Microstructural Failure Physics for Structural Failure Prognosis and Diagnosis

2003 ◽  
Author(s):  
Donald A. Shockey ◽  
Jeffrey W. Simons ◽  
Takao Kobayashi ◽  
Dennis Grishin
Keyword(s):  
Structural Failure ◽  
Failure Prognosis

Surface Modification of Poly(Vinylchloride) for Manufacturing Advanced Catheters

2020 ◽  
Vol 27 (10) ◽  
pp. 1616-1633 ◽  
Author(s):  
Oana Cristina Duta ◽  
Aurel Mihail Ţîţu ◽  
Alexandru Marin ◽  
Anton Ficai ◽  
Denisa Ficai ◽  
...  
Keyword(s):  
Surface Modification ◽  
Chemical Modification ◽  
Medical Devices ◽  
Low Cost ◽  
Physical And Mechanical Properties ◽  
Polymeric Materials ◽  
Modern Medicine ◽  
Structural Failure ◽  
Chemical Grafting ◽  
One Step

Polymeric materials, due to their excellent physicochemical properties and versatility found applicability in multiples areas, including biomaterials used in tissue regeneration, prosthetics (hip, artificial valves), medical devices, controlled drug delivery systems, etc. Medical devices and their applications are very important in modern medicine and the need to develop new materials with improved properties or to improve the existent materials is increasing every day. Numerous reasearches are activated in this domain in order to obtain materials/surfaces that does not have drawbacks such as structural failure, calcifications, infections or thrombosis. One of the most used material is poly(vinylchloride) (PVC) due to its unique properties, availability and low cost. The most common method used for obtaining tubular devices that meet the requirements of medical use is the surface modification of polymers without changing their physical and mechanical properties, in bulk. PVC is a hydrophobic polymer and therefore many research studies were conducted in order to increase the hydrophilicity of the surface by chemical modification in order to improve biocompatibility, to enhance wettability, reduce friction or to make lubricious or antimicrobial coatings. Surface modification of PVC can be achieved by several strategies, in only one step or, in some cases, in two or more steps by applying several techniques consecutively to obtain the desired modification / performances. The most common processes used for modifying the surface of PVC devices are: plasma treatment, corona discharge, chemical grafting, electric discharge, vapour deposition of metals, flame treatment, direct chemical modification (oxidation, hydrolysis, etc.) or even some physical modification of the roughness of the surface.

Common Comorbidities that Alter Heart Failure Prognosis - shaping new thinking for practice.

2020 ◽  
Vol 16 ◽  
Author(s):  
Pupalan Iyngkaran ◽  
Merlin Thomas ◽  
John D Horowitz ◽  
Paul Komesaroff ◽  
Michael Jelinek ◽  
...  
Keyword(s):  
Heart Failure ◽  
Self Management ◽  
Community Practice ◽  
Elderly Age ◽  
Medical Specialists ◽  
General Internal ◽  
Allied Health Care ◽  
Speciality Training ◽  
New Thinking ◽  
Failure Prognosis

: At least half of all heart failure (CHF) patients will have a comorbidity that could be undertreated, requires additional speciality input and/or polypharmacy. These patients are then at risk from iatrogenic and disease related complications and readmissions if not closely supervised. Common comorbidities of relevance are cardiorenal and cardiometabolic syndromes (DM, obesity, OSA), chronic airways disease, elderly age and accompanying therapeutic optimisation. The structure of community practice often leaves primary, speciality and allied health care in silos. For example, cardiology speciality training in Australia creates excellent sub-specialists to deliver on the diagnostics and therapeutic advances. A casualty of this process has been gradual alienation of general cardiology towards general internal medical specialists and GP's. The consequences are largely noticed in community practice. The issue are compounded by suboptimal communication of information. This review explores these issues from a cardiology sub-speciality lens, firstly cross speciality areas important for cardiologist to maintain their skill and finally a brief overview of disease management and identifying game changing common denominators such as endothelial dysfunction and self-management.

Assessment of acute heart failure prognosis: the promising role of prognostic models and biomarkers

2021 ◽  
Author(s):  
Nikolaos P. E. Kadoglou ◽  
John Parissis ◽  
Apostolos Karavidas ◽  
Ioannis Kanonidis ◽  
Marialena Trivella
Keyword(s):  
Heart Failure ◽  
Acute Heart Failure ◽  
Prognostic Models ◽  
Failure Prognosis

scholarly journals Biomimetic recombinant of red blood cell membranes for improved photothermal therapy

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Pengkai Wu ◽  
Xing Jiang ◽  
Shuai Yin ◽  
Ying Yang ◽  
Tianqing Liu ◽  
...  
Keyword(s):  
Immune Escape ◽  
Green Technology ◽  
Structural Failure ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Coated Nanoparticles ◽  
Rbc Membrane ◽  
Delivery Platform ◽  
Red Blood Cell Membranes ◽  
Endogenous Proteins ◽  
Active Substances

