온실 내부 환경은 지역에 따라 외부 환경의 영향을 지속적으로 받는다. 본 연구는 몽골, UAE(아부다비), 호 주(퀸슬란드) 등 지역별로 구축된 한국형 스마트 온실의 환경 특성을 비교하고자 수행하였다. 몽골과 아부다비의 온실 모두 내외부 엔탈피 차이가 감소함에 따라 환기율이 증가하였다. 아부다비의 반밀폐형 온실에서는 10시부터 14시까지 평균 내부 기온이 외부 기온보다 약 7-10°C 낮았고 내부 VPD(12mbar)는 외부 VPD(56mbar)보다 4.6 배 낮았는데 이 결과는 포그 시스템 운영과 관련이 있는 것으로 보인다. 퀸즐랜드 온실의 경우, 내부 온도가 외부 온 도보다 11시 기준 약 3.81°C 높았고, 내부 엔탈피와 VPD가 외부 온도보다 높았으며, 내부와 외부의 엔탈피 차이가 증가함에 따라 환기율이 증가하였다. 이 결과로 엔탈피를 낮추는 것은 환기와, VPD를 낮추는 것은 포그 시스템 작 동과 관련이 있는 것을 알 수 있다. 또한, 작물 생육에 적합한 환경 조건을 효과적으로 관리하기 위해 엔탈피와 VPD 기반의 포그, 환기 또는 난방 시스템이 필요하다는 것을 알 수 있다.
The recent release of contaminated water from the Fukushima Daiichi Nuclear Power Plant highlights the need for accurate tritium measurement, particularly near the minimum detectable activity (MDA) of 5 Bq·L−1 set by South Korea’s Nuclear Safety and Security Commission. This study aims to improve low-level tritium measurement accuracy by optimizing the region of interest (ROI) for quench curve determination. These adjustments are crucial for separating tritium signals from background noise. Quench standards were prepared and measured using a liquid scintillation counter (LSC). Three ROIs were analyzed to assess the impact of channel selection on measurement precision: A 20-148 channel range optimized via figure of merit (FOM) analysis, a 20-250 channel range covering tritium’s full beta spectrum, and a broad 1-1024 channel range. Quench curves were obtained by fitting the counting efficiency of each ROI to the quench standards. Tritium samples with six different activity levels were prepared, and their radioactivity was calculated using the quench curves. Selecting appropriate ROIs for quench curve determination is critical for measuring low-concentration tritium accurately. This approach reduces uncertainty and emphasizes reliable methods to improve the precision and consistency of tritium measurements.
Industries that use or produce radionuclides have unintentionally released these substances into surrounding soils and sediments. To address this problem, Beautiful Environmental Construction (BEC) Co. developed the BEC’s Radioactive Soil Decontamination (BERAD) system to remove contaminants and reduce the volume of radionuclide-contaminated soils. Owing to the limited availability of radioactive isotopes such as 60Co, 90Sr, 137Cs, and uranium-contaminated soil, naturally occurring elements in soil were used in this demonstration. The soil was divided into six size fractions via manual wet sieving and the BERAD system. Then, the concentrations of uranium, cobalt, strontium, cesium, and iron in each fraction were measured. The results of both separations showed that a considerable amount of each element is retained in the finer size fractions (<0.2 mm). After BERAD separation, the corresponding values yielded 53% uranium, 45% strontium, 66% cobalt, and 53% cesium in the fine size (<0.2 mm) fractions of 35% by weight. The study found that the concentrations of these elements increased as the particle sizes decreased. Iron and micaceous minerals played a significant role in retaining the elements. The pilot scale BERAD system yielded results that were similar to those obtained via laboratory wet-sieving and was successfully demonstrated as a soil washing technology.
This study investigated the seasonal variations and environmental factors influencing soil respiration in Quercus mongolica forests at three distinct sites in South Korea: Mt. Jeombongsan, Mt. Namsan, and Mt. Jirisan. Monthly soil respiration rates were measured from 2009 to 2010 using a closed chamber method, alongside assessments of soil temperature, moisture, and organic matter. Results revealed significant seasonal and spatial variability, with the highest respiration rates recorded during summer months. Soil temperature was identified as the primary driver of respiration, showing strong positive correlations across all sites (R2=0.64 - 0.88). The temperature sensitivity (Q10) values ranged from 2.7 at Mt. Namsan to 5.7 at Mt. Jeombongsan, underscoring the heightened vulnerability of cooler, high-altitude forests to warming. Soil moisture had a dual role, promoting respiration at moderate levels but inhibiting it under saturated conditions, particularly at Mt. Jirisan. Soil organic matter content exhibited an inverse relationship with respiration rates, indicating that substrate quality, rather than quantity, predominantly governs microbial activity. Plant-soil interactions, including root respiration and litterfall decomposition, further modulated respiration patterns, with site-specific differences reflecting variations in vegetation density and ecosystem structure. These findings highlight the complexity of soil carbon dynamics in temperate forests and the critical influence of environmental factors and plant-soil processes. The study provides essential insights for improving carbon cycling models and informs climate-resilient forest management strategies. Future research should prioritize long-term monitoring and experimental manipulations to better predict soil respiration under changing climatic conditions.
