Search Results (41,288)

The mechanical behavior of bamboo scrimber dowel-bearing under sustained loading was investigated via the Stepped Isothermal Creep Deformation (SICD) method using a 30-ton multi-field coupling system, with the test conducted over a duration of 51.5 h. Experimental results revealed three typical failure modes: material failure, local compression failure, and crushing failure. The damage degree increased linearly with stress level. SEM microstructural analysis further indicated that failure originated from progressive fracture and bending of fiber bundles, as well as layer compression and cracking induced by mechanical loading. The deformation process of bamboo scrimber dowel-bearing under sustained loading comprises four distinct stages, namely short-term deformation, initial creep, stable creep, and divergent creep. The divergent creep stage manifests exclusively at stress levels of S_L = 0.6, while at lower-stress levels, S_L = 0.2 and S_L = 0.4, only the first three stages are observed within the 51.5 h test duration. In addition, a preliminary analysis was conducted on the stiffness and strength reduction in bamboo scrimber dowel-bearing under sustained loading. These research findings elucidate the mechanical behavior of bamboo scrimber dowel-bearing under sustained loading, providing preliminary insights to inform future durability assessment and design methodology development for bamboo scrimber joint connections. Full article

The ongoing concern about advanced healthcare systems drives the development of highly functional medical textile products. However, despite rapid growth in fiber-based healthcare products, a comprehensive understanding of the relation between fiber and product properties remains limited. This review paper discusses the various fibers used in medical textiles, their classifications, applications, and properties. The existing pre-pandemic studies showed a narrow focus on classifications and applications. Therefore, in this review paper, very recent studies (post-pandemic) were analyzed, focusing on different physical, mechanical, biological, and chemical properties necessary for healthcare applications. The adoption of international standards for assessing these properties has enhanced the products’ global acceptance. Moreover, this paper explores recent innovations and challenges, indicating the future possibilities of medical textiles. The study summarizes a coalition between textiles and medical science to create a new field, Tex-Medical Engineering. Full article

This paper proposes a high-sensitivity and sensitivity-tunable vibration sensing system based on a switchable loop length optoelectronic oscillator (OEO). Carrier-sideband separation is realized by using an acousto-optic modulator (AOM), and the resonant cavity length is designed to be independent of the sensing fiber arm. Compared with a conventional 10 GHz OEO under the same total loop delay condition, the proposed architecture provides a theoretical sensitivity enhancement of approximately $1.93\times {10}^4$, without requiring a high RF oscillation frequency. Meanwhile, the system oscillates at only 80 MHz, which greatly reduces the implementation difficulty of the frequency detection circuit. The proposed scheme further introduces a mechanical optical switch (MOS) to select intra-loop fibers of different lengths, thereby reconfiguring the equivalent loop delay and the free spectral range of the OEO. Experimental results show that stable single-mode oscillation is achieved at 80.42 MHz with a side-mode suppression ratio of 51 dB. By selecting loop fiber lengths of 1200 m, 500 m and 0 m, frequency-to-displacement sensitivities of 0.892 GHz/cm, 1.93 GHz/cm and 9.27 GHz/cm are obtained respectively, with excellent linearity. A 600 Hz vibration signal is successfully demodulated with a signal-to-noise ratio of 72.1 dB. The proposed method provides a simple and reconfigurable solution for high-precision vibration measurement under different operating conditions. Full article

IEEE 1588Precision Time Protocol (PTP) synchronization accuracy is degraded by delay asymmetry in physical links. Accurate prediction and compensation of this asymmetry are essential for high-precision timekeeping. This paper presents a multi-horizon delay asymmetry prediction framework validated on a cesium-referenced testbed. The experimental platform integrates a cesium atomic clock (frequency stability $<5\times {10}^{-12}$), a Syncedge C10 PTP analyzer, and an RK3568 embedded TimeReceiver, providing hardware-timestamped ground-truth measurements over 24 h periods on both copper and fiber links under real operating conditions. A unified multi-output encoder architecture is compared against per-horizon recurrent models and classical baselines to predict delay asymmetry at five future horizons ($h\in \{1,2,4,8,16\}$, corresponding to $0.125$–$2.0$ s ahead). On copper links at an 8 s observation window, the unified model achieves a mean absolute error of 2.15 ns and an $R^2$ of 0.714 at the nearest horizon, statistically tied with the best per-horizon model (2.16 ns, $R^2=0.713$) while using 1.9–6.1× fewer total parameters (655K vs. 1.2–4.0M). On fiber links, all models achieve comparable accuracy with an MAE of 2.16–2.18 ns. The method requires ground-truth labels from a calibrated 1PPS or cesium reference; both training and inference require the same physical link and environmental conditions. Generalization to other settings remains untested. Full article

