• Journal of Chest Surgery
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• v.31 no.10
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• pp.919-923
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• 1998

Background: Calcific degeneration is unavoidable in either homo- or heterografts implanted in the human body. We have developed a calcification-resistant cardiovascular tissue patch using a novel technique of anticalcification. Materials and methods: Fresh bovine pericardium was harvested at the slaughter house and transfered to the laboratory in Hank's solution. After trimming and fixing the pericardium, it was embedded in 4$^{\circ}C$ 0.65% glutaraldehyde for a week and then washed by phosphate-buffered saline(PBS) of pH 7.4. This prepared pericardium was then stored in 2.5% sulphonated polyethyleneoxide(PEO-SO3) solution for 2 days at room temperature and reversed by 4$^{\circ}C$ NaBH4 solution for 16 hours. To evaluate the calcification-resistance of surface modified bovine pericardium with PEO-SO3, either glutaraldehyde- treated(GA group, n=4) or PEO-SO3-treated pericardial patch(PEO-SO3 group, n=4) was implanted into adult mongrel dog to reconstruct the main pulmonary artery and the descending aorta using a partial clamp technique. After 1 month follow-up, the implanted patches were retrieved to evaluate the pathologic findings and the content of calcium and phosphorous. Results: The PEO-SO3 group showed substantially less retraction and significantly less calcium deposition than the GA group in both aortic(7.10$\pm$1.05 vs. 13.81$\pm$2.33 mg/g of dried tissue) and pulmonary positions(1.55$\pm$0.29 vs. 6.72$\pm$0.70 mg/g)(p<0.01). Phosphorous contents were also less in the PEO-SO3 group than the GA group significantly, 8.11$\pm$1.07 mg/g vs. 19.33$\pm$4.31 mg/g in the aortic and 2.58$\pm$0.40 vs. 12.60$\pm$3.40 mg/g in thepulmonary position(p<0.01). Conclusions: These findings suggest that PEO-SO3 modified bovine pericardium is highly calcification-resistant but further study is needed to evaluate the long-term biological safety and compatibility of the prosthesis.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.57-65
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• 2010

Physical activity of the people has decreased due to a sedentary lifestyle according to developing the economy throughout the world. It is thought to increase the risk of chronic diseases, including obesity, diabetes, etc. People are interested in walking, which is an easy activity to engage in as an antidote to chronic diseases. The aim of this study is to increase the diminishing physical activity of modem society by inducing walking as part of everyday life through building a walking-based activity-friendly city where people can live merrily, safely and pleasantly. For this purpose, this study conducted a satisfaction survey to dwellers of Jinhae on the physical pedestrian environments which affect determining walking participation and intentions of people, and also provided a valid model to evaluate the effects of the physical environmental factors on walking satisfaction using factor analysis and multiple linear regression analysis. The results are summarized as follows. The 18 variables of the physical pedestrian environments were selected based on pre-literature reviews. The results of the satisfaction surveys showed that the satisfaction of crossing aids in segments was highest, while the building feature was the lowest. Factor analysis was run through a two-step process. The first analysis was conducted to examine the adequacy of this factor analysis on the selected 18 variables. As a result, two variables were removed and the remaining 16 variables were extracted to the four factors by second analysis. Each factor was named function of path, effect of traffic, amenity and safety based on the each factor's commonality. Each factor score of the extracted four factors was set as the independent variable, while the overall walking satisfaction was set as the dependent variable. Then, the multiple linear regression analysis was conducted and showed that all four factors had a positive influence on the overall satisfaction of walking, especially the 'function of path' and 'amenity' factors, followed by 'effect of traffic' and 'safety'. The results of this research will be used as foundational data for creating a walking-based activity-friendly city.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.334-343
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• 1997

