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Biomarker, the short form of “biological marker”, appeared in the scientific literature in the 1940s. Since then, many different definitions have been suggested, but a generally applicable explanation of the term biomarker in science is extremely challenging. The word biomarker is found in 1.3 million articles in the scientific database PubMed^® that currently comprises more than 39 million citations for biomedical literature. Biomarkers are closely associated with human health and disease. The present article attempts to approach and evaluate the multifaceted term “biomarker” from a clinical perspective by searching the PubMed database. The search term biomarker was combined with other search terms related to medicine, physiology, biochemistry, and chemistry. Currently generally accepted clinical biomarkers, such as the high-molecular-mass N-terminal prohormone of brain natriuretic peptide (NT-proBNP, 60%), prostate-specific antigen (PSA, 67%), and troponin (37%), serve as a kind of positive control. The combination of the search term biomarker with selected low-molecular substances of clinically non-validated and hence rather experimental character yielded surprisingly high fractions of 41% for 8-iso-prostaglandin F_2α, 39% for symmetric dimethylarginine (SDMA), and 28% for asymmetric dimethylarginine (ADMA). The results of our survey are presented and discussed in detail for a wide spectrum of diseases. We focused on mechanisms that are assumed to underlie the biological activity and specificity of biomarkers. We also considered potential roles of the analytical chemistry of biomarkers including the emerging metabolomics and proteomics. Reliable analytical methods have been used for the quantification of the isomeric low-molecular-mass ADMA and SDMA in human biological samples. ADMA, but not SDMA, is considered an endogenous inhibitor of the endothelium-derived nitric oxide (NO) synthesis, one of the most potent endogenous vasodilators. Paradoxically, the utility of ADMA and SDMA as biomarkers in the renal and cardiovascular systems seems to contradict their main biological activity. This prominent pair is representative of many biomarkers and reveals that the supposed biomarker utility is likely to be predicated on not yet considered biological activity. The majority of human diseases are heterogenic, affect many organs and seem to include different and overlapping biochemical pathways. In recent years, especially proteomic studies provided a series of new potential candidate biomarkers. However, such biomarkers must still be validated in the clinic before they can be introduced into clinical practice. This is perhaps the most critical phase in the discovery of disease biomarkers. Our analysis reveals that the area of biomarker research is highly challenging. With minor exceptions, there is no specific biomarker for a single disease. In addition to clinical examinations, a combination of several biomarkers seems to be needed for reliable diagnosis and therapy. Analytical chemistry, especially proteomics, delivers a huge amount of data, which may complicate and even hinder progress in this area. Specific quantitative analysis of candidate biomarkers observed by proteomics (and metabolomics) is highly recommended to proceed with the same biological samples from studies in which the biomarkers were discovered. Full article

The long-tailed goral (Naemorhedus caudatus) is facing severe habitat fragmentation along the Baekdudaegan Mountain Range, South Korea, due to expanding anthropogenic infrastructures and ASF fence installations. To evaluate the evolutionary impacts of these barriers, we assessed the genome-wide genetic diversity and structural connectivity of South Korean goral populations using a high-resolution triple-digest restriction site-associated DNA sequencing (3-RADseq) framework. Out of 36 biological samples collected across regional demes, 34 individuals were successfully genotyped, yielding an initial variant pool of 68,041 raw single nucleotide polymorphisms (SNPs) that filtered down to 9908 high-quality independent SNPs. Bayesian model clustering and principal coordinate analysis consistently identified K = 2 as the optimal number of genetic clusters, resolving a deep, distinct genetic split between the continuous Northern and Southern populations. This pronounced genetic structuring indicates severely restricted contemporary gene flow, heightening vulnerability to genetic drift and inbreeding depression within isolated terminal patches. Our genomic evidence suggests that single-protected-area approaches are insufficient; effective conservation priorities must focus on restoring landscape continuity and ecological corridors to revive historical migration pathways and preserve the adaptive potential of this endangered mountain ungulate. Full article

