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基于正则化参数优化和边界聚类的电阻抗成像研究
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作者 王苏煜 戎舟 袁晶晶 《国外电子测量技术》 2024年第1期94-100,共7页
电阻抗成像是一种无损伤的功能成像技术,由于逆问题具有不适定性、不稳定性等特点,往往存在重构图像的分辨率不高、伪影较大等问题。将Tikhonov和全变量(TV)两种正则化算法的罚函数进行组合应用,提出将粒子群算法用于组合罚函数的正则... 电阻抗成像是一种无损伤的功能成像技术,由于逆问题具有不适定性、不稳定性等特点,往往存在重构图像的分辨率不高、伪影较大等问题。将Tikhonov和全变量(TV)两种正则化算法的罚函数进行组合应用,提出将粒子群算法用于组合罚函数的正则化参数优化,把图像质量指标(artifact level, AL)作为粒子群算法的适应度值,从而确定最优正则化参数,通过牛顿迭代法获得电导率,为了进一步去除伪影,将Niblack算法与边界聚类算法相结合,对求得的电导率进行处理,得到最终的电导率分布。仿真和实测结果均表明,该方法重建的图像能够更加准确地反映电场内目标物体的位置信息,有效的抑制伪影,提高了重建效果。 展开更多
关键词 电阻抗成像 逆问题 Tikhonov正则化算法 粒子群算法 边界聚类算法 图像重建
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Study of leakage current degradation based on stacking faults expansion in irradiated SiC junction barrier Schottky diodes
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作者 Maojiu Luo Yourun Zhang +5 位作者 Yucheng Wang Hang Chen rong zhou Zhi Wang Chao Lu Bo Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期458-464,共7页
A comprehensive investigation was conducted to explore the degradation mechanism of leakage current in SiC junction barrier Schottky(JBS)diodes under heavy ion irradiation.We propose and verify that the generation of ... A comprehensive investigation was conducted to explore the degradation mechanism of leakage current in SiC junction barrier Schottky(JBS)diodes under heavy ion irradiation.We propose and verify that the generation of stacking faults(SFs)induced by the recombination of massive electron-hole pairs during irradiation is the cause of reverse leakage current degradation based on experiments results.The irradiation experiment was carried out based on Ta ions with high linear energy transfer(LET)of 90.5 MeV/(mg/cm^(2)).It is observed that the leakage current of the diode undergoes the permanent increase during irradiation when biased at 20%of the rated reverse voltage.Micro-PL spectroscopy and PL micro-imaging were utilized to detect the presence of SFs in the irradiated SiC JBS diodes.We combined the degraded performance of irradiated samples with SFs introduced by heavy ion irradiation.Finally,three-dimensional(3D)TCAD simulation was employed to evaluate the excessive electron-hole pairs(EHPs)concentration excited by heavy ion irradiation.It was observed that the excessive hole concentration under irradiation exceeded significantly the threshold hole concentration necessary for the expansion of SFs in the substrate.The proposed mechanism suggests that the process and material characteristics of the silicon carbide should be considered in order to reinforcing against the single event effect of SiC power devices. 展开更多
关键词 4H-SiC JBS diode heavy ion irradiation single event effect single event leakage current degradation
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YVDD Mutation of Hepatitis B Virus, a Dominant Lamivudine-Resistant Type in Guangzhou, South China
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作者 Zhi-ying OU rong zhou Yun-shao HE 《Virologica Sinica》 SCIE CAS CSCD 2008年第3期218-225,共8页
The epidemiological effects of native and mutated YMDD motif in the HBV genome under the selective pressure of lamivudine were investigated. YMDD wild and mutation motif in HBV genome were detected by flow through rev... The epidemiological effects of native and mutated YMDD motif in the HBV genome under the selective pressure of lamivudine were investigated. YMDD wild and mutation motif in HBV genome were detected by flow through reverse dot blots (PT-RDB) with KaiPuTM DNA HybriMax Rapid Hybridization Machine based on the principle of "Flow-through hybridization" and by the traditional Reverse Dot Blot assay. Sera from 1 021 suspected lamivudine-resistant chronic HBV carriers after more than 8 months of lamivudine therapy and the corresponding archived sera were collected and assayed. We found 35.94% were single type infections with 8.03% YMDD, 7.93% YIDD and 19.98% YVDD. It was also found that 