检索结果-南通市图书馆

Ptip safeguards the epigenetic control of skeletal stem cell quiescence and potency in skeletogenesis

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2024年第13期69卷 2099-2113页

作者： Jianfei liang Jing Wang Bingdong sui Yibo Tong Jihua Chai Qin Zhou Chenxi Zheng hao Wang liang Kong haojian Zhang Yi Bai State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyTaikang Center for Life and Medical SciencesWuhan UniversityWuhan 430079China Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research College of StomatologyXi’an Jiaotong UniversityXi’an 710004China Department of Implant Dentistry College of StomatologyXi’an Jiaotong UniversityXi’an 710004China State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyShaanxi International Joint Research Center for Oral DiseasesCenter for Tissue EngineeringSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Oral and Maxillofacial SurgerySchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China Department of Hematology Zhongnan HospitalWuhan UniversityWuhan 430079China Frontier Science Center for Immunology and Metabolism Medical Research InstituteWuhan UniversityWuhan 430079China Taikang Center for life and Medical Sciences Wuhan UniversityWuhan 430079China

Stem cells remain in a quiescent state for long-term maintenance and preservation of potency;this process requires fine-tuning regulatory *** this study,we identified the epigenetic landscape along the developmental trajectory of skeletal stem cells(SSCs)in skeletogenesis governed by a key regulator,Ptip(also known as Paxip1,Pax interaction with transcription-activation domain protein-1).Our results showed that Ptip is required for maintaining the quiescence and potency of SSCs,and loss of Ptip in type II collagen(Col2)^(+)progenitors causes abnormal activation and differentiation of SSCs,impaired growth plate morphogenesis,and long bone *** also found that Ptip suppressed the glycolysis of SSCs through downregulation of phosphoglycerate kinase 1(Pgk1)by repressing histone H3 lysine 27 acetylation(H3K27ac)at the promoter ***,inhibition of glycolysis improved the function of SSCs despite Ptip *** the best of our knowledge,this is the first study to establish an epigenetic framework based on Ptip,which safeguards skeletal stem cell quiescence and potency through metabolic *** framework is expected to improve SSC-based treatments of bone developmental disorders.

关键词： Skeletal stem cells Bone development Epigenetics Ptip Glycolysis

A Practical Predefined-Time Stability Criterion and Its Application to Uncertain Nonlinear Systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2024年

作者： XU hao YU Dengxiu sui Shuai XU Bowen CHEN C.L.Philip Unmanned System Research Institute Northwestern Polytechnical University College of Science Liaoning University of Technology School of Artificial Intelligence Optics and Electronics Northwestern Polytechnical University School of Computer Science and Engineering South China University of Technology and Pazhou Lab

In this paper, the singularity-free predefined-time fuzzy adaptive tracking control problem is studied for non-strict feedback(NSF) nonlinear systems considering mismatched external disturbances. An innovative practical predefined-time stability(PPTS) criterion is proposed to provide the theoretical basis for subsequent control design. Compared to the existing predefined-time stability(PTS) criterion, this criterion has a broader application range and can solve the control design issues of nonlinear systems with system uncertainties. Fuzzy logic systems(FLSs) are employed to identify unknown nonlinear functions. Based on the backstepping control technology, a singularity-free predefined-time control(PTC) design method is proposed, in which the hyperbolic tangent function is utilized to avoid the singular problem, and the nature of fuzzy basis function is adopted to resolve the algebraic loop problem. The PPTS of the closed-loop NSF nonlinear system is proven with the Lyapunov theory and the proposed PPTS criterion. Ultimately, the efficiency of the presented PTC design method is verified by several sets of simulations on a single link manipulator system.

