• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.15-22
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• 1988

Factors affecting the regeneration, reversion of protoplasts from mycelium of F. velutipes were investigated and the selection of auxotrophic mutants from protoplasts of F. velutipes was performed. PDP medium stabilized with 0.6M sucrose was suitable for the regeneration of protoplasts, and regeneration frequency was 0.47-1.32. The regeneration frequency of protoplasts was increased when nutrients were added to the regeneration medium. Especially, yeast extract was the most effective to regeneration of protoplasts. Regeneration pattern of protoplasts was formation of germ tubes from bud-like cells. 13-18% of monokaryotic strains was appeared from reverted protoplasts. Five of auxotrophic mutants were isolated from strains showed survival frequency of 1.9-16.

• Journal of Chest Surgery
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• v.17 no.1
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• pp.157-166
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• 1984

These biologic test procedures are designed to test the suitability of P.V.C. made in Korea intended for parenteral preparation, which were based on the U.S. Pharmacopeia XIX "Biologic Test-Plastic Container", Official from July 1, 1975. Healthy adult human blood and rabbits weighing 2\ulcorner.2Kg were used for test materials. Sample P.V.C. were sampled from the medical equipments made in Korea randomly and Control P.V.C. were sampled from the standardized Cobe and Polystan P.V.C. tubes. P.V.C. extract was prepared from a homogeneous P.V.C. samples by incubating 60 square centimeters of the sample per 20 millimeters of sterile pyrogen-free saline at 70\ulcorner for 72 hours or autoclaving at 120\ulcorner for 1 hour. The Implantation Test was designed to evaluate the reaction of living tissue to the plastic by the method of the implantation of the Sample itself into animal tissue. The Systemic Injection Test, the Intracutaneous Test, and the remainders were designed to determine the biological response of animals to plastics by the single-dose injection of specific extracts prepared from a Sample. The results are as follows; 1.Implantation Test - No significant difference for reactions was noted between the Sample treated animal and the Control after 72 hours of implantation. 2.Systemic Toxicity Injection Test - No sign of toxicity and/or death immediately after injection and at 4, 24, 48 hours respectfully after injection. 3.Intracutaneous Test - None of the animals treated with the Sample showed a significantly greater reaction than the observed in the animals treated with Blank. 4.Pyrogen Assay-Only one animal treated with the Sample showed the maximal rise of rectal temperature about 0.2\ulcorner after 3 hours of injection, but remainders showed no change. 5.Hemolytic Index - The positive Control tube of distilled water exhibited complete hemolysis while the negative Control tube and P.V.C. extract were negative demonstrating no hemolysis. 6.Cell Morphology of Erythrocytes and Leukocytes on Stored, Heparinized Human Blood -- There was no significant difference in the morphology of either the Control or Sample extract. 7.Clotting Mechanism of Human Blood in vitro - After allowing to the P.V.C. extract at room temperature for 5 Hours and at 10\ulcorner for 24 hours, there was no appreciable difference in Prothrombin Time under these conditions. 8.Clotting Mechanism of Rabbit in vivo - At the termination of 5 days after intraperitoneal injection of the P.V.C. extract, no significant changes in Clotting Time were observed. According to the above results, it could be concluded that the P.V.C. made in Korea was acceptable for parenteral preparation, especially treated with physiologic saline and/or human blood.man blood.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.517-524
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• 2018

This purpose of this research is to observe the influence of non-condensable gas (NCG) on a horizontal super-hydrophobic aluminum tube and compare it with a bare aluminum tube. To achieve super-hydrophobic characteristics, an aluminum tube was coated with a Self-Assembled Monolayer (SAM). The overall heat transfer coefficient U was used to represent the condensation performance. The NCG mass fraction was the main variable, and its range was 0.08 to 0.45. The condensation performance of the SAM tube and bare tube increased with decreasing mass fraction of NCG. The SAM tube showed 1.9 to 2.5 times larger dropwise condensation performance than the bare tube. When the mass fraction of NCG decreased in the SAM tube, the rate of increase of the SAM tube was lower because flooded condensation occurred. In addition, filmwise condensation occurred in the SAM tube when more active condensation was generated, and its performance was lower than that of the bare aluminum tube. The flooded and filmwise condensation in the SAM tube is explained by the pinning effect. In conclusion, controlling the condition of the condenser is necessary to improve the condensation performance by surface modification a SAM.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.220-230
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• 2014

