Steel Fiber Reinforced Self-Compacting Concrete (SFSCC) is an innovative material that integrates the self-compacting ability of SCC with the strength and durability benefits of steel fibers. This review examines the mix design, fresh and hardened properties, durability, and microstructural characteristics of SFSCC, highlighting its performance advantages and challenges. Fresh properties were assessed using slump flow, T500, L-box, V-funnel, J-ring, and U-box tests, ensuring compliance with self-compacting standards. Hardened properties were evaluated through compressive strength, split tensile strength, flexural strength, elastic modulus, bond strength, flexural toughness, and impact resistance tests. Durability was examined using ultrasonic pulse velocity (UPV), permeability, sorptivity, and sulfate resistance tests, while microstructural analysis was conducted using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Energy Dispersive Spectroscopy (EDS). Findings reveal that incorporating steel fibers enhances strength, ductility, and durability. Compressive strength increased by 10%–35%, tensile strength by 11%–113%, and flexural strength by 10%–80%, while impact resistance improved significantly, with crack impact energy increasing by up to 3433%. Durability tests indicated improved resistance to water penetration and sulfate exposure, with a 6%–59% reduction in permeability and minimal compressive strength loss of 8.6% after prolonged sulfate exposure. Microstructural analysis confirmed reduced porosity and stronger interfacial bonding, contributing to long-term performance. Despite these advantages, challenges remain in optimizing mix design, ensuring uniform fiber dispersion, and addressing long-term durability. Further research is needed to refine material composition and enhance the sustainability and structural efficiency of SFSCC in construction applications.

On the physical meaning of the fiber segment length in fiber strength models

Recovery of glass fiber from retired wind turbine blades based on low-temperature plasma assisted flotation.

Enhancing cotton fiber quality is essential for improving textile production. The transition from fiber elongation to secondary cell wall (SCW) synthesis is a critical developmental phase that determines both fiber length and strength. Although MYB transcription factors regulate the process, their precise functions remain incompletely characterized. In this study, we employed genome-wide identification and expression screening, together with candidate gene association analysis, to identify GhMYS1. This gene, selected from 186 cotton 1R-MYB transcription factors, is specifically expressed during the fiber elongation stage (5-15 days post-anthesis (DPA)). CRISPR/Cas9-mediated knockout of GhMYS1 significantly reduced fiber length, increased cell wall thickness, and raised the micronaire value compared to the control. Concurrently, expression of SCW synthesis-related genes GhCESA4, GhCESA8, and GhCOBRA4D was markedly up-regulated, accompanied by a pronounced increase in cellulose content. Yeast one-hybrid (Y1H), electrophoretic mobility shift (EMSA), and luciferase (LUC) assays demonstrated that GhHOX3 binds to the L1-box motif in the GhMYS1 promoter and activates its transcription in fibers and trichomes. The nuclear-localized GhMYS1 protein contains a C-terminal EAR motif with transcriptional repression activity. Through its N-terminal MYB domain, GhMYS1 binds directly to the promoters of GhCESA4 and GhCESA8, repressing their transcription and thereby delaying the onset of SCW deposition to facilitate fiber elongation. We propose a GhHOX3-GhMYS1-GhCESA4/8 regulatory module that governs the transition from fiber elongation to SCW synthesis. This study provides valuable genetic resources for molecular design breeding of cotton fiber quality and offers insights into the function of 1R-MYB transcription factors in fiber development.

Self-winding assembly of bamboo fibers via targeted delignification for superior mechanical and antibacterial performance.

