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Funding Information: D.J.-A. thanks the European Commission for the Marie Sklodowska Curie contract (101025125). R.P.S. thanks Cabildo de Tenerife for the postdoctoral contract within the “Programa Talentum Innovación CSIC”. Publisher Copyright: © 2025 by the authors. Climate change is reducing agricultural productivity through altered weather patterns and extreme events, potentially decreasing yields by 10–25%. Biostimulants like pyroglutamic acid can enhance plant tolerance to water stress, but their rapid degradation in the soil limits effectiveness. Encapsulation in alginate matrices promises to be a good solution, protecting the compound and enabling controlled release. This study reports, for the first time, that encapsulated pyroglutamic acid markedly enhances drought tolerance in tomato and maize plants. The encapsulation strategy reduces effective concentration by an order of magnitude while significantly improving water use efficiency, photo-synthetic performance, and overall stress resilience. These findings demonstrate that alginate-based encapsulation substantially increases biostimulant uptake and efficacy, providing a novel and efficient strategy to mitigate water stress in crops, with important implications for climate-resilient agriculture. Two encapsulation methods for generating the alginate microcapsules are compared: ionic gelation with Nisco® system and the electrospray technique.

Funding Information: This project was funded by the PhD Fellows grant awarded by the Fundação para a Ciência e Tecnologia, I.P., with the project references 2021.08511.BD and 2020.05529.BD and DOI identifiers https://doi.org/10.54499/2021.08511.BD and https://doi.org/10.54499/2020.05529.BD. This research was also supported by the Associate Laboratory for Green Chemistry—LAQV—which received financial support from the FCT/MCTES (LA/P/0008/2020 DOI 10.54499/LA/P/0008/2020, UIDP/50006/2020 DOI 10.54499/UIDP/50006/2020 and UIDB/50006/2020 DOI 10.54499/UIDB/50006/2020) using national funds. This work was also funded by national funds provided by the FCT—Fundação para a Ciência e a Tecnologia—I.P., under project UIDB/04129/2020 of the LEAF—Linking Landscape, Environment, Agriculture and Food—Research Unit. Publisher Copyright: © 2025 by the authors. Arabinoxylan is a polysaccharide with film-forming properties, present in corn fiber, and a low-value by-product. The extract has a deep brown color, producing films of the same shade, which may not be appealing. This study addresses, for the first time, the adsorption of colored compounds present in an arabinoxylan extract using resin MN102. The resin successfully adsorbed the colored compounds from the arabinoxylan extract. After four consecutive adsorption/desorption cycles, the efficiency of the resin was similar, only decreasing from 63.3% to 52.9%. Langmuir and Freundlich models were fitted to the results of adsorption isotherm experiments, with the Freundlich model demonstrating the best fit to the experimental results. A fixed-bed column loaded with the resin was used for the removal of the colored compounds from the arabinoxylan extract, and the effect of the volumetric flow rate was investigated. The Yan and log-Gompertz models showed the best fit to the experimental breakthrough curves. This study systematically evaluated the adsorption conditions, providing a comprehensive analysis of the performance of the resin in the removal of the colored compounds. Additionally, the ability of the extract to maintain its film-forming properties after decolorization was evaluated, and some of the film’s key characteristics were evaluated, namely its color, solubility in water and mechanical properties.

Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions.

Fiber-reinforced polymer composites (FRPs) experience exposure to diverse environments throughout their intended design life. Investigating the aging process of FRPs immersed in water is crucial for enhancing the material's durability. In this study, glass fiber, bamboo fiber, nanoclay and epoxy composites are produced using the hand lay-up process. Tensile and flexural tests are performed in adherence to ASTM standards. The water uptake percentage of soaked specimens is computed, and a comparison is drawn between the results of dry and water-immersed composite specimens. Water-soaking condition negatively affects all the composites. Water-soaked specimens exhibit lesser tensile and flexural strengths than dry specimens by 7.4-14.8% and 7-13.6%, respectively. The addition of nanoclay further improves the tensile and flexural strengths of epoxy and all composites by 6-11%. Water uptake (%) and water-soaking effects on the strength of composites decline when nanoclay is added. The addition of nanoclay declines the percentage of reduction of tensile strength from 8.6-14.8% to 7.4-12%. Similarly, the percentage of flexural strength reduction declines from 8-13.6% to 7-11%. The dry and water-soaked specimens' fracture surfaces (Scanning Electron Microscope [SEM] images) show significant variations.

