• 한국콘텐츠학회논문지
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• 제15권12호
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• pp.18-23
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• 2015

SIP 등록 취소 공격은 공격자가 정상적 SIP UA의 REGISTER 메시지를 간단히 위장함으로써 야기되지만, 그 영향력은 매우 크다. 본 논문에서는 등록 서버가 등록 취소 REGISTER 메시지를 수신하는 즉시 위치 서버로부터 바인딩을 제거함으로써 등록을 취소하는 대신에, 일정 기간을 지연한 후에 취소하게 함으로서 등록 취소 공격을 식별하고 방어하게 해주는 새로운 방법을 제안한다. 따라서 본 논문에서 제안한 이 기법은 추가적인 암호화나 인증 과정들의 오버헤드 없이 SIP 등록 취소 공격에 대응하는 안전한 SIP 환경을 구축할 수 있게 한다.

• 생명과학회지
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• 제5권1호
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• pp.26-32
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• 1995

The antimutagenic effects of insoluble dietary fibers(IDF) extracted from some green-yellow vegetables(kale, carrot, spinach, broccoli and soybean sprout) and soybean by binding the carcinogens of MeIQ (2-amino-3,4- dimethyl-imidazo(4,5-f) quinoline) and Trp-P-2(3-amino-1-methyl-5H-pyrido[4,3-b] indole) in Salmonella tylhimirium TA100 and TA98 were studied. All of the insoluble dietary fiber samples which binded MeIQ exhibited high antimutagenic effects by removing the mutagen. Among the samples, IDFs from kale and soybean showed strong binding capacity fo the carcinogen and revealed about 90% of the antimutagenic activity. the IDF samples showed somewhat lower binding capacity to the Trp-p-2. The lignin which extracted from kale, soybean and carrot, and the cellulose strongly removed the mutagenicity of MeIQ by the binding. Among the samples, the level of lignin in kale revealed the highest(about 10%), and it seemed that the higher content of lignin in kale is one of the reasons to increase its antimutagenic effect.

• The Korean Journal of Ecology
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• 제26권5호
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• pp.263-266
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• 2003

This research investigated the process of removing cadmium and tested the detoxification mechanism of the cadmium-binding peptide (Cd-BP) from Rumex crispus. Phytochelatin-like cadmium-binding peptide (PC-Cd-BP) of Rumex crispus was purified and identified. Rumex crispus was exposed to 4.3 mg Cd/L for seven days. Heat-treated supernatant fraction taken by root tissues showed traces of PC-Cd-BP An analysis of the material through Gel-filteration chromatography on the Sephadex G-75 column showed two symmetrical Cd-BP peaks. The major peak with the smaller molecular weight was further purified by $C_{18}$ reverse-phase HPLC to produce apparent homogeneity. The amino acid composition of Cd-BP from Rumex crispus included cysteine (22.6%), glutamate and glutamate acid (20%), and glycine (12%). It was similar the amino acid composition of most PC. The molecular weight of the purified peptide was determined at 568-706 Da by MALDI-TOF MS. Therefore, the Cd-BP of Rumex crispus was PC-Cd-BP consisting of isopeptides.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1088-1097
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• 2021

Grouper nervous necrosis virus (GNNV) infection causes mass grouper mortality, leading to substantial economic loss in Taiwan. Traditional methods of controlling GNNV infections involve the challenge of controlling disinfectant doses; low doses are ineffective, whereas high doses may cause environmental damage. Identifying potential methods to safely control GNNV infection to prevent viral outbreaks is essential. We engineered a virus-binding bacterium expressing a myxovirus resistance (Mx) protein on its surface for GNNV removal from phosphate-buffered saline (PBS), thus increasing the survival of grouper fin (GF-1) cells. We fused the grouper Mx protein (which recognizes and binds to the coat protein of GNNV) to the C-terminus of outer membrane lipoprotein A (lpp-Mx) and to the N-terminus of a bacterial autotransporter adhesin (Mx-AIDA); these constructs were expressed on the surfaces of Escherichia coli BL21 (BL21/lpp-Mx and BL21/Mx-AIDA). We examined bacterial surface expression capacity and GNNV binding activity through enzyme-linked immunosorbent assay; we also evaluated the GNNV removal efficacy of the bacteria and viral cytotoxicity after bacterial adsorption treatment. Although both constructs were successfully expressed, only BL21/lpp-Mx exhibited GNNV binding activity; BL21/lpp-Mx cells removed GNNV and protected GF-1 cells from GNNV infection more efficiently. Moreover, salinity affected the GNNV removal efficacy of BL21/lpp-Mx. Thus, our GNNV-binding bacterium is an efficient microparticle for removing GNNV from 10‰ brackish water and for preventing GNNV infection in groupers.

• BMB Reports
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• 제34권6호
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• pp.489-495
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• 2001

DNA damage by UV and environmental agents are the major cause of genomic instability that needs to be repaired, otherwise it give rise to cancer. Accordingly, mammalian cells operate several DNA repair pathways that are not only responsible for identifying various types of DNA damage but also involved in removing DNA damage. In mammals, nucleotide excision repair (NER) machinery is responsible for most, if not all, of the bulky adducts caused by UV and chemical agents. Although most of the proteins involved in NER pathway have been identified, only recently have we begun to gain some insight into the mechanism by which proteins recognize damaged DNA. Binding of Xeroderma pigmentosum group C protein (XPC)-hHR23B complex to damaged DNA is the initial damage recognition step in NER, which leads to the recruitment of XPA and RPA to form a damage recognition complex. Formation of damage recognition complex not only stabilizes low affinity binding of XPA to the damaged DNA, but also induces structural distortion, both of which are likely necessary for the recruitment of TFIIH and two structure-specific endonucleases for dual incision.