64.06% were mixed infections including 1.96% YMDD and YIDD, 51.62% YMDD and YVDD, 1.96% YIDD and YVDD, 8.52% YMDD, YIDD and YVDD. The levels of infections containing YVDD motif reached 82.08%. The pretreatment infectious status were: YMDD single infection was 36.93%; YIDD single infection was 6.07%; YVDD single infection was 17.04%; YMDD and YIDD mixed infection was 0.97%; YMDD and YVDD mixed infection was 33.99%; YIDD and YVDD mixed infection was 0.98%; YMDD, YIDD and YVDD mixed infection was 4.02%. Infections containing YVDD motif were only 56.03%. The 34.32% mutation rate of YMDD motif to YVDD was significantly higher than the 10.97% of YMDD to YIDD (U=10.98, P〈0.05), as estimated by Mann-Whitney U-test for non-parametric data. HBV containing YVDD motif might have an evolutionary ascendancy and become the dominant type under the selective pressure of lamivudine. 展开更多
关键词 HBV Lamivudine resistance PT-RDB MUTATION Evolution
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The complete genomic sequence analysis of human norovirus NVgz01 strain in Guangzhou
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作者 QI Yi ZENG JIA YU ZHONG +8 位作者 XIAO LI YAN LI SU BING ZHU YI CHEN TAO LIN MI Sin XIAO HUI YING CHENG rong zhou SI TANG GONG 《Journal of Microbiology and Immunology》 2007年第1期29-34,共6页
The aim of this study is to explore the genomic molecular organization and genogroup of human nomvirus from infected infants in Guangzhou of China. Primers were designed according to the genomic sequence of norovims i... The aim of this study is to explore the genomic molecular organization and genogroup of human nomvirus from infected infants in Guangzhou of China. Primers were designed according to the genomic sequence of norovims in the GenBank, and the nomvirus genome was amplified by RT-PCR. The PCR- products were cloned into T vector and sequenced, and the genomic nucleotide sequences were analyzed with the programs CLUSTAL W/X, DNASTAR and RAT (Recombination Analysis Tool). The NVgz01 strain genome is 7558 bp in length and encodes three open reading frames (GenBank accession No. is DQ369797). The genomic sequences of NVgz01 were compared with those of nomvirus in GenBank, which revealed that the homology with genogroup Ⅱ ranges between 76%-90%, and genogroup Ⅰ between 43%-44%. The ORF1 region shared 94% and 88% identity with Mc37 and Famiington strains, respectively; the capsid region (ORF2) shared 65% and 94% identity with Mc37 and Farmington strains, respectively. Phylogenetic trees were reconstructed by the neighbor-joining method. Comparative complete sequence analysis of the NVgz01 with reported human norovirus genomic sequences revealed that this isolate belongs to genogroup Ⅱ . The ORF1 and ORF2 regions shared different identity with Mc37 and Fannington strains, suggesting NVgz01 could be a recombinant virus. 展开更多
关键词 Human norovirus Genome Sequence analysis Recombinant
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The complete genomic sequence analysis of genotype 4 human astrovirus HASTVgz01 strain in Guangzhou
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作者 BING ZHU JIA YU ZHONG +5 位作者 XIAO LI YI CHEN TAO LIN ZAO HE WU rong zhou SI TANG GONG 《Journal of Microbiology and Immunology》 2006年第3期173-176,共4页
To analyze the genomic molecular structure and genotype of human astrovirus isolated from infant in Guangzhou of China, the primers were designed based on the genomic sequence of astrovirus from the C, enBank and the ... To analyze the genomic molecular structure and genotype of human astrovirus isolated from infant in Guangzhou of China, the primers were designed based on the genomic sequence of astrovirus from the C, enBank and the target sequence were amplified by RT-PCR. Then the PCR-products were cloned to T vector and sequenced. The genomic nucleotide sequences were analyzed by the programs CLUSTAL W and DNASTAR. It was found that the full genomic length of HASTVgz01 strain was 6721 bp and the ORFs