Extremely sensitive and selective sub-ppm CO detection by the synergistic effect of Au nanoparticles and core–shell nanowires

Kim, Jae-Hun,Mirzaei, Ali,Kim, Hyoun Woo,Kim, Sang Sub Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.249 No.-

<P><B>Abstract</B></P> <P>An extremely sensitive CO sensor based on novel hybrid SnO<SUB>2</SUB>–ZnO core–shell (C–S) nanowires (NWs) functionalized by Au nanoparticles (NPs) was synthesized. First, networked SnO<SUB>2</SUB> NWs were successfully prepared using the vapor–liquid–solid growth method on an electrode layer with special patterns. A ZnO shell was subsequently coated on the SnO<SUB>2</SUB> core using atomic layer deposition, and Au NPs were then attached onto the ZnO shell using γ-ray radiolysis. The resulting sensor exhibited a very high response of 26.6–100ppb CO gas. Furthermore, the responses to other gases such as C<SUB>6</SUB>H<SUB>6</SUB> and C<SUB>6</SUB>H<SUB>7</SUB> were extremely low, indicating the very good selectivity of the sensor to CO gas. Besides acting as heterojunctions, the catalytic effect of the Au NPs on CO gas greatly improved the CO sensing capability of the Au-functionalized SnO<SUB>2</SUB>–ZnO C–S NWs. The high sensitivity and selectivity of this sensor can open a path for prompt toxic monitoring and early detection of fatal diseases related to CO.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel hybrid SnO<SUB>2</SUB>–ZnO core–shell nanowires functionalized by Au nanoparticles. </LI> <LI> The resulting sensor exhibited a very high response of 26.6–100ppb CO gas. </LI> <LI> The very good selectivity of the sensor to CO gas. </LI> <LI> Heterojunctions and the catalytic effect of Au greatly improved the CO sensing capability. </LI> </UL> </P>

Resistive switching characteristic of Ce0.9Y0.1O2/ TiO2 bi‑layer structure by photochemical metal‑organic deposition

Sung‑Eun Kim,Jin-Gyu Lee,In-Young Choi,Ha-Eun Kim,Hong-Sub Lee 한국세라믹학회 2020 한국세라믹학회지 Vol.57 No.1

Sneak current is one of the main bottlenecks for dense crossbar array resistive random access memory. This study reports highly non-linear resistive switching characteristic from Ce0.9Y0.1O2/ TiO2 bi-layer (1S/1R device) structure, fabricated by photochemical metal-organic deposition, as a solution for sneak current issue. Ce0.9Y0.1O2 material, possessing oxygen vacancies, was used as a potential barrier as well as oxygen reservoir which rectified the current of low resistance state without an electrical breakdown in 1S/1R device. TiO2 was adopted for resistive switching property, and TiO2 layer having mixed phase (anatase and brookite) showed typical diode switching behavior. The photochemical reaction of photochemical metal-organic deposition process and phase formation were monitored and established using by Fourier-transform infrared spectroscopy and X-ray diffraction, respectively. The 1S/1R device showed highly non-linear resistive switching characteristic, large on/ off ratio of above three orders of magnitude with low operating current.

Haplogroup Classification of Korean Cattle Breeds Based on Sequence Variations of mtDNA Control Region

Kim, Jae-Hwan,Lee, Seong-Su,Kim, Seung Chang,Choi, Seong-Bok,Kim, Su-Hyun,Lee, Chang Woo,Jung, Kyoung-Sub,Kim, Eun Sung,Choi, Young-Sun,Kim, Sung-Bok,Kim, Woo Hyun,Cho, Chang-Yeon Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.5

Many studies have reported the frequency and distribution of haplogroups among various cattle breeds for verification of their origins and genetic diversity. In this study, 318 complete sequences of the mtDNA control region from four Korean cattle breeds were used for haplogroup classification. 71 polymorphic sites and 66 haplotypes were found in these sequences. Consistent with the genetic patterns in previous reports, four haplogroups (T1, T2, T3, and T4) were identified in Korean cattle breeds. In addition, T1a, T3a, and T3b sub-haplogroups were classified. In the phylogenetic tree, each haplogroup formed an independent cluster. The frequencies of T3, T4, T1 (containing T1a), and T2 were 66%, 16%, 10%, and 8%, respectively. Especially, the T1 haplogroup contained only one haplotype and a sample. All four haplogroups were found in Chikso, Jeju black and Hanwoo. However, only the T3 and T4 haplogroups appeared in Heugu, and most Chikso populations showed a partial of four haplogroups. These results will be useful for stable conservation and efficient management of Korean cattle breeds.

