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Synchronous PWM Modulation to Eliminate Circulating Power in Bidirectional Dual-active-bridge Converter
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作者 Gengning Ying Jun Zeng +2 位作者 Ningrui Yang Junfeng Liu Zhixing Yan 《CSEE Journal of Power and Energy Systems》 2026年第1期294-305,共12页
To solve the problem of circulating power of dual active bridge(DAB)DC-DC converter over a wide voltage conversion ratio,this paper proposes a novel synchronous PWM(S-PWM)modulation.Existence of circulating power incr... To solve the problem of circulating power of dual active bridge(DAB)DC-DC converter over a wide voltage conversion ratio,this paper proposes a novel synchronous PWM(S-PWM)modulation.Existence of circulating power increases current stress of devices and decreases efficiency,especially under light load conditions.Several modulation methods have been proposed to overcome the problem.They can reduce or eliminate either input or output side circulating power.In contrast,S-PWM not only eliminates both sides circulating power and reduces current stress,but also achieves zero-current-switching(ZCS)turn-on for all switches and ZCS turn-off for most across the full power range.No auxiliary or snubber circuits are increased.In addition,the control can be simplified so the transmitted power is related to only one variable.The S-PWM has four cases under different gain and power conditions.The detailed operation principle and modes of DAB under S-PWM are analyzed in the paper.In addition,four modulations in literature are discussed,and corresponding comparative analyses with S-PWM are given.Finally,a laboratory prototype is built to verify advantages and effectiveness of the proposed modulation. 展开更多
关键词 Bidirectional converter circulating power dC-dC converter dual active bridge(dAB) soft switching
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A Coordinated Multi-Loop Control Strategy for Fault Ride-Through in Grid-Forming Converters
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作者 Zhuang Liu Mingwei Ren +1 位作者 Kai Shi Peifeng Xu 《Energy Engineering》 2026年第1期115-135,共21页
Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)... Grid-Forming(GFM)converters are prone to fault-induced overcurrent and power angle instability during grid fault-induced voltage sags.To address this,this paper develops a multi-loop coordinated fault ridethrough(FRT)control strategy based on a power outer loop and voltage-current inner loops,aiming to enhance the stability and current-limiting capability of GFM converters during grid fault conditions.During voltage sags,the GFM converter’s voltage source behavior is maintained by dynamically adjusting the reactive power reference to provide voltage support,thereby effectively suppressing the steady-state component of the fault current.To address the active power imbalance induced by voltage sags,a dynamic active power reference correction method based on apparent power is designed to mitigate power angle oscillations and limit transient current.Moreover,an adaptive virtual impedance loop is implemented to enhance dynamic transient current-limiting performance during the fault initiation phase.This approach improves the responsiveness of the inner loop and ensures safe system operation under various fault severities.Under asymmetric fault conditions,a negative-sequence reactive current compensation strategy is incorporated to further suppress negative-sequence voltage and improve voltage symmetry.The proposed control scheme enables coordinated operation of multiple control objectives,including voltage support,current suppression,and power angle stability,across different fault scenarios.Finally,MATLAB/Simulink simulation results validate the effectiveness of the proposed strategy,showcasing its superior performance in current limiting and power angle stability,thereby significantly enhancing the system’s fault ride-through capability. 展开更多