Background/Objectives: A taller-than-wide shape is considered a suspicious ultrasound feature in the assessment of thyroid nodules. Although previous studies indicate an association with malignancy, its predictive value may vary depending on the population, methodology and measurement criteria. This study aimed to evaluate the diagnostic significance of the TTW feature and selected nodule dimensions in predicting malignancy risk. Methods: A retrospective observational study was conducted including 367 patients with thyroid nodules referred for fine-needle aspiration biopsy. Nodule height, width and the height-to-width ratio were assessed and compared with cytological outcomes according to the Bethesda classification. Spearman rank correlation and logistic regression analyses were performed, and the predictive value of the TTW ratio was evaluated using receiver operating characteristic analysis. Results: A statistically significant but weak positive correlation was observed between Bethesda category and both nodule height and the product of height and width (p < 0.05; r < 0.3). No significant association was found between the TTW ratio and lesions requiring further clinical evaluation and potential surgical management (OR = 1.03; p = 0.931). The area under the ROC curve for the TTW ratio was 0.497, indicating limited discriminatory performance between benign and potentially malignant lesions. Conclusions: In this cohort, the TTW feature showed limited predictive value in assessing malignancy risk. It should not be used as a standalone criterion for biopsy or surgery, but interpreted as part of a comprehensive ultrasound-based risk assessment together with cytological findings. Further studies in larger populations and with standardized ultrasound measurement protocols are warranted. Full article

Mountain transition zones are highly sensitive to environmental change, yet the nonlinear coupling between topography and hydroclimate in controlling vegetation Net Primary Productivity (NPP) remains insufficiently constrained. Here, we reconstructed a 2003–2025 annual NPP time series for the West Qinling Mountains using a Carnegie–Ames–Stanford Approach (CASA)-based workflow that integrated Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation products, fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis for land (ERA5-Land) meteorological data, Shuttle Radar Topography Mission (SRTM) topography, and an Aridity Index (AI) dataset. Product-based validation against the annual MOD17A3HGF dataset indicated strong agreement, with a 23-year mean spatial Spearman correlation of 0.823 and a mean annual Pearson correlation of 0.773. The reconstructed dataset showed that 98.50% of the study area experienced increasing NPP, including 50.26% with significant increases, and the domain-wide mean Sen slope reached approximately 3.08 g C m⁻² yr⁻¹. Factor detection further showed that radiation (q = 0.253), elevation (q = 0.252), and temperature (q = 0.249) were the dominant single controls, whereas Aridity–Temperature (q = 0.367) and Elevation–Aridity (q = 0.367) represented the strongest interactions. The concentration of the strongest gains in gentle-slope and moderate-aridity settings suggests that vegetation recovery is maximized where topographic buffering and water-energy balance are jointly optimized. These results strengthen the interpretation of NPP dynamics in mountainous climate-transition environments and provide a basis for spatially targeted ecological restoration, regional carbon-budget assessment, and climate adaptation planning. Full article

Zeolites are porous aluminosilicate crystalline materials that are widely used for the adsorption of volatile organic compounds (VOCs). The synthesis of zeolites without organic structure-directing agents (OSDAs) is attractive because of its low cost and environmental friendliness. In this study, analcime and the ZSM-5 zeolite were synthesized from natural diatomite under OSDA-free conditions through different crystallization routes. Analcime was prepared by regulating the hydrothermal conditions, while the ZSM-5 zeolite was synthesized by combining hydrothermal condition regulation with seed-induced crystallization. Hydrochloric acid modification was further used to improve the pore structures and adsorption properties of the zeolites. The optimum acid treatment conditions were 1.0 mol·L⁻¹ HCl for analcime and 0.5 mol·L⁻¹ HCl for the ZSM-5 zeolite. After acid modification, the specific surface area and pore volume of analcime increased to 271.7 m²·g⁻¹ and 0.130 cm³·g⁻¹, respectively, and its tolune adsorption capacity increased from 18.3 mg·g⁻¹ to 23.2 mg·g⁻¹, corresponding to a 26.6% improvement. For the ZSM-5 zeolite, the optimal modified sample showed a specific surface area of 307.9 m²·g⁻¹, a pore volume of 0.172 cm³·g⁻¹, and a toluene adsorption capacity of 65.4 mg·g⁻¹, which was 5.5% higher than that of the unmodified sample. Adsorption kinetic analysis indicated that pore diffusion played an important role in toluene adsorption, while acid modification introduced additional acid sites that contributed to chemisorption. Overall, the ZSM-5 zeolite showed a higher adsorption capacity than analcime because of its larger surface area, higher pore volume, and more accessible adsorption sites. This study provides a low-cost and environmentally friendly route for preparing diatomite-derived zeolite adsorbents for VOC removal. Full article

