Search Results (27,751)

With the rapid growth of digital image transmission, ensuring data security has become increasingly important. However, existing chaos-based image encryption algorithms often suffer from insufficient chaotic randomness and weak integration between chaotic dynamics and encryption mechanisms. To address these issues, a novel image encryption scheme based on a two-dimensional hyperbolic–exponential Sine–Logistic map (2D-HESLM) is proposed. A Sierpiński carpet-inspired scrambling strategy and a cascaded diffusion mechanism are designed to enhance permutation and diffusion performance based on the 2D-HESLM. The experimental results show that the information entropy value is 7.9980, while NPCR and UACI are approximately averaged 99.6147% and 33.4672%, respectively, with correlation coefficients close to zero. These results demonstrate the effectiveness and security of the proposed scheme. Full article

Depletion of reserves of rich copper–porphyry ore deposits necessitates the development of highly efficient methods for Mo (VI) extraction from complex, corrosive hydro-metallurgical media. The present study undertakes a comprehensive assessment of sorptive concentration of Mo (VI) from strongly acidic sulfate solutions (120 g/L H₂SO₄) by employing a spectrum of commercially available strong- and weak-base anion-exchange resins. It has been established that the macroporous weak-base anion exchanger Purolite A-100 demonstrates decisive superiority over gel-type analogs (Lewatit M-800, AB-17), facilitating unimpeded intra-gel diffusion of bulky molybdenyl sulfato-complexes anions, thereby circumventing the obstructive “sieve effect.” Thermodynamic and kinetic investigations revealed that the sorption process exhibits pronounced concentration- and pH-dependent characteristics. Peak extraction efficiency (up to 95.91%) is achieved at pH ≈ 1, a finding that correlates with the region of maximal protonation of tertiary amino groups within the resin matrix. Kinetic acceleration of mass transfer upon heating to 80 °C has been experimentally confirmed, yielding 94.6% extraction within 60 min. The obtained results corroborate the prospective integration of macroporous weak-base anion exchangers into operational hydro-metallurgical schemes as an environmentally benign and efficacious alternative to conventional solvent extraction of molybdenum. Full article

The Mpemba effect refers to the counterintuitive situation in which a system initially farther from equilibrium can relax faster than one that starts closer to it. In quantum systems, the effect is enriched by the presence of coherent dynamics, dissipation, and metastable manifolds associated with long-lived Liouvillian modes. Here we demonstrate a giant Mpemba effect in open quantum systems, where relaxation can be either hyper-accelerated or dramatically slowed depending on the initial state. We focus on weakly-coupled particle-conserving bosonic networks, each of which independently relaxes rapidly to a unique stationary state. When a weak coherent interaction is introduced, the composite system typically develops slow metastable modes and a hierarchy of relaxation timescales. We show that by tailoring the interaction Hamiltonian, these slow modes can be effectively suppressed for a broad class of initial states satisfying a minimal global requirement, enabling ultrafast relaxation even when the system starts far from equilibrium. Conversely, other initial states—sometimes arbitrarily close to the stationary state—may remain trapped in the metastable manifold and decay anomalously slowly. This mechanism provides a general route to engineer giant Mpemba effects, offering new possibilities for controlling dissipative dynamics, accelerating state preparation, and manipulating relaxation processes in complex quantum devices. Full article

