Search results for "Repair"

Antibacterial Properties of Nanoparticles in Dental Restorative Materials. A Systematic Review and Meta-Analysis

2020

Background and Objectives: Nanotechnology has become a significant area of research focused mainly on increasing the antibacterial and mechanical properties of dental materials. The aim of the present systematic review and meta-analysis was to examine and quantitatively analyze the current evidence for the addition of different nanoparticles into dental restorative materials, to determine whether their incorporation increases the antibacterial/antimicrobial properties of the materials. Materials and Methods: A literature search was performed in the Pubmed, Scopus, and Embase databases, up to December 2018, following PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) …

Metal ions modify DNA-protecting and mutagen-scavenging capacities of the AV-153 1,4-dihydropyridine.

2019

Abstract 1,4-Dihydropyridines (1,4-DHP) possess important biochemical and pharmacological properties, including antioxidant and antimutagenic activities. AV-153-Na, an antimutagenic and DNA-repair enhancing compound was shown to interact with DNA by intercalation. Here we studied DNA binding of several AV-153 salts to evaluate the impact of AV-153 modifications on its DNA binding capacity, the ability to scavenge the peroxynitrite, to protect HeLa and B-cells cells against DNA damage. Affinity of the AV-153 salts to DNA measured by a fluorescence assay was dependent on the metal ion forming a salt in position 4 of the 1,4-DHP, and it decreased as follows: Mg > Na > Ca > Li > Rb > K. AV-153-…

DNA-binding studies of AV-153, an antimutagenic and DNA repair-stimulating derivative of 1,4-dihydropiridine.

2014

Abstract The ability to intercalate between DNA strands determines the cytotoxic activity of numerous anticancer drugs. Strikingly, intercalating activity was also reported for some compounds considered to be antimutagenic. The aim of this study was to determine the mode of interaction of DNA with the antimutagenic and DNA repair-stimulating dihydropyridine (DHP) AV-153. DNA and AV-153 interactions were studied by means of UV/VIS spectroscopy, fluorimetry and infrared spectroscopy. Compound AV-153 is a 1,4 dihydropyridine with ethoxycarbonyl groups in positions 3 and 5. Computer modeling of AV-153 and DNA interactions suggested an ability of the compound to dock between DNA strands at a sin…

Combinations of discourse markers with repairs and repetitions in English, French and Spanish

2020

Abstract Discourse markers have a central role in planning and repairing processes of speech production. They relate with fluency and disfluency phenomena such as pauses, repetitions and reformulations. Their polyfunctionality is challenging and few form-function mappings are stable cross-linguistically. This study combines a functional and a structural approach to discourse markers and their combination with and within repetitions and self-repairs in native English, French and Spanish, in order to establish the inter-relation between these three fluency-related devices and to find potentially universal patterns of use. Qualitative coding and quantitative analyses of categories of markers a…

Seliciclib (S) Prevents Cyclin A1 DNA Damage Induced Upregulation and Reduces Double Strand Break (DSB) Repair Through NHEJ Impairment

2010

Effect of phosphonate-functionalised nanoparticles on human mesenchymal stem cells and osteoclasts

2011

Numerical Analysis of Piezoelectric Active Repair in the Presence of Frictional Contact Conditions

2013

The increasing development of smart materials, such as piezoelectric and shape memory alloys, has opened new opportunities for improving repair techniques. Particularly, active repairs, based on the converse piezoelectric effect, can increase the life of a structure by reducing the crack opening. A deep characterization of the electromechanical behavior of delaminated composite structures, actively repaired by piezoelectric patches, can be achieved by considering the adhesive layer between the host structure and the repair and by taking into account the frictional contact between the crack surfaces. In this paper, Boundary Element (BE) analyses performed on delaminated composite structures …

Design and optimization of bonded patch repairs of laminated composite structures

2015

International audience; The present study proposes a method for design optimization of external patched repairs. The tensile behavior of notched specimens with patched repair was studied using finite element analysis and compared with experimental results. It was found that high stress concentrations along the transverse edges of circular patches and/or at the longitudinal edges of the hole leads to early damage initiation in the parent plate. The damage initiation site and its propagation depend on the patch in-plane stiffness. The optimal patch design can be characterized by a strength ratio R*. The overall design of the patch repair can be considered using a dimensionless design paramete…

Experienced knowledge for the description of maintenance packages

2015

International audience; The presented work is included in the research theme that specifies some means of capitalization andexploitation of knowledge from experience feedback processes in the context of industrial maintenancemanagement. Our research on it is a more precise definition of the proposed project, built with a problemasking how to handle the management of repair packages. Upstream, the knowledge of various expertsare materialized in the form of expert reports. Downstream maintenance wants to quickly repair productsbased on symptoms or change parts in advance. For this, we propose a methodology by analysing thefeedback to improve the response time for maintenance services. This is…

On the dynamic behavior of piezoelectric active repair by the boundary element method

2011

The dynamic behavior of piezoelectric active repair bonded on cracked structures is analyzed in this article. The boundary element code used to perform the simulations is implemented in the framework of piezoelectricity in order to model the coupling between the elastic and the electric fields, which represents the most important feature of piezoelectric media. The fracture mechanics problem, i.e. the crack, as well as the bonding layer between the host structure and the active patch is modeled by means of the multidomain technique provided with an interface spring model. More particularly, the spring interface model allows considering the bonding layer as a zero-thickness elastic ply char…