• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.5
• /
• pp.682-688
• /
• 2011

The purpose of this study was to measure the blood glucose level and glycemic index (GI) in response to persimmon (Diospyros kaki Thunb) syrup extracted from persimmon and extract of persimmon by-products. Major component analyses of persimmon syrup I (PSI, 95:5 mixture of purified persimmon syrup and non-purified persimmon syrup) and persimmon syrup II (PSII, 50:50 mixture ratio of purified persimmon syrup and non-purified persimmon syrup) were $0.3{\pm}0.1$ and $0.6{\pm}0.2$ mg/g for total polyphenolic compounds and $70.6{\pm}0.6$ and $66.6{\pm}1.6%$ for total carbohydrates, respectively. Blood glucose responses of PSI and PSII were determined using both normal ICR mice and streptozotocin (STZ)-induced diabetic male Sprague-Dawley (SD) rats. Further, oral glucose tolerance test (OGTT) was performed on diabetic rats to assess the effects of the experimental diets. Blood glucose response and OGTT showed that blood glucose levels were significantly lower in mice and diabetic rats fed PSI and PSII compared to those fed diets of sugar, maple syrup, or honey. The GIs of healthy volunteers in response to PSI and PSII were calculated to be 51.9 and 35.7, respectively. On the contrary, the GIs of healthy volunteers fed diets including sugar, maple syrup, or honey were 52.6, 20.0, and 93.0, respectively. These results suggest that persimmon syrup can be used for both the treatment of diabetics and healthy people due to its beneficial effects on blood glucose level.

• Journal of Oral Medicine and Pain
• /
• v.32 no.3
• /
• pp.283-292
• /
• 2007

In several treatment modalities for snoring and obstructive sleep apnea (OSA), oral appliances mainly including mandibular advancement appliance (MAA) and tongue retaining device (TRD) are recognized as a non-invasive, reversible alternative with favorable results. Tongue bulb is a major component of TRD which prevents the tongue from approaching the posterior wall of the pharynx and can be combined with MAA. Determination of tongue bulb size for the patient is important for therapeutic effect, but frequently needs time-consuming work. For effective fabrication and standardization of tongue bulbs, this study aimed to categorize tongue bulb size for healthy young men and to examine its relation with maximum retention force and with physical parameters including tongue-related variables. 36 non-snoring, asymptomatic young men with normal occlusion were voluntarily participated in this study (mean age: $24.47{\pm}2.58$ years). Experimental procedures consisted of prefabrication of tongue bulb set (20 types with a width of 27-36mm and thickness of 8 and 10 mm), determination of tongue bulb size and the maximum retention force for each subject, and measurement of physical parameters including body mass index (BMI), neck circumference and width, thickness and length of tongue. This study showed that there was significant difference of retention force among the bulb size-related groups both in upright and supine position (p<0.05) and that retention force increased with bulb size. Correlation of tongue bulb size with physical parameters was not clearly verified and there was no significant difference in retention force between upright and supine positions. Based on our results, it can be suggested that retention force relates with tongue bulb size, ultimately with tongue volume. A further study needs to be performed in the patients with snoring and OSA.

• Journal of Periodontal and Implant Science
• /
• v.30 no.4
• /
• pp.851-870
• /
• 2000

The major goals of periodontal therapy is the functional regeneration of periodontal supporting structures already destructed by periodontal disease as well as the reduction of signs and symptoms of progressive periodontal disease. There have been many efforts to develop materials and therapeutic methods to promote periodontal wound healing. There have been increasing interest on the chitosan made by chitin. Chitin is second only to cellulose as the most abundant natural biopolymer. It is a structural component of the exoskeleton of invertebrates(e.g., shrimp, crabs, lobsters), of the cell wall of fungi, and of the cuticle of insects. Chitosan is a derivative of chitin made by deacetylation of side chains. Many experiments using chitosan in various animal models have proven its beneficial effects. The aim of this study is to evaluate the osteogenesis of chitosan on the calvarial critical size defect in Sprague Dawley rats. An 8 mm surgical defect was produced with a trephine bur in the area of the midsagittal suture. The rats were divided into two groups: Untreated control group versus experimental group with 50mg of soluble chitosan gel. The animals were sacrificed at 2, 4 and 8 weeks after surgical procedure. The specimens were examined by histologic, histomorphometric and radiodensitometric analyses. The results are as follows: 1. The length of newly formed bone in the defects was $102.91{\pm}25.46{\mu}m$, $219.46{\pm}97.81{\mu}m$ at the 2 weeks, $130.95{\pm}39.24{\mu}m$, $212.39{\pm}89.22{\mu}m$ at the 4 weeks, $181.53{\pm}76.35{\mu}m$ and $257.12{\pm}51.22{\mu}m$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. But, there was no statistically significant difference between the two groups. 2. The area of newly formed bone in the defects was $2962.06{\pm}1284.48{\mu}m^2$, $5194.88{\pm}1247.88{\mu}m^2$ at the 2 weeks, $5103.25{\pm}1375.88{\mu}m^2$, $7751.43{\pm}2228.20{\mu}m^2$ at the 4 weeks and $8046.20{\pm}818.99{\mu}m^2$, $15578.57{\pm}5606.55{\mu}m^2$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. 3. The density of newly formed bone in the defects was $14.26{\pm}6.33%$, $27.91{\pm}6.65%$ at the 2 weeks, $20.06{\pm}9.07%$, $27.86{\pm}8.20%$ at the 4 weeks and $22.99{\pm}3.76%$, $32.17{\pm}6.38%$ at the 8 weeks in the control group and experimental group respectively. At all periods, the means of experimental group was greater than those of control group. The experimental group showed statistically significant difference to the control group at the 2 and 8 weeks. These results suggest that the use of chitosan on the calvarial defects in rats has significant effect on the regeneration of bone tissue in itself

