• Journal of Microbiology
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• 제44권1호
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• pp.106-112
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• 2006

In this study, the genetic diversities of multi-resistant Salmonella typhimurium (ST) isolates were analyzed via the application of both pulsed field gel electrophoresis (PFGE) and Polymerase chain reaction (PCR) analysis methods, using 6 kinds of primers (REP, ERIC, SERE, BOX, P-1254 and OPB-17). And their discriminative abilities (DA) were also compared in order to determine the most effective and reliable analysis method. 118 S. typhimurium isolates, cultured from diverse animals and human patients in Korea beginning in 1993, were analyzed and subjected to a comparison of Simpson's index of diversity (SID), using both PFGE and PCR methods. PFGE by XbaI enzyme digestion allowed for discrimination into 9 pulsotypes, with high SID values (0.991) on the genomic DNA level. This shows that PFGE is a very discriminative genotypic tool, and also that multiple clones of S. typhimurium isolates had existed in domestic animals and humans in Korea since 1993. However, we could ultimately not to trace the definitive sources or animal reservoirs of specific S. typhimurium isolates examined in this study. Depending on the SID values, the combined method (7 kinds of method) was found to be the most discriminative method, followed by (in order) SERE-PCR, REP-PCR, ERIC-PCR, PFGE & OPB-17 (RAPD), P-1254 (RAPD), and BOX-PCR at the $80\%$ clone cut-off value. This finding suggests that the REP-PCR method (which utilizes 4 primer types) may be an alternative tool to PFGE for the genotyping of S. typhimurium isolates, with comparable cost, time, and labor requirement. The establishment of a highly reliable and discriminatory method for epidemiologic analysis is considered necessary in order for researchers to trace the sources of specific pathogens and, consequently, to control and prevent the spread of epidemic S. typhimurium isolates to humans.

• 한국잡초학회지
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• 제16권4호
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• pp.259-263
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• 1996

1. 충남지역 시설채소재배지에서 발생한 잡초는 약 30여종이었으며 구슬갓냉이, 둑새풀, 별꽃, 쇠비름, 바랭이, 명아주 등이 전반적으로 우점도가 높은 것으로 나타났다. 2. 충남지역의 서북부 해안지역에서는 별꽃, 쇠비름, 둑새풀, 서남부 해안지역에서는 구슬갓냉이, 바랭이, 별꽃, 내륙북부지역에서는 구슬갓냉이, 둑새풀. 바랭이, 내륙남부지역에서는 구슬갓냉이, 둑새풀, 쇠비름 순으로 높은 우점도를 나타냈다. 3. 충남지역의 배추포장에서는 별꽃, 구슬갓냉이, 쇠비름, 무포장에서는 구슬갓냉이, 털비름, 별꽃 등, 오이포장에서는 털비름, 별꽃, 바랭이 등, 파포장에서는 구슬갓냉이, 쇠비름 등이 높은 우점도를 나다냈다.

• Mycobiology
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• 제45권4호
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• pp.401-408
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• 2017

Colletotrichum gloeosporioides is an economically important fungal pathogen causing substantial yield losses indifferent host plants. To understand the genetic diversity and molecular epidemiology of this fungus, we have developed a novel, high-resolution multi-locus microsatellite typing (MLMT) method. Bioinformatic analysis of C. gloeosporioides unannotated genome sequence yielded eight potential microsatellite loci, of which five, CG1 $(GT)_n$, CG2 $(GT1)_n$, CG3 $(TC)_n$, CG4 $(CT)_n$, and CG5 $(CT1)_n$ were selected for further study based on their universal amplification potential, reproducibility, and repeat number polymorphism. The selected microsatellites were used to analyze 31 strains of C. gloeosporioides isolated from 20 different host plants from India. All microsatellite loci were found to be polymorphic, and the approximate fragment sizes of microsatellite loci CG1, CG2, CG3, CG4, and CG5 were in ranges of 213-241, 197-227, 231-265, 209-275, and 132-188, respectively. Among the 31 isolates, 55 different genotypes were identified. The Simpson's index of diversity (D) values for the individual locus ranged from 0.79 to 0.92, with the D value of all combined five microsatellite loci being 0.99. Microsatellite data analysis revealed that isolates from Ocimum sanctum, Capsicum annuum (chili pepper), and Mangifera indica (mango) formed distinct clusters, therefore exhibited some level of correlation between certain genotypes and host. The developed MLMT method would be a powerful tool for studying the genetic diversity and any possible genotype-host correlation in C. gloeosporioides.

