Search Results (4,516)

Easier measurement of 17β-estradiol could promote the early diagnosis and treatment of medical conditions in women. In this study, we developed a fluorescence-based assay using a nucleic acid aptamer labeled with a fluorescent dye for the detection of estrogen. Upon binding to 17β-estradiol, the aptamer undergoes a conformational change, resulting in a measurable change in fluorescence intensity. The assay enables rapid detection within 30 min, with a limit of detection of 0.2 pg/mL and a linear dynamic range of 1 pg/mL–1000 pg/mL. High selectivity toward 17β-estradiol was confirmed against structurally related compounds. The method was successfully applied to human saliva samples, demonstrating high sensitivity, precision, and reproducibility with recoveries of 98.8% and coefficients of variation below 3.0%. In addition, a compact desktop fluorescence detector was developed, allowing direct measurement in polymerase chain reaction tubes without sample transfer, thereby simplifying the procedure and minimizing sample loss. These results demonstrate that the proposed system provides a simple and practical platform for estrogen detection in biological samples and has potential applications in clinical and research settings. Full article

Flood discharge observations in Japan are shifting from the conventional float-based methods to unmanned techniques such as radio-wave current meters. These approaches differ fundamentally in their measurement principles: the former is based on a Lagrangian framework, whereas the latter relies on a Eulerian framework. In this study, surface velocity fields obtained using particle image velocimetry (PIV) were used to track virtual tracers and derive Lagrangian surface velocities, providing a basis for examining the characteristics of Lagrangian and Eulerian measurements in an actual river under flood conditions. The uncertainties associated with the two frameworks were quantitatively compared, and the principal sources of uncertainty in Lagrangian measurements were identified. To achieve accurate discharge observation based on Eulerian measurements, the influences of measurement duration, subsection configuration, and vertical velocity distribution were investigated. The results suggest that measuring many points over a short duration is more effective than measuring a few points over a long duration. In a fixed-point measurement of subsurface velocity, a velocity dip was observed. Furthermore, the results quantitatively demonstrate the effects of bridge-pier wakes on the required averaging time and subsection configuration, highlighting the practical advantage of conducting observations on the upstream side of bridges. Full article

This study presents a data-driven and explainable artificial intelligence (XAI) framework for quantitatively analyzing research trends in the seismic performance of timber structures. Unlike conventional bibliometric approaches based on descriptive statistics, the framework integrates large-scale literature mining, natural language processing, topic modeling, network analysis, and SHAP-based machine learning to enable structural and temporal interpretation. A dataset of 248 journal articles from OpenAlex was processed through a unified pipeline, including domain-specific filtering, text preprocessing, and temporal balancing. Topic modeling identified eight research themes spanning traditional component-level mechanics and emerging areas such as cross-laminated timber (CLT), hybrid systems, and performance-based design. Network analysis revealed a highly interconnected structure centered on key concepts such as shear walls, connections, stiffness, and cyclic behavior. SHAP-based analysis further showed that research evolution follows a layered and cumulative pattern rather than simple topic replacement: classical themes remain foundational, while newer concepts such as CLT and structural capacity have become increasingly influential. The proposed framework provides a reproducible and scalable method for quantitatively mapping research structures and temporal dynamics in timber seismic engineering. Full article

Rice plant height is a key indicator of crop growth and phenology, yet continuous daily estimation remains challenging under limited field observations. This study proposes an interpretable Bayesian LUT-based framework to estimate rice plant height from time-series, satellite-derived GCVI, and sparse in situ measurements. Daily plant height was estimated as a posterior-weighted ensemble of multiple LUT-derived heights, together with uncertainty reflecting ambiguity among plausible growth trajectories. Applied to rice paddies in Ryugasaki City, Japan, using Harmonized Landsat–Sentinel-2 data from the 2025 growing season, the method achieved and RMSE = 7.08 cm on the validation dataset, outperforming simple baseline approaches. The estimated daily height time series also enabled evaluation of the timing at which plant height reached 70 cm, revealing clear spatial variability among fields and an associated uncertainty of approximately 10 days. Although this threshold was discussed with reference to previous studies on L-band SAR sensitivity, the present study relied solely on optical observations. Overall, the proposed framework provides a data-efficient and explainable approach for daily, spatially explicit rice growth monitoring, while current limitations include the single-region, single-year LUT construction and the simplified statistical assumptions used in the Bayesian weighting framework. Full article

