Environmental DNA (eDNA) has emerged as a promising tool for aquatic biodiversity monitoring, yet its collection in lentic ecosystems remains technically constrained by filtration capacity and field logistics. In this study, we applied a novel eDNA concentration system, QuickConcTM, to evaluate freshwater mussel diversity in lakes, and compared its performance with the conventional GF/F filtration method. Water samples were collected from four reservoirs at surface, mid, bottom, and waterside layers, and processed using both filtration techniques. Metabarcoding of mitochondrial 16S rDNA revealed that QuickConcTM captured a higher average number of amplicon sequence variants (ASVs) and exhibited greater species richness and diversity indices (Shannon and Simpson), although the differences were not statistically significant. QuickConcTM samples showed a greater capacity to detect rare taxa and to recover higher ASV richness in certain cases, suggesting its potential to enhance biodiversity resolution. Species composition remained consistent across methods, with Cristaria plicata and Sinanodonta lauta being dominant in both cases. However, slight spatial variations in species assemblages were observed between center and waterside sampling points, highlighting the influence of habitat heterogeneity on eDNA distribution. Overall, our results demonstrate that the QuickConcTM system offers a practical and efficient alternative to traditional filtration methods for eDNA-based freshwater mussel monitoring, particularly in environments with high suspended solids. The findings underline the need for adaptive sampling strategies that consider both methodological and ecological factors when designing eDNA surveys in lentic ecosystems.
The long-tailed goral (Naemorhedus caudatus) is classified as an endangered species in South Korea due to population declines driven by human development and habitat fragmentation. This study aimed to investigate genetic characteristics and microsatellite genotypes in long-tailed goral populations using fecal samples collected from Uljin and Samcheok regions, which are geographically important habitats for the distribution and dispersal of this species in South Korea. The mean expected heterozygosity (HE) and observed heterozygosity (HO) across 10 microsatellite loci were 0.600 and 0.461 for the Uljin population and 0.644 and 0.571 for the Samcheok population, respectively. These values indicate a moderate level of genetic diversity compared to other closely related species. Genetic differentiation between the two populations had a low level, while a moderate gene flow was observed. The genetic evidence obtained in this study suggests that these two populations share a similar genetic pool, resulting in a low level of genetic differentiation between them. Therefore, they should be considered as one continuous population. Results of this study provide fundamental data and valuable genetic insights for long-term management of the long-tailed goral population in Uljin and Samcheok regions.
This paper addresses a scheduling problem aimed at minimizing makespan in a permutation flow shop with two machines and an inspection process that must be conducted at least once every certain number of outcomes from the first machine. A mathematical programming approach and a genetic algorithm, incorporating Johnson's rule and a specific mutation process, were developed to solve this problem. Johnson's rule was used to generate an initial population, while the mutation process ensured compliance with the inspection constraints. The results showed that within a computation time limit of 300 seconds, the mathematical programming approach often failed to provide optimal or feasible solutions, especially for larger job sets. For instance, when the process times of both machines were similar and the inspection time was longer, the mathematical programming approach failed to solve all 10 experiments with just 15 jobs and only had a 50% success rate for 100 jobs. In contrast, the proposed genetic algorithm solved all instances and delivered equal or superior results compared to the mathematical programming approach.
The demand for automated diagnostic facilities has increased due to the rise in high-risk infectious diseases. However, small and medium-sized centers struggle to implement full automation because of limited resources. An integrated molecular diagnostics automation system addresses this issue by integrating small-scale automated facilities for each diagnostic process. Nonetheless, determining the optimal number of facilities and human resources remains challenging. This study proposes a methodology combining discrete event simulation and a genetic algorithm to optimize job-shop facility layout in the integrated molecular diagnostics automation system. A discrete event simulation model incorporates the number of facilities, processing times, and batch sizes for each step of the molecular diagnostics process. Genetic algorithm operations, such as tournament, crossover, and mutation, are applied to derive the optimal strategy for facility layout. The proposed methodology derives optimal facility layouts for various scenarios, minimizing costs while achieving the target production volume. This methodology can serve as a decision support tool when introducing job-shop production in the integrated molecular diagnostics automation system
Natural populations of numerous species have decreased sharply in recent years, and a number of mammalian species are also now at elevated risk of extinction globally. The long-tailed goral Naemorhedus caudatus, a vulnerable and protected species designated by IUCN (International Union for Conservation of Nature) and CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora), is distributed in Northeast Asia including the Korean Peninsula. In South Korea, the Seoraksan National Park is known as the largest core habitat for the long-tailed goral population. In this study, phylogenetic relationships and population genetic features of the Seoraksan goral population were analyzed using fecal samples with both mitochondrial DNA and microsatellite markers. We found that Seoraksan gorals were the most closely related to Russian population, and also found that a unique Seoraksan lineage evolved there. In addition, the Seoraksan goral population showed higher genetic diversity than other South Korean populations, suggesting that this population might represent the most ecologically and evolutionarily important remnants of the long-tailed goral in South Korea. The Seoraksan goral population had a low level of genetic differentiation and a rather single genetic structure, suggesting that non-negligible levels of gene flow might have occurred across populations. Moreover, microsatellite genotype-based individual identification estimated that the population size was ≥81 in the Seoraksan National Park. Findings of our study suggest that effective conservation and restoration actions are needed for long-term conservation of N. caudatus in this protected area.
