• 비파괴검사학회지
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• 제35권3호
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• pp.206-214
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• 2015

In this study, low-velocity impact damage (LVID) in glass fiber reinforced plastic (GFRP) was investigated using pulse thermography (PT) and lock-in thermography (LIT) techniques. The main objective of this study was to evaluate the detection performance of each technique for LVID in GFRP. Unidirectional and cross-ply GFRPs were prepared with four energy levels using a drop weight impact machine and they were inspected from the impact side, which may be common in actual service conditions. When the impacted side was used for both inspection and thermal loading, results showed that the suggested techniques were able to identify the LVID which is barely visible to the naked eye. However, they also include limitations that depend on the GFRP thickness at the location of the delamination produced by the lowest impact energy of five joule.

• Journal of the Optical Society of Korea
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• 제15권4호
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• pp.380-385
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• 2011

Common-path interferometers are widely used for endoscopic optical coherence tomography (OCT) because an arbitrary arm length can be chosen for the endoscopic imaging probe. However, the scheme suffers from the limited range of the sample position distance from the end of the imaging probe because the position between the reference reflector and the sample is limited by the optical path-length difference (OPD) to induce an interference signal. In this study, we developed a novel method for compensating the arbitrary sample position in common-path swept-source OCT by adding an extra Mach-Zehnder interferometer in the post-path of the interfered optical signal. Theoretical analysis and an experimental demonstration of imaging depth tuning for the flexible sample position of an endoscopic OCT image are discussed. After post-tuning of sample position distance, the positioning limitation between the reference reflector and the sample can be solved for various sample positions over a range of 26 mm for the cross-sectional images of a fish eye sample.

• 한국임상수의학회지
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• 제35권4호
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• pp.130-136
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• 2018

A 6-year-old spayed female American Cocker Spaniel presented with episcleritis in the right and then the left eye (OS) at eight month interval. Repeated intralesional triamcinolone acetonide was administered subconjunctivally to both eyes (OU). During this period, scleral ectasia was revealed on ocular funduscopy OS and then confirmed on ultrasonography and computed tomography. A year later, conjunctival hyperemia occurred around remnant triamcinolone particles and was treated by resection of these particles in the OU. A recurrence of episcleritis, which did not regress, required repeated triamcinolone subconjunctival injections four months later in the OU. Four months after these injections OU, the dog was presented with bilateral conjunctival mass, which had developed over the previous month. The round-shaped masses with diameters of 1 cm were surgically resected from exposed scleral ectasia lesion of thin and bulging scleral surface in the OU. The cross-section of both masses showed a white-colored accumulation at the center and triamcinolone induced granulomas enclosing necrotic tissue were confirmed by impression cytology and histopathological examination.

• Child Health Nursing Research
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• 제13권2호
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• pp.128-135
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• 2007

Purpose: To investigate health problems in child day care centers, needs for Child Care Health Programs, and management of sick children by day-care staff. Methods: A cross-sectional descriptive study. Day-care staff (N=206) from 33 day care centers in Seoul, completed a structured questionnaire. Results: Almost half of the day-care staff (53.4%) experienced sick events in their child at least once a month. The most frequently reported difficulty in having a sick child was in not having a health professional to consult, and almost all day-care staff (99.5%) had asked parents not to bring a sick child to the day care center. The biggest reason of exclusion was due to infectious disease including measles, chicken pox, mumps, diarrhea·vomiting, and pink eye. The majority of day-care staff (97.6%) agreed that there is a need for Center-based Child Care Health Program (CCCHP), and expected general health & illness management, and special care for chronic disease from CCCHP. Conclusion: These results showed a high incidence of sickness in children in day care centers, and there were great demands for a Center-based Child Care Health Program for day-care staff. Also the results of this study can be utilized as a basis for the establishment of child care policy in Korea.

• Molecules and Cells
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• 제26권4호
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• pp.329-337
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• 2008

Src-family kinases are critically involved in the control of cytoskeleton organization and in the generation of integrin-dependent signaling responses, inducing tyrosine phosphorylation of many signaling and cytoskeletal proteins. Activity of the Src family of tyrosine kinases is tightly controlled by inhibitory phosphorylation of a carboxy-terminal tyrosine residue, inducing an inactive conformation through binding with its SH2 domain. Dephosphorylation of C-ter tyrosine, as well as its deletion of substitution with phenylalanine in oncogenic Src kinases, leads to autophosphorylation at a tyrosine in the activation loop, thereby leading to enhanced Src activity. Beside this phophorylation/dephosphorylation circuitry, cysteine oxidation has been recently reported as a further mechanism of enzyme activation. Mounting evidence describes Src activation via its redox regulation as a key outcome in several circumstances, including growth factor and cytokines signaling, integrin-mediated cell adhesion and motility, membrane receptor cross-talk as well in cell transformation and tumor progression. Among the plethora of data involving Src kinase in physiological and pathophysiological processes, this review will give emphasis to the redox component of the regulation of this master kinase.

