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1.
Angew Chem Int Ed Engl ; 63(22): e202403739, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38565430

RESUMO

Deep-blue perovskite light-emitting diodes (PeLEDs) based on quasi-two-dimensional (quasi-2D) systems exist heightened sensitivity to the domain distribution. The top-down crystallization mode will lead to a vertical gradient distribution of quantum well (QW) structure, which is unfavorable for deep-blue emission. Herein, a thermal gradient annealing treatment is proposed to address the polydispersity issue of vertical QWs in quasi-2D perovskites. The formation of large-n domains at the upper interface of the perovskite film can be effectively inhibited by introducing a low-temperature source in the annealing process. Combined with the utilization of NaBr to inhibit the undesirable n=1 domain, a vertically concentrated QW structure is ultimately attained. As a result, the fabricated device delivers a narrow and stable deep-blue emission at 458 nm with an impressive external quantum efficiency (EQE) of 5.82 %. Green and sky-blue PeLEDs with remarkable EQE of 21.83 % and 17.51 % are also successfully achieved, respectively, by using the same strategy. The findings provide a universal strategy across the entire quasi-2D perovskites, paving the way for future practical application of PeLEDs.

2.
ACS Nano ; 18(8): 6513-6522, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38345358

RESUMO

The performance of blue perovskite light-emitting diodes (PeLEDs) lags behind the green and red counterparts owing to high trap density and undesirable red shift of the electroluminescence spectrum under operation conditions. Organic molecular additives were employed as passivators in previous reports. However, most commonly have limited functions, making it challenging to effectively address both efficiency and stability issues simultaneously. Herein, we reported an innovatively dynamic in situ hydrolysis strategy to modulate quasi-2D sky-blue perovskites by the multifunctional passivator phenyl dichlorophosphate that not only passivated the defects but also underwent in situ hydrolysis reaction to stabilize the emission. Moreover, hydrolysis products were beneficial for low-dimensional phase manipulation. Eventually, we obtained high-performance sky-blue PeLEDs with a maximum external quantum efficiency (EQE) of 16.32% and an exceptional luminance of 5740 cd m-2. More importantly, the emission peak of devices located at 485 nm remained stable under different biases. Our work signified the significant advancement toward realizing future applications of PeLEDs.

3.
Inquiry ; 60: 469580231220180, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38140825

RESUMO

Based on the complex aging background, more and more older people have to live in an institution in later life in China. The prevalence of cognitive frailty (CF) is more higher in institutions than in communities. Rarely studies were conducted on the relationship between institutional residence and CF. Hence, this study were performed to determine the relationship between institutional residence (living in a nursing home) and CF in older adults. A total of 1004 older community residents and 111 older nursing home residents over 50 years of age from Hefei, Anhui Province, China were recruited. CF included physical frailty (PF) and mild cognitive impairment (MCI). PF was assessed using the Chinese version of the Fried frailty scale, MCI was assessed using the Montreal Cognitive Assessment, and the common associated factors including sedentary behavior, exercise, intellectual activity, comorbidity, medication, chronic pain, sleep disorders, nutritional status and loneliness were analyzed using regression logistic models. Multivariate regression logistic analysis showed that exercise (P = .019, odds ratio [OR] = 0.494, 95% confidence interval [CI]: 0.274-0.891), intellectual activity (P = .019, OR = 0.595, 95% CI: 0.380-0.932), medication use (P = .003, OR = 2.388, 95% CI: 1.339-4.258), chronic pain (P = .003, OR = 1.580, 95% CI: 1.013-2.465) and loneliness (P = .000, OR = 2.991, 95% CI: 1.728-5.175) were significantly associated with CF in community residents; however, only sedentary behavior (P = .013, OR = 3.851, 95% CI: 1.328-11.170) was significantly associated with CF in nursing home residents. Our findings suggest that nursing homes can effectively address many common risk factors for CF, including lack of exercise and intellectual activity, medication use, chronic pain, and loneliness, better than the community setting. Thus, residing in a nursing home is conducive to the intervention of CF.


