Search Results (289)

Slow-time coding techniques, including Code Division Multiple Access (CDMA), Doppler Division Multiple Access (DDMA), and joint CDMA–DDMA coding, are widely used in Multiple-Input Multiple-Output (MIMO) millimeter-wave radar systems to improve transmit-channel isolation, angular resolution, and field of view (FOV). However, traffic radar applications also require a high range resolution and long unambiguous detection range, which cannot be fully achieved by MIMO coding alone. This paper proposes a stepped-frequency Doppler-coded integrated joint division multiple access (SF-DC-JDMA) waveform that embeds stepped-frequency (SF) modulation into a jointly encoded CDMA–DDMA MIMO framework. In the proposed design, inter-group CDMA coding provides group-level transmit separation, intra-group DDMA modulation supports Doppler-domain Tx identification, and stepped-frequency synthesis improves range resolution. The resulting waveform combines multi-Tx orthogonality with synthesized wide-band ranging, enabling simultaneous channel separation, high-resolution range estimation, and long-range detection. The simulations and real-scene measurements demonstrate that, under the same range coverage, the proposed SF-DC-JDMA waveform achieves a significantly improved range resolution relative to the conventional FMCW waveform integrated by CDMA and DDMA modulation, and yields denser point-cloud representations of traffic targets. Full article

The combination of Suzuki arylation and Buchwald–Hartwig amination provides a sequentially Pd-catalyzed pseudo-four-component strategy for the synthesis of symmetrically substituted 3,7,10-triarylphenothiazines in moderate to good yields. Using p-anisyl-derived donor units and p-benzonitrile-derived acceptor units, the electronic and photophysical properties of four representative derivatives were investigated by cyclic voltammetry, absorption and emission spectroscopy, and (TD-)DFT calculations. The calculated electronic transitions are in good agreement with the experimental absorption spectra and enable assignment of the underlying optical transitions, while the observed photophysical behavior is interpreted in the context of previous studies on related 3,10-diarylphenothiazines. A p-anisyl donor substituent at the phenothiazine nitrogen atom favors the intra-oriented ground-state conformation, resulting in intense low-energy absorption bands and high fluorescence quantum yields. In contrast, a p-benzonitrile substituent at this position shifts the conformational equilibrium toward the extra-oriented conformation, leading to altered electronic transitions and reduced fluorescence efficiency. Combined with p-anisyl donor units at the 3,7-positions, the extra-oriented conformation becomes predominant, resulting in pronounced emission quenching. These findings demonstrate that 3,7,10-triarylphenothiazines represent a class of redox-active luminophores in which electronic substitution and conformational preferences provide complementary handles for tuning ground- and excited-state properties. Full article

Background/Objectives: In this study, a novel reversed-phase high-performance liquid chromatography (RP-HPLC) method was established for the quality control of amiodarone hydrochloride, overcoming the limitations of the legacy compendial protocol. The conventional United States Pharmacopeia method requires a 10-fold sample dilution to avoid column overload and matrix interference from polysorbate 80. Attempting direct injection under conventional conditions severely compromises data reliability, leading to severe band broadening and peak distortion. Methods: To fairly evaluate the intrinsic separation capacity of the analytical systems, preliminary experiments were conducted using identical, undiluted dissolution samples. Through precise chromatographic redesign, the novel method eliminates the pre-treatment dilution step. Furthermore, the reliability, precision, and robustness of the proposed method were comprehensively validated in strict accordance with the International Council for Harmonisation Q2 guidelines. Results: Even upon direct injection of highly concentrated samples, the optimized system focuses broad peaks into sharp, symmetric, and narrow bands, increasing analytical sensitivity and theoretical plates. Furthermore, it maximizes intra-column separation efficiency, achieving complete baseline isolation of amiodarone from surfactant interferences within a retention time of approximately 6.6 min, thereby significantly improving analytical throughput. Conclusions: By eliminating cumbersome sample preparation, minimizing analysis time, and enhancing quantitative integrity, this validated RP-HPLC method offers an efficient, high-throughput standard analytical platform. It is highly suitable for rapid routine quality control and high-precision dissolution testing of generic amiodarone pharmaceuticals in industrial settings. Full article

