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焦炉煤气脱硫废液中CN^(-)、SCN^(-)的测定
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作者 刘钲楠 付本全 +3 位作者 胡辉 曾为一 王丽娜 黄浩 《中国无机分析化学》 CAS 北大核心 2024年第10期1369-1377,共9页
为解决焦炉煤气脱硫产生的废水中多种离子干扰导致CN^(-)、SCN^(-)难以准确检测问题,基于分析化学和消除离子间干扰的基本原理,提出常规无机化学分析方法检测真空碳酸钾法焦化煤气脱硫产生的碱性废液中CN^(-)、SCN^(-),包括预处理方法... 为解决焦炉煤气脱硫产生的废水中多种离子干扰导致CN^(-)、SCN^(-)难以准确检测问题,基于分析化学和消除离子间干扰的基本原理,提出常规无机化学分析方法检测真空碳酸钾法焦化煤气脱硫产生的碱性废液中CN^(-)、SCN^(-),包括预处理方法和仪器检测步骤。其中,易释放氰化物通过第一次酸化蒸馏,第二次沉淀配合蒸馏的预处理方法实现了消除SCN^(-)、S^(2-)、SO_(3)^(2-)和S_(2)O_(3)^(2-)对硝酸银容量法检测CN^(-)过程中的干扰,再利用硝酸银容量法测定CN^(-)浓度。利用沉淀、萃取和配合的预处理方法实现CN^(-)、S^(2-)和苯酚对SCN^(-)检测干扰的消除,在此基础上再利用硫氰酸铁分光光度法测定SCN^(-)。还给出了更明确的检测步骤和影响因素讨论,方法可用于复杂环境样品中CN^(-)、SCN^(-)的检测,为焦炉荒煤气脱硫过程控制和废水处理提供更好的技术支持。 展开更多
关键词 氰根 硫氰酸根 干扰 荒煤气 脱硫废液
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Memristor’s characteristics: From non-ideal to ideal
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作者 孙帆 粟静 +2 位作者 李杰 段书凯 胡小方 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期504-508,共5页
Memristor has been widely studied in the field of neuromorphic computing and is considered to be a strong candidate to break the von Neumann bottleneck. However, the non-ideal characteristics of memristor seriously li... Memristor has been widely studied in the field of neuromorphic computing and is considered to be a strong candidate to break the von Neumann bottleneck. However, the non-ideal characteristics of memristor seriously limit its practical application. There are two sides to everything, and memristors are no exception. The non-ideal characteristics of memristors may become ideal in some applications. Genetic algorithm(GA) is a method to search for the optimal solution by simulating the process of biological evolution. It is widely used in the fields of machine learning, combinatorial optimization,and signal processing. In this paper, we simulate the biological evolutionary behavior in GA by using the non-ideal characteristics of memristors, based on which we design peripheral circuits and path planning algorithms based on memristor networks. The experimental results show that the non-ideal characteristics of memristor can well simulate the biological evolution behavior in GA. 展开更多
关键词 MEMRISTOR non-ideal characteristic genetic algorithm path planning
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Effect of spin on the instability of THz plasma waves in field-effect transistors under non-ideal boundary conditions
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作者 张丽萍 李佳妮 +1 位作者 冯江旭 苏俊燕 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第12期24-30,共7页
Terahertz(THz) radiation can be generated due to the instability of THz plasma waves in field-effect transistors(FETs). In this work, we discuss the instability of THz plasma waves in the channel of FETs with spin and... Terahertz(THz) radiation can be generated due to the instability of THz plasma waves in field-effect transistors(FETs). In this work, we discuss the instability of THz plasma waves in the channel of FETs with spin and quantum effects under non-ideal boundary conditions. We obtain a linear dispersion relation by using the hydrodynamic equation, Maxwell equation and spin