关键词：

基于全局与序列混合变分Transformer的多样化图像描述生成方法

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

电子学报 2024年第4期52卷 1305-1314页

作者：刘兵李穗刘明明刘浩中国矿业大学计算机科学与技术学院江苏徐州221116 矿山数字化教育部工程研究中心江苏徐州221116

多样化图像描述生成已成为图像描述领域研究热点.然而,现有方法忽视了全局和序列隐向量之间的依赖关系,严重限制了图像描述性能的提升.针对该问题,本文提出了基于混合变分Transformer的多样化图像描述生成框架.具体地,首先构建全局与序... 详细信息

多样化图像描述生成已成为图像描述领域研究热点.然而,现有方法忽视了全局和序列隐向量之间的依赖关系,严重限制了图像描述性能的提升.针对该问题,本文提出了基于混合变分Transformer的多样化图像描述生成框架.具体地,首先构建全局与序列混合条件变分自编码模型,解决全局与序列隐向量之间依赖关系表示的问题.其次,通过最大化条件似然推导混合模型的变分证据下界,解决多样化图像描述目标函数设计问题.最后,无缝融合Transformer和混合变分自编码模型,通过联合优化提升多样化图像描述的泛化性能.在MSCOCO数据集上实验结果表明,与当前最优基准方法相比,在随机生成20和100个描述语句时,多样性指标m-BLEU(mutual overlap-Bilingual Evaluation Understudy)分别提升了4.2%和4.7%,同时准确性指标CIDEr(Consensus-based Image Description Evaluation)分别提升了4.4%和15.2%.

关键词：图像理解图像描述变分自编码隐嵌入多模态学习生成模型

Engineered AAV13 variants with enhanced transduction and confined spread

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2024年第4期45卷 781-790页

作者： Neng-Song Luo Yu-Xiang Cai Zeng-Peng Han Xiao-Kai sui Wen-Jia Yuan Zi-lian Zhang hao-Dong Guo Jie Wang Kun-Zhang lin Fu-Qiang Xu Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubei 430074China Shenzhen Key Laboratory of Viral Vectors for Biomedicine Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanHubei 430071China Key Laboratory of Quality Control Technology for Virus-Based Therapeutics Guangdong Provincial Medical Products AdministrationNMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal ProductsBrain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China University of Chinese Academy of Sciences Beijing 100049China Zhongnan Hospital Wuhan UniversityWuhanHubei 430072China Brain Case Biotechnology Co. Ltd.ShenzhenGuangdong 518107China College of life Sciences Wuhan UniversityWuhanHubei 430072China Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031China

Precise targeting of specific regions within the central nervous system(CNS)is crucial for both scientific research and gene therapy in the context of brain ***-associated virus 13(AAV13)is known for its restricted diffusion range within the CNS,making it an ideal choice for precise labeling and administration within small brain ***,AAV13 mediates relatively low expression of target ***,we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction *** first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 *** then inserted the 7m8 peptide,known to enhance cell transduction,into positions 587/588 and 585/586 of the AAV13 capsid,resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8,*** found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13,while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice,with AAV13-587-7m8 infection retaining a limited spread *** modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.

关键词： Adeno-associated virus 13 AAV13-YF AAV13-587-7m8 AAV13-585-7m8 transduction efficiency

基于条件变分推断与内省对抗学习的多样化图像描述生成

在线全文

学校读者我要写书评

暂无评论

电子学报 2024年第7期52卷 2219-2227页

作者：刘兵李穗刘明明刘浩中国矿业大学计算机科学与技术学院江苏徐州221116 矿山数字化教育部工程研究中心江苏徐州221116

现有多样化图像描述生成方法受到隐空间表示能力和评价指标制约,很难同时兼顾描述生成的多样性和准确性.为此,本文提出了一种新的多样化图像描述生成模型,该模型由一个条件变分推断编码器和一个生成器组成.编码器利用全局注意力学习每... 详细信息

