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1.
Small Methods ; : e2300969, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38095424

RESUMEN

The surface treatment for a polymer-ceramic composite is additionally performed in advanced material industries. To prepare the composite without a surface treatment, the simplest way to manufacture an advanced ceramic-particle is devised. The method is the formation of a nanocrystalline composite layer through the simple liquid-phase sintering. Using magnesia (MgO) which shows hydrophilicity, a nanocrystalline surface layer is realized by liquid-phase sintering. The amorphous matrix of nanocrystalline composite layer makes MgO hydrophobic and ensures miscibility with polymers, and the nanocrystalline MgO ensures high thermal conductivity. In addition, the liquid phase removes the open pores and makes the surface morphology smooth MgO with smooth surface (MgO-SM). Thermal interface materials (TIM) prepared with MgO-SM and epoxy show a high thermal conductivity of ≈7.5 W m-1 K-1 , which is significantly higher than 4.5 W m-1 K-1 of pure MgO TIM. Consequently, the formation process of a nanocrystalline surface layer utilizing simple liquid-phase sintering is proposed as a fabrication method for a next-generation ceramic-filler. In addition, it is fundamentally identified that the thermal conductivity of MgO depends on the Mg deficiency, and therefore a poly-crystal MgO-SM (produced at a low temperature) has a higher thermal conductivity than a single-crystal MgO (produced at a high temperature).

2.
Stud Health Technol Inform ; 294: 864-865, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35612227

RESUMEN

We extracted major topic by applying natural language processing and keyword extracting using TF, TF-IDF, TextRank, Yake, KeyBERT. 1452 consultation data were collected from the website and official hospital e-mail. We found six topics categorized into "Medical opinion" related to hospital characteristics and "Non-medical service guidance". Based on this result, it is necessary to establish marketing plan and develop a digital solution for effective consultation.


Asunto(s)
Procesamiento de Lenguaje Natural , Derivación y Consulta , Hospitales , Humanos
3.
Asia Pac J Oncol Nurs ; 8(4): 377-384, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34159230

RESUMEN

OBJECTIVE: This study aimed to investigate the differences in symptom experience, inner strength, adherence, and quality of life (QOL) according to the perception of the new normal, and identify the factors related to the QOL of breast cancer patients undergoing adjuvant hormonal therapy based on the theory of inner strength in women. METHODS: This cross-sectional study recruited patients with breast cancer receiving adjuvant hormonal therapy in the National Cancer Center. Demographic and clinical characteristics were recorded, and patients were assessed using the M. D. Anderson Symptom Inventory, Connor-Davidson Resilience Scale 2, Morisky Medication Adherence Scale 8, and Functional Assessment of Cancer Therapy-General Scale. RESULTS: After the breast cancer diagnosis, the perception of the new normal showed a significant dependence on pill count and emotional and functional well-being. The hierarchical regression analysis indicated that the new normal, symptom interference, and inner strength after adjusting for age, time since diagnosis, and receiving chemotherapy were significant predictors of QOL in breast cancer patients receiving adjuvant endocrine therapy. The model accounted for 47.8% of the variance in QOL. CONCLUSIONS: The theory of inner strength might be a potential pathway in health care to improve patients' QOL during long-term medication. The results of this study have both theoretical and applied implications. The findings can be utilized as evidence for developing an effective intervention that improves the QOL and adherence to adjuvant hormonal therapy of breast cancer patients.

4.
Nat Commun ; 11(1): 2509, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32427846

RESUMEN

UV-activated alkyne-alkene [2 + 2] cycloaddition has served as an important tool to access cyclobutenes. Although broadly adopted, the limitations with UV light as an energy source prompted us to explore an alternative method. Here we report alkyne-alkene [2 + 2] cycloaddition based on visible light photocatalysis allowing the synthesis of diverse cyclobutenes and 1,3-dienes via inter- and intramolecular reactions. Extensive mechanistic studies suggest that the localized spin densities at sp2 carbons of alkenes account for the productive sensitization of alkenes despite their similar triplet levels of alkenes and alkynes. Moreover, the efficient formation of 1,3-dienes via tandem triplet activation of the resulting cyclobutenes is observed when intramolecular enyne cycloaddition is performed, which may serve as a complementary means to the Ru(II)-catalyzed enyne metathesis. In addition, the utility of the [2 + 2] cycloaddition has been demonstrated by several synthetic transformations including synthesis of various extended π-systems.

