Search Results (21,358)

Construction materials like steel and concrete have been used for thousands of years; however, their industrial-scale production began relatively recently in the 19th century. These materials are still being improved as the drive to build taller buildings, longer bridges, larger dams, and similar engineering marvels keeps pushing boundaries and requirements to previously unimaginable values. Yet, testing and characterization of construction materials that make all that progress possible are overshadowed in scientific literature by more trendy materials such as graphene, composites, nanomaterials, smart materials, and biomaterials. The objective of this review was to identify, collect, and systematically analyze recent papers in which the researchers performed experimental testing on construction materials to document how state-of-the-art experimental practice extends beyond what standardized protocols prescribe. This paper covers Uniaxial Tensile Testing (UT), Compact Tension C(T), Uniaxial Compression (UC), and Single Edge Notched Bending SEN(B), as they are the most commonly used and best-suited techniques for construction material analysis. State-of-the-art papers featuring these techniques were systematically gathered using AI-assisted literature discovery tools, and their contributions beyond ISO and ASTM standards were identified and summarized. Using this review, material scientists and engineers can quickly discover the most influential and relevant papers with the actual experimental data and can apply the testing procedures described in these papers in their laboratories so they can compare their results with the previously published measurements and make an engineering decision based on appropriate comparisons. Full article

Background/Objectives: Early-life environment may influence long-term neurodevelopment through epigenetic regulation. Serotonergic and glutamatergic pathways are central to brain development and have been implicated in DNA methylation changes following prenatal adversity. In this study, we examined whether preterm birth (PTB) in birthweight-discordant twins is associated with differential DNA methylation in the serotonin receptor signaling pathway and the glutamatergic synapse pathway in adult twins. Methods: Genome-wide DNA methylation data were obtained from whole blood samples of 288 individuals (144 monozygotic birthweight-discordant twin pairs), including a younger cohort (140 individuals; mean age 33 years) and an older cohort (148 individuals; mean age 63 years). DNA methylation was measured using the Illumina HumanMethylation450 BeadChip. Linear models were fitted for association testing, adjusting for leukocyte composition and twin pair correlation. Pathway-level differential methylation was assessed using Rotation Gene Set Testing. Results: In the glutamatergic synapse pathway, no consistent directional enrichment of hypo- or hypermethylation was observed. However, gene-level analyses identified consistent hypomethylation of GRIA2 and GRIA4 across cohorts. In the serotonin receptor signaling pathway, the young cohort exhibited a mixed methylation pattern, whereas the old cohort showed significant enrichment of hypermethylation. At the gene level, HTR1A was hypomethylated in the young cohort but hypermethylated in the old cohort, indicating a cohort-dependent effect in the methylation patterns. Conclusions: These findings suggest that PTB is associated with long-term epigenetic variation in neurodevelopmentally relevant pathways, as reflected in blood cells. The results further indicate distinct methylation architectures across pathways, with more consistent pathway-level signals in the serotonergic system and more localized gene-level effects in the glutamatergic pathway. Full article

