Search Results (125)

In a digital watermarking technology system, robustness, imperceptibility and payload capacity are the three core performance indicators that restrict one another. How to achieve the optimal balance between the three is still the key scientific challenge to be solved in this field. This paper proposes a digital watermarking algorithm based on the magnitude coefficient of Non-Subsampled Shearlet Transform Fast and Accurate Polar Harmonic Fourier Moments (NSST-FAPHFMs) and the Weibull–Power Cauchy (W-PC) statistical model. The algorithm consists of two stages: watermark embedding and detection. In the embedding phase, the original image is first decomposed by NSST multi-scale decomposition, and the high-frequency subbands are divided into non-overlapping blocks and partitioned. High-energy coefficient blocks are extracted to obtain NSST-FAPHFM magnitude coefficient features, which serve as robust carriers for watermark embedding. In the detection phase, the W-PC distribution is used to accurately statistically model the above magnitude coefficients to characterize their heavy-tailed characteristics and strong correlation structure. Maximum likelihood estimation (MLE) is employed to estimate the model parameters, and a blind watermark detection mechanism is further constructed by integrating the W-PC model with the Local Optimal Detector (LOD) under the Neyman–Pearson (N-P) criterion. Experimental results show that the proposed algorithm has good imperceptibility, and the area under the receiver operating characteristic curve (AUROC) can reach 0.9991 without attack. The algorithm maintains strong robustness against various attacks and can effectively realize the joint optimization of the three core performance indicators of the watermarking system. Full article

Accurate crop mapping in middle-to-high latitude agricultural basins is essential for food security, agricultural management, and sustainable land-use planning. However, crop classification in these regions remains challenging because fragmented field patterns, mixed pixels, and overlapping phenological stages often lead to severe spectral confusion among major dryland crops. To address this issue, this study developed a Phenology–Spectral Dual-Constrained Strategy (PS-DCS) by integrating agronomic knowledge with physically constrained spectral features. The proposed framework identified August as the optimal observation window based on crop phenological divergence. Wheat was first extracted using a spectral fingerprint combining the Chlorophyll Index Red Edge (CI_RE) and Redness index. Subsequently, maize and soybean were separated within the non-wheat mask using the B6 red-edge band selected through feature separability analysis. Validation based on Sentinel-2 time-series imagery and 1056 independent field samples collected in 2025 yielded an Overall Accuracy of 95.36% with a Kappa coefficient of 0.928. Compared with RF, XGBoost, and CNN models, PS-DCS maintained competitive classification performance while substantially reducing dependence on large training datasets and complex parameter tuning. Cross-year validation during 2022–2024 further demonstrated stable spatial transferability without threshold recalibration. These results indicate that translating agronomic mechanisms into physically interpretable remote sensing rules provides an effective and transparent framework for high-precision crop mapping and long-term agricultural monitoring in complex agricultural landscapes. Full article

Background: Processed extracellular lipid–protein preparations require rigorous analytical characterization to determine whether their compositional profile, processing stability, and short-term cellular compatibility are preserved across storage and handling conditions. Methods: In this study, we quantitatively characterized a processed phospholipoproteic secretome-derived formulation under fresh, concentrated, cryopreserved, and lyophilized conditions. Results: Label-free quantitative proteomic analyses performed using timsTOF Pro mass spectrometry coupled to dia-PASEF acquisition identified 574 human proteins across all experimental conditions following predefined analytical quality criteria. Comparative analyses demonstrated preservation of the overall structural proteomic profile following processing and storage procedures, with retention of membrane-associated and extracellular structural proteins consistently exceeding 90% relative to the fresh reference condition. Quantitative reproducibility remained high across all experimental groups, with coefficients of variation ranging from 3.0% to 4.5% and strong inter-replicate Pearson correlations. Principal component analysis, hierarchical clustering, peptide/protein overlap analyses, and differential expression profiling demonstrated limited proteomic divergence while preserving the majority of quantified proteins within conserved abundance ranges. Complementary real-time live-cell kinetic imaging performed in non-malignant dermal-derived cells using the IncuCyte^® S3 platform demonstrated stable short-term confluence kinetics and cellular viability exceeding 92% over 48 h across all evaluated formulations. No sustained proliferative suppression or detectable morphological evidence of cytotoxicity was observed. Collectively, these findings support the preservation of compositional stability, analytical reproducibility, and short-term ex vivo cellular compatibility across defined processing and storage conditions. These integrated proteomic and kinetic datasets provide a quantitative framework for the analytical evaluation of processed extracellular phospholipoproteic preparations, while functional barrier activity, membrane incorporation, lipid raft engagement, and long-term tissue-level effects remain to be addressed in dedicated future studies. Full article

