• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.185-198
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• 2016

Korea has put in significant efforts to increase the number of wildlife crossings between fragmented habitats to prevent loss of biodiversity and to encourage the habitat connectivity in Korea. However, there is a lack of biological data on the effect of vegetation structure in these wildlife crossings and guidelines for design and management of wildlife crossing structures in Korea. Therefore, we selected ground beetle assemblages as model organisms to compare the effect of vegetation structure in wildlife crossings, i.e. bare ground- and shrub-type corridors, in agro-forested landscapes. For this study, 4,207 ground beetles belonging to 33 species were collected through pitfall trapping along the northern forest-corridor-southern forest transects from late April to early September in 2015. Dominant species, abundance, and species richness of ground beetles were significantly higher in the shrub-type corridors than the bare ground-type corridors. Also, the species composition of bare ground-type corridor was significantly different compared to the other habitats such as shrub-type corridor and forests. Similarly, environmental variables were also influenced by vegetation management regimes or trap locations. Collectively, our study clearly indicates that the movement of forest associated ground beetles between forest patches can increase as the vegetation in wildlife crossings becomes complex. Although further studies are needed to verify this, there are indications that the current wildlife crossings that comply with the guidelines may be unfriendly to the movement of ground dwelling arthropods as well as ground beetles. To enhance the ecological function of wildlife crossings, the guidelines need to be rectified as follows: 1) Shrubs or trees should be planted along the corridor verges to provide refuge or movement paths for small mammals and ground dwelling arthropods, and 2) Open spaces should be provided in the middle of the corridors to be used as a path for the movement of large mammals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.378-382
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• 2000

The effects of bisphenol A (BPA), known as one of the endocrine disrupting chemicals (EDCs), on the hatching of fertilized eggs (FE) and the spawning of adult fish in songsari, Oryzias latipes were investigated. In condition of the experimental groups, incubated water temperature was $25.0{\pm}0.5^{\circ}C$ and photoperiod was 16 h (light) : 8 h (dark). fE were exposed to aqueous solutions of BPA at nominal concentration of 50, 100 and $200 {\mu}g/l$. The time required in hatching of FE was long in the BPA $50 and 100 {\mu}g/l$ treatment groups when compared to the controls, and in the BPA $200 {\mu}g/l$ treatment group, FE failed to hatch. And also hatching rate was decreased in the BPA treatment groups in comparison to the controls, Adult fishes were reared to oral administration via a diet of 50, 100 and $200 {\mu}g/g$ body weight BPA concentration for 3 weeks, Number of total eggs spawned in the adult fish were fewer in the BPA 100 and 200 treatment groups than in the controls and BPA 50 treatment group. Frequency of abnormal eggs in the total eggs spawned was 11.8 and $16.2{\%}$ in the control and acetone carrier control lower than 36.8, 46,8 and $74.1{\%}$ in the BPA 50, 100 and 200 treatment groups, respectively. And hatching rate of FE decreased in the BPA treatment groups in comparison to the controls. In these results, inhibition of the hatching of FE and the quantity and quality of spawned eggs in adult fish were observed from BPA treatment groups when compared to the controls.

• Food Science and Preservation
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• v.22 no.6
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• pp.920-925
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• 2015

The microbial composition in Nuruk, a Korean cereal fermentation starter, is a critical factor for the quality and organoleptic properties of traditional alcoholic beverages. This study was aimed at monitoring the compositional change and enzyme activity of culturable lactic acid bacteria (LAB) in two types of Nuruk fermented at different temperatures. All culturable LAB were isolated at various time points (0, 3, 6, 10, 20, and 30 days) and identified by 16S rRNA sequencing. In traditional Nuruk type A (TN-A), which was fermented at $36^{\circ}C$, the population of total culturable LAB during the fermentation period was between $10^4$ and $10^5$ log CFU/mL. On the other hand, the LAB population in traditional Nuruk type B (TN-B) fermented at $45^{\circ}C$ (primary fermentation for 10 days) and $35^{\circ}C$ (secondary fermentation for 20 days) was $10^2$ log CFU/mL; however, these bacteria could not be detected after 6 days. Major LAB strains were identified in both Nuruk types: (1) from the MRS-culture of TN-A, Pediococcus pentosaceus at 3-30 days; (2) from MRS-culture of TN-B, P. pentosaceus at 3 days and Enterococcus hirae at 6 days. The protease activities of the dominant LAB isolated from the TN-A and TN-B cultures were within the ranges of 0.64~1.03 mg/mL and 0.74~0.81 mg/mL (tyrosine content), respectively, whereas the ${\alpha}$-amylase activities were 0.75~0.98 mg/mL and 0.78~0.79 mg/mL (amylose content), respectively.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.240-246
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• 2002

