Search Results (256)

Background: Pes planus is a condition where the arch of the foot collapses, resulting in the entire sole contacting the ground. The biomechanical implications of pes planus on gait have been widely studied; however, research specific to Black African populations, particularly recreational runners, is scarce. Aim: This study aimed to describe the forefoot centre of pressure (CoP) trajectory during the barefoot gait cycle among Black African recreational runners with pes planus. Methods: A prospective explorative and quantitative study design was employed. Participants included Black African male recreational runners aged 18 to 45 years diagnosed with pes planus. A Freemed™ 6050 force plate was used to collect gait data. Statistical analysis included cross-tabulations to identify patterns. Results: This study included 104 male participants across seven weight categories, with the majority in the 70-to-79 kg range (34.6%, n = 36). Most participants with pes planus showed a neutral foot posture (74.0%, n = 77) on the foot posture index 6 (FPI-6) scale. Flexible pes planus (94.2%, n = 98) was much more common than rigid pes planus (5.8%, n = 6). Lateral displacement of the CoP was observed in the right forefoot (90.4%, n = 94) and left forefoot (57.7%, n = 60). Load distribution patterns differed between feet, with the right foot favouring the medial heel, arch, and metatarsal heads, while the left foot favoured the lateral heel, medial heel, and lateral arch. No statistical significance was found in the cross-tabulations, but notable lateral CoP displacement in the forefoot was observed. Conclusions: The findings challenge the traditional view of pes planus causing overpronation and highlight the need for clinicians to reconsider standard diagnostic and management approaches. Further research is needed to explore the implications of these findings for injury prevention and management in this population. Full article

Silica fume-based geopolymer composite coatings, an approach to using metallurgical solid waste, exert flame retardancy with ecological, halogen-free, and environmentally friendly advantages, but their fire resistance needs to be improved further. Herein, a silica fume-based geopolymer composite flame-retardant coating was designed by doping boric acid (BA), zinc phytate (ZnPA), and melamine (MEL). The results of a cone calorimeter demonstrated that appropriate ZnPA and BA significantly enhanced its flame retardancy, evidenced by the peak heat release rate (p-HRR) decreasing from 268.78 to 118.72 kW·m⁻², the fire performance index (FPI) increasing from 0.59 to 2.83 s·m²·kW⁻¹, and the flame retardancy index increasing from 1.00 to 8.48, respectively. Meanwhile, the in situ-formed boron phosphate (BPO₄) facilitated the residual resilience of the fire-barrier layer. Furthermore, the pyrolysis kinetics indicated that the three-level chemical reactions governed the pyrolysis of the coatings. BPO₄ made the pyrolysis E_α climb from 94.28 (P5) to 127.08 (B3) kJ·mol⁻¹ with temperatures of 731–940 °C, corresponding to improved thermal stability. Consequently, this study explored the synergistic flame-retardant mechanism of silica fume-based geopolymer coatings doped with ZnPA, BA, and MEL, providing an efficient strategy for the high-value-added recycling utilization of silica fume. Full article

The first ray plays a fundamental role in foot biomechanics, particularly in stabilizing the medial longitudinal arch and enabling efficient weight transfer during the mid-stance and propulsion phases of gait. When dorsiflexed—a condition known as metatarsus primus elevatus—especially in its flexible form, this structure disrupts load distribution, impairs propulsion, and contributes to various clinical symptoms. Despite its clinical importance, the biomechanical impact of orthotic elements placed beneath the first ray remains underexplored. This study aimed to quantify the variations in medio-lateral (Fx), antero-posterior (Fy), and vertical (Fz) force vectors generated during gait in response to different orthotic elements positioned under the first ray. A quasi-experimental, post-test design was conducted involving 22 participants (10 men and 12 women) diagnosed with flexible metatarsus primus elevatus. Each participant was evaluated using custom-made insoles incorporating various orthotic elements, while gait data were collected using a dynamometric platform during the mid-stance and propulsion phases. Significant gait-phase-dependent force alterations were observed. A cut-out (E) reduced medio-lateral forces during propulsion (p < 0.05), while a kinetic wedge (F) was correlated with late-stance stability (r = −0.526). The foot posture index (FPI)/body mass index (BMI) mediated the vertical forces. The effect sizes reached 0.45–0.42 for antero-posterior force modulation. Phase-targeted orthoses (a cut-out for propulsion, a kinetic wedge for late stance) and patient factors (FPI/BMI) appear to promote biomechanical efficacy in metatarsus primus elevatus, enabling personalized therapeutic strategies. Full article

