Made available in DSpace on 2014-10-09T12:38:21Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:07Z (GMT). No. of bitstreams: 1 05678.pdf: 6012797 bytes, checksum: fe9d7fe0fee771d558f91a7bffb7cfa3 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-04-27T15:54:57Z No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:50:45Z (GMT) No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) / Made available in DSpace on 2017-05-12T15:50:46Z (GMT). No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) Previous issue date: 2014-08-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O sistema de telecomunicação móvel tem crescido ao longo dos anos. A comunidade científica tem demonstrado uma crescente preocupação sobre os possíveis efeitos da exposição à radiação electromagnética de radiofrequência (RFEMR) emitida por dispositivos móveis sobre a saúde dos usuários. Este estudo teve como objetivo avaliar os efeitos da RF-EMR sobre a via de MAPKs, verificando os níveis de fosforilação das enzimas MEK 1 / 2 e ERK 1 / 2, em células do hipotálamo e hipófise, sobre a secreção de catecolaminas, nível de glicose sérica, consolidação da memória de longo prazo e estabelecimento de comportamento de ansiedade. Ratos Wistar machos, com 60 dias de idade, foram expostos à radiação emitida pelos telefones celulares (1,8 GHz) em condições agudas (1 e 3 horas de exposição) e crônicas (3 e 10 noites de exposição). Os níveis de fosforilação de MEK 1 / 2 e ERK 1 / 2 foram alterados em células hipotalâmicas de animais expostos por 1 hora. Após 3 horas, 3 noites e 10 noites, foi observada alteração somente no nível de fosforilação das enzimas MEK 1 / 2, em células hipotalâmicas; e nenhuma alteração foi constatada na fosforilação das enzimas MEK 1 / 2 e ERK 1 / 2, em células hipofisárias. As exposições por períodos agudos promoveram aumento da secreção basal de catecolaminas e a glicemia foi alterada após 1 hora e 10 noites. Não foi constatado comportamento estado de ansiedade pelo teste de cruz elevada em quaisquer períodos de exposição. Porém, a exposição crônica, por 10 noites, aumentou a secreção de catecolamina, estimulada por cafeína, concomitantemente à diminuição a glicemia, podendo afetar a consolidação da memória. Os resultados sugerem que a exposição de ratos a campos electromagnéticos emitidos por celulares é capaz de alterar a via de MAPKs, mudar o perfil de secreção basal e estimulada de catecolaminas, de glicemia, além de afetar a consolidação de memória de longo prazo. / The mobile telecommunication system has grown over the years. There has been a growing concern about the possible effects of exposure to radiofrequency electromagnetic radiation (RF-EMR) emitted by mobile devices on the health of users. This study aimed to evaluate the effects of whole-body RF-EMR exposure on MAPK's pathway, verifying the phosphorylation levels of MEK 1 / 2 and ERK 1 / 2, in hypothalamus and pituitary cells, catecholamine secretion, serum glucose, long-term memory consolidation and anxiety-like behavior occurrence. Male Wistar rats, 60 days old, were subjected to electromagnetic waves emitted by mobile phones (1.8 GHz) in acute (1 and 3 hours of exposure) and chronic (3 and 10 nights of exposure) conditions. The phosphorylation levels of MEK 1 / 2 and ERK 1 / 2 changed in hypothalamus cells after 1 hour of exposure. After 3 hours, 3 nights and 10 nights, we have found changes only in phosphorylation of MEK 1 / 2 (hypothalamus); no changes were found in MEK 1 / 2 and ERK 1 / 2 from pituitary cells. The acute exposures lead to the increase of basal catecholamine secretion and the glycemia changed after 1 hour and 10 nights. On the other hand, the chronic exposure increased the catecholamine release, by caffeine stimulation, but decreased the serum glucose level, disturbing the memory consolidation. The results suggest that exposure of rats to electromagnetic fields emitted by mobile phones is able to change the MAPK's pathway, profile of basal and stimulated secretion of catecholamines, and serum glucose level besides affecting long-term memory.

This diploma thesis deals with electromagnetic radiation in its frequency spectrum. It also divides radiation into ionizing and non-ionizing. The principle of its effects and possible health problems from radiation exposure are also described. Hygienic limits – the maximum allowable and reference values of non-ionizing radiation are analysed too. The thesis should prove that the things of everyday need do not threaten the lives of human beings and are in compliance with the regulation No. 1/2008 Sb. on Health Protection Against Non-Ionizing Radiation. Measurement of low-frequency part is carried out with the cooperation of The National Institute of Public Health. Measurement of high-frequency part was carried out in 3 flats. The aim of this measurement was to find out the change of power density with the moving in a flat and the influence of the barriers (in this case walls).

