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2. Application of the Monte Carlo Method for the Estimation of Uncertainty in Radiofrequency Field Spot Measurements

Author

Iakovidis S., Apostolidis C., and Samaras T.

Subjects
uncertainty, monte carlo, exposure quotient, electromagnetic field measurements, human exposure, Mathematics, QA1-939
Abstract

The objective of the present work is the application of the Monte Carlo method (GUMS1) for evaluating uncertainty in electromagnetic field measurements and the comparison of the results with the ones obtained using the 'standard' method (GUM). In particular, the two methods are applied in order to evaluate the field measurement uncertainty using a frequency selective radiation meter and the Total Exposure Quotient (TEQ) uncertainty. Comparative results are presented in order to highlight cases where GUMS1 results deviate significantly from the ones obtained using GUM, such as the presence of a non-linear mathematical model connecting the inputs with the output quantity (case of the TEQ model) or the presence of a dominant nonnormal distribution of an input quantity (case of U-shaped mismatch uncertainty). The deviation of the results obtained from the two methods can even lead to different decisions regarding the conformance with the exposure reference levels.

Published
2015
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8. Estimating the effective anisotropy of ferromagnetic nanoparticles through magnetic and calorimetric simulations.

Author

Maniotis, N., Nazlidis, A., Myrovali, E., Makridis, A., Angelakeris, M., and Samaras, T.

Subjects
ANISOTROPY, FERROMAGNETIC materials, MAGNETIC nanoparticles, HYSTERESIS loop, FINITE element method
Abstract

Magnetic nanoparticle-mediated hyperthermia holds great promise as a treatment for cancer. The key measure used for characterizing the heating efficiency of nanoparticles in this context is the specific loss power, which may be derived from the magnetic hysteresis loop area. An intrinsic property of magnetic nanoparticles that influences specific loss power is magnetic anisotropy, which is difficult to estimate because of its complicated nature. This work presents a simple method for the theoretical estimation of magnetic anisotropy in ferromagnetic magnetite nanoparticles of 40 nm diameter. We conduct numerical calculations of hysteresis loops, employing a Monte Carlo technique for a typical anisotropy range of 2 to 11 kJ/m3. To assess the validity of our simulations and to estimate the optimum anisotropy for our magnetic nanoparticles, we compare numerically estimated loops with an experimental one. Using the finite element method, we perform heat transfer simulations to calculate temporal temperature distributions in an aqueous dispersion of magnetic nanoparticles for a fixed range of anisotropy values. Simulated heating curves are compared with experimental ones to verify magnetic nanoparticle anisotropy, which coincides with the one obtained from the above Monte Carlo simulations and is equal to 9 kJ/m3. Therefore, in this study, we propose a rigorous quantification of the anisotropy of ferromagnetic nanoparticles both magnetically and calorimetrically through hysteresis loop estimation and heat transfer simulations, respectively, so that their specific loss power can be accurately determined and used for treatment planning in clinical practice. [ABSTRACT FROM AUTHOR]

Published
2019
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11. Magnetic nanoparticles: An indicator of health risks related to anthropogenic airborne particulate matter

Author

European Commission, Kermenidou, M., Balcells, Lluis, Martínez Boubeta, Carlos, Chatziavramidis, A., Konstantinidis, I., Samaras, T., Sarigiannis, D., Simeonidis, Konstantinos, European Commission, Kermenidou, M., Balcells, Lluis, Martínez Boubeta, Carlos, Chatziavramidis, A., Konstantinidis, I., Samaras, T., Sarigiannis, D., and Simeonidis, Konstantinos

