• Korean Journal of Microbiology
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• v.47 no.2
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• pp.117-123
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• 2011

The purpose of this study was to evaluate and compare different elution and concentration methods for optimization of human rotavirus (HRV) detection method using real-time RT-PCR and cell culture techniques. The leafy vegetable samples (lettuce, Chinese cabbage) were artificially inoculated with HRV. Viruses were extracted from the vegetables by two different elution buffers, buffer A (100 mM Tris-HCl, 50 mM glycine, 3% beef extract, pH 9.5) and buffer B (250 mM Threonine, 300 mM NaCl, pH 9.5), and the extracted viruses were concentrated by filtration and PEG precipitation sequentially. To determine infectivity of the viruses, the viruses recovered from the samples were infected to the MA-104 cells, and integrated cell culture real-time RT-PCR was performed at 1, 48, 72, 96, 120, 144, 168 h post-infection (p.i.). The elution buffer A was more efficient in extracting the virus from the produce samples tested than the buffer B, 29.54% and 18.32% of recoveries, respectively. The sensitivity of real-time RT-PCR method was markedly improved when the virus was concentrated by the filtration method. When the viruses were eluted and concentrated by buffer A and filtration, respectively, the average recovery rate was approximately 51.89%. When the viruses recovered from samples were infected to MA-104 cell, infectious HRV was detected within 48 h p.i. by ICC/real-time RT-PCR, whereas cytopathic effects were not observed until 72 h p.i. The optimized detection method evaluated in this study could be useful for rapid and reliable detection of HRV in fresh produce products and applied for detection of other food-borne viruses.

• 한국벤처창업학회:학술대회논문집
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• 2006.04a
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• pp.45-75
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• 2006

How much influence does a business plan have on a corporate performance? Whilst previous studies and literatures all assert a strong correlation between the two, very few have actually conducted practical analyses to support that. This study takes an empirical approach in its analysis of Korea' s small and medium-sized enterprises (SME) with the view to finding an answer to the question. A business plan' s components, which have to date been suggested only in theory and in concept, have been selected through the study of literatures and preliminary examination. The selected components were then narrowed down into five factors of productivity, implementation, operational direction, product/service and customer accessibility by applying factor analysis. With which items to measure corporate performance is also an important question as results differ depending on which measurement items were used. For the purpose of this study, corporate performance was classified into effectiveness, adaptability and efficiency to measure how greatly each is influenced by the components of a business plan. Results show that effectiveness and adaptability have a positive (+) influence on corporate performance. The regression model seems to explain effectiveness particularly well. However, different directions of influences were showed in explain power of the research model were not high. And it can be interpreted that implementation of the plan is as important as the establishment of it. Thus a good corporate performance is to be had only under an excellent plan and following an excellent implementation. In most of the companies surveyed, business plans were established regularly led by the intense involvement of the CEO. Such plans were then used in internal operations, such as guiding operational direction and measuring corporate performance. Unlike general expectations, relatively few companies used them in financing from external sources such as banks or venture capitals. These findings are different from previous studies conducted in this field. Also, as market uncertainty was pointed out as the biggest obstacle to business planning. a manager must pay more attention to acquiring external information and knowledge so as to minimize it.

• Journal of Chest Surgery
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• v.30 no.3
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• pp.287-292
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• 1997

