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DABCO-catalyzed [3+4] annulations of Schiff bases with α-substituted allenes: Construction of functionalized benzazepine derivatives
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作者 Ke Wu Xiuqin Ruan +2 位作者 Shuolei Jia Enyuan Wang Qingfa Zhou 《Chinese Chemical Letters》 2025年第7期397-401,共5页
A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yiel... A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yields under mild conditions by an unprecedented mode involving β’-carbon of α-substituted allenes and the proposed mechanism is supported by capturing the intermediate.Moreover,this class of benzazepine derivatives exhibited potential ability of cytotoxicity toward cancer cells. 展开更多
关键词 DABCO Tertiary amine ALLENE BENZAZEPINE Schiff base ANNULATION Cytotoxicity
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Research and Application of Assessment of Wind Energy in Large-Scale Wind Power Bases
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作者 Ling Yuan Ling Bai +4 位作者 Jianke Li Peng Chen Haichuan Long Xia Ruan Qi Luo 《Journal of Environmental & Earth Sciences》 2025年第2期117-128,共12页
Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To thi... Improving the accuracy of the evaluation of the performance of wind farms in large wind power bases located in complex terrain under the actual atmosphere is crucial to the sustainable development of wind power.To this end,this study combined the Weather Research and Forecasting(WRF)model with the Wind Farm Parameterization(WFP)method to investigate the wake characteristics and operational performance of large onshore wind farms in the complex terrain of Jiuquan City,Gansu Province,China.The research results showed that after verification,the systematic error of the WRF simulations was less than 3%.The WRF model and the WFP scheme simulated a significant warming phenomenon within the wind power base area,while a cooling effect was observed outside.The analysis of the wake effects indicated that the impact of PhaseⅠconstruction on PhaseⅡconstruction of the wind power base was minimal.During the operation of the entire wind power base,the wind speed within the wind farm decreased by approximately 10%,and the influence range of the predominant wind direction extended over a hundred kilometers downwind.The research conclusions provide a powerful scientific basis for optimizing design and operation,improving efficiency,minimizing the negative impacts on adjacent wind turbines,and ensuring the sustainable development of wind energy through dynamic planning and scientific assessment. 展开更多
关键词 Large-Scale Wind Power base Mesoscale Simulation Risk Assessment Performance Evaluation and Improvement
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Characterizations of g-Frames and g-Riesz Bases in Hilbert Spaces 被引量:39
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作者 Yu Can ZHU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2008年第10期1727-1736,共10页
In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some nece... In this paper, we introduce the pre-frame operator Q for the g-frame in a complex Hilbert space, which will play a key role in studying g-frames and g-Riesz bases etc. Using the pre-frame operator Q, we give some necessary and sufficient conditions for a g-Bessel sequence, a g-frame, and a g-Riesz basis in a complex Hilbert space, which have properties similar to those of the Bessel sequence, frame, and Riesz basis respectively. We also obtain the relation between a g-frame and a g-Riesz basis, and the relation of bounds between a g-frame and a g-Riesz basis. Lastly, we consider the stability of a g-frame or a g-Riesz basis for a Hilbert space under perturbation. 展开更多
关键词 FRAME g-Bessel sequence G-FRAME g-riesz basis
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含Tröger’s base结构聚(苯并噁唑-酰亚胺)热重排分离膜的制备与其气体分离特性研究
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作者 宋映晓 唐傲 +3 位作者 张家霖 董杰 赵昕 张清华 《高分子学报》 北大核心 2025年第8期1358-1368,共11页
设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反... 设计合成了一种新型含Tröger’s base(TB)结构的二胺单体—2,8-二氨基-4,10-二甲基-6,12-氢-5,11-亚甲二苯并[1,5]二氮辛(TBDA),并将其与2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和2,2-双(3-氨基-4-羟基苯基)六氟丙烷(APAF)共聚反应,合成了一系列含邻羟基酰亚胺单元的聚酰亚胺(HPI).在高温下对HPI膜进行热重排处理,获得了兼具TB自聚微孔结构和热重排结构的聚(苯并噁唑-酰亚胺)气体分离膜.研究结果显示,TB自具微孔结构和热重排结构的协同作用抑制了分子链的规整堆砌,使分离膜自由体积增加,从而赋予其优异的气体分离特性.经430℃热重排反应的6FTB1-TR430膜表现出最优异的综合气体分离性能,对CO_(2)、CH_(4)、O_(2)和N_(2)的渗透系数分别为267.6、7.0、57.2和12.5 Barrer(1 Barrer=7.5×10^(−14) cm^(3)(STP)/(cm^(2)·s·Pa),STP表示标准状态,即0℃,1.01×10^(5)Pa),同时,选择性分别达到α(CO_(2)/CH_(4))=38.2及α(O_(2)/N_(2))=4.6.此外,该类分离膜的热分解温度为530~560℃,玻璃化转变温度(Tg)超过400℃,显示出优异的热稳定性.该研究为设计和开发聚酰亚胺类高效气体分离膜提供了新的思路. 展开更多
