• Food Science of Animal Resources
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• v.30 no.3
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• pp.495-503
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• 2010

Analyses were conducted to estimate the effect of quality grade on the carcass characteristics, physico-chemical and sensory traits of Longissimus dorsi in Hanwoo. A total of 42,113 carcasses were selected on the basis of five quality grades (grade $1^{++}$, $1^+$, 1, 2, and 3) and an additional 258 samples of Longissimus dorsi were used to evaluate the beef quality. The increase in quality grade from grade 3 to grade $1^{++}$ was significant (p<0.05) for carcass weight (from 338.7 kg to 387.2 kg), backfat thickness (from 7.45 mm to 12.23 mm) and marbling score (from 1.09 to 8.31). In contrast, significantly decreased levels of meat color, fat color, texture and maturity were apparent with increasing quality grade (p<0.05). Increasing quality grade was also correlated with significant increases (p<0.05) in crude fat contents (from 3.57% to 25.68%) and water holding capacity (from 52.41% to 58.03), and a decrease of the Warner-Bratzler shear force from 8.29 kg to 2.83 kg. The highest $L^*$ value (41.53) and highest cooking loss (22.11%) were observed with grade $1^{++}$ and 3 beef, respectively. There was no difference observed on $pH_{24}$ (5.53 to 5.66) among the quality grades, which were within the normal range. Sensory evaluation experiments revealed that quality grades were associated with significantly altered (all p<0.05) tenderness, juiciness, flavor, and overall acceptability. The crude fat contents showed significant correlation with juiciness (r=0.59), tenderness (r=0.71), flavor (r=0.55), and overall acceptability (r=0.69). The lower sensory trait scores were related to higher WBs. Grade $1^+$ Hanwoo beef had a significantly higher WBs and lower fat contents when compared to grade $1^{++}$ Hanwoo beef (p<0.05).

• Food Science of Animal Resources
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• v.30 no.3
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• pp.419-426
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• 2010

This study was conducted to investigate the effect of different castration ages on meat quality and sensory properties of Korean native black goats over 410 days. For the experiment, 32 heads of goat (eight heads/4 treatment) were subjected to either a control (5 month non-castration), T1 (7 month castration), T2 (5 month castration) or T3 (3 month castration). The total weight gain for Korean native black goats was highest in the T2 group after feeding for 410 days and the weight gain/day tended to be similar to the total weight gain. The total feeding amounts were lowest (410.82 kg) in T3; however, the feed intake ratio was 16.39 in T2, indicating that it had the best feed efficiency among groups. The cooking loss and drip loss of the Korean native black goats was highest in the control, being 35.53% and 2.08%, respectively (p<0.05), while the total cholesterol of the treatments was higher than that of the control (p<0.05). Moreover, the overall sensory evaluation of the treatment groups was low, indicating that there was more meat flavor when compared to the controls in terms of juiciness, tenderness, flavor, texture, black goat off-flavor and overall evaluation (p<0.05). T2 was found to have the best meat flavor upon sensory evaluation. Additionally, the meat color of the control showed the highest $L^*$ value and Hue value, while T3 showed the highest $a^*$ value (3.61) and T2 showed the highest $b^*$ value and Chroma. The composition of fatty acids was 53.76% oleic acid in T2, while the amounts of Mono-unsaturated fatty acid (MUFA) were highest in T1 and T2 (p<0.05). As a result, the MUFA/SFA ratios of T1 and T2 were higher than those of the control (p<0.05). In conclusion, it is most advantageous to castrate Korean native black goats at the age of 5 months for the best performance and meat quality.

• Journal of Gifted/Talented Education
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• v.13 no.4
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• pp.65-94
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• 2003

The purpose of this study is to acquire the information on the current situation of students' selection process in order to renovate the system of picking up the students. As a first step of the study, we examined the validity of the factors of the single-out system such as qualification and the process for the application and the standards and proceeding of the selection. Then we analysed the result of the entrance examination of Hansung Science Highschool in 2002. The analysis was on the correlation between the result of entrance examination and the achievement in the school and the decision of the course after graduation. To know on the achievement of the students, we investigated the records of regular tests and asked the teachers' opinion in math and science classes. As a result, we gained the following points: First, the present single-out system has a danger of excluding students who are much talented in science and math field because it is based on students' achievements in middle schools; Second, the new selection system should consider the character and attitude of the applicants in addition to their knowledge; Third, the continuous observation of the teacher in middle school should be an important factor of the picking up system; Fourth, more questions requiring divergent thinking ability and inquiry skill should be developed as selective examination question. Also examination questions should cover the various contents from mathematics to science, and do not affect pre-learning; Finally, the system of present letting all students stand in one line should be changed into that of letting students in various lines. We can consider using multi-step selection system.

