Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Nature ; 591(7849): 240-245, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33692559

RESUMEN

Displays are basic building blocks of modern electronics1,2. Integrating displays into textiles offers exciting opportunities for smart electronic textiles-the ultimate goal of wearable technology, poised to change the way in which we interact with electronic devices3-6. Display textiles serve to bridge human-machine interactions7-9, offering, for instance, a real-time communication tool for individuals with voice or speech difficulties. Electronic textiles capable of communicating10, sensing11,12 and supplying electricity13,14 have been reported previously. However, textiles with functional, large-area displays have not yet been achieved, because it is challenging to obtain small illuminating units that are both durable and easy to assemble over a wide area. Here we report a 6-metre-long, 25-centimetre-wide display textile containing 5 × 105 electroluminescent units spaced approximately 800 micrometres apart. Weaving conductive weft and luminescent warp fibres forms micrometre-scale electroluminescent units at the weft-warp contact points. The brightness between electroluminescent units deviates by less than 8 per cent and remains stable even when the textile is bent, stretched or pressed. Our display textile is flexible and breathable and withstands repeated machine-washing, making it suitable for practical applications. We show that an integrated textile system consisting of display, keyboard and power supply can serve as a communication tool, demonstrating the system's potential within the 'internet of things' in various areas, including healthcare. Our approach unifies the fabrication and function of electronic devices with textiles, and we expect that woven-fibre materials will shape the next generation of electronics.


Asunto(s)
Terminales de Computador , Electrónica/instrumentación , Textiles , Humanos , Docilidad , Dispositivos Electrónicos Vestibles
2.
Trends Immunol ; 44(12): 1031-1045, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37932176

RESUMEN

Tumor immunotherapy is refashioning traditional treatments in the clinic for certain tumors, especially by relying on the activation of T cells. However, the safety and effectiveness of many antitumor immunotherapeutic agents are suboptimal due to difficulties encountered in assessing T cell responses and adjusting treatment regimens accordingly. Here, we review advances in the clinical visualization of T cell activity in vivo, and focus particularly on molecular imaging probes and biomarkers of T cell activation. Current challenges and prospects are also discussed that aim to achieve a better strategy for real-time monitoring of T cell activity, predicting prognoses and responses to tumor immunotherapy, and assessing disease management.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Linfocitos T , Neoplasias/terapia , Inmunoterapia/métodos , Imagen Molecular
3.
BMC Infect Dis ; 24(1): 595, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886649

RESUMEN

BACKGROUND AND PURPOSE: The persistent progression of pneumonia is a critical determinant of adverse outcomes in patients afflicted with COVID-19. This study aimed to predict personalized COVID-19 pneumonia progression between the duration of two weeks and 1 month after admission by integrating radiological and clinical features. METHODS: A retrospective analysis, approved by the Institutional Review Board, encompassed patients diagnosed with COVID-19 pneumonia between December 2022 and February 2023. The cohort was divided into training and validation groups in a 7:3 ratio. A trained multi-task U-Net network was deployed to segment COVID-19 pneumonia and lung regions in CT images, from which quantitative features were extracted. The eXtreme Gradient Boosting (XGBoost) algorithm was employed to construct a radiological model. A clinical model was constructed by LASSO method and stepwise regression analysis, followed by the subsequent construction of the combined model. Model performance was assessed using ROC and decision curve analysis (DCA), while Shapley's Additive interpretation (SHAP) illustrated the importance of CT features. RESULTS: A total of 214 patients were recruited in our study. Four clinical characteristics and four CT features were identified as pivotal components for constructing the clinical and radiological models. The final four clinical characteristics were incorporated as well as the RS_radiological model to construct the combined prediction model. SHAP analysis revealed that CT score difference exerted the most significant influence on the predictive performance of the radiological model. The training group's radiological, clinical, and combined models exhibited AUC values of 0.89, 0.72, and 0.92, respectively. Correspondingly, in the validation group, these values were observed to be 0.75, 0.72, and 0.81. The DCA curve showed that the combined model exhibited greater clinical utility than the clinical or radiological models. CONCLUSION: Our novel combined model, fusing quantitative CT features with clinical characteristics, demonstrated effective prediction of COVID-19 pneumonia progression from 2 weeks to 1 month after admission. This comprehensive model can potentially serve as a valuable tool for clinicians to develop personalized treatment strategies and improve patient outcomes.


