• 제목/요약/키워드: RIF

검색결과 85건 처리시간 0.024초

Understanding Rifampicin Resistance in Tuberculosis through a Computational Approach

  • Kumar, Satish;Jena, Lingaraja
    • Genomics & Informatics
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    • 제12권4호
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    • pp.276-282
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    • 2014
  • The disease tuberculosis, caused by Mycobacterium tuberculosis (MTB), remains a major cause of morbidity and mortality in developing countries. The evolution of drug-resistant tuberculosis causes a foremost threat to global health. Most drug-resistant MTB clinical strains are showing resistance to isoniazid and rifampicin (RIF), the frontline anti-tuberculosis drugs. Mutation in rpoB, the beta subunit of DNA-directed RNA polymerase of MTB, is reported to be a major cause of RIF resistance. Amongst mutations in the well-defined 81-base-pair central region of the rpoB gene, mutation at codon 450 (S450L) and 445 (H445Y) is mainly associated with RIF resistance. In this study, we modeled two resistant mutants of rpoB (S450L and H445Y) using Modeller9v10 and performed a docking analysis with RIF using AutoDock4.2 and compared the docking results of these mutants with the wild-type rpoB. The docking results revealed that RIF more effectively inhibited the wild-type rpoB with low binding energy than rpoB mutants. The rpoB mutants interacted with RIF with positive binding energy, revealing the incapableness of RIF inhibition and thus showing resistance. Subsequently, this was verified by molecular dynamics simulations. This in silico evidence may help us understand RIF resistance in rpoB mutant strains.

RIF 추론에 의한 RDF 권한 충돌 문제 분석 (An Analysis of the RDF Authorization Conflict Problem by RIF Inference)

  • 김재훈;이재근;강일용;이용우;박석
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(C)
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    • pp.1-3
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    • 2012
  • RIF(Rule Interchange Format)는 시맨틱 웹의 구조중 규칙 계층을 담당하며 기존에 사용되고 있는 여러 상이한 규칙 언어들 간의 호환을 위한 표준 규칙 언어라고 할 수 있다. RIF는 W3C에서 승인되었다. 시맨틱웹을 위한 표준 온톨로지 언어로는 RDF와 OWL이 있으며, 최근 RDF 데이터에 대한 접근제어 (Access Control) 메커니즘과 관련하여 일부 학술적 연구가 수행되었다. 본 논문에서는 RDF 데이터와 결합될 수 있는 RIF 추론 규칙에 대해 이미 제안한 RDF 접근제어 메커니즘을 확장하고자 한다. RDF 데이터에 대해 명세된 접근 권한은 RIF 추론에 의하여 권한 충돌이 발생할 수 있고, 그로 인해 접근 권한은 허용되지 않을 수 있다. 본 논문에서는 어떤 조건에서 이러한 RIF 추론에 의한 권한 충돌이 발생하는 지를 분석하며, 이미 제안한 그래프 레이블링을 사용하는 충돌 발견 방법이 RIF 추론과 관련하여서도 효율적임을 보인다. 실험에서는 제안된 방법이, 비록 포함관계 추론에 특화 되었지만, Chase 알고리즘에 기반한 다른 연구에서의 방법보다 발견 시간을 크게 감소시킴을 보인다.

상세 화학 반응 모델 및 RIF 모델을 이용한 디젤 분무의 자발화 과정 해석 (Numerical Simulation of Auto-ignition Process of Diesel Sprays Using Detailed Chemistry and Representative Flamelet Model)

  • 유용욱;김성구;김용모;손정락
    • 한국분무공학회지
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    • 제5권2호
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    • pp.61-67
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    • 2000
  • The interaction between chemistry and turbulence is treated by employing the Representative Interactive Flamelet (RIF) Model. The detailed chemistry of 114 elementary steps and 44 chemical species is adopted for the n-heptane/air reaction. In order to account for the spatial inhomogeneity of the scalar dissipation rate, the multi-RIF is used. The effect of the number of RIF on ignition delay is discussed in detail. Numerical results indicate that the present RIF approach successfully predicts the ignition delay time as well as the essential features of a spray auto-ignition process.

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Design and analysis of RIF scheme to improve the CFD efficiency of rod-type PWR core

  • Chen, Guangliang;Qian, Hao;Li, Lei;Yu, Yang;Zhang, Zhijian;Tian, Zhaofei;Li, Xiaochang
    • Nuclear Engineering and Technology
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    • 제53권10호
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    • pp.3171-3181
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    • 2021
  • This research serves to advance the development of engineering computational fluid dynamics (CFD) computing efficiency for the analysis of pressurized water reactor (PWR) core using rod-type fuel assemblies with mixing vanes (one kind of typical PWR core). In this research, a CFD scheme based on the reconstruction of the initial fine flow field (RIF CFD scheme) is proposed and analyzed. The RIF scheme is based on the quantitative regulation of flow velocities in the rod-type PWR core and the principle that the CFD computing efficiency can be improved greatly by a perfect initialization. In this paper, it is discovered that the RIF scheme can significantly improve the computing efficiency of the CFD computation for the rod-type PWR core. Furthermore, the RIF scheme also can reduce the computing resources needed for effective data storage of the large fluid domain in a rod-type PWR core. Moreover, a flow-ranking RIF CFD scheme is also designed based on the ranking of the flow rate, which enhances the utilization of the flow field with a closed flow rate to reconstruct the fine flow field. The flow-ranking RIF CFD scheme also proved to be very effective in improving the CFD efficiency for the rod-type PWR core.