.Itrial fibrillation is one of the most common cardiac arrhythmias requiring treatment. About 60% of patients with mitral valvular disease have atrial fibrillation and one third of patients with atrial fibrillation may have the past history of thromboembolic events. Between April 1994 and June 1995, 20 patients with organic heart diseases combined with atrial fibrillation underwent open heart surgery including Cox-maze 111 procedure. There were 6 men and 14 women with an average age of 48 years (range, 31 to 66 years). Nineteen patients had valvular heart diseases and 1 ventricular septal defEct (VSD). Mean duration of atrial fibrillation was 36 months (:42 months) (range, 1 to 132 months). T e past medical history of thromboembolic events was positive in 7 patients (35%) and left atrial thrombus was detected in 9 patients (45%). The concomitant procedures were mitral valve replacement (MVR) and aortic valve replacement (AVR) in 5 patients, MVR in 4, MVd and tricuspid annuloplasty(TAP) in 4, mitral valvuloplasty(Mln) in 3, Mln and Tln in 1, MIW and coronary artery bypass surgery in 1, AVR in 1, and patch closure of VSD in 1. Mean aortic cross-clamping time was 175 minutes (range, 116 to 270 minutes). Atrial fibrillation recurred in 16 patients (80%) during the early postoperative period, but, recurrent atrial fibrillation was converted to regular rhythm at postoperative forty-first day in average. There was no early or late death in this series of 20 patients and postoperative complications were inappropriate tachycardia in 5 patients (25%), low cardiac output syndrome in 3 (15%), aggravated hemiplegic in 1, and acute renal failure in 1. Mean follow-up interval of patient was 16.5 months (range, 10.5 to 24 months) and all patients are currently in regular rhythm. Seventeen patients (85%) are in sinus rhythm and 3 (15%) in junctional rhythm. Right atrial contraction was detected in 95% of patients and left atrial contraction in 63% on postoperative transthoracic echocardiogram. The surgical treatment of atrial fibrillation concomitant with open heart surgery is warranted in the recent clinical setting of improved myocardial protection technique, considering the untoward side-effects of atrial fibrillation.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.74-82
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• 2002

The present study is aimed to investigate the effect of the safety hat on the balance of body temperature by observation of the physiological response under hot working environment. The experiment was carried out in a climate chamber of 3$0^{\circ}C$, 50%RH for 70 minutes. To compare the two kinds of safety hat, 5 healthy male subjects worn safety hat without hole (called 'without hole') or safety hat with hole (called 'with hole') according to a randomized cross-over design. The main results of this study are as fellows: Rectal temperature and heart rate were significantly lower level in 'with hole'than in 'without hole'. The mean skin temperature was significantly higher in 'without hole'than in 'with hole'. Blood pressure were significantly low in 'with hole'. Sweat rate which was measured by weight loss before and after experiment was higher in 'without hole'. In subjective ratings, subjects replied more hot, more uncomfortable and more wet, they felt more fatigue in condition of 'without hole'. Work ability which was measured by a grip strength dynamometer was higher in 'with hole'. Safety hat which can be used for safety of the brain in work place is meaningful device of behavioral thermoregulatory response under the hot working environment. The safety hat which is designed for proper ventilation and hygiene can maintain the homeostasis of body temperature by releasing body temperature efficiently.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.131-137
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• 2015

Commercial greenhouse plant factories are highly efficient for controlling external factors such as floods, drought, insects, air pollution etc. However, they require substantial startup & maintenance investments and experimental research to optimize production. These facilities are especially useful for urban farming where high efficiency in small spaces is required. In this study, we investigated whether light emitting diode (LED) lights with mixed dominant wavelengths (650 nm : 550 nm : 445 nm=8:1:1, 650 nm : 445 nm=6:4) can increase the growth rate and bio-active compound content of carrots in comparison to that of fluorescent light (FL). LED with mixed wavelength (650 nm : 550 nm : 445 nm=8:1:1) increased the total weight and root circumference of carrots compared to FL. However, ${\beta}$-carotene contents were not significant in LED (650 nm : 550 nm : 445 nm=8:1:1). However, LED (650 nm : 445 nm=6:4) increased the ${\beta}$-carotene (FL: 7.27, LED: 10.48 mg/g ${\beta}$-carotene dried weight). These results suggested that using LED light at the ideal wavelength, at the antithesis color of the plant, might enhance plant growth and bio-active compound contents.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.77-84
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• 2006