Asunto(s)
Inteligencia Artificial , COVID-19 , Progresión de la Enfermedad , SARS-CoV-2 , Tomografía Computarizada por Rayos X , Humanos , COVID-19/diagnóstico por imagen , COVID-19/epidemiología , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Pulmón/diagnóstico por imagen , Pulmón/patología , Anciano , Adulto
4.
Chemistry ; 29(39): e202301157, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37156726

RESUMEN

In recent years, the strategy of merging visible light photocatalysis and organocatalysis has been utilized and applied in a wide range of reactions. Taking advantage of synergistic visible light photocatalysis with organocatalysis, remarkable progress has recently been achieved in modern chemical synthesis. In these dual catalytic systems, photocatalysts or photosensitizers absorb visible light to induce their photo-excited states which can activate unreactive substrates via electron or energy transfer mechanisms, and organocatalysts are usually employed to control the chemical reactivities of the other substrates. This review mainly focuses on the recent development of cooperative catalysis by the combination of organocatalysis and photocatalysis in recent organic synthesis.

5.
Ann Bot ; 131(5): 867-883, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36976653

RESUMEN

BACKGROUND AND AIMS: Artemisia is a mega-diverse genus consisting of ~400 species. Despite its medicinal importance and ecological significance, a well-resolved phylogeny for global Artemisia, a natural generic delimitation and infrageneric taxonomy remain missing, owing to the obstructions from limited taxon sampling and insufficient information on DNA markers. Its morphological characters, such as capitulum, life form and leaf, show marked variations and are widely used in its infrageneric taxonomy. However, their evolution within Artemisia is poorly understood. Here, we aimed to reconstruct a well-resolved phylogeny for global Artemisia via a phylogenomic approach, to infer the evolutionary patterns of its key morphological characters and to update its circumscription and infrageneric taxonomy. METHODS: We sampled 228 species (258 samples) of Artemisia and its allies from both fresh and herbarium collections, covering all the subgenera and its main geographical areas, and conducted a phylogenomic analysis based on nuclear single nucleotide polymorphisms (SNPs) obtained from genome skimming data. Based on the phylogenetic framework, we inferred the possible evolutionary patterns of six key morphological characters widely used in its previous taxonomy. KEY RESULTS: The genus Kaschgaria was revealed to be nested in Artemisia with strong support. A well-resolved phylogeny of Artemisia consisting of eight highly supported clades was recovered, two of which were identified for the first time. Most of the previously recognized subgenera were not supported as monophyletic. Evolutionary inferences based on the six morphological characters showed that different states of these characters originated independently more than once. CONCLUSIONS: The circumscription of Artemisia is enlarged to include the genus Kaschgaria. The morphological characters traditionally used for the infrageneric taxonomy of Artemisia do not match the new phylogenetic tree. They experienced a more complex evolutionary history than previously thought. We propose a revised infrageneric taxonomy of the newly circumscribed Artemisia, with eight recognized subgenera to accommodate the new results.


Asunto(s)
Artemisia , Filogenia , Artemisia/genética , Hojas de la Planta , Núcleo Celular
6.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-36232464

