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1.
J Nanosci Nanotechnol ; 18(9): 6106-6111, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29677751

RESUMO

In order to improve EQE, we have investigated on the role of multilayer graphene (MLG) on the electrical and optical properties of GaN based light-emitting diodes (LEDs) with ultrathin ITO (5 nm or 10 nm)/p-GaN contacts. The MLG was transferred on the ITO/p-GaN to decrease sheet resistance of thin ITO p-electrode and improve the current spreading of LEDs. The LEDs with the ITO 5 nm and MLG/ITO 5 nm structures showed 3.25 and 3.06 V at 20 mA, and 11.69 and 13.02 mW/sr at 400 mA, respectively. After forming MLG on ITO 5 nm, the electro-optical properties were enhanced. Furthermore, the GaN based-LEDs applied to the ITO 10 nm, and MLG/ITO (10 nm) structures showed 2.95 and 3.06 V at 20 mA, and 20.28 and 16.74 mW/sr at 400 mA, respectively. The sheet resistance of the MLG transferred to ITO 5 nm was decreased approximately four fold compared to ITO 5 nm. On the other hand, the ITO 10 nm and MLG/ITO 10 nm showed a similar sheet resistance; the transmittance of the LEDs with ITO 10 nm decreased to 16% due to MLG formation on ITO. This suggests that the relationship between the sheet resistance and transmittance according to the ITO film thickness affected the electro-optical properties of the LEDs with a transparent p-electrode with the MLG/ITO dual structure.

2.
J Neurosci Res ; 93(8): 1267-78, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25711470

RESUMO

Monoamine oxidase B (MAO-B) is well known as a therapeutic target for Parkinson's disease (PD). MAO-B inhibitors retain antiparkinsonism abilities to improve motor function and prevent neuronal loss by decreasing dopamine metabolism and oxidative stress in the brain. From the study to find novel antiparkinsonism drugs that can inhibit MAO-B activity, neuronal loss, and behavioral deficits in the mouse model of PD, we identified that 1-[2-(4-benzyloxyphenoxy)ethyl]imidazole (BPEI) or safinamide strongly and selectively inhibited MAO-B activities in a dose-dependent manner (IC50 of BPEI and safinamide for MAO-B were 0.016 and 0.0021 µM and for MAO-A were 70.0 and 370 µM, respectively). In ex vivo studies after an administration (30 mg/kg, i.p.) of BPEI or safinamide to normal mice, the MAO-B activity in the brain was reduced by up to 90.6% or 82.4% at 1.0 hr. BPEI (20 mg/kg, i.p.) or safinamide (20 mg/kg, i.p.) significantly reversed the behavioral impairments, dopamine levels in the striatum, and neuronal loss in the substantia nigra of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice compared with the MPTP-alone-treated group. In the 6-hydroxydopamine-induced PD rat model, behavioral improvement by levodopa sparing activity was observed in the BPEI- or safinamide-treated (20 mg/kg, i.p.) rats. Moreover, BPEI revealed additional curative activities for nonmotor symptoms of PD such as pain, anxiety, epilepsy, and depression in rodent disease models. Therefore, BPEI has broad therapeutic potential for treating motor symptoms via strong and selective inhibitory effects on MAO-B, with additional benefits for comorbid symptoms in PD.


Assuntos
Modelos Animais de Doenças , Imidazóis/uso terapêutico , Intoxicação por MPTP/enzimologia , Intoxicação por MPTP/prevenção & controle , Inibidores da Monoaminoxidase/uso terapêutico , Neurônios/enzimologia , Animais , Contagem de Células , Imidazóis/farmacologia , Intoxicação por MPTP/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Doença de Parkinson/enzimologia , Doença de Parkinson/patologia , Doença de Parkinson/prevenção & controle , Ratos , Ratos Sprague-Dawley
3.
Sensors (Basel) ; 14(9): 17159-73, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25225876

RESUMO

To correct an over-exposure within an image, the over-exposed region (OER) must first be detected. Detecting the OER accurately has a significant effect on the performance of the over-exposure correction. However, the results of conventional OER detection methods, which generally use the brightness and color information of each pixel, often deviate from the actual OER perceived by the human eye. To overcome this problem, in this paper, we propose a novel method for detecting the perceived OER more accurately. Based on the observation that recognizing the OER in an image is dependent on the saturation sensitivity of the human visual system (HVS), we detect the OER by thresholding the saturation value of each pixel. Here, a function of the proposed method, which is designed based on the results of a subjective evaluation on the saturation sensitivity of the HVS, adaptively determines the saturation threshold value using the color and the perceived brightness of each pixel. Experimental results demonstrate that the proposed method accurately detects the perceived OER, and furthermore, the over-exposure correction can be improved by adopting the proposed OER detection method.


Assuntos
Algoritmos , Biomimética/métodos , Percepção de Cores/fisiologia , Colorimetria/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Fotografação/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
Heliyon ; 8(11): e11320, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36387531

RESUMO

This study investigates the relations between the shape of hydrologic responses and the dynamic transport properties of channel networks within the framework of random walks on fractal networks, focusing on the shape parameter of Nash model. To this end, we evaluate the static fractal structures and the dynamic transport properties of various channel networks and, then, validate Liu's conjecture (1992) for the shape of hydrologic responses. In the context of random walks on fractal networks, the fractal dimensions of channel networks can directly connect the static structure to the dynamic transport properties of channel networks through Horton's law of drainage composition. It is observed that the peak coordinates of hydrologic responses would have a more intimate relation to the connectivity of channel networks than the conductivity of those. The characteristic times of hydrologic responses also tend to be related to the connectivity of channel networks. Thereby, the shape of hydrologic responses would be expected directly affected by the fractal dimension of channel networks in terms of their static structure, while interpreted a combined result of the conductivity and the connectivity of channel networks in terms of their dynamic transport properties. So, the runoff hydrographs of a river basin could be considered shaped by the fractal dimensions of its channel networks following the linear hydrologic system theory.

