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New, effective antimicrobial agents are constantly being evaluated for addressing the increased prevalence of bacterial and fungal infections and emerging drug resistance. In this study, α-Ag2WO4 microcrystals were prepared by controlled coprecipitation (90 °C for 10 min) in different solvents (e.g., water, an alcoholic solution, and an ammoniacal solution). From the X-ray diffraction results, the newly synthesized α-Ag2WO4 microcrystals are well-indexed to the orthorhombic structure. Two morphologies were seen by field-emission scanning electron microscopy: microrods in the alcoholic solution and flowerlike structures in water and the ammoniacal solution. The synthesized α-Ag2WO4 microcrystals exhibited antimicrobial activity against Candida albicans, Escherichia coli, and methicillin-resistant Staphylococcus aureus. In addition, the antibacterial performance of the α-Ag2WO4 samples as a function of their structural and morphological features was discussed. [ABSTRACT FROM AUTHOR]

In this communication, we report for the first time the nucleation and growth of metallic Ag nanoparticles on the surface of 3D flower-like Ag4V2O7 crystals, induced by accelerated electron beam irradiation. The growth of metallic Ag on the surfaces of Ag4V2O7 crystals were studied by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDXS). According to TEM images and EDXS analyses, exposure to the electron beam induces a reduction process and the growth of metallic Ag nanoparticles on the surface of Ag4V2O7 crystals. Moreover, the inductively coupled plasma optical emission spectrometry measurements indicated an excess of Ag and V vacancies at Ag4V2O7 lattice. Finally, it was observed that the electrical resistance varies considerably with the exposure time to electron beam irradiation. [ABSTRACT FROM AUTHOR]

CaTiO 3 (CT) and α -Ag 2 WO 4 (AW) semiconductors are widely known for their interesting electrical and photoluminescence (PL) properties. In this study, we decorated CT with AW for obtaining CaTiO 3 : α -Ag 2 WO 4 (CT:AW), and investigated the properties of the produced materials, especially their PL properties. The X-ray diffraction peaks of the synthesized microcrystals were well indexed to the orthorhombic phase for all the samples. Two morphologies: cube-like for CT and rod-like for AW were observed by field-emission scanning electron microscopy (FE-SEM). The FE-SEM and transmission electron microscopy (TEM) studies indicated the presence of rod-shaped AW deposited on the surfaces of cube-shaped CT morphology. PL emission of the decorated samples overlaps all the visible region spectra because of the contribution from both the constituent materials that induce maximum emissions in the blue and red regions. The examination of Commission internationale de ĺéclairage (CIE) coordinates confirmed that the decorated samples exhibit favored emission the red wavelength region. [ABSTRACT FROM AUTHOR]

The symbiosis between microorganisms and host arthropods can cause biological, physiological, and reproductive changes in the host population. The present study aimed to survey facultative symbionts of the genera Wolbachia , Arsenophonus , Cardinium , Rickettsia , and Nosema in Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) and Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) in the laboratory and evaluate the influence of infection on the fitness of these hosts. For this purpose, 16S rDNA primers were used to detect these facultative symbionts in the host species, and the hosts' biological and morphological features were evaluated for changes resulting from the infection caused by these microorganisms. The bacterial symbionts studied herein were not detected in the D. saccharalis samples analysed, but the endosymbiont Wolbachia was detected in C. flavipes and altered the biological and morphological aspects of this parasitoid insect. The results of this study may help to elucidate the role of Wolbachia in maintaining the quality of populations/lineages of C. flavipes. [ABSTRACT FROM AUTHOR]

In this work, the impact of the chemical potential of sodium hydroxide concentration was evaluated in the synthesis of titanate-based photocatalysts prepared by the microwave-assisted hydrothermal method. The materials were characterized by techniques that made it possible to unveil their structural, morphological, and electronic properties, corroborating the formation of a heterojunction of sodium titanate (Na 2 Ti 6 O 13) and hydrated hydrogen titanate (H 2 Ti 3 O 7 ·H 2 O). The results demonstrated that the increased chemical potential of NaOH caused an ionic exchange between Na+ and H+ ions, making the H 2 Ti 3 O 7 ·H 2 O phase more stable. The oriented attachment (OA) growth mechanism was predominant, resulting in nanoparticles with nanosheet-like morphology. The photocatalytic efficiency of the materials was tested for the discoloration of Rhodamine B (RhB) and Methylene Blue (MB) dyes. The photocatalyst with the best efficiency showed a half-life time for RhB discoloration of only 5 min and a high capacity of adsorption in the MB medium (∼90% in 10 min). The details of the nanoparticle growth mechanism, the charge transport in the heterojunction, and the stability and reusability of the materials were clarified. • H 2 Ti 3 O 7 ·(H 2 O) /Na 2 Ti 6 O 13 photocatalysts were facilely synthesized. • Low temperature and short time was used for sample preparation. • Influence of sodium on titanate preparation. • The materials possessed highly efficient photocatalytic and adsorption. • The growth of nanosheets is drive by oriented attachment and Ostwald Ripening. [ABSTRACT FROM AUTHOR]

• Composites combining Nd(OH) 3 and ZnO were synthesized. • Synergic effect between Nd(OH) 3 and ZnO favored photocatalytic activity. • 1Nd(OH) 3 -ZnO composite showed high antimicrobial activity against E. coli and S. aureus. • Nd(OH) 3 -ZnO can be used as luminescent materials, photocatalyst and antibacterial agent. Nd(OH) 3 -ZnO composites were synthesized with three content of Neodymium (1, 3 and 5 wt%) and characterized in terms of their structural, morphological, vibrational, optical, surface, photocatalytic and antimicrobial properties. The Nd(OH) 3 -ZnO composites are constituted by ZnO, which showed hexagonal structure, three-dimensional morphology analogous to an arrangement of flowers with hexagonal rods, and the Nd(OH) 3 in the hexagonal phase with irregularly spherical shape. The presence of the Nd(OH) 3 in the composites promoted some structural degree of disorder in the ZnO network as well as interstitial defects and oxygen vacancy, which improved photocatalytic and antimicrobial activity. From the Box-Behnken design and response surface methodology, it was determined that the 1Nd(OH) 3 -ZnO composite showed the highest photocatalytic activity, which was attributed to its higher crystallinity, smaller crystallite size and particle width, band gap energy close to ZnO and lower recombination rate compared to ZnO. Nd(OH) 3 -ZnO composites showed higher antimicrobial activity against E. coli and S. aureus than ZnO pure, evidencing the synergistic effect between Nd(OH) 3 and ZnO in the composites. Therefore, this study highlights the synthesis of Nd(OH) 3 -ZnO composites combining zinc oxide and neodymium hydroxide with excellent photocatalytic and antimicrobial activity, which can be used in different practical applications such as luminescent material, photocatalyst and antimicrobial agent. [ABSTRACT FROM AUTHOR]