Improvement of spatial resolution in a Timepix based CdTe photon counting detector using ToT method

Park, Kyeongjin,Lee, Daehee,Lim, Kyung Taek,Kim, Giyoon,Chang, Hojong,Yi, Yun,Cho, Gyuseong Elsevier 2018 Nuclear instruments & methods in physics research. Vol.891 No.-

<P><B>Abstract</B></P> <P>Photon counting detectors (PCDs) have been recognized as potential candidates in X-ray radiography and computed tomography due to their many advantages over conventional energy-integrating detectors. In particular, a PCD-based X-ray system shows an improved contrast-to-noise ratio, reduced radiation exposure dose, and more importantly, exhibits a capability for material decomposition with energy binning. For some applications, a very high resolution is required, which translates into smaller pixel size. Unfortunately, small pixels may suffer from energy spectral distortions (distortion in energy resolution) due to charge sharing effects (CSEs). In this work, we propose a method for correcting CSEs by measuring the point of interaction of an incident X-ray photon by the time-of-threshold (ToT) method. Moreover, we also show that it is possible to obtain an X-ray image with a reduced pixel size by using the concept of virtual pixels at a given pixel size. To verify the proposed method, modulation transfer function (MTF) and signal-to-noise ratio (SNR) measurements were carried out with the Timepix chip combined with the CdTe pixel sensor. The X-ray test condition was set at 80 kVp with 5 μ A, and a tungsten edge phantom and a lead line phantom were used for the measurements. Enhanced spatial resolution was achieved by applying the proposed method when compared to that of the conventional photon counting method. From experiment results, MTF increased from 6.3 (conventional counting method) to 8.3 lp/mm (proposed method) at 0.3 MTF. On the other hand, the SNR decreased from 33.08 to 26.85 dB due to four virtual pixels.</P>

Application of Color Information to Facilitate Finding Books in the Library

Kyeongjin Park,Hyeon Chul Kim,Eun Hye Lee,Kyungdoh Kim 대한인간공학회 2017 大韓人間工學會誌 Vol.36 No.3

Objective: We propose to apply color information to facilitate finding books in the library. Background: Currently, books are classified in the basis of a decimal classification system and a call number in the library. Users find a book using the call number. However, this classification system causes various difficulties. Method: In a process analysis and survey study, we identify what the real problem is and where the problem is occurred. To solve the real problems, we derived a new search method using color information. We conducted a comparative experiment with 48 participants to see whether the new method can show higher performance. Results: The new method using color information showed faster time and higher subjective rating scores than current call number method. Also, the new method showed faster time regardless of the skill level while the call number method showed time differences in terms of the skill level. Conclusion: The effectiveness of the proposed method was verified by experiments. Users will be able to find the desired book without difficulty. This method can improve the quality of service and satisfaction of library use. Application: Our book search method can be applied as a book search tool in a real public library. We hope that the method can provide higher satisfaction to users.

드론 촬영 제어 인터페이스 연구

박경진(Kyeongjin Park),김경도(Kyungdoh Kim) 대한인간공학회 2018 대한인간공학회 학술대회논문집 Vol.2018 No.11

치킨 유형 및 소스별 소비자 선호도 연구

박경진(Kyeongjin Park),안진호(Jinho Ahn),전영호(Young Ho Chun),성동은(Dong Eun Sung),김경도(Kyungdoh Kim) 대한인간공학회 2018 大韓人間工學會誌 Vol.37 No.5

Objective: We conducted an experiment about consumer preferences with chicken types and sauces to provide an implication for chicken menu development. Background: In the food service industry, chicken franchises have studied the consumer preferences for the menu development to enhance its competitiveness. It was necessary to investigate the preferences for the chicken types and the sauces sufficiently since cooking methods and sauces for chicken have been diversified. Method: We compared three types of chickens and four sauces. 30 Participants evaluated each combination of chicken types and sauces in terms of the flavor, texture, appearance and satisfaction. Results: The flavor of chickens with a spicy sauce and no sauces was preferred. The oven chicken with barbecue sauce showed a higher flavor than other chicken combinations, and the crispy chicken with chili sauce had a higher flavor than other chicken combinations. Participants also had higher appearance scores for red sauces. Overall satisfaction was affected by flavor, texture and appearance in order. Conclusion: In chicken menus, fried chicken and spicy chicken must be provided. Barbecue sauce matched well with oven chicken and chili sauce was good for crispy chicken only. When developing new chicken menus, we should focus on flavor and texture. Application: This results can contribute to chicken menu developments to enhance the competitiveness of chicken franchises.