现有多样化图像描述生成方法受到隐空间表示能力和评价指标制约,很难同时兼顾描述生成的多样性和准确性.为此,本文提出了一种新的多样化图像描述生成模型,该模型由一个条件变分推断编码器和一个生成器组成.编码器利用全局注意力学习每个单词的隐向量空间,以提升模型对描述多样化的建模能力.生成器根据给定图像和序列隐向量生成多样化的描述语句.同时,引入内省对抗学习的思想,条件变分推断编码器同时作为鉴别器来区分真实描述和生成的描述,赋予模型自我评价生成的描述语句的能力,克服预定义评价指标的局限性.在MSCOCO数据集上的实验表明,与传统方法相比,在随机生成100个描述语句时,多样性指标mBLEU(mutual overlap-Bilingual Evaluation Understudy)提升了1.9%,同时准确性指标CIDEr(Consensus-based Image Description Evaluation)显著提升了7.5%.与典型多模态大模型相比,所提出方法在较小参数量的条件下更适用于生成多样化的陈述性描述语句.

关键词：图像描述变分推断对抗学习隐嵌入多模态学习生成模型

同方期刊数据库

Self-assembling anchored film basing on two tetrazole derivatives for application to protect copper in sulfuric acid environment

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第17期52卷 63-71页

作者： Yujie Qiang hao li xijian Lan Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

Two tetrazole compounds(BTA,BTTA)self-assembled on copper substrate and their inhibition effect toward copper corrosion in 0.5 M H2SO4 was evaluated through atomic force microscopy(AFM),scanning electron microscopy(SEM),weight loss measurement along with electrochemical techniques including electrochemical impedance spectroscopy(EIS)and potentiodynamic *** indicate that BTTA can provide superior inhibition performance to BTA,and the highest inhibition efficiency values of 96.3%(BTA)and 99.8%(BTTA)were achieved respectively at 2 *** tetrazole inhibitor films follow Langmuir model concerning both physical and chemical adsorption,which can be verified by Xray photoelectronic spectroscopy(XPS)***,the negative value of adsorption free energy infers a spontaneous adsorption process of these tetrazole compounds on Cu *** dynamics(MD)simulation reveals stronger multiple anchor adsorption of BTTA molecules than BTA because of the existence of S atom.

关键词： Copper Corrosion inhibitor Adsorption Anticorrosion MD simulation

在线全文

学校读者我要写书评

暂无评论

SD大鼠股骨慢性骨髓炎模型构建与评价

海军军医大学学报 2024年第5期45卷 552-557页

作者：孙智隋钧皓章浩海军军医大学(第二军医大学)第一附属医院创伤骨科上海200433

目的建立并评价SD大鼠股骨慢性骨髓炎动物模型。方法取雄性SD大鼠24只,暴露大鼠右股骨髁间沟,用电钻于股骨髁间沟处钻1个直径0.5 mm的小孔直通股骨髓腔,向髓腔内注入50μL细菌密度为1×10^(6)/mL的金黄色葡萄球菌悬液,用无菌骨蜡密封孔... 详细信息

目的建立并评价SD大鼠股骨慢性骨髓炎动物模型。方法取雄性SD大鼠24只,暴露大鼠右股骨髁间沟,用电钻于股骨髁间沟处钻1个直径0.5 mm的小孔直通股骨髓腔,向髓腔内注入50μL细菌密度为1×10^(6)/mL的金黄色葡萄球菌悬液,用无菌骨蜡密封孔洞。观察大鼠术后行为学、切口愈合、体温、病灶大体感染等情况;术后2、4、8周,取大鼠造模股骨周围软组织进行细菌培养,采用小动物CT机观察股骨影像学表现;术后2、8周,取造模股骨组织制成病理学切片,进行H-E染色、吉姆萨染色及Masson染色。结果造模后大鼠右后肢勾悬、不能负重,术后第10天左右手术切口完全愈合,第12天恢复至正常活动水平,第15天以后活动水平稍有下降。术后大鼠体温逐渐升高,感染部位局部红肿;2周以后体温虽下降,但仍然高于正常体温,部分大鼠右膝关节局部出现包块;4周后所有大鼠均有局部红肿和体温升高等症状。大鼠造模股骨周围软组织细菌培养可见均匀分布的金黄色葡萄球菌菌落,且随时间延长而增多。小动物CT机检查结果显示,术后8周大鼠造模股骨髓腔内炎症反应明显,骨质破环累及骨皮质全层,死骨形成并伴有新骨生成。造模股骨组织病理学分析结果显示,术后2周骨髓腔内有大量炎症细胞浸润,炎症局限于骨髓腔内,可见皮质骨中胶原纤维连续排列,组织内含有大量的金黄色葡萄球菌;术后8周炎症迁延,皮质骨中胶原纤维大量断裂,皮质骨大量破坏且有窦道与外界相连,组织内金黄色葡萄球菌数量进一步增多。结论SD大鼠股骨慢性骨髓炎模型造模成功,可较好地模拟临床骨髓炎病理生理变化,具有高度可复制性。

