• Journal of Microbiology and Biotechnology
• /
• 제17권12호
• /
• pp.2046-2055
• /
• 2007

Wild-type V. vulnificus cannot grow using lactose as the sole carbon source or take up the sugar. However, prolonged culture of this species in media containing lactose as the sole carbon source leads to the generation of a spontaneous lactose-utilizing (LU) mutant. This mutant showed strong ${\beta}$-galactosidase activity, whereas the wild-type strain showed a barely detectable level of the activity. A mutant with a lesion in a gene homologous to the lacZ of E. coli in the bacterium no longer showed ${\beta}$-galactosidase activity or generated spontaneous LU mutants, suggesting that the lacZ homolog is responsible for the catabolism of lactose, but the expression of the gene and genes for transport of lactose is tightly regulated. Genetic analysis of spontaneous LU mutants showed that all the mutations occur in a lacI homolog, which is located downstream to the lacZ and putative ABC-type lac permease genes. Consistent with this, a genomic library clone containing the lad gene, when present in trans, made the spontaneous LU mutants no longer able to utilize lactose as the sole carbon source. Taken together with the observation that excessive amounts of exogenously supplemented possible catabolic products of lactose have negative effects on the growth and survivability of V. vulnificus, we suggest that V. vulnificus has evolved to carry a repressor that tightly regulates the expression of lacZ to keep the intracellular toxic catabolic intermediates at a sublethal level.

• Journal of Microbiology and Biotechnology
• /
• 제17권1호
• /
• pp.138-145
• /
• 2007

Anabaena sensory rhodopsin is a seven transmembrane protein that uses all-trans/13-cis retinal as a chromophore. About 22 residues in the retinal-binding pocket of microbial rhodopsins are conserved and important to control the quality of absorbing light and the function of ion transport or sensory transduction. The absorption maximum is 550 nm in the presence of all-trans retinal at dark. Here, we mutated Pro206 to Glu or Asp, of which the residue is conserved as Asp among all other microbial rhodopsins, and the absorption maximum and pKa of the proton acceptor group were measured by absorption spectroscopy at various pHs. Anabaena rhodopsin was expressed best in Escherichia coli in the absence of extra leader sequence when exogenous all-trans retinal was added. The wild-type Anabaena rhodopsin showed small absorption maximum changes between pH4 and 11. In addition, Pro206Asp showed 46 nm blue-shift at pH7.0. Pro206Glu or Asp may change the contribution to the electron distribution of the retinal that is involved in the major role of color tuning for this pigment. The critical residue Ser86 (Asp 96 position in bacteriorhodopsin: proton donor) for the pumping activity was replaced with Asp, but it did not change the proton pumping activity of Anabaena rhodopsin.

• Journal of Microbiology and Biotechnology
• /
• 제18권2호
• /
• pp.219-227
• /
• 2008

The free-living photoheterotrophic Gram-negative bacterium Rhodobacter sphaeroides possesses a quorum-sensing (QS) regulatory system mediated by CerR-CerI, a member of the LuxR-LuxI family. To identify the genes affected by the regulatory system, random lacZ fusions were generated in the genome of R. sphaeroides strain 2.4.1 using a promoter-trapping vector, pSG2. About 20,000 clones were screened and 23 showed a significantly different level of ${\beta}$-gal activities upon the addition of synthetic 7,8-cis-N-tetradecenoyl-homoserine lactone (RAI). Among these 23 clones, the clone showing the highest level of induction was selected for further study, where about a ten-fold increase of ${\beta}$-gal activity was exhibited in the presence of RAI and induction was shown to be required for cerR. In this clone, the lacZ reporter was inserted in a putative gene that exhibited a low homology with catD. A genetic analysis showed that the expression of the catD homolog was initiated from a promoter of another gene present upstream of the catD. This upstream gene showed a strong homology with luxR and hence was named qsrR (quorum-sensing regulation regulator). A comparison of the total protein expression profiles for the wild-type cells and qsrR-null mutant cells using two-dimensional gel electrophoresis and a MALDI-TOF analysis allowed the identification of sets of genes modulated by the luxR homolog.

