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1.
STAR Protoc ; 5(2): 103029, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38728135

RESUMO

Due to the higher and more rapid consumption of carbohydrates by cancer cells compared to normal cells, carbohydrates can be effectively employed as a targeted therapeutic strategy for tumor treatment. Here, we present a protocol for synthesizing sequence-controlled glycooligomers using both solution-phase and solid-phase systems. We outline detailed procedures for evaluating the safety and tumor-targeting properties of the sequence-controlled glycooligomers in vivo. For complete details on the use and execution of this protocol, please refer to Chen et al.1.

2.
Int J Biol Macromol ; 270(Pt 2): 132181, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38740155

RESUMO

Nowadays, developing vascular grafts (e.g., vascular patches and tubular grafts) is challenging. Bacterial cellulose (BC) with 3D fibrous network has been widely investigated for vascular applications. In this work, different from BC vascular patch cultured with the routine culture medium, dopamine (DA)-containing culture medium is employed to in situ synthesize dense BC fibrous structure with significantly increased fiber diameter and density. Simultaneously, BC fibers are modified by DA during in situ synthesis process. Then DA on BC fibers can self-polymerize into polydopamine (PDA) accompanied with the removal of bacteria in NaOH solution, obtaining PDA-modified dense BC (PDBC) vascular patch. Heparin (Hep) is subsequently covalently immobilized on PDBC fibers to form Hep-immobilized PDBC (Hep@PDBC) vascular patch. The obtained results indicate that Hep@PDBC vascular patch exhibits remarkable tensile and burst strength due to its dense fibrous structure. More importantly, compared with BC and PDBC vascular patches, Hep@PDBC vascular patch not only displays reduced platelet adhesion and improved anticoagulation activity, but also promotes the proliferation, adhesion, spreading, and protein expression of human umbilical vein endothelial cells, contributing to the endothelialization process. The combined strategy of in situ densification and Hep immobilization provides a feasible guidance for the construction of BC-based vascular patches.

3.
Bioengineering (Basel) ; 11(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38671729

RESUMO

Static cold storage (SCS), the current clinical gold standard for organ preservation, provides surgeons with a limited window of time between procurement and transplantation. In vascularized composite allotransplantation (VCA), this time limitation prevents many viable allografts from being designated to the best-matched recipients. Machine perfusion (MP) systems hold significant promise for extending and improving organ preservation. Most of the prior MP systems for VCA have been built and tested for large animal models. However, small animal models are beneficial for high-throughput biomolecular investigations. This study describes the design and development of a multiparametric bioreactor with a circuit customized to perfuse rat abdominal wall VCAs. To demonstrate its concept and functionality, this bioreactor system was employed in a small-scale demonstrative study in which biomolecular metrics pertaining to graft viability were evaluated non-invasively and in real time. We additionally report a low incidence of cell death from ischemic necrosis as well as minimal interstitial edema in machine perfused grafts. After up to 12 h of continuous perfusion, grafts were shown to survive transplantation and reperfusion, successfully integrating with recipient tissues and vasculature. Our multiparametric bioreactor system for rat abdominal wall VCA provides an advanced framework to test novel techniques to enhance normothermic and sub-normothermic VCA preservations in small animal models.

4.
Carbohydr Polym ; 332: 121948, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431386

RESUMO

Pickering emulsions stabilized by solid particles are more stable and environmentally friendly compared to traditional surfactants. Herein, a series of Chitosan-g-Poly(N-vinylcaprolactam) (CS-g-PNVCL) microgel particles were synthesized via a free radical surfactant-free emulsion copolymerization and the obtained particles were used to stabilize Pickering emulsions. It is found that the ratio (CS/PNVCL = 60 wt%) was optimal to produce Pickering emulsions. The microstructures of Pickering emulsions can maintain for 60 days at room temperature and this long-term stability is attributed to the CS-g-PNVCL microgel particles adsorbed at the oil-water interface. The Pickering emulsions displayed thermo-responsive characteristics when exposed to environmental stimuli. The emulsions became destabilized with an increase in pH and temperature. The droplets turned unstable and irregular due to excessive NaCl concentration, caused by electrostatic repulsion between the microgel particles. This study presents a novel way to form smart and uniform Pickering emulsions with the application potential in food, cosmetics, and drug delivery, etc.