The seasoned pork with soy sauce(SS) or Kochujang(SK) was manufactured using hind and fore leg as main raw material and the quality characteristics and shelf-life were investigated during storage at 5$\^{C}$ and 10$\^{C}$ after having packaged with air. The initial total aerobic plate counts(APC) of SS and SK were 5.24 and 5.75 log10 CFU/㎠, respectively. APC exceeded 7 log10CFU/cm2 after 10 days at 5$\^{C}$ and 6 days at 10$\^{C}$ far SS, and after 6 days at 5$\^{C}$ and 4 days at 10$\^{C}$ for SK, respectively. In the sensory test, the SS samples stored at 5$\^{C}$ and 10$\^{C}$ were assessed as lower than 3.0 points, the criterium of consumer acceptability, after 10 and 8 days, respectively. In the case of SK samples, the point of this time was at day 10 and 6, respectively when they were stored at 5$\^{C}$ and 10$\^{C}$. As storage time extended, pH and water content tended to decrease. Contrarily, the increase of TBA and VBN values was observed during storage and this was more pronounced at 10$\^{C}$ than at 5$\^{C}$ . The oxygen concentration in the package was 19.8 and 19.9% each for 55 and SK samples at the beginning but it was gradually decreased thereafter. On the other hand, the concentration of carbon dioxide was increased with the extension of storage. Based on the above results, the shelf-lives of seasoned pork were estimated to be 8 days for SS and SK stored at 5$\^{C}$ and 6 days for SS and 4 days for SK stored at 10$\^{C}$.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.2
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• pp.93-104
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• 2015

Purpose: This study aimed to analyze the research trends of Ophthalmic Optic by targeting the papers published in the Journal of Korean Ophthalmic Optics Society and serve it as a basis for future researches. Methods: This study was conducted through a statistical analysis of the general characteristics, researcher characteristics, research characteristics and the research trends from total 990 papers, from the first issue to the last issue in 2014, published in the Journal of Korean Ophthalmic Optics Society. Results: Most common number of the authors of the published papers were two or three, respectively 26.8%. Most of the lead authors belong to the schools in Jeolla-do province (31.3%). Most of the educational system of which lead authors belong to is four-year-course system (43.0%). Most common research methods were optometric tests (40.9%). The most common subjects of researches are about the field of optometry (29.8%). The study shows that there were significant differences in the research methods depending on the school systems of the universities to which the lead authors belong (p=0.000). There also were significant differences in the school systems of the universities to which the lead authors belong, and research methods depending on the research subjects (p=0.000). There were meaningful differences according to the period divisions (1996 to 2004 and 2005 to 2014), i.e. the number of authors has been growing, and it is the same case for the number of the authors who belong to four-year-course universities (p=0.000). The number of papers on optometry and contact lenses have increase. The benefits of the research funds have also increased (p<0.005). In addition, the number of the lead authors in the Seoul and Chungcheong province have increased (p=0.000). Conclusions: For the development of the Ophthalmic Optics, it is necessary to broaden the stratum of researchers and deal with various research topics, And joint efforts between eyewear industry and academia and international cooperations are needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.849-858
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• 2007