Assuntos
Dor Crônica , Disfunção Cognitiva , Fragilidade , Humanos , Pessoa de Meia-Idade , Idoso , Fragilidade/epidemiologia , Fragilidade/psicologia , Estudos Transversais , Disfunção Cognitiva/epidemiologia , Cognição
4.
Anal Chim Acta ; 1271: 341460, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37328245

RESUMO

Surface plasmon coupled emission (SPCE), a novel surface-enhanced fluorescence technique, can generate directional and amplified radiation by the intense interaction between fluorophores and surface plasmons (SPs) of metallic nanofilms. For plasmon-based optical systems, the strong interaction between localized and propagating SPs and "hot spot" structures show great potential to significantly improve the electromagnetic (EM) field and modulate optical properties. Au nanobipyramids (NBPs) with two sharp apexes to enhance and restrict the EM field were introduced through electrostatic adsorption to achieve a mediated fluorescence system, and the emission signal enhancement was realized by factors over 60 compared with the normal SPCE. It has been demonstrated that the intense EM field produced by the NBPs assembly is what triggered the unique enhancement of SPCE by Au NBPs, which effectively overcomes the inherent signal quenching of SPCE for ultrathin sample detection. This remarkable enhanced strategy offers the chance to improve the detection sensitivity for plasmon-based biosensing and detection systems, and expand the range of applications for SPCE in bioimaging with more comprehensive and detailed information acquisition. The enhancement efficiency for various emission wavelengths was investigated in light of the wavelength resolution of SPCE, and it was discovered that enhanced emission for multi-wavelength could be successfully detected through the different emission angles due to the angular displacement caused by wavelength change. Benefit from this, the Au NBP modulated SPCE system was employed for multi-wavelength simultaneous enhancement detection under a single collection angle, which could broaden the application of SPCE in simultaneous sensing and imaging for multi-analytes, and expected to be used for high throughput detection of multi-component analysis.


Assuntos
Corantes Fluorescentes , Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Corantes Fluorescentes/química
5.
Curr Med Sci ; 42(3): 629-634, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35366149

RESUMO

OBJECTIVE: Melanoblasts are the cell source of regeneration for pigment restoration. The ability to differentiate into mature melanocytes is the essential feature of melanoblasts in depigmentation diseases. Cold atmospheric plasma is an ionized gas with near-room temperature and highly reactive species that has been shown to induce stem cell differentiation. The aim of the study was to explore the effect of cold atmospheric plasma on the differentiation of melanoblast progenitor cells. METHODS: In this study, melanoblasts were exposed to the plasma jet and the cell morphology was observed. The cell cycle and cell proliferation were detected. Furthermore, the cell immunofluorescence and the detection of melanin particle and nitric oxide were carried out to investigate the differentiation of melanoblast progenitor cells. RESULTS: Cells that were treated with the plasma had longer and more synaptic structures, and the G1 phase of cell cycle was prolonged in the treated group. More melanin synthesis-related proteins and melanin particles were produced after plasma treatment. Nitric oxide was one of the active components generated by the plasma jet, and the nitric oxide content in the cell culture medium of the treated group increased. CONCLUSION: These results indicate that an increase in nitric oxide production caused by a plasma jet can promote cell differentiation. The application of plasma provides an innovative strategy for the treatment of depigmentation diseases.


Assuntos
Melaninas , Óxido Nítrico , Diferenciação Celular , Proliferação de Células , Melaninas/metabolismo , Melaninas/farmacologia , Melanócitos/metabolismo , Óxido Nítrico/metabolismo
6.
Gene ; 749: 144724, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32360843

RESUMO

Long non-coding RNA (LncRNA) belongs to non-coding RNAs longer than 200 nucleic acids. More and more studies have revealed that lncRNA can participate in the occurrence and pathophysiology of diseases, especially in cancers. Although research on lncRNAs has doubled year by year, little is known about the specific regulatory mechanisms of lncRNAs in diseases. The main purpose of this review is to explore the molecular mechanism and clinical significance of SNHG5 in cancers. We systematically search Pubmed to obtain relevant literature on SNHG5. In this review, the functional role, molecular mechanism, and clinical significance of SNHG5 in human cancers are described in detail. Small nucleolar RNA host gene 5 (SNHG5) has been shown to be involved in the development and tumorigenesis of a variety of cancers (colorectal, bladder, gastric, endometrial, acute lymphocytic leukemia, osteosarcoma, etc.). Its disorder is closely related to metastasis, pathological staging, and prognosis. LncRNA SNHG5 might be a potential and novel diagnostic marker for cancer patients, a target for molecular targeted therapy, and a prognostic diagnostic marker.


