• Journal of Plant Biotechnology
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• v.45 no.2
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• pp.146-153
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• 2018

Lilium ledebourii Bioss is a wild species of Lilium, which grows naturally in some provinces of Iran. Previous studies on Lilium tissue culture have been linked to direct regeneration and a few studies have been conducted on indirect regeneration, which has been studied under bright conditions. In this study, for the first time in the world, all the stages of indirect regeneration (callus induction, shoot and root induction) have been studied under dark conditions. Callus formation and the regeneration levels of L. Ledebourii Bioss were examined for three replicates in an MS (Murashige and Skoog) medium with different hormonal compositions and by using a factorial experiment in the framework of a completely random plan. For callus initiation, 2,4-D and kinetin hormones were used in five and four levels, respectively, as auxin and cytokinin. Results showed that the highest percentage of the callus was found in $3{\mu}M$ of 2,4-D and $0.5{\mu}M$ of kinetin. In terms of callus wet weight, the highest amount was found in $3{\mu}M$ of 2,4-D and $0.5{\mu}M$ of kinetin. In addition, in terms of diameter, the highest amount was found in $3{\mu}M$ of 2,4-D, and $0.5{\mu}M$ of kinetin. In summary, the 2,4-D hormone had a major impact on the percentage of regeneration increase so that the best response was related to the composition of $3{\mu}M$ of 2,4-D, and $0.1{\mu}M$ of kinetin. This study contended that auxin and cytokinin can induce long shoots and roots through cell elongation in dark condition.

• The Korean Journal of Cytopathology
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• v.7 no.1
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• pp.79-83
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• 1996

Gaucher's disease is an autosomal recessive disorder resulting from mutation at the glucocerebrosidase locus on chromosome 1q21. As a result, glucocerebroside accumulates principally in the phagocytic cells known as Gaucher cells. In our case, a five-year old girl was admitted with seven days' history of fever and abdominal distension. At physical examination the patient had hepatosplenomegaly. Laboratory tests revealed a hemoglobin concentration of 2.8g/L: platelet counts of $23,000/{\mu}l$: normal range of white cell and differential counts, and negative Coombs' test. Liver enzymes were normal. For the evaluation of hepatosplenomegaly, fine needle aspiration was performed blindly against the palpable spleen. Wet-fixed hematoxylin and eosin-stained smears are made. The smears from the spleen showed predominantly macrophages with abundant cytoplasm and rather small, uniform, often eccentric nuclei with small nucleoli. The multinucleated cells were often found. The cytoplasm was pale, with more or less distinct fibrillarity. The cells had the characteristic appearance of Gaucher cells. Gaucher cells were also found in the tissue section from the liver, spleen and lymph node and the bone marrow aspirate. The diagnosis was later confirmed by determination of bela-glucosidase activity in peripheral blood leucocytes. Fine needle aspiration of the spleen is considered as a convenient procedure with a low complication rate for the diagnosis of lysosomal storage disease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.170-174
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• 2005

Barley plants growing in the wet paddy field easily encounter suboptimal oxygen concentration in the rhizosphere that causes molecular oxygen deficiency in root cells. The capacity of root cells to utilize energy sources is known to be positively related to resistance to hypoxia stress. This study was conducted to investigate effects of hypoxia on enzymes involved in the starch and sucrose metabolism. Barley seedlings at the third leaf stage were subjected to hypoxia (1 ppm dissolved oxygen) by purging the culture solution with nitrogen gas for up to seven days. The protein content was slightly decreased by hypoxia for 7 days. $\alpha-Amylase$ activities increased significantly in the root but not in the shoot after 3 to 7 days of hypoxia. $\beta-Amylase$ activities were not affected significantly in both tissues. Additionally, sucrose synthase activities were affected little in both tissues by 7 days of hypoxia. The results indicate that root cells activate break­down of polysaccharide reserves in response to an acute hypoxia to supply energy sources for fermentative glycolysis and cell wall fortification.

