• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.2000-2003
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• 2006

A gene (GenBank AF096282) coding for a $\alpha$-glucosidase (TcaAG, EC 3.2.1.20) from Thermus caldophilus GK24 was expressed in Saccharomyces cerevisiae, a generally recognized as safe (GRAS) host. The thermostable $\alpha$-glucosidase was produced inside of the GRAS host at 0.04 unit/mg-dry cell by the constitutively expressing ADH1 promoter and at 1.2 unit/mg-dry cell by the inductively expressing GALl0 promoter, respectively. No $\alpha$-glucosidase activities were found in the medium when the MF-alpha signal sequence from S. cerevisiae or $\alpha$-amylase signal sequence from Aspergillus oryzae were fused before the $\alpha$-glucosidase gene for the secretion.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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• pp.167-170
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• 1995

An frequency modulated (FM) DANTE pulse sequence generates a quadratic phase toward the transverse of image by an FM RF pulse. In the image of a serious susceptibility effect, the phase due to the difference of the susceptibility in the pixel occurs susceptibility error which arise signal loss. But the signal loss due to the susceptibility effect in the pixel is reduced when the quadratic phase adds in the pixel. In this paper, we have generated a quadratic function toward the transverse (X-Y) using FM DANTE sequence and the susceptibility effect is reduced in the gradient echo (GE) imaging. Computer simulation and experimental results is obtained by using a whole-body KAIS 2.0T NMR system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.107.5-107
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• 2001

In this report, as the active position measurement system, a new method for two-dimensional position measurement system using a concept of semi-open type signal field has proposed. The feature of this system is realizing a position measurement only by scanning the encoded laser beams from scanning points to a measurement field, and observed it. First, both system configuration and encoding method are considered concretely, and M-sequence signal is selected for encoding. Next system design is performed to realize the theoretical measurement accuracy, and applied to a position measurement experiments. Experimental results show that measurement precision is larger than theoretical values. Furthermore, method for improving the measurement ...

• 대한전자공학회논문지
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• 제9권1호
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• pp.1-6
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• 1972

통계적 상관법에 의하여 최대주기계열 신호를 시험신호로 2차 진동계의 임펄스 응답 추정에 관하여 이론적 및 실험적으로 검토 하였고, 그 측정 결과는 비교적 만족스러웠다. 이 방법은 실제 푸로쎄스에 적용시키는 경우 시험신호를 가하는 방법 및 지연신호의 검출 방법의 해결과 더부러 계통의 동정(동정)문제에 크게 기여될 것으로 전망한다.

• 한국자기공명학회논문지
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• 제2권1호
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• pp.59-65
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• 1998

The correction of image artifacts due to misadjustment in tuning of RF coils (tip angle) and in the RF single sideband spectrometer was investigated using phase cycling of the $\pi$/2 and $\pi$ pulses in spin-echo sequences. A general procedure was developed for the systematic design of phase cycles that select desirable coherence transfer pathways. To analyze a phase cycling sequence, changes in the coherence level and phase factor for each RF pulse in the spin-echo cycle must be determined. Four different phase cycling schemes (FIXED, ALTERNATE, FORWARD, REVERSED) to suppress unwanted signal components such as mirror and ghost images were evaluated using two signal acquisitions. When the receiver phase factor is cycled counter-clockwise (REVERSED), these artifacts are completely removed.

• 한국통신학회논문지
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• 제27권10C호
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• pp.999-1007
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• 2002

본 논문에서는 DSSS (Direct Sequence Spread Spectrum) 수신기에서 초기동기 탐색에 사용될 수 있는 정합필터에 대해서 연구하였다. 하드웨어기술언어 (HDL)로 정합필터를 구현하기 위한 모델이 제시되었다. 제안된 모델은 고속 처리를 위해 병렬처리와 파이프라인 구조를 기반으로 하는데 환형버퍼, 곱셈기, 덧셈기, 코드참조표 등으로 구성되어 있다. 제안된 모델에 대해 성능을 분석하였고 일반적인 DSP (Digital Signal Processor)로 구현할 경우와 비교하였다. 제안된 모델을 FPGA (Field Programmable Gate Array)상에 구현하였고 타이밍 시뮬레이션 결과를 통해서 동작을 검증하였다.

