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biomineralization
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A logic for multi-domain authorization considering administrators
, Article 9th IEEE Workshop on Policies for Distributed Systems and Networks, POLICY 2008, Palisades, NY, 2 June 2008 through 4 June 2008 ; 2008 , Pages 189-196 ; 9780769531335 (ISBN) ; Amini, M ; Jalili, R ; Sharif University of Technology
2008
Abstract
In multi-domain environments, authorization policies for each administrative domain are determined by either one administrator or through cooperation of multiple administrators. Proposed logic-based models for multi-domain environments' authorization neither consider an administrator as the legislator of a policy in policies' representation nor specify the domain of a policy explicitly. Considering legislators in policy specification provides the possibility of presenting composite administration and utilizing administrators' characteristics in policy analysis such as conflict resolution. In this paper, we propose the syntax, proof theory, and semantics of a logic in which administrators are...
Bonding, structural and thermodynamic analysis of dissociative adsorption of H3O+ ion onto calcite (10 1 ¯ 4) surface: CPMD and DFT calculations
, Article Journal of Molecular Modeling ; Volume 23, Issue 12 , 2017 ; 16102940 (ISSN) ; Koleini, M. M ; Sharif University of Technology
Abstract
We used density functional theory (DFT) and Car-Parrinello molecular dynamics (CPMD) simulation to investigate the adsorption and bond formation of hydronium ion (H3O+) onto a (10 1 ¯ 4) calcite surface. For surface coverage of 25% to 100%, the nature of H3O+ interaction was explored through electron density and energetics in the context of bond critical points. The adsorbate–adsorbent structure was studied by simulation of pair correlation function. The results revealed that dissociation into water molecule(s) and proton(s) complements H3O+ ion(s) adsorbtion. The H2O molecule adsorbs onto the surface via its O atom, and interacts with surface calcium in a closed-shell mode; the H+ ion makes...
The effect of pore morphology and agarose coating on mechanical properties of tricalcium phosphate scaffolds
, Article International Journal of Applied Ceramic Technology ; Volume 19, Issue 5 , 2022 , Pages 2713-2722 ; 1546542X (ISSN) ; Bagheri, R ; Amirkhani, S ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Three-dimensional biocompatible porous structures can be fabricated using different methods. However, the biological and mechanical behaviors of scaffolds are the center of focus in bone tissue engineering. In this study, tricalcium phosphate scaffolds with similar porosity contents but different pore morphologies were fabricated using two different techniques, namely, the replica method and the pore-forming agent method. The samples fabricated using the pore-forming agent showed more than two times higher compressive and bending strengths and more than three times higher compressive moduli. Furthermore, a thin layer of agarose coating improved the compressive and bending strength of both...
In-vitro evaluation of thermoplastic starch/ beta-tricalcium phosphate nano-biocomposite in bone tissue engineering
, Article Ceramics International ; Volume 47, Issue 11 , 2021 , Pages 15458-15463 ; 02728842 (ISSN) ; Bagheri, R ; Taherimehr, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Thermoplastic starch (TPS), as a natural based polymer, is known to have the capability to be used in biological applications due to its biocompatibility and biodegradability. In this study, mechanical properties of TPS are enhanced by incorporating bioactive β-tricalcium phosphate (β-TCP) particles for bone tissue engineering applications. Starch-based nanocomposites containing 3, 5, and 10 wt% of β-TCP nanoparticles (TT3, TT5, TT10) were made using a co-rotating twin-screw extruder. Dynamic light scattering (DLS) and X-ray diffraction (XRD) techniques were employed to analyze the nanocomposites. Moreover, degradability, swelling degree, and biomineralization in a simulated body fluid (SBF)...
Recent progress in inorganic and composite coatings with bactericidal capability for orthopaedic applications
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 7, Issue 1 , Feb , 2011 , Pages 22-39 ; 15499634 (ISSN) ; Tamjid, E ; Pishbin, F ; Boccaccini, A. R ; Sharif University of Technology
Abstract
This review covers the most recent developments of inorganic and organic-inorganic composite coatings for orthopedic implants, providing the interface with living tissue and with potential for drug delivery to combat infections. Conventional systemic delivery of drugs is an inefficient procedure that may cause toxicity and may require a patient's hospitalization for monitoring. Local delivery of antibiotics and other bioactive molecules maximizes their effect where they are required, reduces potential systemic toxicity and increases timeliness and cost efficiency. In addition, local delivery has broad applications in combating infection-related diseases. Polymeric coatings may present some...
A state-of-the-art review of the fabrication and characteristics of titanium and its alloys for biomedical applications
, Article Bio-Design and Manufacturing ; Volume 5, Issue 2 , 2022 , Pages 371-395 ; 20965524 (ISSN) ; Rezvani Ghomi, E ; Alipour, S ; Ramakrishna, S ; Liana Sukiman, N ; Sharif University of Technology
Springer
2022
Abstract
Abstract: Commercially pure titanium and titanium alloys have been among the most commonly used materials for biomedical applications since the 1950s. Due to the excellent mechanical tribological properties, corrosion resistance, biocompatibility, and antibacterial properties of titanium, it is getting much attention as a biomaterial for implants. Furthermore, titanium promotes osseointegration without any additional adhesives by physically bonding with the living bone at the implant site. These properties are crucial for producing high-strength metallic alloys for biomedical applications. Titanium alloys are manufactured into the three types of α, β, and α + β. The scientific and clinical...