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基于符号互动论的红色档案文创产品开发增效研究
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作者 王阿陶 杜雨夏 《档案与建设》 2026年第1期52-59,共8页
符号互动论作为强调个体在社会互动中赋予并重构符号意义的社会学理论,为提升红色档案文创产品开发的效能提供了新的分析视角。文章通过对红色档案文创产品符号属性的剖析,揭示其在开发过程中与符号互动论内在的契合逻辑,进而分析当前... 符号互动论作为强调个体在社会互动中赋予并重构符号意义的社会学理论,为提升红色档案文创产品开发的效能提供了新的分析视角。文章通过对红色档案文创产品符号属性的剖析,揭示其在开发过程中与符号互动论内在的契合逻辑,进而分析当前红色档案文创产品存在的符号内容浅表化、社会互动赋义不足、符号活力受限、情感共鸣缺失等困境,提出基于符号互动论的深化符号内涵挖掘、激发社会多元参与、激活符号持续更新与强化用户情感连接的红色档案文创产品开发增效策略,发挥红色档案在弘扬民族精神、传承红色基因中的价值。 展开更多
关键词 符号互动论 红色档案 文创产品 产品开发
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生命时间结构:教师发展理论研究的一种新视野
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作者 曹永国 《教师发展研究》 2026年第1期83-89,共7页
教师发展理论研究主要有三种路向:一是教师发展的阶段化研究路向,它将教师发展看成普遍存在的阶段性进程,是一种对教师发展的程式化设想;二是教师发展的生命历程研究路向,它将教师发展理解为其生命中的重大事件、社会变迁、文化结构等... 教师发展理论研究主要有三种路向:一是教师发展的阶段化研究路向,它将教师发展看成普遍存在的阶段性进程,是一种对教师发展的程式化设想;二是教师发展的生命历程研究路向,它将教师发展理解为其生命中的重大事件、社会变迁、文化结构等对其形塑过程;三是教师发展的本体论研究路向,它将教师发展视为教师自身的精神成长及其对教育意义的寻求过程。这三种研究路向或失之于静态化描绘,或失之于单一视角勾画。生命时间结构则提供了一个更为完整的研究路向,其连接了社会规划与个体能动,能够剖析时间结构变化中社会结构的运转与教师行为安排、生命意义筹划之关系,揭示现代时间结构中教师的生命处境和时间应对,是教师发展理论研究的一种新视野。 展开更多
关键词 生命时间结构 教师发展理论 互动论 生命历程 加速社会
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Geometric control of concurrence and quantum gate operations in triangular triple quantum dots
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作者 Junqing Li Shuo Dong Jianhua Wei 《Chinese Physics B》 2026年第2期314-321,共8页
As an important index to measure the degree of entanglement in quantum systems,concurrence plays an important role in practical research.In this paper,we study the concurrence between two qubits in triangular triple q... As an important index to measure the degree of entanglement in quantum systems,concurrence plays an important role in practical research.In this paper,we study the concurrence between two qubits in triangular triple quantum dot structure.Through calculation and simulation,it is found that concurrence is mainly affected by the interdot coupling strength t,Coulomb interactionU,temperature T,and electrode coupling G.Through comparative studies with parallel triple quantum dot structures,we demonstrate that the triangular geometry exhibits significantly enhanced concurrence under identical conditions.In addition,under the condition that concurrence exceeds 0.9,the functional relationship between t and U is obtained through simulation,which provides theoretical support for quantum dot regulation under high entanglement.Finally,we demonstrate the feasibility of implementing a three-qubit quantum gate,using the Toffoli gate as a representative example,under the condition that the triangular triple quantum dot system maintains high entanglement. 展开更多
关键词 transition coupling interaction triangular triple quantum dots quantum entanglement Coulomb interaction quantum computing
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DFT Insights into the Detection of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)Gases with Pristine and Monovacancy Phosphorene Sheets
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作者 Naresh Kumar Anuj Kumar Abhishek K.Mishra 《Computers, Materials & Continua》 2026年第4期517-531,共15页
Density functional theory(DFT)calculations were employed to investigate the adsorption behavior of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)molecules on both pristine and mono-vacancy phosphorene sheets.The pristine pho... Density functional theory(DFT)calculations were employed to investigate the adsorption behavior of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)molecules on both pristine and mono-vacancy phosphorene sheets.The pristine phosphorene surface showsweak physisorption with all the gasmolecules,inducing onlyminor changes in its structural and electronic properties.However,the introduction ofmono-vacancies significantly enhances the interaction strength with NH_(3),PH_(3),CO_(2),and CH_(4).These variations are attributed to substantial charge redistribution and orbital hybridization in the presence of defects.The defective phosphorene sheet also exhibits enhanced adsorption energies,along with favorable sensitivity and recovery characteristics,highlighting its potential as a promising gas sensor for NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)at ambient conditions. 展开更多
关键词 Phosphorene VACANCY defects DFT interaction sensitivity
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Host-vip interaction mediated low-shrinkage photosensitive positioning adhesive
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作者 Zhao Liu Junjian Xie +3 位作者 Xiaoming Ren Muhammad Tahir Shixin Fa Qiuyu Zhang 《Chinese Chemical Letters》 2026年第2期501-504,共4页
