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Adaptable and Dynamic Access Control Decision-Enforcement Approach Based on Multilayer Hybrid Deep Learning Techniques in BYOD Environment
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作者 Aljuaid Turkea Ayedh M Ainuddin Wahid Abdul Wahab Mohd Yamani Idna Idris 《Computers, Materials & Continua》 SCIE EI 2024年第9期4663-4686,共24页
Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control sy... Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control systems,such as Attribute-Based Access Control(ABAC)and Role-Based Access Control(RBAC),are limited in their ability to enforce access decisions due to the variability and dynamism of attributes related to users and resources.This paper proposes a method for enforcing access decisions that is adaptable and dynamic,based on multilayer hybrid deep learning techniques,particularly the Tabular Deep Neural Network Tabular DNN method.This technique transforms all input attributes in an access request into a binary classification(allow or deny)using multiple layers,ensuring accurate and efficient access decision-making.The proposed solution was evaluated using the Kaggle Amazon access control policy dataset and demonstrated its effectiveness by achieving a 94%accuracy rate.Additionally,the proposed solution enhances the implementation of access decisions based on a variety of resource and user attributes while ensuring privacy through indirect communication with the Policy Administration Point(PAP).This solution significantly improves the flexibility of access control systems,making themmore dynamic and adaptable to the evolving needs ofmodern organizations.Furthermore,it offers a scalable approach to manage the complexities associated with the BYOD environment,providing a robust framework for secure and efficient access management. 展开更多
关键词 BYOD security access control access control decision-enforcement deep learning neural network techniques TabularDNN MULTILAYER dynamic adaptable FLEXIBILITY bottlenecks performance policy conflict
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ACORDE Project:Adaptable Residential Buildings for a New Social Framework
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作者 Pablo Emilio Branchi 《Journal of Civil Engineering and Architecture》 2024年第3期118-133,共16页
ACORDE project seeks to maximize buildings´flexibility,conceiving a residential building made of legally independent functional units that can be connected to or disconnected from each other with easy,plug-in fac... ACORDE project seeks to maximize buildings´flexibility,conceiving a residential building made of legally independent functional units that can be connected to or disconnected from each other with easy,plug-in facilities,in a way that permits to purchase exactly what the user need,as well as allows future changes for buildings to be adapted to the needs of their occupants,the user decides how to best utilize the space by acquiring or separating functional units along the years.For this to be possible,in addition to the legally independent modules concept,a diaphanous and very well organized structure is projected as well as a very solid and efficient envelope to ensure durability and minimal maintenance.The efficient occupancy of space leads to an optimal use of energy. 展开更多
关键词 ADAPTABILITY FLEXIBILITY demographic changes end-uses plug&play
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Adaptable Processing: Stage Development
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作者 Dumitru Todoroi 《Journal of Literature and Art Studies》 2013年第5期305-311,共7页
The development and evolution of Microsoft Office and Microsoft Windows shells are based in general on the special methodology of software creation and implementation such as macros, subroutine, custom commands, and s... The development and evolution of Microsoft Office and Microsoft Windows shells are based in general on the special methodology of software creation and implementation such as macros, subroutine, custom commands, and specialized features. Microsoft Office for Mac has for long been criticized for its lack of support of Unicode and BiDi languages, notably Arabic and Hebrew. This has not changed in the Office 2008 version. Microsoft Office 2010 (also called Office 2010 and Office 14) is the current version of the Microsoft Office productivity suite for Microsoft Windows, and the successor to Microsoft Office 2007. With Office 2010, users are in control, getting things done and producing amazing results however and wherever they work best. Ms Office 2010 is the last version of Microsoft Office with support for Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008 due to Office 2013 requiring Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, or Windows RT. Adaptive hardware (Ugurdag, 2006) reflects the capability of a system to maintain or improve its performance in the context of internal or external changes. Adaptation at hardware levels increases the system capabilities beyond what is possible with software-only solutions. Algorithms, techniques, and their implementation in hardware are developed over a diverse variety of applications. The methodology of the On-Off-Line adaptable processors (Todoroi & Micusha, 2012) support development of adaptable software and hardware. Automatic creation of the Off-Line adaptable processors are proved. Development of the On-Line and On-Off-Line adaptable processors based on Off-Line processing creation method is proposed (Todoroi, Micu^a, & Todoroi, 2009; Todoroi, 2008a, 2008b) 展开更多
