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This work presents the influence of dominated electronic energy loss over nuclear energy loss induced by swift heavy ion (SHI) irradiation on the physico-chemical, optical and other properties of RF grown zirconium oxide (ZrO 2) thin films. For this purpose, thin films of ZrO 2 grown on glass substrate were irradiated by 150 MeV Fe11+ ions with a range of fluence from 2E12 to 5E13 ions/cm2 to understand the mechanism of induced modifications and defects generation. The XRD results confirmed that the virgin and irradiated ZrO 2 thin films were crystalline in nature with monoclinic and tetragonal structure. The crystallite size varied from 19.93 nm to 46.43 nm with varying ion fluence. Strain, dislocation density and stacking fault were used to investigate the changes in structural parameters. Tauc's plot method was employed for the quantitative evaluation of optical energy band gap (E g) that exist in the range of 4.45–4.62 eV. The transmittance (%) of the virgin and Fe11+ ions irradiated samples was determined in the range of 35.69–66.09% using UV–Vis. spectroscopy. Further, the refractive index was determined using different methods significantly depends on the optical band gap. The broad PL emission peaks were obtained at 375 nm and 440 nm with the excitation wavelength (λ ex.) of 300 nm. The variation in PL intensity with increasing ion fluence was attributed to the creation or annihilation of primary or complex defects. FTIR spectroscopy was employed for the analysis of chemical modifications in vibrational bonds of samples and the band obtained 660 cm−1was assigned to the asymmetrically coupled Zr–O–Zr stretching which presents the strong vibration in samples. The band intensity increased up to the fluence 5E12 ions/cm2 and decreased at a higher fluence of 1E13 ions/cm2. Rutherford backscattering spectroscopy technique was used to determine the thickness (165 nm) of the samples. [ABSTRACT FROM AUTHOR]

Titanium dioxide thin films were deposited by RF Sputtering technique on Silicon (100) and ITO substrates followed by annealing at 500 °C for 6 h. The synthesized samples were irradiated with Ti9+ heavy ions of energy 120 MeV at various fluences. The strain, stress and crystallite size were calculated by analysing the data of X-ray diffraction (XRD) patterns. The increase in crystallite size was observed from XRD analyses. Modifications in the surface morphology, surface roughness, RMS roughness and grain size distribution were investigated using atomic force microscopy (AFM). Variation in optical energy band gap was observed by Tauc's relation, which shows decreasing trend with increases in fluence (3.91 eV–3.58 eV). Urbach energy and extinction coefficient were also determined in Uv–Visible characterization. Raman spectroscopy was used to identify the crystal phases and chemical structure of virgin and irradiated TiO 2 thin film samples. The statistics of oxygen bonding to the metal ions and information about phase composition in the material was estimated by the FTIR study. Furthermore, the Rutherford backscattering (RBS) experiment was carried out to confirm the film thickness and presence of Ti in the samples. Herein disorder in the structure has been introduced through irradiation leading to improvement in texturing and crystallization at different irradiation fluence. • Thin films were deposited by RF sputtering deposition technique. • Optical bandgap of the films was decreased with increasing of ion fluence. • Thickness of thin films was observed to decrease with increasing of ion fluence. • Increase in crystallite size marked improvement in crystallinity of TiO 2 thin films. [ABSTRACT FROM AUTHOR]

Low dimensional copper wires have gained a lot of interest in the field of device fabrication due to their interesting properties, low synthesis cost and many potential applications. In the present work, effects of γ-radiation exposure on physico-chemical and electrical properties of Cu microwires fabricated by electrochemical deposition in the track-etch membrane were studied. The synthesized Cu microwires were exposed using γ-radiation from a 60 Co source at four different doses of 30, 80, 130 and 180 kGy respectively. The morphology of the pristine and γ-radiation exposed Cu microwires were characterized using Scanning Electron Microscopy. The X-ray diffraction spectra results confirmed the face centered cubic crystal structure for pristine and γ-radiation exposed microwires. Microwire crystallite size was determined using the Scherrer equation and found to increase from 39 to 50 nm with increase in gamma doses. The I-V measurements indicated that the resistance of the microwires increased with increasing gamma dose, suggesting that exposure to γ-radiation increases the reflection from the grain boundaries and induces defects and oxygen impurities in the wires that hinder the mobility of the electrons resulting into decrease in conductivity. [ABSTRACT FROM AUTHOR]

Despite the long history of application of bioinoculants for improving crop productivity, very little information is available on their impact on native microbial communities in crops' rhizosphere. The present study compares the effects of a microbial consortium comprising of Bacillus megaterium , Pseudomonas fluorescens and Trichoderma harzianum , with that of two commonly used chemical fertilizers, on microbial population in Cajanus cajan 's rhizosphere using cultivation-dependent (enumeration) and –independent (denaturing gradient gel electrophoresis, DGGE) methods at both DNA and RNA levels. The bioinoculants' application demonstrated stimulatory effects on rhizospheric microflora of phosphate solubilizing bacteria (2.5- fold), Pseudomonas spp. (1.9- fold), nitrogen fixing bacteria (1.2- fold) and fungi (1.6- fold), which was better than that of chemical fertilizers, rendering the consortium to be safe for release in agricultural fields. The qualitative profiling of microbial communities, based on DGGE, exhibited significant changes in treated rhizosphere samples as compared to the control, indicating the noticeable impact of bioinoculants. The study stresses upon the significance of beneficial role of the bioinoculants on crop productivity, which results due to their interaction with native rhizospheric microbial community. [ABSTRACT FROM AUTHOR]