equation. The influence of source capacitance, drain capacitance, spin effects, quantum effects and channel width on the instability of THz plasma waves under the non-ideal boundary conditions is investigated in great detail. The results of numerical simulation show that the THz plasma wave is unstable when the drain capacitance is smaller than the source capacitance;the oscillation frequency with asymmetric boundary conditions is smaller than that under non-ideal boundary conditions;the instability gain of THz plasma waves becomes lower under non-ideal boundary conditions. This finding provides a new idea for finding efficient THz radiation sources and opens up a new mechanism for the development of THz technology. 展开更多
关键词 the instability of THz plasma waves spin effects non-ideal boundary conditions quantum effects field-effect transistors
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SCN9A基因突变引起原发性红斑肢痛症1例及文献复习
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作者 孙翠翠 杨赛 +3 位作者 郑航 梁云生 林志淼 陈永锋 《皮肤性病诊疗学杂志》 2024年第1期15-21,共7页
目的 报告1例以双小腿、双足灼痛伴潮红、皮温升高为主要临床特征的原发性红斑肢痛症(PEM),并寻找其致病基因和突变位点,探索有效治疗方法。方法 收集患者临床资料,采集患者及亲属外周血,提取基因组DNA,进行遗传皮肤病基因二代测序,并用... 目的 报告1例以双小腿、双足灼痛伴潮红、皮温升高为主要临床特征的原发性红斑肢痛症(PEM),并寻找其致病基因和突变位点,探索有效治疗方法。方法 收集患者临床资料,采集患者及亲属外周血,提取基因组DNA,进行遗传皮肤病基因二代测序,并用Sanger测序验证可疑致病基因突变。对该患者予以阿司匹林抗炎,苯甲酸利扎曲普坦片、盐酸美西律片、卡马西平片、局部注射肉毒毒素镇痛,外用复方多粘菌素B软膏等以及冷却疗法进行综合治疗。结果 在患者外周血基因组DNA中检测到SCN9A:NM_002977.3:c.688+142G>A或SCN9A:ENST00000375387.4:c.626G>A(p.Gly209Asp)杂合变异,其姐姐、叔叔2、堂兄检测出相同突变。结合致病基因及临床表现,患者被诊断为PEM。治疗后,患者疼痛明显缓解。结论 SCN9A基因的NM_002977.3:c.688+142G>A内含子突变或c.626G>A(p.Gly209Asp)错义突变是本例PEM的致病原因。阿司匹林、苯甲酸利扎曲普坦片、盐酸美西律片、卡马西平片及局部治疗的联合应用可有效控制PEM症状,减少急性发作频率,改善预后。 展开更多
关键词 原发性红斑肢痛症 scn9A基因 Nav1.7通道
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SCN2A基因突变相关癫痫患儿外周血miRNA-15a-5p表达变化及其与病情的关系
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作者 陈娇 张园 +3 位作者 赵家强 王慧杰 刘莉 刘晓鸣 《山东医药》 CAS 2024年第15期56-59,共4页
目的观察SCN2A基因突变相关癲痫患儿外周血miRNA-15a-5p水平变化,分析外周血miRNA-15a-5p相对表达量与SCN2A基因突变相关癲痫患儿病情的相关性。方法纳入同期住院癫痫患儿20例,其中SCN2A基因突变的癫痫患儿10例(突变组)、非SCN2A基因突... 目的观察SCN2A基因突变相关癲痫患儿外周血miRNA-15a-5p水平变化,分析外周血miRNA-15a-5p相对表达量与SCN2A基因突变相关癲痫患儿病情的相关性。方法纳入同期住院癫痫患儿20例,其中SCN2A基因突变的癫痫患儿10例(突变组)、非SCN2A基因突变的癫痫患儿(非突变组)10例;突变组中,癫痫控制良好4例、难治性癫痫6例;SCN2A基因突变位点在钠离子通道的关键区6例、连接区4例。另择同期体检健康儿童10例作为对照组。采用qRT-PCR检测上述三组外周血miRNA-15a-5p。采用Spearman相关分析外周血miRNA-15a-5p水平与癫痫患儿病情的相关性。结果与非突变组和对照组相比,突变组患儿外周血miRNA-15a-5p相对表达量升高(P<0.001);在突变组中,与SCN2A基因突变位点在钠离子通道的连接区患儿相比,在关键区的患儿外周血miRNA-15a-5p表达升高,且表达量与突变位点是否在关键区相关(r=0.71,P<0.05)。与癫痫控制良好患儿相比,难治性癫痫患儿外周血miRNA-15a-5p相对表达量升高,且表达量与患儿病情相关(r=0.85,P<0.05)。结论SCN2A基因突变相关癫痫患儿外周血中miRNA-15a-5p相对表达量升高,其表达量高的癫痫患儿病情重。 展开更多
关键词 微小RNA-15a-5p 癫痫 难治性癫痫 scn2A基因突变
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基于SCN数据模型的SISO非线性自适应控制
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作者 代伟 张政煊 +1 位作者 杨春雨 马小平 《自动化学报》 EI CAS CSCD 北大核心 2024年第10期2002-2012,共11页
针对一类难以建立精确模型的单输入单输出(Single-input single-output,SISO)非线性离散动态系统,提出了一种数据驱动模型的自适应控制方法.所提方法首先设计具有直链与增强结构的随机配置网络(Stochastic configuration network,SCN),... 针对一类难以建立精确模型的单输入单输出(Single-input single-output,SISO)非线性离散动态系统,提出了一种数据驱动模型的自适应控制方法.所提方法首先设计具有直链与增强结构的随机配置网络(Stochastic configuration network,SCN),建立了一种可同时表征非线性系统低阶线性部分与高阶非线性项(未建模动态)的数据驱动模型,并采用增量学习方法与监督机制,对模型结构与模型参数进行同步更新优化,保证了数据驱动模型的无限逼近能力,解决了传统自适应控制采用交替辨识算法存在的建模精度低、模型收敛性无法保证的问题.进而利用直链部分与增强部分,分别设计了线性控制器及虚拟未建模动态补偿器,建立了基于SCN数据驱动模型的自适应控制新方法,分析了其稳定性与收敛性,通过数值仿真实验和采用交替辨识算法的传统自适应控制方法进行对比,实验结果表明了所提方法的有效性. 展开更多