关键词 ADAPTABILITY ADAPTIVE PROCESSOR LANGUAGE adaptable processor adaptive hardware adaptable software
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ADAPTABLE DESIGN OF MACHINE TOOLS STRUCTURES 被引量:10
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作者 XU Yanshen CHEN Yongliang +1 位作者 ZHANG Guojun GU Peihua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期7-15,共9页
Adaptable design aims to extend the utilities of design and product. The specific methods are developed for practical applications of adaptable design in the design of mechanical structures, including adaptable platfo... Adaptable design aims to extend the utilities of design and product. The specific methods are developed for practical applications of adaptable design in the design of mechanical structures, including adaptable platform, interface and module designs. Adaptable redesign problems are formulated as adaptable platform design under adaptability bound constraints. Analysis tools are then suggested for the implementation of the redesign of machine tool structures, including variation techniques based sensitivity analysis, similarity-based commonality analysis, performance improvement, and adaptability measures. The specific measure of adaptability for machine tool structures is measured through the quantification of the structural similarity and performance improvement gained from adaptable design. The method provides designers with an approach that brings adaptability into the design process, with considering the cost and benefits of such adaptability. The redesign of CNC spiral bevel gear cutting machine structures has been included to illustrate these concepts and methods. 展开更多
关键词 adaptable design Machine tools
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Reshapeable,rehealable and recyclable sensor fabricated by direct ink writing of conductive composites based on covalent adaptable network polymers 被引量:2
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作者 Xu He Yuchen Lin +6 位作者 Yuchen Ding Arif M Abdullah Zepeng Lei Yubo Han Xiaojuan Shi Wei Zhang Kai Yu 《International Journal of Extreme Manufacturing》 SCIE EI 2022年第1期94-107,共14页
Covalent adaptable network(CAN)polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable,rehealable,and fully recyclable electronics.On the other hand,3D printing as a deterministic man... Covalent adaptable network(CAN)polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable,rehealable,and fully recyclable electronics.On the other hand,3D printing as a deterministic manufacturing method has a significant potential to fabricate electronics with low cost and high design freedom.In this paper,we incorporate a conductive composite consisting of polyimine CAN and multi-wall carbon nanotubes into direct-ink-writing 3D printing to create polymeric sensors with outstanding reshaping,repairing,and recycling capabilities.The developed printable ink exhibits good printability,conductivity,and recyclability.The conductivity of printed polyimine composites is investigated at different temperatures and deformation strain levels.Their shape-reforming and Joule heating-induced interfacial welding effects are demonstrated and characterized.Finally,a temperature sensor is 3D printed with defined patterns of conductive pathways,which can be easily mounted onto 3D surfaces,repaired after damage,and recycled using solvents.The sensing capability of printed sensors is maintained after the repairing and recycling.Overall,the 3D printed reshapeable,rehealable,and recyclable sensors possess complex geometry and extend service life,which assist in the development of polymer-based electronics toward broad and sustainable applications. 展开更多
关键词 bond exchange reactions polyimine covalent adaptable networks direct ink writing rehealable electronics RECYCLABILITY
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A Binary Images Watermarking Algorithm Based on Adaptable Matrix 被引量:1
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作者 ZHANG Fan ZHANG Junliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期595-599,共5页
