Take-Home Messages

• Microwave techniques may provide a convenient method of noninvasive hydration assessment due to the strong relationship between dielectric properties and water content in biological tissues.
• The feasibility of microwave hydration assessment is demonstrated through a physiologically-driven framework for modeling changes in microwave properties at the extremities during dehydration.
• Our target application is hydration assessment in athletes and older adults due to the elevated risk of dehydration from their activity, environment, and/or physiological changes.
• It is found that permittivity is a more sensitive metric than conductivity when assessing water-loss dehydration.
• The modeling techniques developed in this paper provide the framework for interpreting in vivo experimental measurements in the context of hydration assessment.

Take-Home Messages

• This paper provides a detailed survey related to the possible health hazards linked with EMF exposure based on what empirical studies suggest and the different metrics that are currently used for evaluating, limiting and mitigating the effects of this type of exposure on the general public.
• Brain tumour is still the main cause of concerns, which may be related to the extensive use of wireless devices, even though the effects of EMF exposure is now being investigated in other parts of the body (e.g. eyes, reproductive system). Moreover, some studies advocate a modification of the guidelines to better take into account the duration of exposure (i.e. long-term exposure).
• Generic/composite metrics (based on existing metrics) have recently been designed to better evaluate the exposure of large geographical area. A generic metric for measuring the individual exposure would also be of interest.
• Key 5G enabling technologies, such as densification, massive MIMO, and mmWave, will surely have an impact on the ambient level of EMF exposure in the near future, but they will also provide new opportunities to reduce it, e.g. context-aware beamforming or low exposure spatial modulation schemes.

Take-Home Messages

• Live cells were characterized individually in a fast, compact and label-free manner, and the dynamic range of the impedance spectroscopy was greatly increased by 2-port instead of 1-port measurements.
• A lumped equivalent circuit of nondispersive resistances and capacitances was found sufficient to explain the impedance spectrum of a cell between 9 kHz to 9 GHz, and the sensitivity of the cell impedance to microwave scattering (S) parameters was analyzed for the first time.
• The equivalent circuit parameters were found the most sensitive to the insertion loss of a series-trapped cell and the return loss of a shunt-trapped cell on the coplanar waveguide.
• The equivalent circuit parameters could be reliably extracted because low-frequency S-parameters were mainly governed by the membrane resistance, high-frequency S-parameters were mainly governed by the cytoplasm capacitance, and intermediate-frequency S-parameters were mainly governed by the membrane capacitance and cytoplasm resistance.
• The theory of ultrawideband impedance spectroscopy was carefully derived and documented for the first time.

Take-Home Messages

• Brain strokes are one of the leading causes of disability and mortality in adults in developed countries. We investigate how microwave tomography reveals changes in the brain’ tissues and thereby enable to detect and identify the type of stroke.
• We demonstrate that hemorrhagic stroke can be automatically identified with microwave tomography.
• Because of portability and cost effectiveness, microwave imaging systems may significantly improve the medical care of cerebrovascular accidents.
• Stroke identification including images reconstruction and automatic detection lasts less than 5 minutes.
• We implement massive parallel computing to solve the electromagnetic inverse problem and to speed up the reconstruction process.

Take-Home Messages

• We exploit a low-cost and inkjet printed UHF RFID tag as a sensor by modifying the equivalent circuit of the antenna to mitigate the effects of water, blood, and the human body.
• The targeted biological and medical applications are intravenous (IV) level sensing, blood storage management, and wound healing detection.
• The proposed RFID tag antenna features impedance match with Impinj R6 RFID from 890 MHz – 937 MHz and has a read range of 3 m, 2.5 m and 1.5 m on the surface of a water bottle, IV solution and blood bag, respectively.
• As compared with traditional designs, this tag antenna provides 26 % more read range with relatively small size 40  14 mm2 and has a specialty of water proximity sensing, leading to a compact and low-cost solution which is ideal for mass production.
• These features make this tag ideal for healthcare application in hospitals, which can add better facilitation for patient monitoring and also reduces the cost.

Take-Home Messages

• This proposed protocol evaluates the ability of a microwave imaging system to provide sufficient data quality.
• The protocol enables the identification of the system-specific resolution, which in practice is worse than the theoretical estimate.
• The approach is applicable to various biomedical microwave-imaging applications through modifications of the measured phantoms.
• The approach helps identify faults in the imaging setup and is suggestive of hardware modifications that remedy these faults.
• The flexibility of the protocol enables its application (with minor modifications) to any acquisition surface (e.g. planar, cylindrical, hemispherical antenna orientation).