were 6558 bp. The 5' and 3'UTR were 82 and 81 nucleotides. The genome included 3 open reading frames (ORFs) : ORFla, ORFlb and ORF2. The 5'-terminal ORFla started at nueleotide 83 and extended to nucleotide 2845. ORFlb (nt 2785 to nt 4332) overlaped ORFla by 61 nueleotides. The 3'-terminal ORF2 began at nucleotide 4325 and terminated at nucleotide 6640. ORF2 had 2316 nucleotides. Compared with other astrovirus sequences in GenBank, the homology of the amino acid sequence of ORF2 of HASTVgz01 strain with that of serotype 4 was 93%. Homology with other serotypes ranged from 61% to 70%. The complete nucleotide sequence of astrovirus HASTVgz01 strain isolated from Guangzhou in China was 6721 bp in length, GenBank accession NO. DQ344027. Comparing the ORF2 of astrovirus HASTVgz01 with the known sequences of types 1-8 the highest homology was serotype 4 (93%). Comparative sequence analysis of the HASTVgz01 ORF2 with the reported human astrovirus sequences revealed that the isolated astrovirus belongs to genotype (serotype) 4. 展开更多
关键词 Human astrovirus Genome Genotype 4 Sequence analysis
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The Effect of Pore Solution on the Hysteretic Curve of Expansive Soil under Cyclic Loading
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作者 Xinshan Zhuang Wu Wen +2 位作者 rong zhou Gaoliang Tao Wentao Li 《Fluid Dynamics & Materials Processing》 EI 2023年第7期1963-1981,共19页
A dynamic triaxial instrument was used to study the effects of different concentrations of sodium chloride and stress amplitudes on the dynamic properties of an expansive soil under cyclic loading.In particular,four p... A dynamic triaxial instrument was used to study the effects of different concentrations of sodium chloride and stress amplitudes on the dynamic properties of an expansive soil under cyclic loading.In particular,four parameters were considered in such a parametric investigation,namely,hysteresis curve morphology characteristic non-closure degreeεp,the ratio of the short and long axisα,the slope of the long axis k and the enclosed area S.The results show that with an increase in the sodium chloride concentration,the soil particle double electric layer becomes thinner,the distance between soil particles decreases,and the whole sample becomes denser.Theεp-N,α-N and S–N relation curves all show a decreasing trend.The ratio of plastic deformation to total deformation grows with increasing the dynamic stress amplitude,and the curves show an upwards trend.The k-N relationship curve displays an increasing trend with the concentration and a general downwards trend as the dynamic stress amplitude is made higher.This also indicates that sodium chloride solutions can improve the engineering properties of expansive soil to a certain extent.With an increase in the vibration times N,the shape of the hysteretic curve becomes narrower,and the whole soil exhibits a cyclic strain hardening.With the help of an exponential function,a model is introduced to predict the relationship between the concentration and the hysteretic curve. 展开更多
关键词 Expansive soil cyclic loading sodium chloride solution hysteretic curve diffuse double-layer
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GRB 220408B:A Three-episode Burst from a Precessing Jet
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作者 Zijian Zhang Yi-Han Iris Yin +27 位作者 Chenyu Wang Xiangyu Ivy Wang Jun Yang Yan-Zhi Meng Zi-Ke Liu Guo-Yin Chen Xiaoping Fu Huaizhong Gao Sihao Li Yihui Liu Xiangyun Long Yong-Chang Ma Xiaofan Pan Yuanze Sun Wei Wu Zirui Yang Zhizhen Ye Xiaoyu Yu Shuheng Zhao Xutao Zheng Tao zhou Qing-Wen Tang Qiurong Yan rong zhou Zhonghai Wang Hua Feng Ming Zeng Bin-Bin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第11期214-224,共11页
