• 제목/요약/키워드: SCO-1

검색결과 68건 처리시간 0.032초

블록 암호 SCO-1에 대한 안전성 분석 (Security Analysis on the Full-Round SCO-1)

  • 정기태;이창훈;김종성;홍석희
    • 정보보호학회논문지
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    • 제18권4호
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    • pp.27-35
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    • 2008
  • 본 논문에서는 블록 암호 SCO-1[12]에 대한 연관키 차분 공격을 소개한다. 본 논문에서 소개하는 공격은 SCO-1에 대한 첫 번째 공격이며 $2^{61}$개의 연관키 선택 암호문을 이용하여 $2^{120.59}$의 SCO-1 복호화 연산을 수행하여 SCO-1의 128-비트 비밀키를 복구한다.

The Possible Role of SCO3388, a tmrB-like Gene of Streptomyces coelicolor, in Germination and Stress Survival of Spores

  • Kwon, So-Yeon;Kwon, Hyung-Jin
    • Journal of Applied Biological Chemistry
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    • 제56권3호
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    • pp.165-170
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    • 2013
  • The SCO3388 gene from Streptomyces coelicolor is homologous to tmrB, the tunicamycin resistance gene of Bacillus subtilis. The SCO3388-inactivation strain (SY-tbl-1) was generated by replacing SCO3388 with thiostrepton resistance gene. Spores of S. coelicolor derivatives were prepared on mannitol-soy flour (MS) agar on which SY-tbl-1 displayed no significant defect in growth and development. When plated on R4 agar, spores of SYtbl-1 displayed retardation in growth and sporulation, whereas its mycelium gave rise to normal growth. Thus, SCO3388 is suggested to be involved in the dormant spore germination. Expression of SCO3388 under the ermE1 promoter restored but only partially the ability to sporulate in SY-tbl-1. Neither SY-tbl-1 nor SY-tbl-1/ermE1p-SCO3388 showed a difference in tunicamycin resistance to the wild type whereas, interestingly, the introduction of ermE1p-SCO3388 dramatically enhanced spore survival to heat and detergent treatments, suggesting that SCO3388 might play a role in the maintenance of spore cell wall integrity.

NADP+-Dependent Dehydrogenase SCO3486 and Cycloisomerase SCO3480: Key Enzymes for 3,6-Anhydro-ʟ-Galactose Catabolism in Streptomyces coelicolor A3(2)

  • Tsevelkhorloo, Maral;Kim, Sang Hoon;Kang, Dae-Kyung;Lee, Chang-Ro;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • 제31권5호
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    • pp.756-763
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    • 2021
  • Agarose is a linear polysaccharide composed of ᴅ-galactose and 3,6-anhydro-ʟ-galactose (AHG). It is a major component of the red algal cell wall and is gaining attention as an abundant marine biomass. However, the inability to ferment AHG is considered an obstacle in the large-scale use of agarose and could be addressed by understanding AHG catabolism in agarolytic microorganisms. Since AHG catabolism was uniquely confirmed in Vibrio sp. EJY3, a gram-negative marine bacterial species, we investigated AHG metabolism in Streptomyces coelicolor A3(2), an agarolytic gram-positive soil bacterium. Based on genomic data, the SCO3486 protein (492 amino acids) and the SCO3480 protein (361 amino acids) of S. coelicolor A3(2) showed identity with H2IFE7.1 (40% identity) encoding AHG dehydrogenase and H2IFX0.1 (42% identity) encoding 3,6-anhydro-ʟ-galactonate cycloisomerase, respectively, which are involved in the initial catabolism of AHG in Vibrio sp. EJY3. Thin layer chromatography and mass spectrometry of the bioconversion products catalyzed by recombinant SCO3486 and SCO3480 proteins, revealed that SCO3486 is an AHG dehydrogenase that oxidizes AHG to 3,6-anhydro-ʟ-galactonate, and SCO3480 is a 3,6-anhydro-ʟ-galactonate cycloisomerase that converts 3,6-anhydro-ʟ-galactonate to 2-keto-3-deoxygalactonate. SCO3486 showed maximum activity at pH 6.0 at 50℃, increased activity in the presence of iron ions, and activity against various aldehyde substrates, which is quite distinct from AHG-specific H2IFE7.1 in Vibrio sp. EJY3. Therefore, the catabolic pathway of AHG seems to be similar in most agar-degrading microorganisms, but the enzymes involved appear to be very diverse.

