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The utilization of bio-oil derived from biomass presents a promising alternative to fossil fuels, though it faces challenges when directly applied in diesel engines. Microemulsification has emerged as a viable strategy to enhance bio-oil properties, facilitating its use in hybrid fuels. This study explores the microemulsification of Jatropha bio-oil with ethanol, aided by a surfactant, to formulate a hybrid liquid fuel. Additionally, a bio-nano CaO heterogeneous catalyst synthesized from eggshells is employed to catalyse the production of Jatropha biodiesel from the microemulsified fuel using microwave irradiation. The catalyst is characterized through UV–Vis, XRD, and SEM analysis. The investigation reveals a significant reduction in CO, CO 2 , and NO X emissions with the utilization of microemulsion-based biodiesel blends. Various blends of conventional diesel, Jatropha biodiesel, and ethanol are prepared with different ethanol concentrations (5, 10, and 20 wt%). Engine performance parameters, including fuel consumption, NOX emission, and brake specific fuel consumption, are analyzed. Results indicate that the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend exhibits superior performance compared to conventional diesel, Jatropha biodiesel, and other blends. The fuel consumption of the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend is measured at 554.6 g/h, surpassing that of conventional diesel and other biodiesel blends. The presence of water (0.14 %) in the blend reduces the heating value, consequently increasing the energy requirement. CO and CO 2 emissions for the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend are notably lower compared to conventional C-18 hydrocarbons and various biodiesel blends. These findings accentuate the efficacy of the microemulsion process in enhancing fuel characteristics and reducing emissions. Further investigations could explore optimizing the emulsifying agents and their impact on engine performance and emission characteristics, contributing to the advancement of sustainable fuel technologies. • Prepare and characterize low-cost Bio-nano CaO catalyst from eggshells. • Microwave irradiation technique used for the preparation of Jatropha biodiesel from Jatropha oil. • Use ethanol for the microemulsification of Jatropha oil and blend with other fuels for engine performance analysis. • Biodiesel obtained through microemulsification process has good variability in its properties when used with fuel blends. • Design the experiment to find optimal conditions for NO x , CO, and CO 2 emissions and also to find the optimal blend composition to be used as fuel. [ABSTRACT FROM AUTHOR]

In this study, we studied the conversion of Jatropha curcas oil to biodiesel by using three distinct reactor systems: microchannel, fixed bed, and microwave reactors. ZSM-5 was used as the catalyst for this conversion and was thoroughly characterized. X-ray diffraction was used to identify the crystalline structure, Brunauer–Emmett–Teller analysis to determine surface area, and temperature-programmed desorption to evaluate thermal stability and acidic properties. These characterizations provided crucial insights into the catalyst's structural integrity and performance under reaction conditions. The microchannel reactor exhibited superior biodiesel yield compared to the fixed bed and microwave reactors, and achieved peak efficiency at 60 °C, delivering high FAEE yield (99.7%) and conversion rates (99.92%). Ethanol catalyst volume at 1% was optimal, while varying flow rates exhibited trade-offs, emphasizing the need for nuanced control. Comparative studies against microwave and fixed-bed reactors consistently favored the microchannel reactor, emphasizing its remarkable FAME percentages, high conversion rates, and adaptability to diverse operating conditions. The zig-zag configuration enhances its efficiency, making it the optimal choice for biodiesel production and showcasing promising prospects for advancing sustainable biofuel synthesis technologies. • Achieved high biodiesel efficiency with zig-zag microchannel reactor. • Optimized key parameters for max conversion rates and FAME percentages. • Reused ZSM-5 catalyst-maintained efficacy confirmed by XRD, BET, and TPD analyses. • Outperformed microwave and fixed-bed reactors in diverse conditions. • Showcased microchannel reactor's versatility and sustainability for biofuel synthesis. [ABSTRACT FROM AUTHOR]

The aim of the work is to find the efficiency of solar power in biodiesel preparation from mackerel fish. The paper also focusses on the ability of MgO/graphene prepared by one-pot synthesis using combustion methodology. The physicochemical properties of the material were analysed by XRD, N 2 sorption studies, BET sorption analysis and SEM. The adsorption studies revealed the porosity of the graphene is intact, and the morphology studies indicated that MgO is uniformly distributed on the graphene surface. The highest biodiesel yield of 98.95% was obtained using the solar-powered Fresnel solar concentrator at 12.30 p.m in 6 min reaction time using 3 wt% MgO/GO catalyst at 65 °C. Conventional heating produced only 75% biodiesel at the same reaction condition, consuming25 min to complete. The solar assisted biodiesel had better HHV of 37.81 MJ/Kg, viscosity of 4.3 mm2/s, pour point of −15 °C, and a density of 0.875 g/mL. The optimized catalyst showed a shelf life of 5 cycles. The results portray the efficacy of natural energy source in alternative liquid fuel production. • MgO/GO composite catalyst was synthesized and characterized. • Mackerel fish oil was chosen as the bioresource. • Fresnel solar concentration method was employed in biodiesel preparation. • Amidst the different techniques, solar assisted biodiesel worked effective in conversion of fish oil. • Blends of prepared biodiesel and diesel was compatible with ASTM standard. [ABSTRACT FROM AUTHOR]

A metal-free combination of rGO/g-C3N4-coupled SrTiO3 (SRN) ternary nanocomposite prepared via a wet impregnation method for UV–Vis light photocatalytic applications. Various physicochemical properties of the samples were investigated by several spectroscopic techniques including X-ray diffraction (XRD), FT-IR, Raman, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FE-SEM-EDX), high-resolution transmission electron microscopy (HR-TEM), UV–Vis, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) surface area analysis. The data suggest agglomerated SRT nanoparticles are dispersed and distributed throughout the surface of the rGO sheets and GCN nanostructures. The photocatalytic performance of the SRN towards combined mixed dye and its degradation activities were evaluated towards the most common industrial effluents, Rhodamine B (RhB) and Methylene blue (MB), under UV–Vis light illumination. The results revealed that the degradation efficiency of the SRN photocatalyst shows excellent performance compared with that of the binary composition and the pure SrTiO3 (SRT) sample. The reaction rate constant for RhB was estimated to be 0.0039 min−1 and for MB to be 0.0316 min−1, which are 3.26 (RhB) and 4.21 (MB) times faster than the pure SRT sample. The enhanced degradation efficiency was attained not only by interfacial formation but also by the speedy transportation of electrons across the heterojunction. After 5 runs of the photocatalytic recylic process, the SRN photocatalyst exhibited ultimate stability without structural changes, and no noticeable degradation was observed. The outcomes of the ternary SRN nanocomposite manifest a dual photocatalytic scheme, the photocatalytic enrichment could be caused by the Z-scheme charge transfer process between GCN, SRT, and rGO nanocomposite, which helps effectual charge separation and keeps a high redox potential. From the results, SRN sample provides insight into the integration of an effective and potential photocatalyst for wastewater treatment toward real-time environmental remediation applications. [ABSTRACT FROM AUTHOR]