• Journal of Korean Society of Forest Science
• /
• v.102 no.2
• /
• pp.210-215
• /
• 2013

Litterfall production represents a major contribution of carbon and nutrient cycling in forest ecosystems. This study was carried out to determine the litterfall production in a broadleaved deciduous forest at the Mt. Keumsan Long Term Ecological Research (LTER) site, Southern Korea. Littefall was collected monthly or bimonthly from the site for 7 years from 2004 to2010. Leaf and reproductive (catkins) litters showed a seasonal variation, but litters of needle, branch, and barks were not changed across the seasons. Annual leaf litter of Quercus serrata and Carpinus laxiflora were significantly different (p<0.05) but that of C. cordata, Chamaecyparis obtusa, and Pinus thunbergii was not significantly changed for 7 years (p>0.05). Annual average litterfall production was 5,223 kg/ha, but annual variations were very large with minimum of 4,110 kg/ha/yr in 2004 and maximum of 6,002 kg/ha/yr in 2007. Total litterfall comprised of 2,323 kg/ha/yr in Q. serrata, 442 kg/ha/yr in C. laxiflora, 157 kg/ha/yr in C. cordata, 131 kg/ha/yr in Acer pseudosieboldianum, 390 kg/ha/yr in other deciduous tree species, 74 kg/ha/yr in P. thunbergii, 37 kg/ha/yr in C. obtusa, 672 kg/ha/yr in branches, 515 kg/ha/yr in miscellaneous, 448 kg/ha/yr in reproductive parts, and 54 kg/ha/yr in barks. respectively. The results indicate that litterfall production of the Mt. Keumsan LTER site was yearly fructurated with the positive linear relationship between leaf or total litterfall and annual mean temperature if no disturbance such as a typoon, and was lower than that of other Korean LTER sites.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.7
• /
• pp.1077-1081
• /
• 2005

The objective of this study was to investigate the components and nutritional quality of red-tanner crab (Chionoecetes japonicus) paste in order to explore possibility for food processing source such as surimi gel containing crab paste. Yield of crab paste was $30\%$ from whole body after crushing and dehydrating. Crude protein contents $(9.5\%)$ of crab paste was lower than that $(13.1\%)$ of crab muscle, but fat $(0.5\%)$ and ash contents $(8.0\%)$ of paste were higher than $0.2\%\;and\;1.3\%$ of crab muscle, respectively. Volatile basic nitrogen (VBN) content of the crab paste was lower than those of the edible parts. Total amino acid content (9,497mg/l00g) of paste was lower than that (12,980mg/100g) of muscle. Aspartic acid, glutamic acid, lysine and leucine were the predominant amino acids in the protein fraction. The calcium content (6,539mg/l00g) was higher than those of phosphorus (579mg/100g), and potassium (793mg/100g) while manganese and iron were present in trace amounts. Major fatty acids of total lipid were 16:0, 18:1n-9, 20:5n-3 and 22:6n-3, and no difference of composition between paste and muscle. Sensory evaluation showed that scores of color and flavor of $15\%$ substituted surimi gel increased significantly when compared to surimi gel without crab paste (p<0.05). From the above results, the addition of crab paste enhanced nutrition and functionality of surimi gel.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.2
• /
• pp.232-237
• /
• 1994