Acute and Sub-chronic Oral Toxicity Study of Ammonium Persulfate in Spraque-Dawley Rats

Kim, Yong-Soon,Baek, Min-Won,Sung, Jae-Hyuck,Ryu, Hyun-Youl,Kim, Jin-Sik,Cho, Hyun-Sun,Choi, Byung-Gil,Song, Min-Sub,Song, Moon-Yong,Baik, Eun-Ju,Choi, Young-Kuk,Kim, Jong-Kyu,Yu, Il-Je,Song, Kyung-Se Korean Society of ToxicologyKorea Environmental Mu 2009 Toxicological Research Vol.26 No.3

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 mg/kg body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 mg/kg body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 mg/kg body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.

2,4-bis (p-hydroxyphenyl)-2-butenal (HPB242) induces apoptosis via modulating E7 expression and inhibition of PI3K/Akt pathway in SiHa human cervical cancer cells.

Kim, Man Sub,Kim, Jung Hee,Bak, Yesol,Park, Yun Sun,Lee, Dong Hun,Kang, Jeong Woo,Shim, Jung-Hyun,Jeong, Heon Sang,Hong, Jin Tae,Yoon, Do Young Lawrence Erlbaum Associates, Publishers [etc.] 2012 Nutrition and cancer Vol.64 No.8

<P>The Maillard reaction is a chemical reaction occurring between an amino acid and a reducing sugar, usually requiring thermal processing. Maillard reaction products (MRPs) have antioxidant, antimutagenic, and antibacterial effects, and although 2,4-bis (p-hydroxyphenyl)-2-butenal (HPB242), a fructose-tyrosine MRP, appears to inhibit proliferation of cancer cells, its mechanism of action has not been studied in detail. We found that HPB242 treatment modulated expression of cyclins and tumor suppressor genes in SiHa human cervical cancer cell lines: cyclins and phospho-pRB were downregulated, whereas the expression of CDK inhibitors and p53 was enhanced. HPB242 induced apoptosis dose-dependently by suppressing E7 expression and leading to sub-G1 cell-cycle arrest in SiHa cell lines; treatment also led to the proteolytic cleavage of caspase-3, -9, and poly (ADP-ribose) polymerase. Moreover, HPB242 upregulated Fas expression, altered expressions of pro- and antiapoptotic factors, and also inhibited nuclear translocation of nuclear factor κB and phosphorylation of IκB. HPB242 treatment decreased phosphatidyl inositol-3 kinase and p-Akt expression levels, demonstrating that this survival pathway may also be inhibited by HPB242. Cumulatively, HPB242 promotes apoptosis by influencing E7 expression, inducing cell-cycle arrest at sub-G1 phase, and promoting both intrinsic (mitochondrial) and extrinsic (Fas-dependent) apoptosis in SiHa human cervical cancer cells.</P>

철도시스템분야 실무적용을 위한 RAM Guidance 개발에 관한 연구

이중섭(Joong Sub31 Lee),백영구(Young Goo Baek),이진(Jin Lee),한미정(Mi Jung Han),김성환(Sung Hwan Kim) 한국철도학회 2015 한국철도학회 학술발표대회논문집 Vol.2015 No.10

철도시스템 기술 고도화 및 복잡성의 증대와 더불어 발주기관으로부터 시스템의 성능보증과 안전성 확보가 요구되고 있는 실정이다. 또한 국내 철도안전법 강화로 인하여 시스템 보증활동의 중요성이 증가되고 있다. 본 논문에서는 국제철도관련 규격을 바탕으로 철도시스템의 RAM 업무에 대한 절차를 정의하고, 해당 철도 프로젝트에서 RAM 업무를 원활히 수행할 수 있도록 관련된 국제 규격 및 유사시스템 적용 사례에 기반하여 철도시스템 개발 특성을 고려한 RAM 업무 수행 지침(Guidance)을 개발하였다. Performance and safety assurances for the railway system are required by the client because of the high degree of technology and increased complexity. In addition, as a result of reinforced domestic railway safety laws, the importance of system assurance activity has been growing steadily. This paper defines the task of the RAM process based on international railway industry standards for RAMS engineers to work efficiently and develops the RAM guidance considering the railway system characteristics based on domestic standards and application cases of railway systems.