Aerodynamic drag is a key factor influencing performance in high-speed winter sports, and even small reductions in drag may contribute to meaningful improvements in race time. This study investigated the effects of seam position and seam-folding direction on the aerodynamic characteristics of skiwear fabrics using wind tunnel experiments with two simplified models: a cylinder model and a wing-shaped model. In the cylinder model, the seam position directly facing the airflow was defined as 0° and shifted in 30° increments, whereas in the wing-shaped model, the seam was moved rearward from the foremost point in 5 cm increments. The inward-folded portion of the seam was arranged either toward the airflow or opposite to it. Wind tunnel tests were conducted at wind speeds ranging from 40 to 120 km/h, and drag coefficients were calculated from measured drag forces. The results show that aerodynamic drag varied with seam position in both models. In the cylinder model, the lowest drag coefficient was observed at 30° from the front, whereas in the wing-shaped model, the lowest drag was obtained at the foremost seam position (0 cm). At 100 km/h, shifting the seam position from 0 cm to 5 cm increased the drag coefficient by approximately 54.5% in seam type A and 50.0% in seam type B. These findings suggest that seam position may be a potentially relevant aerodynamic design variable in skiwear research, whereas seam-folding direction appeared to be of secondary importance under the present test conditions. However, the present conclusions are restricted to simplified experimental geometries and should not be directly generalized to specific body regions or full-garment systems. Full article

Dysregulation of the immune system, gut microbiota alteration, and epithelial dynamics in the colon contribute to the pathogenesis of inflammatory bowel disease (IBD). However, the role of epithelial dynamics, particularly epithelial regeneration, remains incompletely understood. CADM1 encodes an immunoglobulin-superfamily cell adhesion molecule involved in epithelial adhesion, immune cell interactions, and tumor suppression in colon and various cancers. Here, we investigated the role of CADM1 in IBD using a murine model of colitis induced by dextran sulfate sodium in both wild-type and conventional Cadm1-deficient (Cadm1^−/−) mice. Cadm1^−/− mice exhibited more severe colitis than wild-type mice with increased mortality (64% vs. 10%) and delayed recovery. Cadm1^−/− mice showed reduced numbers of Ki-67-positive cells in colonic crypts and delayed epithelial regeneration, whereas no significant differences were observed in epithelial apoptosis, intestinal permeability, or immune responses. Immunohistochemistry revealed that CADM1 expression was restricted to regenerative crypt cells in wild-type mice with nuclear accumulation of β-catenin and phospho-Akt. Furthermore, CADM1 overexpression in colon epithelial cells enhanced Tcf-transcriptional activity in a β-catenin-dependent manner. Immunohistochemistry of human IBD materials revealed that CADM1 expression also correlated with nuclear β-catenin accumulation in crypt epithelial cells. Collectively, CADM1 appears to promote colonic epithelial regeneration through the PI3K/Akt/β-catenin axis to protect against severe epithelial injury in IBD. Full article

The present work reveals a direct correspondence between modified theories of gravity (cosmology) and entropic cosmology based on the thermodynamics of apparent horizon. It turns out that due to the total differentiable property of entropy, the usual thermodynamic law (used for Einstein gravity) needs to be generalized for modified gravity theories having more than one thermodynamic degree of freedom (d.o.f.). For the modified theories having n number of thermodynamic d.o.f., the corresponding horizon entropy is given by $S_{\mathrm{h}}\sim S_{\mathrm{BH}}+$ terms containing the time derivatives of $S_{\mathrm{BH}}$ up to $(n-1)$-th order, and moreover, the coefficient(s) of the derivative term(s) are proportional to the modification parameter of the gravity theory (compared to the Einstein gravity; $S_{\mathrm{BH}}$ is the Bekenstein–Hawking entropy). By identifying the independent thermodynamic variables from the first law of thermodynamics, we show that the equivalent thermodynamic description of modified gravity naturally allows the time derivative of the Bekenstein–Hawking entropy in the horizon entropy. Full article