Post-rotation jacking is a critical construction stage for load-path reconstruction and alignment adjustment in rotation-constructed bridges, particularly for ultra-wide double-deck composite girder systems. Taking a two-span continuous steel truss–concrete composite girder bridge with spans of 2 × 85 m as the engineering background, this study investigates the mechanical behavior during post-rotation jacking through theoretical derivation, finite element simulation, and on-site monitoring. Based on the force method of structural mechanics, a linear relationship between vertical synchronous jacking force and displacement is derived, and an analytical formulation for bearing reaction redistribution under laterally asynchronous jacking is established by considering the coupling effects of vertical bending, torsion, and transverse multi-bearing support. A full-bridge spatial finite element model was developed in MIDAS Civil NX 2024 V1.1 to analyze the redistribution of bearing reactions and the stress response of the concrete crossbeam under different jacking conditions. The results show that, for the investigated bridge, the jacking force–displacement response remains highly linear during synchronous jacking. The B-axis middle bearing is more sensitive to jacking displacement than the two side bearings, with its fitted stiffness being approximately 2.19 times the average stiffness of the side bearings. Eccentric jacking causes reaction concentration at the jacked point and reaction reduction at adjacent supports, and the magnitude of reaction variation increases approximately linearly with jacking displacement. When the transverse non-uniform jacking magnitude reaches 20 mm, a tensile stress of 0.3 MPa appears at the bottom flange of the concrete crossbeam; therefore, a project-specific stroke-difference limit of 20 mm is recommended for this bridge, while the actual construction achieved a stroke control accuracy of ±0.5 mm and a transverse elevation difference within 1 mm. Field monitoring results validate the proposed analytical and numerical methods. The Pearson correlation coefficients of the measured jacking forces with the finite element and theoretical results are 0.9987 and 0.9988, respectively, and the corresponding mean relative errors are 3.84% and 4.23%. For stress responses, the measured and calculated values show a strong correlation, with a Pearson correlation coefficient of 0.9980 and a mean relative error of 12.77%; the critical mid-span monitoring point shows a relative error of only 0.65%. The final bridge alignment deviation is controlled within ±3 cm. The overall mean verification coefficient is 0.968, with a 95% empirical agreement range of [0.888, 1.048], indicating that the proposed mechanical analysis framework and combined force–displacement control strategy can provide a useful reference for refined construction control of similar ultra-wide double-deck composite girder bridges with comparable span arrangement and transverse bearing layout. Full article

Ornamental fountains in the Alhambra and Generalife (Granada, Spain) constitute complex socio-ecological systems where water, stone, and biological communities interact, making them highly vulnerable to biodeterioration caused by phototrophic microorganisms such as cyanobacteria, green algae, and diatoms. Conventional chemical biocides, although widely applied, present significant drawbacks including toxicity, material degradation, ecological imbalance, and limited long-term effectiveness. In this context, this study evaluated the potential of algicidal bacteria as a sustainable alternative for controlling phototrophic growth in heritage environments. Water samples from eight ornamental fountains were analyzed using 16S ribosomal RNA (16S rRNA) gene sequencing to characterize bacterial communities and identify taxa previously reported with algicidal activity. Statistical analyses were conducted to assess relationships between microbial community structure and biofilm development. In parallel, functional screening assays using filtered fountain waters against Chlorella vulgaris were performed to evaluate intrinsic inhibitory capacity. The most active sample was selected for bacterial isolation and further validation through co-culture assays, cell density measurements, and pulse-amplitude-modulated (PAM) fluorometry. A total of 18 genera with reported algicidal capacity were detected, representing a substantial fraction of the microbiome across all samples. However, no significant association was found between these taxonomic metrics and biofilm development, highlighting a decoupling between taxonomic composition and functional activity. The most active isolate, identified as Stenotrophomonas maltophilia strain LIG25, caused a rapid decline in photosynthetic efficiency and achieved more than 98% inhibition of algal growth. These findings demonstrate that ornamental fountain microbiomes represent a reservoir of native biocontrol agents and support the development of eco-friendly strategies for cultural heritage conservation. Full article

Multi-field coupled numerical analysis and strain monitoring experiments were conducted for the curing process of a ring-shaped CFRP component. The curing kinetics and mechanical properties of LD-2184 epoxy resin were characterized using non-isothermal DSC, tensile testing, and CTE measurements. The curing reaction follows a single-stage autocatalytic mechanism with an activation energy of 54.73 kJ·mol⁻¹. A piecewise curing kinetics equation was established. The elastic modulus of the fully cured resin is 2.810 GPa, and the coefficient of thermal expansion is 6.060 × 10⁻⁵ K⁻¹. Composite ring specimens were fabricated using a wet winding process. FBG sensors were embedded to monitor axial strain during curing. A coupled numerical model was developed that includes heat conduction, curing kinetics, and curing deformation. ABAQUS was used to simulate the curing process of the composite ring. The results show a temperature gradient within the filament-wound layer. Thermo-chemical strain is similar between inner and outer regions. Total strain varies along the thickness due to mold constraint. Residual stress is governed by resin chemical shrinkage and thermal contraction during cooling. The difference between measured and simulated strain is 7.15%, which supports the validity of the multi-field coupled curing model. Full article

