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Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease
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作者 Yinglong Miao Michael S.Wolfe 《Neural Regeneration Research》 SCIE CAS 2025年第1期174-180,共7页
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ... γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general. 展开更多
关键词 Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics NOtCH
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Dietary polyphenols reduced the allergenicity ofβ-lactoglobulin via non-covalent interactions:a study on the structure-allergenicity relationship
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作者 Chi Zhang Qiaozhi Zhang +6 位作者 Huatao Li Zhouzhou Cheng Shiyu Fan Hujun Xie Zhongshan Gao Yan Zhang Linglin Fu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2617-2628,共12页
Studies showed that complexation of polyphenols with milk allergens reduced their immunogenic potential.However,the relationship between structures of polyphenols and their hypoallergenic effects on milk allergens in ... Studies showed that complexation of polyphenols with milk allergens reduced their immunogenic potential.However,the relationship between structures of polyphenols and their hypoallergenic effects on milk allergens in association with physiological and conformational changes of the complexes remain unclear.In this study,polyphenols from eight botanical sources were extracted to prepare non-covalent complexes withβ-lactoglobulin(β-LG),a major allergen in milk.The dominant phenolic compounds bound toβ-LG with a diminished allergenicity were identified to investigate their respective role on the structural and allergenic properties ofβ-LG.Extracts from Vaccinium fruits and black soybeans were found to have great inhibitory effects on the IgE-and IgG-binding abilities ofβ-LG.Among the fourteen structure-related phenolic compounds,flavonoids and tannins with larger MWs and multi-hydroxyl substituents,notably rutin,EGCG,and ellagitannins were more potent to elicit changes on the conformational structures ofβ-LG to decrease the allergenicity of complexedβ-LG.Correlation analysis further demonstrated that a destabilized secondary structure and protein depolymerization caused by polyphenol-binding were closely related to the allergenicity property of formed complexes.This study provides insights into the understanding of structure-allergenicity relationship ofβ-LG-polyphenol interactions and would benefit the development of polyphenol-fortified matrices with hypoallergenic potential. 展开更多
关键词 Cow’s milk allergy Β-LACtOGLOBULIN Protein-polyphenol interaction ALLERGENICItY Conformational structure
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Comparative Study of Genetic Structure and Genetic Diversity betweenWild and Cultivated Populations of Taxus cuspidata,Northeast China
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作者 Dandan Wang Xiaohong Li Yanwen Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期355-369,共15页
Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is... Taxus cuspidata is a rare plant with important medicinal and ornamental value.Aiming at the obvious differences between wild and cultivated populations of T.cuspidata from Northeast China,a total of 61 samples,that is,33 wild yews and 28 cultivated yews were used to analyze the differences and correlations of the kinship,genetic diversity,and genetic structure between them by specific length amplified fragment sequencing(SLAF-seq).Finally,470725 polymorphic SLAF tags and 58622 valid SNP markers were obtained.Phylogenetic analysis showed that 61 samples were classified into 2 clusters:wild populations and cultivated populations,and some wild yews were categorized into the cultivated populations;the genetic diversity analysis showed that the Nei diversity index of wild populations(0.4068)was smaller than that of cultivated populations(0.4414),and the polymorphic information content(PIC)of wild populations(0.2861)was smaller than that of cultivated populations(0.3309).The genetic differentiation analysis showed that the total populations of gene diversity(H_(t))of cultivated and wild populations were respectively 0.8159 and 0.5685,the coefficient of gene differentiation(G_(st))of cultivated and wild populations was respectively 0.3021 and 0.1068,and the gene flow(N_(m))(2.4967)of wild populations was larger than cultivated populations(0.8199).The molecular variance(AMOVA)revealed that inter-population variation accounted for 29.57%of the total genetic variation,while intra-population variation accounted for 70.42% of the total genetic variation(p<0.001),this suggested that the genetic variation in the T.cuspidata is mainly attributed to within-population factors.In conclusion,the genetic distance between geographical ecological groups of wild populations was generally smaller than that of cultivated populations,and the degree of genetic diversity and genetic differentiation was smaller than that of cultivated populations.As evident,the utilization of SLAF-seq technology enables efficient and accurate development of SNP markers suitable for genetic analysis of T.cuspidata species.These developed SNP markers can provide a molecular foundation for T.cuspidata breeding,construction of genetic maps,variety identification,and association analysis of agronomic traits. 展开更多
