• 상하수도학회지
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• 제32권5호
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• pp.371-379
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• 2018

The lack of seed sludges for Ammonium Oxidizing Bacteria (AOB) and slow-growing ANaerobic AMMonium OXidation (ANAMMOX) bacteria is one of the major problem for large-scale application. In this study, $24m^3$ of single-stage SBR (Sequencing Batch Reactor) was operated to remove nitrogen from reject water using AOB and ANAMMOX bacteria cultivated from activated sludge in the field. The ANAMMOX activity was found after 44 days of cultivation in the ANAMMOX cultivation reactor, and then $0.66kg\;N/m^3/d$ of the nitrogen removal rate was achieved at $0.78kg\;N/m^3/d$ of the nitrogen loading rate at 153 days of cultivation. The AOB cultivation reactor showed $0.2kg\;N/m^3/d$ of nitrite production rate at $0.4kg\;N/m^3/d$ of nitrogen loading rate after 36 days of operation. The cultivated ANAMMOX bacteria and AOB was mixed into the single-stage SBR. The feed distribution was applied to remove total nitrogen stably in the single-stage SBR. The nitrogen removal rate in the single-stage SBR was gradually enhanced with an increase of specific activities of both AOB and ANAMMOX bacteria by showing $0.49kg\;N/m^3/d$ of the nitrogen removal rate at $0.56kg\;N/m^3/d$ of the nitrogen loading rate at 54 days of operation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권2호
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• pp.85-99
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• 2004

Purpose: This study observed the changes in the telomerase activity, it's developmental regulation, PCNA expression, and their correlation in rat's upper digestive organs during growth and aging. Materials and Methods: Upper digestive organs(buccal mucosa, gingiva, palate, submandibular and parotid glands, and tongue) were aseptically removed from Sprague-Dawley rats of fetal(gestational 20 days), growing(1, 2, 3, 5, and 7 weeks after birth) and adult(12 week old). Samples for telomerase activity were frozen on liquid nitrogen immediately after sacrifice, and stored until the use at $-75^{\circ}C$ in order to measure it. Telomerase activity was measured by a PCR-based telomeric repeat amplication protoco(TRAP) assay and quantitated with Photometric Telo TAGGG Telomerase PCR ELISA plus(Roche Diagnostics GmbH. Mannheim. Germany). PCNA expression were measured immunohistochemistry with anti PCNA Ab-1, Clone PC10(NeoMark. California. USA). Results: 1. Telomerase activities in buccal mucosa, palate and gingiva were the highest in fetus and decreased gradually or rapidly after birth and then diminished, but In salivary gland and tongue were the highest in fetus and also high at 1 week and then decreased rapidly. 2. PCNA expression in buccal mucosa, gingiva, Tongue and salivary gland was the highest in fetus and decreased gradually and then diminished. but only in palate decreased rapidly after birth and then diminished. Conclusion: The highest telomerase activity of embryonic stage decreased rapidly after birth in rat's upper digestive organs. There may be a developmental regulation of telomerase activity, but not a tissue-specific. This telomerase activity seems correlated closely with PCNA expression in rat's upper digestive system.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.334-344
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• 2021

The study has suggested a way to minimize safety accidents found in on-site firefighting activity by analyzing firefighters' [investigation report on accidents to on-sie workers]. The study result is described as follows. First, the result of [investigation report on on-site workers] shows that while accidents are found to most frequently have occurred to low-ranking firefighting officers such as Sobangsa and Sobanggyo and firefighting officers with career of less than 5 years, fire-extinguishing activity proved to be the most prone to accidents in the category of activity. Second, analysis performed to identify variance between injury extent and area based on cause of accident shows statistically significant variance. In addition, the result of verifying difference in cause of accident based on category of activity shows significant difference with 'falling over and sliding' being the highly likely cause of accident in fire containment and rescue activities and 'reckless move' being highly likely case of accident in emergency activities. Third, the result of verifying factors behind the extent of injury done to on-site workers shows that when accident is caused by 'incomplete behavior', it was found that the extent of injury is substantial. It was also found that rescue activity is accompanied by substantial extent of injury. As a solution to this, the study suggested ways to establish, extend and operate safety-specific curriculum for entrants, develop materials regarding risk prognosis training and explicate training-related regulations, set up safety management measure for a single squad team, upgrade performance of private protection equipment, institutionalize SOP by on-site activity stage, materialize and activate swift rescue team and increase objectivity and proficiency of safety accident investigation.