• 한국자기공명학회논문지
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• 제25권1호
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• pp.1-7
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• 2021

Employing of 13C stable-isotopes in NMR metabolomics can give unique splitting patterns and coupling constants information originated from 13C-13C coupling interaction that provide an important structural information regarding the cellular metabolic process. But it has been known that an undesirable signal distortion in 2D heteronuclear correlation study, due to 13C-13C interaction, hampers an analysis of the coupling information. Recently, we proposed J-scaled distortion-free heteronuclear single-quantum coherence (HSQC) sequence which provides a distortion-free 13C-13C coupling information with a selective resolution enhancement of JCC splitting. In this paper, we dicuss theoretical aspect and practical feature of J-scaled HSQC pulse sequence. The conceptual explanation of orgin of the signal distortion by 13C-13C coupling interaction and design of J-scaled HSQC through exemplified results are provided in brief.

• 한국해양바이오학회지
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• 제16권1호
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• pp.55-62
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• 2024

Various antimicrobial peptides (AMPs) from microalgae have shown antibacterial, antiviral, antifungal, anticancer, and antioxidant effects, and play crucial roles in medical applications, aquaculture-related disease management, and the food industry. Magainin 2 (MAG2), an AMP, exhibits high antibacterial and antitumor activity, necessitating an efficient recombinant expression system for low-cost, large-scale production. To enhance MAG2 secretion efficiency in Chlorella, we constructed the SS:MAG2:His vector using the known Chlamydomonas reinhardtii CA1 signal sequence (SS) and obtained a stable transformant via an Agrobacterium-mediated transformation method and RT-qPCR. ELISA results revealed that the MAG2 content secreted into the medium by the SS:MAG2:His transformants increased proportionally with mRNA expression. These findings offer a strategy for high MAG2 secretion in the Chlorella vulgaris platform, potentially minimizing downstream processing costs.

• Journal of Life Science
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• 제11권2호
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• pp.94-98
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• 2001

Type I signal peptidase cleaves the signal sequence from the amino terminus of membrane and secreted proteins afters these protein insert across the membrane. This enzyme serves as a potential target for the development of novel antibacterial agents due to its unique physiological and biochemical properties. Despite considerable research, the signal peptidase assay still remains improvement to provide further understanding of the mechanism and high-throughput inhibitor screening of this enzyme. In this paper, three known signal peptidase assays are tested with an E. coli D276A mutant signal peptidase to distinguish the sensitivity of each assays. In vitro assay using the procoat synthesized by in vitro transcription translation shows that the D276A signal peptidase I was inactive while in vivo processing of pro-OmpA expressed in the temperature-sensitive E. coli strain IT41 as well as in vitro assay using pro-OmpA nuclease A substrate show that D276A signal peptidase I has activity like wild-type signal peptidase. These results suggest that in vitro assay using the pro-OmpA nuclease A and in vivo pro-OmpA processing assay are more sensitive monitors than in vitro assay using the pro-coat. In conculsion, caution should be used when interpreting the in vitro results using the procoat.

• 한국양식학회지
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• 제14권1호
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• pp.9-16
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• 2001

Characterization of a single pass of cDNA sequence, an expressed sequence tag (EST) has been a fast growing activity in fish genomics. Despite its relatively short history, fish EST databases (dbESTs) have already begun to play a significant role in bridging the gaps in our knowledge on the gene expression in fish genome. This review provides a brief description of the technology for establishing fish dbESTs, its current status, and implication of the ESTs to aquaculture and fisheries science with particular emphasis on the discovery of novel genes for transgenic application, the use of polymorphic EST markers in genetic linkage mapping and the evaluation of signal-responsive gene expression.