5.
Proteomics ; : e1900367, 2020 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-32468700

RESUMEN

Protein arginine methyltransferase 5 (PRMT5) is a major enzyme responsible for generating monomethyl and symmetric dimethyl arginine in proteins. PRMT5 is essential for cell viability and development, and its overexpression is observed in a variety of cancers. In the present study, it is found that levels of PRMT5 protein and symmetric arginine dimethylation in colorectal cancer (CRC) tissues are increased compared to those in adjacent noncancerous tissues. Using immunoaffinity enrichment of methylated peptides combined with high-resolution mass spectrometry, a total of 147 symmetric dimethyl-arginine (SDMA) sites in 94 proteins are identified, many of which are RNA binding proteins and enzymes. Quantitative analysis comparing CRC and normal tissues reveals significant increase in the symmetric dimethylation of 70 arginine sites in 46 proteins and a decrease in that of four arginine sites in four proteins. Among the 94 proteins identified in this study, it is confirmed that KH-type splicing regulatory protein is a target of PRMT5 and highly expressed in CRC tissues compared to noncancerous tissues. This study is the first comprehensive analysis of symmetric arginine dimethylation using clinical samples and extends the number of known in vivo SDMA sites. The data obtained are available via ProteomeXchange with the identifier PXD015653.

6.
ACS Appl Mater Interfaces ; 9(42): 37006-37012, 2017 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-29022691

RESUMEN

The transparent characteristic of dye-sensitized solar cells (DSCs) makes them suitable for building integrated photovoltaic (BIPV) devices. However, the diffusive scattering layer, which is usually used to increase the efficiency of these devices, greatly lowers the transparency of the DSC. This paper described a two-dimensional (2D) photonic crystal (PC) reflector with a sub-micrometer characteristic length that can improve the efficiency of these devices while maintaining transparency. This 2D PCs were fabricated directly onto TiO2 photoelectrodes using colloidal lithography and have the structure of a nanopillar array. A nanopillar with a height of 430 nm was observed to selectively reflect up to 40% of the light of 400-500 nm wavelength. The perceived transparency of the 2D PC electrode was 52%, which is much higher than 0.3% of the conventional scattering layer. The DSC fabricated using the 2D PC electrode demonstrated a maximum photon-to-electric conversion efficiency of 8.23%, which is 18% higher than the pristine electrode. The 2D PC is a highly efficient and wavelength-selective reflector that can be applied to various photoelectric conversion devices.

7.
Chem Commun (Camb) ; 53(45): 6054-6064, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28516179

RESUMEN

This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N-O and C-H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N-O and C-H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines.

8.
Chem Commun (Camb) ; 53(24): 3481-3484, 2017 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-28276553

RESUMEN

An efficient synthetic method for carbazoles has been developed employing diazo anilinoalkynes as substrates. Sequential activation of the orthogonal functional groups embedded in diazo anilinoalkyne substrates by tandem gold-copper catalysis leads to the formation of highly substituted carbazoles. Substrate scope reveals a broad tolerability toward the substitution on aryl groups.

9.
Langmuir ; 32(31): 7735-40, 2016 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-27463514

RESUMEN

The in situ gelation that utilizes the dissolution of polymers inside the cell is allowed high concentration polymer gel without concerns regarding high viscous electrolyte incorporation into the cell as in the conventional approach. We demonstrate the in situ gelation of polymer composite electrolytes using poly(vinylidene fluoride) nanospheres (PVdF NSs). The PVdF NSs were synthesized by high pressure emulsion polymerization using gaseous vinylidene fluoride monomers. Compared to the liquid electrolyte (LE) DSCs without PVdF gelation, the PVdF polymer gel electrolyte (PGE) DSCs displayed higher η than the LE DSCs; specifically, the 10 wt % PVdF PGE DSCs display 8.1% of the η, while the LE DSCs only display 6.5%. We characterized the effect of PVdF PGE on the photovoltaic parameters in detail. We also compared the long-term stability of DSCs containing LE and PVdF PGE. The DSCs with PVdF PGE exhibited high stability compared to the LE DSCs, similar to a conventional PGE system. We believe that this facile in situ gelation approach could be utilized for not only the practical application of polymer gel electrolytes DSCs but also for various energy-storage devices.

