Search Results (2,706)

Water scarcity is a major constraint to sustainable horticultural production, particularly in arid and semi-arid regions. This study evaluated the effectiveness of two natural foliar biostimulants, chitosan and Spirulina extract, in improving water productivity, growth performance, biomass production, and drought tolerance of passion fruit (Passiflora edulis Sims) seedlings under deficit irrigation. A factorial experiment was conducted using three irrigation regimes (100%, 85%, and 70% of field capacity, FC) combined with three foliar spray treatments: distilled water (control), chitosan (1 g L⁻¹), and Spirulina extract (1 g L⁻¹). Deficit irrigation significantly reduced chlorophyll content, vegetative growth, biomass production, and water productivity, with the greatest reductions observed at 70% FC. Foliar application of both biostimulants effectively alleviated these adverse effects by enhancing plant growth, biomass production, chlorophyll retention, and water productivity under water-limited conditions. Chitosan consistently outperformed Spirulina, particularly under moderate water deficit, by reducing irrigation water requirements while maintaining seedling growth and physiological performance comparable to those under full irrigation. Multivariate analyses, including Pearson correlation, principal component analysis, and response surface methodology, revealed strong positive relationships among biomass production, chlorophyll content, vegetative growth traits, and water productivity. Among all treatments, foliar application of chitosan at 1 g L⁻¹ combined with 85% FC was identified as the optimum strategy, providing substantial irrigation water savings while maintaining vigorous seedling growth, high biomass production, and superior water productivity. These findings demonstrate that integrating moderate deficit irrigation with chitosan application is an effective and sustainable strategy for improving passion fruit nursery production under conditions of limited water availability. Full article

This study evaluated the effect of sports and energy drinks on the surface roughness of three commonly used restorative dental materials: resin-based composites (RBCs), resin-modified glass ionomer cements (RMGICs), and conventional glass ionomer cements (GICs). Sixty-three A2-shade specimens of each material were fabricated, stored in distilled water for 24 h, and then immersed in six commercially available beverages or distilled water (control) for 6, 30, or 60 h. Surface roughness was assessed after each immersion period using contact profilometry, and the effects of material type, immersion medium, and exposure time were compared. Surface roughness increased with longer immersion times for all materials, although the magnitude of change varied significantly among material types. RBCs showed the greatest resistance to surface degradation, whereas RMGICs and particularly GICs exhibited progressively higher roughness values over time. Beverages generally produced greater surface roughness than distilled water, with sugar-containing formulations showing higher roughness values than their sugar-free counterparts. Prolonged exposure to sports and energy drinks may adversely affect the surface integrity of restorative materials. Resin-based composites demonstrated the highest resistance to roughness changes, whereas glass ionomer cements were the most susceptible. Increased surface roughness may contribute to plaque accumulation, staining, and material wear, potentially compromising the long-term clinical performance of restorations. Full article

The ongoing development of subtractive options for indirect restorations places clinicians in a position that requires adaptation, understanding and choosing of the most suitable option for the long-term survival of the restoration. Mechanical parameters represent important indicators of long-term success. Consequently, this research aimed to assess the impact of water sorption on the mechanical properties of two direct resin composites, Gradia Direct Anterior A2 and Filtek Z550 A2 and three CAD/CAM subtractively manufactured dental resin composites, Vita Enamic, Brilliant and Cerasmart. A total of one hundred specimens (50 control, 50 underwent this protocol: dehydration, immersion in distilled water for 30 days and then re-desiccation), standardized to the dimensions of 14 mm × 4 mm × 1.2 mm were subjected to three-point bending test (based on ISO 4049:2019 and ISO 6872:2015), in order to find out the flexural strength and the elastic modulus of the material at the breaking point. Then, the fractured sample surfaces were fractographical analyzed. Using the two-parameter Weibull approach, the Weibull modulus (m) and the characteristic strength (σ₀) were evaluated. In this investigation, the elastic modulus varied from 5.8 (Gradia Control) to 20.31 (Vita Degraded) GPa, with the upper limit close to the values of natural dentin (17.7–29.8 GPa). The values of flexural strength ranged from 174.47 (Brilliant Control) to 79.2 (Gradia Control), subtractively processed materials demonstrating higher flexural strength and elastic modulus values than the direct resin composites, which is related to their high inorganic filler content. All material groups, except for Gradia Control, had a flexural strength more than the 80 MPa minimum value needed to sustain masticatory force. The dehydration and hydration cycles did not have a statistically significant influence on the mechanical properties of the material. The fractographic analysis revealed fracture patterns and features associated with the microstructure, with the PICN category material being particularly notable. Weibull analysis revealed that the direct resin composite materials exhibited higher reliability, lower data scatter and CAD-CAM materials showed greater characteristic strength, with a notably high performance of the nano-hybrid direct resin composite. Full article