To identify risk factors for postpartum pelvic floor dysfunction (PFD) diagnosed at 6 weeks after delivery in a Chinese population. This retrospective study examined data from 828 postpartum women in China, collected from January 2020 to August 2021. Multivariate analyses were employed to identify factors associated with six outcomes of PFD, including anterior vaginal wall prolapse, posterior vaginal wall prolapse, uterine prolapse, stress urinary incontinence (SUI), and impaired type I and type II muscle fiber strength. A series of factors are considered to be associated with PFD. Cesarean delivery significantly reduced severe anterior vaginal wall prolapse risk (OR=0.426, P＜0.001). Age, overweight (BMI ≥24.9 kg/m²), macrosomia (birth weight ≥4000g), forceps-assisted delivery, and constipation significantly increased risks of anterior and posterior vaginal wall prolapse, uterine prolapse, and SUI (all OR>1, P<0.05). Twin pregnancy reduced type I (OR=0.430, P=0.013) and type II (OR=0.385, P=0.009) muscle fiber strength but increased risks of anterior vaginal wall prolapse, uterine prolapse, and SUI. Higher parity (two or more) was correlated with higher risks of anterior (OR=2.402, P<0.001) and posterior vaginal wall prolapse (OR=2.977, P=0.0003) and SUI (OR=1.726, P=0.001). Heavy physical labor was strongly associated with posterior vaginal wall prolapse (OR=6.285, P=0.008), uterine prolapse (OR=5.264, P=0.009), and SUI (OR=3.987, P=0.024). Underweight status (BMI<18.5 kg/m²) significantly increased risks of impaired type I (OR=0.173, P<0.001) and type II muscle fiber strength (OR=0.197, P=0.0003). This study identified significant PFD risk factors in a Chinese population, highlighting the importance of targeted prenatal, perinatal, and postpartum care to mitigate these risks. In addition to uncontrollable factors like mode of delivery, age, and parity, interventions targeting weight gain and fetal macrosomia during pregnancy and appropriate assisted delivery could mitigate the risks of PFD. Educational programs for pregnant women should emphasize a proper diet and lifestyle. For women with chronic constipation, clinical treatment should be carried out as soon as possible to avoid further aggravating the damage to the pelvic floor muscles.

A two-step recycling method for upgraded glass fiber from wind turbine blades and its failure mechanisms.

The tensile strength of unidirectional fiber-reinforced composites is influenced by stochastic fiber breakage and load redistribution. Existing strength models have limitations in predicting fiber break density, clustering, and failure. This study introduces a framework that combines full-field computations based on the fast Fourier transform with a discrete fiber-damage model, yielding a voxelized 3D microstructure in which fibers are grouped into breakage-susceptible blocks according to a Weibull distribution. A stress-based monotonic loading is applied, declaring macroscopic failure when no converged damaged state is achieved. This approach reduces reliance on assumptions regarding load transfer and matrix contributions, facilitating large-scale simulations. It allows for variations in fiber strength distributions and matrix behaviors, independent of initial modeling assumptions. The framework is tested within a community benchmark for consistency with experimental results. After calibrating numerical parameters, it is compared with other models and experiments, showing improved stress–strain predictions, particularly in strength and modulus softening. However, fiber break density remains overestimated, as in existing models. Sensitivity analyses reveal limited influence from fiber debonding length and failure criteria. An alternative set of Weibull parameters aligns stress–strain curves and fiber break density, but may not be valid for single-fiber tests, suggesting caution in extrapolating Weibull laws.

Recent advancements in concrete technology have led to the use of fiber reinforcement. The main purpose of fiber reinforcement is fracture control, not structural reinforcement. By properly combining two or more fiber types, hybrid fiber reinforced concrete has the ability to enhance concrete's overall qualities and produce performance concrete. The purpose of this study is to investigate the compressive and flexural strength of hybrid fiber reinforced concrete, which uses fibers made of polypropylene and Glass. Five M25 grade mixes, one standard control mix, and four hybrid fiber reinforced concrete mixes were made specifically for this purpose. To ascertain the workability of the hybrid fiber reinforced concrete. a compressive and flexural test is conducted to investigate the hybrid fiber reinforced concrete's mechanical characteristics.

Cotton (Gossypium hirsutum L.) breeding has primarily emphasized fiber yield and quality, yet plant architectural, developmental, and seed morphological traits also play key roles in productivity and management. Here, we dissect the genetic basis of four such traits: plant height (HT), number of nodes with one branch (N1B), days to flowering (DTF), and average surface area per seed (ASAS) using exotic × elite Upland cotton populations. Both population-specific and joint analyses of the populations identified 17 QTLs collectively, with ASAS having the largest number of detected QTLs. The exotic line T326 showed the highest potential for the improvement of ASAS. While HT, N1B, and DTF displayed limited genetic variance in these populations, gene ontology enrichment highlighted the CCR4-NOT complex as a potential shared regulatory hub connecting ASAS and DTF. In addition, ASAS showed a highly significant positive correlation and overlapping QTL regions with fiber strength and upper half mean length described in a companion paper, suggesting the possibility of strong linkage or pleiotropic effects of these genomic regions, which could be beneficial commercially. Overall, the data suggested no prevalence of negative allelic trade-offs or linkage drag from these secondary traits for the improvement of fiber quality traits, underscoring the value of exotic germplasm for simultaneous enhancement of fiber quality and seed morphology in Upland cotton breeding.

