• Title/Summary/Keyword: aberrations

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Comparison of the Refracting Power and Aberration according to the Measurement Change in Illumination and Area of the Pupils (조도와 동공 영역의 측정 변화에 따른 굴절력과 수차의 비교)

  • Kim, Bong-Hwan;Han, Seon-Hee;Park, Byeong-Gyu;Hwang, Hyeon-Ju;Bae, Ye-Sol;Seo, Jeong-Bin;Yeo, Ye-Eun;Yoon, Min-Jeong;Kim, Hak-Jun
    • Journal of Korean Clinical Health Science
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    • v.4 no.2
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    • pp.550-555
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    • 2016
  • Purpose. We compared with the refracting power and aberration according to the measurement change in illumination and the pupils area by using the auto refraction instruments. Methods. In this study it were examined 64 eyes without eye disease, 21.4 (${\pm}2.54$) age, 32 (male 10, female 22) patients. Experiments in general illumination using the auto refraction instruments (HRK-8000A, Huvitz, Korea) was measured in both eyes 3 times and after scotopic for 30 minutes in a dark room blocked the light was measured in the same way. Aberration were measured coma, spherical aberration, high and low order aberrations in a general illumination (3500 lux) and low illumination (5 lux) of the pupil area 3.96 mm and 5.96 mm. Results. In the general illumination for measuring of the pupil area, the refractive power, coma, spherical aberration and low order aberration was no significant difference. In the low illumination, spherical aberration of the pupil area was $0.005({\pm}0.015){\mu}m$ in a 3.96mm, $0.014({\pm}0.020){\mu}m$ in a 5.96 mm and appeared a significant difference(p = 0.003). In general and low illumination on the results of comparing the measured values of the refractive power and aberration at the pupil area 3.96 mm, high order aberrations was $0.205({\pm}0.145){\mu}m$ in general illumination, $0.132({\pm}0.075){\mu}m$ in low illumination and appeared a significant differences(p = 0.001). High order aberrations at the pupil area 5.96 mm was $0.278({\pm}0.244){\mu}m$ in general illumination, $0.150({\pm}0.092){\mu}m$ in low illumination and appeared a significant differences(p = 0.000). Conclusions. When the eye refractive power measured by the automatic refraction does not depend on the illumination conditions and size of the observation pupil area, it was found that aberrations are affected by the illumination and the observation pupil area. It was found that the eye examination chamber illumination to obtain accurate measurement produces better results to decrease than to increase.

Effect of Radiotherapy on Chromosomal Aberration in Cancer Patients (암환자에서 방사선치료에의한 염색체이상)

  • Chun, Ha-Chung;Lee, Myung-Za;Yoo, Myung-Soo
    • Radiation Oncology Journal
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    • v.11 no.1
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    • pp.43-50
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    • 1993
  • We evaluated frequency and types of chromosomal aberrations by ionizing radiation in cancer patients treated with radiotherapy in our institution. Twenty-five patients with various types of carcinomas such as lung, uterine cervix, esophagus, rectum, head and neck and pancreatic cancers were studied immediately before and after external beam radiotherapy. The frequency of aberrant metaphase prior to treatment was $4.93{\%}$, which was higher than that of control group. Especially in lung cancer, the freuqency of aberrant metaphase was three times higher than control group. A comparison of chromosomal abnormalities observed before and after radiotherapy demonstrated that proportion of aberrant rnetaphases was significantly inreased to $22.13{\%}$. Major chromosomal aberrations like structural abnormalities showed remarkalbe increase from 65.45 to $88.45{\%}$ after the treatment. Also the numbers of chromosomal alterations per cell were increased by a factor of 6.5. Aberrations with two or more break points were more prominently increased, compared with aberrations with single break point. The number of chromosomal break points was noted to be higher than expected value in No.1, 3, 8 and 11 chromosomes and lower in No.13, 15, 17 and 21 chromosomes. Based on this study, we believe that the distribution of chromosomal breakage is related with gene and chromosomal rearrangement which could result in the development of cancers.

