• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.6
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• pp.29-43
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• 2019

This paper empirically analyzed the relationship between the characteristics of venture business founders and management performance, setting the management strategy as a parameter to provide a suggestion for the survival and development of venture companies that play an important role in the national economy and job creation. Previous studies in Korea have analyzed the relationship between the characteristics of business founders, management strategies and management performance in a single dimension. This paper, however, explained the business performance of a company from a multi-dimensional perspective while setting the characteristics of business founders as independent variables and setting the business strategy of the enterprise as a parameter. The first result of the analysis shows that the characteristics of venture business founders have a positive effect on business performance. In particular, among the characteristics of venture business founders, a progressive spirit has had the greatest impact on business performance. On the other hand, the influence of risk sensitivity was very weak. Second, the characteristics of venture business founders were found to have a positive effect on business strategy. In particular, innovation was an important variable that affected the technological innovation differentiation strategy, and a progressive spirit was the most influential factor in the marketing differentiation strategy. Third, management strategies of venture firms were found to have a positive effect on business performance. In particular, the technology innovation differentiation strategy has a greater impact on business performance than the marketing differentiation strategy. Fourth, it was revealed that management strategy partially has a mediated effect on the relationship between the characteristics of venture business founders and management performance. In other words, it was found that the characteristics of the founders have a direct impact on business performance but if it is linked to management strategy it has an indirect effect on business performance. The results of this study show that business performance improves when venture business founders' personal characteristics and the firms' management strategy are combined.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.3
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• pp.220-226
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• 2017

Dopamine (DA) and serotonin (5-Hydroxytryptamine, 5-HT) are neurotransmitters and hormones that exist in small amounts but have important role in the body. Serum and 24-hour urine are used as specimens, and are usually examined by HPLC-MS. In this study, we tried to detect DA and 5-HT by competitive ELISA using antigen-antibody (Ab) reaction. After immobilizing $5{\mu}g/mL$ BSA conjugate on a 96-well surface, hormone and primary Ab, which are respectively diluted to different concentrations, were treated. Then, HRP-conjugated secondary Ab and TMB were added to measure absorbance. The regression equation and $R^2$ value were calculated based on absorbance, and sensitivity of Ab to hormone as well as the correlation between hormone concentration and absorbance were determined. In DA ELISA, $R^2$, the correlation between the concentration of hormone and absorbance, was the highest by 0.91 when anti-dopamine Ab was diluted 6,000 times and 7,000 times. In 5-HT ELISA, $R^2$ was bigger than 0.90 in every concentration except 3,000 times and 6,000 times. Both DA and 5-HT were not effectively detected at low concentrations (less than $1.0{\times}10^{-7}M$); and because reference value of serum DA is lower than this, HPLC-MS was required to detect serum DA. However, competitive ELISA may be effective in detecting 24-hour urine DA, serum, and 24-hour 5-HT. Further studies are needed to detect hormones more accurately at lower concentrations.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.9-13
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• 2016

Purpose PET-CT examinations using $^{18}F-FDG$ to treat urinary system cancer are limited in terms of anatomical structure and excretion route of $^{18}F-FDG$. But one of the ongoing examinations utilizing $^{11}C-Acetate$ can compensate for such defects. We would like to introduce a clinical application of $^{11}C-Acetate$ PET-CT in urinary cancer patients. Materials and Methods We conducted a clinical survey of 22 patients diagnosed with urinary cancer at our hospital, 10 prostate cancer patients, 10 renal cell carcinoma patients, and 2 bladder cancer patients. All patients were performed $^{18}F-FDG$ PET-CT examinations, $^{11}C-Acetate$ examinations were performed after two weeks on average. The equipment used to D-710 PET-CT in GE Company and we performed PET-CT procedures 15 minutes after injecting $^{11}C-Acetate$, and a medical doctor from the department of nuclear medicine appraised and compared images between $^{18}F-FDG$ and $^{11}C-Acetate$. Results According to our survey, prostate cancer patients generally had lower uptake of $^{18}F-FDG$ than other cancer patients did. In 2 out of 10 prostate cancer patients, metastasized cancer showed greater uptake in $^{11}C-Acetate$ than $^{18}F-FDG$. In renal cell carcinoma cases, 8 out of 10 patients displayed evidently greater uptake in $^{11}C-Acetate$ than $^{18}F-FDG$. We excluded bladder cancer cases in this study because uptake of $^{18}F-FDG$ in the bladder was too hot, the number of patients was insufficient, and the cases did not meet criteria such as the use of diuretics. Conclusion It is too premature to draw solid conclusions from the survey, since it involved only a small number of participants. However, there are a number of studies conducted abroad that prove the effectiveness of the $^{11}C-Acetate$ PET-CT examinations in treating urinary system cancer, and this study is still ongoing at our hospital. If the tests were to be conducted on a larger number of participants, this study could lead to numerous other potential research topics, such as the correlation between Prostatic specific antigen (PSA) values and $^{11}C-Acetate$ PET-CT, Gleason sum values from biopsy before surgery, Specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV) between $^{18}F-FDG$ PET-CT examinations and $^{11}C-Acetate$ PET-CT examinations in other urinary system cancers.

