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Changes in the biochemical composition and enzyme activity during dormancy release of Cyclocarya paliurus seeds

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Forestry Studies in China 2007年第1期9卷 7-13页

作者： fang sheng-zuo Wang Jia-yuan College of Forest Resources and Environment Nanjing Forestry University Nanjing 210037 P. R. China

Cyclocarya paliurus is only propagated from seeds which have pronounced dormancy. Overcoming seed dormancy is an important component of efficient and cost-effective seedling production of Cyclocarya paliurus. Changes in biochemical composition and enzyme activity were investigated during dormancy release. The activities of all the studied enzymes in the stratified seeds increased significantly, compared to those in the control samples. Of the enzymes examined, the activities of protease increased the most （413.8%）, followed by peroxidase （278.7%）, lipase （161.0%）, glucose-6-phosphate dehydrognase （149.1%） and amylase （60.6%） after 8 months of stratification. Crude fat and protein constituted the bulk of the storage reserves in mature seeds of C. pal# urus. Compared with the seeds before stratification, about 45% of the starch, 46% of the protein and 11% of the crude fat were depleted during dormancy release of C. paliurus seeds, while the soluble sugar content was enhanced by 101.5% in the germinating seeds. Correlation analysis showed, during dormancy release of C. paliurus seeds, a close positive relationship between POD and G6PDH activity as well as soluble sugar content and amylase activity, while there was a significant negative relationship between storage substances and their related enzyme activities.

关键词： Cyclocaryapaliurus enzyme activity seed dormancy soluble sugar storage substances stratification

敲低IL-33下调炎症因子和NLRP3表达抑制哮喘小鼠炎症反应

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细胞与分子免疫学杂志 2024年第7期40卷 577-584页

作者：林玛丽李晓飞曹丽梅陈熙泼徐丽丹盛放浙江大学医学院附属金华医院妇女儿童院区(金华市妇幼保健院金华市妇女儿童医院)儿一科浙江金华321000 浙江大学医学院附属金华医院骨一科浙江金华321000

目的探讨白细胞介素33(IL-33)对哮喘小鼠炎症反应的调控机制。方法利用10μg/mL脂多糖(LPS)构建小鼠骨髓间充质干细胞(BMMSC)的体外细胞炎症模型,根据是否转染IL-33的小干扰RNA(si-IL-33)质粒和过表达(IL-33-OE)质粒,将细胞分成si-IL-33... 详细信息

目的探讨白细胞介素33(IL-33)对哮喘小鼠炎症反应的调控机制。方法利用10μg/mL脂多糖(LPS)构建小鼠骨髓间充质干细胞(BMMSC)的体外细胞炎症模型,根据是否转染IL-33的小干扰RNA(si-IL-33)质粒和过表达(IL-33-OE)质粒,将细胞分成si-IL-33组,IL-33-OE组和模型组。实时荧光定量PCR检测IL-33、含pyrin结构域核苷酸结合寡聚结构域样受体家族蛋白3(NLRP3)、IL-1β和IL-6的信使RNA(mRNA)表达水平。钙离子荧光探针检测试剂盒(Fluo-3 AM)检测钙离子含量,JC-1线粒体膜电位检测试剂盒检测线粒体膜电位变化。利用腹腔注射致敏剂和激发剂的方法建立小鼠哮喘模型,根据处理方案的不同,将哮喘小鼠分成si-IL-33组、IL-33-OE组和模型组,每组5只。ELISA试剂盒检测小鼠血清IL-1β、IL-6和NLRP3含量,HE染色和Masson染色检测肺组织的病变情况。结果与模型组相比,si-IL-33组的IL-33、NLRP3、IL-1β和IL-6的mRNA表达量均降低,IL-33-OE组的IL-33、NLRP3、IL-1β和IL-6的mRNA表达量增加。BMMSC中钙离子荧光降低,而IL-33-OE组中钙离子荧光升高。si-IL-33组细胞线粒体中JC-1以聚合物形式存在,呈明亮的红色荧光,细胞中的绿色荧光非常弱;说明si-IL-33组细胞线粒体稳定,线粒体功能尚在。使用IL-33-OE质粒处理使线粒体膜电位下降后,JC-1不能以聚合物形式存在于线粒体基质中,此时线粒体内红色荧光强度显著降低,而细胞质中的绿色荧光显著增强。si-IL-33组小鼠血清中IL-1β、IL-6、NLRP3的含量明显降低,而IL-33-OE组小鼠血清中IL-1β、IL-6、NLRP3的含量明显升高。si-IL-33组几乎未见炎细胞浸润,炎症缓解,上皮细胞正常。si-IL-33组肺组织的纤维增生部分趋于正常。与模型组相比,si-IL-33组的支气管壁总面积(WAt)/支气管基底膜周径(Pbm)和气管壁平滑肌面积(WAm)/Pbm降低,IL-33-OE组的WAt/Pbm和WAm/Pbm增加。结论敲低IL-33通过下调NLRP3、IL-1β、IL-6表达抑制哮喘小鼠的炎症反应。