关键词 Tröger’s base结构 热重排反应 协同作用 气体分离膜
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New construction of mutually unbiased bases for odd-dimensional state space
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作者 王成红 王昆 郑驻军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期180-184,共5页
We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We ... We study the construction of mutually unbiased bases in Hilbert space for composite dimensions d which are not prime powers.We explore the results for composite dimensions which are true for prime power dimensions.We then provide a method for selecting mutually unbiased vectors from the eigenvectors of generalized Pauli matrices to construct mutually unbiased bases.In particular,we present four mutually unbiased bases in C^(15). 展开更多
关键词 mutually unbiased bases Hilbert space Pauli matrix quantum measurement
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Enhancing resistance to bacterial blight in rice using CRISPR-based base editing technology 被引量:1
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作者 Chenhao Li Bo Liu +1 位作者 Hansong Dong Bing Yang 《The Crop Journal》 2025年第1期115-124,共10页
Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is cruci... Bacterial blight(BB),caused by Xanthomonas oryzae pathovar oryzae(Xoo),poses a significant threat to rice production,particularly in Asia and West Africa.Breeding resistance against BB in elite rice varieties is crucial to advancing rice breeding program and supporting smallholder farmers.Transcription Activator-Like effectors(TALes)are key virulence factors in Xoo,with some targeting the susceptibility(S)genes such as the sugar transporter SWEET genes in rice.Among these,SWEET14 is an important S gene,with its promoter bound by the TALe TalC which exists across all sequenced African Xoo isolates.In the present study,we utilized CRISPR/Cas9-based cytidine and adenine base editors to alter the effector binding element(EBE)of TalC in the promoter of SWEET14 in rice cultivars Kitaake,IR24,and Zhonghua 11.Mutations with C to T changes in EBE led to reduced SWEET14 induction by TalC-containing Xoo strains,resulting in resistance to African Xoo isolates reliant on TalC for virulence.Conversely,A to G changes retained SWEET14 inducibility and susceptibility to Xoo in edited lines.Importantly,no off-target mutations were detected at predicted sites,and the edited lines exhibited no obvious defects in major agronomic traits in Kitaake.These results underscore the effectiveness of base editing systems for both molecular biology research and crop improvement endeavors. 展开更多
关键词 base editing base editors CBE and ABE Rice improvement Bacterial blight resistance
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Study and Practice on the Sponge City Construction Based on the Old Industrial Bases:Sponge City Construction in Xuzhou City
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作者 WANG Haiyang 《Journal of Landscape Research》 2024年第6期17-22,共6页
The old industrial base city is in the important strategic period of old industrial bases revitalization,resource-exhausted city transformation and development,and the construction of sponge city which can absorb,pene... The old industrial base city is in the important strategic period of old industrial bases revitalization,resource-exhausted city transformation and development,and the construction of sponge city which can absorb,penetrate,conserve,and purify is imperative.Based on the experimental sponge city of Xuzhou,this paper analyzes the problems of the old industrial base city.Combined with the existing work foundation,the objectives and guiding principles of Xuzhou sponge city construction are proposed.And the four ways are implemented to improve the status quo of the old industrial base,to effectively carry out the sponge city construction characterized by the old industrial bases. 展开更多
关键词 Old industrial bases XUZHOU Sponge city
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Research on the Construction and Development of Aesthetic Education Bases in Higher Education Institutions
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作者 Wei Zhou 《Journal of Contemporary Educational Research》 2024年第10期48-53,共6页