The increasing demand for sustainable, plant-based, gluten- and egg-free options is stimulating innovation in pasta products. The present work was aimed at investigating the effect of acorn flour (AF) at 50% (A50) and 100% (A100) in gluten-free and egg-free clean label tagliatelle, compared to a rice flour-based version (CTRL). A hydrogel consisting of carob seed flour and xanthan gum was used to reproduce the viscoelastic properties of gluten. Samples were analyzed for their rheological, physicochemical, nutritional, and sensory properties. The use of AF elevated the elastic modulus (G′), phenolic content, antioxidant activity, lipid content, and fiber content. The sample A100 was a “source of fiber”, according to EC Reg. 1924/06. In terms of cooking behavior, the incorporation of AF induced an increase in the water absorption index (WAI), the swelling index (SW), and a higher cooking loss. The addition of AF also resulted in a greater firmness at the cutting test and a brown color. The acorn tagliatelle had a fruity odor and flavor note. Based on these findings, AF could be a valid option in novel functional food prototypes, and also in gluten-free, egg-free and vegan versions. Full article

Lattice structures are widely utilized in lightweight engineering due to their design flexibility and tailorable mechanical properties. However, polymer lattices often exhibit limited load-bearing capacity and moderate crashworthiness under compression. This study proposes a hybrid reinforcement strategy based on the integration of carbon fiber-reinforced polymer (CFRP) rods into polymeric Kelvin-cell lattices. The specimens were manufactured via masked stereolithography, and the effects of rod placement pattern, the number of rods, and rod-length configuration were systematically investigated under quasi-static compression. Crashworthiness was evaluated in terms of force–displacement response, deformation mode, and crashworthiness metrics. Compared with the empty Kelvin-cell lattice, the best-performing hybrid configuration increased energy absorption, specific energy absorption, and mean crushing force by approximately 356%, 307%, and 356%, respectively. Mechanistically, distributed rod placement promoted more uniform load sharing, while the effect of increasing rod number depended strongly on the rod-length configuration. In addition, delayed or sequential reinforcement strategies provided superior performance and an enhanced balance between energy absorption and force efficiency. Regression models and ANOVA consistently identified rod-length configuration as the dominant design variable. These findings demonstrate that CFRP rod reinforcement can effectively enhance the crashworthiness of polymeric Kelvin-cell lattices, provided that the rod placement pattern, rod number, and rod-length configuration are designed jointly. Full article

Considered by some to be the largest metabolic organ of the body, the functional integrity of skeletal muscle is highly dependent on its exceptional plasticity, which is primarily governed by mitochondrial quality control. The signaling axis composed of AMP-activated protein kinase (AMPK), sirtuin 1 (SIRT1), and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) serves as a critical hub that senses cellular energy status, coordinates mitochondrial biogenesis, regulates muscle fiber type switching, and maintains protein homeostasis. This review systematically delineates the structural functions and synergistic regulatory network of the AMPK/SIRT1/PGC-1α signaling axis. It further elucidates the regulatory roles of this pathway under physiological conditions—such as exercise adaptation and muscle fiber-type transformation—and its dysregulated mechanisms in the pathogenesis of various skeletal muscle disorders, including sarcopenia, disuse atrophy, cachexia, neurogenic atrophy, muscular dystrophy, and type 2 diabetes mellitus-related myopathy. Building on this foundation, this review critically analyzes current multifaceted therapeutic strategies targeting this pathway, encompassing exercise and physical therapy, nutritional and natural products, and small molecule drugs, as well as gene and cell-based therapies. Finally, this review delves into the challenges facing clinical translation in this field, such as the complexity of the signaling network, individual variability, and bioavailability issues. It also proposes future research directions focused on developing precision intervention tools, establishing effective biomarker systems, and exploring combination intervention strategies. Collectively, the AMPK/SIRT1/PGC-1α signaling axis is central to maintaining skeletal muscle metabolic homeostasis, and targeting this pathway provides a robust theoretical foundation and broad application prospects for the prevention and treatment of skeletal muscle-related diseases. Full article

