Graphene-reinforced aluminum (Gr/Al) nanocomposites offer exceptional mechanical properties for aerospace, automotive, and electronics applications. Precise estimation of their characteristics, including ultimate tensile strength (UTS) and Young’s modulus (YM), remains challenging due to complex atomic interactions and computational limitations of traditional methods. This study proposes a novel machine learning framework combining Molecular Dynamics (MD) simulations, Adaptive Fast Desensitized Kalman Filter (AFDKF), Diffusion Variational Graph Neural Network (DV-GNN), and Arctic Tern Optimizer (ATO) for efficient and accurate mechanical property prediction. Important variables such as graphene alignment, volume fraction, chirality, and ambient temperature are captured by the method. DV-GNN achieves a prediction accuracy of 99.9%, significantly outperforming existing ML models. The framework also demonstrates low error rates, fast computation, and scalability, providing a robust computational tool for intelligent design of high-strength, lightweight Gr/Al nanocomposites.
Constructing an efficient electron coupling path is essential for enhancing photocatalytic hydrogen evolution. Here, guided by theoretical design and experimental validation, a Graphdiyne/CoBOx (GDY/CB) ohmic junction catalyst was developed, enabling highly efficient and directional transfer of photogenerated carriers. Density functional theory (DFT) calculations reveal that interfacial bonding between GDY and CoBOx induces strong electronic coupling, suppresses electron backflow, and promotes charge delocalization. Microstructural analyses (SEM/TEM) confirm that the 2D layered GDY framework intimately contacts CoBOx nanosheets, forming a “high-speed channel” for electron migration. In situ XPS under illumination directly captures the photoinduced electron transfer from CoBOx to GDY, evidencing the establishment of a unidirectional transfer pathway. Photoelectrochemical tests, together with the above characterizations, indicate that interfacial coupling markedly enhances hydrogen evolution by reducing transport resistance and optimizing surface kinetics. The optimized GDY/CB-30% exhibits a hydrogen evolution rate of 9.91 mmol·g−1·h−1, 7.56 times higher than pristine GDY and superior to most non-noble-metal photocatalysts. This work highlights carbon-based ohmic junctions as a strategy to overcome bandgap limitations through engineered electron transport.
The electronic and phonon transport properties of MoS2 were tailored by fabricating MoS2/MWCNT nanocomposites via a hydrothermal route. Incorporation of MWCNT resulted in a 58% enhancement in electrical conductivity, reaching 327 Sm− 1 at 503 K, attributed to strong π-π interactions, reduced hopping energy of 0.228 eV and Fermi level shift toward the valence band. The MWCNT also acted as effective phonon scattering centres, reducing the thermal conductivity to 0.499 Wm− 1K− 1 at 453 K. HRTEM analysis revealed defects such as grain boundaries, dislocations and interfaces between 1D-MWCNT and 2D-MoS2, which further promoted phonon scattering. Raman spectroscopy confirmed a reduction in Debye temperature and average sound velocity, indicating lattice softening. Overall, the incorporation of MWCNT in MoS2 not only facilitates carrier transport by serving as conductive bridges between MoS2 layers but also enhances phonon scattering, thereby optimizing thermoelectric performance.
