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KLF4 facilitates chromatin accessibility remodeling in porcine early embryos

Science China(Life Sciences) 2024年第1期67卷 96-112页

作者： Wei Zhu Guowei Bu Ruifeng Hu Jixiang Zhang Lianyong Qiao Kai Zhou Tingting Wang Qiao Li Jingjing Zhang Linhui Wu Yali Xie Taotao Hu shichun Yang Jiaqi Guan Xiaoyu Chu juanjuan shi Xia Zhang Falong Lu Xin Liu Yi-Liang Miao Institute of Stem Cell and Regenerative Biology College of Animal Science and Veterinary MedicineHuazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction(Huazhong Agricultural University)Ministry of EducationWuhan 430070China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyInnovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China Frontiers Science Center for Animal Breeding and Sustainable Production Huazhong Agricultural UniversityWuhan 430070China Hubei Hongshan Laboratory Wuhan 430070China

Chromatin accessibility remodeling driven by pioneer factors is critical for the development of early *** studies have illustrated several pioneer factors as being important for agricultural animals,but what are the pioneer factors and how the pioneer factors remodel the chromatin accessibility in porcine early embryos is not *** employing low-input DNase-seq(liDNase-seq),we profiled the landscapes of chromatin accessibility in porcine early embryos and uncovered a unique chromatin accessibility reprogramming pattern during porcine preimplantation *** data revealed that KLF4 played critical roles in remodeling chromatin accessibility in porcine early *** down of KLF4 led to the reduction of chromatin accessibility in early embryos,whereas KLF4 overexpression promoted the chromatin openness in porcine ***,KLF4 deficiency resulted in mitochondrial dysfunction and developmental failure of porcine *** addition,we found that overexpression of KLF4 in blastocysts promoted lipid droplet accumulation,whereas knockdown of KLF4 disrupted this *** together,our study revealed the chromatin accessibility dynamics and identified KLF4 as a key regulator in chromatin accessibility and cellular metabolism during porcine preimplantation embryo development.

关键词： porcine embryos liDNase-seq chromatin accessibility KLF4 mitochondrion lipid droplets

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杂色曲霉β-葡萄糖苷酶分离纯化及酶学性质研究

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中国饲料 2024年第13期 48-54页

作者：付跃李书安石娟娟罗奉奉河池学院化学与生物工程学院广西河池546300 微生物及植物资源开发利用广西高校重点实验室广西河池546300 河池学院农业生物技术应用研究中心广西河池546300

试验旨在从杂色曲霉发酵液中分离纯化β-葡萄糖苷酶,并对其进行酶学性质研究。利用ENrich Q,10×100离子交换色谱法对杂色曲霉产β-葡萄糖苷酶分离纯化,采用SDS-PAGE测定其分子质量。结果表明:该β-葡萄糖苷酶的分子质量约为88.5 kDa,... 详细信息

试验旨在从杂色曲霉发酵液中分离纯化β-葡萄糖苷酶,并对其进行酶学性质研究。利用ENrich Q,10×100离子交换色谱法对杂色曲霉产β-葡萄糖苷酶分离纯化,采用SDS-PAGE测定其分子质量。结果表明:该β-葡萄糖苷酶的分子质量约为88.5 kDa,纯化倍数为53.44,回收率为70.78%,比酶活为1438.11 U/mg。该β-葡萄糖苷酶最适反应温度为50℃,最适反应pH为5.5;在温度20~50℃,pH 5.0~7.0时有较好的稳定性。Mn^(2+)对该酶具有明显的促进作用;Co^(2+)、Cu^(2+)、Cd^(2+)对该酶表现出抑制作用;而Na^(+)、Mg^(2+)、K^(+)、Ca^(2+)、Ba^(2+)对该酶无明显影响。该酶以水杨苷为底物时,米氏常数K_(m)为0.48 mg/mL,最大反应速率V_(m)为0.04 mg/(min·mL)。试验从杂色曲霉发酵液中成功分离出一种β-葡萄糖苷酶,为纤维素类饲料的应用提供了数据支撑。

关键词：杂色曲霉 β-葡萄糖苷酶分离纯化酶学性质

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频域特征驱动的车辆旋转部件灰色故障诊断

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振动．测试与诊断 2024年第3期44卷 514-522,619,620页

