• 대한의생명과학회지
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• 제11권3호
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• pp.259-266
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• 2005

Mast cells and goblet cells have been known to protect the host against parasites. In this study, we examined the response of the mast cells and goblet cells over a period of 6 weeks in the duodenum, jejunum and ileum of C3H/HeN and C57BL/6 mice infected with Echinostoma hortense (E. hortense). In addition, we investigated whether the worm recovery rate of uninfected mice (the control group) or E. hortense-infected mice (the experimental group) was associated with the number of mast cells and goblet cells. The worm recovery rate was higher in the C3H/HeN mice than in the C57BL/6 mice. The number of goblet cells significantly increased in the experimental group of the C3H/HeN and C57BL/6 mice compared with the control group of both strains (P<0.005). Worm recovery peaked 3 weeks after the infection of the C57BL/6 mice and at 2 weeks after the infection of the C3H/HeN mice, and it was higher in the duodenum than in the jejunum and ileum. However, the infected site in the intestine had no relation with worm expulsion. In the C3H/HeN and C57BL/6 mice, the number of goblet cells in the experimental group was significantly higher than that in the control group (P<0.005). The number reached a peak 2 weeks after the infection and it even increased in duodenum, jejunum and ileum. The increased number of goblet cells was retained 6 weeks after infection. The number of goblet cells was higher in the C3H/HeN mice than in the C57BL/6 mice (P<0.01). These results indicate that goblet cells are related with the worm expulsion. Furthermore, immunohistostaining of the antral intestinal walls for lectin showed the significant increase of the number of goblet cells in the experimental group (P<0.001). The high infection rate in the duodenum was found during the early infection. An increased infection rate in the jejunum and ileum was found 3 weeks after infection and the infection rate was higher in the C3H/HeN mice than in the C57BL/6 mice. Taken together, the present study indicates that goblet cells, rather than mast cells, may play critical roles in parasite expulsion.

• Smart Structures and Systems
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• 제21권5호
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• pp.687-694
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• 2018

The problem of wheel tread defects has become a major challenge for the health management of high-speed rail as a wheel defect with small radius deviation may suffice to give rise to severe damage on both the train bogie components and the track structure when a train runs at high speeds. It is thus highly desirable to detect the defects soon after their occurrences and then conduct wheel turning for the defective wheelsets. Online wheel condition monitoring using wheel impact load detector (WILD) can be an effective solution, since it can assess the wheel condition and detect potential defects during train passage. This study aims to develop an FBG-based track-side wheel condition monitoring method for the detection of wheel tread defects. The track-side sensing system uses two FBG strain gauge arrays mounted on the rail foot, measuring the dynamic strains of the paired rails excited by passing wheelsets. Each FBG array has a length of about 3 m, slightly longer than the wheel circumference to ensure a full coverage for the detection of any potential defect on the tread. A defect detection algorithm is developed for using the online-monitored rail responses to identify the potential wheel tread defects. This algorithm consists of three steps: 1) strain data pre-processing by using a data smoothing technique to remove the trends; 2) diagnosis of novel responses by outlier analysis for the normalized data; and 3) local defect identification by a refined analysis on the novel responses extracted in Step 2. To verify the proposed method, a field test was conducted using a test train incorporating defective wheels. The train ran at different speeds on an instrumented track with the purpose of wheel condition monitoring. By using the proposed method to process the monitoring data, all the defects were identified and the results agreed well with those from the static inspection of the wheelsets in the depot. A comparison is also drawn for the detection accuracy under different running speeds of the test train, and the results show that the proposed method can achieve a satisfactory accuracy in wheel defect detection when the train runs at a speed higher than 30 kph. Some minor defects with a depth of 0.05 mm~0.06 mm are also successfully detected.

