This work aims to study the fundamental principles that govern and control
human movement. To formulate a theory consistent with evolutionary principles
variational calculation methods and techniques from optimal control theory were used to propose
an organizational principle for the movement. The study carried out here restricts the analysis
for movement of the upper limbs of healthy individuals or those without motor pathologies
known. As part of the specific objectives of this work, we can mention the
deepening the study on the minimum start model proposed by Flash and Hogan,
as well as understanding the origin of the scale exponent initially studied by Hoff and
which exhibits a functional dependence between the duration of the movement and the magnitude of its
displacement. Although this model has been widely used due to its
ability to describe and represent the speed profile of movement, this work
argues that it does not have adequate physical or biomechanical foundations and proposes
alternative principles based on the optimization of other kinematic parameters. To the
In carrying out the study, the concept of decomposition of movement elements was used
proposed by Miranda to evaluate the correlation between the proposed theoretical models and the
experimental data collected.

Surface growth is an important out-of-equilibrium phenomenon and has several
technological applications, such as the thin film manufacturing process. Some
information about this phenomenon can be obtained through computer
simulations using lattice models, via the Kinetic Monte Carlo method. In this
dissertation, results of computer simulations will be exposed for discrete models
said to belong to the universality class of the KPZ (Kadar-Parisi-Zhang) and
VLDS (Villain-Lai-Das Sarma) equations. Interfaces that show wrinkling can show
certain statistical quantities that are invariant under scaling transformations,
defining scaling exponents. However, the scale exponents are well defined in the
hydrodynamic limit, because of this, obtaining these exponents is subject to time
effects and finite size. In addition, the existence of an intrinsic roughness that
modifies the Family-Vicsek (FV) scale ratio is reported in the literature, which is
one of the origins of scale corrections for certain models. In order to circumvent
the action of these effects in obtaining the exponents that characterize the scale,
scale correction methods were developed, quoting the extrapolation method
proposed by Aarão Reis. In the present work, we propose a technique applied to
lattice models, which helps to obtain the local roughness exponent. The
technique called TMHP (Transformed Mean Height Profile), consists of dividing
the discrete irregular profile into several bins (compartments of the same size),
to produce a transformed profile of average heights. The profile generated by the
TMHP technique was able to attenuate the stochastic fluctuations of heights in
the regions of valleys and peaks, generating a smoother profile and reducing the
effect of intrinsic roughness on the scale. Furthermore, for compartment sizes
smaller than the correlation length of the original profile, the profile generated by
the technique is equivalent to the original profile, with regard to the scale
exponents. A feature of the TMHP technique is the existence of an optimal bin,
which is the bin size capable of providing a better correction for the local
roughness exponent. In the case of discrete models belonging to the KPZ class,
the results show that the global growth exponent remains unchanged for profiles
generated by TMHP through the optimal bin. However, for bin sizes that exceed
the original profile correlation length, the growth exponent reported by the TMHP
technique is consistent with that of an uncorrelated growth. Finally, it will be
discussed under what conditions there is a connection between the transformed
profile and the one reported through computer simulations of a specific type of
AFM (Atomic Force Microscopy), called electrostatic probe microscopy.

The microsolvation process of ions is relevant in several areas of science and constitutes
the initial step for the study of the formation of ionic molecular clusters, allowing a
better understanding of the physical and chemical properties of the system. In this
dissertation a theoretical study of the microsolvation of the K+ ion by molecules of
CO2 is developed. For this purpose, we use two potential energy surfaces, within the
Improved Lernnard-Jones semi-empirical model, to describe the interaction between the
K+ ion and the CO2 molecule and between two CO2 molecules. Specifically, the difference

between both potentials is in the effective charge of the K+ ion and in the terms of non-
electrostatic interaction between the molecules of CO2. On the other hand, we employ

an implementation of the Genetic (or Evolutionary) Algorithm to determine the lowest
energy stable structures of these clusters. Genetic algorithms, in particular, are a class of
optimization and search methods that simulate evolutionary processes inspired by nature.
In the present study, we used the genetic algorithm to search for stable structures and their
energies (global minimum and local minima) resulting from the process of microsolvation
of the K+ ion by molecules of CO2, allowing us to obtain different information from the
clusters such as, for example, the existence of magic numbers, the formation of the first
solvation layer, symmetry, among others, including highlighting the differences in the
results obtained for the different surfaces of potential energy.
.

