• The Korean Journal of Physiology
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• v.29 no.2
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• pp.279-289
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• 1995

This study was designed 1) to develop a hypertensive animal model in which the blood pressures (BPs) of symmetric regions (right and left upper extremities) are significantly different and 2) to test the effect of BP per se on the contractility and endothelium-dependent relaxation of vascular smooth muscle. Rabbits were anesthetized with sodium pentobarbital and ventilated with room air via animal respirator. The transverse aorta was exposed through the left second intercostal space and the lumen of the aorta was narrowed partially by ligation using 3-0 silk and a probe at a point between the origins of the brachiocephalic trunk and the left subclavian artery. Four to eight weeks postoperatively, BPs were measured in the carotid artery as the high BP area (proximal to coactation site) and in the femoral artery as the low BP area (distal to coarctation site). In the animal model, pressure-overload hypertension was developed and the BP of the right subclavian artery was higher than that of the left subclavian artery. The concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II were measured. The right and left subclavian arteries and their branches were used for isometric tension recording in organ baths and their responsiveness to phenylephrine, serotonin, acetylcholine, and sodium nitroprusside were examined. The BPs of carotid and femoral artery in control animals were $116{\pm} 12/75{\pm}9\;mmHg (mean ${\pm}SEM$) and $130{\pm}16/68{\pm}9\;mmHg$ respectively, while those of carotid and femoral artery in the hypetensive animals were $172{\pm}6/111{\pm}10\;mmHg$ and 136{\pm} 4/100 {\pm}9\;mmHg$ respectively. There were no significant differences in the concentrations of circulating epinephrine, norepinephrine, angiotensin I, and angiotensin II between controls and the animal models. No significant differences were found in the vascular sensitivities to phenylephrine and serotonin between the high pressure-exposed vessels and the low pressure-exposed vessels. However, the endothelium-dependent relaxation to acetylcholine and nitroprusside-induced relaxation showed significant differences between the high pressure-exposed and the low pressure-exposed subclavian arteries. From the above results, we suggest that the contractility of vascular smooth muscle is unchanged by the elevated pressure per se. However, the endothelium-dependent relaxation to acetylcholine and the nitroprusside-induced relaxation are attenuated by pressure.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.807-815
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• 2018

This study was investigated the effect of dietary probiotic mixture on blood biomarkers, immune responses, caecal microorganism and productivity in broiler chickens under heat stress (HS). A total of 400 broiler chick males (Ross 308) were divided into four groups of 100 heads each, group C (control, room temperature $25^{\circ}C$), HS (heat stress $33^{\circ}C$) and HSP (HS plus probiotic mixture 500, 750 mg/kg of diet), respectively. Broiler body weight gain, feed intake, feed conversion ratio and immune organ weight increased in the HSP group compared to the HS group. The concentrations of blood IgG and lymphocyte were increased in the HSP group compared to the HS group, and the heterophil:lymphocyte (H:L) ratio, corticosterone concentration and mortality were low. Lactobacillus in the cecum increased in the HSP group compared to the HS group, but was lower in Escherichiacoli (E. coli), coliform bacteria and aerobic bacteria. These results indicate that feeding probitic mixture including three strains such as B. subtilis, S. galilaeus and Sphingobacteriaceae to broiler exposed to heat stress can improve production with lowering mortality by improving immune response and microbial balance.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.787-796
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• 2018

This study was conducted to investigate the effects of probiotic mixture on fecal ammonia, caecal microorganism, immune response, egg quality and production in layer under heat stress (HS).A total of four hundred 50 week olds Hy-Line Brown layers were randomly divided into four groups of 100 heads each: C (control, room temperature $25^{\circ}C$), HS (heat stress $33^{\circ}C$), PM (HS plus probiotic mixture 500, 750 mg/kg of diets). Egg production, egg quality, spleen weight, blood IgG and lymphocyte concentrations were increased in the PM group compared to the HS group, while mortality, the heterophil:lymphocyte (H:L) ratio, and corticosterone levelswere significantly decreased. Lactobacillus was increased in the PM group compared to the HS group, but E. coli, coliform bacteria and aerobic bacteria were significantly reduced. Fecal ammonia production was significantly increased in the HS group compared to the PM group. In conclusion, the results of this study that these mixed probiotics can reduce the heat damage of the summer laying hens and can be an effective nutritional strategy to reduce odor generation from feces, and to improve egg quality and laying production through immune response and caecal microbial balance.

