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Nanocomposites of CuCr2O4were fabricated by the sol-gel method using copper nitrate and chromium nitrate as precursors (molar ratio of 1:2) under thermal decomposition. The copper nitrate and chromium nitrate sol have been prepared by dissolving the precursors in ethylene glycol, diethyl ether, and citric acid at room temperature. The stable sol was raised to 70°C and the solution turned into high-viscous gel. The gel was converted to xerogel at 135°C for 2 h was calcined in air at different temperatures. The effects of calcinations temperature on the properties of nanocomposite were studied by field-emission scanning electron microscope (FESEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy, and UV–Vis diffuse reflectance spectrum. XRD data of the samples proved the formation of the CuCr2O4nanocomposite at 700°C. FESEM showed that the spherical-like particles have a diameter of 33 nm. Optical spectra of the nanocomposite show a band gaps at 2.19 and 4.66 eV related to band gap transitions of CuCr2O4nanocomposite. [ABSTRACT FROM PUBLISHER]

Nickel catalysts are the most popular for steam reforming, however, they have a number of drawbacks, such as high propensity toward coke formation and intolerance to sulfur. In an effort to improve their behavior, a series of Ni-catalysts supported on pure and La-, Ba-, (La+Ba)- and Ce-doped γ-alumina has been prepared. The doped supports and the catalysts have been extensively characterized. The catalysts performance was evaluated for steam reforming of n-hexadecane pure or doped with dibenzothiophene as surrogate for sulphur-free or commercial diesel, respectively. The undoped catalyst lost its activity after 1.5 h on stream. Doping of the support with La improved the initial catalyst activity. However, this catalyst was completely deactivated after 2 h on stream. Doping with Ba or La+Ba improved the stability of the catalysts. This improvement is attributed to the increase of the dispersion of the nickel phase, the decrease of the support acidity and the increase of Ni-phase reducibility. The best catalyst of the series doped with La+Ba proved to be sulphur tolerant and stable for more than 160 h on stream. Doping of the support with Ce also improved the catalytic performance of the corresponding catalyst, but more work is needed to explain this behavior. [ABSTRACT FROM AUTHOR]

The dielectric constant of aqueous MgCl2solution has been determined in the frequency range 0.2 MHz to 20 GHz at 298 K using the dielectric relaxation spectroscopy method. The behavior is well described according to four Cole-Cole terms whose evolution with composition is analyzed. The static dielectric constant and relaxation times decreases with the increasing aqueous MgCl2solution concentrations. Only one H-bonded water cluster with the aqueous MgCl2solution relaxes is reported during the cutoff relaxation time. A distinct ion–water cooperative interaction is observed, and water molecules perturbed by ion contribution on dielectric constant beyond the first hydration shell are obtained. [ABSTRACT FROM PUBLISHER]

Anatase TiO2 nanoparticles (NPs) with particle size of 10-20 nm were prepared via sol gel technique. The as-synthesized NPs were immerged in vitamin B12 (VB12) solutions with different concentrations. The influences of the solution concentration on photoluminescence and photocatalytic activity of the modified NPs were studied. Fourier transform infrared spectroscopy (FTIR) results demonstrated that TiO2 NPs adsorb VB12 molecules and that a new band is formed at ~2300 cm-1. TheVB12 loading process led to diminishing of the aggregation of NPs and formation of a fibre shape structure. The best photoactivity and PL effect among the modified samples was related to sample 'd'. The optimum processing conditions to achieve this sample was found to be VB12 concentration of 5 g/L. [ABSTRACT FROM AUTHOR]

In this work, thermally stimulated depolarization current (TSDC) and dielectric relaxation spectroscopy (DRS) techniques were performed in complementarities to characterize the dielectric relaxation processes in poly(methylmethacrylate) (PMMA) polymer. Three relaxations were highlighted. Based on correlation between TSDC and DRS data, they were attributed respectively to dipolar β and α relaxations as well as interfacial ρ relaxation. New experimental procedure of fractional polarization was used to investigate space charge trap depth distribution within the band-gap of PMMA. Then the individual peaks were fitted to Bucci–Fieschi model, to evaluate the relaxation parameters. The obtained values were discussed in correlation to those evaluated from DRS data fitted to Havriliak–Negami and Arrhenius models. The various observed peaks in the thermograms are discussed on the basis of space charge polarization. The trap energies were evaluated from the fit to the Bucci–Fuschi model. Similarly other parameters such as relaxation time and charge release are evaluated. [ABSTRACT FROM AUTHOR]