Abstract

Due to their small dimensions, airborne particles are able to penetrate through inhalation into many human organs, from the lungs to the cardiovascular system and the brain, which can threaten our health. This work establishes a novel approach of collecting quantitative data regarding the fraction, the composition and the size distribution of combustion-emitted particulate matter through the magnetic characterization and analysis of samples received by common air pollution monitoring. To this end, SQUID magnetometry measurements were carried out for samples from urban and suburban areas in Thessaloniki, the second largest city of Greece, taking into consideration the seasonal and weekly variation of airborne particles levels as determined by occurring traffic and meteorological conditions. The level of estimated magnetically-responding atmospheric particulate matter was at least 0.5 % wt. of the collected samples, mostly being present in the form of ultrafine particles with nuclei sizes of approximately 14 nm and their aggregates. The estimated quantities of magnetic particulate matter show maximum values during autumn months (0.8 % wt.) when increased commuting takes place, appearing higher in the city center by up to 50% than those in suburban areas. In combination with high-resolution transmission electron imaging and elemental analysis, it was found that Fe3O4 and similar ferrites, some of them attached to heavy metals (Co, Cr), are the dominant magnetic contributors arising from anthropogenic high-temperature processes, e.g. due to traffic emissions. Importantly, nasal cytologic samples collected from residents of both central and suburban areas showed same pattern in what concerns magnetic behavior, thus verifying the critical role of nanosized magnetic particles in the assessment of air pollution threats. Despite the inherent statistical limitations of our study, such findings also indicate the potential transmission of infectious pathogens by means of pollut

Published
2021

12. Guidelines on the benefit-risk assessment of the presence of phthalates in certain medical devices covering phthalates which are carcinogenic, mutagenic, toxic to reproduction (CMR) or have endocrine-disrupting (ED) properties

Author

De Jong, W.H., Borges, T., Ion, R.M., Panagiotakos, D., Testai, E., Vermeire, T., Bernauer, U., Rousselle, C., Bégué, Sté, Kopperud, H.M., Milana, M.R., Schmidt, T., Pignatti, F., Stoyanova, E., Volk, K., Bertollini, R., De Voogt, P., Duarte-Davidson, R., Hoet, P., Kraetke, R., Proykova, A., Samaras, T., Scott, M., Slama, R., Vighi, M., and Zacharo, S.

Published
2020
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13. Meteorological Aspects of Two Modes of Lightning Triggered Upward Lightning (LTUL) Events in Sprite-Producing MCSs

Author

Lyons, W. A, Nelson, T. E, Warner, T. A, Lang, T. J, Cummins, K, Quick, M, Rison, W, Krehbiel, P, Cummer, S. A, Meyers, J, Samaras, T, Samaras, P, and Young, C

Subjects
Meteorology And Climatology
Abstract

During the 2013 convective storm season, a high resolution 3-D Lightning Mapping Array was deployed to north central Kansas (Cummins et al, this conference.) In conjunction with fixed and mobile camera systems and electric field mills, this allowed for detailed investigations of lightning induced upward lighting (LTUL) discharges from tall objects in the region, including wind turbines. Also, concurrent observations using a network of low-light cameras deployed over the central U.S. as part of the PhOCAL program detected transient luminous events (TLEs) above the Kansas LMA (KSLMA). During the night of 29-30 May 2013, waves of precipitation associated with several large MCSs traversing Kansas moved through the KSLMA domain. We focus on two LTUL events that exemplify two modes of upward lightning production from tall structures. At 0859Z, 30 May 2013, a nearby + 92 kA CG, with extensive in-cloud branching passing overhead a wind farm, was followed by complex LTUL discharges from four turbines. In addition, a sprite was confirmed by the Bennett, CO SpriteNet camera. The parent flash covered a very large area. It initiated near the MCS convective leading line ~150 km to the south, and traveled into a stratiform precipitation maximum over the KSLMA. Typically when a +CG precedes an LTUL, the triggering component is either 1) the return stroke that traverses the leader network which initially forms near the towers or 2) new negative leader activity that develops once the return stroke reaches the end of the initial leader network that may not have initially been near the tower. In the latter case, the new leader development passes near the towers and triggers upward positive leaders similar to those associated with only an intracloud flash. The +CG return stroke may hit >10 km from the towers and the new leader development may travel extensive distances before getting close enough to the towers to trigger upward lightning. In this case, there was the typical long delay between the +CG return stroke and LTUL initiation (10s to 100s of ms). The parent lightning discharges for both sprites and LTULs have many common aspects and tend to occur in similar meteorological regimes, with the two phenomena often occurring together. An earlier LUTL, at 2320Z, 29 May 2013 was captured at 9900 fps by a Phantom camera in the PhOCAL mobile Lightning Investigation Vehicle (LIV). This discharge, exhibiting numerous recoil leaders, also occurred in a stratiform region some ~50-100 km north of an MCS convective core. While there was no preceding +CG, there was an extensive network of IC channels, one of which passed overhead close to the turbine. These observations are consistent with the ongoing UPLIGHTS studies of LTULs from tall towers in Rapid City. While a +CG is usually involved (~85% of the time), the LTUL occurs because of the associated extensive in cloud components passing over towers. The earlier case without a +CG typifies this second mode where the triggering component is a negative leader associated with the IC activity passing near the towers initiates the upward positive leaders. We will discuss the parent discharges, shown in their meteorological (radar and satellite) context, and attempt to better understand the charge structures present in both the convective and stratiform regions of the MCS. The sprite and its relationship to the parent discharge will similarly be discussed