As a common electronic adhesive,ultraviolet(UV)curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane,excellent weather resistance and optical properties of acrylate.Despite the... As a common electronic adhesive,ultraviolet(UV)curing polyurethane acrylate adhesive has both flexibility and wear resistance of polyurethane,excellent weather resistance and optical properties of acrylate.Despite the extensive applications,it is still difficult to solve the problems caused by the shrinkage of adhesive.Here,a new type of photosensitive adhesive for bonding electronic components based on supramolecular interaction was designed and synthesized.The supramolecular interaction of cyclodextrin and adamantane moieties introduced into the adhesive polymer entitles the viscosity of the adhesive to rise rapidly during use,thereby preventing adhesive loss and dislocation of electronic components.UV light could further cure the adhesive and position the electronic components.The adhesive shrunk<2%when cured by UV light,so it can be used for electronic packaging and high-resolution,defect-free lithography. 展开更多
关键词 ADHESIVE Host-vip interaction UV-CURING Low-shrinkage LITHOGRAPHY
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Characterization of the interaction between human cytochrome c and transfer RNAphe
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作者 Guangqing Zhang Jianhua Zhan +4 位作者 Xin Chai Bin Jiang Maili Liu Xu Zhang Danyun Zeng 《Magnetic Resonance Letters》 2026年第1期1-12,共12页
Cytochrome c(cyt c)is released from mitochondria into the cytosol upon apoptotic stimulation,ultimately triggering programmed cell death.Recent studies have revealed that transfer RNA(tRNA)interacts with cyt c,impedin... Cytochrome c(cyt c)is released from mitochondria into the cytosol upon apoptotic stimulation,ultimately triggering programmed cell death.Recent studies have revealed that transfer RNA(tRNA)interacts with cyt c,impeding the formation of the apoptosome complex and thereby suppressing apoptosis.To elucidate the molecular mechanism underlying the interaction between cyt c and tRNA,nuclear magnetic resonance(NMR)-based chemical shift perturbation and intensity analysis were employed to characterize the binding interface between cyt c and tRNAphe.The findings demonstrate that cyt c primarily engages with tRNAphe through its 70–85Ω-loop and N-terminalα-helix.This interaction sterically hinders the accessibility of small molecules,such as H_(2)O_(2),to the hydrophobic pocket of cyt c,consequently attenuating its peroxidase activity.Furthermore,oxidative modification of cyt c,particularly the carbonylation of positively charged lysine residues,weakens this interaction. 展开更多
关键词 INTERACTION NMR Cytochrome c TRNA Oxidative modification
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Assessing the photoluminescence of metal nanoclusters:The individual versus the collective
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作者 Xiaoqin Du Peiyao Pan +4 位作者 Haoqi Li Di Zhang Wentao Huang Xi Kang Manzhou Zhu 《Chinese Chemical Letters》 2026年第2期559-563,共5页
Understanding the photoluminescence(PL)mechanism of metal nanoclusters from both molecular and supramolecular perspectives is crucial for developing highly emissive cluster-based nanomaterials.In this study,we synthes... Understanding the photoluminescence(PL)mechanism of metal nanoclusters from both molecular and supramolecular perspectives is crucial for developing highly emissive cluster-based nanomaterials.In this study,we synthesized two structurally similar Ag14 nanoclusters with different phosphine stabilizers,which demonstrated opposite PL behaviors in solution and crystalline states.The Ag14 nanocluster stabilized by P(Ph-OMe)_(3) ligands exhibited a higher PL intensity compared to the one stabilized by P(Ph-F)_(3) ligands,which was attributed to the stronger electron-donating ability of the P(Ph-OMe)_(3) ligand that improved ligand-to-metal charge transfer efficiency.In contrast,the P(Ph-F)_(3) stabilized Ag14 crystals displayed greater PL intensity than the Ag14 cluster crystal with a-OMe surface,which was due to stronger intermolecular interactions within the cluster lattice of the former that limited non-radiative energy loss and thus enhanced PL.Overall,this work aims to promote a comprehensive understanding of the fluorescence in cluster-based nanomaterials,which will be beneficial for their downstream applications. 展开更多
关键词 NANOCLUSTER PHOTOLUMINESCENCE Crystal structure Ligand effect Intermolecular interaction
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Home Mealtimes in Kenya and Zambia:Recognising culturally grounded practices that foster healthy eating behaviours