关键词：哮喘白细胞介素33(IL-33) 含pyrin结构域核苷酸结合寡聚结构域样受体家族蛋白3(NLRP3) IL-1β IL-6

A Unified Thermodynamic Model of Flow-induced Crystallization of Polymer

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Chinese Journal of Polymer Science 2021年第11期39卷 1489-1495页

作者： Cui Nie Fan Peng Ting-Yu Xu Jun-fang sheng Wei Chen Liang-Bin Li National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Science and Technology of ChinaHefei 230026China

We propose a unified thermodynamic model of flow-induced crystallization of polymer(uFIC),which incorporates not only the conformational entropy reduction but also the contributions of flow-induced chain orientation,the interaction of ordered segments,and the free energy of crystal nucleus and crystal ***,it clarifies the determining parameters of the critical crystal nucleus size,and is able to account for the acceleration of nucleation,the emergence of precursor,different crystal morphologies and structures induced by *** on the nucleation barrier under flow,we analyze at which condition precursor may occur and how flow affects the competition among different crystal forms such as orthorhombic and hexagonal phases of *** to the uFIC model,the different crystal morphologies and structures in the flow-temperature space have been clarified,which give a good agreement with experiments of FIC.

关键词： Flow-induced crystallization Unified thermodynamic model Flow-induced chain orientation

Identification of two Monilia species from apricot in China

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Journal of Integrative Agriculture 2017年第11期16卷 2496-2503页

作者： YIN Liang-fen CAI Ming-li DU sheng-fang LUO Chao-xi Experimental Teaching Center of Crop Science College of Plant Science & Technology Huazhong Agricultural University Wuhan 430070 P.R.China Key Laboratory of Crop Disease Monitoring & Safety Control of Hubei Province~College of Plant Science & Technology Huazhong Agricultural University Wuhan 430070 P.R. China

Monilinia fructicola, Monilia mumecola and Monilia yunnanensis have been reported as the causal agents of brown rot disease on stone fruits in China. Up to date, these species have been identified from peach and plum, and M. mumecola has also been reported on apricot recently. To investigate whether M. fructicola and M. yunnanensis can cause brown rot disease on apricot in China, 37 isolates were collected from four orchards in Chongqing and Beijing municipalities in 2014. These isolates were divided into two phenotypes according to their distinct colony appearances. Two representative isolates of each phenotype and reference species of M. mumecola from apricot were selected for further analysis. Based on the morphological characterization and molecular identification, the two phenotypes of isolates were identified as M. fructicola and M. yunnanensis, respectively.

关键词： brown rot apricot Monilinia fructicola Monilia yunnanensis

全容积IVIM直方图分析对乳腺良恶性病变的影响

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中国CT和MRI杂志 2024年第3期22卷 82-85页

作者：李俊蔡小丽吴奇川牟方胜重庆大学附属三峡医院放射科重庆404000

目的探讨全容积测量体素内不相干运动(IVIM)直方图参数对乳腺良恶性病变的诊断价值。方法收集我院2021年2月-2022年10月术前行多模态磁共振检查并获得病理的153例女性共158例肿瘤。利用直方图处理软件得到肿瘤IVIM(D、D*、f)的直方图... 详细信息

