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Oxide-aperture-dependent output characteristics of circularly symmetric VCSEL structure

Chinese Physics B 2020年第2期29卷 275-281页

作者： wen-Yuan Liao jian Li Chuan-Chuan Li xiao-feng guo wen-Tao guo Wei-Hua liu yang-Jie Zhang Xin Wei Man-Qing Tan State Key Laboratory of Integrated Optoelectronic Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China Laboratory of Nano-photoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

The influence ot oxidation aperture on the output characteristics ot the circularly symmetric vertical-cavity-surtaceemitting laser(VCSEL) structure is *** do so,VCSELs with different oxide aperture sizes are simulated by the finite-difference time-domain(FDTD) *** relationships among the field distribution of mode superposition,mode wavelength,output spectra,and far-field divergence with different oxide apertures are ***,VCSELs respectively with oxide aperture sizes of 2.7 μm,4.4 μm,5.9 μm,7 μm,8 μm,9 μm,and 18.7 μm are fabricated and *** maximum output power increases from 2.4 mW to 5.7 mW with oxide aperture increasing from 5.9 μm to 9 μ***,the wavelength tuning rate decreases from 0.93 nm/mA to 0.375 nm/mA when the oxide aperture increases from 2.7 μm to 9 μ*** thermal resistance decreases from 2.815℃/mW to 1.015℃/mW when the oxide aperture increases from 4.4 μm to 18.7μ*** is demonstrated theoretically and experimentally that the wavelength spacing between adjacent modes increases with the augment of the injection current and the spacing becomes smaller with the oxide aperture *** it can be reported that the aperture size can effectively reduce the mode overlaying but at the cost of the power decreasing and the wavelength tuning rate and thermal resistance increasing.

关键词： finite-difference time-domain(FDTD) vertical-cavity-surface-emitting laser(VCSEL) oxide aperture wavelength spacing

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Sensitivity of heavy-ion-induced single event burnout in SiC MOSFET

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Chinese Physics B 2022年第1期31卷 652-657页

作者： hong Zhang hong-Xia guo feng-Qi Zhang xiao-Yu Pan Yi-Tian liu Zhao-Qiao gu An-An Ju xiao-Ping Ouyang School of Material Science and Engineering Xiangtan UniversityXiangtan 411105China Northwest Institute of Nuclear Technology Xi'an 710024China

The energy deposition and electrothermal behavior of SiC metal-oxide-semiconductor field-effect transistor(MOSFET)under heavy ion radiation are investigated based on Monte Carlo method and TCAD numerical *** Monte Carlo simulation results show that the density of heavy ion-induced energy deposition is the largest in the center of the heavy ion *** time for energy deposition in SiC is on the order of *** TCAD is used to simulate the single event burnout(SEB)sensitivity of SiC MOSFET at four representative incident positions and four incident *** heavy ions strike vertically from SiC MOSFET source electrode,the SiC MOSFET has the shortest SEB time and the lowest SEB voltage with respect to direct strike from the epitaxial layer,strike from the channel,and strike from the body diode *** current and strong electric field simultaneously appear in the local area of SiC MOSFET,resulting in excessive power dissipation,further leading to excessive high lattice *** gate-source junction area and the substrate-epitaxial layer junction area are both the regions where the SiC lattice temperature first reaches the SEB critical *** the SEB simulation of SiC MOSFET at different incident depths,when the incident depth does not exceed the device's epitaxial layer,the heavy-ion-induced charge deposition is not enough to make lattice temperature reach the SEB critical temperature.