Highlights: [•] Monitoring of non-target effects of bioinoculants in Cajanus cajan's rhizosphere. [•] Individual as well as combination of bioinoculants employed. [•] Cultivation-dependent and -independent approaches to target microorganisms. [•] Increased abundance of PGPR observed in treated plants. [•] Non-target effects evident by ARISA profiles of treated and control plants. [Copyright &y& Elsevier]

[Display omitted] • PbSe nanowires were synthesized by template assisted electrodeposition and irradiated with 120 MeV Au9+ ions. • SEM micrographs confirmed uniform diameter and vertically aligned geometry of nanowires. • Crystal structure parameters calculated using Scherrer and W-H analysis. • Optical and electrical properties tuned by irradiation. • Gold ion irradiated in PbSe displayed SCLC conducting behavior. Nanowires have attracted widespread attention as a result of breakthrough in nanotechnology due to their new features and potential applications. Lead selenide (PbSe) nanowires have acquired a lot of interest recently because of their exceptional performance and wide range of applications. Electrochemical deposition was used to create arranged PbSe nanowires in polycarbonate templates. Here, the effects of 120 MeV Au9+ swift heavy ion irradiation at fluence ranging from 1 × 109 to 1 × 1012 ions/cm2 on the morphology, crystalline structure, optical and electrical properties were investigated. In the Ion Distribution and Quick Calculation of Damage mode, the TRIM (Transport of Ions in Matter) simulation was employed, and the damage was computed using quick statistical estimates based on the Kinchin-Pease formalism. The primitive and ion irradiated nanowires were characterized by X-ray diffraction, Scanning electron microscopy, Raman spectroscopy, UV–Visible spectroscopy and Current-Voltage characteristics. The results of Raman spectroscopy and X-ray diffraction imply that irradiated nanowires with minimal strain retain their crystallinity. The irradiation has shown strong impact on the optical constants like optical band gap, refractive index, high frequency and static dielectric constant and electron effective mass with no morphological change. At room temperature, the results of electrical properties studies for both primitive and irradiated nanowires are also provided. Our findings encourage the employment of nanowires in the future for photonic and electronic applications. [ABSTRACT FROM AUTHOR]

Abstract: An improved protocol for extraction of prokaryotic mRNA from soil samples was developed by modifying the extraction procedure to obtain higher yields of mRNA and to reduce co-extraction of humic acids. The modified protocol was found to be more robust and efficient compared to the original protocol by Griffiths et al. (2000) without compromising with the quality and quantity of RNA. [Copyright &y& Elsevier]

In the present study, tungsten oxide (WO 3) thin films were grown on glass and silicon substrates using RF sputtering method and thin films were annealed at 550 °C. The prepared WO 3 thin films were exposed through gamma irradiation by varying doses at 100, 200, 300, 400 and 500 kGy. The modification in optical, structural, morphological and chemical properties of WO 3 thin films before and after gamma irradiation doses were observed from UV-Vis, Photoluminescence (PL) and Raman spectroscopy, Fourier Transform spectroscopy (FTIR), Atomic Force Microscopy (AFM), X-ray diffraction (XRD), Rutherford backscattering (RBS) and X-ray photoelectron spectroscopy (XPS). The grain size after gamma irradiation reduced from 6.56 nm to 3.40 nm. The Raman spectroscopy reveals the monoclinic phase of tungsten oxide thin films after gamma irradiation. XRD pattern shows the variation in crystallite size from 7.2 nm to 33.8 nm. The optical band gap of pristine and gamma irradiated thin films was observed from UV-Vis spectroscopy. The functional groups were confirmed by FTIR spectroscopy. PL emission peaks were observed at 415 nm and 475 nm for pristine and gamma irradiated thin films at excitation wavelength of 380 nm. The XPS study reveals the presence of W and O atoms in pristine and gamma irradiated WO 3 thin films. • WO 3 thin films were grown by RF sputtering method. • WO 3 thin films were exposed to gamma irradiation at different doses • Reduction in the optical band gap of WO 3 thin films after gamma irradiation was observed. • The crystallite size was found to be increased after gamma irradiation. • XPS shows shifting of the peak with gamma dose. [ABSTRACT FROM AUTHOR]

Abstract: The use of needle biopsies in basic research is increasing, and our study provides a comprehensive analysis of their adequacy in genomic and proteomic studies of kidney cancer. Frozen clear cell renal cell carcinoma (ccRCC) needle core biopsies and sections from core biopsies embedded in optimal cutting temperature (OCT) compound were used to extract DNA, RNA and protein. Their integrity was determined using genomic and proteomic analyses. VHL mutation testing was performed on ccRCC biopsies and corresponding tumors using bulk and laser capture microdissection (LCM) extractions for comparison. Adequate amounts of good quality DNA (5.8–13.3μg/whole core, 0.6–2.7μg/20 sections), RNA (2.9–11.9μg/whole core, 0.5–1.3μg/20 sections) and protein (137.4–444μg/whole core, 39.9–74.1μg/20 sections) were obtained from whole core and frozen sections of ccRCC needle biopsies, respectively. We observed VHL sequence mutations in 75% of ccRCC tumors and, in most cases, the same mutations were detected in both tumors and corresponding biopsies. Mutations observed by bulk extractions from tumors and biopsies were also detected by LCM without significant differences between both methodologies. ccRCC needle biopsies provide ample material for genomic and proteomic studies of kidney cancer. They are good representatives of their corresponding tumors for VHL mutation detection using both bulk and LCM extractions. LCM does not increase sensitivity of VHL mutation detection. [Copyright &y& Elsevier]