• 대한의생명과학회지
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• 제9권3호
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• pp.145-150
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• 2003

In the intestinal mucosa, mast cells are thought to be responsible for the expulsion of parasites. We investigated the relationship of worm expulsion and mast cells in C3H/HeN and BALB/c mice infected with Echinostoma hortense. In addition, we examined whether the worm recovery rate was associated with the strain of mice, and whether a toluidine stain and immunohistochemistry using the c-kit antibody was effective in the detection of mast cells. In order to investigate the mucosal immune response of C3H/HeN and BALB/c mice, each mouse was infected orally with 30 E. hortense metacercariae. Then, the number of mucosal mast cells and worm recovery rates was observed in experimentally infected mouse strains between 1 week and 8 weeks post infection (PI). Mucosal mast cells were increased in 3 weeks P.I. in C3H/HeN and BALB/c mice. On the other hand, only mucosal goblet cells and worm recovery rates correlated in C3H/HeN mice (P=0.0482). Worm recoveries in C3H/HeN mice were 65.7$\pm$5.6, 53.3$\pm$5.4 and 6.7$\pm$0.6 in week 1, 2, and 3 P.I. and strongly decreased in week 3 P.I. Worm recoveries in BALB/c mice were 23.0$\pm$2.5, 10.0$\pm$1.0, and 6.7$\pm$0.6% in week 1, 2, and 3 P.I. and gradually decreased from week 1 P.I. to week 3 P.I. Worm recoveries in C3H/HeN mice were significantly higher than in BALB/c mice (P<0.00l). The number of mast cells in C3H/HeN and BALB/c mice using the anti-c-kit antibody reached to a peak in week 3 P.I. and recovered as normal level in week 5 P.I. and 6 P.I. The number in E. hortense-infected C3H/HeN mice (P=0.0015) was higher than in E. hortense-infected BALB/c mice (P=0.01) compared with the control group. There were significant differences in the number of mast cells among regions of the intestine in in C3H/HeN mice (P<0.05) but not in BALB/c mice (P>0.05). Immunohistochemistry using the anti-c-kit antibody was significant method as an examination of the number of mast cells (P=0.0002). In conclusion, the present study demonstrated that mast cells play an important role in worm recovery, and immunohistochemistry using the anti-c-kit antibody was superior to toluidine stain as an examination of mast cells.

• 미생물학회지
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• 제17권4호
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• pp.165-178
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• 1979

Phages of Lactobaciilus casei (PLC) isolated from plant drainage were classified and characterized. The results are as follows : 1. On the basis of host range pattern, phages could be divided into 2 groups (PLC-B and PLC-C). PLC-B group phages could be further divided into 5 sub-groups $(B_1, \;B_2, \;B_3, \;B_4, \;and\;B_5)$. Although PLC-C group phages had the same host range, they could be also divided into 2 sub-groups $(C_1\;and\;C_2)$ by morphlogical type. 2. It was $B_3$ group phages that represented a major proportion (44.4%) of phages tested. However, $B_1$ group phages were shown to have the widest host range. 3. Electron micrographs revealed that the phages fell into three different morphological types. $(B_1, \;B_2, \;and\;B_3)$ group phages hd a hexagonal head (52nm in diameter) and a sheathless noncontractile (245 nm in length). $B_4\;and\;C_2$ group phages had a hexagonal head (56 nm) and a short flexible tail (169nm) having no sheath. $B_5\;and\;C_1$ group phages were shown to have a hexagonal head (81 nm) and a contractile tail (140 nm) having a sheath, a base plate and tail fibers. 4. The inactivation of the phages by antisera indicated that serological relationships correlated completely with morphological types. 5. $B_1, \;C_1\;and\;C_2$ group phages produced a large (1, 2 mm in diameter) plaque with a clear ring. The morphology of plaques of $B_3\;and\;B_5$ group phages was the same as those produced by the above, but the average plaque sizes for $B_3\;and\;B_5$ were 0.8 mm abd 0.5 mm, respectively. $B_2\;and\;B_4$ group phages produced a small (0.5 mm) turbid plaque with an irregular edge. 6. The latent period and the average burst size of $B_1\;and\;B_3$ group phages were 90 min and 100, respectively. These phages reuqired calcium ions for their miltiplication. 7. $B_3$ group phages could not be absrobed to R-variant $KC_1$. 8. The order of resistance of phages to heat was $B_2\;>\;B_1, B_4\;and\;B_5\;>\;B_3\;and\;C_2, \;B_5$ group phages were more stable than $B_3$ in various pH values. $C_2$ group phages were more sensitive to UV irradiation than $B_1\;and\;B_3$ group phages. 9. Strains YIT9018 and IAM 1043 were induced by mitomycin C treatment. Phage particles detected in the lysates had a hexagonal head (38 and 49 nm, respectively), but no tail. Any sensitive indicator strain could not be isolated in spite of repaeated trials.