As an innovative ecological material widely adopted for surface protection of hydraulic soil–cement slope composites, 3D ecological slope protection mats remain insufficiently studied in terms of their anti-scour capacity under hydrodynamic erosion. This work combines physical model tests and numerical simulations to investigate its scour resistance, and adopts a radial basis function (RBF) neural network-based intelligent inversion method to calibrate numerical model parameters. Physical test results demonstrate that longer vegetation growing periods effectively strengthen slope anti-scouring performance. At 2 m/s flow velocity, extending the growth period from 2 months to 3 and 4 months increases bed shear stress of 3D ecological protection mat specimens by 41% and 19%, reduces soil loss by 49% and 33%, and decreases scour depth by 23% and 13%. Both scour depth and soil loss rise rapidly initially before leveling off, with larger ultimate values under higher flow velocities. The established numerical model achieves a 3.1% relative error between inverted and measured data, proving high inversion accuracy. Simulations under 1~5 m/s flow velocities reveal that flow velocity decreases significantly over the protected slope, and scour depth and scouring area expand gradually with increasing flow velocity. Full article

Quenched and tempered (Q+T) bolt steels are widely used in key load-bearing structures such as bridges, wind power equipment, pressure vessels and engineering machinery, but they are susceptible to hydrogen-induced cracking under applied stress during service. In this study, a bolt steel was subjected to Q+T heat treatment, including quenching at 850, 900, 950, 1000 and 1050 °C, followed by tempering at 500 °C. Microstructural characterization, hydrogen permeation tests, and slow strain rate tensile tests were conducted to investigate the effects of quenching temperature on microstructural evolution, hydrogen diffusion behavior and resistance to hydrogen-assisted cracking. As the quenching temperature increased from 850 °C to 1050 °C, the prior austenite grains, packets and blocks were gradually coarsened, the fraction of high-angle grain boundaries decreased from 64.7% to 54.2%, and although partial dissolution of primary carbides may occur during austenitizing, the number/area fraction and size of carbides observed in the final tempered martensitic microstructure increased after the subsequent tempering treatment. Meanwhile, the Nb/Ti-rich precipitates changed only slightly, and the dislocation density increased. The effective hydrogen diffusion coefficient, D_eff, increased with increasing quenching temperature, mainly because grain coarsening significantly reduced the high-angle grain boundary area and weakened the hydrogen-trapping effect of grain boundaries. This dominant effect masked the diffusion-retarding effects caused by increased dislocation density and coarser carbides. With increasing quenching temperature, the strength loss ratio increased from 7.3% to 12.0%, and the plasticity loss ratio increased from 10.0% to 13.6%, indicating enhanced hydrogen-assisted cracking susceptibility. The fracture morphology gradually changed from deep dimples to flat dimples and flattened ductile–brittle mixed features, while the crack propagation path became straighter. A higher quenching temperature weakened the blocking effect of grain boundaries on crack propagation and reduced the resistance of the quenched and tempered bolt steel to hydrogen-assisted cracking. Full article

