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Evaluating Pharmacological and Rehabilitation Strategies for Effective Management of Bipolar Disorder: A Comprehensive Clinical Study
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作者 Rocco de Filippis Abdullah Al Foysal 《Advances in Bioscience and Biotechnology》 CAS 2024年第7期406-431,共26页
Bipolar disorder presents significant challenges in clinical management, characterized by recurrent episodes of depression and mania often accompanied by impairment in functioning. This study investigates the efficacy... Bipolar disorder presents significant challenges in clinical management, characterized by recurrent episodes of depression and mania often accompanied by impairment in functioning. This study investigates the efficacy of pharmacological interventions and rehabilitation strategies to improve patient outcomes and quality of life. Utilizing a randomized controlled trial with multiple treatment arms, participants will receive pharmacotherapy, polypharmacotherapy, rehabilitation interventions, or combination treatments. Outcome measures will be assessed using standardized scales, including the Hamilton Depression Scale, Yale-Brown Obsessive Compulsive Scale (Y-BOCS), and Mania Scale. Preliminary data suggest improvements in symptom severity and functional outcomes with combination treatments. This research aims to inform clinical practice, guide treatment decisions, and ultimately enhance the quality of care for individuals living with bipolar disorder. Findings will be disseminated through peer-reviewed journals and scientific conferences to advance knowledge in this field. 展开更多
关键词 bipolar disorder (Bd) Pharmacotherapy (PT) Rehabilitation Interventions (RI) Hamilton depression Scale (HAM-d) Yale-Brown Obsessive Compulsive Scale (Y-BOCS) Mania Scale (MS) Machine learning (ML) and Artificial Intelligence (AI).
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Ionizing radiation effect on 10-bit bipolar A/D converter
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作者 CHEN Rui LU Wu +6 位作者 REN Diyuan ZHENG Yuzhan WANG Yiyuan FEI Wuxiong LI Maoshun LAN Bo CUI Jiangwei 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第3期152-156,共5页
In this article,radiation effects and annealing characteristics of a bipolar analog-to-digital converter(ADC) are investigated in different biases and dose rates.The results show that ADC is sensitive to both the bias... In this article,radiation effects and annealing characteristics of a bipolar analog-to-digital converter(ADC) are investigated in different biases and dose rates.The results show that ADC is sensitive to both the bias and dose rate. Under high-dose-rate irradiation,the ADC functions well,while under low-dose-rate irradiation,the parameters of ADC change obviously at low dose level,and the damage is significant at zero bias.Combining the fringing field with the space charge model,the underlying mechanism for this response is discussed. 展开更多
关键词 数字转换器 辐射效应 双极性 电离辐射 低剂量率 AdC 退火特性 参数变化
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A 12bit 300MHz Current-Steering CMOS D/A Converter 被引量:1
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作者 倪卫宁 耿学阳 石寅 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1129-1134,共6页
