A non-invasive estimation technique to determine dielectric properties of multilayer human tissue

2021 ◽  
Author(s):  
Soumyadeep Das ◽  
Adarsh Singh ◽  
Rajarshi RoyChowdhury ◽  
Debasis Mitra
Keyword(s):  
Dielectric Properties ◽  
Human Tissue ◽  
Estimation Technique ◽  
Non Invasive

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.

Enhancements to the Non-Invasive Current Estimation Technique Through Ground Isolation

2021 ◽  
Author(s):  
Chad M. Smutzer ◽  
Jordan R. Keuseman ◽  
Christopher K. White ◽  
Clifton R. Haider ◽  
Barry K. Gilbert
Keyword(s):  
Estimation Technique ◽  
Non Invasive ◽  
Current Estimation

scholarly journals Development and validation of a MRgHIFU non-invasive tissue acoustic property estimation technique

2016 ◽  
Vol 32 (7) ◽  
pp. 723-734 ◽  
Author(s):  
Sara L. Johnson ◽  
Christopher Dillon ◽  
Henrik Odéen ◽  
Dennis Parker ◽  
Douglas Christensen ◽  
...  
Keyword(s):  
Acoustic Property ◽  
Estimation Technique ◽  
Non Invasive ◽  
Property Estimation ◽  
Development And Validation

scholarly journals Conformal and Disposable Antenna-Based Sensor for Non-Invasive Sweat Monitoring

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4088 ◽  
Author(s):  
Angie Eldamak ◽  
Elise Fear
Keyword(s):  
Dielectric Properties ◽  
Patch Antenna ◽  
Low Cost ◽  
Salt Solutions ◽  
Paper Substrate ◽  
Antenna Structure ◽  
Non Invasive ◽  
Nacl Concentration ◽  
Artificial Sweat ◽  
Cellulose Filter

This paper presents a feasibility study for a non-wearable, conformal, low cost, and disposable antenna-based sensor for non-invasive hydration monitoring using sweat. It is composed of a patch antenna implemented on a cellulose filter paper substrate and operating in the range 2–4 GHz. The paper substrate can absorb liquids, such as sweat on the skin, through two slots incorporated within the antenna structure. Thus, the substrate dielectric properties are altered according to the properties of the absorbed liquid. Changes in reflection-based measurements are used to analyze salt solutions and artificial sweat, specifically the amount of sampled solution and the sodium chloride (NaCl) concentration. Using the shift in resonant frequency and magnitude of the reflection coefficient, NaCl concentrations in the range of 8.5–200 mmol/L, representing different hydration states, are detected. The measurements demonstrate the feasibility of using microwave based measurements for hydration monitoring using sweat.

scholarly journals Longitudinal and Transverse Relaxivity Analysis of Native Ferritin and Magnetoferritin at 7 T MRI

2021 ◽  
Vol 22 (16) ◽  
pp. 8487
Author(s):  
Oliver Strbak ◽  
Lucia Balejcikova ◽  
Martina Kmetova ◽  
Jan Gombos ◽  
Jozef Kovac ◽  
...  
Keyword(s):  
Neurodegenerative Disorders ◽  
Strong Correlation ◽  
Human Tissue ◽  
Model System ◽  
Iron Loading ◽  
Complementary Information ◽  
Non Invasive ◽  
Relaxation Parameters ◽  
Mri Diagnosis ◽  
Mineral Core

Magnetite mineralization in human tissue is associated with various pathological processes, especially neurodegenerative disorders. Ferritin’s mineral core is believed to be a precursor of magnetite mineralization. Magnetoferritin (MF) was prepared with different iron loading factors (LFs) as a model system for pathological ferritin to analyze its MRI relaxivity properties compared to those of native ferritin (NF). The results revealed that MF differs statistically significantly from NF, with the same LF, for all studied relaxation parameters at 7 T: r1, r2, r2*, r2/r1, r2*/r1. Distinguishability of MF from NF may be useful in non-invasive MRI diagnosis of pathological processes associated with iron accumulation and magnetite mineralization (e.g., neurodegenerative disorders, cancer, and diseases of the heart, lung and liver). In addition, it was found that MF samples possess very strong correlation and MF’s relaxivity is linearly dependent on the LF, and the transverse and longitudinal ratios r2/r1 and r2*/r1 possess complementary information. This is useful in eliminating false-positive hypointensive artefacts and diagnosis of the different stages of pathology. These findings could contribute to the exploitation of MRI techniques in the non-invasive diagnosis of iron-related pathological processes in human tissue.

