检索结果-南通市图书馆

Microstructure evolution and stress rupture properties of K4750 alloys with various B contents during long-term aging

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第14期73卷 108-115页

作者： Xiaoxiao Li Meiqiong Ou Min Wang xiang dong zha Yingche Ma Kui Liu Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

The relationship among B content,microstructure evolution and stress rupture properties of K4750 alloy during long-term aging were *** aging at 800℃for 1000 h,the decomposition degree of MC carbides of K4750 alloys with 0 B,0.007 wt.%B and 0.010 wt.%B were basically identical,which indicated that B has no inhibition on MC carbide decomposition during long-term *** MC carbide decomposition was accompanied by the formation of M_(23)C_(6) carbides and a small number ofηphases,which was controlled by the outward diffusion of C and Ti combined with the inward diffusion of Ni and Cr from theγ*** addition,M_(23)C_(6) carbides in boron-free alloy were in continuous chain and needle-likeηphases were precipitated near them,while M_(23)C_(6) carbides in boron-containing alloys remained in granular distribution and noηphases precipitation around *** B could delay the agglomeration and coarsening of M_(23)C_(6) carbides during long-term aging,which was because the segregation of B at grain boundary retarded the diffusion of alloy elements,thus weakened the local fluctuation of chemical composition near grain *** stress rupture samples of K4750 alloys with various B contents after aging at 800℃for 1000 h were tested at 750℃/380 *** results indicated that the stress rupture properties of bo ron-containing alloys were significantly better than that of boron-free alloy,which could be attributed to the increase of grain boundary cohesion strength and the optimization of M_(23)C_(6) carbide distribution due to the addition of B.

关键词： Nickel-based superalloy Boron additions Long-term aging Grain boundary segregation Stress rupture properties

cDNA cloning,sequence analysis,and recombinant expression of akitonin beta,a C-type lectin-like protein from Agkistrodon acutus

在线全文

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2004年第3期25卷 118-123页

作者： xiang-dong zha1,2,Jing LIU1,Kang-sen XU3 1 School of Life Science,University of Science and Technology,Hefei 230026 School of Life Science,Anhui University,2 Hefei 230039 National Institute for Control of Pharmaceuticals and Biological Products,Beijing 100050,China 3 School of Life Science University of Science and Technology School of Life Science Anhui University National Institute for Control of Pharmaceuticals and Biological Products Beijing 100050 China

AIM: To clone the cDNA of a new member of snake venom C-type lectin-like proteins, to study its structure- function relationships and to achieve its recombinant production. METHODS: PCR primers were designed based on the homology and cDNA was amplified by RT-PCR using total RNA from snake venom gland as the template. The PCR products were cloned into the plasmid pGEM-T and sequenced. The deduced protein sequence was analyzed with some bioinformatic programs. A recombinant expression plasmid was constructed using pBAD- TOPO as vector and transformed into *** TOP10 competent cells. RESULTS: A novel cDNA sequence encod- ing akitonin β was found and accepted by GenBank (accession number AF387100). Akitonin β consists of a typical carbohydrate recognition domain (CRD) of C-type lectins, and it is homologous with other snake venom C-type lectin-like proteins. It was predicted to be a platelet antagonist. Upon induction with arabinose rAkitonin β express- ing in E coli was achieved at a high level (superior to 150 mg/L). The recombinant fusion protein exhibited inhibitory activities on rat platelet aggregation in vitro. CONCLUSION: A new member of snake venom C-type lectin-like proteins was discovered and characterized, and an efficient recombinant expression system was estab- lished for its production.

关键词： snake venoms cDNA akitonin C-type lectin-like proteins recombinant proteins structure- activity relationship

AZD1775 synergizes with SLC7A11 inhibition to promote ferroptosis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Life Sciences 2025年第1期 204-218页

作者： Chen Xiong Hong Ling Yingdan Huang Hanzhi dong Bangxiang Xie Qian Hao xiang Zhou Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences Fudan University Department of Oncology Shanghai Medical CollegeFudan University Department of Breast Surgery Fudan University Shanghai Cancer CenterFudan University Department of Oncology First Affiliated Hospital of Nanchang University Beijing Institute of Hepatology Beijing Youan HospitalCapital Medical University Beijing Engineering Research Center for Precision Medicine and Transformation of Hepatitis and Liver Cancer Key Laboratory of Breast Cancer in Shanghai Fudan University Shanghai Cancer CenterFudan University Shanghai Key Laboratory of Medical Epigenetics International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology)Institutes of Biomedical SciencesFudan University

