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Carbon quantum dots (CQDs) were synthesized via a one-step solvothermal reaction of citric acid and urea in formamide. The CQDs display excitation-dependent photoluminescence tunable from blue to orange arising from multiple emissive surface states. Time-correlated single-photon counting (TCSPC) reveals triexponential decays with τ₁ = 0.87 ns, τ₂ = 3.25 ns, and τ₃ = 7.0 ns, confirming coexisting fast and slow recombination pathways responsible for multicolor emission. In addition to that femtosecond TAS provides direct insight into core-to-surface relaxation pathways that underpin the broadband emission behavior. In dispersion, the CQDs emit cool-white light with CIE (0.27, 0.32), CCT ≈ 10 411 K, and CRI ≈ 82, while a flexible transparent CQD/PVA film produces white emission with CIE (0.27, 0.33), CCT ≈ 11,346 K, and CRI ≈ 79. A photodiode of configuration FTO/TiO₂/CQDs/MoO₃/Al exhibits wavelength-dependent photocurrent maximum under blue illumination (45 μA at 1 V) with an on/off response of ∼1.2 s correlating optical absorption with electrical behavior. The integration of one-step solvothermal prepared CQDs into both a flexible white-emitting film and a functional photodiode demonstrates their dual optoelectronic applicability.

In this study, the effects of fat content (0.5 and 3.5%), prebiotics (galactooligosaccharides [GOS] and inulin), production method (traditional and commercial), and storage period (21 days at 3 ± 1 °C) on the antimicrobial activity of synbiotic kefirs produced using buffalo milk against certain pathogenic microorganisms (Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans) were determined. Variations in fat content significantly affected antimicrobial activity against E. faecalis (p < 0.01), L. monocytogenes (p < 0.01), and E. coli (p < 0.01); the production method influenced S. aureus (p < 0.01), B. subtilis (p < 0.05), E. faecalis (p < 0.01), E. coli (p < 0.01), and C. albicans (p < 0.01), while prebiotic addition affected S. aureus (p < 0.01), L. monocytogenes (p < 0.05), E. coli (p < 0.05), and C. albicans (p < 0.01). The storage period had a significant effect (p < 0.01) on all examined pathogens, and antimicrobial activity increased as storage time progressed. In general, the use of commercial culture and prebiotics in kefir production enhanced antimicrobial activity. The effects of inulin (on S. aureus, C. albicans) and GOS (on L. monocytogenes, E. coli, C. albicans) varied across microorganisms. Based on the average zone diameters produced by the kefir samples: The highest activity against S. aureus was observed in inulin-containing and cultured samples, against B. subtilis, it was observed on the seventh day in cultured samples, against C. albicans, in inulin-containing and cultured samples (on day 21), against L. monocytogenes, in GOS-enriched and 0.5% fat samples, as well as in inulin-added samples (on day 21), against E. faecalis, in 0.5% fat and cultured samples (on day 21), against E. coli, in 3.5% fat, GOS-added, and cultured samples, and against P. aeruginosa, activity was detected on the seventh and 14^th days of storage.

Novel poly(vinylidene fluoride) (PVDF)/poly(glycidyl methacrylate) (PGMA) blend membranes were successfully fabricated via the nonsolvent-induced phase separation (NIPS) process. Theoretical prediction using the Schneier equation and comprehensive characterization (XRD, FTIR, DSC, FESEM) established that the system exhibits partial miscibility with a critical phase separation threshold around 37 vol % PGMA. Below this threshold, good polymer miscibility was evidenced by favorable thermodynamic parameters and spectroscopic shifts. Beyond it, clear macroscopic phase separation occurred, influencing crystal uniformity and morphology. Crucially, the NIPS process strongly promoted the crystallization of PVDF into the polar, electroactive β-phase. The β-phase content was significantly enhanced from 17% in neat PVDF powder to a maximum of 70% in the optimized blend, despite the overall degree of crystallinity remaining relatively low (26–31%). Moreover, melting the NIPS-formed blends further enhanced the β-phase content at low-to-mid PGMA concentrations. Beyond the crystalline phase modulation, PGMA incorporation effectively modulated the membrane microstructure, significantly enhancing both porosity and surface hydrophilicity. The demonstrated ability to tune the microstructure and polar phase formation through simple blend composition makes these PVDF/PGMA membranes highly promising candidates for advanced functional and biomedical applications.