Vitamin B 12 (VB 12 ) was applied to modify TiO 2 nanoparticles (NPs) for the first time. TiO 2 NPs were synthesized via sol–gel method. In the next step, as-synthesized NPs were modified by VB 12 . Fourier transform infrared (FTIR) spectroscopy demonstrated the formation of primary bonds between NPs and VB 12 . Thermogravimetric analysis (TGA) was also utilized to calculate the proportion of NPs to VB 12 . The percentage of VB 12 gained was ~20 wt%. The band gap value decreased from 3.27 (TiO 2 ) to 3.20 eV and the photocatalytic degradation of Rhodamine B (RB) solution diluted in VB 12 –TiO 2 NPs. The photoluminescence (PL) intensity increased from 3 to 6 cd. This is because the total pore volume raised about 18% by modifying TiO 2 NPs; therefore, the photogenerated charge-carrier recombination rate increases by the VB 12 loading. [ABSTRACT FROM AUTHOR]

Commercially available microcrystalline TiO2was doped with silver, ferrous and ferric ion (1.0 mol %) using silver nitrate, ferrous sulfate and ferric nitrate solutions following the liquid impregnation technology. The catalysts prepared were characterised by FESEM, XRD, FTIR, DRS, particle size and micropore analysis. The photocatalytic activity of the prepared catalysts was tested on the degradation of two model dyes, methylene blue (3,7-bis (Dimethylamino)-phenothiazin-5-ium chloride, a cationic thiazine dye) and methyl blue (disodium;4-[4-[[4-(4-sulfonatoanilino)phenyl]-[4-(4-sulfonatophenyl)azaniumylidenecyclohexa-2,5-dien-1-ylidene]methyl]anilino]benzene sulfonate, an anionic triphenyl methane dye) under irradiation by UV and visible light in a batch reactor. The efficiency of the photocatalysts under UV and visible light was compared to ascertain the light range for effective utilization. The catalysts were found to have the anatase crystalline structure and their particle size is in a range of 140-250 nm. In the case of Fe2+doped TiO2and Fe3+doped TiO2,there was a greater shift in the optical absorption towards the visible range. Under UV light, Ag+doped TiO2was the most efficient catalyst and the corresponding decolorization was more than 99% for both the dyes. Under visible light, Fe3+doped TiO2was the most efficient photocatalyst with more than 96% and 90% decolorization for methylene blue and methyl blue, respectively. The kinetics of the reaction under both UV and visible light was investigated using the Langmuir–Hinshelwood pseudo–first-order kinetic model. Kinetic measurements confirmed that, Ag+doped TiO2was most efficient in the UV range, while Fe3+doped TiO2was most efficient in the visible range. [ABSTRACT FROM AUTHOR]

Tuberculosis has increased all over the world. This paper reports the case of a male patient with tuberculous meningitis, spinal tuberculosis (Pott's disease) and severe adverse reactions to antituberculosis drugs. He had skin rash, hepatitis, eosinophilia and fever; all these signs make the diagnosis of DRESS syndrome. This syndrome is caused by a severe hypersensitivity reaction to different drugs. It is usually caused by anti-convulsants, sulfonamides and some antiviral drugs, among other drugs. Anti-tuberculosis drugs can also cause this potentially fatal syndrome. The importance of surveillance for early detection and treatment of adverse drug reactions is emphasized. [ABSTRACT FROM AUTHOR]

The isothermal crystallization kinetics of 4-n-pentyl-4–cyanobiphenyl (5CB) has been studied with Differential Scanning Calorimetry (DSC) and Dielectric Relaxation Spectroscopy (DRS). 5CB is a well characterized material which makes it ideal for a dielectric and thermal comparative study. The effect that isothermal crystallization exerts on the behavior of relaxation processes α and δ by cooling the isotropic liquid below the nematic phase or through the process of cold crystallization by heating it from the supercooled state is explored by comparing the DRS and DSC. Furthermore, by employing the Avrami equation, we compare the ability to probe the crystallization with each technique. [ABSTRACT FROM AUTHOR]

