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Tungsten oxide (WO3) doped V2O5·MoO3 thin films deposited on glass substrates using dip coating technique were prepared by a Sol–Gel method. Vanadium pentoxide, Molybdenum oxide and Tungsten oxide powder were used as starting precursors. The influence of different doping percentages of (W) has been investigated in X-ray diffraction, High-resolution transmission electron microscopy and electrical measurement. The structure of the obtained nanocrystals were identify by using X-ray diffraction and transmission electron micrograph. The obtained nanorods have lengths up to 220 nm and width of 15–45 nm. The electrical conductivity applied on the sample under investigation. By increasing tungsten (W) concentration the electrical conductivity was found to be increased and the activation energy decreased. Non-adiabatic SPH was found by analysis the electrical conduction. [ABSTRACT FROM AUTHOR]

Environmental pollution and toxicity have been increasing due to the overuse of chemical fertilisers, which has encouraged nanotechnologists to develop eco‐friendly nano‐biofertilisers. The authors demonstrated the effect of biogenic copper nanoparticles (CuNPs) on the growth of pigeon pea (Cajanus cajan L.). The UV–visible analysis showed absorbance at 615 nm. Nanoparticle tracking and analysis revealed particle concentration of 2.18 × 108 particles/ml, with an average size of 33 nm. Zeta potential was found to be −16.7 mV, which showed stability. X‐ray diffraction pattern depicted the face centred cubic structure of CuNPs; Fourier transform infrared spectroscopy demonstrated the capping due to acidic groups, and transmission electron micrograph showed nanoparticles with size 20–30 nm. The effect of CuNPs (20 ppm) on plant growth was studied, for the absorption of CuNPs by plants on photosynthesis, which was evaluated by measuring chlorophyll a fluorescence using Handy‐Plant Efficiency Analyser. CuNPs treatment showed a remarkable increase in height, root length, fresh and dry weights and performance index of seedlings. The overall growth of plants treated with CuNPs after 4 weeks was recorded. The results revealed that inoculation of CuNPs contribute growth and development of pigeon pea due to growth promoting activity of CuNPs. [ABSTRACT FROM AUTHOR]

The compatible interaction between virulent Hessian fly, Mayetiola destructor (Say), larvae and susceptible wheat, Triticum aestivum L., plants was investigated at the light microscope and ultrastructural levels. During the first day of larval attack at the base of the sheath of the third leaf of a wheat seedling, small punctures of the appropriate size (0.1 µm in diameter) and spacing of the paired larval mandibles were found in the outer wall of epidermal cells. Inside epidermal cells, nuclei and cytoplasmic organelles seemed to be breaking down, and the number and size of cytoplasmic vacuoles had increased. Two to 3 d later, epidermal and mesophyll cells at the base of the third leaf showed signs of becoming nutritive. Nutritive cells were identified by an increase in cytoplasmic staining, increased numbers of cellular organelles (mitochondria, proplastids, Golgi, and rough endoplasmic reticulum), numerous small vacuoles, and an irregularly shaped nucleus. The Hessian fly nutritive tissue probably acts as a sink tissue within the wheat seedling, benefiting the growth of larvae by importing photoassimilates. Breakdown of nutritive cells began soon after they were first observed, indicated by a change in the shape and density of the cell nucleus. Contents of nutritive cells moved through compromised cell walls into adjacent cells that had a more complete breakdown and loss of cytoplasm. Structural changes were not restricted to the third leaf. The sixth leaf, a leaf more recently initiated by the shoot apical meristem that was not directly fed upon by larvae, was found to consist primarily of well-developed epidermal layers, with poorly developed mesophyll cells. The implications of these findings for understanding incompatible interactions between avirulent Hessian fly larvae and R gene-defended plants are briefly discussed. [ABSTRACT FROM AUTHOR]

Abstract: GaAs nanocrystalline thin films containing 7–15nm size crystallites were synthesized by an electrodeposition technique. A thin surface Ga2O3 layer was detected due to atmospheric oxidation of the GaAs nanocrystals. The above films were electrically characterized by the capacitance–voltage studies of the Au/nano-GaAs Schottky junctions. The effect of the nanostructure was fairly realized in the capacitance–voltage characteristics by the observation of capacitance peaks arising due to the trapping of the charge carriers by the surface states. The capacitance–voltage characteristics were recorded both at low and high frequencies of the impressed ac signal in order to identify the effect of the surface states on the behavior of the capacitance of the device. [Copyright &y& Elsevier]

Abstract: A solvent tolerant strain of Enterobacter aerogenes was isolated from soil by cyclohexane enrichment. Presence of cyclohexane (20%) in culture media prolonged the lag phase and caused reduction in biomass. Transmission electron micrographs showed convoluted cell membrane and accumulation of solvent in case of the cells grown in cyclohexane. The Enterobacter isolate was able to grow in the range of organic solvents having log P above 3.2 and also in presence of mercury, thus showing potential for treatment of solvent rich wastes. [Copyright &y& Elsevier]

Transparent silicon oxide thin films were deposited on polyethylene terephthalate substrates by means of reactive sputtering in oxygen and their gas barrier properties were evaluated. The SiOx film sputtered in 10% oxygen/90% argon mixture of inlet gases showed the lowest oxygen transmission rate, and this rate increased with an increase of inlet oxygen concentration. In addition, the oxygen contents of SiOx films increases rapidly within the range of small value of the inlet oxygen gas concentration (0–10%), and gently for oxygen gas concentration larger than 10%. The SiOx films sputtered at high oxygen concentration had more micro-defects than the films prepared at low oxygen concentration. The annealing at 120 °C in vacuum improved the gas barrier properties of the SiOx films sputtered at high oxygen concentration. [Copyright &y& Elsevier]

Shewanella putrefaciens is an important spoilage microorganism in chilled Pacific white shrimp. In order to study the cold adaptation behavior of S. putrefaciens , the growth pattern, fatty acid composition, protein content, cell membrane microstructure and membrane fluidity of the isolated strain QY38 cultured at different temperatures (30 °C, 10 °C, and 4 °C) were studied comparatively. The lag phases of S. putrefaciens QY38 cultured at 30 °C, 10 °C, and 4 °C were 2.95 h, 15.42 h and 62.79 h, respectively. The saturated fatty acid content in the bacterial cell decreased with the decrease in incubation temperature, while the content of palmitoleic acid (C16:1), lauric acid (C12:0), and myristic acid (C14:0) increased. Then the cold adaptation process was studied, and membrane fluidity decreased after moving from 30 °C to 4 °C and increased after a period of adaptation. The differential proteins expressed during cold adaptation process showed that the fatty acid metabolism regulon (FadR) and 3-hydroxyacyl-ACP dehydratases (FabA) were up-regulated during cold acclimation, while 3-oxoacyl-ACP synthase (FabB) and desaturase (Des) were down-regulated. It was hypothesized that in S. putrefaciens QY38, the unsaturated fatty acid was biosynthesized through anaerobic metabolic pathway to recover the membrane fluidity to some extent. • Shewanella putrefaciens is one of the most important specific spoilage microorganisms in chilled white shrimp. • The proportion of C16:1, C12:0, and C14:0 of S. putrefaciens increased at low-temperature conditions. • The membrane fluidity of S. putrefaciens recovered to some extent during cold adaption. • The fatty acid metabolism of S. putrefaciens during cold adaption through anaerobic way was regulated by FadR. • Only fabA (not fabB) of S. putrefaciens was regulated by FadR. [ABSTRACT FROM AUTHOR]