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作者 Jeofrey Mtemeri Hetal Patel +7 位作者 Rehema Abiyo Claire Farrow Megan Jarman Haatembo Mooya Laura Shapiro Barnabas Simatende Pamela Wadende Henriette Zeidler 《Journal of Psychology in Africa》 2026年第1期53-63,共11页
Globally,mealtimes provide key insights into cultural and social values and practices.We examine mealtime environments and eating practices in two different African settings using quantitative observational and questi... Globally,mealtimes provide key insights into cultural and social values and practices.We examine mealtime environments and eating practices in two different African settings using quantitative observational and questionnaire data.Participating families(N=80)were recruited from two rural locations in Zambia and Kenya.Results following descriptive analysis showed that meals are typically taken as a family in a sociable context,providing opportunities to nurture children’s positive behaviours.In both communities,mothers(71.25%)were most likely to be present and typically prepared meals and provided the food.We observed a few distractions being used during mealtimes,and children finished their food with little to no conflict.Plate sharing varied across the two sites and was more common in Zambia,where we also observed more traditional practices such as eating with hands(as opposed to cutlery)and sitting on mats on the ground(as opposed to seated on chairs or sofas).Overall,our findings suggest more similarities in the cultural and social values across the two African contexts despite slight differences in mealtime practices.In particular,positive mealtime behaviours(little food refusal,lack of conflict)were common across all contexts,regardless of the extent to which traditional practices(such as plate-sharing and sitting on the floor)were used.Findings align with Family Systems theory,which states that the family is understood best by conceptualizing it as a complex,dynamic,and changing collection of parts,subsystems,and family members. 展开更多
关键词 Detractors LUNCH parent-child interaction eating behaviour feeding practices
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Keystone Fungal Endophytes of Panax Plants Drive the Conversion of Ginsenoside Rb1 to Rd
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作者 Ruikang Ma Guangfei Wei +5 位作者 Songzi Li Tongle Li Fugang Wei Yong Wang Guozhuang Zhang Linlin Dong 《Phyton-International Journal of Experimental Botany》 2026年第2期166-183,共18页
Keystone taxa are critical for microbial community homeostasis and ecological niche interactions.However,the functions and genomic traits of endophytic keystone fungi in plant tissues remain unclear.Via network analys... Keystone taxa are critical for microbial community homeostasis and ecological niche interactions.However,the functions and genomic traits of endophytic keystone fungi in plant tissues remain unclear.Via network analysis,this study identified keystone fungi Plectosphaerella(Plec)and Cladosporium(Clad)in roots/leaves of medicinal Panax plants(P.ginseng,P.quinquefolius,P.notoginseng).Both correlated strongly positively with ginsenoside Rd content in respective tissues(ρ>0.6,p<0.001).Co-cultivation confirmed their ability to convert ginsenoside Rb1 to Rd,linked toβ-glucosidase activity.Whole-genome sequencing/assembly/evolutionary analysis of the two strains elucidated genomic features for their keystone roles and saponin biotransformation.Genome mining found multiple GH3 genes(potential saponin transformers)in both;11(Plec)and 5(Clad)were upregulated by cellobiose.Gene family phylogenetic analysis showed expanded transmembrane transport and environmental response functions.Both also had abundant secondary metabolic gene clusters and secretome genes,linking biotic interaction functions to their keystone roles.In summary,this study shows Panax endophytic keystone fungi can participate in ginsenoside biotransformation and clarifies their genomic traits,offering insights for functional endophytic fungal resource development. 展开更多
关键词 PANAX GINSENOSIDE plant-microbe interaction keystone taxa endophytic fungi
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Traditional Chinese medicine in modulating gut microbiota across major disease systems: a review
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作者 Zhi-Yi Chen Hao-Ran Li +1 位作者 Guang-Wei Xu Xue-Zhu Zhang 《Traditional Medicine Research》 2026年第2期39-55,共17页
