The exploration of the Moon necessitates sustainable habitat construction. Establishing a permanent base on the Moon requires solutions for challenges such as transportation costs and logistics, driving the emphasis on In-Situ Resource Utilization (ISRU) techniques including Additive Manufacturing. Given the limited availability of regolith on Earth, researchers utilize simulants in laboratory studies to advance technologies essential for future Moon missions. Despite advancements, a comprehensive understanding of the fundamental properties and processing parameters of sintered lunar regolith still needs to be studied, demonstrating the need for further research. Here, we investigated the fundamental properties of lunar regolith simulant material with respect to the stereolithography-based AM process needed for the engineering design of complex items for lunar applications. Material and mechanical characterization of milled and sintered LHS-1 lunar regolith was done. Test specimens, based on ASTM standards, were fabricated from a 70 wt% (48.4 vol %) LHS-1 regolith simulant suspension and sintered up to 1150 degrees C. The compressive, tensile, and flexural strengths were (510.7 +/- 133.8) MPa, (8.0 +/- 0.9) MPa, and (200.3 +/- 49.3) MPa respectively, surpassing values reported in previous studies. These improved mechanical properties are attributed to suspension's powder loading, layer thickness, exposure time, and sintering temperature. A set of regolith physical and mechanical fundamental material properties was built based on laboratory evaluation and prepared for utilization, with the manufacturing of complex-shaped objects demonstrating the technology's capability for engineering design problems.

The solidification and molding of lunar regolith are essential for constructing lunar habitats. This study introduces an innovative lunar regolith molding technique that synergistically combines solar concentration, flexible optical fiber bundle energy transfer, and powder bed fusion. A functional prototype is developed to validate the proposed scheme. Systematic experiments including fixed beam spot melting, line melting, surface melting, and body melting are conducted using simulated basalt lunar regolith. Through in-situ observation of the melt pool's formation, evolution, and expansion dynamics, we identify a sequential transformation mechanism on the powder bed's surface: initial curling evolves into detachment from the bed, subsequent incorporation into a molten droplet, and ultimate solidification. A comprehensive evaluation of density and mechanical properties across multiple parameter combinations reveals that energy flux density of 3.33 MW/m2 with a scan speed of 30 mm/min, inter-track spacing of 3 mm, and layer thickness of 2 mm enables the production of structurally integral samples with continuous morphology. The resulting specimens demonstrate a maximum compressive strength of 4.25 MPa and a density of 2.31 g/cm3. This solar-powered additive manufacturing approach establishes a viable reference framework for large-scale on-site construction of lunar research stations.

The construction industry faces significant challenges, including the urgent need to minimize environmental impact and develop more efficient building methods. Additive manufacturing, commonly known as 3D-printing, has emerged as a promising solution due to its advantages, such as rapid fabrication, design flexibility, cost reduction, and enhanced safety. This technology enables the creation of structures from digital models through automated layering, presenting opportunities for mass production with innovative materials and architectural designs. This article focuses on developing eco-friendly earthen-based materials stabilized with 9 % cement and 2 % rice husk (RH) for large-scale 3D-printed construction. The raw materials were characterized using geotechnical tests for soil, water absorption tests for natural fibers, and SEM-EDS to examine their microstructure and elemental composition. Key properties such as rheology, printability (pumpability and extrudability), buildability, and compressive strength were evaluated to ensure the material's optimal performance in both fresh and hardened states. By utilizing locally sourced materials such as soil and rice husk, the mixture significantly reduces environmental impact and production costs, making it a sustainable alternative for large-scale 3D-printed construction. The material was integrated into architectural and digital fabrication techniques to construct a bioinspired housing prototype showcases the practical application of the developed material, demonstrating its scalability, adaptability, and suitability for innovative and costeffective real housing solutions. The article highlights the feasibility of using earthen-based materials for sustainable 3D-printed housing, thereby opening new possibilities for advancing greener construction practices in the future.

Considerable losses are inflicted by plant-parasitic nematodes (PPNs) due to their obligate parasitism; serious damage occurs in many susceptible crops, and the parasites have a broad distribution worldwide. As most PPNs have a subterranean nature, the complexity of soils in the plant rhizosphere and the structures and functions of the soil food webs necessitate a grasp of the relevant biotic/abiotic factors in order to ensure their effective control. Such factors frequently lead to the inconsistent performance and untapped activity of applied bionematicides, hindering efforts to develop reliable ones. Research efforts that take these factors into account to back the usage of these bionematicides by combining the disease-suppressive activities of two or more agricultural inputs are highlighted herein. These combinations should be designed to boost useful colonization in the rhizosphere, persistent expression of desirable traits under a wide range of soil settings, and/or antagonism to a larger number of plant pests/pathogens relative to individual applications. Relevant ecological/biological bases with specific settings for effective PPN management are exemplified. Determining the relative sensitivity or incompatibility of some biologicals entails studying their combinations and reactions. Such studies, as suggested herein, should be conducted on a case-by-case basis to avoid unsatisfactory outputs. These studies will enable us to accurately define certain outputs, namely, the synergistic, additive, neutral, and antagonistic interactions among the inputs. In optimizing the efficiencies of these inputs, researchers should consider their multi-functionality and metabolic complementarity. Despite previous research, the market currently lacks these types of safe and effective products. Hence, further explorations of novel integrated pest management plans that boost synergy and coverage to control multiple pathogens/pests on a single crop are required. Also, setting economic incentives and utilizing a standardized regulation that examines the authentic risks of biopesticides are still called for in order to ease cost-effective formulation, registration, farmer awareness, and usage worldwide. On the other hand, tank mixing that ensures legality and avoids physical and chemical agro-input-based incompatibilities can also provide superior merits. The end in view is the unraveling of the complexities of interactions engaged with in applying multiple inputs to develop soundly formulated, safe, and effective pesticides. Sophisticated techniques should be incorporated to overcome such complexities/limitations. These techniques would engage microencapsulation, nanopesticides, volatile organic compounds as signals for soil inhabitants, bioinformatics, and RNA-Seq in pesticide development.