The purpose of this study is to characterize, through an exploratory empirical diagnosis, the degree of development and preliminary association between circular economy capabilities and sustainability-oriented digital transformation capabilities in Chamber-affiliated SMEs in Lambayeque, Peru. Guided by three exploratory working hypotheses, the study expected intermediate levels of development, heterogeneous performance across dimensions, and a positive but non-confirmatory coupling between both capability families. A self-administered questionnaire with thirty Likert-type items measured four circular economy dimensions—circular design and eco-design, resource optimization, circular waste management, and circular business models—and four sustainability-oriented digital transformation dimensions—digital technology infrastructure, dynamic digital capabilities, sustainable digital strategy, and digital innovation culture. The initial database contained 111 complete Chamber-affiliated responses; however, seven large Chamber-affiliated firms were retained only as contextual comparators and were excluded from all statistical processing. Consequently, all descriptive, psychometric, and SEM results were calculated using the final analytical sample of 104 micro-, small-, and medium-sized enterprises. The findings show intermediate development in both constructs, higher perceived performance in digital innovation culture and resource optimization, and lower performance in digital technology infrastructure, reverse logistics, platforms enabling circularity, and monetization of circular models. The latent association between the two higher-order constructs was very high (β = 0.985, p < 0.001); however, because global fit indices were below conventional thresholds, this coefficient is interpreted as preliminary evidence of empirical overlap and capability co-occurrence rather than confirmatory evidence of a validated structural model or causal integration. Full article

Background: Routine use of the chorioallantoic membrane (CAM) tumor model in nuclear imaging studies is hampered by small tumors, embryonic movements and laborious volume-restricted intravenous tracer/drug administration. We sought a workaround by using fast-growing tumors, high-resolution autoradiography and non-intravenous tracer administration. Methods: Dekalb White chicken eggs were grafted with C3H mammary carcinoma fragments or MOC2 oral squamous cell carcinoma fragments from donor mice. The tumor uptake of ¹⁸F-fluorodeoxyglucose (FDG) following in-yolk-sac injection, dripping after CAM scoring or allantoic cavity injection was evaluated using positron emission tomography (PET) and autoradiography. Using in-yolk-sac injection, eggs were administered different tracer mixtures, namely (1) pimonidazole (hypoxia-marker), FDG and ¹⁴C-2-deoxyglucose (¹⁴C-2DG), (2) pimonidazole, FDG and ¹⁴C-acetate or (3) pimonidazole, the hypoxia-selective tracer ¹⁸F-fluoroazomycin-arabinoside (FAZA) and ¹⁴C-2DG. For comparison, tumor-bearing mice were administered FDG/¹⁴C-acetate/pimonidazole. Gross tumor uptake was evaluated using PET. Tumor cryosections were analyzed using dual-tracer autoradiography. Complementary autoradiograms were co-registered, covered by a square grid (0.5 × 0.5 mm). Pearson correlation coefficients (PCC) were calculated from scatterplots. Results: C3H tumors reached a mean weight (with 95% confidence interval) of 0.32 g (0.28–0.37 g), while for MOC2, it was 0.19 g (0.09–0.29 g). In-yolk-sac tracer injection was simple and effective, producing high tracer uptake and contrast 3 h post-administration. Spatial tracer overlap (PCC) was: FDG vs. ¹⁴C-2DG, 0.95–0.97; FAZA vs. ¹⁴C-2DG, 0.71–0.79 and FDG vs. ¹⁴C-acetate, 0.26–0.84 (0.15–0.76 in mice). Pimonidazole revealed tumor hypoxia. Conclusions: Direct-grafting from donor mice generated larger tumors than previously reported. In-yolk-sac tracer administration was practical and allowed larger injected volumes. Autoradiography revealed that: (1) FDG and ¹⁴C-2DG can be used interchangeably, (2) ¹⁴C-2DG was elevated in FAZA-positive areas, suggesting that in some tumors FDG-PET may provide information on the intratumoral distribution of hypoxic areas, and (3) FDG and ¹⁴C-acetate showed variable overlap. We conclude that in-yolk-sac tracer injection and autoradiography simplify and optimize CAM-based nuclear imaging research. Full article

