Search Results (313)

Low-visibility weather poses a significant threat to aviation safety and operational efficiency. Lhasa Airport is situated in a high-altitude river valley region prone to dust events. Clarifying the characteristics and dominant factors of low-visibility weather is crucial for enhancing aviation meteorological support capabilities. This study systematically analyzed the weather types, spatiotemporal distribution characteristics, and key meteorological influencing factors of low-visibility events using ground-based automated meteorological observation data, monthly summary records, and wind lidar data from Lhasa Airport from January 2020 to July 2024. The results indicate that dust weather (blowing sand and floating dust) is the primary cause of low visibility, accounting for over 90% of low-visibility days. Low-visibility events exhibit significant monthly variations, with the longest cumulative duration occurring in January and February, while being extremely rare from July to November. Under low-visibility conditions, visibility levels are predominantly concentrated in the 3–4 km range (72.5%), and most events last less than one hour. Factor analysis reveals that north, easterly, and west winds are commonly associated with dust-induced low visibility. Wind speed demonstrates a significant negative correlation with visibility and serves as the primary driving factor. Moderate relative humidity is most conducive to maintaining visibility between 3 and 5 km. Case studies further confirm that sustained strong low-level winds (≥10 m/s), high surface wind speeds (≥7.5 m/s), and intense upward motion are the key dynamic conditions for triggering and maintaining dust-related low-visibility processes. This study presents, for the first time, quantitative thresholds for key meteorological parameters and their season-dependent characteristics for dust-induced low-visibility events at Lhasa Airport, and proposes actionable forecasting indicators. These findings offer clear practical implications for aviation meteorological services at high-altitude valley airports. Full article

Gadolinium [Gd (III)] released from gadolinium-based contrast agents, commonly used in magnetic resonance imaging, may accumulate in organs, altering metal homeostasis. We aimed to clarify Gd (III), iron and other metal accumulation in the kidney and brain, in the short (2 days) and long term (20 weeks), following exposure to gadoteric acid (Gd-DOTA) or free Gd (III). Wistar rats received one dose of Gd (III), Gd-DOTA, or saline. Gd (III) and metal levels in the blood (whole blood, and serum in the case of iron), kidney, and brain, and iron metabolism biomarkers, were assessed. Gd (III) was detectable in the blood, kidney, and brain, at both time points, for both Gd (III) and Gd-DOTA-treated groups. Exposure to free Gd (III) showed a significant Gd (III) accumulation in the kidney, brain and blood in the short term and long term; Gd-DOTA presented significant accumulation only in the short term. Gd-DOTA appears to have faster elimination and minimal brain deposition. Exposure to free Gd (III), but not to Gd-DOTA, led to disturbances in metal homeostasis and in iron metabolism markers (serum ferritin and transferrin saturation), but did not alter tissue iron levels. In summary, the kidney appears as the primary site of accumulation and retention. Despite the safer profile shown by Gd-DOTA in the long term, our data highlight the importance of clarifying the pathophysiological implications of Gd (III) retention and/or accumulation, particularly in vulnerable conditions and repeated exposures. Full article