• Journal of Forest and Environmental Science
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• 제35권3호
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• pp.159-172
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• 2019

Madhupur National Park (MNP) is one of the last remaining patches of old-growth natural Sal forest left in Bangladesh where the forest is tropical moist deciduous type. A study was revealed to assess the tree species diversity and composition in this area. For determining tree species the study was conducted through extensive random quadrat survey methods with $20m{\times}20m$ sized plots. Results of the study indicated that there were 139 tree species belonging to 100 genera and 40 families. The quadrat survey assessed the basal area, stem density, diversity indices and importance value index of the tree species having ${\geq}5cm$ D.B.H (Diameter at Brest Height). The basal area and stem density of the tree species were $20.689{\pm}1.08m^2/ha$ and $1412.93{\pm}64.27stem\;ha^{-1}$ while, diversity indices, i.e. Shannon-Wiener's diversity, Simpson's evenness, Margalef's species richness and Pielou's dominance indices indicated poor diversity in comparison to that of other PAs (Protected Areas) in South-Eastern region of Bangladesh. The structural composition based on height and D.B.H through reverse-J shaped curve indicated higher regeneration and recruitment but removal of trees of large growth classes. Sal (Shorea robusta) was the most dominant tree species that accounts 75% of the total tree individuals in the natural forest patches. However, some associates of Sal, i.e. Bhutum (Hymenodictyon orixensis), Gadila (Careya arborea), and Kusum (Schleichera oleosa) etc. were seemed to be rare in MNP.

• Safety and Health at Work
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• 제10권3호
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• pp.321-326
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• 2019

Background: Performing cognitive tasks and muscular fatigue have been shown to increase muscle activity of the lower extremity during quiet standing. A common intervention to reduce muscular fatigue is to provide a softer shoe-surface interface. However, little is known regarding how muscle activity is affected by softer shoe-surface interfaces during static standing. The purpose of this study was to assess lower extremity muscular activity during erect standing on three different standing surfaces, before and after an acute workload and during cognitive tasks. Methods: Surface electromyography was collected on ankle dorsiflexors and plantarflexors, and knee flexors and extensors of fifteen male participants. Dependent electromyography variables of mean, peak, root mean square, and cocontraction index were calculated and analyzed with a $2{\times}2{\times}3$ within-subject repeated measures analysis of variance. Results: Pre-workload muscle activity did not differ between surfaces and cognitive task conditions. However, greater muscle activity during post-workload balance assessment was found, specifically during the cognitive task. Cognitive task errors did not differ between surface and workload. Conclusions: The cognitive task after workload increased lower extremity muscular activity compared to quite standing, irrespective of the surface condition, suggesting an increased demand was placed on the postural control system as the result of both fatigue and cognitive task.

• The Plant Pathology Journal
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• 제37권6호
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• pp.521-532
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• 2021

