Maria Christopoulou

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The peak spatial specific absorption rate (SAR) assessed with the standardized specific anthropometric mannequin head phantom has been shown to yield a conservative exposure estimate for both adults and children using mobile phones. There are, however, questions remaining concerning the impact of age-dependent dielectric tissue properties and age-dependent(More)
In this study, we present a novel, miniaturized, biocompatible antenna at the medical implant communications service (MICS) band (402–405 MHz) for integration in wireless biotelemetry devices implanted in the human head. To reduce simulation time, the antenna is designed while in the center of a skin tissue simulating box and subsequently implanted(More)
Optimal normal bases are special cases of the so-called Gauss periods (Disquisitiones Arithmeticae, Articles 343-366); in particular, optimal normal bases are Gauss periods of type (n,1) for any characteristic and type (n,2) for characteristic 2. We present the multiplication tables and complexities of Gauss periods of type (n, t) for all n and t = 3,4,5(More)
A novel exposure system for double-blind human electromagnetic provocation studies has been developed that satisfies the precision, control of fields and potential artifacts, and provides the flexibility to investigate the response of hypotheses-driven electromagnetic field exposure schemes on brain function, ranging from extremely low frequency (ELF) to(More)
A broadband, circular, double-stacked, implantable planar inverted-F antenna (PIFA) is proposed for biomedical telemetry at f0= 402 MHz. Both patches are meandered and a high permittivity substrate material is used to limit the radius and height of the antenna to 3.6 mm and 0.7 mm, respectively. The tuning and radiation characteristics as well as the(More)
Let Fq be a finite field and consider an extension Fqn where an optimal normal element exists. Using the trace of an optimal normal element in Fqn , we provide low complexity normal elements in Fqm , with m = n/k. We give theorems for Type I and Type II optimal normal elements. When Type I normal elements are used with m = n/2, m odd and q even, our(More)
Due to the greatly non-uniform field distribution induced in brain tissues by radio frequency electromagnetic sources, the exposure of anatomical and functional regions of the brain may be a key issue in interpreting laboratory findings and epidemiological studies concerning endpoints related to the central nervous system. This paper introduces the(More)
Microwave radiometry is a passive technique used to measure in-depth temperature distributions inside the human body, potentially useful in clinical applications. Experimental data imply that it may provide the capability of detecting in-depth local variations of temperature and/or conductivity of excitable tissues at microwave frequencies. Specifically,(More)
The scope of this paper is to comparatively present the extremely low-frequency (ELF) measurements performed at four power plants in Greece, focusing on: (a) the worst-case exposure conditions, (b) the existence of magnetic field harmonic components, (c) the technical similarities among the power plants and (d) comparison of the measured percentages of(More)
BACKGROUND Autologous blood transfusion presents few infectious or immunologic side effects. The aim of the present study was to determine the impact of autologous blood transfusion with or without recombinant human erythropoietin (rHuEPO) in patients who underwent elective maxillofacial operations. MATERIAL Seventy eight consecutive patients (29 men and(More)