This study was intended to collect the baseline information on health status, nutrient intakes and dietary self-efficacy according to the obesity levels of male workers. Nutrient intakes of 224 male workers were assessed by 24 hr recall method; also, dietary attitude and dietary self-efficacy were investigated by self-administerd questionnaires. Biochemical characteristics such as blood pressure (SBP, DBP), total cholesterol(TC), hemoglobin (Hb), blood glucose (BG), SGOT, SGPT and ${\gamma}-GTP$ were assessed. Subjects were divided into normal, overweight and obese groups by body mass index (BMI). The health status was analyzed as normal group, health concerned group and disease suspected group. Weight, percent ideal body weight (PIBW), BMI and body circumference (waist, hip) and waist-hip ratio were high in the order of obese group, overweight group and normal group. Body fat mass was high also in the order of obese, overweight and normal group. Blood pressure (SBP, DBP) was the highest in obese group. SGOT, SGPT, ${\gamma}-GTP$ were higher in the obese group than normal and overweight groups. It was Proven that the percentage of those evaluated as low nutrient intakes were 71% for Ca, 50.9% for Zn, 70.5% for vitamin B2, 56.3% for vitamin C and 81.3% for folic acid. The dietary attitude scores were high according to the dietary self-efficacy. The age was positively correlated with dietary attitude, and the dietary attitude was positively correlated with dietary self-efficacy and total energy intakes. Dietary attitude showed the greatest total causal effect in relation to dietary self-efficacy. The results of this study showed some health problems and nutritional problems, indicating the need for nutritional management for male workers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1263-1270
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• 2007

This study was carried out to investigate the effect of green tea product (GTP) on the risk factors of atherosclerosis in ovariectomized (OVX) rats. Sprague-Dewley female rats (10 weeks) weighing approximately $279{\pm}2g$ were divided into 4 groups: sham operated control group treated with high cholesterol diet (Sham-C), OVX control group treated with high cholesterol diet (OVX-C), OVX-G 5% group treated with high cholesterol containing 5% GTP and OVX-G 20% group treated with high cholesterol diet containing 20% GTP. Serum TG concentrations was lower in OVX-G 20% group than in the OVX-C group, whereas ratio of HDL-cholesterol to total cholesterol (%) was significantly (p<0.05) increased in the 20% GTP supplementation group than in the Sham-C and OVX-C groups. Tumor necrosis $factor-{\alpha}$ levels were significantly (p<0.05) decreased in the OVX-G 20% group. Hepatic TG levels were significantly (p<0.05) lowered in OVX-G 20% group than in the other groups. Glutathione levels and antioxidant enzyme activities including glutathione-reductase and Mn-superoxide dismutase in liver were significantly (p<0.05) higher in the OVX-G 20% group in the OVX-C group. Fecal total cholesterol concentrations were increased in the GTP supplementation groups than in the OVX-C group. From the above results, it is concluded that GTP may reduce the risk of atherosclerosis via hypolipidemic action. Therefore, it may be used to possibly improve the hyperlipemia in menopausal women.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.108-117
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• 1994

Twenty nine children with autism and thirty children with mental retardation were examined for association between autism and chromosomal disorders including fragile X. The peripheral blood was cultured in Medium 199 with methotrexate and without methorexate for 70 hours. Thirty metaphase cells in each case were karyotyped in all samples. Chromosomal abnormalities were found in 11 cases(37.9%) of autistic disorder and 10 cases (33.3%) of mental retardation, but in none of fragile(X)(q27.3) from all cases. Chromosomal abnormalities were present on group A, C, D and X in autistic disorder and on group A, B, C, D, E and X in mental retardation. No specific chromosomal region was found in both autistic disorder and mental retardation. Types of chromosomal disorders were only fragile and/or gap but no numerical abnormality was present in all cases. Number of cells which revealed fragile sites were 31 cells(3.6%) out of 870 cells in autistic disorder and 29 cells(3.2%) out of 900 cells in mental retardation Number of cells which revealed gaps were 43 cells(4.9%) out of 870 cells in autistic disorder and 35 cells(3.9%) out of 900 cells in mental retardation. Autistic disorder may not be directly correlated with fragile X but with nonspecific chromosomal breakages from these data.