Melamine, characterized by its high nitrogen content, has been illegally added to food and feed to falsely increase apparent protein levels. However, melamine and its metabolites pose serious risks to human and animal health, including kidney stones, renal failure, and even death, as well as potential carcinogenic effects. Therefore, accurate detection of trace melamine is of great importance and urgency. Electrochemical sensors based on nanomaterials have been widely used for melamine detection due to their high sensitivity, good selectivity, rapid response, and simple operation. In this work, a composite nanosheet-structured electrode was fabricated, and a dense layer of gold nanoparticles was modified on its surface to enhance electrochemical performance. Cyclic voltammetry and electrochemical impedance spectroscopy measurements indicated that this electrode exhibited highly sensitive electrochemical properties. In addition, differential pulse voltammetry was employed for melamine detection, and the results showed a wide linear range of 20–500 nM with an LOD of 4.7 nM. The proposed electrode enabled the detection of melamine in milk samples, exhibiting good anti-interference ability and long-term stability. Full article

This study reports the physicochemical characterization and structure–property relationships of rigid sheep wool/phenolic novolac panels developed as bio-based thermal insulation for building envelopes. Mixed Polish sheep wool was washed, mechanically opened, and formed into nonwoven mats, then impregnated with either neat or flame-retardant novolac resin to obtain lightweight boards with a fiber content of about 50 wt%. Elemental analysis, ICP-OES, FTIR spectroscopy, and laser and electron microscopy were used to evaluate the fiber composition, keratin structure, morphology, and fiber–matrix interfaces. Mechanical performance under three-point bending and shear, differential scanning calorimetry, thermogravimetric analysis, and transient hot-probe thermal-conductivity measurements were applied to link microstructure with functional behavior. Novolac impregnation transformed the compliant wool mat into self-supporting panels, increasing the flexural modulus to the 0.8–1.4 GPa range and flexural strength to approximately 48–52 MPa, while the shear modulus and work to failure rose by more than an order of magnitude relative to the loose wool reference. Thermal conductivity remained in a typical range for natural-fiber insulations (λ = 0.061 W·m⁻¹·K⁻¹ for the wool mat and 0.071–0.074 W·m⁻¹·K⁻¹ for the composites), although higher than that of expanded polystyrene. DSC and TGA confirmed that wool fibers remain thermally stable up to about 200–220 °C, that the novolac resin cures around 140 °C, with typical phenolic reaction enthalpies, and that both formulations generate high char residues of roughly 60–80 wt% at 600 °C under nitrogen, evidencing a strong charring propensity rather than directly quantifying fire resistance. Overall, the results position sheep wool/novolac panels between conventional bio-based insulation and structural composites and highlight their potential as sustainable, circular insulation materials for energy-efficient building envelopes. Full article

We develop an analytical framework to describe the impact of in-plane strain on the electronic and transport properties of graphene. Starting from a strain-modified nearest-neighbor tight-binding model, we derive the energy spectrum and group velocities, explicitly incorporating bond-dependent hopping renormalization. A dimensionless anisotropy parameter, derived from velocity fluctuations, is introduced to quantify directional transport imbalance. We show that this parameter admits a closed-form expression entirely determined by the strain tensor, linking lattice deformation directly to measurable transport quantities. In the small-strain regime, a compact expression is obtained, $\eta \approx ϵ\left(1+\nu \right)\cos \left(2\theta \right)$, revealing an angular dependence controlled solely by the orientation of the applied deformation. This establishes that strain acts as a purely geometric control parameter, separating magnitude and orientation effects. Within the semiclassical Boltzmann framework, the same parameter fully determines the conductivity tensor, leading to simple expressions for the longitudinal components ${\sigma }_{x,y}={\sigma }_0\left(1\mp \eta \right)$ and a clear identification of the preferred transport direction. Importantly, the total conductivity remains constant, while strain redistributes transport between orthogonal directions. These results provide a transparent and predictive description of strain-induced transport anisotropy, demonstrating that the directional electronic response can be tuned without modifying the material composition, offering a practical route to control electronic response in graphene through purely mechanical means. Full article