Bioprinting approaches are of great promise for tissue engineering applications as they allow the fabrication of constructs able to mimic native tissues’ mechanical and topographical features. Additional control over cells fate can be enhanced using stimuli-responsive materials, requiring the development of novel bioinks for this purpose. In this study, bioinks comprising κ-carrageenan, collagen, and magnetic nanoparticles were designed for 3D bioprinting applications. The characterization of this material was performed, where mechanical compressive tests yielded Young’s moduli ranging from 8.25 to 18.4 kPa. Rheological assessments also revealed the shear-thinning behavior of the bioinks and a temperature-dependent gelation. The capability of these bioinks to produce 3D constructs by extrusion bioprinting was established through the printability evaluation and the development of complex structures, supporting the viability and proliferation of mesenchymal stromal cells (MSCs). Finally, as proof-of-concept, it was observed that the secretome of bioprinted MSCs stimulated with an external magnetic field of 80 mT was able to increase the number of tubes formed by human umbilical vein endothelial cells.

The study presented herein concerns the mechanical properties of two common polymers for potential biomedical applications, PLA and PETG, processed through fused filament fabrication (FFF)—Material Extrusion (ME). For the uniaxial tension tests carried out, two printing orientations—XY (Horizontal, H) and YZ (Vertical, V)—were considered according to the general principles for part positioning, coordinates, and orientation typically used in additive manufacturing (AM). In addition, six specimens were tested for each printing orientation and material, providing insights into mechanical properties such as Tensile Strength, Young’s Modulus, and Ultimate Strain, suggesting the materials’ potential for biomedical applications. The experimental results were then compared with correspondent mechanical properties obtained from the literature for other polymers like ASA, PC, PP, ULTEM 9085, Copolyester, and Nylon. Thereafter, fatigue resistance curves (S-N curves) for PLA and PETG, printed along 45°, were determined at room temperature for a load ratio, R, of 0.2. Scanning electron microscope observations revealed fibre arrangements, compression/adhesion between layers, and fracture zones, shedding light on the failure mechanisms involved in the fatigue crack propagation of such materials and giving design reference values for future applications. In addition, fractographic analyses of the fatigue fracture surfaces were carried out, as well as X-ray Computed Tomography (XCT) and Thermogravimetric (TGA)/Differential Scanning Calorimetric (DSC) tests.

The extraction of collagen from fish skins is being proposed as strategy for valorization of marine origin by-products, being a sustainable alternative to mammal collagen. The method commonly uses solutions of organic acids, but new methodologies are arising, aiming to improve process yields and/or the properties of the resulting products. In this work, skins removed from salt brine Atlantic cod (Gadus morhua) were used to extract collagen, using water acidified with CO2, obtaining an extraction yield of 13.8% (w/w). Acidified water extracted collagen (AWC) presented a total content of proline-like amino acids of 151/1000 residues, with a degree of hydroxylation of 38%, and its SDS-PAGE profile is compatible with type I collagen. Moreover, FTIR, CD and XRD results suggest the presence of preserved triple helix, having a denaturation temperature of 32.3 °C as determined by micro-DSC. AWC exhibited a typical shear thinning behavior, interesting regarding their further processing, namely in jelly-like formulations. Additionally, the presence of AWC in MRC-5 human fibroblasts culture did not affect cell viability, demonstrating the non-cytotoxic behavior. Overall, the results support the efficiency of the proposed approach for collagen extraction and further enable the design of methodologies to address AWC use in biomedical or cosmetic context.