The proposed DAC consists of a unit current-cell matrix for 8MSBs and a binary-weighted array for 4LSBs,trading-off between the precision,speed,and size of the chip.In order to ensure the linearity of the DAC,a double... The proposed DAC consists of a unit current-cell matrix for 8MSBs and a binary-weighted array for 4LSBs,trading-off between the precision,speed,and size of the chip.In order to ensure the linearity of the DAC,a double Centro symmetric current matrix is designed by the Q2 random walk strategy.To achieve better dynamic performance,a latch is added in front of the current switch to change the input signal,such as its optimal cross-point and voltage level.For a 12bit resolution,the converter reaches an update rate of 300MHz. 展开更多
关键词 d/a converter current-steering CMOS mixed integrated circuit cross-point Q2 random walk
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A 16 bit Stereo Audio ΣΔ A/D Converter
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作者 陈雷 赵元富 +3 位作者 高德远 文武 王宗民 朱小飞 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第7期1183-1188,共6页
A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a hig... A 16 bit stereo audio novel stability fifth-order ∑△ A/D converter that consists of switched capacitor ∑△ modulators, a decimation filter, and a bandgap circuit is proposed. A method for the stabilization of a high order single stage ∑△ modulator is also proposed. A new multistage comb filter is used for the front end decimation filter. The ∑△ A/D converter achieves a peak SNR of 96dB and a dynamic range of 96dB. The ADC was implemented in 0. 5μm 5V CMOS technology. The chip die area occupies only 4. 1mm × 2.4mm and dissipates 90mW. 展开更多
关键词 ∑△ A/d converter switched capacitor STABILITY decimation filter bandgap circuits
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基于D-分割法的直流变换器遗传自抗扰控制器设计
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作者 周雪松 王鑫 +3 位作者 马幼捷 王博 赵明 问虎龙 《太阳能学报》 EI CAS CSCD 北大核心 2024年第9期378-385,共8页
针对光伏发电系统中DC-DC变换器由于负载和工作环境条件变化等扰动引起的输出波动问题,提出一种基于D-分割法的直流变换器遗传自抗扰控制器(ADRC)设计方法。该方法适用于设计光伏发电领域中的双向DC-DC变换器,采用D-分割法获得满足闭环... 针对光伏发电系统中DC-DC变换器由于负载和工作环境条件变化等扰动引起的输出波动问题,提出一种基于D-分割法的直流变换器遗传自抗扰控制器(ADRC)设计方法。该方法适用于设计光伏发电领域中的双向DC-DC变换器,采用D-分割法获得满足闭环系统鲁棒稳定的ADRC控制器参数范围;利用具有全局寻优能力的遗传算法,按综合性能指标在该范围内进行参数寻优。实验结果表明,所提基于D-分割法的直流变换器遗传自抗扰控制器设计方法能有效抑制微网母线侧的电压波动和负载突变,提高控制器的鲁棒性,增强光伏发电系统的动态响应性能和抗干扰能力。 展开更多
关键词 光伏发电 dC-dC变换器 遗传算法 自抗扰控制 d-分割法
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一种双极性输出端口电压自平衡隔离型DC/DC变换器
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作者 邾玢鑫 周丽娟 +1 位作者 杨浴金 王凯宏 《中国电机工程学报》 EI CSCD 北大核心 2024年第14期5702-5713,I0022,共13页
隔离型DC/DC变换器通过多绕组变压器可方便地实现多路或双极性输出,但因交叉调整率问题,在负载不平衡时输出各端口电压存在较大偏差。针对该问题,该文基于反激变换器推导出一种双极性端口电压自平衡隔离型DC/DC变换器。所提方案结构简... 隔离型DC/DC变换器通过多绕组变压器可方便地实现多路或双极性输出,但因交叉调整率问题,在负载不平衡时输出各端口电压存在较大偏差。针对该问题,该文基于反激变换器推导出一种双极性端口电压自平衡隔离型DC/DC变换器。所提方案结构简单、成本低,在不改变传统反激变换器驱动及控制电路设计的情况下能够较好的实现端口电压自平衡,且所提变换器结构具有可拓展性。文中首先详细阐述了所提变换器拓扑的推演过程,然后对变换器的工作原理、性能特点以及电压自平衡机理进行分析。最后,搭建了一台150 W的实验样机,验证了所提变换器理论分析的正确性和有效性。 展开更多
关键词 双极性 反激变换器 交叉调整率 电压自平衡
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一种高速A/D转换器时域重构技术研究
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作者 崔庆林 杨松 《微电子学》 CAS 北大核心 2024年第2期317-322,共6页
A/D转换器在航空航天系统中的重要元器件,随着器件转换时钟频率不断提高而其工作环境不断恶化,如何准确测试其时间参数对于全面评价A/D转换器性能特别重要。目前对于高速A/D转换器时间参数测试,主流方法是通过示波器直接测试其输出,该... A/D转换器在航空航天系统中的重要元器件,随着器件转换时钟频率不断提高而其工作环境不断恶化,如何准确测试其时间参数对于全面评价A/D转换器性能特别重要。目前对于高速A/D转换器时间参数测试,主流方法是通过示波器直接测试其输出,该方法对于示波器采样速度要求比较高。文章提出一种高速A/D转换器时域重构技术,可以通过计算机数字信号处理方法来实现高速A/D转换器时间参数测试,同时避免对示波器采样速度的依赖。同时,在研究高速A/D转换器时域重构技术方法及其应用的基础上,通过了相关试验验证。 展开更多
