• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.1043-1048
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• 2012

The COPS3 gene has stimulating effect on cell proliferation and progression of osteosarcomas and related cells. However, the features of COPS3 and its potential application as a therapeutic target in other cancers has not yet been studied. In this study, therefore, the effect of COPS3 silencing via COPS3 siRNA on lung cancer cell proliferation was examined. Expression levels of COPS3 gene in COPS3 siRNA infected cells and control siRNA infected cells were compared with real time PCR and Western blot analysis. Cell proliferation levels were comprehensively analyzed by MTT, BrdU incorporationy, and colony formation assays. For mechanistic assessment the effects of COPS3 silencing on cell cycle and apoptosis were analyzed using flow cytometry. Results showed that successful silencing of the COPS3 gene at both translational and transcriptional levels significantly reduced the proliferation and colony formation by lung cancer cells (p<0.01). Flow cytometry showed cell cycle arrest in the G0/G1 phase after COPS3 silencing, and more importantly, apoptosis was induced as a result of COPS3 knockdown, which negatively affected cell survival. Therefore, these results provide another piece of important evidence that the COPS3 gene expressed in lung cancer cells may play a critical role in stimulating proliferation. Down-regulation of COPS3 could significantly inhibit lung cancer cell growth, which was most likely mediated via induction of cell cycle arrest in G0/G1 phase and apoptosis.

• Journal of the Korean Applied Science and Technology
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• v.40 no.5
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• pp.1163-1175
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• 2023

Cholesterol is prone to oxidation, which results in the formation of cholesterol oxidation products (COPs). This occurs because it is a monounsaturated lipid with a double bond on C-5 position. Cholesterol in foods is mostly non-enzymatically oxidized by reactive oxygen species (ROS)-mediated auto-oxidative reaction. The COPs are found in many common foods of animal-origin and are formed during their manufacture process. The formation of COPs is mainly related to the temperature and the heating time the food is processed, storage condition, light exposure and level of activator present such as free radical. The level of COPs in processed foods could reach up to 1-10 % of the total cholesterol depending on the foods. The most predominant COPs in foods including meat, eggs, dairy products as well as other foods of animal origin were 7-ketocholesterol, 7 α-hydroxycholesterol (7α-OH), 7β-hydroxycholesterol (7β-OH), 5,6α-epoxycholesterol (5,6α-EP), 5,6β-epoxycholesterol (5,6β-EP), 25-hydoxycholesterol (25-OH), 20-hydroxycholesterol (20-OH) and cholestanetriol (triol). They are mainly formed non-enzymatically by cholesterol autoxidation. The COPs are known to be potentially more hazardous to human health than pure cholesterol. The procedure to block cholesterol oxidation in foods should be similar to that of lipid oxidation inhibition since both cholesterol and lipid oxidation go through the same free radical mechanism. The formation of COPs in foods can be stopped by decreasing heating time and temperature, controlling storage condition as well as adding antioxidants into food products. This review aims to present, discuss and respond to articles and studies published on the topics of the formation and inhibition of COPs in foods and key factors that might affect cholesterol oxidation. This review may be used as a basic guide to control the formation of COPs in the food industry.

• Journal of Adhesion and Interface
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• v.15 no.3
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• pp.93-99
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• 2014

Monodisperse poly[styrene-co-(COPS-I)] latices in the size range of 165~550nm were successfully prepared by soap-free emulsion polymerization with various polymerization conditions (Styrene, COPS-I, KPS, DVB concentrations and polymerization temperature). In general, the COPS-I and KPS, DVB concentrations and polymerization temperature were closely related to the polymerization rate and the number of particles, molecular weight, and zeta potential. The polymerization rate and zeta potential increased, but molecular weight decreased, with increasing in the number of particles.

• Bulletin of the Korean Mathematical Society
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• v.57 no.1
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• pp.127-131
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• 2020

We discuss two unrelated topics regarding Cops and Robbers, a well-known pursuit-evasion game played on a simple graph. First, we address a recent question of Breen et al. and prove the PSPACE-completeness of the cop throttling number, that is, the minimal possible sum of the number k of cops and the number capt(k) of moves that the robber can survive against k cops under the optimal play of both sides. Secondly, we revisit a teleporting version of the game due to Wagner; we disprove one of his conjectures and suggest a new related research problem.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05b
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• pp.1453-1456
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• 2003

