• Journal of Nutrition and Health
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• v.9 no.1
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• pp.84-91
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• 1976

Chemical determination were made to analyze the concentration of nutrients including proximate composition, vitamins, minerals, amino acids and fatty acids in three kinds of locally produced infantile formula milk(DFM) and one fermented milk(FM). An attempt was also made to compare the analytical values of nutrients against guaranteed values. The results obtained are summarized as follows; 1. The analyzed value of protein and fat content in DFM-A.B.C was slightly lower than that of guaranteed values and a reverse trend was observed in the case of total carbohydrate. There were no differences in proximate composition among the three kinds of DFM. It was found that the FM contained less protein and fat than the fresh milk, but it seemed that a considerable amount of sugar was added to FM. 2. The analyzed values of vitamin $A(2{\sim}3\;times)$ and $E(4{\sim}6\;times)$ contents in DFMS were higher than those of the guaranteed values except niacin. There were a little differences in vitamin contents among DFMS analyzed. 3. In the case of minerals, the analyzed values were similar to the guaranteed values except the calcium concentration that analyzed value was much higher than guaranted value. When the DFMS were diluted to 15% by adding water to compare with the human and fresh cow milk, it was found that the diluted DFMS resembled the human milk rather than cow milk in the content of energy, carbohydrates, protein and ash. The higher contents of iron and most vitamins in the diluted DFMS than the human milk or cow milk would indicate that they were fortificated with these nutrients. When these diluted DFMS were compared with the Korean R.D.A. for infant, it was clear that they could supply sufficient amount of the nutrients required by R.D.A. except the niacin which failed to reach the recommended level. The fact that iron content of DFM-C was not sufficient while vitamin A supply was excessive by 6 fold would indicate that further studies for the improvement may be necessary. 4. There was a little difference among DFMS in amino acid composition. The similarity of the essential amino acids composition between DFMS and cow milk indicated that there was no modification of the essential amino acids. However, present data showed that the amino acid compositon of FM was similar to that of the cow milk. 5. There was no difference among DFMS in the degree of saturation of fatty acids. The similar or higher levels of essential fatty acids contents of DFMS as compared with human milk revealed that essential fatty acids were added to DFMS during the course of process. From the experimental results described above, it may be concluded that the nutritive effects of three kinds of locally produced DFMS were much alike. It was also found that macro and micro nutrient composition except amino acid composition of locally produced dried formula milk was very much similar to that of the human milk. Moreover, fortification of iron and vitamins resulted in improving their nutritive values as the single form of infantile food, but it seemed that more consideration should be given on the fortification of some nutrients.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.1
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• pp.2913-2924
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• 1973

