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SYNTHESIS OF A NOVEL AMPHIPHILE, 4-[4-(4-DECYLOXYPHENYLAZO) NAPHTHYLOXY] BUTYL TRIMETHYLAMMONIUM BROMIDE, AND ITS SELF-ASSEMBLING BEHAVIOR IN DILUTE AQUEOUS SOLUTION
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作者 Guo Wen LI, Xue Wen HU, Hong DING and Ying Qiu LIANG Institute of Theoretical Chemistry, Jilin University, Changchun 130023 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期817-820,共4页
A novel amphiphile of 4-[4-(4-decyloxyphenylazo) naphthyloxy] butyl trimethylammonium bromide has been synthesized. It can form the stable bilayer in dilute aqueous solution.
关键词 AND ITS self-assembling behavior IN DILUTE AQUEOUS SOLUTION BUTYL TRIMETHYLAMMONIUM BROMIDE DECYLOXYPHENYLAZO NAPHTHYLOXY SYNTHESIS OF A NOVEL AMPHIPHILE ITS
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Self-assembling Behavior of Amphiphilic Copolymer Containing Cross-linked Hydrophilic Block in Ethanol
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作者 WANG Ying ZHANG Jun-hu WANG Zhan-hua ZHANG Kai WANG Zheng YU Wen-zhi YANG Bai 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期101-104,共4页
The self-assembly behavior of the amphiphilic block copolymer poly( methyl methacrylate) -block-poly( lead dimethacrylate) (PMMA-b-PLDMA) with cross-linked hydrophilic block(PLDMA) in ethanol was investigated.... The self-assembly behavior of the amphiphilic block copolymer poly( methyl methacrylate) -block-poly( lead dimethacrylate) (PMMA-b-PLDMA) with cross-linked hydrophilic block(PLDMA) in ethanol was investigated. The results show that the size and morphology of the resulting micelle or micellar aggregates are ascribed to the content of ethanol and the nature of the solvent mixture. PbS nanoparticles were formed in the micelle by in situ reaction with H2S gas. The morphology and size of the self-assembly objects were investigated using scanning electron microscopy (SEM) and transmission electron microscopy(TEM). 展开更多
关键词 Cross-linking ETHANOL PbS nanoparticles self-assemblY
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Alcohol solvent effect on the self-assembly behaviors of lignin oligomers
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作者 Ya Ma Zhicheng Jiang +4 位作者 Yafei Luo Xingjie Guo Xudong Liu Yiping Luo Bi Shi 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期597-603,共7页
The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with th... The interactions between lignin oligomers and solvents determine the behaviors of lignin oligomers self-assembling into uniform lignin nanoparticles(LNPs).Herein,several alcohol solvents,which readily interact with the lignin oligomers,were adopted to study their effects during solvent shifting process for LNPs’production.The lignin oligomers with widely distributed molecular weight and abundant guaiacyl units were extracted from wood waste(mainly consists of pine wood),exerting outstanding self-assembly capability.Uniform and spherical LNPs were generated in H_(2)O-n-propanol cosolvent,whereas irregular LNPs were obtained in H_(2)O-methanol cosolvent.The unsatisfactory self-assembly performance of the lignin oligomers in H_(2)O-methanol cosolvent could be attributed to two aspects.On one hand,for the initial dissolution state,the distinguishing Hansen solubility parameter and polarity between methanol solvent and lignin oligomers resulted in the poor dispersion of the lignin oligomers.On the other hand,strong hydrogen bonds between methanol solvent and lignin oligomers during solvent shifting process,hindered the interactions among the lignin oligomers for self-assembly. 展开更多
关键词 Lignin oligomers Alcohol solvent self-assemblY LNPs Solvent effects
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Unveiling the brain’s symphony:exploring the necessity and sufficiency of neural networks in behavior control
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作者 Fernando Jose Bustos 《Neural Regeneration Research》 SCIE CAS 2025年第1期186-187,共2页
Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully a... Since the pioneering work by Broca and Wernicke in the 19th century,who examined individuals with brain lesions to associate them with specific behaviors,it was evident that behaviors are complex and cannot be fully attributable to specific brain areas alone.Instead,they involve connectivity among brain areas,whether close or distant.At that time,this approach was considered the optimal way to dissect brain circuitry and function.These pioneering efforts opened the field to explore the necessity or sufficiency of brain areas in controlling behavior and hence dissecting brain function.However,the connectivity of the brain and the mechanisms through which various brain regions regulate specific behaviors,either individually or collaboratively,remain largely elusive.Utilizing animal models,researchers have endeavored to unravel the necessity or sufficiency of specific brain areas in influencing behavior;however,no clear associations have been firmly established. 展开更多
关键词 behavior CONNECTIVITY neural
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Effect of substituents on self-assembling behaviors and charge transport properties of nonplanar heterocycloarenes