Benzopyrene (BaP) stands as a potent polycyclic aromatic hydrocarbon (PAH) molecule, boasting five fused aromatic rings, making its way into the human food chain through soil contamination. The persistent environmental presence of PAHs in soil, attributed to industrial exposure, is primarily due to their low molecular weight and hydrophobic nature. To preemptively address the entry of BaP into the food chain, the application of nanocomposites was identified as an effective remediation strategy. Post-synthesis, comprehensive characterization tests employing techniques such as UV-DRS, XRD, SEM-EDX, FTIR, and DLS unveiled the distinctive features of the g–C 3 N 4 –SnS nanocomposites. These nanocomposites exhibited spherical shapes embedded on layers of nanosheets, boasting particle diameters measuring 88.9 nm. Subsequent tests were conducted to assess the efficacy of eliminating benzopyrene from a combination of PAH molecules and g–C 3 N 4 –SnS nanocomposites. Varied parameters, including PAH concentration, adsorbent dosage, and suspension pH, were systematically explored. The optimized conditions for the efficient removal of BaP utilizing the g–C 3 N 4 –SnS nanocomposite involved 2 μg/mL of benzopyrene, 10 μg/mL of the nanocomposite, and a pH of 5, considering UV light as the irradiation source. The investigation into the mechanism governing BaP elimination closely aligned with batch adsorption results involved a thorough exploration of adsorption kinetics and isotherms. Photocatalytic degradation of benzopyrene was achieved, reaching a maximum of 86 % in 4 h and 36 % in 2 h, with g–C 3 N 4 –SnS nanocomposite acting as the catalyst. Further validation through HPLC data confirmed the successful removal of BaP from the soil matrix. [Display omitted] • Synthesis and characterization of g–C 3 N 4 –SnS nanocomposites. • Examination of microbial inhibitory properties of g–C 3 N 4 –SnS nanocomposites. • Batch adsorption studies on benzopyrene elimination using g–C 3 N 4 –SnS nanocomposites. • Adsorption kinetics and isotherm studies on benzopyrene elimination using g–C 3 N 4 –SnS nanocomposites. • HPLC studies to confirm Benzopyrene elimination from the soil sample. [ABSTRACT FROM AUTHOR]

The rapid and wide dissemination of up‐to‐date, localized information is a central issue during disasters. Being attributed to the original 140‐character length, Twitter provides its users with quick‐posting and easy‐forwarding features that facilitate the timely dissemination of warnings and alerts. However, a concern arises with respect to the terseness of tweets that restricts the amount of information conveyed in a tweet and thus increases a tweetʼs uncertainty. We tackle such concerns by proposing entropy as a measure for a tweetʼs uncertainty. Based on the perspectives of Uncertainty Reduction Theory (URT), we theorize that the more uncertain information of a disaster tweet, the higher the entropy, which will lead to a lower retweet count. By leveraging the statistical and predictive analyses, we provide evidence supporting that entropy validly and reliably assesses the uncertainty of a tweet. This study contributes to improving our understanding of information propagation on Twitter during disasters. Academically, we offer a new variable of entropy to measure a tweetʼs uncertainty, an important factor influencing disaster tweetsʼ retweeting. Entropy plays a critical role to better comprehend URLs and emoticons as a means to convey information. Practically, this research suggests a set of guidelines for effectively crafting disaster messages on Twitter. [ABSTRACT FROM AUTHOR]

Depending on the severity of the injury or chemical dosages, injury due to vacuolization can be classified as reversible (where the nematodes can be revived back to life) or irreversible (where the nematodes pass the point of no return, causing them to die). Methuotic or vacuolar death in nematodes (a phenotype characterized by lopsided vacuolization) is often characterized by the formation of multiple vacuoles and their subsequent fusion to form giant vacuoles [[12]]. At sublethal dosages, 5-iodoindole induces small vacuoles on nematodes, but its supplementation with a fungal feed ( I Botrytis cinerea i ) allows surviving nematodes to recover [[12], [14]]. In conclusion, this opinion encourages scientists to synthetize, repurpose, or search for as of yet unknown vacuole-inducing chemicals and drugs that trigger water ingress and vacuole formation as apparent endpoint marker. [Extracted from the article]

The objective of the present study is to synthesize g-C3N4–Ni nanocomposites composed of graphitic carbon nitride and magnetic nickel nanoparticles for benzopyrene degradation, which is one of the most potent polycyclic aromatic hydrocarbons (PAH) molecules. The concocted g-C 3 N 4 –Ni nanocomposites contained confined nanospheres with a mean particle dimension of 22 nm. Batch adsorption studies revealed that a rise in adsorbent dosage elevates benzopyrene degradation percentage in both water and soil samples with respect to time. The increase in the benzopyrene concentration did not have much influence on the degradation efficiency, and hence, the minimal concentration of PAH molecule is essential for the effective adsorption by g-C 3 N 4 –Ni nanocomposites. The rise in pH tends to increase the degradation of Benzopyrene till 3 h of the incubation period, and beyond 3 h, the degradation percentage declines. With regard to the effect of light source, UV light has been shown to accelerate the degradation of benzopyrene by g-C 3 N 4 –Ni nanocomposites than sunlight. The adsorption kinetic and isotherm investigations have proven that the Pseudo-second order kinetic model and Freundlich isotherm model were appropriate for our study. Thus, the g-C 3 N 4 –Ni nanocomposites were found to be efficient as a photocatalyst for the adsorption of benzopyrene from environmental samples. • The concoction of g–C 3 N 4 –Ni nanocomposites was done through hydrothermal method. • Characterization of g–C 3 N 4 –Ni was carried out via SEM-EDAX, XRD, FTIR, and DLS. • Batch experiments on the degradation of benzopyrene (PAH) by g–C 3 N 4 –Ni was conducted. • Adsorbent conc, PAH conc, pH, and light source on benzopyrene adsorption was optimized. • Kinetic and isotherm studies reveal optimal conditions for effective PAH adsorption by g-C3N4–Ni. [ABSTRACT FROM AUTHOR]

Although there is a noticeable difference between two-dimensional and three-dimensional earth pressures, most researchers have suggested various earth pressure theories under the two-dimensional condition. Only a few studies have been conducted on the three-dimensional load transfer to the adjacent ground, whereas most studies in literature on the three-dimensional active earth pressure have been conducted by focusing on the stability of active wall. For accurate prediction of the three-dimensional active earth pressure, it is required to study not only the three-dimensional earth pressure distribution but also the three-dimensional load transfer to the adjacent ground. In this paper, size and distribution of the three-dimensional active earth pressure as well as the load transfer according to aspect ratio of retaining wall are investigated through a series of model tests. As a results, the three-dimensional active earth pressure distribution showed the highest value at the wall height of 0.5–0.55h when the aspect ratio of equal to 1.2 or higher. The load transfer showed higher values in vertical direction than horizontal direction. The load transfer distribution can be evaluated by applying the size and effect range of the loads transferred to the adjacent soil of the retaining wall. [ABSTRACT FROM AUTHOR]