Despite the growing use of acceleration–speed (AS) profiling in elite football, the number and composition of sessions required to generate stable in situ profiles remain unclear. AS profiling provides estimates of maximal theoretical acceleration (A0) and maximal theoretical velocity (S0), which may offer practically relevant information for monitoring player sprint-related qualities. This study examined the influence of profiling-window length and match exposure on in situ AS profile outcomes in 19 professional football players competing in the 2023–2024 English Football League Championship. Profiles were generated using two non-overlapping conditions comprising five consecutive sessions (5SS) and ten consecutive sessions (10SS). Mean A0 values were 6.91 ± 0.36 m/s² for 5SS and 7.12 ± 0.40 m/s² for 10SS, while mean S0 values were 9.52 ± 0.29 m/s and 9.89 ± 0.28 m/s, respectively. Reliability was assessed using intraclass correlation coefficients (ICCs), standard error of measurement (SEM), and smallest worthwhile change (SWC). The match count within each profiling window was associated with A0 and S0 outcomes in both 5SS and 10SS conditions (all p ≤ 0.004). However, ICC values were low, particularly for S0, and SEM exceeded SWC across conditions, indicating limited sensitivity for detecting small meaningful changes. These findings suggest that longer profiling windows may provide slightly more stable A0 estimates, whereas S0 appears more sensitive to match exposure and contextual variability. The results highlight the importance of interpreting AS profiles at an individual level and accounting for match exposure when comparing profile outcomes across monitoring windows. Full article

To accurately characterize the effects of polydisperse particle sizes, multimineral composition, and angular morphology on the packing structure of lunar regolith, a two-dimensional sequential packing method based on random convex octagons is proposed. The method establishes a particle parameter system using data from Chang’e-5 samples and generates polygonal particle models with controllable angular features through radial perturbation. On this basis, a sequential packing algorithm based on available arc analysis is developed. Non-overlapping particle insertion is achieved via geometric envelope constraints, and progressive filling is realized through effective arc sampling. Meanwhile, a packing control coefficient is introduced to enable continuous regulation of packing density. Results show that the proposed method can generate highly dense particle assemblies, with a maximum packing density of 0.8757 and an average coordination number of approximately 3.18, capturing the structural characteristics of “high compactness–low coordination number” in polydisperse angular particle systems. The algorithm exhibits a computational complexity of O(N^1.628), demonstrating high efficiency. Furthermore, contact area and contact strength are quantitatively characterized through contact contour extraction and an equivalent bow-shaped model. Radial distribution function and contact statistics indicate that the generated structures possess good randomness and physical consistency. The proposed method provides a high-fidelity mesoscopic structure generation approach for discrete element modeling (DEM) of lunar regolith and establishes a reliable foundation for analyzing the mechanical behavior of granular systems. Full article