The clarification of the fracture behavior of CFRP under multiaxial loading has become a research focus; therefore, understanding of the properties of carbon fiber is essential. This study experimentally and analytically clarifies the effect of torsional loading on the tensile strength of PAN-based carbon fiber. Combined tensile-torsional tests were performed under proportional-loading. The results showed that tensile strength decreased as torsional stress increased. Weibull analysis, treating principal stress as a stochastic variable, confirmed that strength variation decreases as the torsional-to-tensile stress ratio increases. To investigate the cause, a defect size distribution analysis was conducted. The findings indicated that the critical defect size increases as the principal stress plane angle increases, whereas its variation decreases. Considering the anisotropy of fiber strength, a new concept of normalized principal stress was introduced. This revealed that fracture behavior conforms to the maximum principal stress theory. Accordingly, a new fracture criterion was formulated using uniaxial tensile strength, X and pure torsional strength, S as: σ = X 1 − τ / S 2 .

MicroRNA (miRNA), as a molecule with regulatory functions, has become a research hotspot for diagnosis or prognosis in various diseases. This study investigates the predictive value of miR-205-5p concerning abdominal adhesions and postpartum complications in women undergoing secondary cesarean sections with a scarred uterus. Before the second cesarean section, the condition of the scar was evaluated using the Patient and Observer Scar Assessment Scale (POSAS). The serum levels of miR-205-5p were quantified through RT-qPCR, and the pregnant women were divided into the high-expression group and the low-expression group based on the average level of miR-205-5p. Subsequent analyses compared the abdominal scar scores, pelvic floor muscle fiber strength, incidence of abdominal adhesions, and the rate of postpartum complications. The predictive value of miR-205-5p for abdominal adhesions and complications was assessed via receiver operating characteristic (ROC) curve. The findings revealed a negative correlation between miR-205-5p levels and POSAS scores. Furthermore, the incidence of abdominal adhesions and postpartum complications was significantly lower in the high-expression group compared to their low-expression counterparts. The area under the curve (AUC) for predicting abdominal adhesions and postpartum complications using miR-205-5p was determined to be 0.822 and 0.831, respectively. Notably, no significant differences were observed in pelvic floor muscle function between the two groups. In conclusion, this study posits that miR-205-5p holds substantial promise as a predictive biomarker for abdominal adhesions and postpartum complications in women with a scarred uterus.

Directed cell migration is essential for numerous physiological processes, yet the combined effects of various biomechanical mechanisms remain underexplored. In this study, we conducted experiments on mast cell migration and developed a stochastic model based on experimental results to investigate cell migration and the durotaxis mechanism. Our model incorporates both biomechanical and biochemical mechanisms, with an emphasis on polymerization range and mechanical stimuli. Our model, validated by experimental data, simulates cell migration in uniform and stiffness-gradient environments. The model highlights the importance of considering both the strength of focal adhesion (FA) and stress fiber (SF) contractility to replicate the durotaxis phenomenon and distinguishes the different mechanical mechanisms that dominate cell migration in various physical environments. Additionally, we derived one-dimensional theoretical results for our framework, which align well with existing continuum models and experiments. In conclusion, the proposed model offers a straightforward method to simulate cell migration under various mechanical stimuli and provides valuable insights into cellular mechano-sensing systems.