• Pediatric Infection and Vaccine
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• v.14 no.2
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• pp.162-170
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• 2007

Purpose : While cases of vancomycin-resistant enterococci (VRE) have increasingly been reported worldwide since it was first reported in the late 1980s, there have been few systemic studies on the pediatric population. The purpose of this study is to contribute to the planning of VRE prevention by investigating the prevalence, risk factors and transmission of VRE infection. Methods : We studied 230 patients under age 15 years who were isolated VRE between January 2001 and December 2006 retrospectively. The patients were classified into the intensive care unit (ICU) and the non-ICU groups. We reviewed the procedures before VRE detection as well as antibiotic sensitivity of detected organisms. Results : The number of VRE-isolation cases was higher in the ICU group than the non-ICU group. Instances of VRE-isolation were also more prevalent in patients who underwent operations or active procedures while taking 3rd-generation cephalosporins or glycopeptides. Almost all antibiotics except tetracycline were resistant to VRE. The proportion of 3rd-generation cephalosporin use was higher than those of any other antibiotics before VRE detection. Additionally, the use of 3rd-generation cephalosporins has increased annually, but that of glycopeptides had decreased in 2006. Also, the rates of VRE isolation have been increasing since 1998. Conclusion : VRE infection is increasing in pediatric population. Strict adherence to appropriate infection control guidelines for the prevention of VRE transmission in hospitals, and tracking of VRE colonization through active surveillance in high risk units are recommended.

• Investigative Magnetic Resonance Imaging
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• v.1 no.1
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• pp.94-102
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• 1997

Purpose: There have been some efforts to diagnose intracranial aneurysm through a non-invasive method using MRA, although the process may be difficult when the lesion is less than 3mm. The present study prospectively compares the results of high resolution, fast speed slice interpolation MRA and DSA thereby examing the potentiality of primary non-invasive screening test. Materials and Methods: A total of 26 cerebral aneurysm lesions from 14 patients with subarachnoid hemorrhage from ruptured aneurysm (RA) and 5 patients with unruptured aneurysm(UA). In all subjects, MRA was taken to confirm the vessel of origin, definition of aneurysm neck and the relationship of the aneurysm to nearby small vessels, and the results were compared with the results of DSA. The images were obtained with 1.5T superconductive machine (Vision, Siemens, Erlangen, Germany) on 4 slabs of MRA using slice interpolation. The settings include TR/TE/FA=30/6.4/25, matrix $160{\times}512$, FOV $150{\times}200$, 7minutes 42 seconds of scan time, effective thickness of 0.7 mm and an entire thickness of 102. 2mm. The images included structures from foramen magnum to A3 portion of anterior cerebral artery. MIP was used for the image analysis, and multiplanar reconstruction (MPR) technique was used in cases of intracranial aneurysm. Results: A total of 26 intracranial aneurysm lesions from 19 patients with 2 patients having 3 lesion, 3 patients having 2 lesions and the rest of 14 patients having 1 lesion each were examined. Among those, 14 were RA and 12 were UA. Eight lesions were less than 2mm in size, 9 lesions were 3-5mm, 7 were 6-9mm and 2 were larger than IOmm. On initial exams, 25 out of 26 aneurysm lesions were detected in either MRA or DSA showing 96% sensitivity. Specificity cannot be estimated since there was no true negative of false positive findings. When MRA and MPR were used concurrently for the confirmation of size and shape, the results were equivalent to those of DSA, while in the confirmation of aneurysm neck and parent vessels, the concurrent use of MRA and MPR was far superior to the sole use of either MRA or DSA. Conclusion: High resolution MRA using slice interpolation technique showed equal results as those of DSA for the detection of intracranial aneurysm, and may be used as a primary non-invasive screening test in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.156-164
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• 2015