关键词 高速A/d转换器 时域重构 瞬态响应 过压恢复 缺陷分析 单粒子闭锁和翻转
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Numeric Simulation of Single Passage Ternary Turbulence Model in Hydraulic Torque Converter 被引量:5
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作者 闫清东 魏巍 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期172-175,共4页
Based on the renormalization group theory, a hydraulic torque converter 3 D turbulent single flow passage model is constructed and boundary condition is determined for analyzing the influence of the fluid field chara... Based on the renormalization group theory, a hydraulic torque converter 3 D turbulent single flow passage model is constructed and boundary condition is determined for analyzing the influence of the fluid field characteristic and parameters on the macroscopic model. Numerical simulation of the single fluid path is processed by computational fluid dynamics and the calculated results approach to experimental data well, and especially in low transmission ratio the torque and head results are more close to experimental data than the calculated results of beam theory. This shows that the appropriate ternary analysis method and reasonable assumption of boundary condition may analyze the flow field more precisely and predict the performance of torque converter more accurately. 展开更多
关键词 hydraulic torque converter 3 d fluid field computational fluid dynamics
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A 10bit 2GHz CMOS D/A Converter for High-Speed System Applications
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作者 袁凌 倪卫宁 石寅 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第10期1540-1545,共6页
This paper presents a 2GS/s 10bit CMOS digital-to-analog converter (DAC) that consists of two unit current-cell matrixes for 6MSBs and 4LSBs, respectively, trading off between the precision and size of the chip. Cur... This paper presents a 2GS/s 10bit CMOS digital-to-analog converter (DAC) that consists of two unit current-cell matrixes for 6MSBs and 4LSBs, respectively, trading off between the precision and size of the chip. Current mode logic (CML) is used to ensure high speed,and a double centro-symmetric current matrix is designed by the Q^2 random walk strategy in order to ensure the linearity of the DAC. The DAC occupies 2.2mm × 2.2mm of die area and consumes 790mW with a single 3.3V power supply. 展开更多
关键词 d/a converter current steering CMOS mixed integrated circuit Q^2 random walk
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基于DAC阵列的光交叉芯片控制驱动系统
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作者 欧阳傲奇 吕昕雨 +5 位作者 许馨如 曾国宴 尹悦鑫 李丰军 张大明 郜峰利 《吉林大学学报(信息科学版)》 CAS 2024年第2期232-241,共10页
为标定光交叉芯片驱动电压,控制光交叉芯片实现光路由功能,提出并搭建了基于多通道DAC(Digital to Analog Converter)阵列的控制驱动电路系统。系统主要由控制系统模块、多路驱动电路模块及上位机控制模块构成。控制电路和驱动电路具有... 为标定光交叉芯片驱动电压,控制光交叉芯片实现光路由功能,提出并搭建了基于多通道DAC(Digital to Analog Converter)阵列的控制驱动电路系统。系统主要由控制系统模块、多路驱动电路模块及上位机控制模块构成。控制电路和驱动电路具有调校简单、可双极性输出、输出路数多、加电精确度较高的特点,解决了当前驱动电路工作繁琐、加电极性单一、加电路数少、精度差的问题。上位机控制模块除了可控制驱动电路施加控制电压外,还可接收来自数据采集装置采集到的光功率信号作为控制驱动系统的反馈信号。通过分析控制电压与光功率之间的关系,可得到最佳的光交叉芯片控制驱动电压。系统测试实验结果表明,该系统能提供高精确度的双极性驱动电压,有效地对光交叉芯片进行驱动。可在较短的时间内标定出光开关的控制电压,完全可以满足有源光交叉芯片控制中对驱动电压的需求。该系统在光交叉芯片控制方面具有一定的应用价值。 展开更多