关键词 Grid-forming converter multi-loop coordination negative-sequence control fault ride-through
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Impacts of Reactive Power Control Dynamics on Transient Stability of Grid-forming Converters Considering Current Saturation:Analysis and Enhancement
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作者 Jinming Xu Hanxu Diao +3 位作者 Zihan Ling Jiarong Kan Yunhu Luo Shaojun Xie 《CSEE Journal of Power and Energy Systems》 2026年第1期56-70,共15页
The transient synchronization stability of grid-forming converters(GFMCs)is significantly challenged under grid voltage sags.Continuous efforts have been devoted to analyzing the GFMC transient stability,with limited ... The transient synchronization stability of grid-forming converters(GFMCs)is significantly challenged under grid voltage sags.Continuous efforts have been devoted to analyzing the GFMC transient stability,with limited attention paid to the impacts of control loop dynamics.However,the complex control dynamics,especially the interactions between the active/reactive power control loops and the current saturation process(CSP),are crucial for accurately describing the transient behavior and evaluating the stability.Thus,in this study,a new large-signal GFMC model is established,considering the reactive power control(RPC)with different kinds of controllers and the CSP simultaneously.It is revealed that GFMC does not switch to the current-limited mode immediately,and the dynamics of RPC further affect the transient behavior before the current limiting significantly.Hence,the complex control dynamics can alter the mode switching point of current saturation,thereby increasing the risk of loss of synchronization(LOS).Based on the above findings,comprehensive comparisons of typical RPC controllers are presented to facilitate practical engineering applications.A unified stability enhancement method is proposed for solving the problem of LOS.Finally,experiments validate the correctness of the analysis and the effectiveness of the proposed control strategy. 展开更多
关键词 Current limit grid-forming converter reactive power control transient stability
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Synthesis of Dynamic Virtual Impedance for Grid-forming Converters to Improve Self-stability and Stabilizing Ability
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作者 Hangyu Chen Verena Häberle +3 位作者 Ying Yang Kehao Zhuang Huanhai Xin Linbin Huang 《CSEE Journal of Power and Energy Systems》 2026年第1期44-55,共12页
In the future power-electronics-dominated power systems,grid-forming(GFM)converters have been regarded as important devices to actively establish frequency and voltage,so as to provide essential grid support.However,d... In the future power-electronics-dominated power systems,grid-forming(GFM)converters have been regarded as important devices to actively establish frequency and voltage,so as to provide essential grid support.However,due to their voltage source behavior and emulated swing dynamics,GFM converters may encounter low-frequency oscillations(LFOs)when connected to strong grids,which belongs to