<p>With the development of wireless communication technology, second-, third-, fourth-generation transmission systems based on electromagnetic (EM) waves are widely used. At the same time, public concerns have been raised about whether the use of such systems will have an impact on health and safety standards. The heating effect is the most prominent and scientifically verifiable biological effect. So, the influence of EM waves on human body is addressed by studying the heating characteristics on head models.</p> <p>The objective of this thesis is to study the effects of radio frequency (RF) waves radiation from mobile phones on the human head under different transmission generations. The six-layer head model is used to evaluate the specific absorption rate (SAR) distribution and thermal effect. This model allows to study the effects of SAR and temperature rise without the need for high computational resources. In order to find the effect of temperature rise and exposure time, the finite difference time domain (FDTD) method was used to solve the biothermal equation with appropriate boundary conditions.</p> <p>Also, different age-dependent head models are used to study the differences of SAR for children at different ages.</p> <p>In general, the results show that with the increase in frequency, the influence of the EM wave is more pronounced, as demonstrated by the SAR and temperature rise distribution. In addition, SAR distribution of younger ages show a significant increase, which indicates that children exposed to EM waves are subject to more harmed. </p>

Indiana University School of Dentistry / Introduction: The goal of nonsurgical root canal therapy is to reduce the bacterial load within an infected root canal system, and the subsequent objective is to prevent or treat apical periodontitis. Clinical studies have shown more expedient healing of apical periodontitis treated with electromagnetic wave stimulation (EMS) as compared to apical periodontitis not treated with EMS. Stimulation of osteoblasts and growth factors has been shown when EMS was applied to rat calvaria, resulting in increased bone healing. Objective: The purpose of this vitro study was to evaluate the effects of EMS on the proliferation and differentiation of osteoblasts. Using primary neonatal calvaria osteoblast-lineage cells, the effects of different EMS regimens on proliferation, alkaline phosphatase (ALP) activity, and mineral deposition were determined. Materials and Methods: EMS regimen included currents of 0mA, 0.1mA, 1mA, and 10mA delivered for five consecutive 1s pulses per day for one, two, and three days. Cell proliferation was assayed after 1 or 2 days using an MTS assay. Alkaline phosphatase activity and mineral deposition were assayed after culturing the cells in osteogenic media containing ascorbic acid and -glycerol phosphate for 7 days. Comparisons were performed using analysis of variance, with a 5% significance level. Results: There was no statistically significant differences noted in MTS proliferation and mineral deposition between the experiment EMS treatment groups of 0.1, 1.0, and 10.0 mA compared to the control group of 0 mA current on calvaria-derived osteoblast. While there were no statistically significant differences noted in ALP activity in the 0.1, and 1.0 mA EMS groups, compared to 0 mA control, alkaline phosphatase activity was significantly increased in the 10 mA EMS group. Conclusion: There was no significant differences in MTS proliferation and mineral deposition of the EMS group compared to the control group. However, 10 mA EMS favored increased ALP activity suggesting EMS can promote matrix maturation by osteoblasts. Additional in vitro experimental studies, including different stem cell populations, culture duration and EMS treatment regimens are needed to understand the mechanism of action of EMS for future applications in regenerative endodontics.

