• Title/Summary/Keyword: Q4A

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Usefulness of Acoustic Noise Reduction in Brain MRI Using Quiet-T2 (뇌 자기공명영상에서 Quiet-T2 기법을 이용한 소음감소의 유용성)

  • Lee, SeJy;Kim, Young-Keun
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.51-57
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    • 2016
  • Acoustic noise during magnetic resonance imaging (MRI) is the main source for patient discomfort. we report our preliminary experience with this technique in neuroimaging with regard to subjective and objective noise levels and image quality. 60 patients(29 males, 31 females, average age of 60.1) underwent routine brain MRI with 3.0 Tesla (MAGNETOM Tim Trio; Siemens, Germany) system and 12-channel head coil. Q-$T_2$ and $T_2$ sequence were performed. Measurement of sound pressure levels (SPL) and heart rate on Q-$T_2$ and $T_2$ was performed respectively. Quantitative analysis was carried out by measuring the SNR, CNR, and SIR values of Q-$T_2$, $T_2$ and a statistical analysis was performed using independent sample T-test. Qualitative analysis was evaluated by the eyes for the overall quality image of Q-$T_2$ and $T_2$. A 5-point evaluation scale was used, including excellent(5), good(4), fair(3), poor(2), and unacceptable(1). The average noise and peak noise decreased by $15dB_A$ and $10dB_A$ on $T_2$ and Q-$T_2$ test. Also, the average value of heartbeat rate was lower in Q-$T_2$ for 120 seconds in each test, but there was no statistical significance. The quantitative analysis showed that there was no significant difference between CNR and SIR, and there was a significant difference (p<0.05) as SNR had a lower average value on Q-$T_2$. According to the qualitative analysis, the overall quality image of 59 case $T_2$ and Q-$T_2$ was evaluated as excellent at 5 points, and 1 case was evaluated as good at 4 points due to a motion artifact. Q-$T_2$ is a promising technique for acoustic noise reduction and improved patient comfort.

Association of Colony Morphology with Coenzyme $Q_{10}$ Production and Its Enhancement from Rhizobium radiobacter T6102W by Addition of Isopentenyl Alcohol as a Precursor

  • Seo, Myung-Ji;Kook, Moo-Chang;Kim, Soon-Ok
    • Journal of Microbiology and Biotechnology
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    • v.22 no.2
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    • pp.230-233
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    • 2012
  • Rhizobium radiobacter T6102 was morphologically purified by the aniline blue agar plates to give two distinct colonies; white smooth mucoid colony (T6102W) and blue rough colony (T6102B). The coenzyme $Q_{10}$ ($CoQ_{10}$) was produced just by T6102W, showing 2.0 mg/g of $CoQ_{10}$ content, whereas the T6102B did not produce the $CoQ_{10}$. All of the used $CoQ_{10}$ biosynthetic precursors enhanced the $CoQ_{10}$ production by T6102W. Specifically, the supplementation of 0.75 mM isopentenyl alcohol improved the $CoQ_{10}$ concentration (19.9 mg/l) and content (2.4 mg/g) by 42% and 40%, respectively.

SYMMETRIC IDENTITIES FOR DEGENERATE CARLITZ-TYPE q-EULER NUMBERS AND POLYNOMIALS

  • RYOO, CHEON SEOUNG
    • Journal of applied mathematics & informatics
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    • v.37 no.3_4
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    • pp.259-270
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    • 2019
  • In this paper we define the degenerate Carlitz-type q-Euler polynomials by generalizing the degenerate Euler numbers and polynomials, degenerate Carlitz-type Euler numbers and polynomials. We also give some interesting properties, explicit formulas, a connection with degenerate Carlitz-type q-Euler numbers and polynomials.

Development of Quantitative Real-Time PCR Primers for Detection of Streptococcus sobrinus

  • Park, Soon-Nang;Kook, Joong-Ki
    • International Journal of Oral Biology
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    • v.41 no.3
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    • pp.149-154
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    • 2016
  • The purpose of this study was to develop Streptococcus sobrinus-specific qPCR primers based on the nucleotide sequence of the RNA polymerase ${\beta}-subunit$ gene (rpoB). The specificity of the primers was determined by conventional polymerase chain reaction (PCR) with 12 strains of S. sobrinus and 50 strains (50 species) of non-S. sobrinus bacteria. The sensitivity of the primers was determined by quantitative real-time PCR (qPCR) with serial dilutions of the purified genomic DNAs (40 ng to 4 fg) of S. sobrinus ATCC $33478^T$. The specificity data showed that the S. sobrinus-specific qPCR primers (RTSsob-F4/RTSsob-R4) detected only the genomic DNAs of S. sobrinus strains with a detection limit of up to 4 fg of S. sobrinus genomic DNA. Our results suggest that the RTSsob-F4/RTSsob-R4 primers are useful in detecting S. sobrinus with high sensitivity and specificity for epidemiological studies of dental caries..