the self-stability problem of GFM converters.Moreover,GFM converters will also interact with grid-following(GFL)converters and thus impact the mid-frequency oscillations(MFOs)induced by phase-locked loops(PLLs).It has been preliminarily shown in the literature that GFM converters can help stabilize the PLL-induced MFOs,but currently,there is a lack of systematic design methods to coordinate the self-stability and stabilizing ability of GFM converters.This paper addresses this gap by revisiting the impedance model of a typical GFM converter and briefly analyze the oscillations caused by converters.Based on our analysis,we propose a frequency-partitioned synthesis design framework to enable dynamic virtual impedance(DVI)in GFM converters,aiming to enhance their self-stability and stabilizing ability simultaneously.Particularly,a self-stabilizing module is designed to ensure robust device-level damping,with control parameters auto-tuned using H∞methods.In parallel,a stabilizing module is introduced to stabilize GFL converters and enhance the system-level stability,which utilizes a perceive-and-optimize tuning strategy.Simulation results validate the effectiveness of the proposed synthesis DVI framework. 展开更多
关键词 Control synthesis dynamic virtual impedance grid-forming converters self-stability stabilizing ability
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Multi-phase Stacked Interleaved Buck Converter for Hydrogen-production Electrolysis with Low-voltage-stress Ripple Compensation Circuit
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作者 Le Sun Zhaoguo Liu +2 位作者 Xiaoqiang Guo Xiaochen Wang Lichong Wang 《CSEE Journal of Power and Energy Systems》 2026年第1期401-410,共10页
A multi-phase stacked interleaved buck converter(SIBC)is suitable for large-power water electrolysis applications due to its merits of high current output capability and zero output current ripple.However,the auxiliar... A multi-phase stacked interleaved buck converter(SIBC)is suitable for large-power water electrolysis applications due to its merits of high current output capability and zero output current ripple.However,the auxiliary converter used to compensate for the current ripple still has to withstand high voltage stress.This paper proposes a new multi-phase SIBC applied in the multicarrier energy system integrating electricity,heat,and hydrogen.A resistor-capacitor voltage divider is used to provide the input voltage of the auxiliary converter and as a heater for the thermal loads.Thus,the voltage stress of the auxiliary converter can be reduced at a low cost,and the size of the filter inductor can be reduced.With accurate voltage and current analysis and appropriate parameter design,the voltage stresses of both the switches and capacitors in the auxiliary converter can be further limited within an expected range.The experimental results verify the correctness of the topology,modulation,analysis,and design methods.A comparison with the conventional method is made in terms of cost,volume,and efficiency to show the advantages of the proposed method. 展开更多
关键词 Current ripple elimination low voltage stress multicarrier energy system stacked interleaved buck converter
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Fault Current Elimination for Modular Multilevel DC/DC Converter Based on Hybrid HBSM and TDM
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作者 Haijin Liu Weijie Wen +4 位作者 Rui Lyu He Yang Jiawei He Botong Li Bin Li 《CSEE Journal of Power and Energy Systems》 2026年第1期534-546,共13页