Thesis (MSc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The selective excitation of an arbitrary vibrational level of a polyatomic molecule, without passage through an intermediary electronic excited state is demonstrated. This was achieved by simulating the interaction of a shaped, femtosecond pulse with one vibrational mode of the molecule. The carrier frequency of the pulse is chosen near resonant to the ground-to- rst-excited vibrational transition of the mode, and the pulse shape is optimized via closed-loop feedback. The simulation concentrates on the rst few vibrationally excited states since the density of states is still low, thus ensuring that the inter-vibrational decoherence time is relatively long compared to the pulse length. While various molecules were investigated this study focuses onUF6 for which detailed spectroscopic data for the v3 vibrational mode is available in literature. A multilevel model was developed and can be adapted for any number of levels. The model reported here was limited to a vibrational quantum number of four. The spectroscopic data included anharmonic splitting as well as forbidden transitions. The effect of rotational levels was not included. A density matrix approach was followed because this will allow for the introduction of dephasing of the coherent excitation via thermalizing collisions with the reservoir, as well as inter-vibrational relaxation. The time evolution of the density matrix is given by the Von Neumann equations. / AFRIKAANSE OPSOMMING: Die selektiewe opwekking van 'n arbitrêre vibrasionele vlak van 'n poliatomies molekule sonder oorgang na 'n intermediëre elektroniese opgewekte toetstand word gedemonstreer. Dit was bereik deur die interaksie te simuleer van 'n gevormde, femtosekonde pulse met een vibrasionele mode van 'n molekule. Die draer frekwensie van die pulse is so gekies dat dit naby resonansie van die grond-tot-eerste-opgewekte vibrasionele oorgang van die mode is, die puls vorm word geoptimeer deur 'n geslote-lus terugvoer. Die simulasie konsentreer op die eerste paar vibrasionele opgewekte toestande, omdat die digtheid van toestande nog steeds laag is, dus verseker dit dat inter-vibrasionele de-koherensie tyd relatief lank is in vergelyking met die puls se lengte. Verskillende molekules was ondersoek vir die studie. Die fokus is op UF6 waarvoor gedetaileerde spektroskopiese data vir die v3 vibrasionele beskikbaar is in die literatuur. 'n Multivlak model was ontwikkel en kan aangepas word vir enige aantal van vlakke. Die model wat hier aangemeld is, is beperk tot die vibrasionele kwantum getal van vier. Die spektroskopiese data het anharmonies splitting so wel as nie toegelaatbare oorgange bevat. Die effek van rotasionele vlakke was nie in berekening geneem nie. 'n Digtheids matriks benadering was gevolg, omdat dit toelaat vir die dekoherensie. Die tyd evolusie van die digtheids matriks word gegee deur die Von Neumann vergelykings.

Coronal Mass Ejections (CMEs) and solar flares are energetic events taking place at the Sun that can affect the space weather or the near-Earth environment by the release of vast quantities of electromagnetic radiation and charged particles. Solar active regions are the areas where most flares and CMEs originate. Studying the associations among sunspot groups, flares, filaments, and CMEs is helpful in understanding the possible cause and effect relationships between these events and features. Forecasting space weather in a timely manner is important for protecting technological systems and human life on earth and in space. The research presented in this thesis introduces novel, fully computerised, machine learning-based decision rules and models that can be used within a system design for automated space weather forecasting. The system design in this work consists of three stages: (1) designing computer tools to find the associations among sunspot groups, flares, filaments, and CMEs (2) applying machine learning algorithms to the associations' datasets and (3) studying the evolution patterns of sunspot groups using time-series methods. Machine learning algorithms are used to provide computerised learning rules and models that enable the system to provide automated prediction of CMEs, flares, and evolution patterns of sunspot groups. These numerical rules are extracted from the characteristics, associations, and time-series analysis of the available historical solar data. The training of machine learning algorithms is based on data sets created by investigating the associations among sunspots, filaments, flares, and CMEs. Evolution patterns of sunspot areas and McIntosh classifications are analysed using a statistical machine learning method, namely the Hidden Markov Model (HMM).

Le travail de recherche proposé dans ce manuscrit consiste à modéliser le rayonnement électromagnétique de conducteurs filaires. En effet l’estimation du rayonnement est un enjeu majeur et l’utilisation de modèles exacts nous semble nécessaire. On propose donc dans ce mémoire une approche analytique qui permet de quantifier les niveaux de champs électromagnétiques rayonnés par les systèmes filaires. Dans un premier temps nous proposons un modèle analytique du calcul du champ électromagnétique rayonné par un système filaire basé sur un développement approfondi des équations de Maxwell. Ce formalisme est issu de la formulation intégrale du potentiel vecteur émis par une antenne filaire dont on supposera connu la distribution de courant. Le modèle analytique ainsi obtenu permet d’estimer aisément les champs sans avoir besoin de discrétiser ni le support de transmission ni l’espace d’observation. Pour enrichir notre modèle nous avons ensuite envisagé les cas où la distribution du courant le long des conducteurs était issu, soit de la théorie des lignes soit d’une simulation numérique basée sur la théorie des antennes, soit de mesures. Dans le cas où c’est la théorie des lignes qui est à la base de la détermination des courants distribués, nous proposons un formalisme analytique du champ électromagnétique rayonné basé uniquement sur la seule connaissance des courants et de leurs dérivées aux extrémités des conducteurs. Nous avons également montré que ce formalisme s’extrapole aisément au cas d’un réseau multifilaire. Dans le cas où la théorie des antennes ou des mesures sont à la base de la connaissance des courants distribués, on identifie ce courant par quelques pôles et résidus grâce à la méthode d’identification Matrix Pencil (MP). Le champ électromagnétique rayonné s’exprime alors par une série finie de termes intégrales. Ce formalisme reste analytique et présente l’avantage d’être adapté aux approches paramétriques et d’optimisations. Nos travaux