• Journal of Nutrition and Health
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• v.52 no.6
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• pp.529-539
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• 2019

Purpose: Sprouts of evening primrose (Oenothera laciniata, OL) were reported to have high contents of flavonoids and potent antioxidant activity. This study examined the antioxidant and antiobesity activities of OL sprouts to determine if they could be a natural health-beneficial resource preventing obesity and oxidative stress. Methods: OL sprouts were extracted with 50% ethanol, evaporated, and lyophilized (OLE). The in vitro antioxidant activity of OLE was examined using four different tests. The antiobesity activity and in vivo antioxidant activity from OLE consumption were examined using high fat diet-induced obese (DIO) C57BL/6 mice. Results: The IC₅₀ for the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging and superoxide dismutase (SOD)-like activities of OLE were 26.2 ㎍/mL and 327.6 ㎍/mL, respectively. OLE exhibited the ferric reducing antioxidant power (FRAP) activity of 56.7 ㎍ ascorbic acid eq./mL at 100 ㎍/mL, and an increased glutathione level by 65.1% at 200 ㎍/mL compared to the control in the hUC-MSC stem cells. In an animal study, oral treatment with 50 mg or 100 mg of OLE/kg body weight for 14 weeks reduced the body weight gain, visceral fat content, fat cell size, blood leptin, and triglyceride levels, as well as the atherogenic index compared to the high fat diet control group (HFC) (p < 0.05). The blood malondialdehyde (MDA) level and the catalase and SOD-1 activities in adipose tissue were reduced significantly by the OLE treatment compared to HFC as well (p < 0.05). In epididymal adipose tissue, the OLE treatment reduced the mRNA expression of leptin, PPAR-γ and FAS significantly (p < 0.05) compared to HFC while it increased adiponectin expression (p < 0.05). Conclusion: OLE consumption has potent antioxidant and antiobesity activities via the suppression of oxidative stress and lipogenesis in DIO mice. Therefore, OLE could be a good candidate as a natural resource to develop functional food products that prevent obesity and oxidative stress.

• Economic and Environmental Geology
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• v.35 no.3
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• pp.179-189
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• 2002

The Geology of the Shizhuyuan W-Sn-Bi-Mo deposits, situated 16 Ian southeast of Chengzhou City, Hunan Province, China, consist of Proterozoic metasedimentary rocks, Devonian carbonate rocks, Jurassic granitic rocks, Cretaceous granite porphyry and ultramafic dykes. The Shizhuyuan polymetallic deposits were associated with medium- to coarse-grained biotite granite of stage I. According to occurrences of ore body, ore minerals and assemblages, they might be classified into three stages such as skarn, greisen and hydrothernlal stages. The skarn is mainly calcic skarn, which develops around the Qianlishan granite, and consists of garnet, pyroxene, vesuvianite, wollastonite, amphibolite, fluorite, epidote, calcite, scheelite, wolframite, bismuthinite, molybdenite, cassiterite, native bismuth, unidetified Bi- Te-S system mineral, magnetite, and hematite. The greisen was related to residual fluid of medium- to coarse-grained biotite granite, and is classified into planar and vein types. It is composed of quartz, feldspar, muscovite, chlorite, tourmaline, topaz, apatite, beryl, scheelite, wolframite, bismuthinite, molybdenite, cassiterite, native bismuth, unknown uranium mineral, unknown REE mineral, pyrite, magnetite, and chalcopyrite with minor hematite. The hydrothermal stage was related to Cretaceous porphyry, and consist of quartz, pyrite and chalcopyrite. Scheelite shows a zonal texture, and higher MoO) content as 9.17% in central part. Wolframite is WO); 71.20 to 77.37 wt.%, FeO; 9.37 to 18.40 wt.%, MnO; 8.17 to 15.31 wt.% and CaO; 0.01 to 4.82 wt.%. FeO contents of cassiterite are 0.49 to 4.75 wt.%, and show higher contents (4.]7 to 4.75 wt.%) in skarn stage (Stage I). Te and Se contents of native bismuth range from 0.00 to 1.06 wt.% and from 0.00 to 0.57 wt.%, respectively. Unidentified Bi-Te-S system mineral is Bi; 78.62 to 80.75 wt.%, Te; 12.26 to 14.76 wt.%, Cu; 0.00 to 0.42 wt.%, S; 5.68 to 6.84 wt.%, Se; 0.44 to 0.78 wt.%.