• 청정기술
• /
• 제13권4호
• /
• pp.257-265
• /
• 2007

반도체 공정에서 배출되는 폐 포토레지스트 스트리퍼(photoresist stripper)의 주성분인 NMP (N-methy-pyrrolodione)와 BDG (Butyldiglyrcol)를 회수하여 재활용할 목적으로 나선형 스핀밴드시스템(spinning band stem)이 장착되어 있는 진공증류장치를 이용하여 실험실적 규모의 증류실험을 수행하였다. 정제된 NMP와 BDG의 순도는 포토레지스트 스트리퍼용 용제 기준 물성치인 순도 99.5% 이상이었고, 수분 1000 ppm 이하, 색도(APHA) 50 이하, 나트륨 성분을 제외한 대부분의 금속성분은 1 ppb 이하로 반도체용 스트리퍼 용액 제조에 재활용할 수 있는 수준임을 확인하였다. NMP와 BDG의 회수을은 PR스트리퍼 폐액 A 타입의 경우 NMP 96%, BDG 53%, B 타입의 경우 NMP 93%, BDG 57%이었다.

• Macromolecular Research
• /
• 제11권1호
• /
• pp.25-35
• /
• 2003

A series of random poly(ethylene-co-1,4-butylene terephthalate)s (PEBTs), as well as poly(ethylene terephthalate) (PET) and poly(1,4-butylene terephthalate) (PBT), were synthesized by the bulk polycondensation. Their composition, molecular weight, and thermal properties were determined. All the copolymers are crystallizable, regardless of the compositions, which may originate from both even-atomic-numbered ethylene terephthalate and butylenes terephthalate units that undergo inherently crystallization. Non-isothermal crystallization exotherms were measured over the cooling rate of 2.5-20.0 K/min by calorimetry and then analyzed reasonably by the modified Avrami method rather than the Ozawa method. The results suggest that the primary crystallizations in the copolymers and the homopolymers follow a heterogeneous nucleation and spherulitic growth mechanism. However, when the cooling rate increases and the content of comonomer unit (ethylene glycol or 1,4-butylene glycol) increases, the crystallization behavior still becomes deviated slightly from the prediction of the modified Avrami analysis, which is due to the involvement of secondary crystallization and the formation of relatively low crystallinity. Overall, the crystallization rate is accelerated by increasing cooling rate but still depended on the composition. In addition, the activation energy in the non-isothermal crystallization was estimated.

• 디지털융복합연구
• /
• 제20권5호
• /
• pp.833-846
• /
• 2022

본 연구는 여대생을 대상으로 거주 형태에 따른 영양 지식, 식이 행동 및 식이 행동 개선 통합프로그램에 대한 요구도를 파악하기 위해 실시되었다. 자료는 2021년 3월 16일에서 4월 16일까지 온라인을 통해 자가보고식 설문지를 이용해 수집되었고, 최종 217명의 자료가 이용되었다. 수집된 자료는 SPSS WIN 26.0을 사용해 빈도와 백분율, 평균과 표준편차, 독립표본 t-test와 ANOVA로 분석하였다. 그 결과, 자택 거주자가 자취하는 대상자보다 식이 행동을 더 잘하는 것으로 나타났고, 식이 행동 개선 통합프로그램에 대한 요구는 자택 거주자와 자취하는 대상자가 기숙사에 거주하는 대상자보다 '질병 및 건강 정보'에 대한 요구도가 더 높은 것으로 파악되었다. 그러므로 여대생에 대한 식이행동 개선 통합프로그램 개발 시 거주 형태를 고려한 차별화 된 중재프로그램의 적용이 필수적일 것이다.