The treatment of wastewater through the use of photocatalytic materials over semiconducting metal oxide has gained widespread interest as a promising new green and cheap technology. For the first time norfloxacin (NOR) antibiotic and methylene blue (MB) dye degradation was achieved by a simpler, cheaper, and faster technique for the preparation of NiO/ZnO heterostructure via NiO and its combined forms with ZnO catalysts under hydrothermal process. X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and X-ray photoelectron (XPS) spectroscopy were the techniques that were used to analyze the structure, morphology, and elemental contents, respectively. The Tauc plot using absorption spectra was used to determine the band energy value of pure NiO, ZnO, and NiO–ZnO catalysts. The results showed that the energy band gap of these materials was 3.15, 3.38, and 2.93 eV, respectively. All photocatalysts performed good efficiency within 50 min of irradiation, among these NiO/ZnO having superior activity (30 mg of catalyst, and 10 µM of dye and antibiotic). Under these conditions, the photocatalytic degradation efficiency of the produced NiO/ZnO materials for the NOR and MB dye was achieved at 96.73% and 97.38%, respectively. Inhibition of the recombination of electron-hole pairs by charge transfer processes may account for the high activity of the p-n-type NiO/ZnO heterostructures for the degradation of NOR and MB. Because of their strong photocatalytic activity, heterostructures based on semiconducting composites, such as NiO/ZnO, have great promise for use in future manufacturing processes aimed at cleaning our surroundings of harmful organic pollutants. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the scale and load distribution of three-dimensional active earth pressure and the load transferred to the adjacent soil by changing the aspect ratio of a retaining wall through a series of model tests. In this research, 42 earth pressure plates of different heights and widths were installed to evaluate the earth pressures by considering the wall aspect ratio and the change of earth pressure. The test results showed that the active earth pressures were uniformly converged when the percentage of limit displacement against wall height was 0.12%. The distribution of active earth pressure on the wall showed a parabola shape for most aspect ratios while the wedge shape identified by the model test was similar to the shell-shaped model. In this paper, two diagrams were proposed regarding the active earth pressure according to the aspect ratio of a retaining wall; (1) a diagram of earth pressure conversion against the aspect ratio based on evaluated three-dimensional active earth pressures with traditional two-dimensional earth pressures, (2) a load transfer diagram based on the horizontal distance by analyzing the horizontal and vertical load transfer ranges with the relevant increasing rates. [ABSTRACT FROM AUTHOR]

The use of sand compaction pile or gravel compaction pile is nowadays a common approach for soft ground improvement. In this article, a recycled aggregate porous concrete pile has been developed by replacing natural aggregates with recycled aggregates to overcome issues related to bulging failure or reduced section geometries. Such issues may arise during installation and during the early stages of operation. In addition, the proposed approach utilizes recycled aggregates instead of natural materials. To investigate the applicability of the recycled aggregate porous concrete pile method as a ground improvement technique, a series of laboratory model consolidation tests was performed on soft clay soil reinforced with sand compaction pile, gravel compaction pile, and recycled aggregate porous concrete pile, respectively. The results indicated that the settlement reduction effect of recycled aggregate porous concrete pile was significantly higher than the sand compaction pile and gravel compaction pile methods. The stress sharing ratio from the experimental program showed good agreement with those calculated by elasticity theory. Comparative analyses of the recycled aggregate porous concrete pile versus sand compaction pile and gravel compaction pile approaches, under the same replacement area ratio and surcharge pressure, showed significantly improved consolidation time, settlement reduction, and stress sharing effect. [ABSTRACT FROM PUBLISHER]

Bacterial colonization in the form of biofilms on surfaces causes persistent infections and is an issue of considerable concern to healthcare providers. There is an urgent need for novel antimicrobial or antibiofilm surfaces and biomedical devices that provide protection against biofilm formation and planktonic pathogens, including antibiotic resistant strains. In this context, recent developments in the material science and engineering fields and steady progress in the nanotechnology field have created opportunities to design new biomaterials and surfaces with anti-infective, antifouling, bactericidal, and antibiofilm properties. Here we review a number of the recently developed nanotechnology-based biomaterials and explain underlying strategies used to make antibiofilm surfaces. [ABSTRACT FROM AUTHOR]

Despite a large body of research on motivation in psychology, few in information systems have related it to the information and communication technology acceptance research. This study investigates the relation between the Self-Determination Theory of Motivation and the Unified Theory of Acceptance and Use of Technology (UTAUT) Model and confirms significant relationship across the two theories. In addition, this study investigates the effect of time sequential introduction of different types of motivation and finds the presence of the negative effect between intrinsic and extrinsic motivation is conditional on the type of extrinsic motivation. Controlled extrinsic motivation undermines intrinsic motivation that precedes it, but autonomous extrinsic motivation augments such intrinsic motivation. Implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

In the treatment of bacterial contamination, the problem of multi-drug resistance is becoming an increasingly pressing concern. Nanotechnology advancements enable the preparation of metal nanoparticles that can be assembled into complex systems to control bacterial and tumor cell growth. The current work investigates the green production of chitosan functionalized silver nanoparticles (CS/Ag NPs) using Sida acuta and their inhibition efficacy against bacterial pathogens and lung cancer cells (A549). Initially, a brown color formation confirmed the synthesis, and the chemical nature of the synthesized NPs were examined by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). FTIR demonstrated the occurrence of CS and S. acuta functional groups in the synthesized CS/Ag NPs. The electron microscopy study exhibited CS/Ag NPs with a spherical morphology and size ranges of 6–45 nm, while XRD analysis demonstrated the crystallinity of Ag NPs. Further, the bacterial inhibition property of CS/Ag NPs was examined against K. pneumoniae and S. aureus, which showed clear inhibition zones at different concentrations. In addition, the antibacterial properties were further confirmed by a fluorescent AO/EtBr staining technique. Furthermore, prepared CS/Ag NPs exhibited a potential anti-cancer character against a human lung cancer cell line (A549). In conclusion, our findings revealed that the produced CS/Ag NPs could be used as an excellent inhibitory material in industrial and clinical sectors. [ABSTRACT FROM AUTHOR]

An electrochemically active biofilm (EAB) was used for the synthesis of positively charged gold nanoparticles [(+)AuNPs] and in-situ hydrogen production without any external energy input. The EAB generate electrons and protons by decomposing sodium acetate (carbon source) in water at 30 °C. These electrons were used initially to reduce Au3+ to Au0, and later in-situ, these generated electrons and protons were used for hydrogen production. The as-synthesized (+)AuNPs acted as catalyst by providing a charged surface to reduce the protons, leading to the formation of molecular hydrogen according to the Volmer-Heyrovsky mechanism. The hydrogen produced was confirmed and estimated by gas chromatography and a fuel cell test, respectively. The maximum rate of hydrogen production reached ∼105 ± 2 mL/L day. This suggests that hydrogen production is possible in a single chamber reactor using an EAB in the presence of sodium acetate as a substrate and (+)AuNPs as a catalyst. [ABSTRACT FROM AUTHOR]

Only a few experimental studies have been performed on the response of piles subjected to combined loading, although the load applied on a pile is usually a combination of a vertical and a lateral load in practice. In addition, the experiment results available in the literature are inconsistent with respect to the effects of axial loads on the lateral capacity of piles. The objective of this paper is to assess the influence of axial loads on the lateral response of piles driven in sand through model pile combined load tests. Large-scale sand samples were prepared in a cylindrical steel tank with different relative densities (dense and loose) using a pluviation method, and an instrumented steel model pile was driven using a drop hammer. A series of lateral load tests were performed on the model piles subjected to different axial loads. The combined load test results demonstrated that the presence of an axial load on a driven pile is detrimental to its lateral capacity, for the bending moments and lateral deflection of the pile head increased substantially with increasing axial load. [ABSTRACT FROM AUTHOR]

