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.

This study investigates the factors influencing the seed longevity of Quercus myrsinifolia, a species with recalcitrant seeds highly sensitive to desiccation and freezing. The effects of moisture content, seed collection date, and storage methods on seed viability were analyzed using exponential decay modeling. Interactions between these factors were also explored to refine conservation strategies. Seeds with moisture content above 40% demonstrated a predicted seed longevity of 2.19 years, whereas those with moisture content below 30% had seed longevity of less than 1 year. Late-season seeds collected in November and December exhibited superior germination percentages and longer predicted seed longevity (1.32 years) compared to early-season seeds collected in September and October (<1 year). In seed weight, large seeds (2.0 g) showed longer predicted seed longevity about 1.5 times greater than that of small seeds (<1.2g). Storage methods significantly affected seed longevity, with refrigerator (4°C) with silica gel maintaining viability for 2–3 years, while seeds stored at room temperature (25°C) exhibited a seed longevity of less than 1 year. Silica gel was found to prevent seed deterioration due to over-desiccation, emphasizing the importance of balanced moisture regulation. Q. myrsinifolia seeds exhibited 𝑏 values ranging from 0.30 to 2.04, demonstrating a close relationship between decay constant, moisture content, storage conditions, and seed longevity. These findings provide critical insights into optimizing seed storage and propagation strategies for Q. myrsinifolia, contributing to its conservation and ecological restoration efforts.

Background: South Korea has recently faced record-high temperatures, which have adversely affected dairy production. Holstein cows, the primary dairy breed globally, are particularly sensitive to heat stress. In contrast, Jersey cows have shown greater heat tolerance, as demonstrated by phenotypic studies. Methods: We investigated physiological and molecular responses to heat stress in Holstein and Jersey cows by measuring rectal temperature, milk yield, and average daily gain, confirming Holstein cows’ greater vulnerability. To explore molecular mechanisms, we analyzed circulating microRNA profiles from whole blood samples collected under heat stress and normal conditions using microRNA-sequencing. Differential expression patterns were compared between the two breeds to identify biological pathways associated with heat stress. Results: Four microRNAs (bta-miR-20b, bta-miR-1246, bta-miR-2284x, and bta-miR- 2284y) were significantly differentially expressed in both breeds under heat stress (|FC| ≥ 2, p < 0.05). Notably, bta-miR-20b and bta-miR-1246 were linked to corpus luteum function and progesterone biosynthesis, while bta-miR-2284x and bta-miR- 2284y were associated with immune responses. A comparison of 11 potential heat stress-related microRNAs identified in previous studies of Holstein cows revealed consistent expression trends in Jersey cows, albeit with lower fold changes, suggesting their superior heat resilience. Conclusions: Our study highlights the physiological and microRNA-based differences in heat stress responses between Holstein and Jersey cows. Jersey cows exhibited greater resilience, supported by more stable microRNA expression profiles and improved heat stress indicators, making them a promising breed for dairy production in increasingly hot climates.

This study investigated the morphological characteristics and regional variations of leaves, flowers, and seeds of Quercus myrsinifolia Blume to understand its ecological adaptation and the effects of environmental factors. Samples were collected from Jinju, Hapcheon, and Sancheong, and nine leaf traits, six flower traits, and five seed traits were analyzed. Significant regional variations were observed, with Hapcheon exhibiting the largest leaf and flower sizes, while Sancheong showed the largest and heaviest seeds. Jinju recorded the smallest values for most traits. Principal Component Analysis (PCA) revealed distinct regional groupings, with Hapcheon displaying intermediate traits, Sancheong larger traits, and Jinju smaller traits. Correlation analysis identified strong positive relationships between leaf length and width, seed length and weight, and the number of staminate flowers and catkin width, highlighting key indicators for growth. Climate factors such as temperature and precipitation significantly influenced morphological traits, with higher temperatures negatively affecting leaf and seed sizes, while precipitation showed a weak positive correlation with seed weight. Among soil factors, pH and magnesium content were closely related to morphological traits. pH exhibited a negative correlation with leaf length and petiole length, while magnesium showed a positive correlation with seed weight and leaf width. These findings underscore the significant role of environmental factors in morphological variation and provide valuable insights for developing regionally adaptive breeding strategies. These findings provide foundational data for developing region-specific breeding strategies and cultivars for Q. myrsinifolia, contributing to ecological management and climate change adaptation strategies.