Winery residues generated by the wine industry represent an important sustainability challenge but also a valuable resource for producing vermicompost-derived products with potential agricultural applications through vermicomposting. This study evaluated the effects of aqueous vermicompost extracts produced from winery residues on the early in vitro development and physiological performance of garden cress (Lepidium sativum L.) and cucumber (Cucumis sativus L.) seedlings. Seedlings were cultivated on peat-based pellets (Jiffy-7^®) under controlled conditions and treated with two extract concentrations (10% and 20%, w/v) or distilled water (control). After 30 days, morphological traits (shoot height, leaf number and biomass) and biochemical parameters (photosynthetic pigments and total phenolics) were assessed. Both species showed high survival rates (>85%) and no phytotoxic symptoms. Compared with the control, VE20% increased chlorophyll a, chlorophyll b, and total chlorophyll contents in garden cress by 40.3%, 35.9%, and 38.9%, respectively, whereas VE10% increased chlorophyll a, total chlorophyll, and carotenoid contents in cucumber by 15.7%, 11.5%, and 25.0%, respectively. Total phenolic content did not differ significantly among treatments in either species (p > 0.05). These findings indicate that vermicompost extracts produced from winery residues exhibited low phytotoxic potential under the experimental conditions tested and influenced photosynthetic pigment accumulation without adversely affecting seedling growth. These responses warrant further investigation under ex vitro and field conditions to determine whether the observed physiological changes translate into relevant agronomic effects. Full article

Objectives: This study investigated the effects of oat β-glucan on liver injury and the gut microbiota in a rat model of a high-fat diet combined with streptozotocin (STZ)-induced type 2 diabetes. Methods: To achieve this, specific-pathogen-free (SPF) male Sprague-Dawley (SD) rats were utilized and initially acclimated to the laboratory environment for one week. Following the stabilization period, 12 rats were randomly selected as the normal control (CON) group and fed a standard chow diet, while the remaining rats were fed a high-fat diet for 4 weeks and then were induced via intraperitoneal (i.p.) injection of multiple low doses of STZ (30 mg/kg) in freshly prepared sodium citrate–citric acid buffer (pH 4.5) once a week for two consecutive weeks. Blood glucose levels were measured using a glucometer, and rats with fasting blood glucose levels exceeding 11.1 mmol/L for 7 consecutive days were confirmed as diabetic. Subsequently, 48 confirmed diabetic rats were then randomly divided into four subgroups (n = 12 each): the diabetic model (DM) group, Oat β-Glucan Low-Dose (OGL) group, Oat β-Glucan Middle-Dose (OGM) group, and Oat β-Glucan High-Dose (OGH) group. The rats in the OGL, OGM, and OGH groups were gavaged with oat β-glucan at doses of 0.275 g/kg BW, 0.55 g/kg BW, and 1.10 g/kg BW, respectively, daily for 10 weeks, while the CON and DM groups received an equivalent volume of distilled water. Results: Following the 10-week intervention, the rats were sacrificed for multi-indicator assessments. Oat β-glucan treatment significantly improved hyperglycemia and alleviated hepatic injury. Histological analysis confirmed that oat β-glucan alleviated pathological liver damage. Furthermore, oat β-glucan effectively reshaped the gut microbiota by reducing the abundance of Enterococcaceae and increasing the abundance of beneficial taxa, including Ruminococcaceae, Lachnospiraceae, and Christensenellaceae. Compared with the DM group, the OGH group exhibited a significant reduction in metabolic endotoxemia (serum LPS). Meanwhile, the observed microbial shifts were closely correlated with the downregulation of pro-inflammatory cytokines (TNF-α and IL-6). Conclusions: In conclusion, our findings demonstrate that oat β-glucan exerts a protective effect against diabetic liver injury by modulating gut microbiota composition and suppressing inflammation via the gut–liver axis, highlighting its potential as a functional dietary strategy for diabetes management. Full article