As key equipment in medium voltage DC(MVDC)systems,modular multilevel AC/DC and DC/DC converters(MM-AC/DC,MM-DC/DC)have drawn marvelous attractions.However,research on DC fault ride-through focuses on MM-AC/DC,and the... As key equipment in medium voltage DC(MVDC)systems,modular multilevel AC/DC and DC/DC converters(MM-AC/DC,MM-DC/DC)have drawn marvelous attractions.However,research on DC fault ride-through focuses on MM-AC/DC,and the fault current elimination for MM-DC/DC remains a research gap,which limits the wide application of the MVDC system.To fulfil this research gap,the contribution of this paper is revealing the fault current characteristics of MM-DC/DC based on half-bridge and full-bridge submodules(HBSM and FBSM)and proposing a novel MM-DC/DC based on hybrid HBSM and thyristor-diode module(TDM).By integrating TDM in the upper bridge arm of one phase and the down bridge arm of the other phase in MM-DC/DC,the MM-DC/DC achieves self-elimination of fault currents.The basic concept is using the energy at the healthy side to modulate a reverse voltage source(RVS)at the faulty side of MM-DC/DC,forcing fault current through TDM pass across zero.TDM can extinguish the resulting fault current.The parameter design and control strategy of the novel MM-DC/DC are discussed.Simulation is carried out for verification,and the results show that fault current can be eliminated within several milliseconds without causing excessive operating losses and costs. 展开更多
关键词 dC circuit breaker dC fault ride-through modular multilevel dC/dC converter relay protection
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Hardware-Algorithm Co-Design:SiC Bidirectional Converters with MPC-Fuzzy Logic Control for Robust Operation of Solar-Powered EV Hubs
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作者 Wan Chen Zhi Liu +6 位作者 Yingxue Ma Cuicui Wang Xinfa Gu Baolian Liu Lei Shen Hui Huang Jie Ji 《Energy Engineering》 2026年第3期96-116,共21页
In order to solve the problems of slow dynamic response and difficult multi-source coordination of solar electric vehicle charging stations under intermittent renewable energy,this paper proposes a hardware-algorithm ... In order to solve the problems of slow dynamic response and difficult multi-source coordination of solar electric vehicle charging stations under intermittent renewable energy,this paper proposes a hardware-algorithm co-design framework:the T-type three-level bidirectional converter(100 kHz switching frequency)based on silicon carbide(SiC)MOSFET is deeply integrated with fuzzy model predictive control(Fuzzy-MPC).At the hardware level,the switching trajectory and resonance suppression circuit(attenuation resonance peak 18 dB)are optimized,and the total loss is reduced by 23%compared with the traditional silicon-based IGBT.At the algorithm level,the adaptive parameter update mechanism and multi-objective rolling optimization are adopted,and the 5 ms level dynamic power allocation is realized by relying on edge computing.Experiments on 800 V DC microgrid(including 600 kW photovoltaic and 150 A·h energy storage)built based on MATLAB/Simulink hardware-in-the-loop(HIL)platform show that the system shortens the battery charging time from 42 to 28 min(the charging speed is increased by 33%).Through the 78%valley power utilization rate,the power purchase cost of high-priced power grids was significantly reduced,and the levelized electricity price decreased by 10.3%;Under the irradiation fluctuation,the renewable energy consumption rate increases by 10.1%,and the DC bus voltage fluctuation is stable within±10 V when the load step is±30%.The co-design provides an economically feasible and dynamically robust solution for the efficient integration of PV-ESG-EV in the smart grid. 展开更多