作者：苏舟石娟娟关云辉张晶黄伟国沈长青朱忠奎苏州大学轨道交通学院苏州215131 中车戚墅堰机车车辆工艺研究所有限公司常州213011

根据不同故障引起的振动信号频域特征各异的特点,首先,运用调Q小波变换(tunable Q-factor wavelet transform,简称TQWT)的频率响应对车辆旋转部件振动信号或其包络信号进行分析,构建以信号在不同频段各子带能量占比为元素的特征向量;其... 详细信息

根据不同故障引起的振动信号频域特征各异的特点,首先,运用调Q小波变换(tunable Q-factor wavelet transform,简称TQWT)的频率响应对车辆旋转部件振动信号或其包络信号进行分析,构建以信号在不同频段各子带能量占比为元素的特征向量;其次,针对灰色接近关联度在处理2组相交的序列时存在的两序列变化趋势不同、原始累差小而导致关联度过大的问题,提出了灰色绝对接近关联度模型;最后,在所构建的频域特征向量驱动下,计算其与标准模式的灰色绝对接近关联度,对车辆关键旋转部件故障状态进行识别。利用所提方法对列车轮对轴承和汽车变速器齿轮箱不同运行状态的振动信号进行分析,结果表明,所提方法能够准确识别车辆旋转部件的运行状态和故障类型,通过对比分析验证了该方法的优越性。

关键词：轴承齿轮箱故障诊断故障辨识能量分布

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黄芪多糖对绵羊精液冷冻保存的影响

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中国畜牧兽医 2024年第5期51卷 2007-2014页

作者：王振国李瀚森张丽周千时娟娟石磊任有蛇山西农业大学动物科学学院太谷030801

【目的】试验旨在研究稀释液中添加黄芪多糖对杜泊种公羊精液冷冻保存效果的影响。【方法】使用假阴道法采集6只成年杜泊种公羊的精液,将活率>80%的精液混合,使用Tris-果糖-海藻糖-柠檬酸基础稀释液和降温稀释液对绵羊新鲜精液进行逐步... 详细信息

【目的】试验旨在研究稀释液中添加黄芪多糖对杜泊种公羊精液冷冻保存效果的影响。【方法】使用假阴道法采集6只成年杜泊种公羊的精液,将活率>80%的精液混合,使用Tris-果糖-海藻糖-柠檬酸基础稀释液和降温稀释液对绵羊新鲜精液进行逐步稀释,低温缓慢降温到4℃后,分别于含黄芪多糖(0、0.01、0.05和0.1 mg/mL)的冷冻稀释液中进行平衡处理,将平衡后的精液分装于0.25 mL冻精细管中,置于液氮上方熏蒸后于液氮中冷冻保存。通过精子辅助分析系统检测冷冻-解冻后精子质量指标(活力和活率)和精子运动参数(平均路径速度、曲线运动速度、直线运动速度、摆动指数、线性度和直线运动指数),采用精子低渗肿胀试验检测质膜完整性,使用双荧光染色检测精子DNA完整性和线粒体活性。【结果】精液冷冻前后,绵羊精子活力、活率和运动能力均明显降低。0.01 mg/mL黄芪多糖添加组精液冷冻解冻后精子活力、活率、平均路径速度、线性度、摆动指数以及线粒体活性均显著高于其余各组(P0.05)。【结论】冷冻稀释液中添加0.01 mg/mL黄芪多糖能够保护绵羊精子结构,有效提高冷冻-解冻后绵羊精子活力、活率和运动能力,改善绵羊精液冷冻保存效果。

关键词：杜泊羊精液冷冻保存黄芪多糖

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长江行蓄洪空间数字孪生实景三维模型构建研究

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水利水电快报 2024年第1期45卷 89-94页

作者：王锴华甘拯石娟娟长江空间信息技术工程有限公司(武汉) 湖北武汉430010

数字孪生是流域数字化转型的重要技术手段,为有力支撑数字流域孪生中数据底板的构建,以长江中下游三洲联垸行蓄洪空间为研究对象,利用飞马无人机D200获取测区五视角影像,基于Context Capture软件全自动构建实景三维模型,并利用野外量测... 详细信息