关键词 t.cuspidata sLAF-seq sNP wild population cultivated population genetic structure
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Systematic Review of Community Type 2 Diabetes Structured Health Education (CT2DSHE)
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作者 Gift Phiri 《Open Journal of Nursing》 2024年第8期377-400,共24页
Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming t... Aim: This paper aims to evaluate disparities of type 2 diabetes structured health education programmes that is utilised within the communities. Design: systematic review, (a type of secondary research design) aiming to summarize the results of prior primary research studies on available evidence Community type 2 diabetes structured education (CT2DSHE). Methods: Research question: Type 2 diabetic structured health education within a community how effective is it? Qualitative Systematic review, defined as a way to get reliable and objective picture of current available evidence on the specific topic—(CT2DSHE), (Denscombe, 2021) through reflexivity synthesis of available data as an example. This is valuable in time constraints such as project assignments that must be met within specific time and also to bring together available evidence together [1]. Results: This review has shown that CT2DSHE is effective with seven out of the eleven authors supporting, three authors against and one was neutral, further showed that knowledge and skills acquired can last longer with patient activation improved among T2DM patients ideal for sustaining their self-management of T2DM. Conclusion: This research provides suggestive answers to the research question: “Type 2 diabetic structured health education within a community how effective is it?”, This has demonstrated CT2DSHE effectiveness in knowledge acquisition and improving T2DM awareness among T2DM patients, whilst evidencing long effects beyond the study times of 3 - 9 months period in relation to patient activation. Also Identified diabetes education self-management on newly diagnosed (DESMOND) patient as CT2DSHE program for recommendation. Patient or Public Contribution: This work aspires to contribute to CT2DSHE in these areas;Influencing policy decision-making for community diabetes care within the UK and world at large., Contributing to already vast knowledge on diabetes self-management and reasons why?, Influencing educators on how CT2DSHEP are designed, delivered by putting the patient at the Centre and bringing different perspectives on CT2DSHEP in one place that is serving users time of having to consult several resources especially busy clinicians [2] [3]. 展开更多
关键词 Community Health EDUCAtION EFFECtIVENEss Impact structured and Planned type 2 Diabetes (t2DM)
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 scale-symmetric theory tension Cosmology Coupling Constants Parameters σ8 and s8 Largest Cosmic structures Dark Energy supernova Explosion Cyclic Universe
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Evaluation of Technical Education by Using a Modern Structured MOODLE Laboratory Course, in Relation to Recent Data
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作者 Gerasimos Vlassopoulos George Albert Karikas +4 位作者 Efstathia Papageorgiou Ioannis Psaromiligkos Niki Giannouli Pigi Vlassopoulou Petros Karkalousos 《Journal of Intelligent Learning Systems and Applications》 2024年第3期316-339,共24页
E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo... E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant. 展开更多
关键词 Information and Communication technologies (ICt) Distance Learning E-Learning students Opinions Education in Greece I.C.t. in Greece stUDENts Pupils Adults Adult students MOODLE MOOC (V.H.s.) Vocational High schools (s.H.V.t.) schools of Higher Vocational training VOCAtIONAL Profession Interactive Lessons Courses training Laboratory Course secondary Education Automotive systems Car systems
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Allozyme Diversity and Population Genetic Structure of Three Medicinal Epimedium Species from Hubei 被引量:4
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作者 徐艳琴 李作洲 +1 位作者 王瑛 黄宏文 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期56-71,共16页
Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chi... Three Epimedium species, E. pubescens Maxim., E. sagittatum (Sieb. & Zucc.) Maxim., and E. wushanense T. S. Ying, which are sympatrically distributed in the western Hubei Province, have been used in traditional Chinese medicine (TCM) for about 2,000 years. Genetic variability and population genetic structure of 11 natural populations of these Epimedium species were investigated using isoelectric focusing in thin-layer polyacrylamide slab gels. Of the 22 enzyme systems prescreened, six coding for 13 loci and 45 alleles were resolved, which were used for analyzing genetic diversity and population structure at both intraspecific and interspecific levels. The results showed that: l) high levels of genetic diversity were observed in all three species (A = 2.6-3.2, P = 69.2%-84.6%, Ho= 0.274-0.377, HE= 0.282-0.369), which were higher than that of other herbaceous and aulmal-pollinated species with similar life-history characteristics; 2) there was significant deviation from Hardy-Weinberg Equilibrium, with one half of the loci showing heterozygote excess and the other homozygote excess, in all populations, suggesting the complicated breeding system of Epimedium species; 3) the low level of intraspecific and interspecific genetic differentiation (GST= 0.0246-0.0409 and 0.0495-0.1213, respectively) indicated a high level of gene flow among populations and close genetic relationship among the three species; and 4) UPGMA cluster analysis further showed that E. pubescens was more closely related to E. sagittatum than to E. wushanense, which was in good agreement with the morphological characters and the recent phylogenetic analysis of these species. On the basis of these results, it was concluded that the mixed breeding system, long-lived perennial life form, ancient evolutionary history, and seed dispersal by ants in Epimedium are responsible for the genetic variation and population structure of these species. 展开更多
关键词 Epimedium pubescens Maxim. E. sagittatum sieb. Zucc.) Maxim. E. wushanense t. s. Ying ALLOZYME genetic diversity population structure
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Numerical simulation of rock pore-throat structure effects on NMR T_2 distribution 被引量:4
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作者 王克文 李宁 《Applied Geophysics》 SCIE CSCD 2008年第2期86-91,共6页
We built a three-dimensional irregular network model which can adequately describe reservoir rock pore-throat structures. We carried out numerical simulations to study the NMR T2 distribution of water-saturated rocks.... We built a three-dimensional irregular network model which can adequately describe reservoir rock pore-throat structures. We carried out numerical simulations to study the NMR T2 distribution of water-saturated rocks. The results indicate that there is a good correlation between T2 distribution and the pore radius frequency histogram. The total T2 distribution can be partitioned into pore body and pore throat parts. The effect of parameters including throat radius, pore-throat ratio, and coordination number of the micro- pore structure on the T2 distribution can be evaluated individually. The result indicates that: 1 ) with the increase of the pore throat radius, the T2 distribution moves toward longer relaxation times and its peak intensity increases; 2) with the increase of the pore-throat ratio, the T2 distribution moves towards longer T2 with the peak intensity increasing and the overlap between pore body T2 and pore throat T2 decreasing; 3) With the increase of connectivity, the short T2 component increases and peak signal intensity decreases slightly. 展开更多
关键词 Network model NMR t2 distribution Pore structure Microstructure modeling
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A study on deep structure using teleseismic receiver function in Western Yunnan 被引量:16
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作者 贺传松 王椿镛 吴建平 《地震学报》 CSCD 北大核心 2004年第3期238-246,共9页
s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, i... s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mo-bile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here. 展开更多
关键词 接收函数 反演 s波速度结构 构造关系
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A Rhetorical Structure Theory Based Approach to Texture Coherence in Chinese EFL Learners' Argumentative Writing
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作者 李洪坤 廖志华 《海外英语》 2015年第16期201-204,共4页
Based on Rhetorical Structure Theory(RST),this study intends to investigate into the typical features of rhetorical relations in Chinese EFL learners’argumentative writing and their relationship with writing quality.... Based on Rhetorical Structure Theory(RST),this study intends to investigate into the typical features of rhetorical relations in Chinese EFL learners’argumentative writing and their relationship with writing quality.A set of 60 essays(30 with the highest scores and another 30 with the lowest scores)were drawn from SWECCL(Spoken and Written English Corpus of Chinese Learners).These essays were then cut into elementary discourse units and manually annotated with rhetorical relations.Research findings show that there is no significant difference in terms of the total numbers and types of rhetorical relations between the two proficiency groups.However,comparisons of the rhetorical relations both at the intra-paragraph and at the inter-paragraph level indicate statistical differences between the two groups. 展开更多