关键词 Power electronics co-design fuzzy-MPC control T-type three-level converter grid-adaptive operation PV-storage-charging integration switching loss compensation
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Integrated diagnosis of abnormal energy consumption in converter steelmaking using GWO-SVM-K-means algorithms
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作者 Fei-Xiang Dai Xiang-Jun Bao +2 位作者 Lu Zhang Xiao-Jing Yang Guang Chen 《Journal of Iron and Steel Research International》 2026年第1期458-468,共11页
To address the issue of abnormal energy consumption fluctuations in the converter steelmaking process,an integrated diagnostic method combining the gray wolf optimization(GWO)algorithm,support vector machine(SVM),and ... To address the issue of abnormal energy consumption fluctuations in the converter steelmaking process,an integrated diagnostic method combining the gray wolf optimization(GWO)algorithm,support vector machine(SVM),and K-means clustering was proposed.Eight input parameters—derived from molten iron conditions and external factors—were selected as feature variables.A GWO-SVM model was developed to accurately predict the energy consumption of individual heats.Based on the prediction results,the mean absolute percentage error and maximum relative error of the test set were employed as criteria to identify heats with abnormal energy usage.For these heats,the K-means clustering algorithm was used to determine benchmark values of influencing factors from similar steel grades,enabling root-cause diagnosis of excessive energy consumption.The proposed method was applied to real production data from a converter in a steel plant.The analysis reveals that heat sample No.44 exhibits abnormal energy consumption,due to gas recovery being 1430.28 kg of standard coal below the benchmark level.A secondary contributing factor is a steam recovery shortfall of 237.99 kg of standard coal.This integrated approach offers a scientifically grounded tool for energy management in converter operations and provides valuable guidance for optimizing process parameters and enhancing energy efficiency. 展开更多
关键词 converter smelting process Abnormal energy diagnosis Gray wolf optimization algorithm Support vector machine K-means clustering algorithm
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Different Types of Electrical Generators for Converting Wave Energy into Electrical Energy–A Review
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作者 Jawad Faiz Shahryar Haghvirdiloo Ali Ghaffarpour 《哈尔滨工程大学学报(英文版)》 2025年第1期76-97,共22页
This review paper examines the various types of electrical generators used to convert wave energy into electrical energy.The focus is on both linear and rotary generators,including their design principles,operational ... This review paper examines the various types of electrical generators used to convert wave energy into electrical energy.The focus is on both linear and rotary generators,including their design principles,operational efficiencies,and technological advancements.Linear generators,such as Induction,permanent magnet synchronous,and switched reluctance types,are highlighted for their direct conversion capability,eliminating the need for mechanical gearboxes.Rotary Induction generators,permanent magnet synchronous generators,and doubly-fed Induction generators are evaluated for their established