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作者 Jiangyu Zhu Wenhao Li +3 位作者 Rong Zhang Yan Zhao Xuefeng Lu Yunqi Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第10期2903-2911,共9页
(Hetero)cycloarenes possessing rigid molecular skeletons and largeπ-systems are the potential active materials in various electronic devices.However,the development of their organic electronics still lags far behind ... (Hetero)cycloarenes possessing rigid molecular skeletons and largeπ-systems are the potential active materials in various electronic devices.However,the development of their organic electronics still lags far behind the synthetic chemistry.Herein,in order to bridge this gap,we reported the study of organic semiconductor materials based on heterocycloarenes in detail about the relationship between structure,properties,and device performance.Three varying straight alkyl chain substituted butterflyshaped heterocycloarenes PTZs were strategically synthesized.Compared with bulky aryl(mesityl)substituted PTZ1,PTZs show additional self-assembly behavior.Concentration-dependent^(1)H NMR spectra indicated that the self-assembly behavior can be modulated by the alkyl chain length.Medium alkyl chain length substituted heterocycloarene PTZ-C6 showed the strongest association constants of 490 M^(–1)in solution,and a similar trend was also observed in solid state by thin film absorption spectra.Remarkably,despite the nonplanar conjugated backbones,solution-processing thin film transistor based on PTZ-C6 exhibits hole mobility up to 0.13 cm^(2)V^(–1)s^(–1)and considerable current on/off ratio of 10^(5).Our study demonstrates that substituent engineering of heterocycloarenes is a powerful strategy for modulating self-assembling structures and promoting transistor device performance. 展开更多
关键词 heterocycloarenes self-assembling organic semiconductor organic thin film transistor
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Machine Learning Techniques in Predicting Hot Deformation Behavior of Metallic Materials
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作者 Petr Opela Josef Walek Jaromír Kopecek 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期713-732,共20页
In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot al... In engineering practice,it is often necessary to determine functional relationships between dependent and independent variables.These relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable solutions.Nevertheless,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely explored.This study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic materials.The ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree Regression(DTR),and Gaussian Process Regression(GPR)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon steel.Although the GPR method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis. 展开更多
关键词 Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior
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Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior
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作者 Xirong Xu Shoumin Xuan +3 位作者 Shuai Chen Dan Liu Qian Xiao Jie Tu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1721-1734,共14页
The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain functio... The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders. 展开更多
关键词 ANXIETY ASTROCYTES basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry GLUTAMATE LDN-212320 TRANSPORTER
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Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis
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作者 Zhi-Wei Fu Yue-Jing Li +3 位作者 Ran Yu Rui-Qing Guo Li-Xia Gao Sheng-Xia Zhao 《World Journal of Psychiatry》 SCIE 2025年第1期128-136,共9页
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu... BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children. 展开更多
关键词 Preschool children Parenting stress Children's behavioral and emotional problems Family rearing Mediating effect
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Effect of water content on corrosion inhibition behavior of self-assembled TDPA on aluminum alloy surface 被引量:1
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作者 屈钧娥 陈庚 +1 位作者 王海人 聂德键 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3137-3144,共8页
Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water co... Self assembled monolayers (SAMs) of 1-tetradecylphosphonic acids (TDPA, CH3(CH2)13P(O)(OH)2 ) were formed on the 2024 aluminum alloy surface in TDPA-containing ethanol-water solutions with different water content. The adsorption and corrosion protection properties of the SAMs for 2024 alloy in 0.1 mol/L H2SO4 solution were examined and characterized by potentiodynamic polarization, electrochemical impedance spectrum (EIS), Fourier transformed infrared spectroscopy (FTIR), Auger electron spectra (AES) and atomic force microscopy (AFM). FTIR and AES results show that the TDPA molecules were successfully adsorbed on the 2024 aluminum alloy surface, and the density of the SAMs increased with the increasing water content in the assembly solution. The results of electrochemical studies and corrosion morphologies observed by AFM show that a 4 h modification resulted in maximal inhibition efficiency, and the higher the water content in the assembly solution is, the better the inhibition performance of the SAMs can be achieved. The effect of water content in TDPA solutions on the performance of the SAMs is related to the hydration reaction of the metal surface. 展开更多
