This review rigorously analyzes the advancement of fiber-reinforced geopolymer plasters for fireproofing purposes in construction. Geopolymers possess superior thermal resistance and reduced environmental impact relative to ordinary Portland cement. The addition of fibers such as steel, glass, basalt, and synthetic materials markedly improves mechanical strength, thermal insulation, and fire resistance. Recent research is comprehensively summarized, focusing on the mechanical behavior, thermal conductivity, microstructural evolution, and degradation mechanisms of fiber-reinforced geopolymers subjected to elevated temperatures and fire exposure. Special emphasis is placed on intumescent properties and fire-protection mechanisms that support the prospective advancement of geopolymer-based surface protection plasters. This review delineates significant research deficiencies, such as long-term durability, fiber–matrix interactions under cyclic thermal loading, and standardized fire-testing protocols, while also addressing burgeoning prospects for artificial intelligence-assisted material design and performance forecasting. Fiber-reinforced geopolymers are identified as a viable low-carbon fireproofing material that meets the sustainability and safety requirements of contemporary construction.
Post-recycling plastic waste contamination in freshwater ecosystems represents an escalating environmental threat, while algal blooms continue to generate vast quantities of underutilized biomass. Addressing both challenges, this study investigated the co-hydrothermal liquefaction of Chlorella pyrenoidosa with representative post-recycling plastic wastes polypropylene, polyethylene terephthalate, and Nylon-6 as a dual-resource valorization strategy. Experiments were conducted in a 1000 mL high-pressure batch reactor at 350 degrees C for 30 min, with varying biomass-to-plastic feed ratios. Systematic product characterization, including functional group, elemental analysis, Van Krevelen diagrams, and heating value assessment, was employed to elucidate synergistic effects and evaluate product quality. Results revealed that co-processing with polyethylene terephthalate achieved the highest biocrude yield of 71.5%, with an enhanced higher heating value of 35.7 MJ kg-1, surpassing the 62.4% yield from microalgae alone. Nylon-6 blends also improved oil yield to 69.6% while producing aqueous fractions enriched with epsilon-caprolactam, indicating the recovery of valuable nitrogenous monomers. In contrast, PP exhibited limited reactivity toward oil generation but produced carbon-rich biochar with a higher heating value up to 41.4 MJ kg-1, comparable to high-grade solid fuels. Mechanistic analyses confirmed that plastics acted as hydrogen donors, promoting deoxygenation, radical stabilization, and selective depolymerization, thereby improving both liquid and solid fuel fractions. By employing ecologically relevant freshwater feedstocks from Thailand, this work advances beyond prior studies dominated by marine biomass or synthetic surrogates, providing realistic insights into resource integration within polluted inland waters. The co-hydrothermal liquefaction process simultaneously mitigates eutrophication-driven algal blooms and persistent plastic pollution while generating fuels and functional carbon materials, directly contributing to a circular bioeconomy. The demonstrated synergy between biological and synthetic wastes highlights a scalable, catalyst-free route to energy-dense biofuels and multifunctional biochar. These outcomes align strongly with SDG which offer a pragmatic framework for waste-to-energy transition in freshwater-dependent regions.
We realize optical vortex beams with fractional orbital angular momentum (OAM) states generated by a spatial light modulator (SLM) and analyze them using the near-field Talbot effect as a diagnostic tool. In our recent setup, the Bessel vortex beam is converted to a Gaussian beam by lenses to achieve sharper vortex imaging. Our experimental results clearly indicate that the interference Talbot patterns can distinguish different fractional OAM states. We also conducted numerical simulations that agree well with the experimental results. These results suggest potential applications in classical structured-light systems, such as beam diagnostics, optical manipulation (e.g., optical tweezers), and micro- and bio-scale applications. Possible extensions to quantum-related applications, such as high-dimensional encoding in quantum communication, may be explored with appropriate single-photon implementations.
Any perturbation to the neurohormonal-immune system during the fetal developmental period carries over effects later in life. Prenatal stress (PS) induces hippocampal changes in the structure and functions that could lead to cognitive impairment and psychiatric disorders. Increasing evidence indicates that physical exercise could ameliorate cognitive impairment in both young and old rats. We investigated the therapeutic effect of the postnatal voluntary wheel running (VWR) exercise on cognitive impairment that developed from prenatal maternal restraint stress. The restraint stress was carried out during gestation day (GD)14-21 in the pregnant Sprague-Dawley rats. VWR was performed in the rat pups on postnatal day (P)25-40. After that, spatial memory performance was tested with the Morris water maze (MWM) during P36-40. The effect of prenatal stress and the potential effects of the VWR on the levels of hippocampal synaptic proteins, brain-derived neurotrophic factor (BDNF), and interleukin (IL)-6 in the rat offspring were ascertained with Western blot analysis. Stress during the prenatal period induced decreases in synaptic proteins and BDNF, but an increase in IL-6. Postnatal exercise ameliorated the adverse effects of PS on protein expression. The MWM test confirmed the ameliorative effect of VWR on spatial memory performance of the pups. Our findings suggest that postnatal exercise has a high potential to ameliorate the adverse effects of maternal stress and return healthy neuroendocrine-immune system and spatial memory to rat offspring.
This study examined the immediate effects of long-duration static stretching on range of motion (ROM), muscle–tendon unit (MTU) stiffness, and muscle strength in older adults with hamstring tightness and possible sarcopenia. Sixty-eight older adults (67.2 ± 4.5 years) were randomly assigned to long-duration static stretching (LS), standard-duration static stretching (SS), eccentric exercise (ECC), or control. Joint ROM, fascicle length (FL), MTU stiffness, and knee-flexor peak eccentric torque were assessed at baseline and immediately after a single intervention. Significant immediate ROM improvements were observed in the LS, SS, and ECC groups (5.5°, 5.6°, and 3.1°, respectively; all p < 0.05), with no between-group differences. MTU stiffness decreased significantly after LS (median: −0.05 Nm/deg) and SS (median: −0.06 Nm/deg; both p < 0.05), whereas no changes were observed in the ECC or control groups. No significant changes in FL were detected, indicating that ROM improvements were not associated with alterations in muscle architecture. A significant main effect of time was found for knee-flexor peak eccentric torque, with no group × time interaction. A single 30-min session of hamstring stretching did not produce greater acute improvements in ROM, MTU stiffness, or muscle strength than shorter-duration stretching or eccentric exercise. However, the magnitude of these effects did not exceed the threshold for clinical meaningfulness, as defined in the present study. Further refinement of intervention parameters (e.g., position, or intensity) may be required to elicit clinically meaningful changes in ROM in tight and possible sarcopenic muscles.