고수(Coriandrum sativum L.)는 단단한 종피와 온도 민감성으로 인해 종종 불균일한 발아를 보인다. 초기 성장을 가속화하고, 균일한 묘 소질 확보를 보장하며, 생산 주기를 단축하기 위해서는 발아 기간 동안 정밀한 환경 제어가 필수적이다. 본 연구는 고수 종자 발아에 미치는 온도와 빛의 영향을 조사하고 일관되고 균일한 묘 소질 확 보를 위한 적합한 조건을 확인하고자 수행되었다. 종자를 페트리 접시에 파종하여 식물 생장상 내에서 5가지 서로 다른 온도(10, 15, 20, 25, 30°C)와 2가지 광 조건(명조건 및 암조건) 하에 10일 동안 발아시켰다. 일일 발아율(GR) 을 기록하였으며, 이 데이터를 사용하여 평균 발아 시간(MGT), 50% 발아 시간(T50), 발아 촉진 지수(PI)를 산출하 였다. 결과에 따르면 암조건이 테스트된 모든 온도에서 발아를 촉진하는 것으로 나타났다. 가장 높은 GR은 15°C와 20°C에서 관찰되었으며, 암조건에서 각각 90%와 91%, 명조건 하에서 각각 86%와 87%에 도달하였다. 25°C에서 의 GR은 암조건에서 75%, 명조건 하에서 43%였던 반면, 30°C에서는 각각 7%와 1%로 가장 낮았다. MGT과 T50 은 20°C에서 가장 짧았으며, PI 또한 이 온도에서 가장 높았다. 또한 PI는 모든 온도 처리구에서 암조건일 때 더 높은 경향을 보였다. 그러나 암조건에서 발아한 유묘는 10일 후 황화 현상을 보였는데, 이는 광합성 활성의 감소를 나타 낸다. 결론적으로 고수 종자는 20°C 암조건에서 가장 높은 GR과 가장 빠른 발아를 나타내었다. 하지만 광합성 활 성 유도를 위해서는 유근 출현 직후 즉시 광을 공급하거나, 암조건 발아 기간을 10일 이내로 단축하는 것이 필요하 다. 이러한 결과는 적절한 온도와 광 제어가 수직 농장 시스템에서 고수의 GR을 높이고 균일한 묘 및 생산을 촉진할 수 있음을 나타낸다.
Background: Visual–gait coupling, in which saccadic eye movements regulate the body’s center of mass (CoM), is fundamental for maintaining dynamic stability. However, previous research has primarily focused on optic flow or dual-task paradigms, leaving the specific influence of parameterizing saccadic visual demands during self-paced locomotion insufficiently explored. Objects: This study investigated how saccadic visual stimulation, varying in direction (horizontal vs. vertical [VT]) and frequency (0.5 vs. 1.1 Hz), modulates spatiotemporal gait characteristics and CoM-based dynamic stability during self-paced walking on a curved non-motorized treadmill. Methods: Twenty-five healthy young adults walked for 30 seconds at a comfortable selfselected pace on a curved non-motorized treadmill under four visual conditions: forward gaze, horizontal saccades at 0.5 Hz, VT saccades at 1.1 Hz, and horizontal saccades at 1.1 Hz. Gait parameters were recorded with inertial sensors and synchronized insoles, and CoM parameters were derived from inertial measurement unit-based segment kinematics. Results: Gait speed, cadence, and stride length were greatest during horizontal saccades at 1.1 Hz, whereas stride time was longest under forward gaze (p < 0.05). Mediolateral (ML) and VT CoM displacements, as well as CoM path length, were significantly larger under horizontal 1.1 Hz compared with forward gaze and VT saccades, indicating amplified postural demands (p < 0.05). Stance duration decreased and swing duration increased during horizontal 1.1 Hz saccades (p < 0.05). Conclusion: Saccadic visual stimulation reorganized propulsion–stability balance during selfpaced walking in a direction- and frequency-specific manner, indicating the need to consider both factors when developing visuomotor gait training strategies to enhance ML control without compromising progression.
This study investigated the spatiotemporal variation of fish larvae assemblages and their relationships with environmental factors in the coastal waters of Saryang and Yokji Islands, Korea, from June 2024 to April 2025. During the study period, surface water temperature ranged from 6.1 to 30.3°C and salinity ranged from 28.25 to 33.96 psu, showing clear seasonal variability. A total of 23 fish larvae taxa belonging to 5 orders and 14 families were identified. Dominant taxa included Parablennius yatabei, Engraulis japonicus, Sebastiscus marmoratus, and Hexagrammos agrammus. Larval abundance ranged from 15 to 1,137 ind. 1,000 m-3, with the highest density and species diversity observed in early summer. Cluster analysis revealed three seasonal assemblages: summer-autumn, winter, and winter-spring groups. Redundancy analysis (RDA) indicated that temperature, salinity, and several copepod taxa were associated with fish larvae distribution, while the cumulative variance explained by the first two axes was 23.9%. These results suggest that fish larvae assemblages in the Saryang and Yokji Islands coastal area are partly related to seasonal environmental gradients and zooplankton composition, but are also influenced by multiple factors including hydrodynamic transport and coastal physical structures. This study provides baseline ecological information on seasonal fish larvae assemblages in a multiisland coastal system and highlights the ecological importance of this area as a spawning and nursery ground for coastal fish populations.