This study was conducted to find a system for screening organic resources with 16 species, 62 samples which were selected to randomizing point from city, province and industrial areas in the whole country. Content of organic matters were $65.3%{\sim}98.0%$ in all samples so that they were largely over than 60%, raw material regulation of compost. Concentrations of total nitrogen and total phosphorus were $0.7{\sim}4.8%\;and\;0.8{\sim}5.0$, they could look for effect of the nitrogen and phosphorus supply as a raw material of compost. In case of 8 elements concentrations of heavy metal, they were too high to use as raw materials of compost which were over to regulation limit in Cu, Cr, Ni, and As from fiber industry, Ni from food company and leather industry, and the others are adapt to limit levels. HEM contents fro the highest to $113mg\;kg^{-1}$ from liber industry and PAHs content were the highest to $3,462ug\;kg^{-1}$ from paper-mill manufacture. Distribution of PAHs concentiations were naphthalene>phenanthrene>pyrene>fluoroanthene>acenaphthene. $Microtox{(R)}\;EC_{50}$ values for bioassay were pharmaceutical company>paper-mill manufacture>industrial area sewage sludge>fiber industry>urban sewage sludge>metropolitan sewage sludge. HEM between Zn, Cu, and Ni was significant at the 99% and between Cd was significant at the 95%, Microtox between Hg and BEM significant at the 95%.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.260-267
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• 1998

This experiment used the enclosed bench-scale reactors of 242 liters was conducted to obtain basic data on temporal and spatial variations in temperature, oxygen and moisture content, which were important factors of biological activities, during composting of mixture of dairy manure and rice straw. The reactors with thermocouples, oxygen sensor and datalogger were aerated at four different rates of 0.09, 0.18, 0.90 and 1.79 l $min^{-1}kg$ dry $solids^{-1}$. The higher aeration rates were, the faster the rates of increase and decrease in composting temperature were in both of initial and turnover stage, and the smaller the temperature difference between exhaust air and composting materials. Composting temperature of initial stage increased suddenly in all aeration rates, then stationary phase of temperature in materials and exhaust air showed at $50{\sim}53^{\circ}C$ for 5 hours and at $45^{\circ}C$ between 5 and 15 hours, respectively. In initial stage the maximum temperature was decreased with increasing aeration rates but in the stage after turnover it was the opposite except for 1.79 l $min^{-1}kg^{-1}$. Time arrived at the maximum temperature of composting materials was later in low-aeration rates than high-aeration rates at both stages. Time maintained high-temperature more than $45^{\circ}C$ was rapidly decreased with increasing aeration rates. In initial stage of composting maintaining time of $65^{\circ}C$ or more was the longest in the treatments of 0.09 and 0.18 l $min^{-1}kg{-1}$, while those of $55{\sim}65^{\circ}C$ and $45{\sim}55^{\circ}C$ was in 0.90 and 1.79 l $min^{-1}kg{-1}$, respectively. The minimum oxygen content and the maximum oxygen consumption rate in exhaust air through composting materials showed the increased trends with increasing aeration rates. In initial stage the minimum oxygen content was ranged from 0.9% to 7.4% for 32 to 59.5 hours and the maximum oxygen consumption rate was $1.89{\sim}6.48$ $gh^{-1}kgVS^{-1}$. In the stage after turnover their levels were $2.1{\sim}19.9%$ and $1.76{\sim}3.49 %$g/h-㎏ VS, respectively, for 16 to 49.5 hours.

• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.41-49
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• 1993

