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1.
iScience ; 27(6): 109905, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799561

RESUMO

Tropical cyclone (TC) intensity change forecasting remains challenging due to the lack of understanding of the interactions between TC changes and environmental parameters, and the high uncertainties resulting from climate change. This study proposed hybrid convolutional neural networks (hybrid-CNN), which effectively combined satellite-based spatial characteristics and numerical prediction model outputs, to forecast TC intensity with lead times of 24, 48, and 72 h. The models were validated against best track data by TC category and phase and compared with the Korea Meteorological Administrator (KMA)-based TC forecasts. The hybrid-CNN-based forecasts outperformed KMA-based forecasts, exhibiting up to 22%, 110%, and 7% improvement in skill scores for the 24-, 48-, and 72-h forecasts, respectively. For rapid intensification cases, the models exhibited improvements of 62%, 87%, and 50% over KMA-based forecasts for the three lead times. Moreover, explainable deep learning demonstrated hybrid-CNN's potential in predicting TC intensity and contributing to the TC forecasting field.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 308: 123779, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38128323

RESUMO

Multidimensional ABX3 hybrid perovskites three-dimensionally confined dot-shaped structure demonstrate versatile potential to photoelectrochemical cells for water splitting, hydrogen generation, solar cells, and light-emitting diodes. To apply perovskite quantum dots (PQDs) to solar-driven chemistry and optoelectronic devices, understanding the photoinduced charge carrier dynamics of PQDs under electrochemical conditions or applied bias are important. In this study, the detailed transformation mechanism of formamidinium lead iodide perovskite quantum dots under electrochemical conditions was studied by tracking the products of the reaction through cyclic voltammetry, X-ray photoemission spectroscopy, in-situ UV-visible spectroelectrochemistry, etc. Through comprehensive characterizations, the mechanism of irreversible oxidative transformation of perovskite quantum dots was presented. This study provides deeper insight into the electrochemical behavior of PQDs for successful solar-driven chemistry and optoelectronic device applications.

3.
iScience ; 26(11): 108123, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37876825

RESUMO

Previous heat risk assessments have limitations in obtaining accurate heat hazard sources and capturing population distributions, which change over time. This study proposes a diurnal heat risk assessment framework incorporating spatiotemporal air temperature and real-time population data. Daytime and nighttime heat risk maps were generated using hazard, exposure, and vulnerability components in Seoul during the summer of 2018. The hazard was derived from the daily extreme air temperatures obtained using the stacking machine learning model. Exposure was calculated using de facto population density, and vulnerability was assessed using demographic and socioeconomic indicators. The resulting maps revealed distinct diurnal spatial patterns, with high-risk areas in the urban core during the day and dispersed at night. Daytime heat risk was strongly correlated with heat-related illness ratios (R = 0.8) and accurately captured temporal fluctuations in heat-related illness incidence. The proposed framework can guide site-specific adaptation and response plans for dynamic urban heat events.

4.
Nanomaterials (Basel) ; 13(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37764611

RESUMO

Lubricant (or oil)-impregnated porous surface has been considered as a promising surface treatment to realize multifunctionality. In this study, silicone oil was impregnated into a hard porous oxide layer created by the plasma electrolytic oxidation (PEO) of aluminum (Al) alloys. The monolayer of polydimethylsiloxane (PDMS) from silicone oil is formed on a porous oxide layer; thus, a water-repellent slippery oil-impregnated surface is realized on Al alloy, showing a low contact angle hysteresis of less than 5°. This water repellency significantly enhanced the corrosion resistance by more than four orders of magnitude compared to that of the PEO-treated Al alloy without silicone oil impregnation. The silicone oil within the porous oxide layer also provides a lubricating effect to improve wear resistance by reducing friction coefficients from ~0.6 to ~0.1. In addition, because the PDMS monolayer can be restored by frictional heat, the water-repellent surface is tolerant to physical damage to the oxide surface. Hence, the results of this fundamental study provide a new approach for the post-treatment of PEO for Al alloys.