In this study, MgP 2 O 6 :Eu3+ phosphors were successfully synthesized via combustion route and varying the concentration of Eu3+ ion in the host at 0–3.5 mol%. The XRD results of undoped and Eu3+ (2.5 mol%) doped exhibit that the prepared material was obtained in a single phase (Monoclinic phase). The excitation and emission features were also studied and the result indicated that the as-prepared sample can be a prospective candidate for red emitting near-UV LEDs. The mechanism responsible for the quenching effect (decreased luminescence) was obtained to be electric quadrupole-quadrupole interaction. The average life time of optimum molar concentration of Eu3+ (2.5 mol%) doped MgP 2 O 6 phosphor was calculated and obtained to be 3.02 ms. [ABSTRACT FROM AUTHOR]

Pure and Dy(1.15, 2.24, 3.33 and 4.02 at.%)-doped ZnO nanoparticles were prepared by the chemical co-precipitation method. The as prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA-DTA), Raman spectroscopy, UV–Vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) studies. XRD studies confirm both undoped and Dy-doped ZnO nanoparticles reveal wurtzite structure with average grain size in the range of 24–16 nm and are in agreement with TEM analysis. EDS confirms the presence of Dy in Dy-doped ZnO nanoparticles. Raman studies, confirm the wurtzite structure of ZnO nanoparticles besides increase in defects with doping concentration. UV–Vis DRS measurements indicated a blue shift optical band gap with Dy-doping. PL spectrum demonstrated immense enhanced green emission which attributes to the increase in defects concentration. The emissions intensity could be tuned by varying the Dy concentration and excitation wavelength as well for the application of better optoelectronic devices. [ABSTRACT FROM AUTHOR]

ZnO@CdS core-shell nano-structure has been synthesized using zinc acetate dihydrate, and cadmium acetate dihydrate as simple precursors in a water-ethanol matrix without using any surfactant, ligand or chelating agents. The effect of different concentrations of cadmium acetate and sodium sulfide on optical and electronic properties of ZnO@CdS core-shell was investigated. The morphology and structure of the ZnO@CdS core-shell nano-structures have been confirmed by field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) measurements. The results showed that the ZnO@CdS core-shell nano-structure is mixed cubic and hexagonal structures. FESEM results showed the mono-dispersed and uniform size of 39nm. Optical properties were studied by UV-visible diffuse reflectance spectroscopy (DRS) technique and the results showed that band gaps of ZnO@CdS core-shell nanocomposites were red shifted by increasing the cadmium concentration. FTIR spectrum of ZnO@CdS core-shell nano-structure showed a band at 482cm-1 correlated to ZnO bond and a band at 630cm-1 due to the stretching frequency of CdS bond. [ABSTRACT FROM AUTHOR]

A sensitive 2-(4-methoxyphenyl)-1-(naphthalene-1-yl)-4,5-diphenyl-1H-imidazole (MNDI) fluorescent sensor for nanoparticulate ZnO has been designed and synthesized. The nanocrystalline ZnO, Cu-doped ZnO, and Ag-doped ZnO have been synthesised by sol–gel method and characterized by powder X-ray diffraction, scanning electron microscopy(SEM), UV–vis diffuse reflectance, photoluminescence and life time spectral studies. All the synthesized nanoparticles display violet emission due to charge carrier-recombination. The synthesized sensor emission is enhanced by nanocrystalline pristine ZnO but is suppressed by Cu-doped ZnO and Ag-doped ZnO nanoparticles. The suppression of fluorescence is more by copper than by silver doping. [ABSTRACT FROM AUTHOR]

Mixed CuO-ZnO-Cu2O nano-composites have been prepared by a sol–gel route using monoethanolamine/isopropanol solutions and metal acetate precursors which is simple and cost effective. The precursor powders were analyzed by thermogravimetry (TG) and differential thermogravimetry (DTG). X-ray powder diffractometry (XRD), infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM) were used to characterize the structural and the chemical features of the nano-composites. It was observed that the crystal structure changed from ZnO-CuO-Cu2O-Cu with 31.6, 5.5, 24.9, 38 (%w/w) at 350°C calcinations temperature to 42.4, 48.7, 6.1, 2.8 (%w/w) at 550°C calcinations temperature. XRD measurements indicated an increase in the ratio of ZnO-CuO while the ratio of Cu2O-Cu was decreased. The ZnO-CuO-Cu2O-Cu nano-composites with different content ratios were formed. The crystalline characteristics depended primarily on the calcinations temperature. These semiconducting composite oxides have potential applications in electronics and optoelectronics. An average nano-crystallite size of 68 nm was obtained as estimated by Scherrer's equation. The optical properties were also investigated using diffuse reflectance (DRS) spectroscopy. [ABSTRACT FROM PUBLISHER]