目的探讨全容积测量体素内不相干运动(IVIM)直方图参数对乳腺良恶性病变的诊断价值。方法收集我院2021年2月-2022年10月术前行多模态磁共振检查并获得病理的153例女性共158例肿瘤。利用直方图处理软件得到肿瘤IVIM(D、D*、f)的直方图参数。采用两独立样本t检验(正态分布)或Mann-WhitneyU检验(偏态分布)比较乳腺良、恶性病灶的IVIM直方图参数的差异。绘制ROC评价IVIM直方图参数独立和联合鉴别诊断乳腺良、恶性病变的效能,Z检验评价联合诊断ROC下面积(AUC)差异性。单变量及多变量二元logisti回归分析独立影响因素。结果乳腺恶性病变116个,良性病变42个。良、恶性病变D(90th、熵、峰度、均值、中位数、最小值、偏度)、f峰度、D*(90th、熵、峰度、均值、中位数、最大值、偏度)单因素分析有统计学意义。AUC最大为D偏度(0.818);敏感度最高为D熵(0.957);特异度最高为D偏度(0.857);准确度最高为D偏度(0.797)。D直方图联合诊断AUC、敏感度、特异度、准确度分别为0.903、0.948、0.786、0.88;f直方图联合诊断分别为0.604、0.672、0.548、0.73;D*直方图联合诊断为0.833、0.897、0.619、0.823;IVIM直方图联合诊断为0.953、0.982、0.833、0.924;IVIM直方图联合诊断AUC面积最大,与D值、f值、D*直方图分别联合诊断AUC差异有统计学意义。D熵(OR=2.943;P=0.037)及D中位数(OR=0.984;P=0.029)为乳腺恶性病变独立影响因素。结论乳腺磁共振IVIM直方图参数联合能显著提高判断乳腺良恶性病变诊断效能,D熵及D中位数为乳腺恶性病变独立影响因素。

关键词：乳腺病变体素内不相干运动成像联合诊断影响因素

维普期刊数据库博看期刊

Nonlinear metamaterial enabled aeroelastic vibration reduction of a supersonic cantilever wing plate

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Applied Mathematics and Mechanics(English Edition) 2024年第10期45卷 1749-1772页

作者： Peng sheng Xin fang Dianlong YU Jihong WEN Laboratory of Science and Technology on Integrated Logistics Support College of Intelligence Science and TechnologyNational University of Defense TechnologyChangsha 410073China

The violent vibration of supersonic wings threatens aircraft *** paper proposes the strongly nonlinear acoustic metamaterial(NAM)method to mitigate aeroelastic vibration in supersonic wing *** employ the cantilever plate to simulate the practical behavior of a *** aeroelastic vibration model of the NAM cantilever plate is established based on the mode superposition method and a modified third-order piston *** aerodynamic properties are systematically studied using both the timedomain integration and frequency-domain harmonic balance *** presenting the flutter and post-flutter behaviors of the NAM wing,we emphasize more on the preflutter broadband vibration that is prevalent in *** results show that the NAM method can reduce the low-frequency and broadband pre-flutter steady vibration by 50%-90%,while the post-flutter vibration is reduced by over 95%,and the critical flutter velocity is also slightly *** clarified,the significant reduction arises from the bandgap,chaotic band,and nonlinear resonances of the NAM *** reduction effect is robust across a broad range of parameters,with optimal performance achieved with only 10%attached *** work offers a novel approach for reducing aeroelastic vibration in aircraft,and it expands the study of nonlinear acoustic/elastic metamaterials.

