• Journal of the Korean Chemical Society
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• v.34 no.3
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• pp.232-238
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• 1990

To study the biological roles of Zn, we investigated simple model systems of $Zn^{++}, coordinated with OH_2 or NH_3,$ or with O=C- in peptide. The geometrical structures and net atomic charges were calculated by the ab initio HF-SCF theory using double zeta basis sets. The ligands of O-H, N-H, and O=C- are very polar due to $Zn^{++}$. Therefore, the carbon atom in peptide becomes so electrophilic that it can be easily attacked by other nucleophiles. In addition, to understand how $Zn^{++}$ is coordinated with ligands in enzyme, a molecular mechanics method is applied to the system of the enzyme of carboxypeptidase A (CPA) with the substrate of glycyltyrosine. From our results, it appears that the Zn ion is coordinated not only by four ligands in enzyme and substrate but also by one water molecule.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.363-366
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• 1998

Supercritical fluid(SCF) carbon dioxide was used to extract safflower yellow pigments from Carthamus tinctorius L. In this work, supercritical fluid extractions were performed at various conditions; pressure (2000, 3000, 4000, 5000 psig), temperature $(40,\;50,\;60,\;70,\;80^{\circ}C)$ and co-solvent $(0,\;3,\;6,\;10,\;14\;wt%\;H_2O)$. Total concentrations of safflower yellow pigments extracted were determined by spectrophotometric method. A maximum yield of yellow pigments was obtained at 4000psig, $60^{\circ}C$ and 10% co-solvent. The extraction yield of pigments was also closely related to moisture content of the raw material. Extraction yield of safflower yellow pigments by SCF extraction at optimized conditions was 6% higher than that by solvent extraction. Supercritical carbon dioxide was proved to be suitable for the extraction of safflower yellow pigments from Carthamus tinctorius L.

• Journal of the Korean Solar Energy Society
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• v.38 no.4
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• pp.55-66
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• 2018

nZEH (net-Zero Energy House) is defined as a self-sufficient energy building where the sum of energy output generated from new & renewable energy system and annual energy consumption is zero. The electricity generated by new & renewable energy system with the form of distributed generation is preferentially supplied to electrical demand, and surplus electricity is transmitted back to grid. Due to the recent expansion of houses with photovoltaic system and the nZEH mandatory by 2025, the rapid increase of distributed generation is expected. Which means, we must prepare for an electricity-power accident and stable electricity supply. Also electricity charges have to be reduce and the grid-connected should be operated efficiently. The introduction of ESS is suggested as a solution, so the analysis of the load matching and grid interaction is required to optimize ESS design. This study analyzed the load matching and grid interaction by expected consumption behavior using actual data measured in one-minute intervals. The experiment was conducted in three nZEH with photovoltaic system, called all-electric houses. LCF (Load Cover Factor), SCF (Supply Cover Factor) and $f_{grid}$ (Grid Interaction Index) were evaluated as an analysis indicator. As a result, LCF, SCF and $f_{grid}$ of A house were 0.25, 0.23 and 0.27 respectively; That of B house were 0.23, 0.23, 0.19, and that of C were 0.20, 0.19, 0.27 respectively.

• Animal cells and systems
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• v.16 no.4
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• pp.280-288
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• 2012

Targeted degradation of proteins through ubiquitin-mediated proteolysis is an important control mechanism in various cellular processes. The process of ubiquitin conjugation is achieved by three enzyme complexes, among which the ubiquitin ligase complex (E3) is in charge of substrate specificity. The SCF (SKP1-CUL1-F-box) family portrays the largest and the most characterized member of the E3 ligases. For each SCF complex, the ubiquitination target is recognized by the F-box protein subunit, which interacts with the substrate through a unique C-terminal domain. We have characterized a novel F-box protein CFL-1 that represents a single LRR-type F-box (FBXL) in the Caenorhabditis elegans genome. CFL-1 is highly homologous to FBXL20 and FBXL2 of mammals, which are known to regulate synaptic vesicle release and cell cycle, respectively. A green fluorescence protein (GFP)-reporter gene fused to the cfl-1 promoter showed restricted expression around the amphid and the anus. Modulation of CFL-1 activity by RNAi affected the time interval between defecations. RNAi-treated worms also exhibited reduced tendency to form dauer when exposed to daumone. The potential involvement of CFL-1 in the control of defecation and pheromone response adds to the ever expanding list of cellular processes controlled by ubiquitin-mediated proteolysis in C. elegans. We suggest that CFL-1, as a single LRR-type F-box protein in C. elegans, may portray a prototype gene exerting diverse functions that are allocated among multiple FBXLs in higher organisms.

