• Horticultural Science & Technology
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• v.28 no.5
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• pp.777-782
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• 2010

This research tested five modified Hoagland solutions for proper fertility management of nitrogen in 'Seolhyang' strawberry cultivations. The changes of nutrient solutions were in total nitrogen concentrations ($meq{\cdot}L^{-1}$) such as 0 (${NO^-}_3$), 2.5 (${NO_3}^-$), 5 (${NO_3}^-$), 10 ($7.5{NO_3}^-$ + $2.5{NH_4}^+$) and 15 ($10{NO_3}^-$ + $5{NH_4}^+$). The fresh weight and $NO_3$-N concentrations in petiole sap responded to the elevated nitrogen concentrations in fertilizer solution in quadratic (y=7.10+2.668x-$0.115x^2$, $R^2=0.7983^{***}$) and linear (y=26.14+5.245x, $R^2=0.6083^{***}$), respectively. The dry weight and N content of the above ground plant tissue responded to the elevated nitrogen in quadratic (y=2.140+0.492x-$0.022x^2$, $R^2=0.6110^{***}$) and linear (y=0.569+0.033x, $R^2=0.6952^{***}$), respectively. In our experiment the solution with $5meq{\cdot}L^{-1}$ of ${NO_3}^-$ showed positive results in both dry and fresh weight productions. However, a future research about modification of this solution and growth and nutrient uptake response is necessary to achieve better growth of 'Seolhyang' strawberry.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.698-705
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• 1994

The basic medium oil modified alkyd resin was synthesized from linseed oil fatty acid(LOFA), phthalic anhydride(PAA), maleic anhydride(MA) and trimethylol propane(TMP) by condensation polymerization at $230^{\circ}C$. MA/TMPTA modified water-reducible alkyd resins were synthesized with TMPTA graft copolymerization onto the basic resin at $180^{\circ}C$. Acid value of the resin was controlled by the addition amount of MA and N,N-dimethylethanol amine(DMEA) was used as a neutralizing agent to prepare of the water-reducible alkyd resin. The effect of TMPTA on the graft copolymerization of the resin was studied by measuring molecular weight glass transition temperature(Tg), viscosity, graft efficiency, and gel contents of melanin cured film. Heat resistance, UV resistance and water resistance of cured film of MA/TMPTA modified resin was compared to those of TMA/TMPTA modified alkyd resin. The molecular weight, viscosity gel contents and graft efficiency of water reducible alkyd resin were increased according to the TMPTA graft copolymerization, but Tg was decreased. The viscosity was lower when the solid contents reached 40% than that of 30% content and also and also became lower with the extent of neutralization ratio, The heat resistance, UV resistance and water resistance of the MA/TMPTA modified alkyd resis were better than those of TMA/TMPTA modified alkyd resin but the storage stability of the TMA/TMPTA alkyd resis was better than that of MA/TMPTA modified alkyd resin.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.334-340
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• 2020

In this study we developed an enrichment medium and lysis buffers to detect Listeria monocytogenes in meat and processed meat products under various lysis conditions. The enrichment efficiency of L. monocytogenes medium listed in the Food Standards was compared, and thus, Listeria Enrichment Broth (LEB) was modified by adding supplements such as carbon source and minerals. The lysis buffers were developed to extract L. monocytogenes DNA quickly and efficiently under various lysis conditions. L. monocytogenes was most rapidly grown in LEB containing 0.1% pyruvate and 0.1% ferric citrate. A lysis buffer mixed with 0.5% or 1% N-lauroylasrcosine sodium salt, 0.5 N NaOH and 0.5 M EDTA for 30 min at room temperature was found to be the best in terms of DNA purity and yield. These results indicate that developed enrichment medium and lysis buffer can be used to detect L. monocytogenes in meat and processed meat products rapidly and efficiently.