• 반도체디스플레이기술학회지
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• 제15권4호
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• pp.92-96
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• 2016

Although deregistration attack is caused by simple spoofing the REGISTER message of a legitimate SIP UA, its impact is serious. The root cause of this attack is based on the fact that RFC 3261 allows the UA to remove the binding from the Location Server. In this paper, we propose a simple protection method to allow Registrar or Location Server just to ignore deregistration messages. We also show that this method works well by analyzing the process of registration and deregistration. Without any additional overhead such as an encryption or authentication, this method is able to establish a secure SIP environment efficiently protecting against the deregistration attack.

• Journal of Microbiology and Biotechnology
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• 제19권12호
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• pp.1612-1616
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• 2009

Isoflavonoids are a class of phytoestrogens. Isoflavonone synthase (IFS) is responsible for the conversion of naringenin to genistein. IFS is a cytochrome P450 (CYP), and requires cytochrome P450 reductase (CPR) for its activity. Additionally, the majority of cytochrome P450s harbor a membrane binding domain, making them difficult to express in Escherichia coli. In order to resolve these issues, we constructed an inframe fusion of the IFS from red clover (RCIFS) and CPR from rice (RCPR) after removing the membrane binding domain from RCIFS and RCPR. The resultant fusion gene, RCIFS-RCPR, was expressed in E. coli. The conversion of naringenin into genistein was confirmed using this E. coli transformant. Following the optimization of the medium and cell density for biotransformation, $60\;{\mu}M$ of genistein could be generated from $80\;{\mu}M$ of naringenin. This fusion protein approach may be applicable to the expression of other P450s in E. coli.

• 한국정보과학회논문지:시스템및이론
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• 제29권9호
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• pp.493-502
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• 2002

다중 컴퓨터 네트워크의 고장 감내에 대한 대표적인 결정적 척도로 연결도와 에지 연결도가 있다. 연결도나 에지 연결도는 어떤 정점 분리 집합이나 에지 분리 집합을 제거했을 때 남은 그래프의 형태를 고려하지 않는다는 문제가 있다. 이러한 단점을 보완하기 위해서 superconnectivity, toughness, scattering number, vertex-integrity, binding number, restricted connectivity와 같은 일반화된 연결성 척도들이 함께 사용된다. 이 논문에서는 재귀원형군과 하이퍼큐브의 고장 감내에 대한 이러한 결정적 척도를 분석하고, 고장 감내 측면에서 비교한다.

• 대한한의학방제학회지
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• 제24권3호
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• pp.195-211
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• 2016

Objectives : The purpose of this study was to investigate the interpretation of the Daeseunggi-tang(DST) in order to obtain the evidence for clinical applications.Methods and Results : We have analyzed the interpretation on the DST through translations and comparisons based on classic books about the oriental medical prescriptions.Conclusion : 1. 'Dae(大)' in DST means 'strong symptoms' or 'strong efficacy'. 'Seung(承)' in DST means 'smooth (順)', 'attach(連)' and 'serve(奉)'. 2. The main pathogenesis of DST's syndrome are heat binding(熱結)·qi stagnation(氣滯). 3. The main areas where disease pattern of DST is 'Yang brightness(陽明)'. It is also associated with 'Lesser yin (少陰)', 'Qi aspect(氣分)·Blood aspect(血分)' and 'Triple Energizer(三焦)'. 4. Laxative the Rhei Radix et Rhizoma(大黃) is sovereign medicinal(君藥) of DST, because of removing the heat binding(熱結) and the heat that spread throughout the body.

• 한국건축시공학회지
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• 제16권3호
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• pp.219-227
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• 2016

본 연구에서는 염해에 열화작용을 일으키는 염소이온을 고정하기 위한 방안으로 이온교환능력과 흡착능력이 우수하다고 알려진 층상이중수산화물(LDHs)을 활용하였다. 실험에 앞서 두 종류의 LDHs(Mg/Ca)를 공침법을 사용하여 합성하였고, 합성된 고형물을 활용하여 수용액내에서 실험적 연구를 진행하였다. 일반적 합성법인 공침법으로 기존문헌의 입증된 나노 입자의 LDHs를 제조 할 수 있었으며 이는 건축재료로써의 적용에 앞서 간단한 제조방법만으로도 제조가 가능하다는 긍정적인 효과로 볼 수 있다. 또한, 이온교환시간 15분내에서는 Mg체계가 고정속도가 빨랐으나, 그 후의 시간에서는 최대 4시간까지 Ca체계의 고정량이 우수하였다. 임계치 $1.2kg/m^3$의 경우 0.5 g당 Mg/Ca은 각각 0.0035g, 0.0015g의 염소이온을 고정하였다. 또한, 효과가 우수했던 이온교환된 Ca체계를 XRD 분석한 결과 층간에 삽입한 $NO_3$가 용출되고 염소이온이 치환되었음을 알 수 있었다. 시멘트계의 적용시 Mg체계보다 Ca체계가 우수한 고정효과를 기대 할 수 있다고 판단되며, 향후 연구에서는 본 연구에 결과를 바탕으로 시멘트계 재료에서의 염소이온 고정효율을 평가하고자 한다.