This study investigates the development of a functional hummus enriched with black cumin seed oil (Nigella sativa) and evaluates its physicochemical properties and oxidative stability during 21 days of refrigerated storage. Additionally, the applicability of near-infrared (NIR) spectroscopy as a rapid and non-destructive analytical tool for hummus quality assessment was examined. Hummus samples were prepared by partially replacing olive oil with black cumin seed oil at levels of 4, 6, 8, and 12% (v/v). Chemical composition, peroxide value, and water activity were monitored over time, while multivariate statistical methods (Principal Component Analysis and Partial Least Squares Regression) were used to correlate NIR spectral data with reference measurements. The results showed that the incorporation of black cumin seed oil did not significantly affect the overall macronutrient composition but altered the fatty acid profile by increasing the content of polyunsaturated fatty acids. Oxidative changes were observed during storage, with peroxide values increasing after day 7, while samples with higher levels of black cumin seed oil exhibited improved oxidative stability in later stages. Water activity remained constant across all formulations. NIR spectroscopy demonstrated high predictive accuracy for fat, protein, carbohydrate, and dietary fiber content (R² > 0.99), while lower performance was observed for water activity and dry matter. The findings confirm the potential of NIR spectroscopy for rapid quality monitoring of functional plant-based spreads. This study highlights the feasibility of developing a functional hummus enriched with black cumin seed oil and supports the application of NIR spectroscopy as an efficient tool for monitoring compositional and oxidative changes during storage. Full article

Biological nitrogen fixation (BNF) is an important trait in soybean (Glycine max L. Merr.) because it reduces dependence on synthetic N fertilizers and supports sustainable crop production; however, field-based phenotyping methods for evaluating BNF-associated performance are often laborious, costly, and difficult to apply to large germplasm populations. Here, we developed a retention-based phenotyping protocol using 194 soybean accessions from maturity groups III–VII evaluated under non-N-applied (N−) and N-applied (N+) field conditions during two growing seasons. Canopy chlorophyll content was monitored using SPAD measurements, whereas 1000-seed weight and seed protein concentration were determined at harvest. Trait performance under N− conditions was normalized relative to N+ conditions using retention values. Mean SPAD retention, 1000-seed weight retention, and protein concentration retention were integrated into a Composite Retention Index (CRI) to classify accessions across contrasting N environments. Indeed, CRI effectively separated accessions into three tiers (high, intermediate, and low retention) and captured variation in canopy chlorophyll retention, 1000-seed-weight retention, and protein concentration retention. Overall, the proposed protocol provides a practical, economical, and reproducible field-based approach for identifying soybean accessions with superior BNF-associated performance and may serve as a useful phenotyping tool in genetic improvement programs. Full article