As part of the work, polymer composites dedicated to rapid prototyping were developed, especially for 3D printing using the material extrusion technique. For this purpose, a polymer matrix was selected, which was an acrylonitrile-butadiene-styrene (ABS) terpolymer and a flame retardant, which was tetrakis (2,6-dimethylphenyl)-m-phenylenebisphosphate, commercially known as PX200. The effect of the presence and amount (5, 10, 15 and 20 wt.%) of the introduced additive on the rheological properties, structural properties, flammability (limiting oxygen index, LOI; UL94) and flame retardant properties (microcone calorimeter, MLC) of ABS-based composites was investigated. In addition, the mechanism of thermal degradation and flame resistance was investigated using thermogravimetric analysis, TGA and Fourier transform infrared spectroscopy, FT-IR of the residue after the MLC test. In the first part of the work, using the author’s technological line, filaments were obtained from unfilled ABS and its composites. Samples for testing were obtained by 3D printing in Fused Deposition Modeling (FDM) technology. In order to determine the quantitative and qualitative spread of fire and the effectiveness of the phosphorus flame retardant PX200 in the produced composites, the Maximum Average Rate of Heat Emission (MARHE); Fire Growth Rate Index (FIGRA); Fire Potential Index (FPI) and Flame Retardancy Index (FRI) were determined. Based on the obtained results, it was found that the aryl biphosphate used in this work exhibits activity in the gas phase, which was confirmed by quantitative assessment using data from a microcone calorimeter and non-residues after combustion and thermolysis at 700 °C. As a result, the flammability class did not change (HB40), and the LOI slightly increased to 20% for the composite with 20% flame retardant content. Moreover, this composite was characterized by the following flammability indices: pHRR = 482.9 kW/m² (−40.3%), MARHE = 234 kW/m² (−40.7%), FIGRA = 3.1 kW/m²·s (−56.3%), FPI = 0.061 m²·s/kW (+64.9%), FRI = 2.068 (+106.8%). Full article

A dual-parameter optical fiber sensor for measuring the magnetic field and temperature based on the Fabry–Perot interferometer (FPI) and magnetic polymer film was proposed and designed, realizing dual-parameter measurement of temperature and the magnetic field. The sensor uses the excellent elasticity and thermal expansion coefficient of PDMS and the magnetostrictive effect of Fe₃O₄ magnetic polymer film to provide magnetic field and temperature detection while maintaining good reusability, achieving a magnetic field sensitivity and temperature sensitivity of 69 pm/mT and 390 pm/K, respectively. The sensor has the advantages of a low cost, a simple manufacturing process, good linearity, and a sensitive temperature response. It has broad application prospects in medicine, geography, aerospace, and other fields. Full article

This study investigates the impact of physical and financial infrastructure on the dynamics of net total capital flows in BRICS economies over the period 2010–2024. Using panel data and a fixed-effects regression model with robust standard errors, it analyzes how infrastructure quality, both physical (transport, energy, and telecommunications) and financial (banking systems, capital markets, and regulation), affects private capital inflows. The results show a statistically significant positive relationship, with physical infrastructure reducing business costs and financial infrastructure improving capital allocation and investor confidence. This paper contributes novel empirical evidence linking infrastructure systems with capital flow dynamics, providing key insights for policymakers aiming to enhance resilience and attract sustainable private investment. Full article

Aiming to mitigate engineering risks such as tunnel face collapse and equipment jamming caused by poor geological conditions during the construction of tunnel boring machines (TBMs), this study proposes a TBM surrounding rock grade prediction method based on multi-source feature fusion. Firstly, a multi-source dataset is established by systematically integrating TBM tunnelling parameters, horizontal acoustic profile (HSP) detection data and three-dimensional geological spatial information. In the data preprocessing stage, the TBM data is cleaned and divided according to the mileage section, the statistical characteristics of key tunnelling parameters (thrust, torque, penetration, etc.) are extracted, and the rock fragmentation index (TPI, FPI, WR) is fused to construct a composite feature vector. The Direct-LiNGAM causal discovery algorithm is innovatively introduced to analyse the nonlinear correlation mechanism between multi-source features, and then a hybrid model, TRNet, which combines the local feature extraction ability of convolutional neural networks and the nonlinear approximation advantages of Kolmogorov–Arnold networks, is constructed. Verified by a real tunnel project in western Sichuan, China, the prediction accuracy of TRNet for surrounding rock grade on the test set reaches an average of 92.15%, which is higher than other data-driven methods. The results show that the prediction method proposed in this paper can effectively predict the surrounding rock grade of the tunnel face during TBM tunnelling, and provide decision support for the dynamic regulation of tunnelling parameters. Full article