• Molecules and Cells
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• v.38 no.10
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• pp.829-835
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• 2015

It has been suggested that AUXIN BINDING PROTEIN 1 (ABP1) functions as an apoplastic auxin receptor, and is known to be involved in the post-transcriptional process, and largely independent of the already well-known SKP-cullin-F-box-transport inhibitor response (TIR1) /auxin signaling F-box (AFB) ($SCF^{TIR1/AFB}$) pathway. In the past 10 years, several key components downstream of ABP1 have been reported. After perceiving the auxin signal, ABP1 interacts, directly or indirectly, with plasma membrane (PM)-localized transmembrane proteins, transmembrane kinase (TMK) or SPIKE1 (SPK1), or other unidentified proteins, which transfer the signal into the cell to the Rho of plants (ROP). ROPs interact with their effectors, such as the ROP interactive CRIB motif-containing protein (RIC), to regulate the endocytosis/exocytosis of the auxin efflux carrier PIN-FORMED (PIN) proteins to mediate polar auxin transport across the PM. Additionally, ABP1 is a negative regulator of the traditional $SCF^{TIR1/AFB}$ auxin signaling pathway. However, Gao et al. (2015) very recently reported that ABP1 is not a key component in auxin signaling, and the famous abp1-1 and abp1-5 mutant Arabidopsis lines are being called into question because of possible additional mutantion sites, making it necessary to reevaluate ABP1. In this review, we will provide a brief overview of the history of ABP1 research.

• 한국노년학
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• v.36 no.3
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• pp.809-826
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• 2016

This study analyzed private pension dependency of Korea and U.S. households using the most recent dataset of two countries. For this purpose, 2013 Korean Retirement and Income Study(KReIS) of national pension research institute in Korea and 2013 SCF(Survey of Consumer Finances) of FRB in U.S. were used. The private pension dependency was defined as the proportion of private pension wealth among total financial wealth in each household and tobit model was used to investigate determinants of private pension dependency of the two countries. After controlling for other factors, household income and net worth, age, educational attainment, and health status of householder were crucial determinants of private pension dependency for both countries. Householder's age, educational attainment, and health tend to increase the private pension dependency in Korea and U.S. However, household income and net worth affected the private pension dependency opposite direction. The private pension dependency increased with high level of income and net worth in Korea, while it decreased with high level of income and net worth in U.S. Results of this study provide useful implications for future pension system and policy in Korea.

• Journal of Korea Trade
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• v.26 no.3
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• pp.23-44
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• 2022

Purpose - Recent issues such as vessel enlargement, strengthening of environmental regulations, and port smartization are expected to increase costs and intensify competition in the port industry. In the new normal era, when external growth has reached its limit, the efficient operation of ports is becoming indispensable for achieving sustainable growth. This study aims to identify the determinants of inefficiency by examining the cost structure and efficiency of container terminals in Korea and furthermore propose the political implications to derive the maximization of efficiency. Design/methodology - This study estimates the cost function of container terminal operators and identifies the efficiency of container terminals using stochastic cost frontier (SCF) in the first stage. In the second step, the SCF results are compared with the data envelopment analysis (DEA). Last, this paper proposes efficiency determinants on container terminal operation to establish appropriate strategies. Out of the 29 container terminal operators in South Korea, 13 operators participated in the survey. The translog cost function was estimated utilizing a total of 116 observations collected over the 2007-2017 period. Findings - Empirical analysis shows that economies of scale exist in Korea's container ports, which provides a rationale for the government's policy to establish the global terminal operator by integrating small terminal operators to enhance competitiveness. In addition, as a result of the determinants analysis, container throughput, weight of direct employment costs, and labour cost share have positive effects on improving cost efficiency, while inefficiency increases as the length of quay increases. More specifically, cost efficiency improves as the proportion of direct employment costs to outsourcing service costs increases. Originality/value - This study contributes to analyzing the inefficiency factors of container terminals through efficiency analysis with respect to a cost function. In addition, this study proposes the practical and political implications, such as establishing a long-term manpower pool, the application of the hybrid liner terminal system, and the construction of a statistical data system, to improve the cost inefficiency of terminal operators.

• Progress in Medical Physics
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• v.34 no.1
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• pp.10-13
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• 2023

Patients with breast cancer can be positioned with their head turned to the contra lateral side or with their head straight during the radiation therapy treatment set-up. In our hospital, patients with locally advanced breast cancer who were receiving radiation therapy have experienced swallowing difficulty after 2 weeks of irradiation. In this pilot study, the impact of head position on reducing dysphagia occurrence was dosimetrically evaluated. Patients were divided into two groups viz., HT (head turned to the contra lateral side of the breast) and HS (head straight) with 10 members in each. Treatment planning was performed, and the dosimetric parameters such as Dmin, Dmax, Dmean, V₅, V₁₀, V₂₀, V₃₀, V₄₀, and V₅₀ of both groups were extracted from the dose volume histogram (DVH) of esophagus. The target coverage in the supraclavicular fossa (SCF) region was analyzed using D₉₅ and D₉₈; moreover, the dose heterogeneity was assessed with D₂ from the DVHs. The average values of the dose volume parameters were 27.6%, 58.6%, 35.4%, 19%, 13.8%, 14.1%, 11.8%, 8.4%, and 8.1% higher in the HT group compared with those in the HS group. Furthermore, for the SCF, the mean values of D₉₈, D₉₅, and D₂ were 42.4, 47.5, and 54 Gy, respectively, in the HS group and 38.9, 45.35, and 55.5 Gy, respectively, in the HT group. This pilot study attempts to give a solution for the poor quality of life of patients after breast radiotherapy due to dysphagia. The findings confirm that the head position could play a significant role in alleviating esophageal toxicity without compromising tumor control.

