• The Journal of Advanced Prosthodontics
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• 제3권2호
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• pp.69-75
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• 2011

This study assessed the effect of preparation design on marginal adaptation and also compared the sensitivity and specificity of clinical evaluation techniques for marginal accuracy of cast restorations to stereomicroscopy. MATERIALS AND METHODS. Three Ivorine molar teeth of different designs were prepared. (A)-A complete crown preparation with buccal shoulder and beveled finish line. (B)-A complete crown preparation with chamfer finish line. (C)-A three-quarter crown preparation with proximal boxes and beveled finish line. Twenty four castings were prepared with eight castings for each design respectively. Each casting underwent examination with an explorer, disclosing media, and a stereomicroscope. Stereomicroscopy at a value less than or equal to 30 microns was used as a gold standard to evaluate the significance of different designs on marginal adaptation. Chi-square tests of independence and Kruskal-Wallis were used to evaluate the effect of preparation design and compare the agreement between examination methods for detection of marginal gap size of greater than or equal to 30 microns (${\alpha}$=.05). Sensitivity and specificity for explorer and disclosing media as compared to stereomicroscope was calculated using statistical formula given by Park. RESULTS. The preparation design did not significantly affect overall marginal adaptation. Examination by explorer and disclosing media at $30 \;{mu}m$ revealed 39% and 10.06% sensitivity and 91% and 82% specificity respectively. CONCLUSION. Preparation designs examined in this study did not significantly affect the marginal adaptation of the castings. Commonly used clinical evaluation techniques using explorer and disclosing media appeared to be inadequate for assessment of marginal accuracy.

• 원예과학기술지
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• 제33권3호
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• pp.429-434
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• 2015

Apple blotch-like symptoms (ABLS) were observed on 'Fuji' apple leaves in Cheongsong, Gunwi and Yeongcheon apple orchards located in Gyeongbuk Province during 2010-2014. Characteristics of ABLS were yellowing, brown spots on leaves, and defoliation, similar to apple blotch diseased (ABD) leaves, which are infected with Marssonina coronaria. It is difficult to differentiate by eye between ABLS and ABD, which has led to misdiagnosis and overuse of fungicides. The present study was conducted to investigate the cause of ABLS using stereomicroscopy, culture isolation, cross-sectional analysis of leaves, and PCR. No acervuli were found on the surface of ABLS leaves and no growth was observed on potato dextrose agar (PDA) plates in culture. Furthermore, cross-sectional analysis revealed similar results, and mycelia were absent in ABLS leaves. By contrast, all these characteristics were present in ABD leaves. Furthermore, no fungi or viruses were detected in ABLS leaves by PCR, suggesting that the disease is not caused by these agents. These findings suggest that ABLS might be a physiological disorder in plants that is distinct from ABD.

• 한국산림과학회지
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• 제99권5호
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• pp.682-685
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• 2010

Coring has been widely used to measure annual increment in temperate forest ecosystems. This method is attractive because cores can be taken in just one visit. However, the accuracy of this method has not been tested. We expected coring to be less accurate than band dendrometers because of the eccentricity of tree growth. We studied 41 trees at the Long Term Experimental Forest in Mt. Gyebang, which has been monitored with band dendrometers since 1996. We collected two tree cores from the south and north face of each tree, 10 cm below the growth band. Increment cores were measured to 0.01 mm under stereomicroscopy. Annual growth from 1997 to 2006 was 3.2 mm $yr^{-1}$ for Quercus mongolica, 3.5 mm $yr^{-1}$ for Kalopanax septemlobus, and 5.7 mm $yr^{-1}$ for Pinus densiflora. The difference between the two methods was 10% for Q. mongolica, 14% for K. septemlobus, and 4% for P. densiflora. Compaction in the corer and shrinkage during drying decreased diameter increment by 5.6% and 1.0% on P. densiflora, respectively. This study suggests that the two methods for annual increment measurement are very similar, but species specificity should be concerned for direct comparison.

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.782-788
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• 2010

Microbiological calcium carbonate precipitation (MCP) has been investigated for its ability to improve the compressive strength of mortar. However, very few studies have been conducted on the use of calcite-forming bacteria (CFB) to improve compressive strength. In this study, we discovered new bacterial genera that are capable of improving the compressive strength of mortar. We isolated 4 CFB from 7 environmental concrete structures. Using sequence analysis of the 16S rRNA genes, the CFB could be partially identified as Sporosarcina soli KNUC401, Bacillus massiliensis KNUC402, Arthrobacter crystallopoietes KNUC403, and Lysinibacillus fusiformis KNUC404. Crystal aggregates were apparent in the bacterial colonies grown on an agar medium. Stereomicroscopy, scanning electron microscopy, and X-ray diffraction analyses illustrated both the crystal growth and the crystalline structure of the $CaCO_3$ crystals. We used the isolates to improve the compressive strength of cement-sand mortar cubes and found that KNUC403 offered the best improvement in compressive strength.

