Search Results (284)

This study investigates the production and characterization of basalt continuous fibers (BCFs) with varying oxide contents (including Na₂O, SiO₂, CaO, TiO₂, and Al₂O₃), derived from modified basalt bulk glasses. The fibers were created through a two-stage process that included the preparation of basalt glasses followed by fiber drawing. A key focus of the research was on evaluating the mechanical properties of BCF after low-temperature treatments. Tensile testing revealed that the maximum tensile strength of the fibers was 1915 MPa at room temperature, which decreased to 1714 MPa at −196 °C, representing a shift of −10.5%. The addition of sodium oxide not only broadened the fiber-forming temperature range but also increased the strength to 2351 MPa. However, significant reductions in strength were observed at cryogenic temperatures, particularly for the Na-rich sample, which experienced a decrease of 32.8%. These findings highlight the importance of optimizing oxide content and minimizing hydroxyl (OH) groups to enhance the performance of basalt fibers in low-temperature applications, positioning them as viable materials for use in extreme environments. Full article

Rammed earth (RE), a traditional material aligned with circular economy (CE) principles, has been gaining renewed interest in contemporary construction due to its low environmental impact and compatibility with sustainable building strategies. Though not a modern invention, it is being reintroduced in response to the increasingly strict European Union (EU) regulations on carbon footprint, life cycle performance, and thermal efficiency. RE walls offer multiple benefits, including humidity regulation, thermal mass, plasticity, and structural strength. This study also draws attention to their often-overlooked ability to mitigate indoor overheating. To preserve these advantages while enhancing thermal performance, this study explores insulation strategies that maintain the vapor-permeable nature of RE walls. A parametric analysis using Delphin 6.1 software was conducted to simulate heat and moisture transfer in two main configurations: (a) a ventilated system insulated with mineral wool (MW), wood wool (WW), hemp shives (HS), and cellulose fiber (CF), protected by a jute mat wind barrier and finished with wooden cladding; (b) a closed system using MW and WW panels finished with lime plaster. In both cases, clay plaster was applied on the interior side. The results reveal distinct hygrothermal behavior among the insulation types and confirm the potential of natural, low-processed materials to support thermal comfort, moisture buffering, and the alignment with CE objectives in energy-efficient construction. Full article

Famed lawyer Clarence Darrow (1857–1938) argued strongly for an early-life public health approach to crime prevention, one that focused on education, poverty reduction, and equity of resources. Due to his defense of marginalized persons and his positions that were often at odds with his legal colleagues and public opinion, he was known as the Big Minority Man. He argued that the assumption of free will—humans as free moral agents—justifies systems of inequity, retributive punishment, and “unadulterated brutality.” Here, the authors revisit Darrow’s views and expand upon them via contemporary research. We examine increasingly louder argumentation—from scholars across multiple disciplines—contending that prescientific notions of willpower, free will, blameworthiness, and moral responsibility, are contributing to social harms. We draw from biopsychosocial perspectives and recent scientific consensus papers calling for the dismantling of folk psychology ideas of willpower and blameworthiness in obesity. We scrutinize how the status quo of the legal system is justified and argue that outdated notions of ‘moral fiber’ need to be addressed at the root. The authors examine recent arguments for one of Darrow’s ideas—a public health quarantine model of public safety and carceral care that considers the ‘causes of the causes’ and risk assessments through a public health lens. In our view, public health needs to vigorously scrutinize the prescientific “normative” underpinnings of the criminal justice system. Full article

The growing global prevalence of non-communicable diseases (NCDs) is drawing an increasing amount of attention to the health-promoting potential of whole-grain dietary fibers. Whole grains are rich sources of both soluble dietary fiber (SDF) and insoluble dietary fiber (IDF), contributing distinct physicochemical properties and playing vital roles in promoting human health. This review provides a comprehensive analysis of the dietary fiber compositions of various whole grains, including wheat, oats, barley, rye, corn, sorghum, and rice, highlighting their structural characteristics, physiochemical properties, and associated health benefits. The physicochemical properties of dietary fibers, such as solubility, water- and oil-holding capacity, viscosity, swelling ability, and bile-acid-binding capacity, contribute significantly to their technological applications and potential health benefits, particularly in the prevention of NCDs. Although there is growing evidence supporting their health benefits, global whole-grain intake remains below recommended levels. Therefore, promoting whole-grain intake and developing fiber-rich functional foods are essential for enhancing public health and preventing chronic diseases. Future research should focus on enhancing the bioavailability and functionality of whole-grain dietary fibers, optimizing the methods by which they are extracted, and exploring their potential applications in the food and pharmaceutical industries. Full article