산림청은 치유의 숲 등 산림을 활용하여 대상별 맞춤형 산림치유 프로그램을 기획‧개발하고 치유활동을 효율적으로 할 수 있도록 국가자격제도로 ‘산림치유지도사’를 도입하였다. 산림치유지도사 관련 법령과 정책은 자격 취득과정의 정립, 양성기관의 확대, 산림치유지도사 배출 등 단계별 과정을 거쳐 초기 제도적 안정화를 이루었다. 변화하는 환경과 증가하는 산림치유 사회적 수요에 발맞추어 보다 나은 프로그램을 제공하기 위한 인프라 조성을 위해 양성과정의 효과적인 운영과 자격제도의 개선이 필요한 시점이다. 본 연구는 2022년까지 배출된 1‧2급 산림치유지도사를 대상으로 자격증 취득 이후의 활동 현황과 산림치유지도사 교육과정 개선 방향을 중심으로 설문조사를 실시하였다. 산림치유 설문 항목은 응답자 현황과 보유 자격증 현황, 경제활동 여부, 전문가 자격 기준, 양성과정 개선방향 등으로 구성되었다. 산림치유지도사 자격증 보유자는 여성과 50대가 가장 많았으며, 대학교 졸업 이상의 학력을 보유하고 있었다. 양성과정에 관련한 공통적인 개선 요구사항으로는 ‘양성교재’와 ‘실습시간’이 차지했으며, 현장에서 프로그램을 진행할 때 필요한 업무 능력을 배양할 수 있는 과목의 교육 요구가 높았다. 본 연구 결과를 바탕으로 산림치유 자격제도의 경쟁력을 높이고, 양성교육과정을 강화하여 교육생의 만족도를 높이는 것과 함께 나아가 산림 관련 일자리 연계 등을 위한 정책 수립의 기초자료로 활용되기를 기대한다.

The aggressive scaling of dynamic random-access memory capacitors has increased the need to maintain high capacitance despite the limited physical thickness of electrodes and dielectrics. This makes it essential to use high-k dielectric materials. TiO2 has a large dielectric constant, ranging from 30~75 in the anatase phase to 90~170 in rutile phase. However, it has significant leakage current due to low energy barriers for electron conduction, which is a critical drawback. Suppressing the leakage current while scaling to achieve an equivalent oxide thickness (EOT) below 0.5 nm is necessary to control the influence of interlayers on capacitor performance. For this, Pt and Ru, with their high work function, can be used instead of a conventional TiN substrate to increase the Schottky barrier height. Additionally, forming rutile-TiO2 on RuO2 with excellent lattice compatibility by epitaxial growth can minimize leakage current. Furthermore, plasma-enhanced atomic layer deposition (PEALD) can be used to deposit a uniform thin film with high density and low defects at low temperatures, to reduce the impact of interfacial reactions on electrical properties at high temperatures. In this study, TiO2 was deposited using PEALD, using substrates of Pt and Ru treated with rapid thermal annealing at 500 and 600 °C, to compare structural, chemical, and electrical characteristics with reference to a TiN substrate. As a result, leakage current was suppressed to around 10-6 A/cm2 at 1 V, and an EOT at the 0.5 nm level was achieved.

Helicobacter pylori are known as a causative agent of gastritis, gastric duodenum and peptic ulcer, and gastric cancer, and multiple drug use is associated with various side effects in patients. The discovery of antibacterial substances against H. pylori from Korean resource plants is an important substitute for antibiotics. 52 species of Korean resource plants were collected and extracted with 50% ethanol, and antibacterial activity against H. pylori was measured using the disk diffusion method. The toxicity of plant extracts to human gastric adenocarcinoma(AGS) cells was measured by MTT assay, and the level of IL-8 secreted when gastric epithelial cells were inoculated with H. pylori was measured. As a result of measuring the antibacterial activity of H. pylori, antibacterial activity was confirmed in 38 plant extracts. The plant species with the strongest antibacterial activity were Chrysanthemum indicum, Rheum rhabarbarum, Patrinia scabiosaefolia and Petasites japonicus. C. indicum was not cytotoxic to H. pyroli-infected AGS cells and showed anti-inflammatory effects. This study's results can be used to develop healthy, functional foods and medical materials.

The chemical composition of 86 species of native plants in Korea, including plants to be afforestation, was analyzed. The chemical composition of the species analyzed was different. The species with the highest extractable content was Viburnum dilatatum (3.91%), and the species with the lowest extractable content was Ligustrum lucidum (0.11%). The lignin content ranged from 12 to 39%, with an average of 25%. The species with the highest lignin content was Chaenomeles lagenaria (39.37%). Hemicellulose content ranged from 18 to 52%, with the highest species being Thuja occidentalis (51.22%) and Eucommia ulmoides (48.84%). Cellulose content ranged from 25 to 58%, and the species with the highest content were Prunus serrulata (57.67%), Diospyros kaki (57.14%), Aesculus turbinata (53.29%), Albizia julibrissin (53.02%), and Zelkova serrata (52.29%). The chemical composition was different for each use taxon of 86 plant species. The lignin content was the highest in the fruit group and the lowest in the group other than recommended species for afforestation. Cellulose content was highest in non-reforestation-recommended tree species and lowest in fruit trees. In classification according to tree height, lignin content was higher in shrubs than in tall trees, and cellulose content was highest in tall trees. Between deciduous and evergreen trees, the lignin content was high in deciduous trees (26.46%), and the cellulose content was also high in deciduous trees (44.01%). As a result of analyzing the correlation between each compound, there was a difference. There tended to be a positive correlation between extractives and lignin content. There was a negative correlation between extractives and holocellulose content, hemicellulose and cellulose. The higher extract content affected the cellulose content much more than hemicellulose. Also, the higher the lignin content, the lower the cellulose content. The species with low lignin content and high cellulose content were Diospyros kaki and Prunus serrulata var. spontanea. This result is expected to be primary data for bioenergy, pulp industry and bioindustry.