• 식물병연구
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• 제13권2호
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• pp.110-114
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• 2007

콩나물 탄저병균 포자에 대한 열처리효과를 조사한 결과 $65^{\circ}C$에 30분까지 건열처리 하였을 때는 균의 사멸효과가 50% 정도에 불과하여, 건열처리는 나물콩 살균에 활용할 수 없었다. 병원균은 $55^{\circ}C$에서 20분 이상, 또는 $60^{\circ}C$에서 5분간 습열처리하면 완전히 사멸하였고, 부생성 세균 사멸효과도 높은 것으로 나타났다. $55^{\circ}C$에서 5분간 습열처리 조건하에서는, 발아장애 및 하배축 기형은 발생하지 않았으나, 20%의 탄저병균 분생포자가 생존하였기 때문에 실용적가치가 인정되지 않았다. 따라서 종자발아 및 하배축 기형이 발생하지 않는 최적 열처리 조건인 $60^{\circ}C$에서 5분간 습열처리를 실제 콩나물 재배 공정모델에 적용한 결과 탄저병 발생이 완전히 방제되어, 품질이 우수한 콩나물을 생산하게 되었다 따라서 이는 확립된 부패방지기술로서 적용이 가능하다고 판단되었다.

• 한국지반환경공학회 논문집
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• 제16권9호
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• pp.43-51
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• 2015

이 연구에서는 사실적인 매설관의 종방향 지진 응답특성을 규명하기 위하여 3차원 시간 이력해석이 가능한 쉘-스프링 수치모델을 구축하였으며 지진파 입사방향, 2방향 재하의 영향을 평가하였다. 조화운동을 적용한 결과, 이의 주기는 큰 영향을 주는 것으로 나타났다. 이는 주기가 감소할수록 매설관의 곡률이 증가하며 응답이 증가하기 때문인 것으로 판단된다. 입사방향의 영향을 평가하기 위하여 매설관 축 방향, 수평평면, 그리고 수직평면으로 운동을 재하 하였다. 매설관 축 방향으로 하중을 재하할 경우 휨 변형만을 유발하므로 응답이 매우 작게 계산되었다. 수평 및 수직평면에서 매설관 축 방향과 $45^{\circ}$로 재하 하는 경우 축방향 변위가 응답에 지배적인 영향을 주는 것으로 나타났다. 또한 2방향 재하 시, 휨 변형만을 유발하는 요소의 영향이 극히 작으므로 1방향으로만 재하 하는 경우와 결과가 유사하게 계산되었다. 계측기록을 재하 하는 경우에도 응답은 유사하게 계산되었고 1방향 및 2방향 해석의 결과는 크게 다르지 않은 것으로 나타났다. 결과적으로 매설관의 종방향 지진 응답은 축 방향 변위를 유발하는 1방향 재하만으로도 충분히 정확하게 예측할 수 있을 것으로 판단된다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.11-11
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• 2015