체외수정에서 반복 착상 실패(RIF) 환자 침치료 최근 연구 동향 (Recent Research Trends of Acupuncture Treatment for Recurrent Implantation Failure (RIF) Patients in In Vitro Fertilization)

  • 조세연;김승규;황덕상;이진무;장준복;이창훈
    • 대한한방부인과학회지
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    • 제37권2호
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    • pp.120-134
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    • 2024
  • Objectives: This research aimed at investigating the trends of acupuncture treatment for Recurrent Implantation Failure (RIF) patients in IVF. Methods: Studies were searched from PubMed, Cochrane Library, EMBASE, CNKI up to April 2024. Terms as 'Implantation failure', 'Recurrent implantation failure', 'Repeated implantation failure', 'RIF' and 'Acupuncture', 'Electroacupuncture', 'Needling' were used. Results: Of 136 screened, 10 studies are selected and analyzed. Studies were conducted using manual acupuncture and electroacupuncture. The results showed that acupuncture (electroacupuncture) treatment for RIF patients is effective in improving clinical pregnancy rate, endometrial blood flow, uterus morphology, endometrium thickness. The most frequently used acupoints were 三陰交 (SP6) and 子宮 (EX-CA1). Conclusions: Included studies showed that acupuncture (electroacupuncture) might have effect on RIF. Further research and meta-analysis should be conducted to verify its therapeutic mechanisms and safety.

TRANSIENT FLAMELET MODELING FOR COMBUSTION PROCESSES OF HSDI DIESEL ENGINES

  • Kim, H.J.;Kang, S.M.;Kim, Y.M.;Lee, J.H.;Lee, J.K.
    • International Journal of Automotive Technology
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    • 제7권2호
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    • pp.129-137
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    • 2006
  • The representative interactive flamelet(RIF) concept has been applied to numerically simulate the combustion processes and pollutant formation in the HSDI diesel engine. In order to account for the spatial inhomogeneity of the scalar dissipation rate, the eulerian particle flamelet model using the multiple flamelets has been employed. The vaporization effects on turbulence-chemistry interaction are included in the present RIF procedure. the results of numerical modeling using the rif concept are compared with experimental data and with numerical results of the widely-used ad-hoc combustion model. Numerical results indicate that the rif approach including the vaporization effect on turbulent spray combustion process successfully predicts the ignition delay characteristics as well as the pollutant formation in the HSDI diesel engines.

Corynebacterium 세균의 이종간 원형질체 융합에 의한 재조합주의 유전학적 분석과 L-glutamate와 L-glutamine 생성 (Genetic Analysis of Recombinants by Interspecific Protoplast Fusion of Coryneform Bacteria and Their L-glutamate & L-glutamine Production)

  • 백선영;이혜경;최순영;김종욱;이세배;임번삼;민경희
    • 한국미생물·생명공학회지
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    • 제18권3호
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    • pp.296-300
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    • 1990
  • 자외선 조사와 NTG를 처리하여 Brevibacterium flavum 10AHR(arg his $Rif^r$)과 Corynebacterium glutamicum 11TS(trp $Sm^r$의 돌연변이주를 분리하였다. B.flavum 10AHR과 C.glutamicum 11TS를 300$\mu g$/ml의 lysozyme으로 18시간 처리하여 원형질체를 형성하고, 융합시 30의 PEG 6,000으로 처리하였을 때 가장 높은$3.7\times 10^{-6}$의 융합빈도를 나타내었다.

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Comparative Performance of Line Probe Assay (Version 2) and Xpert MTB/RIF Assay for Early Diagnosis of Rifampicin-Resistant Pulmonary Tuberculosis