关键词： SiC MOSFET Monte Carlo method TCAD single event burnout lattice temperature

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量化信道边信息下的对称容量研究

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北京邮电大学学报 2008年第4期31卷 86-89页

作者：刘晓峰杨鸿文古建北京邮电大学电信工程学院北京100876

研究了慢变平衰落瑞利信道下,信道信息的量化反馈对系统对称容量的影响,给出了不同功率限制下的最优量化方案.在无功率控制时,问题简化为单一变量的极值问题;在有功率限制时,最优的功率控制方法是脉冲型功率控制,然后用迭代的方式求解... 详细信息

研究了慢变平衰落瑞利信道下,信道信息的量化反馈对系统对称容量的影响,给出了不同功率限制下的最优量化方案.在无功率控制时,问题简化为单一变量的极值问题;在有功率限制时,最优的功率控制方法是脉冲型功率控制,然后用迭代的方式求解最优边界点.数值结果表明,4 bit量化与无限量化性能十分接近;与无反馈相比,采用有限比特的量化反馈能获得明显的容量增益.与高斯输入时不同,在有限星座输入时,发送功率控制所起的作用更大,在相同量化级数下,有功率分配比无功率分配能使容量大致提高10%.

关键词：对称容量信道状态信息量化

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Antitumor effect of matrine in human hepatoma G2 cells by inducing apoptosis and autophagy

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World Journal of Gastroenterology 2010年第34期16卷 4281-4290页

作者： Zhang, Jun-Qiang Li, Yu-Min liu, Tao He, wen-Ting Chen, Ying-Tai Chen, xiao-Hui Li, Xun Zhou, wen-Ce Yi, jian-feng Ren, Zhi-jian Lanzhou Univ Hosp 2 Lanzhou 730030 Gansu Province Peoples R China Gansu Prov Key Lab Digest Syst Tumors Lanzhou 730030 Gansu Province Peoples R China Lanzhou Univ Hosp 1 Dept Gen Surg Lanzhou 730000 Gansu Province Peoples R China Lanzhou Univ Clin Med Sch 1 Lanzhou 730000 Gansu Province Peoples R China

AIM: To study the antitumor effect of matrine in human hepatoma G2 (HepG2) cells and its molecular mechanism involved in antineoplastic activities. METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect viability of HepG2 cells. The effect of matrine on cell cycle was detected by flow cytometry. Annexin-V-FITC/PI double staining assay was used to detect cellular apoptosis. Cellular morphological changes were observed under an inverted phase contrast microscope. Transmission electron microscopy was performed to further examine ultrastructural structure of the cells treatedwith matrine. Monodansylcadaverine (MDC) staining was used to detect autophagy. Whether autophagy is blocked by 3-methyladenine (3-MA), an autophagy inhibitor, was evaluated. Expression levels of Bax and Beclin 1 in HepG2 cells were measured by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR).RESULTS: Matrine signif icantly inhibited the proliferation of HepG2 cells in a dose- and time-dependent manner, and induced G1-phase cell cycle arrest and apoptosis of HepG2 cells in a dose-dependent manner. The total apoptosis rate was 0.14% for HepG2 cells not treated with matrine. In contrast, the apoptosis rate was 28.91%, 34.36% and 38.80%, respectively, for HepG2 cells treated with matrine at the concentration of 0.5, 1.0 and 2.0 mg/mL. The remarkable morphological changes were observed under an inverted phase contrast microscope. Abundant cytoplasmic vacuoles with varying sizes were observed in HepG2 cells treated with matrine. Furthermore, vacuolization in cytoplasm progressively became larger and denser when the concentration of matrine was increased. Electron microscopy demonstrated formation of abundant autophagic vacuoles in HepG2 cells after matrine treatment. When the specif ic autophagic inhibitor, 3-MA, was applied, the number of autophagic vacuoles greatly decreased. MDC staining showed that the fluorescent density wa

关键词： Matrine Autophagy Apoptosis Bax Beclin 1 Hepatocellular carcinoma

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Novel deletion mutations of the PIH1D3 gene in an infertile young man with primary ciliary dyskinesia and his cousin with Kartagener’s syndrome

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Asian Journal of Andrology 2021年第3期23卷 330-332页

作者： Chuan Huang Na-Chuan liu xiao-Bo Wang Ben-hong gu jian-Xiong Zhang Li-Zhang Zheng Li Department of Andrology Center for Men's HealthShanghaiChina Department of ART Institute of Urologic Medical CenterShanghai General HospitalShanghaiKey Lab of Reproductive MedicineShanghai Jiao Tong UniversityShanghai 200080China The Human Sperm Bank Reproductive and Genetic Hospital of CITIC-XiangyaChangsha 410000China Department of Urology Tongren HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai 200080China.