The Basel Accords refer to a series of international banking regulatory frameworks developed by the Basel Committee on Banking Supervision to strengthen the stability and resilience of the global banking system. Introduced as Basel I, Basel II, and Basel III, these accords establish minimum capital requirements, risk management standards, and supervisory principles for internationally active banks. Their primary purpose is to reduce the risk of bank failure, promote financial stability, and enhance consistency in banking regulation across jurisdictions. The Basel III framework and its 2017 Final Reforms represent the most advanced stage of this regulatory evolution, addressing weaknesses revealed by the global financial crisis and subsequent regulatory experience. Banking institutions play a central role in economic development, making their stability essential. The global financial crisis that began in 2007 exposed significant weaknesses in existing regulatory frameworks and led to the failure of several major banks, despite the earlier establishment of Basel I and Basel II by the Basel Committee on Banking Supervision. These shortcomings prompted the development of the Basel III framework as a direct response to the crisis. However, early criticisms of the initial Basel III Accord, particularly regarding variability in risk-weighted assets, reliance on internal models, and opportunities for regulatory arbitrage, led the Basel Committee to issue the Basel III Final Reforms in 2017, which represented a substantial upgrade to the post-crisis regulatory architecture. This study reviews the evolution of the Basel Accords; examines the key components of Basel I, Basel II, and Basel III; and analyses the enhancements introduced through the Basel III Final Reforms. It also considers the major arguments and criticisms surrounding these accords, highlighting the persistent challenges of achieving global regulatory consistency. Given the inability of earlier Basel frameworks to prevent bank failures and the fact that many jurisdictions have yet to fully implement the 2017 reforms, the paper underscores the need for ongoing evaluation of international banking regulation as national authorities adapt and refine their supervisory approaches to strengthen financial stability. Full article

Background: Untargeted metabolomics enables comprehensive profiling of biological systems, but accurate metabolite annotation remains a critical bottleneck due to incomplete spectral libraries and structural isomerism. The use of in silico annotation tools can increase the coverage of annotated compounds, but it remains unclear whether these tools, in the absence of reference standards, can reliably annotate real-world experimental LC-HRMS data and whether they are sufficient for this task. Methods: This study assesses the performance and limitations of four widely used in silico structure prediction tools (MassFrontier, MetFrag, MS-FINDER, and SIRIUS/CSI:FingerID) when applied to an experimentally acquired feature set previously used to differentiate patients with depressive disorders from healthy controls. To ensure uniform evaluation across tools under realistic but optimized conditions, the quality of MS/MS data was improved using a parallel reaction monitoring method, allowing acquisition of interpretable fragmentation spectra for 26 of the 28 detected features. Results: For most features, all tools were able to suggest structure candidates. However, none of the tools proved sufficient as a standalone solution for reliable metabolite annotation. Due to their different algorithms, each tool had strengths and weaknesses in fragmentation interpretation, candidate generation, and ranking, resulting in incomplete or inconsistent annotations. While the combined application of all four tools provided a substantial improvement in putative annotation over conventional spectral library matching, the in silico structure prediction tools often prioritized chemically implausible, biologically irrelevant, or artifactual candidates. Consequently, manual expert evaluation was required to assess the chemical plausibility and biological relevance of the proposed structures. This ultimately reduced the number of biologically plausible metabolites putatively associated with disease to ten. Conclusions: Overall, these results demonstrate that existing in silico annotation tools can substantially support the annotation of experimental metabolomics data, but are insufficient on their own. Reliable identification of metabolites in complex biological matrices still depends on high-quality MS/MS data acquisition, the combined use of complementary tools, and mandatory post-annotation expert curation. Full article

Vitamin D plays an important role in bone metabolism and may influence postoperative healing processes. This study evaluated the association between preoperative serum vitamin D levels and recovery after mandibular third molar extraction. This secondary exploratory analysis included 122 healthy patients undergoing surgical extraction of an impacted mandibular third molar, of whom 98 had complete datasets for clinical and radiographic evaluation. Postoperative outcomes included pain intensity, facial swelling, trismus, early soft tissue healing assessed with the Wachtel Early Healing Index, and bone regeneration evaluated four months after surgery using CBCT-based fractal dimension analysis. Serum vitamin D levels were not significantly associated with postoperative pain, trismus, or early soft tissue healing. A weak correlation was observed between lower vitamin D levels and greater swelling along the tragus–pogonion line on postoperative day 1 (ρ = −0.21, p = 0.035), with no significant associations at later time points. Fractal dimension analysis did not demonstrate significant differences between groups. Within the limitations of this secondary exploratory analysis, vitamin D levels showed limited and inconsistent associations with postoperative outcomes, and their clinical relevance remains uncertain. Full article