RESUMEN

The intestinal barrier is vital for preventing inflammatory bowel disease (IBD). The objectives of this study were to assess whether the Lactobacillus rhamnosus CY12 could alleviate oxidative stress, inflammation, and the disruption of tight junction (TJ) barrier functions induced by lipopolysaccharide (LPS), and therefore to explore the potential underlying molecular mechanisms. Our results showed that LPS-induced Cancer coli-2 (Caco-2) cells significantly increased the levels of reactive oxygen species (ROS), lactate dehydrogenase, inflammatory cytokines interleukin-1ß, interleukin-6, interleukin-8, and tumor necrosis factor-α (IL-1ß, IL-6, IL-8, and TNF-α), and the cell apoptosis rate while decreasing the levels of TJ proteins occludin, zonula occludens-1 (ZO-1), and claudin and antioxidant enzymes, such as catalase, superoxide dismutase, and glutathione peroxidase(CAT, SOD, and GSH-Px) (p < 0.05). However, Lactobacillus rhamnosus CY12 could relieve cytotoxicity, apoptosis, oxidative stress, and pro-inflammatory cytokine expressions, and also inhibit the Toll-like receptor 4/nuclear factor kappa-B(TLR4/NF-κB) signaling pathway. Furthermore, the gene expression of antioxidant enzymes, as well as the mRNA and protein expressions of TJ proteins, was improved. Particularly, the concentration of 108 cfu/mL significantly prevented the inflammatory injury induced by LPS in Caco-2 cells (p < 0.05). These findings support a potential application of Lactobacillus rhamnosus CY12 as a probiotic to prevent LPS-induced intestinal injury and treat intestinal barrier dysfunction.


Asunto(s)
Lacticaseibacillus rhamnosus , Proteínas de Uniones Estrechas , Antioxidantes/metabolismo , Antioxidantes/farmacología , Células CACO-2 , Catalasa/metabolismo , Claudinas/metabolismo , Glutatión Peroxidasa/metabolismo , Humanos , Inflamación , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Lactato Deshidrogenasas/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , Ocludina/genética , Ocludina/metabolismo , Estrés Oxidativo , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno , Superóxido Dismutasa/metabolismo , Proteínas de Uniones Estrechas/metabolismo , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
7.
Chem Rec ; 19(8): 1753-1767, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30946533

RESUMEN

Metal-containing nanomaterials have attracted widespread attention in recent years due to their physicochemical, light-scattering and plasmonic properties. By introducing different kinds and different structures of metal-containing nanomaterials into organic light-emitting diodes (OLEDs), the optical properties of the devices can be tailored, which can effectively improve the luminous efficiency of OLEDs. In this review, the fundamental knowledge of OLEDs and metallic nanomaterials were firstly introduced. Then we overviewed the recent development of the optimization of OLEDs through introducing different kinds of metal-containing nanomaterials.

8.
Sci Rep ; 14(1): 10337, 2024 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710802

RESUMEN

Infectious diseases have long been a shaping force in human history, necessitating a comprehensive understanding of their dynamics. This study introduces a co-evolution model that integrates both epidemiological and evolutionary dynamics. Utilizing a system of differential equations, the model represents the interactions among susceptible, infected, and recovered populations for both ancestral and evolved viral strains. Methodologically rigorous, the model's existence and uniqueness have been verified, and it accommodates both deterministic and stochastic cases. A myriad of graphical techniques have been employed to elucidate the model's dynamics. Beyond its theoretical contributions, this model serves as a critical instrument for public health strategy, particularly predicting future outbreaks in scenarios where viral mutations compromise existing interventions.


Asunto(s)
Procesos Estocásticos , Humanos , Sistema Inmunológico/virología , Evolución Molecular , Virus/genética , Virus/inmunología , Evolución Biológica
9.
Biomater Sci ; 12(3): 596-620, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38054499

RESUMEN

Antibiotic resistance is a growing problem that requires alternative antibacterial agents. MoS2, a two-dimensional transition metal sulfide, has gained significant attention in recent years due to its exceptional photocatalytic performance, excellent infrared photothermal effect, and impressive antibacterial properties. This review presents a detailed analysis of the antibacterial strategies and mechanism of MoS2, starting with its morphology and synthesis methods and focusing on the different interaction stages between MoS2 and bacteria. The paper summarizes the main antibacterial mechanisms of MoS2, such as photocatalytic antibacterial, enzyme-like catalytic antibacterial, physical antibacterial, and photothermal-assisted antibacterial. It offers a comprehensive discussion focus on recent research studies of photocatalytic antibacterial mechanisms and categorizes them, guiding the application of MoS2 in the antibacterial field. Overall, the review provides an in-depth understanding of the antibacterial mechanisms of MoS2 and presents the challenges and future directions for the improvement of MoS2 in the field of high-efficiency antibacterial materials.