Background: The human gut microbiome is an important target for disease treatment and prevention. Various microbial species within the complex ecosystem of the microbiome have been shown to play important roles in dis... Background: The human gut microbiome is an important target for disease treatment and prevention. Various microbial species within the complex ecosystem of the microbiome have been shown to play important roles in disease. Identification of bioactive materials capable of altering the abundances of these species both safely and effectively is a major goal in microbiome research. Many traditional Chinese medicines (TCMs) have been reported to affect the composition of the gut microbiome. Here, we summarize studies that have used TCMs to alter the gut microbiome and discuss the response relationship between TCMs and gut microbial species. Methods: We searched the PubMed, Web of Science, and Knowledge Network databases using the terms “traditional Chinese medicine,” “gut microbiome,” and specific system disease names (endocrine, immune, nervous, cardiovascular, and digestive). Studies were excluded if irrelevant or if the experimental procedures were unclear. Results: TCMs have been reported to affect a wide range of gut microbial taxa spanning major phyla, including Firmicutes, Bacteroidetes, Proteobacteria, Verrucomicrobiota, Actinobacteria, and Fusobacteria. In all, 54 TCMs including compounds and extracts have been tested in rodents and 30 have been examined in human trials. Almost all studies have reported positive results in regulating the gut microbiome as well as modulating corresponding phenotypes, spanning diseases of the endocrine, immune, nervous, cardiovascular, and digestive systems. Gut species, including Akkermansia, Bacteroides, Fusobacterium, Faecalibacterium, and E. coli, were found to be regulated by 19 TCMs. A network was constructed to visualize the interactions between TCMs and these taxa. Conclusion: There exists a complex and close relationship between intestinal microflora and diseases. Sufficient experimental data and studies have proved that the imbalance of intestinal microflora affects health by mediating metabolism, immune regulation, inflammation and signal transduction. Many characteristic alterations of intestinal microflora are positively correlated with diseases, so intestinal microflora has become a potential risk index and treatment target for many diseases. Many TCMs affect the relative abundances of microbial species in the gut, and therefore may be useful for modulating the gut microbiome. This review provides a reference for prioritizing candidate TCMs from the enormous repertoire of such medicines to test which specific gut microbes are targeted. 展开更多
关键词 Chinese herbal intestinal microbiome MICROBIOLOGY intervention studies drug-microbiome interaction
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Oxophilic sites activate asymmetric IrNi atomic dimers and clusters for efficient hydrogen oxidation and CO tolerance
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作者 Mansheng Liao Fangjun Luo +9 位作者 Yuan Zhang Ruoyu Wei Zhongyao Zhang Ruiwen Qi Jun Yu Yongliang Li Xiangzhong Ren Lei Zhang Qianling Zhang Zhongxin Song 《Science China Materials》 2026年第3期1464-1474,共11页
Multi-site coupling is a promising strategy for developing highly efficient and CO-resistant hydrogen oxidation reaction(HOR)catalysts for proton exchange membrane fuel cells(PEMFCs).However,designing multifunctional ... Multi-site coupling is a promising strategy for developing highly efficient and CO-resistant hydrogen oxidation reaction(HOR)catalysts for proton exchange membrane fuel cells(PEMFCs).However,designing multifunctional synergistic schemes for single-atom sites remains a significant challenge.Herein,we propose a dual-template-confined oxophilic engineering strategy to construct well-dispersed iridium-nickel(IrNi)atomic dimers adjacent to IrNi nanoclusters on porous nitrogen-doped carbon(IrNi_(Dimer/NC1.8)-PNC).The paired IrNi dimer features an asymmetric Ir-N_(3)configuration coordinated with heteroatomic Ni-N_(3)O via an N-bridge.Remarkably,IrNi_(Dimer/NC1.8)-PNC exhibits a~23-fold enhancement in mass activity(4.36 A mg-1Ir at 20 mV)and 5-fold longer stability compared to benchmarking Pt/C toward HOR,while achieving a high rated power density of 1.18 W cm^(-2)in PEMFC anode applications.Furthermore,IrNi_(Dimer/NC1.8)-PNC demonstrates superior CO tolerance over monometallic Ir and Pt/C in both half-cell and full-cell devices.Combined experimental and density functional theory studies reveal that oxophilic Ni modulates the electronic environment of Ir through alloying and dimer interactions,thereby enhancing HOR activity.Importantly,the asymmetric IrNi dimer enables efficient CO^(*)and OH^(*)co-adsorption while facilitating CO_(2)^(*)desorption,synergistically mitigating CO poisoning and improving atom utilization efficiency.This work provides a design strategy and fundamental insights for multi-site synergistic catalysts in PEMFC anodes. 展开更多
