• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Journal of Species Research
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• v.12 no.spc
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• pp.1-69
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• 2023

This study aims to establish a comprehensive, synthetic inventory system for the fauna and flora of Dokdo Island, Republic of Korea, which has been conducted by a specialized research group consisting of more than 50 experts. The research was conducted over five years(2015-2019) and supported by the National Institute of Biological Resources, Ministry of Environment, Republic of Korea. All possible publications on the fauna and flora of Dokdo Island over the last 68 years from 1952 to 2020 were reviewed. As a result, 1,302 species were found on Dokdo Island during the study period. An updated list of 1,963 species was created. This is expected to be of great help for the conservation and national publicity of important indigenous biological resources of Dokdo Island.

• Journal of Science and Technology Studies
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• v.5 no.1 s.9
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• pp.55-92
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• 2005

The factors contributing to the formation of an important scientific concept in South Korea and its circulation in the society are the scientific knowledge that had been already formed, matured, and established in the U.S.A, Europe and Japan and has been introduced into Korea, and the institutions that have been formed during the recent modernization in South Korea. The concept of 'genetic information' cannot be an exception in this context. The concept of genetic information is the one that has been extended and intensified by the genomics and bioinformatics formed and matured through the Human Genome Projects from the former concept of inheritance or heredity within the framework of classical and molecular genetics. The purpose of this study was to find out 'how the production structure of genetic information in South Korea has been formed', under the perspective of the conceptual, epistemic, and institutional holisticity or integratedness in the concept and knowledge production structure idealized in Western advanced nations. The discourse of genetic engineering popular in the mid 1980's in South Korea has catalyzed the development of molecular biology. However, the institutional balance that had been established for the biochemistry departments in Natural Science College and Medical College was not formed between the genetic engineering and genetics departments in South Korea. Therefore, they were unable to achieve the more integrative and macro-level disciplinary impact on life sciences, largely due to institutional lack of the capable (human) genetics departments in some leading Korean colleges of Medicine. In genomics, the cutting-edge reprogramming and restructuring of the traditional genetics in the West, South Korea has not invested, even meagerly, in the infrastructure, fund, and research and development (R & D) for the Basic or First Phase of the research trajectory in the Human Genome Project. Without a minimal Basic Phase, the genomics research and development in Korea has been running more or less for the Advanced or Second Phase. Bioinformatics has started developing in Korea under a narrow perspective which regards it as a mere sub-discipline of information technology (IT). Having developed itself in parallel with genomics, bioinformatics contains its own unique logics and contents that can be both directly and indirectly connected to the information science and technology. As a result, bioinformatics reveals a defect in respect of being synergistically integrated into genetics and life sciences in Korea. Owing to the structural problem in the production, genetic information appears to be produced in a fragmented pattern in the Korean society since its fundamental base is weak and thin. A good example of the conceptual and institutional fragmentedness is that 'the genetics of individual identification' is not a normal integrated part of the Korean genetics, but a scientific practice exercised in the departments of legal medicine in a few Medical Colleges. And the environment contributing to the production structure of genetic information in South Korea today comprises 'sangmyung gonghak'(or life engineering) discourse and non-governmental organization movement.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.290-294
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• 2006

Inactivation rates of Salmonella enteritidis in vitro and in vivo were assessed using confocal microscopy and flow cytometry. S. enteritidis was inactivated with 1% (w/v) trisodium phosphate (TSP) and live cells, and inactive cells were distinguished by staining with fluorescent probe, LIVE/DEAD BacLight Bacteria Viability stain. After TSP treatment for 1 min, most of Salmonella cells changed from green (live cells) fluorescence to red (inactive cells) fluorescence, indication of effective sanitizing. Inactivation efficiency and contamination sites of S. enteritidis on chicken skin by TSP treatment were assessed using confocal laser microscopy. Precise flow cytometry histograms for viability changes of S. enteritidis. after TSP treatments were obtained. Efficiency of various sanitizer treatments on foodborne pathogens could be assessed using this method.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.105-114
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• 2004

This study was performed to examine the physical and mechanical properties of eco-concrete using soil, natural coarse aggregate, soil compound and polypropylen fiber. The mass loss ratio was decreased with increasing the content of coarse aggregate and soil compound. The compressive strength, flexural strength, ultrasonic pulse velocity and dynamic modulus of elasticity were increased with increasing the content of coarse aggregate, soil compound and polypropylene fiber. The compressive and flexural strengths were showed in 8.07 MPa and 2.641 MPa at the curing age 28 days, respectively. The coefficient of permeability was decreased with increasing the content of coarse aggregate and soil compound, but it was increased with increasing the content of polypropylene fiber. The lowest coefficent of permeability was showed in $5.066{\times}10^{-9}cm/s$.