关键词 自适应控制 随机配置网络 监督机制 未建模动态 数据驱动模型
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SCN1A rs6732655A/T polymorphism:Diagnostic and therapeutic insights for drug-resistant epilepsy
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作者 Aroop Viswas Pradeep K Dabla +4 位作者 Dharmsheel Shrivastav Swapan Gupta Manisha Yadav Subhash Yadav Bidhan Chandra Koner 《World Journal of Experimental Medicine》 2024年第3期72-79,共8页
BACKGROUND A significant subset of individuals with epilepsy fails to respond to currently available antiepileptic drugs,resulting in heightened mortality rates,psychosocial challenges,and a diminished quality of life... BACKGROUND A significant subset of individuals with epilepsy fails to respond to currently available antiepileptic drugs,resulting in heightened mortality rates,psychosocial challenges,and a diminished quality of life.Genetic factors,particularly within the SCN1A gene,and the pro-inflammatory cytokine response is important in intricating the drug resistance in idiopathic epilepsy cases.In this extended study,we determined the correlation of rs6732655A/T single nucleotide polymorphism to understand the causative association of SCN1A gene with epilepsy drug resistance and inflammatory response.AIM To find the correlation of SCN1A gene rs6732655A/T polymorphism with the drug-resistant epilepsy and inflammatory response.METHODS The study enrolled 100 age and sex-matched patients of both drug-resistant and drug-responsive epilepsy cases.We analysed the rs6732655A/T polymorphism to study its association and causative role in drug-resistant epilepsy cases using restriction fragment length polymorphism technique.The diagnostic performance of interleukin(IL)-1β,IL-6,and high mobility group box 1(HMGB1)protein levels was evaluated in conjunction with genotypic outcome receiver operating characteristic analysis.RESULTS AT and AA genotypes of rs6732655 SCN1A gene polymorphism were associated with higher risk of drug resistance epilepsy.Serum biomarkers IL-6,IL1βand HMGB1 demonstrated diagnostic potential,with cutoff values of 4.63 pg/mL,59.52 pg/mL and 7.99 ng/mL,respectively,offering valuable tools for epilepsy management.Moreover,specific genotypes(AA and AT)were found to be linked to the elevated levels of IL-1βand IL-6 and potentially reflecting increased oxidative stress and neuro-inflammation in drug-resistant cases supporting the previous reported outcome of high inflammatory markers response in drug resistance epilepsy.CONCLUSION SCN1A genotypes AA and AT are linked to higher drug-resistant epilepsy risk.These findings underscore the potential influence of inflammation and genetics on epilepsy treatment resistance. 展开更多
关键词 EPILEPSY Drug resistance scn1A gene Pro-inflammatory cytokines Genetic factors
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SCN4A基因R669H变异的家族性低钾性周期性麻痹1家系分析
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作者 李洁 王乐 +1 位作者 黄雪霜 姜海鸥 《临床神经病学杂志》 CAS 2024年第1期43-45,共3页