数字孪生是流域数字化转型的重要技术手段,为有力支撑数字流域孪生中数据底板的构建,以长江中下游三洲联垸行蓄洪空间为研究对象,利用飞马无人机D200获取测区五视角影像,基于Context Capture软件全自动构建实景三维模型,并利用野外量测的检查点对模型精度进行评定。研究表明:基于倾斜摄影构建的实景三维模型平面误差和高程误差分别为0.104 m和0.121 m,均在3个像素以内,满足1∶500比例尺测图要求。基于高精度实景三维模型构建的三维数字场景,可为行蓄洪空间在实时调度模拟分析中的运用提供参考。

关键词：实景三维模型数字孪生倾斜摄影行蓄洪空间

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Continual learning fault diagnosis:A dual-branch adaptive aggregation residual network for fault diagnosis with machine increments

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Chinese Journal of Aeronautics 2023年第6期36卷 361-377页

作者： Bojian CHEN Changqing SHEN juanjuan shi Lin KONG Luyang TAN Dong WANG Zhongkui ZHU School of Rail Transportation Soochow UniversitySuzhou 215131China China Chang Guang Satellite Technology CO.LTD Changchun 130102China Department of Industrial Engineering and Management and in the State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200030China

As a data-driven approach, Deep Learning(DL)-based fault diagnosis methods need to collect the relatively comprehensive data on machine fault types to achieve satisfactory performance. A mechanical system may include multiple submachines in the real-world. During condition monitoring of a mechanical system, fault data are distributed in a continuous flow of constantly generated information and new faults will inevitably occur in unconsidered submachines, which are also called machine increments. Therefore, adequately collecting fault data in advance is difficult. Limited by the characteristics of DL, training existing models directly with new fault data of new submachines leads to catastrophic forgetting of old tasks, while the cost of collecting all known data to retrain the models is excessively high. DL-based fault diagnosis methods cannot learn continually and adaptively in dynamic environments. A new Continual Learning Fault Diagnosis method(CLFD) is proposed in this paper to solve a series of fault diagnosis tasks with machine increments. The stability–plasticity dilemma is an intrinsic issue in continual learning. The core of CLFD is the proposed Dual-branch Adaptive Aggregation Residual Network(DAARN).Two types of residual blocks are created in each block layer of DAARN: steady and dynamic blocks. The stability–plasticity dilemma is solved by assigning them with adaptive aggregation weights to balance stability and plasticity, and a bi-level optimization program is used to optimize adaptive aggregation weights and model parameters. In addition, a feature-level knowledge distillation loss function is proposed to further overcome catastrophic forgetting. CLFD is then applied to the fault diagnosis case with machine increments. Results demonstrate that CLFD outperforms other continual learning methods and has satisfactory robustness.

关键词： Catastrophic forgetting Continual learning Fault diagnosis Knowledge distillation Machine increments Stability-plasticity dilemma

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Synchronous chirp mode extraction: A promising tool for fault diagnosis of rolling element bearings under varying speed conditions

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Chinese Journal of Aeronautics 2022年第1期35卷 348-364页

作者： Xingxing JIANG Qiang HUANG Changqing SHEN Qian WANG Kun XU Jie LIU juanjuan shi Zhongkui ZHU School of Rail Transportation Soochow UniversitySuzhou 215131China Wenzheng College of Soochow University Suzhou 215104China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Sclool of Hydropower and Infonnation Engineering Huazhong University of Science and TechnologyWuhan 430074China

As critical components in modern aerospace productions,rolling element bearings(REBs)generally work under varying speed conditions,which brings great challenges to their operating health *** novel time–frequency decomposition(TFD)algorithms are established recently to extract nonlinear features from the non-stationary signals effectively,which are promising for realizing fault diagnosis of REBs under varying speed ***,numerous personal experiences must be incorporated and the anti-noise performance of these methods needs to be further *** these issues,a synchronous chirp mode extraction(SCME)-based REB fault diagnosis method is proposed for the health monitoring of REBs under varying speed conditions in this *** mainly consists of following two parts.(a)The shaft rotational frequency(SRF)is initially estimated from the low-frequency band of the vibration ***,an adaptive refining strategy is incorporated to obtain a suitable bandwidth parameter.(b)A cycle-one-step estimation frame is constructed to extract synchronous modes from the envelope waveform of the vibration ***,a synchronous mode spectrum(SMS)is generated using the information of the extracted synchronous modes,which is a novel REBs fault diagnosis technique with tacholess and *** contrast to the current TFD algorithms,the proposed method needs fewer input parameters and owns a well anti-noise performance because there is no iterative optimization in the procedure of construction of *** a result,the health conditions of REBs are evaluated by detecting the exhibited features in the *** and experiments are conducted to validate the effectiveness of the proposed method in terms of REB fault *** results demonstrate that the proposed method outperforms the current TFD algorithm and the conventional order tracking technique for fault diagnosis of REB under varying speed conditions.