• Journal of Bio-Environment Control
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• v.13 no.1
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• pp.51-55
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• 2004

The most commonly used inorganic nutrient compositions such as Murashige & Skoog medium have been optimized for heterotrophic growth. Therefore, they may not be optimal for photomixotrophic and photoautotrophic growth of plantlets. In photomixotrophic micropropagation, emdium sugar level is often lowered, while light and $CO_2$ levels in vessel are raised, and chlorophyllous explants are used to facilitate photosynthetic carbon acquisition. In a factorial experiment effect of addition (+) and omission(_) of organic materials (OM, 0.5 g ${\cdot}$ $m^{-3}$ each of thiamine, nicotinic acid and pyridoxine and 100 ${\cdot}$ $m^{-3}$ myo-inositiol) combined with three sucrose levels (0, 15, and 30 kg ${\cdot}$ $m^{-3}$) was tested on the growth of potato plantlets. Each of nodal cuttings with a leaf was cultured on 0.1${\times}$$10^{-4}m^{-3}$) MS agar ( 8 kg ${\cdot}$ $m^{-3}$) medium (pH 5.80 before autoclave) in glass test tubes (100 mm${\times}$25mm) capped with a sheet of transparent film with a 6 mm diameter gas permeable filter (5.1 air exchanges ${\cdot}$$h^{-1}$). Cultures were maintained in a room for 27 days at $23^{\circ}C$, 50% RH, 350-450${\mu}mol\;{\codt}\;mol^{-1}CO_2$, 16 h ${\cdot}$ $d^{-1}$ photoperiod at 13${\mu}mol\;{\codt}\;m\;{\codt}\;s^{-1}$ PPFD provided by white cool fluorescent lamps. Growth of potato plantlet in the +OM and -OM treatments were similar, while medium pH was 0.2 scale lower in the latter. Dry weight, % dry matter, and stem diameter enhanced, while shoot to root dry weight ratio, leaf area, chlorophyll concentration per gram dry weight, and medium pH decreased with increasing initial sucrose level. Interaction between OM and sucrose levels was observed in shoot length and medium pH. Results indicate that OM can be omitted from the medium without detrimental effect while addition of sucrose was beneficial for the photomixotrophic growth of potato plantlets under raised light and $CO_2$.

• Journal of Nutrition and Health
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• v.25 no.2
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• pp.123-131
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• 1992

Concentrations of 5 major minerals(Na, K, Ca, P, Mg) and 3 trace elements(Mn, Mo, Ni) were measured in human milk samples collected from 21 highly selected healty lactating women at 2-5 days and at 1, 2, 4, 6 and 12 weeks postpartum. Significant decrease in contents of the major minerals and trace elements were found with time postpartum. Sodium contents decreased from 293.01ug/N at 2-5 days to 194.27ug/N at 12 weeks. Potassium contents also decreased from 436.18ug/N in colostrum to 358.51ug/N in matured milk at 12 weeks. The Ca/P ratios of colostrum transitional and matured milk were 3.39, 281 and 2.45 respecti-vely. Mean manganese levels of colostrum and transitional were 0.024ug/N and those of matured milk were 0.014ug/N. Molybdenum concentrations in the breast-milk collected at 1, 2, 4 weeks were higher than those in the milk samples at 2-5 days and 12 weeks Nickel content of colostrum was 0.062ug/N and those of trnsitional matured milk were 0.22ug/N and 0.017ug/N, These determinations will provide the basic information on the variability of minerals and trace elements as lactation proceed and the comparison of the components between term and preterm milk.