Progress Spinner의 진행 패턴 차이가 사용자의 인지 진행 속도 및 만족도에 미치는 영향 연구

박경진(Kyeongjin Park),김경도(Kyungdoh Kim) 대한산업공학회 2017 대한산업공학회지 Vol.43 No.3

Progress indicators provide information about downloading progress and the remaining time. Two common forms of indicator are bar and spinner. However, most studies have focused on the form of bar. Therefore, we are going to investigate which patterns of progress spinner show better perceived speed and satisfaction. Also the effects of provision of time information were studied. This study provided the progress spinner with different patterns with 4 seconds and 12 seconds download latencies. The participants evaluated overall satisfaction and perceived downloading speed. As a result, ‘Speed Up’ patterns showed the higher perceived downloading speed and satisfaction than ‘Speed Down’ patterns. In 4s situation, it was better with time information was absent. In 12s situation, it was higher in terms of the perceived downloading speed when time information was provided.

Bioactive compounds and antioxidant activity in three types of Korean watery kimchi

Park Hyosun,Kim Suna,Kim Jaecheol,Lee KyeongJin,Moon BoKyung 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

Watery kimchi is a traditional fermented food served with its soup. In this study, we collected 21 samples of yeolmu mul kimchi (YMK), dongchimi (DC), and nabak kimchi (NK), respectively, which are the most popular watery kimchi in Korea. A composite sample of each watery kimchi was prepared for estimation of their bioactive compounds and antioxidant activities. Of the three kimchi types, YMK had the highest total carotenoid content (63.78 ± 4.88 mg/100 g, of which lutein, capsanthin, and β-carotene were the main carotenoids), and DC had the lowest (3.50 ± 0.12 mg/100 g). YMK also had the highest contents of chlorophyll (250.1 ± 3.91 mg/100 g), ascorbic acid (447.16 ± 8.95 mg/100 g), and capsaicinoids (2.51 ± 0.09 mg/100 g) compared to DC and NK. The lactic acid content was highest in NK (582.72 ± 29.10 mg/100 g). Moreover, YMK showed significantly higher antioxidant activity (ABTS and DPPH) than DC and NK (p < 0.05). Chlorophyll and antioxidant activity showed a strong positive correlation (p < 0.01). The results of this study highlighted watery kimchi as a potentially valuable source of bioactive compounds, and the carotenoids and capsaicinoids were affected by the supporting ingredients used in watery kimchi. Furthermore, watery kimchi provides 4.11% of the recommended daily intake of vitamin A according to the 2020 Korean dietary reference intakes.

Homeodomain transcription factor CDX1 is required for the transcriptional induction of PPARγ in intestinal cell differentiation

Park, Min Jung,Kim, Hye Young,Kim, KyeongJin,Cheong, JaeHun Elsevier 2009 FEBS letters Vol.583 No.1

<P><B>Abstract</B></P><P>The caudal-associated homeobox transcription factor, CDX1, performs critical functions in intestinal cell proliferation, differentiation, and neoplasia. In this study, we have identified the molecular mechanism underlying the CDX1-mediated regulation of intestinal cell differentiation. CDX1 enhanced the expression of PPARγ gene, a master transcriptional regulator of intestinal differentiation, at the transcriptional level, via functional interaction with CCAAT/enhancer-binding protein alpha (C/EBPα). Butyrate, an intestinal differentiation inducer, increased the protein interaction of CDX1 and C/EBPα, thereby resulting in a significant increase in PPARγ expression. These results show that the regulation of target gene expression for intestinal determination is dependent on a transcriptional cascade of CDX<B>1</B>, C/EBPα, and PPARγ.</P><P><B>Structured summary</B></P><P>MINT-6800304: <I>CDX1</I> (uniprotkb:P47902) <I>physically interacts</I> (MI:0218) with <I>CEBPalpha</I> (uniprotkb:P49715) by <I>pull down</I> (MI:0096)</P><P>MINT-6800330: <I>CDX1</I> (uniprotkb:P47902) <I>physically interacts</I> (MI:0218) with <I>CEBPalpha</I> (uniprotkb:P49715) by <I>two hybrid</I> (MI:0018)</P><P>MINT-6800315: <I>CEBPalpha</I> (uniprotkb:P49715) <I>physically interacts</I> (MI:0218) with <I>CDX1</I> (uniprotkb:P47902) by <I>anti bait co-immunoprecipitation</I> (MI:0006)</P>

Hydrogen peroxide induces vasorelaxation by enhancing 4-aminopyridine-sensitive Kv currents through <i>S</i> -glutathionylation

Park, Sang Woong,Noh, Hyun Ju,Sung, Dong Jun,Kim, Jae Gon,Kim, Jeong Min,Ryu, Shin-Young,Kang, KyeongJin,Kim, Bokyung,Bae, Young Min,Cho, Hana Springer Berlin Heidelberg 2015 Pfl ugers Arch Vol.467 No.2