A green and sustainable approach to azo dye degradation by an electrochemically active biofilm (EAB) with Au@TiO nanocomposite assistance (average size of Au ~8 nm) has been developed with high efficiency and mineralization of toxic intermediates. The EAB-Au@TiO system degraded the dye more rapidly than the EAB without the nanocomposite, which indicated the catalytic role of the Au@TiO nanocomposite on the dye degradation. Toxicity measurements showed that the dye wastewater treated by the EAB-Au@TiO system was almost non-toxic while the dye wastewater treated by the EAB without the nanocomposite showed a high toxicity compared to the parent dye. Quantized charging and Fermi level equilibration within the Au@TiO nanocomposite may be attributed to the excellent catalytic activity of the nanocomposite on the dye degradation. A mechanism of the catalytic activity is also proposed. Redox behavior and quantized charging of the nanocomposite were confirmed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), respectively. The proposed protocol can be effectively utilized in wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Abstract: Large scale applications of microbial fuel cells (MFCs) have been severely hindered by several problems such as high internal resistance, low power output, expensive materials, and complicated configuration. To address these issues, a granular activated carbon based single chamber microbial fuel cell (GACB-SCMFC) has been designed using GAC-biocathodes without using any expensive materials for the simultaneous decolorization of real dye wastewater and electricity generation. The GACB-SCMFC produced a power density of 8W/m3 which indicates the GAC-biocathode can be a good alternative to platinum and other chemical catalysts. The dye wastewater was primarily treated at the anode and further polishing steps were occurred at the aerobic cathode. Toxicity measurement shows that the effluent after GACB-SCMFC operation was much less toxic compared to the original dye wastewater. Additional advantage of the GACB-SCMFC is that pH was automatically adjusted from 12.2 to 8 during 48h of hydraulic retention time (HRT). [Copyright &y& Elsevier]

Decolorization of dye wastewater before discharge is pivotal because of its immense color and toxicities. In this study, a granular activated carbon based microbial fuel cell (GACB-MFC) was used without using any expensive materials like Nafion membrane and platinum catalyst for simultaneous decolorization of real dye wastewater and bioelectricity generation. After 48hours of GACB-MFC operation, 73% color was removed at anode and 77% color was removed at cathode. COD removal was 71% at the anode and 76% at the cathode after 48hours. Toxicity measurements showed that cathode effluent was almost nontoxic after 24hours. The anode effluent was threefold less toxic compared to original dye wastewater after 48hours. The GACB-MFC produced a power density of 1.7W/m3 with an open circuit voltage 0.45V. One of the advantages of the GACB-MFC system is that pH was automatically adjusted from 12.4 to 7.2 and 8.0 at the anode and cathode during 48hours operation. [ABSTRACT FROM AUTHOR]

Silver nanoparticles 1–7 nm in size were synthesized within 2 h in water by challenging an electrochemically active biofilm (EAB) with a solution containing AgNO3as precursor and sodium acetate as an electron donor. The electrochemically active bacteria present on the anaerobic biofilm act as a catalyst to oxidise the sodium acetate by producing electrons for the reduction of Ag+ions. The high monodispersity, rapidity, and extracellular nature of this synthesis, together with the production of smaller nanoparticles that are easily separated, make this protocol highly significant in the area of nanoparticle synthesis. [ABSTRACT FROM AUTHOR]

Silver nanoparticles 1–7 nm in size were synthesized within 2 h in water by challenging an electrochemically active biofilm (EAB) with a solution containing AgNO3 as precursor and sodium acetate as an electron donor. The electrochemically active bacteria present on the anaerobic biofilm act as a catalyst to oxidise the sodium acetate by producing electrons for the reduction of Ag+ ions. The high monodispersity, rapidity, and extracellular nature of this synthesis, together with the production of smaller nanoparticles that are easily separated, make this protocol highly significant in the area of nanoparticle synthesis. [ABSTRACT FROM AUTHOR]

The space of design alternatives for a business process is typically very large, with technology, location, and other factors combining to generate seemingly endless possibilities. This paper introduces a set of artifacts that support process designers in their efforts to manage this critical business problem: (1) a grammar-based method to generate and manage business process design alternatives and (2) a software prototype that provides support for the use of this method. The method and prototype software are demonstrated with a grammar for a sales process. The method improves on existing approaches by offering the generative power of grammar-based methods while addressing the principal challenge to using such approaches in the design of business processes: the limitations on automated evaluation of alternatives and thus the need to provide designers with tools to manage the potentially overwhelming array of choices generated by design grammars. [ABSTRACT FROM AUTHOR]

Abstract: The Escherichia coli gene cluster ymgABC was identified in transcriptome studies to have a role in biofilm development and stability. In this study, we showed that YmgB represses biofilm formation in rich medium containing glucose, decreases cellular motility, and protects the cell from acid indicating that YmgB has a major role in acid-resistance in E. coli. Our data show that these phenotypes are potentially mediated through interactions with the important cell signal indole. In addition, gel mobility-shift assays suggest that YmgB may be a non-specific DNA-binding protein. Using nickel-enrichment DNA microarrays, we showed that YmgB binds, either directly or indirectly, via a probable ligand, genes important for biofilm formation. To advance our understanding of the function of YmgB, we used X-ray crystallography to solve the structure of the protein to 1.8 Å resolution. YmgB is a biological dimer that is structurally homologous to the E. coli gene regulatory protein Hha, despite having only 5% sequence identity. This supports our DNA microarray data showing that YmgB is a gene regulatory protein. Therefore, this protein, which clearly has a critical role in acid-resistance in E. coli, has been renamed as AriR for regulator of acid resistance influenced by indole. [Copyright &y& Elsevier]

Analysis of the temporal development of Escherichia coli K-12 biofilms in complex medium indicates the greatest differential gene expression between biofilm and suspension cells occurred in young biofilms at 4 and 7 h (versus 15 and 24 h). The main classes of genes differentially expressed (biofilm versus biofilm and biofilm versus suspension cells) include 42 related to stress response (e.g. cspABFGI), 66 related to quorum sensing (e.g. ydgG, gadABC, hdeABD), 20 related to motility (e.g. flgBCEFH, fliLMQR, motB), 13 related to fimbriae (e.g. sfmCHM, fimZ, csgC), 24 related to sulfur and tryptophan metabolism (e.g. trpLBA, tnaLA, cysDNCJH), 80 related to transport (e.g. gatABC, agaBC, ycjJ, ydfJ, phoU, phnCJKM), and six related to extracellular matrix (e.g. wcaBDEC). Of the 93 mutants identified and studied, 76 showed altered biofilm formation. Biofilm architecture changed from thin and dense to globular and dispersed to dense and smooth. The quorum-sensing signal AI-2 controls gene expression most clearly in mature biofilms (24 h) when intracellular AI-2 levels are highest. Sulfate transport and metabolism genes ( cysAUWDN) and genes with unknown functions ( ymgABCZ) were repressed in young (4, 7 h) biofilms, induced in developed biofilms (15 h), and repressed in mature (24 h) biofilms. Genes related to both motility and fimbriae were induced in biofilms at all sampling time points and colanic acid genes were induced in mature biofilms (24 h). Genes related to dihydroxyacetone phosphate synthesis from galactitol and galactosamine (e.g. gatZABCDR, agaBCY) were highly regulated in biofilms. Genes involved in the biosynthesis of indole and sulfide ( tnaLA) are repressed in biofilms after 7 h (corroborated by decreasing intracellular indole concentrations in biofilms). Cold-shock protein transcriptional regulators ( cspABFGI) appear to be positive biofilm regulators, and deletions in respiratory genes (e.g. hyaACD, hyfCG, appC, narG) increased biofilm formation sevenfold. [ABSTRACT FROM AUTHOR]