关键词 IrNi dimer asymmetric coordination synergistic interaction hydrogen oxidation CO tolerance PEMFC
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“Connect”or“drag”?The impact of physiologically relevant inorganic ion pairs on the protein corona adsorption onto liposomes
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作者 Yeqi Huang Yue Gao +8 位作者 Yuxin Lin Yihao Li Si Xiong Xia Guo Chuanbin Wu Xin Pan Wenhao Wang Ziyu Zhao Zhengwei Huang 《Chinese Chemical Letters》 2026年第2期314-318,共5页
The protein corona formation has been reported to influence the liposomes’behavioral performance in vivo.Accordingly,the effect of physiologically relevant inorganic ion pairs(sodium chloride,sodium sulfate,magnesium... The protein corona formation has been reported to influence the liposomes’behavioral performance in vivo.Accordingly,the effect of physiologically relevant inorganic ion pairs(sodium chloride,sodium sulfate,magnesium chloride,and magnesium sulfate)was investigated.Bovine serum albumin(BSA)was selected as the model protein.Parameters including particle size and zeta potential were assessed,while various spectroscopic techniques were utilized to elucidate the changes in BSA during its interaction with liposomes.The particle size and light intensity distribution changes indicated that the introduction of inorganic pairs,especially the metal cations,could significantly influence both the adsorption of BSA and the aggregation of particles.Furthermore,spectral characterization elucidated that BSA exhibited more extended peptide chains with enhanced exposure to hydrophobic acid amino residues upon adding ion pairs.Electrostatic adsorption and chelation insertion were proposed as metal ion binding modes and the corresponding BSA corona formation.In the electrostatic adsorption mode,sodium ions can enhance the electrostatic interactions,facilitating the“connection”between BSA and liposomes.Magnesium ions can induce stronger hydrophobic interactions through chelation,effectively“drag”BSA segments into the lipid bilayer.This work highlighted important physiological factors for protein-liposome interaction and provided rational model constructions to lay the foundation for further relevant studies. 展开更多
关键词 Protein corona Liposomes Inorganic ion Interaction patterns Nanoparticle adsorption profile
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Robotic Security
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作者 GE LIJUN 《ChinAfrica》 2026年第3期57-57,共1页
Embodied intelligence is redefining policing On the first day of 2026 chunyun,a period of high mobility associated with the Chinese New Year,the city of Jingzhou in Hubei Province welcomed new participants in road saf... Embodied intelligence is redefining policing On the first day of 2026 chunyun,a period of high mobility associated with the Chinese New Year,the city of Jingzhou in Hubei Province welcomed new participants in road safety:police robots capable of moving autonomously and interacting with passengers.Deployed on a trial basis on 2 February,these robots quickly demonstrated their usefulness in various urban settings. 展开更多
关键词 PASSENGERS autonomous movement police robots interaction embodied intelligence Chunyun road safety Chinese New Year
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Self-assembled supramolecular nanofibers integrate pH-responsive drug delivery and antimicrobial for combined cancer therapy
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作者 Ting Zhang Deqiang Chen +5 位作者 Ningzhi Zhang Mingxu Zhang Qiang Huang Wei Liu Ran Gao Yong Zhang 《Chinese Chemical Letters》 2026年第2期346-351,共6页
Constructing nanofibers with specific therapeutic effects against cancer is a challenge.Here,we present the synthesis approach and application prospects of supramolecular nanofibers,which are based on cucurbit[8]uril(... Constructing nanofibers with specific therapeutic effects against cancer is a challenge.Here,we present the synthesis approach and application prospects of supramolecular nanofibers,which are based on cucurbit[8]uril(CB[8])as the host and terpyridine lanthanum ions metal complex as the vip,constructed by layer-by-layer self-assembly through supramolecular interaction.Moreover,nanofibers with lanthanide luminescence properties exhibit surprising pH-responsive deformation properties and antibacterial behavior.In the tumor micro-environment,the dramatic reduction in the size of the nanofibers enables specific and hierarchical release of anticancer drugs in tumor cells to exert an advanced therapeutic effect.In addition,the synergistic therapeutic efficacy was achieved by reducing the excess of Gram-positive and Gram-negative bacteria surrounding tumor cells.The novel supramolecular nanofibers with sequential drug release and combined therapeutic mode provide new guidance for the synthesis of drug carrier materials and direction for the promotion of nanomaterial-mediated cancer therapy. 展开更多