5.
Nat Protoc ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514838

RESUMO

The synthesis of synthetic intracellular polymers offers groundbreaking possibilities in cellular biology and medical research, allowing for novel experiments in drug delivery, bioimaging and targeted cancer therapies. These macromolecules, composed of biocompatible monomers, are pivotal in manipulating cellular functions and pathways due to their bioavailability, cytocompatibility and distinct chemical properties. This protocol details two innovative methods for intracellular polymerization. The first one uses 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure 2959) as a photoinitiator for free radical polymerization under UV light (365 nm, 5 mW/cm2). The second method employs photoinduced electron transfer-reversible addition-fragmentation chain-transfer polymerization with visible light (470 nm, 100 mW/cm2). We further elaborate on isolating these intracellular polymers by streptavidin/biotin interaction or immobilized metal ion affinity chromatography for polymers tagged with biotin or histidine. The entire process, from polymerization to isolation, takes ~48 h. Moreover, the intracellular polymers thus generated demonstrate significant potential in enhancing actin polymerization, in bioimaging applications and as a novel avenue in cancer treatment strategies. The protocol extends to animal models, providing a comprehensive approach from cellular to systemic applications. Users are advised to have a basic understanding of organic synthesis and cell biology techniques.

6.
Biomacromolecules ; 25(3): 1671-1681, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38354397

RESUMO

Nanoparticles (NPs) containing light-responsive polymers and imaging agents show great promise for controlled drug delivery. However, most light-responsive NPs rely on short-wavelength excitation, resulting in poor tissue penetration and potential cytotoxicity. Moreover, excessively sensitive NPs may prematurely release drugs during storage and circulation, diminishing their efficacy and causing off-target toxicity. Herein, we report visible-light-responsive NPs composed of an amphiphilic block copolymer containing responsive 4-acrylamide benzenesulfonyl azide (ABSA) and hydrophilic N,N'-dimethylacrylamide (DMA) units. The polymer pDMA-ABSA was loaded with the chemotherapy drug dasatinib and zinc tetraphenylporphyrin (ZnTPP). ZnTPP acted as an imaging reagent and a photosensitizer to reduce ABSA upon visible light irradiation, converting hydrophobic units to hydrophilic units and disrupting NPs to trigger drug release. These NPs enabled real-time fluorescence imaging in cells and exhibited synergistic chemophotodynamic therapy against multiple cancer cell lines. Our light-responsive NP platform holds great promise for controlled drug delivery and cancer theranostics, circumventing the limitations of traditional photosensitive nanosystems.


Assuntos
Portadores de Fármacos , Metaloporfirinas , Nanopartículas , Portadores de Fármacos/química , Azidas , Polímeros/química , Luz , Nanopartículas/química , Liberação Controlada de Fármacos
7.
Neurosurg Rev ; 47(1): 38, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38196057

RESUMO

Different recanalization times for endovascular interventions may affect the success of non-acute internal carotid artery occlusion procedures. Nomograms can provide personalized and more accurate risk estimates based on predictive values. Therefore, we developed a nomogram to predict the probability of success of endovascular recanalization procedures for non-acute internal carotid artery occlusion. We performed a single-center retrospective analysis of data collected from patients who underwent endovascular treatment for non-acute internal carotid artery occlusion between January 2015 and December 2022. Multifactorial logistic regression analyses were performed to identify independent predictors affecting the success rate of non-acute internal carotid artery occlusion procedures and to create nomograms. The model was differentiated and calibrated using the area under the ROC curve (AUC-ROC) and calibration plots. Internal validation of the model was performed by using resampling (1000 replications). In total, 46 patients were identified and a total of 39 patients met the study criteria. Predictors in the nomogram included vascular occlusion proximal morphology, reversed flow of the ophthalmic artery, and recanalization time. The model showed good resolution with an ROC area of 0.917 (95% CI: 0.814-0.967). The nomogram can be used to personalize, visualize, and accurately predict the surgical success of endovascular treatment of non-acute internal carotid artery occlusion.


