• Korean Journal of Optics and Photonics
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• v.21 no.5
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• pp.214-223
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• 2010

Optimization of a 30 cm lightweight mirror was proposed with the best optical performance under various loads of gravity and thermal loads with proper boundary conditions. A pattern for a lightweight mirror was generated based on the best optical performance combined with ease of manufacturing for proper design parameters of physical properties of face sheet, back sheet, rib, and web. Evaluation of the optical performances of a telescope mirror was obtained by using the finite element analysis program, NX I-DEAS. Surface errors, individual aberration terms, such as piston, tilts, focus and other aberrations were calculated by using Zernike polynomials. The proposed telescope mirror meets well the opto-mechanical design consideration of RMS surface error less than 16 nm.

• Journal of Nutrition and Health
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• v.24 no.1
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• pp.1-11
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• 1991

In this study. the importance of body fat distribution as an indicator of metabolic aberrations in diabetics was'evaluated. Skinfold thicknesses at eight sites and circumferences at five sites and total body fat content were measured on 105 diabetics. 1) The waist/thigh girth ratio(WTR) was positively correlated(r=0.38-0.54) to plasma glucose levels during oral glucose loading in diabetic men alone. 2) There was no significant difference in serum total cholesterol of diabetics and nondiabetics. However, HDL-cholesterol was significantly lower(p : 0.000. in male and female) in diabetics(male : 36.31$\pm$ 16.98mg/dl, female: 37.89$\pm$14.67mg/dl) than nodiabetics(male 61.75$\pm$14.08mg/dl, female : 62.29$\pm$12.65mg/dl) and serum triglyceride was significantly higher(p=0.0212) in diabetic women(171.90$\pm$ 76.61mg/dl) than nondiabetic women(111.10$\pm$42.84mg/dl) . 3) In both sexes. anthropometric measurements that significantly correlated to serum triglyceride concentration were percentage of ideal body weight. body mass index(BMI) and waist circumference. Positive and significant correlations were found between serum cholestrol, and BMI(R: 0.31, 0.34) and waist circumference(r=0.29) in diabetic men. Moreover, skinfolds of trunk area(r=0.29~0.32) especially abdomen, were closely associated with serum lipids than other fat deposits. Increasing percentage of total body fat content was accompanied by progressively increasing serum triglyceride concentration(r=0.41) in dieabetic men. This study shows that knowledge of body fat localization may help identify risks of carbohydrate intolerance and hyperlipidemia in diabetics.

• Korean Journal of Clinical Laboratory Science
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• v.39 no.3
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• pp.151-155
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• 2007

Diagnosis and prevention of cytogenetics diseases are one of the most important parts in prenatal care. For that reason, it is necessary to examine birth defects. However, there is no reliable statistical data about birth defects in our country. In this study, the ratio of birth defects were determined by cytogenetics analysis and amniocentesis, in addition, the usefulness of amniocentesis was analyzed. The screening test and the triple marker test were conducted for 3,325 pregnant women of between 15 and 22 weeks gestation. Amniocentesis was performed for 170 pregnant women who were positive in the two tests, 184 women of advanced maternal age and 48 women with family history of chromosome aberrations. Among 419 women, 8 pregnant women who were positive in the triple marker test, 1 woman who close to the cut-off value in the triple marker test, 2 women with advanced maternal age and 1 woman who has history of chromosome aberration pregnance that was positive in cytogenetics analysis. The overall incidence of chromosomal aberration was 12 cases including 7 cases of Down's syndrome, 1 case of Patau syndrome, 1 case of Klinefelter syndrome, 1 case of Edward syndrome, 1 case of Robertsonian translocation and 1 case of XYY syndrome. These results show that amniocentesis for pregnant women who need chromosome test in prenatal cytogenetics analysis is very useful.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1305-1309
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• 2005

Experiments were conducted to determine the efficacy of modified montmorillonite nanocomposite (MMN) to reduce the toxic effects of aflatoxin (AF) in growing/finishing pigs. 96 weaned pigs were assigned to four dietary treatment groups (0 g of MMN and 0 mg of AF/kg feed, 3 g of MMN/kg feed, 0.1 mg of AF/kg feed, and 3 g of MMN plus 0.1 mg of AF/kg feed). Body weight gain (BW gain), feed/gain ratio, serum biochemical values and enzyme activities were evaluated. Compared with the control, AF alone markedly reduced BW gain and resulted in a significantly higher feed/gain ratio. There were no differences in BW gain and feed/gain ratio between 0.3% MMN or 0.3% MMN plus AF and the control. These results suggested that the deleterious effects of AF were ameliorated by MMN addition. AF intake markedly increased relative organ weights of liver, kidney, spleen and pancreas, and resulted in significant alterations of serum parameters. However, these parameters for pigs fed diets containing MMN and AF returned to normal values, indicating that MMN had the ability to recover the AF-decreased performance, organ damage and to correct aberrations in serum parameters. These findings in our study suggested that MMN can effectively modulate the toxicity of AF in growing/finishing pigs and may offer a novel approach to the preventive management of aflatoxicosis in animals.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.395-400
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• 2002

Recently, the increasing use of antenatal high resolutional ultrasonographic studies, and the increasing expertise of sonographers have contributed to the more frequent prenatal detecton of fetal hepatic calcification. Fetal hepatic calcification can arise from peritoneal, ischemic, infectious, neoplastic, and idiopathic causes. There are many reports that the prognosis is good in isolated fetal hepatic calcification without chromosomal aberrations, associated congenital malfomations or other organ abnormalities. We report one case of fetal hepatic calcification diagnosed by prenatal ultrasonography at gestational age of 27 weeks, without chromosomal abnormalities or other associated organ abnormalities, showing good prognosis.