Published
2014

18. Advancing Rational Exploitation of Water Irrigation Using 5G-IoT Capabilities: The AREThOU5A Project

Author

Boursianis, A. D., primary, Papadopoulou, M. S., additional, Damantoulakis, P., additional, Karampatea, A., additional, Doanis, P., additional, Geourgoulas, D., additional, Skoufa, A., additional, Valavanis, D., additional, Apostolidis, C., additional, Babas, D. G., additional, Baltzis, K. B., additional, Kaifas, T. N., additional, Siozios, K., additional, Siskos, S., additional, Samaras, T., additional, Siakavara, K., additional, Nikolaidis, S., additional, Goudos, S. K., additional, Liopa-Tsakalidi, A., additional, Barouchas, P., additional, Kasimis, I., additional, Kalamaras, G., additional, Merkouris, D., additional, Perrakis, G., additional, Tsirogiannis, C., additional, Gotsis, A., additional, and Maliatsos, K., additional

Published
2019
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21. Europe and the future for WPT COST action IC1301 team

Author

Carvalho,NB, Georgiadis,A, Costanzo,A, Stevens,N, Kracek,J, Luís Manuel Pessoa, Roselli,L, Dualibe,F, Schreurs,D, Mutlu,S, Rogier,H, Visser,H, Takacs,A, Rocca,P, Dimitriou,A, Michalski,J, Raida,Z, Tedjini,S, Joseph,W, Duroc,Y, Sahalos,JN, Bletsas,A, Samaras,T, Nikoletseas,S, Raptis,TP, Boaventura,A, Collado,A, Trevisan,R, Minnaert,B, Svanda,M, Pereira,M, Mongiardo,M, Popov,G, Pan,N, Aubert,H, Viani,F, Siachalou,S, Kant,P, Vera,GA, Polycarpou,AC, Cruz,P, Mastri,F, Mazanek,M, Santos,H, Alimenti,F, Garcia Vazquez,H, Pollin,S, Poli,L, Belo,D, Masotti,D, Machac,J, Vítor Grade Tavares, Mezzanotte,P, Ndungidi,P, Oliveri,G, Fernandes,R, Salgado,H, Moeyaert,V, Massa,A, Goncalves,R, Pinho,P, Monti,G, Tarricone,L, Dionigi,M, Russer,P, and Russer,J

Subjects
IBCN
Published
2017

22. The Law of Entropy and the Aging Process

Author

Samaras, T. T.

Abstract

Entrophy, internal work on body, mass, and energy are analyzed in relation to the human system and its rate of deterioration. Progressive development, increasing physical and mental efficiency, low caloric intake, and configuration management techniques are recommended for combating the aging process. (Author/SDH)

Published
1974

26. Electromagnetic field exposure assessment in Europe radiofrequency fields (10 MHz–6 GHz)

Author

Gajsek, Ravazzani P., Wiart J., Grellier J., Samaras T., Thuróczy G., Radio-Fréquences Microondes et Ondes Millimétriques (RFM2), Laboratoire Traitement et Communication de l'Information (LTCI), Institut Mines-Télécom [Paris] (IMT)-Télécom Paris-Institut Mines-Télécom [Paris] (IMT)-Télécom Paris, Département Communications & Electronique (COMELEC), and Télécom ParisTech

Subjects
Electromagnetic field, exposure assessment, sources of exposure, Epidemiology, Rf exposure, Future risk, Population, exposimetry, Toxicology, Emf exposure, [SPI]Engineering Sciences [physics], Electromagnetic Fields, RF electromagnetic fields, Radiation Monitoring, Humans, education, Remote sensing, Exposure assessment, education.field_of_study, business.industry, Public Health, Environmental and Occupational Health, Electrical engineering, European population, Radiation Exposure, Pollution, [STAT]Statistics [stat], Europe, Radiation monitoring, Environmental science, business
Abstract