In this study, carbon coating was carried out by physical vapor deposition (PVD) on SiOx surfaces to investigate the effect of the deposited carbon layer on the performance of lithium-ion batteries as a function of the asphaltene content of petroleum residues. The petroleum residue was separated into asphaltene-free petroleum residue (ASF) and asphaltene-based petroleum residue (AS) containing 12.54% asphaltene by a solvent extraction method, and the components were analyzed. The deposited carbon coating layer became thinner, with the thickness decreasing from 15.4 to 8.1 nm, as the asphaltene content of the petroleum residue increased, and a highly crystalline layer was obtained. In particular, the SiOx electrode carbon-coated with AS exhibited excellent cycling performance with an initial efficiency of 85.5% and a capacity retention rate of 94.1% after 100 cycles at a current density of 1.0 C. This is because the carbon layer with enhanced crystallinity had sufficient thickness to alleviate the volume expansion of SiOx, resulting in stable SEI layer formation and enhanced structural stability. In addition, the SiOx electrode exhibited the lowest resistance with a low impedance of 23.35 Ω, attributed to the crystalline carbon layer that enhanced electrical conductivity and the mobility of Li ions. This study demonstrated that increasing the asphaltene content of petroleum residues is the simplest strategy for preparing SiOx@C anode materials with thin, crystalline carbon layers and excellent electrochemical performance with high efficiency and high rate performance.
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.
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.
Background: The clinical application of canine mesenchymal stem cells (MSCs) necessitates efficient and safe culture methods to produce large quantities of cells. Traditionally, fetal bovine serum (FBS) has been used for MSC expansion, but it carries risks such as contamination and adverse immune responses. Methods: In this study, we investigate the efficacy and efficiency of canine allogeneic serum as an effective alternative to FBS for the in vitro culture of canine MSCs. We measured the population doubling time of canine MSCs in allogeneic serum conditions and utilized qRT-PCR, flowcytometric analysis, and cellular staining/color-metric assay for investigating its effects on cellular senescence during long-term culture and the expression of key pluripotency-related transcriptomes. Results: Our findings demonstrate that canine MSCs cultured with allogeneic serum exhibited enhanced proliferation rates, reduced cellular senescence, and lower apoptosis levels compared to those cultured with FBS. Additionally, the expression of key pluripotency-related transcription factors, including Oct4, Sox2, and Nanog, was increased in canine MSCs cultured with allogeneic serum. Conclusions: These results highlight the potential of canine allogeneic serum to provide a safer and more effective culture environment, supporting the large-scale expansion and maintenance of canine MSCs for clinical applications.
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.
Hydrogen cyanide (HCN) and hydrogen isocyanide (HNC) are isomers with similar chemical properties. However, HNC can be converted into other molecules by reactions with atomic hydrogen (H) and atomic oxygen (O), resulting in a variation of the HCN/HNC abundance ratio. These reaction rates are sensitive to gas temperature, resulting in different abundance ratios in different temperature environments. The emission of HCN and HNC was found to distribute along ring structures in the protoplanetary disk of V883 Ori. HCN exhibits a multi-ring structure consisting of inner and outer rings. The outer ring represents a genuine chemical structure, whereas the inner ring appears to display such characteristics due to the high dust continuum optical depth at the center. However, HNC is entirely depleted in the warmer inner ring, while its line intensity is similar to that of HCN in the colder outer ring. In this study, we present a chemical calculation that reproduces the observed HCN/HNC abundance ratio in the inner and outer rings. This calculation suggests that the distinct emission distribution between HCN and HNC results from a currently ongoing outburst in V883 Ori. The sublimation of HCN and HNC from grain surfaces and the conversion of HNC to HCN determine their chemical distribution in the heated, warm inner disk.
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.