In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical... In order to implement the national aesthetic education policy,it is essential to organically integrate relevant aesthetic education resources,promote interdisciplinary education,and carry out extracurricular practical activities centered on aesthetic education.Strengthening the foundation of aesthetic education theory,addressing practical challenges in the teaching process,and closely linking research with teaching will create a feedback loop that benefits drama education.This article provides an in-depth analysis of the construction strategies,resource advantages and disadvantages,and development of aesthetic education bases,offering countermeasures and suggestions for their construction in universities.It aims to provide a solid research foundation for the growth and development of aesthetic education bases in higher education institutions. 展开更多
关键词 Aesthetic education Educational base Construction and development
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Homogenization Construction of Three-Level Teaching Bases for General Practice Medicine Under the Internet+Model
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作者 Yu Cai Ge Wu +3 位作者 Yuanyuan Jia Siqi Wang Chang Tian Yu Feng 《Journal of Contemporary Educational Research》 2024年第5期46-52,共7页
With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching l... With the continuous expansion of medical student enrollment,the number of clinical teaching bases is gradually increasing.However,there are significant differences in clinical teaching management models and teaching levels among different bases.Most clinical teaching bases have incomplete teaching management systems,inadequate teaching management institutions,insufficient teaching personnel,and inadequate implementation of teaching rules and regulations.This article combines the construction practice of three-level clinical teaching base of the General Medicine College and the First Affiliated Hospital of Xi’an Medical University.We establish a standardized management system for the three-level clinical teaching base;implement a teaching supervision system and strengthen the monitoring of teaching quality;adopt multiple evaluations to test the effectiveness of clinical teaching implementation;explore the path of homogenization construction of teaching bases in terms of unified teacher training,promoting the development of teacher teaching abilities with equal quality and excellence,and providing a reference for improving the quality of medical talent training. 展开更多
关键词 Clinical teaching base Homogenization construction General practice medicine
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Evolutionary Particle Swarm Optimization Algorithm Based on Collective Prediction for Deployment of Base Stations
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作者 Jiaying Shen Donglin Zhu +5 位作者 Yujia Liu Leyi Wang Jialing Hu Zhaolong Ouyang Changjun Zhou Taiyong Li 《Computers, Materials & Continua》 SCIE EI 2025年第1期345-369,共25页
The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(I... The wireless signals emitted by base stations serve as a vital link connecting people in today’s society and have been occupying an increasingly important role in real life.The development of the Internet of Things(IoT)relies on the support of base stations,which provide a solid foundation for achieving a more intelligent way of living.In a specific area,achieving higher signal coverage with fewer base stations has become an urgent problem.Therefore,this article focuses on the effective coverage area of base station signals and proposes a novel Evolutionary Particle Swarm Optimization(EPSO)algorithm based on collective prediction,referred to herein as ECPPSO.Introducing a new strategy called neighbor-based evolution prediction(NEP)addresses the issue of premature convergence often encountered by PSO.ECPPSO also employs a strengthening evolution(SE)strategy to enhance the algorithm’s global search capability and efficiency,ensuring enhanced robustness and a faster convergence speed when solving complex optimization problems.To better adapt to the actual communication needs of base stations,this article conducts simulation experiments by changing the number of base stations.The experimental results demonstrate thatunder the conditionof 50 ormore base stations,ECPPSOconsistently achieves the best coverage rate exceeding 95%,peaking at 99.4400%when the number of base stations reaches 80.These results validate the optimization capability of the ECPPSO algorithm,proving its feasibility and effectiveness.Further ablative experiments and comparisons with other algorithms highlight the advantages of ECPPSO. 展开更多
关键词 Particle swarm optimization effective coverage area global optimization base station deployment