In this study, porous polyvinylidene fluoride (PVDF) hollow fiber (HF) membranes for membrane distillation applications were successfully prepared using TamiSolve^® NxG, an innovative lower-hazard solvent, through the non-solvent induced phase inversion technique. The influence of the bore fluid composition and bore fluid flow rate on membrane morphology and performance was systematically investigated while maintaining a fixed polymer dope formulation. The prepared hollow fibers were thoroughly characterized in terms of morphology, membrane thickness, porosity, contact angle, mechanical resistance, pore size, and pure water permeability. In addition, their performance was investigated through Direct Contact Membrane Distillation (DCMD) tests in order to evaluate their applicability in desalination processes. The developed PVDF HF membranes exhibited pore sizes comparable to those of commercial polypropylene (PP) membranes and achieved high permeate flux together with excellent salt rejection, demonstrating their promising potential for sustainable membrane distillation and desalination applications. Full article

This study presents the development and evaluation of a hydrogel-based superabsorbent polymer sensor (HSPS) for measuring soil suction and establishing the soil–water characteristic curve (SWCC) of unsaturated soils. Polyacrylamide (PAM) hydrogels were synthesized via UV-induced free radical polymerization using acrylamide with varying crosslinking degrees. The polymers were characterized through FT-IR and TGA analyses, confirming successful synthesis and high thermal stability. Swelling, water retention, and kinetic behavior were systematically investigated. Results indicated that lower crosslinking density significantly enhanced swelling capacity, reaching up to 3000% in distilled water, while saline environments reduced absorption due to ionic screening effects. Swelling kinetics followed anomalous (non-Fickian) diffusion behavior and were well described by the pseudo-second-order Schott model. The synthesized polymers were integrated into a modified high-sensitivity pressure sensor operating on the osmotic principle to measure matric suction. The system was validated using natural soil. Among the tested formulations, the HSPS-3 demonstrated the most reliable suction measurements, reaching values up to approximately 1 MPa without significant temperature sensitivity. The resulting SWCC exhibited bimodal characteristics consistent with the soil’s dual pore structure. The proposed method provides a cost-effective, simple, and efficient alternative for suction measurement, expanding the practical range of SWCC determination in unsaturated soil mechanics. Full article

Underwater object detection is a fundamental task in underwater sensing and is generally approached using either optical or sonar sensors. Although optical imaging provides rich semantic information, it is highly susceptible to water turbidity and illumination variations. By contrast, sonar imaging can effectively overcome visibility limitations, yet it suffers from severe speckle noise and blurred object contours. Moreover, resource-limited platforms impose strict demands on model lightweightness and real-time performance. To this end, this paper proposes a novel cross-modal heterogeneous distillation method (CMHD) to balance detection accuracy and computational complexity. CMHD performs cross-modal knowledge transfer by leveraging the rich semantics of RGB images to enhance sonar feature representation, compensating for the information deficiency of the sonar modality. Meanwhile, a heterogeneous distillation scheme compresses the detection capability of a high-capacity teacher YOLOX-M into a lightweight student YOLOX-S-Ghost, enabling strong feature extraction under a highly compact model. To mitigate the modality gap and geometric inconsistency between RGB and sonar modalities, we design a branch-aware heterogeneous distillation strategy. To improve detection accuracy and reduce model parameters, the student network incorporates Coordinate Attention (CA) in its backbone and adopts a lightweight neck design. Experiments on the UXO^† dataset demonstrate that CMHD achieves 79.6% mAP and 82.6% mAR, significantly outperforming the compared representative methods and serving as an accurate, efficient, and lightweight solution for underwater sonar object detection. Full article

Natural coagulants have emerged as potential alternatives to synthetic chemicals in water treatment, especially for decentralized and low-resource applications. However, many previously reported Aloe vera-based coagulant preparation methods rely on drying, powder production, distilled water extraction, refrigeration, or other laboratory-dependent procedures that increase operational complexity and limit practical implementation. This study presents a simplified and rapid protocol for producing an Aloe vera-based natural coagulant using accessible materials and simplified preparation steps. The proposed methodology consists of extracting Aloe vera g13el, homogenizing 2 g of fresh gel with 50 mL of tap water using a household blender, and applying simple paper filtration to obtain the liquid coagulant. The protocol can be completed in less than 10 min without specialized laboratory infrastructure, energy-intensive processing, or laboratory-grade reagents. Coagulation performance was evaluated using synthetic turbid water with initial turbidity levels of 100, 200, and 300 NTU. Significant turbidity reduction was observed under all tested conditions, with several samples reaching residual turbidity values close to or equal to 0 NTU after 50–60 min of sedimentation. The results demonstrate the potential of the proposed protocol as a rapid, reproducible, and accessible approach for future investigation in point-of-use and decentralized water treatment applications. Full article