Cooperative adaptive cruise control (CACC), as an extension of adaptive cruise control (ACC), is an intelligent transportation approach for connected and automated vehicles. By using vehicle-to-vehicle information, CACC improves longitudinal tracking performance, traffic throughput, and string-stable platoon behavior. However, controller tuning remains sensitive to vehicle-dynamics parameters, spacing-policy selection, fractional-order dynamics, and communication delay. This paper presents an analytical parameter-space-based fractional-order PD (FOPD) controller synthesis framework for string-stable CACC systems. For the constant-time headway spacing policy, the controller parameters are investigated in the $(k_p,k_d,\mu )$ parameter space, where the fractional differentiation order $\mu$ is considered as an additional design variable. To obtain the feasible stabilizing regions, the fractional-order characteristic equation is evaluated on the imaginary axis, and the delay-dependent stability boundaries are derived through a frequency-domain boundary-locus formulation. The stabilizing gain regions are constructed through the complex-root boundary (CRB), real-root boundary (RRB), and infinite-root boundary (IRB), which provide an interpretable graphical basis for controller-gain and fractional-order selection. In addition, the effect of the headway time on the admissible stability region is examined jointly with the fractional order. The proposed structure is implemented with a feedforward controller that uses the acceleration information of the preceding vehicle under a predecessor-vehicle-following communication topology. The selected fractional-order CACC (FO-CACC) controller is validated in an eight-vehicle platoon simulation environment and compared with integer-order ACC (IO-ACC), fractional-order ACC (FO-ACC), and integer-order CACC (IO-CACC) configurations. The results show that the proposed parameter-space approach enables systematic FOPD tuning and that the selected FO-CACC controller satisfies the frequency-domain string-stability requirement while maintaining smooth time-domain responses in position, velocity, acceleration, headway time, spacing error, and control input. Additional simulations under the New European Driving Cycle (NEDC) and the FTP-75 (Federal Test Procedure 1975) driving cycles further indicate that the proposed FO-CACC structure maintains accurate spacing regulation and bounded acceleration behavior under standard drive-cycle conditions. Overall, the results indicate that the fractional-order parameter provides an effective design freedom for improving string-stable cooperative platoon performance. Full article

Obesity and dental caries are highly prevalent chronic conditions with significant global health impact. Although an association between these diseases has been suggested, the nature of this relationship remains unclear. This state-of-the-art review aims to synthesize current evidence on the interplay between obesity and dental caries, focusing on shared risk factors, salivary alterations and underlying biological mechanisms. Evidence indicates that obesity and dental caries share common behavioral and socioeconomic determinants, namely unhealthy dietary patterns with high intake of free sugars, poor oral hygiene habits and social disadvantage. Salivary alterations observed in obesity may also create a more cariogenic oral environment. Additionally, inflammatory mediators, oxidative stress markers and changes in the oral microbiome suggest biologically plausible links between both conditions. However, current data does not support a direct causal relationship, but rather a complex multifactorial interaction between obesity and dental caries driven by shared risk factors and modifiable behaviors. Preventive strategies should adopt an integrated approach targeting shared determinants, particularly diet, oral hygiene habits and socioeconomic status. Nevertheless, the predominance of cross-sectional evidence limits causal inference, highlighting the need for longitudinal studies that simultaneously assess obesity and dental caries, and that address salivary biomarkers using standardized methodologies across different age groups to clarify underlying mechanisms and assess their clinical relevance. Full article

Secure vehicle-to-vehicle communication is essential for electric-vehicle platoons because broadcast wireless links may expose safety and control messages to passive eavesdropping. This paper investigates a physical-layer security (PLS) framework for electric-vehicle (EV) platoons under Rician fading, representing the line-of-sight conditions common in highway platooning. The proposed Jamming-Aided Cooperative Relay Selection (JACRS) framework uses an amplify-and-forward relay, destination-assisted full-duplex friendly jamming, residual self-interference modelling, and a strict total transmit power budget. Relay selection is evaluated using a full-channel state information (CSI) secrecy-selection benchmark, a practical legitimate-link CSI rule, and a deterministic platoon-geometry-aware rule based on Cooperative Adaptive Cruise Control (CACC) position information without instantaneous eavesdropper CSI. Monte Carlo simulations, supported by semi-analytical secrecy-outage and deterministic-slot benchmarks, compare the proposed scheme with Rayleigh and no-jamming amplify-and-forward (AF) baselines. Under the simulated geometry, the scheme achieves a peak ergodic secrecy rate close to 5.0 bps/Hz at 40 dBm and reduces interception risk by 78.07% relative to the Rayleigh baseline. Relay diversity reduces secrecy outage from 14.14% to 0.04% under full CSI and to 0.22% using legitimate-link CSI. The geometry-aware rule reduces the gap between practical legitimate-link selection and the full-CSI benchmark, indicating that platoon position information can improve relay selection under the tested conditions. Full article

