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Digitalization of inverting filter shaping circuit for nuclear pulse signals

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Nuclear Science and Techniques 2020年第9期31卷 16-24页

作者： huai-qiang zhang Hong-Tao Shi Zhuo-Dai Li Yu-Wen Li State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

In the design of filter shaping circuits for nuclear pulse signals,inverting filter shaping circuits perform better than non-inverting filter shaping *** these circuits facilitate changing the phase of a pulse signal,they are widely used in processing nuclear pulse *** this study,the transfer functions of four types of inverting filter shaping circuits,namely the common inverting filter shaping,improved inverting filter shaping,multiple feedback low-pass filter shaping,and third-order multiple feedback low-pass filter shaping,in the Laplacian domain,are *** establish the numerical recursive function models and digitalize the four circuits,obtain the transfer functions in the Z domain,and analyze the filter performance and amplitude-frequency response characteristics in the frequency *** on the actual nuclear pulse signal of the Si-PIN detector,we realize four types of inverting digital *** results show that under the same shaping parameters,the common inverting digital shaping has better amplitude extraction characteristics,the third-order multiple feedback low-pass digital shaping has better noise suppression performance,and the multiple feedback digital shaping takes into account both pulse amplitude extraction and noise suppression performance.

关键词： Nuclear pulse signal Inverting filter shaping circuit Digital shaping Amplitude-frequency response

Optimal parameter choice of CR–RC^m digital filter in nuclear pulse processing

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Nuclear Science and Techniques 2019年第7期30卷 42-46页

作者： huai-qiang zhang Zhuo-Dai Li Bin Tang He-Xi Wu Engineering Research Center of Nuclear Technology Application (East China University of Technology) Ministry of Education Nanchang 330013 China School of Nuclear Science and Engineering East China University of Technology Nanchang 330013 China

CR–RCm filters are widely used in nuclear energy spectrum measurement systems. The choice of parameters of a CR–RCm digital filter directly affects its performance in terms of energy resolution and pulse count rate in digital nuclear spectrometer systems. A numerical recursive model of a CR differential circuit and RC integration circuit is derived, which shows that the shaping result of CR–RCm is determined by the adjustment parameter (k, it determines the shaping time of the shaper) and the integral number (m). Furthermore, the amplitude– frequency response of CR–RC^m is analyzed, which shows that it is a bandpass filter;the larger the shaping parameters (k and m), the narrower is the frequency band. CR–RC^m digital Gaussian shaping is performed on the actual sampled nuclear pulse signal under different shaping parameters. The energy spectrum of 137Cs is measured based on the LaBr3(Ce) detector under different parameters. The results show that the larger the shaping parameters (m and k), the closer the shaping result is to Gaussian shape, the wider is the shaped pulse, the higher is the energy resolution, and the lower is the pulse count rate. For the same batch of pulse signals, the energy resolution is increased from 3.8 to 3.5%, and the full energy peak area is reduced from 7815 to 6503. Thus, the optimal shaping parameters are m -3 and k -0.95. These research results can provide a design reference for the development of digital nuclear spectrometer measurement systems.

关键词： CR-RCm digital filter Nuclear pulse signal Gaussian shaping Energy resolution

RBF Neural Network Case Teaching Research

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RBF Neural Network Case Teaching Research

玻璃体切除黄斑前膜剥除联合内界膜剥除对特发性黄斑前膜患者疗效的影响

Advances in Information Technology and Education

作者： Jing Bing Li huai qiang zhang You Ling Zhou Yong Bai School of Information Science and Technology Hainan University

In this paper, the RBF neural network case teaching has been studied. In the actual teaching process, we find it more difficult for student to learn the course, duing to the RBF neural network curriculum theory is more stronger. Many students do not know how to use the theory to solve practical ***, we equip students with basic knowledge of RBF neural network through case teaching. In this paper, a RBF neural network example has been analysised and applied to enable the students to learn RBF neural network. Teaching practice shows that case teaching can achieve better teaching effectiveness.