Asunto(s)
Antibacterianos , Molibdeno , Molibdeno/farmacología , Antibacterianos/farmacología , Catálisis , Sulfuros
10.
ACS Nano ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38975713

RESUMEN

Tumor in situ vaccination (ISV) strategies have emerged in clinical trials as promising approaches, involving the release of tumor antigens through local radiotherapy and intratumorally adjuvant injections. However, the current fabrication strategy for achieving a sustainable immune response to ISV remains a pressing challenge. In this study, we present an empowered sustainable ISV method for antitumor therapy using 177Lu-labeled manganese-doped mesoporous hydroxyapatite (177Lu/Mn-HAP) microspheres. The ISV enables the sustained utilization of tumor antigens, leading to the activation of dendritic cells and polarization of macrophages toward the M1 subtype. Consequently, it facilitates the generation of potent CD8+ T-cell responses, enhancing the antitumor effects of internal radiation in both primary and distant tumors. Importantly, this approach achieves complete remission in all tumor-bearing mice and stimulates immune memory to prevent tumor recurrence. Our study highlights a universal and safe ISV strategy capable of inducing potent tumor-specific and sustainable immune response.

11.
BMJ Open ; 14(1): e082403, 2024 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267249

RESUMEN

INTRODUCTION: Upper limb and core strength training is essential for older adults to safely perform daily activities. However, existing exercise programmes mainly focus on lower limb strength and are not designed or delivered to suit people with different functional capacities. This study describes the design of a two-arm cluster randomised controlled trial to examine the effects of a multicomponent physical activity (PA) programme, Mobility-Fit, on mobility and frailty in older adults living in care facilities. METHODS AND ANALYSIS: 160 older adults from 20 care facilities in Hong Kong will be recruited and randomised by care facilities (1:1) to an intervention or a control group. Participants in the intervention group will attend the Mobility-Fit programme, led by facility-based instructors, three times per week, 45 min per session, for 12 weeks, while the control group will participate in a standard care lower limb strengthening programme offered by the care facility. Participants will then be followed up for 9 months. Mobility-Fit comprises agility, postural coordination, balance and strength training, with suitable dosage based on participant's baseline physical and cognitive function. The primary outcomes encompass upper and lower limb strength, trunk stability, reaction time, mobility function and fall efficacy. Secondary outcomes comprise daily PA level and performance, frailty, cognitive function and quality of life. A repeated measures analysis of variance (ANOVA) and generalised estimating equation (GEE) will be used to examine changes in outcomes over time and between groups. Data will be analysed following the intention-to-treat principles. We will also evaluate programme implementation and health economics throughout the follow-up period. ETHICS AND DISSEMINATION: Ethical approval was acquired in November 2022 from the Joint CUHK-NTEC Clinical Research Ethics Committee in Hong Kong (CREC-2022-459). Informed consent will be obtained from participants. The results of the study will be disseminated through peer-reviewed articles, conference presentations and social media. TRIAL REGISTRATION NUMBER: ChiCTR2300072709.


Asunto(s)
Fragilidad , Humanos , Anciano , Calidad de Vida , Análisis de Varianza , Ejercicio Físico , Extremidad Inferior , Ensayos Clínicos Controlados Aleatorios como Asunto
12.
Chemosphere ; 324: 138356, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36898437