关键词 pH-responsive self-assembly nanofibers Supramolecular interaction Sequential release Antibacterial Combination therapy
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Tissue-Specific Transcriptomic Responses and Viral Accumulation in Lily Cultivars Infected with Cucumber Mosaic Virus
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作者 Yun-Im Kang Youn Jung Choi +3 位作者 Su Young Lee Young-Ran Lee Ki-Byung Lim Yun-Jae Ahn 《Phyton-International Journal of Experimental Botany》 2026年第1期103-118,共16页
Cucumber mosaic virus(CMV)threatens lily production by reducing floral quality and enabling carry-over via infected planting stock.To explore tissue-specific host responses,we analyzed a legacy,single-replicate RNA-se... Cucumber mosaic virus(CMV)threatens lily production by reducing floral quality and enabling carry-over via infected planting stock.To explore tissue-specific host responses,we analyzed a legacy,single-replicate RNA-seq dataset from two cultivars,‘Cancun’and‘Connecticut King’(CK),profiling leaf(source)and bulb(sink)tissues at 0 and 28 days post-inoculation(dpi),alongside leaf DAS-ELISA.Principal component analysis indicated that tissue identity dominated the transcriptome(PC1=47.7%),with CMV treatment driving within-tissue shifts over time.Exploratory Gene Ontology/KEGG summaries and a focused marker panel revealed a consistent split:in leaves,genes linked to jasmonate/WRKY-associated defense(e.g.,WRKY40/41/51/53;AOS/OPR1/2;CYP74A/DDE2)tended to show higher expression at 28 dpi,whereas cell-wall/transport-related terms were reduced;in bulbs,transcripts associated with photosynthetic/organellar maintenance(LHCB/CAB,HCF107)andβ-amylase-linked carbohydrate turnover were more prominent,with comparatively limited elevation of canonical defense modules.Leaf ELISA trajectories were compatible with this framework:CK showed a transient peak at 14 dpi followed by a decline at 24 dpi,whereas‘Cancun’increased progressively.Taken together,the concordance among ordination,enrichment patterns,marker behavior,and leaf titers in this non-replicated dataset is consistent with a working model in which stronger or earlier leaf responses may contribute to partial containment and reduced systemic accumulation.We propose a compact leaf marker set(WRKY40/41/51/53;AOS/OPR1/2;CYP74A/DDE2)and bulb candidates(β-amylase;LHCB/CAB/HCF107)as hypothesis-generating indicators of containment and sink maintenance.These tissue-resolved patterns provide a descriptive framework and a starting point for future validation by qPCR and replicated RNA-seq across additional cultivars,with the long-term goal of informing selection and stock hygiene in lily production. 展开更多
关键词 Ornamental geophytes tissue-specific response jasmonate/WRKY SOURCE-SINK breeding markers plant-virus interaction
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Approach for redefining the damping factor of railway bridges with ballast superstructure:model calibration and guidelines for practical application
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作者 Andreas Stollwitzer Samuel Loidl +1 位作者 Lara Bettinelli Josef Fink 《Railway Engineering Science》 2026年第1期97-127,共31页
To ensure the compatibility between rolling stock and infrastructure when dynamically assessing railway bridges under high-speed traffic,the damping properties considered in the calculation model significantly influen... To ensure the compatibility between rolling stock and infrastructure when dynamically assessing railway bridges under high-speed traffic,the damping properties considered in the calculation model significantly influence the predicted acceleration amplitude at resonance.However,due to the normative specifications of EN 1991-2,which are considered to be overly conservative,damping factors that are far below the actual damping have to be used when predicting vibrations of railway bridges,which means that accelerations at resonance tend to be overestimated to an uneconomical extent.Comparisons between damping factors prescribed by the standard and those identified based on in situ structure measurements always reveal a large discrepancy between reality and regulation.Given this background,this contribution presents a novel approach for defining the damping factor of railway bridges with ballasted tracks,where the