Jet precession has previously been proposed to explain the apparently repeating features in the light curves of a few gamma-ray bursts(GRBs).In this paper,we further apply the precession model to a bright GRB 220408B ... Jet precession has previously been proposed to explain the apparently repeating features in the light curves of a few gamma-ray bursts(GRBs).In this paper,we further apply the precession model to a bright GRB 220408B by examining both its temporal and spectral consistency with the predictions of the model.As one of the recently confirmed GRBs observed by our GRID CubeSat mission,GRB 220408B is noteworthy as it exhibits three apparently similar emission episodes.Furthermore,the similarities are reinforced by their strong temporal correlations and similar features in terms of spectral evolution and spectral lags.Our analysis demonstrates that these features can be well explained by the modulated emission of a Fast-Rise-Exponential-Decay(FRED)shape light curve intrinsically produced by a precessing jet with a precession period of 18.4_(-0.2)~(+0.2)s,a nutation period of11.1_(-0.2)~(+0.2)s and viewed off-axis.This study provides a straightforward explanation for the complex yet similar multiepisode GRB light curves. 展开更多
关键词 gamma-rays:general (stars:)gamma-ray burst:individual(GRB 220408B) stars:jets
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Allergic bronchopulmonary aspergillosis with marked peripheral blood eosinophilia and pulmonary eosinophilia:A case report
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作者 Xiao-Xi Zhang rong zhou +4 位作者 Chang Liu Jing Yang Zi-Han Pan Cen-Cen Wu Qiu-Yu Li 《World Journal of Clinical Cases》 SCIE 2023年第11期2457-2463,共7页
BACKGROUND Allergic bronchopulmonary aspergillosis(ABPA)is an immune-related pulmonary disease caused by sensitization of airway by Aspergillus fumigatus.The disease manifests as bronchial asthma and recurring pulmona... BACKGROUND Allergic bronchopulmonary aspergillosis(ABPA)is an immune-related pulmonary disease caused by sensitization of airway by Aspergillus fumigatus.The disease manifests as bronchial asthma and recurring pulmonary shadows,which may be associated with bronchiectasis.The diagnosis of ABPA mainly depends on serological,immunological,and imaging findings.Pathological examination is not necessary but may be required in atypical cases to exclude pulmonary tuberculosis,tumor,and other diseases through lung biopsy.CASE SUMMARY An 18-year-old man presented with recurrent wheezing,cough,and peripheral blood eosinophilia.Chest computed tomography showed pulmonary infiltration.There was a significant increase in eosinophils in bronchoalveolar lavage fluid.There was no history of residing in a parasite-endemic area or any evidence of parasitic infection.Pathologic examination of bronchoalveolar lavage fluid excluded fungal and mycobacterial infections.The patient was receiving medication for comorbid diseases,but there was no temporal correlation between medication use and clinical manifestations,which excluded drug-induced etiology.Histopathological examination of lung biopsy specimen showed no signs of eosinophilic granulomatosis with polyangiitis,IgG4-related diseases,or tumors.The diagnosis of ABPA was considered based on the history of asthma and the significant increase in serum Aspergillus fumigatus-specific immunoglobulin(Ig)E.Eosinophil-related diseases were excluded through pathological biopsy,which showed typical pathological manifestations of ABPA.CONCLUSION The possibility of ABPA should be considered in patients with poorly controlled asthma,especially those with eosinophilia,lung infiltration shadows,or bronchiectasis.Screening for serum IgE,Aspergillus fumigatus-specific IgE and IgG,and alveolar lavage can help avoid misdiagnosis. 展开更多
关键词 Allergic bronchopulmonary aspergillosis ASTHMA ASPERGILLUS Case report
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基于3D残差注意力网络的非接触式心率测量方法
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作者 王宇 戎舟 王苏煜 《国外电子测量技术》 北大核心 2023年第2期53-59,共7页