In this work we deal with the inclusion of electronic correlation in the elastic scattering
of electrons by molecules using state functions determined with the Configuration Interaction
(CI) Method to describe the target. Using CI and Schwinger Variational Iterative
Method (SVIM) for the scattering of electrons by molecules, we determine the expressions
for the electron-molecule interaction potential in this new context, and we implement
them to obtain the dierential cross sections (Dierential Cross Sections-DCS) for the
elastic scattering of electrons in the energy range from 2 to 10 electron volts (eV) by
non-linear molecular targets (O3, SO2 and CH2N2) and in the energy range of 2 at 11.6
electron volts (eV) for linear molecular targets (OCS, C3 and HCN). Our results, compared
with experimental data and other theoretical results from the literature, show that we
were successful in extending the procedure with the CI Method for non-linear molecular
targets. And although the descriptions made with Hartree-Fock Roothaan (HFR) and CI
have generated similar results for the studied systems, the CI Method as implemented
by us proved to be a procedure that can be used to reproduce and analyse experimental
observations at lower energies, not only for electron scattering processes by linear but also
by non-linear molecule-targets.

In this work, we examined the process of molecular photoionization, which occurs when
the incident photon has enough energy to ionize the molecule. Specifically, we conducted
a theoretical study of the photoionization of the heterocyclic molecules Pyrrole (C4H5N)
and Furan (C4H4O), using the Restricted Hartree-Fock (RHF) and Density Functional
Theory (DFT) methods to describe the isolated target. Particularly, we determined the
photoionization cross-sections and the asymmetry parameter. The results were obtained

using the computational package epolyScat-E. For both molecules, we performed calcu-
lations of the photoionization cross-sections in length and velocity approximation, both

with and without the inclusion of the polarization effect (Perdew and Zunger potential -
PZ), in the energy range between 8.2 and 50 eV. From the obtained results, we observed
that the performance of the two electronic structure calculation methods used in this
work was similar. In general, the cross-sections of the analyzed molecules have common
characteristics, in length form they differ quantitatively from the curves in velocity form.
When we included the polarization potential, the difference between the two forms of the
cross-section was reduced, and there was a shift of the resonance features of the curves in

lower energies. We note that the inclusion of polarization via the PZ potential did not sig-
nificantly improve our results when compared to the experimental data; the cross-sections

in velocity form without polarization were in better agreement with the experimental

results. Regarding the asymmetry parameter, we observed differences between the cur-
ves with and without polarization, but there were no significant differences between the

length and velocity curves. Additionally, concerning the resonance positions, the asym-
metry parameter curve generally has a minimum, while the photoionization cross-section

has a maximum. This work contributes to the research of accurate theoretical methods
that provide reliable values of quantities associated with the photoionization process and
can guide the search for experimental results involving target molecules for which such
data is scarce.

In this work, we calculate the energies and eigenfunctions for the ground state and for some
excited states for systems with two electrons and nuclear charge Z = 0, 1, 2, 3 confined by
an isotropic harmonic potential with confinement intensity given by angular frequency ω.
This is done by using a set of hyperspherical coordinates fixed in space consisting of a
hyperradius and five angles. The use of hyperspherical coordinates suggests the separation
between the hyperradius and the angular coordinates in a similar way to the adiabatic
separation between nuclear and electronic coordinates for a molecule. This gives rise
to a differential equation in angular coordinates and another in radial coordinate. To
solve these equations we use the Finite Element Method (FEM), a method for solving
differential equations belonging to the Variational Methods family. Furthermore, we use
the eigenfunctions thus obtained to calculate the information entropy in position space
associated with the ground state and the first excited state of the mentioned systems. The
variation of entropy with the intensity of the confinement is analyzed. Whenever possible,
our results are compared with results in the literature.