High temperature stress would affect rice production in the future as heat wave is expected to occur frequently under climate change conditions. The objective of this study was to obtain rudimentary information to assess the impact of heat stress on rice yield and its yield component in Korea. Two rice cultivars "Hwaseongbyeo" (Japonica) and "Dasanbyeo" (Tongil-type) were grown at different nitrogen fertilization levels in two seasons. These cultivars were grown in 1/5000a Wagner pot placed within four plastic houses where temperature was controlled at ambient, ambient$+1.5^{\circ}C$, ambient$+3^{\circ}C$ and ambient$+5^{\circ}C$ throughout the rice growing season in Suwon ($37^{\circ}16^{\prime}N$, $128^{\circ}59^{\prime}E$), Korea. The degree of temperature change affected grain yield whereas the level of nitrogen had little impact on grain yield. The number of panicle per pot and spikelet per panicle were not significantly different among temperature treatments in both cultivars tested. In contrast, 1000-grain weight and ripened grain ratio were decreased significantly under the treatments raising the air temperature to the level of $5.0^{\circ}C$ and $1.5^{\circ}C$ above the ambient air temperature in Dasanbyeo and Hwaseongbyeo, respectively. Reduction of 1000-grain weight and ripened grain ratio under the temperature treatments of $3.0^{\circ}C$ and $5.0^{\circ}C$ above the ambient air temperature resulted in significantly less grain yield for Dasanbyeo and Hwaseongbyeo, respectively. The greater sensitivity of grain yield to temperature increase in Dasanbyeo was attributable to the sharp decrease of 1000-grain weight and ripened grain ratio with the temperature rise above $23^{\circ}C$ during ripening period. On the other hand, Hwaseongbyeo had little variation of them in the temperature range of $23-27^{\circ}C$. These results suggested that grain yield would decrease under future climate conditions due to grain weight decreased by shorter grain filling period as well as the ripened grain ratio reduced by spikelet sterility and early abortion of rice kernel development. Thus, it would be essential to use cultivars tolerant to heat stress for climate change adaptation, which merits further studies for developing varieties that have traits to avoid spikelet sterility and early abortion of rice kernel, e.g., early morning flowering, under heat wave.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.716-722
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• 2005

Purpose : A full view of the spectrum of all bacterial diseases in healthy children is essential to the establishment of public health priorities. Accurate information on the relative importance of the various pathogens in terms of the age of the affected patients, the site of infection and the case fatality rate are valuable to the clinician in choosing antimicrobial treatments. Methods : Fifty-nine episodes of bacteremia were analysed. Data were collected at Ilsan Paik Hospital from January 2000 to December 2003. Analysis of each collected episode included isolating pathogen from blood culture, diagnosis, hospital course, isolating pathogens from other tissue sites, and studying results of antimicrobial sensitivity tests. Results : Fifty-nine cases of community-acquired bacteremia were reviewed. The most common pathogen was Staphylococcus aureus(11 cases, 18.6 percent), followed by Salmonella(10 cases, 16.9 percent), E. coli(7 cases, 11.9 percent), Streptococcus pneumoniae(five cases, 8.5 percent), Streptococcus viridans(5 cases 8.5 percent). The most common diagnosis was bacteremia without an indentified focus(61 percent), followed by meningitis(12 percent), bacteremia with enteritis(10.2 percent) and bacteremia with urinary tract infection(8.5 percent). Salmonella was still an important causative agent of bacteremia. The relative importance of Haemophilus influenza and Streptococcus pneumoniae was lower than in other studies. The most common organism responsible for bacteremia without an identified focus was Staphylococcus aureus. The case-fatality was 3.4 percent for all cases of bacteremia. Conclusion : We reviewed the etiology of community-acquired bacteremia. These data may be useful in the establishment of public health priorities and serve as a reference for selection of antibiotics in the empirical therapy of suspected invasive bacterial infection.