A watermarking algorithm of binary images using adaptable matrix is presented. An adaptable matrix is designed to evaluate the smoothness and the connectivity of binary images. The watermark is embedded according to t... A watermarking algorithm of binary images using adaptable matrix is presented. An adaptable matrix is designed to evaluate the smoothness and the connectivity of binary images. The watermark is embedded according to the adaptable matrix in this algorithm. In the proposed watermarking algorithm, each image block implements a XOR operation with the binary adaptable matrix, which has the same size with the image block, and in order to embed the watermark data, a multiplication operation are also implemented with the weight matrix. The experimental results show that proposed scheme has a good performance. 展开更多
关键词 WATERMARKING binary image adaptable matrix
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ADAPTABLE DESIGN IN PRODUCT DEVELOPMENT 被引量:2
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作者 WU Qingming MEI Huafeng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第3期348-351,共4页
A newly emerging design pattern, named as adaptable design (AD), which aims at developing products that are adaptable from design to post-life cycle, is discussed. AD consists of four main phases: product modeling,... A newly emerging design pattern, named as adaptable design (AD), which aims at developing products that are adaptable from design to post-life cycle, is discussed. AD consists of four main phases: product modeling, design platform, specific design and product redesign. A new process-based design data model (PDDM) is presented which is organized according to the principles of convenient knowledge extraction, data representation, layout, sharing and reuse. Based on the PDDM, a universal design platform for product family development is established, which has characters of modularity, parameter-driven, variant design, etc. The framework of the platform is also proposed as a conceptual structure and overall logical organization for generating a family of products. AD methodology is successfully applied to develop a family of tunnel boring machine (TBM) for different engineering projects, with the efficiency of our developing team being greatly increased. 展开更多
关键词 adaptable design Product development Process-based design data model(PDDM) Design platform
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Quantitatively probing interactions between membrane with adaptable wettability and oil phase in oil/water separation
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作者 Zhong-Zheng Xu Ming-Wei Zhao +6 位作者 Yi-Ning Wu Jia-Wei Liu Ning Sun Zi-Zhao Wang Yi-Ming Zhang Lin Li Cai-Li Dai 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2564-2574,共11页
The membrane method based on adaptive wettability shows great advantages in oil-water separation.At present,researches focus on the excellent application performance of the membrane material,while the quantitative ana... The membrane method based on adaptive wettability shows great advantages in oil-water separation.At present,researches focus on the excellent application performance of the membrane material,while the quantitative analysis of interactions in oil-water separation is rarely recognized.Herein,we constructed an adaptable wettability membrane with multiple polymer networks by polydopamine(PDA)and mussel-inspired amphiphilic polymer.Based on the Owens three-probe liquid method,the surface energy of the modified membrane was verified to meet the adaptive wettability conditions,with surface energies(γ-8)of 147.6 mJ m^(−2)(superhydrophilic/underwater superoleophobic)and 49.87 mJ m^(−2)(superhydrophobic/superoleophobic),respectively.The adhesion or repulsion of the membrane to the oil phase under different conditions during the separation process was quantified by the chemical probe AFM technique.In addition,the oil-water selective separation mechanism was further analyzed in a simplified membrane microchannel model.The results show that the different wetting produces capillary additional pressure in opposite directions,resulting in different energies to be overcome when the oil or water passes through the microchannels,thus achieving selective separation. 展开更多
关键词 adaptable wettability Selective oil/water separation Interface interaction Probe AFM technique
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Taking Diplomatic Strategy Adaptable to Environment
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作者 Ye Zicheng Ye Zicheng is Dean and Professor at the Department of Diplomatic Relations at the Institute of International Relations, Beijing University. 《Contemporary International Relations》 2003年第1期33-37,共5页
Looking from China’s neighboring environment, the America factor is undoubtedly the most important factor in analyzing China’s neighboring security. Speaking of U. S. influence on China’s neighboring security, some... Looking from China’s neighboring environment, the America factor is undoubtedly the most important factor in analyzing China’s neighboring security. Speaking of U. S. influence on China’s neighboring security, some scholars tend to believe that the unfavorable factors play a dominant role. This conclusion comes from the "new moonshape encirclement" already existing since the Cold War in America, 展开更多