The aim of this study was to quantify the effects of implement type, field condition, and gear stage on tractor traction performance under representative field operating conditions using full-scale field-measured data. Field experiments were conducted in five fields using a 78-kW agricultural tractor equipped with a moldboard plow, chisel plow, and subsoiler, and traction performance was evaluated based on the tractive coefficient (TC) and tractive efficiency (TE), both computed from directly measured drawbar pull and axle power. An effect size (η²) analysis revealed a clear and consistent hierarchy among the three factors: field condition was dominant (η² = 91.6% for TC and 88.2% for TE), followed by implement type (67.8% for TC but only 11.3% for TE), whereas gear stage was minor (≤5.9%). TC and TE were highest in the firm loam field and lowest in the wet loamy sand field, with clearly separated, non-overlapping distributions across fields. The pronounced TC–TE asymmetry of implement type shows that the two indicators capture complementary aspects of traction and must be evaluated jointly. Measured TC distributions were broadly consistent with soil texture and moisture-based net TC reference bands, and the measured TE values deviated from the ASAE D497.4 reference values depending on the soil texture and moisture content, demonstrating that traction performance can vary substantially even within the same soil texture class. These results indicate that soil texture, moisture content, and cone index must be considered jointly when evaluating tractor traction performance, and are expected to contribute to tractor design optimization and the establishment of field condition-based work management standards. Full article

Multiparametric magnetic resonance imaging (mpMRI) is the standard imaging modality for the detection and evaluation of prostate cancer (PCa); however, diagnostic challenges remain due to overlapping imaging features of malignant and benign tissue. The healthy prostate is approximately reflectionally symmetric, whereas malignant transformation introduces structural asymmetry. A novel algorithm that exploits this asymmetry to detect PCa on T2-weighted (T2W), diffusion weighted (DWI), and apparent diffusion coefficient (ADC) images is presented. This study represents a proof-of-concept evaluation of a symmetry-based, training-free approach. Asymmetry features are extracted across all three sequences using band-pass filtering, adaptive thresholding, and intensity-based criteria, and fused into a unified detection map. The method was evaluated in 66 men with histopathological confirmation (33 biopsy-confirmed PCa cases and 33 biopsy-negative controls). The algorithm correctly detected cancer in 29 of 33 cases (sensitivity 87.9%) and correctly classified 15 of 33 non-cancer cases, yielding a specificity of 45.5% and an overall accuracy of 66.7%. Detection performance was higher for lesions ≥ 10 mm (sensitivity 91.7%) than for lesions < 10 mm (sensitivity 77.8%). The PcaAsym framework demonstrated complete intra-reader reproducibility and substantial inter-reader agreement. These results demonstrate the feasibility of symmetry-based analysis as an interpretable and deterministic approach for PCa detection. Validation in larger, consecutive cohorts is warranted to assess performance in routine clinical settings. Full article

Millimeter-wave radar enables non-contact monitoring of cardiac activity and therefore has the potential to reconstruct electrocardiogram signals without surface electrodes. However, existing radar-based electrocardiogram reconstruction methods still suffer from incomplete extraction of heartbeat-related information and insufficient modeling of electrocardiogram-related features, which limits reconstruction accuracy. To address these issues, this study proposes a millimeter-wave radar-based electrocardiogram reconstruction method that integrates a respiratory-harmonic-suppressed multi-channel signal-processing frontend with the proposed CA-WTBNet deep reconstruction network. First, based on maximal overlap discrete wavelet transform-based multi-resolution analysis, respiratory harmonics mixed into heartbeat-related components are suppressed by combining respiratory harmonic detection with a heart-rate frequency protection strategy, while cardiac-related information is preserved as much as possible. A multi-channel input representation is then constructed. Meanwhile, the proposed deep reconstruction network is developed to jointly model complementary channel-wise features, local waveform morphology, and temporal dependencies by integrating channel-attention mechanisms, convolutional residual modules, window-based Transformer blocks, and bidirectional long short-term memory. Experiments conducted on the public dataset show that our method achieves an average Pearson correlation coefficient of 0.9641, a mean normalized root mean square error of 0.0458, an average R-peak F1 score of 0.9956, and an average R-peak timing error of 3.13 ms on the test set. In comparison with related studies on the same public Resting dataset, the proposed method achieves the best overall performance among the compared methods, with a 0.53% improvement in Pearson correlation coefficient and a 10.20% reduction in normalized root mean square error over the best-performing compared method. Full article

