<0.05)。(3)治疗后,2组患者的胃黏膜病理积分均较治疗前明显降低(P<0.05),且观察组的降低幅度明显优于对照组(P<0.01)。(4)治疗4周后,观察组的Hp转阴率为91.03%(71/78),明显高于对照组的75.64%(59/78),组间比较,差异有统计学意义(P<0.05)。(5)治疗后,2组患者的血清GAS水平均较治疗前明显降低(P<0.05),血清MTL水平均较治疗前明显升高(P<0.05);且观察组对血清GAS水平的降低幅度及对血清MTL水平的升高幅度均明显优于对照组(P<0.05)。(6)2组患者用药期间的血、尿、大便常规以及肾、肝功能和心电图等安全性指标均无明显异常,也均未出现头晕、皮疹、胸闷等不良反应,具有较高的安全性。【结论】小柴胡汤合香砂六君子汤对肝郁脾虚型GAS的治疗效果显著,可有效减轻患者临床症状与胃黏膜病理改变,促进Hp转阴,其作用机制可能与调节胃肠激素水平有关。 展开更多
关键词 小柴胡汤 香砂六君子汤 肝郁脾虚型 慢性萎缩性胃炎 幽门螺旋杆菌转阴 胃黏膜病理积分 胃肠激素
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Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料研究进展 被引量:3
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作者 莫琛 向阳 +4 位作者 陈坤 张稳 彭志航 文瑾 曹建辉 《材料导报》 EI CAS CSCD 北大核心 2024年第18期1-9,共9页
目前,航空发动机等高温部件对热结构材料性能要求日渐严苛。Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料(Al_(2)O_(3)f/Al_(2)O_(3)CMCs)因具有优异的力学性能和抗氧化性,成为了热结构材料体系的研究热点。本文综述了Al_(2)O_(3)f/Al_(2)O_... 目前,航空发动机等高温部件对热结构材料性能要求日渐严苛。Al_(2)O_(3)f/Al_(2)O_(3)陶瓷基复合材料(Al_(2)O_(3)f/Al_(2)O_(3)CMCs)因具有优异的力学性能和抗氧化性,成为了热结构材料体系的研究热点。本文综述了Al_(2)O_(3)f/Al_(2)O_(3)CMCs的组成体系、主要性能和制备方法,并分析了该材料在相关领域的应用以及未来的发展趋势。 展开更多
关键词 Al_(2)O_(3)f /Al_(2)O_(3) CMCs 组成体系 抗氧化 制备方法 发展趋势
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高熵ReVO_(4)陶瓷与微波介电性能
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作者 陈德钦 莫尘 +4 位作者 农莲汀 崔洪波 王政锋 刘来君 李纯纯 《硅酸盐学报》 EI CAS CSCD 北大核心 2024年第9期2907-2914,共8页
采用固相反应法制备了3种高熵ReVO_(4)陶瓷,对其物相结构、微观形貌和振动特征采用X射线衍射、扫描电子显微镜和Raman光谱进行表征,并对微波介电性能进行了分析。结果表明:所有陶瓷样品均表现出空间群为I41/amd的四方锆石结构,致密的微... 采用固相反应法制备了3种高熵ReVO_(4)陶瓷,对其物相结构、微观形貌和振动特征采用X射线衍射、扫描电子显微镜和Raman光谱进行表征,并对微波介电性能进行了分析。结果表明:所有陶瓷样品均表现出空间群为I41/amd的四方锆石结构,致密的微观结构使其展现出良好的微波介电性能。采用Clausius-Mossotti公式解释了介电常数的变化,介电常数与离子极化率呈正相关;品质因数与填充因子具有相似的变化趋势;键价理论被用于反映晶格畸变的程度,并与谐振频率温度系数具有强关联性。 展开更多
关键词 高熵陶瓷 微波频率 介电性能 锆石结构 钒酸盐
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5A06铝合金变厚度板充液拉深变形与应力分析
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作者 莫琛 徐永超 苑世剑 《塑性工程学报》 CAS CSCD 北大核心 2024年第12期44-51,共8页
针对铝合金变厚度曲面件采用厚板旋压成形、再机械加工方法中存在的回弹大、易开裂问题,提出变厚度板拉深变形的成形方法,用于制造中间薄、外缘厚的整体椭球曲面构件。在变形过程中,变厚度板存在变形均匀性差、薄区易破裂的问题。针对... 针对铝合金变厚度曲面件采用厚板旋压成形、再机械加工方法中存在的回弹大、易开裂问题,提出变厚度板拉深变形的成形方法,用于制造中间薄、外缘厚的整体椭球曲面构件。在变形过程中,变厚度板存在变形均匀性差、薄区易破裂的问题。针对该问题,采用充液拉深成形方法,并在铝合金板坯表面设置弹性垫板。通过力学解析和拉深变形实验,研究液压和弹性垫板对变厚度板充液拉深变形的影响规律,分析充液拉深过程中的“有益摩擦效应”。结果表明,采用液压成形和施加聚氨酯弹性垫板相结合的工艺方法,能够提高变厚度板的拉深成形能力,增加最大拉深深度,改善薄区壁厚分布。当液压为5 MPa,弹性垫板厚度为3 mm时,可获得最大减薄率为7%的变厚度椭球曲面构件。 展开更多
关键词 铝合金 变厚度板 充液拉深 有益摩擦效应 壁厚分布
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纤维质量比对纤维多孔陶瓷复合材料性能的影响 被引量:1