Protective Effects of Quercetin-3-O-glucuronide against 1-methyl-4-phenylpyridinium-induced Neurotoxicity (1-methyl-4-phenylpyridinium으로 유도된 신경 손상에 대한 quercetin-3-O-glucuronide의 보호 효과)

  • Pariyar, Ramesh;Bastola, Tonking;Seo, Jungwon
    • Journal of Life Science
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    • v.29 no.2
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    • pp.191-197
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    • 2019
  • Parkinson's disease (PD) is a progressive neurodegenerative disease that mainly affects motor system with clinical features such as bradykinesia, rigidity, tremor and abnormal posture. PD is characterized by the death of dopaminergic neurons in the substantia nigra pars compacta, which is associated with accumulation of oxidative stress and dysregulation of intracellular signaling pathway. Quercetin-3-O-glucuronide (Q3GA), a major metabolite of quercetin, has been reported to have neuroprotective effects. In this study, we examined the neuroprotective effect of Q3GA against 1-methyl-4-phenyl pyridinium ($MPP^+$)-induced neurotoxicity of PD and the underlying molecular mechanisms in SH-SY5Y cells. MTT and LDH assay showed that Q3GA significantly decreased $MPP^+$-induced cell death, which is accompanied by a reduction in poly (ADP-ribose) polymerase (PARP) cleavage. Furthermore, it attenuated $MPP^+$-induced intracellular reactive oxygen species (ROS) with the reduction of Bax/ Bcl-2 ratio. Moreover, Q3GA significantly increased the phosphorylation of Akt and cAMP response element binding protein (CREB), but it has no effects on the phosphorylation of extracellular signal-regulated kinase (ERK). Taken together, these results demonstrate that Q3GA significantly attenuates $MPP^+$-induced neurotoxicity through ROS reduction and Akt/CREB signaling pathway in SH-SY5Y cells. Our findings suggest that Q3GA might be one of the potential candidates for the prevention and/or treatment of PD.

Analyzing College Students' Perception of Quality Computer Class (좋은 컴퓨터 수업에 대한 대학생들의 인식 유형 분석)

  • Kim, Dugyu;Lee, Jaemu
    • Journal of The Korean Association of Information Education
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    • v.24 no.3
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    • pp.225-232
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    • 2020
  • This study is to clarify how college students think about quality computer classes. Q methodology is applied to extract the subjective thinking of college students. After extracting the statements through students' interviews and advanced study, the 54 Q samples were selected. The P sample consisted of 50 college students. They performed Q sort against the Q sample questionnaire. The Q sort results were analyzed by performing QUANL program. As a result of the analysis, four types of perceptions of quality computer classes based on college students' ideas were extracted. There were no differences between male and female students, but there was a clear difference between general college and teacher's college students by type. The types were divided into four categories which we named as follows: is 'Value change-oriented class through creative problem-solving', is 'Improving computer application skills through the learner's competition', is 'Improving advanced computer technology with programming skills' and is 'Learner centered pleasant class'.

A Study on the Pole-Q Reduction of Chebyshev Function Using Trade-off (트레이드 오프를 이용한 Chebyshev 함수의 극점-Q 감소에 관한 연구)

  • 윤창훈;최석우
    • The Journal of the Acoustical Society of Korea
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    • v.19 no.5
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    • pp.79-83
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    • 2000
  • When passband ripple α/sub p/ and stopband attenuation α/sub s/ at the w/sub s/ where the stopband begins are specified in filter design, △α/sub s/ usually exceeds the specification by △α/sub s/ due to the necessity that the order n of the filter function be an integer. In this paper, we apply a trade-off method to remove the excess stopband attenuation △α/sub s/ for reducing the value of pole-Q and improving the characteristics of the Chebyshev filter function. We also apply the trade-off method of pole-Q reduction to the modified Chebyshev function, and then the 4 types of function have been analyzed to compare in frequency and time domain characteristics. The trade-off method reduces the pole-Q which influences the filter characteristics to maximum 49.6% without increase of the order n. Thus implies that they have the improved characteristics such as the reduced passband ripple and flatter delay characteristics as compared Chebyshev filter function before trade-off. And the unit step response shows shorter delay time and settling time in time domain performance.

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A Study on US Consumer's Subjectivity Schemata of Sharing Economy: Q Methodology (공유경제에 관한 미국 소비자의 주관성 가치체계 연구 : Q 방법론의 적용)

  • Kim, Ki-youn
    • Journal of Internet Computing and Services
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    • v.19 no.4
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    • pp.107-121
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    • 2018
  • The purpose of this study is to explore the present US consumer behavioral trends and various cognitive schema types for sharing economy frame and shared service. For this, by applying Q methodology, this paper theoretically defines three differentiated typologies of US consumer in a interpretive perspective. This study is in-depth focused on discovering and categorizing characteristics of a respondent's thinking structure called 'schemata'. According to the entire procedures of Q methodology, this paper analyzed Q-sorted data from twenty-four people in the basis of forty Q-samples (statements). Consequently, we discovered four consumer groups named as Type 1 'Socialsumer', Type 2 'Smarsumer', Type 3 'Researsumer'.

A FIXED POINT APPROACH TO THE STABILITY OF THE FUNCTIONAL EQUATION RELATED TO DISTANCE MEASURES

  • Shiny, Hwan-Yong;Kim, Gwang Hui
    • Korean Journal of Mathematics
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    • v.24 no.2
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    • pp.297-305
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    • 2016
  • In this paper, by using fixed point theorem, we obtain the stability of the following functional equations $$f(pr,qs)+g(ps,qr)={\theta}(p,q,r,s)f(p,q)h(r,s)\\f(pr,qs)+g(ps,qr)={\theta}(p,q,r,s)g(p,q)h(r,s)$$, where G is a commutative semigroup, ${\theta}:G^4{\rightarrow}{\mathbb{R}}_k$ a function and f, g, h are functionals on $G^2$.