Bare tidal flats are increasingly recognized as blue carbon reservoirs, but system-scale estimates are prone to bias when cross-shore heterogeneity is not adequately captured. We quantified sedimentary total organic carbon (TOC) content, organic carbon (OC) stocks, sequestration rates, and source composition along shore-normal transects in five Korean bare tidal flat systems during 2022-2024. Surface-layer TOC showed no significant temporal variation, but pronounced spatial gradients in OC stocks occurred among and within systems. Mud-rich Suncheon Bay recorded the highest mean OC stock (56.3 Mg C ha-1) and apparent OC sequestration rate (0.52 Mg C ha-1 yr-1), whereas the sand-dominated Nakdong River estuary exhibited the lowest (7.5 Mg C ha-1). Within-system OC stocks varied up to 6-fold; extrapolating solely from carbon-rich upper flats would overestimate system means by nearly 89%. Comparisons with sediment-type-based estimates confirmed that such extrapolations fail to capture substantial internal heterogeneity. Stable isotope profiles revealed stronger marine-derived influence in most systems, but terrestrial influence remained highest in the Nakdong River estuary despite low OC, demonstrating that source composition alone does not determine carbon storage. Downcore isotope shifts at GH3 and ND1-ND2 were broadly consistent with CRS-derived event-depth markers for Han River channel-engineering (1982) and Nakdong barrage construction (1987), suggesting that anthropogenic modifications may have influenced OC source composition. These findings provide field-based evidence that reliable system-scale OC estimation in bare tidal flats requires shore-normal transects capturing within-system heterogeneity and offer a basis for reducing bias in regional blue carbon inventories.

Microbial communities are increasingly used as bioindicators of coastal ecosystem condition, yet many studies remain limited to descriptive taxonomic analyses. This study investigated relationships between sediment chemistry and eDNA-based microbial community structure across 82 stations in Gyeonggi Bay. Specific links between pollutant concentrations and indicator taxa were identified. Shannon diversity showed no linear trend with contamination levels, whereas the Firmicutes/Proteobacteria ratio was markedly elevated at highly contaminated sites (mean 55.9, up to 136.0) compared with cleaner sites (mean 0.51). In this dataset, these taxonomic shifts provided contaminant-specific signals that the diversity index did not, indicating that taxon-based and diversity-based metrics offer complementary rather than interchangeable information. As these patterns derive from a single regional dataset, their relative utility may vary under other environmental settings. Key indicator families, including Peptostreptococcaceae and Pirellulaceae, were identified using predefined criteria combining statistical significance (p < 0.05), correlation strength (|ρ| > 0.4), and field consistency (p < 0.05). LEfSe analysis further detected 17 genera with significant discriminative power (LDA score > 3.0). Anaerobic Romboutsia and Trichococcus characterized highly contaminated sites, whereas aerobic Woeseia, Blastopirellula, Rhodopirellula, Rubripirellula, and Sulfitobacter characterized stable low-contamination sites. Spatial mapping showed strong correspondence between microbial indicators and SQG-Q gradients. These findings demonstrate that specific microbial taxa can serve as complementary biological indicators of chemical pollution and support their integration into sediment quality assessment frameworks.

Marine ecosystems in semi-enclosed Gyeonggi Bay (Yellow Sea, Korea) were surveyed at 23 stations arrayed along four discharge transects to evaluate how sediment texture and contaminants influence macrobenthic communities. A total of 186 species were recorded, yet richness tends to decrease at innermost stations. Highly simplified communities were dominated by two opportunistic species, Capitella capitata and Heteromastus filiformis. Community composition was strongly influenced by sorting and contaminants, particularly copper, cadmium, total organic carbon, and polycyclic aromatic hydrocarbons rather than distance from potential pollution sources. Diversity-based metrics tracked organic enrichment, whereas tolerance-weighted scores aligned with persistent toxic substances, revealing the risk of misclassification when a single index is used. Macrobenthic communities serve as indicators of pollution and inform integrated coastal monitoring strategies. Integrating complementary indices with chemical data therefore provides a clearer "fingerprint" of environmental stress and a stronger basis for station-scale management of patchy pollution in coastal embayment.