Zinc oxide nano-particles were prepared by a sol–gel pyrrolysis technique using zinc acetate as the precursor compound, isopropanol (IP) as solvent and monoethanolamine (MEA) as chelating and structure directing agent. The dried sol treated in different annealing temperatures was analyzedviathermogravimetry analysis (TG-DTG). Zinc oxide nano-particles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (FESEM) techniques and their optical properties were also investigated using diffuse reflectance (DRS) spectroscopy. The results showed that the annealing temperature affected the particle sizes of zinc oxide nano-particles and the weight loss occurred at a peak temperature of 315°C corresponding to formation of zinc oxide. The results indicated that 450°C is the optimum calcination temperature to produce effective zinc oxide nano-particles. The XRD results suggested that the zinc acetate were completely converted to zinc oxide above 350°C. The average crystallite size of the zinc oxide nano-particles was analyzed by XRD and estimated to vary from 54 nm to 65 nm. The results of DRS showed optical band gaps of 3.235, 3.211, and 3.215 eV for zinc oxide nano-particles annealed at 350°C, 450°C, and 550°C, respectively. [ABSTRACT FROM PUBLISHER]

Abstract: This work reports the deposition of platinum (Pt) nanoparticles on the surface of graphene nanosheet by a simple approach, using a microwave-assisted method. The photocatalytic activity has been investigated for hydrogen evolution. The hydrogen evolutions were attributed to graphene, due to its high photoelectron transport properties, and the Pt nanoparticles attached on the surface of graphene sheet, which act as reaction centers for H2 evolution. The “as-prepared” composites were characterized by Brunauer Emmett Teller (BET) surface area measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and UV–vis diffuse reflectance spectra (DRS). This work highlights the potential application of graphene-based materials in the field of energy conversion. [Copyright &y& Elsevier]

Complex dielectric function, alternating current electrical conductivity, electrical modulus and impedance spectra of PEO-LiClO electrolyte films prepared by different methods are investigated over the frequency range of 20 Hz-1 MHz using dielectric relaxation spectroscopy. The effect of preparation methods on the polymer-salt complexation and poly(ethylene oxide) (PEO) crystallinity has been studied by the X-ray diffraction. It has been observed that the ionic conductivity and dielectric relaxation times obey the Arrhenius behaviour. The ionic conductivity of PEO-LiClO electrolyte has been compared with that of PEO-LiClO, PEO-LiClO and PEO-LiClO electrolytes. It is revealed that the logarithmic ionic conductivity of these electrolytes has linear behaviour with salt concentration which is significantly affected by the sample preparation methods. The ionic conductivity of these solid polymer electrolytes increases with the increase of dielectric strength and the decrease of relaxation times associated with ion conduction. [ABSTRACT FROM AUTHOR]

Specialised software for the analysis of qualitative data has been in development for the last thirty years. However, its adoption is far from widespread. Additionally, qualitative research itself is evolving, from projects that utilised small, text-based data sets to those which involve the collection, management, and analysis of enormous quantities of multimedia data or data of multiple types. Software has struggled to keep up with these changes for several reasons: 1. meeting the needs of researchers is complicated by the lack of documentation and critique by those who are implementing software use and 2. audiovisual data is particularly challenging due to the multidimensionality of data and substantial variety in research project aims and output requirements. This article discusses the history of Computer Assisted Qualitative Data AnalysiS (CAQDAS) as it relates to audiovisual data, and introduces the term "fidelity" as a conceptual mechanism to match software tools and researcher needs. Currently available software tools are examined and areas found lacking are highlighted. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1101372