心率是衡量人体生理状况的重要指标之一,针对传统的信号处理方法容易受到光照变化和运动影响的问题,提出了一种基于3D残差注意力网络的非接触式心率测量方法,该方法对时空网络进行改进,在时空卷积块中嵌入3D卷积注意力模块(3D-CBAM),加... 心率是衡量人体生理状况的重要指标之一,针对传统的信号处理方法容易受到光照变化和运动影响的问题,提出了一种基于3D残差注意力网络的非接触式心率测量方法,该方法对时空网络进行改进,在时空卷积块中嵌入3D卷积注意力模块(3D-CBAM),加强神经网络对视频的通道和空间特征提取,使得模型更加关注生理信号分布强烈的区域,并引入残差结构,在不改变网络深度的同时来提高网络性能。实验结果表明,所提出的方法能实现更加准确的测量,在PURE数据集上的平均绝对误差(MAE)为0.52 bpm,均方根误差(RMSE)为2.42 bpm;在UBFC-rPPG数据集上的MAE为1.17 bpm,RMSE为3.68 bpm,且恢复的远程光电容积脉搏波(remote photoplethysmograph,rPPG)信号与标准生理信号的峰值点位置基本接近。 展开更多
关键词 非接触 心率测量 深度学习 注意力机制
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基于多层人工神经网络的电阻抗成像算法 被引量:5
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作者 戎舟 李若愚 方滔 《国外电子测量技术》 北大核心 2021年第1期80-86,共7页
电阻抗成像(electrical impedance tomography,EIT)作为一种非侵入式的医学成像技术,其重建过程是一个难以计算的病态逆问题。为了保证EIT成像精度并提高运算速度,设计了基于多层神经网络(multilayer artificial neural network,MANN)... 电阻抗成像(electrical impedance tomography,EIT)作为一种非侵入式的医学成像技术,其重建过程是一个难以计算的病态逆问题。为了保证EIT成像精度并提高运算速度,设计了基于多层神经网络(multilayer artificial neural network,MANN)的电阻抗成像逆问题求解方法。该方法分为两个步骤,首先利用EIT正问题得到MANN的训练数据,随后设计MANN网络,经过调参和训练后,该方法能迅速得到精度高的结果。该方法与牛顿法和分裂Bregman方法比较,对仿真数据和实测数据均得到良好的效果。 展开更多
关键词 电阻抗成像 神经网络 逆问题 深度学习
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基于LabVIEW的微电阻抗成像系统的设计 被引量:5
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作者 戎舟 程大元 李若愚 《国外电子测量技术》 2020年第3期98-103,共6页
设计了一个针对微型物理模型的微电阻抗成像系统,对16电极微型物理模型内物体的阻抗分布进行成像。以LabVIEW控制下的数据采集卡为核心,采用16通道多路开关实现激励电流和电压采集通道的切换,向微型模型中注入激励电流,采集电压信号并... 设计了一个针对微型物理模型的微电阻抗成像系统,对16电极微型物理模型内物体的阻抗分布进行成像。以LabVIEW控制下的数据采集卡为核心,采用16通道多路开关实现激励电流和电压采集通道的切换,向微型模型中注入激励电流,采集电压信号并通过前置滤波,两级放大后获得成像所需的数据。系统采集有无物体两种状态的数据进行时差成像,利用敏感矩阵算法实现图像重建,实验结果表明,该系统在激励频率为5、10kHz时可以对不同材质、不同位置的微型模型进行定位,重建图像可以反映出目标物体的相对尺寸和大致形状,保证系统精度的同时简化了硬件结构,为电阻抗成像在医学影像方面的应用提供了重要参考价值。 展开更多
关键词 微电阻抗成像 LABVIEW 16电极微型物理模型 两级放大 敏感矩阵算法
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基于分裂Bregman方法的加权频差电阻抗成像算法 被引量:11
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作者 成民民 戎舟 庞宗强 《国外电子测量技术》 2019年第2期30-35,共6页
加权频差阻尼最小二乘算法引入正则化方法,对病态的敏感矩阵进行修正,克服了背景对成像结果的影响,在背景阻抗不随频率变化时能够反映异物的位置,但当背景的阻抗随着频率的变化而变化时,背景区域的伪影较多,掩盖了异物区域。由于加权频... 加权频差阻尼最小二乘算法引入正则化方法,对病态的敏感矩阵进行修正,克服了背景对成像结果的影响,在背景阻抗不随频率变化时能够反映异物的位置,但当背景的阻抗随着频率的变化而变化时,背景区域的伪影较多,掩盖了异物区域。由于加权频差中,重建两种频率下的阻抗差值具有稀疏性,针对这一特性,引入L1-范数进行约束并采用分裂Bregman方法对其进行优化求解,改善了这一问题。实验结果表明,优化后的加权频差算法能够减少成像中存在的伪影并能进一步提高成像质量。因此,改进的加权频差算法是一种有效的准静态电阻抗成像算法。 展开更多
关键词 加权频差 分裂Bregman方法 稀疏性 L1范数
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男性精神分裂症患者睾酮水平及与认知功能的相关性研究 被引量:3
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作者 周蓉 孙剑 +4 位作者 汪卫华 纪菊英 刘羽 隋云川 张露元 《中国现代医学杂志》 CAS 2019年第23期70-74,共5页
目的探讨男性精神分裂症患者与健康男性血清睾酮水平表达差异及其与患者认知功能的相关性。方法选取中国人民解放军102医院男性首发精神分裂症患者64例为研究组,同期健康体检男性57例为对照组。检测两组研究对象的血清睾酮水平,评估认... 目的探讨男性精神分裂症患者与健康男性血清睾酮水平表达差异及其与患者认知功能的相关性。方法选取中国人民解放军102医院男性首发精神分裂症患者64例为研究组,同期健康体检男性57例为对照组。检测两组研究对象的血清睾酮水平,评估认知功能,对检测结果进行相关性分析。结果研究组血清睾酮水平与对照组比较,差异无统计学意义(P>0.05)。研究组认知功能测试中,数字划销时间、连线A测试结果高于对照组(P <0.05),范畴流畅、空间广度、木块图、连续定步调听觉正确数、连续定步调听觉尝试数低于对照组(P <0.05)。Pearson相关性分析显示,健康男性睾酮水平与数字划销时间、连线A、空间广度、木块图、连续定步调听觉正确数、连续定步调听觉尝试数无相关(P>0.05),男性精神分裂症患者睾酮水平与数字划销时间、连线A呈正相关(P <0.05),与空间广度、木块图、连续定步调听觉正确数、连续定步调听觉尝试数呈负相关(P <0.05),与范畴流畅无相关(P>0.05)。结论首发男性精神分裂症患者血清睾酮水平与健康男性无差异。男性精神分裂症患者血清睾酮水平与空间记忆、注意功能呈负相关,可通过调节患者睾酮水平的方法改善其认知功能。 展开更多
关键词 精神分裂症 睾酮 认知 相关性
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基于WGAN-gp的电阻抗成像后处理算法研究 被引量:1
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作者 李若愚 戎舟 方滔 《国外电子测量技术》 北大核心 2022年第3期124-129,共6页
电阻抗成像是一种非侵入式的医学成像技术,但是常用的重建方法具有一定的伪影。为解决该问题,提出了一种基于Wasserstein距离和梯度惩罚的生成对抗网络的电阻抗成像后处理算法。采用仿真方法设置不同个数、大小、位置和阻抗值的目标物体... 电阻抗成像是一种非侵入式的医学成像技术,但是常用的重建方法具有一定的伪影。为解决该问题,提出了一种基于Wasserstein距离和梯度惩罚的生成对抗网络的电阻抗成像后处理算法。采用仿真方法设置不同个数、大小、位置和阻抗值的目标物体,通过基于有限元法的正问题得到边界电压,建立数据集。然后选取多层神经网络进行初步成像,得到具有误差和伪影的电阻抗分布作为生成对抗网络的输入数据,为了还原优化后阻抗分布的细节,在对抗网路的损失函数中增加了绝对均方误差项,对网络的生成器与判别器进行对抗训练,训练后的生成器用于后处理。仿真数据和实测数据成像结果表明,提出的算法对于目标物体的阻抗值、面积大小和位置的重建更为准确,显著减少了目标物体的伪影。 展开更多
关键词 电阻抗成像 深度学习 生成对抗网络 梯度惩罚
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Hypothalamic-pituitary-adrenal axis hyperactivity accounts for anxiety-and depression-like behaviors in rats perinatally exposed to bisphenol A 被引量:17