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease marked by progressive degeneration of motor neurons and skeletal muscle. Gene expression analysis of the spinal cord and gastrocnemius of the SOD1-G93A ALS mouse model revealed a strong increase in inflammatory pathways and, specifically in the ALS gastrocnemius, a decrease in mitochondrial transcription and an increase in ribosomal protein expression. Treatment of ALS mice with the polyamine spermidine (SPD), a promising molecule in combating neurodegeneration and muscle atrophy, is able to partially restore the expression of more than four thousand genes in gastrocnemius tissue, including the mitochondrial regulator Pgc1α, as well as all the mitochondrial encoded genes and a large class of ribosomal proteins. SPD enhanced mitochondrial bioenergetics, as evidenced by Seahorse experiments, and delayed muscle weakness in vivo, as shown by grip strength records. These findings suggest that SPD can act as a potential supplement in the therapeutic strategy for ALS, offering a foundation for further research to improve patient outcomes. Full article

One promising innovative joining process for non-oriented electrical sheets is based on an electro-insulating layer combined with a self-bonding varnish. The aim of this study was to investigate the adhesion of the self-bonding varnish as evaluated by a lap-shear test. During the experiments, non-oriented electrical steels with low to high silicon content were analyzed and tested. The Si content, the bond thickness, and the surface roughness Ra, as well as the selected steel production parameters—such as the radiation tube furnace temperature (RTF), the grain growth temperature (i.e., heating temperature (HF)), the peak metal temperature (PMT), and the annealing atmosphere (dry or humid, controlled by dew point)—were considered as the variables. The results showed that the lap-shear strength was independent of the surface roughness within the investigated range. In contrast, the bond thickness exhibited a weak positive effect on the lap-shear strength, while the Si content showed condition-dependent behavior. The RTF and the HF resulted in a relatively stable mechanical performance, whereas the PMT and the humid annealing atmosphere were identified as critical factors influencing adhesion. Full article

Madagascar’s expanding blue economy is largely underpinned by seaweed aquaculture, particularly Kappaphycus alvarezii (Cottonii), which offers an alternative to declining small-scale fisheries and strengthens the resilience of coastal socio-ecosystems. Ensuring the sustainability of this economic activity requires effective ecological monitoring of aquaculture sites and surrounding habitats. This study examines and compares the performance of two imaging configurations—an RGB composite derived from a subset of multispectral images capturing red (650 nm), green (560 nm), and blue (450 nm) bands; and a five-band multispectral (MS) image encompassing blue, green, red, red-edge (730 nm), and near-infrared (840 nm) bands—combined with a Random Forest (RF) classification model, for benthic habitat mapping in a seaweed cultivation context. High-resolution orthomosaics (2 cm/pixel) enabled the discrimination of Kappaphycus cultivation plots from three shallow-water habitats: (i) ‘benthic macrophytes’, which comprise: seagrass meadows and benthic macroalgal; (ii) ‘sandy bottom’ and (iii) ‘green algae’. The RF classification achieved an overall accuracy of 87% (Kappa = 0.82) across ~10 hectares. Producer’s accuracy exceeded 80% for Kappaphycus cultivation, green algae, and sandy bottom for both the RGB and MS datasets, indicating strong classification performance. However, early-stage seaweed was occasionally misclassified as benthic macrophytes, likely due to its low biomass and weak spectral signature. This UAS-based approach provided a robust and cost-effective framework for monitoring off-bottom seaweed farms and associated natural habitats. This approach supports sustainable aquaculture development and integrated coastal management in Madagascar and comparable tropical reef socio-ecosystems. Full article

