Dentin is a mesenchymal tissue, and, as such, is based on a collagenous matrix that is reinforced by apatite mineral. Collagen fibrils show piezoelectricity, a phenomenon that is used by piezoresponse force microscopy (PFM) to obtain high-resolution images. We applied PFM to image human dentin with 10-nm resolution, and to test the hypothesis that zones of piezoactivity, indicating the presence...

The reactivity and removal kinetics of arsenite treated with single and mixed mineral systems of kaolinite, montmorillonite and goethite injected with iron sulfide under sulfidicanoxic conditions has been investigated. Using empirical models derived from Freundlich isotherm model, injection of sulfidic-anoxic solution of iron sulfide onto the mixed mineral systems enhanced proton coefficient of...

Several organosulfur compounds are present in the crude oil, and are required to be removed before its processing into transport fuel. For this reason, biodesulfurization of thiophenic compounds has been studied extensively. However, studies on the sulfide compounds are scarce. In this paper, we describe desulfurization of a model sulfidic compound, dibenzyl sulfide (DBS) by an isolated Gordoni...

The results on the effectiveness of five 2D electrical resistivity tomography (ERT) survey profiles for Ag-Pb-Zn, fluorite, and barite exploration Mississippi Valley Type (MVT) magmatic deposits northeast Mexico, are presented. were made in areas with mining activities or mineralization outcrops. Schlumberger, dipole-dipole, Wenner array configurations used measurements. showed that electric ca...

A bacterium that was capable of metabolizing atrazine at very high concentrations (>1,000 ppm) was isolated from a herbicide spill site. The organism was differentiated by observing clearing zones on indicator agar plates containing 1,000 ppm atrazine. Detailed taxonomic studies identified the organism as a Pseudomonas sp., designated ADP, that was dissimilar to currently known species. Pseudom...

The relationship between the mineral component of bone and associated collagen has been a matter of continued dispute. We use transmission electron microscopy (TEM) of cryogenically ion milled sections of fully-mineralized cortical bone to study the spatial and topological relationship between mineral and collagen. We observe that hydroxyapatite (HA) occurs largely as elongated plate-like struc...

This paper presents a review of the rationale for the in vitro mineralization process, preparation methods, and clinical applications of mineralized collagen. The rationale for natural mineralized collagen and the related mineralization process has been investigated for decades. Based on the understanding of natural mineralized collagen and its formation process, many attempts have been made to...

The Sorkheh deposit in northwestern Iran exhibits several readily visible general characteristics of sediment-hosted stratiform copper (SSC) mineralization. It consists of fine-grained disseminated base-metal sulfides within gray sandstones (gray beds, the basal whitish Miocene sandstone and shallow-water) that overlie a thick sequence of red beds (Miocene Upper Red Formation). The host gray be...

introduction: the aim of the present study was to evaluate the biocompatibility of two modified formulations of portland cement (pc) mixed with either titanium oxide or both titanium oxide and calcium chloride. methods and materials: polyethylene tubes were filled with modified pcs or angelus mta as the control; the tubes were then implanted in 28 wistar rats subcutaneously. one tube was left e...