Assuntos
Neoplasias/genética , RNA Longo não Codificante/fisiologia , Biomarcadores Tumorais/genética , Humanos , Neoplasias/patologia , Neoplasias/terapia , Prognóstico , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/metabolismo
7.
RSC Adv ; 10(4): 1966-1970, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35494568

RESUMO

A reusable magnetic-quantum dot material (MNP-SiO2-QD) with good magnetic properties and high fluorescence retention was successfully fabricated from linked magnetic nanoparticles and quantum dots. The resulting material can qualitatively and quantitatively detect four kinds of antibiotics and maintain high recovery rates.

8.
J Environ Sci (China) ; 86: 203-212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31787185

RESUMO

Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research topic. Herein, a rationally designed a Cu(II)-based metal-organic gel (Cu-MOG) with a nanoporous 3D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic dyes. The Cu-MOG exhibited high efficiency, with an adsorption capacity of up to 650.32 mg/g, and rapid adsorption efficiency, with the ability to adsorb 80% of Neutral Red within 1 min. The high adsorption efficiency was attributed to its large specific surface area, which enabled it to massively bind cationic dyes through electrostatic interaction, and a nanoporous structure that promoted intra-pore diffusion. Remarkably, the Cu-MOG displayed size-selective adsorption, based on adsorption studies concerning dyes of different sizes as calculated by density functional theory. Additionally, the adsorption performance of the Cu-MOG still maintained removal efficiency of 100% after three regeneration cycles. These results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater.


Assuntos
Corantes/química , Cobre/química , Modelos Químicos , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos
9.
J Microbiol Immunol Infect ; 52(5): 685-692, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31255574

RESUMO

BACKGROUND: Development of an efficacious egg-free mock-up H5N1 vaccine is key to our preparedness against pandemic avian flu. METHODS: This is a single-center, randomized, observer-blinded phase I clinical trial evaluating the safety and immunogenicity of an alum-adjuvanted Madin-Darby canine kidney (MDCK)-derived inactivated whole-virion H5N1 influenza vaccine in healthy adults. Hemagglutination inhibition (HAI) and neutralizing antibody titers were measured using horse and turkey red blood cells (RBCs). RESULTS: Thirty-six adult subjects were randomized to receive two doses of 0.5 mL of the MDCK-derived H5N1 alum-adjuvanted vaccine containing 7.5, 15, or 30 µg of hemagglutinin (HA) 21 days apart. The candidate vaccine was well tolerated and safe across the three dosing groups. The most frequent adverse event was injection site pain (46.5%). Both HAI and neutralizing antibody titers increased after each vaccination in all three dosing groups. The best HAI responses, namely a seroconversion rate of 91.7% and a geometric mean ratio of 9.51 were achieved with the HA dose of 30 µg assayed using horse RBCs at day 42. HAI titers against H5N1 avian influenza virus was significantly higher when measured using horse RBCs compared with turkey RBCs. CONCLUSIONS: This Phase I trial showed the MDCK-derived H5N1 candidate vaccine is safe and immunogenic. The source of RBCs has a significant impact on the measurement of HAI titers (ClinicalTrials.gov number: NCT01675284.).


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Imunogenicidade da Vacina , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Segurança , Adjuvantes Imunológicos/efeitos adversos , Adulto , Compostos de Alumínio/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Aves , Cães , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/fisiopatologia , Feminino , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Cavalos , Humanos , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Influenza Aviária , Injeções Intramusculares , Células Madin Darby de Rim Canino , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Soroconversão , Taiwan , Vacinação/efeitos adversos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Adulto Jovem
10.
Dalton Trans ; 48(11): 3560-3565, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30785438

RESUMO

A hybrid of ZIF-8 with CdS nanorods could increase the transport efficiency of photo-generated charge carriers and the surface area. Notably, through doping Zn ions with a transition metal, in this work, we fabricated a bimetallic ZnM-ZIF (M = Ni, Cu, or Co)-encapsulated CdS nanorod heterostructure for the first time. Compared with ZIF-8, the bimetallic ZIF exhibited a modulated structure, flat band position, and lower overpotential for the hydrogen evolution reaction. ZnM-ZIF not only improved the transfer of water and light, but also boosted the separation of charge carriers. Consequently, the optimized CdS-ZnM-ZIF samples with Cu, Ni, and Co doping showed corresponding photocatalytic hydrogen activities 44, 92, and 59 times larger than that of pristine CdS nanorods. This work provides a new method for better utilization of porous MOF crystals for photocatalysts.