This study evaluated the physiological responses of four marine fish species (Lateolabrax japonicus, Sebastes schlegelii, Platichthys stellatus, and Paralichthys olivaceus) to suspended sediments (SS) generated by marine sand mining. Using oxygen consumption rate (OCR), osmolality, and mortality as endpoints, the effects of SS concentrations ranging from 0 to 10,000 mg L- 1 were assessed. L. japonicus exhibited the highest sensitive in OCR, with an EC50 of 15,812 mg L- 1 responding more rapidly to SS exposure. In contrast, S. schlegelii demonstrated the highest mortality, with an LC50 of 340,921 mg L- 1. SS exposure caused diel variations in OCR across species, highlighting the necessity of accounting for such differences. Based on the results of this study and review, species sensitivity to SS is influenced by habitat type, activity patterns, and developmental stage, emphasizing the importance of incorporating species-specific traits to accurately evaluate the ecological impacts of SS on marine ecosystems.

Persistent toxic substances (PTSs) from anthropogenic activities are a growing concern for marine ecosystems. In addition, the specific sources and ecological consequences of PTSs, particularly in coastal regions influenced by industrial and urban developments, remain insufficiently understood. This study evaluated the distribution, sources, and risks of 54 PTSs in Gyeonggi Bay. Polycyclic aromatic hydrocarbons (PAHs) ranged from 22.0 ng g-1 dw to 2710 ng g-1 dw, and alkylphenols (APs) peaked at 21,500 ng g-1 dw in source-dominated areas. Elevated levels were observed in Incheon Port and Lake Sihwa, from industrial and urban wastewater discharges. PMF modeling identified fossil fuel combustion as the main source of PAHs and natural and agriculture for metal(loid)s. Ecological risk assessments revealed significant contributions of metal(loid)s (49.1 %) and APs (39.3 %), with nonylphenols and arsenic posing the highest risks. These findings highlight the need for continuous monitoring and stricter regulations to mitigate the impacts of PTSs in marine ecosystems.

The ecosystem regulating services from tidal flats, such as removal of organic pollutants, provided by natural tidal flats are being increasingly recognized, yet quantitative evaluation remains limited. Here we evaluated a nationwide capacity of natural purification in tidal flats. Using in situ sediments from five along the Korean coast (Incheon, Gunsan, Sinan, Gwangyang, and Busan), we applied a mesocosm system informed by 18 years of riverine monitoring data from national surveys. In particular, we adopted an integrated approach, analyzing nutrient fluxes, removal rates, and their economic value. The results indicated that in all regions, the water-sediment fluxes of all nutrients showed negative values, indicating the migration of nutrients from the overlying water to the sediment. A significant (p < 0.01) difference among regions of water-sediment fluxes was primarily due to exposed nutrient concentrations. Notably, the presence of greater total nitrogen (TN) and total phosphorus (TP) purification capacities in Incheon and Nakdong sediments reflected in remaining loads of river-estuarine continuum. Nationwide, the nutrient purification capacities of Korean tidal flats (2491 km2) were estimated at 0.29 Tg N yr−1 and 0.15 Tg P yr−1, equating to economic values of 8.26 billion USD yr−1 and 8.21 billion USD yr−1, respectively. Scaling globally, the economic values for TN and TP removal by tidal flats (124,921 km2) reached 414 billion USD yr−1 and 412 billion USD yr−1. Overall, the integrated approach successfully provided the first national-scale evaluation of nutrient removal capacity in tidal flats across Korea, addressing the ecological and economic significance of tidal flats, while underscoring the need for their conservation and management strategies of coastal areas globally.

