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PLZF^posc-KIT^pos-delineated A1-A4-differentiating spermatogonia by subset and stage detection upon Bouin fixation

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Asian Journal of Andrology 2019年第3期21卷 309-318页

作者： Rui-ling Tang li-qing Fan Institute of Reproduction and Stem Cell Engineering School of Basic Medicine Science Central South University Changsha 410078 China

While hallmarks of rodent spermatogonia stem cell biomarkers' heterogeneity have recently been identified, their stage and subset distributions remain unclear. Furthermore, it is currently difficult to accurately identify subset-specific SSC marker distributions due to the poor nuclear morphological characteristics associated with fixation in 4% paraformaldehyde. In the present study, testicular cross-sections and whole-mount samples were Bouin fixed to optimize nuclear resolution and visualized by immunohistochemistry (IHC) and immunofluorescence (IF). The results identified an expression pattern of PLZFhighc-KITpos in A1 spermatogonia, while A2–A4-differentiating spermatogonia were PLZFlowc-KITpos. Additionally, this procedure was used to examine asymmetrically expressing GFRA1 and PLZF clones, asymmetric Apr and false clones were distinguished based on the presence or absence of TEX14, a molecular maker of intercellular bridges, despite having identical nuclear morphology and intercellular distances that were litates the accurate identification of spermatogonium subsets based on their molecular profiles and is capable of distinguishing asymmetric and false clones. Therefore, the findings presented herein will facilitate further morphological and functional analysis studies and provide further insight into spermatogonium subtypes.

关键词： asymmetric division cellular homolog of feline sarcoma viral oncogene v-kit false clones glial cell line-derived neurotrophic factor receptor alpha 1 promyelocytic leukemia zinc finger spermatogonia stem cell

Remaining Useful life Prediction of Rolling Element Bearings Based on Different Degradation Stages and Particle Filter

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第3期36卷 432-441页

作者： li qing MA Bo liU Jiameng Beijing Key Laboratory of High?End Mechanical Equipment Health Monitoring and Self?recovery Beijing University of Chemical Technology

A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle *** model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation *** remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status *** late operating trend is predicted by the use of the particle filter *** rolling bearing full life experimental data validate the proposed ***,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability.

关键词： different life stages of state space model remaining useful life prediction of rolling element bearing particle filter

Expedient Synthesis of Ketones via N-Heterocyclic Carbene/ Nickel-Catalyzed Redox-Economical Coupling of Alcohols and Alkynest

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Chinese Journal of Chemistry 2020年第10期38卷 1035-1039页

作者： Yu-qing li Feng li Shi-liang Shi State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China

Summary of main observation and conclusion An A/-heterocyclic carbene/nickel-catalyzed direct coupling of alcohols and internal alkynes to form a-branched ketones has been *** methodology provides a new approach to afford branched ketones,which are difficult to access through the hydroacylation of simple internal alkenes with *** redox-neutral and redox-economical coupling is free from any oxidative or reductive additives as well as stoichiometric *** reactions convert both benzylic and aliphatic alcohols and alkynes,two basic feedstock chemicals,into various a-branched ketones in a single chemical step.

关键词： alcohols coupling aldehydes

Prevalence of irritable bowel syndrome in Chinese college and university students assessed using Rome Ⅲ criteria

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World Journal of Gastroenterology 2010年第33期16卷 4221-4226页

作者： Yan-Yan Dong Xiu-li Zuo Chang-qing li Yan-Bo Yu QiuJie Zhao Yan-qing li Department of Gastroenterology Qilu HospitalShandong UniversityJinan 250012Shandong ProvinceChina

AIM:To estimate the prevalence of irritable bowel syndrome(IBS)in college and university students of North China and certain related factors for ***:A total of 2500 students from Shandong University in North China were asked in February-March 2009 to complete questionnaires,including the Rome Ⅲquestionnaire,hospital anxiety and depression scale,and IBS-quality of life questionnaire(IBS-QOL).RESULTS:Among the 2126 students with complete data,the prevalence of IBS was 7.85%according to the RomeⅢcriteria,with a female/male ratio of 1.78:*** students had the IBS-constipation subtype (36.5%),followed by IBS-diarrhea subtype(31.1%)and IBS-mixed subtype(23.9%).The students with IBS had a higher anxiety and depression score than those without *** exercise level and anxiety indicated a high risk for *** mean score of IBS patients was 74.2± 4.242 on the ***:The prevalence of IBS is 7.85%in Chinese college and university students according to the RomeⅢ*** exercise level and anxiety may be the risk factors for IBS.

