• 대한치과보철학회지
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• 제33권1호
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• pp.48-74
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• 1995

Since heat curing acrylic resins undergo unavoidable dimensional changes following polymerization, adaptation can be altered. Until recently, although numerous studies on the dimensional changes of denture base were based on a microscopic technic that measures the relative displacement of a limited reference points on the denture base, but there have been few studies on the distortions of resins using holographic interferometry. Purpose of this study was to determine and compare the dimensional changes and fringe patterns of 4 heat curing acrylic resins, and observe the distortions of acrylic resin denture base by temperature change with the aid of the holographic interferometry. Holographic interferograms were taken on the resin specimens and acrylic resin denture base with the 10mW He-Ne laser and double exposure method. Comparison and analysis of fringe pattern on the recorded object surface was performed. The following results were obtained. 1. The dimensional changes for the high impact resin Lucitone 199 were statistically the greatest of all resins, and the rapid heat curing resin Premium super 20 were the least. 2. The most polymerization shrinkage of all materials occured in initial period of measurements, at this time the difference of polymerization shrinkage properties between resins was founded. 3. The stress distribution of specimens was seen by various type of fringe pattern which had directionality. 4. The polymerization shrinkage of resins was greatly influenced by temperature change. 5. The partial deformations of resin denture base were observed in 70 C and 90 C water.

• Journal of Periodontal and Implant Science
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• 제40권2호
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• pp.49-55
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• 2010

Purpose: The purpose of this study was to preliminarily evaluate the influence of diabetes mellitus (DM) on periodontal tissue without establishment of periodontitis. Methods: Seven-week-old db/db mice were used for the diabetic experimental group and systematically healthy mice of the same age were used as controls. After 1 week of acclimatization, the animals were sacrificed for hard and soft tissue evaluation. The pattern of bone destruction was evaluated by stereomicroscope evaluation with alizarin red staining and radiographic evaluation by microscopic computerized tomography images. Histological evaluation was performed with hematoxylin and eosin stain for evaluation of soft tissue changes. Results: In both stereomicroscope evaluation and radiograph image analysis, aggressive form of bone destruction was observed in diabetic animals when compared to the systematically healthy controls. In histological evaluation, apical migration of junctional epithelium with slight inflammatory cell infiltration was observed with disarrangement of connective tissue fibers. Conclusions: Within the limits of this study, diabetic animals presented distortion in periodontal attachment and an aggressive bone loss pattern when compared to the healthy controls, suggesting that DM has an independent effect on periodontal tissue destruction irrespective of the presence or absence of periodontal disease.

• 수산해양교육연구
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• 제27권4호
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• pp.990-997
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• 2015

The condition factor (CF) were calculated by the morphometric data, and gonadal maturation and reproductive potential associated with fecundities of indoor cultured Hapalogenys nitens were investigated by microscopic and morphometric analysis from August 2011 to October 2012. Monthly changes in the GSI and CF were closely related to gonadal maturation and spawning. The ovary consisted of a pair of saccular structure with many ovarian lobules, the testis is a pair of lobular structure with many testicular lobules. The relationship between total fecundity (F) and total length (TL) of fish was expressed as $F=0.0449TL^{2.7926}$($r^2=0.0653$), and body weight (BW) was expressed as $F=1.4492BW^{0.8964}$($r^2=0.0863$). In this study, some exceptional special cases and phenomena were observed: absolute and relative fecundities were not increased with the increases of total length and body weight, respectively. Absolute and relative fecundities were no concerned with the increases of age classes of total length (cm) and of body weight (g).

• 한국ITS학회 논문지
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• 제16권6호
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• pp.42-52
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• 2017

본 연구는 대전광역시 중구에 위치한 대고오거리와 성모오거리를 대상으로 회전교차로 도입 시 나타나는 효과에 대하여 미시적 교통시뮬레이션 프로그램인 VISSIM을 이용하여 분석하였다. 분석결과 기존 교차로의 구간 별 평균 통행속도는 31.51km/h로 분석되었으며, 평균 지체시간은 32.5초로 분석되었다. 대고오거리만 회전교차로로 전환시 평균 통행속도 35.04km/h, 평균 지체시간 24.5초로 분석되었고, 성모오거리만 회전교차로로 전환될시 구간별 평균 통행속도는 34.79km/h, 지점별 평균 지체시간은 28.0초로 분석되었다. 마지막으로 대상지 2개 지점을 쌍구형 회전교차로로 전환 될 시의 구간 별 평균 통행속도는 38.62km/h, 지점별 평균 지체시간은 20.4초로 분석되었다. 이와 같이 두 개 교차로를 각각 회전교차로로 전환하는 시나리오에서 지체시간이 감소하는 것으로 나타났고, 두 개 지점을 모두 회전교차로로 연결하는 쌍구형 회전교차로 전환시 지체시간이 가장 적게 나타나 기존 교차로에 비해 효율적이라고 판단되었다.

