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Throughout history a variety of therapeutic tools have been studied as possible enhancers of sports activities. This study proposes the use of Capacitive-Resistive Electric Transfer (CRET) as a performance booster to paralympic athletes, specifically those belonging to the Spanish Paralympic swimming committee. The study was a randomized, single-blind, and observer-blind, crossover clinical trial. Six athletes were randomly assigned to three groups: one treated with CRET (A); a placebo group (B) and a control group (C). The CRET group attended a twenty-minute session before being subjected to pool trials at distances of 50 and 100 m at maximum performance. Measurements were in two dimensions: time in seconds and the Borg scale for perceived exertion. Comparisons between groups were made with respect to distance and the main variables. In the case of perceived exertion, no significant changes were observed in any of the distances; however, in the case of the time variable, a significant difference was observed between Group A vs. Personal Record at 100 m distance (76.3 ± 6.8 vs. 68.4 ± 3.3). The proposed protocol and level of hyperthermia applied suggest refusal of CRET use for the 100-m distance a few minutes before sports practice. Our analysis suggests the need to modify the presented protocol. ClinicalTrials.gov identifier under NCT number: NCT04336007, Sección Deptal. de Radiología, Rehabilitación y Fisioterapia (Enfermería), Fac. de Enfermería, Fisioterapia y Podología, TRUE, pub

A small slot antenna has desirable characteristics for radio communications and location of an internal transceiver in-vivo medical applications. The effect of coupling between two identical antennas on the human torso was measured between 2.1 GHz antennas on the skin surface. The effect of an external field was measured as a function of the angle in the horizontal plane to quantify noise isolation. The perimeter separation loss was approximately 0.25 dB/mm. The external radio source induces currents in the soft conducting tissue resulting in a sinc radiation pattern for the antenna/body combination with a front-to-back ratio of approximately 12 dB. As the UHF band is commonly used in many non-medical applications, there is concern that external radio sources can result in a reduced signal to noise ratio and perturbed field strength measurements on the skin.

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Eng & Built Env, Science, Environment, Engineering and Technology, Measurements of electromagnetic fields are used for a wide range of applications. Often such measurements provide a non-destructive and non-intrusive way of obtaining information about the internal structure and other properties of the medium. Observations may be conducted across a very broad frequency range. Depending on the application domain, the frequency bands may range from the UHF band in biomedical engineering to the ULF band in geophysics. This thesis reports on several experiments where the electric and magnetic fields were measured on the surface of different media for the purpose of determining the electric properties of the material (electric conductivity and relative permittivity). A series of interference nulls were observed while measuring the electric field at UHF frequencies on the surface of a large, uniform sand dune. The source of the field was a transmitter buried in sand. The same pattern was observed after substituting the active transmitter with a passive scatterer exposed to a surface located electromagnetic transmitter. The scatterer then became a source of the electromagnetic field producing the interference pattern identical to the pattern observed in case of the active transmitter. Modelling of the surface electric field was done using known closed-form solutions for a uniform halfspace and by using an FDTD EM solver. Both approaches showed a close match with the measured fields. By varying the resistivity and the electric permittivity in the constructed models, it is demonstrated that the observed pattern (position of the nulls, nulls depth) depend on these electric properties. The inverse problem is posed with the goal of determining the electric properties of the material using the observed field. The inverse problem was solved, and the conductivity and relative permittivity of sand were determined. Two experiments conducted in different conditions showed the following results: conductivity 1×10-6 S/m and relative permittivity of 2.1