We previously discovered that yliH and yceP are induced in Escherichia coli biofilms (D. Ren, L. A. Bedzyk, S. M. Thomas, R. W. Ye, and T. K. Wood, Appl. Microbiol. Biotechnol. 64:515–524, 2004). Here, it is shown that deletion of yceP (b1060) and yliH (b0836) increases biofilm formation in continuous-flow chambers with minimal glucose medium by increasing biofilm mass (240- to 290-fold), surface coverage (16- to 31-fold), and mean thickness (2,800-fold). To determine the genetic basis of the increase in biofilm formation, we examined the differential gene expression profile in biofilms for both the mutants relative to the wild-type strain in rich medium with glucose and found that 372 to 882 genes were induced and that 76 to 337 were repressed consistently >2-fold (P ≤ 0.05). The increase in biofilm formation was related to differential expression of genes related to stress response (8 to 64 genes) for both mutants, including rpoS and sdiA. More importantly, 42 to 130 genes related to autoinducer 2 cell signaling were also differentially expressed, including gadAB and flgBCEGHIJLMN, as well as signaling through indole, since 17 to 26 indole-related genes were differentially expressed, including phoAER, gltBD, mtr (encodes protein for indole import), and acrEF (encodes proteins for indole export). Increased biofilm formation in the yliH and yceP mutants in LB supplemented with 0.2% glucose (LB glu) occurred through a reduction in extracellular and intracellular indole concentrations in both mutants (50- to 140-fold), and the addition of indole to the culture restored the wild-type biofilm phenotype; hence, indole represses biofilms. Additionally, both mutants regulate biofilms through quorum sensing, since deletion of either yliH or yceP increased extracellular autoinducer 2 concentrations 50-fold when grown in complex medium (most notably in the stationary phase). Both proteins are involved in motility regulation, since YliH (127 amino acids) and YceP (84 amino acids) repressed motility two to sevenfold (P < 0.05) in LB, and YceP repressed motility sevenfold (P ≤ 0.05) in LB glu. Heightened motility in the yceP mutant occurred, due to increased transcription of the flagella and motility loci, including fliC, motA, and qseB (3- to 86-fold). We propose new names for these two loci: bssR for yliH and bssS for yceP, based on the phrase ‘regulator of biofilm through signal secretion.’ [ABSTRACT FROM AUTHOR]

Specialization has been used in object-oriented technologies to provide a number of powerful benefits such as modularity, maintainability, and comprehensibility. For the most part, however, system behavior continues to be modeled using traditional tools such as state diagrams and dataflow diagrams, which remain outside the scope of the specialization hierarchy used to such advantage with objects. This paper presents a framework for extending the notion of specialization to these process representations by identifying a set of transformations which, when applied to a process description, always result in specialization. We then use this framework to define specialization for dataflow diagrams. We illustrate with specific examples that such a use of specialization is not only theoretically possible, but shows promise as a method for categorizing and analyzing processes. [Copyright &y& Elsevier]

Staphylococcus aureus biofilm formation is a pivotal mechanism in the development of drug resistance, conferring resilience against conventional antibiotics. This study investigates the inhibitory effects of Actinostemma lobatum (A. lobatum) Maxim extracts on S. aureus biofilm formation and their antihemolytic activities, with a particular focus on identifying the active antibiofilm and antihemolysis compound, quercetin. Seven solvent extracts and twelve sub-fractions were evaluated against four S. aureus strains. The ethyl acetate fraction (10 to 100 μg/mL) significantly hindered biofilm formation by both methicillin-sensitive and -resistant strains. Bioassay-guided isolation of the ethyl acetate extract identified quercetin as the major antibiofilm compound. The ethyl acetate extract was found to contain 391 μg/mg of quercetin and 30 μg/mg of kaempferol. Additionally, the A. lobatum extract exhibited antihemolytic activity attributable to the presence of quercetin. The findings suggest that quercetin-rich extracts from A. lobatum and other quercetin-rich foods and plants hold promise for inhibiting resilient S. aureus biofilm formation and attenuating its virulence. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus, particularly drug-resistant strains, poses significant challenges in healthcare due to its ability to form biofilms, which confer increased resistance to antibiotics and immune responses. Building on previous knowledge that several flavonoids exhibit antibiofilm activity, this study sought to identify a novel flavonoid capable of effectively inhibiting biofilm formation and virulence factor production in S. aureus strains including MRSA. Among the 19 flavonoid-like compounds tested, 3,2′-dihydroxyflavone (3,2′-DHF) was identified for the first time as inhibiting biofilm formation and virulence factors in S. aureus with an MIC 75 µg/mL. The antibiofilm activity was further confirmed by microscopic methods. Notably, 3,2′-DHF at 5 µg/mL was effective in inhibiting both mono- and polymicrobial biofilms involving S. aureus and Candida albicans, a common co-pathogen. 3,2′-DHF reduces hemolytic activity, slime production, and the expression of key virulence factors such as hemolysin gene hla and nuclease gene nuc1 in S. aureus. These findings highlight the potential of 3,2′-DHF as a novel antibiofilm and antivirulence agent against both bacterial and fungal biofilms, offering a promising alternative to traditional antibiotics in the treatment of biofilm-associated infections. [ABSTRACT FROM AUTHOR]

As contemporary technology advances, scientists are striving to identify new approaches to managing several diseases. Compared to the more popular physiochemical synthesis, the plant-derived combination of metallic nanoparticles using plant secondary metabolites as a precursor has a number of benefits, including low expenses, low energy consumption, biocompatibility, and medicinal usefulness. This study intends to explore the impacts of using plant-derived synthetic materials including metallic nanoparticles (NPs), emphasizing the benefits of their broad use in next-generation treatments for cancer, diabetes, Alzheimer's, and vector diseases. This comprehensive analysis investigates the potential of plant-derived remedies for diseases and looks at cutting-edge nanoformulation techniques aimed at addressing the function of the nanoparticles that accompany these organic substances. The purpose of the current review is to determine how plant extracts contribute to the synthesis of Silver nanoparticles (AgNPs), Gold nanoparticles (GtNPs), and platinum nanoparticles (PtNPs). It provides an overview of the many phytocompounds and their functions in biomedicine, including antibacterial, antioxidant, anticancer, and anti-inflammatory properties. Furthermore, this study placed a special focus on a range of applications, including drug delivery systems, diagnostics and therapy, the present benefits of nanoparticles (NPs), their biomedical uses in medical technology, and their toxicities. [ABSTRACT FROM AUTHOR]

Focuses on design rationales, tools in design technology. Why design rationales are important tools; Benefits of well-structured design rationales; Impossibility of representing an entire design rationale explicitly; Description of approaches through which design rationales can be produced; Integration of the design rationale system with all aspects of design activities.

[Display omitted] • Supervised ML models were used to predict biogas yield and methane composition. • 5 different ML algorithms were considered including SVM, DT, ET, GPR, and KNN. • Critical parameters that affect the BGP prediction were OLR and HRT, and C/N ratio. • SVM predicted the best accuracy with an R2 value of 0.91. • No significant difference was found between 2-datasets (p = 0.377). Biogas production through anaerobic digestion (AD) is one of the complex non-linear biological processes, wherein understanding its dynamics plays a crucial role towards process control and optimization. In this work, a machine learning based biogas predictive model was developed for high solid systems using algorithms, including SVM, ET, DT, GPR, and KNN and two different datasets (Dataset-1:10, Dataset-2:5 inputs). Support Vector Machine had the highest accuracy (R2) of all the algorithms at 91 % (Dataset-1) and 87 % (Dataset-2), respectively. The statistical analysis showed that there was no significant difference (p = 0.377) across the datasets, wherein with less inputs, accurate results could be predicted. In case of biogas yield, the critical factors which affect the model predictions include loading rate and retention time. The developed high solid machine learning model shows the possibility of integrating Artificial Intelligence to optimize and control AD process, thus contributing to a generic model for enhancing the overall performance of the biogas plant. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli O157:H7 (EHEC) is responsible for outbreaks of hemorrhagic colitis worldwide, but no effective therapy exists for EHEC infections. EHEC readily forms antimicrobial-tolerant biofilms on various biotic and abiotic surfaces. Here, we investigated the antimicrobial and antibiofilm abilities of 16 halogenated (fluoro-, chloro-, bromo-, or iodo-) indoles and indole against a pathogenic EHEC strain. Antibiofilm activities followed the order chloroindoles > bromoindoles > indole > fluoroindoles. For example, the minimum inhibitory concentrations (MICs) of 4-bromoindole and 5-bromoindole were 100 and 200 μg/mL, respectively, and at 20 μg/mL, they both inhibited EHEC biofilm formation by more than 61% without affecting planktonic cell growth. However, at concentrations greater than their MICs, both showed bactericidal activity. Antibiofilm effects were confirmed by scanning electron microscopy. Both 4-bromoindole and 5-bromoindole reduced swimming and swarming motility and curli formation, which are important factors for EHEC biofilm formation. Furthermore, quantitative structure–activity relationship analysis demonstrated that halogenation of indole with chlorine, bromine, or iodine at positions C-4 or C-5 promotes antimicrobial activity but that substitution at C-7 is detrimental. The study shows that halogenated indoles, particularly bromoindoles, have potential use as antimicrobial and antibiofilm therapies against EHEC. [ABSTRACT FROM AUTHOR]