Weak-echo ship target detection in GNSS-based bistatic synthetic aperture radar is severely limited by the coupled effects of burst-type strong windows and polarization mismatch, cross-frequency mis-registration, and long-sequence chain drift in dual-frequency dual-polarization observations. To address these issues, this paper proposes DFDP-QuadDiff, a dual-frequency dual-polarization quad-differential framework for weak-echo ship target detection using B1/B3 × horizontal–horizontal (HH)/vertical–vertical (VV) four-channel complex range-time data. The proposed framework integrates polarization-consistency-driven strong-window suppression, intra-band adaptive polarimetric synthesis, joint delay–Doppler–phase cross-frequency registration, segment-wise Jones drift calibration, and quality-aware final fusion in a unified hierarchical processing chain. In this way, multi-source inconsistencies are progressively constrained and suppressed from the polarization level to the segment level before final accumulation and detection are performed. Experimental results on self-developed four-channel GNSS-S demonstrate that, relative to the best raw single-channel result, the proposed framework increases the median SCR from 6.51 dB to 9.04 dB (+2.53 dB), improves the P10 SCR from −1.76 dB to 3.05 dB (+4.81 dB), and raises the track continuity from 0.85 to 0.97. In addition, the standard deviation of segment-wise delay drift is reduced from 0.97 bin to 0.29 bin, and positive multi-scale accumulation gains are maintained up to the second-long integration range. These results indicate that the proposed framework not only substantially enhances the stability, continuity, and long-time integrability of weak-target responses under low-SNR maritime conditions, but also maintains robust gains under weak-visibility, interference-dominant, and mismatch-sensitive local conditions in the stratified evaluation, thereby establishing a physically interpretable and implementation-ready solution for collaborative weak-target detection in dual-band dual-polarization GNSS-S. Full article

Weak alternating electric fields are widely used in neuromodulation techniques such as transcranial alternating current stimulation (tACS), yet the precise biophysical mechanisms underlying neuronal responses remain incompletely understood. Current computational models often neglect the electrical properties of the extracellular microenvironment, limiting their predictive accuracy. Motivated by experimentally observed frequency-dependent modulation of neuronal activity, we developed a two-compartment model of hippocampal CA3 pyramidal neurons in which extracellular resistance is explicitly parameterized and systematically examined as a key factor influencing neuronal response properties under external electric fields. Within a dual-compartment Hodgkin–Huxley framework, the neuron is divided into a “soma–basal dendrite unit” and an “apical dendrite unit,” accounting for voltage polarization induced by external fields. Using phase-locking ratio curves and three-dimensional parameter response surface, we systematically characterized neuronal sensitivity to field parameters and examined how potassium equilibrium potential ($V_K$) and extracellular resistance ($R_{\mathrm{out}}$) modulate these responses. Our results demonstrate that increasing $R_{\mathrm{out}}$ enhances neuronal responsiveness to external fields, while $V_K$ variations primarily regulate intrinsic excitability. These findings provide mechanistic insights into the frequency-dependent modulation of neuronal responses under weak electric fields, consistent with phenomena observed in biological neural systems, and provide a mechanistic and theoretical framework for understanding the joint effects of electric field amplitude and frequency on neuronal sensitivity to weak electric fields, which may help inform future neuromodulation strategies. Full article

As a part of our research on the presence of conglomerates among the aryl benzyl sulfoxides, racemic-benzimidazolyl pentafluorobenzyl sulfoxide was synthesised, and its crystal structure was determined by a single crystal X-ray diffraction experiment. The main interactions building up the crystal structure were recognised and compared with those of similar compounds. Since the crystal structures of racemic and enantiopure benzimidazolyl pentafluorobenzyl sulfoxides are different, the presence of a conglomerate is excluded in the present case. Full article