Litter decomposition is a critical driver of carbon cycling in tidal flats, yet the extent to which decomposed organic carbon is sequestered in sediments remains unclear. We studied the effects of invasive Spartina alterniflora and native Phragmites australis litter decomposition on sedimentary organic carbon sequestration. Litterbag experiments were conducted over 360 days in tidal flats. Decomposition patterns were classified as rapid, moderate, and slow. Over 60 % of the litter carbon decomposed within the first 60 days in salt marsh (vegetated). In the bare tidal flat (unvegetated), S. alterniflora litter decomposed faster than P. australis litter. Bacterial composition shifted over time, being dominated sequentially by Bacteroidales, Bacillales, and then Pseudomonadales. Habitats with low Bacteroidales abundances showed lower initial decomposition rates. The decomposed carbon showed limited mobility and remained near the litter. These findings provide insights into the effects of litter decomposition on sedimentary organic carbon and its dynamics within sediments.

Dynamic communication between hepatocytes and the environment is critical in hepatocellular carcinoma (HCC) development. Clinical immunotherapy against HCC is currently unsatisfactory and needs more systemic considerations, including the identification of new biomarkers and immune checkpoints. Transmembrane 4 L six family member 5 (TM4SF5) is known to promote HCC, but it remains unclear how cancerous hepatocytes avoid immune surveillance and whether avoidance can be blocked. We investigated how TM4SF5-mediated hepatic tumorigenesis avoids surveillance by natural killer (NK) cells, which are prevalent in the liver, and whether the avoidance can be blocked by anti-TM4SF5 agents. We used comprehensive structure activity relationship analysis to identify TM4SF5-specific isoxazole (TSI)-based small molecules that inhibit TM4SF5-mediated effects. TM4SF5 expressed by hepatocytes reduced NK cell cytotoxicity by downregulating stimulatory ligands/receptors, including signaling lymphocytic activation molecule family member 7 (SLAMF7). TM4SF5 bound SLAMF7 depending on N-glycosylation and caused intracellular trafficking of SLAMF7 from the plasma membrane to lysosomes for degradation. TSI treatments in cell lines and animal models of HCC blocked this binding, intracellular trafficking, and downregulation, resulting in higher levels of stimulatory NK cell ligands. In mouse xenograft models, TSI treatment abrogated HCC development by increasing the abundance and dispersion of Slamf7-positive cells in liver tissues, recapitulating the phenotype of Tm4sf5-knockout mice and indicating TSI-mediated restoration of NK cell surveillance. These findings suggest that TSIs can inhibit TM4SF5-mediated liver carcinogenesis by increasing NK cell surveillance.

If the body is not seen as a combination of cells, DNA, and proteins in East Asian medicine, the logic of treatment will differ from that of biomedicine. Descola's monumental work on plural ontologies and their connectedness of social practices advocates ethnographic investigations of how the plurality of body-ontologies are overlapped with medical practices of various medical traditions. Drawing on anthropological fieldwork on Korean medicine in South Korea, this study examines the ontological ground of acupuncture practice. It provides a case of an emerging new acupuncture method, Mind Acupuncture, in Korean medicine as an example of ontological anthropology of medicine. This study shows that a new acupuncture practice emerges not by discovering a new entity of the universal biomedical body, but by expanding and materializing the ontological network of East Asian medicine. This study foregrounds the significance of ontology, the undeniable premise of medical practice that is socially and historically situated.

국어사 연구가 한국어 통시태의 원인을 규명하고자 하는 방향으로 나아감에 따라 대조언어학적 연구 방법론이 활발히 이용되고 있다. 언어 유형론과 문법화로 대변되 는 대조언어학적 연구 방법론은 언어 보편성의 개념을 통해 자료의 공백을 보완하여 한국어 통시태 연구에 여러 기여를 했다. 그러나 한편으로는 이론이 중심이 되는 국 어사 연구에 대한 우려가 없는 것도 아니었다. 이 글에서는 언어 유형론의 연구 성과 가 국어사 연구에 기여한 바를 비판적으로 검토하고, 최근 언어 유형론과 문법화 연 구가 보편성의 추구 속에 가려졌던 개별 언어의 특수성과 지역성에 초점을 맞추고 있 다는 사실에 주목하여, 국어사 연구 또한 자료 중심으로 이루어져야 할 필요성이 있 음을 주장하였다. 특히 자료와 이론이 배치될 때 자료가 더 중시되어야 함을 강조하 였다. 또 표면적 유사성에 이끌린 대조 연구는 지양하고 언어 체계를 전체적으로 조 망해야 할 필요성도 논의하였다. 여기에 1차 자료를 중심으로 하는 연구까지 더해진 다면 언어 유형론의 연구 성과를 적용하는 데에서 벗어나 국어사 연구가 일반언어학 과 역사언어학 연구에 기여하는 방향으로 나아갈 수 있음을 논의하였다.