de recherche ouvrent des perspectives de reconstruction de la distribution du courant par Matrix Pencil à partir de la connaissance du courant et de ses premières dérivées spatiales aux seules extrémités des conducteurs. Le champ électromagnétique rayonné sera alors déduit de notre modèle. / The research presented in this thesis is focused on the modelling of electromagnetic radiation from thin-wire configuration. The radiation assessment is one of the most important issues which strongly requires an accurate modelling. In this work, an analytic approach to evaluate electromagnetic field radiated from thin-wire structure sis proposed. In the first part, we propose an analytical model for calculation of the electromagnetic fields from wire structure derived from the Maxwell equations. This formalism arises from the integral formulation of the magnetic vector potential due to a known current distribution along a wire antenna. The analytical model enables one to readily calculate the fields without requirement of wire structure discretization or involving the propagation effect over the domain of interest. In order to improve the model, we subsequently analyze cases where the current distribution along the conductors is known, either obtained by using the transmission line theory, by numerical simulations based on the antenna theory, or by measurements. On the basis of the known current and its derivative at the ends of a two-wire configuration, obtained by using the transmission line theory, the proposed approach yields an analytical formalism for determination of the radiated electromagnetic field. This analytical formalism is readily extended to multiple wires structures, as well. Once the current distribution is determined by using the antenna theory, the proposed method extracts the corresponding poles and residues by using the Matrix Pencil Method (MPM). In this case, the radiated electromagnetic field is formulated just by few integral terms. The main advantage of the analytical formulation within the framework of the proposal approach is that the method is very suitable for parametric and optimisation studies. This research should be considered as an opener to the subject related to reconstruction of the current distribution by using the Matrix Pencil method (MPM) only based on the current and its first derivative at the wire structure ends. Consequently the radiated electromagnetic field may be subsequently readily calculated by using theproposed analytical model.

This thesis presents an efficient self-consistent Hybrid Spectral Ray Tracing (HSRT) technique for analysis and design of multi-scale sub-millimeter wave problems, where sub-wavelength features are modeled using rigorous methods, and complex structures with dimensions in the order of tens or even hundreds of wavelengths are modeled by asymptotic methods. Quasi-optical devices are used in imaging arrays for sub-millimeter and terahertz applications, THz time-domain spectroscopy (THz-TDS), high-speed wireless communications, and space applications to couple terahertz radiation from space to a hot electron bolometer. These devices and structures, as physically small they have become, are very large in terms of the wavelength of the driving quasi-optical sources and may have dimension in the tens or even hundreds of wavelengths. Simulation and design optimization of these devices and structures is an extremely challenging electromagnetic problem. The analysis of complex electrically large unbounded wave structures using rigorous methods such as method of moments (MoM), finite element method (FEM), and finite difference time domain (FDTD) method can become almost impossible due to the need for large computational resources. Asymptotic high-frequency techniques are used for analysis of electrically large quasi-optical systems and hybrid methods for solving multi-scale problems. Spectral Ray Tracing (SRT) has a number of unique advantages as a candidate for hybridization. The SRT method has the advantages of Spectral Theory of Diffraction (STD). STD can model reflection, refraction and diffraction of an arbitrary wave incident on the complex structure, which is not the case for diffraction theories such as Geometrical Theory of Diffraction (GTD), Uniform theory of Diffraction (UTD) and Uniform Asymptotic Theory (UAT). By including complex rays, SRT can effectively analyze both near-fields and far-fields accurately with minimal approximations. In this thesis, a novel matrix representation of SRT is presented that uses only one spectral integration per observation point and applied to modeling a hemispherical and hyper-hemispherical lens. The hybridization of SRT with commercially available FEM and MoM software is proposed in this work to solve the complexity of multi-scale analysis. This yields a computationally efficient self-consistent HSRT algorithm. Various arrangements of the Hybrid SRT method such as FEM-SRT, and MoM-SRT, are investigated and validated through comparison of radiation patterns with Ansoft HFSS for the FEM method, FEKO for MoM, Multi-level Fast Multipole Method (MLFMM) and physical optics. For that a bow-tie terahertz antenna backed by hyper-hemispherical silicon lens, an on-chip planar dipole fabricated in SiGe:C BiCMOS technology and attached to a hyper-hemispherical silicon lens and a double-slot antenna backed by silica lens will be used as sample structures to be analyzed using the HSRT. Computational performance (memory requirement, CPU/GPU time) of developed algorithm is compared to other methods in commercially available software. It is shown that the MoM-SRT, in its present implementation, is more accurate than MoM-PO but comparable in speed. However, as shown in this thesis, MoM-SRT can take advantage of parallel processing and GPU. The HSRT algorithm is applied to simulation of on-chip dipole antenna backed by Silicon lens and integrated with a 180-GHz VCO and radiation pattern compared with measurements. The radiation pattern is measured in a quasi-optical configuration using a power detector. In addition, it is shown that the matrix formulation of SRT and HSRT are promising approaches for solving complex electrically large problems with high accuracy. This thesis also expounds on new measurement setup specifically developed for measuring integrated antennas, radiation pattern and gain of the embedded on-chip antenna in the mmW/ terahertz range. In this method, the radiation pattern is first measured in a quasi-optical configuration using a power detector. Subsequently, the radiated power is estimated form the integration over the radiation pattern. Finally, the antenna gain is obtained from the measurement of a two-antenna system.