目的 探讨一个低钾性周期性麻痹(HOKPP)家系的临床及遗传学特点。方法 回顾性分析1个HOKPP家系的临床资料。结果 先证者表现为周期性瘫痪,发作时四肢无力,血钾明显降低(1~2 mmol/L),先证者的父亲及表哥有相似症状。基因检测发现,先证者... 目的 探讨一个低钾性周期性麻痹(HOKPP)家系的临床及遗传学特点。方法 回顾性分析1个HOKPP家系的临床资料。结果 先证者表现为周期性瘫痪,发作时四肢无力,血钾明显降低(1~2 mmol/L),先证者的父亲及表哥有相似症状。基因检测发现,先证者、父亲、小姑和表哥SCN4A基因存在1个杂合错义变异c.2006G>A(p.R669H),其大姑及叔叔未发现该变异。结论 该家系呈现不规则显性遗传,男性杂合子严重程度、发病频率和起病年龄有所不同,而女性杂合子无临床表型。本研究首次明确在亚洲种族人群中R669H变异导致男性完全外显,而女性可能为携带者。 展开更多
关键词 低钾性周期性麻痹 全外显子组测序 scn4A基因 突变 不完全外显
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基于VMD与AdaBoost-SCN的海缆振动信号识别方法 被引量:1
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作者 尚秋峰 黄达 巩彪 《振动与冲击》 EI CSCD 北大核心 2023年第19期231-239,共9页
海底光缆的在线监测和振动信号识别是保证其正常运行的关键技术。搭建了基于布里渊光时域分析系统,模拟不同工况下的海缆振动信号。针对海缆振动信号信息丰富、信噪比低,使用单一随机配置网络(stochastic configuration network,SCN)模... 海底光缆的在线监测和振动信号识别是保证其正常运行的关键技术。搭建了基于布里渊光时域分析系统,模拟不同工况下的海缆振动信号。针对海缆振动信号信息丰富、信噪比低,使用单一随机配置网络(stochastic configuration network,SCN)模型对信号识别准确率不高的问题,提出了自适应增强(adaptive boosting,AdaBoost)算法优化的随机配置网络(AdaBoost-SCN)识别方法。首先用变分模态分解(variational mode decomposition,VMD)算法分解海缆振动信号,构建特征向量;然后采用AdaBoost-SCN算法对振动信号分类。结果表明,所提方法有着很高的精度,并且具有很强的鲁棒性与泛化能力,提高了布里渊光时域分析系统振动信号识别的有效性。 展开更多
关键词 信号识别 变分模态分解(VMD) 随机配置网络(scn) 自适应增强(AdaBoost)算法
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SCN5A基因突变相关儿童心律失常临床分析
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作者 张海燕 姚如恩 许静 《儿科药学杂志》 CAS 2023年第7期48-51,共4页
目的:探讨SCN5A基因突变与儿童心律失常的关系。方法:回顾分析2018年1月至2020年6月我院诊治的8例心律失常合并SCN5A基因突变患儿的临床资料。结果:8例患儿中男7例、女1例,年龄5.5(2.5~7.0)岁。晕厥发作为主要临床表现,发生率为87.5%(7... 目的:探讨SCN5A基因突变与儿童心律失常的关系。方法:回顾分析2018年1月至2020年6月我院诊治的8例心律失常合并SCN5A基因突变患儿的临床资料。结果:8例患儿中男7例、女1例,年龄5.5(2.5~7.0)岁。晕厥发作为主要临床表现,发生率为87.5%(7/8)。其中1例晕厥发作与窦性静止、房扑有关,6例晕厥发作与室性心动过速发生有关。6例发生室性心动过速的患儿中,结合心电图及基因检查,4例诊断为Brugada综合征(Brs),1例为3型长QT间期综合征(LQT3),1例为Brs合并LQT3。3例患儿合并有左心功能射血分数的明显下降。结论:SCN5A基因突变与儿童恶性心律失常有关,需要引起重视,必要时应尽早行基因组测序予以精准的治疗。 展开更多
关键词 scn5A基因 BRUGADA综合征 长QT间期综合征
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Energy-efficient data transmission with non-ideal circuit power for downlink cellular networks
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作者 杨灼其 周庆 +2 位作者 刘楠 潘志文 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期5-13,共9页
The downlink energy-efficient transmission schedule with non-ideal circuit power over Wreless networks involving a single transmitter and multiple receivers was investigated. According to the special structure of the ... The downlink energy-efficient transmission schedule with non-ideal circuit power over Wreless networks involving a single transmitter and multiple receivers was investigated. According to the special structure of the problem, a novel algorithm called OOSCPMR (the optimal offine scheduling with non-ideal circuit power for multi-receivers) is proposed, and the optimal offine solutions to optimize the energy- efficient transmission policy are found. The packets to be transmitted can be divided into two types where one type of packet is determined to be transmitted using the enrgy- efficient tansmission time, and the other type of packet is determined by the ID moveright algorithm. Finally, an energy-efficient online schedule is developed based on te proposed OOSCPMR algoriAm. Simulation results show that the optima offline transmission schedule provides te lower bound performance for the online tansmission schedule. The proposed optimal offline and online policy is more energy efficient than the existing schemes tat assume ideal circuit power. 展开更多