Poly(butylene adipate-co-terephthalate) (PBAT) is a biodegradable polymer derived from fossil-based raw materials. Combined with poly(lactic acid) (PLA), a major material used in 3D printing, PBAT provides mechanical properties that are particularly attractive for applications requiring flexible 3D-printed objects. However, blends with high PBAT content in fused filament fabrication (FFF) are currently not well-documented, and optimal printing parameters remain unclear for advancing this field. This study aims to address this gap by first exploring the extrusion of filaments at different temperatures, followed by analyzing the printing conditions for PBAT/PLA blends to enhance their spectrum of applications. Using a commercial blend, Ecovio (R) (86 mol% PBAT), this paper demonstrates the feasibility of employing high PBAT content in the additive manufacturing process. Printing parameters such as nozzle temperature and speed were assessed based on the visual quality and mechanical properties of the specimens. The results indicate that extruding at 120 degrees C yields smoother filaments with adequate diameter for FFF applications. Regarding 3D-printing analysis, variations in parameters did not significantly impact elongation at break. However, increasing the nozzle temperature from 180 to 210 degrees C and the printing speed from 50 to 80 mm/s resulted in a 29% increase in tensile strength and a 77% increase in the modulus of elasticity of the 3D-printed specimens which is attributed to better interlayer adhesion. Therefore, high PBAT content blends can improve the performance of 3D-printed materials, and parameters must be optimized to exploit their effectiveness fully across various industrial uses.Highlights Extrusion temperature variations minimally affect PLA/PBAT thermal properties. Higher nozzle temperature and speed significantly improve mechanical properties. Optimal printing conditions for high PBAT blends enable flexible materials. PBAT blends show potential for enhanced 3D printing performance in all sectors.

Enzyme-induced carbonate precipitation (EICP) is an appealing bio-cementation technology for soil improvement in geotechnical engineering. This study investigated the bio-reinforcement efficacy of sword bean crude urease (SWCU)-mediated EICP and the enhancement effect of various additives on it. A set of sand column specimens with different bio-cementation levels were prepared. Magnesium chloride, sucrose, xanthan gum, sisal fiber, calcite seeds, and skim milk powder were adopted for comparison. Bio-reinforcement efficacy was evaluated by mechanical properties. SWCU possessed a similar to 127% higher specific activity than entry-level commercial urease while saving over 2000 times the enzyme cost. All specimens treated with SWCU-mediated EICP presented excellent moldability and uniformity for one-time treatment. UCS increased exponentially with bio-cementation level due to the uniformly growing CaCO3 content and crystal size. UCS of similar to 1.8 MPa was achieved in a single treatment using 60 g/L SWCU and 3.0 M urea-CaCl2. SWCU exhibited a superior bio-reinforcement efficiency over soybean crude urease, commercial urease, and bacterial urease, since higher soil strength was achieved at lower CaCO3 content. Magnesium chloride showed the most significant enhancement effect, implying an extensive application prospect of SWCU-mediated EICP in seawater environments. The absence of wet strength, markedly elevated dry strength, and notably higher stiffness and hardness at low stress (load) phase indicated that xanthan gum would be more suitable for windbreak and sand fixation in arid/semi-arid environments. Sisal fiber could also effectively improve soil mechanical properties; however, the labor and time costs caused by its premixing with soil should be considered additionally in practical applications.

Increases in the frequency and intensity of droughts and heat waves are threatening forests around the world. Climate-driven tree dieback and mortality is associated with devastating ecological and societal consequences, including the loss of carbon sequestration, habitat provisioning, and water filtration services. A spatially finegrained understanding of the site characteristics making forests more susceptible to drought is still lacking. Furthermore, the complexity of drought effects on forests, which can be cumulative and delayed, demands investigation of the most appropriate meteorological indicators. To address this research gap, we investigated the drivers of drought-induced forest damage in a particularly drought-affected region of Central Europe using SHapley Additive exPlanations (SHAP) values, an explainable artificial intelligence (XAI) method which allows for the relevance of predictors to be quantified spatially. To develop a reproducible approach that facilitates transferability to other regions, open-source data was used to characterize the meteorological, vegetation, topographical, and soil drivers of tree vulnerability, representing 41 predictors in total. The forest drought response was characterized as a binary variable (damaged or unchanged) at a 30-m resolution based on the Normalized Difference Moisture Index (NDMI) anomaly (%) between a baseline period (2013-2017) and recent years (2018-2022). We revealed critical tipping points beyond which the forest ecosystem shifted towards a damaged state: <81 % tree cover density, <4% of broadleaf trees, and < 24 m canopy height. Our study provides an enhanced understanding of trees' response to drought, which can support forest managers aiming to make forests more climate-resilient, and serves as a prototype for interpretable early-warning systems.