인터넷의 발달로 인하여 기존 전화망을 인터넷 망으로 적은 비용으로 사용하고자 VoIP 가 연구되기 시작하였다. VoIP 의 기존전화망과의 품질의 차이에도 불구하고 대폭적인 통화비용의 절감과 다양한 이점으로 많은 연구가 되고 있다. 이에 통화품질의 향상을 위하여 QoS에 대한 연구가 활발히 진행되고 있다. 여기서는 QoS를 지원하는 Q-SIP 서버와 Policy Based 의 COPS 를 이용하여 Pre-COPS update message 와 Reservation COPS cache로 정책결정과 QoS를 지원하고자 한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.5
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• pp.1-6
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• 2009

MANET(Mobile Ad-hoc NETwork), a network characterized that its moving nodes freely constructs Network topology, has other different characteristics. Because Policy based Network Management in MANET guarantees QoS between nodes, it is essential in applied areas like VANET which targets safety and convenience. In this paper, we use COPS-PR which is appropriate Policy Exchange Protocol for MANET, and implement DiffServ-based QoS in the real networks and experiment its capability.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.61-62
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• 2015

본 논문에서는 XNA Framework 기반의 모바일 게임 Cops VS Gangster를 설계하고 구현한다. 이 모바일 게임은 단순 피하기 게임 장르로 배경은 도로, 아파트 단지 등 생활 주변과 유사하도록 구현하였으며, 경찰차( Cops)는 오토바이(Gangster)의 주행을 피하면서 전진한다. 경찰차가 라이프(Heart)와 접촉하면 점수(Score)를 획득하고, 오토바이와 접촉하면 게임이 종료된다.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.433-441
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• 2018

The objective of present study was to investigate the effect of cooking and their combinations with re-heating methods on the formation of cholesterol oxidation products (COPs) in stored chicken thigh meat. Pan roasting, steaming, oven grilling, charcoal grilling, and microwaving were used for cooking. Re-heating of samples was done using the same cooking methods or microwaving after 3 and 6 d of refrigerated storage. Cooking and re-heating resulted in reduction of crude fat and cholesterol contents of chicken thigh meat depending on storage period before re-heating. Cooking and storage period had no influence on the total amount of COPs. The highest total amount of COPs was observed in meat samples cooked by steaming and reheated by microwaving after 6 d of storage, which showed similar value to raw chicken meat stored for 6 days. However, different re-heating methods formed different types of COPs depending on storage period before re-heating. The high amount (p<0.05) of 25-hydroxycholesterol or ${\alpha}-epoxide$ was detected in meat samples reheated by steaming or microwaving at 3 or 6 d of storage after steamed cooking, respectively. As a result, the combination of steaming and re-heating with microwaving could increase the total amount of COPs in chicken thigh meat and different cooking/re-heating methods could form different types of COPs, even though no significant difference in the total amount of COPs depending on storage period.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2787-2794
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• 2013

Cholesterol and cholesterol oxidation products (COPs) may accumulate in foods of animal origin during processing or storage. An effective and sensitive analytical method was developed by increasing the UV absorption of compounds through derivatization by attaching a chromophore to the functional groups of cholesterols (cholesterol, 20-hydroxycholesterol, 7-ketocholesterol, cholestane-$3{\beta}$-$5{\alpha}$-$6{\beta}$-triol, 25-hydroxycholesterol, and $5,6{\alpha}$-epoxycholesterol). The influences of the reaction time, volume of reaction solvent, amounts of derivatizing reagent, and extraction solvents were investigated, as they may influence the reaction and extraction yield. The derivatized COPs were analyzed simultaneously on a C18 column (2.1 mm i.d. ${\times}$ 100 mm length, $3.5{\mu}m$ particle size) using a gradient elution with water and acetonitrile. The derivatized COPs showed increased sensitivity and selectivity in HPLC/UV-Vis. The LOD and LOQ were in the concentration ranges of 0.018-0.55 mg/kg and 0.059-1.84 mg/kg from the powdered milk. And the accuracy and precision were 78.1-116.7% and 1.1-9.9%, respectively.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10a
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• pp.784-786
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• 2001

인터넷의 성장과 더불어 네트워크를 통한 침입의 가능성이 증가됨에 따라 시스템이나 네트워크 침입을 탐지하고 대응할 수 있는 기술들이 필요하게 되었다. 이와 관련하여 많은 연구가 이루어지고 있으나, 보안정책정보 전달을 위한 방법에 대해서는 아직까지 활발히 이루어지고 있지 않는 실정이다. 본 논문에서는 기존의 정책 전달 프로토콜인 COPS 프로토콜을 확장, 수정하여 보안정책 정보(Security policy Information)를 전달할 수 있는 COFS- SECURITY프로토콜에 대해 기술한다.