关键词 energy efficiency transmission schedule multiple receivers non-ideal circuit power
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A Non-linear Non-ideal Model of Simulated Moving Bed Chromatography for Chiral Separations 被引量:8
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作者 卢建刚 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期234-239,共6页
A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of... A non-linear non-ideal model, taking into account non-linear competitive isotherms, axial dispersion, film mass transfer, intraparticle diffusion, and port periodic switching, was developed to simulate the dynamics of simulated moving bed chromatography (SMBC). The model equations were solved by a new efficient numerical technique of orthogonal collocation on finite elements with periodical movement of concentration vector. The simulated SMBC performance is in accordance with the experimental results reported in the literature for separation of l,1'-bi-2-naphthol enantiomers using SMBC. This model is useful for design, operation, optimization and scale-up of non-linear SMBC for chiral separations with significant non-ideal effects, especially for high solute concentration and small intraparticle diffusion coefficient or large chiral stationary phase particle. 展开更多
关键词 simulated moving bed chromatography chiral separation non-linear isotherm non-ideal effect DYNAMICS
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Numerical modelling of non-ideal detonation in ANFO explosives applying Wood-Kirkwood theory coupled with EXPLO5 thermochemical code 被引量:4
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作者 Barbara Stimac Vinko Skrlec +1 位作者 Mario Dobrilovic Muhamed Suceska 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第5期1740-1752,共13页
Ammonium nitrate and fuel oil(ANFO)based explosive is a classic example of non-ideal high explosives.Its detonation is characterized by a strong dependence of detonation parameters on explosive charge diameter,presenc... Ammonium nitrate and fuel oil(ANFO)based explosive is a classic example of non-ideal high explosives.Its detonation is characterized by a strong dependence of detonation parameters on explosive charge diameter,presence and characteristics of confinement,as well as incomplete consumption of explosive at the sonic point.In this work we propose a detonation model based on the Wood-Kirkwood(WK)theory coupled with the thermochemical code EXPLO5 and supplemented with reaction rate models.Our objective is to analyze the validity of the model for highly non-ideal ANFO explosives,with emphasis on effect of reaction rate models.It was found that both single-step and two-step pressure-based models can be calibrated to reproduce experimental detonation velocity-charge radius data of ANFO at radii significantly above the failure radius(i.e.for D/D_(id)>~0.6).Single-step pressure-based model,with the pressure exponent equal to 1.4,proved to be the most accurate,even in the vicinity of the failure radius.The impact of the rate models is most evident on temporal(and spatial)distribution of flow parameters in detonation driving zone,especially when it comes to the conversion and width of detonation driving zone. 展开更多