The paper suggests a distributed cross-layer IoT architecture that combines LoRaWAN (Long Range Wide Area Network) with federated learning (FL) to improve reliability, scalability, and fault tolerance in multi-layer vertical farming systems in dense and dynamic environments. Unlike the traditional frameworks that rely on independent measures of QoS (Quality of Service), the proposed framework directly represents the inter-layer relationships, such as heterogeneity of latencies, robustness of connectivity, and propagation of faults. One of the contributions is the development of a cohesive cross-layer evaluation framework with six strictly defined metrics: MLDC (Multi-Layer Deployment Capacity), C-LCRI (Cross-Layer Connectivity Robustness Index), C-LFCI (Cross-Layer Fault Containment Index), SART (Smart Adaptive Recovery Time), and AIRSM (AI Resilience Score Metric), which allows for quantitatively characterizing latency differences, network resilience, fault containment, recovery efficiency, AI robustness, and energy-performance trade-offs. The experimental results show that the proposed Smart Distributed LoRaWAN–Federated Learning architecture operates reliably in high-density and multi-layer vertical farming environments, and is scalable to handle larger amounts of data. The proposed system guarantees a packet delivery ratio (PDR) of around 95% under a large-scale deployment with up to 1050 IoT nodes spread across seven cultivation layers, with a latency reduction of nearly 60%, less than 1.6 J/msg on average energy consumption, and a fault recovery time of less than 0.3 s in case of network disruptions. The proposed framework was validated using large-scale simulation scenarios developed based on experimentally reported LoRaWAN communication characteristics and agricultural IoT deployments, and operational conditions at the edge intelligence. This evaluation included up to 1050 sensing nodes in 7 vertical farming layers to approximate a realistic deployment of smart farming in a large-scale environment while keeping consistency with the recorded communication and reliability profile. Full article

Electric power systems are expanding toward higher voltage levels, larger renewable-energy bases, denser urban substations, and increasingly complex transmission corridors. These trends make inspection more frequent and more demanding, while conventional manual patrols and single-robot deployments remain constrained by safety risks, limited coverage, endurance, and fragmented situational awareness. Multi-robot systems offer a promising pathway for electric power inspection by combining heterogeneous platforms, distributed sensing, coordinated planning, and human-supervised autonomy. This review synthesizes recent progress in multi-robot inspection for power transmission lines, substations, distribution networks, and related grid assets, with particular attention to transmission corridors and substations where heterogeneous cooperation is operationally valuable. Following a Sense–Think–Act framework, we organize the literature into three interconnected components: cooperative perception for spatial and semantic understanding of grid assets; collaborative planning and task allocation for large-scale, risk-aware inspection; and coordinated execution with human oversight in safety-critical, often energized environments. We highlight how unmanned aerial vehicles (UAVs), unmanned ground vehicles (UGVs), climbing robots, and fixed robotic stations can complement one another in inspection workflows, from wide-area patrol and defect localization to close-range verification and maintenance support. We also discuss persistent challenges, including electromagnetic compatibility, reliable localization near metallic structures, multimodal data fusion, battery endurance, communication robustness, minimum approach distances, cybersecurity, benchmark scarcity, and the need for assurance mechanisms that allow operators to understand, trust, and intervene in multi-robot decisions. Finally, we outline a roadmap for moving from isolated demonstrations toward deployable, human-centered, and grid-integrated multi-robot inspection systems. Full article