Background/Objectives: Patients undergoing surgery for metastatic spinal disease often require instrumented stabilization followed by radiotherapy and postoperative magnetic resonance imaging (MRI) surveillance. Titanium implants may generate artifacts that impair assessment of the operated level, whereas carbon fiber-reinforced polyetheretherketone (CFR-PEEK) constructs may improve MRI assessability. This study compared CFR-PEEK and titanium instrumentation with respect to postoperative MRI artifact burden, early outcomes, and oncological follow-up, and introduced a study-specific artifact grading system. Methods: This retrospective single-center cohort included 78 patients treated with instrumented stabilization for metastatic spinal disease: 33 with CFR-PEEK and 45 with titanium instrumentation. Postoperative MRI suitable for artifact assessment was available in 47 patients. Implant-related artifacts were evaluated using the Oncologic Spinal Instrumentation MRI Artifact Score (O-SIMAS), a 0–5 anatomy-based grading system. Early postoperative outcomes, local recurrence, progression-free survival, overall survival, and interrater agreement were analyzed. Results: CFR-PEEK instrumentation was associated with lower postoperative MRI artifact burden than titanium instrumentation, with median O-SIMAS scores of 2.0 versus 3.0, respectively (p < 0.001). High-grade artifacts were less frequent after CFR-PEEK than after titanium instrumentation (15.8% versus 67.9%; p = 0.0008). Titanium instrumentation remained independently associated with high-grade artifacts. Early postoperative outcomes, local recurrence, progression-free survival, and overall survival did not differ significantly between groups. O-SIMAS showed substantial pairwise interrater agreement. Conclusions: CFR-PEEK instrumentation was associated with improved postoperative MRI assessability and fewer diagnostically relevant artifacts than titanium instrumentation. No oncological benefit was shown. O-SIMAS may support structured artifact assessment, but requires external validation. Full article

High reclaimed asphalt pavement (RAP) mixtures can improve pavement sustainability by reducing virgin binder and aggregate demand, but high RAP contents may increase mixture stiffness and reduce cracking tolerance. This study evaluates whether commercially available para-aramid fibers can improve the intermediate-temperature cracking resistance of high-RAP hot-mix asphalt using the IDEAL-CT test. Two para-aramid fiber products, a wax-coated fiber and an emulsion-treated fiber, were evaluated at dosages of 0.05%, 0.10%, and 0.15% by total mixture weight in asphalt mixtures containing 15%, 25%, and 40% RAP. The results showed that fiber effectiveness depended strongly on RAP content, fiber treatment, and dosage. The 25% RAP mixture had the lowest control CTIndex and showed the greatest improvement from fiber addition. In this group, 0.10% wax-coated fiber increased CTIndex by 170%, while 0.15% emulsion-treated fiber increased CTIndex by 263%. For the 15% RAP mixture, 0.05% emulsion-treated fiber and 0.10% wax-coated fiber produced statistically significant improvements. For the 40% RAP mixture, 0.10% emulsion-treated fiber produced the highest mean CTIndex among all mixtures tested, but the improvement was not statistically significant because of high specimen variability. Overall, the findings indicate that para-aramid fibers can improve laboratory cracking resistance in RAP mixtures, but the optimum dosage is mixture-specific and should not be applied uniformly across RAP contents. Because this study was limited to Ideal-CT, additional rutting, fatigue, aging, workability analysis and field validation are recommended before broad implementation. Full article