Bio-nanocomposites based on poly (vinyl alcohol) (PVA) and cellulosic nanostructures are favorable for active food packaging applications. The current study systematically investigates the mechanical properties, gas permeation, and swelling parameters of PVA composites with cellulose nanocrystals (CNC) or nano lignocellulose (NLC) fibers. Alterations in these macroscopic properties, which are critical for food packaging applications, are correlated with structural information at the molecular level. Strong interactions between the fillers and polymer host matrix were observed, while the PVA crystallinity exhibited a maximum at ~1% loading. Finally, the orientation of the PVA nanocrystals in the uniaxially stretched samples was found to depend non-monotonically on the CNC loading and draw ratio. Concerning the macroscopic properties of the composites, the swelling properties were reduced for the D1 food simulant, while for water, a considerable decrease was observed only when high NLC loadings were involved. Furthermore, although the water vapor transmission rates are roughly similar for all samples, the CO₂, N₂, and O₂ gas permeabilities are low, exhibiting further decrease in the 1% and 1–5% loading for CNC and NLC composites, respectively. The mechanical properties were considerably altered as a consequence of the good dispersion of the filler, increased crystallinity of the polymer matrix, and morphology of the filler. Thus, up to ~50%/~170% enhancement of the Young’s modulus and up to ~20%/~50% enhancement of the tensile strength are observed for the CNC/NLC composites. Interestingly, the elongation at break is also increased by ~20% for CNC composites, while it is reduced by ~40% for the NLC composites, signifying the favorable/unfavorable interactions of cellulose/lignin with the matrix. Full article

Noncorrosive concrete reinforcement, such as polymer fibers, is needed to overcome the current issues caused by corroded steel reinforcements. Fibers made of polypropylene show a low bonding behavior in concrete. Fillers can help to overcome this issue but often lead to reduced mechanical properties. Core-shell fibers, which split the mechanical properties and the bonding behavior between the core and the shell component, could be a solution. This study investigates mono-material and core-shell fibers produced with calcium carbonate and bentonite fillers and compares their behavior in tensile tests, density measurements, contact angle measurements, topography measurements, single fiber pull-out tests, reflected light microscopy, and thermogravimetric analysis. The fillers caused an increased drawability, resulting in higher mechanical properties. Further, in the core-shell fibers, the calcium carbonate increased the surface roughness, which led to a better anchoring of the fiber in concrete, which was also visible in the deformation during pull-out observed in reflected light microscopy pictures. The thermogravimetric analysis showed a delay in onset of degradation for fibers containing bentonite. Full article

Chondrocytes maintain cartilage integrity through coordinated regulation of extracellular matrix (ECM) synthesis and remodeling. These processes depend on ECM dynamic interactions, mediated by integrin-based focal adhesions and associated cytoskeletal components. While the roles of core adhesion proteins are well described, the involvement of sarcoglycans (SGs) remains unclear in chondrocytes. Drawing parallels from striated muscle, where the SG subcomplex stabilizes the sarcolemma, we hypothesized that SGs similarly integrate into chondrocyte adhesion complexes. This study investigated the SGs (α, β, γ, δ) expression with cytoskeletal and adhesion proteins, including actin and vinculin, in human chondrocytes cultured by immunofluorescence, qPCR, and siRNA-mediated silencing. All four SG isoforms were expressed in the cytoplasmic and membrane domains, with enrichment at focal adhesion sites. Double labeling revealed SG colocalization with F-actin stress fibers and vinculin, indicating integration into the core adhesion complex. Silencing of each SG resulted in disrupted actin stress fibers, diffuse vinculin distribution, reduced focal plaque number, and a change in cell morphology. These findings support the hypothesis that SGs regulate actin cytoskeletal dynamics and focal contact stabilization. Loss of SG function compromises chondrocyte shape and adhesion, highlighting the importance of these glycoproteins also in non-muscle cells. Full article

Carbon-fiber-reinforced polymer (CFRP) preforms are vital for high-performance composite structures, yet the real-time detection of surface yarn alignment defects is hindered by complex textures. This study introduces a novel machine vision framework to enable the precise, real-time identification of such defects in CFRP preforms. We proposed obtaining the frequency spectrum by removing the zero-frequency component from the projection curve of images of carbon fiber fabric, aiding in the identification of the cycle number for warp and weft yarns. A texture structure recognition method based on the artistic conception drawing (ACD) revert is applied to distinguishing the complex and diverse surface texture of the woven carbon fabric prepreg from potential surface defects. Based on the linear discriminant analysis for defect area threshold extraction, a defect boundary tracking algorithm rule was developed to achieve defect localization. Using over 1500 images captured from actual production lines to validate and compare the performance, the proposed method significantly outperforms the other inspection approaches, achieving a 97.02% recognition rate with a 0.38 s per image processing time. This research contributes new scientific insights into the correlation between yarn alignment anomalies and a machine-vision-based texture analysis in CFRP preforms, potentially advancing our fundamental understanding of the defect mechanisms in composite materials and enabling data-driven quality control in advanced manufacturing. Full article