关键词 1-tetradecylphosphonic acid self-assembled monolayer aluminum alloys corrosion inhibition water content
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The Self-assembling and Application of Inorganic Anti-bacterial Material Made of Natural Nanoporous Carrier 被引量:2
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作者 孙春宝 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第6期771-774,共4页
The inorganic antimicrobial material was inhibited to the microbes with the added metal ion,Zn.The primary wet product carrying 5%-10% zinc ion was generated under the following conditions:temperature was 95 ℃,solut... The inorganic antimicrobial material was inhibited to the microbes with the added metal ion,Zn.The primary wet product carrying 5%-10% zinc ion was generated under the following conditions:temperature was 95 ℃,solution zinc concentration was 1.2-2.0 mol/L,and the ratio of Zn solution to zeolite weight was 5:1.The final stable product was manufactured after baking in an oven for 1-3 h at the temperature of 500-900 ℃.The baked material was tested for its disinfection effectiveness and coloring effect when mixed with paint coating.Based on the final batch of tests,the zinc content of this anti-microbial product was further optimized. 展开更多
关键词 inorganic antimicrobial nanoporous material antibacterial coating ZEOLITE self-assembling
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Electrochemical Behavior and Determination of Trifluoperazine at Decanethiol Self-Assembled Monolayer Modified Gold Electrodes 被引量:1
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作者 HUANGFei YANQuan-ping ZENGBai-zhao 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第2期435-440,共6页
The electrochemical behavior of trifluoperazine at decanethiol self-assembledmonolayer (SAM) modified gold electrodes (i. e. C_(10) H_(21) SH/Au) has been studied,Trifluoperazine can effectively accumulate on C_(10) H... The electrochemical behavior of trifluoperazine at decanethiol self-assembledmonolayer (SAM) modified gold electrodes (i. e. C_(10) H_(21) SH/Au) has been studied,Trifluoperazine can effectively accumulate on C_(10) H_(21) SH/Au electrodes and generate asensitive anodic peak at about 0.63 V (vs. SCE) in 0.05 mol/L pH 9.4 Na_2 B_4 O_7 buffer solution.Under the selected conditions, the anodic peak current was linear to trifluoperazine concentrationin the range of 5.0 X 10^(-7)-3.O X 10^(-3) mol/Lwith correlation coefficient of 0.997, thedetection limit was 3.0 X 10^(-5) mol/L. This method was applied to the determination oftrifluoperazine in drug samples and the recovery was 97.3%-104.0% It was found that sodium dodecylsulfate (SDS) could make the anodic peak current increase. In the presence of SDS, the peak at about0.63 V turned into two peaks, resulting from the change of the electrochemical mechanism. 展开更多
关键词 TRIFLUOPERAZINE DECANETHIOL gold electrodes self-assembled monolayer
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Synthesis and Self-assembling of Coumarin-based Low-molecular Weight Organogelators 被引量:1
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作者 CHEN Guo-jun XUE Peng-chong LU Ran SONG Dong-po BAO Chun-yan XU Ting-hua ZHAO Ying-ying 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第2期178-182,共5页
Four coumarin derivatives(4a-4d) with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organ... Four coumarin derivatives(4a-4d) with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2+2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials. 展开更多
关键词 COUMARIN ORGANOGELATOR self-assembling [2+2] Cyclo-addition
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Effects of 1,7-Bromine Substitution at Bay Area on Self-assembly Behavior and Photo Physical Properties of Perylene Diimide 被引量:1
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作者 曾婷 吴佩跃 +3 位作者 张新林 王洛 孙宾 朱美芳 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期372-378,共7页
N,N'-bis( n-dodecyl)-3,4: 9,10-tetracarboxyl-diimide( 1,7-H-PDI-C12) and its bay position 1,7-Br substituted derivative have been synthesized and characterized by1H-NMR,13C-NMR,FT-IR,and X-ray diffraction( XRD). A... N,N'-bis( n-dodecyl)-3,4: 9,10-tetracarboxyl-diimide( 1,7-H-PDI-C12) and its bay position 1,7-Br substituted derivative have been synthesized and characterized by1H-NMR,13C-NMR,FT-IR,and X-ray diffraction( XRD). A comparison of the two samples by measuring their photo physical properties using UV visible absorption and fluorescence emission spectra revealed that bay substitutions of bromine do not have significant effect on the perylene diimide( PDI) photo physical properties in solution. However,the solid state fluorescence properties were enhanced by brominating at bay areas. The solid fluorescence quantum yield of 1,7-Br-PDI-C12 was 2. 83%( Фf= 2. 83%) and 1,7-H-PDI-C12 was only 0. 02%( Фf= 0. 02%). This behavior was also reflected in the steady-state fluorescence spectra. This work shows that solid state photo physical properties of PDI could be improved without changing the other properties by simply using bromine substitution at bay areas. These types of materials are useful intermediate for further synthesis of PDI with tunnable optoelectronic properties. 展开更多
