National Television and Historical Architecture: Example of Iran

It is believed that a national television channel should contain national contents in order to have acceptable representation for its own nation through history and culture. Novel aesthetic approach to television besides modern intellect of architecture, as will be argued in this paper, opens a way to compare television with other arts such as architecture. In this paper, following the mentioned argument, Iranian national television and Iranian historical architecture have focused as example. By concentrating on Iranian historical architecture, one of the most influential Iranian architectures was specified and was suggested to Iranian national television staff to consider it in their programs. This article draws a line for a more comprehensive research and makes a foundation for television evaluations based on aesthetic elements as well as national contents. In our future papers, we will introduce a computational based evaluation method to compare Iranian national television programs with Iranian architecture based on aesthetic elements

Characterization and synthesis of silver nanostructures in rare earth activated GeO2-PbO glass matrix using matrix adjustment thermal reduction method

This paper reports matrix adjustment thermal reduction method to synthesize silver nanostructures in Er3+/Yb3+ activated GeO2-PbO glass matrix. The GeO2-PbO glass, the medium of nanoparticle formation, doped with Er2O3, Yb2O3 and AgNO3 was prepared by a melt quenching method. Annealing of the glass for different times was utilized, not only due to thermally reduce Ag+ ions to Ag nanostructures, but also to influence the glassy network. This is because, the glass structural transformation temperature is near to 435 °C and heating at more than this temperature can cause some structural changes in the glass matrix. According to TEM images, samples that tolerate 450 °C annealing temperature for one hour show the formation of basil-like silver nanostructures with a mean length of 54 nm and mean diameter of 13 nm embedded in the glass matrix, whereas with annealing at 450 °C for 5 to 20 h, silver nanoparticles of about 3–4 nm mean diameter size are formed. Annealing for 30 h causes silver nanoparticles to aggregate to form larger particles due to an Oswald ripening process. Observation of the characteristic Ag-NP SPR band at 400–500 nm in the UV-visible absorption spectra confirms the existence of silver nanoparticles. The SPR band widens to longer wavelengths in one hour annealed samples, which relates to the existence of nanostructures with different size or fractal shapes. In addition, an increment in the peak of the SPR band by increasing the duration of annealing indicates the formation of more nanoparticles. Furthermore, the existence of a peak at 470 cm–1 in the FTIR spectra of annealed samples and its absence in the samples not exposed to an annealing process suggests that the glass matrix is polymerized by Pb-O chains during the 450 °C annealing process. This is the main source of different nanostructures because of the dissimilar stabilizing media. The tighter media cap the particles to form small and dense nanoparticles but a loose environment leads to the creation of basil-like particles in the glass matrix

The Effect of Different Mixing Methods on the pH and Solubility of Mineral Trioxide Aggregate and Calcium-Enriched Mixture

Introduction: The aim of this study was to evaluate the effect of different mixing techniques on the pH and solubility of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM). Methods and Materials: Five samples were prepared from each biomaterial with different mixing techniques including hand-, amalgamator- or ultrasonic-mixing and were then placed in pre-weighted plastic tubes to determine their pH values. Each tube was then incubated in 10 mL deionized distilled water for 1 h at 37ºC. An electrode was placed in the fluid in each flask at 24ºC and the pH was recorded. In the next stage, six samples from each mixing technique/material were separately placed in glass bottles containing 50 mL of distilled water at 37ºC for 1 h and were let dry for 1 h at 37ºC. The samples’ weights were measured and recorded twice. The procedure was repeated at 1-, 7- and 21-day intervals. Data were analyzed with the repeated measures ANOVA (for solubility) and two-way ANOVA (for pH) and then the post-hoc Tukey’s test was done. Results: The pH of the materials was not significantly affected by mixing methods (P=0.8 for CEM and P=0.1 for MTA). The solubility of all test groups was within the acceptable range (≤3%). However, the solubility of CEM at 1- and 21-day intervals was significantly different (P=0.03 for 1 day and P=0.001 for 21 days). Different mixing techniques had significant effects on the solubility of MTA at the three time points (P=0.004, 0.003 and 0.002 for 1-, 7- and 21-day intervals, respectively). Conclusion: The pH of biomaterials was not influenced by the mixing technique and their solubility was within the acceptable range

The Effect of Different Mixing Methods on the Flow Rate and Compressive Strength of Mineral Trioxide Aggregate and Calcium-Enriched Mixture