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Effects of Ara-C on UV and MMS-induced Excision Repair, Chromosome Aberrations, Sister Chromatid Exchanges and Replication Inhibition (자외선과 MMS에 의한 절제회복, 염색체이상, 자매염색분체 교환 및 복제억제 현상에 미치는 Ara-C의 영향)

  • Park, Kyung-Hee;Park, Sang-Dai
    • The Korean Journal of Zoology
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    • v.23 no.4
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    • pp.203-218
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    • 1980
  • Unscheduled DNA synthesis, chromosome aberrations, sister chromatid exchanges and DNA replication inhibition induced by the combined treatments with ara-C and UV-light or MMS in $HF_1$, CHO and $HelaS_3$ cells were studied, and the results obtained were as follows: (1) Ara-C was found to inhibit UV-or MMS-induced unscheduled DNA synthesis and the inhibitory effect of ara-C was more remarkable in its post-treatment. (2) Ara-C enhanced the rate of chromosome aberrations induced by MMS or UV-light. Post-treatment with ara-C exhibited the synergistic effect on MMS-induced chromosome aberrations mainly by increases of chromatid deletions. (3) Contrarily, ara-C did not increase the rate of sister chromatid exchanges, particularly in the pre-treatment with MMS, although it was found to induce sister chromatid exchanges. (4) The rate of DNA synthesis was declined immediately after are-C treatment and then recovered. The combined treatments with ara-C and UV-light or MMS showed that the initial response on replication inhibition was similar to that of ara-C, but later responses were similar to that of UV-light or MMS treated group.

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Studies on the Effects of Steroids on DNA Synthesis of Chromosmoes in Synchronized Human Cells (同時分裂促進된 사람의 培養細胞에 있어서 染色體의 DNA 合成에 미치는 Steroids의 영향)

  • Kang, Yung Sun;Park, Sang Dai;Ryu, Chung Hee
    • The Korean Journal of Zoology
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    • v.12 no.3
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    • pp.85-93
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    • 1969
  • The frequencies of chromosomal aberrations, unmerical variations at various time intervals and DNA synthetic patterns after the treatment with steroids in synchronized human kidney cells treated with 5-AU were investigated in the present experiment. 1. In 5-AU treated group, the frequency of chromosomal aberrations per cell was 0.131, 3 times of control group. In 5-AU + progesterone and 5-AU + testosterone groups, the frequency of chromosomal aberrations per cell was 0.340 and 0.452 respectively. 2. In 5-AU treated group, the frequency of cells with abnormal chromosome number was 0.8%, which was distributed throughout the time regardless of time interval. In 5-AU + progesterone and 5-AU + testosterone groups, the frequencies of cells with abnormal chromosome number were 2.2% and 4.3% respectively and they increased with the time. In 5-AU + progesterone group, the frequency of chromosomal aberrations exhiited the peaks at 12 and 18 hour stage after the treatment with steroids and, in 5-AU + testosterone group, it decreased with the time and in 5-AU treated group no significant difference was observed 3. The increase of labeled metaphases and labelling intensities in 5-AU treated cells are the result of the accumulation of cells at S stage by 5-AU. The decrease of labeled metaphases, labelling intensities and the delay of DNA synthetic time were observed in steroid groups. DNA synthetic pattern of sex chromosomes differs according to the step of cell cycle and DNA synthetic time is irregular because of double treatments with 5-AU and steroids.

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Simulation of Lens Aberration Correction for Polygon Mirror Scanning (PMS) (Polygon Mirror Scanning (OMS)을 위한 렌즈의 구면 수차 보정 시뮬레이션)

  • 신승연
    • Proceedings of the Optical Society of Korea Conference
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    • 1999.08a
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    • pp.128-129
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    • 1999
  • Polygon Mirror Scanning(PMS) is composed of LED array, magnifying lens, polygon mirror and motor. It is important to correct the lens aberrations to gain the image we want to show. In this paper, we have simulated the lens aberration correction to reduce the spherical aberration . We have obtained a aspherical lens which is corrected the spherical aberration.