关键词 光交叉芯片 dAC阵列 双极性电压 电路系统 反馈控制
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A 128×128 SPAD LiDAR sensor with column-parallel 25 ps resolution TA-ADCs 被引量:1
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作者 Na Tian Zhe Wang +6 位作者 Kai Ma Xu Yang Nan Qi Jian Liu Nanjian Wu Runjiang Dou Liyuan Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期34-40,共7页
This paper presents a design of single photon avalanche diode(SPAD)light detection and ranging(LiDAR)sensor with 128×128 pixels and 128 column-parallel time-to-analog-merged-analog-to-digital converts(TA-ADCs).Un... This paper presents a design of single photon avalanche diode(SPAD)light detection and ranging(LiDAR)sensor with 128×128 pixels and 128 column-parallel time-to-analog-merged-analog-to-digital converts(TA-ADCs).Unlike the conventional TAC-based SPAD LiDAR sensor,in which the TAC and ADC are separately implemented,we propose to merge the TAC and ADC by sharing their capacitors,thus avoiding the analog readout noise of TAC’s output buffer,improving the conversion rate,and reducing chip area.The reverse start-stop logic is employed to reduce the power of the TA-ADC.Fabricated in a 180 nm CMOS process,our prototype sensor exhibits a timing resolution of 25 ps,a DNL of+0.30/−0.77 LSB,an INL of+1.41/−2.20 LSB,and a total power consumption of 190 mW.A flash LiDAR system based on this sensor demonstrates the function of 2D/3D imaging with 128×128 resolution,25 kHz inter-frame rate,and sub-centimeter ranging precision. 展开更多
关键词 3d imaging CMOS imagers direct time-of-flight(dTOF) time-to-analog converter(TAC)
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Performance Optimization of Torque Converters Based on Modified 1D Flow Model 被引量:3
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作者 吴光强 王立军 《Journal of Donghua University(English Edition)》 EI CAS 2012年第5期380-384,共5页
A methodology for performance optimization of torque converters is put forward based on the one-dimensional (1D) flow model. It is found that the inaccuracy of 1D flow model for predicting hydraulic performance at the... A methodology for performance optimization of torque converters is put forward based on the one-dimensional (1D) flow model. It is found that the inaccuracy of 1D flow model for predicting hydraulic performance at the low speed ratio is mainly caused by the separation phenomenon at the stator cascade which is induced by large flow impinging at the pressure side of the stator blades. A semi-empirical separation model is presented and incorporated to the original 1D flow model. It is illustrated that the improved model is able to predict the circumferential velocity components accurately, which can be applied to performance optimization. Then, the Pareto front is obtained by using the genetic algorithm (GA) in order to inspect the coupled relationship among stalling impeller torque capacity, stalling torque ratio and efficiency. The efficiency is maximized on the premise that a target stalling impeller torque capacity and torque ratio are achieved. Finally, the optimized result is verified by the computational fluid dynamics(CFD) simulation, which indicates that the maximal efficiency is increased by 0.96%. 展开更多
关键词 multi-objective optimization torque converter separation flow Pareto front one-dimensional 1 d flow model