Food-related illnesses have become a growing public concern due to their considerable socioeconomic and medical impacts. Vibrio parahaemolyticus and Staphylococcus aureus have been implicated as causative organisms of food-related infections and poisoning, and both can form biofilms which confer antibiotic resistance. Hence, the need for continuous search for compounds with antibiofilm and antivirulence properties. In this study, 22 iodinated hydrocarbons were screened for their antibiofilm activity, and of these, iodopropynyl butylcarbamate (IPBC) was found to effectively control biofilm formation of both pathogens with a MIC of 50 µg/mL which was bactericidal to V. parahaemolyticus and S. aureus. Microscopic studies confirmed IPBC inhibits biofilm formation of both bacteria and also disrupted their mixed biofilm formation. Furthermore, IPBC suppressed virulence activities such as motility and hemolytic activity of V. parahaemolyticus and the cell surface hydrophobicity of S. aureus. It exhibited a preservative potential against both pathogens in a shrimp model. IPBC disrupted the cell membrane of S. aureus and V. parahaemolyticus and differentially affected gene expressions related to biofilm formation and virulence. Additionally, it displayed broad-spectrum antibiofilm activities against other clinically relevant pathogens. These findings indicate IPBC offers a potential means of controlling infections mediated by Vibrio and Staphylococcus biofilms. [ABSTRACT FROM AUTHOR]

Novel flake-like Ni1−xSnxO2 particles were successfully prepared by template-free hydrothermal synthesis. The prepared samples were investigated for their properties by different characterization techniques. Scanning micrographs showed that the obtained particles consisted of nanoflakes. The X-ray diffraction results of the Ni1−xSnxO2 revealed the formation of mixed-phase Ni/SnO2 having the typical tetragonal structure of SnO2, and the cubic structure of Ni in a nanocrystalline nature. The doping with Ni had a certain influence on the host's lattice structure of SnO2 at different doping concentrations. Confirmation of the functional groups and the elements in the nanomaterials was accomplished using FTIR and EDS analyses. The electrochemical performance analysis of the prepared nanomaterials were carried out with the help of the CV, GCD, and EIS techniques. The specific capacitance of the synthesized nanomaterials with different concentrations of Ni dopant in SnO2 was analyzed at different scanning rates. Interestingly, a 5% Ni-doped SnO2 nanocomposite exhibited a maximum specific capacitance of 841.85 F g−1 at 5 mV s−1 in a 6 M KOH electrolyte. Further, to boost the electrochemical performance, a redox additive electrolyte was utilized, which exhibited a maximum specific capacitance of 2130.33 at 5 mV s−1 and an excellent capacitance retention of 93.22% after 10,000 GCD cycles. These excellent electrochemical characteristics suggest that the Ni/SnO2 nanocomposite could be utilized as an electrode material for high-performance supercapacitors. [ABSTRACT FROM AUTHOR]

Indole and its derivatives are widespread across different life forms, functioning as signalling molecules in prokaryotes and with more diverse roles in eukaryotes. A majority of indoles found in the environment are attributed to bacterial enzymes converting tryptophan into indole and its derivatives. The involvement of indoles among lower organisms as an interspecies and intraspecies signal is well known, with many reports showing that inter‐kingdom interactions involving microbial indole compounds are equally important as they influence defence systems and even the behaviour of higher organisms. This review summarizes recent advances in our understanding of the functional properties of indole and indole derivatives in diverse eukaryotes. Furthermore, we discuss current perspectives on the role of microbial indoles in human diseases such as diabetes, obesity, atherosclerosis, and cancers. Deciphering the function of indoles as biomarkers of metabolic state will facilitate the formulation of diet‐based treatments and open unique therapeutic opportunities. [ABSTRACT FROM AUTHOR]

Microbial biofilms are protected surface-attached communities of bacteria or fungi with high drug tolerance that typically cause persistent infections. Smart drug carriers are being explored as a promising platform of antimicrobials to address their recalcitrance to antibiotic agents and minimize the side effects of current therapies. In this study, soy lecithin liposomes loaded with lauric acid (LA) and myristoleic acid (MA) were formulated using an emulsification method, and their antibiofilm properties were evaluated. The physio-chemical properties of the most potent liposome were characterized using a zeta sizer, transmission electron microscopy (TEM), fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. TEM and zeta sizer analysis of the liposome revealed a homogeneous spherical structure with an average size of 159.2 nm and zeta potential of − 5.4 mV. The unilamellar liposomes loaded with LA at 0.1–0.5 µg/mL achieved obvious antibiofilm efficiency against Staphylococcus aureus and Candida albicans and their dual biofilms. Also, LA-loaded liposome formulation efficiently disrupted preformed biofilms of S. aureus and C. albicans. Furthermore, formulated liposomal LA (0.1 µg/mL) exhibited 100-fold increased dual biofilm inhibition compared to LA alone. The single biofilms and dual biofilm formation on polystyrene were reduced as determined by 3D-bright field and scanning electron microscopy. Zeta potential measurements exhibited neutralized surface charge of S. aureus , and the liposomes inhibited hyphae formation in C. albicans. These findings demonstrated that the LA-incorporated liposomes have great potential to become a new, effective, and good antibiofilm agent for treating S. aureus and C. albicans infections. [Display omitted] • Lecithin-fatty acid liposomes were synthesized through an emulsification technique. • The liposome 100-fold enhanced antibiofilm activity of polymicrobial biofilms. • The liposomes efficiently disrupted preformed biofilms of S. aureus and C. albicans. • The fatty acid liposomes are new delivery systems to control persistent infections. [ABSTRACT FROM AUTHOR]

[Display omitted] • MoS 2 -Bi 2 Te 3 -V 2 O 5 NCs has been prepared through wet impregnation method. • MoS 2 -Bi 2 Te 3 -V 2 O 5 NCs revealed its high stability and excellent durability. • Hydroxyl radicals show a significant role in the dye decomposition process. Researchers have become increasingly interested in solar energy based on semiconductor photocatalysts to remove hazardous pollutants and clean the environment. In this work, an efficient MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite has been prepared through wet impregnation method. MoS 2 -Bi 2 Te 3 -V 2 O 5 photocatalyst was utilized to decompose the MB and Rh B dyes. The photocatalytic efficiency (Rh B) of MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite (95.19 %) was higher than 2.70 times of Bi 2 Te 3 nanorods, 1.55 times of V 2 O 5 nanoparticles, 1.68 times of MoS 2 nanosheets, 1.50 times of MoS 2 -Bi 2 Te 3, and 1.21 times of MoS 2 -V 2 O 5 nanocomposite, respectively. Recycling tests conducted on the MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite revealed its high stability and durability. The outcomes obtained from the scavenger test suggest that the photogenerated hydroxyl radicals play a chief role in the photocatalytic performance of Rh B dye in the MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite, respectively. The enhanced photocatalytic performance of the MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite is ascribed to the strong hybrid formation of Bi 2 Te 3 , V 2 O 5 , and MoS 2 nanosheets, respectively. Consequently, the straightforward and readily synthesized MoS 2 -Bi 2 Te 3 -V 2 O 5 nanocomposite can serve as an economical, highly effective material for environmental applications. [ABSTRACT FROM AUTHOR]

