Simulation of a Strategy for the Assessment of Damage in Human Bones by Using FEM and Signal Processing

2011 ◽  
Vol 488-489 ◽  
pp. 371-374
Author(s):  
Marco Miniaci ◽  
Alessandro Marzani ◽  
Erasmo Viola
Keyword(s):  
Mechanical Properties ◽  
Signal Processing ◽  
Guided Waves ◽  
Metabolic Diseases ◽  
Invasive Technique ◽  
Future Studies ◽  
Damage Level ◽  
Non Invasive ◽  
Human Bones ◽  
Non Destructive

The aim of this work is to propose a non-invasive technique aimed at assessing the evolution of damage in elongated bones that could be caused, for instance, by metabolic diseases. The technique exploits signals related to mechanical guided waves traveling along the bone to characterize its mechanical properties in a total non-destructive manner. Such properties can be used as an indicator of the damage level present in the bone. The preliminary results motivate future studies

Fertilization state ofAscaris suumdetermined by electrorotation

2006 ◽  
Vol 80 (1) ◽  
pp. 25-31 ◽  
Author(s):  
C. Dalton ◽  
A.D. Goater ◽  
H.V. Smith
Keyword(s):  
Dielectric Properties ◽  
Physicochemical Properties ◽  
Parasitic Nematode ◽  
Invasive Technique ◽  
Non Invasive ◽  
Egg Morphology ◽  
Parasite Biology ◽  
Response Modelling ◽  
Non Destructive ◽  
Insight Into

AbstractElectrorotation is a non-invasive technique that is capable of detecting changes in the morphology and physicochemical properties of microorganisms. The first detailed electrorotation study of the egg (ovum) of a parasitic nematode, namelyAscaris suumis described to show that electrorotation can rapidly differentiate between fertilized and non-fertilized eggs. Support for this conclusion is by optical microscopy of egg morphology, and also from modelling of the electrorotational response. Modelling was used to determine differences in the dielectric properties of the unfertilized and fertilized eggs, and also to investigate specific differences in the spectra of fertilized eggs only, potentially reflecting embryogenesis. The potential of electrorotation as an investigative tool is shown, as undamaged eggs can be subjected to further non-destructive and destructive techniques, which could provide further insight into parasite biology and epidemiology.

Non-Destructive and Non-Invasive Assessment of Mechanical Properties in Heart Valve Tissue Engineering

2008 ◽  
Author(s):  
Jeroen Kortsmit ◽  
Niels J. B. Driessen ◽  
Marcel C. M. Rutten ◽  
Frank P. T. Baaijens
Keyword(s):  
Mechanical Properties ◽  
Heart Valve ◽  
Heart Valves ◽  
Tensile Tests ◽  
Numerical Approach ◽  
Non Invasive ◽  
Indentation Tests ◽  
Tissue Engineered Heart Valves ◽  
End Stage ◽  
Non Destructive

Despite recent progress, mechanical properties of tissue engineered heart valves still lack mechanical strength compared to native aortic valves [1]. Although cyclic tissue straining in bioreactor systems is known to enhance tissue formation [2], specific optimal loading protocols have not yet been defined. To get a better insight in the effects of mechanical loading on tissue development, mechanical behavior of tissue constructs should be monitored and controlled during culture. However, currently used methods for mechanical characterization (e.g. tensile tests, indentation tests) are destructive and can therefore only be performed at the end stage of tissue culture. An experimental-numerical approach was previously proposed by which leaflet deformation was assessed during culture in a bioreactor system, real-time and non-invasively [3]. Further development of this approach now enables a non-invasive and non-destructive assessment of mechanical properties of engineered heart valve leaflets.

scholarly journals Infrared thermography analysis with a low-cost camera in plaster sculptures of museum collections

2021 ◽  
Vol 20 ◽  
pp. 7-15
Author(s):  
Rui Bordalo ◽  
Salomé Carvalho ◽  
José Guilherme Abreu ◽  
Eduarda Vieira
Keyword(s):  
Infrared Thermography ◽  
Layer Structure ◽  
Low Cost ◽  
Invasive Technique ◽  
Museum Collections ◽  
Non Invasive ◽  
Large Structures ◽  
Active Infrared Thermography ◽  
Non Destructive ◽  
Suitable Technique