Changes of volatile components in modified oleoresin red pepper during cooking at high temperature were investigated. Dried red pepper was milled to 100mesh of size particle and oily compounds were extracted by reduced pressure steam distrillation. The rest part was reextracted and concentrated. The extracts were combined. The same volume of water and 4% of polyglycerol condensed ricinoleate (PGDR) were added to the combined extract, and emulsified to make oleoresin red pepper 119 volatile compounds were separated from the dried red pepper and oleoresin and 35 components were identified in both samples. The major flavor compounds were identified to be 2-methoxy-phenol, 2, 6-bis(1, 1-dimethylethyl)-4-methyl-phenol, 1, 4-dimethylbenzene, thylbenzene, 1, 2-benzenedicarboxylic acid, 2-methoxyl-4-methylphenol, 4-ethyl-2-methoxy-phenol, and 5- methyl-2-furancarboxyaldehyde, and their transferal from raw red pepper to oleresin was low. 93 voltilie compounds were isolated after 3 hours cooking at 100 and 82 volitile compounds were separated after that at $150^{\circ}C$. Degeneration of volatile compounds was peculiarly proportional to the temperature of cooling. Capsaicin was relatively stable during cooking and remaining ratio after cooking at 100 and $150^{\circ}C$ was 84.7% and 73.3%. respectively. Oleoresin from red pepper had a little antioxidation effect at $100^{\circ}C$ cooking, but, antioxidation effect at $150^{\circ}C$ cooking was not shown due to degradation of capsaicin.

• Journal of Korean Society of Forest Science
• /
• v.89 no.3
• /
• pp.342-355
• /
• 2000

This study was carried out to reveal the influence of discharge change on matters and stream water quality between pH, EC and dissolved matters obtained by observation of long-term and short-term on stream water quality and separated runoff components from stream water by using HYCYMODEL. From January in 1998 to September in 1999, it was estimated by relationships of character of water quality and discharge for the experimental watershed in Mt. Palgong. The results were summarized as follows : 1. Annual average pH values of stream water in 1998 and in 1999 were 6.48(6.22~6.89) and 6.52(5.75~7.18), respectively. The observed annual average pH values were maintaining identical values in general, but pH values decreased continuously during the four months after thinning in the experimental watershed. So thinning is suspected of the major cause for the decrease. 2. Annual average EC values of stream water in 1998 and in 1999 were $26.69(17.95{\sim}33.5){\mu}S/cm$ and $25.19(17.5{\sim}33.8){\mu}S/cm$, respectively. The observed annual average EC values were maintaining identical values in general. 3. As a result of the comparison of average dissolved ions of rainfall and stream water, $Na^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $NO_3{^-}$, and $SO_4{^{2-}}$ showed minus values between incomings and outgoings. $Na^+$ and $NO_3{^-}$ among the dissolved ions of stream water showed the highest concentration out of cations and anions respectively. 4. By the change of pH value in stream water due to rainfall events, pH value decreased with increasing runoff as pH value increased before and after peak flow. 5. By the change of EC value in stream water due to rainfall events, EC value decreased with increasing runoff of first rainfall as EC value changed with runoff before and after peak flow. 6. As the runoff increased, the concentration of $Na^+$, $Ca^{2+}$, $K^+$, total cation, $Cl^-$, and $SO_4{^{2-}}$ in stream water lowered. On the other hand, the runoff decreased, their concentration in stream water tended to get high. But in terms of $NO_3{^-}$ and total anion, they turned out vice versa. $Mg^{2+}$ produced no reaction. 7. The base flow among runoff components separated by using HYCYMODEL influenced greatly on pH, EC, concentration of cation and anion.

• Journal of Korean Society of Forest Science
• /
• v.85 no.1
• /
• pp.1-14
• /
• 1996

The object of this study was to examine the effects of air pollution on forest vegetation structure in the vinicity of Sasang industrial complex in Korea. Forest vegetation structure was investigated at 19 sample plots surrounding industrial complex and at one site away from industrial complex as a control. The results obtained were as follows; 1. For analysis of vegetation structure, upperstory of forests was mostly consisted of Pinus thunbergii, and partly of Alnus firma and Robinia pseudoacacia. In midstory, major components were Pinus thunbergii, Robinia pseudoacacia, Rhus trichocarpa, Rhus chinensis and Styrax japonica, In lower story, Pinus thunbergii was a minor component, while Robinia pseudoacacia, Quercus serrata, Rhus trichocarpa. and Rhododendron yedoense var. poukhanense which were known to be resistant to air pollution were found in large number. Especially, importance percentage of Robinia pseudoacacia was high, while that of Rhododendron mucronulatum was low in surrounding industrial complex. 2. For woody plants, number of species, species diversity and similarity index in industrial complex, were not significantly different from those in control plot. 3. For herbs, Oplismenus undulatifolius appeared in large number in most plots. The $SDR_3$ of Miscanthus sinensis, Calamagrostis arundinacea, Paederia scandens, Spodiopogon cotulifer and Carex humilis were high, but that of Aster scaber, Saussurea seoulensis, Solidago virgaaurea var. asiatica and Prunella vulgaris var. lilacina were low in the vicinity of industrial complex. 4. Number of herb species decreased to below 10 species at surrounding industrial complex as compared to 20 species in the control plot. In addition species diversity, and similarity index in the industrial complex were lower than those in control plot. It may be concluded that Pinus thunbergii forests in industrial complex consists of tree species resistant to air pollution, and that composition of woody vegetation in industrial complex was not much different from control plot, while composition of herbs was already quite different between the two plots. Forest vegetation structure, therefore, may change with time due to air pollution in the industrial complex.