Average levels of exposure to radiofrequency (RF) electromagnetic fields (EMFs) of the general public in Europe are difficult to summarize, as exposure levels have been reported differently in those studies in which they have been measured, and a large proportion of reported measurements were very low, sometimes falling below detection limits of the equipment used. The goal of this paper is to present an overview of the scientific literature on RF EMF exposure in Europe and to characterize exposure within the European population. A comparative analysis of the results of spot or long-term RF EMF measurements in the EU indicated that mean electric field strengths were between 0.08 V/m and 1.8 V/m. The overwhelming majority of measured mean electric field strengths were

Published
2013
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27. Effectiveness of FDTD in Predicting SAR Distributions from the Lucite Cone Applicator

Author

Samaras, T., Rietveld, P. J. M., and van Rhoon, G. C.

Subjects
Breast cancer -- Care and treatment, Microwaves -- Research, Hyperthermia treatment systems (Medical care) -- Research, Thermotherapy -- Equipment and supplies, Business, Computers, Electronics, Electronics and electrical industries
Abstract

The benefits of using superficial hyperthermia together with radiotherapy has long been proven for recurrent breast carcinomas. The lucite cone applicator has been introduced by some hospital hyperthermia units for superficial treatments. It is characterized by a large effective field size. The modeling techniques used in the past for the study of this, as well as other applicators used for superficial hyperthermia, have failed to address some treatment parameters, such as the dimensions of the waterbolus, which are significant for clinical practice. In this paper, the finite-difference time-domain (FDTD) method is used for modeling the applicators. The numerical results are compared with thermographic measurements. The agreement between predicted and measured specific-absorption-rate distribution is very good. The use of the FDTD method is expected to promote the study of treatment specific factors and help improve future treatment quality. Index Terms--cancer, dielectric loaded waveguides, electro-magnetic heating, FDTD, hyperthermia, medical treatment.

Published
2000

28. Arrangement at the nanoscale: Effect on magnetic particle hyperthermia

Author

Myrovali, E., primary, Maniotis, N., additional, Makridis, A., additional, Terzopoulou, A., additional, Ntomprougkidis, V., additional, Simeonidis, K., additional, Sakellari, D., additional, Kalogirou, O., additional, Samaras, T., additional, Salikhov, R., additional, Spasova, M., additional, Farle, M., additional, Wiedwald, U., additional, and Angelakeris, M., additional

Published
2016
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31. EFHRAN project : exposure assessment to radiofrequency EMF in Europe

Author

Thuróczy, György, Bakos, Jozsef, Kubinyi, G., Gajsek, Peter, Samaras, T., Wiart, Joe, Ravazzani, P., Institut National de l'Environnement Industriel et des Risques (INERIS), Department of Non-ionising Radiation, National Research Institute for Radiobiology and Radiohygiene, Institute of Non-ionizing Radiation, Laboratory of Heat Transfer and Environmental Engineering [Thessaloniki] (LHTEE), Aristotle University of Thessaloniki, Orange Labs [Issy les Moulineaux], France Télécom, and Civs, Gestionnaire

Subjects
[SDV.TOX] Life Sciences [q-bio]/Toxicology, [SDE] Environmental Sciences, [SDV.TOX]Life Sciences [q-bio]/Toxicology, [SDE]Environmental Sciences
Published
2012

32. Fetus temperature increase estimation due to RFID exposure

Author

Fiocchi S, Markakis IA, Parazzini M, Liorni I, Ravazzani P, and Samaras T.

Abstract

This study aims to estimate the temperature increase in fetal tissues due to RFID (Radio Frequency IDentification) devices exposure. A mathematical model of fetal to maternal heat exchange, including external heat load due to the RF exposure, was developed on the basis of a multicompartment approach previously described in the literature. The results showed the efficiency of the heat transport system in limiting the temperature increase due to the exposure to 0.02 °C even after 1 hour of exposure.

Published
2012

33. Compartmental model for the estimation of temperature increase in fetus due to RFID exposure

Author

Fiocchi S, Markakis IA, Parazzini M, Liorni I, Ravazzani P, and Samaras T.

Abstract

This paper describes a mathematical model of foetal to maternal heat exchange based on a multi-compartment approach previously described in the literature, modified to include the external heat load due to the RF exposure. Then, it is applied to evaluate the temperature increase due to a RFID system exposure.

Published
2012

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