5.
Nanomaterials (Basel) ; 13(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36903685

RESUMO

Slippery liquid-infused porous surface (SLIPS) realized on commercial materials provides various functionalities, such as corrosion resistance, condensation heat transfer, anti-fouling, de/anti-icing, and self-cleaning. In particular, perfluorinated lubricants infused in fluorocarbon-coated porous structures have showed exceptional performances with durability; however, they caused several issues in safety, due to their difficulty in degradation and bio-accumulation. Here, we introduce a new approach to create the multifunctional lubricant-impregnated surface with edible oils and fatty acid, which are also safe to human body and degradable in nature. The edible oil-impregnated anodized nanoporous stainless steel surface shows a significantly low contact angle hysteresis and sliding angle, which is similar with general surface of fluorocarbon lubricant-infused systems. The edible oil impregnated in the hydrophobic nanoporous oxide surface also inhibits the direct contact of external aqueous solution to a solid surface structure. Due to such de-wetting property caused by a lubricating effect of edible oils, the edible oil-impregnated stainless steel surface shows enhanced corrosion resistance, anti-biofouling and condensation heat transfer with reduced ice adhesion.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36078784

RESUMO

This study aims to analyze factors influencing citizens' intentions to take protective action against particulate matter (PM) and their actual actions in response to PM. There were few research on the role of government factors and the issue of intention-action inconsistency in the context of PM mitigation action. Therefore, this study set not only variables in the risk perception paradigm but also ones in government factors as independent variables, while intention and action in response to PM were set as dependent variables. This study's analysis was based on survey data collected from Korean people. For representativeness of the samples, this study adopted the quota sampling method, considering region, gender, and age. Five hundred respondents finished the survey. To verify the hypotheses, this study used regression and binomial logistic analysis. Analysis showed that (1) negative emotions, trust, knowledge, government competency, policy satisfaction, and policy awareness had significant effects on intention and action in response to PM, and (2) perceived benefits only affected intention, whereas government accountability only affected action. Logistic analysis showed that there were groups in which intentions and actions did not match. Negative emotions and government competence induce intention-action consistency, whereas the perceived benefits and trust in government tend to encourage inconsistency. Knowledge is a variable that induces both consistency and inconsistency in the intention-action relationship. The determinant structures of independent variables affecting the likelihood of belonging to the four groups differed.


Assuntos
Mudança Climática , Intenção , Governo , Humanos , Material Particulado , Percepção , Inquéritos e Questionários
7.
Analyst ; 147(5): 841-850, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35119443

RESUMO

Organic-inorganic hybrid perovskites are widely utilized in solar driven chemistry such as photocatalysis, hydrogen evolution, and oxygen reduction. Hybrid perovskites contain various components with high polarity and/or charge values, which undergo transformations due to ion exchange, photoinduced phase segregation, or ion migration. These variable characteristics make perovskites "soft materials". Meanwhile, optoelectronic devices often operate under electrochemical reactions in the presence of an electrical field. To examine the effect of this field on the material/photophysical properties of hybrid perovskites, hybrid FAPbBr3 (FA+: CH(NH2)2+) perovskite quantum dots (PQDs) were synthesized. In this study, we report the spectroelectrochemical investigation of the hybrid FAPbBr3 PQDs to understand the electrochemical stability and degradation process. We also found that the electrochemical condition played an important role in inducing defect-mediated oxidation/reduction reactions, changing the photophysical properties of hybrid PQDs, and causing their irreversible transformations to various lead halide plumbate complexes. These findings can help develop a strategy for enhancing the operational performance of PQDs for the solar driven chemistry.

9.
Yonsei Med J ; 62(1): 86-90, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33381938

RESUMO

Precise allergy diagnosis and effective allergen specific immunotherapy are largely dependent on the quality of allergen extract. A new extract of Dermatophagoides farinae was commercially developed by Prolagen. The allergenic properties of the new extract were compared with those of other commercial products. The allergenic properties of the new extract were compared according to protein concentration, protein profiles, major allergen (Der f 1) contents, and allergenic potency to those for three commercially available extracts imported in Korea (Jubilant HollisterStier Allergy, Lofarma S.p.A., and Stallergenes Greer). Protein concentrations varied up to 2.62-fold (0.404 to 1.057 mg/mL), and Der f 1 contents varied up to 11.3-fold (3.597 to 40.688 µg/mL). Protein profiles of the extracts showed no major discrepancies, although there were some differences in SDS-PAGE band intensities, reflecting protein concentrations. Allergen potency ranged from 37038 to 60491 PAU/mL. The Prolagen product was highest in terms of protein concentration and allergen potency. The Lofarma product displayed Der f 1 content similar to that in Prolagen (19.4 µg/mg vs. 19.3 µg/mg). Endotoxin levels varied 8.9-fold (1020 to 8985 EU/mL). The newly developed house dust mite extract showed equal or better allergenic properties than available commercial extracts. This new product may be useful for better diagnostics and allergen-specific immunotherapeutics.


