Search results for "Ultra"

Contact between the components of a knee prosthesis: numerical and experimental study

2012

The aim of this work is the analysis of the contact area in a knee prosthesis using two different approaches. In particular, the interface between the femoral component and the polyethylene insert has been studied both numerically and experimentally. The interest in studying the contact area is related to the fact that the wear of the polyethylene insert, due to the high contact pressures, represents one of the major causes of failure of the total knee prosthesis. The possibility to evaluate the contact area at different loads and mutual position between femur and tibia is, therefore, of fundamental importance to study the service life of a prosthesis and to improve its performance. The fin…

Integrismo político en EEUU / 5. El eje nacional-populista

2004

DICER and ZRF1 contribute to chromatin decondensation during nucleotide excision repair

2016

Abstract Repair of damaged DNA relies on the recruitment of DNA repair factors in a well orchestrated manner. As a prerequisite, the chromatin needs to be decondensed by chromatin remodelers to allow for binding of repair factors and for DNA repair to occur. Recent studies have implicated members of the SWI/SNF and INO80 families as well as PARP1 in nucleotide excision repair (NER). In this study, we report that the endonuclease DICER is implicated in chromatin decondensation during NER. In response to UV irradiation, DICER is recruited to chromatin in a ZRF1-mediated manner. The H2A–ubiquitin binding protein ZRF1 and DICER together impact on the chromatin conformation via PARP1. Moreover, …

Indagini 3D di dettaglio per l’analisi dell’integrità del busto di Eleonora d’Aragona (F. Laurana, 1468

2009

Current-induced domain wall motion in nanoscale ferromagnetic elements

2011

The manipulation of a magnetic domain wall (DW) by a spin polarized current in ferromagnetic nanowires has attracted tremendous interest during the last years due to fundamental questions in the fields of spin dependent transport phenomena and magnetization dynamics but also due to promising applications, such as DW based magnetic memory concepts and logic devices. We comprehensively review recent developments in the field of geometrically confined domain walls and in particular current induced DW dynamics. We focus on the influence of the magnetic and electronic transport properties of the materials on the spin transfer effect in DWs. After considering the different DW structures in ferrom…

Melanomas apzināšanās un riska uzvedība starp universitāšu studentiem

2016

Melanomas sastopamība turpina pieaugt visā pasaulē, it īpaši jaunu eiropeīdu pieaugušo vidū. Ir svarīgi identificēt riska faktorus un sniegt zināšanas par melanomu, lai varētu novērst tās rašanos. Pētījuma mērķis bija noskaidrot atšķirības starp valstīm un fakultātēm saistībā ar melanomas apzināšanos un riska uzvedību, it īpaši analizējot, vai labāka melanomas apzināšana samazina riska uzvedību. Šis kross-sekcionālais pētījums iekļāva Latvijas un Somijas universitāšu studentus no divām dažādām fakultātēm (medicīnas un fizikas). Mūsu pētījums atklāja, ka melanomas apzināšana neparedz ar sauļošanos saistītas riskantas uzvedības mazināšanos. Starp fakultātēm un nacionalitātēm pastāv atšķirības…

Severity of Asymptomatic Carotid Stenosis and Risk of Ipsilateral Hemispheric Ischaemic Events: Results from the ACSRS Study

2005

Objectives. This study determines the risk of ipsilateral ischaemic neurological events in relation to the degree of asymptomatic carotid stenosis and other risk factors. Methods. Patients (n = 1115) with asymptomatic internal carotid artery (ICA) stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6-84 (mean 37.1) months. Stenosis was graded using duplex, and clinical and biochemical risk factors were recorded. Results. The relationship between ICA stenosis and event rate is linear when stenosis is expressed by the ECST method, but S-shaped if expressed by the NASCET method. In addition to the ECST grade of stenosis (RR 1.6; 95% CI 1.21-2.15), histor…

Zr, Hf and REE distribution in river water under different ionic strength conditions

2018

International audience; The Platani River flowing in south-central Sicily, interacting with evaporite rocks, generates a wide range of ionic strength in the water catchment from 0.1 to 5.0 mol kg−1. We sampled 38 river sites and analysed the composition for the dissolved fraction filtered through 0.45 μm, the truly dissolved fraction obtained through ultrafiltration (10 kDa) and the relative included colloidal fraction.This study was focused on the recognition of Zr, Hf and REE behaviour under changing ionic strength conditions, since this is one of parameters responsible for colloid stability in natural waters. In turn, this phenomenon leads to REE release from the colloidal fraction and t…

Introducing a new method for efficient visualization of complex shape 3D ultrasonic phased-array C-scans

2017

Automated robotic inspection systems allow the collection of large data volumes, compared to existing inspection systems. To maximize the throughput associated with the non-destructive evaluation phase, it is crucial that the reconstructed inspection data sets are generated and examined rapidly without a loss of detail. Data analysis often becomes the bottleneck of automated inspections. Therefore, new data visualization tools, suitable to screen the NDT information obtained through robotic systems, are urgently required. This paper presents a new approach, for the generation of three-dimensional ultrasonic C-scans of large and complex parts, suitable for application to high data throughput…

Evaluation of apical preparations performed with ultrasonic diamond and stainless steel tips at different intensities using a scanning electron micro…

2011

Objective: The objective of our study is to analyse (with the help of scanning electron microscopes) the quality of the dental root surface and the appearance of dental cracks after performing apical preparations using two diffe-rent types of ultrasonic tips. Study design: We used 32 single-rooted teeth that underwent a root canal and apical resection. Afterwards, the teeth were divided into 4 groups of 8 teeth each, with preparations of the apical cavities in the following manner: Group 1: stainless steel ultrasonic tip at 33KHz. Group 2: stainless steel ultrasonic tip at 30KHz. Group 3: diamond ultrasonic tip at 30KHz. Group 4: diamond ultrasonic tip at 33 KHz. The quality of the root sur…