关键词： Case teaching RBF neural network Tourists quantity

来源： cnki会议评论

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国际眼科杂志 2021年第12期21卷 2066-2071页

作者：刘华孙佳张怀强陈芳中国河北省唐山市眼科医院 063000

目的:分析玻璃体切除黄斑前膜剥除术联合与不联合内界膜(ILM)剥除对特发性黄斑前膜(IMEM)患者脉络膜厚度、视力和视物变形的影响。方法:前瞻性研究。收集2016-01/2020-01在本院诊治的IMEM患者88例88眼,按随机数字表法分两组:观察组44眼... 详细信息

目的:分析玻璃体切除黄斑前膜剥除术联合与不联合内界膜(ILM)剥除对特发性黄斑前膜(IMEM)患者脉络膜厚度、视力和视物变形的影响。方法:前瞻性研究。收集2016-01/2020-01在本院诊治的IMEM患者88例88眼,按随机数字表法分两组:观察组44眼接受玻璃体切除黄斑前膜剥除术联合内界膜剥除治疗,对照组44眼仅接受玻璃体切除黄斑前膜剥除术治疗。比较两组患者手术前后脉络膜厚度、视力和视物变形、黄斑中心凹厚度(CMT)、椭圆体区连续性(EZ)及并发症。结果:与术前比较,两组患者术后3、6mo时的黄斑中心凹脉络膜厚度(SFCT)、距黄斑中心凹鼻侧1000μm处脉络膜厚度(NFCT)及距黄斑中心凹颞侧1000μm处脉络膜厚度(TFCT)均明显下降(P0.05);与术前比较,两组患者最佳矫正视力(BCVA)改善,光敏感度(MS)上升,观察组患者黄斑暗点数(SP)上升,对照组患者SP下降,观察组术后1、3、6mo时的MS明显低于对照组,SP高于对照组(均P0.05);两组术后1、3、6mo时的CMT较术前均明显下降,观察组术后3、6mo时的CMT均高于对照组(均P0.05)。结论:玻璃体切除黄斑前膜剥除治疗IMEM时,无论是否联合ILM剥除均可取得良好的视力并改善视物变形,且对脉络膜厚度的影响及安全性相当;但联合ILM剥除具更低的光敏感度和更高的暗点数,术后CMT更厚,并未体现出显著优越性。

关键词：特发性黄斑前膜玻璃体切除黄斑前膜剥除术内界膜剥除脉络膜厚度视力视物变形

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong zhang Zhiying Chen Yinyi Xiong Qin Zhou Ling-qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： qiang Liu Xiang Li Shen Du Ming Gao Yanbin Yin Jiongming zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli zhang Tian Li Jie Miao Zhina zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei zhang Haiting Li qiang Su Junhong Guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing Guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

不同分期糖尿病视网膜病变患者黄斑区结构和微血管改变定量分析

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国际眼科杂志 2021年第11期21卷 1948-1951页

作者：刘长颖李玲娜张怀强刘庆华梁丽赵旭铮中国河北省唐山市眼科医院 063000

目的:通过光相干断层扫描(OCT)和光相干断层扫描血管造影(OCTA)检查,观察不同分期糖尿病视网膜病变(DR)患者黄斑区神经节细胞-内丛状层(GCIPL)厚度及各象限视网膜浅层毛细血管密度特征并作定量分析。方法:回顾性病例对照研究。选取2019-... 详细信息

目的:通过光相干断层扫描(OCT)和光相干断层扫描血管造影(OCTA)检查,观察不同分期糖尿病视网膜病变(DR)患者黄斑区神经节细胞-内丛状层(GCIPL)厚度及各象限视网膜浅层毛细血管密度特征并作定量分析。方法:回顾性病例对照研究。选取2019-12/2020-05我院确诊DR患者33例54眼,并根据眼底情况分为无糖尿病视网膜病变(NDR)组6例8眼、非增殖型糖尿病视网膜病变(NPDR)组18例28眼和增殖型糖尿病视网膜病变(PDR)组9例18眼。选取同期与患者年龄相匹配的健康志愿者18例26眼作为对照组。观察并定量分析不同分期DR患者黄斑区GCIPL厚度及各象限视网膜浅层毛细血管线性密度(VD)和血管灌注密度(PD)。结果:DR组患者黄斑区各象限视网膜浅层毛细血管VD、PD及GCIPL厚度最小值均小于对照组(P<0.05)。不同分期DR患者黄斑区GCIPL厚度最小值及各象限视网膜浅层毛细血管VD组间比较均有差异(P<0.05),下方视网膜浅层毛细血管VD对DR的诊断价值最高(AUC=0.807、最佳诊断界限值为18.60mm^(-1)、灵敏度为0.923、特异度为0.648)。DR患者黄斑区GCIPL厚度最小值与各象限视网膜浅层毛细血管VD均呈正相关(r=0.342、0.480、0.384、0.342,均P<0.05)。结论:OCT结合OCTA检查为早期评估及定期随访DR的进展提供了可重复、可定量的检测方法和监测指标。

关键词：糖尿病视网膜病变神经节细胞-内丛状层厚度视网膜浅层毛细血管密度