Background: Nutritional therapy is central in the management of chronic kidney disease (CKD) and cancer, yet these conditions impose partially conflicting requirements. The 2024 KDIGO guideline recommends a controlled protein intake (~0.8 g/kg/day) to reduce metabolic burden in non-dialysis CKD patients, whereas the ESPEN (European Society for Clinical Nutrition and Metabolism) guidelines support higher protein intake (≥1.0–1.5 g/kg/day) to prevent cancer-related malnutrition. Evidence guiding patients affected by both conditions is limited. We evaluated the effects of a Mediterranean-like controlled protein diet in onconephrological patients compared with CKD controls. Methods: In this retrospective study, 358 CKD patients (183 onconephrological, 175 controls) were followed at a tertiary center (2017–2024). Patients received a protein-controlled diet (0.6–1.0 g/kg/day) tailored to comorbidities and nutritional status. Nutritional assessment included bioelectrical impedance analysis and anthropometry. Renal function was evaluated using creatinine and cystatin C, and measured GFR by iohexol clearance at baseline and 12 months. Results: Baseline body composition was comparable between groups. After intervention, serum urea significantly decreased in both groups, without a decline in measured or estimated GFR. Fat mass and central adiposity indices were reduced, while lean mass and phase angle remained stable. No evidence of protein–energy wasting or catabolic activation emerged. Longitudinal analyses showed no significant time × cancer interaction for renal function or most bioimpedance-derived body composition parameters. However, at extended follow-up, arm circumference and tricipital skinfold thickness showed significant time × cancer interactions, suggesting different longer-term peripheral anthropometric trajectories according to cancer status. Conclusions: In this retrospective real-world cohort, structured nephro-nutritional management with an individualized Mediterranean-like controlled protein prescription was associated with preserved renal function and no evidence of overt nutritional deterioration in onconephrological patients. These findings support the feasibility and apparent safety of this approach in selected patients, while highlighting the need for prospective studies with objective dietary adherence assessment and longer-term evaluation of cancer-related anthropometric trajectories. Full article

The contact performance of automotive airbag electrical connectors directly affects the stable conduction of the initiator circuit, yet sufficient failure data are difficult to obtain for such long-life safety-critical components. This study develops a degradation model for connectors with stainless-steel pins, beryllium-bronze sockets, and Ni/Au composite coatings, using the contact resistance increment as the degradation measure. Considering the accumulation of oxidation corrosion products under thermal stress, as well as the local film rupture and re-oxidation induced by fretting wear under combined temperature-vibration stress, a nonlinear time scale t^α is introduced to describe the nonlinear growth of contact resistance. A random-drift nonlinear Wiener process is then constructed: the diffusion term represents local fluctuations within each sample trajectory, while the random drift rate captures growth-rate differences among samples. Parameter estimation was performed using degradation data obtained from 160 °C high-temperature and 160 °C temperature-vibration accelerated degradation tests. The estimation results show that the stress-class-specific time-scale model better reflects the different degradation mechanisms than a common time-scale model, and that the temperature-vibration group exhibits higher resistance growth and stronger trajectory fluctuations. Model diagnostics support the description of the main increment distribution and sample-to-sample differences, while EDS and XPS results provide supplementary evidence for oxidation-related surface composition changes and coating-state evolution. Full article

Background/Objectives: Orthodontic treatment induces controlled mechanical forces that alter the periodontal environment, including changes in oral microbiota composition and activation of local inflammatory pathways. Despite the widespread and growing use of orthodontic appliances across all age groups, the magnitude, timing, and multi-domain biological impact of these changes have not been comprehensively quantified in a single systematic synthesis. This systematic review and meta-analysis aimed to synthesize the available evidence on periodontal clinical parameters, oral microbiota composition, and local inflammatory biomarkers associated with orthodontic treatment using fixed appliances and clear aligners, and to provide a structured, GRADE-rated evidence base for clinical practice. Methods: A systematic review and meta-analysis was conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, and Web of Science were searched from inception to March 2026. Prospective cohort studies, longitudinal clinical studies, and randomized controlled trials evaluating periodontal parameters, oral microbiota, and inflammatory biomarkers during orthodontic treatment were included. Quantitative synthesis was performed using mean differences or standardized mean differences with 95% confidence intervals, primarily assessing within-group (pre–post) changes. Results: Eighteen studies (n = 812 patients; follow-up 3–12 months) met inclusion criteria. Fixed orthodontic appliances were consistently associated with transient increases in plaque index (MD 0.45, 95% CI 0.32–0.58; I² = 62%), gingival index (MD 0.38, 95% CI 0.25–0.51; I² = 55%), and bleeding on probing (MD 15.2%, 95% CI 10.1–20.3%; I² = 48%), particularly during early treatment phases. Microbiological analyses demonstrated within-group shifts toward increased prevalence of periodontopathogenic species (Streptococcus mutans OR 2.45, 95% CI 1.89–3.18; Porphyromonas spp. OR 2.14, 95% CI 1.67–2.75) in patients treated with fixed appliances. Local inflammatory responses were characterized by elevated IL-1β (MD 1.2, 95% CI 0.8–1.6) and IL-6 (MD 0.9, 95% CI 0.6–1.2) in gingival crevicular fluid. Certainty of evidence was rated moderate for plaque and gingival indices and low for microbiological and inflammatory outcomes (GRADE). Conclusions: Orthodontic treatment—particularly with fixed appliances—is associated with transient, reversible deterioration of periodontal indices, shifts toward a more dysbiotic oral microbiome, and elevation of local inflammatory mediators in gingival crevicular fluid during active treatment phases. These changes are manageable through structured preventive protocols and regular periodontal monitoring. Future prospective studies with concurrent control groups and standardized multi-domain outcome measures are needed to better define the magnitude and reversibility of these biological responses. PROSPERO: CRD420261336117. Full article

