First approximation of the zero-stress state of arterial wall and contraction of SMC

The article provides general information about double-support mobile bridges designed for contactless movement of heavily loaded specialized multi-axle wheeled vehicles on top of man–made structures. Also, recommendations are given on substantiating the possibility of their use for solving specific problems. These recommendations contain expressions obtained by the methods of structural mechanics, on the basis of which it is possible to determine not only the required (minimum) camber of the mobile bridge, which is necessary to ensure the normal passage of the vehicle, but also to assess the stress state of the mobile bridge, as well as to determine the nature of the deformation of the mobile bridge when vehicle moves along it. The presented recommendations allow, at a first approximation, to assess the suitability of the available solutions of a mobile bridge for the passage of specialized multi-axle vehicles over mane–made structures, depending on the required span of the mobile bridge and the load from the vehicle on the mobile bridge. The article also provides an example of solving a specific problem on the basis of these recommendations, in accordance with which, when a mobile bridge is spanned 23.4 m and a working load from one axis of the vehicle is equal to 33.5 tons, the required camber is 400 mm, and the highest equivalent stresses will be about 380 MPa.

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Experimental Investigation of the Distribution of Residual Strains in the Artery Wall

Journal of Biomechanical Engineering ◽

10.1115/1.2798291 ◽

1997 ◽

Vol 119 (4) ◽

pp. 438-444 ◽

Cited By ~ 145

Author(s):

S. E. Greenwald ◽

J. E. Moore ◽

A. Rachev ◽

T. P. C. Kane ◽

J.-J. Meister

Keyword(s):

Smooth Muscle ◽

Stress State ◽

Smooth Muscle Cells ◽

Residual Strain ◽

Arterial Wall ◽

Normal Growth ◽

Muscle Cells ◽

Opening Angle ◽

Artery Wall ◽

Residual Strains

Arterial wall stresses are thought to be a major determinant of vascular remodeling both during normal growth and throughout the development of occlusive vascular disease. A completely physiologic mechanical model of the arterial wall should account not only for its residual strains but also for its structural nonhomogeneity. It is known that each layer of the artery wall possesses different mechanical properties, but the distribution of residual strain among the different mechanical components, and thus the true zero stress state, remain unknown. In this study, two different sets of experiments were carried out in order to determine the distribution of residual strains in artery walls, and thus the true zero stress state. In the first, collagen and elastin were selectively eliminated by chemical methods and smooth muscle cells were destroyed by freezing. Dissolving elastin provoked a decrease in the opening angle, while dissolving collagen and destroying smooth muscle cells had no effect. In the second, different wall layers of bovine carotid arteries were removed from the exterior or luminal surfaces by lathing or drilling frozen specimens, and then allowing the frozen material to thaw before measuring residual strain. Lathing material away from the outer surface caused the opening angle of the remaining inner layers to increase. Drilling material from the inside caused the opening angle of the remaining outer layers to decrease. Mechanical nonhomogeneity, including the distribution of residual strains, should thus be considered as an important factor in determining the distribution of stress in the artery wall and the configuration of the true zero stress state.

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A Mixed Experimental-Numerical Estimation Strategy to Characterize Arterial Wall Properties Including Residual Strains

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-206241 ◽

2009 ◽

Author(s):

Arjen van der Horst ◽

Chantal N. van den Broek ◽

Marcel C. M. Rutten ◽

Frans N. van de Vosse

Keyword(s):

Stress State ◽

Constitutive Model ◽

Mechanical Behavior ◽

Arterial Wall ◽

Numerical Estimation ◽

Estimation Strategy ◽

Wall Properties ◽

Residual Strains

To model materials mechanically, it is necessary to determine the parameters of the constitutive model which determine its mechanical behavior. To be able to do this correctly it is important to know the zero-stress state of the material.

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2A23 Arterial Wall Modeling and Medical Image Mapping Based on Element-Based Zero-Stress State Estimation Method

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME ◽

10.1299/jsmebio.2015.27.315 ◽

2015 ◽

Vol 2015.27 (0) ◽

pp. 315-316

Author(s):

Takafumi SASAKI ◽

Kenji TAKIZAWA ◽

Keiichi ITATANI ◽

Hirokazu TAKAGI ◽

Tayfun E. Tezduyar ◽

...

Keyword(s):

Stress State ◽

State Estimation ◽

Medical Image ◽

Arterial Wall ◽

Estimation Method ◽

Image Mapping

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66 Arterial wall properties in patients with chronic heart failure

European Journal of Heart Failure Supplements ◽

10.1016/s1567-4215(06)80032-9 ◽

2006 ◽

Vol 5 (1) ◽

pp. 11-12

Author(s):

Z KOBALAVA ◽

V MOISEEV ◽

Y KOTOVSKAYA ◽

G KIYAKBAEV ◽

E OZOVA

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Arterial Wall ◽

Wall Properties

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540 Effects of atorvastatin on serum markers of inflammation, arterial wall properties and haemodynamic parameters in patients with ischaemic heart failure

European Journal of Heart Failure Supplements ◽

10.1016/s1567-4215(07)60346-4 ◽

2007 ◽

Vol 6 (1) ◽

pp. 123-124

Author(s):

E OZOVA ◽

Z KOBALAVA ◽

V MOISEEV ◽

G KIYAKBAEV

Keyword(s):

Heart Failure ◽

Arterial Wall ◽

Serum Markers ◽

Haemodynamic Parameters ◽

Markers Of Inflammation ◽

Wall Properties

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Short Stress State Questionnaire

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000200 ◽

2015 ◽

Vol 31 (1) ◽

pp. 20-30 ◽

Cited By ~ 28

Author(s):

William S. Helton ◽

Katharina Näswall

Keyword(s):

Stress State ◽

Factor Structure ◽

Human Performance ◽

Self Report ◽

Confirmatory Factor ◽

Stress States ◽

Related Stress ◽

Using Data ◽

Task Conditions ◽

Multiple Samples

Conscious appraisals of stress, or stress states, are an important aspect of human performance. This article presents evidence supporting the validity and measurement characteristics of a short multidimensional self-report measure of stress state, the Short Stress State Questionnaire (SSSQ; Helton, 2004 ). The SSSQ measures task engagement, distress, and worry. A confirmatory factor analysis of the SSSQ using data pooled from multiple samples suggests the SSSQ does have a three factor structure and post-task changes are not due to changes in factor structure, but to mean level changes (state changes). In addition, the SSSQ demonstrates sensitivity to task stressors in line with hypotheses. Different task conditions elicited unique patterns of stress state on the three factors of the SSSQ in line with prior predictions. The 24-item SSSQ is a valid measure of stress state which may be useful to researchers interested in conscious appraisals of task-related stress.

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