scholarly journals Bimodal microwave and ultrasound phantoms for non-invasive clinical imaging

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Enrique Villa ◽  
Natalia Arteaga-Marrero ◽  
Javier González-Fernández ◽  
Juan Ruiz-Alzola
Keyword(s):  
Dielectric Properties ◽  
Soft Tissues ◽  
Sucrose Concentration ◽  
Acoustic Properties ◽  
Gelling Agent ◽  
Non Invasive ◽  
Significant Performance ◽  
Cole Model ◽  
Ultrasound Applications

AbstractA precise and thorough methodology is presented for the design and fabrication of bimodal phantoms to be used in medical microwave and ultrasound applications. Dielectric and acoustic properties of human soft tissues were simultaneously mimicked. The phantoms were fabricated using polyvinyl alcohol cryogel (PVA-C) as gelling agent at a 10% concentration. Sucrose was employed to control the dielectric properties in the microwave spectrum, whereas cellulose was used as acoustic scatterer for ultrasound. For the dielectric properties at microwaves, a mathematical model was extracted to calculate the complex permittivity of the desired mimicked tissues in the frequency range from 500 MHz to 20 GHz. This model, dependent on frequency and sucrose concentration, was in good agreement with the reference Cole–Cole model. Regarding the acoustic properties, the speed of sound and attenuation coefficient were employed for validation. In both cases, the experimental data were consistent with the corresponding theoretical values for soft tissues. The characterization of these PVA-C phantoms demonstrated a significant performance for simultaneous microwave and ultrasound operation. In conclusion, PVA-C has been validated as gelling agent for the fabrication of complex multimodal phantoms that mimic soft tissues providing a unique tool to be used in a range of clinical applications.

Dielectric properties of MSWI bottom ash for non-invasive monitoring of moisture

2013 ◽  
Vol 185 (8) ◽  
pp. 7053-7063 ◽  
Author(s):  
Aamir Ilyas ◽  
Magnus Persson ◽  
Martijn van Praagh
Keyword(s):  
Dielectric Properties ◽  
Bottom Ash ◽  
Invasive Monitoring ◽  
Non Invasive ◽  
Mswi Bottom Ash

scholarly journals Ultra-Wideband Temperature Dependent Dielectric Spectroscopy of Porcine Tissue and Blood in the Microwave Frequency Range

Sensors ◽  
2019 ◽  
Vol 19 (7) ◽  
pp. 1707 ◽  
Author(s):  
Sebastian Ley ◽  
Susanne Schilling ◽  
Ondrej Fiser ◽  
Jan Vrba ◽  
Jürgen Sachs ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Microwave Frequency ◽  
Ultra Wideband ◽  
Frequency Range ◽  
Temperature Dependent ◽  
Hyperthermia Treatment ◽  
Non Invasive ◽  
Animal Liver ◽  
Cole Model ◽  
Diagnostic Technologies

The knowledge of frequency and temperature dependent dielectric properties of tissue is essential to develop ultra-wideband diagnostic technologies, such as a non-invasive temperature monitoring system during hyperthermia treatment. To this end, we characterized the dielectric properties of animal liver, muscle, fat and blood in the microwave frequency range from 0.5 GHz to 7 GHz and in the temperature range between 30 °C and 50 °C. The measured data were modeled to a two-pole Cole-Cole model and a second-order polynomial was introduced to fit the Cole-Cole parameters as a function of temperature. The parametric model provides access to the dielectric properties of tissue at any frequency and temperature in the specified range.

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