关键词： Irritable bowel syndrome Prevalence Col- lege and university students

基于IWOA-LSTM算法的预应力钢筋混凝土梁损伤识别

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江苏大学学报（自然科学版） 2025年第1期46卷 105-112,119页

作者：范旭红章立栋杨帆李青郁董凯江苏大学土木工程与力学学院江苏镇江212013 河南省公路工程局集团第二公路工程有限公司河南郑州450015 中国葛洲坝集团第二工程有限公司四川成都610091

为准确识别桥梁结构的损伤程度,制作了桥梁的关键构件——预应力钢筋混凝土梁,进行三点弯曲加载试验.收集了损伤破坏全过程的声发射(AE)信号,通过AE信号参数分析,将梁的损伤破坏过程划分为4个典型阶段.构建了长短时记忆神经网络(LSTM)模... 详细信息

为准确识别桥梁结构的损伤程度,制作了桥梁的关键构件——预应力钢筋混凝土梁,进行三点弯曲加载试验.收集了损伤破坏全过程的声发射(AE)信号,通过AE信号参数分析,将梁的损伤破坏过程划分为4个典型阶段.构建了长短时记忆神经网络(LSTM)模型,根据经验设置LSTM模型的超参数容易导致网络陷入局部最优而影响了分类结果,提出采用Sine混沌映射和自适应权重来改进鲸鱼优化算法(WOA),对LSTM进行超参数寻优.设计了IWOA-LSTM算法模型,训练识别试验梁各损伤阶段的AE信号特征参数.定型网络结构,并识别同种工况下其他梁的AE信号.结果表明:IWOA-LSTM算法模型识别准确率均超过或接近92%,相较于普通LSTM模型,IWOA-LSTM模型识别准确率提高了约7%.

关键词：预应力钢筋混凝土梁声发射损伤识别长短时记忆神经网络改进的鲸鱼优化算法

Comparison of Three Methods for Determination of Root Hydraulic Conductivity of Maize(Zea mays L.)Root System

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Agricultural Sciences in China 2010年第10期9卷 1438-1447页

作者： li qing-ming liU Bin-bin State Key Laboratory of Crop Biology Shandong Agricultural University Tai'an 271018 P.R. China Key Laboratory of Horticultural Crop Biology Ministry of Agriculture/Shandong Agricultural University Tai'an 271018 P.R.China

Three techniques of root pressure probe, pressure chamber and high pressure flow meter were used to measure the hydraulic conductivities （Lpr） of whole root systems of young maize （Zea mays L.） seedlings grown hydroponically under either drought or normal water conditions. Compared to normal water conditions, drought stress simulated by polyethylene glycol 6 000 （osmotic potential =-0.2 MPa） reduced Lpr in the root system by over 50%. It indicated that water permeability in the roots decreased significantly when plants suffered from water shortages. Moreover, there was no significant difference （P〈 0.05） on the Lpr values in the root systems developed under a given water stress regime among the three techniques used. Therefore, all three methods are acceptable to study the hydraulic conductivity of maize seedling root systems. We have also highlighted some of the technical limitations of each method. It can be inferred that the root pressure probe is preferable for young maize seedlings because it is subtle and has the additional ability to determine solute transport properties, but the method is time consuming. Other advantages and disadvantages of each technique are discussed in order to acquaint researchers with basic information that could contribute to their choice of an appropriate technique for future studies.