• 산업융합연구
• /
• 제20권7호
• /
• pp.57-64
• /
• 2022

지하공간에는 다양한 구조물들이 있고 그 구조물들의 지하공간 데이터는 지하공간통합지도 관리 시스템(IUGMMS)에서 3D 데이터로 관리되고 있다. 작업자는 준공도서 제출 프로그램으로 변경된 지하공간 데이터를 반영한 통합지도 전체를 IUGMMS에 전송하여 갱신하고 있다. 그러나 통합지도 파일의 크기가 크기 때문에 전송하고 갱신하는 시간이 지연되는 문제점이 있다. 본 논문에서는 변경된 통합지도와 IUGMMS에 저장되어 있는 통합지도에서 공간특성정보를 각각 구하고 비교해서 변경된 지하정보 데이터가 있는 통합지도만 추출하여 전송하고자 한다. 실험 결과, 기존 방법은 전송하려는 통합지도의 영역이 넓을수록 통합지도를 전송하는 시간과 갱신하는 시간이 파일 크기에 비례하여 증가하였지만, 제안한 방법은 변경된 지하공간 데이터가 포함된 통합지도만 전송하기 때문에 전송 시간이 짧았고 갱신하는 시간도 짧았다. 그 결과 변경된 통합지도를 전송하고 갱신할 때 발생하는 시간의 지연을 줄일 수 있었다.

• 한국보육지원학회지
• /
• 제8권2호
• /
• pp.27-61
• /
• 2012

본 연구의 목적은 유아들의 음악표현능력, 언어표현능력 및 창의성을 증진시킬 수 있는 노래동화를 활용한 통합적 유아음악교육 프로그램을 개발하고, 그 프로그램에 따라 교육을 실시하여 유아의 음악표현능력, 언어표현능력 및 창의성 증진의 효과를 검증하는데 있다. 노래동화를 활용한 통합적 유아음악교육 프로그램을 구성하기 위해 연구대상 어린이 집에서 사용될 노래를 검토하여 곡을 선정하고, 선정된 곡을 토대로 노래동화를 개작하고, 노래부르기, 악기다루기, 음악만들기 등의 음악 영역간의 통합과 신체표현, 언어표현, 그림(선)표현 등의 타 영역간의 통합적 활동내용을 포함하여 통합적 유아음악교육 프로그램을 개발하였다. 본 연구의 대상은 두 곳 어린이집의 만 4세 유아 68명을 각각 실험집단과 통제집단으로 배정하여 실험집단에게 프로그램을 8주간 총 16회에 걸쳐서 적용하였다. 자료분석은 음악표현능력, 언어표현능력, 창의성의 집단간 차이검증을 위해 t 검증을 실시하였다. 그 결과 : 첫째, 노래동화를 활용한 통합적 유아음악교육 프로그램에 참여는 유아의 음악표현능력 및 언어표현능력 증진에 효과가 나타났다. 둘째, 노래동화를 활용한 통합적 유아음악교육 프로그램에 참여는 유아의 유창성 증진에 효과가 나타났다.

• 가정과삶의질연구
• /
• 제26권6호
• /
• pp.209-225
• /
• 2008

This study has been designed to develop integrated supportive service works for the families of disabled children registered in the D-Healthy Family Support Center. The service works are intended to improve family members' health and their growth potentials, and cover service programs of family education, counselling, culture solidarity, and information networks. There are two topics covered in this study; first, this study is to develop integrated supportive service programs for the families of disabled children, and second, the study is also to construct comprehensive strategies and plans for effective services after evaluating practical service programs. In this study, 31 families with one or more disabled children have been selected through stratified random sampling, and all the family members were observed for program effects of integrated service items developed from previously validated indices. For analysis, eight question items were made for interview and each item denotes satisfaction score ranging from 1(very dissatisfied) to 5(very satisfied) on the Likert's five point scale. Mean value of each item was counted after the program, and satisfaction scores were compared over the programs implementation. Overall, the satisfaction scores range 4.1 to 4.6, indicating relatively high satisfaction over most service program. Therefore, it is finally proposed that a longitudinal strategy model offer high quality service programs consistently for the target families, as a goal of achieving comprehensive cooperation and support exchanges between community and healthy family support center be schematized.

• Journal of Positioning, Navigation, and Timing
• /
• 제13권1호
• /
• pp.45-52
• /
• 2024

As part of the Global Positioning System (GPS) modernization program in the United States, Civil Navigation (CNAV) and CNAV-2 messages were developed to introduce flexibility and modern features to the Legacy Navigation (LNAV) message. This paper explores the additional parameters introduced in CNAV/CNAV-2 compared to LNAV, focusing on their roles from the user's perspective. This paper compares the structural and parameter differences among LNAV, CNAV, and CNAV-2. Additionally, we analyze the types and roles of parameters newly incorporated into CNAV/CNAV-2 that were absent in LNAV.