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Pathogen-induced infections and the rise of antibiotic-resistant bacteria, such as Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), pose significant global health challenges, emphasizing the need for new antimicrobial strategies. In this study, we synthesized graphene oxide (GO)-based composites functionalized with silver nanoparticles (AgNPs) and copper nanoparticles (CuNPs) as potential alternatives to traditional antibiotics. The objective is to assess the antibacterial properties of these composites and explore their efficacy against E. coli and S. aureus, two common bacterial pathogens. The composites are prepared using eco-friendly and conventional methods to ensure effective nanoparticle attachment to the GO surface. Structural and morphological characteristics are confirmed through SEM, AFM, EDS, XRD, UV-vis, FTIR, and Raman spectroscopy. The antibacterial efficacy of the composites is tested through disk diffusion assays, colony-forming unit (CFU) counts, and turbidimetry analysis, with an emphasis on understanding the effects of different nanoparticle concentrations. The results demonstrated a dose-dependent antibacterial effect, with GO/AgNP-1 showing superior antibacterial activity over GO/AgNP-2, particularly at lower concentrations (32.0 μg/mL and 62.5 μg/mL). The GO/CuNP composite also exhibited significant antibacterial properties, with optimal performance at 62.5 μg/mL for both bacterial strains. Turbidimetry analysis confirmed the inhibition of bacterial growth, especially at moderate concentrations, although slight nanoparticle aggregation at higher doses reduced efficacy. Lastly, both GO/AgNP and GO/CuNP composites demonstrated significant antibacterial potential. The results emphasize the need to fine-tune nanoparticle concentration and refine synthesis techniques to improve their efficacy, positioning these composites as strong contenders for antimicrobial use. [ABSTRACT FROM AUTHOR]

The Mediterranean Diet (MD) is characterized by a high intake of fruits and vegetables (FVs), which is considered as an important contributor to the beneficial effects of the MD pattern. In this cross-sectional study, we compared the food choices, evaluated by dietary habit questionnaires, of a sample of 995 adults, including 601 and 394 participants from Southern Italy and the Dominican Republic, respectively. In addition, we focused on their FV consumption, assessed by the Mediterranean Diet Adherence Screener (MEDAS) questionnaire, and on its association with skin carotenoid levels as measured by the Veggie Meter®. We found that a significantly higher percentage of Italians had five meals/day and breakfast compared to Dominicans (five meals/day: 43 vs. 25, p < 0.05; breakfast: 89 vs. 79, p < 0.05), whereas a lower percentage of participants from Italy consumed snacks between the two meals compared to the Dominican Republic population (47 vs. 70, p < 0.005). Most of the participants from both populations had breakfast at home. However, 59.3% of Italians and 27.5% of Dominicans (p = 0.005) had breakfast between 7:00 and 9:00 a.m., whereas 5.8% and 27.5% (p = 0.001) had breakfast after 9:00 a.m., respectively. Milk/yogurt and eggs were the most consumed foods for breakfast in Italy and the Dominican Republic, respectively. Regarding the main meals, most of the Italians and Dominicans had a first course for lunch and a second course for dinner. Of note, we observed that approximately half of the Italians ate FVs in their main meals and had a higher carotenoid score than the Dominicans. Interestingly, in the multiple linear regression analysis, we found that the carotenoid score was positively associated with sex (β = 0.078; p = 0.009), age (β = 0.008; p = 0.001), vegetable consumption (β = 0.12; p = 0.041) and the perception of a healthy diet (β = 0.12; p = 0.001) in the Dominic Republic population, while the carotenoid score was directly associated with sex (β = 54.97; p < 0.0001) and both vegetable (β = 25.42; p = 0.0008) and fruit (β = 38.61; p < 0.0001) consumption in the Italian sample. Our findings confirm the need to promote nutrition-based interventions to encourage FV intake, particularly in non-Mediterranean countries. [ABSTRACT FROM AUTHOR]

Herein, we introduce a simple precipitation method for preparing graphene oxide–silver nanoparticle (GO/AgNP) composites, utilizing Calendula officinalis (C. officinalis) seed extract as both a reducing and stabilizing agent. Our research combines the sustainable preparation of graphene oxide (GO) with the green synthesis of silver nanoparticles (AgNPs), aiming to explore the potential of the obtained composite as a novel antibacterial material. To establish a benchmark, the synthesis was also performed using sodium citrate, a conventional reducing agent. The resultant GO/AgNP composites were characterized through several analytical techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDS), Raman spectroscopy, X-ray diffraction (XRD), infrared (IR) spectroscopy, and ultraviolet–visible (UV-vis) spectroscopy, confirming the successful functionalization of GO with AgNPs. The antibacterial effectiveness of the composites was systematically assessed against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with nanoparticle concentrations spanning from 0 to 250 µg/mL, utilizing mostly disk diffusion and colony-forming unit (CFU) count assays. The AgNPs were characterized by a size range of 15–50 nm. Notably, the GO/AgNP composite prepared using C. officinalis seed extract demonstrated superior antibacterial activity at all tested concentrations, outperforming both pure GO and the GO/AgNP composite prepared with sodium citrate. The most pronounced antibacterial effect was observed at a concentration of 32.0 µg/mL. Therefore, this innovative synthesis approach may offer a valuable contribution to the development of new therapeutic agents to combat bacterial infections, suggesting further exploration into antibacterial coatings or potential drug development. [ABSTRACT FROM AUTHOR]