Niche and interspecific association are important components of community ecology and are of great significance for revealing the mechanisms of community assembly and its stability. In this study, the woody plant communities of Betula platyphylla Sukaczev forests in the Niyang River Basin of southeastern Qinghai–Tibet Plateau were taken as the research object. The niche, interspecific association, and community stability of dominant tree species in B. platyphylla forests were analyzed using the Levins index (B_L), Shannon index (B_S), Pianka index (O_ik), Schoener index (C_ik), variance ratio (VR), chi-square test, association coefficient (AC), Spearman rank correlation, and M. Godron stability methods. The results showed that a total of 71 woody plant species were recorded across 48 plots, mainly belonging to Rosaceae, Ericaceae, and Caprifoliaceae. B. platyphylla, Quercus aquifolioides Rehder & E. H. Wilson, Sorbus rehderiana Koehne, and Berberis gyalaica Ahrendt had relatively large niche breadths, indicating strong resource utilization ability and a wide range of spatial adaptation. They were the main constructive species and dominant species of B. platyphylla forest communities in this basin. The overall niche overlap of woody plant communities was relatively low, indicating relatively obvious differentiation in resource utilization among different species. Interspecific association analysis showed that the dominant species in the tree layer exhibited an overall significantly positive association, whereas those in the shrub layer exhibited an overall non-significantly positive association. The associations between species pairs were mainly non-significant, and the overall interspecific association was weak. Most species showed a relatively independent distribution pattern, reflecting weak interspecific competition within the community. Community stability analysis showed that the Euclidean distance between the tree layer and the theoretical stability point (20, 80) was 20.17, whereas that of the shrub layer was 27.98, indicating that the tree layer was more stable than the shrub layer. Overall, the community may not yet have reached a fully stable state. The results provide important references for biodiversity conservation, vegetation restoration, and sustainable forest management in alpine canyon ecosystems. Future studies should incorporate environmental factors such as soil properties and hydrothermal conditions to further reveal the ecological mechanisms driving community succession and stability. Full article

Background: Acute focal neurological deficits require rapid differentiation between ischemic stroke and stroke mimics to avoid treatment delays and inappropriate therapy. Seizures, including ictal deficits, status epilepticus, and post-ictal/Todd’s phenomena, are among the most challenging mimics. This review summarizes the role of multimodal neuroimaging in distinguishing acute ischemic stroke from seizure-related deficits. Methods: We performed a focused narrative review of neuroimaging findings in acute stroke mimics, emphasizing non-contrast computed tomography (CT), CT angiography, CT perfusion, magnetic resonance imaging (MRI), including diffusion weighted imaging (DWI), apparent diffusion coefficient (ADC), fluid attenuated inversion recovery (FLAIR), and arterial spin labeling (ASL) sequences. Imaging patterns, diagnostic pitfalls, and practical clues for hyperacute stroke pathways were synthesized. Results: Acute ischemic stroke is typically suggested by vascular-territorial abnormalities, including arterial occlusion or stenosis, territorial hypoperfusion, and congruent DWI/ADC restriction. Seizure-related deficits more often show non-territorial cortical perfusion changes, ictal or status-related hyperperfusion, reversible MRI abnormalities, and absence of arterial occlusion. However, post-ictal hypoperfusion, peri-ictal diffusion restriction, and reperfusion-related hyperperfusion may overlap with ischemic patterns. Conclusions: A multimodal approach integrating vascular imaging, perfusion distribution, DWI/ADC, ASL, clinical timing, and EEG findings can improve diagnostic accuracy in the stroke–seizure differential without delaying treatment in true acute ischemic stroke. Full article