Dear Editor,Male infertility is defined as the inability to achieve pregnancy in a fertile female partner even after 12 months of unprotected *** humans,it accounts for 40%-50%of cases of infertility,1 and it occurs most often due to problems with sperm production or sperm *** infertility is commonly due to deficiencies in semen,and semen quality is used as a surrogate measure of male *** ciliary dyskinesia(PCD)is a rare cause of male infertility.2,3 It is an autosomal recessive genetic condition that causes abnormal function of *** are microscopic finger-like projections on the surface of the cells.

关键词： partner protected cilia

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A QTC-based signal readout for position-sensitive multi-output detectors

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Nuclear Science and Techniques 2016年第5期27卷 208-214页

作者： Wei Zhou Zhi-Ming Zhang Dao-Wu Li Pei-Lin Wang Bao-Tong feng Xian-Chao Huang Ting-Ting Hu xiao-Hui Li Yan Chen Ying-Jie Wang Yan-Tao liu Yi-wen Zhang Shi-feng Sun xiao-Yue gu Ming-Jie yang Xiong xiao Long Wei Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Beijing Engineering Research Center of Radiographic Techniques and Equipment Beijing 100049 China University of Chinese Academy of Sciences Beijing 100049

A new signal readout method for position-sensitive multi-output detectors,such as those in high-energy spectroscopy measurement and nuclear imaging,was developed by combining the charge division circuit,summing circuit and charge-to-time conversion(QTC) *** 64 outputs of a Hamamatsu H8500 position-sensitive photomultiplier tube were processed,and three digital pulses were *** widths of digital pulses were determined using the time-to-digital converter in an field programmable gate *** energy and position information of incident y-rays is estimated based on the proportionality between the width of digital pulses and input charge created by y-photons.A prototype was built using discrete components and tested,and the energy and position resolutions were improved compared with that obtained with standard *** method greatly simplifies the front-end electronics and the digital *** enables a compact electronics system and an easy integration into an ASIC.

关键词：输出信号位置灵敏探测器多输出读出位置灵敏光电倍增管现场可编程门阵列时间-数字转换器位置敏感探测器

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Vitellaria paradoxa nutshells from seven sub-Saharan countries as potential herbal medicines for treating diabetes based on chemical compositions, HPLC fingerprints and bioactivity evaluation

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Chinese Journal of Natural Medicines 2019年第6期17卷 446-460页

作者： LI Da xiao jian-Qi liu wen-Yuan ZHANG Chao-feng AKIHISA Toshihiro ABE Masahiko MASTERS Eliot-T. ZHAI Wei-Wei feng feng ZHANG Jie jiangsu Food and Pharmaceutical Science College Huai’an 223003China Department of Pharmaceutical Analysis China Pharmaceutical UniversityNanjing 210009China Research Institute for Science and Technology Tokyo University of ScienceChiba 278-8510Japan World Agroforestry Centre(ICRAF) Nelson Marlbolough Institute of Technology(NMIT)Nelson 7010New Zealand School of Traditional Chinese Pharmacy China Pharmaceutical UniversityNanjing 211198China Key Laboratory of Biomedical Functional Materials China Pharmaceutical UniversityNanjing 211198China