Chronic inflammation mediated by cytokines is central to the pathogenesis of coronary artery disease (CAD). This exploratory study aimed to investigate potential associations between functional gene variations of the cytokines interleukin 18 (IL-18) and interleukin 8 (IL-8) and the CAD susceptibility within a specific regional cohort, while accounting for common clinical comorbidities. Genotype distributions of IL-18 (−607 C/A, −137 G/C) and IL-8 (+781 C/T) were analyzed in a cohort of 102 patients with angiographically confirmed CAD and 102 healthy controls. Genotyping was performed using PCR, allele-specific PCR, and RFLP techniques. Multivariate logistic regression was utilized to assess potential independent associations, adjusting for age and traditional clinical risk factors. In this specific cohort, after adjusting for age, hypertension, diabetes, cholesterol, family history, and smoking, the IL-18 (−137 G/C) CC genotype was observed more frequently in CAD patients (adjusted odds ratio [AOR] = 6.15, 95% CI = 2.10–18.05, p = 0.001). An exploratory analysis of genotype combinations suggested that the IL-18 (−607/−137) CA-CC profile may be linked to an increased risk (AOR = 3.65, p = 0.028), while tentative protective trends were noted for certain IL-18/IL-8 combinations. Notably, a significant deviation from a Hardy–Weinberg equilibrium (HWE) was observed in the control group for the IL-18 loci, which represents a substantial methodological limitation that may influence these risk estimates. Our preliminary findings suggest that specific IL-18 and IL-8 variations may contribute to CAD susceptibility independently of traditional risk factors in the studied population. However, given the modest sample size and the observed HWE deviation, these associations should be regarded as suggestive rather than definitive. While these genetic variations underscore the importance of cytokine pathways in cardiovascular research, they do not currently support clinical implementation for risk stratification. Large-scale, multi-center prospective studies are necessary to validate these preliminary signals and evaluate their long-term scientific utility. Full article

This paper proposes a calibration-oriented framework for cooperative adaptive cruise control based on a linear quadratic regulator formulation. A simulation-based architecture is developed by integrating the controller with a nonlinear longitudinal platoon model that explicitly accounts for actuator saturation and tyre–road friction limits, enabling the analysis of platoon behaviour under realistic operating conditions. A systematic offline calibration methodology is introduced based on multidimensional performance maps, relating key performance indicators associated with collision avoidance, comfort, and energy efficiency to controller and spacing-policy tuning parameters. The map-based approach enables a structured exploration of competing objectives and provides a quantitative assessment of controller sensitivity. The results show that the proposed framework can identify calibration regions that preserve collision-free operation in safety-critical manoeuvres while maintaining satisfactory tracking and comfort-related performance. In addition, the off-nominal model parameters analysis confirms that the proposed calibration approach remains effective under heterogeneous operating conditions, including vehicle parametric variation of mass, rolling resistance coefficient and drag. Overall, the results support the use of the proposed methodology as a practical tool for robust and performance-oriented controller calibration. Full article

Essential oils have attracted increasing attention due to their bioactive properties. This review focuses on their anticonvulsant potential by exploring the relation between the chemical composition of essential oils and the mechanism of action underlying this effect. Evidence from in vivo and ex vivo studies is presented to identify structure–activity relations and to distinguish well-supported effects from preliminary findings. Moreover, essential oil’s quality is vital to ensure safety and efficacy in pharmacotherapeutic approaches. For this reason, factors including extraction and analytical methods as well as authenticity assessment are discussed due to their impact on pharmacological consistency and reproducibility. Overall, this review highlights key compounds and mechanisms contributing to anticonvulsant activity, identifies current limitations in the literature, and outlines priorities for future research aimed at validating essential oils as potential complementary therapeutic agents in seizure management. Full article