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Mechanism and application prospect of magnesium-based materials in cancer treatment 被引量:1
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作者 Yutong Ma Yi Wang +7 位作者 Siwei Song Xinyue Yu Can Xu Long Wang Fan Yao Ke Yang Frank Wittee Shude Yang 《Journal of Magnesium and Alloys》 2025年第3期982-1011,共30页
Magnesium-based materials,including magnesium alloys,have emerged as a promising class of biodegradable materials with potential applications in cancer therapy due to their unique properties,including biocompatibility... Magnesium-based materials,including magnesium alloys,have emerged as a promising class of biodegradable materials with potential applications in cancer therapy due to their unique properties,including biocompatibility,biodegradability,and the ability to modulate the tumor microenvironment.The main degradation products of magnesium alloys are magnesium ions(Mg^(2+)),hydrogen(H_(2)),and magnesium hydroxide(Mg(OH)_(2)).Magnesium ions can regulate tumor growth and metastasis by mediating the inflammatory response and oxidative stress,maintaining genomic stability,and affecting the tumor microenvironment.Similarly,hydrogen can inhibit tumorigenesis through antioxidant and anti-inflammatory properties.Moreover,Mg(OH)_(2) can alter the pH of the microenvironment,impacting tumorigenesis.Biodegradable magnesium alloys serve various functions in clinical applications,including,but not limited to,bonefixation,coronary stents,and drug carriers.Nonetheless,the anti-tumor mechanism associated with magnesium-based materials has not been thoroughly investigated.This review provides a comprehensive overview of the current state of magnesium-based therapies for cancer.It highlights the mechanisms of action,identifies the challenges that must be addressed,and discusses prospects for oncological applications. 展开更多
关键词 Cancer therapy Magnesium based materials Magnesium ions Hydrogen gas Mg(OH)_(2) Anti-tumor mechanism
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Design,synthesis,and detection of Al^(3+)of two zinc complexes based on Schiff base ligands
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作者 YANG Yuanyu XUE Jianhua +3 位作者 BAI Yujia CUI Lulu YANG Dongdong MA Qi 《无机化学学报》 北大核心 2025年第6期1207-1216,共10页
Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-... Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-4-methoxybenzaldehyde and 2-hydroxy-3-methoxybenzaldehyde ligands,respectively,where H_(2)L1=5-methoxy-2-(phthalazin-1-ylhydrazonomethyl)-phenol,H_(2)L2=2-methoxy-6-(phthalazin-1-yl-hydrazonomethyl)-phenol,HL3=2-(1,8-dihydro-[1,2,4]triazolo[3,4-α]phthalazin-3-yl)-6-methoxy-phenol.Complexes 1 and 2 were characterized by infrared spectroscopy,elemental analysis,single-crystal X-ray diffraction,powder X-ray diffraction,etc.It is worth noting that the cinnolin-3-yl-hydrazine ligand and 2-hydroxy-3-methoxybenzaldehyde form two types of Schiff bases(H_(2)L2 and HL3)when in situ reacting and coordinating with Zn(Ⅱ),and HL3 also has two coordination modes.In addition,the fluorescence performance showed that complex 1 can achieve selective and sensitive sensing of Al^(3+)in water with a detection limit of 6.37μmol·L^(-1).CCDC:2413978,1;2413979,2. 展开更多
关键词 Zn-complex Schiff base FLUORESCENCE Al^(3+)detection
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孟德尔随机化MR-Base数据库的应用 被引量:1
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作者 蒿花 陈新欢 +3 位作者 姜红 耿辉 马茂 米白冰 《中国循证心血管医学杂志》 2025年第3期270-273,共4页
越来越多的流行病学证据表明,生活方式、饮食习惯等环境因素与多种健康状况之间存在复杂的因果关系。然而,传统的观察性研究易受到混杂因素的影响,无法准确揭示疾病与环境间的因果关系。孟德尔随机化研究(Mendelian Randomization,MR)... 越来越多的流行病学证据表明,生活方式、饮食习惯等环境因素与多种健康状况之间存在复杂的因果关系。然而,传统的观察性研究易受到混杂因素的影响,无法准确揭示疾病与环境间的因果关系。孟德尔随机化研究(Mendelian Randomization,MR)通过遗传变异的随机分配可有效减少混杂因素偏倚,从而更可靠地估计因果效应。MR-Base数据库作为全球最大的孟德尔随机化研究平台,汇集了来自世界各地的遗传数据,为研究者提供了探索遗传变异与健康结局之间因果关系的宝贵资源。本文探讨孟德尔随机化在MR-Base数据库中的应用,旨在介绍该方法的基本原理、数据库的结构与功能,以及如何利用这些数据来探索环境因素与包括心血管疾病、代谢性疾病和精神健康研究等在内的健康结局潜在关联。同时,本文展望了孟德尔随机化方法的未来发展方向,强调了其在精准医疗和公共卫生政策中的潜在作用。 展开更多
关键词 MR-base数据库 孟德尔随机化 遗传变异 工具变量
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Crystal structure and antibacterial activity of two Gd_(2)complexes based on polydentate Schiff-base ligands
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作者 ZHANG Yingyue KANG Liuqing +2 位作者 YANG Yating GUAN Xiaofen WANG Wenmin 《无机化学学报》 北大核心 2025年第9期1867-1877,共11页
Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene... Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2. 展开更多
关键词 Gd_(2)complex polydentate Schiff base crystal structure DNA INTERACTION antibacterial activity