The use of non-conventional systems for domestic wastewater management has gained attention in rural areas of the Global South, where centralised infrastructure is often limited. This study presents the design, construction, and pilot-scale evaluation of a solar still unit operated under passive and photovoltaic-assisted active modes as a separation and polishing component for domestic wastewater from a rural site in Barrancabermeja, Colombia. Performance was assessed through physicochemical and microbiological characterisation of influent wastewater and treated condensate, together with hourly monitoring of distillate production, water temperature, glass-cover temperature, and ambient conditions. Under passive operation, a theoretical distillation model was applied, empirically adjusted, and evaluated using MAE, RMSE, MAPE, and R². Under the tested conditions, indicative within-mode reductions reached 80.9% and 89.3% for chemical oxygen demand (COD), 95.6% and 93.8% for biochemical oxygen demand (BOD₅), and 94.0% and 94.4% for total suspended solids (TSS) under passive and active modes, respectively. Microbial indicators showed minimum estimated reductions above 99.9%, with faecal coliforms reduced to very low levels in passive mode and not detected in the analysed active-mode condensate sample. Maximum daily condensate production reached 1.445 L m⁻² day⁻¹ in passive mode and 2.262 L m⁻² day⁻¹ in active mode, confirming the low-flow nature of the unit. Approximately 50% of daily production occurred between 12:00 and 15:00 h. The model reproduced the main diurnal production pattern, although empirical correction was required. Overall, the unit may improve condensate quality under pilot-scale conditions and shows potential as a polishing component within decentralised, low-flow treatment trains. Full article

Pure ZnO and ZnO/Gd₂O₃ (1 and 2 mol %) nanoneedles were synthesized via a sonochemical route and evaluated as catalytic materials for the degradation of paracetamol using glass and PTFE (Teflon) stirring rods. The morphology and elemental composition of the obtained nanostructures were investigated by SEM and EDS analyses, confirming the formation of anisotropic rod-like architectures and the successful incorporation of gadolinium species into the ZnO matrix. The optical and defect-related properties were further examined by photoluminescence and UV–Vis spectroscopy, revealing defect-related modifications in the electronic structure and improved charge carrier behavior in the gadolinium-modified samples. Comparative catalytic experiments showed higher degradation efficiencies in the system employing the glass stirring bar compared to the PTFE. However, the differences between these two setups are not limited solely to the stirring bar material, but also involve variations in interfacial contact conditions during operation. Therefore, the observed differences in catalytic activity cannot be attributed to a single mechanistic origin such as mechanically induced effects, but rather reflect the combined influence of catalyst–surface interactions and the specific nature of the stirring medium. The influence of inorganic ions on paracetamol degradation was also investigated using distilled water and aqueous solutions containing sodium chloride, sodium sulfate, and sodium hydrogen carbonate. In both systems, the ZnO/Gd₂O₃ samples exhibited higher degradation efficiency than pristine ZnO, indicating that Gd incorporation plays a key role in enhancing catalytic performance. This improvement can be associated with a modified defect structure and more favorable charge carrier dynamics in the doped material. The mineralization efficiency of the treated solutions was additionally evaluated through chemical oxygen demand (COD) measurements, confirming a significant reduction in organic load after treatment. Full article

This study investigated the use of microwave (MW) to enhance the performance of a granular thermo-plasma expanded graphite (GTPEG) to remove an organic cationic dye, methylene blue (MB), from freshwater, taking the benefits of MW-assisted regeneration. Expanded graphite (EG), low-density and mesoporous, has been proposed previously as a means of extracting organic compounds from water due to its hydrophobicity and weak polarity. We granularized EG to facilitate its subsequent regeneration and reuse and separation, and MW was used to improve the adsorption of EG. The most important factors affecting adsorption were determined using response surface methodology, along with 3-D graphics illustrating the relationship between several variables. The experimental results show that 94% of MB adsorbed onto MW-GTPEG in deionized distilled water within 20 min. Additionally, adsorbent regeneration using MW did not affect the adsorption capacity and rate after 10 cycles albeit with a small weight loss of <8%. From our results, we believe that the main factor affecting the adsorption was the physical characteristics of the adsorbent, with other minor factors such as the adsorbent dose and initial concentration. Our findings suggest that MW irradiation may be a promising alternative for enhancing and regenerating GTPEG. Full article

