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The Mixed-Mode Fatigue Crack Propagation Model of Piezoelectric Materials Under Electric Fatigue Loading by the J_(k)-Integral

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Acta Mechanica Solida Sinica 2024年第4期37卷 634-641页

作者： Xianghua Chen Chunguang Wang qun li The Institute of Xi’an Aerospace Solid Propulsion Technology Xi’an710025China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China

The electric fatigue load has a significant effect on the crack propagation behavior and failure life of piezoelectric materials and devices. In this paper, an electrical mixed-mode fatigue crack propagation model for piezoelectric materials is proposed based on the piezoelectric J_(k)-integral theory. The crack initiation, propagation, and life prediction criteria of piezoelectric materials under electric fatigue loading are given by this model, and the finite element simulation model is established to study the electrical mixed-mode crack propagation behavior of piezoelectric structures. Meanwhile, the electrical mixed-mode fatigue crack propagation model is applied to the fatigue crack propagation behavior of a piezoelectric typical defective structure, the crack–hole interference model. The mixed-mode crack propagation, fatigue life, and the interference behavior between the crack and hole at various hole locations of the crack–hole interference model are well recognized by this model. The crack propagation behavior under different electrical load intensities is also considered. The results show that the hole in front of the crack tip inhibits crack propagation to a certain extent, and the strength of electrical load affects the fatigue life of piezoelectric materials and structures. Therefore, the proposed electrical mixed-mode fatigue crack propagation model provides a reference for predicting the mixed-mode fatigue crack propagation behavior and fatigue life of piezoelectric structures under electric fatigue loading.

关键词： Configurational force J_(k)-integral Piezoelectric Mixed-mode crack propagation life prediction

Meta label associated loss for fine-grained visual recognition

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Science China(Information Sciences) 2024年第6期67卷 230-247页

作者： Yanchao li Fu XIAO Hao li qun li Shui YU School of Computer Science Nanjing University of Posts and Telecommunications School of Network Engineering Zhoukou Normal University School of Computer Science University of Technology Sydney

Recently, intensive attempts have been made to design robust models for fine-grained visual recognition, most notably are the impressive gains for training with noisy labels by incorporating a reweighting strategy into a meta-learning framework. However, it is limited to up or downweighting the contribution of an instance for label reweighting approaches in the learning process. To solve this issue, a novel noise-tolerant method with auxiliary web data is proposed. Specifically, first, the associations made from embeddings of well-labeled data with those of web data and back at the same class are measured. Next, its association probability is employed as a weighting fusion strategy into angular margin-based loss, which makes the trained model robust to noisy datasets. To reduce the influence of the gap between the well-labeled and noisy web data, a bridge schema is proposed via the corresponding loss that encourages the learned embeddings to be coherent. Lastly, the formulation is encapsulated into the meta-learning framework, which can reduce the overfitting of models and learn the network parameters to be noise-tolerant. Extensive experiments are performed on benchmark datasets, and the results clearly show the superiority of the proposed method over existing state-of-the-art approaches.

关键词： label associated loss weighting noisy samples fine-grained visual recognition noise-tolerant learning meta-learning

凡纳对虾parkin共调基因和parkin在抗白斑综合征病毒中的表达分析和SNP开发

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渔业科学进展 2025年第1期46卷 194-209页

作者：薛倩李旭鹏李洋栾生罗坤孔杰邢群孟宪红浙江海洋大学水产学院浙江舟山316021 海水养殖生物育种与可持续产出全国重点实验室中国水产科学研究院黄海水产研究所山东青岛266071 青岛海洋科技中心海洋渔业科学与食物产出过程功能实验室山东青岛266237 邦普种业科技有限公司山东潍坊261311

本实验室前期研究中基于全基因组关联分析(GWAS)方法筛选到抗白斑综合征病毒(WSSV)候选基因:parkin共调基因(PACRG)。PACRG与帕金森病相关基因parkin共用一个双向启动子,二者共同参与细胞自噬过程,从而在细胞保护方面发挥作用。本研究... 详细信息