Abstract: Zn0.97−x Al x Cr0.03S (x=0.00, 0.02, 0.04, 0.06, 0.08, 0.10 and 0.12) nanoparticles were synthesized by the chemical co-precipitation method using Ethylene Di-amine Tetra Acetic acid (EDTA) as capping agent. The effect of Al co-dopant on the structural, optical and magnetic properties is discussed on the basis of EDS, SEM, XRD, TEM, SAED, DRS, FTIR, PL, EPR and VSM results. EDS studies indicated the presence of Zn, S, Cr and Al elements in the samples with near stoichiometry. XRD, TEM and SAED studies revealed that samples of all concentrations exhibited cubic structure. The absorption edge in DRS spectra shifted towards higher wavelength with increasing Al concentration indicating a decrease of band gap from 4.05 to 3.85eV. Enhanced photoluminescence was observed with increasing Al concentration up to 4at% and beyond this photoluminescence quenching was observed. FTIR spectral studies indicated that EDTA simply co-exists on the surface of the nanoparticles and acts as the capping agent preventing agglomeration of the nanoparticles. EPR spectral studies indicated that the EPR signal intensity, linewidth and number of spins increased with Al concentration. VSM studies revealed that Al co-doping suppressed the room temperature ferromagnetism in ZnS:Cr nanoparticles. [Copyright &y& Elsevier]

Abstract: Radiation crosslinking of elastomers is an example of the modification of polymers by ionizing radiation. In practice, often parallel both traditional crosslinking (with peroxide) and radiation treatment is applied (Bik et al., 2003, 2004). Elastomers can be irradiated both before and/or after vulcanization products. The aim of this study was to investigate the system of the mixed radiation/peroxide and peroxide/radiation crosslinking of selected elastomers (Engage 8200, HNBR). In particular, attention was directed to the influence of the protective effects of aromatic additives in elastomers (peroxides, thermal- and light stabilizers) on the phenomenon of crosslinking and postradiation oxidation. Aromatic peroxides may undergo modifications during the preirradiation, which affect the subsequent processes of vulcanization. In this way the method of gas chromatography (GC) was applied for determination of hydrogen and oxidation effects, never described before for Engage 8200. Using that approach, radiation efficiency of hydrogen evolution and oxygen absorption efficiency of the polymers has been identified. To describe the phenomena of postradiation oxidation of elastomers, the method of Diffuse Reflection Spectrophotometry (DRS) was also applied. [Copyright &y& Elsevier]

Highlights: [•] The size of these nanoparticles is in the range of ∼10–20nm. [•] B.E., at 780.0 and 796.2eV, corresponding to Co 2p3/2 and Co 2p1/2, respectively. [•] The strong peaks of CO as well as O and confirms the presence of CO in the product. [•] Linearly fitted into two lines with the intercept at 2.28 and 1.57eV. [•] The peak at 2506cm−1 pertaining to Co2 is vibrant by environmental effect. [ABSTRACT FROM AUTHOR]

Highlights: [•] Pt–graphene/TiO2 nanocomposites were synthesized by MAS method. [•] Pt–graphene/TiO2 nanocomposites were used for the degradation of organic Dye under UV/Visible light. [•] Enhanced photocatalytic activity was observed for Pt–graphene/TiO2 nanocomposites. [•] Red shift observed having band gap of 1.8eV in the nanocomposite from (DRS) analysis. [ABSTRACT FROM AUTHOR]

In this paper, a new code structure with ideal in-phase cross-correlation for the Spectral-Amplitude-Coding Optical Code-Division Multiple-Access (SAC-CDMA) system called Vectors Combinatorial (VC) code is proposed. VC code is constructed using Euclidian vectors and a simple algebraic way for any positive integer number based on the relationship between the number of users N and the weight W. We have also studied the performance of OCDMA systems using a newly proposed Direct Recovery Scheme (DRS) under various link parameters. The impact of the detection techniques and data rate effects on the Multi-User Interference (MUI) is reported using a commercial optical systems simulator, Virtual Instrument Photonic (VPI™). The VC code is compared mathematically with other codes which use similar techniques. We analyzed and optimized the data rate, fiber length, and channel spacing in order to reduce the BER effect. A comparison between complementary and DRS techniques for theoretical and simulation results taken from VP I™ is demonstrated. It is verified that, for a high data rate (higher than 2.5 Gb/s), even if dispersion compensated devices are not deployed, the BER can be significantly improved when the VC code with desired parameters are selected using DRS technique. Also, it is found that as the channel spacing width goes from very narrow to wide, the BER decreases and best performance occurs at a spacing bandwidth between 0.8 and 1nm. In addition, we have shown that the proposed new DRS technique utilizing VC code significantly improves the performance compared with the conventional SAC Complementary subtraction technique. [ABSTRACT FROM AUTHOR]