Infrared thermography (IRT) is a non-destructive and non-invasive technique that provides the possibility to investigate the surface of sculptures for the detection of subsurface features and anomalies such as delamination, layer structure, fillings, and defects. IRT has been widely used in buildings and large structures, as well as in works of art such as bronze sculptures and paintings. This article describes the application of active infrared thermography, using a portable low-cost IRT camera, in the examination of plaster sculptures, a material where it has not yet been applied to. In particular, it was used in two plaster sculptures by 19th-century Portuguese artist Soares dos Reis, within a wider project (GEO-SR) aimed at the study of his work. The results indicate that thermography is a suitable technique with a great potential to detect alterations under the surface of plaster, revealing a new look into its manufacturing and conservation.

scholarly journals A MECANOGRAFIA COMO TÉCNICA NÃO-INVASIVA PARA O ESTUDO DA FUNÇÃO MUSCULAR

2007 ◽  
Vol 5 (10) ◽  
pp. 15-20 ◽  
Author(s):  
Marco Aurélio Vaz ◽  
Walter Herzog
Keyword(s):  
Mechanical Properties ◽  
Skeletal Muscle ◽  
Motor Control ◽  
Motor Units ◽  
Invasive Technique ◽  
Muscular System ◽  
Tetanic Contraction ◽  
Activation Patterns ◽  
Non Invasive ◽  
Technological Limitations

A mecanomiografia (MMG) é uma técnica nao-invasiva que registra as vibrações ou sons produzidos pelo músculo esquelético ao se contrair. As primeiras observações da existência destas vibrações foi feita há mais de trezentos anos, mas limitações tecnológicas fizeram com que a MMG só recebesse atenção nas últimas décadas. A teoria mais aceita para explicar o mecanismo dessas vibrações é a de que elas são produzidas pela contração tetânica incompleta das unidades motoras. O sinal MMG fornece informações relativas aos padrões de ativação elétrica e ao comportamento mecânico do músculo. Essa técnica pode ser utilizada para estudar as propriedades mecânicas do sistema muscular, o controle motor, a fadiga muscular entre outras aplicações. Mecanomyography (MMG) is a non-invasive technique that records the vibrations or sounds produced by skeletal muscle during contraction. The first observations of the existence of these vibrations/sounds occurred more than three hundred years ago, but due to technological limitations the MMG only received attention in the last few decades. The most accepted theory to the mechanism of these vibrations is that they are produced by the unfused tetanic contraction of motor units. The MMG signal provides information related both to the activation patterns and to the mechanical behavior of skeletal muscle. This technique might be used to study the mechanical properties of the muscular system, motor control, muscle fatigue amongst other applications.

USING DOPPLER TO ASSESS THE FETAL HEALTH FOR THE PREDICTION OF GESTATIONAL OUTCOME

2014 ◽  
pp. 9-18
Author(s):  
Thi Linh Giang Truong ◽  
Vu Quoc Huy Nguyen
Keyword(s):  
Middle Cerebral Artery ◽  
Cerebral Artery ◽  
Umbilical Artery ◽  
Functional Method ◽  
Invasive Technique ◽  
Routine Practice ◽  
Fetal Health ◽  
Uterine Arteries ◽  
Non Invasive ◽  
Key Words Doppler

Background: Assessment of fetal health plays the most important role in prenatal care because of influence of the prediction of gestational outcome. One of the main aims of routine antenatal care is to identify the ‘ at risk ‘ fetus in order to apply clinical interventions which could results in reduced perinatal morbidity and mortality. Doppler ultrasound is a non invasive technique whereby the movement of blood is studied by detecting the change in frequence of reflected sound, Doppler blood flow velocity waves form of fetal side (umbilical artery, middle cerebral artery ...) and maternal side ( uterine arteries) are discussed and monograms for routine practice are presented. Recently this method is important tool for qualifying high risk pregnancies and help early forecasts the health of the babies and mothers disorder. Doppler sonography in obstetrics is a widely accepted functional method of examining the prediction of gestational outcome. Key words: Doppler, umbilical artery, middle cerebral artery, uterine arteries

scholarly journals A Generalized Approach for Evaluating the Mechanical Properties of Polymer Nanocomposites Reinforced with Spherical Fillers