关键词 ANFO non-ideal detonation Reaction rate model Numerical modelling EXPLO5
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A novel digital control strategy of three-phase shunt active power filter under non-ideal mains voltages 被引量:1
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作者 胡志坤 陈志文 +2 位作者 华长春 王会海 丁家峰 《Journal of Central South University》 SCIE EI CAS 2011年第6期2021-2030,共10页
A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous... A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient. 展开更多
关键词 non-ideal mains voltage deadbeat control fundamental positive sequence active current shunt active power filter
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SCN5A基因突变致家族性多源希浦系综合征一例 被引量:1
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作者 吕顺 焦鸿瑞 +2 位作者 王小艳 庄敏 牛惠萍 《中国循环杂志》 CSCD 北大核心 2023年第5期568-572,共5页
多源希浦系综合征,即MEPPC综合征,是一种心脏钠离子通道病。该综合征是由SCN5A基因突变所致,其临床主要表现为室性心律失常(室性早搏和阵发性室性心动过速)和扩张型心肌病。目前,国内外关于该综合征的报道很少。本文报道一例具有家族性... 多源希浦系综合征,即MEPPC综合征,是一种心脏钠离子通道病。该综合征是由SCN5A基因突变所致,其临床主要表现为室性心律失常(室性早搏和阵发性室性心动过速)和扩张型心肌病。目前,国内外关于该综合征的报道很少。本文报道一例具有家族性发病特征的MEPPC综合征,通过分析该患者临床表现、心电图、超声心动图和基因检测结果,提高临床医师对该综合征的认识,为进一步治疗提供参考。 展开更多
关键词 scn5A基因 多源希浦系综合征 MEPPC综合征 心律失常
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SCN4A基因突变导致的低钾性周期性麻痹2例报道并文献复习
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作者 曹聪慧 曹艳丽 王晓黎 《中国医科大学学报》 CAS 北大核心 2023年第8期761-765,共5页
本文报道2例SCN4A基因突变导致的家族性低钾性周期性麻痹病例的基因及临床特点,全外显子组测序提示2例先证者的SCN4A基因存在杂合性突变,其中1例携带的突变(R672L)尚未见文献及数据库报道。本文进一步对文献中已报道的相关病例进行回顾... 本文报道2例SCN4A基因突变导致的家族性低钾性周期性麻痹病例的基因及临床特点,全外显子组测序提示2例先证者的SCN4A基因存在杂合性突变,其中1例携带的突变(R672L)尚未见文献及数据库报道。本文进一步对文献中已报道的相关病例进行回顾性分析。 展开更多
关键词 周期性麻痹 scn4A基因 全外显子组测序 低钾血症
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Pseudoelastic effect in autoparametric non-ideal vibrating system with SMA spring
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作者 Danuta Sado Marek Pietrzakowski Krzysztof Gajos 《Theoretical & Applied Mechanics Letters》 CAS 2012年第4期69-74,共6页
In this paper a three degrees of freedom autoparametric system with limited power supply is investigated numerically. The system consists of the body, which is hung on a spring and a damper, and two pendulums connecte... In this paper a three degrees of freedom autoparametric system with limited power supply is investigated numerically. The system consists of the body, which is hung on a spring and a damper, and two pendulums connected by shape memory alloy (SMA) spring. Shape memory alloys have ability to change their material properties with temperature. A polynomial constitutive model is assumed to describe the behavior of the SMA spring. The non-ideal source of power adds one degree of freedom, so the system has four degrees of freedom. The equations of motion have been solved numerically and pseudoelastic effects associated with the martensitic phase transformation are studied. It is shown that in this type system one mode of vibrations might excite or damp another mode, and that except different kinds of periodic vibrations there may also appear chaotic vibrations. For the identification of the responses of the system's various techniques, including chaos techniques such as bifurcation diagrams and time histories, power spectral densities, Poincare maps and exponents of Lyapunov may be used. 展开更多