Fe–Mn–Si–Cr–Ni shape memory alloys (SMAs) are unique low-cost materials with shape memory properties that grant them the ability to be used in both functional and structural applications. Such SMAs are especially sought in the construction sector for the creation of new components and/or the reinforcement of damaged ones. In this study, a Fe–17Mn–5Si–10Cr–4Ni–1(V, C) wt% SMA was gas tungsten arc welded, with the objective to investigate the microstructure and mechanical performance changes occurring after welding. A comprehensive assessment of processing, microstructure and properties relationships was established combining microscopy (optical and electron), synchrotron X-ray diffraction, microhardness mapping and tensile testing including cycling assessment of the joint’s functional performance. It is shown that the present SMA has good weldability, with the joints reaching nearly 883 MPa at fracture strain of 23.6 ± 2.1%. Alongside this, several microstructure differences were encountered between the as-received and as-welded condition, including the formation of ferrite and Fe 5 Ni 3 Si 2 P2 1 3 cubic precipitates amidst the fusion zone in the latter region. Graphical abstract

High-entropy alloys (HEAs) are increasingly preferred as structural materials in nuclear engineering and aerospace applications. These fields often require the design of dissimilar joints. Here, gas tungsten arc welding (GTAW) was used for the first time to join CoCrFeMnNi HEAs with 316 stainless steel. Microstructural characterization, including electron microscopy, high-energy synchrotron X-ray diffraction, and thermodynamic calculations, along with micro- and macroscale mechanical assessments, was utilized. These methods were instrumental in evaluating and clarifying the effects of the non-equilibrium solidification and weld thermal cycle on the microstructure evolution of the joint. In the fusion zone (FZ), distinctive peninsula-shaped macroscopic segregation area is observed, with its formation being related to the liquidus temperature differences between the base materials (BMs) and the welded metal, compounded by the Marangoni effect. The weld thermal cycle was found to promote multiple solid-state phase transformations in the heat-affected zone (HAZ) adjacent to the CoCrFeMnNi BM, leading to varying degrees of softening. The HAZ near the 316 stainless steel BM maintained its original microstructural and mechanical properties. Fracture predominantly occurred in the FZ, mainly due to the interplay of large columnar grains, macrosegregation effects, and emergence of BCC and σ brittle phases due to the complex chemistry within this region. Thermodynamic modeling validated the formation of these phases. The ultimate tensile strength and elongation at room temperature were approximately ≈493 MPa and ≈10.70%, respectively.

The interfacial topography of biomaterials has been identified as a major biophysical regulator of cell behavior and function, a role played through the interplay with biochemical cues. In this work, we demonstrate the potential of laser as a versatile technology for the direct fine-tuning of the topography of Bacterial nanocellulose (BNC) with bioinspired topographies and micropatterns on a cell size scale. Two lasers were used, with different wavelengths—IR (CO2, 10600 nm) and UV (tripled Nd: YVO4, 355 nm) —attempting to reproduce the Pitcher-plant topography and to create cell-contact guidance patterns, respectively. Different topographies with parallel grooves featuring a 20–300 μm period were generated on the BNC surface with high fidelity and reliability of the generated microstructures, as demonstrated by 3D optical profilometry and scanning electron microscopy. Moreover, it was demonstrated by X-ray photoelectron spectroscopy that laser processing does not result in detectable chemical modification of BNC. The developed anisotropic microstructures can control cell behavior, particularly regarding morphology, alignment, and spatial distribution. Thus, this proof-of-concept study on the high-resolution laser patterning of BNC opens new perspectives for the development of cell-modulating laser-engineered BNC interfaces, scaffolds, and other advanced medical devices, which can potentially broaden the application of BNC in the biomedical field.