• The Journal of Pediatrics of Korean Medicine
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• v.14 no.1
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• pp.79-116
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• 2000

The KGBT has been used to weak children with anorexia, fatigue, and growth retardation. This study was carried out to prove the effects of the hematopoiesis and the immune proliferation by KGBT. Previously, C57BL/6 mice was treated with cyclophosphamide(100mg/kg) for leukopenia, and then administered KGBT (concentration is 1.37 g/kg, 504 mg/kg, and 137 mg/kg) to the treated mice. The mice was analyzed expression of thrombopoietin(TPO), stem cell factor(SCF) and interleukin-3 from bone marrow cell, interleukin-10 (IL-10), and interferon-$ {\gamma}$(INF-${\gamma}$) from splenic cell, and NOSⅡ gene from macrophage using by RT-PCR. Also proliferation of immune cell was analyzed using 3H-thymidine uptake and flow cytometery in splenic cells. The results were obtained as follows ; 1. The total number of WBC, RBC and PLT was increased in the KGBT treated group than in the control group. 2. In vitro, the proliferation of splenic cells was increased in normal, control, and KGBT treated group. And Administration of KGBT was reduced the cytotoxicity by CTX. 3. In bone marrow cell, the gene expression of immune regulatory factor that associated with hematopoiesis, such as TPO, SCF, and IL-13 was increased in the KGBT treated group than control. 4 The titer of hemagglutinin and hemolysin was increased in the KGBT treated group than control. 5. In analysis of positive leucocytes from splenic cell of BALB/c mice, the subpopulation percent of CD4+, CD8+,and CD19+ was increased in the KGBT treated group than control. The KGBT has been used to weak children with anorexia, fatigue, and growth retardation. This study was carried out to prove the effects of the hematopoiesis and the immune proliferation by KGBT. Previously, C57BL/6 mice was treated with cyclophosphamide(100mg/kg) for leukopenia, and then administered KGBT (concentration is 1.37 g/kg, 504 mg/kg, and 137 mg/kg) to the treated mice. The mice was analyzed expression of thrombopoietin(TPO), stem cell factor(SCF) and interleukin-3 from bone marrow cell, interleukin-10 (IL-10), and interferon-$ {\gamma}$(INF-${\gamma}$) from splenic cell, and NOSⅡ gene from macrophage using by RT-PCR. Also proliferation of immune cell was analyzed using 3H-thymidine uptake and flow cytometery in splenic cells. The results were obtained as follows ; 1. The total number of WBC, RBC and PLT was increased in the KGBT treated group than in the control group. 2. In vitro, the proliferation of splenic cells was increased in normal, control, and KGBT treated group. And Administration of KGBT was reduced the cytotoxicity by CTX. 3. In bone marrow cell, the gene expression of immune regulatory factor that associated with hematopoiesis, such as TPO, SCF, and IL-13 was increased in the KGBT treated group than control. 4 The titer of hemagglutinin and hemolysin was increased in the KGBT treated group than control. 5. In analysis of positive leucocytes from splenic cell of BALB/c mice, the subpopulation percent of CD4+, CD8+,and CD19+ was increased in the KGBT treated group than control. 6. The expression of IL-10 gene was reduced in the KGBT treated group than control, whereas the expression of INF-${\gamma}$ was increased in the KGBT treated group. 7. In macrophage, the production of NO and gene expression of NOSH was increased in the KGBT treated group than control. 8. After infection of EMC virus, the survival time of infected mice was longer in the KGBT treated group than control.

• International Journal of Human Ecology
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• v.4 no.2
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• pp.55-75
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• 2003

The purpose of this study was to investigate the effect of employment related factors on household savings for precautionary purposes when controlling for financial security and to compare the results between the two different economic periods. A conceptual framework was developed based on the precautionary saving theory, the family stress theory, and previous empirical studies. As a self-insurance, a measure of security funds were developed and used as the dependent variable. Using data on working households in the 1992 and the 1998 Survey of Consumer Finances (SCF), a MLE estimation was conducted on the pooled data. The 1992 and 1998 data were used to reflect periods of economic recession and expansion, respectively. The results suggested that factors representing resources played the most significant role in determining the amount of security funds. Some of the employment related factors, preferences, financial security, and race were also significantly affected the amount of security funds. The results suggested that stable employment conditions were important for households to accumulate security funds. Households with more human resources and financial resources had a larger amount of security funds than those that had less human and financial resources. From the findings, implications for research, policies, and financial educators had been suggested.