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作者 莫琛 向阳 +4 位作者 罗萌 彭志航 文瑾 刘平 李海龙 《粉末冶金材料科学与工程》 2024年第6期477-485,504,共10页
纤维多孔陶瓷复合材料因其低密度、低热导率及相对较高的抗压强度,被广泛应用于飞行器的热防护领域。本研究采用氧化物纤维制备高效隔热材料,在不同烧结温度下制备不同纤维质量比(铝硅酸盐与超细石英纤维)的纤维多孔陶瓷复合材料,研究... 纤维多孔陶瓷复合材料因其低密度、低热导率及相对较高的抗压强度,被广泛应用于飞行器的热防护领域。本研究采用氧化物纤维制备高效隔热材料,在不同烧结温度下制备不同纤维质量比(铝硅酸盐与超细石英纤维)的纤维多孔陶瓷复合材料,研究纤维质量比对材料微观结构和宏观性能的影响。引入X射线计算机断层扫描(X-CT)技术,对复合材料微观结构进行非破坏性表征,利用三维重构软件对材料结构进行交互式阈值分析,对纤维分布进行重构,并使用纤维追踪分析对纤维取向进行模拟。结果表明:烧结温度较低时(900~1000℃),随铝硅酸盐纤维含量增加,复合材料的密度增大,孔隙率受纤维质量比的影响较小,抗压强度逐渐降低。烧结温度为900℃,铝硅酸盐纤维质量分数为20%时,复合材料抗压强度为1.99 MPa;而铝硅酸盐纤维质量分数为45%时,抗压强度降至0.8 MPa。烧结温度为1200℃时,两种纤维的强度均出现较大损伤,导致复合材料的抗压强度降低。纤维在微区内的分布并不均匀,部分区域存在较大孔隙,这些区域为复合材料强度薄弱区,容易失效。 展开更多
关键词 航天领域 氧化物纤维 纤维多孔陶瓷复合材料 热防护 X-CT技术
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Quafu-Qcover:Explore combinatorial optimization problems on cloud-based quantum computers 被引量:1
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作者 许宏泽 庄伟峰 +29 位作者 王正安 黄凯旋 时运豪 马卫国 李天铭 陈驰通 许凯 冯玉龙 刘培 陈墨 李尚书 杨智鹏 钱辰 靳羽欣 马运恒 肖骁 钱鹏 顾炎武 柴绪丹 普亚南 张翼鹏 魏世杰 增进峰 李行 龙桂鲁 金贻荣 于海峰 范桁 刘东 胡孟军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期104-115,共12页
We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and c... We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware backends.Quafu-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight graph.The core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA circuit.Quafu-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum computers.Compared to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed performance.Additionally,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum devices.This ensures that computational tasks can be assigned to connected physical qubits with the highest fidelity.The Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous processing.Moreover,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization problems.We hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers. 展开更多
关键词 quantum cloud platform combinatorial optimization problems quantum software
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Quafu-RL:The cloud quantum computers based quantum reinforcement learning 被引量:1
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作者 靳羽欣 许宏泽 +29 位作者 王正安 庄伟峰 黄凯旋 时运豪 马卫国 李天铭 陈驰通 许凯 冯玉龙 刘培 陈墨 李尚书 杨智鹏 钱辰 马运恒 肖骁 钱鹏 顾炎武 柴绪丹 普亚南 张翼鹏 魏世杰 曾进峰 李行 龙桂鲁 金贻荣 于海峰 范桁 刘东 胡孟军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期29-34,共6页