This study was performed to elucidate the effects of dietary calcium-salt, estrogen-treatment, and estrogen/calcium treatment on bone metabolism. Ovariectomized rats were used as an animal model. Female Sprague-Dawley rats with a body weight of $250{\sim}280g$ underwent ovariectomy or sham-operation. The ovariectomized rats were divided into 9 different experimental groups including saline-treated group, estrogen-treated group, high calcium salt-treated group, and estrogen/calcium treated groups, and fed the experimental diet for 6 weeks. The mineral content, weight, length, strength and density in femur and scapula of the animals were determined. The results of the experiment are as follows: there were no difference in weight of wet bone, density, length, strength and content of ash in right femur between ovariectomized rat and sham-operation. When the weight of bones was expressed as bone gram per body weight, it was significantly lower in ovariectomized rat than sham-operation. Estrogen and estrogen/calcium in ovariectomized rats resulted in increased weight of wet bone. Estrogen with its gradual reduction in ovariectomized rats showed the lowest values in strength, content of ash, content of calcium and content of phosphorus among the groups. There were no differences in weight of wet hone, density, content of ash, content of calcium and content of phosphorus in right scapula between ovariectomized rat and sham-operation. In addition skeletal composition was not changed by ovariectomy. Estrogen and estrogen/calcium in ovariectomized rats resulted in decreased skeletal composition however, estrogen with its gradual reduction did not caused the skeletal composition change. Moreover, the gradual reduction of estrogen had a preventive effect on bone loss when the treatment was combined with calcium intensification.

• The Korean Journal of Nuclear Medicine
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• v.30 no.3
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• pp.315-324
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• 1996

The purpose of this study was to compare the specific binding ratio method with model-based methods in estimating the transporter parameter $k_3/k_4$ in normal controls and Parkinson's patients with [I-123]IPT SPECT and to evaluate the usefulness of [I-123]IPT SPECT. $6.5{\pm}1.1$ mCi ($239.0{\pm}40.3$ MBq) of [$^{123}I$]IPT was intravenouly injected as a bolus into six normal controls(age:$45{\pm}13$) and seventeen patients(age:$55{\pm}8$) with Pakinson's disease(PD). The transporter parameter $k_3/k_4$ was derived using the Ichise's graphical method($R_v$) and Lassen's area ratio method($R_A$) for the dynamic IPT SPECT data without blood samples. Then, the relationships between the transporter parameter $R-v,\;R_A$ and the ratio of (BG-OCC)/OCC at 115 minutes were evaluated by linear regression analysis. $R_vs$ by Ichise's graphical method for NC and PD were $2.08{\pm}0.29$ and $0.78{\pm}0.31$, respectively. $R_As$ by Lassen's area ratio method for NC and PD were $1.48{\pm}0.16$ and $0.65{\pm}0.24$, respectively. The correlation coefficients between (BG-OCC)/OCC and $R_v$, (BG-OCC)/OCC and $R_A$, and $R_v$ and $R_A$ were 0.93, 0.90, 0.99 and their corresponding slopes were 0.54, 0.34, and 0.65, respectively. The $R_v$ and $R_A$ of NC were significantly higher than the ones of PD. That is, the $k_3/k_4$ of NC was clearly separated from the one of PD. $k_3/k_4$ showed a good correlation with the ratio of (BG-OCC)/OCC. The results indicate that the noninvasive simplified quantitative methods may be useful to measure the transporter parameter $k_3/k_4$ and the specific binding ratio method can be used for quantitative studies of dopamine transporter with [I-123]IPT SPECT in humans brains.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.1
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• pp.25-38
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• 2003

This study was conducted to establish the microbiological quality standards applying the HACCP system on sushi items of Japanese restaurant in Korea. The study evaluated hygienic conditions of kitchen and workers, pH time-temperature relationship, and microbial assessments during whole process of sushi making in 2001. Overall hygienic conditions were normal for both kitchen and for workers by 3 point scale, but hygienic controls against the cross-contamination were still needed. Each process of sushi making was performed under the risk of microbial contamination, since pH value of most of ingredients was over pH 4.6 and also production time(3.5~6 hrs) were long enough to cause problems. Microorganisms were high enough to cause foodborne illness ranged 8.0$\times$10$^2$~3.3$\times$10$^{6}$ CFU/g of TPC and 1.0$\times$10$^1$~1.6$\times$10$^3$CFU/g of coliforms, although TPC, coliforms and Staphylcoccus aureus were within the standard limits (TPC 10$^2$~10$^{6}$ CFU/g, coliforms 10$^3$CFU/g). However, Salmonella and Vibrio parahaemolyticus were not detected. High populations TPC and coliforms were also found in the cooks' hands and cooking utensils(TPC 10$^2$~10$^{6}$ CFU/100cm$^2$and Coliforms 10$^1$~10$^3$CFU/100cm$^2$). Based on the CCP decision tree analysis, the CCPs were the holding steps far six sushi production line except the tuna and the thawing step for tuna sushi. In conclusion, overall state of sushi production was fairly good but much improvement was still needed.