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 830
Author(s):  
Julio Cesar Martinez-Garcia ◽  
Alexandre Serraïma-Ferrer ◽  
Aitor Lopeandía-Fernández ◽  
Marco Lattuada ◽  
Janak Sapkota ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polymeric Nanocomposites ◽  
Mechanical Reinforcement ◽  
Future Studies ◽  
Three Phase ◽  
Theoretical Predictions ◽  
Filler Network ◽  
New Research ◽  
Good Agreement ◽  
Research Avenue

In this work, the effective mechanical reinforcement of polymeric nanocomposites containing spherical particle fillers is predicted based on a generalized analytical three-phase-series-parallel model, considering the concepts of percolation and the interfacial glassy region. While the concept of percolation is solely taken as a contribution of the filler-network, we herein show that the glassy interphase between filler and matrix, which is often in the nanometers range, is also to be considered while interpreting enhanced mechanical properties of particulate filled polymeric nanocomposites. To demonstrate the relevance of the proposed generalized equation, we have fitted several experimental results which show a good agreement with theoretical predictions. Thus, the approach presented here can be valuable to elucidate new possible conceptual routes for the creation of new materials with fundamental technological applications and can open a new research avenue for future studies.

scholarly journals Non-Invasive Testing of Physical Systems Using Topological Sensitivity

2021 ◽  
Vol 11 (3) ◽  
pp. 1341
Author(s):  
María Higuera ◽  
José M. Perales ◽  
María-Luisa Rapún ◽  
José M. Vega
Keyword(s):  
Lamb Waves ◽  
General Purpose ◽  
Mathematical Tool ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Topological Sensitivity ◽  
Physical Systems ◽  
Non Invasive ◽  
Active Infrared Thermography ◽  
Non Destructive

A review of available results on non-destructive testing of physical systems, using the concept of topological sensitivity, is presented. This mathematical tool estimates the sensitivity of a set of measurements in some given sensors, distributed along the system, to defects/flaws that produce a degradation of the system. Such degradation manifests itself on the properties of the system. The good performance of this general purpose post-processing method is reviewed and illustrated in some applications involving non-destructive testing. These applications include structural health monitoring, considering both elastodynamic ultrasonic guided Lamb waves and active infrared thermography. Related methods can also be used in other fields, such as diagnosis/prognosis of engineering devices, which is also considered.

scholarly journals Prevalence and Photobiology of Photosynthetic Dinoflagellate Endosymbionts in the Nudibranch Berghia stephanieae

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2200
Author(s):  
Ruben X. G. Silva ◽  
Paulo Cartaxana ◽  
Ricardo Calado
Keyword(s):  
Food Deprivation ◽  
Photosynthetic Efficiency ◽  
Rapid Decrease ◽  
Complete Loss ◽  
Symbiotic Association ◽  
Non Invasive ◽  
Sea Slugs ◽  
Non Destructive ◽  
Over Time

Berghia stephanieae is a stenophagous sea slug that preys upon glass anemones, such as Exaiptasia diaphana. Glass anemones host photosynthetic dinoflagellate endosymbionts that sea slugs ingest when consuming E. diaphana. However, the prevalence of these photosynthetic dinoflagellate endosymbionts in sea slugs appears to be short-lived, particularly if B.stephanieae is deprived of prey that host these microalgae (e.g., during bleaching events impacting glass anemones). In the present study, we investigated this scenario, along with food deprivation, and validated the use of a non-invasive and non-destructive approach employing chlorophyll fluorescence as a proxy to monitor the persistence of the association between sea slugs and endosymbiotic photosynthetic dinoflagellates acquired through the consumption of glass anemones. Berghia stephanieae deprived of a trophic source hosting photosynthetic dinoflagellate endosymbionts (e.g., through food deprivation or by feeding on bleached E. diaphana) showed a rapid decrease in minimum fluorescence (Fo) and photosynthetic efficiency (Fv/Fm) when compared to sea slugs fed with symbiotic anemones. A complete loss of endosymbionts was observed within 8 days, confirming that no true symbiotic association was established. The present work opens a new window of opportunity to rapidly monitor in vivo and over time the prevalence of associations between sea slugs and photosynthetic dinoflagellate endosymbionts, particularly during bleaching events that prevent sea slugs from incorporating new microalgae through trophic interactions.

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