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Impact of Information and Communication Technologies Based Initiatives: An Attitudinal Change in Students and Teachers
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作者 Surya Narayan Gupta Manohar Sah Akhilesh Chaube 《Applied Mathematics》 2025年第2期190-199,共10页
There is curiosity and awareness throughout the world regarding the role of Information and Communication technologies. This is felt in each and every section of society. Several studies have confirmed and considered ... There is curiosity and awareness throughout the world regarding the role of Information and Communication technologies. This is felt in each and every section of society. Several studies have confirmed and considered information and communication technology’s significance in the field of education. It has not only affected learners but also to the teachers. This paper explores how ICT-based projects affect teachers’ and students’ attitudes. The data was collected through self-prepared attitude scale. It was distributed among the teachers and students of various schools. Two hundred students and one hundred twenty teachers responded to the questionnaire. Analysis was done through the data collected from the teachers as well as from students. The study’s conclusions demonstrated that while there was no significant variation in the attitudes of teachers utilizing different ICT-based programs, there was a substantial difference in the students’ attitude toward learning with different ICT-based programs. 展开更多
关键词 ICT based Initiatives ICT Teacher’s Attitude Student’s Attitude
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Call forpapers SI: Target-based drug screening
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《Journal of Pharmaceutical Analysis》 2025年第1期F0004-F0004,共1页
Target-based and phenotype-based methods are the two main approaches for drug screening.Target-based drug screening focuses on specific targets CPA highly correlated with disease mechanisms,by detecting protein-ligand... Target-based and phenotype-based methods are the two main approaches for drug screening.Target-based drug screening focuses on specific targets CPA highly correlated with disease mechanisms,by detecting protein-ligand binding structure,dynamics and affinity.Currently,the four mainstream drug targets are G protein-coupled receptors(GPCRs),kinases,ion channels,and nuclear receptors,accounting for over 70%of effective drug targets,most of which are membrane proteins and enzymes.In recent years,various new drug targets have been continuously discovered,and the research focus has shifted from simple affinity analysis to high-throughput and high-content screening,as well as exploring drug-target interaction modes.These deepen reliance on the analytical techniques to have higher sensitivity,recognition specificity,and applicability to diversified target structures,which promoting the rapid development of novel screening methods. 展开更多
关键词 nuclear receptorsaccounting target based drug screening phenotype based methods membrane proteins drug screening drug targets protein ligand binding drug screeningtarget based
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RUNX2 is essential for maintaining synchondrosis chondrocytes and cranial base growth
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作者 Shawn A.Hallett Ashley Dixon +9 位作者 Isabella Marrale Lena Batoon JoséBrenes Annabelle Zhou Ariel Arbiv Vesa Kaartinen Benjamin Allen Wanida Ono Renny T.Franceschi Noriaki Ono 《Bone Research》 2025年第4期939-956,共18页
The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with ... The cranial base synchondroses,comprised of opposite-facing bidirectional chondrocyte layers,drive anteroposterior cranial base growth.In humans,RUNX2 haploinsufficiency causes cleidocranial dysplasia associated with deficient midfacial growth.However,how RUNX2 regulates chondrocytes in the cranial base synchondroses remains unknown.To address this,we inactivated Runx2 in postnatal synchondrosis chondrocytes using a tamoxifen-inducible Fgfr3-creER(Fgfr3-Runx2cKO)mouse model.Fgfr3-Runx2cKO mice displayed skeletal dwarfism and reduced anteroposterior cranial base growth associated with premature synchondrosis ossification due to impaired chondrocyte proliferation,accelerated hypertrophy,apoptosis,and osteoclast-mediated cartilage resorption.Lineage tracing reveals that Runx2-deficient Fgfr3+cells failed to differentiate into osteoblasts.Notably,Runx2-deficient chondrocytes showed an elevated level of FGFR3 and its downstream signaling components,pERK1/2 and SOX9,suggesting that RUNX2 downregulates FGFR3 in the synchondrosis.This study unveils a new role of Runx2 in cranial base chondrocytes,identifying a possible RUNX2-FGFR3-MAPK-SOX9 signaling axis that may control cranial base growth. 展开更多