11.
J Asian Nat Prod Res ; 20(11): 1075-1080, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28944690

RESUMO

A new diterpenoid, 17-methyl-8, 13-labdadien-15, 16-olid-19-oic acid methyl ester (1), along with two known compounds 2 and 3, were isolated from the leaves of Platycladus orientalis (L.) Franco. The structures were confirmed based on the analysis of HR-MS, 1D-NMR, and 2D-NMR spectra and the configuration of 1 was confirmed by the single-crystal X-ray diffraction.


Assuntos
Cupressaceae/química , Diterpenos/química , Folhas de Planta/química , Modelos Moleculares , Estrutura Molecular
12.
Dalton Trans ; 46(32): 10553-10557, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28725895

RESUMO

Nanoporous Co-doped Zn1-xCdxS were facilely fabricated via adopting ZIFs as templates, and Cd(NO3)2 and thiourea as precursors. The highly porous microstructure and uniform Co-doping of the photocatalyst afford a high H2-production rate (45.2 and 422.2 times larger than those of Zn0.5Cd0.5S and CdS), providing an effective way for the development of high performance nanoporous photocatalysts.

13.
Chemistry ; 22(24): 8152-7, 2016 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-27136376

RESUMO

Although graphene oxide (GO) has large interlayer spacing, it is still inappropriate to use it as an anode for sodium-ion batteries (SIBs) because of the existence of H-bonding between the layers and ultralow electrical conductivity which impedes the Na(+) and e(-) transformation. To solve these issues, chemical, thermal, and electrochemical procedures are traditionally employed to reduce GO nanosheets. However, these strategies are still unscalable, consume high amounts of energy, and are expensive for practical application. Here, for the first time, we describe the superior Na storage of unreduced GO by a simple and scalable alkali-metal-ion (Li(+) , Na(+) , K(+) )-functionalized process. The various alkali metals ions, connecting with the oxygen on GO, have played different effects on morphology, porosity, degree of disorder, and electrical conductivity, which are crucial for Na-storage capabilities. Electrochemical tests demonstrated that sodium-ion-functionalized GO (GNa) has shown outstanding Na-storage performance in terms of excellent rate capability and long-term cycle life (110 mAh g(-1) after 600 cycles at 1 A g(-1) ) owing to its high BET area, appropriate mesopore, high degree of disorder, and improved electrical conductivity. Theoretical calculations were performed using the generalized gradient approximation (GGA) to further study the Na-storage capabilities of functionalized GO. These calculations have indicated that the Na-O bond has the lowest binding energy, which is beneficial to insertion/extraction of the sodium ion, hence the GNa has shown the best Na-storage properties among all comparatives functionalized by other alkali metal ions.

14.
J Pharm Anal ; 5(1): 12-17, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29403910

RESUMO

A sensitive and selective liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was established to determine 2-oxo-clopidogrel, a crucial intermediate metabolite in human plasma. A chromatographic separation was performed on a Sapphire C18 column following a liquid-liquid extraction sample preparation with methyl t-butyl ether. Detection was carried out on a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) with an electrospray ionization (ESI) mode. The method was validated in terms of specificity, accuracy, precision and limit of quantification. The calibration curves ranged from 0.50 to 50.0 ng/mL with good linearity. The stability was fully validated with addition of 1,4-dithio-DL-threitol (DTT) into the plasma sample prior to and in the preparation procedure. The validated method was proved to be suitable for use in pharmacokinetic study after single oral administration of 75 mg clopidogrel tablets in human subjects, which could make contribution to intensive study of the clinical drug-drug interactions of clopidogrel and individual treatment.

15.
J Mol Model ; 19(12): 5579-86, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24257902

RESUMO

The geometrical structures, energetics properties, and aromaticity of C(36-n) Si(n) (n ≤ 18) fullerene-based clusters were studied using density functional theory calculations. The geometries of C(36-n) Si(n) clusters undergo strong structural deformation with the increase of Si substitution. For the most energy favorable structures of C(36-n) Si(n) , the silicon and carbon atoms form two distinct homogeneous segregations. Subsequently, the binding energy, HOMO-LUMO energy gap, vertical ionization potential, vertical electron affinity, and chemical hardness for the energetic favorable C(36-n) Si(n) geometries were computed and analyzed. In addition, the aromatic property of C(36-n) Si(n) cagelike clusters was investigated, and the result demonstrate that these C(36-n) Si(n) cagelike structures possess strong aromaticity.

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