• 한국컴퓨터정보학회논문지
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• 제18권6호
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• pp.101-110
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• 2013

베이비부머세대는 생애주기상 중년기에 해당한다. 이들은 안정된 고용과 소득기반을 상실한채 부모부양은 물론 자녀의 교육, 그리고 자신의 노후를 동시에 준비해야 하는 이중, 삼중의 경제적 부담을 안고 있다. 최근에 이들의 준비되지 않은 퇴직과 은퇴가 주요관심사이다. 본 연구는 베이비부머세대의 특성, 노후생애설계 교육에 대한 현황, 우리나라와 외국의 노후 생애설계 프로그램을 살펴보고 베이비부머세대의 노후생애설계교육 활성화방안을 탐색하고자 한다. 따라서 베이비부머 생애설계교육에서 노후생애설계에 대한 인식을 제고하고 구체적으로 어떻게 실현할 것인지에 대한 미시적 자료 분석을 중심으로 정책적, 실천적 대안을 모색하는 데 있다.

• 대한화학회지
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• 제21권1호
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• pp.53-59
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• 1977

알루민산나트륨과 알루민산칼륨 용액에 $CO_2$가스 吹入法에 의해 $NaAlCO_3(OH)_2\;(Dawsonite)와\;KAlCO_3(OH)_2$를 合成하였다. 이 反應은 80 ∼ $90^{\circ}C$에서 $Na_2O/Al_2O_3,\;K_2O/Al_2O_3$의 몰比가 各 各 6∼8, 8∼10인 알루민산알칼리 용액중에 $CO_2$가스를 吹?하여 達成되었다. 알루민산알칼리 용액중에 $HCO_3^-$이 多量 存在하며 알루미나가 平衡固相으로서 Boehmite로 存在할 때 高純度의 Dawsonate와 $KAlCO_3(OH)_2$가 生成된다는 것을 알았다. 이런 條件下에서 合成된 Dawsonite와 $KAlCO_3(OH)_2$의 示性式은 赤外線吸收스펙트럼 分析結果 各各 $NaAlO(OH)HCO_3와\;KAlO(OH)HCO_3$로 나타내는 것이 妥當하다고 생각된다. 또 電子顯微鏡觀察로부터 Dawsonite는 纖維狀結晶, $KAlCO_3(OH)_2$는 針狀結晶으로 되어 있다는 것을 알았다.

• Mycobiology
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• 제35권2호
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• pp.91-96
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• 2007

In the present study we first report in Korea the identification and characterization of Fusarium oxysporum isolated from rotten stems and roots of paprika (Capsicum annuum var. grossum) at Masan, Kyungsangnamdo in 2006. The fungal species produced white aerial mycelia accompanying with dark violet pigment on PDA. The optimal temperature and pH for the growth of the species was $25^{\circ}C$ and pH 7, respectively. Microscopic observation of one of isolates of the species shows that its conidiophores are unbranched and monophialides, its microconidia have oval-ellipsoidal shape with no septate and are of $3.0{\sim}11{\times}1.5{\sim}3.5\;{\mu}m$ sizes, its macroconidia are of $15{\sim}20{\times}2.0{\sim}3.5\;{\mu}m$ sizes and have slightly curved or slender shape with $2{\sim}3$ septate. The results of molecular analysis show that the ITS rDNA of F. oxysporum from paprika shares 100% sequence identity with that of known F. oxysporum isolates. The identified species proved it's pathogenicity by causing rotting symptom when it was inoculated on paprika fruits. The growth of F. oxysporum from paprika was suppressed on PDA by agrochemicals such as benomyl, tebuconazole and azoxystrobin. The identified species has the ability of producing extracelluar enzymes that degrade cellobiose and pectin.

