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左心室肥厚伴肢体导联低电压在心脏淀粉样变中的诊断价值

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中华心力衰竭和心肌病杂志(中英文) 2024年第2期08卷 89-94页

作者：李敏孙显东王宇楠王珂内蒙古医科大学赤峰临床医学院赤峰市医院心内科赤峰大连医科大学附属第一医院心内科大连

目的评估超声心动图检查左心室增厚(LVH)与心电图检查肢体导联低电压在心脏淀粉样变(CA)中的诊断价值。方法收集自2000年11月至2018年11月在大连医科大学附属第一医院住院, 超声心动图检查提示LVH, 伴或不伴有心动图肢体导联低电压的患... 详细信息

目的评估超声心动图检查左心室增厚(LVH)与心电图检查肢体导联低电压在心脏淀粉样变(CA)中的诊断价值。方法收集自2000年11月至2018年11月在大连医科大学附属第一医院住院, 超声心动图检查提示LVH, 伴或不伴有心动图肢体导联低电压的患者, 根据出院诊断分为确诊CA(组1)、原发性非梗阻性肥厚型心肌病(HCM)(组2)、中度或重度主动脉瓣狭窄(AS)(组3)、高血压性心脏病(组4)及可疑CA(组5)共5组。将组2、组3和组4患者合并为非CA患者, 与组1患者比较, 评估超声心动图检查LVH和心电图检查肢体导联低电压对CA的诊断价值。将组5(可疑CA患者)与组1(确诊CA患者)进行比较, 评估两组患者临床特征的差异。结果本研究共纳入了128例患者, 确诊CA(组1)患者16例, 原发性非梗阻性HCM(组2)患者32例, 中度或重度AS(组3)患者30例, 高血压性心脏病(组4)患者30例, 可疑CA(组5)患者20例。以超声心动图检查LVH合并心电图肢体导联低电压作为初步诊断CA的判断标准, 诊断灵敏度、特异度、准确率、漏诊率、误诊率、阳性预测值、阴性预测值、阳性似然比、阴性似然比分别为81.2%、97.8%、95.4%、18.8%、2.2%、86.7%、96.8%、36.9、0.2。组1和组5患者心电图和超声心动图指标比较差异无统计学意义(P均>0.05)。结论以"电"与"结构"不匹配现象, 作为初步诊断具有LVH的CA的指标较可靠, 灵敏度和阳性预测值均较高(>80%), 有利于临床上高度怀疑CA患者的诊断, 减少漏诊率;该判断标准的特异度和阴性预测值更高(均>95%), 具有很好的排除诊断和减少误诊率的临床实用价值。

关键词：心脏淀粉样变左心室肥厚肢体导联低电压诊断鉴别诊断

逆向射流对高超声速升力体构型的减阻特性研究

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宇航学报 2024年第6期45卷 881-892页

作者：王林王宇楠罗振兵周岩谢玮刘强国防科技大学空天科学学院长沙410073

在高超声速飞行过程中,飞行器往往会面临巨大的阻力,严重限制了其飞行性能,并增加了飞行器表面的热负荷和材料应力。针对这一问题,通过数值模拟系统地分析了射流孔数量、位置和攻角对升力体减阻性能的影响。研究结果表明,随着射流孔数... 详细信息

在高超声速飞行过程中,飞行器往往会面临巨大的阻力,严重限制了其飞行性能,并增加了飞行器表面的热负荷和材料应力。针对这一问题,通过数值模拟系统地分析了射流孔数量、位置和攻角对升力体减阻性能的影响。研究结果表明,随着射流孔数量的增加,整体减阻率显著提高,有效降低了升力体头部的高压区域,但也导致四周流场的不稳定性增强。射流孔位置对激波脱体距离和“气膜”厚度具有重要影响。此外,增大攻角会导致整体减阻率下降,但对局部减阻率影响较小,同时会增加上下壁面之间的压差。进一步比较研究发现,在20 km和55 km高空条件下,这3种因素对减阻性能的影响规律保持一致。研究结果为设计高效减阻方案提供了重要参考。

关键词：逆向射流减阻升力体高超声速飞行器激波

小果型西瓜优化复种豇豆、结球甘蓝周年栽培方法

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中国种业 2024年第1期 152-155页

作者：王宇楠郭尚张作刚王海珍山西农业大学太原030031

为解决设施春提早小果型西瓜种植中茬口、土壤地力等的不合理利用问题,总结出一种小果型西瓜优化复种豇豆、结球甘蓝周年栽培方法,通过选择最适品种,合理安排茬口,适时精细化育苗,固氮菌剂的施用,茬口间高温闷棚等技术的改进,实现温室... 详细信息