The optimization of the host materials is one of the methods that could be used to improve the relative sensitivity of luminescent thermometers. Here, we show the host optimization emission of Er³⁺ and Nd³⁺ ions in the YVO₄ phosphors produced by a modified sol–gel route using glucose as a polymerizing agent. X-ray diffraction (XRD) was realized to analyze the formation of the crystalline phase. We found that the emission ratio depends on the size of the YVO₄ particle. Here, we show that YVO₄:Er³⁺,Nd³⁺ phosphors exhibit particle size-dependent relative sensitivity values, varying from 1.32 ± 0.02 to 1.80 ± 0.02% K^–1 at 293 K, and temperature uncertainties below 0.7 K within the physiological range 293–233 K, operating entirely in the first and second biological windows. These sensitivity and temperature uncertainty values were achieved by defining two thermometric parameters as the luminescence intensity ratios, exploiting a combination of emissions from both ion species.

Drill cuttings (DC) are mainly composed of fragmented rocks that are produced during the drilling of oil and natural gas wells. The rocks and minerals present in DC are sources of several chemical elements, including economically valuable elements, such as rare earth elements (REEs). In this paper the sustainability and advantages of the ultrasound-assisted extraction were applied for the extraction and recovery of REEs from DC. To determine the optimal extraction conditions, a full factorial and Doehlert matrix design was employed. The DC were characterized by XRD and EDXRF, and the REEs concentrations were determined by ICP-MS. The REEs recovery was performed by precipitation with oxalic acid. The analyzed DC samples were primarily composed of aluminosilicate minerals, the α-quartz, calcite, albite, and muscovite being the most common phases. The EDXRF analysis confirms the predominance of silicate and aluminosilicate rock-forming minerals and accounts for the significant content of Fe, Ca, Na, and Mg. The optimal extraction condition was achieved using HNO₃ at 7.0 mol L^–1 as extractor and ultrasound-assisted extraction at 80 °C for 60 min. The efficiency of extraction in the DC analyzed was high (for La and Ce, >82%), and after precipitation, good recoveries were achieved, especially for La and Ce (>90%). Thus, the proposed ultrasound-assisted extraction process proved to be suitable for the recovery of these elements from DC, contributing to sustainable development and the circular economy.

Receptor tyrosine kinases (RTKs), including VEGFR-2, EGFR, and c-MET, have been recognized as promising oncogenic targets in tumor progression, invasion, and metastasis. Developing multitarget inhibitors that block these kinases simultaneously offers a powerful strategy to suppress angiogenesis and oncogenic signaling, while potentially minimizing adverse effects. A new series of benzothiazole- and benzimidazole-based urea derivatives was designed rationally through scaffold modification and linker optimization to enhance multikinase inhibition. Moreover, in vitro evaluation of the newly synthesized series revealed that compounds 6a–c, 7a, 12a, 17, and 18 exhibited multitarget inhibitory potential. Additionally, 11b, 12a, 17, and 18 showed the best antiproliferative potential against MCF7 and A549 cells, as indicated by the antiproliferative assay. While compounds 6b, 7a, 17, and 18 demonstrated negligible cytotoxicity against normal HEK-293 cells, with IC₅₀ values exceeding 100 μM (>100 μM). Furthermore, the antiangiogenic efficacy of 11b, 12a, 17, and 18 was validated through CAM assays, which markedly suppressed neovascularization. Molecular docking revealed efficient occupation of 6b, 7a, 12a, 17, and 18 with key binding pockets across VEGFR-2, EGFR, and c-Met. The 200 ns molecular dynamics (MD) simulations confirmed the stability of the 4ASD–6b complex with enhanced flexibility compared to sorafenib. Collectively, these findings establish benzothiazole, benzimidazole, and quinoline-based urea hybrids as promising leads with enhanced multikinase selectivity and reduced toxicity compared to existing inhibitors, offering strong therapeutic potential in angiogenesis-driven cancers.