关键词： Envelope analysis Fault diagnosis Order tracking Rolling element bearing Varying speed

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Carbon film encapsulated Fe_2O_3: An efficient catalyst for hydrogenation of nitroarenes

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Chinese Journal of Catalysis 2017年第11期38卷 1909-1917页

作者： Yingyu Wang juanjuan shi Zihao Zhang Jie Fu Xiuyang Lü Zhaoyin Hou Key Laboratory of Biomass Chemical Engineering of Ministry of Education Department of Chemistry Zhejiang University Hangzhou 310028 ZhejiangChina Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 Zhejiang China

Iron catalysis has attracted a wealth of interdependent research for its abundance,low price,and ***,a convenient and stable iron oxide(Fe2O3)‐based catalyst,in which active Fe2O3nanoparticles(NPs)were embedded into carbon films,was prepared via the pyrolysis of iron‐polyaniline complexes on carbon *** obtained catalyst shows a large surface area,uniform pore channel distribution,with the Fe2O3NPs homogeneously dispersed across the hybrid *** electron microscopy,Raman spectroscopy and X‐ray diffraction analyses of the catalyst prepared at900°C(Fe2O3@G‐C‐900)and an acid‐pretreated commercial activated carbon confirmed that additional carbon materials formed on the pristine carbon *** of high‐resolution transmission electron microscopy images also revealed that the Fe2O3NPs in the hybrid were encapsulated by a thin carbon *** Fe2O3@G‐C‐900composite was highly active and stable for the direct selective hydrogenation of nitroarenes to anilines under mild conditions,where previously noble metals were *** synthetic strategy and the structure of the iron oxide‐based composite may lead to the advancement of cost‐effective and sustainable industrial processes.

关键词： Carbon film Encapsulation Iron catalysis Pyrolysis Hydrogenation Nitroarene

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难治性子宫腺肉瘤1例

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国际医药卫生导报 2024年第3期30卷 503-507页

作者：时娟娟杜超李南韩珊珊崔秀娟济宁医学院附属滕州市中心人民医院妇科滕州277599

子宫腺肉瘤被认为低度恶性子宫肿瘤。子宫腺肉瘤发病率低,缺乏特异性临床表现及实验室和影像学检查,大部分子宫腺肉瘤患者预后较好。本文报道1例难治性子宫腺肉瘤患者术后迅速出现转移并致死亡的诊疗经过,以提高临床医师对该疾病的认识... 详细信息

子宫腺肉瘤被认为低度恶性子宫肿瘤。子宫腺肉瘤发病率低,缺乏特异性临床表现及实验室和影像学检查,大部分子宫腺肉瘤患者预后较好。本文报道1例难治性子宫腺肉瘤患者术后迅速出现转移并致死亡的诊疗经过,以提高临床医师对该疾病的认识并作出个性化处理。

关键词：子宫腺肉瘤转移预后死亡

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Selective hydrogenation of phenol to cyclohexanone in water over Pd catalysts supported on Amberlyst-45

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Chinese Journal of Catalysis 2016年第2期37卷 234-239页

作者：赵梦思石娟娟侯昭胤浙江大学化学系催化研究所浙江杭州310028

A series of Pd catalysts were prepared on different supports（Fe2O3,SiO2,ZnO,MgO,Al2O3,carbon,and Amberlyst-45） and used in the selective hydrogenation of phenol to cyclohexanone in *** Amberlyst-45 supported Pd catalyst（Pd/A-45） was highly active and selective under mild conditions（40-100 ℃,0.2-1 MPa）,giving a selectivity of cyclohexanone higher than 89%even at complete conversion of *** with different Pd loadings（or different particle sizes） confirmed that the formation of cyclohexanone was a structure sensitive reaction,and Pd particles of12-14 nm on Amberlyst-45 gave better selectivity and stability.

关键词： Phenol Hydrogenation Cyclohexanone Palladium Amberlyst-45 resin Supported catalyst

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