• Food Science of Animal Resources
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• v.40 no.6
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• pp.1014-1032
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• 2020

This work aimed to investigate the psychobiotic effects of six bacterial strains on the mind and behavior of male Wistar rats. The probiotic (PRO) group (n=7) were rats pre-treated with antibiotics for 7 days followed by 14-day probiotic administration, antibiotics (ANT) group (n=7) were rats treated with antibiotics for 21 days without probiotics. The control (CON) group (n=7) were rats that received sham treatment for 21 days. The six bacterial strains with probiotic properties were mostly isolated from Thai fermented foods; Pedicoccus pentosaceus WS11, Lactobacillus plantarum SK321, L. fermentum SK324, L. brevis TRBC 3003, Bifidobacterium adolescentis TBRC 7154 and Lactococcus lactis subsp. lactis TBRC 375. The probiotics were freeze-dried into powder (6×10⁹ CFU/5 g) and administered to the PRO group via oral gavage. Behavioral tests were performed. The PRO group displayed significantly reduced anxiety level and increased locomotor function using a marble burying test and open field test, respectively and significantly improved short-term memory performance using a novel object recognition test. Antibiotics significantly reduced microbial counts in rat feces in the ANT group by 100 fold compared to the PRO group. Probiotics significantly enhanced antioxidant enzymatic and non-enzymatic defenses in rat brains as assessed using catalase activity and ferric reducing antioxidant power assay, respectively. Probiotics also showed neuroprotective effects with less pyknotic cells and lower frequency of vacuolization in cerebral cortex. This multi-strain probiotic formulation from Thai fermented foods may offer a potential to develop psychobiotic-rich functional foods to modulate human mind and behaviors.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.232-239
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• 2001

Young Jong Grand Bridge is approach traffic road of New Inchon International Airport which covers hub airport function in northeast asia. The total span length of this bridge is $4,420{\cal}m$ and this main bridge type is, the first in the world, Double Deck Self Anchored Suspension Bridge, designed as double deck systems to be arranged by road and railroad. Approach bridges to be connected with main span also are composed double deck steel truss and steel box girder to consider a continuity with this span. Our company erected $1,375{\cal}m$(about 60,000tons) of double deck steel truss bridge type which is composed by 6 traffic lane on upper deck and 4 traffic lane and Double track railroad on lower deck. The original installation method of this bridge was planed to install about 75 meters bridge blocks to use floating crane, after temporary bent was constructed between permanent piers. But this method which had to construct many temporary bents in the sea had the matter that construction periods can become lengthen and construction cost can be risen. To overcome the uncertainty to ensure high qualify of bridge and economic project execution, our company developed new bridge erection method to assure both quality control and economic construction work. The new erection method which was developed by us was one that could transport and install long bridge block, $120{\cal}m$ unit at a time and that temporary bent was not required. We hope that this paper is used as technical data which will erect bridge in the western sea and others marine region.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.869-902
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• 1996

Flexion of a metal/ceramic fixed partial denture(EPD) frameworks under function can cause fracture of porcelain or deterioration of the cement seal. This study evaluated the flexion characteristics of three-unit mandibular FPD frameworks, repacing the second pre-molar under compressive load(200g, 400g). Testing was accompished with real-time holographic interferometry, using 6 porcelain fused-to metal frameworks. Tested alloys were non-precious alloy(Heracles, Holland), semi-precious alloy(Degudent U, Germany) and precious alloy(Degudent H, Germany). Changes of the fringe patterns according to the heat treatment(porcelain firing cycle), various loads(200g, 400g), occlusal forms(occlusal porcelain veneering, facial porcelain veneering), various alloys and post-soldering units were compared. Dental study model(Nissan dental products, Inc. D51DP-500A, Japan) and six 3-unit metal/ceramic fixed partial denture frameworks were used as experimental materials. 36 holograms were taken on fixed dental study model by using the 10mW He-Ne laser and real-time holographic interferometry. On the basis of this study, the following conclusions can be drawn : 1. In the frameworks for facial porcelain veneering, the semi-precious alloy framework was least deformed and precious alloy framework, non-precious alloy framework orderly before heat treatment, and the deformation was not shown great difference among three alloys after heat treatment and post-soldering. 2. In the frameworks for occlusal porcelain veneering, the precious alloy framework was greatest deformed and the deformation was not difference between semi-precious alloy framework and non-precious alloy framework before, after heat treatment, and the deformation was not shown great difference among three alloys after post soldering. 3. In the non-precious alloy frameworks for facial porcelain veneering and occlusal porcelain veneering, the deformation was greatly decreased after heat treatment and conversely increased after post-soldering. 4. In the semi-precious alloy framework for facial porcelain veneering, the deformation was not detectable after heat treatment and increased after post-solder. And in the frame-work for occlusal porcelain veneering, the deformation was slightly decreased after heat treatment and increased after post-soldering. 5. In the precious alloy framework for facial porcelain veneering, the deformation was greatly decreased after heat treatment and increased after post-soldering, And in the framework for occlusal porcelain veneering, the deformation was greatly decreased after heat treatment and decreased after post-soldering.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.53-59
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• 2009