Electroencephalography (EEG) is a non-invasive technique used to monitor brain activity but is prone to physiological artifacts, especially eye movements (EOG) and muscle contractions (EMG). These artifacts are non-stationary and frequently overlap with neural oscillation bands, making them difficult to separate accurately from genuine EEG activity. Conventional single-domain filters often fail to eliminate such interference, resulting in either residual noise or the unintended suppression of authentic EEG data. To address these limitations, we propose a Frequency-Aware Residual U-Net (FARU-Net), a dual-domain, frequency-aware residual architecture for EEG artifact removal designed to improve restoration fidelity. Unlike models based solely on temporal features, FARU-Net explicitly modulates the spectral properties of the signal in the latent space through a Frequency-aware Bottleneck Module (FBM), while simultaneously refining temporal details. Additionally, Attention Gates (AGs) are integrated into the skip connections to refine feature fusion and reduce residual noise while preserving salient waveform structures. Comparative experiments on the EEGdenoiseNet benchmark demonstrate that FARU-Net achieves strong overall performance for single-channel EEG restoration. Across five independent test groups, the proposed model attains a mean Pearson correlation coefficient (CC) of 0.9681 and a mean signal-to-noise ratio improvement (ΔSNR) of 26.66 dB. These results indicate that the proposed method effectively preserves both waveform morphology and spectral structure compared with conventional U-Net variants and CNN-based models. Full article

Wireless links in underground coal mines suffer from severe attenuation, blockage, and limited spatial coverage. To improve link quality under these conditions, we study a simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS)-assisted system with multiple movable antennas (MAs) installed at the base station (BS) panel. Unlike prior models that assume a continuous movement box, we explicitly account for practical panel constraints: mechanical supports and RF feed lines partition the BS panel into non-overlapping irregular feasible subregions. This turns the BS-side antenna-positioning task into a mixed-integer nonlinear program (MINLP). We formulate a joint optimization problem that couples BS beamforming, STAR-RIS transmission/reflection coefficients, BS-side MA positions, and MA-to-subregion assignment with collision-avoidance constraints. To solve it, we adopt a block coordinate descent (BCD) framework: successive convex approximation (SCA) for beamforming, semidefinite relaxation (SDR)-based updates for STAR-RIS coefficients, and a penalty-based continuous relaxation for MINLP handling. The MA solver further integrates Hungarian initialization, cross-region jump updates, and reassignment corrections to escape poor local subregions. Simulation results in coal mine channel settings show that the proposed method yields a 66.7% sum-rate gain over fixed-antenna baselines and reduces required transmit power by 16.8 dB at the target-rate operating point. Compared with a regular-region BS-MA baseline, the irregular-partition design achieves an additional 5.6 dB power saving, demonstrating the practical value of hardware-aware geometry modeling. Full article

Achieving net-zero emissions requires balancing decarbonization with sustained enterprise development. Using panel data on China’s A-share listed firms from 2011 to 2023, this study examines whether regional carbon emission trading rights (CETR) pilots promote enterprise upgrading, proxied by the New Quality Productive Forces (NQPF) index. A staggered multi-period difference-in-differences framework shows that the CETR policy significantly increases enterprise NQPF (coefficient 0.059, p < 0.05). This finding remains robust after parallel trend tests, placebo simulations, propensity score matching, controlling for overlapping environmental policies, and using alternative outcome measures. Channel analyses indicate that CETR affects NQPF through two pathways: easing financing constraints (coefficient −0.019, p < 0.01) and accelerating digital transformation (coefficient 0.102, p < 0.01). The positive policy effect is stronger among non-state-owned enterprises and among firms whose senior managers lack financial backgrounds or do not hold concurrent positions in shareholder units. These results demonstrate that carbon trading drives systemic enterprise upgrading via resource and technology channels, with important heterogeneity across ownership and governance structures. Full article