The simultaneous improvement of fiber strength (FS) and lint percentage (LP) is a critical objective for achieving high-quality and high-yield cotton production. Identifying key genes and their regulatory networks that govern the synergistic development of FS and LP is essential for achieving their simultaneous improvement. In our previous study, a stable chromosome segment, Seg-D06-2, was identified for its ability to concurrently enhance both FS and LP with high reliability. In the present study, homozygous individuals harboring the Seg-D06-2 segment within a nearly uniform genetic background were selected to construct a large BC6F2 chromosome segment substitution line (CSSL) population comprising 3324 individuals. Extreme individuals characterized by simultaneous improvement in FS and LP, which shared similar genetic and phenotypic backgrounds, were subjected to comparative transcriptomic and weighted gene co-expression network analysis (WGCNA) at 0, 5, 10, 15, 20, and 25 days post-anthesis (DPA). The results highlighted the ’blue’ and ’yellow’ modules as being significantly associated with the simultaneous improvement of FS and LP. Four hub genes (GH_D06G0542, GH_D06G1609, GH_D06G0627 and GH_D06G2689) and two DEGs (GH_D06G0564 and GH_D06G0723) were identified in the ’blue’ module. Three hub genes (GH_D06G0540, GH_D06G0558 and GH_D06G0636) and one DEG (GH_D06G0527) were identified in the ’yellow’ module. These 10 key genes likely play pivotal roles in regulating the synergistic development of FS and LP, warranting further investigation. The reliability of the RNA-seq data was confirmed by qRT-PCR. This study provides a valuable resource for molecular breeding aimed at the simultaneous improvement of FS and LP and offers new insights into the molecular mechanisms governing their synergistic development.

Polylactic acid (PLA), a biodegradable polymer derived from renewable resources, represents a promising candidate for sustainable textiles. Nevertheless, its practical application remains limited by the requirement for high-temperature dyeing, which can induce polymer hydrolysis and lead to the loss of fiber strength. To address this limitation, PLA fabric was treated with an eco-friendly natural deep eutectic solvent (NaDES) composed of glycerol and citric acid. The treatment was found to enhance fiber surface roughness and internal looseness, which facilitated dye diffusion and allowed for a significant reduction in dyeing temperature. When dyed with microbial prodigiosin, the treated PLA fabric achieved a color depth at 70 °C that was equivalent to untreated fabric at 90 °C, while also exhibiting a 93.56% bacteriostatic rate against Staphylococcus aureus due to the inherent antibacterial property of microbial prodigiosin. This work provides a novel and sustainable strategy for the eco-friendly dyeing of PLA textiles.

Sea Island cotton (Gossypium barbadense) produces premium-quality fibres, yet the genetic basis underlying its fibre development remains elusive. Here, we identify two key non-synonymous single nucleotide polymorphisms (SNPs, G/C and G/A) in the gene Gbar_D13G024080, which encodes the TRANSMEMBRANE PROTEIN 209 (TMEM209). These SNPs resulted in amino acid changes (V/L and R/K), and are significantly correlated with the fibre length in Sea Island cotton. CRISPR-Cas9-mediated knockout of GbTMEM209 significantly enhanced fibre length and fibre strength in both G. hirsutum and G. barbadense. Conversely, overexpression of GbTMEM209 in G. hirsutum led to reduced fibre length. Further mechanistic investigation revealed that GbTMEM209 competitively interacts with GbHOX3 to impair its transcriptional activation on cell wall-loosening genes GbEXPA1 and GbRDL1. Moreover, during the elongation stage of the fibres, GbTMEM209 and GbHOX3 exhibit an antagonistic relationship, which jointly regulate the development of cotton fibres. Virus-induced gene silencing (VIGS) of GbHOX3, GbEXPA1, or GbRDL1 consistently resulted in shortened fibres in Sea Island cotton, validating their critical roles in fibre development. Our findings establish GbTMEM209 as a novel negative regulator of fibre elongation and uncover a protein competition-mediated transcriptional control mechanism in cotton fibre morphogenesis. These findings provide valuable genetic targets and conceptual insights for molecular breeding programs aimed at improving cotton fibre quality.