• The Korean Journal of Zoology
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• v.32 no.3
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• pp.258-263
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• 1989

Nuclear Transplantation between Rana pipiens and Rana dybowskii When diploid blastula nuclei of Rana pipiens are traraplanted into enucleated eggs of Rana dybowskii the resulting nucleocytoplasmic hybrids are lethal-those development were arrested around the stage of the dorsal lip formation For the improvement of developmental capacity, serial nuclear transplantation was carried out. Even though serial transplantation of 15 generations showed normal development in each generation until gastrula stage, there was no sign of fundamental improvement in development afterward. This results implied that up to gastrulation normal DNA replication and cell division can take place in foreign cytoplasm. Since chromosomal aberrations both in shape and number were usually observed, the nuclei must have been modifted while resided in the foreign cytoplasm. Those nuclei didn't participate in normal development and led the embryos to early death. Tissue graft experiment indicated that the abnormal behavior of this lethal nucleocytoplasmic hybrid is an inherent property which is not corrected by the contact with its own tissue.

• Safety and Health at Work
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• v.2 no.1
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• pp.17-25
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• 2011

Objectives: In this study, the in vitro mammalian chromosomal aberration (CA) assay was conducted to gain additional information concerning the hazards associated with the use of cyclopentane and ammonium nitrate. While these two chemicals had already been tested by many methods, they had not been studied in the CA test. Methods: The assay was performed using the ovarian infantile cell (CHO-K1 cell), by the direct method (-S9) and by the metabolic activated method (+S9 mix). Results: Using the direct method, the 7 dosages in a 48 hour treatment group did not show that the frequency of CA is proportion to the dosage addition. The frequency of CA is not proportion to the dosage addition for a 6 hour treatment using the metabolic activated method. Conclusion: From these findings, it was decided that the 2 chemicals do not induce chromosomal aberrations under the tested conditions.

• Korean Journal of Optics and Photonics
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• v.8 no.2
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• pp.81-87
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• 1997

This paper presents the optimum initial design containing the first and third order properties of the four-group video camera zoom system using lens modules, and its real lens design. The optimum initial design with focal length range of 6.1693 to 58.4065 mm is derived by assigning appropriate first order quantities and third order aberrations to each module along with the specific constraints required for optimization. By scaling the focal length of each lens group, an initial real lens selected for each group has been designed to match its focal length into that of the each lens module, and then combined to establish an actual zoom system by adjusting the air space between the groups at all zoom positions. The combination of the separately designed groups results in a system which satisfies the first order properties of the zoom system consisting of original lens modules. As a result, by residual aberration correction, we could obtain a zoom system useful in video zoom camera employing the rear focus method.

• Korean Journal of Optics and Photonics
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• v.18 no.5
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• pp.337-344
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• 2007

In recent years, there has been rapid progress in different areas of vision science, such as refractive surgical procedures, contact lenses and spectacles, and near vision. This progress requires a highly accurate modeling of optical performance of the human eyes in different accommodation states. A new novel model-eye was designed using the Navarro accommodation-dependent finite model eye. For each of the vergence distances, ocular wavefront error, accommodative response, and visual acuity were calculated. Using the new model eye ocular wavefront error, accommodation dative response, and visual acuity are calculated for six vergence stimuli, -0.17D, 1D, 2D, 3D, 4D and -5D. Also, $3^{rd}\;and\;4^{th}$ order aberrations, modulation transfer function, and visual acuity of the accommodation-dependent model eye were analyzed. These results are well-matched to anatomical, biometric, and optical realities. Our corrected accommodation-dependent model-eye may provide a more accurate way to evaluate optical transfer functions and optical performances of the human eye.

• Korean Journal of Optics and Photonics
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• v.20 no.3
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• pp.148-155
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• 2009

In this paper, we analysed what effect the design variables, such as refractive index, central thickness and radius of curvature, had on the first order properties and image quality of optical systems when temperature changed. The optical parameters were varied at each temperature, then the coupling and ruler methods were used to design an athermalized lens for a phone camera. This concept was first used to design the lens for a 1/3.2" 5M phone camera. The designed lens satisfies all the specifications for a phone camera, and the variations of the back focal length(${\Delta}BFL$) are reduced to $10{\mu}m$ for a temperature range of $-10^{\circ}C$ to $+60^{\circ}C$. Also, the TTL of 5.5 mm results in a compact system. All design concepts and results discussed in this paper are expected to be useful in development for the phone and CCTV camera.