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1.
Angew Chem Int Ed Engl ; 63(6): e202318792, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38117669

RESUMO

Electroreduction of nitric oxide (NO) to NH3 (NORR) has gained extensive attention for the sake of low carbon emission and air pollutant treatment. Unfortunately, NORR is greatly hindered by its sluggish kinetics, especially under low concentrations of NO. Herein, we developed a chlorine (Cl) vacancy strategy to overcome this limitation over FeOCl nanosheets (FeOCl-VCl ). Density functional theory (DFT) calculations revealed that the Cl vacancy resulted in defective Fe with sharp d-states characteristics in FeOCl-VCl to enhance the absorption and activation of NO. In situ X-ray absorption near-edge structure (XANES) and attenuated total reflection-infrared spectroscopy (ATR-IR) verified the lower average oxidation state of defective Fe to enhance the electron transfer for NO adsorption/activation and facilitate the generation of key NHO and NHx intermediates. As a result, the FeOCl-VCl exhibited superior NORR activities with the NH3 Faradaic efficiency up to 91.1 % while maintaining a high NH3 yield rate of 455.4 µg cm-2 h-1 under 1.0 vol % NO concentration, competitive with those of previously reported literatures under higher NO concentration. Further, the assembled Zn-NO battery utilizing FeOCl-VCl as cathode delivered a record peak power density of 6.2 mW cm-2 , offering a new route for simultaneous NO removal, NH3 production, and energy supply.

2.
Heliyon ; 9(11): e22514, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034610

RESUMO

As the presence of a percolating network formed by filler is indispensable for field grading composite, particulate fillers often result in high filler content that can be unfavorable in some aspects. The utilization of fillers with high aspect ratio is an effective way of reducing percolation threshold. In this work, Fe3O4 microplate (FMP) was prepared by a PVP-assisted hydrothermal method and it was adopted to fabricate composite films with different filler content by using polyetherimide (PEI) as the matrix. The composite film exhibited a percolation threshold of approximately 8 phr. The nonlinear coefficient measured 6.28 at a filler content of 10 phr. The nonlinearity in the conductive behavior of the composites was attributed to tunneling effect and Schottky emission. The filling of the FMP into PEI resulted in increase in dielectric constant and the dielectric loss maintained low. This study suggests that the FMP is a promising filler of low-filler-content field grading composite.

3.
ACS Appl Mater Interfaces ; 15(28): 34055-34063, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37410953

RESUMO

Ionic conductive eutectogels have great application prospects in wearable strain sensors owing to their temperature tolerance, simplicity, and low cost. Eutectogels prepared by cross-linking polymers have good tensile properties, strong self-healing capacities, and excellent surface-adaptive adhesion. Herein, we emphasize for the first time the potential of zwitterionic deep eutectic solvents (DESs), in which betaine is a hydrogen bond acceptor. Polymeric zwitterionic eutectogels were prepared by directly polymerizing acrylamide in zwitterionic DESs. The obtained eutectogels owned excellent ionic conductivity (0.23 mS cm-1), superior stretchability (approximately 1400% elongation), self-healing (82.01%), self-adhesion, and wide temperature tolerance. Accordingly, the zwitterionic eutectogel was successfully applied in wearable self-adhesive strain sensors, which can adhere to skins and monitor body motions with high sensitivity and excellent cyclic stability over a wide temperature range (-80 to 80 °C). Moreover, this strain sensor owned an appealing sensing function on bidirectional monitoring. The findings in this work can pave the way for the design of soft materials with versatility and environmental adaptation.

4.
Virol J ; 18(1): 51, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685499

RESUMO

BACKGROUND: Human papillomavirus (HPV) infection is currently the main cause of cervical cancer and precancerous lesions in female patients. By analyzing 6-year patient data from Shanghai Zhoupu Hospital in China, we retrospectively analyzed the epidemiological characteristics of women to determine the relationship between HPV genotype and cytological test results. METHODS: From 2014 to 2019, 23,724 cases of cervical shedding were collected from Zhoupu Hospital in Shanghai, China. By comparing the results of HPV and ThinPrep cytology test (TCT), the HPV infection rate of patients was retrospectively analyzed. HPV genotyping using commercial kits can detect 21 HPV subtypes (15 high-risk and 6 low-risk). According to the definition of the Bethesda system, seven types of cervical cytology results were involved. RESULTS: 3816 among 23,724 women, nearly 16.08%, were infected with HPV. The top three highest HPV prevalence rates were high-risk type infection, including HPV52 (3.19%), 58 (2.47%) and 16 (2.34%). The number of single-type HPV infections (3480 (91.20%)) was much larger than the number of multi-type ones (336 (8.8%)). Single-type infections were mainly in women aged 50-60 (16.63%) and women under 30 (15.37%), while multi-type infections were more common in women over 60 (2.67%). By analyzing the long-term trends, between 2014 and 2019, HPV52, 58, and 16 subtypes changed significantly, and the HPV positive rate also changed significantly during this period. Among 4502 TCT positive women, 15 (4.04%), 125 (2.64%),159 (1.54%), 4202 (17.71%) and 1 (0.004%) had atypical glandular cells (AGC), high-grade squamous intraepithelial lesions (HSIL), low-grade squamous intraepithelial lesions (LSIL), atypical squamous cells (ASC)and cervical adenocarcinoma, respectively. The HPV infection rates were 66.08%, 63.99%, 115.20%, 119.50%, and 31.72% for NILM, AGCs, HSILs LSILs and ASCs, respectively. CONCLUSIONS: HPV and TCT screening were very important steps in the secondary prevention of cervical cancer. Through the tracking and analysis of HPV and TCT results in this study, it can provide valuable information for Shanghai's HPV screening and prevention strategies, and provide references for clinical decision-making in the treatment of cervical cancer and precancerous lesions.