• 식물조직배양학회지
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• 제21권1호
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• pp.15-22
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• 1994

쎌러리(Apium graveolens L.)의 체세포배 발생 및 인공종자 발아에 있어서 분자수준의 기작을 이해하기 위하여 ABA 및 저온처리에 의한 단백질합성변화에 관한 연구를 수행하였다. 단백질함량과 질산환원효소 활성도는 ABA 및 저온처리한 체세포배 및 유식물은 처리하지 아니한 것에 비하여 특히 유식물에서보다 체세포배 발생시에 더욱 높았다. 2차원 전기영동결과 ABA 및 저온처리에 의하여 심장 형배 시기에서는 30 KD, 32 KD, 171 KD 및 205 KD의 단백질과 자엽시기배에서는 29 KD, 33 KD, 37 KD, 38 KD, 41 KD, 55 KD, 66 KD, 및 110 KD 단백질이 합성되어졌다. 또한 심장형배에서는 42 KD, 44 KD, 59 KD, 64 KD, 101 KD, 104 KD, 및 190 KD의 단백질과 자엽시기에서는 29 KD 및 116 KD의 단백질이 억제되었다. 체세포배 발생 및 인공종자 발아에 있어서 ABA및 저온처리에 의해서 단백질이 합성되어지거나 억제되는 것이 동시에 일어났으며 주로 산성단백질에서 변화가 일어났다. 이와같은 결과는 체세포배 발생과정에서 그리고 체세포배 발아와 유식물의 생장과정에서 환경변화에 적응하기 위한 대사상의 변화가 일어나는 것으로 추정된다.

• 대한수학교육학회지:학교수학
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• 제13권1호
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• pp.189-206
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• 2011

본 연구는 초등학생에게 알맞은 수학과 PBL(문제중심학습)의 목표와 모형을 개발하여 실제 수업에 적용 분석함으로써 수학 교과에서의 PBL에 대한 실천적 이해와 구체적인 방안을 제시하는 것을 목적으로 한다. 본 연구는 7차 개정 수학과 교육과정의 목표를 구현할 수 있도록 지식, 기능, 태도 영역으로 구분하여 10가지 목표를 설정하고 수학과 PBL 목표 기준을 표로 제시하였다. 또한 기존의 PBL 모형을 수정 보완하여 초등학교에 적합한 수학과 PBL 모형을 개발하고자 수학적 의미화, 수리 정보 수집 단계를 추가하고 정리단계를 강화한 초등학교 수학과 PBL 모형을 제시하였다. 이를 초등학교 4학년 소수 단원에 두 차례의 현장 적용을 하는 동안 4명의 개별 학생들의 수학과 PBL 목표 도달여부와 반응을 살펴보았다.

• 정보관리학회지
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• 제29권3호
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• pp.99-122
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• 2012

본 연구는 과학기술분야 R&D 라이프사이클 각 단계 세부연구 목표를 달성하는 과정에서 이루어지는 정보행동(정보요구, 정보검색, 정보도구, 정보채널, 정보장애)을 과학기술커뮤니티 환경의 맥락에서 분석하였다. 이 연구는 의미형성이론, 일상생활정보탐색이론, 활동이론에 근거하여 과학기술자를 대상으로 질적 인터뷰연구를 통해 이루어졌으며, 연구결과 과학기술분야 R&D 라이프사이클 5단계는 14개의 세부 정보행동 단계로 이루어짐을 밝혀내었다. 과학기술 R&D 연구 세부단계별로 문제상황 극복을 위한 정보행동 규명은 연구자와 연구환경의 변화를 이해할 뿐만 아니라 향후 도서관 및 정보서비스 기관에서 과학기술 전주기적 정보서비스 전략을 수립하는데 기초자료로 활용될 것이다.

• 생명과학회지
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• 제22권9호
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• pp.1201-1206
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• 2012

Crlz1 유전자는 B 세포 분화 과정 중 pre-B 세포 분화 단계에서 특이적으로 발현됨이 밝혀져 있다. Crlz1 유전자의 발현과 연관되는 3개의 DNase I hypersensitive site (HSS8, 9, 10)가 Crlz1 유전자의 전사 시작점으로부터 바로 위쪽의 chromatin 상에서 발견되었고, 그 중에서 HSS9/10은 Crlz1 promoter 지역에 해당하며 매우 높은 전사 활성을 가지는 것으로 이미 보고 되었다. 본 연구에서는 앞의 연구에서 더 나아가 HSS8이 Crlz1 promoter의 전사활성을 약 2 배 증가시키는 enhancer의 역할을 하고 있는 현상을 밝혔으며, 또한 HSS8의 위치가 Crlz1 유전자의 전사 시작점을 기준으로 하였을 때 -1055와 -1159 사이, 즉 104 bp 길이의 chromatin DNA 상에 존재하며, 이러한 HSS8의 위치는 luciferase reporter의 활성 측정으로 비교 분석되어진 deletion construct들의 전사 활성에 대한 결과와도 잘 부합되었다.