With the rapid advancement of quantum computing,hybrid quantum–classical machine learning has shown numerous potential applications at the current stage,with expectations of being achievable in the noisy intermediate... With the rapid advancement of quantum computing,hybrid quantum–classical machine learning has shown numerous potential applications at the current stage,with expectations of being achievable in the noisy intermediate-scale quantum(NISQ)era.Quantum reinforcement learning,as an indispensable study,has recently demonstrated its ability to solve standard benchmark environments with formally provable theoretical advantages over classical counterparts.However,despite the progress of quantum processors and the emergence of quantum computing clouds,implementing quantum reinforcement learning algorithms utilizing parameterized quantum circuits(PQCs)on NISQ devices remains infrequent.In this work,we take the first step towards executing benchmark quantum reinforcement problems on real devices equipped with at most 136 qubits on the BAQIS Quafu quantum computing cloud.The experimental results demonstrate that the policy agents can successfully accomplish objectives under modified conditions in both the training and inference phases.Moreover,we design hardware-efficient PQC architectures in the quantum model using a multi-objective evolutionary algorithm and develop a learning algorithm that is adaptable to quantum devices.We hope that the Quafu-RL can be a guiding example to show how to realize machine learning tasks by taking advantage of quantum computers on the quantum cloud platform. 展开更多
关键词 quantum cloud platform quantum reinforcement learning evolutionary quantum architecture search
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2219铝合金变厚度板坯充液拉深工艺研究
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作者 莫琛 贾春莉 +1 位作者 徐永超 苑世剑 《航天制造技术》 2024年第4期30-35,共6页
针对运载火箭燃料贮箱整体箱底采用厚板旋压、再机械加工的方法存在的易开裂、加工量大的问题,提出了先机械加工获得变厚度板坯,再拉深成形的制造方法。圆形变厚度板坯具有中间薄、外缘厚的形状特点,成形中存在薄区易开裂的问题,为此采... 针对运载火箭燃料贮箱整体箱底采用厚板旋压、再机械加工的方法存在的易开裂、加工量大的问题,提出了先机械加工获得变厚度板坯,再拉深成形的制造方法。圆形变厚度板坯具有中间薄、外缘厚的形状特点,成形中存在薄区易开裂的问题,为此采用充液拉深并结合弹性垫板的成形方法。通过数值模拟和工艺实验,研究液压和弹性垫板对变厚度板坯拉深成形壁厚及应变分布的影响规律。研究结果表明,增大液压和设置弹性辅助板能够增大界面摩擦,降低拉深试件的最大壁厚减薄率,改善薄区的壁厚分布。当液压为5.2 MPa、弹性辅助板厚度为5 mm时,试件最大壁厚减薄率为8.8%,相较于普通拉深降低34%。 展开更多
关键词 2219铝合金 充液拉深 变厚度板坯 壁厚分布
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Apoptosis-resistant megakaryocytes produce large and hyperreactive platelets in response to radiation injury