This study was to investigate the drying mechanism of stratified soil by investigating 'effects of the upper soil on moisture loss of the lower soil and vice versa' and at the same time by examining how the drying progressed in the stratified soils with bare surface and with vegetated surface respectively. There were six plots of the stratified soils with bare surface($A_1- A_6$ plot) and the same other six plots($B_1- B_5$ plot), with vegetated surface(white clover). These six plots were made by permutating two kinds of soils from three kinds of soils; clay loam(CL). Sandy loam(SL). Sand(s). Each layer was leveled by saturating sufficient water. Depth of each plot was 40cm by making each layer 20cm deep and its area. $90{\times}90(cm^2)$. The cell was put at the point of the central and mid-depth of the each layer in the each plot in order to measure the soil moisture by using OHMMETER. soil moisture tester, and movement of soil water from out sides was cut off by putting the vinyl on the four sides. The results obtained were as follow; 1. Drying progressed from the surface layer to the lower layer regardless of plots. There was a tendency thet drying of the upper soil was faster than that of the lower soil and drying of the plot with vegetated surface was also faster than that of the plot with bare surface. 2. Soil moisture was recovered at approximately the field capacity or moisture equivalent by infiltration in the course of drying, when there was a rainfall. 3. Effects of soil texture of the lower soil on dryness of the upper soil in the stratified soil were explained as follows; a) When the lower soil was S and the upper, CL or SL, dryness of the upper soils overlying the lower soil of S was much faster than that overlying the lower soil of SL or CL, because sandy soil, having the small field capacity value and playing a part of the layer cutting off to some extent capillary water supply. Drying of SL was remarkably faster than that of CL in the upper soil. b) When the lower soil was SL and the upper S or CL, drying of the upper soil was the slowest because of the lower SL, having a comparatively large field capacity value. Drying of CL tended to be faster than that of S in the upper soil. c) When the lower soil was CL and the upper S or SL, drying of the upper soil was relatively fast because of the lower CL, having the largest field capacity value but the slowest capillary conductivity. Drying of SL tended to be faster than that of S in the upper soil. 4. According to a change in soil moisture content of the upper soil and the lower soil during a day there was a tendency that soil moisture contents of CL and SL in the upper soil were decreased to its minimum value but that of S increased to its maximum value, during 3 hours between 12.00 and 15.00. There was another tendency that soil moisture contents of CL, SL and S in the lower soil were all slightly decreased by temperature rising and those in a cloudy day were smaller than those in a clear day. 5. The ratio of the accumulated soil moisture consumption to the accumulated guage evaporation in the plot with vegetated surface was generally larger than that in the plot with bare surface. The ratio tended to decrease in the course of time, and also there was a tendency that it mainly depended on the texture of the upper soil at the first period and the texture of the lower soil at the last period. 6. A change in the ratio of the accumulated soil moisture consumption was larger in the lower soil of SL than in the lower soil of S. when the upper soil was CL and the lower, SL and S. The ratio showed the biggest figure among any other plots, and the ratio in the lower soil plot of CL indicated sligtly bigger than that in the lower soil plot of S, when the upper soil was SL and the lower, CL and S. The ratio showed less figure than that of two cases above mentioned, when the upper soil was S and the lower CL and SL and that in the lower soil plot of CL indicated a less ratio than that in the lower soil plot of SL. As a result of this experiments, the various soil layers wero arranged in the following order with regard to the ratio of the accumulated soil moisture consumption: SL/CL>SL/S>CL/SL>CL/S$\fallingdotseq$S/SL>S/CL.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.381-395
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• 2008

Purpoose: For decades dental implants have been used widely in the field of prosthetic dentistry. However there is confusion when establishing treatment plans in cases where some teeth are remained but an insufficient number of implants can be used due to limited anatomical status and ecomomical problems. Many clinicians have tried to connect natural teeth and implants, and it still has controversy. But, there have been few studies on mechanical analysis of connecting natural teeth and implants with konus telescopic removable partial dentures. The purpose of this study was to analyze the stress distribution of prosthesis, abutment and alveolar bone when teeth and implants were connected with the konus telescopic denture, by means of 3-dimensional finite element analysis. Material and methods: The assumption of this study was that there were 2 mandibular canine (11 mm in length, 4 mm in diameter) and 2 implants(10 mm in length, 4 mm in diameter) which are located in the second premolar region. The mandible, teeth, implants, abutments, and connectors are modeled, and analyzed with the commercial software, ANSYS Version 8.1(Swanson, Inc., USA). The control group used implants instead of natural teeth. 21038 elements, 23544 nodes were used in experimental group and 107595 elements, 21963 nodes were used in control group, Stress distribution was evaluated under 150 N vertical load on 3 experimental conditions - between teeth and implants (Load case 1), posterior to implants (Load case 2), between natural teeth (Load case 3). Results: 1. In all load cases, higher von mises stress value was observed in the experimental group. 2. Maximum von miss stress observed in all load cases and all locations were as follows ; a. 929.44 Mpa in the experimental group, 640.044 Mpa in the control group in outer crown and connector - The experimental group showed 1.45 times high value compared with the control group. b. 145,051 Mpa in the experimental group, 142.338 Mpa in the control group in abutment - The experimental group showed 1.02times high value compared with the control group. c. 32.489 Mpa in the experimental group, 25.765 Mpa in the control group in alveolar bone - The experimental group showed 1.26times higher value compared with the control group. 3. All maximum von mises stress was observed in load case 2, and maxim von mises stress in alveolar bone was 32.489 Mpa at which implant failure cannot occur. 4. If maximum von mises stress is compared between two groups, the value of the experimental group is 1.02 times higher than the control group in abutment, 1.26 times higher than the control group in alveolar bone. Conclusion: If natural teeth and implants are connected with the konus telescopic denture, maximum stress will be similar in abutment, 1.26 times higher in alveolar bone than the control group. With this result, there may be possible to make to avoid konus telescopic dentures where natural teeth and implants exist together.