Introduction: Flow rate (FR) and compressive strength (CS) are important properties of endodontic biomaterials that may be affected by various mixing methods. The aim of this experimental study was to evaluate the effect of different mixing methods on these properties of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement. Materials and methods: Hand, amalgamator and ultrasonic techniques were used to mix both biomaterials. Then 0.5 mL of each mixture was placed on a glass slab to measure FR. The second glass slab (100 g) was placed on the samples and 180 sec after the initiation of mixing a 100-g force was applied on it for 10 min. After 10 min, the load was removed, and the minimum and maximum diameters of the sample disks were measured. To measure the CS, 6 sample of each group were placed in steel molds and were then stored in distilled water for 21 h and 21 days. Afterwards, the CS test was performed. Data were analyzed with multi-variant ANOVA and post hoc Tukey tests. The level of significance was set at 0.05. Results: There were significant differences in FR of MTA and CEM cement with different mixing techniques (P<0.05). In the MTA group, none of the mixing techniques exhibited a significant effect on CS (P>0.05); however, in CEM group the CS at 21-h and 21-day intervals was higher with the hand technique (P<0.05). Conclusion: Mixing methods affected the flowability of both biomaterials and compressive strength of CEM cement

Upconversion properties of the Er-doped Y2o3, Bi2o3 and Sb2o3 nanoparticles fabricated by pulsed laser ablation in liquid media

Er-doped Y2O3, Bi2O3 and Sb2O3 nanoparticles are synthesized using pulsed laser ablation in a liquid. Ceramic targets of Y2O3:Er3+, Bi2O3:Er3+ and Sb2O3:Er3+ for ablation process are prepared by standard solid-state reaction technique and ablation is carried out in 5-ml distilled water using nanosecond Q-switched Nd:YAG laser. The morphology and size of the fabricated nanoparticles are evaluated by transmission electron microscopy and the luminescence emission properties of the prepared samples are investigated under different excitation wavelengths

Structural, optical, and physical properties of GeOշ-PbO-BiշO³ glass

The lead bismuth germanate glasses are of growing interest, due to their low cut-off optical phonon energy, high linear and nonlinear refractive index and excellent infrared transmission. Fabrication of metallic nanostructures embedded in glass matrix also attracts many researchers because of their enhancement ability of photoluminescence and optical nonlinearity. However, fabrication of metallic nanostructure other than sphere in glass matrix still is a challenge where met with a very limited success. To achieve the research objectives, the undoped and Er3+/Yb3+ doped germanate based glasses samples were prepared. This thesis reports the preparation of GeO2-PbO-Bi2O3 ternary glass system with and without Er3+/Yb3+ by melt cast-quenching method. All samples are studied by a wide range of characterization techniques which includes their structure, elastic and optical properties. An attempt has been made to add silver nanostructures into the germanate based glasses by thermal reduction of melt-quenched glass in order to study the formation of nanostructures in the vitreous network. In the germanate based glasses system the bismuth atom will be substituted by the lead atom to achieve almost mass independent properties due to their closeness of atomic masses. Structure and physical properties were studied by X-ray diffraction,Fourier transform infra-red (FTIR), density, ultrasonic velocities, UV-Visible absorption, photoluminescence and transmission electron microscopy (TEM). All of the samples were fully amorphous and their density, ultrasonic velocities and elastic moduli are relatively low for high lead content samples. FTIR peaks related to PbO covalent bond and bending Bi-O bond of BiO6 group which are formed when both Pb and Bi act the role of former in glass network, were observed in high lead content samples in contrast with low lead samples. The FTIR data also showed that germanium participated in glass structure with both of four-fold and six-fold coordination in all of samples. The UV-visible absorption of the glasses studied showed highest energy of band-gap for Pb-rich samples and also showed characteristic peaks of Er3+/Yb3+ ions. The photoluminescence spectrum obtained by excitation at wavelengths of highest absorption peaks, showed highest intensities for samples with highest lead content which related to lowest non-radiative relaxation in Pb-rich samples. The GeO2-PbO glass dopped with Er2O3, Yb2O3 and AgNO3 were also prepared by melt quenching method. Annealing of the glass were utilized for thermally reducing of Ag+ ions to metallic silver. The TEM results showed that the annealing process at 450˚C caused the formation of silver nanoparticles of about 3 nm mean diameter size. The samples which were annealed at 400˚C temperature showed the formation of silver nanoplates with mean length size of 60 nm embedded in glass matrix. The UV-Visible absorption also confirmed the existence of metallic silver nanostructure. The FTIR shows peaks at 470 cm-1 for 450˚C annealed samples, in contrast with 400˚C annealed samples, which suggest the existence of Pb-O chains in the germanate glass network. This is the main source of difference in formation of various nano structures due to different stabilizing medium and better physical isolation of glass matrix in 450˚C annealed samples