This study analyzes the influence of porosity on Nextel TM 610/Al 2 O 3 -ZrO 2 short-fiber-reinforced composites for the first time. Its goal was the comparison of a short-fiber-reinforced all-oxide ceramic matrix composite (SF-Ox/Ox) with a fabric-reinforced material. Since the matrix system and the processing were the same for both materials, differences can be related to the use of short-fibers instead of fabrics. Zirconium-n-butoxide was infiltrated to decrease the porosity from 32% to 46%, which increased the bending strength and the Young’s modulus from 85±19 MPa to 120±23 MPa and 40±10 GPa to 82±12 GPa, respectively. The strain decreased with decreasing porosity from 0.25±0.05% to 0.16±0.03%. The damage-tolerant behavior was maintained for all samples, which was never shown for SF-Ox/Ox in such a porosity range. The less anisotropic alignment of the short-fibers is therefore advantageous for crack-deflection. This offers the possibility to obtain damage-tolerance while having a denser matrix system.

This study examines the effects of natural seawater ageing on mechanical properties, including tensile strength and flexural strength of flax fiber reinforced polymers (FFRP). Specimens were subjected to a natural seawater environment in periods of exposure of one, three, and five months, as well as a reference group that was kept at room temperature. Water absorption and desorption were measured by weighing the specimens before and after exposure. All submerged specimens exhibited varying levels of microorganisms and adhering algae attachment to the material surface, as well as subsequent growth rates. Both tensile and flexural properties were measured and compared to reference specimens, which were kept in a dry room environment. Various levels of ultimate tensile strength (UTS) degradation were observed for different exposure times for tensile testing specimens, as well as a reduction in maximum flexural strain for three-point bending test specimens.

ABSTRACT Aimed at the key problems of the performance and application of continuous fiber reinforced composite filaments in additive manufacturing, this study clarified that fiber desizing was a key variable affecting the impregnation quality, interface bonding and final filament performance. By systematically characterizing the mechanical properties, microstructure and surface chemistry of glass fibers at different heat treatment temperatures, and analyzing the effects of desizing temperature, mold temperature and traction speed on the forming quality of filaments, the interaction mechanism between fiber surface state and impregnation process conditions was revealed. It was found that the tensile strength of glass fiber decreased significantly after heat treatment above 200°C, and the strength decreased to 787.15 MPa at 350°C, a decrease of 52.12%, which was mainly attributed to the internal structure damage and surface defects of the fiber. Moderate heat treatment (such as 100°C) could increase fiber surface active groups, improve the interface bonding, and improve the comprehensive performance of the filament. This study decoupled the relationship between fiber surface modification, process parameters and composite properties, and provided new insights and experimental basis for directional regulation of composites properties and further improvement of its engineering application potential.

The high fiber strength (FS) of a Upland cotton cultivar bred by interspecific cross was found to be associated with a D11 QTL and the identification of a candidate gene, and a genetic variant provides a potential tool for molecular breeding of high FS cotton cultivars. Fiber strength (FS) is one of the critical determinants of cotton fiber quality. Despite many quantitative trait loci (QTLs) associated with FS have been documented, many more are yet to be uncovered. In this study, an F2 population was constructed by crossing Huiyuan720 (Gossypium hirsutum) with Shida26-22, a high FS G. hirsutum cultivar bred by introgressing the high FS trait of G. barbadense cultivar Xinhai53 into Huiyuan720 via multiple backcrosses. Bulked segregant analysis sequencing of the F2 population identified six FS QTLs, including a major locus on chromosome D11 spanning 3.38Mb containing 121 annotated genes. By integrating transcriptome sequencing of developing fibers, analyzing gene co-expression network, and profiling genetic variants of annotated genes, GH_D11G2131, annotated to encode an armadillo repeat/tetratricopeptide repeat-like protein, was identified as a strong candidate gene potentially regulating FS. GH_D11G2131 harbored a non‑synonymous mutation and a promoter indel between the two parents, belonged to a co‑expression gene module highly correlated with cell wall development, and was significantly highly expressed in 20days post‑anthesis fibers of high FS cultivars. Virus-induced gene silencing demonstrated that knockdown of GH_D11G2131 resulted in thinner secondary cell walls and a significant reduction in lignin content, thanks to the marked downregulation of genes related to lignin biosynthesis. Collectively, this study uncovered a major FS QTL and a strong candidate gene associated with SCW development, providing a potential molecular tool for breeding elite cotton cultivars with high fiber quality.