• KDI Journal of Economic Policy
• /
• v.30 no.2
• /
• pp.157-183
• /
• 2008

'New Universities for Regional Innovation(NURI)' is a financial aid program designed to promote the development of universities as a major component of Regional Innovation System (RIS). In particular, this program emphasizes the role of regional universities to provide the qualified graduates for the regional economy. This paper is to evaluate the effect of NURI, focusing on the change of graduates' employment. The effect of the program can be evaluated by the quality of graduates' accumulated human capital, and graduates' employment performance represents the graduates' quality evaluated in the labor market. This is also believed to be a good performance indicator of the NURI program. We utilize the graduate employment survey of Korean Educational Development Institute (KEDI), and calculate the graduates' employment rates of the departments that received the financial support of NURI (treatment group). We also calculate the graduates' employment rates of the departments that applied for the support of the NURI program but were not selected (comparison group). By using difference-in-differences method, we compare the change of graduates' employment rates in treatment and comparison groups before and after the program came in effect. Compared with the employment rates in 2004 before the NURI program started, the graduates employment rates improved in both groups in 2005 and 2006. The improvement of the employment rates in the treatment group is larger than that in the comparison group. Moreover, the difference of improvement gets larger in the year 2006 than in 2005, which means those students who were affected more years by the NURI program are more likely to be employed. However, the difference is not statistically significant, and we cannot definetely conclude that NURI showed the desired effect on the quality of the college graduates. We calculate employment rates in two ways; whether to treat going on to graduate education as an employment or not. The result was qualitatively the same in both cases. We also tracked quality of employment by investigating the firm size where the graduates of the treatment group were employed. By utilizing data from the Employment Insurance Fund, we measure the firm size by the number of employees. We did not find any deterioration of employment quality between 2005 and 2006, though it deteriorates in 2007. Therefore, the improvement of employment rates until 2006, though not statistically significant, does not seem to come at the cost of employment quality. The interpretation of this result cannot help being very limited. First, this evaluation covers such a short time period. It only covers two years after the program started, 2005 and 2006. Second, the extent of the improvement in employment rates is not satisfactory considering the amount of financial support, even though it can be argued that the employment has improved since the inception of the program. Subsequent evaluation of the program is required to certify the NURI programs' longer term effectiveness.

• Management & Information Systems Review
• /
• v.39 no.1
• /
• pp.93-114
• /
• 2020

Platform is considered as an alternative strategy to the traditional linear pipeline based business. Moreover, in the 4th industrial revolution period, efficiency driven pipeline business model needs to be changed to platform business. We have such success stories about platform as Apple, Google, Amazon, Uber, and so on. However, for those smaller corporations, it is not easy to find out the transformation strategy. The essence of platform business is to leverage network effect in management. Thus platform based management can be rephrased as network management across the business functions. Research on platform business is popular and related to diverse facets. But few scholars cover what the research trend of the domain is. The main purpose of this paper is to identify the research trend on platform business in Korea. To do that we first propose the analytical model for platform architecture whose components are consumers, suppliers, artifacts, and IT platform system. We conjecture that mapping of the research work on platform to the components of the model will make us understand the hidden domain of platform research. We propose three hypotheses regarding the characteristics of research and one proposition for the transitional path from pipeline to platform business model. The mapping is based on the research articles filtered from the Korea Citation Index, using keyword search. Research papers are searched through the keywords provided by authors using the word of "platform". The filtered articles are summarized in terms of the attributes such as major component of platform considered, platform type, main purpose of the research, and research method. Using the filtered data, we test the hypotheses in exploratory ways. The contribution of our research is as follows: First, based on the findings, scholars can find the areas of research on the domain: areas where research has been matured and territory where future research is actively sought. Second, the proposition provided can give business practitioners the guideline for changing their strategy from pipeline to platform oriented. This research needs to be considered as exploratory not inferential since subjective judgments are involved in data collection, classification, and interpretation of research articles.