Excavated soil from widescale tunneling and excavation can be used in 3D-printed constructions. This research investigates the feasibility of 3D printing using geopolymer stabilized excavated soil (GP-E) containing 42% clay rich in kaolinite minerals. At dosages 0.50-1.5 wt%, sucrose is added to control the hydration and timedependent rheological properties, enabling adequate open printing time (OPT) for large-scale printing. Experimental findings show that 1% and 1.5% sucrose addition to GP-E offers OPT of 130 min and 170 min respectively compared to 32 min for GP-E. By enabling better dispersion, the addition of sucrose allows smooth extrusion with shape retention of 90 - 92% at a lower NaOH solution-to-binder ratio (0.68) than GP-E (0.75). Sucrose and clay (in the soil) act synergistically to reduce the time-dependent static yield stress but maintain it at an adequate level of 5-8 kPa required for stacking up the layers without collapse. Flow retention and thixotropy are maintained at 100% during the printing window, which balances extrusion and buildability. As a result, the sucroseGP-E mix could be built up to a height of 1.05 m compared to 0.19 m for GP-E. 1 % sucrose-added GP-E possesses 28 - 40% and 70% higher wet compressive strength and inter-layer bonding respectively compared to GP-E depending on the loading direction. These are linked to the refinement of capillary porosity and a 13-15% reduction in shrinkage. In summary, the findings present a potential route for controlling the printing time of geopolymer-stabilized earthen materials while reducing the embodied carbon and enhancing the mechanical performance.

This study aimed to address the challenges of solid waste utilization, cost reduction, and carbon reduction in the treatment of deep-dredged soil at Xuwei Port in Lianyungang city of China. Past research in this area was limited. Therefore, a curing agent made from powdered shells was used to solidify the dredged soil in situ. We employed laboratory orthogonal tests to investigate the physical and mechanical properties of the powdered shell-based curing agent. Data was collected by conducting experiments to assess the role of powdered shells in the curing process and to determine the optimal ratios of powdered shells to solidified soil for different purposes. The development of strength in solidified soil was studied in both seawater and pure water conditions. The study revealed that the strength of the solidified soil was influenced by the substitution rate of powdered shells and their interaction with cement. Higher cement content had a positive effect on strength. For high-strength solidified soil, the recommended ratio of wet soil: cement: lime: powdered shells were 100:16:4:4, while for low-strength solidified soil, the recommended ratio was 100:5.4:2.4:0.6. Seawater, under appropriate conditions, improved short-term strength by promoting the formation of expansive ettringite minerals that contributed to cementation and precipitation. These findings suggest that the combination of cement and powdered shells is synergistic, positively affecting the strength of solidified soil. The recommended ratios provide practical guidance for achieving desired strength levels while considering factors such as cost and carbon emissions. The role of seawater in enhancing short-term strength through crystal formation is noteworthy and can be advantageous for certain applications. In conclusion, this research demonstrates the potential of using a powdered shell-based curing agent for solidifying dredged soil in an environmentally friendly and cost-effective manner. The recommended ratios for different strength requirements offer valuable insights for practical applications in the field of soil treatment, contributing to sustainable and efficient solutions for soil management.

Propionic acid, benzoic acid, and sorbic acid are common preservatives in processed foods, but their natural concentrations in raw foods are not well understood. In Korea, if propionic acid or benzoic acid exceeds certain levels in processed plant-based foods, manufacturers must prove they are naturally occurring to avoid recalls. This regulation applies to both local and imported products, with non-compliance leading to economic costs and damage to brand reputation. To address this, further research is needed to build a database of naturally occurring preservatives in raw foods and develop food safety standards. This study quantified the levels of propionic, benzoic, and sorbic acids in 37 raw foods stored at different temperatures for 2 weeks, using gas chromatography and high-performance liquid chromatography. The changes in acid concentrations during storage were examined, with preservatives identified by mass spectrometry. Sensory evaluation and total viable count were used to assess spoilage in seafood and meat samples. The matrix effects were evaluated, and the quantification methods were validated using seven food matrices. The intra- and interday accuracies and precisions (% relative standard deviation, %RSD) values met the Codex guidelines. In general, the propionic acid contents of most seafood and meat samples increased during storage, with the highest content being found in manila clams. Interestingly, the fresh sea squirt sample contained a higher propionic acid content (456 mg/kg) than the other samples. However, benzoic acid and sorbic acid were not detected in most samples, with the exception of the jujube and apple samples.