Knowledge and better understanding of functions of the microbial community are pivotal for crop management. This study was conducted to study bacterial structures including Acidovorax species community structures and diversity from the watermelon cultivated soils in different regions of South Korea. In this study, soil samples were collected from watermelon cultivation areas from various places of South Korea and microbiome analysis was performed to analyze bacterial communities including Acidovorax species community. Next generation sequencing (NGS) was performed by extracting genomic DNA from 92 soil samples from 8 different provinces using a fast genomic DNA extraction kit. NGS data analysis results revealed that, total, 39,367 operational taxonomic unit (OTU), were obtained. NGS data results revealed that, most dominant phylum in all the soil samples was Proteobacteria (37.3%). In addition, most abundant genus was Acidobacterium (1.8%) in all the samples. In order to analyze species diversity among the collected soil samples, OTUs, community diversity, and Shannon index were measured. Shannon (9.297) and inverse Simpson (0.996) were found to have the highest diversity scores in the greenhouse soil sample of Gyeonggi-do province (GG4). Results from NGS sequencing suggest that, most of the soil samples consists of similar trend of bacterial community and diversity. Environmental factors play a key role in shaping the bacterial community and diversity. In order to address this statement, further correlation analysis between soil physical and chemical parameters with dominant bacterial community will be carried out to observe their interactions.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.487-487
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• 2023

농업 분야에서 미생물은 영양분 가용화, 유기물 분해 등 토양 영양분 공급에 중요한 역할을 하며, 토양 건강성 증진, 식량 안보 및 식품 건강 면에서 많은 활용 가능성을 지니고 있다. 최근 유역 환경 건강성, 생물 다양성 보존, 효율적인 고품질 농산물 생산에 대한 관심이 커져, 지속 가능한 농업 중 하나인 유기농업과 관행농업 토양의 이화학적 및 생물학적 특성에 관한 비교 연구가 진행되고 있다. 미생물은 지속 가능한 농업 발전의 중요한 요소 중 하나로써, 미생물 다양성이 풍부할수록 토양 비옥도, 작물 성장 면에서 긍정적인 영향을 미친다고 알려져 있다. 본 연구는 이에 대한 기초 데이터를 제공하기 위해 논 경작지를 대상으로 유기 및 관행농업 토양의 미생물 군집조성과 Alpha diversity analysis(Chao1, Shannon, Simpson index)을 통해 비교하였다. 경기도 양평군에서 유기 및 관행 논 지역을 각각 1지점씩 선정하였으며, 8월부터 11월까지 총 4회 현장 조사를 진행하였다. 미생물 분석은 차세대염기서열분석을 실시하였으며, bacteria는 16S rRNA V3-4 영역, fungi는 ITS 3-4 영역을 sequencing 하였다. 미생물 군집조성은 문수준에서는 큰 차이가 없었으나, 속수준에서는 fungi 군집조성에 차이를 보였다. 예로 Ustilaginoidea 속은 관행 논 토양에서만 발견되었으며, 벼 이삭누룩병을 일으키는 병원균으로 과도한 질소 비료 시비가 원인으로 추정된다. 종 다양성은 bacteria diversity의 경우 관행 논 토양에서 높게 측정되는 반면, fungi diversity의 경우 유기 논 토양에서 높게 측정되었다. 결론적으로 체계적인 시비 관리 통해 미생물 군집은 조절될 수 있으며, 관행농업은 적절한 시비를 통해 토양 건강성 및 식품 건강성 면에서 유기농업과 비슷한 효과를 보여줄 가능성이 있다고 판단된다.

• Tuberculosis and Respiratory Diseases
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• 제86권4호
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• pp.294-303
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• 2023

Background: The human lung serves as a niche for a unique and dynamic bacterial community related to the development and aggravation of multiple respiratory diseases. Therefore, identifying the microbiome status is crucial to maintaining the microecological balance and maximizing the therapeutic effect on lung diseases. Therefore, we investigated the histological type-based differences in the lung microbiomes of patients with lung cancer. Methods: We performed 16S rRNA sequencing to evaluate the respiratory tract microbiome present in bronchoalveolar lavage fluid. Patients with non-small cell lung cancer were stratified based on two main subtypes of lung cancer: adenocarcinoma and squamous cell carcinoma (SqCC). Results: Among the 84 patients analyzed, 64 (76.2%) had adenocarcinoma, and 20 (23.8%) had SqCC. The α- and β-diversities showed significant differences between the two groups (p=0.004 for Chao1, p=0.001 for Simpson index, and p=0.011 for PERMANOVA). Actinomyces graevenitzii was dominant in the SqCC group (linear discriminant analysis [LDA] score, 2.46); the populations of Haemophilus parainfluenza (LDA score, 4.08), Neisseria subflava (LDA score, 4.07), Porphyromonas endodontalis (LDA score, 3.88), and Fusobacterium nucleatum (LDA score, 3.72) were significantly higher in the adenocarcinoma group. Conclusion: Microbiome diversity is crucial for maintaining homeostasis in the lung environment, and dysbiosis may be related to the development and prognosis of lung cancer. The mortality rate was high, and the microbiome was not diverse in SqCC. Further large-scale studies are required to investigate the role of the microbiome in the development of different lung cancer types.

• 한국농림기상학회지
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• 제5권3호
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• pp.151-157
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• 2003

본 연구는 경기도 가평과 충청북도 영동에 조성된 풍매차대검정림의 하층식생에 대한 입지환경에 따른 군락조성 및 구조에 대한 변화와 특성을 구명하고자 수행되었다. 가평지역의 임분내 경사는 영동지역에 비해 완만했으며, 토양의 화학적 성질을 분석한 결과 가평지역이 전반적으로 영동치역 보다 전체적인 함량 비율이 낮은 것으로 나타났다. 임분내 지역별 임상에 도달하는 상대광도는 가평지역보다 영동치역이 매우 높았다. 전반적으로 잣나무의 생장은 가평지역이 영동지역에 비하여 현저히 우수한 생장상태를 보이고 있다. 잣나무 임분의 지역별 관목층의 종구성과 상대 밀도, 빈도, 피도 및 중요치 등에 대한 분석 결과, 가평지역은 신갈나무와 상수리나무가 우점종으로 나타났으며 영동지역은 상수리나무가 우점종으로 나타났다. 하층식생은 가평지역에 출현하는 종들은 대부분 토양이 습윤하며 음지에 볼 수 있는 종들로 구성되어 있다. 영동지역은 가평지역에 비해 적은 종이 출현하며 대부분 경사가 심하고 토양이 건조하며 햇빛이 많이 도달하는 곳에 출현하는 종들로 특히 산딸기가 우점종으로 나타났다. 지역별 잣나무임분의 관목층 및 하층식생의 전체 종다양도는 가평지역이 영동지역보다 높았다. 이러한 결과는 두 지역간의 지형적인 특성인 경사도의 상이한 차이로 판단되며, 가평지역은 잣나무 생장을 고려하여 간벌이 시행되어져야 하며, 영동은 하층식생에 대한 무육관리가 시급한 것으로 사료된다.

• Journal of Plant Biology
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• 제28권2호
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• pp.165-175
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• 1985

지리산 피아골의 식생은 식물사회학적 방법에 의해 개서나무군낙, 서나무군낙, 신갈나무군낙, 졸참나무군낙, 들메나무군낙, 철쭉-진달래 관목림으로 분류되며, DBH-class 분포에 의하면 개서나무군낙, 서나무군낙, 신갈나무군낙은 모두 안정된 극상림인 것으로 보인다. 신갈나무군낙의 종다양도는 제일 낮고 우점도는 제일 높게 나타났으며, 토양조건은 서나무군낙이 신간나무군낙에 비해 습하고 비옥한 것으로 나타났다. 서나무군낙과 신갈나무군낙의 점이대는 DBH-class 분포로 보아 현재의 900∼1,000m 에서 1,000∼l,100까지 이동할 것으로 예측된다. Polar Ordination에 의한 식생형의 분류는 식물사회학적 방법의 결과와 일치했다. 고도구배를 따라 개서나무는 500∼700m, 서나무는 700∼900m, 신갈나무는 900m이상에서 최고의 중요치를 나타낸다. Raunkiaer의 life-form spectrum을 남한의 것과 비교하면, 반지중식물은 5.3%, 지중식물은 5.2% 높게 나타났으며, 착생식물과 수중식물은 극히 적게 나타났다.