Air pollution is a major environmental and public health issue, largely driven by human activities. The present study evaluates the combined use of two bioindicators from different taxonomic groups, the moss Rhytidiadelphus squarrosus and the terrestrial snail Cornu aspersum, to assess early biological effects induced by atmospheric exposure to toxic elements. Both species, chosen for their sensitivity, simple physiology, and suitability for field transplantation, were exposed for 30 days at two sites in southern Italy with contrasting environmental conditions. Toxic element accumulation in moss biomass and snail tissues was measured using ICP-OES, while snail shell composition was analyzed using FTIR spectroscopy. Biological responses were assessed through oxidative stress biomarkers (ROS levels and catalase activity), HSP70 expression determined by Western blotting, and structural damage, including ultrastructural changes in mosses and histopathological alterations in snails. Results showed site-dependent patterns of toxic elements accumulation in both organisms, consistent with increased oxidative stress and induction of HSP70 expression. Enlargement of the albumen gland and histological alterations in digestive tubules and reproductive systems were found in snails. Mosses showed severe ultrastructural alterations. FTIR analysis revealed changes in snail shell composition consistent with metal exposure. Principal component analysis highlighted clear patterns linking contamination, oxidative stress, and structural damage, supporting the complementarity of the two bioindicators and their ability to capture distinct exposure pathways and biological effects. Full article

The study investigates Co²⁺/M⁴⁺ (Sn, Zr, Hf)-substituted M-type barium ferrites to understand phase formation, structural evolution and magnetic behavior. Ferrites with the general composition BaFe_12−x−yCo_xM_yO₁₉ were synthesized via sodium carbonate flux and analyzed using powder and single-crystal X-ray diffraction, wavelength dispersive X-ray spectroscopy, X-ray absorption spectroscopy and magnetic measurements. Structural analysis showed increasing lattice parameters with increasing degree of substitution, confirming incorporation of the substituting tetravalent metals. Differing maximum substitution levels were determined for the different systems, with wavelength dispersive X-ray spectroscopy providing the most reliable compositional data. A slight excess of the tetravalent metals Sn⁴⁺, Zr⁴⁺ and Hf⁴⁺ relative to Co²⁺ was frequently observed. X-ray absorption spectroscopy and wavelength dispersive X-ray spectroscopy analyses indicated negligible Fe²⁺ formation and no clear trends for formation of vacancies. Site occupancy analysis assigned tetravalent cations primarily to the Fe(4) site (4f₂), with evidence that cobalt partially occupies the Fe(3) site (4f₁). Magnetic measurements revealed decreasing saturation magnetization, remanence and coercivity at room temperature with increasing substitution level, while low-temperature measurements showed enhanced remanence and coercivity. Full article