Preliminary Clinical Results and Mechanical Behavior of a New Double-Layer Carotid Stent

Plate-cone reticulated shell is a new type of space structures with good mechanical behavior and technical economy. In this dissertation, plate-cone reticulated shell is equated to double-layer reticulated shell with two kinds of material members. The internal forces and the displacement of plate-cone reticulated shell can be calculated by space truss displacement method.

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Influences of Uncertainties on Mechanical Behavior of a Double-Layer Space Truss

International Journal of Space Structures ◽

10.1177/026635119200700306 ◽

1992 ◽

Vol 7 (3) ◽

pp. 223-235 ◽

Cited By ~ 10

Author(s):

Akira Wada ◽

Zhu Wang

Keyword(s):

Mechanical Behavior ◽

Double Layer ◽

Human Error ◽

Minimum Weight ◽

Initial Imperfection ◽

Minimum Weight Design ◽

Space Truss ◽

The Monte Carlo Method ◽

Weight Design ◽

Statistical Studies

A space truss, as all other structures, is constantly subject to various types of uncertainties. For the purpose of estimating, and furthermore, ensuring the safety of a space truss, it is important to investigate its mechanical behavior with consideration of the influences of uncertainties. A 6 × 6 square-plan, double-layer space truss is designed in accordance with minimum weight design concept and used as an example to study. A computer program is written to analyze the truss structure, with an ability to simulate member buckling. The Monte Carlo method is applied for statistical studies with trial number of each study set to 100. The variation of member strength, initial imperfection of member length are chosen for component uncertainties, and the error in assembly process is chosen for human error. The mechanical behavior of the space truss influenced by these uncertainties is studied. A comparison between the influences of the component's uncertainties originating in human error, is made to determine where the most critical uncertainties lie.

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An Analytical Study on Mechanical Behavior of Human Arteries – A Nonlinear Elastic Double Layer Model

Scientia Iranica ◽

10.24200/sci.2018.5707.1433 ◽

2018 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

Ali Reza Saidi ◽

Amin Jahanshahi

Keyword(s):

Mechanical Behavior ◽

Double Layer ◽

Analytical Study ◽

Layer Model ◽

Double Layer Model ◽

Human Arteries ◽

Nonlinear Elastic

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Clinical Results and Mechanical Properties of the Carotid CGUARD Double-Layered Embolic Prevention Stent

Journal of Endovascular Therapy ◽

10.1177/1526602816671134 ◽

2016 ◽

Vol 24 (1) ◽

pp. 130-137 ◽

Cited By ~ 20

Author(s):

Christian Wissgott ◽

Wolfram Schmidt ◽

Christoph Brandt-Wunderlich ◽

Peter Behrens ◽

Reimer Andresen

Keyword(s):

Mechanical Properties ◽

Double Layer ◽

Clinical Results ◽

Radial Force ◽

Bending Stiffness ◽

Lesion Length ◽

Collapse Pressure ◽

Stent System ◽

In Vitro Investigation

Purpose: To report early clinical outcomes with a novel double-layer stent for the internal carotid artery (ICA) and the in vitro investigation of the stent’s mechanical properties. Methods: A prospective single-center study enrolled 30 consecutive patients (mean age 73.1±6.3 years; 21 men) with symptomatic (n=25) or high-grade (n=5) ICA stenosis treated with the new double-layer carotid CGUARD Embolic Prevention System (EPS) stent, which has an inner open-cell nitinol design with an outer closed-cell polyethylene terephthalate layer. The average stenosis of the treated arteries was 84.1%±7.9% with a mean lesion length of 16.6±2.1 mm. In the laboratory, 8×40-mm stents where tested in vitro with respect to their radial force during expansion, the bending stiffness of the stent system and the expanded stent, as well as the collapse pressure in a thin and flexible sheath. The wall adaptation was assessed using fluoroscopy after stent release in step and curved vessel models. Results: The stent was successfully implanted in all patients. No peri- or postprocedural complications occurred; no minor or major stroke was observed in the 6-month follow-up. The bending stiffness of the expanded stent was 63.1 N·mm2 and (not unexpectedly) was clearly lower than that of the stent system (601.5 N·mm2). The normalized radial force during expansion of the stent to 7.0 mm, consistent with in vivo sizing, was relatively high (0.056 N/mm), which correlates well with the collapse pressure of 0.17 bars. Vessel wall adaptation was harmonic and caused no straightening of the vessel after clinical application. Conclusion: Because of its structure, the novel CGUARD EPS stent is characterized by a high flexibility combined with a high radial force and very good plaque coverage. These first clinical results demonstrate a very safe implantation behavior without any stroke up to 6 months after the procedure.

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A Rare Nitinol Double-Layer Micromesh Carotid Stent Complication: Late Thrombosis—First Case Reported in Literature

Annals of Vascular Surgery ◽

10.1016/j.avsg.2018.10.030 ◽

2019 ◽

Vol 58 ◽

pp. 380.e5-380.e8 ◽

Cited By ~ 1

Author(s):

Gianfranco Varetto ◽

Edoardo Frola ◽

Lorenzo Gibello ◽

Flavia Spalla ◽

Paolo Garneri ◽

...

Keyword(s):

Double Layer ◽

Carotid Stent ◽

First Case ◽

Late Thrombosis

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Mechanical Behavior of Natural Fiber-Based Bi-Directional Corrugated Lattice Sandwich Structure

Materials ◽

10.3390/ma11122578 ◽

2018 ◽

Vol 11 (12) ◽

pp. 2578 ◽

Cited By ~ 4

Author(s):

Shuguang Li ◽

Yanxia Feng ◽

Mengyuan Wang ◽

Yingcheng Hu

Keyword(s):

Compressive Strength ◽

Mechanical Behavior ◽

Young’S Modulus ◽

Double Layer ◽

Young's Modulus ◽

Layer Structure ◽

Core Layer ◽

The Core ◽

Fiber Angle ◽

Double Layer Structure

In this study, 11 kinds of composite material were prepared, and the compression behavior of a bi-directional corrugated lattice sandwich structure prepared using jute fiber and epoxy resin was explored. The factors affecting the mechanical behavior of single and double-layer structures were studied separately. The results shows that the fiber angle, length-to-diameter ratio of the struts, and the type of fiber cloth have the most significant influence on the mechanical behavior of the single-layer lattice structure when preparing the core layer. When the fiber angle of the core layer jute/epoxy prepreg is (90/90) the compressive strength and Young’s modulus are 83.3% and 60.0% higher than the fiber angle of (45/45). The configuration of the core and the presence of the intermediate support plate of the double-layer structure have a large influence on the compression performance of the two-layer structure. After the configuration was optimized, the compressive strength and Young’s modulus were increased by 40.0% and 28.9%, respectively. The presence of the intermediate support plate increases the compressive strength, and Young’s modulus of the double-layer structure by 75.0% and 26.6%, respectively. The experimental failure is dominated by the buckling, fracture, and delamination of the core struts.

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Application of TEM to Deformation, Wear, and Fracture of Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052377 ◽

1974 ◽

Vol 32 ◽

pp. 472-473

Author(s):

B. J. Hockey

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Mechanical Behavior ◽

Brittle Materials ◽

High Temperature Strength ◽

Wide Range ◽

Corrosive Environments ◽

Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

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