Objectives: Real-world information on relapsed and/or refractory multiple myeloma (rrMM) clinical management in Portugal is scarce. The CharisMMa Portugal study aimed to characterize rrMM patients through socio-demographic and clinical parameters and describe treatment patterns. Methods: This was an observational, cross-sectional, multicenter study with 62 rrMM patients routinely treated at seven hospitals in Portugal. Data were collected from medical records during clinical appointments (2020–2022) after written informed consent was obtained (ClincialTrials.gov ID-NCT04135963). Patients who were diagnosed with a symptomatic MM episode in the 6 months prior to study initiation and who received treatment before their last relapse episode were enrolled. Results: Most patients were male (54.8%) and living with relatives (90.3%), and almost 50% were independent. Roughly 70% of patients were classified as Revised MM International Staging System (R-ISS) Stage II at diagnosis, with a mean age of 65.76 (±9.24) years old. Most common SliM-CRAB (SLIM: sixty percent or more clonal plasma cells in the bone marrow (S), light chain ratio ≥100 (Li), and MRI-detected focal lesions (M); CRAB: hypercalcemia (C), renal insufficiency (R), anemia (A), and bone lesions (B)) signs were bone lesions (59%), and 62.9% of the patients had at least one comorbidity. At study initiation, 70.5% of patients were on second-line treatment, with monoclonal antibodies and proteasome inhibitors (PIs) + immunomodulators (IMiDs) as leading agents. Triplet regimens were the most common across all lines, while oral and oral + subcutaneous were the most prevalent routes of administration. Conclusions: Triple treatment combinations are common in rrMM management, with PIs and IMiDs frequently used, especially in first-line settings. The use of oral formulation is substantial, suggesting a step toward more patient-centric options. This characterization underscores the complexity of rrMM management and should inform stakeholders of strategies to standardize patient care across reference centers in Portugal. Full article

This paper presents a deployment-oriented longitudinal platoon-control architecture for connected and autonomous vehicles operating under repeated leader hard-braking, cut-ins, and spatially varying road friction. The proposed stack combines four elements: (i) a lightweight scalar Kalman filter (KF) that smooths a friction-related signal and feeds friction-dependent constraint tightening; (ii) a model predictive control (MPC) backbone whose weights and horizon are selected offline using multi-objective GA/NSGA-II tuning; (iii) a bounded proximal policy optimization (PPO) residual policy, trained with the aid of a learned surrogate model, that refines the MPC command during transient events; and (iv) a command-level safety projection that enforces instantaneous actuation and clearance constraints at the fast control tick. The contribution is therefore not a new MPC formulation or a new reinforcement-learning algorithm in isolation, but an integrated and experimentally characterized control stack that keeps the safety-critical structure explicit while using learning to improve transient behavior. The method is evaluated in a CARLA digital twin of a six-vehicle platoon over a 5 km mixed urban–highway route and is further assessed in hardware-in-the-loop (HIL) on an automotive ECU using a multi-rate ROS 2/AUTOSAR implementation (50 Hz estimation/safety loop, 10 Hz MPC/RL refresh). Across 10 held-out disturbance seeds, the full stack improves spacing regulation, maintains non-amplifying disturbance propagation according to the reported string-stability indices, and reduces a route-normalized positive tractive-energy-at-the-wheels proxy by about 12% relative to Manual MPC and by up to 18% relative to a PID-CACC reference. Because the PID-CACC baseline does not enforce hard constraints and can collide under the tested disturbance suite, the main performance comparison is among collision-free controllers. The friction signal used in CARLA is derived from simulator road-surface annotations before filtering, so the present study should be interpreted as a friction-aware control and integration study rather than a validated onboard friction-estimation result. Likewise, the reported energy metric is an effort proxy and is not a calibrated fuel or battery consumption model. Full article