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作者 Fang Chen Libin zhou +2 位作者 Yinyang Bai rong zhou Ling Chen 《The Journal of Biomedical Research》 CAS CSCD 2015年第3期250-258,共9页
Accumulating studies have proved that perinatal exposure to environmental dose causes long-term potentiation in anxiety/depression-related behaviors in rats. Hyperactivity of the hypothalamic-pituitary-adrenal (HPA)... Accumulating studies have proved that perinatal exposure to environmental dose causes long-term potentiation in anxiety/depression-related behaviors in rats. Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis is one of the most consistent biological findings in anxiety- and depression-related disorders. The HPA axis is reported to be susceptible to developmental reprogramming. The present study focused on HPA reactivity in postnatal day (PND) 80 male rats exposed perinatally to environmental-dose BPA. When female breeders were orally administered 2 μg/(kg.day) BPA from gestation day 10 to lactation day 7, their offspring (PND 80 BPA-exposed rats) showed obvious anxiety/depression-like behaviors. Notably, significant increase in serum corticosterone and adrenocorticotropin, and corticotropin-releasing hormone mRNA were detected in BPA-exposed rats before or after the mild stressor. Additionally, the level of glucocorticoid receptor mRNA in the hippocampus, but not the hypothalamus, was decreased in BPA-exposed rats. The levels of hippocampal mineralocorticoid receptor mRNA, neuronal nitric oxide synthase and phosphorylated cAMP response element binding protein were increased in BPA-exposed rats. In addition, the testosterone level was in BPA-exposed rats. The results indicate that reprogramming-induced hyperactivity of the HPA axis is an important link between perinatal BPA exposure and persistent potentiation in anxiety and depression. 展开更多
关键词 BPA affective behaviors HPA axis glucocorticoid receptor TESTOSTERONE
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Construction of HBV-specific ribozyme and its recombinant with HDV and their cleavage activity in vitro 被引量:10
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作者 Shu Juan Wen Kai Jun Xiang +2 位作者 Zhen Hua Huang rong zhou Xue Zhong Qi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期377-380,共4页
AIM To construct the recombinant of HDVcDNA and HBV-specific ribozyme gene byrecombinant PCR in order to use HDV as atransporting vector carrying HBV-specificribozyme into liver cells for inhibiting thereplication of ... AIM To construct the recombinant of HDVcDNA and HBV-specific ribozyme gene byrecombinant PCR in order to use HDV as atransporting vector carrying HBV-specificribozyme into liver cells for inhibiting thereplication of HBV.METHODS We separately cloned the ribozyme(RZ)gene and recombinant DVRZ(comprisingHDV cDNA and HBV-specific ribozyme gene)intothe downstream of T7 promoter of pTAdv-Tvector and studied the in vitro cleavage activityof their transcripts(rRZ,rDVRZ)on target RNA(rBVCF)from in vitro transcription of HBV Cgene fragment(BVCF).RESULTS Both the simple(rRZ)and therecombinant ribozyme rDVRZ could efficientlycatalyze the cleavage of target RNA(rBVCF)under different temperatures(37℃,42℃ and55℃)and Mg<sup>2+</sup>concentrations(10 mmol/L,15 mmol/L and 20 mmol/L)and their catalyticactivity tended to increase as the temperaturewas rising.But the activity of rRZ was evidentlyhigher than that of rDVRZ.CONCLUSION The recombinant of HDV cDNAand ribozyme gene had the potential of beingfurther explored and used in gene therapy of HBVinfection. 展开更多
关键词 HEPATITIS B VIRUS HEPATITIS D VIRUS RIBOZYME gene RECOMBINANT DVRZ
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Respiratory Virus Multiplex RT-PCR Assay Sensitivities and Influence Factors in Hospitalized Children with Lower Respiratory Tract Infections 被引量:14
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作者 Jikui Deng Zhuoya Ma +5 位作者 Wenbo Huang Chengrong Li Heping Wang Yuejie Zheng rong zhou Yi-Wei Tang 《Virologica Sinica》 SCIE CAS CSCD 2013年第2期97-102,共6页