Background: Colposcopy is a widely used clinical and diagnostic tool for detecting cervical intraepithelial neoplasia grade 2 or higher (CIN2+). This paper aims to analyze the diagnostic accuracy, pooled sensitivity, specificity, likelihood ratios, and overall diagnostic performance of colposcopy. Methods: A systematic review of papers on diagnostic accuracy, preregistered in PROSPERO (CRD420251028776), was conducted following PRISMA-DTA guidelines. Statistical analyses were performed using SPSS 29 and METADISC 2.0. Study quality and risk of bias were assessed using QUADAS-2. Results: A total of 49 studies, including 141,355 colposcopic examinations, were included in the final analysis. The overall sensitivity was 0.745 (95% CI: 0.684–0.797) and specificity was 0.831 (95% CI: 0.770–0.879). The diagnostic odds ratio was 14.388 (95% CI: 9.673–21.400). The positive likelihood ratio was 4.419 (95% CI: 3.260–5.991). Conversely, the negative likelihood ratio was 0.307 (95% CI: 0.249–0.378). The area under the curve was 0.8569. Significant heterogeneity was observed across studies (I² > 93.2%). Conclusions: Colposcopy demonstrates moderate-to-high diagnostic accuracy in detecting CIN2+ lesions, with a good balance between sensitivity and specificity. However, significant variability exists among studies, highlighting the need for the implementation of standardized colposcopic criteria, improved examiner training, and adjunctive diagnostic methods such as HPV testing and ancillary techniques to enhance accuracy and reduce false positives and false negatives. Future research should focus on minimizing interobserver variability and refining diagnostic algorithms to optimize colposcopic performance. Full article

Place-based fiscal transfers are widely used to promote sustainable regional development, yet their effects may vary across territories with different economic structures, fiscal capacities, infrastructure endowments, and absorptive capacity. This study examines Korea’s Special Account for Balanced Development (SABD) using panel data for 226 basic local governments. Baseline feasible generalized least squares estimates indicate a negative contemporaneous association and a positive one-year lag-effect association with per capita gross regional domestic product, with the latter substantially larger in metropolitan areas. Annual Global Moran’s I statistics reveal persistent positive clustering in local economic performance and current-year SABD, while clustering in the lag-effect measure is episodic. Fixed-effects spatial lag, spatial error, and Spatial Durbin models identify statistically significant spatial dependence, but the local current-year and lag-effect SABD coefficients become statistically insignificant. The Spatial Durbin model identifies only marginally positive indirect and total lag-effect associations, and cross-lag tests provide no evidence that the SABD lag-effect measure predicts subsequent per capita GRDP after local and year effects are controlled. The results therefore support a cautious interpretation: the baseline temporal and territorial pattern is descriptively important, but it is not sufficient to establish a causal or spatially robust local growth effect. Sustainable balanced-development finance should combine need-based allocation with local capacity building, spatial coordination, and multidimensional evaluation encompassing economic performance, demographic resilience, and public-service accessibility. Full article

Satellite chlorophyll–a (Chla) products are widely used to study coastal productivity, but their performance often degrades in river-influenced and optically complex waters. We evaluated MODIS-Aqua Chla retrievals in the coastal upwelling area off central-southern Chile, a region strongly affected by seasonal river plumes, using monthly in situ Chla and hydrographic observations from Station 18 (August 2002 to September 2011), daily MODIS products, and matchup analyses based on 3 × 3 pixel windows and 1-, 3-, 5-, and 7-day composites. MODIS Chla and normalized Fluorescence Line Height (nFLH) reproduced the broad seasonal cycle, with maxima during spring–summer, but default MODIS Chla systematically exceeded in situ observations, particularly during periods of enhanced turbidity and river-influenced optical complexity. Among the raw satellite products, 1-day MODIS Chla matchups showed the strongest agreement with in situ Chla (r = 0.77, RMSE = 8.5 mg m⁻³), whereas 5-day composites increased matchup availability to 95% but reduced the correlation (r = 0.46, RMSE = 10.5 mg m⁻³). In contrast, nFLH showed more stable performance across composite lengths, although it underestimated high Chla values and should therefore be interpreted as a complementary fluorescence-based diagnostic rather than as a direct substitute for locally validated Chla retrievals. A gradient boosting model trained with MODIS remote-sensing reflectances improved the correspondence between satellite and in situ Chla relative to the default MODIS product within the available Station 18 matchup dataset. Because this model was evaluated using cross-validation rather than an independent regional validation dataset, the machine-learning results should be interpreted as a local proof of concept rather than a fully validated regional algorithm. These results indicate that standard MODIS algorithms overestimate Chla in this river-influenced upwelling system and highlight the value of local correction approaches, including machine-learning methods, for improving coastal ocean color products, provided that future applications include independent spatially distributed validation and improved bio-optical characterization of river-influenced waters. Full article