关键词 RHEtORICAL structure tHEORY RHEtORICAL RELAtIONs t
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Analysis of the Structure of Shakespeare's Sonnets
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作者 李鹏 《科技视界》 2014年第2期205-206,共2页
The sonnet is a kind of lyrics with restrict forms which cannot depart from the contents. Shakespeare's sonnets are like a valuable flower blossoming in the England poetry garden during the age of Renaissance and ... The sonnet is a kind of lyrics with restrict forms which cannot depart from the contents. Shakespeare's sonnets are like a valuable flower blossoming in the England poetry garden during the age of Renaissance and a bright pearl sparkling in the world's poetry treasury. This paper will analyze his sonnets from the perspective of the structure and then interpret the meanings behind those words, which can demonstrate the importance of the connection between the forms and the contents. 展开更多
关键词 英语教学 教学方法 阅读教学 课外阅读
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Effect of C/S Ratio on Morphology and Structure of Hydrothermally Synthesized Calcium Silicate Hydrate 被引量:11
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作者 何永佳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期770-773,共4页
The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics... The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of (002), (110) and (020) decreased, the d-spacing of (200) increased, and the d-spacing of (310) varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased. 展开更多
关键词 calcium silicate hydrate C/s ratio MORPHOLOGY structure hydrothermal synthesis
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Nuclear magnetic resonance T_2 spectrum:multifractal characteristics and pore structure evaluation 被引量:20
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作者 Yan Jian-Ping He Xu +4 位作者 Geng Bin Hu Qin-Hong Feng Chun-Zhen Kou Xiao-Pan Li Xing-Wen 《Applied Geophysics》 SCIE CSCD 2017年第2期205-215,322,共12页
Pore structure characteristics are important to oil and gas exploration in complex low-permeability reservoirs. Using multifractal theory and nuclear magnetic resonance (NMR), we studied the pore structure of low-pe... Pore structure characteristics are important to oil and gas exploration in complex low-permeability reservoirs. Using multifractal theory and nuclear magnetic resonance (NMR), we studied the pore structure of low-permeability sandstone rocks from the 4th Member (Es4) of the Shahejie Formation in the south slope of the Dongying Sag. We used the existing pore structure data from petrophysics, core slices, and mercury injection tests to classify the pore structure into three categories and five subcategories. Then, the T2 spectra of samples with different pore structures were interpolated, and the one- and three-dimensional fractal dimensions and the multifractal spectrum were obtained. Parameters a (intensity of singularity) andf(a) (density of distribution) were extracted from the multifractal spectra. The differences in the three fractal dimensions suggest that the pore structure types correlate with a andf(a). The results calculated based on the multifractal spectrum is consistent with that of the core slices and mercury injection. Finally, the proposed method was applied to an actual logging profile to evaluate the pore structure of low-permeability sandstone reservoirs. 展开更多
关键词 NMR t2 spectrum MULtIFRACtAL INtERPOLAtION pore structure PERMEABILItY sANDstONE
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A welding document management software package based on a Client/Server structure 被引量:4
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作者 魏艳红 杨春利 王敏 《China Welding》 EI CAS 2003年第1期72-77,共6页
According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software pa... According to specifications for Welding Procedure Qualification of ASME IX Section and Chinese code, JB 4708 2000, a software package for managing welding documents has been rebuilt. Consequently, the new software package can be used in a Limited Area Network (LAN) with 4 different levels of authorities for different users. Therefore, the welding documents, including DWPS (Design for Welding Procedure Specifications), PQRs (Procedure Qualification Records) and WPS (Welding Procedure Specifications) can be shared within a company. At the same time, the system provides users various functions such as browsing, copying, editing, searching and printing records, and helps users to make decision of whether a new PQR test is necessary or not according to the codes above as well. Furthermore, super users can also browse the history of record modification and retrieve the records when needed. 展开更多
关键词 C/s structure welding procedure qualification DAtABAsE LAN