RESUMEN

Decreasing bioaccessible antibiotics, heavy metals, and antibiotic resistance genes (ARGs) in soil by adsorption is an attractive, but unrealized, approach for ARG risk reduction. This approach has the potential to reduce the (co)selection pressure from antibiotics and heavy metals on bacteria and ARG horizontal gene transformation to pathogens. Here, a wet-state silicon-rich biochar/ferrihydrite composite (SiC-Fe(W)) synthesized by loading ferrihydrite onto rice straw-derived biochar was examined for i) adsorption of oxytetracycline and Cu2+ to reduce (co)selection pressure and ii) adsorption of extracellular antibiotic resistance plasmid pBR322 (containing tetA and blaTEM-1) to inhibit ARG transformation. SiC-Fe(W) gained the adsorption priority of biochar (for Cu2+) and wet-state ferrihydrite (for oxytetracycline and pBR322) and showed adsorptive enhancement (for Cu2+ and oxytetracycline) from a more wrinkled and exposed surface from biochar silica-dispersed ferrihydrite and a more negatively charged biochar, and the adsorption capacity for SiC-Fe(W) was 17-135 times that of soil. Correspondingly, 10 g/kg SiC-Fe(W) amendment increased the soil adsorption coefficient Kd by 31%-1417% and reduced the selection pressure from dissolved oxytetracycline, co-selection pressure from dissolved Cu2+, and transformation frequency of pBR322 (assessed with Escherichia coli). The development of Fe-O-Si bonds on silicon-rich biochar in alkaline enhanced ferrihydrite stability and adsorption capacity (for oxytetracycline), presenting a new potential strategy of biochar/ferrihydrite composite synthesis for adsorptive inhibition of ARG proliferation and transformation in ARG pollution control.


Asunto(s)
Metales Pesados , Oxitetraciclina , Contaminantes del Suelo , Antibacterianos/farmacología , Silicio/farmacología , Adsorción , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Carbón Orgánico/farmacología , Carbón Orgánico/química , Suelo/química , Farmacorresistencia Microbiana/genética , Proliferación Celular
13.
Sci Total Environ ; 875: 162652, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36894094

RESUMEN

The char component of biochar can act as an electron shuttle and redox agent to accelerate the transformation of ferrihydrite, but how the silicon component of biochar affects ferrihydrite transformation and pollutant removal remains unclear. In this paper, infrared spectroscopy, electron microscopy, transformation experiments and batch sorption experiments were conducted to examine a 2-line ferrihydrite formed by alkaline precipitation of Fe3+ on a rice straw-derived biochar. Fe-O-Si bonds were developed between the precipitated ferrihydrite particles and biochar silicon component, increasing mesopore volume (for mesopores with diameters of 10-100 nm) and surface area of ferrihydrite as the Fe-O-Si formation probably alleviated the aggregation of ferrihydrite particles. The Fe-O-Si bonding-contributed interactions blocked the transformation to goethite for ferrihydrite precipitated on biochar in a 30-day ageing and a 5-day Fe2+ catalysis ageing. Moreover, there was an increase of oxytetracycline adsorption capacity onto ferrihydrite-loaded biochar, which reached amazingly 3460 mg/g at the maximum, due to the Fe-O-Si bonding-contributed increase of surface area and oxytetracycline coordination sites. Ferrihydrite-loaded biochar as a soil amendment enhanced oxytetracycline adsorption and reduced the bacterial toxicity of dissolved oxytetracycline better than ferrihydrite did. These results provide new perspectives for the role of biochar (especially its silicon component) as an iron-based material carrier and a soil additive in the environmental effects of iron (hydr) oxides in water and soil.


Asunto(s)
Oxitetraciclina , Silicio , Adsorción , Compuestos Férricos/química , Hierro/química , Carbón Orgánico/química , Suelo
14.
ACS Appl Mater Interfaces ; 15(19): 23371-23379, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37155833