damping factor for bridges is mathematically determined based on three different two-dimensional mechanical models.The basic principle of the approach for mathematically determining the damping factor is to separately define and superimpose the dissipative contributions of the supporting structure(including the substructure)and the superstructure.Using the results of a measurement campaign on 15 existing steel railway bridges in the Austrian rail network,the presented mechanical models are calibrated,and by analysing the energy dissipation in the ballasted track,guiding principles for practical application are defined.This guideline is intended to establish an alternative to the currently valid specifications of EN 1991-2,enabling the damping factor of railway bridges to be assessed in a realistic range by mathematical calculation and thus without the need for extensive in situ measurements on the individual structure.In this way,the existing potential of the infrastructure with regard to the damping properties of bridges can be utilised.This contribution focuses on steel bridges,but the mathematical approach for determining the damping factor applies equally to other bridge types(concrete,composite,or filler beam). 展开更多
关键词 Railway bridges Bridge dynamics DAMPING Track-bridge interaction Structural health monitoring Condition assessment
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Load of the Small-Scale Vertical Cylinder in a Wave-Current Field
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作者 Mingjie Li Binbin Zhao Wengyang Duan 《哈尔滨工程大学学报(英文版)》 2026年第1期82-94,共13页
Studies of wave-current interactions are vital for the safe design of structures.Regular waves in the presence of uniform,linear shear,and quadratic shear currents are explored by the High-Level Green-Naghdi model in ... Studies of wave-current interactions are vital for the safe design of structures.Regular waves in the presence of uniform,linear shear,and quadratic shear currents are explored by the High-Level Green-Naghdi model in this paper.The five-point central difference method is used for spatial discretization,and the fourth-order Adams predictor-corrector scheme is employed for marching in time.The domain-decomposition method is applied for the wave-current generation and absorption.The effects of currents on the wave profile and velocity field are examined under two conditions:the same velocity of currents at the still-water level and the constant flow volume of currents.Wave profiles and velocity fields demonstrate substantial differences in three types of currents owing to the diverse vertical distribution of current velocity and vorticity.Then,loads on small-scale vertical cylinders subjected to regular waves and three types of background currents with the same flow volume are investigated.The maximum load intensity and load fluctuation amplitude in uniform,linear shear,and quadratic shear currents increase sequentially.The stretched superposition method overestimates the maximum load intensity and load fluctuation amplitude in opposing currents and underestimates these values in following currents.The stretched superposition method obtains a poor approximation for strong nonlinear waves,particularly in the case of the opposing quadratic shear current. 展开更多
关键词 Wave-current interaction Cylinder load HLGN model Morison equation Regular waves
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Hypersonic Flow over V-Shaped Leading Edges:A Review of Shock Interactions and Aerodynamic Loads
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作者 Xinyue Dong Wei Zhao +4 位作者 Jingying Wang Shiyue Zhang Yue Zhou Xinglian Yang Chunhian Lee 《Fluid Dynamics & Materials Processing》 2026年第1期26-44,共19页
For hypersonic air-breathing vehicles,the V-shaped leading edges(VSLEs)of supersonic combustion ramjet(scramjet)inlets experience complex shock interactions and intense aerodynamic loads.This paper provides a comprehe... For hypersonic air-breathing vehicles,the V-shaped leading edges(VSLEs)of supersonic combustion ramjet(scramjet)inlets experience complex shock interactions and intense aerodynamic loads.This paper provides a comprehensive review of flow characteristics at the crotch of VSLEs,with particular focus on the transition of shock interaction types and the variation of wall heat flux under different freestream Mach numbers and geometric configurations.The mechanisms governing shock transition,unsteady oscillations,hysteresis,and three-dimensional effects in VSLE flows are first examined.Subsequently,thermal protection strategies aimed at mitigating extreme heating loads are reviewed,emphasizing their relevance to practical engineering applications.Special attention is given to recent studies addressing thermochemical nonequilibrium effects on VSLE shock interactions,and the limitations of current research are critically assessed.Finally,perspectives for future investigations into hypersonic VSLE shock interactions are outlined,highlighting opportunities for advancing design and thermal management strategies. 展开更多