Acute and Sub-chronic Oral Toxicity Study of Ammonium Persulfate in Spraque-Dawley Rats

Yong Soon Kim,Min Won Baek,Jae Hyuck Sung,Hyun Youl Ryu,Jin Sik Kim,Hyun Sun Cho,Byung Gil Choi,Min Sub Song,Moon Yong Song,Eun Ju Baik,Young Kuk Choi,Jong Kyu Kim,Il Je Yu,Kyung Seuk Song 한국독성학회 2009 Toxicological Research Vol.25 No.3

The toxicity test of ammonium persulfate was conducted to ensure of its potential toxic effects according to the single-dose acute oral toxicity study (OECD Guideline 423) and 90-day repeated dose sub-chronic oral toxicity study guideline (OECD Guideline 408) for establishing national chemical management system, and matching in the Globally Harmonized Classification System (GHS) category. In acute oral toxicity study, pasty stool, perineal contamination and temporary body weight decrease were observed after dosing 1st and 2nd challenge (300 ㎎/㎏ body weight). All test animals were dead within 6 hours after dosing at 3rd challenge (2000 ㎎/㎏ body weight). Therefore, the GHS class of test substance is considered class 4. In sub-chronic toxicity study, body weight changes, food consumptions, hematological, biochemical and pathological examination did not show any noticeable and significant differences between the administered (5, 20, 80 ㎎/㎏ body weight) and control (vehicle only) group animals. Based on these results, the no observed adverse effect level (NOAEL) is considered above 80 mg/kg body weight.

학생검도선수 학부모의 만족도 척도 개발

김무진(Moo-Jin Kim),박상섭(Sang-Sub Park) 대한검도학회 2015 대한검도학회지 Vol.26 No.1

본 연구는 학생검도선수 학부모의 만족도를 측정할 수 있는 척도 개발을 목적으로 이루어졌다. 선행 연구를 바탕으로 전문가 회의와 두 차례의 예비 조사를 통해 7개 요인의 42문항으로 구성된 설문지를 이용해 자료를 수집하였다. 자료의 수집대상으로는 전국학생검도대회에 참가한 학부모를 선정하였으며 대회장에서 직접 설문지를 배부하여 회수하였다. 자료 분석에 이용된 설문지는 총 368부이다. 분석 방법으로 먼저 문항분석을 거쳐 타당성 검증을 위해 실시한 탐색적 요인분석에서 Q11, Q24, Q34번 문항이 두 요인에서 .40을 나타내 일차적으로 제거되었다. 이후 신뢰도 확보를 위해 Cronbach"s ɑ값과 문항제거시 척도(Alpha if Item Deleted)를 구했으며 전 문항이 이 기준에 부합하는 것으로 나타났다. 그리고 확인적 요인분석을 실시하였다. 척도의 수용 가능성을 확인할 수 있는 모델의 적합도 지수가 부적합하여 SMC값이 낮은 문항부터 차례로 제거해 Q33, Q30, Q06, Q04, Q19, Q40, Q41, Q18, Q20, Q26문항을 제거한 후 적합도 지수는 수용가능한 지수를 나타내게 되었다. 이러한 과정을 통해 최종 7개 요인의 29문항으로 구성된 학생검도선수 학부모의 만족도 척도를 개발하였다. 이 척도는 집중타당성과 판별타당성을 통해 타당성 평가를 실시하였다. 논의에서는 차후의 연구에서 고려되어야 할 자료 수집 방법과 객관성을 제고할 수 있는 적합도 지수에 대한 논의가 필요함을 제시하였다. The purpose of this study was to development of scale of parents’ of Kumdo Student-Athletes Satisfaction Scale. The preliminary survey was completed over the course of the 16th middle and high school Kumdo Association Fall Conference parents" to attend a survey of 368 people was conducted final data analysis was used. Collected data were analyzed by SPSS 19.0 and AMOS 19.0. The results of this study are as follow First, through the item analysis of seven sub-factors (Guidance actions, Career guidance, Guidance of the appropriateness, motivation, Humanity Education, Leadership qualities, Training Environment) and the full 29-question questionnaire was derived. Second, exploratory factor analysis was conducted. And produce a variety of fit measure the results of applying the model in this study was appropriate. The feasibility study also confirmed the results of different evaluation methods show that the model could be applicable. Finally, 7 sub-factors and the full 29-question questionnaire was completed.