블루투스 무선 Ad-hoc망에서 ACL/SCO 패킷 데이터의 성능 (Performance of ACL/SCO Packet Data in Bluetooth Wireless Ad/hoc Network)

  • 김도균;노재성;조성언;조성준
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.29-32
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    • 2001
  • This paper has simulated the PER(Packet Error Rate), ratio of received packet and payload BER of Bluetooth system with packet types of ACL(Asynchronous Connection Less) and SCO(Synchronous Connection Oriented) link over wireless Ad-hoc environment. AWGN(Additive White Gaussian Noise) and Rayleigh fading are considered as channel model, and the analysis is based on the baseband model of Bluetooth system. In terms of PER and ratio of received packet, performance of DM1 packet is almost same as those of HV1, HV2 and HV3 packets, the performances of the other packets depend on the packet types. In terms of payload BER performance, there is no difference among HV2 packet of SCO link and DM1, DM3, DM5 packets of ACL link. Moreover, there is no difference among HV3 packet of SCO link and DM1, DM3, DM5 packets of ACL link, too.

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LuxR-Type SCO6993 Negatively Regulates Antibiotic Production at the Transcriptional Stage by Binding to Promoters of Pathway-Specific Regulatory Genes in Streptomyces coelicolor

  • Tsevelkhoroloo, Maral;Li, Xiaoqiang;Jin, Xue-Mei;Shin, Jung-Ho;Lee, Chang-Ro;Kang, Yup;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • 제32권9호
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    • pp.1134-1145
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    • 2022
  • SCO6993 (606 amino acids) in Streptomyces coelicolor belongs to the large ATP-binding regulators of the LuxR family regulators having one DNA-binding motif. Our previous findings predicted that SCO6993 may suppress the production of pigmented antibiotics, actinorhodin, and undecylprodigiosin, in S. coelicolor, resulting in the characterization of its properties at the molecular level. SCO6993-disruptant, S. coelicolor ΔSCO6993 produced excess pigments in R2YE plates as early as the third day of culture and showed 9.0-fold and 1.8-fold increased production of actinorhodin and undecylprodigiosin in R2YE broth, respectively, compared with that by the wild strain and S. coelicolor ΔSCO6993/SCO6993+. Real-time polymerase chain reaction analysis showed that the transcription of actA and actII-ORF4 in the actinorhodin biosynthetic gene cluster and that of redD and redQ in the undecylprodigiosin biosynthetic gene cluster were significantly increased by SCO6993-disruptant. Electrophoretic mobility shift assay and DNase footprinting analysis confirmed that SCO6993 protein could bind only to the promoters of pathway-specific transcriptional activator genes, actII-ORF4 and redD, and a specific palindromic sequence is essential for SCO6993 binding. Moreover, SCO6993 bound to two palindromic sequences on its promoter region. These results indicate that SCO6993 suppresses the expression of other biosynthetic genes in the cluster by repressing the transcription of actII-ORF4 and redD and consequently negatively regulating antibiotic production.

무산소조에서 온도 및 초기 C/N비에 따른 축산폐수의 탈질특성 (Denitrifications of Swine Wastewater with Various Temperature and Initial CM Ratio in Anoxic Reactor)

  • 김민호;김복현
    • 한국환경보건학회지
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    • 제29권1호
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    • pp.62-66
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    • 2003
  • The biological denitrification batch tests were conducted to optimize the operating conditions with various temperature and initial SCO $D_{Cr}$ /N $O_3$-N ratio. and the denitrification rates were analyzed various SCO $D_{Cr}$ /N $o_3$-N ratio of influent with swine wastes fermented and temperature. The finishing time of denitrification was within 15 hours, 12 hours, and 6 hours as the temperature of denitrification applied were 15$\pm$1$^{\circ}C$, 25$\pm$1$^{\circ}C$, and 31$\pm$1$^{\circ}C$, respectively. From the batch tests, denitrification rate was operated with over 3 of SCO $D_{Cr}$ /N $O_3$-N ratio. Denitrification rate was increased as the temperature of denitrification, increased such as 2.40-3.90 mg N $O_3$-N/gMLVSSㆍhr, 6.10-7.60 mgN $O_3$-N/gMLVSSㆍhr, and 14.40-15.88 mgN $O_3$-N/gMLVSSㆍhr, respectively. The denitrification rate was increased as the ratio of initial SCO $D_{Cr}$ N $O_3$-N increased. However, it was found that the suitable ratio of SCO $D_{Cr}$ /N $O_3$-N for denitrification should be considered because the ratio of mg SCO $D_{Cr}$ , consumed per mg N $O_3$-N removed varied depend on the influent SCO $D_{Cr}$ /TKN ratios.