为解决设施春提早小果型西瓜种植中茬口、土壤地力等的不合理利用问题,总结出一种小果型西瓜优化复种豇豆、结球甘蓝周年栽培方法,通过选择最适品种,合理安排茬口,适时精细化育苗,固氮菌剂的施用,茬口间高温闷棚等技术的改进,实现温室内早春茬种植小果型西瓜后再复种豇豆、结球甘蓝的周年高效生态循环生产模式,并对调节温室地力,培土固氮起到积极的作用。

关键词：小果型西瓜复种豇豆结球甘蓝周年栽培

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引流技术在普通外科领域的应用

齐齐哈尔医学院学报 2024年第2期45卷 188-191页

作者：宋泽辉王宇男商莹联勤保障部队第九六一医院普通外科黑龙江齐齐哈尔161000

引流技术作为一种便捷有效的治疗手段始终被外科临床医生青睐,采用特殊材料,依据吸附、虹吸等物理原理,结合人类机体生物学效应,将人体内多余的气液体排出体外从而达到治疗目的。通过近几个世纪的发展,目前外科引流技术已经在外科治疗... 详细信息

引流技术作为一种便捷有效的治疗手段始终被外科临床医生青睐,采用特殊材料,依据吸附、虹吸等物理原理,结合人类机体生物学效应,将人体内多余的气液体排出体外从而达到治疗目的。通过近几个世纪的发展,目前外科引流技术已经在外科治疗中占有及其重要的地位,随着外科微创技术的发展和快速康复治疗理念的普及,其也在不断的发展和进步,尤其是引流管引流技术的发展尤为迅速。

关键词：外科引流适应症并发症拔除指征

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某电厂中调门预启阀碟断裂原因分析

东北电力技术 2024年第7期45卷 54-57页

作者：王天鹏张显武曹琳王宇楠国网辽宁省电力有限公司电力科学研究院辽宁沈阳110006 辽宁东科电力有限公司辽宁沈阳110179

某火电机组中调门预启阀碟发生断裂,采用宏观形貌、力学性能测试、化学成分分析、金相组织观察和扫描电镜等试验方法对其断裂原因进行分析。研究表明,阀碟材料的化学成分、强度、组织等指标均满足要求,延伸率、冲击韧性值均低于要求值... 详细信息

某火电机组中调门预启阀碟发生断裂,采用宏观形貌、力学性能测试、化学成分分析、金相组织观察和扫描电镜等试验方法对其断裂原因进行分析。研究表明,阀碟材料的化学成分、强度、组织等指标均满足要求,延伸率、冲击韧性值均低于要求值。分析显示σ相析出对材料的基体产生了明显弱化作用,降低了构件整体强度。由于阀杆与防旋转销子存在微动摩擦及碰撞,且销子和阀碟径向间隙变小产生附加应力,预启阀碟在销孔内应力集中区域发生开裂,并呈现脆性扩展趋势。随着裂纹不断扩展,最终导致阀碟断裂。该研究可为存在类似问题的电厂提供参考。

关键词：中调门预启阀碟失效分析

Far-from-equilibrium electrosynthesis ramifies high-entropy alloy for alkaline hydrogen evolution

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Journal of Materials Science & Technology 2023年第35期166卷 234-240页

作者： yunan wang Hao Yang Zhe Zhang Xiangying Meng Tao Cheng Gaowu Qin Song Li Key Lab for Anisotropy and Texture of Materials(MoE) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

High-entropy alloys(HEAs)provide an ideal platform for developing highly active electrocatalysts and investigating the synergy of mixed ***-from-equilibrium synthesis holds great potential for fabricating HEAs at the nanoscale by rapidly shifting the thermodynamic conditions and manipulat-ing the growth *** far-from-equilibrium synthesis of nanomaterials has been successful un-der thermochemical conditions,it is markedly challenging under electrochemical environments,as the use of an electrolyte limits the accessible temperature window and the temporal tunability of ***,we demonstrate that applying a large electrochemical overpotential would create a far-from-equilibrium condition as changing the temperature of the system by considering the equation △G=△H−T△S+nF△ψ.An electrochemical far-from-equilibrium approach is thus setup for construct-ing hierarchical and self-supporting high-entropy alloy *** large overpotential drives the simultaneous reduction of multiple cations and the subsequent formation of a single-phase *** a proof-of-concept,hierarchical Fe_(0.22)Co_(0.18)Ni_(0.18)Cr_(0.14)Cu_(0.28)was fabricated and used as an electrocatalyst for the hydrogen evolution reaction in alkaline *** noble-metal-free HEA exhibits an overpoten-tial of 84 mV at a current density of 10 mA cm^(-2),which is among the lowest even compared to noble metal-based *** work opens a new avenue for building a variety of HEAs for energy and catalysis applications.