Pineapple processing generates considerable waste with byproducts (peels, cores, crowns, and leaves) often containing high levels of bromelain, a proteolytic enzyme with promising applications in animal feed. However, the instability and low activity of crude bromelain (CBr) in aqueous form limit its industrial utilization. In this study, CBr was extracted from pineapple peel waste and directly immobilized onto a bentonite (Bt)–carboxymethylcellulose (CMC) composite without further purification. The CBr–Bt–CMC composites were prepared via ionotropic gelation, with cysteine incorporated to enhance enzymatic performance. The composite with a bromelain-to-cysteine mass ratio of 1:65 could enhance catalytic activity by over 1,000% compared to the control without cysteine. It exhibited an immobilization yield exceeding 80% with significantly improved thermal stability, retaining nearly twice the activity of free CBr after 10 min at 100 °C. Application of the immobilized CBr in soybean meal (SBM) hydrolysis demonstrated significant improvements in nutritional value (approximately 3-fold), degradation of allergenic proteins, and generation of low-molecular-weight peptides at 60–70 °C within 30 min. Immobilized CBr exhibited sustained catalytic performance, retaining over 60% of its initial activity after four cycles. Collectively, these results highlight the potential of the immobilized crude bromelain as a robust and efficient biocatalyst for the enhancement of nutritional value in feed protein.

This study explores the enhancement of silicone-based fouling release coatings through the incorporation of graphene oxide and silver nanoparticles. Laboratory tests demonstrated significantly improved microfouling resistance with increasing nanoparticle concentrations while maintaining surface energies within the optimal range for fouling release. During a 7 month marine field immersion trial, only the silver nanoparticle-containing composite coating exhibited improved antifouling efficacy over time, while the performance of the graphene oxide-containing composite coating was comparable to the simplified nonbiocidal fouling release coating. Both composite coatings showed a slightly earlier onset of macrofouling. Microscopy revealed notable nanoparticle agglomeration and localized algal attachment, emphasizing the need for improved dispersion and surface integration. Though the addition of nanoparticles for boosting antifouling efficacy with both biocidal and fouling release strategies showed only marginal improvements, clear evidence of enhanced performance is seen. Advancing this technology demands targeted control over nanoparticle distribution and leaching, which are key challenges that must be addressed to unlock the full potential of next-generation, sustainable antifouling coatings.

The Schiff base derived from the condensation of 4-aminosalicylic acid with 2,3-dihydroxybenzaldehyde was synthesized and characterized by using experimental techniques, theoretical calculations, and in silico methods. Single-crystal X-ray diffraction analysis showed that the compound crystallizes in the triclinic P1̅ space group with two molecules in the asymmetric unit, both adopting a zwitterionic keto form. In silico studies predict high gastrointestinal absorption, low toxicity, and potential activity as a transthyretin (TTR) inhibitor, with binding affinity comparable to that of the drug Tolcapone, suggesting that the synthesized compound may be a promising scaffold for a TTR stabilizer.

Rheumatoid arthritis (RA) is a common chronic immune-mediated inflammatory disease. Current treatment strategies for RA are limited and often associated with significant adverse effects. Methotrexate (MTX), a first-line therapeutic agent for RA, demonstrates efficacy; however, its adverse effects remain a concern, particularly its tendency to increase reactive oxygen species (ROS) levels and exacerbate oxidative stress. In this study, we developed an MTX/CD complex by combining MTX with bamboo leaf-derived carbon dots (CDs). Experimental results showed that the MTX/CD complex effectively reduced ROS generation and significantly mitigated oxidative stress, while retaining the favorable therapeutic effect of MTX against RA. Moreover, the composite more effectively suppressed the abnormal proliferation of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS), thereby alleviating joint symptoms in RA patients and offering a novel therapeutic strategy for RA management.