Ultrastructural analysis of submandibular salivary calculus in combination with X-ray microanalysis

Introduction: Sialolithiasis is one of the common diseases of the salivary glands. It was speculated that, in the process of calculi formation, degenerative substances are emitted by saliva and calcification occurs around these substances, and finally calculi are formed. However, the exact mechanism of the formation of calculi is still a matter of debate. The aim of this study: To analyze seven stones ultrastructurally to determine their development mechanism in the submandibular salivary glands. Matherials and methods: To study the morphology (the central and peripheral parts of the submandibular sialolithiasis - n=7) we used a VEGA TESCAN TS 5130MM scanning electron microscope equipped with an Oxford Instruments energy-dispersive x-ray (EDS) system. Results: The study revealed the presence of numerous microstructures of different shapes (nodular, laminar, reticular, microgranular, and multinodular) and variable size arranged in a haphazard fashion. X-ray microanalysis disclosed the component elements in the calculi to be C, Ca, P, Mg, S, Na. The main constituents were Ca and P - in central vs. peripheral parts: 2.5 ± 0.9 vs. 0.8 ± 0.2 (p=0.028) and 2.2 ± 0.7 vs. 0.63 ±0.15 (p=0.02). The major crystals were whitlockite and brushite in central parts of submandibular salivary stone and hydroxyapatite in the peripheral parts. Conclusions: The diverse microstructures encountered strongly suggest that different mechanisms of mineralization occur during growth and development of the sialoliths. High calcium and phosphorous content in the food may be attributed to one of the reasons for the formation of sialoliths

Nanostructures Of Metal Oxides

This chapter focuses on the description of nanostructured metal oxides representing the most common, diverse, and richest class of materials in terms of electronic structure and structural, chemical, and physical properties. Among such properties one can mention electrical, optical, optoelectronic, magnetic, thermal, photoelectrochemical (PEC), photovoltaic, mechanical, and catalytic ones. In this chapter nanostructures based on TiO2, Al2O3, ZnO, SnO2, and CuO are reviewed. These nanomaterials with controlled composition, surface terminations, and crystalline structures are important for furture applications in novel devices. Their properties and surface effects due to nanosized dimensions will also be discussed

Nanomotoren aus Titandioxid - Nanoröhrchen für Bio-Anwendungen (TiNaTEng) : Laufzeit des Vorhabens: 01.10.2013-30.09.2015

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Optical reflectance studies of highly specular anisotropic nanoporous (111) InP membrane

High-precision optical angular reflectance measurements are reported for a specular anisotropic nanoporous (111) InP membrane prepared by doping-assisted wet-electrochemical etching. The membrane surface morphology was investigated using scanning electron microscope imaging and revealed a quasi-uniform and self-organized nanoporous network consisting of semiconductor \u27islands\u27 in the sub-wavelength regime. The optical response of the nanoporous InP surface was studied at 405 nm (740 THz; UV), 633 nm (474 THz; VIS) and 1064 nm (282 THz; NIR), and exhibited a retention of basic macro-dielectric properties. Refractive index determinations demonstrate an optical anisotropy for the membrane which is strongly dependent on the wavelength of incident light, and exhibits an interesting inversion (positive anisotropy to negative) between 405 and 633 nm. The inversion of optical anisotropy is attributed to a strongly reduced \u27metallic\u27 behaviour in the membrane when subject to above-bandgap illumination. For the simplest case of sub-bandgap incident irradiation, the optical properties of the nanoporous InP sample are analysed in terms of an effective refractive index neff and compared to effective media approximations

Effect of heavy noble gas ion irradiation on terahertz emission efficiency of InP (100) and (111) crystal planes

Emission of terahertz (THz) electromagnetic radiation from heavily-doped (5x10 to the power of 18 cm -3) and (111) InP bulk materials and nanoporous honeycomb membranes, irradiated with heavy noble gas (Kr and Xe) ions is presented

Photoinduced modification of surface states in nanoporous InP

Porous honeycombs of n-type InP were investigated by terahertz time-domain and x-ray photoemission spectroscopies. After photoexcitation the dark conductivity was found to increase quasi-irreversibly, recovering only after several hours in air. The calculated electron density for different surface pinning energies suggests that photoexcitation may reduce the density of surface states. © 2012 American Institute of Physics