• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.22-33
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• 1991

The studies aimed to distinguish between initial (ionic or osmotic) effects of salinisation on growth and the longer-term consequences of excessive salt accumulation. Tall and dwarf varieties of rice were used to provide different growth rates. There was no significant effect upon the day-to-day pattern of growth, upon the ultimate length of leaves that were developing at the time of, or shortly after, salinisation with 50 mM NaCl. Leaves that developed after prolonged exposure of the plants to salinity were shorter. Addition of NaCl, KCl or mannitol to the root medium brought about a cessation of leaf elongation within one minute. Growth at a reduced rate restarted abruptly after a lag period that depended upon the external concentration. Elongation rate recovered to its original value within 24 hours after exposure to 50 mM NaCl, though not at higher concentrations. Addition of NaCl at concentrations up to 100 mM elicited no short-term effect upon photsynthetic gas exchange. No change in turgor pressure was detectable in the growing zone with the resolution of the miniature pressure probe used (about 70 kPa). It is concluded that the initial growth reduction in rice caused by salinisation is due to a limitation of water supply. A clear distinction is made between the initial effects of salt which are recoverable, and the long-term effects which result from the accumulation of salt within expanded leaves.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.101-111
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• 2017

The task of improving a fungal strain is highly time-consuming due to the requirement of a large number of flasks in order to obtain a library with enough diversity. In addition, fermentations (particularly those for fungal cells) are typically performed in high-volume (100-250 ml) shake-flasks. In this study, for large and rapid screening of itaconic acid (IA) high-yielding mutants of Aspergillus terreus, a miniaturized culture method was developed using 12-well and 24-well microtiter plates (MTPs, working volume = 1-2 ml). These miniaturized MTP fermentations were successful, only when highly filamentous forms were induced in the growth cultures. Under these conditions, loose-pelleted morphologies of optimum sizes (less than 0.5 mm in diameter) were casually induced in the MTP production cultures, which turned out to be the prerequisite for the active IA biosynthesis by the mutated strains in the miniaturized fermentations. Another crucial factor for successful MTP fermentation was to supply an optimal amount of dissolved oxygen into the fermentation broth through increasing the agitation speed (240 rpm) and reducing the working volume (1 ml) of each 24-well microtiter plate. Notably, almost identical fermentation physiologies resulted in the 250 ml shake-flasks, as well as in the 12-well and 24-well MTP cultures conducted under the respective optimum conditions, as expressed in terms of the distribution of IA productivity of each mutant. These results reveal that MTP cultures could be considered as viable alternatives for the labor-intensive shake-flask fermentations even for filamentous fungal cells, leading to the rapid development of IA high-yield mutant strains.

• Journal of Biosystems Engineering
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• v.37 no.3
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• pp.166-176
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• 2012

Purpose: This study was conducted to investigate the potential of interactance mode of NIR spectroscopy technology for the estimation of soluble solids content (SSC) and firmness of muskmelons. Methods: Melon samples were taken from local greenhouses in three different harvesting seasons (experiments 1, 2, and 3). The fruit attributes were measured at the 6 points on an equator of each sample where the spectral data were collected. The prediction models were developed using the original spectral data and the spectral data sets preprocessed by 20 methods. The performance of the models was compared. Results: In the prediction of SSC, the highest coefficient of determination ($R_{cv}{^2}$) values of the cross-validation was 0.755 (standard error of prediction, SEP=$0.89^{\circ}Brix$) with the preprocessing of normalization with range in experiment 1. The highest coefficient of determination in the robustness tests, $R_{rt}{^2}$=0.650 (SEP=$1.03^{\circ}Brix$), was found when the best model of experiment 3 was evaluated with the data set of experiment 2. The best $R_{cv}{^2}$ for the prediction of firmness was 0.715 (SEP=3.63 N) when no preprocessing was applied in experiment 1. The highest $R_{rt}{^2}$ was 0.404 (SEP=5.30 N) when the best model of experiment 3 was applied to the data set of experiment 1. Conclusions: From the test results, it can be concluded that the interactance mode of VIS/NIR spectroscopy technology has a great potential to measure SSC and firmness of thick-skinned muskmelons.