Fiber Bragg grating (FBG)-based sensors are increasingly used for temperature and strain monitoring in both fission and fusion facilities, whereas their long-term mechanical reliability under intense γ–neutron fields remains insufficiently understood. Although radiation-resistant FBGs and optical fibers have demonstrated tolerance to fast-neutron fluences approaching 10²⁰ n/cm², the post-irradiation behavior of complete sensor assemblies, including their metallic packaging and joining regions, has received much less attention. This work presents methodology and results of assessing the post-irradiation mechanical properties of packaged FBG-based temperature and strain sensors. The investigated sensors were based on Cu-coated FBGs embedded in 316L stainless-steel bodies and joined using STEMET-1101 brazing filler metal. The sensors were irradiated in the cores of the IVG.1M and WWR-K research reactors to fast-neutron fluences of 4.5 × 10¹⁷ and 1.8 × 10²⁰ n/cm², with absorbed γ-doses of 29.1 MGy and 2.3 GGy, respectively. After decay storage and hot-cell disassembly, tensile testing, microhardness measurements, and SEM–EDS analysis were performed. The results demonstrate that the investigated metal-packaged FBG sensor of this design retained mechanical integrity under high-fluence reactor irradiation. Full article

Tenate cheese is a traditional Mexican pressed semi-hard cheese made from raw cow’s milk and wrapped in palm fiber. The characterization of this cheese remains scarce. This study presents an exploratory characterization of a single production batch of traditional Tenate cheese obtained from one artisanal producer, providing preliminary information on its physicochemical, microbiological, and proximate analyses, combined with consumer evaluation. The latter was analyzed using hierarchical cluster analysis (HCA) as an exploratory segmentation tool. Tenate cheese was characterized as a semi-hard cheese with active lactic fermentation, a lactic aroma, acidic and umami flavors, and a firm, granular texture. Microbiological analyses showed the absence of coliforms, enterobacteria, and Staphylococcus aureus among the microorganisms evaluated, whereas yeast counts exceeded the regulatory limit. As major foodborne pathogens were not included in the microbiological assessment, the overall microbiological safety of the product could not be confirmed. A total of 318 consumers from Aguascalientes (AGS, n = 149) and the Guadalajara Metropolitan Area (GMA, n = 169) evaluated the product using hedonic and Just-About-Right scales. Consumers from AGS reported significantly higher liking scores than those from GMA. Penalty analysis identified insufficient softness as the main attribute associated with lower liking in AGS, whereas low flavor intensity and weak aftertaste reduced acceptance in GMA. Hierarchical cluster analysis (HCA) identified three consumer segments in each location, revealing distinct preference patterns linked to regional expectations. The main contributions of this study are threefold. First, it contributes to the limited scientific knowledge available on Tenate cheese by providing a comprehensive characterization of the analyzed sample. Second, it shows that consumer acceptance differed between two regional markets, comparing two university-affiliated consumer groups, highlighting the value of consumer segmentation for product positioning. Third, it proposes and applies an integrated framework combining physicochemical, microbiological, nutritional, sensory, and consumer segmentation analyses that can be applied to the study of other artisanal cheeses. Full article

The Enterobacteriaceae family is a significant source of foodborne pathogens and represents a severe threat to human and animal health. These bacteria can penetrate the dairy supply chain through direct contact with cattle and the livestock environment and can survive production processes. Escherichia coli (E. coli), one of the most diffuse bacteria in raw and processed milk, exposes consumers to the risk of contaminated milk. As a result of this exposition, several milk-borne illness outbreaks have been reported worldwide, underscoring the urgent need for effective detection and prevention measures. Conventional analysis methods are effective but have significant limitations, including the requirement of pre-treatment and pre-enrichment steps. Thus, the need for advanced detection techniques that can accurately identify these pathogens without pre-treatment steps is critical. In this work, a proof-of-concept biosensor based on a spoon-shaped optical biochip was developed to detect E. coli via surface plasmon resonance (SPR) phenomena and was combined with a polyclonal antibody layer against E. coli as a molecular recognition element (MRE). The proposed label-free biosensing strategy, achieved by exploiting simple SPR spoon-shaped biochips, exhibits a remarkable detection limit (6.8 colony-forming units, CFU/mL) and high specificity towards other interfering bacteria belonging to the Enterobacteriaceae family. In addition, tests on commercial milk samples were carried out, achieving recovery values of 95% and 102% for whole milk and infant milk, respectively. The proposed spoon-shaped biosensor enables label-free biosensing without the need for microfluidic systems. It provides a rapid response (10 min), paving the way for its use as a point-of-care test (POCT) in real-world settings. Full article

