scholarly journals Theoretical Simulation of the Near-Field Probe for Non-Invasive Measurements on Planar Layers with Biological Characteristics

2020 ◽  
Vol 7 (4) ◽  
pp. 149
Author(s):  
Aleksandr Gorst ◽  
Kseniya Zavyalova ◽  
Vladimir Yakubov ◽  
Aleksandr Mironchev ◽  
Andrey Zapasnoy
Keyword(s):  
Blood Glucose Concentration ◽  
Near Field ◽  
Plane Layer ◽  
Biological Tissues ◽  
Wide Frequency Range ◽  
Probe Design ◽  
Depth Of Penetration ◽  
Theoretical Simulation ◽  
Non Invasive ◽  
Useful Signal

The article presents the design of the near-field probe, which is a combined emitter (a combination of a symmetric dipole and an annular frame). The design of the probe allows forming a prolonged zone of the near-field. This effect can be used for in-depth penetration of the field in media with high absorption, without loss of information. Particular attention in this article is given to a detailed study of the interaction of the field created by this probe on plane-layered biological media. A theoretical analysis of the interaction of the electromagnetic field was carried out in a wide frequency band with a model plane-layer biological medium containing blood vessels of shallow depth using the proposed probe design. Conclusions are drawn about the depth of penetration of a useful signal into different media-analogs of biological tissue. This study is necessary to consider the possibility of using this probe for non-invasive measurements of blood glucose concentration. The studies were carried out using numerical simulation in the CST (Computer Simulation Technology) Microwave Studio environment. All biological tissues were simulated over a wide frequency range from 10 MHz to 10 GHz.

scholarly journals Non-Invasive Determination of Blood Glucose Concentration Using a Near-Field Sensor

Proceedings ◽  
2020 ◽  
Vol 60 (1) ◽  
pp. 1
Author(s):  
Kseniya Zavyalova ◽  
Aleksandr Gorst ◽  
Aleksandr Mironchev
Keyword(s):  
Electromagnetic Waves ◽  
Blood Glucose Concentration ◽  
Flexible Substrate ◽  
Near Field ◽  
Slot Antenna ◽  
Non Invasive ◽  
High Penetration ◽  
Field Sensor ◽  
Small Change ◽  
5 Ghz

This article demonstrates a model of a near-field sensor, which is a combined slot antenna based on a flexible substrate RO3003. It is shown that the sensor has a high penetration of electromagnetic waves into highly absorbing media due to the length of the near field. In addition, it has a small size (diameter the sensor is 25 mm, thickness 0.76 mm). The simplified model of a hand simplified with a shallow vein depth was constructed. This model based on the experimentally obtained data of dielectric constant for glucose concentrations of 1.2–10 mmol/l. The simulation results, carried out in the frequency range 0.5–5 GHz, showed the possibility of determining a small change in blood sugar level from the reflected signal data.

scholarly journals Imaging with Local Speckle Intensity Correlations: Theory and Practice

2021 ◽  
Vol 40 (3) ◽  
pp. 1-22
Author(s):  
Marina Alterman ◽  
Chen Bar ◽  
Ioannis Gkioulekas ◽  
Anat Levin
Keyword(s):  
Near Field ◽  
Biological Tissues ◽  
Computational Imaging ◽  
Theory And Practice ◽  
Fluorescent Imaging ◽  
Light Sources ◽  
Far Field ◽  
Scattering Layer ◽  
Speckle Patterns ◽  
Field Imaging

Recent advances in computational imaging have significantly expanded our ability to image through scattering layers such as biological tissues by exploiting the auto-correlation properties of captured speckle intensity patterns. However, most experimental demonstrations of this capability focus on the far-field imaging setting, where obscured light sources are very far from the scattering layer. By contrast, medical imaging applications such as fluorescent imaging operate in the near-field imaging setting, where sources are inside the scattering layer. We provide a theoretical and experimental study of the similarities and differences between the two settings, highlighting the increased challenges posed by the near-field setting. We then draw insights from this analysis to develop a new algorithm for imaging through scattering that is tailored to the near-field setting by taking advantage of unique properties of speckle patterns formed under this setting, such as their local support. We present a theoretical analysis of the advantages of our algorithm and perform real experiments in both far-field and near-field configurations, showing an order-of magnitude expansion in both the range and the density of the obscured patterns that can be recovered.