Abstract Background RBC membrane derived nanoparticles (NPs) represent an emerging platform with prolonged circulation capacity for the delivery of active substances. For functionalize derived RBCs NPs, various strategies, such as biomimetic rebuilding of RBCs, chemical modification or inserting ligands, have been carried out to improve their performance. However, one potential adverse effect for these methods is the structural failure of membrane proteins, consequently affecting its original immune escape function. Results In this study, we reported a green technology of “disassembly-reassembly” to prepare biomimetic reconstituted RBCs membrane (rRBCs) by separating the endogenous proteins and lipids from nature RBC membrane. IR780 iodide was used as a pattern drug to verify the property and feasibility of rRBCs by constructing IR780@rRBC NPs with IR780@RBC NPs and free IR780 as controls. The results demonstrated the superiority of IR780@rRBC NPs in toxicity, stability, pharmacokinetics and pharmacodynamics compared with IR780@rRBC and free IR780. Conclusions The reported “disassembly-reassembly” strategy shows great potential to produce controllable and versatile rRBC membrane-inspired delivery platform, which may be used to overcome the deficiency of functionalization in cell membrane coated nanoparticles . Graphic abstract

scholarly journals Experimental-numerical study on the structural failure of concrete sewer pipes

2021 ◽  
Vol 116 ◽  
pp. 104075
Author(s):  
I.C. Scheperboer ◽  
R.A. Luimes ◽  
A.S.J. Suiker ◽  
E. Bosco ◽  
F.H.L.R. Clemens
Keyword(s):  
Numerical Study ◽  
Structural Failure ◽  
Sewer Pipes

scholarly journals Special Issue “Advances in Machine Learning and Deep Learning Based Machine Fault Diagnosis and Prognosis”

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 532
Author(s):  
Mohand Djeziri ◽  
Marc Bendahan
Keyword(s):  
Machine Learning ◽  
Deep Learning ◽  
Fault Diagnosis ◽  
Special Issue ◽  
Maintenance Strategies ◽  
Corrective Maintenance ◽  
Diagnosis And Prognosis ◽  
Machine Fault Diagnosis ◽  
Failure Prognosis ◽  
Fault Diagnosis And Prognosis

Fault diagnosis and failure prognosis aim to reduce downtime of the systems and to optimise their performance by replacing preventive and corrective maintenance strategies with predictive or conditional ones [...]

Thermomechanical Modeling of Laser Spot Welded Solar Absorbers

2015 ◽  
Vol 137 (1) ◽  
Author(s):  
L. A. Spyrou ◽  
N. Aravas
Keyword(s):  
Spot Welding ◽  
Laser Spot ◽  
Structural Failure ◽  
Absorber Plate ◽  
Solar Absorber ◽  
Solar Absorbers ◽  
Laser Spot Welding ◽  
Thermomechanical Modeling ◽  
Different Levels ◽  
Flattening Process

A finite element (FE) approach is developed to investigate the laser spot welding (LSW) of flat-plate solar absorbers and the stress and distortion fields that develop after fabrication and during operation. Numerical calculations at two different levels are carried out. At a microscopic scale, the details of a spot weld are analyzed. At a macroscopic level, a global approach is used to simulate the joining of the pipeline to the absorber plate and the “restoration” (flattening) process of the absorber. The simulated welding-induced distortion is compared with experimental measurements. The thermomechanical behavior of a solar absorber under working conditions is also studied and operational stresses and the critical locations for structural failure are reported.

SIMP for Complex Structures

2016 ◽  
Vol 846 ◽  
pp. 535-540
Author(s):  
David J. Munk ◽  
David W. Boyd ◽  
Gareth A. Vio
Keyword(s):  
Natural Frequencies ◽  
Dynamic Loads ◽  
Topology Optimisation ◽  
Complex Structures ◽  
Structural Failure ◽  
Frequency Range ◽  
Aerodynamic Loading ◽  
Frequency Excitation ◽  
Wing Structure ◽  
Lifting Surfaces

Designing structures with frequency constraints is an important task in aerospace engineering. Aerodynamic loading, gust loading, and engine vibrations all impart dynamic loads upon an airframe. To avoid structural resonance and excessive vibration, the natural frequencies of the structure must be shifted away from the frequency range of any dynamic loads. Care must also be taken to ensure that the modal frequencies of a structure do not coalesce, which can lead to dramatic structural failure. So far in industry, no aircraft lifting surfaces are designed from the ground up with frequency optimisation as the primary goal. This paper will explore computational methods for achieving this task.This paper will present a topology optimisation algorithm employing the Solid Isotropic Microstructure with Penalisation (SIMP) method for the design of an optimal aircraft wing structure for rejection of frequency excitation.

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