Search results for "Stiffness"
showing 10 items of 524 documents
SURFACE AND MECHANISTIC PROPERTIES OF RECYCLED BITUMINOUS MIXTURES
2019
EXECUTIVE SUMMARY Problem Often, when the characteristics of a bituminous mixture are analised, there are major differences between in-lab and in-situ results. This is due to the fact that the procedures and techniques implemented during the design phase (in lab) may be different from those used on site. Then, is very important to be able to predict the main properties of a mixture particularly when innovative materials are used. For example, when crumb rubber is used, phisical and volumetric properties of mixes may change over time, in particular due to the swelling phenomenon that it alters different properties of the mixture (e.g., viscosity). This study aims to investigate the main aspe…
Scrutiny of the Failure of Lipid Membranes As A Function of Headgroups, Chain Length, and Lamellarity Measured by Scanning Force Microscopy
2004
AbstractA fast, quantitative, and unambiguous screening of material properties of biomembranes using scanning force microscopy in pulsed force mode on lipid membranes is presented. The spatially resolved study of breakthrough force, breakthrough distance, adhesion, stiffness, and topography of lipid membranes as determined simultaneously by digitalized pulsed force mode provides new insight into the structure-function relationship of model membranes, which are systematically analyzed by varying chain length, lipid headgroup, and lamellarity. For this purpose, a novel unbiased analysis method is presented. A strong correlation between adhesion and breakthrough events is found on lipid bilaye…
Comparison of two techniques (in vivo and ex-vivo) for evaluating the elastic properties of the ascending aorta: Prospective cohort study.
2021
Introduction Aneurysms of the ascending aorta (AA) correspond to a dilatation of the ascending aorta that progressively evolves over several years. The main complication of aneurysms of the ascending aorta is type A aortic dissection, which is associated with very high rates of morbidity and mortality. Prophylactic ascending aorta replacement guidelines are currently based on maximal AA diameter. However, this criterion is imperfect. Stretching tests on the aorta carried out ex-vivo make it possible to determine the elastic properties of healthy and aneurysmal aortic fragments (tension test, resistance before rupture). For several years now, cardiac magnetic resonance imaging (MRI) has pro…
Intake of Vitamin K Antagonists and Worsening of Cardiac and Vascular Disease: Results From the Population‐Based Gutenberg Health Study
2018
Background Preclinical data have indicated a link between use of vitamin K antagonists ( VKA ) and detrimental effects on vascular structure and function. The objective of the present study was to determine the relationship between VKA intake and different phenotypes of subclinical cardiovascular disease in the population. Methods and Results Clinical and laboratory data, as well as medical–technical examinations were assessed from 15 010 individuals aged 35 to 74 years during a highly standardized 5‐hour visit at the study center of the population‐based Gutenberg Health Study. In total, the study sample comprised 287 VKA users and 14 564 VKA nonusers. Multivariable analysis revealed an in…
Mean Platelet Volume and Arterial Stiffness - Clinical Relationship and Common Genetic Variability
2017
AbstractVessel wall stiffening is an important clinical parameter, but it is unknown whether platelets, key elements in the pathogenesis of arterial thrombosis, are associated with arterial stiffness. The present studies sought to determine whether mean platelet volume (MPV), a potential marker of platelet activation, is linked to vascular elasticity as assessed by the augmentation index (AIx), in 15,010 individuals from the population-based Gutenberg Health Study. Multivariable analysis showed that MPV in both males (β 0.776; 95thCI [0.250;1.16]; p = 0.0024) and females (β 0.881[0.328;1.43]; p = 0.0018) is strongly associated with AIx. Individuals with MPV and AIx above the sex-specific me…
Plantarflexor Muscle-Tendon Properties are Associated With Mobility in Healthy Older Adults
2015
BACKGROUND: Muscle mass, strength, and power are known determinants of mobility in older adults but there is limited knowledge on the influence of muscle architecture or tendon properties on mobility. The purpose of this study was to examine the relationship between mobility and plantarflexor muscle-tendon properties in healthy older adults.METHODS: A total of 52 subjects (age 70-81 years) were measured for 6-minute walk test (6MWT), timed "up and go"-test (TUG), isometric plantarflexion strength, Achilles tendon stiffness, triceps surae muscle architecture, lower extremity lean mass, isometric leg extension strength, and leg extension power. Partial correlations and multivariate regression…
Short-Term Effects of a Combined Nutraceutical on Lipid Level, Fatty Liver Biomarkers, Hemodynamic Parameters, and Estimated Cardiovascular Disease R…
2017
Introduction: There is a growing interest in nutraceuticals improving cardiovascular risk factor levels and related organ damage. Methods: This double-blind, placebo-controlled randomized clinical trial aims to compare the effect of a combined nutraceutical containing red yeast rice (10Â mg), phytosterols (800Â mg), and l-tyrosol (5Â mg) on lipid profile, blood pressure, endothelial function, and arterial stiffness in a group of 60 patients with polygenic hypercholesterolemia resistant to Mediterranean diet. Results: After 8 weeks of treatment, when compared to the placebo group, the active treated patients experienced a more favorable percentage change in total cholesterol (â16.3% vs 9.9…
Cardiovascular Toxicity in Cancer Patients Treated with Tyrosine Kinase Inhibitors: A Real-World Single-Center Experience
2019
<b><i>Background:</i></b> Target therapy can cause various cardiovascular complications. The aim of this study was to evaluate the burden of cardiovascular complications related to treatment with anti-BCR-ABL tyrosine kinase inhibitors (TKIs) and to determine if there are differences between the latest- and first-generation TKIs. <b><i>Methods:</i></b> A retrospective observational study was carried out on 55 patients (39 men, 16 women; mean age ± SD: 58 ± 11 years) treated with TKIs targeting Bcr-Abl for a median period of 3.5 years. Patients were divided in two groups according to the type of treatment. Group A included patients treated with…
Automatic or manual arterial path for the ankle-brachial differences pulse wave velocity
2018
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0206434 An automated method for measuring arterial path length with devices that determine pulse wave velocity (PWV) in peripheral arteries is frequently applied. We aimed to compare arterial path length measurements based on mathematical height-based formulas with those measured manually and to assess whether the ankle-brachial difference (abD-PWV) measured with the VOPITB device is comparable to that obtained by manual measurements. In 245 patients, a metric measuring tape was used to determine the arterial path length from the suprast…
Are Morphological or Functional Changes in the Carotid Artery Wall Associated With Chlamydia pneumoniae, Helicobacter pylori, Cytomegalovirus, or Her…
2000
Background and Purpose —Chronic infection with Chlamydia pneumoniae , Helicobacter pylori , cytomegalovirus (CMV), and herpes simplex virus (HSV) has been implicated in the pathogenesis of atherosclerosis. The carotid intima-media thickness (IMT) can be taken to indicate early atherosclerosis, the presence of a carotid stenosis is a marker of a manifest carotid atherosclerosis, and an increase in arterial stiffness is used as marker of structural and functional changes in an atherosclerotic vessel wall. Methods —In 504 patients (75% men; mean age 62.9 [SD 10] years), we measured the IMT and the elastic pressure modulus (EP; n=445) of the common carotid artery and the prevalence of a intern…