• Korean Journal of Cognitive Science
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• v.28 no.4
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• pp.193-221
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• 2017

Grouping episodes into semantically related categories is necessary for better mnemonic structure. However, the effect of grouping on memory of subordinate details was not clearly understood. In an fMRI study, we tested whether attending superordinate during semantic association disrupts or enhances subordinate episodic details. In each cycle of the experiment, five cue words were presented sequentially with two related detail words placed underneath for each cue. Participants were asked whether they could imagine a category that includes the previously shown cue words in each cycle, and their confidence on retrieval was rated. Participants were asked to perform cued recall tests on presented detail words after the session. Behavioral data showed that reaction times for categorization tasks decreased and confidence levels increased in the third trial of each cycle, thus this trial was considered to be an important insight where a semantic category was believed to be successfully established. Critically, the accuracy of recalling detail words presented immediately prior to third trials was lower than those of followed trials, indicating that subordinate details were disrupted during categorization. General linear model analysis of the trial immediately prior to the completion of categorization, specifically the second trial, revealed significant activation in the temporal gyrus and inferior frontal gyrus, areas of semantic memory networks. Representative Similarity Analysis revealed that the activation patterns of the third trials were more consistent than those of the second trials in the temporal gyrus, inferior frontal gyrus, and hippocampus. Our research demonstrates that semantic grouping can cause memories of subordinate details to fade, suggesting that semantic retrieval during categorization affects the quality of related episodic memory.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.98-106
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• 2011

Establishing conservation programs to protect and maintain populations of endangered species are not only a global trend, but also a pursuit endorsed by the Korean Environmental Conservation Act. This study evaluates the feasibility of alternative habitat patches for the endangered butterfly Parnassius bremeri. A portion of habitat of P. bremeri is expected to be fragmented and damaged due to the scheduled construction of the Sangju-Yongduk Highway. A trans fer of the habitat patches of P. bremeri is also scheduled. In order to select an alternative habitat patch, the Mark-Release-Recapture (MRR) method was used to simulate a patch transfer model. The connectedness between habitat are as and the survival of local populations were evaluated for each candidate habitat. It was found that metapopulations with patch distances of <250m showed a 50% connectedness and survival rate in local populations. P. bremeri were expected to migrate at an average distance of 300m. In addition, P. bremeri formed a metapopulation that exhibited intimate patch dynamics that promoted persistence among these patches. Possible candidate habitats including those recommended by local governing bodies were evaluated along with habitats that may counter problems arising from the damage done to the original habitat and habitats that may have a compensatory value equal to that of the original habitat. Based on these criteria, Ansa-myeon township office was selected due to its high scores. This scoring was based on a consideration of a wide range of variables that mark a successful transfer of habitat. These include the amount of funding available, the governing bodies of the possible alternative habitat, and the Expected collaborative effort of local citizens. This decision was collaborated on by incorporating the expertise of various fields of study including biology, ecology, biogeography, ecological engineering, landscape architecture, and social sciences. Therefore, it is suggested that in order to evaluate an alternative habitat for organisms, many social issues as well as ecological issues must be considered.