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作者 Chang-Hong Du Yi-Ding Wu +15 位作者 Ke Yang Wei-Nian Liao Li Ran Chao-Nan Liu Shu-Zhen Zhang Kuan Yu Jun chen Yong Quan mo chen Ming-Qiang Shen Hong Tang Shi-Lei chen Song Wang Jing-Hong Zhao Tian-Min cheng Jun-Ping Wang 《Military Medical Research》 CSCD 2024年第6期797-817,共21页
Background:The essential roles of platelets in thrombosis have been well recognized.Unexpectedly,thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological,physical and chemical origins,whic... Background:The essential roles of platelets in thrombosis have been well recognized.Unexpectedly,thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological,physical and chemical origins,which could be suffered by military personnel and civilians during chemical,biological,radioactive,and nuclear events.Especially,thrombosis is considered a major cause of mortality from radiation injury-induced thrombocytopenia,while the underlying pathogenic mechanism remains elusive.Methods:A mouse model of radiation injury-induced thrombocytopenia was built by exposing mice to a sublethal dose of ionizing radiation(IR).The phenotypic and functional changes of platelets and megakaryocytes(MKs)were determined by a comprehensive set of in vitro and in vivo assays,including flow cytometry,flow chamber,histopathology,Western blotting,and chromatin immunoprecipitation,in combination with transcriptomic analysis.The molecular mechanism was investigated both in vitro and in vivo,and was consolidated using MK-specific knockout mice.The translational potential was evaluated using a human MK cell line and several pharmacological inhibitors.Results:In contrast to primitive MKs,mature MKs(mMKs)are intrinsically programmed to be apoptosis-resistant through reprogramming the Bcl-xL-BAX/BAK axis.Interestingly,mMKs undergo minority mitochondrial outer membrane permeabilization(MOMP)post IR,resulting in the activation of the cyclic GMP-AMP synthase-stimulator of IFN genes(cGAS-STING)pathway via the release of mitochondrial DNA.The subsequent interferon-β(IFN-β)response in mMKs upregulates a GTPase guanylate-binding protein 2(GBP2)to produce large and hyperreactive platelets that favor thrombosis.Further,we unmask that autophagy restrains minority MOMP in mMKs post IR.Conclusions:Our study identifies that megakaryocytic mitochondria-cGAS/STING-IFN-β-GBP2 axis serves as a fundamental checkpoint that instructs the size and function of platelets upon radiation injury and can be harnessed to treat platelet pathologies. 展开更多