Youth football academies increasingly utilize physical testing, athlete monitoring, anthropometric profiling, and performance analysis to support athlete development and training management. During adolescence, rapid biological maturation, fluctuating neuromuscular coordination, variable recovery capacity, and ongoing psychological development may substantially influence physical and football-specific performance over time. Consequently, athlete-management decisions based exclusively on isolated testing outcomes may inadequately reflect the developmental needs of young players. This narrative review presents a developmentally informed framework for applied athlete management in youth football academies. The review discusses the interaction between football-specific technical and tactical qualities, physical performance characteristics, biological maturation, somatometric profile, psychological and perceptual-cognitive factors, recovery management, and monitoring strategies during adolescent development. Particular emphasis is placed on practical implementation within real-world academy environments, including low-cost monitoring approaches, intra-club bio-banding, multidisciplinary communication, and athlete-specific intervention planning. Overall, the proposed framework positions athlete monitoring as a continuous support process designed to guide training adjustment, recovery management, and sustainable football progression within youth football development pathways. Full article

Clear aligners can be carriers of bleaching agents as pretreatment before orthodontic and prosthodontic treatment and therefore are exposed to the influence of the oral cavity and oxidizing agent. In this research, the effects of 14 days’ intra-aligner bleaching with 10% carbamide peroxide during clinical treatment on the thermomechanical behavior and infrared fingerprint of Nuvola^® aligners were assessed. Five experimental groups were tested (six DMA specimens in each group): control (not used), 14 days wear without bleaching, and 14 days wear with bleaching for 3, 7, and 14 days. The onset glass transition temperature (Tg) was determined by dynamic mechanical analysis, and Fourier-transform infrared spectroscopy (FTIR) was applied for qualitative evaluation of the chemical fingerprint of PETG. Statistically higher Tg was found in bleached groups than in the control and wear-only groups, although the values differed only between 78.35 and 79.23 °C. No trend of changes depending on exposure duration was found. There were no shifts in FTIR peaks, no additional bands appeared, and no characteristic bands disappeared. Thus, bleaching caused a statistically significant but small Tg increase and did not alter the infrared fingerprint of PETG. Low-level chemical modification below the sensitivity of qualitative FTIR cannot be excluded. Full article

Farm field units are the fundamental management units of modern precision agriculture, and accurate identification of their geographic boundaries is essential for the data management of farmland soil and nutrients. However, traditional manual vectorization methods are inefficient and costly. To address this issue, this study proposes an automated farm field unit identification framework based on remote sensing image segmentation and parameter optimization. Starting from the framework of Geographic Object-Based Image Analysis (GEOBIA), the framework employs the multiresolution segmentation (MRS) algorithm combined with intra-segment homogeneity and inter-segment heterogeneity indicators, and iteratively determines the optimal scale parameters through three unsupervised segmentation parameter optimization (USPO) methods, namely the methods proposed by Espindola et al. (EUSPO), Zhang et al. (ZUSPO), and Johnson et al. (JUSPO), to achieve automatic identification of farm field information. The framework was evaluated on eleven production teams of the Tenihe Farm, a large-scale intensive farm in Hulunbuir, China, using two scenes of Landsat 8 OLI imagery acquired on 18 September 2019 (multispectral bands pan-sharpened to 15 m, with the red, green, blue, and near-infrared bands used for segmentation), taking field-investigation-verified farm field vector maps as the reference. The results show that the identification accuracy of farm field units generally reaches over 80%. The main contribution of this study lies in extending USPO methods from segmentation quality evaluation to automated farm field vector extraction in precision agriculture, and in providing a systematic horizontal comparison of three USPO combination strategies under large-scale heterogeneous agricultural landscapes, which reveals that the JUSPO method, with its F-measure fusion strategy, achieves the most robust performance in most teams. These findings verify the effectiveness and application potential of the proposed framework. Full article

Identifying rolling bearing faults under few-shot conditions remains difficult because fault samples are scarce, class-space distributions are unstable, and inter-class boundaries may become ambiguous. This paper proposes a fault diagnosis model based on the Multi-Aspect Geometric Structure Learning and Discrimination Framework (MAGS-LDF). First, one-dimensional vibration signals are mapped into three two-dimensional representations, namely angle field (AF), band-energy (BE), and time-frequency (TF) images, to describe fault information from temporal correlation, frequency–band energy distribution, and time-frequency response perspectives. Second, a dual-branch feature extraction network is designed to extract fusion features and channel features. For each fault class, channel features are aggregated into channel centers, which are further fused to obtain a public center. Moreover, regular polytope anchor centers aligned with the public-center distribution are introduced to impose geometric constraints, encouraging intra-class compactness and inter-class separation. Finally, channel distances and public distances are jointly used to construct a multi-scale distance discrimination mechanism for few-shot fault classification. Experiments on CWRU and SEU show that MAGS-LDF outperforms the best comparison method by 2.34%, 5.37%, and 5.34% on CWRU and by 3.55%, 5.10%, and 3.46% on SEU under the three-shot, five-shot, and 10-shot settings, respectively. Full article