Multiplex RT-PCR assays have been widely used tools for detection and differentiation of a panel of respiratory viral pathogens. In this study, we evaluated the Qiagen ResPlex lI V2.0 kit and explored factors influenc... Multiplex RT-PCR assays have been widely used tools for detection and differentiation of a panel of respiratory viral pathogens. In this study, we evaluated the Qiagen ResPlex lI V2.0 kit and explored factors influencing its sensitivity. Nasopharyngeal swab (NPS) specimens were prospectively collected from pediatric inpatients with lower respiratory tract infections at the time of admission in the Shenzhen Children's Hospital from May 2009 to April 2010. Total nucleic acids were extracted using the EZ1 system (Qiagen, Germany) and 17 respiratory viruses and genotypes including influenza A virus (FluA), FluB, parainfluenza virus 1 (PIV1), PIV2, PIV3, PIV4, respiratory syncytial virus (RSV), human metapneumovirus (hMPV), rhinoviruses (RhV), enteroviruses (EnV), human bocaviruses (hBoV), adenoviruses (AdV), four coronaviruses (229E, OC43, NL63 and HKU1), and FluA 2009 pandemic H1NI(H1NI-p) were detected and identified by the ResPlex II kit. In parallel, 16 real-time TaqMan quantitative RT-PCR assays were used to quantitatively detect each virus except for RhV. Influenza and parainfluenza viral cultures were also performed. Among the total 438 NPS specimens collected during the study period, one or more viral pathogens were detected in 274 (62.6%) and 201(45.9%) specimens by monoplex TaqMan RT-PCR and multiplex ResPlex, respectively. When results from monoplex PCR or cell culture were used as the reference standard, the multiplex PCR possessed specificities of 92.9-100.0%. The sensitivity of multiplex PCR for PIV3, hMPV, PIV1 and BoV were 73.1%, 70%, 66.7% and 55.6%, respectively, while low sensitivities (11.1%-40.0%) were observed for FluA, EnV, OC43, RSV and H1N1. Among the seven viruses/genotypes detected with higher frequencies, multiplex PCR sensitivities were correlated significantly with viral loads determined by the TaqMan RT-PCR in FluA, H 1N 1-p and RSV (p=0.011-0.000) The Qiagen ResPlex II multiplex RT-PCR kit possesses excellent specificity for simultaneous detection of 17 viral pathogens in NPS specimens in pediatric inpatients at the time of admission. The sensitivity of multiplex RT-PCR was influenced by viral loads, specimen process methods, primer and probe design and amplification condition. 展开更多
关键词 Multiplex RT-PCR Respiratory viral loads Cell culture Lower respiratory tract infection
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Laboratory testing and molecular analysis of the resistance of wild and cultivated soybeans to cotton bollworm, Helicoverpa armigera(Hübner) 被引量:6
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作者 Xiaoyi Wang Haifeng Chen +10 位作者 Aihua Sha rong zhou Zhihui Shang Xiaojuan Zhang Chanjuan Zhang Limiao Chen Qingnan Hao Zhonglu Yang Dezhen Qiu Shuilian Chen Xinan zhou 《The Crop Journal》 SCIE CAS CSCD 2015年第1期19-28,共10页
Identifying a superior soybean variety with high defoliator resistance is important to avoid yield loss. Cotton bollworm(Helicoverpa armigera Hübner) is one of the major defoliators of soybean(Glycine max [L.] Me... Identifying a superior soybean variety with high defoliator resistance is important to avoid yield loss. Cotton bollworm(Helicoverpa armigera Hübner) is one of the major defoliators of soybean(Glycine max [L.] Merr.) worldwide. In this study, we evaluated the effect of H. armigera larvae on ED059, a wild soybean(Glycine soja Sieb. et Zucc.), and three cultivated soybean varieties: Tianlong 2, PI 535807, and PI 533604, in choice and no-choice assays. The percentage of ED059 leaflets consumed by H. armigera was lower than that of the three cultivated soybeans. Larvae that fed on ED059 exhibited low weight gain and high mortality rate.Waldbauer nutritional indices suggested that ED059 reduced the growth, consumption, and