Assuntos
Infecções por Papillomavirus , Lesões Pré-Cancerosas , Lesões Intraepiteliais Escamosas , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Adulto , China/epidemiologia , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/virologia , Estudos Retrospectivos , Lesões Intraepiteliais Escamosas/epidemiologia , Lesões Intraepiteliais Escamosas/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia
5.
Biosens Bioelectron ; 86: 502-507, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27442080

RESUMO

MicroRNA (miRNA) plays a key regulatory role in many biological processes, emerging as an important biomarker for a large variety of cancer diseases. Employing gold nanoparticle (AuNP)-coated magnetic microbeads (AuNP-MMBs) as an immobilization matrix for higher loading density of hairpin-structured DNA probes and then ferrocene (Fc)-capped gold nanoparticle/streptavidin conjugates, amplified electrochemical assay of miRNA has been performed. In the presence of target miRNA, a novel assembly was formed via linking biotinylated hairpin DNA probe-covered AuNP-MMBs with Fc-capped gold nanoparticle/streptavidin conjugates and then collected by magnetic electrodes for voltammetric detection. The enlarged surface area, good conductivity of AuNP-MMBs and the multiple Fc tags on the electrode surface ensure high sensitivity of the method. The oxidation peak current of Fc tags is proportional to the concentrations of miRNA ranging from 5 fM to 100 fM, and a detection limit of 0.14 fM was achieved. The proposed assay is highly selective and reproducible, serving as a viable alternative for the detection of miRNA-182 from serum samples of glioma patients.


Assuntos
Técnicas Eletroquímicas/métodos , Compostos Ferrosos/química , Glioma/sangue , Ouro/química , MicroRNAs/sangue , Nanopartículas/química , Estreptavidina/química , Técnicas Biossensoriais/métodos , Sondas de DNA/química , Humanos , Limite de Detecção , Imãs/química , Metalocenos , MicroRNAs/análise , Nanopartículas/ultraestrutura
6.
Analyst ; 141(1): 331-6, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26613550

RESUMO

Oligomeric amyloid-beta (Aß) peptides are considered as the most toxic species in Alzheimer's disease (AD). Monitoring of the Aß aggregation profiles is critical for elucidating the oligomer toxicity and may serve as a therapeutic target for AD. By immobilizing the capture antibodies of A11 and OC that are specific to the oligomers and fibrils, respectively, in separate fluidic channels, a novel surface plasmon resonance (SPR) biosensor was designed for monitoring the oligomeric and fibrillar species of Aß(1-42) simultaneously. The influence of curcumin, Cu(2+) and methylene blue on the amount of toxic oligomers and fibrils was evaluated. The half maximal inhibitory concentration (IC50) of curcumin and methylene blue was determined. The formation of Aß fibrils was also validated by the thioflavin T (ThT) fluorescence assay. The results demonstrate the utility of SPR as an analytical tool for rapid and comprehensive monitoring of Aß aggregation and screening of Aß modulators.


Assuntos
Peptídeos beta-Amiloides/química , Avaliação Pré-Clínica de Medicamentos/métodos , Fragmentos de Peptídeos/química , Agregados Proteicos , Multimerização Proteica/efeitos dos fármacos , Ressonância de Plasmônio de Superfície/métodos , Curcumina/farmacologia , Azul de Metileno/farmacologia , Estrutura Quaternária de Proteína , Fatores de Tempo
7.
Org Lett ; 7(20): 4471-4, 2005 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-16178561

RESUMO

[reaction: see text] Directional intramolecular interactions play a critical role in the self-assembly of donor-sigma-acceptor molecules in solution. Amide functions on the periphery of the tricyclic core stabilize a C3-symmetric monomer conformation by intramolecular hydrogen bonding and dipole-dipole interactions. The molecules are effective organogelators and show long-range ordering in the bulk.

8.
Org Lett ; 7(3): 443-6, 2005 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-15673260

RESUMO

[structure: see text] 3,5,7-Tris(arylmethyl)-1-aza-adamantanetrione donor-sigma-acceptor compounds have been synthesized in four steps. Computational and (1)H NMR analyses rationalize the solubility, gelation, and conformational properties of the C3-symmetric molecules toward employing sigma-coupled donor-acceptor interactions in molecular self-assembly.

9.
Nature ; 419(6904): 284-7, 2002 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-12239563

RESUMO

Electroactive polymers (EAPs) can behave as actuators, changing their shape in response to electrical stimulation. EAPs that are controlled by external electric fields--referred to here as field-type EAPs--include ferroelectric polymers, electrostrictive polymers, dielectric elastomers and liquid crystal polymers. Field-type EAPs can exhibit fast response speeds, low hysteresis and strain levels far above those of traditional piezoelectric materials, with elastic energy densities even higher than those of piezoceramics. However, these polymers also require a high field (>70 V micro m(-1)) to generate such high elastic energy densities (>0.1 J cm(-3); refs 4, 5, 9, 10). Here we report a new class of all-organic field-type EAP composites, which can exhibit high elastic energy densities induced by an electric field of only 13 V micro m(-1). The composites are fabricated from an organic filler material possessing very high dielectric constant dispersed in an electrostrictive polymer matrix. The composites can exhibit high net dielectric constants while retaining the flexibility of the matrix. These all-organic actuators could find applications as artificial muscles, 'smart skins' for drag reduction, and in microfluidic systems for drug delivery.


Assuntos
Indóis/química , Compostos Organometálicos/química , Polímeros/química , Órgãos Artificiais , Sistemas de Liberação de Medicamentos/métodos , Elasticidade , Condutividade Elétrica , Estimulação Elétrica , Tamanho da Partícula , Temperatura
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