Upstream–downstream nutrient connectivity strongly regulates water-quality risk in reservoir cascades, yet its quantification remains difficult where discharge, reservoir release, and hydraulic residence-time records are unavailable. This study developed a causal–explainable framework to diagnose total nitrogen (TN) connectivity between the upstream Shimantan Reservoir and downstream Banqiao Reservoir in the Huai River Basin, China. Long-term water-quality records, meteorological variables, land-cover indicators, seasonal descriptors, and lagged upstream predictors were integrated within a leakage-safe analytical workflow combining nonlinear causal inference, time–frequency coupling diagnostics, predictive modeling, SHAP-based attribution, and counterfactual analysis. Convergent Cross Mapping identified statistically significant asymmetric bidirectional nonlinear coupling, with a CCM skill of ρ = 0.746 for Shimantan TN → Banqiao TN and p = 0.730 for the reverse direction (p = 0.002 for both directions). Wavelet coherence showed that upstream–downstream TN coupling was concentrated mainly at short temporal scales, with a cone-of-influence-restricted mean squared coherence of 0.7114 in the 2–6-month intra-seasonal band. The validation-selected Gradient Boosting model provided interpretable test-period predictive skill, on independent source-derived observations from 2021–2023, achieving R² = 0.567, RMSE = 0.391 mg/L, and MAE = 0.312 mg/L. The GAN-generated 2024–2025 segment was excluded from empirical model evaluation and retained only for exploratory future-scenario assessment. SHAP decomposition indicated that upstream-related predictors accounted for 77.04% of the total absolute model attribution during high-TN events, while seasonal conditioned counterfactual upstream neutralization produced mean model-predicted changes of 0.162 mg/L across all test observations and 0.807 mg/L during high-TN events. Together, these results demonstrate that hidden upstream-downstream TN connectivity can be diagnosed through convergent causal, temporal, predictive, and model-attribution evidence in data-limited reservoir cascades. The findings support asymmetric coupled dynamics and downstream inheritance of upstream information but should not be interpreted as proof of exclusively one-way physical nutrient transport. The proposed framework offers a diagnostic decision-support approach for reservoir systems with sufficiently long monitoring records where direct hydraulic observations are unavailable. Full article

As data-center interconnects move to co-packaged optics (CPO), high-power application-specific integrated circuits (ASICs) and heat-sensitive optical engines share a single interposer, and the resulting intra-module thermal coupling overwhelms conventional schedulers. Thermal-aware microservice directed acyclic graph (DAG) scheduling on CPO modules is recast here as a question of symmetry. Whereas a homogeneous-graph policy assumes the full node-permutation symmetry, that symmetry is broken twice: by the distinct task and processor node types, and by the asymmetric ASIC–engine coupling. We therefore propose a heterogeneous-graph Proximal Policy Optimization (PPO) scheduler in which the placement head is permutation-equivariant, the delay head is permutation-invariant, and the parameterization stays invariant to the processor count N. Because these symmetries hold by construction, the policy transfers zero-shot across module sizes. Heterogeneous edge typing and the resistor–capacitor (RC) coupling edge attribute are isolated by a six-test ablation chain. Evaluated on the Alibaba 2021 microservice trace across all module sizes and ambient regimes under the standard auto-cool budget, the proposed scheduler cuts the thermal-violation rate from roughly $98\%$ under the Heterogeneous Earliest-Finish-Time (HEFT) heuristic to about $0.3\%$; at the hot operating point it lowers peak temperature by about $25\%$ and raises DAG completion from about $26\%$ to $100\%$, with the rare residual violations most frequent in the extreme-ambient band. With the env auto-cool budget disabled, a controlled single-axis comparison shows that removing the RC-coupling edge attribute raises the violation rate by over an order of magnitude, isolating its contribution. A single parameter set serves every N without retraining. Full article