engineering principles and integration with existing grid infrastructure.The paper discusses the historical development,environmental benefits,and ongoing advancements in wave energy technologies,emphasizing the increasing feasibility and scalability of wave energy as a renewable source.Through a comprehensive analysis,this review provides insights into the current state and future prospects of electrical generators in wave energy conversion,underscoring their potential to significantly reduce reliance on fossil fuels and mitigate environmental impacts. 展开更多
关键词 Wave energy Rotary generators Linear generators Control systems Wave energy converters
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高剂量维生素D在儿童短肠综合征合并维生素D不足/缺乏中的应用
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作者 吴青青 曹毅 +4 位作者 陆丽娜 陶怡菁 冯海霞 颜伟慧 王莹 《上海交通大学学报(医学版)》 北大核心 2026年第1期54-59,共6页
目的·探讨单次高剂量肌内注射途径补充维生素D对儿童短肠综合征(short bowel syndrome,SBS)合并维生素D不足/缺乏的安全性和有效性。方法·回顾性纳入32例SBS合并维生素D不足/缺乏的儿童。当患儿血清25-羟维生素D[25-hydroxyvi... 目的·探讨单次高剂量肌内注射途径补充维生素D对儿童短肠综合征(short bowel syndrome,SBS)合并维生素D不足/缺乏的安全性和有效性。方法·回顾性纳入32例SBS合并维生素D不足/缺乏的儿童。当患儿血清25-羟维生素D[25-hydroxyvitamin D,25-(OH)D]浓度低于50 nmol/L时,通过肌内注射途径补充200000 IU的维生素D2。收集患儿的临床资料(性别、年龄、原发疾病、小肠剩余长度、是否保留回盲瓣以及结肠是否完整等),记录肌内注射部位皮肤情况,以及维生素D补充前和补充后1个月的血清25-(OH)D、钙、磷和碱性磷酸酶水平状况。结果·SBS患儿入组时的中位年龄为5.0(3.0,7.0)个月。小肠闭锁和坏死性小肠结肠炎是导致SBS的主要原因(分别占28.13%和21.88%),剩余小肠平均长度为(57.27±24.55)cm。在补充维生素D之前,65.63%(21/32)的患儿存在维生素D缺乏,34.38%(11/32)的患儿存在维生素D不足。在补充维生素D之后,患儿25-(OH)D水平由28.87 nmol/L显著升高至53.10 nmol/L(P<0.001);在维生素D不足的患儿中,25-(OH)D水平从37.30 nmol/L显著升高至58.51 nmol/L(P=0.010);而在维生素D缺乏的患儿中,该水平从26.91 nmol/L显著升高至44.82 nmol/L(P<0.001);62.50%(20/32)的患儿25-(OH)D浓度达到正常水平。所有患儿在研究期间均未出现维生素D中毒、高钙血症、皮肤硬结或局部感染等并发症。结论·单次、高剂量(200000 IU)肌内注射途径补充维生素D,可以安全、有效地改善SBS合并维生素D不足/缺乏婴儿的维生素D水平。 展开更多
关键词 短肠综合征 儿童 高剂量 维生素d
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基于金属纳米光栅结构修饰的D型光纤表面等离激元共振超材料传感器研究
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作者 刘琨 熊艺扬 +8 位作者 井建迎 朱枫彤 肖璐 战晓寒 刘津畅 江俊峰 徐天华 王双 刘铁根 《量子电子学报》 北大核心 2026年第1期141-150,共10页
超材料因其独特的亚波长结构设计和独特的电磁响应特性,在提升表面等离激元共振(Surface Plasmon Resonance,SPR)传感器灵敏度方面具有广阔前景。本文设计了一款金属纳米光栅结构修饰的D型光纤SPR超材料传感器,并对折射率范围在1.332~1.... 超材料因其独特的亚波长结构设计和独特的电磁响应特性,在提升表面等离激元共振(Surface Plasmon Resonance,SPR)传感器灵敏度方面具有广阔前景。本文设计了一款金属纳米光栅结构修饰的D型光纤SPR超材料传感器,并对折射率范围在1.332~1.344的低折射率溶液进行了传感检测。首先,基于倏逝波和表面等离极化激元(Surface Plasmon Polaritons,SPPs)的光波矢特性,对D型光纤SPR传感器进行了理论分析,绘制得到不同折射率下共振波长随入射角度变化的解析解曲线,以便研究光纤中不同传导模式下的SPR激发条件。进而建立了D型光纤SPR超材料传感器二维有限元仿真模型进行模式分析研究,计算了模式损耗和传感器的灵敏度。最后,基于前述的仿真模型,具体构建了分别为以不同间隔的双条带或者单条带为金属光栅单元的传感器,以及使用银/铜替代金,作为金属连续层和金属光栅材料时的传感器,对比探究了这些传感器的灵敏度性能。研究结果表明,改变双条带光栅单元的条带间隔,对灵敏度的影响并不显著,与光栅单元为单条带的传感器灵敏度几乎一致;使用银替代金作为连续金属层材料时,传感器的灵敏度性能达到最优,可达1800 nm·RIU^(-1)。 展开更多
关键词 表面等离激元共振 灵敏度优化 金属纳米光栅 d型光纤
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拉萨市不同孕期妇女血清25羟基维生素D水平的比较
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作者 尼玛顿珠 扎西央宗 +5 位作者 边珍 益西措姆 支张卓玛 詹明君 巴桑央吉 秦绪珍 《基础医学与临床》 2026年第1期120-123,共4页
目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期... 目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期体检妇女为正常对照组,采用雅培i2000化学发光仪检测血清25-(OH)D水平,用SPSS统计学软件进行统计分析。结果367例孕期妇女血清25-(OH)D总体水平为11.5(8.5,17.3)ng/mL。VD充足、不足、缺乏分别占16.6%、30.0%、53.4%;209例健康对照组妇女血清25-(OH)D总体水平为9.9(7.7,13.6)ng/mL。VD充足、不足、缺乏分别占6.7%、27.8%、65.5%。9~13^(+6)周、15~20^(+6)周孕期妇女血清25-(OH)D水平比较差异无统计学意义。结论拉萨市孕期和未妊娠育龄妇女普遍存在VD不足或缺乏现象,应在备孕及怀孕期间补充VD。 展开更多
关键词 孕妇 25羟基维生素d 维生素d
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甲型流感病毒感染相关危险因素及其25-羟基维生素D与血常规参数表达
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作者 于丽瑞 黄玉焕 周曼丽 《病毒学报》 北大核心 2026年第1期200-206,共7页
