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The present paper reports optical and electrical properties of undoped and Cr3+ doped CoWO4 nanomaterials. The samples were successfully prepared at room temperature (RT) by simple co-precipitation method and at heat treated at 600 °C for good crystallization. The samples were carefully characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM). The room temperature optical properties were analyzed by UV–visible diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy. The XRD pattern reveals that the Cr3+ doped CoWO4 samples shows single phase formation with wolframite monoclinic structure. SEM micrograph reveals that agglomerated round shaped particle in surface of the samples. The energy band gap value of the CoWO4 nanomaterials decreased with increasing the Cr3+ concentration. The intrinsic emission of CoWO4 nanomaterials were observed with excitation of 210 nm. The Cr3+ incorporation in CoWO4 lattice have not altered the structure of emission spectra other than slight increase in emission intensity. The variation of dielectric constant with frequency and temperature has been studied. Moreover, the dielectric constant of the doped samples was higher than that of the CoWO4 ceramics. The ac conductivity studies has been studied and Jonscher's power law has been used to calculate the DC conductivity and frequency exponential factor (n) for all the samples. [ABSTRACT FROM AUTHOR]

Maize (Zea mays L.) is an important cereal crop grown in arid and semiarid regions of the world. During the reproductive phase, it is more frequently exposed to drought stress, resulting in lower grain yield due to oxidative damage. Selenium and zinc oxide nanoparticles possess inherent antioxidant properties that can alleviate drought-induced oxidative stress by the catalytic scavenging of reactive oxygen species, thereby protecting maize photosynthesis and grain yield. However, the effect of zinc selenide quantum dots (ZnSe QDs) under drought stress was not been quantified. Hence, the aim of this study was to quantify the (i) toxicity potential of ZnSe QDs and (ii) drought mitigation potential of ZnSe QDs by assessing the transpiration rate, photosynthetic rate, oxidant production, antioxidant enzyme activity and seed yield of maize under limited soil moisture levels. Toxicity experiments were carried out with 0 mg L−1 to 500 mg L−1 of ZnSe QDs on earthworms and azolla. The results showed that up to 20 mg L−1, the growth rates of earthworms and azolla were not affected. The dry-down experiment was conducted with three treatments: foliar spray of (i) water, (ii) ZnSe QDs (20 mg L−1), and (iii) combined zinc sulfate (10 mg L−1) and sodium selenate (10 mg L−1). ZnSe or Se applications under drying soil reduced the transpiration rate compared to water spray by partially closing the stomata. ZnSe application at 20 mg L−1 at the tasselling stage significantly increased the photosynthetic rate (25%) by increasing catalase (98%) and peroxidase (85%) enzyme activity and decreased the hydrogen peroxide (23%) content compared to water spray, indicating that premature leaf senescence was delayed under rainfed conditions. ZnSe spray increased seed yield (26%) over water spray by increasing the number of seeds cob-1 (42%). The study concluded that foliar application of ZnSe (20 mg L−1) could decrease drought-induced effects in maize.

Lectins are renowned for recognizing specific carbohydrates, but there is evidence that they can bind to other endogenous ligands. Therefore, lectin can be used as a carrier to recognize glycoconjugates on the cell surface. The anticancer, antibacterial, and immunomodulatory properties of some lectins are established. Metal nanoparticles (MNPs) have been used in various fields recently, but their documented toxicity has raised questions about their suitability for biomedical uses. The advantages of MNPs can be realized if we deliver the NPs to the site of action; as a result, NPs may achieve greater therapeutic efficiency at lower doses with less toxicity. The use of carbohydrate specificity by lectin MNPs conjugates for diagnostics and therapeutics was addressed. The review summarised the multidimensional application of lectins and described their potential for delivery of MNPs in future drug development.

The spectroscopic studies on the conformation and orientation of membrane-incorporated FomA, the major outer membrane protein of Fusobacterium nucleatum and characterization of lipid-protein interactions with FomA are described. The stoichiometric results for the lipid-protein interaction from EPR revealed that FomA is not trimeric in membranes of diC(14:0) phosphatidylcholine and is consistent with a monomeric [beta]-barrel of 14-16 strands.

The EPR spectroscopy technique is employed to study the stoichiometry and selectivity of the lipid-protein interactions on the incorporation of the outer membrane protein, OmpG in the lipid membranes. The stoichiometry of the motionally restricted lipids is shown to increase linearly with the number of [beta]-strands.

Here, we focus on the concentration of six heavy metals (Cd, Cr, Cu, Fe, Pb, and Zn) in the road dust collected from Tiruchirappalli city, one of the cleanest Tier II cities in South India. Five metals were detected in the road dust, except for Cd that was below measurable limit in all 22 dust samples (15 from the urban city and 7 from the sub-urban city). The mean metal concentration in the road dust collected in Tiruchirappalli city was in the order: Fe (506.39 μg/g) > Zn (47.08 μg/g) > Cu (11.84 μg/g) > Cr (11.47 μg/g) > Pb (0.24 μg/g). The metal levels were higher in outer city compared with inner city due to the increased industrial activities on the outskirts of the city and the reduced cleaning routine. Using principal component analysis (PCA) and hierarchical cluster analysis (HCA), the metal sources were found to be a mix of both natural and anthropogenic activities. Various pollution valuation indices viz., geoaccumulation index, pollution load index, contamination degree, potential ecological risk, health hazard quotient, and carcinogenic risk (2.5 x 10-7), revealed that Tiruchirappalli city falls in the unpolluted category. Also, an increasing trend in the metal pollution is observed in the industrial zones due to the heavy traffic and metal processing activities in the region. For now, the status of metal pollution in Tiruchirappalli is safe, but continuous monitoring is crucial to sustain the unpolluted status.