BACKGROUND: Excessive metals in the soil have become one of the most significant environmental problems. Phytoremediation has received considerable attention as a method for restoring the contaminated soils. The microbes having remarkable metal tolerance and plant growth-promoting abilities could also play a significant role in remediation of metal-contaminated soils, because bioaugmentation with such microbes could promote phytoextraction of metals. Therefore, the present study was focused on evaluating the phytoextraction of heavy metals (Co, Pb and Zn) in Helianthus annuus (sunflower) induced by bioaugmentation of a phosphate solubilizing bacterium. METHODS AND RESULTS: A phosphate solubilizing bacterium was isolated from metal-contaminated soils based on the greater halo size (>3 mm) with solid NBRIP agar medium containing 10 g glucose, 5 g $Ca_3(PO_4)_2$, 5 g $MgCl_2{\cdot}6H_2O$, 0.25 g $MgSO_4.7H_2O$, 0.2 g KCl, 0.1 g $(NH_4)_2SO_4$ in 1 L distilled water. Isolated bacterial strain was assessed for their resistance to heavy metals; $CoCl_2.6H_2O$, $2PbCO_3.Pb(OH)_2$, and $ZnCl_2$ at various concentrations ranging from $100-400{\mu}g/mL$ (Co, Pb and Zn) using the agar dilution method. A pot experiment was conducted with aqueous solutions of different heavy metals (Co, Pb and Zn) to assess the effect of bacterial strain on growth and metal uptake by Helianthus annuus (sunflower). The impact of bacterial inoculation on the mobility of metals in soil was investigated under laboratory conditions with 50 mL scaled polypropylene centrifuge tubes. The metal contents in the filtrate of plant extracts were determined using an atomic absorption spectrophotometer (Perkinelmer, Aanalyst 800, USA). CONCLUSION: Inoculation with Enterobacter ludwigii PSB 28 resulted in increased shoot and root biomass and enhanced accumulation of Co, Pb and Zn in Helianthus annuus plants. The strain was found to be capable of promoting metal translocation from the roots to the shoots of H. annuus. Therefore, Enterobacter ludwigii PSB 28 could be identified as an effective promoter of phytoextraction of Co, Pb and Zn from metal-contaminated soils.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.381-391
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• 1999

A new 5th generation adhesive system(ONE-STEP) has been supplied which operators can apply to conditioned tooth surfaces by one simplified step. The purpose of this study was to determine whether different methods of adhesive application and various air drying duration after applying adhesive affect the shear bond strength of composite resin to dentin, and to evaluate the adhesive pattern of composite resin and dentin under SEM. Seventy-seven extracted human molar teeth were cleaned and mounted in palstic test tubes. The occlusal dentin surfaces were exposed with Diamond Wheel Saw and smoothed with Lapping and Polishing Machine (South Bay Technology Co., U.S.A.). Teeth were randomly divided into 7 groups (n=11), In experimental A group, adhesive was applied to dentin with agitation for 20 sec. In experimental N-A group, adhesive were continuously applied to dentin for 20 sec. Also control and experimental 1, 2, 3, 4 groups were dried for 10, 0, 5, 20, 30 seconds after applying adhesive, respectively, Adhesives were light cured for 10 sec. A gelatin capsule 5mm in diameter was filled with Aelitefil$^{TM}$ composite resin, placed on the treated dentin surface and light cured for 40 see, from three sides, All specimens were stored in distilled water at room temperature for 24 hours. The shear bond strengths were measured using a universal testing machine(AGS-1000 4D, Japan) at a crosshead speed of 5mm/min. An one-way ANOVA and LSD test were used for statistical analysis of the data. For SEM evaluation, seven specimens were made and sectioned. Representive postfracture and seven specimens were mounted on brass stubs, sputter-coated with gold and observed under SEM. The results were as follows : 1. The shear bond strength of experimental A group which adhesive were applied to dentin with agitation was higher than that of experimental N-A group (continuous application), and there was significant difference between two groups (p<0.01). 2. The interface between composite and dentin according to different application methods showed close adaptation in experimental A group and showed tinny gap in experimental N-A group. 3. The shear bond strength accoding to various air drying duration was the lowest value(7.57${\pm}$2.60 MPa) in experimental 1 group, so there was significant difference between experimental 1 group and other four groups (p<0.05). But there was no significant difference of shear bond strength between four groups (p>0.05). 4. The interface between composite and dentin according to various air drying duration showed close adaptation in control group and tinny gap in experimental 3 and 4 groups. But experimental 1 and 2 groups showed $30{\mu}$ and 6 - $10{\mu}m$ thick gaps, respectively.

• Journal of the Korean Society of Radiology
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• v.8 no.4
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• pp.211-216
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• 2014

Radium is rock or soil of crust or uranium of building materials after radioactivity collapse process are created colorless and odorless inert gas that accrue well in sealed space like basement. It inflow to lung circulate respiratory organ and caused lung cancer because of deposition of lung or bronchial tubes. In this study, the air in the elementary school classroom nongdoeul tonkatsu place of measured values were compared using the calculated annual internal radiation exposure. La tonkatsu exposure measured in primary school classroom at least five schools when you close the windows in the average floor 0.56mSv 2 floors ground floor windows when opened 0.384mSv 048mSv 3 floors, 2 floor levels of the same three layers 0.31mSv 0.296mSv the human exposure to radon and radiation on the first floor of 3 floors above ground in a lot of exposure was moderate. When you close the window from the first floor up 0.384mSv 056mSv 3 floors with a minimum annual radiation exposure due to natural radiation in the 16 to 23.3 percent minimum 2.4mSv accounted for. When I opened the window to the maximum annual radiation exposure 2.4mSv 0.296mSv 0.31mSv least a minimum of 12.3 to 12.91% accounted for Results suggest that more than five chodeunghakgyoeun La tonkatsu domestic radon measurements conducted below regulatory requirements and internal exposure has also fall within the normal range. People The less the radiation exposure to the human body because it reduces the impact in the classroom in elementary school vent windows often reduced to the maximum radon concentration in the air, if called tonkatsu be able to reduce radiation exposure for the immune system is weak and elementary will be helpful to experiment more in the future for the school authorities called tonkatsu investigation is done to him if the action to establish a more secure school building facilities is thought would be helpful.