• 한국광학회지
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• 제22권3호
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• pp.122-128
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• 2011

하향신호를 위해서는 반사형 반도체 증폭기를 기반으로 한 광역선폭 광원 기술이 사용되었고 상향신호를 위해서는 파장 재사용 기술이 사용된 양방향 파장분할 다중화 수동 광네트워크 (WDM-PON)가 컴퓨터 시뮬레이션을 통해 구현되었다. 이 시스템에서 세가지 다른 종류의 광필터들이 비교되어 필터링의 영향이 분석되었고, 광 스펙트럼과 아이 다이어그램 (eye diagram)의 분석을 통해 파장 재변조 기술을 최적화 하였다. 최적화된 시스템 조건을 이용하여 양방향 신호의 전송 성능 곡선을 구하였고 이 시스템에서 반사에 의한 신호 왜곡의 영향을 분석하였다.

• 한국육종학회지
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• 제42권3호
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• pp.207-211
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• 2010

'Taedong Valley' is a high yielding and processing potato cultivar, which is a clonal selection resulting from a cross between 'W870' and 'A88431-1'. It is a medium maturating cultivar with medium plant height and light green foliage. 'Taedong Valley' has profuse flowering habit and light purple flowers. Tubers are smooth, round, and with yellow skin, light yellow flesh, medium eye depth. Tubers have medium dormancy and good keeping quality. 'Taedong Valley' has stable yield under wide range of climatic conditions. It is resistant to common scab and potato virus Y, but moderately susceptible to late blight. It is also resistant to most of the disorders, particularly dehiscence, hollow heart and internal brown spots. This cultivar has high level of tuber uniformity and capable of yielding 43.6 t/ha which is about 9.0% higher than the control potato cultivar 'Atlantic' under optimum agronomical practices.

• Toxicological Research
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• 제18권1호
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• pp.87-98
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• 2002

This study was conducted to evaluate the safety of a recombinant human Factor VIII(GC-$\gamma$ AHF) manufactured by Korea Green Cross Company with different technology according to the Regulation of Korean Food and Drug Administration (l 998. 12. 3). In acute toxicity test, both genders of Sprague-Dawley rats and Beagle dogs were administered intravenously with GC-$\gamma$ AHF of three doses (3,125, 625 and 125 IU/kg), and single dose of 3,125 IU/kg, respectively. No dead animal and abnormal autopsy findings were found in Control and GC-$\gamma$ AHF treated group. Therefore, the 50% lethal dose ($LD_{50}$) of GC-$\gamma$ AHF was conidered to be higher than 3,125 IU/kg in rats and dogs. In the four weeks repeated intravenous toxicity study, GC-$\gamma$ AHF was administrated intravenosly to both genders of rats and dogs with 3 doses (500, 150, 50 IU/kg). There were neither dead animals nor significant changes of body weights during the experimental Period. In addition, no significant GC-$\gamma$ AHF related changes were found in clinical sign, urinalysis and other finding. Statistically changes were observed in hematological, biochemical and organ weight parameters of treated groups: however these changes were not dose dependent. No histopathological lesion were observed in both control and treated animals. Above data suggest that no observed adverse effect level of test materials in rats and dogs might be over 500 IU/kg/day in this study. In ocular irritation test, any injury on iris, conjunctiva and cornea in rabbits were not observed. The acute ocular irritation index (A.O.I.), mean ocular irritation index (M.O.I.) and Day-7 individual ocular irritation Index (I.O.I.) of GC-$\gamma$ AHF were 0. In the primary skin Irritation test, the primary irritation index (P.I.I.) oj GC-$\gamma$ AHF were 0. Therefore, the GC-$\gamma$ AHF is considered not to have the primary skin and eye toxicity in rabbits. In active systemic anaphylaxis (ASA) test, GC-$\gamma$ AHF and GC-$\gamma$ AHF emulsified with Freund's complete adjuvant (FCA) did not induce any symptom of anaphylactic shock in guinea pigs. In passive cutaneous anaphylxis (PCA) test, after sensitization with antisera of GC-$\gamma$ AHF sensitized mice, blue spots were observed on the hypodermis of back of rats, but diameter of each spot was smaller than 5 mm in each test groups except the positive control group. Based on the results of this study, GC-$\gamma$ AHF is not conidered to have any antigenic potential. In conclusion, at levels of up to 500 IU/kg, GC-$\gamma$ AHF did not produce treatment-related toxicity under the conditions of these acute-, four week repeated-toxicity, primary skin and eye toxicity, and antigenicity test.