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A Cytogenetic Study in Patients Referred for Suspected Chromosomal Abnormalities (염색체 이상 환자의 세포 유전학적 연구)

  • Oh, S.K.;Lee, H.H.;Moon, S.Y.;Chang, Y.S.
    • Clinical and Experimental Reproductive Medicine
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    • v.12 no.2
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    • pp.39-57
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    • 1985
  • Presented in this paper the data from a chromosome study of 397 patients referred for suspected chromosmal abnormalities. Karyotypes were obtained using short-term blood culture and direct method. Of these 238 patients had normal chromosome complements; 159 (40.1%) patients had chromosome abnormality. Among all patients with chromosome abnormalities, 82.4% (131/159) had aberrations of chromosome number, the others 17.60/0 (28/159\ had aberrations of chromosome structure. Ten had a chromosome rearrangement; Five of them were reciprocal and five Robertsonian translocations. Four patients with pericentric inversions and one with paracentric inversions and four with isochromosomes were observed. There were four patients with marker chromosome, two patients had a chromosome insertion; and three others. (additional abnormal chromosomes.) Thus the results of the present study indicate the importance of cytogenetic evaluation in clinically abnormal patients.

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Genetic Toxicity Study of YH1715 Series, Antifungal Agents (YH1715계열 항진균제의 유전독성평가)

  • 하광원;오혜영;박장환;허옥순;손수정;한의식;이종영;김소희;강희일
    • Environmental Mutagens and Carcinogens
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    • v.18 no.2
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    • pp.93-97
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    • 1998
  • The results of chromosome aberration test in mammalian cells in culture (Chinese hamster lung fibroblast cells) showed no induction of structural and numerical aberrations by antifungal agents of YH1715 series regardless of metabolic activation. While positive control group (mitomycin C and benzo(a)pyrene) showed structural chromosome aberrations of 37% and 23%, respectively. The in vivo induction of micronuclei was measured in polychromatic erythrocytes in bone marrow of male ddY mouse given YH1715R and YH1729R at 1, 0.5, 0.25 g/kg by p.o. once. After 24 hours, animals were sacrificed and evaluated 40 the incidence of micronucleated polychromatic erythrocytes in whole erythrocytes. Although a positive response for induction of micronuclei in animals treated with mitomycin C demonstrated the sensitivity of the test system for detection of a chemical clastogen, YH1715R did not induce micronuclei in bone marrow of ddY male mice but induced cytotoxicity to bone marrow cells at the highest concentration (1 g/kg, p〈0.05), and YH1729R induced micronuclei in bone marrow of ddY male mice dose dependently (p<0.05) but did not induce cytotoxicity to bone marrow cells.

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Optical design of three-mirror telescope system for infra-red and visible imaging (적외선 및 가시광선 결상용 3반사망원경계의 설계)

  • 이종웅;홍경희;권우근
    • Korean Journal of Optics and Photonics
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    • v.7 no.3
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    • pp.183-190
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    • 1996
  • To design three-mirror telescope system (F/8, 120 inch in focal length) for visible and infra-red band imaging, methods for power configuring and correction of the third order aberrations were studied. In the design of the telescope system, a three-mirror system corrected for spherical aberration, coma, and astigmatism was used for infra-red imaging, and the aberrations were corrected by using conic surfaces. For visible imaging, a singlet corrector lens was appended at the front of the focal plane to correct filed curvature. The telescope system has diffraction limited performance for 10 ${\mu}{\textrm}{m}$ in wavelength within 2.4$^{\circ}$ of field-of-view. In the visible band imaging, the rms spot size of the telescope system is less than 25 ${\mu}{\textrm}{m}$ within 3$^{\circ}$ of field-of-view for monochromatic light, and the telescope system satisfies flat field condition for CCD application.

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