• Journal of Nutrition and Health
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• v.25 no.2
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• pp.179-186
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• 1992

Dietary intakes of 57 college women were measured by 7-day weight food records(7WR) Nutrient intakes of 7WR were compared with results of using 1-day weighted food records(1WR) and 2-day weighed food records(2WR), 7WR were recorded for 7 consecutive days by subjects and its first two days were chosen to provide 1WR and 2WR Mean nutrient intakes of the group were not significantly different between 1WR or 2WRand 7WR. Within-person variations were found to be greater than between-person variations. The ratio of within- and between-person variability was lowest for the vitamin A and highest for the calcium. Data on 7WR were analyzed to estimate the number of recording days needed to ensure r$\geq$0.9 between observed and turn mean intakes. The 11 to 13 days needed for energy sugar protein and vitamin A and 20 days for calcium The results indicated that the number of days needed varied substantially among individuals for the same nutrient and within individuals for different nutrients.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.47-60
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• 2007

The purpose of this study is to compare and to evaluate the effect of pH and lactic acid concentration on the progression of artificial root caries lesion using polarizing microscope, and to evaluate the morphological changes of hydroxyapatite crystals of the demineralized area and to investigate the process of demineralization using scanning electron microscope. Artificial root caries lesion was created by dividing specimens into 3 pH groups (pH 4.3, 5.0, 5.5), and each pH group was divided into 3 lactic acid concentration groups (25 mM, 50 mM, 100 mM). Each group was immersed in acid buffer solution for 5 days and examined. The results were as follows : 1. Under polarized microscope, the depth of lesion was more effected by the lactic acid concentration rather than the pH. 2. Under scanning electron microscope, dissolution of hydroxyapatite crystals were increased as the lactic acid concentration increased and the pH decreased. 3. Demineralized hydroxyapatite crystals showed peripheral dissolution and decreased size and number within cluster of hydroxyapatite crystals and widening of intercluster and intercrystal spaces as the pH decreased and the lactic acid concentration increased. 4. Under scanning electron microscope evaluation of the surface zone, clusters of hydroxyapatite crystals were dissolved, and dissolution and reattachment of crystals on the surface of collagen fibrils were observed as the lactic acid concentration increased. 5. Under scanning electron microscope, demineralizatlon of dentin occurred not only independently but also with remineralization simultaneously. In conclusion, the study showed that pH and lactic acid concentration influenced the rate of progression of the lesion in artificial root caries. Demineralization process was progressed from the surface of the cluster of hydroxyapatite crystals and the morphology of hydroxyapatite crystals changed from round or elliptical shape into irregular shape as time elapsed.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.2
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• pp.127-136
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• 2010

This study is aimed at reviewed and analyzed in order to suggest the improved plans related to natural monuments. The summary of this study is as followings; First, Replacing the current term 'cultural properties', which denotes the meaning of 'goods', we need to devise an new categorization that separates such properties into cultural heritage and natural heritage under the national heritage framework. Second, the designation criteria for natural monuments should be divided into the individual realm for animals and plants respectively, since they are not divided in the current Act. Third, the guidelines for naming of natural monuments should be established with the following new categories in accordance with the clear standards. Fourth, such imbalances require us to give priority to the relatively neglected types and areas. Fifth, as the big and old trees account for more than a half of the designated plants, it is necessary to search out new resources(wet plant communities, seashores, sand dune plant communities, etc.) such as geological resources, mineral springs, hot springs, and fossils that are in danger of completely being exploited and exhausted. While most of the designated animals are protected nationally, the existing designation system is required to protect habitats and breeding places for the systematic and efficient conservation. Sixth, as long as we need to preserve those historical and cultural resources for the future generations from national and global perspectives, we should enhance their values by designating them as natural monuments even though they are protected by other regulations such as the natural environment area. Seventh, as a result of the survey, we found that more budgets and experts in the local governments, more empowered organizations, more active public participation should be provided for the better Natural Monument management in Korea. Eighth, the Lap of Natural Heritage in the National Research Institute of Cultural Heritage needs to be developed to the Natural Heritage Institute to conduct the diverse activities such as researches, restoration, exhibition and education programs in a systematic and efficient way. Ninth and the last, major damages to natural monuments can be generally categorized into the artificial one and natural one, respectively. The artificial damages include toxics, soil covering, excessive humidity, fire, construction and management works, unlawful damages, fishing, oil spillage, etc, and the natural ones include lightning, storms(typhoons), heavy snowfalls, damage by insects and diseases, lack of prey, etc. This study will become meaningful in that it proposes specific measures for the improvement of the institutions, designation, and management of natural monuments on the basis of the comprehensive analysis on natural monuments. We wish to leave the other subjects related with this study to the future researches.