Assuntos
Doenças das Artérias Carótidas , Nomogramas , Humanos , Artéria Carótida Interna/cirurgia , Estudos Retrospectivos , China
8.
iScience ; 27(2): 108447, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38292422

RESUMO

Bladder cancer (BC) is a prevalent and deadly disease. circCD2AP was suggested to be highly expressed in BC. However, the exact mechanism needs further investigation. In this study, circCD2AP was observed to be upregulated in BC and linked to poor prognosis in individuals. Functionally, circCD2AP or USP21 knockdown inhibited BC cell EMT and stemness both in vitro and in vivo. Mechanistically, circCD2AP interacted with ELAVL1 to enhance the stability of USP21 mRNA, which, in turn, inhibited the ubiquitination degradation of FOXQ1. Through rescue assay, USP21 or FOXQ1 knockdown was found to abolish the promoting effects of circCD2AP or USP21 overexpression on BC cell EMT and stemness. Overall, this study has unveiled the role of circCD2AP/ELAVL1/USP21/FOXQ1 axis in BC EMT and stemness regulation, offering insights into the mechanisms underlying BC progression, with potential implications for therapeutic strategies.

9.
Insect Mol Biol ; 33(1): 41-54, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37740676

RESUMO

Caddisworms (Trichoptera) spin adhesive silks to construct a variety of underwater composite structures. Many studies have focused on the fibroin heavy chain of caddisworm silk and found that it contains heavy phosphorylation to maintain a stable secondary structure. Besides fibroins, recent studies have also identified some new silk proteins within caddisworm silk. To better understand the silk composition and its secretion process, this study reports the silk gland proteome of a retreat-building caddisworm, Stenopsyche angustata Martynov (Trichoptera, Stenopsychidae). Using liquid chromatography tandem mass spectrometry (LC-MS/MS), 2389 proteins were identified in the silk gland of S. angustata, among which 192 were predicted as secreted silk proteins. Twenty-nine proteins were found to be enriched in the front silk gland, whereas 109 proteins were enriched in the caudal silk gland. The fibroin heavy chain and nine uncharacterized silk proteins were identified as phosphorylated proteins. By analysing the sequence of the fibroin heavy chain, we found that it contains 13 Gly/Thr/Pro-rich regions, 12 Val/Ser/Arg-rich regions and a Gly/Arg/Thr-rich region. Three uncharacterized proteins were identified as sericin-like proteins due to their larger molecular weights, signal peptides and repetitive motifs rich in serine. This study provides valuable information for further clarifying the secretion and adhesion of underwater caddisworm silk.


Assuntos
Bombyx , Fibroínas , Animais , Seda/química , Fibroínas/genética , Fibroínas/química , Insetos/metabolismo , Larva/metabolismo , Proteoma/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Bombyx/metabolismo , Proteínas de Insetos/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 48(20): 5397-5403, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-38114133

RESUMO

Functional dyspepsia(FD) is a prevalent functional gastrointestinal disease characterized by recurrent and long-lasting symptoms that significantly impact the quality of life of patients. Currently, western medicine treatment has not made breakthrough progress and mainly relies on symptomatic therapies such as gastrointestinal motility agents, acid suppressants, antidepressants/anxiolytics, and psychotherapy. However, these treatments have limitations in terms of insufficient effectiveness and safety. Traditional Chinese medicine(TCM) possesses unique advantages in the treatment of FD. Through literature search in China and abroad, it has been found that the mechanisms of TCM in treating FD is associated with various signaling pathways, and research on these signaling pathways and molecular mechanisms has gradually become a focus. The main signaling pathways include the SCF/c-Kit signaling pathway, 5-HT signaling pathway, CRF signaling pathway, AMPK signaling pathway, TRPV1 signaling pathway, NF-κB signaling pathway, and RhoA/ROCK2/MYPT1 signaling pathway. This series of signaling pathways can promote gastrointestinal motility, alleviate anxiety, accelerate gastric emptying, reduce visceral hypersensitivity, and improve duodenal micro-inflammation in the treatment of FD. This article reviewed the research on TCM's regulation of relevant signaling pathways in the treatment of FD, offering references and support for further targeted TCM research in the treatment of FD.