The effect of curcumin on blood pressure and cognitive impairment in spontaneously hypertensive rats

  • Ji Young Lim;Wookyoung Kim;Ae Wha Ha
    • Nutrition Research and Practice
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    • 제17권2호
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    • pp.192-205
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    • 2023
  • BACKGROUND/OBJECTIVES: It is known that the renin-angiotensin system (RAS) in the brain could regulate cognitive functions as well as blood pressure. Inhibition of RAS for the improvement of cognitive function may be a new strategy, but studies so far have mostly reported on the effects of RAS inhibition by drugs, and there is no research on cognitive improvement through RAS inhibition of food ingredients. Therefore, this study investigated the effect of curcumin on blood pressure and cognitive function and its related mechanism in spontaneously hypertensive rat/Izm (SHR/Izm). MATERIALS/METHODS: Six-week-old SHR/Izm rats were divided into 5 groups: control group (CON), scopolamine group (SCO, drug for inducing cognitive deficits), positive control (SCO and tacrine [TAC]), curcumin 100 group (CUR100, SCO + Cur 100 mg/kg), and curcumin 200 group (CUR200, SCO + Cur 200 mg/kg). Changes in blood pressure, RAS, cholinergic system, and cognitive function were compared before and after cognitive impairment. RESULTS: The SCO group showed increased blood pressure and significantly reduced cognitive function based on the y-maze and passive avoidance test. Curcumin treatments significantly improved blood pressure and cognitive function compared with the SCO group. In both the CUR100 and CUR200 groups, the mRNA expressions of angiotensin-converting enzyme (ACE) and angiotensin II receptor type1 (AT1), as well as the concentrations of angiotensin II (Ang II) in brain tissue were significantly decreased. The mRNA expression of the muscarinic acetylcholine receptors (mAChRs) and acetylcholine (ACh) content was significantly increased, compared with the SCO group. CONCLUSIONS: The administration of curcumin improved blood pressure and cognitive function in SCO-induced hypertensive mice, indicating that the cholinergic system was improved by suppressing RAS and AT1 receptor expression and increasing the mAChR expression.

브랜드 로고 기호의 의미작용과 커뮤니케이션 분석 체계의 제안과 활용:소셜 미디어 브랜드 로고를 중심으로 (Design and use of the Signification and Communication Analysis Frame for the Brand Logo Sign: based on the Social Media Brands)

  • 권보연
    • 한국콘텐츠학회논문지
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    • 제11권6호
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    • pp.76-89
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    • 2011
  • 브랜드 로고는 상품과 서비스의 경쟁이 의미적으로 시작되는 출발점인 바, 로고 기호의 의미작용과 커뮤니케이션에 대한 분석은 브랜드 간 차이와 변별 요소의 발견에 기여할 수 있다. 이에 본 논문은 브랜드로고 기호작용에 대하여 총체적이고 일관성 있는 판독을 위한 분석 체계인 'SCoL' (Analysis frame of signification and communication for the brand logo, SCoL, 스콜) 를 개발하고, 이를 서비스의 초기 경쟁에 있어 로고 기호의 의존도가 높은 소셜 미디어 브랜드 로고 분석에 적용함으로써 제안의 타당성을 증명하고자 한다. SCoL은 브랜드 로고 기호의 4가지 형식 구성 요소를 토대로 퍼스의 도상, 지표, 상징을 통한 1단계 의미 작용 분석에 이어 2단계 분석으로 야콥슨의 이론을 적용하여 커뮤니케이션 기능을 해석할 수 있도록 고안되었다. SCoL 프레임을 적용하여 소셜 미디어 브랜드 로고 기호를 분석한 결과 소셜 미디어 브랜드들은 기호작용을 통해 고유한 의미 영역을 구축하고 있었으며, 또한 서로 다른 커뮤니케이션 기능에 의존하여 브랜드의 의미를 전달하고 있음을 발견하였다. SCoL은 분석 과정에서 브랜드 로고 기호의 구성 요소에 대한 판독 단위를 제공하여 기호학적 관점에서 로고의 의미 작용과 커뮤니케이션 기능 해석을 위한 유효한 분석 도구로 역할 하였다.