The purpose of this study was to clarify the clinical efficiency of tungsten carbide/carbon coating on obtaining optimal preload of abutment screw compared with non-coated screw in external-hex implant system. In the present work, rotational value and the compressive force between abutment and fixture of abutment screws without coating and with coating tightened to 30Ncm were measured. Mean compressive force of coated screw was 504.6N. Then uncoated screw was tightened to clamping the abutment and the implant to 504.6N, and the tightening torque value and the rotational value was recorded. The following conclusions were drawn within the limitation of this study. Compressive force of coated screw was higher than that of uncoated screw after tightening at 30Ncm. The tightening torque that was nedeed to clamping the uncoated screw equal to coated screw tightened to 30Ncm was 55.6Ncm. In case of equal compressive force, there was no significant difference in rotation value between coated and uncoated screw.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10B
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• pp.939-945
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• 2008

Tn this paper we described the process and the results of an implementation of Internet terminal using G.729.1 wideband speech codec for next generation network. For this purpose firstly we chose a high performance RISC application processor having DSP features for speech codec processing and enhanced Multimedia Accelerator(eMMA) function for video codec. In the implementation of this terminal, we used G.729.1 codec recently standardized in ITU-T which is a new scalable speech and audio codec that extends 0.729 speech coding standard. To adopt G.729.1 codec to this terminal we transformed most of the fixed point C codes which require more complexity into assembly codes so as to minimize processing time in the processor. As a result of this work we reduced the execution time of the original C codes about 80% and operated in real time on the terminal. For video we used H.263/MPEG-4 codec which is supported by the eMMA with hardware in the processor. In the SIP call processing test connected to real network we obtained under looms end-to-end delay and 3.8 MOS value measured with PESQ instrument. Besides this terminal operated well with commercial terminals.

• Polymer(Korea)
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• v.25 no.2
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• pp.199-207
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• 2001

In the present study the cure behavior of diglycidyl ether of bisphenol-A(DGEBA) using an anhydride-based hardener in the presence of N,N-dimethyl benzyl amine (BDMA) or 1-cyanoethyl-2-ethyl-4-methyl imidazole (2E4MZ-CN) as an accelerator has been monitored and interpreted from the viewpoint of photophysical properties by means of fluorescence spectroscopy. To do this, 1,3-bis-(1-pyrene)propane (BPP) was well incorporated in the epoxy resin system by mechanical blending. The BPP probe, which is very sensitive to conformational change of the molecule influenced by the surrounding medium, successfully formed intramolecular excimer fluorescence. It is susceptible to the micro-viscosity or local viscosity and molecular mobility according to the epoxy cure. The cure behavior was explained with monomer fluorescence intensity ($I_{M}$ ), excimer fluorescence intensity ($I_{E}$ ) and $I_{M}$ /$I_{E}$ ratio as a function of cure time, cure temperature and accelerator. The present work agreed with the previous report on the cure behavior of an epoxy-anhydride system studied using DSC or torsion pendulum method. This study also suggests that the use of fluorescence technique may provide information on cure behavior of a thermosetting resin in a low temperature region, which has not been well interpreted by other analytical methods.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.363-377
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• 2002

The purpose of this study was to improve the problems of the voltaic cell described in the science textbooks of secondary schools. For this purpose, the contents of science textbooks which are related to the voltaic cell were analyzed and the problems which were not explained clearly by theorems were tried to be explained by experiments, and lastly sug-gestions were made toward the improvements regarding the voltaic cell in the science textbooks. The findings are that there are problems on the ways of ensuring whether the voltaic cell operates properly as a chemical battery, on the explanation of why the hydrogen bubbles form at the zinc electrode, on the cell potential, on the unification of the electrode terminology used, and on the mention of the current. Solutions to the problems except the cell potential were suggested. According to the experiment, the theoretical potential was calculated by considering the potentials of redox reactions at the two electrodes of the cell and by taking into account the characteristics of the electrodes such as the work function, ionization energy, stan-dard reduction potential, and electronegativity.The cell potential of the voltaic cell is explained by several factors. In the improved version of the textbook's introduction section to the voltaic cell, it is necessary to describe the voltaic cell his-torically.For the conceptual section, it should be explained in terms of the Daniel cell.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.29-42
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• 1998