关键词 disubstituted perylene diimide(PDI) self-assemblY absorption fluorescence
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Chondrogenesis of Precartilaginous Stem Cells in KLD-12 Self-assembling Peptide Nanofiber Scaffold Loading TGF-β3 Gene 被引量:1
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作者 游洪波 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第4期634-640,共7页
The effect of culture in KLD-12 self-assembling peptide nanofiber scaffold containing TGF-β3 gene on differentiation of precartilaginous stem cells (PSCs) into chondrocytes was studied. KLD-12 was synthesized by so... The effect of culture in KLD-12 self-assembling peptide nanofiber scaffold containing TGF-β3 gene on differentiation of precartilaginous stem cells (PSCs) into chondrocytes was studied. KLD-12 was synthesized by solid-state method. After TGF-β3 plasmid was loaded into KLD-12 self-assembling peptide nanofiber scaffold, DNA release ability was investigated. PSCs and hTGF-β3 gene were loaded into KLD-12 3-D scaffold, and MTT assay was performed to investigate the cell proliferation, and ELASA assay was used to investigate the expression of TGF-β3. Specific cartilage matrix was examined by quantitative real-time PCR, immunohistochemistry and Alcian Blue staining. Compared with control group, DNA synthesis level of PSCs reached the peak within 3 days when PSCs were cultured in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, and maintained this high level within 2 weeks. MTT results showed that the proliferation ability of experimental group was statistically higher than that in control group (P〈0.05). Quantitative real-time PCR suggested that the percentage of TGF-β3 positive PSCs in experimental group was higher than that in control group (P〈0.01). ELISA assay showed that the TGF-β3 protein level increased in supernatant of experimental group's PSCs, reached the peak after 72 h and then declined a little to the plateau phase. Compared with the control group, the specific gene of chondrocyte typical extracellular matrix significantly up-regulated (P〈0.01). The results showed that PSCs differentiated into chondrocytes in self-assembling peptide nanofiber scaffold loading TGF-β3 plasmid, which provided a fresh approach to cartilage tissue engineering. 展开更多
关键词 precartilaginous stem cells tissue engineering SCAFFOLD GENE self-assembled peptide transforming growth factor
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A novel artificial nerve graft for repairing longdistance sciatic nerve defects:a self-assembling peptide nanofiber scaffold-containing poly (lactic-co-glycolic acid) conduit 被引量:5
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作者 Xianghai Wang Mengjie Pan +7 位作者 Jinkun Wen Yinjuan Tang Audra D.Hamilton Yuanyuan Li Changhui Qian Zhongying Liu Wutian Wu Jiasong Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第24期2132-2141,共10页
In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-... In this study, we developed a novel artificial nerve graft termed self-assembling peptide nanofiber scaffold (SAPNS)-containing poly(lactic-co-glycolic acid) (PLGA) conduit (SPC) and used it to bridge a 10-mm-long sciatic nerve defect in the rat. Retrograde tracing, behavioral testing and histomorphometric analyses showed that compared with the empty PLGA conduit implantation group, the SPC implantation group had a larger number of growing and extending axons, a markedly increased diameter of regenerated axons and a greater thickness of the myelin sheath in the conduit. Furthermore, there was an increase in the size of the neuromuscular junction and myofiber diameter in the target muscle. These findings suggest that the novel artificial SPC nerve graft can promote axonal regeneration and remyelination in the transected peripheral nerve and can be used for repairing peripheral nerve injury. 展开更多
关键词 nerve regeneration peripheral nerve defect artificial nerve graft poly(lactic-co-glycolic acid) self-assembling peptide nanofiber scaffold REMYELINATION axon myelin neuromuscular junction NSFC grants neural regeneration
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Thermoreversible Thickening and Self-assembly Behaviors of pH/Temperature Dually Responsive Microgels with Interpenetrating Polymer Network Structure 被引量:1
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作者 刘晓云 杨军 +1 位作者 闫伟霞 査刘生 《Journal of Donghua University(English Edition)》 EI CAS 2014年第3期312-315,共4页
The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN micr... The pH /temperature dually responsive microgels of interpenetrating polymer network( IPN) structure composed of poly( N-isopropylacrylamide)( PNIPAM) network and poly( acrylic acid)( PAA) network( PNIPAM /PAA IPN microgels) were synthesized by seed emulsion polymerization. The results obtained by dynamic laser light scattering( DLLS) show that the microgels have good pH /temperature dual sensitivities. The temperature sensitive component and the pH sensitive component inside the microgels have little interference with each other. The rheological properties of the concentrated PNIPAM /PAA IPN microgel dispersions as a function of temperature at pH 4. 0 or 7. 0 were investigated by viscometer,and the results displayed that only at pH 7. 0 the dispersions presented thermoreversible thickening behavior. Then the PNIPAM /PAA fibers were prepared by self-assembly of the PNIPAM /PAA IPN microgels in the ice-crystal templates formed by unidirectional liquid nitrogen freezing method. Field emission scanning electron microscopy( FESEM) images indicate that the PNIPAM /PAA fibers are rounded,randomly orientated and interweaved. 展开更多