<P>Hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>) is an endothelium-derived hyperpolarizing factor. Since opposing vasoactive effects have been reported for H<SUB>2</SUB>O<SUB>2</SUB> depending on the vascular bed and experimental conditions, this study was performed to assess whether H<SUB>2</SUB>O<SUB>2</SUB> acts as a vasodilator in the rat mesenteric artery and, if so, to determine the underlying mechanisms. H<SUB>2</SUB>O<SUB>2</SUB> elicited concentration-dependent relaxation in mesenteric arteries precontracted with norepinephrine. The vasodilatory effect of H<SUB>2</SUB>O<SUB>2</SUB> was reversed by treatment with dithiothreitol. H<SUB>2</SUB>O<SUB>2</SUB>-elicited vasodilation was significantly reduced by blocking 4-aminopyridine (4-AP)-sensitive Kv channels, but it was resistant to blockers of big-conductance Ca<SUP>2+</SUP>-activated K<SUP>+</SUP> channels and inward rectifier K<SUP>+</SUP> channels. A patch-clamp study in mesenteric arterial smooth muscle cells (MASMCs) showed that H<SUB>2</SUB>O<SUB>2</SUB> increased Kv currents in a concentration-dependent manner. H<SUB>2</SUB>O<SUB>2</SUB> speeded up Kv channel activation and shifted steady state activation to hyperpolarizing potentials. Similar channel activation was seen with oxidized glutathione (GSSG). The H<SUB>2</SUB>O<SUB>2</SUB>-mediated channel activation was prevented by glutathione reductase. Consistent with <I>S</I>-glutathionylation, streptavidin pull-down assays with biotinylated glutathione ethyl ester showed incorporation of glutathione (GSH) in the Kv channel proteins in the presence of H<SUB>2</SUB>O<SUB>2</SUB>. Interestingly, conditions of increased oxidative stress within MASMCs impaired the capacity of H<SUB>2</SUB>O<SUB>2</SUB> to stimulate Kv channels. Not only was the H<SUB>2</SUB>O<SUB>2</SUB> stimulatory effect much weaker, but the inhibitory effect of H<SUB>2</SUB>O<SUB>2</SUB> was unmasked. These data suggest that H<SUB>2</SUB>O<SUB>2</SUB> activates 4-AP-sensitive Kv channels, possibly through <I>S</I>-glutathionylation, which elicits smooth muscle relaxation in rat mesenteric arteries. Furthermore, our results support the idea that the basal redox status of MASMCs determines the response of Kv currents to H<SUB>2</SUB>O<SUB>2</SUB>.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1007/s00424-014-1513-3) contains supplementary material, which is available to authorized users.</P>

Hepatitis C virus NS5A protein increases hepatic lipid accumulation via induction of activation and expression of PPARgamma

Kim, KyeongJin,Kim, Kook Hwan,Ha, Eunsin,Park, Jin Young,Sakamoto, Naoya,Cheong, JaeHun Elsevier 2009 FEBS letters Vol.583 No.17

<P><B>Abstract</B></P><P>Steatosis is an established risk factor for disease progression in cases of chronic hepatitis C. Recently it was demonstrated that Hepatitis C virus (HCV) core and non-structural (NS) 2 proteins (NS2) induce lipid accumulation in hepatic cells. However, it has yet to be determined whether other HCV proteins are associated with lipid metabolism. The NS5A augmented the transcriptional activity and gene expression of PPARγ. Furthermore, NS5A increased the ability to recruit the transcriptional coactivator PGC-1s to the PPRE with PPARγ, as well as the interaction with PPARγ2 and PGC-1α. Our results indicate that NS5A may exploit multiple strategies that enhance PPARγ-induced lipid accumulation.</P><P><B>Structured summary</B></P><P>MINT-7229685: <I>PPAR gamma 2</I> (uniprotkb:P37231-2) <I>physically interacts</I> (MI:0914) with <I>PGC1 alpha</I> (uniprotkb:Q9UBK2) by <I>pull down</I> (MI:0096)</P><P>MINT-7229712: <I>PPAR gamma 2</I> (uniprotkb:P37231-2) <I>physically interacts</I> (MI:0914) with <I>NS5A</I> (uniprotkb:P26662) by <I>pull down</I> (MI:0096)</P><P>MINT-7229698: <I>PPAR gamma 2</I> (uniprotkb:P37231-2) <I>physically interacts</I> (MI:0914) with <I>PGC1 alpha</I> (uniprotkb:Q9UBK2) by <I>anti tag coimmunoprecipitation</I> (MI:0007)</P><P>MINT-7229731: <I>PPAR gamma 2</I> (uniprotkb:P37231-2) <I>physically interacts</I> (MI:0914) with <I>NS5A</I> (uniprotkb:P26662) by <I>anti tag coimmunoprecipitation</I> (MI:0007)</P>

연분홍색 겹꽃 분화용 카네이션 ‘마일드플로라’ 육성

정경진(Kyeongjin Jeong),박현근(Hyun Gun Park),안혜빈(Hye Bin An),송재기(Jae Ki Song),김선영(Sun Youn Kim),권기범(Ki Bum Kweon),배민지(Min Ji Bae),진영돈(Young Don Chin),장영호(Young Ho Chang) 한국원예학회 2022 한국원예학회 학술발표요지 Vol.2022 No.5