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Electrocardiographic algorithms are particularly useful to differentiate, in the presence of a wide complex tachycardia, between supraventricular aberrancy and ventricular tachycardias (VT). There are numerous limitations to the sensitivity and specificity of these algorithms including the presence of accessory pathways, use of antiarrhythmic drugs, congenital heart diseases, electrolytes impairments, and artificial pacing. Once the diagnosis of VT has been reached, other algorithms can help in localizing the origin of the ventricular arrhythmia. These approaches are also limited by the anatomic structure of where the arrhythmia originates. This article illustrates the difficulties in applying common algorithms in many clinical circumstances. [ABSTRACT FROM AUTHOR]

Abstract: The broad use of titanium alloys in naval, automotive and aerospace applications expects the current research to shed light on the fatigue behavior of these materials in corrosive media and notched condition. In this respect, the fatigue behavior in air and NaCl solution of notched Ti-6Al-4V flat dogbone samples was investigated. A step-loading method was used to generate data points on fatigue limit stress vs. Kt diagrams for a constant life of 200,000 load cycles at R = 0.1. Fracture surfaces were observed using stereoscopic microscope. [Copyright &y& Elsevier]

Abstract: The effect of a physically vapor deposited (PVD) WC/C coating on the fatigue behavior of as produced and foreign object damaged (FOD) solution heat treated and aged 7075 aluminum alloy was studied. Coated and uncoated samples were tested under rotating bending to determine the fatigue strengths between 104 and 106 cycles in both damaged and smooth condition. FOD was produced with single shots of small hard steel spheres impacting at 100 m/s in the minimum cross section. SEM was used to characterize the features of the fracture surfaces. [Copyright &y& Elsevier]

Abstract: This work studies the rolling contact fatigue (RCF) behaviour of case-hardened transmission gears for racing motorcycles both numerically and experimentally. Both as-produced and PVD-WC/C coated conditions are analyzed. Finite element models of the gears were developed and a calculation procedure was applied to predict their RCF life. The Ti-6Al-4V alloy was also considered to investigate the mass decrease of the components. RCF tests were carried out in both dry and lubricated conditions. The experimental results were compared with the numerical ones to check the reliability of the predictive method proposed. [Copyright &y& Elsevier]

Abstract: The thin hard coating deposition techniques CVD and PVD have been used for a long time in industry. Such coatings prove very effective in improving the tribological and corrosive resistant properties of the substrate. It was shown that the compressive residual stresses are introduced on the surface layer from the PVD deposition process that helps to increase the fatigue limit of coated structural components. The aim of this work is to evaluate the effect of a SiO x coating, deposited by means of PECVD technique, on the fatigue resistance of a quenched and tempered alloy steel (39NiCrMo3). Rotating bending fatigue tests were carried out to assess its fatigue limit and characterize any possible variation between the coated and the uncoated material. Fracture surface observations were made using SEM on fracture surfaces, and scratch tests were performed on samples to assess the coating-substrate interface delamination. [Copyright &y& Elsevier]

We report a successfully treated case of spondylodiscitis and bloodstream infection due to vancomycin heteroresistant Staphylococcus capitis , in an adult immunocompetent patient with multiple antibiotics intolerance. S. capitis is rarely involved in osteomyelitis and, to our knowledge, this is the first report of vancomycin heteroresistance phenomenon in an S. capitis strain causing spondylodiscitis. [ABSTRACT FROM AUTHOR]