关键词 interpenetrating polymer network(IPN) structure pH and temperature sensitivity thermo-thickening self-assembly
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The Channel Behavior of Gramicidin D in the Self-assembled Monolayer
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作者 Ji Dong GUO Li Xiang WANG +2 位作者 Gong Quan SUN Tian Hong LU Hut YANG(Changqhun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022)(Department of Chemistry, Naming Normal University, Naming, 210097) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第2期165-166,共2页
It was found for the first time that gramicidin D (GD) molecules can be incorporated into the ODM monolayer which is self-assembled on the surface of the gold electrode and form monovalent cation channels.
关键词 GRAMICIDIN self-assembled monolayer channel behavior
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Self-assembling peptide nanofibrous hydrogel as a promising strategy in nerve repair after traumatic injury in the nervous system 被引量:1
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作者 Na Zhang Liumin He Wutian Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第5期717-718,共2页
Following injury in central nervous system(CNS),there are pathological changes in the injured region,which include neuronal death,axonal damage and demyelination,inflammatory response and activation of glial cells.T... Following injury in central nervous system(CNS),there are pathological changes in the injured region,which include neuronal death,axonal damage and demyelination,inflammatory response and activation of glial cells.The proliferation of a large number of astrocytes results in the formation of glial scar. 展开更多
关键词 NSCs self-assembling peptide nanofibrous hydrogel as a promising strategy in nerve repair after traumatic injury in the nervous system RGD
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Influence of heat treatment on microstructure,mechanical and corrosion behavior of WE43 alloy fabricated by laser-beam powder bed fusion 被引量:6
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作者 Chenrong Ling Qiang Li +6 位作者 Zhe Zhang Youwen Yang Wenhao Zhou Wenlong Chen Zhi Dong Chunrong Pan Cijun Shuai 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期258-275,共18页
Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.Howe... Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.However,the as-built part usually exhibits undesirable microstructure and unsatisfactory performance.In this work,WE43 parts were firstly fabricated by PBF-LB and then subjected to heat treatment.Although a high densification rate of 99.91%was achieved using suitable processes,the as-built parts exhibited anisotropic and layeredmicrostructure with heterogeneously precipitated Nd-rich intermetallic.After heat treatment,fine and nano-scaled Mg24Y5particles were precipitated.Meanwhile,theα-Mg grainsunderwent recrystallization and turned coarsened slightly,which effectively weakened thetexture intensity and reduced the anisotropy.As a consequence,the yield strength and ultimate tensile strength were significantly improved to(250.2±3.5)MPa and(312±3.7)MPa,respectively,while the elongation was still maintained at a high level of 15.2%.Furthermore,the homogenized microstructure reduced the tendency of localized corrosion and favoredthe development of uniform passivation film.Thus,the degradation rate of WE43 parts was decreased by an order of magnitude.Besides,in-vitro cell experiments proved their favorable biocompatibility. 展开更多
关键词 laser-beam powder bed fusion WE43 alloys heat treatment mechanical performance biodegradation behavior
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BCCLR:A Skeleton-Based Action Recognition with Graph Convolutional Network Combining Behavior Dependence and Context Clues 被引量:3
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作者 Yunhe Wang Yuxin Xia Shuai Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期4489-4507,共19页
In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal ... In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal graph.Most GCNs define the graph topology by physical relations of the human joints.However,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint pairs.In addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar poses.Therefore,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint pairs.By using the weight relationship between the joint pairs,an adaptive model is constructed.It also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of actions.Combining the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar poses.Detailed experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods. 展开更多
关键词 Action recognition deep learning GCN behavior dependence context clue self-attention
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