Vibrio vulnificus는 그람 음성 세균의 호염성 세균으로, 5월에서 10월 사이 해수 온도가 18oC 이상이고 염도가 15- 25 practical salinity units (psu)일 때 가장 활발하게 증식 한다. 전 세계적으로 해수, 강 하구, 갯벌 등 다양한 해양 환경에 서식하며, 굴, 전복 등 해산물에서 자주 검출되는 경향이 있다. 지속적인 지구온난화로 인한 해수 온도의 상 승으로 V. vulnificus의 분포 범위가 점차 확장되고 있으며, 그에 따라 비브리오 패혈증 감염에 대한 위험도가 증가하 고 있다. 본 연구에서는 수산물에서 V. vulnificus 분리, 항 생제 감수성 검사, MLST 분석, 전장 유전체 분석을 통한 병원성 유전자 확인, MIC를 통한 항생제 내성 유전자 분 석, 더 나아가 bv-brc에 등록된 아시아에서 분리된 V. vulnificus 균주들과 함께 cgMLST 분석을 진행하였다. 2023 년4월-7월까지 서울, 경기도 및 충청도 지역의 대형마트에 서 유통되는 수산물 시료 총 84건에서 V. vulnificus가 바 지락에서 총2주(2.4%) 분리되었으며, 2균주 모두 colistin 에 강한 저항성을 보였으나, V. vulnificus의 치료에 사용되 는 ciprofloxacin, tetracycline, chloramphenicol 항생제에 내 성을 보이지 않았다. Whole genome sequencing 분석 결 과, 유전자 상 두 균주는 동일한 클론으로 확인되었으며, multi-locus sequencing typing 결과 기존에 보고되지 않은 새로운 sequence type으로 확인되었다. Virulence gene 분 석 결과, 총123개의 병원성 유전자가 확인되었으며, 그 중 중요한 병원성 유전자 rtxA, vvhA, viuB, ompU유전자가 확 인되었다. 항생제 내성 유전자 분석 결과 분리된 두 균주 에서 모두 tet(34), tet(35), varG, norM 내성 유전자가 확 인되었다. cgMLST 분석을 진행한 결과 본 연구에서 분리 된 두 균주는 동일 cluster로 확인되었고, 기타 국내 및 아 시아 지역에서 분리된 V. vulnificus를 포함한 분석에서 균 주 간 역학적 연관성은 관찰되지 않았다. 이는 V. vulnificus 가 해수의 흐름을 타고 이동하여 분포 범위가 넓고 특정 지역에 일정한 특징을 가진 균이 밀집되지 않기 때문으로 보인다. 따라서 V. vulnificus로 인해 매년 사망자와 환자가 발생하는 것은 V. vulnificus가 가지는 잠재적인 위험성을 보여주고 있고, 본 연구결과가 향후 질병 발생 시 V. vulnificus의 연구에 도움이 될 것으로 보이며, 지속적으로 V. vulnificus 검출 연구, 항생제 내성 모니터링이 필요할 것으로 사료된다. 해산물을 통한 V. vulnificus 감염 위험성 이 증가하고 있는 상황에서 국내 수산물을 통한 V. vulnificus 전파 위험도에 대한 체계적 연구는 부족하다. 따라서 본 연구 결과는 수산물 생산 및 유통 단계에서 V. vulnificus 의 모니터링 및 위험도 평가의 중요성을 제시한다.
본 연구는 강원 평창군에 위치한 발왕산 산림유전자원보호구역의 관속식물상 및 식생구조를 파악하기 위하여 2023 년 3월부터 9월까지 총 5차례에 걸쳐 현지조사를 수행한 후, 67개소의 식생 자료를 대상으로 이원지표종분석법 (TWINSPAN) 을 통하여 산림식생 유형을 구분하고 평균상대중요치, 종다양성, CCA를 통해 그 생태적 특성을 분석하 였다. 발왕산 산림유전자원보호구역의 관속식물상은 81과 186속 283종 7아종 28변종 2품종으로 총 320분류군이 확인 되었다. 특산식물은 숲개별꽃, 진범 등 총 13분류군, 희귀식물은 가시오갈피 (EN) , 바늘까치밥나무 (VU) 등 총 5분류군 이 확인되었다. 식물구계학적 특정식물종은 총 118분류군이 조사되었으며, 귀화식물은 하수오, 미국가막사리 등 총 11분류군으로 귀화율은 3.4%로 나타났다. 식생유형은 복장나무-난티나무군락, 분비나무-사스래나무군락, 전나무-단풍 취군락, 소나무군락, 신갈나무전형군락 등 총 5개의 유형으로 구분되었다. 종다양도는 2.222로 VT2가 다른 식생단위에 비하여 상대적으로 높게 나타났으며, 풍부도, 균재도에서도 가장 높은 것으로 나타났다. CCA 분석 결과, 식생의 분포에 영향을 미치는 환경요인으로 해발고도, 종다양도, 암석노출도와 관계가 있는 것으로 나타났다. 보호구역 내 공간분포 특성을 파악하기 위하여 현존상관식생도를 작성한 결과, 신갈나무군락, 복장나무-난티나무군락, 신갈나무-피나무군락, 물푸레나무-층층나무군락, 아고산침활혼효림, 소나무-신갈나무군락, 소나무군락, 전나무군락 등 총 8개의 군락으로 구분되었다.