Microalgal lipid extraction, particularly the subsequent solvent recovery phase, constitutes the primary energy bottleneck in algal-based biodiesel biorefineries. Recently, switchable polarity solvents (SPS), such as the tertiary amine N,N-dimethylcyclohexylamine (DMCHA), have emerged as promising ‘green’ alternatives capable of extracting lipids directly from wet biomass, theoretically bypassing energy-intensive drying and solvent recovery distillation stages. This study presents a rigorous techno-energetic and thermodynamic evaluation combined with supporting experiments for qualitative conclusions to scrutinize the actual viability of DMCHA-mediated extraction against conventional hexane benchmarks, across three process configurations using different biomass types: algal liquor, wet paste, and dried biomass. Contrary to widespread assumptions in the literature, fundamental thermodynamic calculations reveal that the energy required for amine regeneration via protonation/deprotonation mechanisms equals or exceeds that of conventional distillation. Furthermore, mitigating biomass drying inadvertently escalates overall downstream energy and economic penalties due to the excessive solvent volumes demanded by dilute aqueous matrices. Direct extraction from algal liquor displays a cost and energy consumption countably higher than the other scenario; precisely, a cost of 232 €/kg of lipids and energy consumption of 454 kWh/kg of lipids. Extraction from wet paste exhibits, indeed, a slightly lower energy consumption compared to the hexane process (respectively 51 kWh/h versus 72 kWh/kg), but, due to the CO₂ requirements, the cost is double (19 €/kg of lipids versus 8 €/kg of lipids). Ultimately, while switchable polarity chemistry offers a marginal reduction in process water footprints, it introduces substantial operational complexity, elevated carbon dioxide payloads, and severe solvent degradation risks, challenging its current readiness for industrial upscaling. Full article

Introduction: Oil pulling therapy has gained increasing attention as a natural oral hygiene practice; however, evidence regarding its clinical effectiveness remains limited and inconclusive. This study aimed to evaluate the effects of oil pulling therapy on dental plaque regrowth and tooth discoloration compared with chlorhexidine. Materials and Methods: One hundred systemically healthy dental students were randomly allocated to five groups: chlorhexidine, coconut oil, black cumin seed oil, terebinth oil, and distilled water. Following professional prophylaxis, participants refrained from mechanical oral hygiene for four days and used their assigned intervention twice daily. Plaque accumulation was assessed using the Turesky modification of the Quigley–Hein Plaque Index, gingival inflammation using the Gingival Index, and tooth color using CIELAB color difference measurements. Data were analyzed using one-way ANOVA or Kruskal–Wallis test with appropriate post hoc tests, depending on the distribution of data. Results: Plaque scores differed significantly among groups (p < 0.001), with chlorhexidine showing superior plaque inhibition compared with all oil-based interventions and distilled water. Gingival index values were lowest in the chlorhexidine group, although differences among oil groups were not statistically significant. Tooth discoloration was significantly greater with chlorhexidine than with all oil-based interventions (p < 0.001). Conclusions: Oil pulling therapies demonstrated lower anti-plaque efficacy than chlorhexidine but resulted in less tooth discoloration. These findings suggest that oil pulling may serve as an adjunct rather than an alternative to conventional plaque control. Full article

Hydrogen peroxide (H₂O₂) is widely used in semiconductor cleaning and etching, where ultralow levels of metallic, anionic, organic, and particulate impurities must be strictly controlled. Industrially produced H₂O₂ therefore requires extensive downstream purification before it can meet electronic-grade specifications. Conventional purification routes based on distillation or rectification, adsorption, ion exchange, and final filtration are technically mature, but they remain constrained by substantial energy consumption, multiple treatment stages, chemical regeneration, secondary waste generation, and safety risks associated with H₂O₂ decomposition. This review critically evaluates membrane technologies for purifying and concentrating electronic-grade H₂O₂. Microfiltration and ultrafiltration are discussed as front-end clarification processes, nanofiltration as an intermediate impurity-load-reduction step, and reverse osmosis as the membrane process with the strongest direct experimental for ionic-impurity removal from concentrated H₂O₂. Pervaporation and membrane distillation are assessed as emerging water-removal technologies, although their industrial applicability remains insufficiently validated. Membrane material strategies, including oxidation-resistant polymers, inorganic and hybrid membranes, antioxidant-containing composites, and emerging MOF- and two-dimensional-material-based membranes, are also evaluated. Particular attention is paid to the limited direct evidence available for emerging materials and to the risks of H₂O₂ decomposition, material leaching, particle release, and deterioration of membrane selectivity. The available evidence indicates that membrane processes are currently more appropriately regarded as complementary clarification, purification, polishing, or concentration units rather than complete replacements for established industrial technologies. Future studies should prioritize long-term oxidative stability, ppb- and ppt-level impurity validation, low H₂O₂ loss, module-material compatibility, process safety, and continuous pilot-scale techno-economic assessment. Full article