Fiber-reinforced polymer (FRP) pipes have emerged as a preferred alternative to conventional metallic piping systems in various industries, including chemical processing, marine, and oil and gas industries, owing to their superior corrosion resistance, high strength-to-weight ratio, and extended service life. However, ensuring the long-term reliability and structural integrity of FRP pipes presents significant challenges, primarily because of their anisotropic and heterogeneous nature, which complicates defect detection and characterization. Traditional non-destructive testing (NDT) methods, which are widely applied, often fail to address these complexities, necessitating the adoption of advanced digital techniques. This review systematically examines recent advancements in digital NDT approaches with a particular focus on their application to composite materials. Drawing from 140 peer-reviewed articles published between 2016 and 2024, this review highlights the role of numerical modeling, simulation, machine learning (ML), and deep learning (DL) in enhancing defect detection sensitivity, automating data interpretation, and supporting predictive maintenance strategies. Numerical techniques, such as the finite element method (FEM) and Monte Carlo simulations, have been shown to improve inspection reliability through virtual defect modeling and parameter optimization. Meanwhile, ML and DL algorithms demonstrate transformative capabilities in automating defect classification, segmentation, and severity assessment, significantly reducing the inspection time and human dependency. Despite these promising developments, this review identifies a critical gap in the field: the limited translation of advanced digital methods into field-deployable solutions specifically tailored for FRP piping systems. The unique structural complexities and operational demands of FRP pipes require dedicated research for the development of validated digital models, application-specific datasets, and industry-aligned evaluation protocols. This review provides strategic insights and future research directions aimed at bridging the gap and promoting the integration of digital NDT technologies into real-world FRP pipe inspection and lifecycle management frameworks. Full article

This study innovatively presents a hollow-core anti-resonant fiber integrating double-tube nesting and a single-layer anti-resonant wall. Featuring an exclusive two-layer cladding configuration along with an outer cladding circular ring, it differs significantly from traditional fibers. After careful parameter optimization, at 1.55 μm wavelength, the fiber shows excellent performance. Its confinement loss drops to 0.00088 dB/km, 1–2 orders lower than traditional ones. The proportion between the loss of the lowest higher-order mode and that of the fundamental mode reaches 19,900, indicating excellent single-mode performance. In the case of a bending radius of 11–14.2 cm, the x-polarization loss is below 0.001 dB/km, showing good bending resistance. Through structural comparisons, this paper quantitatively reveals the effects of the anti-resonant wall, cladding tube, and outer cladding ring on fiber performance. From the practical fiber-drawing process, it thoroughly analyzes the impact of the outer connecting tube’s offset angle on fiber performance. This research provides crucial theoretical support for new hollow-core fiber design, manufacture, and application, and is expected to drive technological innovation in this field. Full article

The temperature of the tools and the moisture content of the material play a significant role in the 3D forming of paperboard in terms of the degree of forming and the quality of the formed part. It is known that different forming mechanisms act within the paperboard in different areas of the deep drawing tools during the deep drawing of paperboard and that the success of the forming process is also based on a dynamic interaction between material moisture and tool surface temperature. However, it has not yet been investigated how the forming parameters can be influenced by an individually adjustable temperature for the individual tool areas and how they influence the complex interaction with the moisture content of the paperboard during the forming process. Due to the inhomogeneity of the natural fiber network of paperboard, rapid and directed temperature changes of the tools are also of interest in order to be able to react quickly to variations of material properties in order to prevent frequent process failure within a continuous production. In this paper, test tools with individually controllable heating zones were developed and the use of different heating technologies to improve the rate of temperature change was analyzed. These tools were used to investigate the influence of temperature in the individual sections of the deep drawing process and how the moisture content can be specifically controlled during the process. It was found that with modern heating technology, the deep-drawing tools can be tempered significantly faster and that a temperature difference between the blank holder zone and the drawing cavity zone has a positive influence on the formability and the fixation of the shape of the part produced. This effect was further enhanced by the fact that, thanks to the temperature tailored tool, it was possible to work with a very high moisture content of the paperboard. Full article