Abstract: Delirium’s characteristic fluctuation in symptom severity complicates the assessment of test–retest reliability of scales using classical analyses, but application of modelling to longitudinal data offers a new approach. We evaluated test–retest reliability of the delirium rating scale (DRS) and delirium rating scale-revised-98 (DRS-R98), two widely used instruments with high validity and inter-rater reliability. Two existing longitudinal datasets for each scale included DSM-IV criteria for delirium diagnosis and repeated measurements using the DRS or DRS-R98. To estimate the reliability coefficients R T and R Λ for each scale we used a macros provided by Dr. Laenen at http://www.ibiostat.be/software/measurement.asp. For each dataset a linear mixed-effects model was fitted to estimate the variance–covariance parameters. A total of 531 cases with between 4 and 9 measurement points across studies including both delirious and non-delirious patients. Comorbid dementia in the datasets varied from 27% to 55%. Overall R T for the DRS were 0.71 and 0.50 and for DRS-R98 0.75 and 0.84. R Λ values for DRS were 0.99 and 0.98 and for DRS-R98 were 0.92 and 0.96. Individual R T measures for DRS-R98 and DRS across visits within studies showed more range than overall values. Our models found high overall reliability for both scales. Multiple factors impact a scale's reliability values including sample size, repeated measurements, patient population, etc in addition to rater variability. [Copyright &y& Elsevier]

Résumé: Le score de risque dystocique (SRD) comprend trois parties : une verticale où le bilan de la femme individualise huit éventualités ; une horizontale, où le bilan de la grossesse identifie sept éventualités, et une centrale de pronostic, subdivisée en trois zones (ű dangereuse Ƈ, ű douteuse Ƈ et ű d’espoir Ƈ). Le SRD est positif s’il existe au moins une croix dans la zone dangereuse et/ou deux croix dans la zone douteuse ; autrement, il est négatif. Le test de validation donne de bons résultats (sensibilité=83,61 % ; spécificité=90,05 % ; valeur prédictive positive=72,34 % ; valeur prédictive négative=94,04 %). L’utilisation du SRD à large échelle permet une identification plus rapide des femmes enceintes à haut risque de dystocie obstétricale. Une orientation à temps de ces dernières vers un centre spécialisé en soins obstétricaux et néonataux contribue à la réduction de la mortalité maternelle et de la mortinatalité. [ABSTRACT FROM AUTHOR]

The effect of the calcination procedure on the decomposition of the [Pt(NH)] complex in a cesium-containing NaX zeolite was studied by thermal decomposition accompanied by mass spectrometry and diffuse reflectance spectroscopy, as well as electron paramagnetic resonance and infrared spectroscopy. The decomposition of the complex took place in two steps. Under oxygen, the [Pt(NH)] complex was first converted into the [Pt(NH)] complex in the first step, with predominant nitrogen release. In the second step, corresponding to the decomposition of the remaining two amine ligands, NO was also formed and adsorbed. Oxygen paramagnetic species were also observed. Under He, the decomposition also occurred in two steps with H release. [ABSTRACT FROM AUTHOR]

Abstract: A microwave assisted chemical precipitation method has been employed for the synthesis of nano zinc oxide rods by reacting zinc nitrate and potassium hydroxide. The amount of potassium hydroxide was adjusted for three different pHs to achieve ZnO nano rods with varying aspect ratio. The mechanism of growth of nano rods is explained briefly. The average crystallite size of the as synthesized samples was analyzed by means of powder XRD pattern and estimated to vary from 25.6nm to 43.1nm. The existence of rods was confirmed using scanning electron microscopy (SEM). The samples were also analyzed using FT-IR. The optical properties of the samples were also studied by means of UV–visible spectra and Room Temperature Photo Luminescence studies. The band gap of the samples was determined from the DRS spectrum. A strong near band emission peaks due to surface defects are observed in the PL spectrum. [Copyright &y& Elsevier]