Assuntos
Dispepsia , Humanos , Dispepsia/tratamento farmacológico , Dispepsia/genética , Medicina Tradicional Chinesa , Qualidade de Vida , Fármacos Gastrointestinais/uso terapêutico , Transdução de Sinais
11.
Arch Esp Urol ; 76(7): 481-486, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37867332

RESUMO

BACKGROUND: The 8th edition of the American Joint Committee on Cancer (AJCC) has made new revisions to the N staging of penile cancer (PeCa). This study aimed to evaluate the prognostic value of the new N staging classification. METHODS: This cohort was included from the Surveillance, Epidemiology, and End Results (SEER) database (1988-2016). Overall survival (OS) and cancer-specific survival (CSS) were evaluated using Kaplan-Meier survival curve. The Cox proportional hazards model was employed to calculate hazard ratio (HR) and 95% confidence intervals (CI). RESULTS: Among the included 583 patients, 270 patients had only one positive inguinal lymph node (ILNP), 115 had two ILNPs, and 198 had 3 or more ILNPs. Kaplan-Meier analysis indicated that The OS and CSS of patients with ILNP = 2 were not statistically different from those with ILNP = 1 (p = 0.394; p = 0.760), but had OS and CSS benefit over those with ILNP ≥3 (p = 0.017; p = 0.020). Cox proportional hazards regression analysis indicated that patients with ILNP = 2 and ILNP = 1 have similar OS and CSS (HR = 0.80, p = 0.153; HR = 0.74, p = 0.148), but patients with ILNP ≥3 had worse OS and CSS than patients with ILNP = 2 (HR = 1.56, p = 0.007; HR = 1.86, p = 0.003). CONCLUSIONS: PeCa patients with only one or two lymph node metastases had similar survival outcomes. AJCC 8th edition pN staging has a better discriminative ability to predict the prognosis and can accurately stratify mortality risk in PeCa.


Assuntos
Neoplasias Penianas , Masculino , Humanos , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estimativa de Kaplan-Meier
12.
Pharmaceutics ; 15(9)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37765191

RESUMO

Hyperbranched polymers are a class of three-dimensional dendritic polymers with highly branched architectures. Their unique structural features endow them with promising physical and chemical properties, such as abundant surface functional groups, intramolecular cavities, and low viscosity. Therefore, hyperbranched-polymer-constructed cargo delivery carriers have drawn increasing interest and are being utilized in many biomedical applications. When applied for photodynamic therapy, photosensitizers are encapsulated in or covalently incorporated into hyperbranched polymers to improve their solubility, stability, and targeting efficiency and promote the therapeutic efficacy. This review will focus on the state-of-the-art studies concerning recent progress in hyperbranched-polymer-fabricated phototherapeutic nanomaterials with emphases on the building-block structures, synthetic strategies, and their combination with the codelivered diagnostics and synergistic therapeutics. We expect to bring our demonstration to the field to increase the understanding of the structure-property relationships and promote the further development of advanced photodynamic-therapy nanosystems.

13.
Arch. esp. urol. (Ed. impr.) ; 76(7): 481-486, 28 sept. 2023. tab, graf
Artigo em Inglês | IBECS | ID: ibc-226425

RESUMO

Background: The 8th edition of the American Joint Committee on Cancer (AJCC) has made new revisions to the N staging of penile cancer (PeCa). This study aimed to evaluate the prognostic value of the new N staging classification. Methods: This cohort was included from the Surveillance, Epidemiology, and End Results (SEER) database (1988–2016). Overall survival (OS) and cancer-specific survival (CSS) were evaluated using Kaplan–Meier survival curve. The Cox proportional hazards model was employed to calculate hazard ratio (HR) and 95% confidence intervals (CI). Results: Among the included 583 patients, 270 patients had only one positive inguinal lymph node (ILNP), 115 had two ILNPs, and 198 had 3 or more ILNPs. Kaplan–Meier analysis indicated that The OS and CSS of patients with ILNP = 2 were not statistically different from those with ILNP = 1 (p = 0.394; p = 0.760), but had OS and CSS benefit over those with ILNP ≥3 (p = 0.017; p = 0.020). Cox proportional hazards regression analysis indicated that patients with ILNP = 2 and ILNP = 1 have similar OS and CSS (HR = 0.80, p = 0.153; HR = 0.74, p = 0.148), but patients with ILNP ≥3 had worse OS and CSS than patients with ILNP = 2 (HR = 1.56, p = 0.007; HR = 1.86, p = 0.003). Conclusions: PeCa patients with only one or two lymph node metastases had similar survival outcomes. AJCC 8th edition pN staging has a better discriminative ability to predict the prognosis and can accurately stratify mortality risk in PeCa (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Neoplasias Penianas/mortalidade , Estadiamento de Neoplasias , Estimativa de Kaplan-Meier , Estudos de Coortes , Prognóstico
14.
Biomater Sci ; 11(18): 6149-6159, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37548310