Climate change and human activities have significantly threatened plant diversity in Nigeria, leading to the imminent extinction of plant genetic resources (PGR). The collected and conserved PGR are insufficient to slow the rate of diversity loss. To address this challenge, plant breeders have initiated various improvement programs aimed at utilizing available PGR to enhance plant resilience against the severity of climate change. Despite these efforts, several limiting factors hinder the sustainable conservation of PGR in Nigeria. The lack of up-to-date information on PGR in Nigeria restricts our understanding of crop diversity. This review explores these constraints and outlines the diverse strategies employed by relevant research institutes over the years to conserve PGR. It also evaluates both in-situ and ex-situ conservation efforts in the country. Collaborations and interactions between research institutes in Nigeria focused on managing PGR are highlighted. Establishing more ex-situ fields across all ecological zones of Nigeria is emphasized as a crucial step to enhance effective conservation measures. Additional recommendations are provided to encourage the conservation and sustainable production of PGR in Nigeria.
In various machines used in industrial sites and transportation equipment, fastening structures of bolts and nuts are widely employed. However, conventional Steel sockets, classified as non-explosion-proof materials, have a high likelihood of generating sparks due to friction with components, which can lead to explosions or large-scale fires. To address this issue, this study developed a lightweight explosion-protection socket using AL-7075-T6 aluminum alloy, which is known for its excellent explosion-proof properties. However, due to the inherent characteristics of aluminum, it has lower rigidity compared to Steel, requiring the use of more expensive alloy materials. Therefore, our research team utilized Finite Element Analysis (FEA) and Multi-Objective Genetic Algorithm (MOGA) to optimize the mass and safety factor of the socket, proposing a design that simultaneously achieves both weight reduction and structural stability. The socket developed in this study is approximately 30% lighter than traditional Steel-based sockets while maintaining a safety factor of 1.2 or higher, significantly enhancing operational safety in explosive environments. This research sets a new standard in the design and manufacturing process of explosion-proof sockets and is expected to contribute to the optimization of various explosion-proof equipment in the future.
Tricholoma matsutake is a commercially valuable fungus that produces gourmet mushrooms. The artificial cultivation method that is currently used to produce fruiting bodies involves the transplantation of pine trees infected with T. matsutake from their natural habitats and the successful infection of young pine trees and mushroom production have been reported in Hongcheon. In this study, T. matsutake genetic diversity and relationships in this region were investigated. A genotype analysis was conducted on 25 fruiting bodies collected from an area approximately 2.56 km2 in size using 10 simple sequence repeat (SSR) markers. The analysis revealed 25 genotypes and 23 alleles with mean observed (HO) and expected (HE) heterozygosities of 0.312 and 0.293, respectively. The average polymorphism information content (PIC), which indicates marker polymorphism, was 0.257. A phylogenetic analysis showed no clear correlation between collection location and genetic distance; a spatial autocorrelation analysis indicated no significant genetic structure within 1600 m; and the Mantel test showed no significant correlation between genetic and geographic distances. These results were consistent with previous reports on Japanese populations. This study provides insights into the genetic diversity and structure of T. matsutake at a local scale and highlights the need for further studies across broader geographical ranges.
본 연구는 백두대간 줄기에 위치하며 산림청 지정 산림유전자원보호구역으로 지정된 희양산의 관속식물상에 대해 조사하였다. 현지 조사는 2021년 4월부터 2024년 5월까지 총 10회에 걸쳐 이루어졌으며, 조사 결과 총 447분류군 94과 268속 395종 9아종 37변종 6품종의 생육이 확인되었 다. 산림청 지정 희귀식물은 총 10종이 확인되었으며, 멸종위기종(CR)에 왕벚나무 1종(식재), 위기종(EN)에 두메닥나무 1종, 취약종(VU)에 꼬리진 달래 등 3종, 약관심종(LC)에 금강제비꽃등 5종이 포함되었다. 특히 두메닥나무는 국내 신분포지로 판단된다. 특산식물은 은꿩의다리, 청괴불나무 등 14분류군이 확인되었다. 식물구계학적 특정식물은 총 73분류군으로 IV등급에 6분류군, III등급에 21분류군, II등급에 21분류군, I등급에 25분류군 이 포함되었다. 이 결과는 향후 산림유전자원보호구역인 본 조사지역의 지속적인 보전을 위한 보호대책 마련 등의 기초자료로 활용될 것이다.