N-doped TiO samples are claimed to be the most promising among the so-called second-generation photocatalysts, but their success in photocatalysis is still under debate. In this study, N-doped TiO nanocrystals are obtained by a simple, quick, and effortless procedure, starting from titanium alkoxide as the precursor for the sol-gel route, with the N source being either inorganic (NH) or organic (triethylamine, urea). Structural, morphological, and optical characterizations are compared with electron paramagnetic resonance (EPR) data to give an integrated picture of such materials. No literature data on the 'aging' features in the dry state of the fresh calcined samples on the EPR and diffuse reflectance spectra (DRS) measurements are reported. Our N-doped TiO powders show different stabilities of paramagnetic and optical signals. The photocatalytic activity is tested, toward the degradation of ethanol in aqueous media, under both visible and UV irradiation, in this latter case resembling the same trend of the paramagnetic species decay. [ABSTRACT FROM AUTHOR]

Abstract: Zn0.97−x Cu x Cr0.03S (x =0.00, 0.01, 0.02, 0.03, 0.04 and 0.05) nanoparticles were synthesized by chemical co-precipitation method for the first time. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDAX). Diffuse reflectance spectra (DRS) and photoluminescence spectra (PL). EDAX spectra confirmed the presence of Cr and Cu in the samples with expected stoichiometry. XRD patterns showed that dopant atoms of Cr and Cu were incorporated at the Zn sites in the cubic structure without disturbing the original ZnS cubic structure. However, at a concentration of 5at.% the planes corresponding to Cu were observed. This shows the immiscibility of Cu in ZnS for a concentration of 5at.%. Reflectance of Cu co-doped samples decreased with increase in Cu concentration. Photoluminescence for pure ZnS was observed in the blue region. 1at.% Cu doping in ZnS:Cr resulted in a significant enhancement of PL intensity. Higher dopant concentrations resulted in a strong quenching of PL intensity. PL emission peak showed a red shift with increase in Cu content. FTIR studies revealed that the nanoparticles were sterically stabilized by EDTA. Magnetization studies indicated that Cu co-doping enhanced significantly the room temperature ferromagnetism of the samples. [Copyright &y& Elsevier]

Abstract: The drs gene is an apoptosis-inducing tumor suppressor. By using drs-knockout (KO) mouse embryonic fibroblasts (MEFs), we showed that drs is involved in the host defense against viral infection. In drs-KO MEFs infected with vesicular stomatitis virus, the viral replication and protein synthesis were markedly enhanced without the upregulation of the cellular protein synthesis. Phosphorylation of S6K, S6, 4EBP1 and TSC2 proteins was closely correlated with the enhanced viral replication in drs-KO MEFs. Drs protein could associate with stress-inducible GADD34 to form a complex with TSC1/2, which suppresses mTOR activity. These findings indicate that Drs suppresses viral replication via mTOR-dependent pathway. [Copyright &y& Elsevier]

Visible and near-infrared (Vis-NIR, 350–2500 nm) diffuse reflection spectroscopy (DRS) models built from "as-collected" samples of solid cattle manure accurately predict concentrations of moisture and crude ash. Because different organic molecules emit different spectral signatures, variations in livestock diet composition may affect the predictive accuracy of these models. This study investigates how differences in livestock diet composition affect Vis-NIR DRS prediction of moisture and crude ash. Spectral signatures of solid manure samples (n = 216) from eighteen groups of cattle on six different diets were used to calibrate and validate partial least squares (PLS) regression models. Seven groups of PLS models were created and validated. In the first group, two-thirds of all samples were randomly selected as the calibration set and the remaining one-third were used for the validation set. In the remaining six groups, samples were grouped by livestock diet (ration). Each ration in turn was held out of calibrations and then used as a validation set. When predicting crude ash, the fully random calibration model produced a root mean square deviation (RMSD) of 2.5% on a dry basis (db), ratio of standard error of prediction to the root mean squared deviation (RPD) of 3.1, bias of 0.14% (db), and correlation coefficient r 2 of 0.90., When predicting moisture, an RMSD of 1.5% on a wet basis (wb), RPD of 4.3, bias of −0.09% (wb), and r 2 of 0.95 was achieved. Model accuracy and precision were not impaired by exclusion of any single ration from model calibration. [ABSTRACT FROM AUTHOR]