关键词 Radiation injury THROMBOCYTOPENIA Platelet size Platelet hyperreactivity Megakaryocytes(MKs)
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Cdc42及YAP检测对非瓣膜性心房颤动诊断的相关性研究 被引量:2
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作者 唐碧 徐庆梅 +6 位作者 朱飞宇 莫辰 张恒 宣玲 汤阳 王闯 康品方 《蚌埠医学院学报》 CAS 2021年第10期1349-1353,共5页
目的:探讨非瓣膜性心房颤动(房颤)病人血清细胞分裂周期蛋白42(Cdc42)和转录辅助激活因子Yes相关蛋白(YAP)表达水平及临床意义。方法:选取81例非瓣膜性房颤病人(其中阵发性房颤38例,持续性房颤43例)为研究对象,40例同期住院非房颤病人... 目的:探讨非瓣膜性心房颤动(房颤)病人血清细胞分裂周期蛋白42(Cdc42)和转录辅助激活因子Yes相关蛋白(YAP)表达水平及临床意义。方法:选取81例非瓣膜性房颤病人(其中阵发性房颤38例,持续性房颤43例)为研究对象,40例同期住院非房颤病人为对照组,采用酶联免疫吸附法检测血清Cdc42及YAP表达水平。同时结合相关血清学指标,统计分析非瓣膜性房颤病人的Cdc42及YAP水平,探讨两者与非瓣膜性房颤诊断的关系。结果:同对照组相比,房颤病人CRP、国家标准化比值、D-二聚体、LAD水平增高,LVEF水平降低,差异有统计学意义(P<0.01),房颤病人中,持续性房颤病人较阵发性房颤病人LAD增大,LVEF降低,差异有统计学意义(P<0.01);同对照组相比,房颤病人血清Cdc42和YAP表达水平增高,差异有统计学意义(P<0.01),持续性房颤病人血清Cdc42和YAP表达水平较阵发性房颤病人升高,差异有统计学意义(P<0.01和P<0.05)。Pearson相关性分析结果显示,房颤病人血清Cdc42和YAP水平与D-二聚体、LAD呈正相关(P<0.05~P<0.01),与左心室射血分数呈负相关(P<0.01);Cdc42及YAP二者联合诊断房颤的受试者工作特征曲线下面积较单独诊断提高(P<0.05)。D-二聚体、LAD、Cdc42及YAP表达增加、LVEF减小均为影响房颤的危险因素(P<0.05~P<0.01)。结论:房颤病人血清Cdc42及YAP异常表达,可能参与房颤心房结构重构的发生发展,可用作早期潜在辅助诊断房颤的指标。 展开更多
关键词 心房颤动 心房纤维化 细胞分裂周期蛋白42 Yes相关蛋白
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西藏各地市健康人群H.pylori菌感染状况分析 被引量:5
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作者 陈茉 刘超 +4 位作者 李晓萍 宦徽 胡仁伟 吴浩 邓凯 《世界华人消化杂志》 CAS 2018年第31期1825-1831,共7页
目的了解目前西藏地区人群幽门螺旋杆菌(Helicobacter pylori, H. pylori)的感染状况,为西藏地区幽门螺杆菌感染的防治提供临床数据.方法回顾2017年于西藏自治区人民政府驻成都办事处医院就诊且同时完成13C-尿素呼气试验的西藏地区体检... 目的了解目前西藏地区人群幽门螺旋杆菌(Helicobacter pylori, H. pylori)的感染状况,为西藏地区幽门螺杆菌感染的防治提供临床数据.方法回顾2017年于西藏自治区人民政府驻成都办事处医院就诊且同时完成13C-尿素呼气试验的西藏地区体检者,收集临床资料、常居留地及H. pylori检测结果等.结果共纳入931例病例, H. pylori总体阳性率为480/931(51.6%,95%C I:48.3%-54.8%),其中藏族586例, H.pylori阳性率为331/586(56.5%,95%CI:52.5%-60.5%);汉族345例, H.pylori阳性率为149/345(43.2%,95%CI:37.9%-48.4%).藏汉族之间H.pylori阳性率存在显著差异(P <0.001).西藏地区各地市的H. pylori阳性率分别为:拉萨市99/219(45.2%,95%C I:38.6%-51.8%),昌都市213/372(57.3%,95%C I:52.2%-62.3%),林芝市56/110(50.9%,95%CI:41.4%-60.4%),山南市25/63(39.7%,95%CI:27.3%-52.1%),日喀则市21/51(41.2%,95%C I:27.2%-55.2%),那曲地区17/40(42.5%,95%C I:26.5%-58.5%),阿里地区49/76(64.5%,95%C I:53.5%-75.5%),各地市之间的H.pylori阳性率存在差异(P=0.002).结论西藏地区H. pylori现患率已下降趋于全国水平,藏汉族之间现患率存在差异,各地市H. pylori现患率亦存在差异. 展开更多
关键词 幽门螺旋杆菌感染 现患率 13C-尿素呼气试验 西藏 回顾性研究
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