Background/Objectives: Skin candidiasis is a key contributor to chronic, non-healing wounds, largely due to persistent microbial infections. Candida species can colonize the skin, form protective biofilms, and interfere with enzyme activity, leading to extracellular matrix degradation, changes in pigmentation, and impaired wound healing. The rising prevalence of antifungal resistance challenges its management, underscoring the need for more effective antifungal therapies. Therefore, this study aimed to assess the antifungal effects and wound-healing potential of essential oils (EOs) from Ferulago spp. Methods: The antifungal activity of the EOs from five Ferulago species was evaluated against Candida spp. and Cryptococcus neoformans. The most active EOs were further investigated for their effects on C. albicans virulence factors, including germ tube formation, as well as biofilm formation and disruption. These effects were assessed using microscopic observation, XTT reduction assay, and crystal violet and safranin stainings. The wound-healing potential of the EOs was evaluated using the scratch-wound assay on fibroblasts and keratinocytes. Additionally, the effect on tyrosinase and elastase activity, was also investigated. Results:F. silaifolia and F. cassia essential oils showed fungicidal activity against Candida spp. and Cryptococcus neoformans. F. silaifolia displayed greater potency, with lower MIC and MLC values. Both oils inhibited key C. albicans virulence factors at sub-MIC concentrations. F. silaifolia EO was more effective in preventing biofilm formation whereas F. cassia EO showed notable tyrosinase inhibitory effect. Conclusions: These findings align with traditional uses and suggest that F. silaifolia and F. cassia EOs exhibit antifungal activity alongside properties associated with wound healing, supporting their potential as topical antifungal agents and thereby justifying further investigation. Full article

This in vitro study evaluated the effect of irrigation on different polishing protocols and their influence on the surface roughness, microhardness, and mass of resin composites. Three resin composites (Admira^® Fusion, Filtek Supreme™ XTE, and Ceram.X Spectra™ STHV) were polished using four systems (Sof-Lex™, DIATECH^® ShapeGuard, Astropol^®, and Enhance™/PoGo™) under wet and dry conditions. Eight test groups were established for each resin composite (n = 10 per group). Vickers microhardness, surface roughness (R_a), and specimen mass were measured before and after polishing with one of the four systems, applied either with or without irrigation. For Admira^® Fusion polished with Sof-Lex^™, R_a values were lower without irrigation (p = 0.048), whereas Filtek Supreme^™ XTE and Ceram.X Spectra^™ STHV polished with the Enhance^™/PoGo^™ system showed lower R_a values when irrigation was used (p = 0.010 and p = 0.004, respectively). Sof-Lex^™ and DIATECH^® ShapeGuard produced the highest microhardness values for both Admira^® Fusion and Filtek Supreme^™ XTE. Moreover, specimens of Admira^® Fusion and Ceram.X Spectra^™ STHV polished with DIATECH^® ShapeGuard exhibited higher microhardness under irrigation (p = 0.048 and p = 0.027, respectively). Overall, polishing resulted in measurable material removal, reflected by a reduction in specimen mass, and in an increase in microhardness. Wet polishing generally increased microhardness, although the effect varied depending on the polishing system and resin composite. Clinicians should therefore consider both the resin composite and the polishing system when deciding whether to use irrigation, as appropriate irrigation control may help optimize the surface smoothness and microhardness of resin composite restorations. Conference Presentation: Preliminary data from this study were previously presented as an oral communication at the 32nd Portuguese Dental Association Annual Meeting. This manuscript represents a substantially expanded and revised version, developed as a full research article. Full article