关键词 that DE MORE IT with HAVE in of Taking Diplomatic Strategy adaptable to Environment
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Towards Wide-Open, Adaptable DCF Implementation for Dynamic Networks 被引量:2
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作者 Wang Shan Abdelhakim Hafid +3 位作者 Zhao Haitao Huang Shengchun Xieng Chunlin Wei Jibo 《China Communications》 SCIE CSCD 2012年第7期77-89,共13页
Abstract: This work proposes a Field Programmable Gate Array (FPGA)-oriented architecture for the IEEE 802.11 Distributed Coordination Function (DCF) transceiver. We describe the functional blocks carrying out th... Abstract: This work proposes a Field Programmable Gate Array (FPGA)-oriented architecture for the IEEE 802.11 Distributed Coordination Function (DCF) transceiver. We describe the functional blocks carrying out the Carrier Sense Multiple Accesses with Collision Avoidance (CSMA/CA), develop the interfaces to the application layer and the physical layer, and implement it on FPGA devices by utilizing Very-high-speed-integrated-circuit Hardware Description Language (VHDL). 展开更多
关键词 wireless networks DCF adaptation capability FPGA CSM A/CA cognitive networks
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A SPEAKER ADAPTABLE VERY LOW BIT RATE SPEECH CODER BASED ON HMM
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作者 彭煳 朱杰 《Journal of Shanghai Jiaotong university(Science)》 EI 2000年第2期1-5,共5页
This paper presented a speaker adaptable very low bit rate speech coder based on HMM (Hidden Markov Model) which includes the dynamic features, i.e., delta and delta delta parameters of speech. The performance of this... This paper presented a speaker adaptable very low bit rate speech coder based on HMM (Hidden Markov Model) which includes the dynamic features, i.e., delta and delta delta parameters of speech. The performance of this speech coder has been improved by using the dynamic features generated by an algorithm for speech parameter generation from HMM because the generated speech parameter vectors reflect not only the means of static and dynamic feature vectors but also the covariance of those. The encoder part is equivalent to an HMM based phoneme recognizer and transmits phoneme indexes, state durations, pitch information and speaker characteristics adaptation vectors to the decoder. The decoder receives those messages and concatenates phoneme HMM sequence according to the phoneme indexes. Then the decoder generates a sequence of mel cepstral coefficient vectors using HMM based speech parameter generation technique. Finally the decoder synthesizes speech by directly exciting the MLSA(Mel Log Spectrum Approximation) filter with the generated mel cepstral coefficient vectors, according to the pitch information. 展开更多
关键词 mel cepstral COEFFICIENTS hidden MARKOV model MLSA filter SPEAKER ADAPTATION Document code:A
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Advancing neural regeneration via adaptable hydrogels:Enriched with Mg^(2+)and silk fibroin to facilitate endogenous cell infiltration and macrophage polarization 被引量:3
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作者 Yisheng Gao Yingyu Wang +8 位作者 Jianye Zhang Miao Zhang Chaolun Dai Yang Zhang Luzhong Zhang Liming Bian Yumin Yang Kunyu Zhang Yahong Zhao 《Bioactive Materials》 SCIE CSCD 2024年第3期100-113,共14页
Peripheral nerve injury is a complex and challenging medical condition due to the limited ability of nerves to regenerate, resulting in the loss of both sensory and motor function. Hydrogels have emerged as a promisin... Peripheral nerve injury is a complex and challenging medical condition due to the limited ability of nerves to regenerate, resulting in the loss of both sensory and motor function. Hydrogels have emerged as a promising biomaterial for promoting peripheral nerve regeneration, while conventional hydrogels are generally unable to support endogenous cell infiltration due to limited network dynamics, thereby compromising the therapeutic outcomes. Herein, we present a cell adaptable hydrogel containing a tissue-mimetic silk fibroin network and a dynamically crosslinked bisphosphonated-alginate network. The dynamic network of this hydrogel can respond to cell-generated forces to undergo the cell-mediated reorganization, thereby effectively facilitating the rapid infiltration of Schwann cells and macrophages, as well as the ingrowth of axons. We further show that the magnesium ions released from the hydrogel not only promote neurite outgrowth but also regulate the polarization of macrophages in a sequential manner, contributing to the formation of a regenerative microenvironment. Therefore, this hydrogel effectively prevents muscle atrophy and promotes the regeneration and functional recovery of nerve defects of up to 10 mm within 8 weeks. The findings from this study demonstrate that adaptable hydrogels are promising inductive biomaterials for enhancing the therapeutic outcomes of peripheral nerve injury treatments. 展开更多