Lichen planus pigmentosus inversus (LIPPI) is a rare variant within the spectrum of lichenoid dermatoses, characterized by sharply demarcated hyperpigmented lesions predominantly affecting intertriginous areas. Its pathogenesis remains incompletely understood, but immune-mediated mechanisms triggered by exogenous factors have been proposed. We report the case of an 80-year-old Caucasian female who developed extensive, reticulated brownish-grey hyperpigmentation involving multiple flexural sites shortly after the fifth intra-articular injection of the homeopathic combination preparation Zeel comp. N for knee pain. Histopathological examination showed a markedly atrophic epidermis with compact orthokeratosis, focal hypergranulosis, basal vacuolar/interface change, pigment incontinence, and a band-like lymphocytic infiltrate; these findings were compatible with LIPPI. The temporal association with repeated intra-articular administration of botanical and sulfur-containing compounds suggests a possible trigger; however, causality remains speculative. Prick and patch testing with the injection solution were negative, no rechallenge was performed, and pharmacovigilance assessment by the Naranjo algorithm supported only a possible adverse drug reaction. Several constituents, including Toxicodendron derivatives, Arnica montana and Solanum dulcamara, are recognized sensitizers capable of inducing delayed-type immune responses. Importantly, allergic contact sensitization and lichenoid interface dermatitis are distinct processes; in the present case, sensitization or systemic immune stimulation is considered only as a potential upstream trigger of a lichenoid reaction pattern. Similar lichenoid eruptions, including LIPPI, have been reported after systemic immune stimulation such as COVID-19 vaccination or targeted therapies. Differential diagnoses, particularly ashy dermatosis, were considered less likely because of the inverse/flexural distribution and clinico-pathological evidence of lichenoid interface dermatitis with epidermal atrophy. Treatment with systemic corticosteroids, acitretin, and topical tacrolimus improved pruritus, whereas hyperpigmentation persisted. This case highlights a possible temporal association between intra-articular administration of biologically active compounds and LIPPI, while emphasizing the need for cautious interpretation, pharmacovigilance data, and further reports. Full article

Background: Autism spectrum disorder (ASD) is characterized by widespread aberrations in brain scalp-level synchronization. Phase-amplitude coupling (PAC), which reflects cross-frequency neuronal oscillatory interactions, serves as a crucial metric for assessing functional brain integration. However, the specific patterns of PAC at both intra-region and inter-region scalp levels in young children with ASD, as well as their precise associations with clinical symptoms, remain unclear. Methods: This study enrolled 237 children with ASD aged 3–9 years and 201 age-matched typically developing (TD) children. Resting-state electroencephalography (EEG) data were acquired from all participants. The analysis systematically examined low-frequency oscillation phase (δ, θ, α) modulation of high-frequency oscillation amplitude (β and low γ) from both intra-region and inter-region dimensions. The PAC strength was quantified using the modulation index (MI). Multiple comparisons were corrected using the Bonferroni method. Finally, correlations between PAC metrics and Autism Behavior Checklist (ABC) scores were analyzed. Results: Compared to the control group, children with ASD exhibited significant frequency-specific PAC abnormalities: (1) Multi-regional γ hyper-coupling: There was a significant enhancement in the modulation of γ amplitude by δ/θ/α phase across the measured scalp regions, suggesting abnormal high-frequency synchronization. (2) Dissociated β modulation patterns: The ASD group showed increased δ–β coupling (predominantly in frontal, temporal, and occipital lobes) alongside significantly reduced α–β coupling (localized to frontal and central regions). This reflects both an abnormal locking of slow-wave activity to the β band and a diminished regulatory role of α oscillations. (3) Clinical correlation: Notably, abnormally elevated PAC strength (particularly in the δ/θ/α–γ bands) showed a negative correlation with clinical symptom severity—that is, stronger coupling was associated with lower scores on the ABC. Conclusions: Leveraging a large-sample dataset, this study characterizes the landscape of aberrant cross-frequency interactions in young children with ASD. Our findings indicate that the neuroelectrical activity in ASD goes beyond mere connectivity anomalies by demonstrating altered PAC strength at both the intra-region and inter-region levels. Notably, the strength of this aberrant intra-region PAC is correlated with clinical symptoms. 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