• Journal of Life Science
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• v.29 no.4
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• pp.410-420
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• 2019

Citrus unshiu peel extracts possess a variety of beneficial effects, and studies on their anticancer activity have been reported. However, the exact mechanisms underlying this activity remain unclear. In the current study, the apoptotic effect of ethanol extract of C. unshiu peel (EECU) on human breast adenocarcinoma MDA-MB-231 cells and related mechanisms were investigated. The results showed that the survival rate of MDA-MB-231 cells treated with EECU was significantly inhibited in a concentration-dependent manner, which was associated with the induction of apoptosis. EECU-induced apoptosis was associated with the activation of caspase-8 and caspase-9, which initiate extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3, a representative effect caspase. EECU suppressed the expression of the inhibitor of apoptosis family of proteins, leading to an increased Bax/Bcl-2 ratio and proteolytic degradation of poly (ADP-ribose) polymerase. EECU also enhanced the loss of the mitochondrial membrane potential and cytochrome c release from the mitochondria to the cytosol, along with truncation of Bid. In addition, EECU activated AMP-activated protein kinase (AMPK), and compound C, an AMPK inhibitor, significantly weakened EECU-induced apoptosis and cell viability reduction. Furthermore, EECU promoted the generation of reactive oxygen species (ROS), which acted as upstream signals for AMPK activation as pretreatment of cells, with the antioxidant N-acetyl cysteine reversing both EECU-induced AMPK activation and apoptosis. Collectively, these findings suggest that EECU inhibits MDA-MB-231 adenocarcinoma cell proliferation by activating intrinsic and extrinsic apoptotic pathways, which was mediated through ROS/AMPK-dependent pathways.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.439-446
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• 2005

Ferritin is known to be the principle iron-storage protein in a wide variety of rganisms. The electro­phoretic mobility and immunological cross-reactivity of dog splenic ferritin were compared with those of horse, bovine, and pig splenic ferritin after isolation using heat treatment, salting out, column chromatography, and ultrafiltration. These isolation methods allowed the recovery of $\~84{\mu}g$ of the ferritin per g of spleen. The iron content in the dog ferritin was $22.7\%$, which appeared to be higher than those in the other mammalian ferritins tested. The electrophoretic mobility of the dog ferritin under nondenaturing conditions was similar to its bovine counterpart, whereas it was more identical to pig and horse ferritins on an SDS-polyacrylamide gel. The molecular weight of the dog ferritin subunit was 19.5 kDa on an SDS-polyacrylarnide gel, and the subunit was unable to bind with iron. The polyclonal anti-dog ferritin raised in rats was able to cross-react with the pig, bovine, and horse ferritins, upon Ouchterlony double immunodiffusiion. A Western blot analysis also revealed that the anti-dog ferritin, which specifically bound with the dog ferritin subunit, could also recognize the horse, bovine, and pig ferritin subunits and the maximum cross-reactivity was exhibited with the pig ferritin subunit, indicating that the dog ferritin is immunochemically more similar to the pig ferritin than its other mammalian counterparts. Accordingly, these results elucidate the biochemical and immunochemical characteristics of dog ferritin that might have a potential to be applied as an oral iron supplement to treat iron deficiency anemia.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.15-24
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• 2021

This study was conducted to evaluate effects of microbial fertilizer (MF) containing Bacillus amyloliquefaciens on the growth in the lettuce by treating MF without and with organic fertilizer (OF), or by its formulation types, and to investigate its application in the eco-friendly agriculture. B. amyloliquefaciens, active microbe of MF, had activities of amylase and protease. Applied only MF without OF, MF treatments were not significantly different with non-fertilizer (NF). As compared to control, dry weight of MOF2 treatment (2,500 kg OF/ha + 50 kg MF/ha) was increased by about 30%. As applied with wettable powder type (WP) and soluble powder type (SP) of MF, the dry weight of WP was increased by 43% than that of control, but SP not significantly different. In the comparison with two MF formulation, dry weight of WP was increased by about 37% than that of SP. These results indicated that an application of MF improved the growth of lettuce by prompting a mineralization of OF, and that the formulation type of MF was better WP than SP.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.3
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• pp.10-17
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• 2016

This paper presents a laboratory validation of a new approach for Finite Element Model Updating(FEMU) on short-span bridges by combining ambient vibration measurements with static load input-deflection output measurements. The conventional FEMU approach based on modal parameters requires the assumption on the system mass matrix for the eigen-value analysis. The proposed approach doesn't require the assumption and even provides a way to update the mass matrix. The proposed approach consists of two steps: 1) updating the stiffness matrix using the static input-deflection output measurements, and 2) updating the mass matrix using a few lower natural frequencies. For a validation of the proposed approach, Young's modulus of the laboratory model was updated by the proposed approach and compared with the value obtained from strain-stress tests in a Universal Testing Machine. Result of the conventional FEMU was also compared with the result of the proposed approach. It was found that proposed approach successfully estimated the Young's modulus and the mass density reasonably while the conventional FEMU showed a large error when used with higher-modes. In addition, the FE modeling error was discussed.

• Journal of the Korean Geographical Society
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• v.44 no.4
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• pp.481-496
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• 2009

Every coastal area exhibits its own unique landscape owing to the combination of the natural and cultural processes. Coastal barrier islands well show the cultural aspects of American coastal landscapes. Some 47% of barrier island area was occupied by urban and built-up area in New Jersey, while some 5% in Georgia. Tourism-related development is back to in the mid 19C. in N.J. due to the closeness to heavily populated areas such as New York and Philadelphia. Developments without proper understanding the nature of coastal processes caused New Jerseyization, the destruction of the beauty or naturalness. It was mainly due to the lack of growth-control policies and the foresight for the future coast in the processes of legislation. North Carolina's islands experienced an increase of 269% in urbanized acreage between 1956 and 1976. However, N.C. exercised her wisdom to recover the naturalness of the coastal environs: all engineering structures are banned on the beaches. Nine out of 13 barrier islands in Georgia exist in the wilderness condition owing to her unique history. The remaining islands still experienced the least development. After the Civil War most of Georgian islands were owned by rich families and maintained as wilderness. In the 1970s most of the uninhabited islands were sold or donated to research institutes or governmental agencies.