Metal oxide nanoparticles dispersed in water are difficult to recover because of their small size and colloidal stability. In this study, the interfacial adsorption behavior of Fe₂O₃, CoO, and CuO nanoparticles at hydrophobic ionic liquid (IL)–water interfaces was investigated and compared with that at molecular solvent–water interfaces. When CuO nanoparticle dispersions were shaken with hydrophobic ILs, bis(trifluoromethanesulfonyl)imide ([NTf₂]⁻) salts of 1-butyl-3-methylimidazolium ([BMIm]⁺) and 1-octyl-3-methylimidazolium ([OMIm]⁺), the nanoparticles were removed from the aqueous phase and accumulated at the IL–water interface, while negligible Cu was detected in the bulk IL phase. The removal efficiency decreased with increasing ionic strength below 0.05 mol/dm³ and increased with pH, indicating that electrostatic interactions between charged nanoparticles and the IL–water interface contribute to adsorption. Adsorption isotherms were empirically fitted with the Langmuir equation to estimate the maximum adsorption capacity. For negatively charged Fe₂O₃ and CuO nanoparticles, the maximum adsorption capacities at IL–water interfaces exceeded those at molecular solvent–water interfaces and the theoretical monolayer capacity estimated from nanoparticle size, suggesting multilayer adsorption or aggregation at the interfaces. These results demonstrate the potential of hydrophobic IL–water interfaces for the separation and recovery of metal oxide nanoparticles from aqueous media. Full article

Water-level monitoring in rice paddies supports sustainable farming, responsible water management, and greenhouse gas emission mitigation. SAR-based remote sensing is an effective alternative for estimating water levels, especially in regions where optical observations are limited. This study evaluates ten ALOS-2/PALSAR-2 L-band SAR-derived polarimetric parameters for their contribution and effectiveness in water-level estimation across rice-growing phases using random forest regression in the Subang District, which is one of the largest rice-yield areas in West Java, Indonesia. Overall, L-band polarimetric information is clearly related to water-level dynamics throughout the rice-growing cycle, confirming its strong potential for quantitative water-level retrieval. The highest estimation accuracy was achieved by integrating all polarimetric parameter groups (MAE = 1.37 cm, RMSE = 1.79 cm, R² = 0.52, r = 0.73), indicating that no single group can adequately represent the complex scattering mechanisms governing water-level variability across an entire cropping season. Variable importance analysis shows a relatively uniform contribution (7.63–12.90%), suggesting synergies across parameters in water-level estimation. Phase-specific evaluation further reveals that Phase 2, corresponding to the vegetative-to-generative transition, is the optimal temporal window for L-band SAR-based water-level retrieval due to enhanced double-bounce scattering and reduced signal saturation. While Phase 2 data maximizes physical sensitivity and correlation, whole-phase modeling provides greater robustness and lower absolute errors, making it more suitable for L-band SAR-based operational water-level monitoring applications. Full article

Proximal femoral fractures associated with osteoporosis are an important clinical problem, yet how bone quality independently influences stress distribution remains insufficiently understood. This study aimed to quantitatively compare surface stress distribution between normal and osteoporotic proximal femoral models using thermoelastic stress analysis (TSA). Fourth-generation composite femurs with identical external geometries were subjected to cyclic compressive loading at a 9° adduction angle, with different maximum loads applied to avoid structural failure (normal: 1900 N; osteoporotic: 1000 N). TSA was performed using an infrared lock-in system to obtain surface stress maps, and stress values were evaluated across key proximal regions and along the medial and lateral cortices. The osteoporotic group showed higher maximum stress values in the medial neck (−37.79 vs. −11.52 MPa), lateral neck (24.70 vs. 8.75 MPa), and intertrochanteric crest (−17.98 vs. −6.05 MPa), corresponding to approximately 1.8–3.5-fold increases compared with the normal model values normalized to 1000 N. Mean stress values were also higher by approximately 1.9–2.4-fold across regions. These results suggest that reduced bone quality is associated with increased proximal stress concentration. They may also help guide implant and fixation strategies, including stem selection and fixation configuration, by identifying regions susceptible to stress concentration under different bone quality conditions. Full article