Uropathogenic Escherichia coli (UPEC) is a urinary tract pathogen responsible for most nosocomial urinary tract infections and can cause severe conditions like acute cystitis of the bladder or pyelonephritis. UPEC harbors a host of virulence factors like curli, hemolysin, siderophore, and motility factors and can form biofilm-like communities and quiescent reservoirs that aid its survival. This study was performed to investigate the antibiofilm, antimicrobial, and antivirulence potentials of three chromone derivatives, namely, 6-bromo 3-formylchromone, 6-chloro 3-formylchromone, and 3-formyl 6-isopropylchromone. These chromones had MICs against UPEC of 20, 20, and 50 µg/ml, respectively, inhibited biofilm formation by 72–96% at 20 µg/ml, and inhibited UPEC-associated virulence factors, that is, hemolysis, motility, curli, siderophore production, indole production, quiescent colony formation, and cell surface hydrophobicity. Gene expression analysis indicated these three derivatives downregulated virulence genes associated with toxins, biofilm production, and stress regulation and suggested they might target two-component UvrY response regulator. 3D-QSAR analysis showed that substitutions at the third and sixth positions of the chromone scaffold favor antimicrobial activity against UPEC. Furthermore, ADME profiles and C. elegans cytotoxicity assays indicated that these chromone derivatives are potent, safe drug candidates. [ABSTRACT FROM AUTHOR]

Drug repurposing is an anticipative chemotherapeutic strategy that accentuates the inadequacy of antifungal drugs. The study identifies an antipsychotic drug, aripiprazole, as a biofilm and hyphal inhibitor of Candida albicans. Microtitre plate biofilm inhibition, metabolic activity and hyphal inhibitory assays were used to assess the potency of aripiprazole; and filipin staining, reactive oxygen species staining, cAMP rescue, propidium iodide staining, computational studies and qRT-PCR assays were used to elucidate its mode of action. The study revealed aripiprazole functioned in a manner similar to standard azoles, particularly the imidazole, ketoconazole, by inhibiting pseudohyphal formation during the early stages of hyphal development. The action of aripiprazole on C. albicans was dose-dependent and it exhibited varied mechanisms of action at low and high dosages. At low dosage, aripiprazole outperformed ketoconazole in terms of inhibiting biofilm formation, hyphal filamentations, and yeast flocculation, whereas at higher dosage it mimicked ketoconazole. This study illustrates the anti-candidal potential and mechanistic activities of aripiprazole, and indicates the future use of this drug as an anti-biofilm agent. [ABSTRACT FROM AUTHOR]

HAp-α-MnO 2 -Co 3 O 4 nanocomposite was prepared by the wet impregnation technique. Various analytical techniques were used to study the structural, morphology and photophysical characteristics. In the present study, the degradation of MB dye under the visible light irradiation in existence of HAp-α-MnO 2 -Co 3 O 4 nanocomposite has been examined and the detailed mechanism for the photocatalytic degradation was discussed. The improved photocatalytic degradation activity over the HAp-α-MnO 2 -Co 3 O 4 nanocomposite can be ascribed to the efficient high generation and low recombination rate of charge carriers under the UV-Visible light. Also, the key features for HAp-α-MnO 2 -Co 3 O 4 nanocomposite including enhancement of light absorbance, recombination rate of photogenerated charge carriers have also been found for the nanocomposites. Based on photocatalytic degradation, it was found that the HAp-α-MnO 2 -Co 3 O 4 nanocomposite has the highest photocatalytic activity among all freshly prepared samples. In particular, the MB dye was almost completely degraded (95.5 %) by exposure to UV–visible light in 60 min of irradiation, the observed degradation result was relatively higher than that of pristine HAp, α-MnO 2 and Co 3 O 4 , respectively. HAp-α-MnO 2 -Co 3 O 4 nanocomposite efficiently degraded 94.42 % colorless phenol, demonstrating its dual ability to break down hazardous dyes and organic compounds under the same conditions. In addition, the HAp-α-MnO 2 -Co 3 O 4 nanocomposite has a good recyclability of 90.25 % after five successive cycles. These observed results show that the HAp-α-MnO 2 -Co 3 O 4 nanocomposite is an environmentally friendly material for environmental remediation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The hydrogel based composite film was prepared from k -Carrageenan (k -C), xanthan gum (X) and gellan gum (G) by solvent casting method. The transparent films made from these gellable materials with synergistic hydrogel composition have soft texture, good elasticity and excellent break strength. The k -C/X/G based nanocomposite films prepared from different weight ratio of TiO 2 nanoparticles were characterized for new packaging materials. The morphology, structure and microstructure properties of the k -C/X/G and TiO 2 nanocomposite films were characterized by FT-IR, XRD and SEM analysis. By the incorporation of TiO 2 in the k -C/X/G nanocomposite films, the tensile strength, tensile modulus, T g and thermal stability of the films were greatly enhanced. Due to the hydrophobic nature of the TiO 2 nanoparticles there is an increase in contact angle whereas moisture content of the films decreased. The water vapor permeability (WVP) and ultra violet lights transmittance decrease upon increasing the TiO 2 content. The k -C/X/G and TiO 2 nanocomposites effectively shield the UV light, exhibited partial microbial activity against Staphylococcus aureus and have a high potential for the application in food and non-food industries as UV shielding packaging materials. Highlights • Fabrication of TiO 2 based k-C/X/G nanocomposite films by solution casting method. • TiO 2 increased the hydrophobic nature of the films. • The nanocomposite films improved their thermal stability, mechanical and water barrier properties compared with neat films. • These nanocomposite films developed for food packaging applications. [ABSTRACT FROM AUTHOR]

Summary: Certain pathogenic bacteria and yeast form biofilms on biotic and abiotic surfaces including medical devices and implants. Hence, the development of antibiofilm coating materials becomes relevant. The virulence of those colonizing pathogens can be reduced by inhibiting biofilm formation rather than killing pathogens using excessive amounts of antimicrobials, which is touted as one of the main reasons for the development of drug resistance. Candida albicans is an opportunistic fungal pathogen, and the transition of yeast cells to hyphal cells is believed to be a crucial virulence factor. Previous studies have shown that indole and its derivatives possess antivirulence properties against various bacterial pathogens. In this study, we used various indole derivatives to investigate biofilm‐inhibiting activity against C. albicans. Our study revealed that 7‐benzyloxyindole, 4‐fluoroindole and 5‐iodoindole effectively inhibited biofilm formation compared to the antifungal agent fluconazole. Particularly, 7‐benzyloxyindole at 0.02 mM (4.5 μg ml−1) significantly reduced C. albicans biofilm formation, but had no effect on planktonic cells, and this finding was confirmed by a 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide (XTT) assay and three‐dimensional confocal laser scanning microscopy. Scanning electron microscopy analyses revealed that 7‐benzyloxyindole effectively inhibited hyphal formation, which explains biofilm inhibition. Transcriptomic analysis showed that 7‐benzyloxyindole downregulated the expressions of several hypha/biofilm‐related genes (ALS3,ECE1,HWP1 and RBT1). A C. albicans‐infected Caenorhabditis elegans model system was used to confirm the antivirulence efficacy of 7‐benzyloxyindole. 7‐Benzyloxyindole could be used to control fungal virulence by regulating hyphae‐specific genes and to treat biofilm associated infections on medical implant devices and Candidiasis infections. [ABSTRACT FROM AUTHOR]