• Korean Journal of Weed Science
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• v.10 no.4
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• pp.294-304
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• 1990

For the survey of weed distribution in the cultivated upland of Korea, weed species were investigated at 2 field by crop of 2 myon per kun in 81 kun selected among the 139 kun of the whole country. 232 species in 46 families were observed, totally. From among the result, 165 species in 39 families the in winter crop field, 189 species in 41 families in the summer crop field were classified. 122 species in 34 families were emerged the from the upland crop field of the whole season. Further more, in the 10 dominant weed species which emerged from upland crop field, Alopecurus aequalis, Chenopodium album, slellaria media, Galium spurieum, Capsella bursa-pastoris and Rorippa islandica were dominated in the winter upland and paddy field, and that Erigeron canadensis, Cyperus amuricus, Equisetum arvense and Arenaria serpyllifolia were dominated in the winter upland field, additionally. Stellaria alsine, Bothriospermum tenellum, Trigonotis peduncularis and Polygonum arviculare were dominated in the winter cropping on drained paddy field, additionally. In the summer crop field, Digitaria sanguinalis, Portulaca oleracea, Acalypha australis, Echinochloa crus-galli, Setaria viridis, Persicaria hydropiper, Amaranthus lividus, commelina communis, Chenopodium album and Cyperecs amuricus were dominated.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.923-932
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• 2003

This study was carried out to estimate the effects of breed and environment such as sex, test station, test year, test season, parity, initial and final weight on average daily gain, age at 90kg, backfat thickness, feed efficiency, lean percent and selection index on the basis of the performance data collected from 25,790 pigs of Duroc, Yorkshire and Landrace breeds which were performance-tested at the Korea Swine Testing Station from 1991 to 2002. The results obtained in the study are summarized as follows; 1. The means of the major economic traits were estimated as 959.95${\pm}$0.699g for average daily gain, 138.36${\pm}$0.072days for age at 90kg, 1.41${\pm}$0.001cm for backfat thickness, 2.33${\pm}$0.001 for feed efficiency, 56.71${\pm}$0.018% for lean percent and 221.65${\pm}$0.113 for selection index. 2. The effect of breed was statistically significant for all studied traits. Briefly, Duroc showed the best performance for the average daily gain and age at 90kg. Landrace had the best performances for the backfat thickness and lean meat percent. In feed efficiency and selection index, Yorkshire had a better score than other breeds. 3. The least-squares means of female and male for the traits studied were 923.05${\pm}$1.289g and 974.53${\pm}$0.856g for average daily gain, 139.74${\pm}$0.145days and 137.21${\pm}$0.097days for age at 90kg, 1.49${\pm}$0.002cm and 1.39${\pm}$0.002cm for backfat thickness, 2.43${\pm}$0.002 and 2.28${\pm}$0.002 for feed efficiency, 56.43${\pm}$0.034% and 56.81${\pm}$0.023% for lean percent and 211.37${\pm}$0.194 and 224.61${\pm}$0.129 for selection index. Therefore, males were superior to females for all traits examined. 4. The effect of test station was statistically significant for all traits except for selection index. Performances for age at 90kg, backfat thickness, feed efficiency and lean meat percent collected from Test station 2 were higher than those from Test station 1. However, Test station 1 showed better average daily gain. 5. The initial weight and final weight included as a covariate in this study had a significant influence on average daily gain, age at 90kg, backfat thickness, feed efficiency and selection index. From the absolute values of the estimated regression coefficients, it was inferred that the final weight had greater effect for the investigated traits than the initial weight.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.199-208
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• 1977