This thesis presents an efficient self-consistent Hybrid Spectral Ray Tracing (HSRT) technique for analysis and design of multi-scale sub-millimeter wave problems, where sub-wavelength features are modeled using rigorous methods, and complex structures with dimensions in the order of tens or even hundreds of wavelengths are modeled by asymptotic methods. Quasi-optical devices are used in imaging arrays for sub-millimeter and terahertz applications, THz time-domain spectroscopy (THz-TDS), high-speed wireless communications, and space applications to couple terahertz radiation from space to a hot electron bolometer. These devices and structures, as physically small they have become, are very large in terms of the wavelength of the driving quasi-optical sources and may have dimension in the tens or even hundreds of wavelengths. Simulation and design optimization of these devices and structures is an extremely challenging electromagnetic problem. The analysis of complex electrically large unbounded wave structures using rigorous methods such as method of moments (MoM), finite element method (FEM), and finite difference time domain (FDTD) method can become almost impossible due to the need for large computational resources. Asymptotic high-frequency techniques are used for analysis of electrically large quasi-optical systems and hybrid methods for solving multi-scale problems. Spectral Ray Tracing (SRT) has a number of unique advantages as a candidate for hybridization. The SRT method has the advantages of Spectral Theory of Diffraction (STD). STD can model reflection, refraction and diffraction of an arbitrary wave incident on the complex structure, which is not the case for diffraction theories such as Geometrical Theory of Diffraction (GTD), Uniform theory of Diffraction (UTD) and Uniform Asymptotic Theory (UAT). By including complex rays, SRT can effectively analyze both near-fields and far-fields accurately with minimal approximations. In this thesis, a novel matrix representation of SRT is presented that uses only one spectral integration per observation point and applied to modeling a hemispherical and hyper-hemispherical lens. The hybridization of SRT with commercially available FEM and MoM software is proposed in this work to solve the complexity of multi-scale analysis. This yields a computationally efficient self-consistent HSRT algorithm. Various arrangements of the Hybrid SRT method such as FEM-SRT, and MoM-SRT, are investigated and validated through comparison of radiation patterns with Ansoft HFSS for the FEM method, FEKO for MoM, Multi-level Fast Multipole Method (MLFMM) and physical optics. For that a bow-tie terahertz antenna backed by hyper-hemispherical silicon lens, an on-chip planar dipole fabricated in SiGe:C BiCMOS technology and attached to a hyper-hemispherical silicon lens and a double-slot antenna backed by silica lens will be used as sample structures to be analyzed using the HSRT. Computational performance (memory requirement, CPU/GPU time) of developed algorithm is compared to other methods in commercially available software. It is shown that the MoM-SRT, in its present implementation, is more accurate than MoM-PO but comparable in speed. However, as shown in this thesis, MoM-SRT can take advantage of parallel processing and GPU. The HSRT algorithm is applied to simulation of on-chip dipole antenna backed by Silicon lens and integrated with a 180-GHz VCO and radiation pattern compared with measurements. The radiation pattern is measured in a quasi-optical configuration using a power detector. In addition, it is shown that the matrix formulation of SRT and HSRT are promising approaches for solving complex electrically large problems with high accuracy. This thesis also expounds on new measurement setup specifically developed for measuring integrated antennas, radiation pattern and gain of the embedded on-chip antenna in the mmW/ terahertz range. In this method, the radiation pattern is first measured in a quasi-optical configuration using a power detector. Subsequently, the radiated power is estimated form the integration over the radiation pattern. Finally, the antenna gain is obtained from the measurement of a two-antenna system.