• Resources Recycling
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• v.9 no.1
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• pp.52-62
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• 2000

In order to maximize the recycling of converter slag to the more valuable fields, such as high quality aggregates for construction, cement industry and flux for ion making. It will be very important to control the compositions and properties of converter slag to suit the purpose of utilizastion. In this study, converter slag (STELCO, CANADA) was mixed with 5%~30% $SiO_2$and 7% carbon, and then reduced at $1650^{\circ}C$. After the reduction was completed, the reformed slags were cooled to room temperature in the furnace. All of the slags were then characterized using SEM-EDX, XRD and chemical analysis. Also the compressive strengths and densities of the reformed slags were measured to compare with natural aggregates. XRD analysis shows that th phases of reformed slags are changed from bredigite+merwinite mixed phases of 10% $SiO_2$added reduction to akermanite phases of 20% and 30% $SiO_2$ added reduction. But the SEM-EDX analysis revealed that the phase distribution of the reformed slags was changed very sensitively and complicately depends on the change of slag compositions. And also the properties of reformed slags are changed very much depend on the phase distribution. About one third of Cadmium and on fifth of Vanadium are remained in reduction reformed converter slag. Another heavy metal elements such as cobalt, zinc, lead are removed up to more than 90-95% of original slag. The compressive strength and density of 25% $SiO_2$ added and reformed slag is very near to natural granite. This is superior more than 10% to Thyssen's $SiO_2$ added and oxidized converter slag aggregates.

• Food Science and Preservation
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• v.16 no.3
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• pp.371-375
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• 2009

Electron spin resonance (ESR) spectroscopy was used to detect radiation-induced signals from irradiated spices and ESR parameters were analyzed to define specific signals. Four powdered spices (red pepper, garlic, onion, and black pepper) were irradiated with 0, 1, 5, or 10 kGy at room temperature using a [60Co] gamma-ray irradiator prior to ESR analysis. Radiation-induced triplet signals, including those from the cellulose radical, which are center signals ($g_2=2.00673$) within the range of 3.0455 mT, were observed in all irradiated spice samples. The parameters g-value, center field, and signal range of hyperfine triplet ESR signals were constant in all irradiated samples, being specific for cellulose radicals and thereby distinguishing these signals from those of nonirradiated control samples. High positive correlation coefficients ($R^2=0.8452-0.9854$) were obtained between irradiation doses and corresponding ESR signal intensities. Thus, reliable detection of irradiated dried spices by measurement of ESR cellulose signals was confirmed by parameter analysis for the cellulose radical.

• Korean Journal of Medicinal Crop Science
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• v.25 no.1
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• pp.37-44
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• 2017

Background: The light emitting plasma (LEP) has recently attracted attention as a novel artificial light source for plant growth and functional component enhancement. We investigated the effects of LEP on whitening and antioxidant activities of the plant parts of perilla. Methods and Results: Previously germianted seeds of perilla were cultivated under different light conditions (fluoresce lamp, LED red, blue, white, green, and LEP) in a culture room for 2 months. Parts of perilla were harvested and extracted in 70% EtOH. The extracts were used to detect total phenolic contents, total flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power and tyrosinase inhibition activity as indicators of biological activity. Biological activity was highest in seedlings grown under LEP. The total phenolic content was highest in the stems and the total flavonoid content was highest in the roots of perilla exposed to LEP. The DPPH and ABTS radical activity in all the parts of perilla exposed to LEP were higher by approximately three-fold compared to that in the control (fluoresce lamp). The reducing power values of perilla significantly increased after treatment with LEP. In addition, all the extract of perilla plants exposed to LEP promoted the tyrosinase inhibitory activity. These results suggest that LEP can be an important artificial light source for enhancement of biological activity. Conclusions: LEP could promote whitening and antioxidant activity of perilla.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.57-58
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• 2006

The effects of lowering ECAP temperature during ECAP process and Post-ECAP annealing on microstructure, texture and mechanical properties of the AZ31 alloys have been investigated in the present study. The as-extruded materials were ECAP processed to 2 passes at 553K prior to subsequent pressing up to 6 passes at 523K or 493K. When this method of lowering ECAP temperature during ECAP was used, the rods could be successfully deformed up to 6 passes without any surface cracking. Grain refinement during ECAP process at 553K might have helped the material to endure further straining at lower deformation temperatures probably by increasing the strain accommodation effect by grain boundary sliding, causing stress relaxation. Texture modification during ECAP has a great influence on the strength of Mg alloys because HCP metals have limited number of slip systems. As slip is most prone to take place on basal planes in Mg at room temperature, the rotation of high fraction of basal planes to the directions favorable for slip as in ECAP decreases the yield stress appreciably. The strength of AZ31 Mg alloys increases with decrease of grain size if the texture is constant though ECAP deformation history is different. A standard positive strength dependence on the grain size for Mg alloys with the similar texture (Fig. 1) supports that the softening of ECAPed Mg alloys (a negative slope) typically observed despite the significant grain refinement is due to the texture modification where the rotation of basal planes occurs towards the orientation for easier slip. It could be predicted that if the original fiber texture is restored after ECAP treatment yielding marked grain refinement, yield stress as high as 500 MPa will be obtained at the grain size of ${\sim}1{\mu}m$. Differential speed rolling (DSR) with a high speed ratio between the upper and lower rolls was applied to alter the microstructure and texture of the AZ31 sheets. Significant grain refinement took place during the rolling owing to introduction of large shear deformation. Grain size as small as $1.4{\mu}m$ could be obtained at 423K after DSR. There was a good correlation between the (0002) pole intensity and tensile elongation. This result indicates that tensile ductility improvement in the asymmetrically rolled AZ31 Mg alloys is closely related to the weakening of basal texture during DSR. Further basal texture weakening occurred during annealing after DSR. According to Hall-Petch relation shown in Fig. 1, the strength of the asymmetrically rolled AZ31 is lower than that of the symmetrically rolled one when compared at the same grain size. This result was attributed to weakening of fiber texture during DSR. The DSRed AZ31, however, shows higher strength than the ECAPed AZ31 where texture has been completely replaced by a new texture associated with high Schmid factors.