目的分析甲型流感病毒(INFA)感染相关危险因素及其25-羟基维生素D[25(OH)D]与血常规参数表达特点。方法选取我院2022年10月-2024年9月收治的212例有流感症状患儿,根据上呼吸道核酸六项检测结果分为INFA感染组(n=55)和INFA未感染组(n=15... 目的分析甲型流感病毒(INFA)感染相关危险因素及其25-羟基维生素D[25(OH)D]与血常规参数表达特点。方法选取我院2022年10月-2024年9月收治的212例有流感症状患儿,根据上呼吸道核酸六项检测结果分为INFA感染组(n=55)和INFA未感染组(n=157),采用Logistic回归模型分析INFA感染相关危险因素,采用ROC曲线分析预测变量准确性。结果212例患儿中,INFA感染55例(25.94%)。多因素结果显示:年龄、热程、咳嗽咳痰、喘息、未接种流感疫苗、住院时间是INFA感染的独立影响因素(P<0.05)。策树模型显示住院时间(≥7d)是重要预测因子。ROC分析结果显示:PLT、WBC、LYMPH、NEUT、MON、25(OH)D、HCT、MCV、Hb、CRP、SAA指标预测PICU中INFA感染均具有统计学意义(P<0.05)。结论PICU中INFA感染患儿早期具显著临床特征,应高度关注年龄、热程、咳嗽咳痰、喘息、未接种流感疫苗、住院时间等因素,加强血清25(OH)D及血常规水平监测,以预防INFA感染发生。 展开更多
关键词 甲型流感病毒感染 危险因素 25-羟基维生素d 血常规
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胎次对中国荷斯坦牛305 d产奶量及乳成分的影响
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作者 张丽 尤吉喆 +2 位作者 谢家怡 刘丽霞 王瑞 《中国草食动物科学》 北大核心 2026年第2期121-126,共6页
为了准确应用奶牛生产性能测定(DHI)报告,有针对性地提高全群泌乳水平,试验通过对宁夏某牛场7369条中国荷斯坦牛的DHI记录进行方差分析和相关与回归分析,探讨胎次对305 d产奶量和乳成分的影响及其相关关系。结果表明,胎次极显著地影响... 为了准确应用奶牛生产性能测定(DHI)报告,有针对性地提高全群泌乳水平,试验通过对宁夏某牛场7369条中国荷斯坦牛的DHI记录进行方差分析和相关与回归分析,探讨胎次对305 d产奶量和乳成分的影响及其相关关系。结果表明,胎次极显著地影响中国荷斯坦牛305 d的产奶量和乳成分(P<0.01);第4胎中国荷斯坦牛305 d产奶量、第2胎乳蛋白率、第1胎乳糖率和第7胎尿素氮含量均极显著高于其他胎次(P<0.01);乳脂率随着胎次的增加呈现先下降后上升的趋势,全群平均乳脂率保持在3.57%以上;随着胎次的增加体细胞数变化波动较大,第6胎达到最高。胎次与产奶量、体细胞数呈极显著正相关(P<0.01),与乳脂率、乳蛋白率、乳糖率、总固体含量均呈极显著负相关(P<0.01);乳脂率与乳蛋白率呈极显著正相关(P<0.01);乳蛋白率与乳糖率呈极显著负相关(P<0.01),与体细胞数、尿素氮、总固体呈极显著正相关(P<0.01);乳中体细胞数与乳糖率、尿素氮含量呈极显著负相关(P<0.01);尿素氮与乳糖率呈极显著正相关(P<0.01);乳糖率与乳脂率、乳蛋白率、体细胞数呈极显著负相关(P<0.01);总固体含量与乳脂率、乳蛋白率、乳糖率呈极显著正相关(P<0.01),与尿素氮(P<0.01)呈极显著负相关关系。说明胎次对中国荷斯坦牛产奶量和乳成分的影响有一定的变化规律,建议牛场根据变化趋势合理调整奶牛的饲粮配方,从而提高养殖场的管理水平和经济效益。 展开更多
关键词 中国荷斯坦牛 胎次 305 d产奶量 乳成分 相关分析 回归分析
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基于NLRP3/GSDMD信号通路探究栀子厚朴汤及其药对的抗抑郁作用
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作者 陈畅 郭紫文 +3 位作者 宋婷宇 王艳 夏宝妹 陶伟伟 《中国实验方剂学杂志》 北大核心 2026年第6期72-80,共9页
目的:以经典药对配伍研究为切入点,深入探讨中药复方栀子厚朴汤抗抑郁作用的物质基础与配伍规律,并重点阐明其通过调控NOD样受体蛋白3(NLRP3)/消皮素D(GSDMD)信号通路介导的神经炎症反应,改善神经元突触可塑性发挥抗抑郁作用的效应机制... 目的:以经典药对配伍研究为切入点,深入探讨中药复方栀子厚朴汤抗抑郁作用的物质基础与配伍规律,并重点阐明其通过调控NOD样受体蛋白3(NLRP3)/消皮素D(GSDMD)信号通路介导的神经炎症反应,改善神经元突触可塑性发挥抗抑郁作用的效应机制。方法:将C57BL/6J小鼠随机分为空白组、慢性不可预知温和应激(CUMS)抑郁模型组、栀子厚朴汤全方组(6 g·kg^(-1)·d^(-1))、厚朴-枳实药对组(4.2 g·kg^(-1)·d^(-1))、栀子-厚朴药对组(4.2 g·kg^(-1)·d^(-1))、栀子-枳实药对组(3.6 g·kg^(-1)·d^(-1))及阳性药组(氟西汀,12 mg·kg^(-1)·d^(-1)),通过行为学检测评估小鼠抑郁样行为;采用免疫荧光染色标记并定量小鼠前额叶皮层(PFC)组织中小胶质细胞标志物离子钙结合适配器分子1(Iba1)及嘌呤能受体P2X配体门控离子通道7(P2RX7)的表达;应用酶联免疫吸附测定法(ELISA)检测血清和PFC组织中炎症因子白细胞介素(IL-1β)、白细胞介素18(IL-18)水平;蛋白免疫印迹法(Western blot)检测PFC组织中泛连接蛋白1(Panx1)、P2RX7、NLRP3、凋亡相关斑点样蛋白(ASC)、胱天蛋白酶-1(Caspase-1)、GSDMD、突触后致密蛋白95(PSD95)及突触前蛋白突触素1(Synapsin1)的表达;通过高尔基染色评估PFC神经元树突棘密度。结果:与空白组比较,抑郁模型组小鼠表现出显著的抑郁样行为,并且PFC组织中Ibal及P2RX7免疫荧光面积显著增加(P<0.01),血清及PFC中IL-1β、IL-18水平显著升高(P<0.01),PFC组织中Panx1、P2RX7、NLRP3、ASC、Caspase-1、GSDMD蛋白表达显著上调(P<0.01),而PSD95和Synapsin1蛋白表达显著下调(P<0.01),同时神经元树突棘密度显著降低(P<0.01)。与模型组比较,栀子厚朴汤全方组、栀子-厚朴药对组上述各指标均明显改善(P<0.01),栀子-枳实药对组可改善除P2RX7、Caspase-1、GSDMD、PSD95之外的其他上述指标(P<0.05,P<0.01)。而厚朴-枳实药对组与模型组相比,对上述各指标的改善均无统计学意义。结论:栀子厚朴汤及其关键药对,即栀子-厚朴,能有效改善CUMS诱导的小鼠抑郁样行为。其核心抗抑郁机制可能在于通过抑制P2RX7/Panx1信号,阻断NLRP3/GSDMD介导的焦亡通路,从而显著降低炎症因子IL-1β、IL-18的释放;同时上调突触相关蛋白PSD95和Synapsin1的表达并增加树突棘密度,促进突触可塑性的恢复。研究结果提示,栀子在该复方抗抑郁效应中扮演关键角色,且栀子与厚朴的配伍可能是发挥核心治疗作用的主要药对组合。 展开更多
关键词 抑郁症 栀子厚朴汤 药对 NOd样受体蛋白3(NLRP3)炎症小体 消皮素d(GSdMd)
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佛山地区围绝经期妇女维生素D水平及影响因素分析
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作者 陈敏枝 李荔 +2 位作者 刘丹 伍曼玉 朱海燕 《妇儿健康导刊》 2026年第5期185-188,共4页
