• Korean journal of applied entomology
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• v.54 no.4
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• pp.369-374
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• 2015

Grapholita molesta (GM) has been considered as a major problem to apple and peach orchards. Mating disrupters have been applied to control the pest over the world as an Integrated Pest Management [IPM] tool. Various types of dispensers releasing mating disrupters have been developed with different formulation of wax, polyethylene tube and aerosol. In this study, the dispensers that were composed of ester waxes and polypropylene (PP) film were used as dispenser materials to analyze release pattern of GM pheromone compared with paraffin wax and polyethylene (PE) film. The release pattern in PP film group was consistent with time while PE film group irregular. Based on these results, Japan wax_PP film dispenser (Japan_PP) was manufactured and showed the mating disruption effect of 98% during 5months in peach orchard.

• Journal of Aquaculture
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• v.21 no.1
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• pp.34-40
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• 2008

This study investigated the effect of rearing conditions on the spawning habit, juvenile growth and larvae development of Marphysa sanguinea, to develop techniques of its artificial seed production. M. sanguinea released trochophore larvae around the burrow when the water temperature was from $18^{\circ}C$ to $22^{\circ}C$. Larvae floated away after staying in the burrow for a while. Larvae secreted mucus eight days after release, covering their whole body with it, and developed ten somites 20 days after release. In preference of juveniles in different grain sizes of sediment, the highest survival rate was made in the grain substrate of $1{\sim}2$ mm in the mean diameter, but the lowest was in the $2{\sim}3$ mm grain substrate. Optimum growth was obtained at the rearing temperature of $24^{\circ}C$(SGR 1.10%), and it reached over $2{\sim}3$ times higher weight gain and specific growth rate than those reared at $21^{\circ}C(0.64),\;18^{\circ}C(0.56)$ and $15^{\circ}C$(0.42) for 50 days. Salinity also made a great difference in the growth and survival rate. The highest weight gain and growth rate were shown when the juveniles were reared at salinity 30 psu.

• Polymer(Korea)
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• v.37 no.1
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• pp.61-65
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• 2013

In this work, the anodic oxidation of carbon fibers was carried out to enhance the mechanical interfacial properties of carbon fibers-reinforced epoxy matrix composites. The surface characteristics of the carbon fibers were studied by FTIR, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Also, the mechanical interfacial properties of the composites were studied with interlaminar shear strength (ILSS), critical stress intensity factor ($K_{IC}$), and critical strain energy release rate ($G_{IC}$). The anodic oxidation led to a significant change in the surface characteristics of the carbon fibers. The anodic oxidation of carbon fiber improved the mechanical interfacial properties, such as ILSS, $K_{IC}$, and $G_{IC}$ of the composites. The mechanical interfacial properties of the composites anodized at 20% sulfuric/nitric (3/1) were the highest values among the anodized carbon fibers. These results were attributed to the increase of the degree of adhesion at interfaces between the carbon fibers and the matrix resins in the composite systems.

• Journal of Adhesion and Interface
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• v.13 no.1
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• pp.17-23
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• 2012

A fragrant microcapsule was prepared for use by students to reduce the stress of taking examinations. Rosmarinic acid was used as a fragrant oil which had the effect of relaxing stress, polycaprolactone (PCL) was used as a capsule wall material, and poly(vinyl alcohol) (PVA) as a stabilizer. The solvent evaporation method was used to form the microcapsule. The microcapsules were prepared by changing the stirring rate, the concentration of the stabilizer, and the molecular weight of PCL. The shape of the microcapsule was characterized by scanning electron microscopy (SEM). The size of the microcapsule was reduced by increasing the stirring speed. The release rate of rosmarinic acid was decreased when the higher molecular weight PCL was used. When the prepared microcapsule was tested in an aromatherapy class, the microencapsulated fragrant oil had a longer release time than the original fragrant oil. The study data showed that this fragrant oil was effective for increasing concentration ability, reducing stress, increasing digestive power, and increasing memory for the students.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.1
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• pp.15-23
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• 2008

This study is on encapsulation of a new whitening agent, LA-PEG using solid lipid nanoparticle(SLN) method, one of nanoparticle preparation method. Classical method has high capsulation efficiency for hydrophobic compounds but has demerit of low capsulation efficiency($2{\sim}3%$) for hydrophilic compounds. Purpose of this study is preparation of SLN that has higher skin penetration effect compared with general liposome, and also has higher encapsulation efficiency of hydrophilic compounds. For SLN preparation, coconut oil, macadamia oil, and jojoba oil were used. As a result, SLN preparation using coconut oil(include LA-PEG) has the most high encapsulation efficiency and also has the smallest average particle size(270 nm). SLN prepared with macadamia oil and 1% of Tween 60 has the largest particle size. Base made with coconut oil and 2% of Tween 60 showed the fastest release and base made with macadamia oil and 2% of Tween 20 showed the latest release.

