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Background: Vascular risk factors are increasing rapidly in the Middle East. Growing inactivity and obesity have contributed to an epidemic of Type 2 diabetes mellitus (DM) in the Arab population. Microvascular palsies of the third, fourth, and sixth cranial nerves, which occur in an isolated manner, are relatively common in patients with DM, hypertension, or other vascular risk factors. Methods:

Background: The spatial peaks QRS-T (SPQRS-T) angle differentiates hypertrophic cardiomyopathy (HCM) patients from controls. Increased angle confers arrhythmia risk in other populations. Hypothesis: We predict that the SPQRS-T angle will identify HCM patients with sustained ventricular arrhythmias (VAs) and those with New York Heart Association class III/IV heart failure. Methods: Corrected QT int

What accounts for the differences in the economic performance across Italian regions in the post-Unification period? This thesis seeks to explain the regional patterns of economic development and industrialization in Italy in the period 1871-1911 by applying various Economic Geography models. The first part follows Overman and Puga (2002) and studies the distribution of industrial employment acros

Italy has been characterized, throughout its unitary history, by large regional differentials in income, level of industrialization, and development. This article aims at testing the New Economic Geography hypothesis on the role of market access in explaining these regional differentials. We first quantify the market potentials of the Italian regions. We then use these estimates to study the causa

Presented here is a novel and efficient method used to improve carrier mobilities of poly(3-hexylthiophene) (P3HT)-based organic field effect transistors by means of nanowire formation. The treatment, termed solvation, consists of depositing a small quantity of a solvent directly on top of a previously deposited semiconducting film, and allowing the solvent to evaporate slowly. Such treatment resu

This study is aimed at clarifying the microscopic mechanisms that determine a pronounced asymmetry of plastic deformation with respect to tension and compression in magnesium alloys, even having a random texture. The specific object of the present investigation is the Mg-Zn-Zr alloy ZK60. The mechanisms in question are based on a synergistic interplay between dislocation slip and deformation twinn

Creating bimodal grain size distribution in crystalline materials is an effective strategy to improve structural efficiency. Present investigation demonstrates that further control over topology through the formation of bimodal 'harmonic' structure simultaneously increases average values of strength and ductility, reduces the variation of corresponding properties, and thwarts the localization of p

The effects of annealing on the microstructure, texture, tensile properties, and R value evolution of an IF steel sheet after room-temperature symmetric and asymmetric rolling were examined. Simulations were carried out to obtain R values from the experimental textures using the viscoplastic self-consistent polycrystal plasticity model. The investigation revealed the variations in the textures due

The evolution of intermetallic precipitate particles in Mg-Zn-Zr alloy ZK60 during thermomechanical processing by integrated extrusion and equal channel angular pressing was investigated in detail. Electron microscopy was employed to analyse individual particles and their orientation within the Mg matrix, while small-angle X-ray scattering (SAXS) was used for an assessment of global particle behav

Pure copper (Cu) having bimodal 'harmonic structure' (HS) was fabricated by a technique based on severe plastic deformation of powders, which involved tailored mechanical milling and spark plasma sintering. The harmonic-structured Cu demonstrates a unique combination of high strength and large elongation superior to its homogeneous as well as bimodal heterogeneous counterparts. Specific features o

The effect of ultrafine-grained structure formation in Mg-Zn-Zr alloy ZK60 on its mechanical response was investigated at strain rates ranging from quasi-static to dynamic regimes. The study demonstrated that the strength characteristics of the material rise significantly with increasing strain rate, while its ductility is reduced. These effects are particularly pronounced in the dynamic loading r

IF steel sheets were processed by conventional symmetric and asymmetric rolling (ASR) at ambient temperature. The asymmetry was introduced in a geometric way using differential roll diameters with a number of different ratios. The material strength was measured by tensile testing and the microstructure was analyzed by optical and transmission electron microscopy as well as electron backscatter dif

The present study has clarified the roles of dislocation slip and twinning as the deformation mechanisms in magnesium alloys, as well as the effect of grain size on their relative contributions. The details of these mechanisms were studied by monitoring acoustic emission (AE) in conjunction with a novel signal categorization technique in Mg alloy ZK60. Through the analysis of AE time series the se

Materials having bimodal grain structures are known for the good balance of strength and ductility. However, methods for their fabrication often lack the control of such structure characteristics. In this work, the principles of "harmonic" structure fabrication allowing to control both topology and scale of the bimodal structure heterogeneity have been concisely formulated. The feasibility to form

Fatigue performance under axisymmetric push-pull loading of a magnesium alloy Mg-6Zn-0.5Zr (ZK60) after processing by integrated extrusion and equal-channel angular pressing was investigated. Such processing was shown to nearly treble the endurance limit of the alloy, raising it to 160 MPa. It was established that the high-cycle fatigue performance of ZK60 is primarily controlled by dislocation su

High-pressure torsion was used for the deformation processing of high-purity aluminum (4N-Al), while high-resolution electron-backscatter diffraction was used for the analysis of evolution of qualitative and quantitative microstructural characteristics. This study reveals a rather full picture of microstructure evolution in the high stacking fault energy fcc material and makes a continuous link be

In the present work, effects of loading scheme and strain reversal on structure and hardness evolution have been studied by using high pressure torsion (HPT) and twist extrusion (TE) techniques. High purity aluminium (99.99%) was processed at room temperature up to a maximum total equivalent strain of εmax ≈ 8 by TE, and HPT in monotonic and reversal deformation modes with strain increment Δεmax =

In the present study, the effects of kinematic and geometric asymmetries in rolling during multi-pass processing of IF steel are examined. The theoretical investigation by final element simulations and experimental investigations by means of electron-backscatter diffraction analysis and tensile tests suggest that asymmetric rolling increases the total imposed strain compared to symmetric rolling,

Asymmetric rolling (ASR) is a potential process to reach better grain refinement than in conventional rolling, thus, can lead to better mechanical properties. It is not known, however, how the introduction of a shear component will change the ideal orientations of the textures, and consequently, the evolution of plastic anisotropy. To understand the effect of the added shear on texture evolution i