With the continued advancement of shale gas development, the issue of frac hit has become increasingly prominent and has emerged as a key factor influencing the production of shale gas wells. Quantitative evaluation of the impact of frac hit on shale gas wells and proposing different methods to prevent frac hit are of great significance for the efficient development of shale gas. This research puts forward a machine learning-based workflow that incorporates geological and engineering factors to evaluate the impacts of frac hit. The “Frac Hit Pressure Integral Index (FPI)” quantifies the dynamic pressure responses by means of the ratios of initial pressure to shut-in pressure. Pearson analysis is employed to reduce the dimensionality of parameters, and Random Forest and K-means++ algorithms are utilized to classify the risks of frac hit. Among numerous influencing factors, it has been found that the brittleness index and well spacing possess the highest weights among the geological and engineering influencing factors, reaching 20.4 and 16.1, respectively. The L well area of southern Sichuan shale gas lies in the Fuji syncline of the Huaying Mountain tectonic system’s low-fold Fujian zone. When applied to the L well area in the Sichuan Basin, the results pinpoint the brittleness index, fluid intensity, and well spacing as crucial factors. It is recommended that, for reservoirs with high fracturability, reducing fluid intensity and increasing well spacing can minimize inter-well interference. This workflow classifies risks into low (FPI ≤ 265.43), medium (265.43 < FPI < 658.56), and high levels (FPI ≥ 658.56) and recalibrates natural fracture zones based on pressure and flowback data, thereby enhancing the alignment between geological and engineering aspects by 10%. This framework optimizes fracturing designs and mitigates inter-well interference, providing support for the efficient development of shale gas. Full article

Fluorinated polyimide (FPI), renowned for its exceptional low-dielectric properties, colorless transparency, high-temperature resistance, and flexibility, has emerged as an ideal material for addressing challenges in 5G/6G high-frequency signal transmission and flexible electronic substrates. Nevertheless, the structure–property relationship between molecular architectures and the dielectric characteristics of FPI films remains insufficiently understood, necessitating urgent elucidation of the underlying mechanisms. In this study, a diamine monomer containing bis-amide bonds, 4-amino-N-{4-[(4-aminobenzoyl)amino]phenyl}benzamide (PABA), was synthesized. Subsequently, six FPI films (FPAIs, FPEIs, and FPEsIs) with distinct structural features were prepared through homopolymerization of PABA and five other diamines (containing amide bonds, ether, and ester groups) with fluorinated dianhydride (6FDA). Systematic characterization of thermal, mechanical, optical, and dielectric properties revealed that these films exhibit excellent thermal stability (T_g: 296–388 °C), mechanical strength (σ: 152.5–248.1 MPa, E: 2.1–3.4 GPa), and optical transparency (T_{550 nm}: 82–86%). Notably, they demonstrated a low dielectric constant (D_k as low as 2.8) and dielectric loss (D_f down to 0.002) under both low- and high-frequency electric fields. Furthermore, molecular dynamics simulations and quantum chemical were employed to calculate critical physical parameters and HOMO–LUMO energy levels of the six FPIs. This computational analysis provides deeper insights into the structure–performance correlations governing dielectric behavior and optical transparency in FPIs. The findings establish valuable theoretical guidance for designing advanced PI films with tailored dielectric properties and high transparency. Full article