Butyrate, a short-chain fatty acid produced by the fermentation of soluble dietary fiber by gut bacteria, also functions as a histone deacetylase inhibitor known to induce apoptosis and promote differentiation in colon tumor cells. During tumorigenesis, cancer cells undergo metabolic reprogramming to meet energetic and biosynthetic demands, increasing glycolytic metabolism and reducing oxidative metabolism—a phenomenon known as the Warburg effect. This study aimed to evaluate the impact of butyrate on the aggressiveness-related metabolic phenotype of three colon cancer cell lines (LS1034, C2BBe1, and WiDr). Butyrate’s effects were assessed through fluorine-18 fluorodeoxyglucose ([¹⁸F]FDG) uptake, flow cytometry analysis of cytoplasmic and membrane expression of glucose transporters (GLUT1, GLUT3, GLUT5, and GLUT12), lactate production, and analysis of Krebs cycle turnover and glycolysis–Krebs cycle coupling using nuclear magnetic resonance isotopomer profiling. [¹⁸F]FDG uptake decreased in C2BBe1 and WiDr cells, whereas an opposite response was observed in LS1034 cells, which also exhibited reduced GLUT5 expression. These uptake patterns were consistent with lactate production measurements, and an enhancement of oxidative metabolism was detected in C2BBe1 and WiDr cells. Although butyrate was consumed by all three cell lines, its metabolic handling appeared to differ in LS1034 cells, possibly reflecting cytotoxic stress and/or distinct metabolic regulation mechanisms. Overall, these findings indicate that butyrate exerts cell-line-dependent metabolic effects in colorectal cancer cells. In C2BBe1 and WiDr cells, butyrate exposure was broadly consistent with the attenuation of glycolytic/Warburg-associated features, whereas LS1034 cells displayed a divergent response and were interpreted separately. These data support further investigation of butyrate as a modulator of colorectal cancer cell metabolism, while highlighting the heterogeneity of metabolic responses across tumor models. Full article

Background: Cleft lip and/or palate (CLP) is a common craniofacial malformation with aesthetic, functional, and psychosocial impacts. Although surgical repair is performed early in life, scar tissue formation may intensify maxillary deformities. Presurgical orthopedic interventions have therefore been introduced to optimize anatomical conditions prior to surgery. This scoping review aimed to systematically map presurgical orthopedic approaches described in the literature for patients with CLP. Methods: A Scoping Review was conducted in accordance with PRISMA-ScR guidelines. The protocol was registered in the Open Science Framework. Searches were performed in PubMed, Embase, Web of Science, and Cochrane databases without language or date restrictions. Two independent reviewers assessed the articles and extracted data. Results: A total of 207 studies were included, with a predominance of case series, case reports, and cohort studies, reflecting a generally low level of evidence. Nasoalveolar molding (NAM) was the most frequently reported intervention, while other appliances such as the Hotz plate and Latham device were considerably less represented. Across studies, reported outcomes included reduction of the alveolar cleft, improved nasal symmetry, and facilitation of feeding; however, variability in protocols and outcome measures limited comparability. Conclusions: The available evidence is heterogeneous and largely based on observational designs, which restricts definitive conclusions regarding the comparative effectiveness of presurgical orthopedic approaches. The predominance of NAM in the literature may reflect clinical preference rather than superior evidence, highlighting the need for standardized protocols and higher-quality studies. Full article

A major challenge in cancer treatment is the presence of cancer stem cells (CSC), which play a significant role in therapeutic resistance, metastatic progression, and tumor relapse, highlighting their importance as therapeutic targets. Photodynamic therapy (PDT) can be a valuable strategy for targeting CSC by increasing reactive oxygen species via light-activated photosensitizers, thereby counteracting CSC features of resistance. Therefore, this manuscript reviews the existing evidence on PDT-based approaches targeted at CSC. The literature search was conducted using the Medline (through PubMed), Web of Science, and Embase databases. The inclusion criteria were in vitro, in vivo, and clinical studies addressing PDT-based therapeutic strategies targeting CSC. A total of 37 publications were included in this review. From this analysis, we identified several studies with CSC-associated targets, delivery of PDT systems to CSC, novel nanoplatforms that disrupted the CSC microenvironment, and combined strategies to enhance PDT efficacy. The existing strategies have shown success in reducing CSC populations across different cancers by decreasing viability and tumor growth, as well as limiting stemness properties. However, some technical and biological constraints can limit translation, and, to the best of our knowledge, no clinical studies have been reported. Full article