• The Journal of Korean Academy of Prosthodontics
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• v.19 no.1
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• pp.17-27
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• 1981

This study was conducted to determine the chemical composition and the mechanical properties of four commercially available low gold-based crown and bridge alloy produced in Korea. Four dental casting gold-silver-palladium alloys, i.e., A, B, C and D (code of alloys) were selected for the evaluation of chemical composition, ultimate tensile strength, elongation. values and Vickers hardness. The chemical composition of test specimens was analyzed by both emission spectrography and wet gravitation method with a 1.5gm of low gold ingot. The tensile properties and Vickers hardness was determined with cast specimens treated in following three conditions; as-cast, softening heat treatment and hardening heat treatment. The tensile testing bars were cast in accordance with the model designed by Gettleman and Harrison (1969) which was modified from the A. D. A. Specification No. 14 for dental chromium-cobalt casting alloy. Nine tensile test specimens were made from a split silicone mold for each of the test alloys to the size of 2.5mm in diameter and a gauge length of 10mm. All four alloys were handled in accordance with conventional methods used in Type III gold alloys. Ultimate tensile strength and elongation were measured on an Instron Universal Tensile Testing Machine (Model 1125, Japan) operated at a crosshead rate of 0.1cm/min. Elongation values were measured using Digital Measuring Microscope (MS-152, FUSOH, Japan). Vickers hardness was determined with a Vickers Hardness Tester (Model VKH-l, Japan) at a 1.0kg load on a mounted tensile test specimen. The following results were obtained from this study; 1. All tested alloys were composed of Au, Ag, Pd, Cu, Zn and Fe in common. The composition rate of gold for all four alloys was found in the range of $42{\sim}47$ weight % as shown below. Alloy A; Au 45%, Ag 40.2%, Pd 5.76%, others 9.04%. Alloy B; Au 47.1%, Ag 29.03%, Pd 6.98%, others 16.92%. Alloy C; Au 45%, .Ag 26.9%, Pd 6.83%, others 21.07%. Alloy D; Au 41.8%, Ag 34.4%, Pd 6.95%, others 16.85%. 3. The ultimate tensile strength of the four alloys was in the range of $31{\sim}82kg/mm^2$. The test results were shown in the below order from the highest value; As-cast condition; D, B, C, A. Softening heat treament; B, C, D, A. Hardening heat treatment; D, B, C, A. 4. The test :results of the elongation rate for each alloy were in the range of $0.5{\sim}18%$. The test results were shown in the below order from the highest value; As-cast condition; A, D, B, C. Softening heat treatment; A, C, D, B. Hardening heat treatment; C, D, B, A. 5. Vickers hardness for each of the four alloys was in the range of $120{\sim}230$. The test results were shown in the below order from the highest value; As-cast condition; C, B, D, A Softening heat treatment; D, B, C, A. Hardening heat treatment; D, A, C, B. 6. There were no differences in the physical properties between as-cast condition and softening heat treatment.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.394-405
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• 2009

Statement of problem: Crestal bone loss, a common problem associated with dental implant, has been attributed to excessive bone stresses. Design of implant's transgingival (TG) part may affect the crestal bone stresses. Purpose: To investigate if concavely designed geometry at a dental implant's TG part reduces peri-implant bone stresses. Material and methods: A total of five differently configured TG parts were compared. Base model was the ITI one piece implant (Straumann, Waldenburg, Switzerland) characterized by straight TG part. Other 4 experimental models, i.e. Model-1 to Model-4, were designed to have concave TG part. Finite element analyses were carried out using an axisymmetric assumption. A vertical load of 50 N or an oblique load of 50 N acting at $30^{\circ}$ with the implant's long axis was applied. For a systematic stress comparison, a total of 19 reference points were defined on nodal points around the implant. The peak crestal bone stress acting at the intersection of implant and crestal bone was estimated using regression analysis from the stress results obtained at 5 reference points defined along the mid plane of the crestal bone. Results: Base Model with straight configuration at the transgingival part created highest stresses on the crestal bone. Stress level was reduced when concavity was imposed. The greater the concavity and the closer the concavity to the crestal bone level, the less the crestal stresses. Conclusion: The transgingival part of dental implant affect the crestal bone stress. And that concavely designed one may be used to reduce bone stress.