关键词 adaptable hydrogels MAGNESIUM Cell infiltration Regenerative microenvironment Peripheral nerve repair
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Synergistic Dual Dynamic Bonds in Covalent Adaptable Networks 被引量:2
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作者 Jun Zhao Zhaoming Zhang +1 位作者 Chunyu Wang Xuzhou Yan 《CCS Chemistry》 CSCD 2024年第1期41-56,共16页
Covalent adaptable networks(CANs),comprising polymer networks crosslinked by dynamic covalent bonds(DCBs),have garnered considerable attention as sustainable materials.Mastering the stress relaxation of CANs is essent... Covalent adaptable networks(CANs),comprising polymer networks crosslinked by dynamic covalent bonds(DCBs),have garnered considerable attention as sustainable materials.Mastering the stress relaxation of CANs is essential for controlling their viscoelastic properties.An unexpected acceleration of stress relaxation has been observed in CANs containing dual dynamic bonds.The dynamic behavior of the second dynamic bonds can accelerate stress relaxation and lower the relaxation activation energy of dual dynamic CANs compared to analogous CANs that rely on only one type of DCB.These findings complement current approaches that utilize catalysts or adjust network parameters.In this minireview,we summarize the synergistic acceleration effects in various CANs containing dual dynamic bonds.We classify these effects based on the second dynamic bonds,including noncovalent bonds,mechanical bonds,and the second DCBs.We also discuss the mechanisms behind this synergy.Finally,we highlight the challenges and offer perspectives on harnessing the synergistic effects of these dual dynamic systems to expand the chemistry and applications of CANs. 展开更多
关键词 covalent adaptable networks dynamic covalent bonds dynamic materials stress relaxation synergistic effect
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Designing Tough,Printable,and Adaptable Eutectogels with Multinetworks via Synergy of Rapid Orthogonal Photopolymerizations and Solvent Effect in Seconds 被引量:1
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作者 Jupen Liu Lijun Zhou +3 位作者 Ping Zhang Yanxia Zhao Hongqiu Wei You Yu 《CCS Chemistry》 CSCD 2024年第2期390-402,共13页
Achieving a straightforward design of tough,printable,and adaptable polymeric eutectogels is still challenging in related fields due to the uncontrollable polymerization and solvent-exchanging processes,and inherent c... Achieving a straightforward design of tough,printable,and adaptable polymeric eutectogels is still challenging in related fields due to the uncontrollable polymerization and solvent-exchanging processes,and inherent contrasting multiple networks.Here,we report a one-step synergistic strategy based on ruthenium chemistry-catalyzed photopolymerization and solvent effect for preparing high-performance eutectogels.This orthogonal ruthenium photochemistry helps multinetworks formation via phenol-coupling of gelatin and copolymerization of acrylamide(AAm)and[2-(methacryloyloxy)ethyl]trimethylammonium tetrafluoroborate(META)monomers in seconds.The obvious difference in the supramolecular interactions of free AAm monomers and polymerized units in P(AAm-co-META)with deep eutectic solvents(DESs)significantly promotes the microphase-separation behavior in eutectogels.Consequently,the in situ polymerization and microphase-separation behavior enable the as-prepared eutectogel materials to have excellent mechanical properties(stress of∼1.2 MPa),toughness(∼4.0 MJ m^(−3)),elasticity,adaptivity,and conductivity(∼0.5 S m^(−1)at room temperature).Also,the critical strength of the resultant eutectogels can be modulated by varying the DES constituents.This rapid and well-controlled synergistic approach is compatible with extrusion printing techniques to make flexible sensors with high sensitivities and response times to detect pressure in a range of 0–500 kPa.Such a general and simple strategy has application potential in biological,engineering,and material sciences. 展开更多
关键词 orthogonal chemistry visible-light photopolymerization solvent effect microphase separation adaptable polymers printable eutectogels
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Creep-Resistant Covalent Adaptable Networks with Excellent SelfHealing and Reprocessing Performance via Phase-Locked Dynamic Covalent Benzopyrazole-Urea Bonds
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作者 Miao Xie Xiao-Rong Wang +1 位作者 Zhan-Hua Wang He-Sheng Xia 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第10期1545-1556,I0013,共13页
Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to... Covalent adaptive networks(CANs)are capable of undergoing segment rearrangement after being heated,which endows the materials with excellent self-healing and reprocessing performance,providing an efficient solution to the environment pollution caused by the plastic wastes.The main challenge remains in developing CANs with both excellent reprocessing performance and creep-resistance property.In this study,a series of CANs containing dynamic covalent benzopyrazole-urea bonds were developed based on the addition reaction between benzopyrazole and isocyanate groups.DFT calculation confirmed that relatively low dissociation energy is obtained through undergoing a five-member ring transition state,confirming excellent dynamic property of the benzopyrazole-urea bonds.As verified by the FTIR results,this nice dynamic property can be well maintained after incorporating the benzopyrazole-urea bonds into polymer networks.Excellent self-healing and reprocessing performance is observed by the 3-ABP/PDMS elastomers owing to the dynamic benzopyrazole-urea bonds.Phase separation induced by the aggregation of the hard segments locked the benzopyrazole-urea bonds,which also makes the elastomers display excellent creep-resistance performance.This hard phase locking strategy provides an efficient approach to design CANs materials with both excellent reprocessing and creep-resistance performance. 展开更多
关键词 Covalent adaptive networks Self-healing polymer Dynamic covalent bond
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Adaptable hydrogel with reversible linkages for regenerative medicine:Dynamic mechanical microenvironment for cells 被引量:16
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作者 Zongrui Tong Lulu Jin +4 位作者 Joaquim Miguel Oliveira Rui LReis Qi Zhong Zhengwei Mao Changyou Gao 《Bioactive Materials》 SCIE 2021年第5期1375-1387,共13页
Hydrogels are three-dimensional platforms that serve as substitutes for native extracellular matrix.These materials are starting to play important roles in regenerative medicine because of their similarities to native... Hydrogels are three-dimensional platforms that serve as substitutes for native extracellular matrix.These materials are starting to play important roles in regenerative medicine because of their similarities to native matrix in water content and flexibility.It would be very advantagoues for researchers to be able to regulate cell behavior and fate with specific hydrogels that have tunable mechanical properties as biophysical cues.Recent developments in dynamic chemistry have yielded designs of adaptable hydrogels that mimic dynamic nature of extracellular matrix.The current review provides a comprehensive overview for adaptable hydrogel in regenerative medicine as follows.First,we outline strategies to design adaptable hydrogel network with reversible linkages according to previous findings in supramolecular chemistry and dynamic covalent chemistry.Next,we describe the mechanism of dynamic mechanical microenvironment influence cell behaviors and fate,including how stress relaxation influences on cell behavior and how mechanosignals regulate matrix remodeling.Finally,we highlight techniques such as bioprinting which utilize adaptable hydrogel in regenerative medicine.We conclude by discussing the limitations and challenges for adaptable hydrogel,and we present perspectives for future studies. 展开更多
关键词 adaptable hydrogel Dynamic mechanical microenvironment Supramolecular chemistry Dynamic covalent chemistry Yes-associated protein
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Recent advances in recyclable thermosets and thermoset composites based on covalent adaptable networks 被引量:3
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作者 Yihe Zhang Li Zhang +6 位作者 Guotao Yang Yalin Yao Xu Wei Tianchi Pan Juntao Wu Moufeng Tian Penggang Yin 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第33期75-87,共13页
Recyclable thermosets and thermoset composites with covalent adaptable networks(CANs,or dynamic covalent networks) have attracted considerable attention in recent years due to the combined merits of excellent mechanic... Recyclable thermosets and thermoset composites with covalent adaptable networks(CANs,or dynamic covalent networks) have attracted considerable attention in recent years due to the combined merits of excellent mechanical and thermal properties,and chemical stabilities of traditional thermosets and recyclable,remoldable,and reprocessable attributes of thermoplastics.In this paper,we present an overview of the current strategies for synthesizing recyclable thermosets based on CANs,which involve recyclability,reprocessability,and possible rehealability.The recent literature examples are categorized based on the underlying controlled-cleavable linkages such as transesterification,DA/retro-DA chemistry,imine bonds,disulfide metathesis,dynamic B-O bonds,hemiaminals/hexahydrotriazines,and acetal linkages.Various degradation and malleability methods and resulting mechanical properties of the recycled thermosets and thermoset composites are presented.The emerging applications of recyclable thermosets and thermoset composites,with emphasis on their usage in adhesives,biomedical materials,wearable devices,coatings,and 3D printing materials,are also illustrated.Finally,a perspective on the challenges and future perspectives is briefly summarized. 展开更多