• 미생물학회지
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• 제45권4호
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• pp.318-323
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• 2009

본 연구는 식중독 원인 세균인 Salmonella enteritidis JK-15를 장미추출물에 노출시켜 나타나는 살균효과를 조사하기 위하여 실시하였다. 분리세균인 S. enteritidis JK-15는 장시간 노출된 음식으로부터 농화, 분리되었다. 16S rRNA PCR을 수행하여 S. enteritidis JK-15의 유전학적 계통수를 작성하였다. BIOLOG 분석 시스템과 16S rRNA 염기서열 분석을 통하여 S. enteritidis 종(species)과 98% 유사성을 가졌으며, 이 균주를 S. enteritidis JK-15로 명명 하였다. 5~100 mg/ml 범위의 장미추출물에 노출된 S. enteritidis JK-15의 살균효과를 조사하였고, 100 mg/ml의 장미추출물에서 6시간, 그리고 50 mg/ml에서 12시간 이내에 완전히 살균되었다. 지수생장기의 S. enteritidis JK-15 균주는 노출된 장미추출물의 농도와 시간에 따라 lipopolysaccharide의 양이 변화하는 것을 SDS-PAGE와 silver staining을 통하여 관찰하였다. 또한, 주사전자현미경을 이용하여 장미추출물에 노출시킨 세균의 외부 형태를 분석한 결과, 움푹 패이고 불규칙적인 간균 형태로 관찰되었다.

• 한국지구과학회지
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• 제29권7호
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• pp.551-558
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• 2008

수왕광상은 중생대 백악기 중기의 반상화강암이나 선캄브리아기의 소백산 편마암 복합체에 발달한 열극을 충진한 석영맥에서 산출된다. 광물 공생군에 대한 연구 결과 광화작용은 4차례에 걸쳐 일어났다. 섬아연석은 광화작용이 진행되는 동안 광화 I, II, III기에 각각 정출하였다. 현미경 관찰과 전자현미분석 결과 섬아연석에서 나타나는 황동석 점적과 황동석 병변은 광화 III기 초에 열수용액의 교대작용에 의하여 생성되었을 것으로 생각된다. 황동석 병변의 생성과정은 아래와 같다. (1) Fe가 풍부한 용액이 Fe가 결핍된 섬아연석의 가장자리나 틈을 통해 Fe부화 (2)광화 II기에 Fe가 결핍된 섬아연석에 황동석 점적을 형성하고 Cu를 함유한 용액에 의해 황동석 점적 주변의 섬아연석에 Fe 감소 (3)광화 III기 초에 황동석 병변을 형성하였다.

• 한국수정란이식학회지
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• 제18권3호
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• pp.179-186
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• 2003

Human embryonic stem (hES) cell lines have been derived from human blastocysts and are expected to have far-reaching applications in regenerative medicine. The objective of this study is to improve freezing method with less cryo-injuries and best survival rates in hES cells by comparing various vitrification conditions. For the vitrifications, ES cells are exposed to the 4 different cryoprotectants, ethylene glycol (EG), 1,2-propanediol (PROH), EG with dime-thylsulfoxide (DMSO) and EG with PROH. We compared to types of vehicles, such as open pulled straw (OPS) or electron microscopic cooper grids (EM grids). Thawed hES cells were dipped into sequentially holding media with 0.2 M sucrose for 1 min, 0.1 M sucrose for 5 min and holding media for 5 min twice and plated onto a fresh feeder layer. Survival rates of vitrified hES cells were assessed by counting of undifferentiated colonies. It shows high survival rates of hES cells frozen with EG and DMSO (60.8％), or EG and PROH(65.8％) on EM grids better than those of OPS, compared to those frozen with EG alone (2.4％) or PROH alone (0％) alone. The hES cells vitrified with EM grid showed relatively constant colony forming efficiency and survival rates, compared to those of unverified hES cells. The vitrified hES cells retained the normal morphology, alkaline phosphates activity, and the expression of SSEA-3 and 4. Through RT-PCR analysis showed Oct-4 gene expression was down-regulated and embryonic germ layer markers were up-regulated in the vitrified hES cells during spontaneous differentiation. These results show that vitrification method by using EM grid supplemented with EG and PROH in hES cells may be most efficient at present to minimize cyto-toxicity and cellular damage derived by ice crystal formation and furthermore may be employed for clinical application.