Floods result from intense and/or prolonged rainfall that exceeds the soil’s infiltration capacity, generating surface runoff and increasing river discharge. These events can cause substantial societal damage and may even lead to fatalities. In this study, we analyzed flood events in Lençóis Paulista, southeastern Brazil, between 2016 and 2024, by evaluating estimated precipitation and soil moisture conditions to develop a flood prediction index for the city. Precipitation estimates were derived from reflectivity data provided by the Bauru weather radar, while soil moisture estimates were obtained from the Joint UK Land Environment Simulator (JULES) land surface model, operated at IPMet-Unesp. Although the index was not developed based on formal hydrological modeling or physical process simulation, the analysis of these variables within the Lençóis River sub-basins revealed that elevated soil moisture in the days preceding flood events was a key contributing factor. This is consistent with the increased susceptibility of wetter soils to surface runoff generation. Based on the identification of relevant variables, we developed the Flood Probability Index (FPI) using data from only nine flood events and applied it to classify the likelihood of flooding in the city. The index produced satisfactory results, highlighting its potential as a tool for flood prediction and early warning for the local population. Full article

Background/Objectives: The foot posture index (FPI-6) is a practical clinical tool for evaluating standing foot posture using six specific criteria. Although widely used, its reliability and correlation with radiographic parameters remain uncertain. This study aimed to assess the inter-rater reliability of the FPI-6, in both asymptomatic individuals and patients with foot and ankle symptoms, and to examine its correlation with radiographic measurements. Methods: We included 40 asymptomatic male volunteers (group A) and 60 symptomatic patients (group B). Four raters independently assessed the FPI-6 scores, and inter-rater reliability was evaluated using the intraclass correlation coefficient. Radiographic parameters included the talocalcaneal angle (TCA) on anteroposterior (AP) and lateral views, talonavicular coverage angle (TNCA), AP talo-first metatarsal angle (TMA), hindfoot alignment angle (HAA), calcaneal pitch angle (CPA), and Meary’s angle (MA). Correlations between the FPI-6 and radiographic measurements were analyzed using Pearson’s correlation (r). Results: The FPI-6 showed good to excellent inter-rater reliability in both groups, with higher consistency in group B and among experienced raters. The total FPI-6 score significantly correlated with TNCA (r = 0.665), AP TMA (r = 0.453), lateral TCA (r = 0.369), MA (r = 0.570), and HAA (r = −0.773) (all p < 0.001). Group B demonstrated overall stronger correlations between the FPI-6 and radiographic measurements compared to group A (TNCA: 0.664 vs. 0.258; AP TMA: 0.542 vs. 0.139; lateral TCA: 0.492 vs. −0.101; MA: 0.544 vs. 0.172; and HAA: −0.712 vs. −0.374). Conclusions: With careful application, the FPI-6 is a reliable and valid tool for clinical assessment of foot posture, especially in settings without immediate access to radiographs. Full article

Acute and chronic Food Protein-Induced Enterocolitis Syndrome (FPIES) has been well characterized in children; otherwise, neonatal FPIES (N-FPIES) remains poorly understood. In terms of pathophysiology, neonatal FPIES appears to have a more prevalent TH2 response and is characterized by specific clinical features that make the diagnosis challenging. Genetic and environmental risk factors may predispose to the development of FPIES. Recent evidence indicates that a characteristic microbiota signature may lead to barrier dysfunction, reduced regulatory T cells, and abnormal intestinal production of serotonin, responsible for the symptoms of FPIES. Regarding clinical presentation, newborns with FPIES may not fully meet the current guideline’s diagnostic criteria at disease onset, being more similar to clinical entity specific of neonatal age than to acute FPIES in infants and children. Hence, differentiation from other neonatal medical and surgical conditions—particularly necrotizing enterocolitis (NEC)—remains a critical challenge for clinicians. This present review highlights our current understanding of N-FPIES, in term of pathophysiology, clinical presentation diagnosis, and treatment strategies. Refining diagnostic criteria for N-FPIES represents a clinical priority to help physicians in diagnosing and managing this challenging condition. Last, but not least, larger clinical trials are needed to optimize treatment practices in term and preterm newborns with FPIES. Full article

Groundwater is one of the major sources of freshwater supply for drinking and domestic purposes. This study evaluates the hydrogeochemical processes, groundwater quality for human consumption, associated health risks from fluoride F⁻ and nitrate (NO₃⁻), and sources of dissolved solutes in a highland watershed in northern Pakistan. Groundwater samples (n = 51) were gathered and analyzed for a range of physicochemical parameters. To evaluate contamination, indices such as the nitrate pollution index (NPI) and fluoride pollution index (FPI) were applied, along with a composite groundwater pollution index to assess overall water quality. The findings revealed that total dissolved solid, turbidity, F⁻, and K⁺ levels exceeded health-based thresholds in 20%, 1%, 4%, and 2% of samples, respectively. Among the water sources, handpumps were identified as the most contaminated. According to the NPI and composite index, 96% and 92% of the samples did not show significant contamination, respectively. However, the FPI results highlighted that 59% of the samples exhibited low F⁻ pollution, while 41% fell under medium pollution levels. While NO₃⁻ ingestion posed no notable health risks, ${\mathrm{F}}^{-}$ exposure presented significant concerns, with 58.8% of the samples posing risks, particularly for children. The dominant hydrochemical facies were Ca-Mg-HCO₃, with the main influence on water chemistry by rock-water interactions and reverse ion exchange processes. Full article