Tumor suppressor p53-mediated cell cycle arrest and DNA damage repair may exert cytoprotective effects against cancer therapies, including WEE1 inhibition. Considering that p53 activation can also lead to multiple types of cell death, the role of this tumor suppressor in WEE1 inhibitor-based therapies remains disputed. In this study, we reported that nucleolar stress-mediated p53 activation enhanced the WEE1 inhibitor AZD1775-induced ferroptosis to suppress lung cancer growth. Our findings showed that AZD1775 promoted ferroptosis by blocking cystine uptake, an action similar to that of Erastin. Meanwhile, inhibition of WEE1 by the WEE1 inhibitors or si RNAs induced compensatory upregulation of SLC7A11, which conferred resistance to ferroptosis. Mechanistically, AZD1775 prevented the enrichment of H3K9me3, a histone marker of transcriptional repression, on the SLC7A11 promoter by repressing the expression of the histone methyltransferase SETDB1, thereby enhancing NRF2-mediated SLC7A11 transcription. This finding was also validated using the H3K9me3 inhibitor BRD4770. Remarkably, we found that the nucleolar stress-inducing agent Actinomycin D(Act. D) inhibited SLC7A11 expression by activating p53, thus augmenting AZD1775-induced ferroptosis. Moreover, the combination of AZD1775 and Act. D synergistically suppressed wild-type p53-harboring lung cancer cell growth both in vitro and in vivo. Altogether, our study demonstrates that AZD1775 promotes ferroptosis by targeting cystine uptake but also mediates the adaptive activation of SLC7A11 through the WEE1-SETDB1 cascade and NRF2-induced transcription, and inhibition of SLC7A11 by Act. D boosts the anti-tumor efficacy of AZD1775 by enhancing ferroptosis in cancers with wild-type p53.

关键词：

同方期刊数据库

High-resolution imaging through dynamic scattering media: Iterative optimization based on polarimetric characteristics

在线全文

学校读者我要写书评

暂无评论

Science China Technological Sciences 2025年第1期 82-84页

作者： Meng xiang Kai DENG Tianyu WANG Jinpeng LIU Xue dong Teli XI Fei LIU Xiaopeng SHAO School of Optoelectronic Engineering Xidian University Xi'an Key Laboratory of Computational Imaging National Key Laboratory of Infrared Detection Technologies

High-resolution imaging through randomly dynamic scattered fields and highly scattered walls is an extensively sought-after capability with potential applications in various fields such as underwater imaging, biomedical imaging, and seeing through fog. Numerous methods have been proposed to unscramble object information from degraded scattered images, resulting in considerable improvements in image contrast in degraded scenarios [1].

关键词：

Decentralized fault diagnosis of discrete-event systems with unreliable sensors using linear temporal logic

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第1期 322-341页

作者： Weijie dong Shaoyuan LI xiang YIN Key Laboratory of System Control and Information Processing Ministry of EducationDepartment of Automation Shanghai Jiao Tong University

In this paper,we investigate a decentralized diagnosis problem of a discrete-evnt system(DES) subject to unreliable sensors,where the sensor observations of local diagnosers may be non-deterministic as a result of possible *** studies on decentralized robust diagnosis can only deal with different types of sensor failures separately,e.g.,all sensors suffer from the same type of sensor failures such as intermittent sensor failures or permanent sensor ***,since sensors of different local diagnosers may face different external environments and have different internal characteristics,sensors corresponding to different local diagnosers may also have their own fault *** this paper,we propose a flexible framework of decentralized diagnosis for DES subject to unreliable sensors such that sensors of different local diagnosers are permitted to have different types of sensor *** this end,we extend the existing decentralized diagnosis framework to the case where there exist common sensors broadcasting their observations to all local *** apply linear temporal logic(LTL) to constrain infinite behaviors of private sensors of local diagnosers and common ***,a new notion of φ-codiagnosability is proposed as the necessary and sufficient condition for the existence of a decentralized diagnoser that works correctly under sensors,satisfying LTL-based sensor ***,we provide an effective approach to verify the φ-codiagnosability.