RESUMEN

Memristive devices, regardless of their potential applications in memory and computing scenarios, still suffer from large cycle-to-cycle and device-to-device variations due to the stochastic growth of conductive filaments (CFs). In this work, we fabricated a crossbar memristor using the 2D TiSe2 material and then oxidized it into TiO2 in the atmosphere at a moderate temperature. Such a mild oxidation approach fails to evaporate all Se into the air, and after further annealing using thermal or electrical stimulations, the remnant Se atoms gather near the interfaces and grow into nanosized crystals with relatively high conductivity. The resulting peninsula-shaped nanocrystals distort the electric field, forcing CFs to grow on them, which could largely confine the location and length of CFs. As a result, this two-terminal TiSe2/TiO2/TiSe2 device exhibits excellent resistive switching performance with a fairly low threshold voltage (Vset < 0.8 V, Vreset > 0.55 V) and high cycle-to-cycle consistency, enabling resistive switching at narrow operating variations, e.g., 500 ± 48 and 845 ± 39 mV. Our work offers a new approach to minimize the cycle-to-cycle stochasticity of the memristive device, paving the way for its applications in data storage and brain-inspired computing.

15.
Biol Direct ; 18(1): 58, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710294

RESUMEN

M7G modification, known as one of the common post-transcriptional modifications of RNA, is present in many different types of RNAs. With the accurate identification of m7G modifications within RNAs, their functional roles in the regulation of gene expression and different physiological functions have been revealed. In addition, there is growing evidence that m7G modifications are crucial in the emergence of cancer. Here, we review the most recent findings regarding the detection techniques, distribution, biological functions and Regulators of m7G. We also summarize the connections between m7G modifications and cancer development, drug resistance, and tumor microenvironment as well as we discuss the research's future directions and trends.


Asunto(s)
Neoplasias , Humanos , Neoplasias/genética , ARN/genética , Microambiente Tumoral/genética
16.
Infect Drug Resist ; 16: 2727-2735, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37168514

RESUMEN

Purpose: This study aimed to investigate the prevalence and genetic characterization of Serratia marcescens isolates from clinical bovine mastitis in Ningxia Hui Autonomous Region of China. Methods: S. marcescens was identified by the polymerase-chain reaction of 16S rRNA gene and sequencing. Antimicrobial susceptibility was tested by the disk diffusion method. Genes of resistance and virulence were determined by the PCR. Results: Overall, S. marcescens were confirmed from 32 of 2897 (1.1%) mastitis milk samples. These isolates showed high resistance to cefazolin (30/32, 93.8%) and chloramphenicol (28/32, 87.5%). A 12.5% (4/32) of the isolates displayed multidrug resistance (MDR). The most prevalent resistant genes found in S. marcescens were TEM (32/32, 100%) and CTX-M (24/32, 75.0%; CTX-M-15, 14/32, 43.8%; CTX-M-14, 8/32, 25.0%; CTX-M-65, 2/32, 6.3%) for extended-spectrum beta-lactamase, cmlA (28/32, 87.5%) and floR (16/32, 50.0%) for chloramphenicol resistance, SIM-1 (2/32, 6.3%) for carbapenemases, and sdeB (28/32, 87.5%), sdeY (26/32, 81.3%), sdeR (26/32, 81.3%) and sdeD (20/32, 62.5%) for efflux pumps. Moreover, all isolates carried virulence genes flhD, entB, and kpn, and most of them contained mrkD (30/32, 93.8%), ycfM (26/32, 81.3%), bsmB (26/32, 81.3%), pigP (26/32, 81.3%), kfu (24/32, 75.0%) and shlB (24/32, 75.0%). Conclusion: To our knowledge, this is the first report of genetic determinants for antimicrobial resistance and virulence in S. marcescens isolated from bovine mastitis cases in China. These findings are useful for developing strategies for prevention and treatment of bovine mastitis caused by S. marcescens in China.