Over the past quarter-century, the enhanced availability of satellite imagery, characterized by improved temporal, spectral, radiometric, and spatial resolutions, has enabled valuable insights into the spatial soil variability of annual croplands and orchards. This study investigates the impact of spatial resolution on classifying three-year, multi-temporal vegetation indices derived from satellites with coarse (30 m, Landsat 8), medium (10 m, Sentinel-2), and fine spatial resolutions (3.7 m, PlanetScope). The classification was performed using the fuzzy c-means algorithm, with the fuzziness performance index (FPI) and normalized classification entropy (NCE), which were used to determine the optimal number of management zones (MZs). Our results revealed that the Landsat 8-based NDVI images produced the highest number of clusters (nine for annual cropland and six for orchards), while the finer resolutions from PlanetScope reduced this to three clusters for both cultivation types, more accurately capturing the intra-parcel variability. Except for Landsat 8, the NDVI means of MZs generated based on Sentinel-2 and PlanetScope using the fuzzy c-means algorithm showed statistically significant differences from each other, as determined by a one-way and Welch’s ANOVA (p < 0.05). The use of PlanetScope imagery demonstrated its superiority in generating zones that reflect inherent variability, offering farmers actionable insights at a reconnaissance scale. Multi-temporal satellite imagery has proved effective in monitoring plant growth responses to edaphological soil properties. In our study, the PlanetScope satellites, which offer the highest spatial resolution, consistently produced effective zones for orchard areas. These zones have the potential to enhance farmers’ discovery of knowledge at a reconnaissance scale. With the increasing spatial resolution and enhanced spectral resolution of newer satellite sensors, using cluster analysis with insights from soil scientists promise to help farmers better understand and manage the fertility of their fields in a cost-effective manner. Full article

Background/Objectives: Pediatric patients with non-IgE-mediated gastrointestinal food allergies (non-IgE-GIFAs) may experience alterations of nutritional status. This non-randomized, prospective intervention study investigated the impact of dietary counseling on nutritional status in pediatric patients with non-IgE-GIFAs. Methods: Patients of both sexes aged 0–14 years newly diagnosed with non-IgE-GIFAs received dietary counseling provided by certified pediatric dietitians immediately after diagnosis. Nutritional status parameters were assessed to identify nutritional status alterations at baseline and after 12 months of intervention (T12). Results: The study included 100 patients (58% male, mean age 8.5 ± 8.8 months). Non-IgE-GIFAs phenotypes included food protein-induced enteropathy (FPE, 44%), food protein-induced enterocolitis syndrome (FPIES, 11%), food protein-induced allergic proctocolitis (FPIAP, 17%), and food protein-induced motility disorders (FPIMD, 28%). At diagnosis, 1% was affected by obesity (1 FPIAP), 5% were affected by overweight (2 FPE, 1 FPIAP, and 2 FPIMD), 7% were moderately underweight (5 FPE and 2 FPIMD), 1% was severely underweight (1 FPE), 7% were moderately stunted (4 FPE, 1 FPIAP, and 2 FPIMD), 16% were moderately wasted (11 FPE, 1 FPIES, 1 FPIAP, and 3 FPIMD), and 4% were severely wasted (2 FPE and 2 FPIMD). At T12, improvements in anthropometric parameters were observed, along with a reduction in the prevalence of malnutrition by excess (6% at diagnosis vs. 2% at T12) and a reduction in the undernutrition subtypes rate, including underweight, stunting, and wasting (26% at diagnosis vs. 3% at T12, p < 0.001). Conclusions: Non-IgE-GIFAs can negatively impact the nutritional status of pediatric patients. Thus, dietary counseling could be an effective strategy for preventing and managing nutritional alterations in these patients. Full article