The Study was conducted to develope the low temperature tolerant methane-producing bacteria(LTTB) and to increase the efficiency of anaerobic fermentation for the treatment of agricultural and livestock wastes at low temperature. The samples were collected from muddy soil, water logged sediment, organic layer and anaerobic sludge at three latitudes, $34.8{\sim}37.4\;^{\circ}N(Korea)$, $41.4\;^{\circ}N(USA)$ and $54.5{\sim}56.9\;^{\circ}N(Canada)$. They were used for determination of the methanogenesis rates for isolation and identification of the LTTB. The methanogenesis rate of smaples at low temperature were higher in the cellulose medium than methanol medium. The methanogenesis rate in the samples of subarctic region were $15{\sim}19$ moles/ml during 30 days at low temperature($8\;^{\circ}C$), whereas not detected in the samples of temperate region. The methanogenesis rate in the enrichment culture of subarctic samples were inhibited by the $40\;{\mu}g/ml$ of streptomycin + vancomycin or ampicillin + oleandomycin which were not effect to the methanogens. An inhabitation of high temperature tolerant methane producing bacteria was identified in the samples of temperate region, whereas that of the LTTB growing at $8{\sim}13^{\circ}C$ was identified in the subarctic region.

• Applied Microscopy
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• v.31 no.4
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• pp.355-365
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• 2001

This study was performed to investigate the distribution and differentiation on the immunoreacted cells of the ChAT (choline acetyltransferase) at the Meynert basal nucleus of the forebrains in the growth periods of rat, using the immunohistochemistric method. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT antibody reacted nerve cells in the Meynert basal nucleus of the rats were classified into six types. In the adult rats, the FD (frequency distributions) of round, oval and elongated cells were maximum. The FD of these types were shown to be progressively decreased during the postnatal development. In addition, the FD of elongated nerve cells in were observed in the adult rats respectively. This was thought to be the same phenomenon as those in the round and oval cells . The total mean volume of ChAT antibody reacted cell somata was lowest in the PND (postnatal days) 7 rats and was highest in the PND 21 rats. But, those were decreased to the adult. These results suggest that ChAT antibody reacted nerve cells grow up to PND 21 and then, differentiate into the various types by neurites outgrowing. On the electron micrography, the adult rat forebrain cells were obtained to be well developed ribosomes, polysomes , rough endoplasmic reticula and mitochondria. The immunreactivities were observed in ribosomes, polysomes, rough endoplasmic reticula and outer membrane of mitochondria. Golgi complexes were poorly developed and not showed jmmunreactivity. The ribosomes , polysomes and endoplasmic reticula are considered to be closely related to the inter cellular localization and biosynthesis of the ChAT but not Golgi complex. According to the results in the present study, it is considered that the ChAT-immunoreacted nerve cells in the Meynert basal nucleus of the rat forebrains are differentiated throughout the postnatal development with following processes of changes; 1) the cholinergic nerve cells develop postnatally 2) cell soma volumes gradually increase during the early postnatal days 3) and then, cells differentiate into the various types by projecting the neurites to the appropriate area after PND 21.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.455-468
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• 1998

For the objective interpretation of cerebral metabolic patterns in epilepsy patients, we developed computer-aided classifier using artificial neural network. We studied interictal brain FDG PET scans of 257 epilepsy patients who were diagnosed as normal(n=64), L TLE (n=112), or R TLE (n=81) by visual interpretation. Automatically segmented volume of interest (VOI) was used to reliably extract the features representing patterns of cerebral metabolism. All images were spatially normalized to MNI standard PET template and smoothed with 16mm FWHM Gaussian kernel using SPM96. Mean count in cerebral region was normalized. The VOls for 34 cerebral regions were previously defined on the standard template and 17 different counts of mirrored regions to hemispheric midline were extracted from spatially normalized images. A three-layer feed-forward error back-propagation neural network classifier with 7 input nodes and 3 output nodes was used. The network was trained to interpret metabolic patterns and produce identical diagnoses with those of expert viewers. The performance of the neural network was optimized by testing with 5~40 nodes in hidden layer. Randomly selected 40 images from each group were used to train the network and the remainders were used to test the learned network. The optimized neural network gave a maximum agreement rate of 80.3% with expert viewers. It used 20 hidden nodes and was trained for 1508 epochs. Also, neural network gave agreement rates of 75~80% with 10 or 30 nodes in hidden layer. We conclude that artificial neural network performed as well as human experts and could be potentially useful as clinical decision support tool for the localization of epileptogenic zones.