This study compared the safety of general anesthesia (GA) and intravenous sedation (IVS) in patients who underwent extraction of one or more third molars. Data from 1,260 patients (GA group, n = 1,043; IVS group, n = 217) were retrospectively analyzed, including demographics, preoperative data, intraoperative hemodynamic parameters (blood pressure, heart rate, and oxygen saturation level), and medications administered intraoperatively and postoperatively. The incidence of intraoperative circulatory variations, surgery and anesthesia durations, postoperative complications, and medication use were assessed and compared. The GA group had longer anesthesia and surgery durations, a higher incidence of hypotension, and a higher frequency of postoperative analgesic use than the IVS group. Dexmedetomidine was the most frequently used sedative agent. The IVS group had a lower incidence of intraoperative hypotension but they had a higher need for vasopressors in the recovery room. Both anesthesia methods maintained satisfactory oxygen saturation levels and sufficient anesthesia throughout the procedure, but they showed different characteristics regarding the duration of surgery and anesthesia duration, hemodynamic stability, and postoperative analgesic needs. IVS may be preferable for patients at risk of cardiovascular complications such as hypotension or tachycardia during surgery.

Natural purification of pollutants is highly recognized as regulating ecosystem services; however, the purification capacity of tidal flats remains largely unknown and/or unquantified. A 60-day mesocosm transplant experiment was conducted in situ to assess the purification capacity of natural tidal flats. We adopted the advanced sediment quality triad approach, monitoring 10 endpoints, including chemical reduction, toxicity changes, and community recoveries. The results indicated that contaminated sediments rapidly recovered over time, particularly > 50% within a day, then slowly recovered up to ∼ 70% in a given period (60 days). A significant early reduction of parent pollutants was evidenced across all treatments, primarily due to active bacterial decomposition. Notably, the presence of benthic fauna and vegetated halophytes in the treatments significantly enhanced the purification of pollutants in both efficacy and efficiency. A forecast linear modeling further suggested additive effects of biota on the natural purification of tidal flats, reducing a full recovery time from 500 to 300 days. Overall, the triad approach with machine learning practices successfully demonstrated quantitative insight into the integrated assessment of natural purification.

Limpets are a key taxon regulating the benthic community structure and serving as prey for various predators in rocky shores, however, their role in food web dynamics is still unclear. To determine environmental factors influencing the limpet diet, carbon and nitrogen stable isotopes in limpets and food sources were analyzed on three different coastal habitats. Sediment organic matter contributed the most (86 %) to the limpet diet in bedrocks around tidal flats with abundant sediment supply from the terrestrial matter inflow and the sediment resuspension. Microphytobenthos and macroalgae were the main food sources (57 % and 20 %, respectively) for the limpets around beaches, where benthic flora was abundant. Limpets in bedrocks, erosional habitat, primarily consumed relatively abundant phytoplankton (33 %) and microphytobenthos (28 %). Contrary to previous studies, habitat type, rather than latitude or seawater characteristics, was the most important factor determining the limpet diet. This result also suggests that limpets are non-selective scraper that consume abundant food sources.

As the limitations of conventional radio communications between satellites and the ground become apparent, various experiments are being conducted around the world to overcome them with space laser communication. In this study, we address the development of our own optical communications terminal (OCT) and optical ground station (OGS) and the experiments of free-space optical communication (FSOC) using them. Using a 30 mm-diameter OCT and a 250 mm-diameter portable OGS telescope, as well as commercial 10 Gbps SFP+ modules and media converters, we successfully transmitted and received 4K high-definition multimedia interface (HDMI) signals through 1,550 nm optical laser beam. The transmission and reception distances of the experiment were 3, 9, and 20 km, respectively, and the received signal strength at each distance was +6.1, –2.8, and –10.9 dBm, respectively. It was demonstrated that the 4K HDMI video lasted for over 10 minutes.