Prediction of Decompensation and Death in Advanced Chronic Liver Disease Using Deep Learning Analysis of Gadoxetic Acid-Enhanced MRI

Heo Subin,이승수,Kim So Yeon,Lim Young-Suk,Park Hyo Jung,Yoon Jee Seok,Suk Heung-Il,Sung Yu Sub,Park Bumwoo,Lee Ji Sung 대한영상의학회 2022 Korean Journal of Radiology Vol.23 No.12

Objective: This study aimed to evaluate the usefulness of quantitative indices obtained from deep learning analysis of gadoxetic acid-enhanced hepatobiliary phase (HBP) MRI and their longitudinal changes in predicting decompensation and death in patients with advanced chronic liver disease (ACLD). Materials and Methods: We included patients who underwent baseline and 1-year follow-up MRI from a prospective cohort that underwent gadoxetic acid-enhanced MRI for hepatocellular carcinoma surveillance between November 2011 and August 2012 at a tertiary medical center. Baseline liver condition was categorized as non-ACLD, compensated ACLD, and decompensated ACLD. The liver-to-spleen signal intensity ratio (LS-SIR) and liver-to-spleen volume ratio (LS-VR) were automatically measured on the HBP images using a deep learning algorithm, and their percentage changes at the 1-year follow-up (ΔLS-SIR and ΔLS-VR) were calculated. The associations of the MRI indices with hepatic decompensation and a composite endpoint of liver-related death or transplantation were evaluated using a competing risk analysis with multivariable Fine and Gray regression models, including baseline parameters alone and both baseline and follow-up parameters. Results: Our study included 280 patients (153 male; mean age ± standard deviation, 57 ± 7.95 years) with non-ACLD, compensated ACLD, and decompensated ACLD in 32, 186, and 62 patients, respectively. Patients were followed for 11–117 months (median, 104 months). In patients with compensated ACLD, baseline LS-SIR (sub-distribution hazard ratio [sHR], 0.81; p = 0.034) and LS-VR (sHR, 0.71; p = 0.01) were independently associated with hepatic decompensation. The ∆LS-VR (sHR, 0.54; p = 0.002) was predictive of hepatic decompensation after adjusting for baseline variables. ∆LS-VR was an independent predictor of liver-related death or transplantation in patients with compensated ACLD (sHR, 0.46; p = 0.026) and decompensated ACLD (sHR, 0.61; p = 0.023). Conclusion: MRI indices automatically derived from the deep learning analysis of gadoxetic acid-enhanced HBP MRI can be used as prognostic markers in patients with ACLD.

Sodium butyrate has context-dependent actions on dipeptidyl peptidase-4 and other metabolic parameters

Lee, Eun-Sol,Lee, Dong-Sung,Pandeya, Prakash Raj,Kim, Youn-Chul,Kang, Dae-Gil,Lee, Ho-Sub,Oh, Byung-Chul,Lee, Dae Ho The Korean Society of Pharmacology 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.5

Sodium butyrate (SB) has various metabolic actions. However, its effect on dipeptidyl peptidase 4 (DPP-4) needs to be studied further. We aimed to evaluate the metabolic actions of SB, considering its physiologically relevant concentration. We evaluated the effect of SB on regulation of DPP-4 and its other metabolic actions, both in vitro (HepG2 cells and mouse mesangial cells) and in vivo (high fat diet [HFD]-induced obese mice). Ten-week HFD-induced obese C57BL/6J mice were subjected to SB treatment by adding SB to HFD which was maintained for an additional 16 weeks. In HepG2 cells, SB suppressed DPP-4 activity and expression at sub-molar concentrations, whereas it increased DPP-4 activity at a concentration of $1,000{\mu}M$. In HFD-induced obese mice, SB decreased blood glucose, serum levels of insulin and $IL-1{\beta}$, and DPP-4 activity, and suppressed the increase in body weight. On the contrary, various tissues including liver, kidney, and peripheral blood cells showed variable responses of DPP-4 to SB. Especially in the kidney, although DPP-4 activity was decreased by SB in HFD-induced obese mice, it caused an increase in mRNA expression of $TNF-{\alpha}$, IL-6, and $IL-1{\beta}$. The pro-inflammatory actions of SB in the kidney of HFD-induced obese mice were recapitulated by cultured mesangial cell experiments, in which SB stimulated the secretion of several cytokines from cells. Our results showed that SB has differential actions according to its treatment dose and the type of cells and tissues. Thus, further studies are required to evaluate its therapeutic relevance in metabolic diseases including diabetes and obesity.