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Antioxidant Activities and Cytoprotective Effects of Lonicera japonica Thunb. Extract and Fraction against Oxidative Stress (인동덩굴 추출물과 분획물의 항산화 활성 및 산화적 스트레스에 대한 세포 보호 효과)

  • Lee, Ye Seul;Yun, Mid Eum;Lee, Yun Ju;Park, Young Min;Lee, Sang Lae;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.46 no.1
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    • pp.18-28
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    • 2018
  • In this study, the antioxidant activities and cytoprotective effects against oxidative stress of Lonicera japonica Thunb. 50% ethanol extract and ethyl acetate fraction were investigated. Using the 1,1-diphenyl-2-picrylhydrazyl assay, the free radical scavenging activity (FSC50) of L. japonica Thunb. 50% ethanol extract and ethyl acetate fraction was determined as 152.00 and $77.25{\mu}g/ml$, respectively. To measure the reactive oxygen species (ROS) scavenging activity, the total antioxidant capacity (OSC50) was determined by using a luminol-dependent chemiluminescence assay. The antioxidant activity of the ethyl acetate fraction ($0.33{\mu}g/ml$) was approximately four times stronger than that of the 50% ethanol extract ($1.12{\mu}g/ml$). The protective effect against $^1O_2$-induced cellular damage of human erythrocytes (${\tau}_{50}$) was 46.0 min at $10{\mu}g/ml$ of the 50% ethanol extract and 52.3 min at $1{\mu}g/ml$ of the ethyl acetate fraction. We also investigated the cytoprotective effects against oxidative stress induced by $H_2O_2$ and the intracellular ROS scavenging activity in response to UVB irradiation and found that the extract and fraction protected human skin cells from damage and reduced ROS. These results confirmed that L. japonica Thunb. was a valuable plant-derived natural antioxidant with potential for development as an antioxidative functional ingredient.

Nanostructures of diblock copolymers under curved confinement

  • Shin, Kyu-Soon;Huh, June;Jo Won-Ho;Xiang hongqi;McCarthy Thomas J.;Russell Thomas P.
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.294-294
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    • 2006
  • Diblock copolymers whose morphology in the bulk is dictated by the volume fraction of the components and segmental interactions were confined within nanoscopic cylindrical pores. Since the confining geometry is nonplanar and nanoscopic, the extreme imposed curvature, comparable to molecular dimensions, places significant packing frustration on the chains. When incommensurability between the repeating period of diblock copolymers and the diameter of nanopore is coupled with the curvature, it causes the marked departures from bulk or even thin film behavior. The entropy penalty from the constraints and the curvature of the physical confinement determines unique nanostructures available only with this curved confinement.

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Laser sensor wavelength interrogation using a long-period fiber grating (장주기 격자를 이용한 광섬유 레이저센서의 파장변화 측정)

  • Song, Min-Ho;Lee, Sang-Bae;Choi, Sang-Sam;Nam, Hui;Lee, Byoung-Ho
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.34D no.12
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    • pp.83-88
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    • 1997
  • We present a fiber laser sensor that uses a fiber grating as a strain sensor head and an end-reflector of the laser cavity. A passive wavelength. The long-period grating band-rejection filter showed a wide usable filter wavelength range of about 25 nm, and the intensity of transmitted light increased by 16% for 1nm sensor wavelength shift in trhe measurement range.

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A Study on Detection of Malicious Android Apps based on LSTM and Information Gain (LSTM 및 정보이득 기반의 악성 안드로이드 앱 탐지연구)

  • Ahn, Yulim;Hong, Seungah;Kim, Jiyeon;Choi, Eunjung
    • Journal of Korea Multimedia Society
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    • v.23 no.5
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    • pp.641-649
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    • 2020
  • As the usage of mobile devices extremely increases, malicious mobile apps(applications) that target mobile users are also increasing. It is challenging to detect these malicious apps using traditional malware detection techniques due to intelligence of today's attack mechanisms. Deep learning (DL) is an alternative technique of traditional signature and rule-based anomaly detection techniques and thus have actively been used in numerous recent studies on malware detection. In order to develop DL-based defense mechanisms against intelligent malicious apps, feeding recent datasets into DL models is important. In this paper, we develop a DL-based model for detecting intelligent malicious apps using KU-CISC 2018-Android, the most up-to-date dataset consisting of benign and malicious Android apps. This dataset has hardly been addressed in other studies so far. We extract OPcode sequences from the Android apps and preprocess the OPcode sequences using an N-gram model. We then feed the preprocessed data into LSTM and apply the concept of Information Gain to improve performance of detecting malicious apps. Furthermore, we evaluate our model with numerous scenarios in order to verify the model's design and performance.