• Journal of Life Science
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• v.20 no.11
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• pp.1577-1581
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• 2010

Granulocyte colony stimulating factor (G-CSF) is a hematopoietic cytokine that stimulates bone marrow cells to proliferate and differentiate into granulocytes. G-CSF is approved and used for therapeutic purposes. The endoplasmic reticulum (ER) signal peptide of hG-CSF was replaced with silkworm-specific signal peptides to express and efficiently secrete recombinant hG-CSF by silkworm cells. Plasmids that contain cDNAs for hG-CSF and hG-CSF fused with silkworm- specific signal peptides of prophenoloxidase activating enzyme (PPAE), protein disulfide isomerase (PDI), and bombyxin (BX) were constructed. The G-CSF protein was expressed in insect cell line BM5 and was detected by western blot analysis. The cells transfected with plasmids containing rhG-CSF genes with silkworm-specific signal sequences released mature rhG-CSF protein more efficiently than the cells transfected with pG-CSF, the plasmid containing human G-CSF gene, including its own signal sequence. The production of hG-CSF reached maximal level at four days post-transfection and remained at a high level until 7 days post-transfection. These data demonstrate that the modification of the human G-CSF mimic to insect proteins synthesized in ER greatly improves the production of the protein.

• Journal of Life Science
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• v.27 no.7
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• pp.840-848
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• 2017

Proper intracellular transport is essential for normal cell function. Intracellular transport is mediated by microtubule-dependent molecular motor proteins, as well as kinesin and cytoplasmic dynein, which move their cargo along long, microtubule tracks in cells. Kinesins are ATP-dependent plus-end-directed motor proteins in the intracellular transport of organelles, vesicles, RNA complexes, and protein complexes. The mislocalization of these different types of cargo has been linked to cell dysfunction and degeneration. The cargo transport of kinesins can be described by the following steps: binding to the appropriate cargo and/or adaptor proteins, activation of the kinesin's motility and movement along the microtubule, and the release of the cargo at the correct destination. Recently, several studies have revealed the mechanisms for the regulation of kinesin motor activity, including cargo loading and unloading. Intracellular cargo transport is also modulated by adaptor proteins, which link the kinesins to their cargo. The regulatory proteins, which include protein kinases and phosphatases, regulate kinesin motor activity directly through the phosphorylation or dephosphorylation of kinesins and indirectly through the modification of adaptor proteins, such as c-Jun NH-terminal kinase-interacting proteins, or of the microtubule network. These findings lay the groundwork for understanding how kinesins are differentially engaged in intracellular cargo transport. In addition, understanding the regulatory mechanisms of each kinesin is an area of key interest within cell biology and neurophysiology. In this study, we reviewed kinesins' regulation proteins and discuss how their regulation affects cargo recognition and transport.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.4
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• pp.70-77
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• 2010

Microcement grouting and micro pile are frequently used for ground modification during tunnel construction. The influence of grouting pressure of microcement grouting and micro pile to the existing bridge which is directly over the constructing tunnel is investigated. Three dimensional seepage flow-structure interactive analysis considering firm water pressure with full stages of construction including the construction of upper bridge, microcement grouting, micro pile and tunnel is performed. The settlement and tilting of the pier of existing bridge violate the design code and the reaction of the bridge are highly increased after grouting. The stress of tunnel bracings such as rockbolt and shotcrete also exceed the limit of the code. The pressure of microcement grouting is confined by bedrock and transmit to the surrounded soil and the upper bridge. Microcement grouting needs mid-high pressure to penetrate through weak fault plane and the pressure greatly influence the safety of the upper structure. It is important to decide and care the grouting pressure to improve weak fault plane directly under the existing structures and the pressure of microcement grouting should be considered in underground analysis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.1-9
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• 2017

Spiral reinforcement in a circular column plays an effective role in the ductile behavior of a column through position fixing and buckling restraining of the longitudinal reinforcement, and confining core-concrete. Each country has suggested the minimum volumetric ratio of spiral reinforcement in order to secure the ductility of concrete columns. The minimum volumetric ratio of spiral reinforcement suggested by ACI 318-14 and the national concrete structure design standard was developed based on the theory of Richard et al. (1928); furthermore it has been used until now. However, their theory cannot consider the effects of high strength concrete and high strength reinforcement, and arrangement condition of the spiral reinforcement. In this study, a modified minimum volumetric ratio equation is suggested, which is required to improve the ductility of reinforced concrete circular columns and to recover their stress. The modified minimum volumetric ratio equation suggested here considers the effect of the compressive strength of concrete, the yield strength of spiral reinforcement, the cross sectional area of columns, the pitch of spiral reinforcements and the diameter of spiral reinforcement. In this paper, the validity of the minimum volumetric ratios from ACI 318-14 and this study was investigated and compared based on the results of uniaxial compression experiment for specimens in which the material strength and the spiral reinforcements ratio were used as variables. In the end of the study, the modification method for the suggested equation was examined.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.272-277
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• 1990

