Search results for "stiffne"

The Rolf Method of Structural Integration on Fascial Tissue Stiffness, Elasticity, and Superficial Blood Perfusion in Healthy Individuals: The Prospe…

2020

Introduction: There are multiple theories surrounding the physiological impact of structural integration (SI) with little evidence or research corroborating any of these. The aim of the study was to assess the effectiveness of 10 sessions of SI on fascial tissue (FT) superficial blood perfusion, stiffness, and elasticity in 13 healthy women.Methods: This was a prospective, interventional study. The primary outcome measures were FTs’ superficial blood perfusion, stiffness, and elasticity of bilateral selected FT points on the body. Data were collected before and after 10 sessions of SI intervention. Statistical analysis was performed using the non-parametric Wilcoxon test (intragroup compari…

Relationship between plasma endothelin-1 and aortic stiffness in hypertensive patients with chronic kidney disease

2012

Effects of Different Long-Term Exercise Modalities on Tissue Stiffness

2022

AbstractStiffness is a fundamental property of living tissues, which may be modified by pathologies or traumatic events but also by nutritional, pharmacological and exercise interventions. This review aimed to understand if specific forms of exercise are able to determine specific forms of tissue stiffness adaptations. A literature search was performed on PubMed, Scopus and Web of Science databases to identify manuscripts addressing adaptations of tissue stiffness as a consequence of long-term exercise. Muscular, connective, peripheral nerve and arterial stiffness were considered for the purpose of this review. Resistance training, aerobic training, plyometric training and stretching were r…

Design and use of a Fatigue Test Machine in Plane Bending for Composite Specimens and Bonded Joints

2011

Polymeric and composites materials are increasingly used in industry as structural parts, so that specific information on their mechanical properties "at long term" (creep, relaxation, fatigue) are requested. The design and implementation of these components also requires that they are permanently connected together to perform certain functions. The use of adhesives in structural joints has increased over recent years thanks to the continuous development by companies which provide the market with adhesive having better and better mechanical properties. The main areas relate to the aerospace, aeronautical and automotive industries, where requirements are required for lightness and reliabilit…

Properties evolution of flax/epoxy composites under fatigue loading

2014

International audience; The tension-tension fatigue behaviour of flax fibre reinforced epoxy matrix composites have been investigated for specimens having [0]12, [90]12, [0/90]3S and [±45]3S lay-ups. The Probabilized Stress-Number of cycles (P-S-N) curves have been determined for each laminate type. The measured stress and strain data allowed to quantify the evolution of the mechanical properties, i.e. stiffness, damping and permanent strain as a function of imposed cycles. Especially, the stiffening phenomenon of flax reinforcements oriented parallel to the loading direction has been confirmed. However, due to the competition between damage development and the fibre stiffening, the increas…

Model of the mechanical response of short flax fiber reinforced polymer matrix composites

2011

Abstract Natural-fiber-reinforced short-fiber composites are finding more applications lately, therefore there is a need for estimation of the mechanical properties of such composites based on the properties of the constituents. The fibers themselves also possess complicated internal structure, resulting in anisotropy of their properties. Taking into account the internal structure of bast fiber, we evaluate the elastic properties of a composite unit cell, consisting of a fiber of average length and matrix according to the fiber volume fraction in the composite. The unit cell properties are used to estimate the stiffness of a misaligned short-fiber composite by means of orientation averaging…

Modeling elastic properties of short flax fiber-reinforced composites by orientation averaging

2010

Abstract Natural fibers of plant origin, used as reinforcement in polymer matrix composite materials, exhibit highly anisotropic elastic properties due to their complex internal structure. Mechanical properties can be evaluated not only by tests but also by mechanical models reflecting the principal morphological features of fibers. Such a FEM model is applied to estimate the elastic properties of a unit cell of a short-fiber-reinforced composite, an elementary flax fiber embedded in a polymer matrix. Orientation averaging approach is used for prediction of the stiffness of short flax fiber reinforced polymer matrix composite. The numerical estimates of Young’s modulus are compared to the t…

Arterial Stiffness is Associated With Moderate to Vigorous Physical Activity Levels in Post-Myocardial Infarction Patients.

2019

Arterial stiffness has shown independent predictive value for all-cause and cardiovascular mortalities, as well as fatal and nonfatal coronary events. Physical activity (PA) is associated with reduced cardiovascular morbidity and mortality. The study aims to analyze the cross-sectional association of arterial stiffness with objectively measured PA in patients following acute myocardial infarction.One hundred patients were consecutively recruited after experiencing an acute myocardial infarction. Central arterial stiffness was measured through carotid-femoral pulse wave velocity (cf-PWV) and daily PA was assessed objectively during 7 consecutive days with accelerometers. To be valid, data re…

Arterial stiffness in symptomatic smokers with normal lung function

2017

Chronic obstructive pulmonary disease (COPD) is associated with cardiovascular morbidity and mortality. Arterial stiffness and endothelial dysfunction index are validated surrogate cardiovascular markers and are increased in subjects with COPD. We tested whether increased arterial stiffness and endothelial dysfunction occur in symptomatic smokers with no evidence of bronchial obstruction. Clinical and lung functional assessments were conducted in smoker subjects with chronic respiratory symptoms and in COPD patients. Pulse wave velocity (PWV), aortic augmentation index (AIx) and reactive hyperaemia index (RHI) were measured to estimate the cardiovascular risk. 48 smokers (male n=37, female …

ASSOCIATION OF RENAL RESISTIVE INDEX WITH AORTIC PULSE WAVE VELOCITY IN HYPERTENSIVE PATIENTS.

2013

The assessment of renal hemodynamic parameters by duplex Doppler sonography has been used for many years as a diagnostic tool in the daily work-up of kidney diseases. Recent data suggest that these parameters, especially the intrarenal resistive index (RI) may be also associated with systemic vascular changes and with an enhanced cardiovascular risk. However, conflicting data exist in literature about the independent association of aortic stiffness with RI. The aim of this study was to evaluate the relationship between RI and arterial stiffness, assessed by aortic pulse wave velocity (PWV), in the hypertensive subjects consecutively attending our hypertension centre. We enrolled 264 subject…