A total of sixty-six samples of Nuruk, a fermention starter used to make the Korean traditional rice wine, Makgeolli, were collected from central and southern regions of Korea in 2013 and 2014. We classified two groups of the Nuruk samples, "commercial" and "home-made", according to the manufacturing procedure and purpose of use. Commercial Nuruks were made in a controlled environment where the temperature and humidity are fixed and the final product is supplied to Makgeolli manufacturers. Home-made Nuruks were made under uncontrolled conditions in the naturally opened environment and were intended for use in the production of small amounts of home-brewed Makgeolli. We obtained more than five hundred isolates including filamentous fungi and yeasts from the Nuruk samples followed by identification of fungal species. Also we stored glycerol stocks of each single isolate at $-70^{\circ}C$. We identified the species of each isolate based on the sequences of ITS regions amplified with two different universal primer pairs. We also performed morphological characterization of the filamentous fungi and yeast species through observations under the microscope. We investigated the major fungal species of commercial and home-made Nuruks by counting the colony forming units (CFU) and analyzing the occurrence tendency of fungal species. While commercial Nuruks contained mostly high CFU of yeasts, home-made Nuruks showed relatively high occurrence of filamentous fungi. One of the representative Nuruk manufacturers used both domestic wheat bran and imported ones, mainly from US, as raw material. Depending on the source of ingredient, the fungal diversity was somewhat different. Another commercial Nuruk sample was collected twice, once in 2013 and again in 2014, and showed different diversity of fungal species in each year. Nuruks obtained from the southern regions of Korea and Jeju island showed high frequency of yeast such as Saccharomycopsis fibuligera and Pichia species as well as unique filamentous fungus, Monascus species. S. fibuligera was easily found in many Nuruk samples with high CFU. The major filamentous fungi were Aspergillus, Lichtheimia, Mucor and Penicillium species. In order to further our understanding of the isolates and their potential industrial applications, we assayed three enzymes, alpha amylase, glucoamylase and acid protease from 140 isolates out of about five hundred isolates and selected about 10 excellent strains with high enzyme activities. With these fungal isolates, we will perform omics analyses including genomics, transcriptomics, metabolic pathway analyses, and metabolomics followed by whole genome sequencing of unique isolates associated with the basic research of Nuruk and that also has applications in the Makgeolli making process.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.34-34
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• 2014

Filamentous fungi of the genus Colletotrichum (teleomorph, Glomerella) are considered major plant pathogens worldwide. Cereals, legumes, vegetables, and fruit trees may be seriously affected by this pathogen (1). Colletotrichum species cause typical disease symptoms known as anthracnoses, characterized by sunken necrotic tissue, where orange conidial masses are produced. Anthracnose appears in both developing and mature plant tissues (2). We investigated disease occurrence in apple orchards from 2013 to 2014 in northern Gyeongbuk province, Korea. Typical anthracnose with advanced symptoms was observed in all apple orchards studied. Of late, static fruit spot symptoms are being observed in apple orchards. A small lesion, which does not expand further and remains static until the harvesting season, is observed at the beginning of fruit growth period. In our study, static symptoms, together with the typical symptoms, were observed on apples. The isolated fungus was tested for pathogenicity on cv. 'Fuji apple' (fully ripe fruits, unripe fruits, and cross-section of fruits) by inoculating the fruits with a conidial suspension ($10^5$ conidia/ml). In apple inoculated with typical anthracnose fungus, the anthracnose symptoms progressed, and dark lesions with salmon-colored masses of conidia were observed on fruit, which were also soft and sunken. However, in apple inoculated with fungi causing static symptoms, the size of the spots did not increase. Interestingly, the shape and size of the conidia and the shape of the appressoria of both types of fungi were found to be similar. The conidia of the two types of fungi were straight and cylindrical, with an obtuse apex. The culture and morphological characteristics of the conidia were similar to those of C. gloeosporioides (5). The conidia of C. gloeosporioides germinate and form appressoria in response to chemical signals such as host surface wax and the fruitripening hormone ethylene (3). In this study, the spores started to germinate 4 h after incubation with an ethephon suspension. Then, the germ tubes began to swell, and subsequently, differentiation into appressoria with dark thick walls was completed by 8 h. In advanced symptoms, fungal spores of virtually all the appressoria formed primary hyphae within 16 h. However, in the static-symptom fungus spores, no primary hyphae formed by 16 h. The two types of isolates exhibited different growth rates on medium containing apple pectin, Na polypectate, or glucose as the sole carbon. Static-symptom fungi had a >10% reduction in growth (apple pectin, 14.9%; Na polypectate, 27.7%; glucose, 10.4%). The fungal isolates were also genetically characterized by sequencing. ITS regions of rDNA, chitin synthase 1 (CHS1), actin (ACT), and ${\beta}$-tubulin (${\beta}t$) were amplified from isolates using primer pairs ITS 1 and ITS 4 (4), CHS-79F and CHS-354R, ACT-512F and ACT-783R, and T1 and ${\beta}t2$ (5), respectively. The resulting sequences showed 100% identity with sequences of C. gloeosporioides at KC493156, and the sequence of the ${\beta}$t gene showed 100% identity with C. gloeosporioides at JX009557.1. Therefore, sequence data from the four loci studied proves that the isolated pathogen is C. gloeosporioides. We also performed random amplified polymorphic DNA-PCR, which showed clearly differentiated subgroups of C. gloeosporioides genotypes. The clustering of these groups was highly related to the symptom types of the individual strains.