10.
Sci Rep ; 4: 5375, 2014 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-25005580

RESUMEN

Dye-sensitised solar cells (DSCs) are a promising substitute for conventional silicon solar cells. A scattering layer of submicrometer pores or particles has been widely introduced to achieve a high light-harvesting efficiency. However, many such fabrication processes require high temperatures and multiple steps to prepare the scattering layer. Here, we have developed an in-situ fabrication process for a macroporous (MP) scattering film. The macropores were formed inside the assembled cell via the dissolution of polystyrene (PS) spheres from a PS/TiO2 composite layer caused by exposure to an electrolyte solution. Specifically, the in-situ MP scattering layer decreased the transmittance of the electrode film from 58% to below 1%. The DSCs using these MP scattering layers exhibited an increase in the efficiency of 22%. Moreover, the dissolution of the PS improved the cell stability because of the gelation of the electrolyte solution; the efficiency of the DSCs was maintained at 80% of its initial value after ageing for 20 days, whereas the efficiency of the bare-electrode DSCs was found to have decreased by 50%. We believe that in-situ porous scattering layers show great promise for next-generation flexible DSCs. Moreover, this approach can be extended to various applications that utilize porous film/liquid systems.

11.
Nanoscale ; 6(6): 3105-9, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24356878

RESUMEN

The effectiveness of the 1D nanorod (NR)-planted 3D inverse opal (IO) structure as an electrode for dye-sensitized solar cells (DSSCs) is demonstrated here. The NRs were grown on the surface of a macroporous IO structure and their longitudinal growth increased the surface area of the structure proportional to the growth duration. NR/IO electrodes with various NR growth times were compared. A remarkable JSC was obtained for the DSSCs utilizing a NR/IO electrode. The improvement of the JSC was analyzed in terms of its efficiency in light harvesting and electron transport. The growth of the NRs improved the dye adsorption density and scattering property of the electrode, resulting in an improvement in the light harvesting efficiency. Electrochemical impedance analysis revealed that the NRs also improved its electron transport properties. Further growth of the NRs tended to limit the increase of the JSC, which could be attributed to an overlap between them.


Asunto(s)
Colorantes/química , Nanotubos/química , Energía Solar , Espectroscopía Dieléctrica , Electrodos , Electrones , Porosidad
12.
ACS Appl Mater Interfaces ; 4(7): 3589-95, 2012 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-22738020

RESUMEN

The nonconventional bottom-up growth of TiO2 was first demonstrated in the preparation of hierarchical TiO2 electrodes for use in highly efficient dye-sensitized solar cells. The simple immersion of a substrate in a precursor solution enabled the growth of TiO2 particulate films. Here, we have implemented a hierarchical growth strategy in which two stages of controlled growth yielded first macroscale TiO2 particles, followed by mesoscale TiO2 particles. We successfully fabricated electrode films up to 20 µm thick via a growth rate of 0.3 µm/min. The specific area of the electrodes was controlled via the deposition of mesoscale TiO2 particles. The deposited particles displayed a rutile phase with an average size of several tens of nanometers in diameter, as confirmed by XRD and high-resolution TEM imaging. After depositing the second layer of mesoscale TiO2 particles, the photocurrent density increased by a factor of 3. A maximum efficiency of 6.84% was obtained for the hierarchically structured TiO2 electrodes under 1 sun illumination. The hierarchical TiO2 electrodes were compared with macroporous TiO2 electrodes, revealing that the higher photocurrent density could be attributed to a longer electron recombination lifetime and a high specific area. The longer recombination lifetime was supported by the presence of fewer defective TiO2 surfaces, as confirmed by the XPS spectrum.

13.
Taehan Kanho Hakhoe Chi ; 38(4): 629-38, 2008 Aug.
Artículo en Coreano | MEDLINE | ID: mdl-18753815

RESUMEN

PURPOSE: This was a methodological research to develop an instrument to assess the emotional response of family members of physically restrained patients. METHODS: A primary instrument with 68 questions was developed based on literature review and semi-structured interviews with family members. A group of experts revised individual questions and removed 4 irrelevant questions. This secondary instrument, then, was tested with 199 family members of physically restrained patients in intensive care units of a university hospital. The validity and reliability of the instrument were tested by factor analysis. RESULTS: After item analysis, 3 questions with a correlation coefficient under .30 were discarded and the questions with a factor loading under .45 on Varimax Rotation were also removed. After factor analysis on the final 37 questions, 7 factors were identified; avoidance, shock, helplessness, grudge, depression, anxiousness, and acceptance. The total variance explained was 55.63%. The reliability of this instrument was 0.93 of Cronbach's alpha. CONCLUSION: This instrument was statistically reliable and valid to measure family's emotional response to physical restraints of the patients. This instrument can be useful in assessing the effects of nursing interventions for family members of restrained patients.


Asunto(s)
Familia/psicología , Desarrollo de Programa , Restricción Física , Adolescente , Adulto , Niño , Emociones , Femenino , Humanos , Unidades de Cuidados Intensivos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
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