• Nuclear Engineering and Technology
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• 제51권4호
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• pp.1098-1108
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• 2019

Korea's first commercial nuclear power plant at Kori site was permanently shut down in 2017 and is currently in transition stage. Preparatory activities for decommissioning such as historical site assessment, characterization, and dismantling design are being actively carried out for successful D&D (Dismantling and Decontamination) at Kori site. The ultimate goal of decommissioning will be to ensure the safety of workers and residents that may arise during the decommissioning of nuclear facilities and, thereby finally returning the site to its original status in accordance with the release criteria. Upon completion of decommissioning, the resident's safety at a site released will be assessed from the evaluation of dose caused by radionuclides expected to be present or detected at the site. Although the U.S. commercial nuclear power plants with decommissioning experience use different site release criteria, most of them are 0.25 mSv/y. In Korea, both the unrestricted and restricted release criteria have been set to 0.1 mSv/y by the Nuclear Safety and Security Commission. However, since the dose is difficult to measure, measurable concentration guideline levels for residual radionuclides that result in dose equivalent to the site release criteria should be derived. For this derivation, site reuse scenario, selection of potential radionuclides, and systematic methodology should be developed in planning stage of Kori site decommissioning. In this paper, for calculation of a preliminary site-specific Derived Concentration Guideline Levels (DCGLs) for the Nuclear Power Plant site, a novel approach has been developed which can fully reflect practical reuse plans of the Kori site by taking into account multiple site reuse scenarios sequentially, thereby striking a remarkable distinction with conventional approaches which considers only a single site scenario.

• BMB Reports
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• 제54권9호
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• pp.464-469
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• 2021

Cardiomyocyte differentiation occurs through complex and finely regulated processes including cardiac lineage commitment and maturation from pluripotent stem cells (PSCs). To gain some insight into the genome-wide characteristics of cardiac lineage commitment, we performed transcriptome analysis on both mouse embryonic stem cells (mESCs) and human induced PSCs (hiPSCs) at specific stages of cardiomyocyte differentiation. Specifically, the gene expression profiles and the protein-protein interaction networks of the mESC-derived platelet-derived growth factor receptor-alpha (PDGFRα)⁺ cardiac lineage-committed cells (CLCs) and hiPSC-derived kinase insert domain receptor (KDR)⁺ and PDGFRα⁺ cardiac progenitor cells (CPCs) at cardiac lineage commitment were compared with those of mesodermal cells and differentiated cardiomyocytes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that the genes significantly upregulated at cardiac lineage commitment were associated with responses to organic substances and external stimuli, extracellular and myocardial contractile components, receptor binding, gated channel activity, PI3K-AKT signaling, and cardiac hypertrophy and dilation pathways. Protein-protein interaction network analysis revealed that the expression levels of genes that regulate cardiac maturation, heart contraction, and calcium handling showed a consistent increase during cardiac differentiation; however, the expression levels of genes that regulate cell differentiation and multicellular organism development decreased at the cardiac maturation stage following lineage commitment. Additionally, we identified for the first time the protein-protein interaction network connecting cardiac development, the immune system, and metabolism during cardiac lineage commitment in both mESC-derived PDGFRα⁺ CLCs and hiPSC-derived KDR⁺PDGFRα⁺ CPCs. These findings shed light on the regulation of cardiac lineage commitment and the pathogenesis of cardiometabolic diseases.

• Animal Bioscience
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• 제35권4호
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• pp.533-543
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• 2022

Objective: Caspase-mediated apoptosis plays a crucial role in the regulation of endometrial and placental function in females. Caspase activity is tightly controlled by members of the inhibitors of apoptosis proteins (IAPs) family. However, the expression and regulation of IAPs at the maternal-conceptus interface has not been studied in pigs. Therefore, we determined the expression of IAP family members baculovirus IAP repeat-containing 1 (BIRC1) to BIRC6 at the maternal-conceptus interface in pigs. Methods: We obtained endometrial tissues from pigs at various stages of the estrous cycle and pregnancy, conceptus tissues during early pregnancy, and chorioallantoic tissues during mid- to late pregnancy and analyzed the expression of IAPs. Furthermore, we determined the effects of the steroid hormones estradiol-17β (E2) and progesterone on the expression of IAPs in endometrial explant tissue cultures. Results: During the estrous cycle, BIRC2 and BIRC5 expression varied cyclically, and during pregnancy, endometrial BIRC1, BIRC2, BIRC3, BIRC4, and BIRC5 expression varied in a stage-specific manner. Conceptus and chorioallantoic tissues also expressed IAPs during pregnancy. The BIRC2 and BIR3 mRNAs were localized to luminal epithelial cells, and BIRC4 proteins to glandular epithelial cells in the endometrium. Exposure of endometrial tissues to E2 increased the expression of BIRC6, while progesterone increased the expression of BIRC1, BIRC4, and BIRC6 in a dose-dependent manner. Conclusion: These results indicated that IAPs were expressed in the endometrium during the estrous cycle and at the maternal-conceptus interface during pregnancy in a stage-specific manner. In addition, steroid hormones were found to be responsible for the expression of some IAPs in pigs. Together, the results suggested that IAPs may play important roles in endometrial and placental functions by regulating caspase action and apoptosis at the maternal-conceptus interface.