本实验室前期研究中基于全基因组关联分析(GWAS)方法筛选到抗白斑综合征病毒(WSSV)候选基因:parkin共调基因(PACRG)。PACRG与帕金森病相关基因parkin共用一个双向启动子,二者共同参与细胞自噬过程,从而在细胞保护方面发挥作用。本研究对凡纳对虾(Penaeus vannamei)PACRG和parkin在抗WSSV中的功能进行探讨,对其mRNA和氨基酸序列进行特征分析,利用real-timePCR技术检测对虾感染WSSV后不同时间、不同组织中PACRG和parkin的表达水平。通过荧光原位杂交技术(FISH)进行空间定位。利用PCR和Sanger测序技术获得单核苷酸多态性位点(SNP)并进行抗WSSV的关联分析。结果显示,PACRG开放阅读框(ORF)全长600bp,编码199个氨基酸,预测包含一个ParcG结构域。parkinORF序列全长1653bp,编码550个氨基酸,预测包含UBQ、IBR结构域和一个信号肽结构。与多物种进行同源序列比对发现,凡纳对虾PACRG氨基酸序列与日本对虾(Penaeus japonicus)的同源性高达89.70%;凡纳对虾parkin氨基酸序列与中国对虾(Penaeus chinensis)和斑节对虾(Penaeus monodon)的同源性高达93.45%。PACRG和parkin蛋白的保守性较高。感染WSSV后,PACRG和parkin在对虾肝胰腺、鳃、肌肉和眼柄中的表达水平发生显著变化,其中,眼柄中PACRG和parkin表现出极相似的组织表达模式。在肌肉中,PACRGmRNA和WSSV在空间位置上呈现高度重叠状态。结合上述结果,推测PACRG和parkin在凡纳对虾与WSSV的互作中发挥功能。在PACRG中筛选到2个SNP位点,在parkin中筛选到15个SNP位点,其中位于parkin非翻译区(UTR)的5个SNP位点与抗WSSV性状显著相关。本文为研究凡纳对虾抗WSSV的分子机制和抗病分子育种提供了理论依据和参考数据。

关键词：凡纳对虾白斑综合征病毒(WSSV) parkin共调基因(PACRG) parkin基因 SNP

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Subharmonic and Combination Resonance of Rotating Pre-deformed Blades Subjected to High Gas Pressure

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Acta Mechanica Solida Sinica 2020年第5期33卷 635-649页

作者： Bo Zhang Hu Ding li-qun Chen School of Science Chang’an UniversityXi’an710064ShaanxiChina Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200444China School of Science Harbin Institute of TechnologyShenzhen518055China

The present paper deals with the investigation of dynamic responses of a rotating pre-deformed blade in four cases of resonance,including two subharmonic resonances and two combination *** dimensionless gas excitation amplitude is assumed to share the same order with the dimensionless vibration *** cases of resonance are confirmed by examining the secular *** theoretical analysis framework is established for each resonance case based on the method of multiple *** original dynamic system is integrated numerically by the Runge–Kutta *** frequency components and phases obtained from fast Fourier transform of the numerical response are used to verify the theoretical *** the purpose of contrast,modulation equations are also integrated *** all four resonance cases,the theoretical results agree well with the numerical *** studies are conducted to clarify the effects of system parameters on the perturbation *** results are obtained for the rotating blade.A quasi-saturation phenomenon occurs in both combination resonances of summed type and difference type,and the corresponding limit value of the second-mode response can be reduced by decreasing the external detuning *** quasi-saturation phenomenon of rotating blade only appears with high gas *** subharmonic resonance of second mode and the combination resonance of summed type are hard to excite in practice compared with the other two cases.

关键词： Internal resonance Subharmonic resonance Combination resonance Rotating blade Stability

Approach and landing trajectory optimization for Reusable Launch Vehicle using Adaptive Gauss pseudo-spectral method 36

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Approach and landing trajectory optimization for Reusable La...