关键词： nonlinear acoustic metamaterial(NAM) hypersonic aeroelastic vibration vibration reduction fluid-structure interaction

A comparison of core–shell Si/C and embedded structure Si/C composites as negative materials for lithium-ion batteries

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Rare Metals 2021年第9期40卷 2440-2446页

作者： Shuai-Jin Wu Zhao-Hui Wu sheng fang Xiao-Peng Qi Bing Yu Juan-Yu Yang Grinm Group Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China China Automotive Battery Research Institute Co. Ltd.Beijing 101407China

Silicon materials have attracted wide attention as negative materials due to exceptional gravimetric capacity and abundance. The strategy of using nano-silicon materials as structural units to construct nano/micro-structured silicon-based negative materials for lithium-ion batteries has come into sight in recent years. In order to provide guidance for the material structure design of micro-sized silicon-based negative materials in practical application, in this work, two commercialized nano/micro-structured silicon-based negative materials with a specific capacity of about 650 mAh·g^(-1) were investigated and compared in the aspects of material microstructure, electrochemical performance of half cells, and electrode morphological evolution during cycling. The cycling performance(with capacity retention ratio of about 17% higher after 100 cycles) and electrode structure maintenance of the embedded structure Si/C material are superior to those of core–shell Si/C material. This research can provide guidance on design and application of nano/micro-structured silicon-based negative materials.

关键词： Lithium-ion battery Negative materials Silicon-based materials Material structure

Heterostructured Pd/PdO nanowires for selective and efficient CO_(2) electroreduction to CO

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Journal of Energy Chemistry 2022年第7期31卷 407-413,I0011页

作者： Tian-Jiao Wang Wen-sheng fang Yi-Ming Liu Fu-Min Li Pei Chen Yu Chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education)Shaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710062ShaanxiChina School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074HubeiChina

Palladium(Pd) nanostructures are highly promising electrocatalysts for the carbon dioxide electrochemical reduction(CO_(2) ER). At present, it is still challenge for the synthesis of Pd nanostructures with high activity, selectivity and stability. In this work, a facile PdII-complex pyrolysis method is applied to synthesize the high-quality one-dimensional heterostructured Pd/Pd O nanowires(Pd/Pd O H-NWs).The as-prepared Pd/Pd O H-NWs have a large electrochemically active surface area, abundant defects and Pd/Pd O heterostructure. Electrochemical measurement results reveal that Pd/Pd O H-NWs exhibit up to 94% CO Faraday efficiency with a current density of 11.6 m A cm^(-2) at an applied potential of -0.8 V. Meanwhile, Pd/Pd O H-NWs can achieve a stable catalytic process of 12 h for CO_(2) ER. Such outstanding CO_(2) ER performance of Pd/Pd O H-NWs has also been verified in the flow cell test. The density functional theory calculations indicate that Pd/Pd O heterostructure can significantly weaken the CO adsorption on Pd sites, which improves the CO tolerance and consequently enhances the catalytic performance of Pd/Pd O H-NWs for CO_(2) ER. This work highlights a facile complex pyrolysis strategy for the synthesis of Pd-based CO_(2) ER catalysts and provides a new application instance of metal/metal oxide heterostructure in electrocatalysis.

关键词： Pd/PdO nanowires Heterostructure Carbon dioxide electrochemical reduction Carbon monoxide Faraday efficiency

Machine Learning for Cataract Classification/Grading on Ophthalmic Imaging Modalities:A Survey

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Machine Intelligence Research 2022年第3期19卷 184-208页

作者： Xiao-Qing Zhang Yan Hu Zun-Jie Xiao Jian-sheng fang Risa Higashita Jiang Liu Research Institute of Trustworthy Autonomous Systems Southern University of Science and TechnologyShenzhen 518055China Department of Computer Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Tomey Corporation Nagoya 4510051Japan Cixi Institute of Biomedical Engineering Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315300China Guangdong Provincial Key Laboratory of Brain-inspired Intelligent Computation Southern University of Science and TechnologyShenzhen 518055China

Cataracts are the leading cause of visual impairment and blindness *** the years,researchers have achieved significant progress in developing state-of-the-art machine learning techniques for automatic cataract classification and grading,aiming to prevent cataracts early and improve clinicians′diagnosis *** survey provides a comprehensive survey of recent advances in machine learning techniques for cataract classification/grading based on ophthalmic *** summarize existing literature from two research directions:conventional machine learning methods and deep learning *** survey also provides insights into existing works of both merits and *** addition,we discuss several challenges of automatic cataract classification/grading based on machine learning techniques and present possible solutions to these challenges for future research.

关键词： Cataract classification and grading ophthalmic image machine learning deep learning