• Advances in concrete construction
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• v.2 no.2
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• pp.109-123
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• 2014

This paper presents chloride induced corrosion durability of reinforcing steel in geopolymer concretes containing different contents of sodium silicate ($Na_2SiO_3$) and molarities of NaOH solutions. Seven series of mixes are considered in this study. The first series is ordinary Portland cement (OPC) concrete and is considered as the control mix. The rest six series are geopolymer concretes containing 14 and 16 molar NaOH and $Na_2SiO_3$ to NaOH ratios of 2.5, 3.0 and 3.5. In each series three lollypop specimens of 100 mm in diameter and 200 mm in length, each having one 12 mm diameter steel bar are considered for chloride induced corrosion study. The specimens are subjected to cyclic wetting and drying regime for two months. In wet cycle the specimens are immersed in water containing 3.5% (by wt.) NaCl salt for 4 days, while in dry cycle the specimens are placed in open air for three days. The corrosion activity is monitored by measuring the copper/copper sulphate ($Cu/CuSO_4$) half-cell potential according to ASTM C-876. The chloride penetration depth and sorptivity of all seven concretes are also measured. Results show that the geopolymer concretes exhibited better corrosion resistance than OPC concrete. The higher the amount of $Na_2SiO_3$ and higher the concentration of NaOH solutions the better the corrosion resistance of geopolymer concrete is. Similar behaviour is also observed in sorptivity and chloride penetration depth measurements. Generally, the geopolymer concretes exhibited lower sorptivity and chloride penetration depth than that of OPC concrete. Correlation between the sorptivity and the chloride penetration of geopolymer concretes is established. Correlations are also established between 28 days compressive strength and sorptivity and between 28 days compressive strength and chloride penetration of geopolymer concretes.

• Journal of Korean Academy of Nursing
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• v.36 no.3
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• pp.523-531
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• 2006

Purpose: The purpose of this study was to examine the effects of the ulmus root-bark dressing on tissue regeneration in experimentally-induced pressure ulcers in rats. Method: A randomized pretest/post-test control group time-series study design was used. Thirty-three male Sprague-Dawley rats were used in this study. The rats were anesthetized with 100mg/kg of ketamine. Pressure ulcers were induced at 140mmHg for three hours using a personally-designed pressing apparatus. For four weeks, the ulmus root-bark dressing was applied every other day in the experimental group (n=18) and a wet gauze dressing in the control group (n=15). For data analysis, the statistical program SPSS WIN 12 was used. The wounds were examined by light microscopy andelectron microscopy. Result: There were significant statistical differences in the size of the pressure ulcers as time went by(p=0.006). It should be noted that there were no significant statistical differences in the number of capillaries. Using light microscopy the inflammatory infiltration and neovascularization in the dermis in the experimental group emerged densely in the early stages, but recovered rapidly at the latter stages. In addition, the reepithelization of the epidermis occurred earlier than in the control group. By electron microscopy, the cell organelles of the capillary endothelial cells and the basal lamina of capillaries in the experimental group showed a more rapid maturation during the latter stages, compared with the control group. Conclusion: According to this study, it can be concluded that the ulmus root-bark dressing is effective regarding the healing of pressure ulcers.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.7
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• pp.721-730
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• 2012

The present paper presents a numerical study on multiphase flows induced by wall adhesion. The continuum surface force (CSF) model with the wall adhesion boundary condition model is used for calculating the surface tension force; this model is implemented in an in-house solution code (PowerCFD). The present method (code) employs an unstructured cell-centered method based on a conservative pressure-based finite-volume method with a volume capturing method (CICSAM) in a volume of fluid (VOF) scheme for phase interface capturing. The effects of wall adhesion are then numerically simulated by using the present method for a shallow pool of water located at the bottom of a cylindrical tank with no external forces such as gravity. Two different cases are computed, one in which the water wets the wall and one in which the water does not wet the wall. It is found that the present method efficiently simulates the surface tension-dominant multiphase flows induced by wall adhesion.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.267-274
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• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.