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Numerical simulation of the flow field of a flat torque converter 被引量:6
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作者 闫清东 刘城 魏巍 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期309-314,共6页
A flexible flat torque converter was proposed to fulfill the requirement of miniaturization and power density maximization for automobiles.Constructed by two arcs joined by lines,the torus was designed directly from d... A flexible flat torque converter was proposed to fulfill the requirement of miniaturization and power density maximization for automobiles.Constructed by two arcs joined by lines,the torus was designed directly from design path.The influence of flatness on the performance of the torque converter was evaluated.The software CFX and standard k-ε model were adopted to simulate the internal flow fields of the torque converter under different flatness ratios.The results indicated that the performance of the torque converter got worse as the flatness declined,but the capacity of pump increased.The efficiency and the torque ratio dropped slightly as the flatness ratio decreased.So the torque converter could be squashed appropriately to get high power density without too much efficiency sacrifice.But when the flatness ratio was below 0.2,there was a significant drop in the efficiency. 展开更多
关键词 torque converter 3d flow simulation flatness ratio efficiency high power density
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Analytical Modelling and Experiment of Novel Rotary Electro-Mechanical Converter with Negative Feedback Mechanism for 2D Valve 被引量:1
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作者 Bin Meng Mingzhu Dai +3 位作者 Chenhang Zhu Chenchen Zhang Chuan Ding Jian Ruan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第5期162-182,共21页
The manufacturing of spiral groove structure of two-dimensional valve(2D valve)feedback mechanism has shortcomings of both high cost and time-consuming.This paper presents a novel configuration of rotary electro-mecha... The manufacturing of spiral groove structure of two-dimensional valve(2D valve)feedback mechanism has shortcomings of both high cost and time-consuming.This paper presents a novel configuration of rotary electro-mechanical converter with negative feedback mechanism(REMC-NFM)in order to replace the feedback mechanism of spiral groove and thus reduce cost of valve manufacturing.In order to rapidly and quantitative evaluate the driving and feedback performance of the REMC-NFM,an analytical model taking leakage flux,edge effect and permeability nonlinearity into account is formulated based on the equivalent magnetic circuit approach.Then the model is properly simplified in order to obtain the optimal pitch angle.FEM simulation is used to study the influence of crucial parameters on the performance of REMC-NFM.A prototype of REMC-NFM is designed and machined,and an exclusive experimental platform is built.The torque-angle characteristics,torque-displacement characteristics,and magnetic flux density in the working air gap with different excitation currents are measured.The experimental results are in good agreement with the analytical and FEM simulated results,which verifies the correctness of the analytical model.For torque-angle