关键词：慢性股骨骨髓炎动物模型金黄色葡萄球菌行为学病理学

基于数据抓取的开放教育教师多维度画像构建策略

在线全文

学校读者我要写书评

暂无评论

成人教育 2024年第7期44卷 50-60页

作者：李雨朦隋皓辰国家开放大学学生工作与教师发展部北京100039 国家开放大学组织部/人事处北京100039

新时代教师队伍建设是教育现代化的重要内容和前提。考虑到开放教育教师的丰富内涵,基于大数据分析对其进行适应性的、多元的、发展的教师数字画像时必须结合职责定位。研究以探索开放教育教师多维度画像实现路径为目的,从画像目标确立... 详细信息

新时代教师队伍建设是教育现代化的重要内容和前提。考虑到开放教育教师的丰富内涵,基于大数据分析对其进行适应性的、多元的、发展的教师数字画像时必须结合职责定位。研究以探索开放教育教师多维度画像实现路径为目的,从画像目标确立、数据采集与预处理、模型构建、标签体系构建、画像输出与评估、精准应用七个环节系统探讨了开放教育教师画像的必要性、可行性与实施构想,构建了双维个体标签体系,并提出教师画像在职业生涯规划、考核评价、循证管理、专业发展规划等场景下的应用设想。研究旨在帮助构建符合高质量开放教育教师成长规律的多维度教师画像,为新时代教师评价和发展支持体系的建立提供参考。

关键词：教师画像开放教育多维度画像应用场景数据抓取

在线全文

学校读者我要写书评

暂无评论

非饱和土基坑抗隆起稳定性研究

岩土工程学报 2024年第8期46卷 1762-1767,1790页

作者：张常光隋建浩范家燊徐灏长安大学建筑工程学院陕西西安710061 成都理工大学地质灾害防治与地质环境保护国家重点实验室四川成都610059

鉴于基坑周围土体常处于非饱和状态以及挡墙位移多发生绕墙底RB模式转动,首先采用非饱和土双应力状态变量理论推导墙底条形基础单侧滑动的承载力与RB位移模式下墙-土整体下滑时的竖向抗滑力,继而基于极限平衡法提出均布/线性吸力下非饱... 详细信息

鉴于基坑周围土体常处于非饱和状态以及挡墙位移多发生绕墙底RB模式转动,首先采用非饱和土双应力状态变量理论推导墙底条形基础单侧滑动的承载力与RB位移模式下墙-土整体下滑时的竖向抗滑力,继而基于极限平衡法提出均布/线性吸力下非饱和土基坑抗隆起安全系数的求解过程,最后对比文献理论解答进行基坑工程实例应用与验证和挡墙位移模式探讨。研究表明:本文基坑抗隆起安全系数能反映土体非饱和特性与挡墙RB位移模式,可自然退化为饱和土结果,并得到文献地基承载力模式解答和极限上限法解答的合理性验证;挡墙RB位移模式下的竖向抗滑力小于静止状态下的,对应的基坑抗隆起安全系数亦然;非饱和土基坑若按忽略非饱和强度特性的饱和土基坑简化计算,得到的基坑抗隆起安全系数偏于保守。

关键词：基坑抗隆起非饱和土竖向抗滑力基质吸力