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Zn1 -xMg xO thin films were deposited by sol-gel route on p-type Si (100) and quartz substrates. It is ob-served that the incorporation of Mg and morphological features of the sol-gel derived Zn1 -xMg xO thin films extremely depend upon the selection of doping (Mg) precursor salts. Investigation of different doping precursors such as magnesium acetate, magne-sium chloride and magnesium nitrate have been carried out. Zn1 -xMg xO ( x = 0.15) thin films deposited us-ing each doping source were annealed at 300, 500, 700 and 900 °C in the presence of oxygen for one hour. The results showed that the magnesium nitrate required lower annealing temperature and provided good quality of films, However traces of N were observed in the films. The surface morphology and microstructure of the depos-ited thin films were analyzed by atomic force microscopy. The crystallite dimension, shape and the growth rate were found to be significantly affected by dopant precursors. The chemical compositions were determined by elemen-tal dispersive spectra. The band gap modulation is stud-ied by varying the magnesium content from x = 0.00 to 0.40 for each type of salt for Mg doping. The Zn1 -xMg xO films deposited using magnesium chloride exhib-ited poor band gap modulation and lower quality of mi-crostructure. The films deposited using magnesium ace-tate exhibited minimum defects, good crystallinity and higher band gap modulation. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

• OFC neurons were recorded in a conditioned inhibition procedure. • Neural activity failed to signal the negative value of the inhibitor in isolation. • These results suggest representation of associative structure not value. The orbitofrontal cortex (OFC) is often proposed to function as a value integrator; however, alternative accounts focus on its role in representing associative structures that specify the probability and sensory identity of future outcomes. These two accounts make different predictions about how this area should respond to conditioned inhibitors of reward, since in the former, neural activity should reflect the negative value of the inhibitor, whereas in the latter, it should track the estimated probability of a future reward based on all cues present. Here, we assessed these predictions by recording from small groups of neurons in the lateral OFC of rats during training in a conditioned inhibition design. Rats showed negative summation when the inhibitor was compounded with a novel excitor, suggesting that they learned to respond to the conditioned inhibitor appropriately. Against this backdrop, we found unit and population responses that scaled with expected reward value on excitor + inhibitor compound trials. However, the responses of these neurons did not differentiate between the conditioned inhibitor and a neutral cue when both were presented in isolation. Further, when the ensemble patterns were analyzed, activity to the conditioned inhibitor did not classify according to putative negative value. Instead, it classified with a same-modality neutral cue when presented alone and as a unique item when presented in compound with a novel excitor. This pattern of results supports the notion that OFC encodes a model of the causal structure of the environment rather than either the modality or the value of cues. [ABSTRACT FROM AUTHOR]

We investigate here the strain-induced growth of Cu at 600 °C and its interactions with a thermally grown, 270 nm-thick SiO 2 layer on the Si(111) substrate. Our results show clear evidence of triangular voids and formation of triangular islands on the surface via a void-filling mechanism upon Cu deposition, even on a 270 nm-thick dielectric. Different coordination states, oxidation numbers, and chemical compositions of the Cu-grown film are estimated from the core level X-ray photoelectron spectroscopy (XPS) measurements. We find evidence of different compound phases including an intermediate mixed-state of Cu-O-Si at the interface. Emergence of a mixed Cu-O-Si intermediate state is attributed to the new chemical states of Cu x + , O x , and Si x + observed in the high-resolution XPS spectra. This intermediate state, which is supposed to be highly catalytic, is found in the sample with a concentration as high as ∼41%. Within the Cu-O-Si phase, the atomic percentages of Cu, O, and Si are ∼1, ∼86, and ∼13%, respectively. The electrical measurements carried out on the sample reveal different resistive channels across the film and an overall n-type semiconducting nature with a sheet resistance of the order of 10 6 Ω., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Different dilution levels of tannery treated effluent and their corresponding concentration of chromium (Cr6+) were studied in a petridish culture experiment on seed germination and seedling growth in radish (Raphanus sativus L). The different concentrations of Cr6+ (2, 5 and 10 ppm) and treated tannery effluent (10, 25 and 50%) showed reduction in seedling growth and related enzymatic activities with increase in concentration of Cr6+ in treatments and effluent both. The low concentration of chromium (2 ppm) and effluent dilution (10%) showed significant growth reduction separately. At this concentration of chromium and effluent dilution chlorophyll content, amylase, catalase and protein contents remained unchanged while with increase in Cr6+ concentration (>2ppm) and effluent dilution (> 10%) in treatments showed growth inhibitory effects.