• Toxicological Research
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• 제21권1호
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• pp.15-21
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• 2005

There is now a growing concern about the possible toxicity of heavy metals in cosmetics. Heavy metals can be used as cosmetic ingredients or may be present as low level impurities in some of the raw materials. Chromium derivatives are used as pigments in cosmetics. Chromium is essential and toxic trace elements. Chromium may cause skin allergy. However, the regulations related to cosmetic products give no limit values for Chromium. Hexavalent chromium is significantly more toxic than trivalent chromium. Hexavalent chromium may present a carcinogenic risk at high concentrations. Therefore, it is important to consider oxidation state of chromium when analyze chromium. The purpose of this study is to determine the concentrations of water-soluble trivalent and hexavalent chromium in samples of makeup products, and to assess the safety of cosmetics on the basis of animal sensitization tests using guinea pig. The present study of chromium in 48 makeup products of 12 manufacturers provides a basis for assessing safety of makeup products. Water-soluble hexavalent chromium was not detected in any product. Water-soluble trivalent chromium was detected in only 9 eye shadows out of 48 makeup products, and could not be quantified 3 out of 9 eye shadows. The highest level of water-soluble trivalent chromium was about 10 mg/kg in spite of 90,000 mg/kg of total chromium. The results of animal sensitization tests show that 200 mg/kg of trivalent chromium and 5 mg/kg of hexavalent chromium have no harmful effect. No cross-reaction among these metals was found. Accordingly, the concentrations of water-soluble chromium in makeup products seemed to be safe. The overall results indicate that chromium in cosmetics probably have no significant toxicological effects. However, It is necessary to set guidelines on the maximum permissible concentration of water-soluble chromium in cosmetics.

• 한국가축번식학회지
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• 제25권4호
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• pp.295-304
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• 2001

양적형질 유전자 좌위 (QTL)의 탐색과 이들의 발현 양상 규명을 위해 Berkshire종과 Yorkshire종 간의 교배를 통해 생산된 F$_2$ 실험집단에서 regression interval mapping이 이루어졌다. 모두 525마리의 F$_2$ 자손들에서 일당 증체량, 평균 등지방 두께, 배장근 단면적이 표현형으로 조사되어 분석에 이용되었으며 모돈의 번식능력에 관련된 QTL 존재 여부 추정을 위해 간접 형질로 인정되고 있는 생시체중과 이유 시 체중을 분석에 포함하였다. 양적형질의 분리 여부를 추론하기 위하여 돼지의 2번 염색체에서 8종의 microsatellite 표지인자가 선택되어 유전자형이 조사되었다. 각각의 유전적 모델에서 산출된 통계량으로부터 QTL 존재 여부와 특정 QTL 발현 양상에 대한 여부를 나타낼 수 있는 인정되는 수준의 type I 오차율을 제어할 수 있는 임계값 (threshold)을 permutation test에 의해 제시하였다. QTL의 존재와 그 QTL의 Imprinting 여부는 부계와 모계를 통해 원가계 1세대의 대립유전자가 전달되는 과정에서 발현되는 특성을 분리시키는 통계적 의형을 설정하여 검정 통계량을 산출하였다. 분석에 이용된 3가지 형질과 연관된 3종류의 QTL 존재 가능성을 돼지의 2번 염색체에서 확인하였으며, 이들 중 평균 등지방 두께와 배장근 단면적에 각각 영향을 미칠 것으로 추론된 2종류의 QTL 발현은 정상적인 Mendelian 유전양식을 따르지 않고 imprinting된다는 증거를 얻어냈다. 또한 이들 imprinting되는 QTL은 이미 imprinting 표현 양식을 가진다고 알려진 IGF II 유전자의 위치와 거의 동일한 염색체강의 지점에서 부계로 전달되는 QTL만이 발현되는 특징을 보이는 것으로 밝혀졌다. 한편 Mendelian 모형과 imprinting 모형 모두에서 유의적인 임계값 이상을 보이는 검정 통계량이 산출된 일당 증체량 연관 QTL은 두 모형간의 적정성 분석을 위한 검정을 퐁해 Mendelian 양식을 따른 것으로 최종 확인되었다.