Objective: The purpose of this study was to determine the biological association between host-derived HSP47 and fungal-derived HSP90 in the context of vulvovaginal candidiasis (VVC) and to examine their relationships with clinical, inflammatory, and metabolic phenotypes in infected and healthy women. Methods: This study followed a six-month case–control design (February–July 2025) and was conducted at the University of Tabuk Hospital in Tabuk, Saudi Arabia. A total of 84 women aged 18–45 years were recruited, of which 42 were VVC-infected, and 42 were healthy controls. ELISA kits were used to test vaginal swabs for HSP47 and HSP90. Clinical, hematological, cytokine, and metabolic markers were also evaluated. Mann–Whitney U, Spearman correlation, and multiple linear regression tests were performed to analyze the data. Results: The levels of HSP47 and HSP90 were significantly higher among infected patients (2.29 ng/mL and 3341 ng/mL, respectively) when compared with controls (0.58 ng/mL and 1025.7 ng/mL; p < 0.001). Women who were infected were older (p = 0.02), but there were no significant differences in terms of BMI (p = 0.29). The levels of vitamin D and adiponectin were significantly decreased (p < 0.001), while pro-inflammatory cytokines (IL-6, TNF-α, IFN-γ, TGF-β, and IL-8) and WBC counts were higher compared to the control group. The hematology results were characterized by inflammation-related anemia and disturbed protein metabolism. The ROC analysis demonstrated good diagnostic performance, with an AUC of 1.0 in the case of HSP47 and 0.905 in the case of HSP90. In the case of the infected patients, the regression models were found to be weak (HSP90 R² = 0.154; HSP47 R² = 0.273), although HSP47 retained significant connections with IL-8 (p = 0.005) and IFN-γ (p = 0.028). Conclusions: High levels of HSP47 and HSP90 are observed in VVC, reflecting an epithelial stress response and fungal persistence. These HSPs have high diagnostic accuracy, which justifies their potential as biomarkers for the timely detection of VVC; they also have further implications as early biomarkers for prognostic and treatment monitoring support, despite the poor predictive models. This study has some limitations that must be addressed; in particular, the regression analyses failed to provide statistically significant predictive models, likely due to the limited sample size. In addition, the specificity of HSP90 and HSP47 for VVC in comparison with other vaginal infections was not evaluated. Full article

High-alkali coal can cause slagging and fouling and impact the operational lifespan of the boilers. Traditional single-indicator methods often yield inconsistent results when evaluating the slagging risk of high-alkali coal. In this study, six coal samples were selected and systematically analyzed for their slagging characteristics using scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), and ash morphology analysis. Furthermore, a comprehensive evaluation model was constructed by integrating the technique for order preference by similarity to ideal solution (TOPSIS) with the entropy weight method. Additionally, based on images of ash morphology, the fractal dimension (D) was introduced as a quantitative indicator to predict slagging tendency through crack characteristics. The results show that TF, ZD, and KB samples, which are rich in alkaline oxides (CaO, Fe₂O₃, Na₂O, K₂O), form low-melting-point eutectic silicates during combustion, resulting in significant melting and agglomeration with wide cracks between aggregates, indicating a strong slagging tendency. Their fractal dimensions (D) range from 1.81 to 1.92. In contrast, HM and WQ samples, dominated by SiO₂ and Al₂O₃, form high-melting-point mullite and quartz, showing loose ash morphology with uniformly distributed cracks and a weak slagging tendency, with D values of 1.68 and 1.75, respectively. A significant negative correlation was observed between D and the E-TOPSIS model (y = 3.54 − 1.72x). Therefore, fractal analysis allows for rapid assessment of slagging risk without the need for complex chemical testing. This study provides valuable insights for predicting the slagging tendency of high-alkali coal during combustion. Full article

New quality productive forces are increasingly recognized as important drivers of coordinated regional development, with urban agglomerations acting as key vehicles for their spatial implementation. Based on the theory of new quality productive forces, this study takes the 13 cities in the Beijing–Tianjin–Hebei (BTH) urban agglomeration as its research subjects, spanning the period from 2005 to 2023, and constructs a four-dimensional evaluation index system for new quality productive forces covering economic, social, ecological, and technological dimensions. It employs the entropy method to determine indicator weights and calculate development indices for each dimension and utilizes a coupling coordination model to measure the overall and subsystem-level coordination by analyzing their spatiotemporal evolution characteristics. The results indicate a steady upward trend in the overall coordination level, progressing from a low level to an intermediate level, with the state of coordination continuously improving; spatial differentiation is significant, forming a gradient development pattern centered on Beijing, with marked disparities in coordination levels among cities. Subsystem analysis reveals an imbalanced synergy structure: while economic and ecological synergy levels are relatively high, the coupling and synergy between science and technology and the economy and society remain prominent weaknesses. Most cities in Hebei Province lack sufficient scientific and technological innovation capabilities, resulting in a weak supportive role for economic and social development. Based on these findings, this study proposes policy recommendations such as establishing a regional innovation community, promoting the integration of factor markets, and strengthening collaborative governance of the ecological environment, with the aim of leveraging new quality productive forces to drive a qualitative leap in the coordinated development of the BTH urban agglomeration. Full article