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壳聚糖-蒙脱土插层复合物对热应激雄性小鼠生殖功能的影响

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饲料研究 2024年第10期47卷 87-92页

作者：杨焕琳高元郭展辉谭飞陈浩然巨向红雍艳红广东海洋大学动物医学系广东湛江524088 广东海洋大学深圳研究院广东深圳518108

试验研究了壳聚糖-蒙脱土插层复合物(CS-MMT)对热应激雄性小鼠临床症状、睾丸形态和精子质量的保护作用。选择30只6周龄健康雄性ICR小鼠,随机分为对照组(CON组)、热应激组(HS组)、低剂量CS-MMT组(L组,50 mg/kg CS-MMT)、中剂量CS-MMT组(... 详细信息

试验研究了壳聚糖-蒙脱土插层复合物(CS-MMT)对热应激雄性小鼠临床症状、睾丸形态和精子质量的保护作用。选择30只6周龄健康雄性ICR小鼠,随机分为对照组(CON组)、热应激组(HS组)、低剂量CS-MMT组(L组,50 mg/kg CS-MMT)、中剂量CS-MMT组(M组,100 mg/kg CS-MMT)和高剂量CS-MMT组(H组,200 mg/kg CS-MMT),先连续给药7 d后,再热应激处理7 d,采集小鼠组织及精液进行观察。结果显示,与CON组相比,HS组小鼠睾丸组织损伤明显,精子密度显著降低(P<0.05),精子活率和顶体完整性极显著降低(P<0.01),精子畸形率和顶体畸形率极显著升高(P<0.01)。与HS组小鼠相比,CS-MMT组小鼠睾丸组织形态结构明显改善,精子密度增加,精子活率和顶体完整性极显著提高(P<0.01),精子畸形率和顶体畸形率极显著降低(P<0.01),呈剂量依赖性。研究表明,CS-MMT具有缓解热应激引起的雄性小鼠生殖功能损伤的作用,以200 mg/kg的给药量效果较好。

关键词：壳聚糖-蒙脱土插层复合物热应激精子质量生殖功能

Cationic liposome-mediated transfection of CD40 ligand gene inhibits hepatic tumor growth of hepatocellular carcinoma in mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 7-13页

作者： yong-fang JIANG Jing MA yan HE yong-hong ZHANG Yun XU Guo-zhong GONG Center for Liver Diseases the Second Xiangya Hospital Central South University Changsha 410011 China

Objective: To evaluate the efficacy of cationic liposome-mediated CD40 ligand (CD40L) gene therapy for hepato- cellular carcinoma. Methods: 1×106 of parental H22 cells or H22 cells transfected with the expression vector containing murine CD40L cDNA encoding the entire coding region (pcDNA3.1+-mCD40L) were inoculated subcutaneously into the left flanks of syngenic BALB/C mice. The tumor-bearing mice (tumor nodules 10 mm in maximal diameter) received the treatment of the intratumoral injection of pcDNA3.1+-mCD40L/Transfectam, pcDNA3.1+, or phosphate-buffered saline (PBS), or no treatment. The mice were monitored for tumor growth weekly. We examined mCD40L messenger ribonucleic acid (mRNA) expression by reverse transcription polymerase chain reaction (RT-PCR) and the histologic changes in tumors at two weeks after intratumoral injection using immunohistochemical staining of tumor tissues. Results: All mice inoculated with parental H22 cells developed a tumor subcutaneously, and the tumor size increased progressively within three weeks. However, the mice receiving H22-CD40L cells exhibited complete regression of the tumor two weeks after tumor cell inoculation. The tumor-bearing animals with the treatment of pcDNA3.1+ or PBS, or without treatment had progressive tumor growth, while those mice treated with pcDNA3.1+-mCD40L exhibited a significant inhibition of tumor growth. RT-PCR analysis showed that 783-bp fragments cor- responding to the mCD40L mRNA were amplified only from pcDNA3.1+-mCD40L treated tumors. The tumor samples from pcDNA3.1+-mCD40L-treated mice showed significant lymphocyte infiltration, apoptotic bodies, and confluent necrosis in the tumor tissues. Conclusion: The tumorigenicity of CD40L-expressing cells was abrogated when the cells were implanted subcu- taneously. In vivo gene therapy of established liver tumor nodules in mice by the intratumoral injection of pcDNA3.1+-mCD40L led to significant tumor inhibition. There was mCD40L mRNA expression in the