Activities of various hydrolytic enzymes produced by three plant pathogenic fungi, Sclerotium rolfsii Sacc., Sclerotinia sclerotiorum (Lieb.) deBary and Helminthosporium sigmoideum var. irregulare Crallery et Tullius, were measured. Activties and amounts of the enzymes in mycelia, cultural filtrates, and sclerotia(except of sclerotia of H. sigmoideum var. irregulare) were estimated at various pH levels in order to find out optimal pH for their enzymatic activities. Enzymes such as cellulase (ex), invertase, xylanase, $\beta-amylase$, polymethylgalacturonase, polygalacturonase, phosphatase and protease were estimated. Culture solution for production of enzymes was prepared by adding of 10g, D-glucose, 1.3g $NH_4NO_3,\; 0.5g\; MgSO_4,\;7H_2O,\; and\; 1.0g\; KH_2PO_4$ into 1 liter of potato decoction plus 2ml of micro element solution consisting of 0.2mg. Fe, 0.2mg Zn, and 0.1mg Mn as the sulphates into 1 liter of distilled water. All tested mycelia and cultural filtrates were obtained from the cultures incubarted in previous solution for ten days at $25^{\circ}C$, and sclerotia were harvested from PDA plates of 3. days old, The crude enzyme solutions were prepared according to the method of Miyazaki etal. Ten days after incubation, activities of Cx produced by Scl. sclerotiorum were higher than those of the other fung and each of Cx from three fungi showed different pH optima, such as S. rolfsii and Scl. schlerotiorum in acid side (around pH 3.0), H. sigmoideum var. irregulare in neutral side (around pH 6.3). Invertase activities of S. rolfsii were 20 times higher than those of the other fungi in all samples. All tested fungi, however, showed no significant difference between the enzymatic activities of their cultural filtrate and mycelia and the activities in sclerotia of S. rolfsii and Scl. sclerotiorum were hardly recognized. There were multiple peaks on the xylanase activity curves of three fungi in terms of pH values. High activities of the xylanase were revealed in sclerotia of S. rolfsii and Scl. sclerotiorum, and in mycelia of H. sigmoideum var. irregulare. The highest activities of $\beta-amylase$ were shown both in mycelia and cultural filtrate of H. sigmoideum var. irregulae among the tested fungi, and their optimal pH was 6.2 in both mycelia and cultural filtrate. In the S. rofsii and Sel. sclerotiorum, however, the activities of cultural filtrates were higher than those of the other fungi, and optimal pH was 3.0 and 6.2 for cultural filtrate and both mycelia and sclerotia, respectively. Activities of PMG were high in cultural filtrates of all tested fungi, especially in Scl. sclerotiorum and H. sigmoideum var. irregulare. Mycelia of themalso showed the considerable activities. Optimal pH for enzymatic activities were variable with thekind of fungi or with the samples measured. The highest activities of PG were presented by mycelia of S. rolfsii and Scl. sclerotiorum. $9.l\mu /min.\; and\; 9.5\mu g/min.$, respectively. Optimal pH for activity of PG in mycelia was around 4.5 in S. rolfsii and around 3.0 in Scl. sclerotiorum. Phosphatase of S. rolfsii and Scl. sclerotiorum was more active in acid side (optimal PH3. 5) and that of H. sigmoideum var. irregulare showed one peak each in acid, neutral and alkaline side. But the highest peak was at pH 9.5. Protease of all tested fungi was more active at pH 10.0, especially that of the cultural filtrate of H. sigmoideum var. irregualre.

• Journal of Korea Technology Innovation Society
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• v.10 no.1
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• pp.73-97
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• 2007

R&D into future technologies should be conducted in conjunction with technological innovation strategies that are linked to corporate survival within a framework of information and knowledge-based competitiveness. As such, future technology strategies should be ensured through open R&D organizations. The development of future technologies should not be conducted simply on the basis of future forecasts, but should take into account customer needs in advance and reflect them in the development of the future technologies or services. This research aims to select as segmentation variables the customers' attitude towards accepting future telecommunication technologies and their value orientation in their everyday life, as these factors wilt have the greatest effect on the demand for future telecommunication services and thus segment the future telecom service market. Likewise, such research seeks to segment the market from the stage of technology R&D activities and employ the results to formulate technology development strategies. Based on the customer attitude towards accepting new technologies, two groups were induced, and a hierarchical customer segmentation model was provided to conduct secondary segmentation of the two groups on the basis of their respective customer value orientation. A survey was conducted in June 2006 on 800 consumers aged 15 to 69, residing in Seoul and five other major South Korean cities, through one-on-one interviews. The samples were divided into two sub-groups according to their level of acceptance of new technology; a sub-group demonstrating a high level of technology acceptance (39.4%) and another sub-group with a comparatively lower level of technology acceptance (60.6%). These two sub-groups were further divided each into 5 smaller sub-groups (10 total smaller sub-groups) through two rounds of segmentation. The ten sub-groups were then analyzed in their detailed characteristics, including general demographic characteristics, usage patterns in existing telecom services such as mobile service, broadband internet and wireless internet and the status of ownership of a computing or information device and the desire or intention to purchase one. Through these steps, we were able to statistically prove that each of these 10 sub-groups responded to telecom services as independent markets. We found that each segmented group responds as an independent individual market. Through correspondence analysis, the target segmentation groups were positioned in such a way as to facilitate the entry of future telecommunication services into the market, as well as their diffusion and transferability.