Dissolved silicic acid (Si) in groundwater can reduce the As-removal performance of adsorbents used for treating contaminated water. However, its effects on Mg-based adsorbents remain largely unexplored. In this study, As-removal tests were conducted under various test conditions to evaluate the suitability of Mg-based adsorbents (MgO, Mg(OH)₂, and MgCO₃) for the purification of As-contaminated water in the presence of Si. As-removal performance varied significantly depending on the Mg-based adsorbent type and dosage (W_Ad0/V), As valence, and the initial As and Si (C_Si0) concentrations. In some cases, As removal improved at relatively low C_Si0; however, overall performance decreased with increasing C_Si0 for all Mg-based adsorbents. Moreover, compared with Mg(OH)_2, the performance of MgO and MgCO₃ was more strongly affected by Si. This inhibition is attributed to competition between Si and As for adsorption sites on the adsorbent surface. Furthermore, for MgO and MgCO₃, the amount of As removed by coprecipitation with secondarily generated Mg(OH)₂ aggregates was inferred to decrease with increasing C_Si0, because higher C_Si0 lowered the solution pH. Overall, MgO and Mg(OH)₂ can function effectively as adsorbents for As treatment when W_Ad0/V is appropriately selected, considering the range of Si concentrations typically found in groundwater. Full article

The global demand for food has been increasing, presenting new challenges in meeting this demand. To address this growing need, the use of coating technology through nanoemulsions shows great potential. The use of thyme essential oil stabilized by chitosan nanoparticles offers a promising and sustainable approach for the development of edible coatings. Chitosan was extracted from shrimp shell waste and used to produce nanoparticles via the ionotropic gelation method, using sodium tripolyphosphate (TPP) as a crosslinking agent. To prepare the nanoemulsions, thyme essential oil was used as the dispersed phase, combined with an aqueous phase containing chitosan nanoparticles and Tween 80 as the emulsifier. Two techniques were employed to produce nanoemulsions: high-pressure homogenization and ultrasonication. Nanoemulsion formulations with different concentrations were prepared and characterized in terms of droplet size (Z-Average) and stability using dynamic light scattering (DLS). The average droplet sizes obtained were above 100 nanometers for samples produced via high-pressure homogenization and below 100 nanometers for those prepared using ultrasonication. Analysis of variance (ANOVA) confirmed that both the method (p = 0.002) and the oil phase concentration (p < 0.001) had statistically significant effects on droplet size. Regression analysis showed that oil concentrations below 2.0 g (w/w) increased droplet size, while concentrations above 4.0 g (w/w) significantly reduced it (p < 0.05). However, physical stability tests conducted at 5 °C for 30 days showed consistent values across both formulations, with only minor fluctuations, suggesting overall good stability. Full article

Artificial intelligence (AI) systems and tools are increasingly reshaping educational practices. This study examines perspectives shared in student-focused online communities on AI’s impact on education, comparing those of computer science (CS) and business students through an analysis of Reddit posts. Using natural language processing (NLP), sentiment analysis, and Latent Dirichlet Allocation (LDA) topic modeling, we analyzed 1108 posts collected from six subreddits. Results reveal distinct thematic focuses: CS students emphasize technical aspects, including programming efficiency, coding assistance, and concerns about job displacement, while business students focus on decision-making enhancement, financial analysis applications, and operational efficiency. Sentiment analysis indicates that the Business/Finance-oriented corpus is slightly more positive than the CS-oriented corpus (51.9% vs. 50.1% positive). The CS-oriented corpus also contains a higher proportion of negative posts (36.0% vs. 33.2%). These differences reflect discipline-specific epistemological frameworks shaping AI perception. The findings provide educators with guidelines for developing tailored AI integration strategies that address discipline-specific concerns and opportunities. This study contributes to understanding how academic background influences perceptions of AI in education, offering insights for curriculum design and policy development. Full article

We studied experimentally and computationally the structures and optical properties of sulfur (S), selenium (Se) and tellurium (Te) ring clusters. We encapsulated S, Se and Te into AFI, MOR, CHA and LTA zeolites via vapor adsorption or high-pressure injection from melt and studied Raman and optical absorption spectra (RS and OAS, respectively) of zeolite single crystals with incorporated S, Se and Te ring clusters. Importantly, strict orientation of the rings in zeolite crystals allowed us to study the polarization/orientation dependency of ring RS and OAS. The obtained experimental spectra are found to be in agreement with density functional theory results (DFT using the PBE0 functional and def2-TZVP basis sets) for S₈, Se₆, Se₈, Se₁₂, Te₆ and Te₈ ring molecules. The agreement is especially good for Te rings, while for S and Se rings harmonic frequency scaling factors are required. The S and Se rings display light-induced effects, which we attribute to the presence of conical intersections between their ground and excited electronic states, resulting in isomerization and subsequent fragmentation. We consider this effect using the Se₆ ring example. This phenomenon is important for understanding photostructural changes not only in chalcogen clusters but also in bulk materials such as amorphous selenium. Full article