• Reproductive and Developmental Biology
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• v.36 no.3
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• pp.207-212
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• 2012

The shortage of human organs for transplantation has induced the research on the possibility of using animal as porcine. However, pig to human transplantation as known as xeno-transplantation has major problem as immunorejection. Recently, the solutions of pig to human xenotransplantation are commonly mentioned as having a genetically modification which include alpha 1, 3 galatosyl transferase knockout (GTKO) and immune-suppressing gene transgenic model. Unfortunately, the expression level of transgenic gene is very low activity. Therefore, development of gene overexpression system is the most urgent issue. Also, the tissue specific overexpression system is very important. Because most blood vessels are endothelial cells, establishment of the endothelial-specific promoter is attractive candidates for the introduction of suppressing immunorejection. In this study, we focus the ICAM2 promoter which has endothelial-specific regulatory region. To detect the regulatory region of ICAM2 promoter, we cloned 3.7 kb size mini-pig ICAM2 promoter. We conduct serial deletion of 5' flanking region of mini-pig ICAM2 promoter then selected promoter size as 1 kb, 1.5 kb, 2 kb, 2.5 kb, and 3 kb. To analyze promoter activity, luciferase assay system was conducted among these vectors and compare endothelial activity with epithelial cells. The reporter gene assay revealed that ICAM2 promoter has critical activity in endothelial cells (CPAE) and 1 kb size of ICAM2 promoter activity was significantly increased. Taken together, our studies suggest that mini-pig ICMA2 promoter is endothelial cell specific overexpression promoter and among above all size of promoters, 1 kb size promoter is optimal candidate to overcome the vascular immunorejection in pig to human xenotransplantation.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.3
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• pp.127-132
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• 2010

Reactive oxygen species (ROS), which include hydrogen peroxide ($H_2O_2$), the superoxide anion (${O_2}^-{\cdot}$), and the hydroxyl radical ($OH{\cdot}$), are generated as by-products of oxidative metabolism in cells. The cerebral cortex has been found to be particularly vulnerable to production of ROS associated with conditions such as ischemia-reperfusion, Parkinson's disease, and aging. To investigate the effect of ROS on inhibitory GABAergic synaptic transmission, we examined the electrophysiological mechanisms of the modulatory effect of $H_2O_2$ on GABAergic miniature inhibitory postsynaptic current (mIPSCs) in mechanically isolated rat cerebral cortical neurons retaining intact synaptic boutons. The membrane potential was voltage-clamped at -60 mV and mIPSCs were recorded and analyzed. Superfusion of 1-mM $H_2O_2$ gradually potentiated mIPSCs. This potentiating effect of $H_2O_2$ was blocked by the pretreatment with either 10,000-unit/mL catalase or $300-{\mu}M$ N-acetyl-cysteine. The potentiating effect of $H_2O_2$ was occluded by an adenylate cyclase activator, forskolin, and was blocked by a protein kinase A inhibitor, N -(2-[p-bromocinnamylamino] ethyl)-5-isoquinolinesulfonamide hydrochloride. This study indicates that oxidative stress may potentiate presynaptic GABA release through the mechanism of cAMP-dependent protein kinase A (PKA)-dependent pathways, which may result in the inhibition of the cerebral cortex neuronal activity.

• International Journal of Highway Engineering
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• v.16 no.3
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• pp.85-99
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• 2014

PURPOSES : This study has been performed with the objective to determine threshold zone luminance of adaptation luminance by target safety level in a vehicular traffic tunnel with design speed set at 100km/h. METHODS : The study made a miniature capable of portraying changes in luminance distribution within $2{\times}10^{\circ}$ conical field of view of the driver approaching to the tunnel for the test. Test conditions were set based on justifications for CIE 88-1990's threshold zone luminance used as a reference by domestic tunnel light standards (KS C 3703 : 2010). Luminance contrast of object background and object is 23%, object presentation duration is 0.5 seconds, and size of the object background is $7.3{\times}11.5m^2$ RESULTS : Threshold zone luminance was set within adaptation luminance of $100{\sim}3,000cd/m^2$. Adaptation luminance and threshold zone luminance based on 50%, 75% and 90% target safety level all showed a relatively high linear relationship. According to findings in the study, it is not appropriate to specify the relationship between adaptation luminance and threshold zone luminance as luminance ratio. Rather, direct utilization of the linear relationship gained from the study findings appears to be the better solution. CONCLUSIONS : Findings of this study may be used to determine operation of threshold zone luminance based on target safety level. However, a proper verification and validity of test results are required. Furthermore, a study to determine proper threshold zone luminance level considering target safety level reviewed in this study and various decision-making factors such as economic conditions in Korea and energy-related policies should be carried out in addition. Additional tests on adaptation luminance greater than $3,000cd/m^2$ will be performed, through which application scope of the test findings will be broadened.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.302-308
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• 2004