• Ocean and Polar Research
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• v.42 no.3
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• pp.233-247
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• 2020

This study was carried out at 5 sites 11 times over two years to identify the variation of benthic environments and benthic polychaetous community and analyze the benthic healthiness in Dangdong Bay, a small semi-enclosed inner bay of Jinhae Bay. The temperature of bottom water showed the typical temporal fluctuation of a temperate zone and was in the range of 5.94 ~ 23.94℃. The salinity did not change significantly during the study period and was in the range of 32.93 ~ 35.72 psu. The concentration of dissolved oxygen of bottom water fluctuated a great deal and was in the range of 0.31 ~ 10.20 mg/L. The lowest DO value was recorded in July 2015, as 0.31±0.04 mg/L corresponding to the hypoxic water mass. The hypoxic water mass was formed continuously at some sites also in July and August 2016. The mean grain size was in the range of 7.57 ~ 9.81Ø and the average was 8.89±0.20Ø. The surface sediments were mainly composed of fine sediment (mud) above 85%. The mean of TOC was 3.09±0.22% and LOI was 13.30±0.47%, showing very high levels in Korean coastal waters. The concentration of AVS was in the range of 0.33 ~ 1.28 mgS/g-dry. The high values of organic contents and AVS indicated that there had been the serious organic enrichment in Dangdong Bay. The number of species and the density of the benthic polychaetous community in Dangdong Bay were in the range of 2 ~ 38 species and 2 ~ 2,185 ind./㎡ during the study period. The number of species and density were highly sustained in winter and spring, and then decreased gradually with the formation of a hypoxic water mass in summer, and the lowest number of species and density were recorded in autumn. In September and November 2015, the dead zone expanded to almost the whole study area. Dominant polychaetous species were Capitella capitata, Lumbrineris longifolia, Paraprionospio patiens and Sigambra tentaculata, each known as opportunistic species and potential organic pollutant indicator species. In particular, Paraprionospio patiens showed a very high population density of 2,019 ind./㎡ in December 2016. Polychaetous communities at each sampling time were classified into 4 temporal groups according to dominant species in each period by cluster analysis and nMDS. 'Period Group AI' was formed in winter and spring of 2015, dominated by Capitella capitata, 'Period AII' in summer dominated by Lumbrineris longifolia, 'Period B' in autumn with no fauna in the dead zone, and particularly 'Period C' in winter of 2016 dominated by Paraprionospio patiens. As a result of analysis of benthic healthiness, the study area was estimated to be in a Fair~Very Poor condition by AMBI and in a Poor~Very Poor condition by BPI during the study period. Both AMBI and BPI showed that the study area was in a Very Poor condition in September and November 2015, and when the dead zone occurred. In Dongdong Bay, the fact that the formation of a hypoxic water mass occurred in summer and a dead zone in autumn were confirmed. In addition, the dominance of opportunistic and organic pollutant indicator species was also observed clearly. The benthic healthiness indexes such as AMBI and BPI showed that organic enrichment was serious in Dangdong Bay.

• Journal of Korean Academy of Nursing
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• v.26 no.2
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• pp.387-398
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• 1996