Some additives were applied to improve Yukwa(Popped rice snack) quality and process modifications were tested for cutting down soaking time and application of rice flour. Addition of soaked soybean (3%, w/w) to dough showed higher expansion rate and better physical properties with more acceptable quality by sensory evaluation of Yukwa. Baking powder, modified starch and alcoholic liquor, Mackeali(rice wine, turbid). Soju(distilled liquor) and Yakju(rice wine, clear), were no positive effect on quality of Yukwa but alcoholic liquor gave more fine texture than others. High temprature soaking $(60^{\circ}C)$ of rice for 3 hours which is near gelatinization temperature of rice starch. gave same quality of Yukwa comparing with long time soaking (12 hours) at room temperature. Extention of high temperature soaking (12 hours) did not improve the quality of Yukwa. The 100 mesh of rice flour by dry milling method was better in expansion rate and hardness than 40 and 80mesh but it was worse than ordinary wet milling. It was notified that milling method and milling mechines for Yukwa preparation should be studied in more detail.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.3
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• pp.238-244
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• 1990

The behavior of conger eel, Astroconger myriaste(Brevoort), to the net pots with baits was investigated alternately in two experimental water tanks. One of the pots being dropped on the tank bottom, the eels increased rapidly in number of touching the pot to show a maximum whithin 30 minutes and then decreased gradually. The enterings of eels into the pots were also made mainly within 30 minutes and easier in pots with lower entrances. But the complete enterings were decided by the passage of eel tails through the pot entrances and so the eels retreated frequently after attemping to enter the pots, especially in pots small in the interval between the entrances and the baits or in pots with flappers. However, most of enterings encouraged the touches and earlier enterings ascribed earlier production of maximum touch. The eels, if entered the pots without flappers, got out of the pots relatively easily and the getting-out was easier in pots with lower entrances. On the other hand, the eels entered the pot with flappers could not get out of the pots. A comparison between the circular and square pots gave that the guidance of eels to the entrances was easier in the former and the passing of eels through the entrances in the latter, not only at the inside of pots but also at the outside. The general behavior of eels in touching or entering the net pots in the above results was almost equal to that on the bamboo and plastic pots in the previous paper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.5
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• pp.345-355
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• 1991

In order to effectively utilize the by-products of sea-food, the utilization of enzyme-modified flounder(Limanda aspera) skin gelatin as an emulsifier was investigated. In the experiment, the gelatin was extracted from the flounder skin with the heat-treatment at $60^{\circ}C$ and in pH 5.0 for 3 hrs with four volumes of distilled water and emulsifiers were enzymatically modified L-leucine alkyl esters$(L-leucine-OC_n$ : n= 2, 4, 6, 8 and 10) to the gelatin$(EMFSG-C_2,\;EMFSG-C_4,\;EMFSG-C_6,\;EMFSG-C_8,\;EMFSG-C_{10})$ for improving the functional properties such as emulsifying activity, emulsifying viscosity, whippability, electric conductivity, critical micelle concentration and interface tension, etc. Also, the functional properties of the L-leucine alkyl ester modified gelatins were compared with those of Tween-60 as reference. Molecular weights of the enzymatically modified flounder skin gelatin(EMFSG) were 20.5kDa. in $EMFSG-C_2.\;19.5 kDa.\;in\;EMFSG-C_4\;and\;16.5kDa.\;in\;EMFSG-C_6,\;EMFSG-C_8$ and $EMFSG-C_{10}$. respectively. Emulsifying activity and emulsifying viscosity in the modified gelatins were risen with increase of carbon number of the introduced L-leucine alkyl esters. Among the modified gelatins, $EMFSG-C_6$ exhibited the highest emulsifying stability and foaming stability, whereas $EMFSG-C_8$ showed the highest whippability. The electric conductivities of the all $EMFSG-C_n$ were linearly risen to critical micelle concentration(CMC) , therefore $EMFSG-C_{10}$ exhibited the lowest CMC value and interface tension, and dense particles in the microscopic observation. In conclusion, the best quality in functional properties was assured on $EMFSG-C_{10}$.