Ligand-specific binding interactions of xenobiotics with receptor proteins form the basis of cytotoxicity-based hazard assessment. Computational approaches enable predictive hazard assessment for a large number of chemicals in a high-throughput manner, minimizing the use of animal testing. However, in silico models for predicting mechanisms of toxic actions and potencies are difficult to develop because toxicity datasets or comprehensive understanding of the complicated kinetic process of ligand-receptor interactions are needed for model development. In this study, a directional reactive binding factor (DRBF) model based on first principles was used to predict cytotoxicity potencies of agonists of the aryl hydrocarbon receptor (AhR) for 16 different polycyclic aromatic hydrocarbons (PAHs). Molecular dynamics were simulated by accounting for the directional configuration factor toward receptor protein and the factor of binding to the Per-Arnt-Sim (PAS) domain. When comparing the experimental results of toxic potencies from in vitro bioassays with the predictions among two different in silico models, including quantitative structure-activity relationship (QSAR) and molecular docking models, the DRBF model exhibited the highest model performance (R2 = 0.90 and p < 0.01). Our results showed that the DRBF model based on first principles and molecular and computational structural biology could serve as a novel framework to advance next generation hazard assessment for high-throughput screening of chemical substances.

Microalgal bioassays were conducted to evaluate the ecotoxicological effects of suspended sediments (SS) collected from coastal environments. Growth inhibition was assessed for six microalgal species, and multiple endpoints were measured using flow cytometry (FCM) and pulse-amplitude modulation (PAM) fluorometry for three species (Dunaliella tertiolecta, Isochrysis galbana, and Phaeodactylum tricornutum). Among these, the EC50 for growth inhibition of D. tertiolecta (6700 mg L-1) was notably lower compared to the other species, and among several endpoints, esterase activity was the most inhibited. Species-specific responses to SS exposure were identified, with D. tertiolecta exhibiting greater susceptibility across most endpoints. Meanwhile, measurements of Fo', Fm', and Y(NPQ) in P. tricornutum using PAM fluorometry revealed greater sensitivity. Based on the results of this study and review, the tentative predicted no-effect concentration was calculated as 12.1 mg L-1. Overall, this study provides novel insights into SS ecotoxicity, establishing a crucial baseline for future investigations.

블루카본 생태계(Blue carbon ecosystems, BCEs)는 탄소 중립을 달성하기 위한 맹그로브 숲, 잘피 숲, 염습지를 포함하고 최근 지구온난화로 인한 기후변화에 큰 영향을 주는 높은 이산화탄소(CO₂)를 흡수하는 탄소흡수원의 역할로 부각되고 있다. 기존 연구들은 CO₂ 흡수원의 역할에 대해 많은 연구가 진행되었으나, 현재 COVID-19 팬데믹으로 인한 해양환경변화에 대한 연구는 미비한 실정이다. 본 연구에서는 COVID-19 팬데믹 전후로 “블루카본”과 관련된 연구 키워드를 비교하여 블루카본 연구 동향을 확인하였으며 전세계 발전소 및 산업활동을 통한 CO₂ 배출량을 비교하였다. COVID-19 팬데믹 이후 러시아(18%)에서 CO₂ 배출량이 증가한 반면 영국(17%)에서는 CO₂ 배출량이 감소했다. 전세계적으로는 화석 CO₂ 배출량(EFOS)과 대기 중 CO2 농도(GATM)는 팬데믹 이후 감소하였으며, 해양생태계 CO₂ 흡수량과 화석 CO₂ 배출량(p 0.001) 그리고 대기 중 CO₂ 농도(p 0.001)와 유의한 양의 상관관계를 보였다. 또한 블루카본 생태계의 탄소 잠재량 분석 결과, 블루카본 생태계 중 맹그로브 숲의 맹그로브 나무(20.8 Gt CO2)와 퇴적물(0.03 Gt CO₂)이 가장 높은 탄소 흡수원으로 나타났다. 해저지형 중에서는 해연/해저분지(6.76 Gt CO₂)에서 가장 높은 탄소 잠재량을 확인하였다. 전세계적으로 COVID-19 팬데믹에 따른 국경봉쇄, 이동제한 그리고 산업활동의 감소는 대기중 CO₂ 배출량(5%)을 감소시켰으며, 해양으로 흡수량(1%)은 증가한 것으로 보인다. COVID-19 팬데믹 이후 전세계 총 탄소수치(5.5%)는 감소하였다. 본 연구 결과는 COVID-19 팬데믹으로 생긴 사회적 제약에 따른 CO₂ 배출과 블루카본에 대한 데이터를 확립해야 할 필요성을 다루며, 전세계적으로 블루카본 생태의 중요성을 강조한다.

