During an investigation of indigenous prokaryotic species in the Republic of Korea, 17 bacterial strains belonging to the phylum Bacteroidota and 4 strains belonging to the phylum Bacillota were isolated from freshwater environments. These isolated bacterial strains formed a robust phylogenetic clade with type strains of the closest related bacterial species, with 16S rRNA gene sequences sharing similarities of higher than 98.7%. To date, there have been no official report of these 21 isolates in the Republic of Korea. At the genus level, these unreported species were affiliated with Mucilaginibacter and Pedobacter of class Sphingobacteriia, Flavobacterium and Gillisia of class Flavobacteriia, Hymenobacter of class Cytophagia, and Paenibacillus and Planococcus of class Bacilli. These species were further examined by performing Gram staining, analyzing their colonies and cell morphologies, and determining their basic biochemical characteristics and phylogenetic positions. Detailed descriptions of the 21 previously unreported species are provided.
Freshwater environments serve as crucial habitats for diverse microorganisms, playing essential roles alongside plants and animals within the ecosystem. Bacteria in these environments are particularly important for maintaining ecosystem functions. Among them, members of the phylum Pseudomonadota are known to be involved in processes such as nitrogen fixation, ammonia oxidation, and biofilm formation. Pseudomonadota comprises six classes: Acidithiobacillia, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Hydrogenophilia, and Zetaproteobacteria. This study reports 43 previously unrecorded species belonging to the phylum Pseudomonadota. They were isolated from various freshwater habitats in Republic of Korea. These strains were isolated and cultured using nine different standard media, with classification based on Gram staining, cell morphology, and biochemical characteristics. Species identity was determined using 16S rRNA gene sequencing, with a similarity threshold of 98.7% for designation as unreported species. Phylogenetic analysis revealed that these 43 strains were distributed across three classes, 13 orders, 28 families, and 39 genera. This research emphasizes microbial diversity in freshwater ecosystems and provides valuable insights into ecological roles and potential novel functions of unreported bacterial species in Korea.
Cucumber mosaic virus (CMV) poses a considerable threat to a diverse array of crops in global agriculture. CMV impacts commercially important cut lilies by diminishing both yield and flower quality. We used RNA sequencing (RNA-seq) to investigate the changes in gene expression in the leaves and bulbs of four distinct cultivars of cut lily, ‘Cancun,’ ‘Brunello,’ ‘Connecticut King,’ and ‘Casa Blanca’ following CMV infection. Notably, CMV affected photosynthetic processes by significantly downregulating genes associated with photosynthesis. In addition, CMV infection was detrimental to chloroplast function and energy production. We observed differential expression of genes associated with both dominant and recessive resistance pathways that are crucial for preventing virus entry, replication, and systemic spread within the plant. Based on functional annotation and differential gene expression analysis, we identified the regulatory genes involved in triggering immune responses, modulating signal transduction, and specific host factors during CMV infection. To validate the RNA-seq findings, we selected four genes involved in resistance, virus multiplication, and virus spread and analyzed them using real-time quantitative reverse transcription PCR (qRT-PCR) with specific primers. The qRT-PCR results aligned closely with those from RNA-seq, showing consistent fold-change responses for the genes that were differentially expressed, indicating that the RNA-seq results were reliable. These results deepen our understanding of the complex genetics behind plant-virus interactions while also providing information for breeding programs that aim to develop CMV-resistant lily cultivars.
As part of the 2024 research initiative, “Investigation and Discovery of Prokaryotes in Freshwater Systems,” samples were collected from diverse freshwater habitats, including both water and soil environments. Approximately 2,000 bacterial strains were isolated as single colonies and identified through 16S rRNA gene sequence analysis. Among these, 38 strains shared ≥98.7% 16S rRNA gene sequence similarities with those of known bacterial species not previously reported in Korea. These strains were thus categorized as newly recorded bacterial species in Korea. These 38 bacterial strains displayed significant phylogenetic diversities, spanning 2 phyla, 4 classes, 15 orders, 24 families, and 34 genera. These unrecorded species were classified into the following classes: Actinomycetia (with genera including Microcella, Conyzicola, Curtobacterium, Leucobacter, Microbacterium, Frigoribacterium, Lysinibacter, Streptomyces, Nonomuraea, Actinocorallia, Ruania, and Actinoplanes), Alphaproteobacteria (Paracoccus, Youngimonas, Loktanella, Corticibacterium, Neorhizobium, Onobrychidicola, Ferranicluibacter, Aureimonas, Asticcacaulis, and Novosphingobium), Betaproteobacteria (Rhodoferax, Rugamonas, and Cupriavidus), and Gammaproteobacteria (Rheinheimera, Shewanella, Kosakonia, Leclercia, Hafnia, Yersinia, Pseudomonas, Lysobacter, and Acinetobacter ). Further characterization included assessment of Gram reaction, colony and cell morphology, biochemical properties, and phylogenetic relationships. This report presents detailed phylogenetic and phenotypic characteristics of these bacterial species.
최근 몇 년 동안 높은 감도, 빠른 응답 및 쉬운 제작 공정을 갖춘 습도 센서가 상당한 주목을 받고 있다. 여기서는 PET 기판의 깍지낀 전극(IDE)에 감지 층을 증착하여 길이 대 직경의 종횡비가 낮고 (PVP-ZnO-1), 높은(PVP-ZnO-2) PVP 개질 ZnO 나노막대 센서(PVP-ZnO)의 쉬운 제작 공정을 보고 한다. PVP-ZnO-2는 PVP-ZnO-1 센서(41,647%)에 비해 85% 상대 습도(RH)에서 99,397%의 더 높은 정전용량성 습도 감도를 보였다. PVP-ZnO-2 센서는 또한 순환 습도 조건에서 응답시간 7초 및 복구시간 10초를 나타냈다. PVP-ZnO-2의 높은 습도 감도 성능의 이점을 활용하여 다양한 호흡 정도의 정전용량 변화와 모스 부호 메시징을 시연하였다. 이 연구는 높은 표면적을 갖는 고성능 나노소재 기반 습도 센서의 엄청난 잠재력을 보여준다.
본 연구는 한국에 유학 중인 몽골 대학원생들의 적응 과정을 질적으로 살펴보며, 이들의 동기, 경험, 그리고 기존 연구와 관련된 어려움에 초점 을 맞추어 분석하는 데 목적을 둔다. 설문 조사와 인터뷰를 통해 수집된 질적 데이터는 이들이 주로 한국 문화와 언어에 대한 관심과 높은 수준 의 교육을 추구하는 동기로 학업에 임하고 있음을 보여준다. 대부분의 학생들이 차별을 거의 경험하지 않았고 한국인들에게 환영받고 있다고 느끼는 한편, 다른 학생들과의 상호작용 확대를 바라고 있는 것으로 나 타났다. 본 연구는 국제 학생과 현지 학생 간의 교류 프로그램을 활성화 하고, 정서적 안정을 지원하기 위한 상담 서비스를 제공할 것을 제언하 며, 이러한 연구 결과를 확장하기 위한 향후 연구 방향을 제안한다.
Pepper is one of the most important vegetables in South Korea. It is a key ingredient in kimchi, the nation’s staple dish, and serves as the primary raw material for producing gochujang, a commonly used condiment in Korean cooking. As a result, numerous pepper varieties have been developed, including those that yield more fruit or have milder pungency. However, farmers who grow peppers tend to prefer varieties that are resistant to pests and diseases. Bacterial wilt (BW) is one of the most devastating diseases affecting peppers and is transmitted through the soil. To breed pepper varieties resistant to bacterial wilt using molecular breeding techniques, it is essential to first identify the Quantitative Trait Locus (QTL) that confers resistance to this disease. This requires conducting locus analysis with resistant cultivars. In this study, an F2 population was developed by selfing F1 hybrids, which were obtained by crossing a resistant cultivar with a susceptible cultivar, to identify QTLs associated with bacterial wilt resistance. Genotyping-by-Sequencing (GBS) analysis will be performed using the F2 population, and the results will be utilized for QTL mapping.
본 연구는 작약의 품종간 개화시기 차이와 저온에서 장기 저 장이 가능한 품종을 선발하여 절화 유통 기간을 연장하기 위하 여 수행하였다. 작약 24품종을 대상으로 2022년 국립원예특작 과학원 시험포장에서 개화시기와 절화 품질을 조사하였다. 봉오 리 상태에서 수확한 작약을 건조 저장법으로 -1℃에서 60일 저장한 후 절화 수명과 절화품질을 조사하였다. ‘의성작약’은 홑 꽃이었고 나머지 품종은 겹꽃이었다. 개화시기는 5월 10일부터 18일 사이였으며, ‘Etched Salmon’, ‘Monsieur Jules Elie’, ‘Gilbert’, ‘Henry Bockstoce’는 개화일이 5월 10일로 가장 빨랐고, ‘Elsa Sass’는 5월 18일로 가장 늦었다. 식물체 키는 74.6∼107.8cm 였고, 절화 무게는 ‘Henry Bockstoce’ 품종 이 89.8g으로 가장 무거웠고, ‘Angel Cheeks’ 품종이 26.7g으 로 가장 가벼웠다. 꽃의 주된 색은 흰색, 빨강색, 분홍색, 자주색 이었다. -1℃에서 60일간 저장 후에 꽃과 잎의 상태가 아주 양 호한 품종은 ‘Kansas’, ‘Ole Faithful’, ‘Sonw Mountain’이 었다. 절화수명은 ‘Nick Shaylor’ 품종이 8일로 가장 길었고, 다음으로 ‘Blush Queen’, ‘Elsa Sass’ 품종이 7일이었으며, ‘Gilbert’, ‘Highlight’ 품종이 1일로 가장 짧았다. 작약은 저온 장기 저장에서 일부 품종을 제외하고는 꽃과 잎에 저온장해 증 상이 발생하였다. 이와같은 결과는 작약재배시에 품종 선택과 수확후 저온 장기 저장을 통하여 유통기간을 연장하고 하고자 할 때 기초자료로 활용될 수 있을 것으로 기대된다.
As part of the research program “Freshwater Prokaryotic Organisms Research and Discovery,” freshwater samples were collected from the Nakdonggang River. After plating the samples on several culture media and incubating aerobically, approximately 900 bacterial strains were isolated and identified using 16S rRNA gene sequences. Among the bacterial isolates showing higher than 98.7% 16S rRNA gene sequence similarity with those of already confirmed bacterial species previously unreported in Korea, 29 strains were selected. These strains were phylogenetically diverse and belonged to 3 phyla, 6 classes, 13 orders, and 21 genera. At the genus level, these previously unreported species were found to be affiliated with Novosphingobium, Sphingomonas, Polymorphobacter, Croceibacterium, Devosia, Endobacterium, Agaricicola, Bradyrhizobium, Paracoccus, and Pseudotabrizicola of the class Alphaproteobacteria; Undibacterium, Azonexus, and Dechloromonas of the class Betaproteobacteria; Acinetobacter and Budvicia of the class Gammaproteobacteria; Streptomyces, Nocardioides, Mycobacterium, and Cellulomonas of the phylum Actinomycetota; Flavobacterium and Pedobacter of the phylum Bacteroidota. These species were further characterized by examining their Gram reaction, colony and cell morphologies, biochemical properties, and phylogenetic positions. Detailed descriptions of these 29 previously unreported species are provided.
Climate change has led to increased insect pests and pest distribution changes. Traditionally, chemical control using synthetic pesticides has been the main method for pest management, but the emergence of pesticide-resistant pests has become a problem. There is a need to develop new pest control agents to overcome these issues. Entomopathogenic fungi used in pest management have minimal environmental side effects and possess a mechanism of action distinct from that of synthetic pesticides. However, there is a need for the development of technologies to maximize the insecticidal effects of fungi against pests, and expressing and releasing dsRNA within the fungi can preemptively knock out the activation of the insect’s defense system, thereby enhancing the insecticidal effect. Controlling insect defense genes and using entomopathogenic fungi as bio-carriers forms a new pest management strategy. This approach, described as a “microbial insecticide agents development strategy of cassette concept, ” can versatilely modify genes and microbes. It is expected to overcome the limitations of synthetic pesticides.
본 연구는 거리화단 화훼경관 조성 전·후의 스트레스 변화 를 알아보기 위하여, 순창 소재의 경찰관 총 18명을 대상으로 타액 채취 및 설문조사를 실시하였다. 생리 측정은 타액 코르 티솔, 혈압, 심리 측정은 식물 재배 활동 수준, 스트레스수준, 거리화단 화훼경관에 대한 간이 SD 감성을 측정하였다. 타액 코르티솔, 혈압의 사전/후 비교는 대응표본 t-test, 타액 코르 티솔, 혈압의 성별에 따른 집단간 사전/후 비교는, 독립표본 t-test, 스트레스수준, 간이 SD는 윌콕슨 부호 순위 검정 등으 로 분석하였다. 화훼경관 조성 전보다 조성 후 총 코르티솔 수 치가 낮아졌고, 식물 재배 활동 수준은 높아졌으나 통계적 유 의성은 없었다. 혈압은 여자의 경우 거리화단 화훼경관 조성 전과 조성 후 모두 정상 혈압이었고, 남자의 경우 거리화단 화 훼경관 조성 전 고혈압 전단계에서 조성 후 주의혈압으로 낮 아지는 긍정적 효과가 있었다. 거리화단 화훼경관 조성 전·후 의 스트레스수준을 총 4단계(총 4단계: 단계가 높을수록 스트 레스가 높은 수준임)로 문항 전체의 총합 수치로 알아본 결과, 화훼경관 조성 전에는 4단계(50.0%), 2단계(38.9%), 3단계 (11.1%) 순이었으나, 조성 후에는 4단계(44.5%), 2, 3단계(각 22.2%), 1단계(11.1%) 순으로 거리화단 화훼경관 조성 전에 는 1단계(정상적인 스트레스 상태로 스트레스요인 자체가 심 각하지 않거나 좋은 스트레스로 받아들인 경우)가 0%에서 조 성 후 11.1%로 높아졌다. 화훼경관 조성 전·후 SD법을 이용 하여 쾌적감, 자연감, 그리고 진정감에 대해 평가한 결과, 화 훼경관 조성 후 쾌적감, 자연감, 진정감이 높은 것으로 나타났 다(p<.05). 거리화단 화훼경관에 따른 식물 재배 활동 수준과 주요 변수간의 상관관계를 알아본 결과, 화훼경관 조성 후 식 물 재배 활동 수준과 스트레스수준, 스트레스수준과 진정감은 부(-)의 상관관계, 식물 재배 활동 수준과 쾌적감, 자연감, 진정 감과는 0.5 이상의 높은 정(+)의 상관관계가 있었다(p<.05). 따라서 식물 재배 활동 수준이 높아질수록 쾌적감, 자연감, 그 리고, 진정감은 높아지고, 거리화단 화훼경관이 없는 공간보 다 화훼경관이 있는 공간에서 쾌적감, 자연감, 그리고 진정감 을 더 크게 느끼는 것으로 판단되었다. 본 연구에서 거리화단 화훼경관을 통하여 고위험군의 높은 스트레스는 줄여주고 식 물에 대한 흥미, 관심과 심리적 안정효과는 높여 줄 수 있는 유용한 가능성이 있을 것으로 생각되었다.
본 연구는 한국어 학습자들이 자신들의 언어학습 신념이 그들의 전반 적인 언어학습과 새로운 환경에 적응하는 것에 어떠한 관계가 있는지를 찾기 위함이 목적이다. 여섯 명의 한국대학교에 재학 중인 외국인 유학 생들을 대상으로 그들의 언어학습 신념에 대한 인터뷰가 진행되었다. Horwitz의 BALLI 문항을 기반으로 한 반구조적 인터뷰가 진행되었으며, 그들의 답변은 외국어 능력, 언어학습의 어려움, 언어학습의 본성, 학습 과 소통전략, 동기와 기대 등의 주제를 기반으로 비슷한 패턴을 보이는 항목별로 구분되어졌다. 연구 결과는 외국인 유학생들은 그들의 한국어 실력이 향상될수록 자신감을 가졌으며, 그들은 문화에 대한 학습이 언어 학습에 중요한 부분이라는 것을 인지했다. 또한, 가장 효과적인 학습법은 실제적인 상황과 사람들과 어울리는 것을 꼽았으며, 그들은 대학 졸업 이후에도 한국에 남아 있기를 희망했다.
Since rice is the main food in Korea, there are no regulations on corn milling yet. Corn is known as one of the world's top three food crops along with wheat and rice, and it is known that 3.5 billion people worldwide use corn for food. In addition, corn mills are not developed or sold in Korea, but the use of corn mills is increasing significantly in many countries in Southeast Asia. In the Philippines, as Korea's rice mill import increases, Korea's KAMICO (Korea Agricultural Machinery Industry Cooperative) and domestic company A agreed to develop a corn mill jointly with PHilMech, an organization affiliated with the Philippine Ministry of Agriculture. However, research on corn milling was very insignificant, so the development was carried out based on the technology of Korea's rice mill. Rice milling is performed by peeling off the skin of rice and producing brown or white rice, so it is carried out by removing the skin and cutting the skin. On the other hand, in the corn mill, the skin of the corn is peeled, pulverized and selected to produce main products suitable for edible use. Therefore, in order to develop a corn mill, processes such as peeling, transfer, grinding, sorting, and by-product separation are required, and suitable parts must be developed. In addition, the performance must be gradually improved through experiments in which corn is repeatedly milled. The Philippines produces 7.98 million tons/year of corn, which is about 100 times that of Korea, and is mostly consumed as a staple food. This is about 10% of the total crop production in the Philippines. In addition, the main cultivation complexes of corn are the mountainous regions of Tarlac or Pangasinan, and the produced corn is 72.4% of the so-called yellow corn called Arabel and Sarangani, and the remaining 27.6% are known as white corn. In this study, it was intended to produce grains of 2.5 mm or less suitable for food for yellow corn and to develop a corn mill for 200 kg per hour. Detailed conditions for development are stipulated as more than 55% of the main product recovery rate, more than 31% of the by-product recovery rate, less than 5% of the raw material loss rate, and more than 80% of the embryo dislocation rate. In this study, to achieve this, the overall process of the corn mill was developed, and the optimal conditions for the corn mill were obtained through the development of parts and empirical tests to improve performance. In addition, it was intended to achieve the development goal by evaluating and analyzing the performance of each part so that it did not conflict.
Foot-and-mouth disease (FMD), which affects cloven-hoofed animals, is economically important because of its highly contagious nature. FMD virus (FMDV), the causative agent of FMD, involves seven serotypes (O, A, Asia1, C, and SAT 1-3). Serotype Asia1 is unique to the Asian territory and is subdivided into nine genetic groups (G-I-IX) based on nucleotide variations in the VP1 sequence. Asia1 Shamir, the most representative Asia1 vaccine, is not highly protective against the Asia1/MOG/05 (G-V) lineage found in North Korea in 2007. Therefore, we investigated whether a chimeric virus strain (Asia1/MOG/Shamir), in which the VP4, VP2, and VP3 sequences of Asia1/MOG/05 were combined with the VP1 sequence of Asia1 Shamir, can simultaneously protect against both viruses. We determined the optimal viral growth conditions for the commercial utilization of this chimeric virus strain. Of the three types of cell culture media, the Cellvento medium resulted in the highest amount of antigen in the samples. The chimeric strain was proliferated in a small bioreactor to produce a test vaccine, and its immunogenicity was evaluated in pigs. The virus neutralization (VN) titer against the Asia1 Shamir virus was > 1/100 after the second immunization with the chimeric vaccine in pigs. In addition, a single dose of the test vaccine resulted in a VN titer of > 1/100 against the Asia1/MOG/05 strain. Taken together, our chimeric vaccine strain provided sufficient protection against the Asia1/MOG/05 and Asia1 Shamir viruses, suggesting its potential as a novel vaccine for both these strains.
This study explores the perceptions of Chinese engineering-major students towards their English learning experience after taking a mandatory English composition course in an EMI college. The investigation centers on first-year students’ perceptions of transitioning to EMI, with a focus on how the composition course has assisted students’ transition as a primary language support. Data were collected through a metaphor elicitation technique in which students expressed their perceptions of English learning, complemented by a thematic analysis of 86 reflection essays on the composition class. An analysis of the 334 metaphors identified students’ enhanced confidence in English, the importance of the English-using environment, positive views of learning communities, and increased agency in the learning process. It also revealed that many students were stressed and unaware of learning strategies, therefore suggesting institutional-level language support. One implication is to promote the culture of the learning community. The findings can be particularly useful for programs that are implementing language support for non-English major students.