frass production of H. armigera larvae. Larvae that fed on ED059 showed lower efficiency of conversion of ingested and of digested food than those that fed on Tianlong 2 and PI 533604.However, they showed statistically similar consumption index and approximate digestibility compared with those fed on the three cultivated soybeans. Quantitative real-time PCR analysis revealed that 24 h after insect attack, ED059 had higher transcript levels of Kunitz trypsin inhibitor 3, Cysteine proteinase inhibitor 2, and Nerolidol synthase 1 but a lower transcript level of Pathogenesis-related protein 1 than Tianlong 2. The gene expression results were consistent with the presence of higher levels of jasmonic acid(JA) and transcript levels of the JA biosynthesis enzyme allene oxide cyclase 3 in ED059 than in Tianlong 2. Our findings indicate that ED059 is a superior soybean line with strong insect resistance that may be mediated via the JA pathway. 展开更多
关键词 SOYBEAN DEFOLIATION DEFOLIATOR RESISTANCE REAL-TIME PCR
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Comprehensive identification and analyses of the Hsf gene family in the whole-genome of three Apiaceae species 被引量:6
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作者 Qiaoying Pei Tong Yu +9 位作者 TongWu Qihang Yang Ke Gong rong zhou Chunlin Cui Ying Yu Wei Zhao Xi Kang Rui Cao Xiaoming Song 《Horticultural Plant Journal》 SCIE CSCD 2021年第5期457-468,共12页
Apiaceae is a major family from Apiales and includes many important vegetable and medicinal crops.Heat shock transcription factors(Hsf)play important roles in heat tolerance during plant development.Here,we conducted ... Apiaceae is a major family from Apiales and includes many important vegetable and medicinal crops.Heat shock transcription factors(Hsf)play important roles in heat tolerance during plant development.Here,we conducted systematic analyses of the Hsf gene family in three Apiaceae species,including 17 Apium graveolens(celery),32 Coriandrum sativum(coriander),and 14 Daucus carota(carrot).A total of 73 Hsf genes were identified in three representative species,including Arabidopsis thaliana,Vitis vinifera,and Lactuca sativa.Whole-genome duplication played important roles in the Hsf gene family’s expansion within Apiaceae.Interestingly,we found that coriander had more Hsf genes than celery and carrot due to greater expansion and fewer losses.Twenty-seven branches of the phylogenetic tree underwent considerable positive selection in these Apiaceae species.We also explored the expression patterns of Hsf genes in three plant organs.Collectively,this study will serve as a rich gene resource for exploring the molecular mechanisms of heat tolerance.Additionally,this is the first study to report on the Hsf gene family in Apiaceae;thus,our research will provide guidance for future comparative and functional genomic studies on the Hsf gene family and others in Apiaceae. 展开更多
关键词 Hsf gene family Gene duplication and loss Expression pattern Apiaceae
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猪耳成纤维细胞转录组异质性及对核移植胚胎发育的潜在影响
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作者 周俊 赵成成 +4 位作者 吴霄 石俊松 周荣 吴珍芳 李紫聪 《遗传》 CAS CSCD 北大核心 2020年第9期898-915,共18页
同一来源的供体细胞之间存在异质性。许多研究已经表明体细胞核移植(somatic cell nuclear transfer,SCNT)效率与供体细胞有关。然而,鲜有在单细胞水平分析供体细胞异质性对核移植效率的潜在影响。本研究利用单细胞转录组测序技术对同... 同一来源的供体细胞之间存在异质性。许多研究已经表明体细胞核移植(somatic cell nuclear transfer,SCNT)效率与供体细胞有关。然而,鲜有在单细胞水平分析供体细胞异质性对核移植效率的潜在影响。本研究利用单细胞转录组测序技术对同一来源且随机挑选的52个猪耳组织成纤维细胞进行测序分析。结果表明有48个单细胞的基因表达模式相似,4个单细胞(编号为D11_1、D12_1、DW61_2和DW99_2)的基因表达模式与其他单细胞存在较大的差异,并且不存在基因表达模式完全相同的两个单细胞。以基因表达模式相似的48个单细胞作为对照,进一步分析了单细胞D11_1、D12_1、DW61_2和DW99_2的差异基因表达模式:首先利用R语言筛选4个单细胞的差异表达基因,并对前50差异表达基因进行汇总;然后对差异表达基因进行GO富集分析和KEGG通路分析。富集分析发现差异表达基因的主要分子功能包括能量代谢、蛋白质代谢和细胞对刺激的反应等;主要通路包括KEGG中富集的与细胞周期、细胞代谢、DNA复制相关的通路。根据以上研究结果并结合SCNT研究进展讨论了4个单细胞的差异基因表达模式对核移植胚胎发育效率的潜在影响。本研究揭示了猪耳组织成纤维细胞的转录组异质性,并提供了分析精英供体细胞的一种有效方法,为提高克隆效率带来新的思路。 展开更多
关键词 体细胞核移植 供体细胞 异质性 单细胞测序
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