국제사회는 해양의 지속가능한 발전을 위해 인류가 나아갈 방향과 목표를 제시하고 그 목표에 달성하기 위해 다양한 노력을 기울이고 있다. 그러나 국제사회가 COVID-19 팬데믹에 직면하게 되면서 해양환경 문제가 악화되고 있다. 본 연구에서는 해양건강성지수(Ocean Health Index, OHI)의 목표 점수 10개를 이용하여 2012년부터 2020년까지의 대한민국과 전세계 국가의 해양건강성을 정량적으로 평가하고 비교 분석하였다. 대한민국의 COVID-19 발생 전(2019년)과 후(2020년)의 해양건강성지수 목표 별 점수 변화는 ‘식량공급(-1.08)’, ‘관광 및 여가(-0.66)’, ‘생물다양성(-0.11)’, ‘장소성(0.02)’, ‘깨끗한 물(0.19)’, ‘영세어업의 기회(0.19)’, ‘천연물(4.46)’ 순으로 나타났다. 대한민국의 ‘탄소 저장’과 ‘연안 보호’ 점수는 자료가 부족하기 때문에 도출하지 못하였으며 이 항목에 대한 연구가 필수적이다. 대한민국과 연안을 공유하고 있는 국가들 중에서 COVID-19 이후 가장 큰 해양건강성지수 감소폭을 보인 경우는 러시아의 ‘연안 보호(-4.02)’였다. 전세계적으로 대양에 위치하는 대부분의 섬나라가 지속적으로 높은 해양건강성지수를 보이며 아프리카를 제외하고 OECD 가입국이 적은 남아메리카(-0.69)와 오세아니아(-0.54)에서 평균 해양건강성지수가 가장 크게 감소하였다. 대한민국의 해양 생태, 사회 및 경제적 시스템 현황을 평가하고 COVID-19 팬데믹의 교란에 따른 해양건강성 변화를 확인하여 회복에 집중이 필요한 목표 항목을 구체화하였다. 본 연구 결과는 향후 해양환경의 지속가능한 보전을 위한 방향성 연구에 기초데이터로 활용될 수 있을 것이다.

The ever-increasing energy demand and global warming caused by fossil fuels push for the exploration of sustainable and eco-friendly energy sources. Waste thermal energy has been considered as one of the promising candidates for sustainable power generation as it is abundantly available everywhere in our daily lives. Recently, thermo-electrochemical cells based on the temperature-dependent redox potential have been intensely studied for efficiently harnessing low-grade waste heat. Despite considerable progress in improving thermocell performance, no attempt was made to develop electrode materials from renewable precursors. In this work, we report the synthesis of a porous carbon electrode from mandarin peel waste through carbonization and activation processes. The influence of carbonization temperature and activating agent/carbon precursor ratio on the performance of thermocell was studied to optimize the microstructure and elemental composition of electrode materials. Due to its well-developed pore structure and nitrogen doping, the mandarin peel-derived electrodes carbonized at 800 °C delivered the maximum power density. The areal power density (P) of 193.4 mW m−2 and P/(ΔT)2 of 0.236 mW m−2 K−2 were achieved at ΔT of 28.6 K. However, KOH-activated electrodes showed no performance enhancement regardless of activating agent/carbon precursor ratio. The electrode material developed here worked well under different temperature differences, proving its feasibility in harvesting electrical energy from various types of waste heat sources.