Background/Objectives: Assessing inhibitory function and error detection is crucial for the early detection of age-related cognitive decline. This study aimed to investigate the neural network dynamics underlying these functions in younger and older adults to better understand age-related changes in cognitive control. Methods: We recorded electroencephalograms (EEGs) during an inhibitory control task in 17 older and 15 younger healthy adults. Behavioral performance was assessed, and directional functional connectivity was analyzed using Low-Resolution Electromagnetic Tomography (LORETA), isolated effective coherence (iCoh), and Full Vector Field analysis across the theta, alpha, and beta frequency bands. Results: Older adults showed significantly fewer correct responses than younger adults. During incorrect responses, older adults exhibited strong beta-band directionality from the ventral anterior cingulate cortex (ACC) to the left frontal polar cortex (FPC), alongside strong intra-ACC connectivity. During correct responses, they demonstrated alpha- and beta-band directionality from the left dorsolateral prefrontal cortex (DLPFC) to the right FPC. Conversely, compared with older adults, younger adults demonstrated significantly stronger mutual directionality within the ACC and widespread robust connectivity among the ACC, bilateral DLPFC, and FPC during correct responses. Conclusions: Efficient inhibitory control in older adults appears to rely on higher-order error-monitoring and error detection networks. The altered network dynamics in older adults suggest an age-related decline in immediate cognitive control. Evaluating these neural networks via EEGs provides a potential non-invasive biomarker for early cognitive decline and highlights higher-order executive control as a promising target for preventive interventions. Full article

One of the main technological challenges in plasma wakefield acceleration (PWFA) research and development is achieving stable and reproducible acceleration. In particular, for PWFA schemes based on particle-driven plasma wave excitation, beam stability and timing jitter are increasingly critical. In these configurations, magnetic or radio-frequency (RF) compression schemes are often used, and the beam time-of-arrival jitter at the end of the linear accelerator can be strongly correlated with the phase noise of RF accelerating structures operated off-crest. For this reason, since 2008, an RF phase fast-feedback system acting within each RF pulse has been successfully implemented at Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare (LNF-INFN) at the Sources for Plasma Accelerators and Radiation Compton with Laser And Beam (SPARC_LAB) facility, operating on both S-band ($2.856$ GHz) and C-band ($5.712$ GHz) klystrons. This paper presents the upgrade and optimization of the fast-feedback system for an S-band klystron powered by a pulse-forming network modulator. This technology introduces significantly higher intrinsic phase noise than, for instance, solid state-based modulators. It is therefore essential to minimize such phase fluctuations to keep the machine stability under control. Both the feedback hardware (electronic boards and RF circuitry) and the software (controller and user interface) have been upgraded. Tests performed at SPARC_LAB achieved a reduction in klystron-induced jitter of a factor of 30, reaching values below 15 fs rms on both power plants. Moreover, adding a remote control of the feedback loop enabled a straightforward optimization of the operating point, allowing the phase stability performance to be pushed close to its practical limits. A detailed analysis of RF phase noise measurements with the fast-feedback loop in operation is also presented. Full article

Cu–TiO₂ nanoparticles of a broad range of compositions with 0, 0.002, 0.005, 0.02, 0.05, 0.2, 0.5, 1.0, 2.0, 3.0, 5.0, 7.0 and 10.0 mol% Cu were synthesized via the sol–gel method using copper (II) acetate and titanium tetraisopropoxide (TTIP) precursors at a low hydrolysis ratio of H = 1.25, which favours homogeneous TiO₂ nucleation and Cu dispersion in the host matrix at nanoscale. The precipitated materials were dried at 80 °C and calcined at 450, 500, and 550 °C to form crystalline nanopowders, whose photocatalytic activity was evaluated on the decomposition of a representative pollutant, methylene blue (MB), in aqueous solutions under UVA and sunlight illuminations. The compositions with small Cu content of ~0.05 mol% showed the highest activity. A gain of activity over pure titania of 4 times after calcination at 450 °C, 2.5 times at 500 °C and 20% at 550 °C was measured under UVA illumination. Even higher gain of activity observed under sunlight illumination might be due to an extension of action spectrum to the visible range due to intra-gap defect states produced by Cu²⁺ insertion. The time-resolved microwave conductivity (TRMC) measurements of the photoinduced charges relaxation suggest that both excessive calcination temperature and Cu content decrease the activity due to Cu-defects clustering. Modelling relates the activity to the photoinduced electron-hole pair separation; the optimal Cu content is explained by accessibility of the recombination centre by a conduction band (CB) electron. Accordingly, an increase in calcination temperature resulted in a longer pathlength of CB electron. Full article