• 생명과학회지
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• 제14권4호
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• pp.620-626
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• 2004

2001년부터 2003년까지 3년간 부산지역의 안과 병ㆍ의원으로부터 채취한 급성 바이러스성 결막염 환자의 가검물 675 건을 대상으로 유행한 눈병 원인 바이러스의 분리 결과, 유행성각결막염의 원인바이러스인 Adenovirus 8ㆍ37형, 급성 출혈성결막염(아폴로눈병)의 원인바이러스인 Coxsackievirus A24ㆍB3형, Echovirus 6ㆍ7형을 분리하였고 인두결막열을 일으키는 Adenovirus 3ㆍ4형을 분리하였으며 Coxsackievirus A24는 2002년 아폴로눈병의 대유행과 관련하여 2002 년 8월 국내 최초로 분리하였다. 2002년과 2003년에 분리된 Coxsackievirus B3와 Echovirus 6은 지금까지 뇌수막염을 유발시키는 원인바이러스로 널리 알려져 있으나, 눈병환자에서의 분리된 것은 특징적이었다. 월별 발생양상은 주로 하절기에 집중적으로 분포하였고, 2003년에는 4월과 10월에도 높은 발생율을 보였다. 연령별 발생분포도는 10대에서 50대까지 높은 발생율을 나타내었고 유아와 60대 이상에서도 발생하였고 남녀 발생비는 1.2ㆍ1이었다.

• 생명과학회지
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• 제23권3호
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• pp.406-414
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• 2013

강의 하류지역에서 미생물의 군집이 점진적인 염도의 증가에 따라 변한다는 것을 실험적으로 보기 위하여, 경북 형산강의 하류에서부터 연안해역으로 유입되는 곳까지 약 2.91 km 간격으로 0.02%, 1.48%, 2.63%, 3.62%의 염분을 포함하는 물 시료를 얻어 denaturing gradient gel electrophoresis (DGGE)를 수행하였다. 계통분석, 계통수 및 각 시료간의 연관성을 조사한 결과, 미생물 군집의 변화가 염분의 증가에 따라 점진적으로 변화하는 것을 확인하였으며, 이는 염분의 농도가 미생물 군집에 큰 영향을 미치는 요소임을 제시한다. 덧붙여 연안 지역이나 다른 수계환경에 비해 하류지역은 염분의 점진적인 변화로 인해 좁은 면적에 비하여 미생물 다양성이 크고, 이는 곧 특이하고 새로운 종을 찾기에 좋은 장소임을 시사하였다.