The evolution of electric double-layer capacitors (EDLCs) has significantly benefited from advancements in graphene-based materials, particularly graphene oxide (GO) and reduced graphene oxide (rGO). This systematic review consolidates and analyzes existing research on the roles of GO and rGO in enhancing the performance of EDLCs, focusing on synthesis methods, electrode fabrication, electrolytes, and performance metrics such as capacitance, energy density, and cycling stability. Following the PICOS and PRISMA frameworks, a comprehensive literature search was conducted across Scopus, Web of Science, PubMed, and IEEE Xplore, covering the period from 2010 to 2023. A total of 128 articles were initially identified, with 27 studies meeting the inclusion criteria after rigorous screening and full-text analysis. Key findings reveal that the incorporation of GO and rGO in EDLCs leads to significant improvements in specific capacitance, energy density, and cycling stability. Notable advancements include novel synthesis techniques and composite materials such as nitrogen-doped graphene, graphene/polyaniline hybrids, and various metal oxide–graphene composites, which exhibit superior electrochemical performance. However, challenges such as material scalability, environmental sustainability, and consistency in synthesis methods remain. This review stresses the great potential of GO and rGO in the development of high-performance EDLCs and highlights the need for continued research to address existing challenges and further optimize material properties and fabrication techniques. [ABSTRACT FROM AUTHOR]

Cruz Salazar, Y.M.; Upia de la Rosa, N.; Ramírez Martínez, W.R.; Caputi, L., and Arias Polanco, M., 2024. Physicochemical characterization of beach sands from renowned tourist regions of the Dominican Republic. Journal of Coastal Research, 40(1), 150–166. Charlotte (North Carolina), ISSN 0749-0208. The Dominican Republic's beautiful beaches drive its economy through tourism. Beach sands from tourist regions around the island were analyzed to characterize their physicochemical properties. The beaches of El Morro in Monte Cristi, Dorada in Puerto Plata, El Portillo in Samaná, Bibijagua in La Altagracia, Isla Saona in La Romana, Guayacanes in San Pedro de Macorís, Punta Salinas in Peravia, and Bahía de las Águilas in Pedernales were studied. The particle sizes of the studied beaches were found to vary from coarse (600–850 µm) to fine sands (75–211 µm), with medium sands (212–599 µm) being the most common. Scanning electron microscopy (SEM) analysis revealed morphologies dominated by lithoclasts at Punta Salinas, while coral reef fragments and marine skeletons (bioclasts) were prevalent at the other beaches. The major minerals identified through X-ray diffraction (XRD) were Mg-calcite, Mg-Fe-calcite, quartz, and aragonite. Aragonite predominated on the beaches along the Caribbean coast, while calcite was more prevalent on the Atlantic coast. Bahía de las Águilas was the only beach with sand composed almost entirely of aragonite, which harbored diatom algae in its pores. Energy-dispersive X-ray (EDX) microanalysis detected Ca, Mg, and O on the surface of all samples, indicating that carbonate minerals dominated the sand composition. No toxic heavy metals were detected. Thermal decomposition occurred at temperatures ranging 453–822 °C, with total mass loss ranging from 1.9% to 42% for all locations. Additionally, Fourier transform infrared spectroscopy (FTIR) identified vibrations of C-O bonds of calcite and aragonite. The most prominent vibrations of aragonite and calcite were found between 830 and 900 cm–1, where their peak relative intensities served as a qualitative marker. These findings offer valuable insights into the physicochemical characteristics of beach sands in the country, which can contribute to the development of sustainable tourism practices and effective coastal management. [ABSTRACT FROM AUTHOR]

The development of efficient energy storage systems is critical in the transition towards sustainable energy solutions. In this context, the present work investigates the viability of using orange juice, as a promising and sustainable precursor, for the synthesis of activated carbon electrodes for supercapacitor technologies. Through the carbonization-activation process and controlling the preparation parameters (KOH ratio and activation time), we have tailored the specific surface area (SSA) and pore size distribution (PSD) of the resulting carbon materials—crucial parameters that support supercapacitive performance. Several spectroscopic, morphological, and electrochemical techniques are used to characterize the obtained carbon materials. In particular, our optimization efforts revealed that a 5:1 KOH ratio with an activation time up to 120 min produced the highest SSA of about 2203 m2/g. Employing these optimal conditions, we fabricated symmetric coin cell supercapacitors using Na2SO4 as the electrolyte, which exhibited interesting specific capacitance (~56 F/g). Durability testing over 5000 cycles sustained the durability of the as-made activated carbon electrodes, suggesting an excellent retention of specific capacitance. This study not only advances the field of energy storage by introducing a renewable material for electrode fabrication but also contributes to the broader goal of waste reduction through the repurposing of food byproducts. [ABSTRACT FROM AUTHOR]

Several bulk transition-metal dichalcogenides exhibit a strong optical anisotropy, high refractive index, and even a natural hyperbolic response, which are enabling ingredients in a variety of nanophotonic scenarios of great interest. Here, we investigate the electromagnetic response of NiTe2, a type-II Dirac semimetal, whose infrared/optical properties have been hitherto largely unexplored. Through density-functional-theory-based ab initio modeling, along with electron energy loss spectroscopy experiments, we show that NiTe2 exhibits a varied, extremely anisotropic response within the infrared and visible ranges. We also demonstrate the high tunability of its optical properties and illustrate the key role played by Dirac fermions. Our results pave the way for realizing nanophotonic devices for efficient light manipulation at subwavelength scales. [ABSTRACT FROM AUTHOR]