• Journal of radiological science and technology
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• v.34 no.3
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• pp.239-244
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• 2011

In this study, we evaluated diffusion weighted imaging (DWI) to investigate whether the DWI parameters can predict characteristic parameters on pathologic specimens of tumor or not. CFPAC-1 was injected subcutaneously on the back flank of athymic nude mice (n=13) then two tumors were initiated on each mouse (2${\times}$13=26 tumors). The mice were sacrificed to make specimen immediately after initial MR imaging then were compared with the MR image. A dedicated high-field (7T) small-animal MR scanner was used for image acquisitions. A T1 and T2 weighted axial image using RARE technique was acquired to measure the T2 values and tumor size. DWI MR was performed for calculating ADC values. To evaluate tumor cellularity and determine the levels of MVD, tumor cells were excised and processed for H-E staining and immunostaining using CD31. T2 values and ADC values were computed and analyzed for each half of the tumors and compared to the correlated specimens slide. Median ADC within each half of mass was compared to the cellularity and MVD in the correlated area of pathologic slide. The mean of ADC value is $0.7327{\times}10^{-3}$ $mm^2/s$ and standard deviation is $0.1075{\times}10^{-3}$ $mm^2/s$. There is a linear relationship between ADC value and tumor necrosis (R2=0.697, p< 0.001). DW image parameters including the ADC values can be utilized as surrogate markers to assess intratumoral neoangiogenesis and change of the internal structure of tumor cells.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.4
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• pp.149-165
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• 2016

The objectives of this study is to assess the influence of individual characteristics and economic environment on the entrepreneurship such as entrepreneurial Intention and behavior based on the theory of Planned behaviors. This study used a country-level merged data set composed of GEM(Global Entrepreneurship Monitor) data and the OECD Statistics data. And this used the fixed effect model to analyze the panel data of 31 OECD countries during the period from 2005 to 2014. Our findings show that subjective norm has a significantly positive effect on entrepreneurial intention. In individual characteristics, the perceived opportunities has a significantly positive effect on early-stage entrepreneurial activity(TEA) and improvement-driven opportunity entrepreneurial activity. We identify the differences of between necessity-driven and improvement-driven opportunity entrepreneurial activity. For example, the effect on necessity-driven entrepreneurial activity is significantly negative. We also find the differences of between necessity-driven and improvement-driven opportunity entrepreneurial activity in economic environment variables. While real GDP growth as a demand variable has a significantly positive effect on necessity-driven entrepreneurial activity, unemployment rate as a supply variable has a significantly negative effect on early-stage entrepreneurial activity(TEA) and improvement-driven opportunity entrepreneurial activity. And GDP per capita as a supply variable has a significantly positive effect on early-stage entrepreneurial activity(TEA) and improvement-driven opportunity entrepreneurial activity. But the effect on necessity-driven entrepreneurial activity is significantly negative. We provide an interpretation of these empirical findings, emphasizing the importance of considering individual characteristics and economic environment simultaneously in promoting entrepreneurship.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.5
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• pp.127-139
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• 2017

In recent 10 years the attention to social entrepreneurship has raised increasing among scholars, public sector, and community development. However less research has been conducted on how social entrepreneurship intention create a social enterprise and what factors can be affected to the social entrepreneurial intentions. This paper aims at contributing to identify the antecedents of entrepreneurial behavior and intentions. Especially, we have had a strong interests in compassion factors which haven't been used as important variables to encourage for people to do social entrepreneurial activities. Also, we try to find the moral obligation and perceived social support as antecedents of social entrepreneurial intentions. Finding show that compassion and moral obligation affect to the social entrepreneurial intention. Especially this study identify the external factor of society with the variable, perceived social support. Once individuals recognize that the infrastructure and societal positive mood on social entrepreneurship is friendly to social entrepreneurship, people have a tendency to try to do some social entrepreneurial activities. Only few empirical studies exist in this research domain. A study of more than 271 Korean college students has studied which personal traits predict certain characteristics of social entrepreneurs (such as having social vision or looking for social innovational opportunities). In addition to those antecedents, students experience is the critical factor that enabled continued expansion of the social entrepreneurial activities. The results of this research show how we can nurture social entrepreneurs and how we can develop the social environment to promote social entrepreneurship.