Comparison of summer Arctic sea ice surface temperatures from in situ and MODIS measurements

第36届中国控制会议

作者： Chaofan Zhang qun Zong qi Dong Bailing Tian Zhiyu li Jing Zong School of Electrical and Information Engineering Tianjin University College of Precision Instrument and Opto-Electronics Engineering Tianjin University

ISBN: (纸本)9781538629185

The Approach and Landing（A＆L） trajectory optimization is important for reusable launch vehicle（RLV） to deliver it to its landing site safely and reliably. And the trajectory should satisfy multi-constraints and path features. In this paper, the 3D dynamics of RLV in the A＆L phase is *** the the adaptive Gauss pseudo-spectral method（AGPM） is used to solve the A＆L trajectory optimization problem. The adaptive method in GPM can improve the accuracy of the trajectory and accelerate convergence velocity of algorithm effectively. The simulation results of the typical RLV（X-33） demonstrate the feasibility of the trajectory optimization scheme which can let the RLV land securely.

关键词： Approach and Landing(A&L) reusable launch vehicle(RLV) adaptive Gauss pseudo-spectral(AGPM) trajectory optimization

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Acta Oceanologica Sinica 2020年第9期39卷 18-24页

作者： Na li Bingrui li Ruibo Lei qun li Polar Research Institute of China Shanghai 200136China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

Ship-borne infrared radiometric measurements conducted during the Chinese National Arctic Research Expedition(CHINARE)in 2008,2010,2012,2014,2016 and 2017 were used for in situ validation studies of the Moderate Resolution Imaging Spectroradiometer(MODIS)sea ice surface temperature(IST)*** of sea ice were made using a KT19.85 radiometer mounted on the Chinese icebreaker Xuelong between July and September over six *** MODIS-derived ISTs from the satellites,Terra and Aqua,both show close correspondence with ISTs derived from radiometer spot measurements averaged over areas of 4 km×4 km,spanning the temperature range of 262–280 K with a±1.7 K(Aqua)and±1.6 K(Terra)*** consistency of the results over each year indicates that MODIS provides a suitable platform for remotely deriving surface temperature data when the sky is *** into factors that cause the MODIS IST bias(defined as the difference between MODIS and KT19.85 ISTs)shows that large positive bias is caused by increased coverage of leads and melt ponds,while large negative bias mostly arises from undetected *** vapor fog forming over Arctic sea ice may explain the cold bias when cloud cover is below 20%.

关键词： sea ice surface temperature thermal radiometer MODIS Arctic Ocean

Small interfering RNA targeting HMGN5 induces apoptosis via modulation of a mitochondrial pathway and Bcl-2 family proteins in prostate cancer cells

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Asian Journal of Andrology 2012年第3期14卷 487-492,I0009页

作者： Xiao-Yu Zhang Zhong-qiang Guo Shi-qi Ji Min Zhang Ning Jiang Xue-Song li li-qun Zhou Department of Urology Peking University First Hospital and the Institute of UrologyPeking UniversityBeijing 100034China

We investigated the importance of HMGN5, a nuclear protein that binds to nucleosomes, unfolds chromatin, and affects transcription, in the LNCaP prostate cancer cell line. We also examined the molecular mechanisms that promote apoptosis of LNCaP cells after infection with small interfering RNA （siRNA） targeting HMGN5 （siRNA-HMGN5）. The androgen-dependent LNCaP human prostate cancer cells were infected with siRNA-HMGN5. Apoptosis was detected using the Annexin V-PE/7-AAD double staining and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling （TUNEL） assays. Mitochondrial membrane potential was measured by JC-1 staining. HMGN5and GAPDHmRNA expression were determined using real-time PCR. Bcl-2 and other apoptosis-related protein levels were determined by Western blot analysis. Caspase activity was measured by cleavage of the caspase substrate. Infection with siRNA targeting HMGN5 efficiently and specifically reduced the HMGN5 expression in LNCaP cells. The downregulation of HMGN5 induced remarkable apoptosis of LNCaP cells and resulted in the reduction of mitochondrial membrane potential. The induction of cell apoptosis was accompanied by the upregulation of Bax, the Bax/Bcl-2 ratio and the activation of caspase3. The HMGN5-targeted siRNA was effective in downregulating the expression of HMGN5 in androgen-dependent prostate cancer cells and inducing cell apoptosis via the regulation of a caspase-related mitochondrial pathway and Bcl-2 family proteins. This study suggests that HMGN5 may be a potential molecular target with therapeutic relevance for the treatment of prostate cancer.