关键词 autoparametric vibrations non-ideal system shape memory alloy CHAOS
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Confinement Effect and Diameter Effect on the Non-ideal Detonation Parameters of Small Charge
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作者 徐新春 焦清介 +1 位作者 金兆鑫 杨贵丽 《Journal of Beijing Institute of Technology》 EI CAS 2010年第4期399-404,共6页
An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation vel... An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation velocity and the semi-empirical relationship of detonation pressure that both change with charge diameter and confinement condition are established.The detonation velocity and pressure of small charges are calculated and experimentally verified,and the detonation velocity deviation is less than 7% while the detonation pressure deviation is less than 9%. 展开更多
关键词 explosion mechanics non-ideal detonation small charge diameter effect the nozzle theory
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厦门地区三例Brugada综合征患者SCN5A基因突变分析
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作者 葛高顺 林玲 +1 位作者 倪二茹 谢华斌 《现代检验医学杂志》 CAS 2023年第2期81-85,101,共6页
目的探讨厦门地区3例Brugada综合征患者SCN5A基因突变情况。方法选取2011年1月~2022年6月到厦门大学附属心血管病医院就诊的3例Brugada综合征患者作为观察组,同期20例健康体检者作为对照组,收集两组人群的常规生化与心肌标志物检测结果... 目的探讨厦门地区3例Brugada综合征患者SCN5A基因突变情况。方法选取2011年1月~2022年6月到厦门大学附属心血管病医院就诊的3例Brugada综合征患者作为观察组,同期20例健康体检者作为对照组,收集两组人群的常规生化与心肌标志物检测结果。采集观察组全血后提取基因组DNA,应用高通量测序平台对Brugada综合征相关基因的目标区域测序,再预测蛋白质三维结构,比较国内已报道的Brugada综合征相关新发疑似致病SCN5A基因突变。结果观察组与对照组的常规生化与心肌标志物检测结果均无明显差异,目标区域捕获测序结果显示有2位受检者都携带SCN5A c·219delA移码突变,该突变导致74位的谷氨酸变成了丝氨酸,并产生新的阅读框架,终止于第74号密码子下游23位密码子处,产生一个缩短并变异的RNA以及蛋白。另一位受检者携带SCN5A c·584G>A无义突变,该突变会导致编码蛋白序列提前终止,产生一个截短的蛋白,可能会对蛋白质的结构和功能产生较大影响。这两个点突变都未有文献报道,在各大公共数据库中均没有被检索到,根据美国医学遗传学与基因组学协会(ACMG)评估指南,定义该位点为疑似致病突变的变异。结论SCN5A c·219delA和SCN5A c·584G>A点突变是Brugada综合征的致病原因。 展开更多
关键词 BRUGADA综合征 scn5A 厦门
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Investigation of Shock Waves in Non-Ideal Gas under the Action of Magnetic Field
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作者 Kanti Pandey Praveen Prakash Pathak 《Advances in Pure Mathematics》 2017年第10期583-596,共14页
In present paper, certain aspect of shock wave in non-ideal gas, when magnetic field is orthogonal to the trajectories of the gas particles and electrical conductivity is taken to be infinite, is investigated. Conside... In present paper, certain aspect of shock wave in non-ideal gas, when magnetic field is orthogonal to the trajectories of the gas particles and electrical conductivity is taken to be infinite, is investigated. Considering one-dimensional unsteady non-planer motion, basic equations, its general solution and formation of shock-wave, conservation laws and jumps conditions, variation of area of non-uniform cross section and analytical solution of strong non planer shock is obtained. 展开更多
关键词 SHOCK-WAVES non-ideal GASES Magnetic Field
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