Search results for "Elasticity"
showing 10 items of 736 documents
Advancing frontiers in rheumatic and musculoskeletal imaging.
2021
AbstractIn recent years, technological improvements allowed imaging modalities to become increasingly essential in achieving early and precise diagnoses in the field of rheumatic and musculoskeletal diseases (RMDs). To date, imaging examinations are routinely used in all steps of diagnostic and therapeutic care pathways of patients affected by RMDs. The articles published in this Article Collection clearly show the efforts of researchers to find innovative applications of musculoskeletal imaging in clinical practice and to face the crucial challenges that remain in the interpretation and quality control of images. Highly performing diagnostic technologies are currently available to early di…
The EFSUMB Guidelines and Recommendations for the Clinical Practice of Elastography in Non-Hepatic Applications: Update 2018
2019
This manuscript describes the use of ultrasound elastography, with the exception of liver applications, and represents an update of the 2013 EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology) Guidelines and Recommendations on the clinical use of elastography.Diese Arbeit beschreibt den Einsatz der Ultraschall-Elastografie mit Ausnahme der Leberanwendungen und ist eine Aktualisierung der Leitlinien und Empfehlungen der EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology) von 2013 zum klinischen Einsatz der Elastografie.
Employment effects of reducing labour costs : considering potential bias in macro-estimates of the elasticity of labour demand
2017
In 2016 the Finnish government decided to implement the competitiveness pact in order to increase employment. The objective is to improve cost-competitiveness by lowering labor costs in the private sector. The elasticity of labour demand plays a key role in assessing the employment effects of the competitiveness pact. The idea of this study is based on the Economic Policy Council Report (2016) which argued that the government’s elasticity estimate is very high and predicts overly optimistic employment effects. The majority of studies estimate demand elasticities using aggregate data, which is likely to produce biased estimates. The problems relate in particular to the lack of exogenous vari…
Mixed Finite Elements for multilayered smart plates nonlocal analysis
2022
A mixed finite element formulation for the Eringen’s nonlocal analysis of smart, magneto-electro-elastic, multilayered plates is presented. Finite elements for different refined higher order plate layerwise theories are systematically developed. They ensure interface continuity and allow associating different values of the nonlocal parameter to the laminate layers. Standard 9-node and 16-node isoparametric, quadrilateral finite elements have been implemented and tested, showing the characteristics and limitations of the proposed approach.
Quasi-Fractional Models of Human Tendons Hereditariness
2018
In this study, the authors, after collecting a series of experimental evidences following a creep and relaxation tendon campaign, propose a non-linear model of the viscoelastic behavior of the tendons. The ligaments investigated are the patellars and the hamstrings. The analytical model proposed by the authors aims to explain the non-linear hereditary behavior of these tissues and proposes an approach with which to develop a hereditary fractional-order non-linear model.
The influence of the decompressive operation on the intracranial pressure and the pressure-volume relation in patients with severe head injuries.
1978
Measurements of intracranial pressure by ventricular catheter were performed in 47 patients with severe head injuries. Thirty-three patients with decompressive operations such as osteoclastic craniotomy and dilatation by means of duraplastic have been compared with 14 patients with closed heads with regard to volume pressure response (intracranial elasticity). This was determined either by intraventricular injection of 2 ml saline or by drainage of cerebrospinal fluid. The examination clearly shows that patients with closed heads have a much higher intracranial elasticity than patients who have decompressive operations, so that in the first group minor differences of the intracranial volume…
Warm-Up and Hamstrings Stiffness, Stress Relaxation, Flexibility, and Knee Proprioception in Young Soccer Players
2022
Context: Nerves or fascia may limit motion in young soccer players, thereby contributing to frequent hamstring injuries. Nerve gliding exercises and self-myofascial release techniques may enhance the range of motion. Objective: The aim of this study was to compare the acute effect of foam rolling (FR) and neurodynamic nerve gliding (NDNG) on hamstring flexibility, passive stiffness, viscoelasticity and proprioception during the warm-up of soccer players. Design: Crossover study design. Setting: Research laboratory. Participants: Fifteen male soccer players on the same team (age 18.0 ± 1.4 years, body mass 76.9 ± 7.8 kg, height 183 ± 6 cm). Intervention: FR and NDNG included six sets of 45 s…
Refined layer-wise models for nonlocal analysis of magneto-electro-elastic plates
Size-dependent theories of continuum mechanics are an important tool for structural and material modeling in engineering applications, with particular regard to those involving micro- and nano-scales. Among various approaches proposed in the literature to account for the effect of the microstructure via continuum models, the Eringen’s nonlocal elasticity model incorporates important features of material behavior via a differential stress-strain relationship involving a scale coefficient, or characteristic length, depending on the material microstructure [1]. In the framework of Eringen’s nonlocal elasticity, plate theories have been reformulated for homogeneous and multilayered configuratio…
Static instability analysis of an elastic band travelling in the gravitational field
2011
Static instability analysis is performed for an axially moving elastic band, which is travelling at a constant velocity in a uniform gravitational field between two supports. The buckling of the band is investigated with the help of admitting small transverse deflections. The model of a thin elastic beam (panel) subjected to bending, centrifugal forces and nonhomogeneous tension (including a gravitational term) is used. Buckling analysis and estimation of the critical velocities of elastic instability are based on variational principles and variational inequalities. As a result, explicit formulas for upper and lower limits for critical velocities are found. It is shown analytically that a c…
On the high-pressure phase stability and elastic properties ofβ-titanium alloys
2017
We have studied the compressibility and stability of different β-titanium alloys at high pressure, including binary Ti–Mo, Ti–24Nb–4Zr–8Sn (Ti2448) and Ti–36Nb–2Ta–0.3O (gum metal). We observed stability of the β phase in these alloys to 40 GPa, well into the ω phase region in the P–T diagram of pure titanium. Gum metal was pressurised above 70 GPa and forms a phase with a crystal structure similar to the η phase of pure Ti. The bulk moduli determined for the different alloys range from 97 ± 3 GPa (Ti2448) to 124 ± 6 GPa (Ti–16.8Mo–0.13O).