5.
Integr Med Res ; 7(1): 77-84, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29629294

RESUMO

BACKGROUND: The Yin-Yang is a pivotal concept of traditional East-Asian medicine, however the stability of Yin-Yang temperament in Sasang Personality Questionnaire (SPQ) over time has not been extensively studied. The purpose of this study was to examine the test-retest validity of SPQ with a large number of participants. METHODS: SPQ test was conducted two times with three months interval in 247 Korean university students. The structural validity of first SPQ data was examined with Factor analysis and Cronbach's alpha, and the correlation between first and second measure of SPQ was attested with Pearson's correlation. Yang, Uncertain and Yin temperament groups were determined with SPQ total scores, and agreement of temperament group clustering between first and second measures were analyzed with Cohen's Kappa. RESULTS: Three subscales of SPQ explained 55.25% of total variances, and internal consistency of SPQ total score was 0.772. The correlation coefficient between first and second measures of SPQ were 0.851 and 0.888 in male and female, respectively, and the agreement of first and second Yin-Yang temperament group clustering as Cohen's Kappa was 0.536 for male and 0.637 for female. CONCLUSION: The repeatability of SPQ measuring Yin-Yang temperament at three months of interval was found to be satisfactory. The SPQ would be a reliable clinical measure for the biopsychological studies of traditional East-Asian medicine.

6.
Integr Med Res ; 6(2): 156-164, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28664139

RESUMO

BACKGROUND: Animation characters are created to embody distinctive personalities and body images; however, these features have not been analyzed with objective measures based on East Asian theory. The purpose of this study was to analyze the biopsychological features of seven animation characters in Pororo the Little Penguin, which scored unprecedented success in Korea, with clinically validated and standardized measures of Sasang typology. METHODS: Forty-one graduate students completed a survey examining body mass index (BMI) and Sasang Personality Questionnaire (SPQ) of seven characters in Pororo the Little Penguin after watching three selected episodes. The differences in physical appearance and psychological traits among animation characters were analyzed with analysis of variance. RESULTS: SPQ and BMI showed distinctive biopsychological features of seven animation characters. Pororo (28.29 ± 6.38 and 36.61 ± 3.09) was a typical So-Yang type boy, Petty (20.98 ± 4.07 and 31.66 ± 4.59) was a typical So-Yang type girl, and Loopy (28.05 ± 6.60 and 22.78 ± 4.78) was a typical So-Eum type girl in terms of BMI and SPQ, respectively. The BMI and SPQ of Poby (41.10 ± 4.26 and 22.32 ± 3.48) and Harry (19.63 ± 5.17 and 37.61 ± 2.40) showed the most obvious contrast. CONCLUSION: This study showed that SPQ and BMI are useful objective measures for analyzing the biopsychosocial features of animation characters as well as patients. The interdisciplinary research methodology of Sasang typology suggested here would provide useful tools for educating healthcare professionals and the general public about Korean medicine, and also contribute to the development of animation characters.

7.
World J Gastroenterol ; 22(10): 2981-92, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26973394

RESUMO

AIM: To investigate prevalence and risk factors for colorectal neoplasms in adults aged < 50 years, for whom screening is not recommended. METHODS: This cross-sectional study compared prevalence and characteristics of colorectal and advanced adenomas in patients aged < 50 years who underwent colonoscopy screening with subjects aged ≥ 50 years. To evaluate risk factors for colorectal and advanced adenoma in young adults, we used multivariable logistic regression models. Colorectal neoplasm characteristics were evaluated and compared with those in older patients. RESULTS: Among 2819 patients included, prevalences of colorectal adenoma and advanced adenoma were 19.7% and 1.5%, respectively. As patient age increased, so did the prevalence of colorectal neoplasm. However, prevalence of advanced adenoma did not differ between age-groups 45-49 years and ≥ 50 years (OR = 0.43, 95%CI: 0.17-1.07, P = 0.070). In younger age-group (< 50 years), colorectal adenoma was significantly associated with older age, waist circumference (OR = 1.72, 95%CI: 1.15-2.55, P = 0.008), and current smoking (OR = 1.60, 95%CI: 1.07-2.41, P = 0.023). Alcohol consumption was an independent risk factor for colorectal advanced adenoma (OR = 3.69, 95%CI: 1.08-12.54, P = 0.037). Multiple neoplasms and large neoplasms (≥ 1 cm) were more prevalent in subjects ≥ 50 years. CONCLUSION: Current screening strategies for colorectal cancer may need to be amended to account for patient age, especially in young subjects with abdominal obesity, current smoking and alcohol consumption.


Assuntos
Pólipos Adenomatosos/epidemiologia , Pólipos do Colo/epidemiologia , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer , Pólipos Adenomatosos/patologia , Adulto , Idade de Início , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Distribuição de Qui-Quadrado , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/patologia , Estudos Transversais , Detecção Precoce de Câncer/métodos , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Obesidade Abdominal/epidemiologia , Razão de Chances , Valor Preditivo dos Testes , Prevalência , República da Coreia/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
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