关键词 cranial base synchondroses chondrocyte proliferation HYPERTROPHY cleidocranial dysplasia cranial base synchondrosescomprised apoptosis inactivated runx RUNX
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A rhombic Dy_(4)-based complex showing remarkable single-molecule magnet behavior
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作者 HOU Yinling JI Jia +5 位作者 YU Hong BIAN Xiaoyun GUAN Xiaofen QIU Jing REN Shuyi FANG Ming 《无机化学学报》 北大核心 2025年第3期605-612,共8页
A tetranuclear Ln(Ⅲ)-based complex:[Dy_(4)(dbm)_(4)(L)_(6)(μ_(3)-OH)_(2)]·CH_(3)CN(1)(HL=5-[(4-methylbenzylidene)amino]quinolin-8-ol,Hdbm=dibenzoylmethane)was manufactured and its structure was characterized in... A tetranuclear Ln(Ⅲ)-based complex:[Dy_(4)(dbm)_(4)(L)_(6)(μ_(3)-OH)_(2)]·CH_(3)CN(1)(HL=5-[(4-methylbenzylidene)amino]quinolin-8-ol,Hdbm=dibenzoylmethane)was manufactured and its structure was characterized in detail.Xray diffraction analysis shows that complex 1 belongs to the monoclinic crystal system and its space group is P2_1/n,which contains a rhombic Dy_(4)core.Magnetic measurements of 1 suggest it possesses extraordinary single-molecule magnet(SMM)behavior.Its energy barrier U_(eff)/k_(B)was 116.7 K,and the pre-exponential coefficient τ_(0)=1.05×10~(-8)s.CCDC:2359322. 展开更多
关键词 tetranuclear Dy(Ⅲ)complex Schiff base ligand crystal structure magnetic property single⁃molecule magnet
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Biochars improve agricultural production:The evidence base is limited
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作者 Vincent CHAPLOT Philippe BAVEYE +3 位作者 RenéGUENON Elie LE GUYADER Budiman MINASNY Anoop Kumar SRIVASTAVA 《Pedosphere》 2025年第1期295-298,共4页
Biochar application to soil is commonly recognized to improve soil fertility and consequently biomass and food production sustainably.We re-examined the robustness of the underlying data and found that,of the 12000+ p... Biochar application to soil is commonly recognized to improve soil fertility and consequently biomass and food production sustainably.We re-examined the robustness of the underlying data and found that,of the 12000+ publications on“biochar and agriculture”used in meta-studies,only 109 Institute for Scientific Information(ISI)papers(or 0.9%)provide experimental data on the impacts on crop yield and/or biomass production. 展开更多
关键词 SOIL IMPROVE base
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A Dynamic Knowledge Base Updating Mechanism-Based Retrieval-Augmented Generation Framework for Intelligent Question-and-Answer Systems
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作者 Yu Li 《Journal of Computer and Communications》 2025年第1期41-58,共18页
In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilizati... In the context of power generation companies, vast amounts of specialized data and expert knowledge have been accumulated. However, challenges such as data silos and fragmented knowledge hinder the effective utilization of this information. This study proposes a novel framework for intelligent Question-and-Answer (Q&A) systems based on Retrieval-Augmented Generation (RAG) to address these issues. The system efficiently acquires domain-specific knowledge by leveraging external databases, including Relational Databases (RDBs) and graph databases, without additional fine-tuning for Large Language Models (LLMs). Crucially, the framework integrates a Dynamic Knowledge Base Updating Mechanism (DKBUM) and a Weighted Context-Aware Similarity (WCAS) method to enhance retrieval accuracy and mitigate inherent limitations of LLMs, such as hallucinations and lack of specialization. Additionally, the proposed DKBUM dynamically adjusts knowledge weights within the database, ensuring that the most recent and relevant information is utilized, while WCAS refines the alignment between queries and knowledge items by enhanced context understanding. Experimental validation demonstrates that the system can generate timely, accurate, and context-sensitive responses, making it a robust solution for managing complex business logic in specialized industries. 展开更多
关键词 Retrieval-Augmented Generation Question-and-Answer Large Language Models Dynamic Knowledge base Updating Mechanism Weighted Context-Aware Similarity
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