The aim of the study was to determine the feasibility of the Vitellaria paradoxa nutshell as a new medicinal resource for treating diabetes. A total of forty-one compounds were identified by HPLC-DAD-Q-TOF-MS and phytochemical methods in V. paradoxa nutshell methanol extract. Based on HPLC fingerprints, four characteristic constituents were quantified and the origin of twenty-eight V. paradoxa nutshells from seven sub-Saharan countries was compared, which were classified into three groups with chemometric method. Twenty-eight samples contained high total phenolic content, and exhibited moderate-higher antioxidant activity and strong α-glucosidase inhibitory activity. Furthermore, all fractions and isolated compounds were evaluated for their antioxidant and α-glucosidase inhibitory activities, and α-glucosidase inhibitory action mechanism of four characteristic constituents including protocatechuic acid, 3, 5, 7-trihydroxycoumarin,(2 R, 3 R)-(+)-taxifolin and quercetin was investigated via molecular docking method, which were all stabilized by hydrogen bonds with α-glucosidase. The study provided an effective approach to waste utilization of V. paradoxa nutshell, which would help to resolve waste environmental pollution and provide a basis for developing potential herbal resource for treating diabetes.

关键词： Vitellaria paradoxa HPLC fingerprints Antioxidant activity α-Glucosidase inhibitory activity Molecular docking

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Simple nonlinear model for the relationship between maize yield and cumulative water amount

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Journal of Integrative Agriculture 2017年第4期16卷 858-866页

作者： liu Cheng SUN Bao-cheng TANG Huai-jun WANG Tian-yu LI Yu ZHANG Deng-feng XIE xiao-qing SHI Yun-su SONG Yan-chun yang xiao-hong LI jian-sheng Maize Research Center China Agricultural University Institute of Grain Crops Xinjiang Academy of Agricultural Sciences Institute of Crop Sciences Chinese Academy of Agricultural Sciences

Both the additive and multiplicative models of crop yield and water supply are polynomial equations, and the number of parameters increases linearly when the growing period is specified. However, interactions among multiple parameters occasionally lead to unreasonable estimations of certain parameters, which were water sensitivity coefficients but with negative value. Additionally, evapotranspiration must be measured as a model input. To facilitate the application of these models and overcome the aforementioned shortcomings, a simple model with only three parameters was derived in this paper based on certain general quantitative relations of crop yield （Y） and water supply （W）. The new model, Y/Y-W＊/（W＊＋w＊）, fits an S or a saturated curve of crop yield with the cumulative amount of water. Three parameters are related to biological factors： the yield potential （Y＊）, the water requirement to achieve half of the yield potential （half-yield water requirement, wh）, and the water sensitivity coefficient （k）. The model was validated with data from 24 maize lines obtained in the present study and 17 maize hybrids published by other authors. The results showed that the model was well fit to the data, and the normal root of the mean square error （NRMSE） values were 2.8 to 17.8% （average 7.2%） for the 24 maize lines and 2.7 to 12.7% （average 7.4%） for the 17 maize varieties. According to the present model, the maize water-sensitive stages in descending order were pollen shedding and silking, tasselling, jointing, initial grain filling, germination, middle grain filling, late grain filling, and end of grain filling. This sequence was consistent with actual observations in the maize field. The present model may be easily used to analyse the water use efficiency and drought tolerance of maize at specific stages.

关键词： yield water model maize water sensitivity drought tolerance

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Genetic dissection of crown root traits and their relationships with aboveground agronomic traits in maize

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Journal of Integrative Agriculture 2023年第11期22卷 3394-3407页

作者： SHA xiao-qian guAN hong-hui ZHOU Yu-qian SU Er-hu guO jian LI Yong-xiang ZHANG Deng-feng liu Xu-yang HE guan-hua LI Yu WANG Tian-yu ZOU Hua-wen LI Chun-hui College of Agriculture Yangtze UniversityJingzhou 434000P.R.China State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Crops Gansu Academy of Agricultural SciencesLanzhou 730070P.R.China Institute of Maize Research Inner Mongolia Academy of Agricultural&Animal Husbandry SciencesHohhot 010031P.R.China