characteristics,the overall torque increases with both current and rotation angle,which reaches about 0.48 N·m with 1.5 A and 1.5°.While for torque-displacement characteristics,the overall torque increases with current yet decrease with armature displacement due to the negative feedback mechanism,which is about 0.16 N·m with 1.5 A and 0.8 mm.Besides,experimental results of conventional torque motor are compared with counterparts of REMC-NFM in order to validate the simplified model.The research indicates that the REMC-NFM can be potentially used as the electro-mechanical converter for 2D valves in civil servo areas. 展开更多
关键词 Electro-mechanical converter Magnetic circuit topology Analytical modeling 2d valve
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一种14位80 MS/s流水线型A/D转换器设计
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作者 郭小辉 黄星辰 +4 位作者 徐福彬 洪炜强 赵雨农 洪琪 许耀华 《微电子学与计算机》 2024年第10期89-94,共6页
基于SMIC 0.18μm CMOS工艺,设计了一种14位80 MS/s的流水线型A/D转换器(ADC)。为了降低ADC整体功耗,首级电路采用2.5 bit无采样保持(SHA-less)结构。进一步,基于套筒式共源-共栅结构提出了一种改进型运放,通过复制尾电流反馈技术和增... 基于SMIC 0.18μm CMOS工艺,设计了一种14位80 MS/s的流水线型A/D转换器(ADC)。为了降低ADC整体功耗,首级电路采用2.5 bit无采样保持(SHA-less)结构。进一步,基于套筒式共源-共栅结构提出了一种改进型运放,通过复制尾电流反馈技术和增益提高技术的应用提升了运放的速度和增益,且功耗较低。比较器仅采用动态锁存器以减小级间延迟。还采用了栅压自举开关降低开关导通电阻,提高采样网络带宽和线性度。芯片测试结果表明,在1.8 V电源电压、采样频率为80 MHz的条件下,输入信号频率分别为10 MHz和70 MHz时,ADC的动态参数性能相差不大。其中,输入信号频率为70 MHz时,信噪失真比(SNDR)为72.2 dB,无杂散动态范围(SFDR)为85.82 dB,有效位数(ENOB)为11.7 bit,品质因数(FoM)为0.38 pJ/(conv·step)。 展开更多
关键词 流水线型A/d转换器 无采样保持 复制尾电流反馈技术 动态锁存器
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伴有焦虑症状双相抑郁患者认知功能损害与GRIN2B基因启动子区DNA甲基化相关性研究
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作者 余浩 王丞基 +1 位作者 吴瑶 邹韶红 《中国神经精神疾病杂志》 CAS CSCD 北大核心 2024年第5期274-280,共7页
目的探索伴有焦虑症状双相抑郁患者认知功能与N-甲基-D-天冬氨酸受体2B亚基(glutamate iono-tropic receptor NMDA type subunit 2B,GRIN2B)基因启动子区各CpG位点甲基化水平的相关性。方法根据汉密尔顿焦虑量表(14-item Hamilton anxie... 目的探索伴有焦虑症状双相抑郁患者认知功能与N-甲基-D-天冬氨酸受体2B亚基(glutamate iono-tropic receptor NMDA type subunit 2B,GRIN2B)基因启动子区各CpG位点甲基化水平的相关性。方法根据汉密尔顿焦虑量表(14-item Hamilton anxiety rating scale,HAMA)评分将31例双相抑郁患者分为焦虑组15例和非焦虑组16例,同期选取16名健康对照。采用蒙特利尔认知评估量表(Montreal cognitive assessment,MoCA)、数值广度测验(digital span test,DST)、连线测试A部分(trail making test A,TMT-A)、斯特鲁普色词测验(Stroop color and word test,SCWT)评估3组总体认知功能、注意力及执行控制、信息处理速度、执行功能等认知功能维度,采用Massarray质谱法检测所有受试者外周血GRIN2B基因启动子区各CpG位点的DNA甲基化水平。结果3组GRIN2B基因启动子区DNA甲基化水平差异性位点为CpG3、CpG5、CpG7、CpG10、CpG12(P<0.05),其中,焦虑组CpG12甲基化水平低于非焦虑组(36.23%±16.41%vs.50.20%±19.79%,P<0.05)。偏相关分析显示,焦虑组患者中较差的命名能力与GRIN2B基因CpG4低甲基化水平相关(r=0.670,P=0.034),较差的执行功能与CpG6低甲基化水平相关(r=0.926,P<0.001),较差的注意力与GRIN2B基因CpG8高甲基化水平相关(r=-0.810,P=0.025),较差的言语记忆与CpG9高甲基化水平相关(r=-0.810,P<0.001),较差的抽象能力与CpG10高甲基化水平相关(r=-0.756,P=0.011)。结论GRIN2B基因启动子区DNA甲基化水平与伴有焦虑症状双相抑郁患者认知功能损害可能有关联,与双相抑郁患者焦虑症状的产生也可能有关联。 展开更多
关键词 dNA甲基化 双相障碍 抑郁发作 认知功能 焦虑症状 N-甲基-d-天冬氨酸受体2B亚基
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血清GSDMD、ACE2在小儿川崎病中的表达水平及临床意义研究
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作者 范泽卫 李荟 李竹青 《国际检验医学杂志》 CAS 2024年第4期447-451,456,共6页