Assuntos
Alérgenos/imunologia , Antígenos de Dermatophagoides/imunologia , Hipersensibilidade/etiologia , Animais , Dessensibilização Imunológica , Humanos , Hipersensibilidade/terapia , Pyroglyphidae/imunologia , República da Coreia
10.
Nanotechnology ; 31(26): 265302, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32131063

RESUMO

The etch characteristics of Si and TiO2 nanostructures for optical devices were investigated using pulse biased inductively coupled plasmas (ICP) with SF6/C4F8/Ar and BCl3/Ar, respectively, and the results were compared with those etched using continuous wave (CW) biased ICP. By using pulse biasing compared to CW biasing in the etching of the line/pillar nanostructures with various aspect ratios, there was a reduction of the aspect ratio dependent etching (ARDE) and therefore, uniform etch depths for nanostructures with different pattern widths, as well as the improvement of the etch profiles without any notching, were obtained not only for silicon nanostructures but also for TiO2 nanostructures. The investigation has determined that the improvement of etch profiles and reduced ARDE effect when using pulse biasing are related to the decreased surface charging caused by neutralization of the surface and the improved radical adsorption (or etch byproduct removal) on the etched surfaces during the pulse-off period for pulse biasing compared to CW biasing.

11.
Abdom Radiol (NY) ; 45(1): 161-167, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31784777

RESUMO

PURPOSE: To investigate volume changes of the gallbladder at computed tomography (CT) following bowel preparation for colonoscopy and to evaluate the incidence of gallbladder contraction at abdominal sonography performed with colonoscopy on the same day. METHODS: During a 1-year period, 222 patients underwent abdominal CT (CT1) and colonoscopy on the same day. Among them, 123 patients had prior CT imaging without receiving colonoscopy in the past were enrolled. Manual estimates of 3D gallbladder volume were obtained from two CT scans to evaluate whether gallbladder volume changed as a result of bowel preparation for colonoscopy. During the same 1-year period, another 89 patients underwent abdominal sonography and colonoscopy on the same day (sonography group). The short-axis diameters of the gallbladder on the longitudinal scan of sonography from these patients were obtained. RESULTS: Gallbladder volume was significantly larger on prior CT without colonoscopy (31.7 ± 15.4 cm3) than on CT1 (20.3 ± 11.1 cm3) (p < 0.001). Gallbladder volume decreased by more than 50% in 41 of 123 patients (33%) who underwent abdominal CT and colonoscopy on the same day, compared with standard CT. In the sonography group (n = 89), the short-axis diameters of the gallbladder were less than 1.5 cm in 41 patients (46%) and less than 1.0 cm in 17 patients (19%). CONCLUSION: Contracted gallbladder secondary to bowel preparation can be seen on imaging when performed with same-day colonoscopy. Such a situation may lead to the incomplete or inadequate evaluation of the gallbladder on imaging with same-day colonoscopy.


Assuntos
Colonoscopia , Vesícula Biliar/anatomia & histologia , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Vesícula Biliar/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Retrospectivos , Adulto Jovem
12.
World Neurosurg ; 130: 546-549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31181360

RESUMO

BACKGROUND: Rete mirabile is a very rare vascular malformation and superior cerebellar artery (SCA) rete mirabile is not reported previously. We report a new case of rete mirabile of SCA initially detected by magnetic resonance imaging and transfemoral cerebral angiography. CASE DESCRIPTION: This report illustrates the case of a 58-year-old man who presented with vertical diplopia. Brain magnetic resonance angiography and transfemoral cerebral angiography revealed a rete mirabile of SCA and 3-dimensional volume isotropic turbo spin echo acquisition, brain magnetic resonance imaging sequence, demonstrated that the cisternal segment of the ipsilateral trochlear nerve was compressed by this vascular malformation. We assumed that his cranial nerve palsy was caused by the rete mirabile of the right SCA. During the 8 weeks presence of diplopia, the patient was observed and the symptom was relieved spontaneously. CONCLUSIONS: We provide a first report in the literature of rete mirabile involving the SCA and suggest a descriptive knowledge of rete mirabile for clinicians during decision-making of treatment.


Assuntos
Cerebelo/irrigação sanguínea , Cerebelo/patologia , Transtornos Cerebrovasculares/diagnóstico , Doenças do Nervo Troclear/etiologia , Cerebelo/diagnóstico por imagem , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/patologia , Humanos , Masculino , Pessoa de Meia-Idade
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