The dried rhizome of Atractylodes lancea (RAL) is a widely used traditional Chinese medicine (TCM). Its quality evaluation and origin authentication have long relied on time-consuming chromatographic methods, which are poorly suited for rapid, on-site decisions in commercial supply chains, and existing studies generally focus on isolated morphological indicators without systematic digital characterization and practical on-site grading tools. Guided by the traditional empirical knowledge of “Bianzhuang Lunzhi”, which holds that external morphological traits can reflect the internal quality of TCM, this study presents the first systematic multi-dimensional digital characterization of RAL morphological traits using an integrated multi-sensor approach and quantitatively explores the underlying correlations between digital traits and key bioactive constituent contents. Nighty samples from three major producing regions were analyzed. Significant correlations were observed between odor indices, color parameters, density, oil cavity area ratio and bioactive component contents in the authentic Maoshan-sourced RAL (p < 0.01 or p < 0.05). Such associations were absent in the emerging regions (Dabie and Qin−Ba Mountains). A three-grade quality classification system based on density thresholds (Grade A: ≥0.73 g/cm³; B: 0.58–0.73 g/cm³; C: <0.58 g/cm³) was established specifically for Maoshan RAL. Additionally, an electronic nose-based classification model was constructed for geographical origin discrimination, which delivered reliable and robust classification performance in external validation with independent blind test samples. This work provides practical, low-cost tools for rapid quality grading and origin identification of RAL. The proposed trait-driven analytical strategy offers a generalizable framework for the quality control of other complex herbal medicines. Full article

Iterative position estimation algorithms based on Time Difference of Arrival (TDOA) are widely used in passive localization systems, including underwater acoustic networks and wireless sensor networks. A critical but often overlooked factor in their practical deployment is the selection of the initial estimate, which directly determines whether the iterative algorithm converges to the correct solution. This paper presents a case-specific approach to initial estimate selection in passive TDOA-based iterative position estimation algorithms. The study evaluates two proposed methods against a common baseline approach, where the initial guess is placed at the center of the sensor formation. Simulations were conducted in Python for both 2D and 3D scenarios, with sensors arranged in two different geometric configurations. A grid-based analysis over a 2 × 2 km area was used to assess performance under both noise-free and noisy TDOA conditions, with Gaussian-distributed error introduced at varying standard deviations. The results demonstrate that in regions where convergence is sensitive to initialization, the proposed Method 1 significantly improves reliability, especially for asymmetric sensor configurations. These findings highlight the importance of initial estimate selection to enhance position estimation accuracy and robustness, particularly in passive systems with limited prior information. Full article

High-purity synthetic quartz powders are widely used for quartz crucibles and quartzware in semiconductor processes. However, sol–gel-derived synthetic quartz powders contain hydrogen bonds on pore interiors and surfaces, inducing bubble formation during quartz glass fusion. In this study, the removal behavior of hydrogen bonds depending on calcination temperature was investigated by mass reduction, Brunauer–Emmett–Teller (BET) specific surface area, tap density, and Fourier transform infrared (FT-IR) absorbance. Physisorbed and weakly hydrogen-bonded water (~3350 cm⁻¹), vicinal/geminal silanol (~3650 cm⁻¹), and isolated silanol (~3745 cm⁻¹) were removed in the distinct temperature ranges of 200–600 °C, 700–1000 °C, and above 1100 °C, respectively. Based on this removal behavior, a stepwise calcination process at 300 °C for 5 h, 700 °C for 5 h, and 1200 °C for 10 h was designed. This process reduced OH concentration to 3.6 ppm and decreased bubble density to 0.6 bubbles cm⁻³ in fused quartz glass. Full article