关键词： High-entropy alloys Nanostructures Electrocatalysis Hydrogen evolution reaction Far-from-equilibrium synthesis

Enhancing charge storage of O-doped perovskite fluorides via in-situ electrochemical oxidation for high-performance potassium-ion capacitors

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Journal of Materials Science & Technology 2023年第27期158卷 111-120页

作者： Jing Zhao Zicheng Cai Yue Fan yunan wang Yu Song Jie Liu Shuangwen Li Di Guo Xiaoxia Liu Department of Chemistry Northeastern UniversityShenyang 110819China School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China School of Materials Engineering North China Institute of Aerospace EngineeringLangfang 065000China

Potassium ion capacitors(PICs)are regarded as promising large-scale aqueous energy storage ***,due to the poor K^(+)transport kinetics and the structural instability of the cathode materials,the key issues of limited energy density and poor cyclic stability are obstacles to the in-depth growth of ***,a novel O-doped perovskite fluoride is demonstrated via an in-situ electrochemical oxidation strategy as the cathode for PICs,introducing additional defects that improve the capacitance and facilitate the reaction kinetics of the *** the electrochemical oxidation process,it is discovered that the perovskite fluoride crystal tends to transform into disordered O-doped KMnF 3(K_(x)MnF_(y)O_(z)),realizing a structural reconstruction at the electrode material/electrolyte *** First-principles calculations based on density functional theory(DFT)are performed to confirm that the improved electrical conduc-tivity and low ionic adsorption energy may be ascribed to the substitution of oxygen for *** obtained K_(1.14)MnF_(1.17)O_(1.26) cathode achieves a high specific capacitance of 694 F g^(-1) at 1 A g^(-1),as well as high capacitance retention of 91.3%after 10,000 charge/discharge cycles in mild K_(2)SO_(4) *** study provides an effective strategy to improve the capacitive performance of perovskite fluoride cathode materials in electrochemical energy storage.

关键词： Perovskite fluorides O-doped Potassium-ion capacitors Charge storage mechanism

The role of m^(6)A RNA methylation in autoimmune diseases: Novel therapeutic opportunities

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Genes & Diseases 2024年第1期11卷 252-267页

作者： yunan Shan Wei Chen Yanbin Li The First Clinical Medical College Shandong University of Traditional Chinese MedicineJinanShandong 250013China Department of Neurology The First Affiliated Hospital of Shandong First Medical University&Shandong Provincial Qjanfoshan HospitalShandong Institute of NeuroimmunologyShandong Key Laboratory of Rheumatic Disease and Translational MedicineJinanShandong 250013China Department of Gastroenterology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

N6-methyladenosine m^(6)A modifications,as one of the most common forms of in-ternal RNA chemical modifications in eukaryotic cells,have gained increasing attention in recent *** m^(6)A RNA modifications exert various crucial roles in various biological pro-cesses,such as embryonic development,neurogenesis,circadian rhythms,and *** advances have highlighted that m^(6)A RNA modification plays an important role in im-mune response,especially in the initiation and progression of autoimmune *** this re-view,we summarized the regulatory mechanisms of m^(6)A methylation and its biological functions in the immune system and mainly focused on recent progress in research on the po-tential role of m^(6)A RNA methylation in the pathogenesis of autoimmune diseases,thus providing possible biomarkers and potential targets for the prevention and treatment of auto-immunediseases.

关键词： Adaptive immunity Autoimmune diseases Innate immunity Immune response m^(6)A RNA methylation

Adaptive State-Dependent Diffusion for Derivative-Free Optimization

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1241-1269页

作者： Bjorn Engquist Kui Ren yunan Yang Department of Mathematics and the Oden Institute The University of TexasAustinTX 78712USA Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY10027USA Department of Mathematics Cornell UniversityIthacaNY 14853USA

This paper develops and analyzes a stochastic derivative-free optimization strategy.A key feature is the state-dependent adaptive *** prove global convergence in probability with algebraic rate and give the quantitative results in numerical examples.A striking fact is that convergence is achieved without explicit information of the gradient and even without comparing different objective function values as in established methods such as the simplex method and simulated *** can otherwise be compared to annealing with state-dependent temperature.

关键词： Derivative-free optimization Global optimization Adaptive diffusion Stationary distribution Fokker-Planck theory