Volume 21 Issue 2

This review considers published evidence supporting ways in which self-assembly and interdigitated structures that emerge during sheet formation contribute to mechanical strength and structural development in nanopaper and conventional paper-like sheets. Interdigitation is defined here as a form of three-dimensional connectivity within fibrous networks, including elements of parallel interaction, minor weaving, physical entanglement, and inter-diffusion among fibers, fibrils, and nano-scale cellulosic features of multiple length scales. Particular attention is given to out-of-plane fiber orientations and the persistence of three-dimensional connectivity during sheet formation, features that are not fully captured by idealized two-dimensional network models. The review considers mechanical, rheological, microscopic, and processing-related studies to assess how hydrodynamic conditions, flocculation, consolidation history, and drying influence the formation and effectiveness of interdigitated structures. The collected evidence suggests that interdigitation is an inherent feature of papermaking over a broad range of fiber and fibril dimensions, and that it can be strongly influenced by processing conditions.  In addition to highlighting the topic of interdigitation, this review also reveals a need for more detailed theoretical consideration, as well as focused experimental work.

Northwestern Iran represents a significant data gap in the dendroclimatic network of West Asia, hindering a comprehensive understanding of regional hydroclimatic variability. This study aims to bridge this gap by constructing a robust tree-ring width chronology for Juniperus excelsa and evaluating its response to climatic extremes in the Hashtjin mountains of northwestern Iran. The authors analyzed 19 increment cores from 15 old-growth trees to develop a 110-year chronology (1898–2007). Statistical quality indicators confirmed a robust climatic signal. Analysis revealed that radial growth was primarily constrained by moisture availability, showing significant positive correlations with April and June precipitation and a significant negative correlation with April temperature, highlighting spring drought stress. Temporal instability in these climate-growth relationships was detected using moving window correlation. Four independent methods (IT, RGC, NW, zChron) identified major pointer years, with extreme droughts in 1907–1908 and 2001 consistently flagged. These extreme years show strong spatiotemporal coherence with historical drought records across West Asia and the Eastern Mediterranean, validating the chronology’s climatic sensitivity and underscoring regional synchronicity in major hydroclimatic events. The findings underscore the vulnerability of juniper ecosystems to warming-induced drought and provide a crucial proxy for filling paleoclimatic gaps in the region.

Fused deposition modeling (FDM) 3D printing technology was used to customize furniture risers to match furniture dimensions and children’s body sizes. The goal was to achieve a rapid, safe, and sustainable height adjustment solution for children’s furniture. Polyamide (PA) filament was chosen as the printing material. Compression tests were performed to investigate the properties of the 3D-printed PA models under varying process parameters, including layer thickness, infill density, and heated bed temperature. Experiments showed that as the layer thickness decreased, the infill density and the heated bed temperature increased. The compressive strength and compressive modulus of the PA model gradually increased, and the compressive properties improved. The optimized process parameters for compressive properties were: layer thickness (0.1 mm), infill density (90%), and heated bed temperature (90 °C). Using these parameters, this study completed the fabrication of furniture risers via FDM 3D printing. The 3D-printed furniture risers exhibited excellent compressive strength and surface finish, and they allowed for quick height adjustment to accommodate children’s varying body sizes. Moreover, the 3D printing approach itself was cost-effective and highly efficient. These benefits collectively highlight the application value of 3D printing for customized furniture components in promoting children’s healthy growth and saving resources.

A facile, scalable, and bioinspired approach was used to create a high-performance, biodegradable motion sensing through the construction of a scaly conductive coating on regenerated cellulose fibers (RCFs) derived from bacterial cellulose. A single-step dip-coating process enabled the in situ self-assembly of copper nanoplates and silver nanoparticles into a multilayered, overlapping architecture during controlled fiber withdrawal, mimicking the flexible yet robust structure of fish scales. The obtained Cu/Ag-RCFs sensor exhibited an exceptional balance of mechanical durability, electrical conductivity, and tunable electromechanical response. Their sensitivity and dynamic range could be precisely tailored by adjusting the number of coating cycles, with the optimized device (4 cycles) delivering stable, reversible, and highly reproducible resistance changes under both bending and tensile deformations. Practical applicability was demonstrated through preliminary demonstrations, including successful integration into a glove for real-time finger gesture recognition and deployment as a vibration monitor for intelligent logistics. Critically, the cellulose-based substrate ensured environmental sustainability, maintaining operational stability in aqueous environments while enabling rapid, complete degradation in acidic or enzymatic conditions. This work establishes a novel paradigm for sustainable electronics that harmonizes bioinspired design, high sensing performance, and end-of-life biodegradability.

Effects of different surface treatments were studied relative to the moisture absorption, tensile strength, and interfacial strength were compared for bamboo fibers with epoxy resin. The results showed that the bamboo fibers treated with palm oil had relatively good hydrophobicity and bonding strength with epoxy, and less influence on the tensile strength. Palm oil treatment at 150 °C decreased the strength of bamboo fibers, but it enhances the strength of angled bamboo fibers compared to that without oil treatment. Subsequently, tensile strength retention of angle-shaped bamboo fibers was investigated. The results showed that bamboo fibers treated with palm oil before preforming was able to improve the tensile strength after forming (from 222 to 252 MPa). The study also highlighted the process sequence of the surface treatments for improved strength retention after forming.