• Analytical Science and Technology
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• v.11 no.5
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• pp.347-352
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• 1998

A study was carried out on the elelctrochemical characteristics of chemically modified electrodes (CMEs) by cyclic voltammetry. Fabrication of CMEs was made by coating with mixed valence (mv) inorganic-metal polymeric films on the glassy carbon electrode surface by potential cycling. Anodic oxidation behavior of methanol and L-ascorbic acid was studied by using CMEs working electrode. Deposition of films such as mv ruthenium oxo/ruthenium cyanide film (mv Ru-O/CN-Ru), mv ruthenium oxo/ferrocyanide film (mv Ru-O/$Fe(CN)_6$), and mv ruthenium oxo/ruthenium cyanide/Rhodium film (mv Ru-O/CN-Ru/Rh) was obtained to coat by scan rate of 50 mV/sec within the specified potential range (-0.5V ~ +1.2V). Film thickness was controlled by the repeat of the potential cycling. Anodic oxidation behavior of methanol was as follow. Calibration graph by using mv Ru-O/CN-Ru film showed linearly from 10 mM to 80 mM MeOH with slope factor of $-7.552{\mu}A/cm^2$. Although slope factor by using mv Ru-O/$Fe(CN)_6$ film was $-5.13{\mu}A/cm^2$, yet linear range of calibration graph could be extended from 10 mM to 100 mM MeOH. Anodic oxidation behavior of L-ascorbic acid was studied by mv Ru-O/CN-Ru film on the glassy carbon electrode and the glassy carbon electrode with Rh film, Glassy carbon electrode modified with Ru polymeric film was showed better sensitivity than the Rh-glassy carbon modified electrode (mv Ru-O/CN-Ru/Rh). Calibration graph was linear from 0.1 mM to 5 mM L-ascorbic acid by using glassy carbon electrode modified with Ru polymeric film. Solpe factor and relative coefficient are $-84.78{\mu}A/mM$ and 0.998, respectively.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.7 no.2
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• pp.77-83
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• 2014

Purpose: The purpose of current study was to evaluate the validity of the existing radiological classifications as a diagnostic modality for predicting characteristics of calcific deposition in calcific tendinitis of the shoulder joint. For that purpose, we determined the inter-observer reliability for evaluating diagnostic precisions of the classification and also evaluated diagnostic accuracy of predicting the toothpaste type calcific deposition. Materials and Methods: We performed retrospective study with total 26 patients surgically treated with calcific tendinitis of the shoulder joint from March 2010 to October 2013. Two independent observers reviewed preoperative radiographs of shoulder joints, and classified the characteristics of calcific depositions according to the criteria of Gartner, DePalma and Patte. Cohen's kappa were calculated for each classifications to evaluate inter-observer reliability. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were determined for type of calcific depositions with Gartner type III, DePalma type I, and Patte type II for predicting toothpaste type calcific deposition. Results: The values of Cohen's kappa were the highest in the classification of Patte, 0.62, and the values for the classifications of DePalma and Gartner were 0.56 and 0.36, respectively. The sensitivities for predicting toothpaste type calcific deposition in Gartner Type III, DePalma type I and Patte type II were 83.3%, 91.7%, and 58.3%, respectively. Specificities were 85.7% 50.0% and 64%, positive likelihood ratios were 5.833, 1.833 and 1.633, negative likelihood ratios were 0.194, 0.167 and 0.648, and diagnostic odds ratios were 30.00, 11.00 and 2.52, respectively. Conclusion: There were no radiologic classifications of calcific tendinitis which has both high precision and accuracy. Further studies with other diagnostic modalities such as ultrasonography are needed for predicting characteristics of calcific deposition in calcific tendinitis of the shoulder joint.

• Clinical and Experimental Pediatrics
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• v.48 no.10
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• pp.1126-1131
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• 2005

Purpose : Bronchial hyperresponsiveness(BHR) is considered a hallmark of asthma. Increased levels of eosinophil cationic protein(ECP) have been identified in serum of asthma patients. Several studies have examined the relationship between serum ECP and bronchial responsiveness, expressed as methacholine $PC_{20}$ in asthmatic patients, with conflicting results. The aims of this study were to examine the relationship between serum ECP and ${\Delta}FVC$, another index of bronchial responsiveness, which reflects increased maximal airway response. Methods : Six to 8-year-old children with asthma(n=109) underwent methacholine bronchoprovocation testing. The $PC_{20}$ dose of methacholine and ${\Delta}FVC$ were calculated for each individual from the methacholine dose response curves. Serum ECP levels and blood total eosinophil counts were also measured. Results : Serum ECP correlated with ${\Delta}FVC$(r=0.217, P=0.023), as well as $PC_{20}$(r=-0.208, P=0.030). However, blood eosinophil counts failed to show any correlations with ${\Delta}FVC$(r=0.085, P=0.378) or $PC_{20}$(r=-0.148, P=0.125). ${\Delta}FVC$ did not correlate with $PC_{20}$(r=-0.079, P=0.417). Conclusion : Blood eosinophil activation is associated with both components of BHR including increased sensitivity and increased maximal response in 6-8 year old children with asthma.