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A study on deep structure using teleseismic receiver function in Western Yunnan 被引量:2
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作者 HE Chuan-song(贺传松) +3 位作者 WANG Chun-yong(王椿镛) WU Jian-ping(吴建平) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期262-271,共10页
s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, i... s Western Yunnan is located at the boundary of collision or underthrusting zone of Eurasian plate and is influenced by many times tectonic movements. With very complex geological environment and tectonic background, it is one of the seismically active areas. In the paper, the teleseismic records were selected from 16 national, local and mo-bile stations, including 4 very-wide-band mobile stations of PASSCAL. And nearly 2 000 receiver functions were extracted. Two measuring lines are 650 km and 450 km, respectively and across some major tectonic units in Western Yunnan. It is indicated that Nujiang might be a seam characterized by underthrusting. The western and eastern boundaries of Sichuan-Yunnan rhombus block, i.e., Honghe and Xiaojiang faults, might be an erection seam or collision belt. Panxi tectonic zone still has the characteristics of continental rift valley, that is, the surface is hollow and the upper mantle is upwarping. The tectonic situation in Western Yunnan is of certain regulation with the interlacing distribution of orogenic zone and seam. The crustal thickness decreases gradually from the north to the south and the S wave velocity is globally lower here. 展开更多
关键词 receiver function INVERsION s wave velocity structure tectonic relationship
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Dinuclear Copper(Ⅱ) Complex with a New Polycarboxylate Ligand:Syntheses,Characterization and Crystal Structure 被引量:2
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作者 沈超君 盛天录 +5 位作者 傅瑞标 胡胜民 陈建珊 朱起龙 马骁 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第1期11-18,共8页
A dinuclear copper(Ⅱ) complex,[Cu2(HL)2(H2O)6] 1(H3L = 2,4,6-tri(3-carboxy-phenylthio)-1,3,5-triazine),was synthesized hydrothermally and characterized by single-crystal X-ray diffraction,IR and thermal ana... A dinuclear copper(Ⅱ) complex,[Cu2(HL)2(H2O)6] 1(H3L = 2,4,6-tri(3-carboxy-phenylthio)-1,3,5-triazine),was synthesized hydrothermally and characterized by single-crystal X-ray diffraction,IR and thermal analysis.Single-crystal X-ray diffraction reveals that complex 1 is a dinuclear copper(Ⅱ) complex,which is further extended to a 3D network by weak interactions such as O…H-O hydrogen bonds and noncovalent S...S interactions.The crystal of compound 1 belongs to monoclinic,space group C2/c,with a = 50.15(2),b = 6.789(3),c =15.667(8) ,β = 90.588(9)o,V = 5334(4) 3,Z = 4,C48H38Cu2N6O18S6,Mr = 1306.28,Dc = 1.627 g/cm3,F(000) = 2664,Rint = 0.0631,T = 293(2) K,μ = 1.112 mm-1,the final R = 0.0661 and wR = 0.1850 for 3782 observed reflections with I 2σ(I). 展开更多
关键词 COPPER crystal structure hydrogen bonds noncovalent ss interactions
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Method of reverberation ray matrix for static analysis of planar framed structures composed of anisotropic Timoshenko beam members 被引量:2
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作者 Jiao ZHANG Guohua NIE 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第2期233-242,共10页
Based on the method of reverberation ray matrix(MRRM), a reverberation matrix for planar framed structures composed of anisotropic Timoshenko(T) beam members containing completely hinged joints is developed for st... Based on the method of reverberation ray matrix(MRRM), a reverberation matrix for planar framed structures composed of anisotropic Timoshenko(T) beam members containing completely hinged joints is developed for static analysis of such structures.In the MRRM for dynamic analysis, amplitudes of arriving and departing waves for joints are chosen as unknown quantities. However, for the present case of static analysis, displacements and rotational angles at the ends of each beam member are directly considered as unknown quantities. The expressions for stiffness matrices for anisotropic beam members are developed. A corresponding reverberation matrix is derived analytically for exact and unified determination on the displacements and internal forces at both ends of each member and arbitrary cross sectional locations in the structure. Numerical examples are given and compared with the finite element method(FEM) results to validate the present model. The characteristic parameter analysis is performed to demonstrate accuracy of the present model with the T beam theory in contrast with errors in the usual model based on the Euler-Bernoulli(EB) beam theory. The resulting reverberation matrix can be used for exact calculation of anisotropic framed structures as well as for parameter analysis of geometrical and material properties of the framed structures. 展开更多