关键词： CD40 ligand gene Hepatocellular carcinoma (HCC) Cationic liposome Transfection

Spin-Peierls Instability in the Ferromagnetic Heisenberg Ladder

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Chinese Physics Letters 2013年第3期30卷 158-162页

作者： XU Yin-Jie ZHAO Hui CHEN Yu-Guang yan yong-hong Key Laboratory for Advanced Microstructure Materials of the Ministry of Education and Department of Physics Tongji UniversityShanghai 200092 Department of Physics Shaoxing UniversityShaoxing 312000

A two-leg S=1/2 spin ladder with ferromagnetic rung coupling is investigated to reveal the phase transition between the Haldane and columnar dimer *** elastic lattice with the elastic force K is introduced into the system,which induces unstable spin chains towards the spontaneous *** the rung coupling is strong enough,the dimerization along the legs is suppressed and the spin ladder undergoes a phase *** dimerization amplitude is calculated self-consistently by the density-matrix renormalization group *** determine the phase transition boundary,the spin gap,the columnar dimer order parameter and the block-block entanglement entropy are *** results show that the phase boundary between the columnar dimer phase and Haldane phase follows the power law J_(t)-K^(-α).

关键词： transition. method. dimer

Research on casing deformation prevention technology based on cementing slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： yan yan Meng Cai Wen-Hai Ma Xiao-Chuan Zhang Li-hong Han yong-hong Liu State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of Mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CNPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cement slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cement sheath was firstly analyzed by discrete element method, and the effect of hollow particles in cement on casing deformation was investigated by laboratory experiment method. Finally, field test was carried out to verify the improvement effect of the casing deformation based on cement slurry modification. The results show that the formation displacement can be absorbed effectively by hollow particles inside the cement transferring the excessive deformation away from casing. The particles in the uncemented state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cement reaches 1:4. According to the field test feedback, the method based on optimization of cement slurry can effectively reduce the risk of casing deformation, and the recommended range of hollow microbeads content in the cement slurry is between 15% and 25%.

关键词： Cement slurry Hollow ceramsite Casing deformation Formation slip Field test

Heat Stress Upregulates the Expression of TLR4 and Its Alternative Splicing Variant in Bama Miniature Pigs

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Journal of Integrative Agriculture 2014年第11期13卷 2479-2487页

作者： JU Xiang-hong XU Han-jin yong yan-hong AN Li-long XU Ying-mei JIAO Pei-rong LIAO Ming Department of Veterinary Medicine Guangdong Ocean University Key Laboratory of Animal Disease Control and Prevention Ministry of Agriculture/College of Veterinary MedicineSouth China Agricultural University Department of Animal Science Guangdong Ocean University

Alternative splicing is a cellular mechanism in eukaryotes that results in considerable diversity ofgene products. It plays an important role in several diseases and cellular signal regulation. Heat stress is a major factor that induces immunosuppression in pigs. Little is known about the correlation between alternative splicing and heat stress in pigs. Therefore, this study aimed to clone, sequence and quantify the alternative splicing variant of toll-like receptor 4 （TLR4） in Bama miniature pigs （Sus scrofa domestica） following exposure to heat stress. The results showed that the second exon of TLR4 was spliced and 167 bp shorter in the alternative splicing variant, and the protein was putatively identified as a type of truncated membrane protein consisting of extramembrane, transmembrane and intramembrane regions lacking a signal peptide. Further, it was not a non- classical secretory protein. Five potential reference genes were screened for their potential as reliable standards to quantify the expression of TLR4 alternative spliced variants by real-time quantitative reverse-transcriptase polymerase chain reaction （qRT-PCR）. The stability of these reference genes was ranked using the geNorm and NormFinder programs, and ribosomal protein L4 （RPL4） and TATA box-binding protein （TBP） were found to be the two genes showing the most stable expression in the in vitro cultured peripheral blood mononuclear ceils （PBMCs） during heat shock. The mRNA level of the TLR4 gene （both classical and spliced） in stressed pigs increased significantly （P〈0.05）. Further, the expression levels of the alternative spliced variant of TLR4 （TLR4-ASV） showed a 2-3 folds increase in heat-stressed PBMCs as compared to control pigs. The results of the present study suggested that heat shock might modulate the host immune response by regulating the expressions of TLR4 and its alternative splicing variant.