$Mg^{2+}$ is one of the most abundant divalent cations in mammalian body(0.2~1.0mM) and the important physiological roles are : first, the cofactor of many enzyme activities, second, the regulator of glycolysis and DNA synthesis, third, the important role of bioenergetics by regulating of phosphorylation, fourth, the influence of cardiac metabolism and function. In this work we have investigated the regulation of the $Mg^{2+}$ induced by ${\alpha}_1-adrenoceptor$ stimulation in perfused guinea pig hearts and isolated myocytes. The $Mg^{2+}$ content of the perfusate or the supernatant was measured by atomic absorbance spectrophotometry. The elimination of $Mg^{2+}$ in the medium increased the force of contraction of right ventricular papillary muscles, and the left ventricular pressure. Phenylephrine also enhanced the force of contraction in the presence of $Mg^{2+}-free$ medium. ${\alpha}_1-Agonists$ such as phenylephrine and methoxamine were found to induce $Mg^{2+}$ efflux in both perfused hearts and myocytes. These effects were blocked by prazosin, an ${\alpha}_1-adrenoceptor$ antagonist. The $Mg^{2+}$ influx could also be induced by phenylephrine and R59022, a diacylglycerol kinase inhibitor. In the presence of protein kinase C(PKC) inhibitors, phenylephrine produced an increase in $Mg^{2+}$ efflux from perfused hearts. Furthermore, $Mg^{2+}$ efflux by phenylephrine was amplified by phorbol 12-myristate 13-acetate(PMA). This enhancement of $Mg^{2+}$ efflux by PMA was blocked by prazosin in perfused hearts. By contrast, the $Mg^{2+}$ influx could be induced by verapamil, nifedipine, ryanodine in perfused hearts, but not in myocytes. $W^7$, a $Ca^{2+}$/calmodulin antagonist, completely blocked the phenylephrine-induced $Mg^{2+}$ efflux in perfused hearts. In conclusion, $Mg^{2+}$ is responsible for the cardiac activity associated with ${\alpha}_1-adrenoceptor$ stimulation. The mobilization of $Mg^{2+}$ is decreased or increased by ${\alpha}_1-adrenoceptor$ stimulation in guinea pig hearts. These responses may be related specifically to the respective pathways of signal transduction. A decrease in $Mg^{2+}$ efflux by ${\alpha}_1-adrenoceptor$ stimulation in hearts can be through PKC dependent and intracellular $Ca^{2+}$ levels.

• Membrane Journal
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• v.26 no.3
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• pp.197-204
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• 2016

The objective of this work was to investigate the performance of pervaporation process for recovery of ester compounds from model aqueous solutions and how the fluxes of esters and water were affected by changes in feed concentration and temperature. The flux of ethyl acetate (EA), propyl acetate (PA), ethyl propionate (EP), butyl acetate (BA), and ethyl butyrate (EB) increased with an increase in feed concentration from 0.15 wt% to 0.60 wt%, and increased with temperature change from $30^{\circ}C$ to $50^{\circ}C$. The flux of esters (EA, PA, EP, BA, and EB) was in order of (EA) < (PA, EP) < (BA, EB). This result meant that the flux strongly depended on affinity between esters and membrane surface; EA is the least hydrophobic because it has one hydrophobic function group ($-CH_2-$), (PA, EP) have two ($-CH_2-$), and (BA, EB) are the most hydrophobic because these have three ($-CH_2-$). As well as such an influence of hydrophobicity of ester molecules on ester flux, the influence of hydrophobicity of membrane surface on ester flux needs further investigation. With increase in temperature, water flux of aqueous EA, PA, EP, BA, and EB solution increased. However, water flux of aqueous ester solutions did not change appreciably with increase in concentration. This experimental results may be used as fundamental data for pervaporation (PV) to improve the aroma recovery process as an alternative to thermal evaporation and distillation processes.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.299-326
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• 1998

1. Comparison of demand and supply A. Assumption of estimation of demand and supply we will briefly assumptions used for presumption once more before comparing the result of estimation of demand and supply examined previously 1) supply - The average applying rate for state. examination of graduate: ${\alpha}$=1.03109 - The ratio of successful applicants of state examinations: ${\beta}$=0.97091 - Mortality classified by age : presumed data of the Bureau of statistics - Emigrating rate: 0 % - Time of retire: unconsidered - An army doctor number: unconsidered and regard number of employed oriental medicine doctor. - Standard of 1995 : The number of survival oriental medicine doctor is 8195. the number of employed oriental medicine doctor is 7419. 2) demand - derivated demand method Daily the average amount of medical treatment: according to medical insurance federation data. there is 16 or 6 non allowance patient, we consider amount of medical treatment as 22 persons in practical because 21.94 persons (founded practical examination) are converted to allowance in comming demand. Daily the proper amount of medical treatment: 7 hours form -35 persons 5 hours 30 minutes form -28 persons. Yearly medical treatment days: 229 days. 255 days. 269 days . Increasing rate of visiting hospital days: -1996 year. 1997 year. 1998 year- . Rate of applying insurance: yearly average 71.51% (among the investigated patient) B. Comparison of total sum result 1) supply (provision) Table Ⅳ-1 below shows the estimation of the oriental medicine doctor in the future.