This study examined the spatiotemporal distribution and community structure of fish larvae in the coastal waters of Geoje Island, Korea, from June 2024 to April 2025, and assessed the impact of environmental factors on larvae assemblages. The abundance of fish larvae varied significantly, ranging from 63 to 12,330 individuals per 1,000 m3. A total of 20 taxa from 14 families and 6 orders were identified. Dominant taxa included Clupea pallasii, Parablennius yatabei, Hexagrammos agrammus, Engraulis japonicus, Sebastiscus marmoratus, Sebastes schlegelii, Repomucenus valenciennei, and Rudarius ercodes. Cluster and nMDS analyses identified three distinct seasonal assemblages: a summer-autumn assemblage, a transitional assemblage, and a winter-spring assemblage. The summer-autumn assemblage was dominated by coastal and pelagic species, including Engraulis japonicus and Parablennius yatabei, while the winter-spring assemblage was characterized by coldseason spawning species such as Clupea pallasii and Hexagrammos agrammus. Redundancy analysis (RDA) revealed that temperature and salinity were the primary environmental drivers of fish larvae assemblages (p<0.01). Temperature was strongly correlated with Axis-1, which represents the main environmental gradient influencing larvae assemblages. Additionally, the copepod Acartia omorii showed a strong association with Axis-2, indicating that zooplankton community composition played a secondary role in shaping larvae assemblages. Environmental variables accounted for 26.3% of the total variance, suggesting that larvae distributions were affected by environmental conditions, hydrodynamic transport, spawning strategies, and biological interactions. These findings provide essential baseline information for fisheries resource management and coastal ecosystem monitoring.
Understanding the distinct hydro-biogeochemical dynamics of lotic and lentic systems is crucial for integrated watershed management, particularly in regions with complex land-use patterns. This study investigated the spatiotemporal water quality variations in Gunsan City, Republic of Korea. Monthly monitoring was conducted at 17 sites (8 rivers and 9 reservoirs) from May 2024 to May 2025 to analyze 11 physicochemical parameters. Multivariate statistical approaches, including Factor Analysis of Mixed Data and K-means clustering, were employed to elucidate the interactions between water body types and seasonal factors. Factor analysis identified two primary gradients explaining 42.7% of the total variance: anthropogenic nutrient loading (Axis 1) and seasonal metabolic-physical drivers (Axis 2). The study revealed distinct spatial heterogeneity; rivers exhibited significantly higher electrical conductivity and nutrient concentrations (e.g., TN, TP) compared to reservoirs, clustering into a high-pollution group driven by point and non-point sources. Seasonally, rivers showed a marked concentration effect during the dry winter season due to reduced base flow, whereas reservoirs maintained relatively stable water quality attributed to the dilution capacity of larger water volumes. Shallow reservoirs like Backseokje exhibited characteristic water quality pattern, such as hypoxia related to organic matter decomposition and high vegetation cover. These findings suggest that a differentiated management approach is essential: mitigating point-source and non-point-source pollution and securing base flow for rivers during dry seasons, while regulating internal biogeochemical processes and inflows for reservoirs.
Polydeoxyribonucleotide(PDRN)는 세포 생존 및 조직 관련 신호 경로를 조절하는 것으로 알려 져 있으며, 동물 유래 및 비동물 유래 PDRN 간의 차별성은 아직 충분히 규명되지 않았다. 본 연구에서는 연어 유래 PDRN(S-PDRN), 식물-기원 미생물 유래 PDRN(L-PDRN), 그리고 PEG가 도입된 형태인 PEG-L-PDRN을 대상으로 물리화학적 특성, 세포적합성, 그리고 신호전달 특성을 비교하였다. 전기영동 분석을 통해 L-PDRN이 저분자 DNA 프로파일을 가지며 PEG-PEI 기반의 접합 과정을 거친 후에도 안정 적인 나노복합체 형성이 가능함을 확인하였다. L-PDRN과 PEG-L-PDRN은 전반적으로 S-PDRN보다 높은 세포적합성을 보였으며, 특히 PEG-L-PDRN은 장기 처리 시 가장 지속적인 MTT 기반 대사 활성 증가를 유도하였다. 세 가지 제형 모두 A2A‑연관 PKA-CREB-Akt 신호전달을 빠르게 활성화하였으나, PEG-L-PDRN만이 해당 인산화 수준을 장시간 유지하였다. 이러한 결과는 PDRN 제형 간의 기전적 차이 를 보여주며, L-PDRN 및 PEG-L-PDRN의 피부 관련 생리·생화학적 기능에 대한 후속 연구가 이루어진 다면 기존 S-PDRN의 한계를 보완할 수 있는 비동물성 대안 소재로 활용될 가능성을 시사한다.