目的 探索血清焦孔素蛋白D(GSDMD)、血管紧张素转化酶2(ACE2)在小儿川崎病(KD)患儿中的表达水平及临床意义。方法 收集2020年1月至2022年1月该院诊治的90例KD患儿为KD组,根据KD患儿是否发生冠状动脉损伤(CAL),将KD组分为CAL组(32例)和非... 目的 探索血清焦孔素蛋白D(GSDMD)、血管紧张素转化酶2(ACE2)在小儿川崎病(KD)患儿中的表达水平及临床意义。方法 收集2020年1月至2022年1月该院诊治的90例KD患儿为KD组,根据KD患儿是否发生冠状动脉损伤(CAL),将KD组分为CAL组(32例)和非CAL组(58例),选取同期因急性呼吸道感染发热住该院的患儿50例为发热对照组,另选取同期该院儿外科行择期手术的腹股沟斜疝患儿50例为对照组。采用酶联免疫吸附试验检测血清GSDMD、ACE2水平。Pearson相关分析血清GSDMD、ACE2与临床指标的相关性。多因素Logisitic回归分析KD患者发生CAL的影响因素。受试者工作特征(ROC)曲线分析血清GSDMD、ACE2对KD患儿发生CAL的诊断价值。结果 KD组血清GSDMD、ACE2水平高于发热对照组和对照组,差异有统计学意义(均P<0.05)。相比于非CAL组,CAL组KD患儿发热持续时间、丙种球蛋白治疗时间、红细胞沉降率、血小板计数、C反应蛋白、GSDMD、ACE2水平均明显较高,而血钠、白蛋白明显较低,差异有统计学意义(均P<0.05)。Pearson相关分析结果,KD组患儿血清GSDMD、ACE2水平与发热持续时间、丙种球蛋白治疗时间、红细胞沉降率、血小板计数、C反应蛋白呈正相关(均P<0.05),与血钠、白蛋白呈负相关(均P<0.05)。多因素Logistic回归分析结果显示,血清GSDMD、ACE2升高是影响KD患儿发生CAL的独立危险因素。ROC曲线分析结果显示,血清GSDMD、ACE2两项联合检测KD患儿发生CAL的曲线下面积(AUC)及其95%CI为0.918(0.868~0.949),明显大于血清GSDMD、ACE2单项检测的AUC及其95%CI[依次为0.838(0.789~0.887)、0.865(0.811~0.912)],差异有统计学意义(Z=5.116、4.217,均P<0.05)。结论 血清GSDMD、ACE2两项联合检测对于KD患儿发生CAL具有较高的诊断价值。 展开更多
关键词 川崎病 焦孔素蛋白d 血管紧张素转化酶2 冠状动脉损伤
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双U/f下垂控制下双极MMC-HVDC系统交流阻抗建模及稳定性分析
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作者 李鹏坤 王跃 +3 位作者 冯伯乐 薛英林 刘熠 李润田 《电网技术》 EI CSCD 北大核心 2024年第3期1214-1223,共10页
基于模块化多电平换流器的高压柔性直流输电系统(modular multilevel converter-based high voltage direct current,MMC-HVDC)常采用双极接线方式以提高系统功率输送能力和可靠性。然而目前对于风电场经柔直外送系统的稳定性研究集中... 基于模块化多电平换流器的高压柔性直流输电系统(modular multilevel converter-based high voltage direct current,MMC-HVDC)常采用双极接线方式以提高系统功率输送能力和可靠性。然而目前对于风电场经柔直外送系统的稳定性研究集中于单极接线方式,孤岛直驱风电场与采用不同双极协调控制的双极MMC-HVDC互联系统小信号稳定性问题还有待进一步探究。该文首先考虑频率耦合特性、参考系初相位和直流侧耦合特性的影响,分别建立了采用双U/f下垂控制和定U/f-P/Q控制的双极MMC-HVDC系统交流侧等效SISO阻抗模型,并详细分析了金属回线阻抗和双极间功率均分度对交流阻抗特性的影响。接着对比研究了两种协调控制中共有控制环路和特有控制环路对交流侧负电阻特性及互联系统稳定性的影响规律。最后,孤岛直驱风电场经两种双极协调控制下双极MMC-HVDC外送系统Matlab/Simulink时域仿真结果和硬件在环半实物实时仿真实验结果验证了所提出的小信号阻抗模型的精确性和稳定性分析结论的有效性。 展开更多
关键词 模块化多电平换流器 孤岛直驱风电场 双极接线 双U/f下垂控制 定U/f-P/Q控制 阻抗建模 稳定性分析
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分网接入方式下LCC-HVDC系统运动方程模型及交互振荡模式的阻尼特征(二):交互振荡模式研究
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作者 张加卿 郭春义 杨硕 《中国电机工程学报》 EI CSCD 北大核心 2024年第5期1688-1700,I0002,共14页
为研究分网接入方式下电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)系统的交互振荡模式及阻尼特征,基于系统的状态空间模型及系列文章(一)建立的运动方程模型,提取了表征逆变侧... 为研究分网接入方式下电网换相换流器高压直流输电(line commutated converter based high voltage direct current,LCC-HVDC)系统的交互振荡模式及阻尼特征,基于系统的状态空间模型及系列文章(一)建立的运动方程模型,提取了表征逆变侧电气与控制环节强耦合特性的多个弱阻尼交互振荡模式,研究了不同短路比工况下交互振荡模式的变化特征。在此基础上,通过复转矩系数法量化评估了整流侧/逆变侧内部自稳性路径及双极交互作用致稳性路径对主导交互振荡模式阻尼特性的贡献度。结果表明:1)不同短路比工况下交互振荡模式的阻尼比会进行重新分配;2)当逆变侧正负极短路比相差较大时,双极交互作用较弱,正负极系统的稳定性由2个交互振荡模式各自主导,且稳定性特征有所差异;3)当逆变侧正负极短路比相近时,双极间动态交互加强,交互振荡模式会同时主导参与系统两极的稳定性,正负极稳定性特征相似。 展开更多
关键词 电网换相换流器高压直流输电(LCC-HVdC) 分网接入 交互振荡模式 阻尼特征 双极交互作用
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The Design of A/D Converter Circuit Adopting the Technology of PWM
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作者 Chen Ping Li Jing Zhao MingBo 《微计算机信息》 北大核心 2007年第29期272-274,共3页
This text has expounded the working principle of realizing A/D conversion that utilizes the timer within MCU and combinesthe technology of PWM. The design of hardware circuit, improved gradual approached trial arithme... This text has expounded the working principle of realizing A/D conversion that utilizes the timer within MCU and combinesthe technology of PWM. The design of hardware circuit, improved gradual approached trial arithmetic and relevant program design arediscussed in detail. And it has analyzed the resolution of A/D converter based on the technology of PWM, etc. 展开更多
关键词 PWM A/d 转换分辨率 改进逐次逼近试探算法 比较器 电路设计
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