• Journal of Wetlands Research
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• v.21 no.4
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• pp.334-343
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• 2019

A lab-scale vertical flow subsurface (VFS) wetland composed of three parallel columns with polypropylene synthetic fiber as main substrate was operated. Piggery stormwater diluted from swine excreta was fed to the wetland on the basis of three different hydraulic regimes or hydraulic retention time (HRT) of 2, 4, and 8 days with daily internal recirculation. Then, monitoring of common water quality parameters was carried out. Unexpectedly, an increase of effluent COD concentration accompanying the appearance of foams was observed during a distinct period in the wetland with HRT 2, 4, and 8 days, successively. Subsequently, a series of experiments was conducted to investigate the origin of the foams. Foams and the increase of COD concentration were found to be induced by the release of organic matter from the synthetic polypropylene fiber which was fed with piggery stormwater. Meanwhile, nitrogen removal was found to be enhanced during a period which overlapped the distinct foaming period signifying that foaming played two important functions in biological nitrogen removal. Foams which form rapidly and then burst easily could hold up and then release oxygen for nitrification. Foams which contain organic surfactants could serve as carbon sources for denitrification as well. Hence, nitrogen removal was enhanced during the foaming stage. After that, COD concentration decreased slowly to a level prior to the foaming stage, and nitrogen removal efficiency declined as well.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.768-772
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• 2010

In this study, the neuronal cell protective effects of methanol extract from cheonggukjang were evaluated. The proximate composition and total phenolics of the methanol extract were 40.95% crude protein, 22.49% crude fat, 15.99% nitrogen free extract, 7.91% moisture, 6.74% crude ash, 5.92% crude fiber, and 28.43 mg/g of total phenolics. Intracellular ROS accumulation resulting from $H_2O_2$ treatment of PC12 cells was significantly reduced when methanol extract was present in the media compared to PC12 cells treated with $H_2O_2$ only. In a cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromide (MTT), the methanol extract showed protective effects against $H_2O_2$-induced neurotoxicity, and lactate dehydrogenase (LDH) release into the medium was also inhibited. Furthermore, the inhibitory effect of the methanol extract against acetylcholinesterase was dose-dependent.

• Journal of the Korean Institute of Gas
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• v.19 no.4
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• pp.22-28
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• 2015

In order to keep the competitiveness of LPG fuel for transportation fuel, the difference in fuel consumption with gasoline and cost for an aftertreatment system should be reduced with continuous development of technology for LPG engine. In the present study, spray-guided type direct injection combustion system, whose configuration is composed of direct injector in the vicinity of spark plug, was employed to realize stable lean combustion. A certain level of nitrogen oxides($NO_x$) emits due to a locally rich mixture regions in the stratified mixture. With the application of EGR system for the reduction of $NO_x$, 15% of $NO_x$ reduction was achieved whereas fuel consumption and hydrocarbon emission increased. By the application of EGR, the combustion speed reduced especially appeared at initial flame development period and peak heat release rates and increasing rates for heat release rate decreased as EGR rate increased due to the dilution effect of intake air.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.31-41
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• 1986