目的分析佛山地区围绝经期妇女维生素D水平及影响因素。方法回顾性分析2021年4月至2024年7月在佛山市妇幼保健院门诊就诊的300例40~55岁围绝经期妇女的资料,分析其一般资料、症状评分、实验室检查结果、骨密度,采用多因素logistic回归... 目的分析佛山地区围绝经期妇女维生素D水平及影响因素。方法回顾性分析2021年4月至2024年7月在佛山市妇幼保健院门诊就诊的300例40~55岁围绝经期妇女的资料,分析其一般资料、症状评分、实验室检查结果、骨密度,采用多因素logistic回归分析围绝经期妇女维生素D水平的影响因素。结果300例围绝经期妇女的血清25-羟基维生素D[25(OH)D]水平为9.42~56.26 ng/ml,平均(27.10±7.50)ng/ml;维生素D充足100例(33.33%),维生素D不足150例(50.00%),维生素D缺乏50例(16.67%)。三组体重指数(BMI)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、骨密度比较,差异有统计学意义(P<0.05)。多因素logistic回归分析结果显示,BMI、TC、TG和骨密度是维生素D缺乏的危险因素,HDL-C是维生素D缺乏的保护因素(P<0.05)。结论佛山地区围绝经期妇女维生素D不足及缺乏的比例较高,BMI、TC、TG、骨密度、HDL-C是佛山地区围绝经期妇女维生素D水平的影响因素,临床应引起足够重视。 展开更多
关键词 围绝经期 维生素d 影响因素
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昆明地区RhD初筛阴性献血者RHD基因多态性及分子机制研究
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作者 杜霞 李茜 +6 位作者 涂源泉 陈璐 张智慧 彭沫溱 罗臻 寸伟 朱祥明 《临床输血与检验》 2026年第1期97-102,共6页
目的研究昆明地区RhD初筛阴性献血者RHD基因的多态性及其分子机制,为建立区域性献血者RHD基因数据库提供数据支持。方法选择昆明地区2023年11月-2024年8月初筛RhD阴性标本218例,采用间接抗球蛋白试验法(IAT)进行RhD阴性确认,采用盐水试... 目的研究昆明地区RhD初筛阴性献血者RHD基因的多态性及其分子机制,为建立区域性献血者RHD基因数据库提供数据支持。方法选择昆明地区2023年11月-2024年8月初筛RhD阴性标本218例,采用间接抗球蛋白试验法(IAT)进行RhD阴性确认,采用盐水试管法进行RhCE表型鉴定。提取全血基因组DNA,采用PCR-SSP法/SSP荧光PCR染料法进行RHD基因分型,对无法确定基因型的标本进行RHD基因1~10外显子Sanger测序分析。结果检出RhD真阴性表型179例(82.11%),其中RHD*01N.01(RHD全缺失)型154例(86.03%),表型以ccee为主(87.01%);携带非功能性RHD等位基因25例(13.97%),包括RHD*01N.0320例、RHD*01N.163例、RHD*01N.051例、RHD*01N.591例,表型以Ccee为主(64%)。检出D变异型39例(15.89%),其中RHD*DEL1(c.1227G>A)型34例,表型均为C抗原阳性(Ccee 27例,CCee 7例);弱D/部分D型4例,包括RHD*DVI.32例、RHD*weak D type 711例、RHD*weak D type1081例;另检出1例RHD*01/RHD*01N.01,基因型与血清学表型结果不一致。RHD*01N.01女性献血者不规则抗体(主要为抗-D)阳性率9.84%。结论昆明地区RhD初筛阴性献血者RHD基因多态性显著,RhD真阴性比例高于国内部分地区,D变异型以“亚洲型”DEL为主,比例低于国内部分地区。研究结果为本地区RhD阴性和D变异型个体精准输血提供了理论和数据支持。 展开更多
关键词 RHd阴性 d变异型 亚洲型dEL 基因多态性 分子机制
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妊娠期血清维生素D水平的影响因素及与妊娠结局的关系
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作者 杜潘艳 高翠红 +3 位作者 王振荣 李艳华 赵娜 吴景华 《中国妇幼健康研究》 2026年第2期65-71,共7页
目的了解唐山地区孕妇血清维生素D(VD)水平,探讨其影响因素及与妊娠结局的相关性。方法纳入2022年7月—2024年6月于唐山市妇幼保健院妇产科进行妊娠期体检的16138例孕妇作为研究对象,整理研究对象首诊时的基本信息和临床资料,以化学发... 目的了解唐山地区孕妇血清维生素D(VD)水平,探讨其影响因素及与妊娠结局的相关性。方法纳入2022年7月—2024年6月于唐山市妇幼保健院妇产科进行妊娠期体检的16138例孕妇作为研究对象,整理研究对象首诊时的基本信息和临床资料,以化学发光法检测血清25-羟基维生素D_(3)[25-(OH)D_(3)]水平。结果孕妇血清VD水平缺乏11981例(74.24%),不足3387例(20.99%),充足770例(4.77%)。妊娠中期、妊娠晚期血清25-(OH)D_(3)水平低于妊娠早期(t=16.595、9.155,P<0.05);≤36岁孕妇血清25-(OH)D_(3)水平较低,各年龄段间营养状况均较差(F=31.202,P<0.05),>36岁血清25-(OH)D_(3)水平较高,且随年龄增加呈逐渐升高趋势。春季血清25-(OH)D_(3)水平最高,1~12月份中血清25-(OH)D_(3)水平4月(17.02±7.38)ng/mL和10月(17.17±7.85)ng/mL高于其他组(F=2.153,P<0.05),VD缺乏率(71.78%、71.69%)均低于其他组(χ^(2)=45.063,P<0.05);血清25-(OH)D_(3)水平在妊娠期糖尿病和子痫前期均低于正常组,其中子痫前期组最低(t=7.63、3.06,P<0.05);孕妇就诊时血清25-(OH)D_(3)水平对后续胎儿发育不同情况(自然流产、胎儿停育、早产、胎儿发育延迟和正常)间均无统计学差异(P>0.05)。结论孕妇血清维生素D水平偏低,夏秋冬季节、妊娠中期和晚期、年龄≤36岁、妊娠期糖尿病和子痫前期最为显著。建议医生积极指导本地区孕妇合理补充维生素D。 展开更多
关键词 孕妇 维生素d 营养状况 妊娠结局
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维生素D联合丙酸倍氯米松气雾剂治疗对支气管哮喘患儿肺功能的影响
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作者 刘晓娟 张英谦 +4 位作者 吴会芳 张景丽 王莹雪 康军聪 梁慧萍 《成都医学院学报》 2026年第2期310-313,共4页
目的 探讨维生素D联合丙酸倍氯米松气雾剂治疗对支气管哮喘(BA)患儿肺功能的影响。方法 选取2023年1-12月河北省儿童医院收治的104例支气管哮喘患儿作为研究对象,随机分为对照组与干预组,每组52例,分别采用丙酸倍氯米松气雾剂治疗、维生... 目的 探讨维生素D联合丙酸倍氯米松气雾剂治疗对支气管哮喘(BA)患儿肺功能的影响。方法 选取2023年1-12月河北省儿童医院收治的104例支气管哮喘患儿作为研究对象,随机分为对照组与干预组,每组52例,分别采用丙酸倍氯米松气雾剂治疗、维生素D与丙酸倍氯米松气雾剂联合治疗。对比两组临床疗效、免疫功能、肺通气功能、炎症因子、症状缓解情况及不良反应。结果 干预组总有效率较对照组高(94.23%vs 80.77%,P<0.05),患儿喘息、咳嗽等症状评分降低(P<0.05)。治疗后干预组CD4^(+)、CD4^(+)/CD8^(+)、第1秒用力呼气容积(FEV1)、用力呼气量(FVC)、呼气流量峰值(PEF)水平较对照组升高(P<0.05),且干预组CD8^(+)、白细胞介素-4(IL-4)、C反应蛋白(CRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平较对照组降低(P<0.05);两组不良反应发生率差异无统计学意义(P>0.05)。结论 BA患儿应用维生素D与丙酸倍氯米松气雾剂联合治疗可明显改善肺通气功能。 展开更多
关键词 维生素d 丙酸倍氯米松气雾剂 支气管哮喘 肺功能
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