• Journal of Hydrogen and New Energy
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• v.11 no.3
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• pp.119-125
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• 2000

To improve the photochemical energy conversion efficiency and the stability of CdS particulate film electrode which is used to produce hydrogen from the aqueous $H_2S$ solution photoelectrochemically, surface treatment of this film was carried out using $TiCl_4$ solution. CdS particles for preparation of the films were synthesized by precipitation reaction of $Cd({NO_3})_2{\cdot}9H_2O$ and $Na_2S{\cdot}4H_2O$. Then, the CdS sol was hydrothermally treated for 12hr in an autoclave with the variation of treatment temperature to control the crystalline phase of particles. CdS film electrode was thus prepared by annealing at $400^{\circ}C$ for 12hr of the wet-film cast at room temperature, and subsequently surface treated with $TiCl_4$ solution. The electrodes were characterized using XRD, SEM, and the photocurrent meter. The photocurrents of Cds film electrodes prepared with surface treatment were up to two times higher than the electrodes without surface treatment, indicating about $4.0mA/cm^2$. Hydrogen production rate in a continuous flow system using photoelectrochemical or photochemical cells prepared with surface treatment also increased in proportion to the increase of photocurrents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.94-101
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• 2011

Squid (Todarodes pacificus) is processed as dried or seasoned-dried products and its catch gradually increased from 270,298 M/T in 2005 to 367,940 M/T in 2008 in Korea. Squid processing by-product (viscera) was usually discarded as a waste resulting in environmental problem. In order to utilize squid viscera for more value-added products, a natural squid seasoning was developed by fermenting with Aspergillus oryzae koji. Squid viscera at 5, 10 and 15% salt concentrations with fixed levels of 5% koji and 30% water was fermented at room temperature. The quality properties of squid fermented products such as amino-N, TMA, VBN, total viable cell count, pH and total acidity were determined at different fermentation periods. The contents of amino-N, TMA, and VBN of squid seasoning at 5% salt concentration fermented for 14 days were the highest. Based on amino-N content, squid viscera at 5% koji fermented for 14 days was selected for further assays: the content of moisture, crude protein, crude lipid, crude ash, and carbohydrate were 5.98, 35.19, 33.08, 11.30, and 14.45%, respectively. The content of glutamate, alanine, leusine and lysine were 7.06, 12.34, 9.90 and 10.22%, respectively. The $IC_{50}$ values of DPPH scavenging and $\beta$-glucuronidase inhibitory activity were 12.89 and 12.58 mg/mL, respectively. A natural squid seasoning was manufactured by mixing fermented squid viscera and an ingredient. Based on the results of sensory evaluation, the fermented squid viscera seasoning was almost equal to other natural complex seasonings such as anchovy, cow meat, and fisheries seasoning.

• The Journal of the Korean dental association
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• v.50 no.12
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• pp.763-770
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• 2012

The purposes of this work were to assess the cognition of the registered nurse(RN) on oral and maxillofacial emergency treatment and to compare cognition of the RN with that of the 119 emergency medical technician(EMT). 450 RNs who were working at each of secondary hospitals in Jeju province had responded to the questionnaire. Independent sample t-test and chi-square test were used to assess the state of RN on dental emergency treatment and to compare RN with EMT. The question 'education time on dentistry in formal education' that marked '0 hour' and '1-3 hours' were 73.3% and 20.0%, respectively. The question 'refresher training class on dentistry' that marked '0 hour' and '1-3 hours' were 92.9% and 6.7%, aggregately 99.6%. The results showed low score in the question 'reduction of temporo-mandibular joint(TMJ)'($1.67{\pm}0.857$), 'fixation of dislocated TMJ'($1.70{\pm}0.853$) and 'post-avulsed tooth treatment'($1.78{\pm}0.774$) by 5-point Likert scale. Likewise, the scores were $2.02{\pm}0.806$ in the question 'treatment of maxillofacial trauma', $2.76{\pm}1.061$ in the question 'emergent care of avulsed tooth', $2.70{\pm}1.095$ in the question 'treatment time of avulsed tooth' and $2.79{\pm}1.056$ in the question 'mouth guard', respectively. Compared to EMT, results of RN showed a statistically lower figure(p<0.05) in all items compared except the question 'medicine control', and the question 'doctor care in emergency room' was borderline(p=0.069). From this study, it is necessary for RN and student of nursing science to be educated on the oral and maxillofacial emergency treatment for the initial management of injuries. Authors suggest further co-study and nation-wide research with nursing care.