关键词：

Thrombin-like enzymes from venom gland of Deinagkistrodon acutus:cDNA cloning,mechanism of diversity and phylogenetic tree construc-tion

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmacologica Sinica 2006年第2期27卷 184-192页

作者： xiang-dong zha~(2,3,7) He-sheng HUANG~(4,7) Li-zhi ZHOU~(2,3) Jing LIU~5 Kang-sen XU~6 ~2School of Life Sciences,Anhui University,Hefei 230039,China ~3Anhui Key Laboratory of Eco-Engineering and Bio-techniques,Hefei 230039,China ~4Department of Pharmacology,Anhui Medical University.Hefei 230022,China ~5School of Life Sciences,University of Science and Technology of China,Hefei 230026,China ~6Institute for Control of Pharmaceuticals and Biological Products,Beijing 100050,China SchoolofLifeSciences AnhuiUniversityHefei230039China AnhuiKeyLaboratoryofEco-EngineeringandBio-techniques Hefei230039China DepartmentofPharmacology AnhuiMedicalUniversityHefei230022China

Aim:To clone cDNAs of thrombin-like enzymes(TLEs)from venom gland ofDeinagkistrodon acutus and analyze the mechanisms by which their structuraldiversity ***:Reverse transcription-polymerase chain reaction andgene cloning techniques were used,and the cloned sequences were analyzed byusing bioinformatics ***:Novel cDNAs of snake venom TLEs *** possibilities of post-transcriptional recombination and horizontalgene transfer are discussed.A phylogenetic tree was ***:The cDNAs of snake venom TLEs exhibit great *** are severaltypes of structural *** variations may be attributable to certainmechanisms including recombination.

关键词： thrombin-like enzymes structural diversity RNA recombination phylogenetic tree

Simulation of dual transponder carrier ranging measurements

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1395-1403页

作者： xiang-yu zha Xiao-jun JIN Zhong-he JIN Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The most dominant error source for microwave ranging is the frequency instability of the oscillator that generates the carrier phase signal. The oscillator noise is very difficult to filter due to its extremely low frequency. A dual transponder carrier ranging method can effectively minimize the oscillator noise by combing the reference phase and the to-and-fro measurement phase from the same single oscillator. This method does not require an accurate time tagging system, since it extracts phases on the same satellite. This paper analyzes the dual transponder carrier ranging system by simulation of the phase measurements with comprehensive error models. Both frequency domain and time domain noise transfer characteristics were simulated to compare them with dual one-way ranging. The simulation results in the two domains conformed to each other and demonstrated that a high level of accuracy can also be achieved by use of the dual transponder carder ranging system, with relatively simple instruments.

关键词： Dual transponder carrier ranging Dual one-way ranging Oscillator noise Transfer characteristic

The youngest X-ray binaries

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2020年第10期20卷 221-228页

作者： xiang-dong Li School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China

Several X-ray binaries(XRBs)have been identified to be associated with supernova remnants(SNRs).Because of the short lifetimes of SNRs,this leaves them to be the youngest known *** small group of binaries provides valuable information on the formation of compact stars under the framework of massive binary *** this paper we review the observational characteristics of these youngest XRBs and discuss their possible implications on the initial conditions of compact stars and their interaction with the companion stars.

关键词： accretion,accretion disks stars:black holes stars:neutron,evolution

Clonal hematopoiesis:a shared risk factor for cardiovascular diseases and tumors

在线全文

学校读者我要写书评

暂无评论

Oncology and Translational Medicine 2024年第1期10卷 35-41页

作者： Ling-Feng zha xiang Cheng Department of Cardiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Hubei Key Laboratory of Biological Targeted Therapy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Hubei Provincial Engineering Research Center of Immunological Diagnosis and Therapy for Cardiovascular Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

Clonal hematopoiesis(CH)is a clonally expanded population of hematopoietic stem cells carrying somatic mutations that differentiate through multilineage hematopoiesis to form terminally differentiated mature hematopoietic cells carrying markers of the clonal *** integral to critical cellular processes such as epigenetic regulation,DNA damage response,and inflammation frequently carry these *** hematopoiesis becomes increasingly prevalent with age and is associated with an increased risk of hematological tumors and some nonhematological *** insights have revealed that the mutations driving CH are not only implicated in hematologic neoplasms but also possess the potential to influence cardiovascular ***,we reviewed up-to-date findings about the roles of CH in cardiovascular diseases and tumors and explored the clinical significance of CH,as well as look forward to future related studies,so as to provide valuable references for future research and clinical practice.

关键词： Cardiovascular diseases Clonal hematopoiesis Tumors