关键词 planar framed structure ANIsOtROPIC timenshenko(t beam stiffness matrix method of reverberation ray matrix(MRRM) static analysis
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Spatial distribution characteristics of bacterial community structure and gene abundance in sediments of the Bohai Sea 被引量:3
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作者 Quanrui Chen Jingfeng Fan +10 位作者 Jie Su Hongxia Ming Zhihao Sun Mengfei Li Xiaohui Zhao Yantao Wang Yingxue Zhang Huizhen Zhang Yuan Jin Xiaowan Ma Bin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第2期69-78,共10页
This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were... This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were used to assay the bacterial 16S rRNA genes in the surface sediments of 13 sampling stations in the Bohai Sea.The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury.The main phyla of bacteria recorded included Proteobacteria(52.92%),Bacteroidetes(11.76%),Planctomycetes(7.39%),Acidobacteria(6.53%)and Chloroflexi(4.97%).The genus with the highest relative abundance was Desulfobulbus(4.99%),which was the dominant genus at most sampling stations,followed by Lutimonas and Halioglobus.The main factors influencing bacterial community structure were total organic carbon,followed by depth and total phosphorus.The content of lead,cadmium,chromium,copper and zinc had a consistent effect on community structure.Arsenic showed a negative correlation with bacterial community structure in most samples,while the impact of mercury on community structure was not significant.The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes.The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants. 展开更多
关键词 Bohai sea sEDIMENts bacterial community structure HIGH-tHROUGHPUt sequencing 16s RRNA GENE
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Insights into tertiary lymphoid structures in the solid tumor microenvironment: anti-tumor mechanism, functional regulation, and immunotherapeutic strategies 被引量:3
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作者 Hua Zhao Hao Wang +1 位作者 Qiuru Zhou Xiubao Ren 《Cancer Biology & Medicine》 SCIE CAS CSCD 2021年第4期981-991,共11页
Tertiary lymphoid structures(TLSs)are ectopic immune cell aggregations that develop in peripheral tissues in response to a wide range of chronic inflammatory conditions,including infection,autoimmune disease,and cance... Tertiary lymphoid structures(TLSs)are ectopic immune cell aggregations that develop in peripheral tissues in response to a wide range of chronic inflammatory conditions,including infection,autoimmune disease,and cancer.In the tumor microenvironment(TME),the structures of TLSs,including B-cell-and T-cell-enriched areas indicate that the TLSs might be the local site during the initiation and maintenance of humoral and cellular immune responses against cancers.Numerous studies have evaluated the expression of TLSs in different cancer patients and their association with prognoses of cancer patients.It was shown that welldeveloped TLSs characterized by mature B cells synthesized tumor specific antibodies,which were considered as specific markers for a good prognosis.However,there are still some immunosuppressive factors existing in the TLSs that may affect anti-tumor responses.These factors include dysfunctional B cells,regulatory T cells,and T follicular regulatory cells.The complexity and heterogeneity of the TLS composition may affect the function and activity of TLSs;it is therefore essential to fully understand the function and influencing factors in TLSs.It has been reported that checkpoint inhibitors and vaccines are currently being developed to reprogram the TME by establishing mature TLSs to improve cancer immunotherapies.In this review,we focused on recent advances in TLSs in human solid tumors,including structural characteristics and classes,antitumor mechanisms,immunosuppressive factors,and TLSbased therapeutic approaches. 展开更多
关键词 tertiary lymphoid structure tumor microenvironment IMMUNOtHERAPY B cells t cells
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The quadratic-form identity for constructing Hamiltonian structures of the Guo hierarchy 被引量:3
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作者 董焕河 张宁 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期1919-1926,共8页
The trace identity is extended to the quadratic-form identity. The Hamiltonian structures of the multi-component Guo hierarchy, integrable coupling of Guo hierarchy and (2+l)-dimensional Guo hierarchy are obtained ... The trace identity is extended to the quadratic-form identity. The Hamiltonian structures of the multi-component Guo hierarchy, integrable coupling of Guo hierarchy and (2+l)-dimensional Guo hierarchy are obtained by the quadraticform identity. The method can be used to produce the Hamiltonian structures of the other integrable couplings or multi-component hierarchies. 展开更多
关键词 Hamiltonian structure Guo's hierarchy quadratic-form identity
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