• Restorative Dentistry and Endodontics
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• 제42권4호
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• pp.290-300
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• 2017

Objectives: This study investigated the removal efficacy and cytotoxicity of a newly developed calcium hydroxide paste (cleaniCal, Maruchi) using N-2-methyl-pyrrolidone (NMP) as a vehicle in comparison with ApexCal (Ivoclar Vivadent) and Calcipex II (Nishika), which use different vehicles such as polyethylene glycol and propylene glycol, respectively. Materials and Methods: Thirty maxillary premolars with oval-shaped canals were divided into 3 groups and the teeth were filled with one of the pastes. After removal of the paste, micro-computed tomographic (${\mu}$-CT) imaging was obtained to assess the volume of residual paste in the root canal of each tooth. The teeth were then split longitudinally and the area of the paste-coated surface was evaluated by stereomicroscopy. The cytotoxicity of each product was assessed using an agar overlay assay. The effect of each vehicle on cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The data were analyzed using one-way analysis of variance and Tukey's tests to detect any significance (p < 0.05). Results: In the ${\mu}$-CT and stereomicroscopic analysis, cleaniCal exhibited less remnants of medicament than ApexCal and Calcipex. cleaniCal showed a higher cytotoxicity than the other pastes in the agar overlay assay. Furthermore, NMP exhibited lower cell viability compared to the other vehicles. Conclusions: cleaniCal showed better removal efficacy compared to the other products. However, clinicians should be aware of the higher cytotoxicity of the NMP-based material and consider its possible adverse effects on periradicular tissue when it is overfilled.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.43-50
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• 1984

이형흡충류의 하나인 Stellantchasmus falcatu에 의한 인체기생 2례가 praziquantel투약후 성충을 수집함으로써 화인되었다. 환자는 서울에 거주하는 24세 (제 1례) 및 55세 (제 2례) 남여로 제 1페는 설사, 복통 등 소화기증상과 불정맥(arrhythmia) 등 심식증상을 호소하면서 대편내에 광절렬류조충란이 양성이었고 제 2례는 소화불량과 조충류 편절 배출을 호소하였다. 조충감염 치료를 위해 praziquantel 15∼20mg/kg를 투여하고 MgSO4 30g으로 충체배출을 유도한 바 배출된 조충을 각각 확인하였다. 그러나 나머지 설사편을 입체해부현미경으로 세밀히 조사한 결과 제 1례에서는 188마리의 S. falcatus와 다른 3종의 이형흡충류가, 제 2례에서는 5마리의 S. falcatus가 수집되었다. 환자들은 숭어(Mugil cephalus) 등 반염수9을 회로 먹었다고 하며 이들이 감염원일 것으로 추측되었다.

• Parasites, Hosts and Diseases
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• 제22권1호
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• pp.37-42
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• 1984

이형흡충류의 하나인 Heterophyes heterophkes nocens에 의한 인체감염 2례가 치료후 충체를 얻세(제1예) 및 24세(제2예) 남자로 전남 고흥군 해안마을이 고향이거나 현재 거주지이며 제1예는 상복부 통증 및 소화불량 등의 증상을, 제2예는 EKG검사상 불정맥 및 ventricular premature be각 등 심장 기능이상과 설사, 복통 등 소화기 증상을 호소하였다. 1983연 4월 및 8월에 bithionol 30mg/kg 또는 prasiquantel 15mg/kg을 투여하고 설사편을 입체해부현미경하에서 검사한 바 각각 35및 67마리의 H. heterophyes noces가 수집되었다. 대편검사 또는 충체검사상 제 1예는 간흡충이, 제2예는 3종의 다른 이형흡충류와 광절렬두조충이 동시 감염되어 있었다. 환자들은 H. heterophyes nocens의 중간숙주인 숭어 (Mugil cephalus), 농어 (Lateolalabrax japonicus) 및 문절망둑(Acanthogobius navimanus) 등 반염수산 어류를 회로 먹은 정력이 있었다.

• 한국어류학회지
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• 제30권1호
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• pp.65-68
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• 2018

섬진자가사리 Liobagrus somjinensis 후각기관과 서식처 환경 및 생태적 습성의 연관성을 규명하기 위해 실체현미경과 디지털카메라를 이용하여 해부학적 특징을 묘사하였다. 후각기관은 주둥이 위에 좌우 한 쌍으로 존재하였으며, 전비공, 후비공, 비강으로 크게 구성되어 있었다. 전비공은 튜브형의 형태로 코수염과 윗입술 끝 사이에 위치하였다. 후비공은 표면과 평평한 유출공으로써 코수염의 기부 바로 아래에 위치해 있었다. 비강은 가로와 방사형으로 배열된 혀 모양의 22~24개의 판으로 구성된 로제트 구조를 보유하고 있었다. 결과적으로 섬진자가사리의 후각기관의 기능 해부학적 구조는 여울에서의 은신, 섭식, 야행성의 생활패턴에 연관된 높은 후각의존도를 반영하는 것으로 생각된다.

• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.165-170
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• 2014

PURPOSE. This study was aimed to evaluate effect of the desensitizing pretreatments on the micro-tensile bond strengths (${\mu}TBS$) to eroded dentin and sound dentin. MATERIALS AND METHODS. Forty-two extracted molars were prepared to form a flat dentin surface, and then they were divided into two groups. Group I was stored in distilled water while group II was subjected to a pH cycling. Each group was then subdivided into three subgroups according to desensitizing pretreatment used: a) pretreatment with desensitizer (Gluma); b) pretreatment with $CO_2$ Laser (Ultra Dream Pluse); c) without any pretreatment. All prepared surfaces were bonded with Single Bond 2 and built up with resin composite (Filtek Z250). The micro-tensile bond test was performed. Fracture modes were evaluated by stereomicroscopy. Pretreated surfaces and bonded interfaces were characterized by scanning electron microscope (SEM). The data obtained was analyzed by two-way ANOVA (${\alpha}$=0.05). RESULTS. For both sound and eroded dentin, samples treated with desensitizer showed the greatest ${\mu}TBS$, followed by samples without any treatment. And samples treated with $CO_2$ laser showed the lowest ${\mu}TBS$. SEM study indicated that teeth with eroded dentin appeared prone to debonding, as demonstrated by existence of large gaps between adhesive layers and dentin. CONCLUSION. Pretreatment with Gluma increased the ${\mu}TBS$ of Single Bond 2 for eroded and sound teeth. $CO_2$ laser irradiation weakened bond performance for sound teeth but had no effect on eroded teeth.

• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.