关键词 Covalent adaptable networks(CANs) RECYCLABLE CROSSLINK Degradation Property
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Cooperative Chemical Coupling and Physical Lubrication Effects Construct Highly Dynamic Ionic Covalent Adaptable Network for High-Performance Wearable Electronics 被引量:2
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作者 Lijie Sun Hongfei Huang +6 位作者 Qingbao Guan Lei Yang Luzhi Zhang Benhui Hu Rasoul Esmaeely Neisiany Zhengwei You Meifang Zhu 《CCS Chemistry》 CSCD 2023年第5期1096-1107,共12页
Covalent adaptable networks(CANs),which combine the benefits of traditional thermosets and thermoplastics,have attracted considerable attention.The dynamics of reversible covalent bonds and mobility of polymer chains ... Covalent adaptable networks(CANs),which combine the benefits of traditional thermosets and thermoplastics,have attracted considerable attention.The dynamics of reversible covalent bonds and mobility of polymer chains in CANs determine the topological rearrangement of the polymeric network,which is critical to their superior features,such as self-healing and reprocessing.Herein,we introduce an ionic liquid to dimethylglyoximeurethane(DOU)-based CANs to regulate both reversible bond dynamics and polymer chain mobility by cooperative chemical coupling and physical lubrication.Small-molecule model experiments demonstrated that ionic liquids can catalyze dynamic DOU bond exchange.Ionic liquid also breaks the hydrogen bonds between polymeric chains,thereby increasing their mobility.As a combined result,the activation energy of the dissociation of the dynamic network decreased from 110 to 85 kJ mol^(−1).Furthermore,as a functional moiety,the ionic liquid imparts new properties to CANs and will greatly expand their applications.For example,the consequent conductivity of resultant ionic CAN(iCAN)has demonstrated a great power to build high-performance multifunctional wearable electronics responsive to multiple stimulations including temperature,strain,and humidity.This study provides a new design principle that simultaneously uses the chemical and physical effects of two structural components to regulate material properties enabling novel applications. 展开更多
关键词 covalent adaptable networks POLYURETHANE SELF-HEALING recycling ionic skin
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A Strong and Rigid Coordination Adaptable Network that Can Be Reprocessed and Recycled at Mild Conditions 被引量:2
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作者 Wen Li Hong-Qin Wang +4 位作者 Wen-Tong Gao Zhangxia Wang Pan Xu Haibo Ma Cheng-Hui Li 《CCS Chemistry》 CAS 2022年第12期3781-3797,共17页
The investigation of covalent adaptable networks(CANs)is expanding rapidly due to the growing demand for sustainable materials,as CANs show thermoset-like behavior and yet can be reprocessed,recycled,and healed.Howeve... The investigation of covalent adaptable networks(CANs)is expanding rapidly due to the growing demand for sustainable materials,as CANs show thermoset-like behavior and yet can be reprocessed,recycled,and healed.However,most of the CANs reported so far have a trade-off between mechanical strength and reversible properties and often show performance reduction after reprocessing and/or recycling.Herein,we designed and synthesized a coordination adaptable network(CoAN)by crosslinking low-molecular-weight monomers with abundant coordination bonds.Owning to its excellent variable-stiffness property,leading to high stiffness at ambient conditions and low viscosity at elevated temperature,the as-prepared CoAN showed high mechanical rigidity but could be reprocessed rapidly and recycled at mild conditions.After reprocessing or recycling,the mechanical properties of the samples showed no performance reduction,compared with a pristine sample.Density functional theory calculations showed that free thiol ligands played a key role in reducing the activation energy for bond exchange.When used as binders for composites,the embedded carbon fibers could be recycled rapidly and still maintain the original microstructure.The material also showed temperature-sensitive dielectric and conductive properties due to the release of metal ions upon heating.Overall,such performances are superior among the CANs reported previously. 展开更多
关键词 covalent adaptable networks coordination bond RECYCLE reprocess SELF-HEALING
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Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity
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作者 Moawiah M.Naffaa 《Neural Regeneration Research》 SCIE CAS 2025年第6期1565-1581,共17页
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh... Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior. 展开更多
关键词 network adaptability NEUROGENESIS neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity
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