As a bio-based polymer, polybutylene succinate (PBS) has extensive applications in plastic products and film manufacturing. However, its low melt strength results in poor spinnability, and during the forming process, it tends to form large-sized spherulites and exhibit filament adhesion phenomena. These limitations have hindered its development in the field of fiber spinning. To enhance fiber strength, this work systematically investigated the effects of spinning temperature and spinning speed on the properties and structure of PBS pre-oriented yarns (PBS-POY). The results indicated that appropriately lowering the spinning temperature and increasing the spinning speed could improve the mechanical properties of the fibers. When the spinning temperature was 195 °C and the spinning speed reached 2500 m/min, the tensile strength of pre-oriented yarns achieved 2.09 cN/dtex. Furthermore, the evolution of properties and structures of pre-oriented yarns under maximum drawing conditions across different spinning speed systems was examined. By synchronously analyzing the correlations among mechanical properties, thermal behavior and condensed state structures, the structural performance regulation mechanism under the synergistic effect of spinning–drawing processes was revealed. The results demonstrated that fibers produced at higher spinning speeds contained more numerous and smaller spherulites. After maximum drawing, these smaller spherulites split into lamellae with higher uniformity, resulting in final fibers with smaller crystal sizes, higher crystallinity and improved orientation. As the spinning speed increased, the average crystal size of the final fibers decreased; the long period of the final fibers extended from 8.55 nm to 9.99 nm, and the mechanical strength improved to 2.72 cN/dtex. Full article

In this work, we investigated the influence of stabilization on polylactic acid (PLA) fibers. Biodegradable plastics have a significantly lower environmental impact because they are produced from renewable resources and can break down through the action of microorganisms. Considering the issues of polymer waste production and accumulation, PLA, being a biodegradable material derived from renewable sources, represents a promising solution for the future. Nowadays, several studies on PLA evaluate its properties for various applications. However, we focused on improving the user properties of PLA fibers. Different thermal stabilization processes simulate the use of PLA fibers and their impact on the behavior and properties of PLA fibers exposed to these conditions. The thermal behavior of PLA fibers (the melting temperatures, the crystallization temperatures, and enthalpies), mechanical (tenacity and elongation at the break, Young’s modulus), and thermomechanical (the shrinkage and the temperature of first distortion) properties of PLA fibers have been investigated in detail. Our research results show that the PLA fibers can achieve better properties (as mechanical and dimensional) by stabilization. It is about the dimensional stability of the fibers for applications such as knitting and weaving. Under the monitored stabilization conditions, shrinkage was reduced (especially at higher stabilized temperatures above 85 °C), which can improve the next process of textile processing (knitting and weaving). Thermal stabilization after drawing is one possibility. The stabilization conditions will depend on the potential use of the PLA fibers. Full article

This paper reviews the research progress of bionic soft robot technology learned from octopuses. The number of related research papers increased from 760 in 2021 to 1170 in 2024 (Google Scholar query), with a growth rate of 53.95% in the past five years. These studies mainly explore how humans can learn from the physiological characteristics of octopuses for sensor design, actuator development, processor architecture optimization, and intelligent optimization algorithms. The tentacle structure and nervous system of octopus have high flexibility and distributed control capabilities, which is an important reference for the design of soft robots. In terms of sensor technology, flexible strain sensors and suction cup sensors inspired by octopuses achieve accurate environmental perception and interaction. Actuator design uses octopus muscle fibers and movement patterns to develop various driving methods, including pneumatic, hydraulic and electric systems, which greatly improves the robot’s motion performance. In addition, the distributed nervous system of octopuses inspires multi-processor architecture and intelligent optimization algorithms. This paper also introduces the concept of expected functional safety for the first time to explore the safe design of soft robots in failure or unknown situations. Currently, there are more and more bionic soft robot technologies that draw on octopuses, and their application areas are constantly expanding. In the future, with further research on the physiological characteristics of octopuses and the integration of artificial intelligence and materials science, octopus soft robots are expected to show greater potential in adapting to complex environments, human–computer interaction, and medical applications. Full article

The increase in composite material waste from the aviation and wind energy sectors will become a significant environmental challenge in the near future. This escalation is attributed to the enhanced use of new, advanced composite materials, such as Glass Fiber Reinforced Polymer (GFRP). Despite their benefits, the disposal of these materials at their end-of-life poses considerable environmental and logistical challenges. Assessing the condition of these materials is thus pivotal to develop sustainable strategies for their recycling, reusing, or repurposing. This study investigates the use of Non-Destructive Testing (NDT) techniques, with a focus on Active Thermography, to evaluate GFRP components’ suitability for sustainable management without compromising the material integrity. This research highlights the use of Active Thermography for extensive, non-invasive inspections, due to its capability to inspect a large area quickly using external energy heating. It delves into Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT), two advanced signal post-processing techniques, tested on GFRP materials with purposefully induced defects. Finally, an automated method based on the Signal-to-Noise Ratio (SNR) value is implemented for defect detection, with which defects of a 5 mm diameter and a 3 mm depth can be detected. The document elaborates on the theoretical principle of NDT, PPT, and PCT, details the experimental methodology and specimens, and analyzes the outcomes of employing these techniques, drawing comparisons between them. Full article