We report on the synthesis of silver oxide/reduced graphene oxide nanocomposites (Ag/rGO NCs) using a hydrothermal technique. This paper presents a simple method for synthesizing Ag/rGO hybrid nanocomposites, which can be used for environmentally treating hazardous organic pollutants. The photocatalytic degradation of model artificial Rhodamine B dye and bisphenol A was assessed under visible light illumination. The crystallinity, binding energy, and surface morphologies of the synthesized samples were determined. The silver oxide loading sample resulted in a decrease in the rGO crystallite size. SEM and TEM images demonstrate strong adhesion of the Ag NPs to the rGO sheets. XPS analysis validated the binding energy and elemental composition of the Ag/rGO hybrid nanocomposites. The objective of the experiment was to enhance the photocatalytic efficiency of rGO in the visible region using Ag nanoparticles. The synthesized nanocomposites in the visible region exhibited good photodegradation percentages of approximately 97.5% and 98.6% after 120 min of irradiation for pure rGO, Ag NPs, and Ag/rGO nanohybrid, respectively. Furthermore, the Ag/rGO nanohybrid maintained their degradation ability for up to three cycles. The synthesized Ag/rGO nanohybrid demonstrated enhanced photocatalytic activity, expanding their potential for environmental remediation. Based on the investigations, Ag/rGO nanohybrid proved to be an effective photocatalyst and holds promise as an ideal material for future applications in preventing water pollution. [Display omitted] • Ag/rGO hybrid nanocomposites were synthesized by a simple and hydrothermal technique. • The characterizations of the as-prepared Ag/rGO NCs have been determined by XRD, SEM, TEM, and XPS analysis. • Ag/rGO NCs catalyst exhibited high stability during recycle test. • Excellent photocatalytic degradation performance was obtained. [ABSTRACT FROM AUTHOR]

Nanozymes represent a category of nano-biomaterial artificial enzymes distinguished by their remarkable catalytic potency, stability, cost-effectiveness, biocompatibility, and degradability. These attributes position them as premier biomaterials with extensive applicability across medical, industrial, technological, and biological domains. Following the discovery of ferromagnetic nanoparticles with peroxidase-mimicking capabilities, extensive research endeavors have been dedicated to advancing nanozyme utilization. Their capacity to emulate the functions of natural enzymes has captivated researchers, prompting in-depth investigations into their attributes and potential applications. This exploration has yielded insights and innovations in various areas, including detection mechanisms, biosensing techniques, and device development. Nanozymes exhibit diverse compositions, sizes, and forms, resembling molecular entities such as proteins and tissue-based glucose. Their rapid impact on the body necessitates a comprehensive understanding of their intricate interplay. As each day witnesses the emergence of novel methodologies and technologies, the integration of nanozymes continues to surge, promising enhanced comprehension in the times ahead. This review centers on the expansive deployment and advancement of nanozyme materials, encompassing biomedical, biotechnological, and environmental contexts. [ABSTRACT FROM AUTHOR]

The objective of the present study was to develop a one-pot strategy to synthesis gold nanoparticle complexes using cinnamaldehyde, a potent antibiofilm agent which in its free form, exhibits high volatility and unstable nature. Hence, we developed cinnamaldehyde gold nanoparticles (CGNPs) in a single step to overcome the limitations of free cinnamaldehyde. Furthermore, reduction abilities of cinnamaldehyde under different experimental conditions, that is, varying precursor concentrations of cinnamaldehyde and gold, metal salts, pH, temperature, and light sources, were investigated. UV–vis spectroscopy, transmission electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and dynamic light-scattering measurements revealed that heat influenced the nanoparticle formation in the presence of cinnamaldehyde, and as produced cinnamaldehyde immobilized on gold nanoparticles were spherical, monodispersed, and stable by surface charge. CGNPs containing 0.01% cinnamaldehyde by weight exhibited effective biofilm inhibition of up to >80% against Gram positive bacteria (methicillin-sensitive and -resistant strains of Staphylococcus aureus, MSSA and MRSA, respectively) and Gram negative ( Escherichia coli and Pseudomonas aeruginosa ) and a fungus Candida albicans . In addition, CGNPs attenuated the virulence of C. albicans by inhibiting hyphae formation. Based on observations of their antibiofilm effects and confocal microscopy findings, CGNPs caused biofilm damage by direct contact. Thus, cinnamaldehyde appears to be a promising reduction material for the eco-friendly, one-pot synthesis of CGNPs with excellent antibiofilm activity. [ABSTRACT FROM AUTHOR]

Supercapacitors are attracting attention as energy storage devices but the energy density and cycle life of electrode materials require further improvement for commercial applications. To achieve this goal, a corn flake-like NiO nanostructure on nickel foam was synthesized using a facile electrodeposition method. X-ray diffraction, high resolution transmission electron microscopy, and field emission scanning electron microscopy confirmed the formation of a corn flake-like NiO nanostructure on nickel foam. The electrochemical properties of the as-prepared NiO nanostructure were analyzed by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The direct formation of a highly porous corn flake-like NiO nanostructure on nickel foam provided an excellent electronic charge transfer rate with a low equivalent series resistance and good ionic accessibility for strong supercapacitive behavior. The as-prepared NiO nanostructure on nickel foam exhibited a specific capacitance of 1717 F g−1 and a capacitance retention of 87% after 5000 cycles. The NiO//activated carbon asymmetric supercapacitor fabricated using a polyvinyl alcohol-KOH gel electrolyte showed high energy and power densities of 44 W h kg−1 and 14 kW kg−1, respectively. Overall, the corn flake-like NiO nanostructure on nickel foam is an excellent candidate for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Biofilms are responsible for persistent or recurring microbial infections. Polymicrobial biofilms are prevalent in environmental and medical niches. Dual-species biofilms formed by Gram-negative uropathogenic Escherichia coli (UPEC) and Gram-positive Staphylococcus aureus are commonly found in urinary tract infection sites. Metal oxide nanoparticles (NPs) are widely studied for their antimicrobial and antibiofilm properties. We hypothesized that antimony-doped tin (IV) oxide (ATO) NPs, which contain a combination of antimony (Sb) and tin (Sn) oxides, are good antimicrobial candidates due to their large surface area. Thus, we investigated the antibiofilm and antivirulence properties of ATO NPs against single- and dual-species biofilms formed by UPEC and S. aureus. ATO NPs at 1 mg/mL significantly inhibited biofilm formation by UPEC, S. aureus, and dual-species biofilms and reduced their main virulence attributes, such as the cell surface hydrophobicity of UPEC and hemolysis of S. aureus and dual-species biofilms. Gene expression studies showed ATO NPs downregulated the hla gene in S. aureus, which is essential for hemolysin production and biofilm formation. Furthermore, toxicity assays with seed germination and Caenorhabditis elegans models confirmed the non-toxic nature of ATO NPs. These results suggest that ATO nanoparticles and their composites could be used to control persistent UPEC and S. aureus infections. [ABSTRACT FROM AUTHOR]