RESUMO

Controlled drug release of nanoparticles was achieved by irreversibly disrupting polymer micelles through high-intensity focused ultrasound (HIFU) induction. An ultrasound-responsive block copolymer was synthesized, comprising an end-functional Eosin Y fluorophore, 2-tetrahydropyranyl acrylate (THPA), and acrylate mannose (MAN). The block copolymer was then self-assembled to produce micelles. The chemotherapy drug dasatinib (DAS) and the sonodynamic therapy agent methylene blue (MB) were encapsulated by the self-assembly of the block copolymer. This targeted nanoparticle enables sonodynamic therapy through high-intensity focused ultrasound while triggering nanoparticle disassembly for controlled drug release. The ultrasound-mediated, non-invasive strategy provides external spatiotemporal control for targeted tumour treatment.


Assuntos
Micelas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Polímeros , Ultrassonografia , Liberação Controlada de Fármacos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
15.
Artigo em Inglês | MEDLINE | ID: mdl-37372752

RESUMO

Landscape paintings provide an abundant and objective representation of good and distinctive local scenery, which is widely used in local landscape analysis, so the comprehensive research of landscape paintings is fundamental and necessary for the subsequent landscape planning work. Landscape paintings include both planar information and spatial information. However, there has been little previous work on landscape paintings from both a three-dimensional and planar perspective, and the landscape features of landscape paintings have not yet been comprehensively clarified. Therefore, this paper, taking the Seto Inland Sea area as a case study, aims to comprehensively clarify the landscape features of the paintings and provide a valuable index of "good and characteristic landscapes" in this area based on the two planar features of element configuration and color, along with one spatial feature (element arrangement). To deeply clarify the typical landscape features of paintings, we attempt to propose a classification method by combining the similarity of features in different attributions. The results indicate that Sky, Green, and Sea are the most essential landscape elements, and yellow (orange), blue, and green hues are the most used in the paintings. In addition, the paintings were classified into eight typical landscapes, and seascape and field landscapes were the most significant presented in the landscape paintings in this area. This study presents a method to clarify the landscape features from both planar and spatial perspectives, providing more comprehensive guidance and data support for the subsequent landscape planning work and analysis-especially in regional landscape exploration-and for the development of tourism landscape resources in urban planning.

16.
Adv Colloid Interface Sci ; 313: 102861, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36842344

RESUMO

Dynamic wetting is a ubiquitous phenomenon and frequently observed in our daily life, as exemplified by the famous lotus effect. It is also an interfacial process of upmost importance involving many cutting-edge applications and has hence received significantly increasing academic and industrial attention for several decades. However, we are still far away to completely understand and predict wetting dynamics for a given system due to the complexity of this dynamic process. The physics of moving contact lines is mainly ascribed to the full coupling with the solid surface on which the liquids contact, the atmosphere surrounding the liquids, and the physico-chemical characteristics of the liquids involved (small-molecule liquids, metal liquids, polymer liquids, and simulated liquids). Therefore, to deepen the understanding and efficiently harness wetting dynamics, we propose to review the major advances in the available literature. After an introduction providing a concise and general background on dynamic wetting, the main theories are presented and critically compared. Next, the dynamic wetting of various liquids ranging from small-molecule liquids to simulated liquids are systematically summarized, in which the new physical concepts (such as surface segregation, contact line fluctuations, etc.) are particularly highlighted. Subsequently, the related emerging applications are briefly presented in this review. Finally, some tentative suggestions and challenges are proposed with the aim to guide future developments.