关键词： altemative splicing variant Bama miniature pig toll-like receptor 4 heat stress

Low-cycle fatigue behavior of solutionized and aged WE43 magnesium alloys at room temperature

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Journal of Magnesium and Alloys 2024年第6期12卷 2284-2297页

作者： yong Cai Jianxiong Wei hong yan Yipeng Chen Rongshi Chen School of Materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China

The low-cycle fatigue behavior of solutionized(T4)and aged(T6)WE43 magnesium alloys was studied at room *** total strain amplitudes(△ε_(t)/2)were 0.4%,0.5%,0.6%,0.7%and 1.0%.Detailed microstructure evolution was characterized by scanning electron microscope(SEM),electron backscattered diffraction(EBSD)and transmission electron microscopy(TEM).The results showed that plastic strain amplitude decreased with the increasing cycle number in T4 alloy,which is due to the dense persistent slip bands(PSBs)and dynamic precipitates hinderingdislocation *** contrast,the plastic strain amplitude increases gradually in T6 alloy,which is attributed to the enhanced activation of pyramidal *** low-cycle fatigue life of T6 alloy with larger fatigue ductility coefficient is longer than that of T4 *** Coffin-Manson model can accurately predict the fatigue life of T4 and T6 alloys compared to Jahed-Varvani(JV)energy *** T4 alloy,the fatigue damage mechanism was dominated by basal *** T6 alloy,the enhanced pyramidal slip plays an important role to accommodate plastic deformation.

关键词： Low-cycle fatigue WE43 alloy Cyclic hardening/softening JV model Dislocation

Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI Bao-ping FAN hong-yan WANG Guan-nan RAO Xi GE Weifeng SHAO Xiao-yan LIU yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

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重庆商场建筑能耗调查与节能设计分析

重庆建筑大学学报 2005年第4期27卷 33-36页

作者：杨璐严永红河南工业大学土木建筑学院郑州450052 重庆大学建筑城规学院重庆400045

为了探讨公共建筑的节能设计问题,选择重庆市具有代表性的商场建筑作为研究对象,实际调查十二家商场实际运营中的建筑能耗值;根据调查结果,分析了商场建筑的能耗构成与特点,以及高运营能耗结果产生的原因;根据重庆地域气候与环境特点,... 详细信息

为了探讨公共建筑的节能设计问题,选择重庆市具有代表性的商场建筑作为研究对象,实际调查十二家商场实际运营中的建筑能耗值;根据调查结果,分析了商场建筑的能耗构成与特点,以及高运营能耗结果产生的原因;根据重庆地域气候与环境特点,提出贯彻综合节能的思想,以及利用气候资源、运用适宜技术来达到节能目的的建筑设计策略。

关键词：大中型商场建筑能耗节能设计

High-order Soliton Matrix for the Third-order Flow Equation of the Gerdjikov-Ivanov Hierarchy Through the Riemann-Hilbert Method

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 358-378页

作者： Jin-yan ZHU yong CHEN School of Mathematical Sciences Shanghai Key Laboratory of Pure Mathematics and Mathematical PracticeEast China Normal UniversityShanghai 200062China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The Gerdjikov-Ivanov(GI)hierarchy is derived via recursion operator,in this article,we mainly investigate the third-order flow GI *** the framework of the Riemann-Hilbert method,the soliton matrices of the third-order flow GI equation with simple zeros and elementary high-order zeros of Riemann-Hilbert problem are constructed through the standard dressing *** advantage of this result,some properties and asymptotic analysis of single soliton solution and two soliton solution are discussed,and the simple elastic interaction of two soliton are *** with soliton solution of the classical second-order flow,we find that the higher-order dispersion term affects the propagation velocity,propagation direction and amplitude of the ***,by means of a certain limit technique,the high-order soliton solution matrix for the third-order flow GI equation is derived.

关键词： Gerdjikov-Ivanov hierarchy third-order flow GI equation Riemann-Hilbert method high-order soliton