Frequency of Tongue Anomalies among Yemeni Children in Dental Clinics

Objective: This study was designed to know the frequency of tongue anomalies and determine their relation with gender.Methods: This study was conducted on five hundreds Yemeni children, (250) boys and (250) girls with an age ranged from 6 -12 years. The sample was collected during the 2nd semester of 2013 from dental clinics, College of Dentistry, University of Sciences & Technology, Sana'a, Yemen. Children were examined with a disposable mouth mirrors, using gloves and gauze pads.Results: Fissured tongue (6.8%) was the most prevalent tongue anomalies, followed by geographic tongue (4.6%), then macroglossia (2.6%), after that ankyloglossia (2.2%), then hairy tongue (0.8%), and finally microglossia (0.4%).Conclusion: The frequency of tongue anomalies among Yemeni children was in boys more than girls. Fissured tongue was the commonest tongue anomaly, while the lowest one was microglossia

Effect of the annealing temperature on the structural and magnetic properties of ZnO nanoparticles

We report on the effect of annealing temperature on the structural and magnetic properties of the pure ZnO nanoparticles (NPs) synthesized using sol–gel route. X-ray diffraction (XRD) patterns confirm the single-phase, a typical wurtzite structure, in all the samples. Crystallite sizes are found to increase with increase in the annealing temperature. The defects and the presence of oxygen vacancy have been estimated through photoluminescence (PL) and micro-Raman spectroscopic studies. These samples exhibit room temperature ferromagnetism (RT-FM) and the saturation magnetization (MS) decreases gradually with increasing the annealing temperature. The ferromagnetic ordering in ZnO NPs is intrinsic and may be induced via surface defect like oxygen vacancy

Photon harvesting and light trapping in pentacene and PTCDI-C13H27 for organic solar cell application

The deep understanding of optical and spectroscopic properties of organic semiconductors is essential for designing the organic photovoltaic solar cells (OSCs) and estimating their prospect performance. In this work, the optoelectronic properties of pentacene and PTCDI-C13H27 conjugated molecules were estimated using density function theory (DFT) calculations. Hence, the parameters of energy gaps, charge transfer (CT), open circuit voltage (VOC), reorganization energy and light harvesting efficiency (LHE) have been extracted using the DFT at B3LYP/6-311G(d,p) level. The results predicted that pentacene and PTCDI-C13H27 molecules possess an efficient broad-band photon harvesting over the visible spectrum with absorption maximum at 643 and 514.5 nm respectively. Moreover, the light trapping inside the pentacene and PTCDI-C13H27 layers integrated in a proposed OSC have been studied using 3D finite difference time domain (FDTD) model. The optimum thickness of the OSC layers were evaluated based on their absorption capability

Electronic structure and energy gaps evaluation of perovskite manganite single crystals using XES and XAS spectroscopy

In this work, the X-ray absorption spectroscopy (XAS), and emission spectra spectroscopy (XES) carried out in synchrotron radiation, were employed to evaluate the electronic structure, and bandgap energy of perovskite manganese: LaSr2Mn2O7, La1.2(Ba, Ca)1.8Mn2O7 and La0.95Ba0.05MnO3 single crystals. Atomic multiple calculations also have been utilized to assess the Jahn-Teller distortion and extracting quantitative details on the ligand metal charge transfer (LMCT). We find that Mn ions possess mixed oxidation states Mn3+/Mn4+ as dominated ground configurations with a small fraction of Mn2+. The trivalent Mn3+ (Mn2O3) exist with high spin (HS) 2p3d4 (e g3 t2 g1). The band edge positions and bandgap energy are remarkably influenced by Alkaline (Ba/Ca) dopant ions as well as by temperature, where, the low temperature causes the bandgap to be significantly narrowing and that has been stated and discussed