关键词： apoptosis HMGN5 mitochondrial pathway prostate cancer siRNA

Interleukin-4 affects microglial autophagic flux

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Neural Regeneration Research 2019年第9期14卷 1594-1602页

作者： Run-Hong Tang Rui-qun qi Hua-Yan liu Department of Neurology the First Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Dermatology Key Laboratory of Immunodermatologythe First Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Interleukin-4 plays an important protective role in Alzheimer’s disease by regulating microglial phenotype,phagocytosis of amyloid-β,and secretion of anti-inflammatory and neurotrophic ***,increasing evidence has suggested that autophagy regulates innate immunity by affecting M1/M2 polarization of microglia/***,the role of interleukin-4 in microglial autophagy is *** view of this,BV2 microglia were treated with 0,10,20 or 50 ng/mL interleukin-4 for 24,48,or 72 ***,light chain 3-II and p62 protein expression levels were detected by western blot ***2 microglia were incubated with interleukin-4(20 ng/mL,experimental group),3-methyladenine(500μM,autophagy inhibitor,negative control group),rapamycin(100 nM,autophagy inductor,positive control group),3-methyladenine+interleukin-4(rescue group),or without treatment for 24 hours,and then exposed to amyloid-β(1μM,model group)or vehicle control(control)for 24 ***3-II and p62 protein expression levels were again detected by western blot *** addition,expression levels of multiple markers of M1 and M2 phenotype were assessed by real-time fluorescence quantitative polymerase chain reaction,while intracellular and supernatant amyloid-βprotein levels were measured by enzyme-linked immunosorbent *** results showed that interleukin-4 induced microglial autophagic flux,most significantly at 20 ng/mL for 48 ***-4 pretreated microglia inhibited blockade of amyloid-β-induced autophagic flux,and promoted amyloid-βuptake and degradation partly through autophagic flux,but inhibited switching of amyloid-β-induced M1 phenotype independent on autophagic *** results indicate that interleukin-4 pretreated microglia increases uptake and degradation of amyloid-βin a process partly mediated by autophagy,which may play a protective role against Alzheimer’s disease.

关键词： nerve regeneration Alzheimer’s disease interleukin-4 amyloid-β microglial autophagy microglial polarization microglia M1 phenotype M2 phenotype peptide degradation neural regeneration

Prognostic factors influencing outcome in adult liver transplantation using hypernatremic organ donation after brain death

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 371-377页

作者： Zheng-Jun Zhou Guang-Shun Chen Zhong-Zhou Si qiang li Yang-Yang Bin Hai-Zhi qi Jie-qun li Center of Organ Transplantation The Second Xiangya Hospital of Central South UniversityChangsha 410011China

Background:Hypernatremic donors was regarded as the expanded criteria donors in liver *** study was to investigate the effects of donor hypernatremia on the outcomes of liver transplantation and identify the prognostic factors possibly contributing to the poor ***:Donor serum sodium levels before procurement were categorized as normal sodium(liver grafts from hypernatremia to reperfusion wasliver ***:There were no significant differences in the 1-year survival rates of grafts and recipients,1-year graft loss rates and early events among the normal,moderate high and severe high sodium ***,the overall survival rates of grafts and recipients in subgroup A were significantly higher than those in subgroup *** model showed that the exposure time(HR=1.117;95%CI:1.053–1.186;Pliver *** hypernatremia liver donors,minimization of the exposure time from hypernatremia to reperfusion is critical to prevent graft loss.

关键词： liver transplantation Hypernatremia Expanded criteria donors