Sixty-six dogs diagnosed with cystolithiasis at animal clinics in the Busan area between April 2002, and April 2003, were reviewed. The chemical analysis of cystoliths from 66 dogs indicated that the predominant mineral component was struvite (45 dogs), calcium oxalate (14 dogs), or urate (6 dogs). Animals affected with struvite were grouped into four (s-1; struvite only, s-2; struvite mixed with lesser quantities of calcium oxalate or ammonium urate, s-3; nuclei and lamination, s-4; struvite nucleus surrounded by other minerals), with calcium oxalate into six(o-1; calcium oxalate monohydrate only, o-2; calcium oxalate dihydrate only, o-3; combination of calcium oxalate monohydrate and dihydrate, o-4; calcium oxalate nucleus surrounded by other minerals, o-5; 100% calcium oxalate monohydrate nucleus surrounded by 100% calcium oxalate dihydrate, o-6; mixed calcium oxalate monohydrate nucleus surrounded by mixed calcium oxalate dihydrate), and with urate into two(u-1; ammonium acid urate only, u-2; ammonium acid urate mixed with lesser quantities of other minerals). In this study, the numbers of 4 groups of struvite were (s-1; 10, s-2; 9, s-3; 21, s-4; 5), 6 groups of calcium oxalate were (o-1; 0, o-2; 1, o-3; 2, o-4; 3, o-5; 2, o-6; 6), and 2 groups of urate were (u-1; 6, u-2; 0). The data from each group was analyzed and compared. Shih Tzu(14 cases), Yorkshire terrier(10 cases), mixed-breed(10 cases) and Miniature schnauzer(7 cases) were more frequently affected than the other breeds. Females(40 cases) were affected more than males(26 cases). Twenty-nine dogs had cystoliths associated with a bacterial urinary tract infection, and uroliths tended to recur. We conclude eradication of urinary infection along with appropriate food (e.g. prescription diet) with client compliance should help in reducing the incidence or severity of the disease.

• Journal of Veterinary Clinics
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• v.25 no.4
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• pp.292-294
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• 2008

The purpose of this study was to evaluate the cause of lens luxation and to determine the frequency of vision loss, glaucoma, cataract, and corneal edema before and after intracapsular lens extraction (ICLE). The medical records of 8 dogs underwent ICLE for the correction of anterior lens luxation at the Veterinary Medical Teaching Hospital of Seoul National University from August 2005 to September 2007 were reviewed. The most frequently affected breed was Miniature Poodle (n = 3). The mean age was $10.8{\pm}2.1$ years. Preoperatively, 5 eyes (67.5%) with anterior luxation had secondary glaucoma, 7 eyes (87.5%) had vision loss, and all eyes (100.0%) had corneal edema. Four weeks after ICLE, 6 eyes (75.0%) had normal intraocular pressure (IOP), and 4 eyes (50.0%) regained vision. Corneal edema was reduced after ICLE in all eyes, but still remained in 4 eyes. It was considered that ICLE was beneficial in the management of anterior lens luxation, but the eyes without glaucoma before ICLE had more favorable prognosis than eyes with.

• Journal of Veterinary Clinics
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• v.31 no.4
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• pp.313-315
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• 2014

A 13-month old, intact female, miniature Schnauzer dog was presented with history of dermatitis, pruritus and pain of ear pinnae with delayed puberty. The basal serum growth hormone level was 0.01 ng/ml, which was much lower than the reference range (1.80-2.00 ng/ml). On the xylazine stimulation test, the dog was no responsive to administration of xylazine. The dog was diagnosed as isolated type pituitary dwarfism. Treatment was aimed to improve alopecia with oral melatonin. After initiation of treatment, alopecia of the ear pinnae has been improved.

• The Journal of the Korea Contents Association
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• v.8 no.4
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• pp.183-196
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• 2008

This research will mainly focus on security issues in a university campus and delve into the risk factors and its characteristics due to the extreme polarization growth, and ultimately conduct research on legislative issues regarding safety & security management. A university campus is a miniature of the society, concentrated with human resources, material resources and knowledge information resources. It is also a region in which various underlying risk factors threaten these resources. However, due to the insensibility of danger and carefree indolence, these risk factors have been ignoring, leaving university campus amidst a "dead zone." Currently, a systematic and synthetic measures not only for safety inside the laboratory but also for the new type of crimes such as cyber crimes and motiveless crime due to extreme polarization, stress, uneasiness about the future, increase of mental illnesses, and drug abuse are urgently required. Therefore, I would like to introduce a legislative program in a crisis management perspective that can prevent universities from danger and protect the resources which would ultimately create a new security system.