전라남도 해남군 두륜산도립공원은 난온대림과 온대림의 경계에 있는 추이대로 기후변화에 민감하게 반응하는 지역 이다. 본 연구는 랜드셋(Landsat) 위성영상과 딥러닝(deep learning) 기법을 활용하여 두륜산도립공원의 식생을 분류하 고, 지난 40년간 난온대 상록활엽수림의 공간분포 변화 특성을 분석했다. 분석 결과, 상록활엽수림 면적은 1980년대 중반 143.2ha(4.3%)에서 2020년대 중반 191.0ha(5.8%)로 증가하였다. 특히 이 분포 범위는 특정 지형 조건에 국한되지 않고, 고도·경사·사면향·토양 조건이 서로 다른 다양한 환경으로 확대되는 양상을 보였다. 이러한 결과는 상록활엽수림 이 단순히 면적 증가를 넘어, 기존의 환경적 제약을 점진적으로 극복하며 생태적 지위를 확장해 왔음을 의미한다. 본 연구는 난온대 상록활엽수림의 공간적 확장을 정량적으로 제시함으로써, 기후변화에 대한 식생 반응을 이해하는 데 중요한 기초자료를 제공한다. 두륜산 사례는 난온대림의 장기적인 분포 변화를 예측하고, 도립공원을 포함한 자연공 원의 식생 보전·관리 전략 수립에 중요한 시사점을 제공한다.
Background: In mammals, DRP1 is a key regulator of mitochondrial fission during mitochondrial dynamics, whereas ATF5 promotes the mitochondrial unfolded protein response (UPRmt). Both pathways are essential for maintaining cellular homeostasis and protecting oocytes and embryos from external stressors. However, the relationship between ATF5 expression and DRP1 under heat stress conditions during porcine oocyte maturation remains unclear. Methods: In this study, we investigated the mitochondrial dynamics and ATF5 expression in porcine oocytes exposed to heat stress during in vitro maturation (IVM). Protein and gene expression levels were assessed using immunofluorescence staining, Western blotting, and quantitative PCR. Results: During IVM, both DRP1 and ATF5 expression were increased (p < 0.01) significantly. In contrast, heat stress markedly impaired (p < 0.05) meiotic progression and cumulus cell expansion. Mitochondrial dynamics were disrupted (p < 0.05), as fission and fusion markers displayed reciprocal changes relative to those in controls. Concomitantly, the expression of ATF proteins was significantly reduced (p < 0.01) under heat stress. Heat-stressed oocytes also exhibited decreased (p < 0.05) expression of genes involved in antioxidant defense and NAD metabolism, whereas autophagy- and apoptosis-related transcripts were significantly upregulated (p < 0.05). At the blastocyst stage, embryos derived from heat-stressed oocytes exhibited nuclear localization of the UPR-associated transcription factors ATF4, CHOP, and ATF5. Conclusions: Collectively, our findings suggest that heat stress disrupts mitochondrial dynamics and ATF5 expression during porcine oocyte maturation while the UPRmt pathway remains active during early embryonic development to mitigate heat-induced cellular damage.
The molecular dynamic simulation method is usually used to analyse microscopic fluid fields. To use this method in engineering problems with real scales of molecules needs more time and greater computer power than we have now. To overcome these limitations, the expansion method using dimensionless and similarity of physical quantities of molecules is studied and introduced for the engineering scale fluid dynamics.