17.
Neurosurg Rev ; 46(1): 42, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36707467

RESUMO

The occurrence of bleeding events after stent-assisted embolization of a ruptured artery requiring continuous double antiplatelet therapy may seriously affect the prognosis of this group of patients. A nomogram can provide a personalized, more accurate risk estimate based on predictors. We, therefore, developed a nomogram to predict the probability of bleeding events in patients with stent-assisted ruptured aneurysm embolization. We performed a single-center retrospective analysis of data collected from patients undergoing stent-assisted ruptured aneurysm embolization between January 2018 and December 2021. Forward stepwise logistic regression was performed to identify independent predictors of adverse events of bleeding after stent-assisted embolization and to establish nomograms. Discrimination and calibration of this model were performed using the area under the ROC curve (AUC-ROC) and the calibration plot. The model is internally validated by using resampling (1000 replicates). A total of 131 patients were identified, and a total of 118 patients met the study criteria. The predictors included in the nomogram were body mass index (BMI), AAi, and MA-ADP. The model showed good resolving power with a ROC area of 0.893 (95% CI: 0.834 ~ 0.952) for this model with good calibration. The nomogram can be used to individualize, visualize, and accurately predict the risk probability of bleeding events after stent-assisted embolization of ruptured aneurysms.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , Humanos , Nomogramas , Estudos Retrospectivos , População do Leste Asiático , Alta do Paciente , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/etiologia , Resultado do Tratamento , Hemorragia/etiologia , Stents/efeitos adversos , Embolização Terapêutica/efeitos adversos , Aneurisma Roto/etiologia
18.
J Biomed Mater Res A ; 111(7): 938-949, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36585800

RESUMO

The use of therapeutic proteins and peptides is of great interest for the treatment of many diseases, and advances in nanotechnology offer a path toward their stable delivery via preferred routes of administration. In this study, we sought to design and formulate a nanostructured lipid carrier (NLC) containing a nominal antigen (insulin peptide) for oral delivery. We utilized the design of experiments (DOE) statistical method to determine the dependencies of formulation variables on physicochemical particle characteristics including particle size, polydispersity (PDI), melting point, and latent heat of melting. The particles were determined to be non-toxic in vitro, readily taken up by primary immune cells, and found to accumulate in regional lymph nodes following oral administration. We believe that this platform technology could be broadly useful for the treatment of autoimmune diseases by supporting the development of oral delivery-based antigen specific immunotherapies.


Assuntos
Portadores de Fármacos , Nanoestruturas , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Nanotecnologia , Administração Oral , Tamanho da Partícula
19.
Polymers (Basel) ; 16(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38201755

RESUMO

The nanocomposites with reversible cross-linking covalent bonds were prepared by reacting furfurylamine (FA)-modified diglycidyl ether of bisphenol A (DGEBA) and furfuryl-functionalized aniline trimer-modified graphene (TFAT-G) with bismaleimide (BMI) via the Diels-Alder (DA) reaction. The successful synthesis of the TFAT modifier is confirmed by nuclear magnetic resonance (NMR) hydrogen spectroscopy and IR spectroscopy tests. The structure and properties of TFAT-G epoxy nanocomposites are characterized by scanning electron microscopy (SEM), differential scanning calorimeter (DSC), tensile, and resistivity. The results show that TFAT-G was uniformly dispersed in the resin, and 1 wt% TFAT-G composites increased to 233% for tensile strength, 63% for elongation at break, 66% for modulus, and 7.8 °C for Tg. In addition, the addition of unmodified graphene degrades the mechanical properties of the composite. Overall, the graphene/self-healing resin nanocomposites have both good self-healing function and electrical conductivity by adding 1 wt% modified graphene; this allows for the maintenance of the original 83% strength and 89% electrical conductivity after one cycle of heating repair.

20.
Phys Rev Lett ; 129(21): 215901, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461959

RESUMO

High quality nanomechanical oscillators are promising platforms for quantum entanglement and quantum technology with phonons. Realizing coherent transfer of phonons between distant oscillators is a key challenge in phononic quantum information processing. Here, we report on the realization of robust unidirectional adiabatic pumping of phonons in a parametrically coupled nanomechanical system engineered as a one-dimensional phononic topological insulator. By exploiting three nearly degenerate local modes-two edge states and an interface state between them-and the dynamic modulation of their mutual couplings, we achieve nonreciprocal adiabatic transfer of phononic excitations from one edge to the other with near unit fidelity. We further demonstrate the robustness of such adiabatic transfer of phonons in the presence of various noises in the control signals. Our experiment paves the way toward nonreciprocal phonon dynamics via adiabatic pumping and is valuable for phononic quantum information processing.

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