• Journal of Sensor Science and Technology
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• v.20 no.3
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• pp.207-212
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• 2011

In this study, pyramid structured black silicon process was developed in order to overcome disadvantages of using wet etching to texture the surface of single crystalline silicon and using grass/needle-like black silicon structure. In order to form the pyramidal black silicon structure on the silicon surface, the RIE system was modified to equip with metal-mesh on the top of head shower. The process conditions were : $SF_6/O_2$ gas flow 15/15 sccm, RF power of 200 W, pressure at 50 mTorr ~ 200 mTorr, and temperature at $5^{\circ}C$. The pressure did not affect the pyramid structure significantly. Increasing processing time increased the size of the pyramid, however, the size remained constant at 1 ${\mu}M$ ~ 2 ${\mu}M$ between 15 minutes ~ 20 minutes of processing. Pyramid structure of 1 ${\mu}M$ in size showed to have the lowest reflectivity of 7 % ~ 10 %. Also, the pyramid structure black silicon is more appropriate than the grass/needle-like black silicon when creating solar cells.

• Journal of Aquaculture
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• v.10 no.3
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• pp.227-237
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• 1997

Five species of intertidal clams including Ruditapes philippinarum, Tegillarca granosa, Solen strictus, Heteromacoma irus, and Coecella chinensis were tested for the presence of the protozoan parasite, Perkinsus sp. using fluid thioglycollate medium (FTM) fortified with antibiotics and histological techniques. Each individual clam was placed in a test tube filled with 10ml FTM, placed in totally dark place, and incubated over a week. After incubation the clam tissues were stained with Lugol's iodine solution and examined under a light microscope to find out any hypnospores of Perkensus sp. in the tissues. Cross-sections of the clams were also embedded in paraffin, sliced to 3um, and stained with Harry's hematoxylene and Picro eosine to observe the presence of tomont or trophozoites. Perkinsus sp. were found in the presence of tomont or trophozoites. Perkinsus sp. were found in the tissues of R. philippinarum collected from Kangjin and Wando, along the south coast of Korea. However, Perkinsus sp. was not found in four other species of clams nor R. philippinaurm collected from Kimnyong and Waido in Cheju. A size-dependent Perkinsus sp. infection was found in R. philippinarum collected rom Kangjin and Wando the clams smaller than 15mm in shell width do not exhibit and Perkinsus sp. while other clams greater than 20mm in shell width exhibit almost 100% infection. To determine the number of Perkinsus sp. in the clams, FTM cultured clam tissues were digested with 2M NaOH solution and the number of hypnospores in the tube were counted. The number of hypnospores counted from the tissues indicated that each Manila clam contains 100,000 to 3,500,000 Perkinsus cells or 20,000 to 1,000,000 cells per gram tissue wet weight. The results of cell counts also suggests that such a high occurrence of Perkinsus sp. in the clam may cause mortality, as already reported from other studies of Perkinsus spp.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.22-28
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• 2008

Cutting oils are emulsionable fluids widely used in metal working processes. Their composition is mineral oil, water, and additives (fatty acids, surfactants, biocides, etc.) generating a toxic waste after a long use. Cutting oils also affect colour, taste and odour of water, making it undesirable for domestic and industrial uses. In these days, conventional treatment methods as evaporation, membrane separation or chemical separation have major disadvantages since they generate a concentrated stream that is more harmful than the original waste. In this study, our purpose is to reduce cutting oils by using biological treatment. Eighty one strains were isolated from cutting waste oil of industrial waste water sludge under aerobic conditions. Among these strains, KS47, which removed 90.4% cutting oil in 48 hr, was obtained by screening test under aerobic conditions(pH 7, $28^{\circ}C$). KS47 was identified as Pseudomonas aeruginosa according to morphological, physiological and biochemical properties, 16S rDNA sequence, and fatty acid analysis. P. aeruginosa KS47 could utilize cutting oil as carbon source. In batch test, we obtained optimal degradation conditions(1.5 g/L cell concentration, pH 7, and temperature $30^{\circ}C$). Under the optimal conditions, 1,060 mg/L cutting oil was removed 83.7% (74.1 mg/L/hr).