Abstract: We have achieved the preparation of five catalysts with various Co and Mo radial profiles in γ-Al2O3 extrudates and loadings similar to the industrial hydrotreatment catalysts. EDS microanalysis was used for determining the profiles achieved. The catalyst bodies prepared were powdered and characterized using N2 adsorption–desorption, temperature programmed reduction, X-ray powder diffraction, UV–vis diffuse reflectance spectroscopy and NO adsorption. The hydrodesulfurization of thiophene under atmospheric pressure was used as a probe reaction. The selectivity for the butane produced was taken as a measure of the hydrogenation ability of the catalysts. The different procedures inevitably used for the preparation of the different profiles affect somewhat the microscopic characteristics of the catalysts (Co and Mo dispersion, concentration of the coordinatively unsaturated sites, cobalt species formed) and to some extent their intrinsic catalytic behavior (determined in the powdered samples). The catalytic activity of the catalyst bodies depends on the aforementioned microscopic characteristics and the internal mass transfer resistance associated with the location of active phases and pores blocking. The combination of these factors becomes the sample with uniform Co and Mo profiles the most active one. DRS, TPR and XRD results indicated high Co dispersion in this sample. The hydrogenation ability of the CoMo/γ-Al2O3 catalysts is higher over the catalyst bodies than over the powdered samples and enhanced on the catalysts with egg-shell Co profiles. [Copyright &y& Elsevier]

Abstract: MAGIC is a system of two 17m diameter Imaging Atmospheric Cherenkov Telescopes (IACTs) for ground-based astronomy. During many years, starting with the design phase of the first telescope in 2003, the upgrade of the second telescope in 2008 up to now, novel technologies have been developed, commissioned and continuously improved. Most components and subsystems represent nowadays state of the art techniques and are under consideration to be used in future detectors. The large reflector area, together with small diameter, high quantum efficiency (QE) photomultipliers (PMTs) in combination with an improved trigger and readout system permits an analysis threshold of 25GeV, the lowest among current IACTs. MAGIC overlaps in energy with the upper end of current satellite experiments and gives the unique opportunity, for the first time, to cross-calibrate ground based versus satellite born detectors. Some selected techniques used in MAGIC, which are in context with this conference, are presented. [Copyright &y& Elsevier]

Specialised software for the analysis of qualitative data has been in development for the last thirty years. However, its adoption is far from widespread. Additionally, qualitative research itself is evolving, from projects that utilised small, text-based data sets to those which involve the collection, management, and analysis of enormous quantities of multimedia data or data of multiple types. Software has struggled to keep up with these changes for several reasons: 1. meeting the needs of researchers is complicated by the lack of documentation and critique by those who are implementing software use and 2. audiovisual data is particularly challenging due to the multidimensionality of data and substantial variety in research project aims and output requirements. This article discusses the history of Computer Assisted Qualitative Data AnalysiS (CAQDAS) as it relates to audiovisual data, and introduces the term "fidelity" as a conceptual mechanism to match software tools and researcher needs. Currently available software tools are examined and areas found lacking are highlighted. [ABSTRACT FROM AUTHOR]

A translated version of the Mattis Dementia Rating Scale (DRS) into Greek ((DRS-GR) was applied to a sample of Greek population (N = 356) comprising normal middle-aged and elderly subjects (controls), as well as patients suffering from Parkinson's (PD) and Alzheimer's disease (AD) to test its reliability and validity. A well-known dementia screening instrument, the Mini Mental State Examination test (MMSE), and a nonverbal measure of abstract reasoning, the Raven Coloured Progressive Matrices, were employed as measures of DRS-GR concurrent validity. Reliability analysis was satisfactory with Cronbach's alpha reaching 0.82 and item to total correlations yielding high coefficients for most items. DRS-GR scores were influenced by age and education, but not by gender. Correlation between MMSE and the total DRS-GR score was significant in patients and normal controls, but correlation between DRS-GR and RCPM was significant in AD and nondemented PD only. Specificity and sensitivity for dementia screening, calculated on a Receiver Operating Characteristic curve, with a cut-off score the mean value minus two standard deviations, corrected for age and education, was 96% and 80%, respectively. Our preliminary findings show that DRS-GR is a reliable and well-adapted instrument for clinical application in the Greek population. [ABSTRACT FROM AUTHOR]