This study compared the effects of air freezing (AF), immersion freezing (IF), and ultrasound-assisted immersion freezing (UIF) at different power levels on the physicochemical properties, oxidative characteristics, and the structural and functional properties of myofibrillar protein (MP) of fresh beef. The results showed that UIF treatments generally outperformed AF and IF, with UIF-400 W exhibiting the best performance in maintaining beef quality. Specifically, UIF-400 W mitigated muscle fiber damage by inhibiting ice crystal growth, significantly improved water-holding capacity and color stability, reduced shear force, and effectively delayed protein and lipid oxidation. In addition, UIF-400 W brought the rheological properties, emulsifying properties, water distribution, and gel microstructure of MP closer to those of fresh beef. These findings highlight that UIF-400 W can effectively preserve beef quality as well as the structural and functional characteristics of MP, reduce oxidative damage, and thus become a promising technology for quality improvement of beef during freezing. Full article

This study investigates the thermo-mechanical and microstructural performance of concrete incorporating waste tire rubber (WR) and recycled steel fibers (WS) under elevated temperatures. Four mixtures were prepared: plain concrete (PL), rubber-modified concrete (WR5), and hybrid mixtures containing 0.4% and 0.8% steel fibers (WS0.4WR5 and WS0.8WR5). Specimens were exposed to temperatures of 400 °C, 600 °C, and 800 °C to simulate fire conditions. The results indicate that the incorporation of rubber reduces compressive strength at ambient temperature due to its lower stiffness and weak interfacial bonding. However, the addition of recycled steel fibers significantly improves crack resistance and enhances thermal stability. At 400 °C, the WS0.8WR5 mixture showed a retention rate of 92.9% (absolute strength: 44.32 MPa), compared to 72.2% for plain concrete (absolute strength: 44.11 MPa). Although the hybrid mixture has a lower ambient strength (47.68 MPa vs. 61.07 MPa), its superior retention makes it competitive in fire scenarios. Ultrasonic pulse velocity (UPV) measurements revealed a strong correlation with compressive strength degradation, confirming its effectiveness as a non-destructive indicator of internal damage. Microstructural analyses (SEM, XRD, and TGA-DTA) demonstrated that elevated temperatures lead to dehydration, phase transformation, and increased porosity, while steel fibers help maintain matrix integrity through crack-bridging mechanisms. The findings highlight a synergistic interaction between waste rubber and steel fibers, offering a sustainable and effective approach for improving the fire resistance of concrete. Full article

Background: Whether congenital cataract-related visual deprivation and subsequent rehabilitation are associated with retinal structural and vascular network differences remains unclear. This study evaluated superficial retinal vascular network descriptors and retinal nerve fiber layer (RNFL) thickness in children after bilateral congenital cataract extraction and secondary intraocular lens implantation. Methods: Age-matched children served as controls. Participants underwent spectral-domain optical coherence tomography (OCT) and 6 × 6 mm optical coherence tomography angiography (OCTA). Metrics were magnification-corrected, and comparisons used generalized estimating equation models adjusted for age, eye side, axial length, and spherical equivalent. Results: Eighteen pseudophakic children (36 eyes; median age, 8 years) and 17 controls (34 eyes; median age, 9 years) were included. In adjusted models, macular mean vessel diameter was higher in pseudophakic eyes (β = 11.16 µm; p = 0.003), as was macular mean tortuosity (β = 0.032; p = 0.001). Branchpoint density was lower in direction but not independently significant (p = 0.125). Choroidal thickness, choroidal vascularity index, and foveal avascular zone area did not differ significantly. Temporal RNFL thickness was greater in pseudophakic eyes (β = 13.37 µm; p = 0.007); other RNFL parameters were not significant. Conclusions: These findings suggest exploratory differences in superficial vascular network morphology and temporal RNFL thickness. However, because the groups differed clinically in best-corrected visual acuity, refractive status, and axial length, residual confounding cannot be excluded despite magnification correction and adjusted modeling. Full article