Estimation of Transformer Winding Capacitances through Frequency Response Analysis – An Experimental Investigation

2013 ◽  
Vol 14 (6) ◽  
pp. 549-559 ◽  
Author(s):  
Krupa Shah ◽  
K. Ragavan
Keyword(s):  
Frequency Response ◽  
Wide Frequency Range ◽  
Response Analysis ◽  
Voltage Distribution ◽  
Response Data ◽  
Non Invasive ◽  
Transformer Winding ◽  
Invasive Method ◽  
Ladder Network ◽  
Good Agreement

Abstract This article focuses on developing a non-invasive method for determining capacitances using frequency response data. The proposed methodology involves acquiring driving-point impedance of the winding under consideration over wide frequency range. With certain terminal conditions and using the terminal impedance measured at specific frequencies, input and shunt capacitances are determined. For the purpose of estimating series capacitance of the winding, an algorithm is proposed. To demonstrate the capability of the method, initially model coils that have provisions for connecting external capacitances are considered. Then, it is found that the estimated values of capacitances are nearly same as those of connected capacitances. The method is, then, extended to transformer winding, and a capacitive ladder network is constructed. To assess the accuracy of estimation, capacitive voltage distribution is utilized. That is, the voltage distribution in the winding is compared with that of synthesized circuit. A good agreement between those data reveals that the estimated capacitance values are accurate.

scholarly journals Remote-controlled insect navigation using plasmonic nanotattoos

2020 ◽  
Author(s):  
Sirimuvva Tadepalli ◽  
Sisi Cao ◽  
Debajit Saha ◽  
Keng-Ku Liu ◽  
Alex Chen ◽  
...  
Keyword(s):  
Region Of Interest ◽  
Biological Tissues ◽  
Plasmonic Nanostructures ◽  
Insect Navigation ◽  
Non Invasive ◽  
Limiting Step ◽  
Engineering Problems ◽  
Complex Engineering ◽  
Recognition Elements ◽  
Insect Antenna

Developing insect cyborgs by integrating external components (optical, electrical or mechanical) with biological counterparts has a potential to offer elegant solutions for complex engineering problems.1 A key limiting step in the development of such biorobots arises at the nano-bio interface, i.e. between the organism and the nano implant that offers remote controllability.1,2 Often, invasive procedures are necessary that tend to severely compromise the navigation capabilities as well as the longevity of such biorobots. Therefore, we sought to develop a non-invasive solution using plasmonic nanostructures that can be photoexcited to generate heat with spatial and temporal control. We designed a ‘nanotattoo’ using silk that can interface the plasmonic nanostructures with a biological tissue. Our results reveal that both structural and functional integrity of the biological tissues such as insect antenna, compound eyes and wings were preserved after the attachment of the nanotattoo. Finally, we demonstrate that insects with the plasmonic nanotattoos can be remote controlled using light and integrated with functional recognition elements to detect the chemical environment in the region of interest. In sum, we believe that the proposed technology will play a crucial role in the emerging fields of biorobotics and other nano-bio applications.

A Simple Miniature Ultrawideband Magnetic Field Probe Design for Magnetic Near-Field Measurements

2016 ◽  
Vol 64 (12) ◽  
pp. 5459-5465 ◽  
Author(s):  
Zhaowen Yan ◽  
Jianwei Wang ◽  
Wei Zhang ◽  
Yansheng Wang ◽  
Jun Fan
Keyword(s):  
Magnetic Field ◽  
Near Field ◽  
Field Measurements ◽  
Probe Design

Investigation of chemical composition of meat using spatially off-set Raman spectroscopy

The Analyst ◽  
2019 ◽  
Vol 144 (8) ◽  
pp. 2618-2627 ◽  
Author(s):  
Saeideh Ostovar pour ◽  
Stephanie M. Fowler ◽  
David L. Hopkins ◽  
Peter J. Torley ◽  
Harsharn Gill ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Chemical Composition ◽  
Biological Tissues ◽  
Non Invasive

Spatially off-set Raman spectroscopy (SORS) offers non-invasive chemical characterisation of the sub-surface of various biological tissues as it permits the assessment of diffusely scattering samples at depths of several orders of magnitude deeper than conventional Raman spectroscopy.

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