The sufficient myoplasmic $Ca^{++}$ to react with the contractile proteins is necessary to induce contraction of a cardiac muscle. These $Ca^{++}$ for the production of muscle contraction are supplied from the three recognized $Ca^{++}$ sources; internal $Ca^{++}$ release via the sarcoplasmic reticulum(SR), $Ca^{++}$ influx through a gated Ca-channel in the membrane as a Isi, and $Ca^{++}$ transport by the mechanism of Na/ca exchange. However, it is still controversial which $Ca^{++}$ sources act as a main contributor for myoplasmic $Ca^{++}$, Therefore, this study was undertaken in order to examine the $Ca^{++}$ sources for the contraction of frog ventricle. There is evidence that the SR is sparse in frog ventricular fibers, and that T-tubules are absent. Isolated ventricular strips of frog, Rana nigromaculata, were used in this experiment. Isometric tension was recorded by force transducer, and membrane potentials of ventricular muscles were measured through the intracellular glass microelectrodes, which were filled with 3M KCI and had resistance of $30{\pm}50M{\Omega}$. All experiments were performed at room temperature in a tris·buffered Ringer solution which was aerated with 100% $O_2$. Isotonic high K, low Na solution was used to induce K-contracture, K-contracture appeared at the concentration of 20 to 30mM-KCI and was potentiated in parallel with the increase in KCI concentration. The contracture had two components: an initial rapid phasic and a subsequent slow tonic contractile responses. Membrane Potentials measured at normal Ringer solution(2.5mM KCI) was -90 to -100 mV, and decreased linearly as the KCI concentration increased; -55mV at 20mM.KCI, -45mV at 30 mM.KCI, -30 mY at 50 mM.KCI, and -12 mV at 100 mM.KCI. K-contracture was evoked firstly at the membrane potential of -45 mV. The contracture was potentiated by the increase of bathing extracellular $Ca^{++}$ concentration. However, in the absence of $Ca^{++}$ the contracture was almost not induced by 50 mM.KCI solution. Caffeine(20mM) in normal Ringer solution, which is known to release $Ca^{++}$ from SR without substantial effects on the $Ca^{++}$ fluxes across the surface membrane, did not affect membrane potential and also not initiate contracture, but the caffeine in 20 mM-KCI Ringer solution produced a contracture. Above results suggest that the main $Ca^{++}$ source for the K·contracture of frog ventricle is $Ca^{++}$ influx through the voltage-dependent Ca-channel, and that in the K-contracture at the concentration of 100 mM-KCI, the mechanism of Na/ca exchange also partly contributs, in addition to the $Ca^{++}$ influx.

• Nutrition Research and Practice
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• v.12 no.2
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• pp.93-100
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• 2018

BACKGROUND/OBJECTIVE: Oxidative stress plays a key role in neuronal cell damage, which is associated with neurodegenerative disease. The aim of present study was to investigate the neuroprotective effects of perilla oil (PO) and its active component, alpha-linolenic acid (ALA), against hydrogen peroxide $(H_2O_2)$-induced oxidative stress in SH-SY5Y neuronal cells. MATERIALS/METHODS: The SH-SY5Y human neuroblastoma cells exposed to $250{\mu}M$ $H_2O_2$ for 24 h were treated with different concentrations of PO (25, 125, 250 and $500{\mu}g/mL$) and its major fatty acid, ALA (1, 2.5, 5 and $25{\mu}g/mL$). We examined the effects of PO and ALA on $H_2O_2$-induced cell viability, lactate dehydrogenase (LDH) release, and nuclear condensation. Moreover, we determined whether PO and ALA regulated the apoptosis-related protein expressions, such as cleaved-poly ADP ribose polymerase (PARP), cleaved caspase-9 and -3, BCL-2 and BAX. RESULTS: Treatment of $H_2O_2$ resulted in decreased cell viability, increased LDH release, and increase in the nuclei condensation as indicated by Hoechst 33342 staining. However, PO and ALA treatment significantly attenuated the neuronal cell death, indicating that PO and ALA potently blocked the $H_2O_2$-induced neuronal apoptosis. Furthermore, cleaved-PARP, cleaved caspase-9 and -3 activations were significantly decreased in the presence of PO and ALA, and the $H_2O_2$-induced up-regulated BAX/BCL-2 ratio was blocked after treatment with PO and ALA. CONCLUSIONS: PO and its main fatty acid, ALA, exerted the protective activity from neuronal oxidative stress induced by $H_2O_2$. They regulated apoptotic pathway in neuronal cell death by alleviation of BAX/BCL-2 ratio, and down-regulation of cleaved-PARP and cleaved caspase-9 and -3. Although further studies are required to verify the protective mechanisms of PO and ALA from neuronal damage, PO and ALA are the promising agent against oxidative stress-induced apoptotic neuronal cell death.