关键词 V-shaped leading edges shock interaction SCRAMJET thermochemical nonequilibrium aerodynamic heating
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Multi-physical modeling of climate-driven elasto-plastic deformation,stress redistribution,and water potential in desiccation-cracked soils of arid regions
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作者 Milad Jabbarzadeh Hamed Sadeghi 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期772-791,共20页
This study presents a multi-physical modeling approach to analyze the dynamics of moisture potential and stress-deformation features near deep desiccation cracks in clayey soils under three consecutive years’climate ... This study presents a multi-physical modeling approach to analyze the dynamics of moisture potential and stress-deformation features near deep desiccation cracks in clayey soils under three consecutive years’climate variability in an arid region.A triple research approach of statistical analysis,analytical framework,and numerical modeling was used to investigate the complex thermo-hydro-mechanical behavior of desiccation-cracked soil,incorporating realistic climatic data of Qom,Iran.The results revealed the interplay between stress,strain,and pore water pressure over time,demonstrating that soil experiences significant swelling and shrinkage due to cyclic wetting and drying.The horizontal stress distribution shows compressive stress concentration at crack tips during wetting,transitioning to tensile stresses uniformly across the soil surface during drying paths.Similarly,vertical stress distributions exhibit localized compressive stresses along crack boundaries during wetting and tensile stresses during drying,highlighting the critical stress conditions at crack tips.The model differentiates between microstructural and macrostructural changes in porosity.Annual trends in micro-porosity revealed cyclic-dependent behavior,with significant volumetric changes occurring in the first year,stabilizing with successive cycles.The results also indicated that part of the volumetric changes are irreversible,with volumetric plastic strain increasing exponentially but at a decreasing rate over three years.Principal stress analysis indicates a shift from compressive to tensile stress states around cracks,driven by climate-induced wetting and drying cycles.These findings underscore the critical role of climate variability in shaping cracked soil behavior in arid regions,providing insights into the heterogeneous behavior of cracked soil surfFicial layers. 展开更多
关键词 Soil-atmosphere interaction Moisture potential dynamics Stress-deformation characteristics Desiccation cracks Arid climate
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Multiphysics Implicit Coupling Method for Fluid,Particles,and Large-Deformation Structures
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作者 Xiangxiang Wang Hualong Xie +3 位作者 Yue Yu Min Li Yubin Wang Fei Xing 《Computer Modeling in Engineering & Sciences》 2026年第2期367-401,共35页
This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,Calcu... This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,CalculiX,and preCICE to simulate fluid-particle-structure interactions with large deformations.Mesh motion in the fluid field is handled using the radial basis function(RBF)method.The particle phase is modeled by MPPIC,where fluid-particle interaction is described through momentum exchange,and inter-particle collisions are characterized by collision stress.The structural field is solved by nonlinear FEM to capture large deformations induced by geometric nonlinearity.Coupling among fields is realized through a partitioned,parallel,and non-intrusive iterative strategy,ensuring stable transfer and convergence of interface forces and displacements.Notably,the influence of particles on the structure is not direct but mediated by the fluid,while structural motion directly affects particle dynamics.The results demonstrate that the proposed approach effectively captures multiphysics interaction processes and provides a valuable reference for numerical modeling of coupled fluid-particle-structure systems. 展开更多
关键词 Fluid-particle-structure interaction large deformation partitioned method non-intrusive coupling
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