The crown root system is the most important root component in maize at both the vegetative and reproductive stages. However, the genetic basis of maize crown root traits(CRT) is still unclear, and the relationship between CRT and aboveground agronomic traits in maize is poorly understood. In this study, an association panel including 531 elite maize inbred lines was planted to phenotype the CRT and aboveground agronomic traits in different field environments. We found that root traits were significantly and positively correlated with most aboveground agronomic traits, including flowering time, plant architecture and grain yield. Using a genome-wide association study(GWAS)coupled with resequencing, a total of 115 associated loci and 22 high-confidence candidate genes were identified for CRT. Approximately one-third of the genetic variation in crown root was co-located with 46 QTLs derived from flowering and plant architecture. Furthermore, 103 (89.6%) of 115 crown root loci were located within known domestication-and/or improvement-selective sweeps, suggesting that crown roots might experience indirect selection in maize during domestication and improvement. Furthermore, the expression of Zm00001d036901, a high-confidence candidate gene, may contribute to the phenotypic variation in maize crown roots, and Zm00001d036901 was selected during the domestication and improvement of maize. This study promotes our understanding of the genetic basis of root architecture and provides resources for genomics-enabled improvements in maize root architecture.

关键词： maize root aboveground agronomic traits GWAS candidate genes

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A Cysteinyl-tRNA Synthetase Mutation Causes Novel Autosomal-Dominant Inheritance of a Parkinsonism/Spinocerebellar-Ataxia Complex

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Neuroscience Bulletin 2024年第10期40卷 1489-1501页

作者： Han-Kui liu hong-Lin Hao Hui You feng feng Xiu-hong Qi xiao-Yan Huang Bo Hou Chang-Geng Tian Han Wang Huan-Ming yang jian Wang Rui Wu Hui Fang jiang-Ning Zhou jian-guo Zhang Zhen-Xin Zhang BGI Genomics and BGI Research Shenzhen 518083China Department of Neurology Clinical Epidemiology UnitPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei 230026China Department of Radiology Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Department of Pathology Beijing Key Laboratory of Biomarker Research and Transformation for Neurodegenerative DiseasesPeking University Third HospitalSchool of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Anhui Provincial Children's Hospital Children's Hospital of Fudan UniversityHefei 230051China Hebei Industrial Technology Research Institute of Genomics in Maternal and Child Health Clin LabBGI GenomicsShijiazhuang 050011China Institute of Brain Science The First Affliated Hospital of Anhui Medical UniversityHefei 230022China

This study aimed to identify possible pathogenic genes in a 90-member family with a rare combination of multiple neurodegenerative disease phenotypes,which has not been depicted by the known neurodegenerative *** performed physical and neurological examinations with International Rating Scales to assess signs of ataxia,Parkinsonism,and cognitive function,as well as brain magnetic resonance imaging scans with seven *** searched for co-segregations of abnormal repeat-expansion loci,pathogenic variants in known spinocerebellar ataxiarelated genes,and novel rare mutations via whole-genome sequencing and linkage analysis.A rare co-segregating missense mutation in the CARS gene was validated by Sanger sequencing and the aminoacylation activity of mutant CARS was measured by spectrophotometric *** pedigree presented novel late-onset core characteristics including cerebellar ataxia,Parkinsonism,and pyramidal signs in all nine affected *** magnetic resonance imaging showed cerebellar/pons atrophy,pontine-midline linear hyperintensity,decreased rCBF in the bilateral basal ganglia and cerebellar dentate nucleus,and hypo-intensities of the cerebellar dentate nuclei,basal ganglia,mesencephalic red nuclei,and substantia nigra,all of which suggested ***-genome sequencing identified a novel pathogenic heterozygous mutation(E795V)in the CARS gene,meanwhile,exhibited none of the known repeat-expansions or point mutations in pathogenic ***,this CARS mutation causes a 20%decrease in aminoacylation activity to charge tRNA^(Cys) with L-cysteine in protein synthesis compared with that of the wild *** family members carrying a heterozygous mutation CARS(E795V)had the same clinical manifestations and neuropathological changes of Parkinsonism and *** findings identify novel pathogenesis of Parkinsonismspinocerebellar ataxia and provide insights into its genetic architecture.

关键词： Parkinsonism Spinocerebellar ataxia CARS gene

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