Ultrasonic and optical properties and emission of Er3+/Yb3+ doped lead bismuth-germanate glass affected by Bi+/Bi2+ ions

Rare earth doped heavy metal oxide glasses instead of silicates are interesting research area, especially, for their potential application in optoelectronics. In addition, contribution of different bismuth ionization states in photoluminescence spectra is still an open question. In this research work, [GeO2](60)-[PbO](40-x)-[1/2Bi(2)O(3)](x), glass hosts where x=0, 10, 20, 30, and 40 mol% and 0.5 wt% of Er2O3 and 1.5 wt% of Yb2O3 as doping agents were studied. The activated heavy metal oxide glass samples were synthesized by conventional melt quenching method. The optical properties were studied by refractive index, UV-visible absorption and photoluminescence (PL) measurements, and explained in terms of the Judd-Ofelt theory. The glass was also studied by ultrasonic measurements and showed that the velocity of sound is lower in Pb-rich samples. Our results also, showed that emission intensities are higher in host glasses with lower sound velocities, which is attributed mainly to multiphonon relaxation. In addition, variation of PL intensities with increase of bismuth composition was related not only to the variation of Debye temperature and refractive index; but also, to the increase of Omega(6) in Pb-rich samples due to the ligand field and existence of Bi2+/Bi+ ions in Bi-rich glasses. (C) 2013 Elsevier B.V. All rights reserved

Hydrothermal synthesis of goethite (alpha-FeOOH) nanorods in the presence of ethylenediamine:thiourea

Goethite (alpha-FeOOH) nanorods were synthesized via the hydrothermal method with the assistance of coordinating ligands, i.e. ethylenediamine and thiourea. The homogeneity of the nanorod size distribution increased and the propensity to agglomerate decreased when ethylenediamine and thiourea were used in conjunction; contrary to goethite synthesis in the presence of a single ligand. The type and mode of structure-directing plays a critical role in the morphology of the final products. When using thiourea only or in combination with ethylenediamine, nanorods and nanoparticles of various morphologies were formed. Conversely, when exclusively using ethylenediamine, in addition to the nanorods, fine needles with a significantly smaller diameter were discernible. With all combinations, structurally uniform alpha-FeOOH nanorods were formed. This improved nanorod formation in the presence of both ligands might be attributed to a more ordered alignment and regular conformation of ethylenediamine molecules in the presence of thiourea and thus less susceptibility to thermal perturbations. Finally, higher concentrations of ligand influence the final product and increases particle aggregation

Enhancement of 1536 nm emission of Er doped ZnO nanopowder by Ag doping

Er, Er-Ag and Er-Mg co-doped ZnO nanopowders were prepared by wet chemical precipitation method. The structure and morphology of the prepared samples were studied by XRD and SEM, respectively. The effect of Ag and Mg on visible and IR emission properties of Er doped ZnO nanopowders have been systematically investigated. We found that Mg did not change the visible and IR emission properties of Er doped ZnO nanopowders. But, addition of Ag drastically decreases the visible emission and enhances the IR emission at 1536 nm. (C) 2014 Elsevier B.V. All rights reserved

CCL5 rs2107538 Polymorphism Increased the Risk of Tuberculosis in a Sample of Iranian Population

Cysteine-cysteine chemokine ligand 5 (CCL5) with immunoregulatory and inflammatory activities has an important role in granuloma formations that activates and stimulates T-cells and macrophages. Cysteine-cysteine chemokine receptor 5 (CCR5) is a chemokine receptor, which is important for migration of immune cells to site of infection. In the present study we investigated the possible association between CCL5 –403G/A (rs2107538), CCL5 –28C/G (rs2280788) and CCR5 Δ32 polymorphisms and pulmonary tuberculosis (PTB) in an Iranian population. This case-control study was performed on 160 patients with pulmonary tuberculosis and 160 unrelated healthy subjects. The CCL5 –403G/A, CCL5 –28C/G and CCR5 Δ32 polymorphisms were genotyped by allele-specific polymerase chain reaction (AS-PCR), tetra amplification refractory mutation system polymerase chain reaction (T-ARMS PCR) and PCR, respectively. Our results showed that GA as well as GA+AA genotypes of CCL5 –403G/A (rs2107538) increased the risk of PTB in comparison with GG genotype (OR=1.70, 95% CI=1.03–2.81, P=0.038 and OR=1.64, 95% CI=1.00–2.68, P=0.049, respectively). No significant association was found between CCL5 –28C/G as well as CCR5 Δ32 polymorphism and PTB risk. In conclusion, our findings proposed that CCL5 –403G>A polymorphism may be a risk factor for susceptibility to PTB in our population. Larger sample sizes with different ethnicities are required to validate our findings