关键词： hydraulic conductivity Zea mays L. root pressure probe pressure chamber high pressure flow meter

Detection of Foreign Bodies and Bubble Defects in Tire Radiography Images Based on Total Variation and Edge Detection

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Chinese Physics Letters 2013年第8期30卷 78-82页

作者： ZHANG Yan li Tao li qing-ling College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061

We present the analysis and decomposition of tire radiography images by combining the total variation,curvelet transform based image enhancement,and Canny edge detection to detect foreign bodies and bubble defects in *** on the feature of total variation that images can be decomposed as texture parts and cartoon parts,we decompose the tire radiography image and select the cartoon part for defect detection since the textures are segmented and defect information is *** edges of the image are enhanced by modifying the curvelet coefficients before further edge detection ***,a Canny edge detection operator is used to detect the defects in which the eight-neighborhood bilinear interpolation non-maximum suppression method is employed to improve the detection *** our experiments,the Sobel operator and state-of-the-art methods such as the LoG operator and Canny edge detection algorithms are employed for comparison,and the experimental results are discussed *** experimental results indicate that foreign bodies and bubbles in tires can be detected and located accurately by our proposed method.

关键词： Image image neighborhood

Propofol and remifentanil at moderate and high concentrations affect proliferation and differentiation of neural stem/progenitor cells

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Neural Regeneration Research 2014年第22期9卷 2002-2007页

作者： qing li Jiang Lu Xianyu Wang Department of Anesthesiology Taihe HospitalHubei University of Medicine Anesthesiology Research Institude Taihe HospitalHubei University of Medicine

Propofol and remifentanil alter intracellular Ca^2＋ concentration （[Ca^2＋]i） in neural stem/progen-itor cells by activating γ-aminobutyric acid type A receptors and by reducing testosterone levels. However, whether this process affects neural stem/progenitor cell proliferation and differenti-ation remains unknown. In the present study, we applied propofol and remifentanil, alone or in combination, at low, moderate or high concentrations （1, 2–2.5 and 4–5 times the clinically effective blood drug concentration）, to neural stem/progenitor cells from the hippocampi of newborn rat pups. Low concentrations of propofol, remifentanil or both had no noticeable effect on cell proliferation or differentiation; however, moderate and high concentrations of propofol and/or remifentanil markedly suppressed neural stem/progenitor cell proliferation and differen-tiation, and induced a decrease in [Ca^2＋]i during the initial stage of neural stem/progenitor cell differentiation. We therefore propose that propofol and remifentanil interfere with the prolifer-ation and differentiation of neural stem/progenitor cells by altering [Ca^2＋]i. Our ifndings suggest that propofol and/or remifentanil should be used with caution in pediatric anesthesia.

关键词： nerve regeneration propofol remifentanil neural stem cells neural progenitor cells proliferation apoptosis differentiation [Ca^2+]i neural regeneration

Bonding Energies and Structural Study of Alkylaluminium

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Chinese Journal of Structural Chemistry 2010年第6期29卷 833-838页

作者： ZHAO Yan-Yun CHENG Xue-li li li-qing li Zhen Department of Chemistry and Environmental Sciences Taishan University

Neutral aluminium alkyls are well known to act as ethylene oligomerization and polymerization catalysts and *** the basis of the full optimization of alkylaluminium compounds with Gaussian 98 program package at the B3LYP/6-31G＊＊ level,the selected structures and bonding energies were investigated *** geometries and bonding energies of AlR3（R = H,CH3,C2H5,C3H7,C4H9） and Al（C2H5）2R＇（R＇ = C2H5,C3H7,C4H9,C5H11,C6H13） were investigated extensively,and we found that,along with the prolongation of carbon chains the terminal C-C bond is shortened gradually until to a constant value of about 0.1532 nm in C4H9;and the bonding energy almost remains *** dative bonding of C2H4 to Al（C2H5）3,whose bonding energy is only 15.30 kJ/mol,is very weak.

关键词： alkylaluminium bonding energy molecular geometry steric effect