17.
Int J Biol Macromol ; 253(Pt 5): 127222, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37797846

RESUMEN

The rapid development of modern electrical engineering puts forward urgent demand for high-performance electrical insulating materials. In this study, inspired by the layered structure of natural nacre, we present a novel biomimetic composite insulating film (referred to as M/C film) that is derived from agricultural waste corncobs and industrial waste mica tailings through a sol-gel-film transformation process. The novel insulating film has excellent tensile strength (94 MPa), high dielectric strength (68 kV mm-1), low dielectric loss, good heat resistance (T0 = 235 °C), and excellent UV shielding properties. Meanwhile, the M/C film presents environmental impacts much lower than those petrochemical-based plastic film as it can be 100 % recycled in a closed-loop recycling process and easily biodegraded in the environment (lignocellulose goes back to the carbon cycle and the mica return to the geological cycle). It is a potential alternative for petrochemical plastics and provides a possible way to utilize agricultural waste and mica tailings.


Asunto(s)
Silicatos de Aluminio , Lignina , Resistencia a la Tracción
18.
Biomater Sci ; 11(8): 2898-2911, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36883448

RESUMEN

Since nanozymes were proposed, their applications have become more and more extensive. As a research hotspot in recent years, MoS2 also shows many enzyme-like properties. However, as a novel peroxidase, MoS2 has the disadvantage of a low maximum reaction rate. In this study, the MoS2/PDA@Cu nanozyme was synthesized by a wet chemical method. The modification of PDA on the surface of MoS2 achieved the uniform growth of small-sized Cu Nps. The obtained MoS2/PDA@Cu nanozyme displayed excellent peroxidase-like activity and antibacterial properties. The minimum inhibitory concentration (MIC) of the MoS2/PDA@Cu nanozyme against S. aureus reached 25 µg mL-1. Furthermore, it showed a more pronounced inhibitory effect on bacterial growth with the addition of H2O2. The maximum reaction rate (Vmax) of the MoS2/PDA@Cu nanozyme is 29.33 × 10-8 M s-1, which is significantly higher as compared to that of HRP. It also exhibited excellent biocompatibility, hemocompatibility and potential anticancer properties. When the concentration of the nanozyme was 160 µg mL-1, the viabilities of 4T1 cells and Hep G2 cells were 45.07% and 32.35%, respectively. This work indicates that surface regulation and electronic transmission control are good strategies for improving peroxidase-like activity.


Asunto(s)
Molibdeno , Peroxidasa , Molibdeno/química , Staphylococcus aureus , Peróxido de Hidrógeno/farmacología , Peroxidasas/farmacología , Colorantes/farmacología , Antibacterianos/química
19.
Front Chem ; 10: 855352, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35308786

RESUMEN

Waterborne polyurethane has been proven to be an ideal additive for the preparation of hydrogels with excellent mechanical properties. This work reports that a satisfactory adhesion of acrylamide hydrogels can be obtained by introducing a large amount of waterborne polyurethane into system. A series of polyurethane hydrogels was prepared by using one-pot method with acrylamide monomer and 2-hydroxymethyl methacrylate end-modified waterborne polyurethane emulsion. The hydrogels exhibit good strength (greater than 30 KPa), wide range of adjustable strain (200%-800%), and excellent compression fatigue resistance. The performance improvement is attributed to the fact that the polyurethane emulsion containing double bonds provides chemical crosslinking and forms polyurethane microregions due to hydrophilic and hydrophobic interactions. The hydrogel shows extensive and repeatable adhesion on diverse substrates. This simple preparation method through polyurethane crosslinked hydrogels is expected to become a low-cost and efficient preparation strategy for hydrogel adhesives.

20.
Infect Drug Resist ; 15: 7363-7367, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36540100

RESUMEN

This study aimed to investigate the effects of ascorbic acid on antibiotic susceptibility of major bovine mastitis pathogens, including Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus uberis, Streptococcus agalactiae, and Escherichia coli. Minimum inhibitory concentrations (MICs) were determined by E-test method. The presence of 10 mM ascorbic acid decreased the MICs of penicillin and ampicillin while increased the MICs of erythromycin, kanamycin, streptomycin, and ciprofloxacin for all tested strains. Besides, ascorbic acid specifically reduced the MICs of tetracycline for gram-positive bacteria and chloramphenicol for gram-negative bacteria. This study highlights that ascorbic acid is a potential modulator of antibiotic activity against the major bovine mastitis pathogens.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA