본 연구는 관상적 가치가 뛰어난 한반도 자생식물 너도개미 자리[Minuartia laricina (L.) Mattf.]의 산업화를 위한 대량 번 식 기술을 개발하기 위해 수행되었다. 종자 번식 실험에서는 2023년 8월 16일 형태적으로 완전히 성숙한 종자를 채종하여 사용하였으며, 종자의 내부 형태를 관찰한 결과 배가 완전히 발달하여 미숙배로 인한 형태적 휴면(MD)은 없음을 확인하였 다. 또한, 종자를 증류수에 침지시켜 수분 흡수율을 조사한 결과 수분흡수 24시간 후 약 66%의 수분 흡수율을 보여 불투수성 종피에 의한 물리적 휴면(PY)도 없음을 확인하였다. 실온 (22±2℃)에서 후숙처리(Dry after-ripening)를 0, 4, 21주 실 시 후 각각 4, 10, 15, 20, 25, 30℃로 설정된 기내 발아 실험을 진행하였다. 실험의 결과, 후숙 4주 처리 후 20℃에 치상한 종자 의 발아율이 약 76%로 가장 높았다. 후숙 처리를 하지 않은 종자는 12주 내 어떠한 온도 조건에서도 발아하지 않아 생리 적 휴면(PD)으로 판단되었다. 삽목 번식 실험에서는 줄기삽목 (Stem-cutting) 방식으로 진행하였고, 루톤 분제 처리가 발근 에 미치는 영향을 조사하였다. 루톤 분제를 처리하지 않은 처리 구는 발근율과 생존율이 100%로 나타났으며, 루톤 분제가 처리 된 삽수는 이들보다 발근율과 생존율이 통계적으로 유의하게 낮았다. 따라서 너도개미자리 종자는 생리적 휴면 종자로 분류 되며, 4주간의 후숙 처리가 휴면 타파에 효과적인 것으로 확인 되었다. 또한, 너도개미자리 삽목 번식 시 별도의 발근 촉진제 처리가 필요하지 않음을 확인하였다.
A new variety of Alfalfa (Medicago sativa L.), named 'Alfaking' was developed between 2015 and 2023 at the Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan, Republic of Korea. The variety was produced through artificial hybridization, with ‘Paravivo’ serving as the maternal line and ‘WL514’ as the paternal line. ‘Alfaking’ underwent field tests across four regions (Cheonan, Pyeongchang, Jeongeup, and Jinju) to evaluate its agronomic characteristics and forage production over two years (2022-2023). The dry matter yield of ‘Alfaking’ reached 22,516 kg/ha, which is 11% higher than the control variety, ‘Vernal.’ ‘Alfaking’ exhibited 2.1% higher crude protein content than ‘Vernal’ in forage nutritive value. The development of this new alfalfa variety, which exhibits excellent adaptability to challenging environmental conditions, is expected to enhance forage cultivation and productivity in Korea.
목적 : 본 연구는 입체시 검사법들의 재현성과 교환가능성에 대해 알아보고자 하였다. 방법 : 안과적 질환과 관련된 진단을 받은 적이 없으며 교정시력이 20/20 이상인 30명을 대상으로 하였다. 굴 절이상을 확인한 후 입체시 검사(티트무스, 랑 Ⅱ, 티엔오, 프리즈비 검사)를 각각 하루 이상의 간격을 두고 두 번 검사하였다. 검사 간의 신뢰도 분석은 급내상관계수를 이용하여 분석하였다. 결과 : 반복 검사를 통한 입체시 검사의 신뢰도 확인에서 프리즈비 검사(p=0.103, ICC=0.99) 에서만 높은 재 현성을 보였다. 입체시 검사 간의 비교에서는 프리즈비와 티엔오 검사(p=0.358, ICC=0.89)에서 좋은 호환성을 확 인할 수 있었다. 20초미만의 작은 차이를 나타내는 경우 또한 42%로 모든 검사법들의 비교 중 가장 큰 비중을 차 지하는 것으로 나타났다. 결론 : 입체시 검사의 진행은 방문 간에 일정하게 유지되는 것이 좋으나 검사 방법들의 특성에 따라 신뢰도와 호환성이 좋은 입체시 검사와 함께 평가되는 것이 필요하다. 본 연구의 결과 프리즈비 검사가 신뢰도와 호환성에서 좋은 것으로 나타나 다른 검사와 함께 평가하는 것이 유용할 것으로 사료된다.
Due to climate change and the expansion of cultivation areas through the use of reclaimed land, changes in the selection of Italian ryegrass (Lolium multiflorum L.) varieties are anticipated. This study was conducted to compare the growth characteristics before overwintering, productivity, and feed value of eight Italian ryegrass varieties with different maturing stages under the same cultivation conditions. The variety ‘Lm4ho’, a medium-maturing type, showed superior growth characteristics before overwintering, including plant height, leaf length, and leaf width. The heading date was advanced in all varieties, with a greater degree of advancement observed in varieties with earlier heading dates. When harvested at the heading stage of the early-maturing types, the dry matter yield of the medium-maturing types was not significantly different from that of the early-maturing types. However, when harvested at the heading stage of the medium-maturing types, the dry matter yield was higher than that of the early-maturing types. Specifically, ‘Lm4ho’ produced 2,518 kg/ha more than ‘Kowinearly’. The late-maturing variety IR901 and the medium-maturing varieties ‘Lm4ho’ and ‘Kowinmaster’ showed statistically superior dry matter yields. In terms of forage value, including crude protein (CP), total digestible nutrients (TDN), and relative feed value (RFV), the medium- and late-maturing types outperformed the early-maturing types. Notably, ‘Lm4ho’, ‘IR 901’, and ‘Hwasan 104’ were evaluated as suitable varieties for high-quality forage production. These results suggest that medium-maturing varieties may be suitable for double cropping in the central regions due to climate change. We propose that future breeding of Italian ryegrass should expand from focusing on cold tolerance and early-maturing varieties to include mediumand late-maturing varieties that consider both productivity and quality.
One of the key challenges for the commercialization of carbon nanotube fibers (CNTFs) is their large-scale economic production. Among CNTF spinning methods, surfactant-based wet spinning is one of the promising techniques for mass producing CNTFs. Here, we investigated how the coagulation bath composition affects the spinnability and the properties of CNTFs in surfactant-based wet spinning. We used acetone, DMAc, ethanol, and IPA as coagulants and analyzed the relationship between coagulation bath composition and the properties of CNTFs in terms of kinetic and thermodynamic coagulation parameters. From a kinetic perspective, we found that a low mass transfer rate difference (MTRD) is favorable for wet spinning. Based on this finding, we mixed the coagulant bath with solvent in a proper ratio to reduce the MTRD, which generally improved the wet spinning. We also showed that the coagulation strength, a thermodynamic parameter, should be considered. We believe that our research can contribute to establishment of surfactant-based wet spinning of CNTFs.
The growing significance of sustainable energy technologies underscores the need for safe and efficient management of spent nuclear fuels (SNFs), particularly via deep geological disposal (DGD). DGD involves the long-term isolation of SNFs from the biosphere to ensure public safety and environmental protection, necessitating materials with high corrosion resistance for DGD canisters. This study investigated the feasibility of a Cu–Ni film, fabricated via additive manufacturing (AM), as a corrosion-resistant layer for DGD canister applications. A wire-fed AM technique was used to deposit a millimeter-scale Cu–Ni film onto a carbon steel (CS) substrate. Electrochemical analyses were conducted using aerated groundwater from the KAERI underground research tunnel (KURT) as an electrolyte with an NaCl additive to characterize the oxic corrosion behavior of the Cu–Ni film. The results demonstrated that the AM-fabricated Cu–Ni film exhibited enhanced corrosion resistance (manifested as lower corrosion current density and formation of a dense passive layer) in an NaCl-supplemented groundwater solution. Extensive investigations are necessary to elucidate microstructural performance, mechanical properties, and corrosion resistance in the presence of various corroding agents to simplify the implementation of this technology for DGD canisters.
Caprine cryptosporidiosis mainly occurs in young goats, with morbidity rates of 80%–100% and mortality over 50% in goat kids. However, limited research has been conducted on the impact of Cryptosporidium parvum, a diarrhea-causing pathogen, on the intestinal microbiota of goat kids. In this study, 16S rRNA-based metataxonomic analysis was performed to compare the microbial diversity and abundance of the gut microbiota between C. parvum-infected and uninfected goat kids. In total, 12 goat fecal samples were collected, including seven naturally C. parvum-infected and five uninfected goats from Chungcheongbuk-do, Korea. After amplification of the V3–V4 hypervariable region of the bacterial 16S rRNA, high-throughput sequencing was performed. The results showed differences in the microbial composition between C. parvum-infected and uninfected groups based on beta diversity. Firmicutes and Bacteroidetes were the most dominant phyla in both groups. However, no significant difference was observed in the Bacteroidetes/Firmicutes ratio between the two groups. Compared with the uninfected group, the C. parvum-infected group showed significantly higher abundances of Tyzzerella nexillis, Lactobacillus johnsonii, Butyricicoccus pullicaecorum, Enterococcus raffinosus, Enterococcus faecalis, and Negativicoccus massiliensis, and significantly reduced abundances of Aerococcus vaginalis, Faecalicoccus pleomorphus, Oribacterium parvum, and Coprococcus comes. These findings indicate that C. parvum infection, which is associated with diarrhea in neonatal goats, induces alterations in the caprine gut microbiota.
Fluorescent bacteria were isolated from sporocarps that browned into various mushrooms during survey at places of the production in Korea. We examined the pathogenicity, biodiversity, and genetic characteristics of the 19 strains identified as Pseudomonas tolaasii by sequence analysis of 16S rRNA and White Line Assay. The results emphasize the importance of rpoB gene system, fatty acid profiles, specific and sensitive PCR assays, and lipopeptide detection for the identification of P. tolaasii. As a result of these various analyses, 17 strains (CHM03~CHM19) were identified as P. tolaasii. The phylogenetic analysis based on the 16S rRNA gene showed that all strains were clustered closest to P. tolaasii lineage, two strains (CHM01, CHM02) were not identified as P. tolaasii and have completely different genetic characteristics as a result of fatty acids profile, specific and sensitive PCR, lipopetide detection, rpoB sequence and REP-PCR analysis. Pathogenicity tests showed 17 strains produce severe brown discolouration symptoms to button mushrooms and watersoaking of sporophore tissue within three days after inoculation. But two strains did not produce discolouration symptoms. Therefore, these two strains will be further investigated for correct species identification by different biological and molecular characteristics.
수염풍뎅이(Polyphylla laticollis manchurica)는 과거에는 흔히 발견되었으나, 1970년대 이후 한반도 내 개체수 가 급격히 감소하여 2005년 환경부에 의해 멸종위기 야생생물 Ⅰ급으로 지정되었다. 또한 해당종의 분자생물학적 연구는 멸종위기종이라는 특성으로 인해 제한적으로 진행되었다. 그로 인해 NCBI 등 공공 데이터베이스에서 제공되는 서열정보들 또한 부족한 실정이다. 이 연구는 이러한 한계를 극복하고 수염풍뎅이의 유전적 특성을 규명하기 위해 생물정보학적 기술을 활용하여 전사체 분석을 진행하였다. Illumina HiSeq 2500 플랫폼을 사용하여 53,433,048개의 RNA reads를 얻었으며, Trinity와 TGICL을 이용한 De novo 어셈블리 분석을 통해 18,172개의 unigenes를 생성하였다. 생성된 unigenes는 GO, KOG, KEGG, PANM DB를 활용하여 annotation을 진행하였다. 그 결과, GO 분석에서는 ‘binding and catalytic activities’와 관련된 항목이 높은 발현을 보였으며, KOG 분석의 경우 ‘Cellular Processes and Signals’ 범주가 높은 비율을 나타내었다. KEGG 분석을 통해 2,118개의 unigenes가 metabolic 카테고리에 annotation된 것을 확인하였다. SSR 모티프 분석에서는 AT/AT (42.90%) 모티프, AAT/ATT (13.13%) 모티프 순으로 많이 나타나는 것을 확인하였다. 이 연구를 통해 분석한 결과 들을 이용하여 유전자원 및 종 정보를 실시간 제공 및 정보 공유가 가능하도록 Database 및 web-interface를 구축하 였으며, 이러한 자료들은 국내 멸종위기종인 수염풍뎅이의 고유한 유전적 특성을 발굴 및 확보할 수 있는 기반자 료로써 활용될 수 있을 것으로 사료된다.