Genome Sequence of Bacillus cereus FORC_021, a Food-Borne Pathogen Isolated from a Knife at a Sashimi Restaurant

  • Chung, Han Young;Lee, Kyu-Ho;Ryu, Sangryeol;Yoon, Hyunjin;Lee, Ju-Hoon;Kim, Hyeun Bum;Kim, Heebal;Jeong, Hee Gon;Choi, Sang Ho;Kim, Bong-Soo
    • Journal of Microbiology and Biotechnology
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    • v.26 no.12
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    • pp.2030-2035
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    • 2016
  • Bacillus cereus causes food-borne illness through contaminated foods; therefore, its pathogenicity and genome sequences have been analyzed in several studies. We sequenced and analyzed B. cereus strain FORC_021 isolated from a sashimi restaurant. The genome sequence consists of 5,373,294 bp with 35.36% GC contents, 5,350 predicted CDSs, 42 rRNA genes, and 107 tRNA genes. Based on in silico DNA-DNA hybridization values, B. cereus ATCC $14579^T$ was closest to FORC_021 among the complete genome-sequenced strains. Three major enterotoxins were detected in FORC_021. Comparative genomic analysis of FORC_021 with ATCC $14579^T$ revealed that FORC_021 harbored an additional genomic region encoding virulence factors, such as putative ADP-ribosylating toxin, spore germination protein, internalin, and sortase. Furthermore, in vitro cytotoxicity testing showed that FORC_021 exhibited a high level of cytotoxicity toward INT-407 human epithelial cells. This genomic information of FORC_021 will help us to understand its pathogenesis and assist in managing food contamination.

A Study on Identifying Nursing Activities and Standard Nursing Practice Time for Developing a Neonatal Patient Classification System in Neonatal Intensive Care Unit (신생아중환자 분류도구 개발을 위한 간호활동 규명 및 표준간호시간 조사연구)

  • Ko, Bum Ja;Yu, Mi;Kang, Jin Sun;Kim, Dong Yeon;Bog, Jeong Hee;Jang, Eun Kyung;Park, Sun Ja;Oh, Sun Ja;Choi, Yun Jin
    • Journal of Korean Clinical Nursing Research
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    • v.18 no.2
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    • pp.251-263
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    • 2012
  • Purpose: It was necessary for developing a neonatal classification system based on nursing needs and direct care time. This study was, thus, aimed at identifying nursing activities and measuring the standard nursing practice time for developing a neonatal patient classification system in Neonatal Intensive Care Unit (NICU). Methods: The study was taken place in 8 general hospitals located in Seoul and Kyungi province, South Korea from Dec, 2009 to Jan, 2010. By using 'the modified Workload Management System for critical care Nurses' (WMSN), nursing categories, activities, standard time, and task frequencies were measured with direct observation. The data were analyzed by using descriptive statistics. Results: Neonatal nursing activities were categorized into 8 areas: vital signs (manual), monitoring, activity of daily living (ADL), feeding, medication, treatment and procedure, respiratory therapy, and education-emotional support. The most frequent and time-consuming area was an ADL, unlike that of adult patients. Conclusion: The findings of the study provide a foundation for developing a neonatal patient classification system in NICU. Further research is warranted to verify the reliability and validity of the instrument.

Relationship between Risk Assessment Based on Urinary Bisphenol A Concentration and Allergic Diseases in Children (어린이의 요 중 비스페놀 A 농도에 근거한 위해성 평가와 알레르기 질환과의 관련성)

  • Choi, Jihee;Hong, Soyoung;Kim, KyooSang
    • Journal of Environmental Health Sciences
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    • v.45 no.1
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    • pp.18-29
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    • 2019
  • Objectives: The purpose of this study was to examine the relationship between urinary bisphenol A concentration and allergic diseases in children. Methods: This study was conducted in Seoul, South Korea. We collected urine samples from 231 children from a single elementary school in June 2014. Among these, 69 children with urinary creatinine levels outside the normal range were excluded. Information on allergic diseases was obtained from the parents of the children. Urinary bisphenol A was analyzed using a liquid chromatography tandem mass spectrometer. Logistic regression analysis was used to determine if allergic disease was affected by urinary bisphenol A concentration. Results: Girls had a significantly higher concentration of urinary bisphenol A than did boys (p<0.05). Children of 10-12 years old had a significantly higher concentration of urinary bisphenol A than did children 7-9 years old (p<0.01). Concentration of urinary bisphenol A was increased from underweight to overweight (p<0.05). As the concentration of urinary bisphenol A was increased by $1{\mu}g/L$ or $1{\mu}g/g$ creatinine, the risks of lifetime symptoms of atopic dermatitis in children was 1.22 times (95% CI; 1.05-1.41) or 1.08 times (95% CI; 1.01-1.15). Conclusion: Concentration of urinary bisphenol A was associated with gender, age, body mass index, and allergic disease. Particularly, urinary bisphenol A concentration was associated with lifetime symptoms of atopic dermatitis. The findings of this study could contribute to the management of health effects among sensitive groups such as children.