The objective of this study was to clarify whether there are any differences between normal and over-weight middle-aged(40∼59yrs)women in their perceived weight, health status, health conception and health behavior choices. The sample consisted of 39 normal weight and 55 over-weight (11％ above on the Body Index Scale) women who live in Juan, Inchon. The Participants were randomly selected in each weight group considering socio-demographic factors. The findings from this study are summarized below. 1) Among the 55 overweight middle-aged women, 16 were above 20％ on the Body Index Scale and 14 were above 30％. Twenty-five(45.5％) of the overweight group and 12(30.8％) of the normal weight group had one disease, and there were 12(21.8％) in the overweight group and 8(20.5％) in the normal weight group where one of the family members had a disease, but these differences were not statistically significant. The average monthly family income for the overweight group was ￦l,880,000 compared to ￦2,140, 000 for the normal weight group, but this difference was also not significant. The age range for the whole group was between 40 and 59(mean＝46.8 for total, 48.6 for overweight and 45.7 for normal weight group). Again no significant difference found. Occupations were housemaker 53(56.4％), private business(13.8％), salarywoman(9.6％), and teacher (2.1％). Thirty housemaker(54.5％) from the overweight group and 23(59％) from the normal group did not constitute a statistically significant different. For the educational status, 34(61.8％) of the overweight women and 33(84.6％)of the normal weight group finished high school or more educational courses, but there was no significant statistical difference. Eleven(20.0％) of the overweight women and 5(12. 8％) of the normal weight group were single, but again no significant statistical difference was found. 2) A test for difference in health characteristics between two weight groups indicated that two groups do not show statistical differences in their perceived health status, health conception or health behavior choice. That is, the overweight group, also perceive their health status as good as the normal group, and regard ‘Health’ as a state that enables them to carry out social roles and functions rather than as the traditional concept of health as no disease or no symptoms. Moreover. the overweight group selected their health behaviors not for the prevention of diseases or maintenance of health but for promotion of health. To determine if no statistical difference might be related to the overweight group's failure of perceive themselves as overweight, the perceived and objective overweight status were compared by the chi-square analysis, and no difference was found（X/sup²＝49.37, df＝1, p＝.000）. However, 7(17.9％) of the normal group perceived themselves as being overweighted and 7(12.7％) of the overweight group thought they were of normal weight. Even though the overweight group employed in this study perceived themselves as being overweight, they regarded themselves as healthy as those in the normal weight group. It was shown that there was no statistical difference between two groups in health conception, and that they chose health behaviors to promote health status. 3) Perceived health conception was shown to be significantly related to health behavior choice （r＝ .28, p＝.006 for whole group : r＝.33, p＝.014 for overweight group : and r＝.12. p＝.463 for normal group） .There was an indication that the more complicated the perceived health conception was, the more the trend of health behavior choice to promote health. This was especially true for the overweight group. But, the perceived health status did not related to health behavior choice statistically（r＝.13, p＝.202）, and it was thought that reasons for selecting health behaviors were not related to their health status. That is, the overweight group perceive themselves as healthy as the normal weight group or thought that overweight itself does not incur any risk on their health. Data from two groups were combined and analyzed with multiple regression methodology, because the relationship pattern of the two groups was similar. The analysis showed that health behavior has a significant relationship with age and the perceived health conception（r/sup²＝.1517, p=.05, F＝8.133）. It means they come to health behavior along with their health conception and their age rather than their weights, perceived weight, health status or other social characteristics. This study was intended to understand how overweight middle-aged women perceive ‘weight’ and ‘health’, and how they meet their health related needs in comparison with normal weight middle-aged women. Other factors related to the health behavior in overweight middle-aged woman need to be determined through further descriptive studies outlined in the following recommendations. a) Reseach with the study area expanded. b) Reseach with grouping more detailed : much more overweight and underweight group c) Reseach on restricted relationship between overweight and age or profession. d) Reseach on what overweight middle-aged women do to reduce their weight and what factors motivate them to do it

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.359-369
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• 2007

This in vitro study was performed to assess the effect of surface sealing on the microleakage of class V composite resin restorations that underwent several aging treatments. Class V cavities were prepared on the buccal surface of 100 sound extracted premolars and restored with a hybrid light-cured composite resin according to the manufacturer's instructions. They were randomly divided into two groups consisting of 50 samples: group I, without surface sealing, and group II, in which margins were etched and surface sealant was applied. After thermocycling, each group was divided into five subgroups, respectively, to represent the five aging treatments: group A = no further treatment (only thermocycling), B = toothbrushing, C = load cycling, D = toothbrushing followed by load cycling, and E = aging treatment in deionized water for six months. Microleakage was assessed by examining the penetration of 2% methylene blue dye. The following results were obtained: 1. At occlusal and cervical margins in groups without surface sealing, there was no significant difference in microleakage after the several aging treatments (p>0.05). 2. The occlusal margins of groups with surface sealing showed no significant differences after the several aging treatments (p>0.05). 3. In the cervical margins of groups with surface sealing, microleakage significantly increased after load cycling or aging in deionized water for six months (p<0.05). 4. The no-further-treatment group and the toothbrushing group with surface sealing showed less microleakage than the corresponding groups without surface sealing (p<0.05). 5. The surface-sealed groups with load cycling or aging in deionized water showed no significant difference in microleakage to the corresponding groups without surface sealing (p>0.05). In conclusion, the results of this study suggest that the surface sealant infiltrating through the gap of the cervical margin exerted a positive effect on microleakage at the initial stage, but the effect was not sufficient to overcome the stress generated by the cuspal flexure during occlusal loading and water absorption.