The transfer of heavy metals (HMs) was investigated from wastewater used for irrigation to soil and subsequently to rice plants (Oryza sativa L.) in Northern Pakistan, a region where rice is widely consumed. The concentrations of cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn) were measured in irrigation water, soil, and different parts of the rice plant (grain, shoot, and root) collected from various paddy fields. To assess potential health risks, daily metal intake (DIM) and the health risk index (HRI) were calculated. Heavy metal concentrations varied significantly across sampling locations. In the soil, Cd ranged from 0.1 to 0.49 mg/kg, Pb from 0.8 to 2.2 mg/kg, Cu from 4.2 to 18.2 mg/kg, and Zn from 7.0 to 25.1 mg/kg. The calculated DIM followed the order Zn < Cd < Cu < Pb, while the overall HRI for adults (0.612) and children (0.533) were below the threshold of 1. However, cadmium concentrations in the studied samples exceeded suggested permissible limits. Statistically significant differences (P < 0.05) revealed higher HM concentrations in the soil and rice crops from paddy fields irrigated with contaminated wastewater compared to a control site. The findings of this study indicate that the use of wastewater for irrigation leads to increased accumulation of HMs, particularly cadmium, in rice grains, potentially posing health risks to consumers in the region.

As a commonly used method in the field of structural dynamic characteristics, mode shape identification currently relies largely on animation demonstrations of finite element modal analysis. This method is highly susceptible to the observer’s perspective and subjective factors, making it difficult to accurately identify the mode shapes of timber pieces. To address this issue, the plane deformation decomposition theory of 2D-4 node quadrilateral elements was adopted to perform relative rigid body displacement decomposition on mode shapes, thereby achieving quantitative and visual identification of the overall mode shapes of timber pieces. The correctness of the proposed method was verified by comparison with the modal mass participation ratio method. In addition, this method can also determine the dominant rigid body displacement type of each element in the mode shapes of timber pieces, which highlights its superiority.

Banana peels are rich in phytochemicals, including tannins, phenolic compounds, flavonoids, glycosides, saponins, and terpenoids. This study focused on the use of unripe banana peels of Musa × paradisiaca var. Monthan for the extraction of total phenolic content (TPC) and total flavonoid content (TFC). Three independent variables (solid‒solvent ratio, ethanol concentration, and extraction time) were selected for optimizing the ultrasound-assisted extraction of the TPC and TFC via response surface methodology. The banana peel extract presented a maximum TPC and TFC of 68.2 mg GAE/g and 15.4 QE/g, respectively, when extracted under the following extraction conditions: a 6% solid‒solvent ratio, 50% ethanol, and 40 min extraction time. Banana peels showed 75.4±2.1% inhibition in the DPPH assay and 59.9±1.1% inhibition in the ABTS assay at a concentration of 100 µg/mL. Banana peels presented significant enzyme inhibitor activity. The IC₅₀ values of the α-amylase and α-glucosidase inhibitory activities of the peel extract were 7.4±0.2 mg/mL and 9.5±0.09 mg/mL, respectively. Banana peel extract suppressed the synthesis of proinflammatory cytokines such as IFN-γ, IL-1α, TNF-α, and IL-6 and upregulated the synthesis of anti-inflammatory cytokines (IL-13 and IL-10). Banana peel can be utilized for its anti-inflammatory, antioxidant, and antidiabetic activities.

Ozonation has emerged as an effective approach to enhance the biological efficacy of plant-derived oils through chemical modification. In this study, crude and ozonated Ziziphus spina-christi oils were chemically characterized by gas chromatography–mass spectrometric (GC-MS) analysis and evaluated in vitro for their biological activities. GC–MS profiling revealed that the crude oil consisted predominantly of oxygenated monoterpenes and aromatic esters, particularly eucalyptol and methyl salicylate, along with lower proportions of fatty acids and their derivatives. Following ozonation, a marked increase in oxygenated compounds was observed, including epoxidized fatty alcohol esters and alkyl ether alcohols. Ozonated oil showed pointedly enhanced antibacterial activity, minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC), with inhibition zones of 37.0 ± 0.6, 31.0 ± 0.1, 25.0 ± 0.8, and 29.0 ± 0.8 mm against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi, respectively. Ozonated oil inhibited biofilm formation by more than 80% at sub-MBC levels and reduced bacteria-induced hemolysis by up to 98.1% at 75% MIC. Time-kill kinetics confirmed rapid bactericidal effects within 180 min. Moreover, ozonated oil exhibited superior anti-inflammatory activity with an IC₅₀ of 2.40 ± 0.09 µg/mL. These findings highlight ozonated Z. spina-christi oil as a promising multifunctional bioactive agent.

Lycium ruthenicum polysaccharides (LRP) are known to possess antioxidant effects. However, a systematic evaluation across chemical, cellular, and in vivo models have been lacking. The underlying metabolomic mechanisms also remain unexplored. This study systematically evaluated the antioxidant effects of LRP through in vitro assays, H₂O₂-induced AML12 hepatocytes, and liver tissue from mice, supplemented by untargeted metabolomic analysis of cell extracts to explore LRP’s antioxidant mechanisms. Results showed that LRP possessed significant oxygen radical absorbance capacity and potent scavenging activity against ABTS•⁺, DPPH•, and •OH radicals in vitro. In AML12 cells, LRP increased activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GSH-Px), while effectively reducing intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels (P<0.05). In mouse liver tissues, LRP may have slightly improved SOD and CAT levels while decreasing MDA levels (P>0.05). Furthermore, untargeted metabolomics revealed that LRP attenuated oxidative damage by modulating metabolic pathways, particularly glutathione metabolism, the tricarboxylic acid (TCA) cycle, and amino acid metabolism. These findings confirm the significant antioxidant potential of LRP, supporting its promise as a functional food ingredient.