  • Yadav, Raj Narayan;Singh, Binit Kumar;Sharma, Rohini;Chaubey, Jigyasa;Sinha, Sanjeev;Jorwal, Pankaj
    • Tuberculosis and Respiratory Diseases
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    • 제84권3호
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    • pp.237-244
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    • 2021
  • Background: The emergence of drug-resistant tuberculosis (TB), is a major menace to cast off TB worldwide. Line probe assay (LPA; GenoType MTBDRplus ver. 2) and Xpert MTB/RIF assays are two rapid molecular TB detection/diagnostic tests. To compare the performance of LPA and Xpert MTB/RIF assay for early diagnosis of rifampicin-resistant (RR) TB in acid-fast bacillus (AFB) smear-positive and negative sputum samples. Methods: A total 576 presumptive AFB patients were selected and subjected to AFB microscopy, Xpert MTB/RIF assay and recent version of LPA (GenoType MTBDRplus assay version 2) tests directly on sputum samples. Results were compared with phenotypic culture and drug susceptibility testing (DST). DNA sequencing was performed with rpoB gene for samples with discordant rifampicin susceptibility results. Results: Among culture-positive samples, Xpert MTB/RIF assay detected Mycobacterium tuberculosis (Mtb) in 97.3% (364/374) of AFB smear-positive samples and 76.5% (13/17) among smear-negative samples, and the corresponding values for LPA test (valid results with Mtb control band) were 97.9% (366/374) and 58.8% (10/17), respectively. For detection of RR among Mtb positive molecular results, the sensitivity of Xpert MTB/RIF assay and LPA (after resolving discordant phenotypic DST results with DNA sequencing) were found to be 96% and 99%, respectively. Whereas, specificity of both test for detecting RR were found to be 99%. Conclusion: We conclude that although Xpert MTB/RIF assay is comparatively superior to LPA in detecting Mtb among AFB smear-negative pulmonary TB. However, both tests are equally efficient in early diagnosis of AFB smear-positive presumptive RR-TB patients.

검사방법(檢査方法)에 따르는 항균제감수성(抗菌劑感受性)의 비교(比較) (Comparative Antimicrobial Susceptibility by the Methods of Test)

  • 박동춘;전도기
    • 대한미생물학회지
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    • 제13권1호
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    • pp.43-48
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    • 1978
  • 항균제내성(抗菌劑耐性)인 Salmonella typhi를 공시(供試)하여 chloramphenicol(Cm), tetracycline(Tc), ampicillin(Ap), kanamycin(Km) 및 rifampicin(Rif)의 항균작용(抗菌作用)을 한천평판희석법(寒天平板稀釋法)(평판법(平板法))과 broth 희석법(稀釋法)(broth법(法))으로 비교(比較)하였다. 공시균(供試菌)의 최소발육저지농도(最少發育沮止濃度)(MIC)를 보면 Cm, Tc 및 Rif에 있어서는 평판법(平板法)과 broth법(法) 사이에 유의(留意)할만한 차이(差異)는 없었으나 Km에 있어서는 broth법(法)의 MIC가 평판법(平板法)보다 높은 것이 약(約) 반수(半數)있었고 Ap에 있어서도 소수(少數) 있었다. Cm과 Rif는 대부분(大部分)의 공시균(供試菌)에 대(對)하여 정균적(靜菌的)으로 작용(作用)하였으나 Tc, Ap 및 Km은 살균적(殺菌的)으로 작용(作用)하였고 그 작용(作用)은 균주(菌株)에 따라 차이(差異)가 있었다.

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자극의 구별성과 부분 인출이 기억에 미치는 영향 (The Effect of Distinctiveness of stimulus and Partial Retrieval on Memory)

  • 정윤재
    • 인지과학
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    • 제30권1호
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    • pp.31-50
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    • 2019
  • 본 연구는 인출 연습 범주 내 비 인출 연습 항목의 지각적, 정서적, 의미적 구별성이 인출 유도 망각(retrieval induced forgetting; RIF)에 미치는 영향을 알아보기 위해 수행되었다. 실험 1은 인출 유도 망각 실험 패러다임에 적합한 범주와 범주 내 항목을 구성하고, 인출 연습 범주 내 비 인출 연습 항목의 지각적 구별성이 인출 유도 망각에 미치는 영향을 알아보기 위해 수행되었다. 6개의 범주와 각 범주 당 6개의 단어들로 이루어진 목록이 사용되었다. 통제조건에서는 지시문을 포함하여 범주명과 범주 내 항목 등 모든 자극이 고딕체의 검은색으로 제시었다. 반면 지각적 구별성 조건에서는 지시문과 범주명, 범주 내 항목의 절반은 검은색 고딕체로 제시되었고, 나머지 범주 내 항목의 절반은 붉은색의 궁서체로 제시되었다. 그 결과 통제집단 뿐만 아니라 지각적 구별성 조건 모두 인출 유도 망각이 관찰되었다. 실험 2는 부적정서의 구별성과 의미적 구별성이 인출 유도 망각에 미치는 영향을 알아보기 위해 수행되었다. 부적정서의 구별성은 범주 내 항목의 절반에 부적 형용사를 덧붙이는 방식으로 조작되었다. 의미적 구별성은 범주 내 항목의 절반에 의미적으로 특이한 형용사를 덧붙이는 방식으로 조작되었다. 중성 조건은 모든 범주 내 항목에 중성적인 형용사를 덧붙이는 방식으로 조작되었다. 그 결과 중성 조건에서는 인출유도망각이 발생된 반면 부적정서 구별성 조건과 의미적 구별성 조건 모두 인출 유도 망각이 발생되지 않았다. 이러한 결과는 구별성이 범주와 범주 내 항목간의 연합관계 안에서 작용될 때만 인출 유도 망각이 발생되지 않을 가능성을 제안한다.