In this work, we revisit the thermal production and annihilation of monopoles and their
relic abundance, exploiting the monopole phenomenology described by the effective field
theory of monopole pair production via Drell-Yan process. We make use the vacuum
cross sections for the Drell-Yan reactions to estimate the cross section averaged over the
thermal distribution associated to other particles that constitute the hot medium where the

monopoles propagate, in our case the early universe environment. Then, we use the ther-
mally averaged cross sections as inputs to estimate the evolution of the Relic Abundance

of monopoles following the freeze-out theory.

In this work we propose a method capable of quantifying the synchronization between
two distinct parameters of a time-varying system, which can be described
using multilayer networks. In this method, we consider connections as a factor
essential in obtaining the synchronization measure. This being evaluated from two
perspectives: the co-occurrence of connections of different parameters in relation to time and,
regarding the attendance of connections.
The construction of this method is based on the concept of networks, as in the first
chapter of this thesis we approach a brief introduction about graph theory and its
basic indices of analysis of a system. The systems considered here exhibit changes
over time, and are evaluated based on different parameters. In view of this,
the concepts of time-varying graphs - GVT [1] and multilayer networks [2–4] also
are discussed in this chapter.
We also present in Chapter 1 a description of the synchronization method by
motifs [5] developed by Rosário and collaborators, which transforms time series into
time-varying networks, as this method will be used in our work. Is for
At the end of the chapter, we present the Incidence and Loyalty indices [6] developed in the
the study of word networks and which served as a basis for the design of our proposal.
Chapter 2 follows the article format and, therefore, the first part is
composed of: abstract, keywords and introduction. In sections 2.2 and 2.3, we present
our methodology and the validations developed. Its application is discussed in the section
next, where we consider the synchronization of different combinations of 4 variables
climatic conditions of the 417 cities of the state of Bahia in a period of 17 years. in the last section
of the chapter, section 2.5, we present the final conclusions about the developed method and
about your application.
Finally, we have two appendices. In the first one, we justify the choice of the values of the
parameters of the motif synchronization method [5]. And, in the second, we discuss
simplified form on the biomes found in the state of Bahia.

In the thermodynamic limit, two gases of confined non-interacting fermions at zero temperature, which differ only by the presence of a local impurity or by a symmetrical potential that decays rapidly with distance, have equal energy densities. In the same limit, their respective ground states, as a consequence of the Anderson Orthogonality Catastrophe, are orthogonal. We study this phenomenology, demonstrate its universality, and develop its analogy with the First Order Quantum Phase Transition.

We present in this work a study of the process of elastic scattering of electrons by molecules, using different methods to target description and different atomic bases. The methods used to determine the functions and static potential that describe the target are the Hartree-Fock-Roothaan and the Configuration Interaction (CI) procedure that takes into account the electronic correlation in the molecules. To describe the polarization effects, the Free Parameter potential and Padial and Norcross model are used. The calculations are performed for the HF, HLi and HCL molecules, with the atomic bases STO-6G, DZV and 6-31G. The resolution of the Lippmann-Schwinger equation is performed with the Schwinger’s iterative variational method (SVIM) and the Differential Cross Section is determined for incident electron energy values between 1.2 eV and 30 eV. The results obtained are compared with each other and with other theoretical results and experimental data available in the literature.

In this work we present a study on Yukawa’s potential in the formulation of the Quantum Theory in Phase Space and the determination of the Wigner Function. With these aims, we consider the system formed by a particle subject to this potential and different procedures. Initially, with the usual Quantum Theory and the approximate solutions obtained by Garavelli and Oliveira and by Hamzavi et al. we determine the corresponding Wigner Functions following the process based on the transformation proposed by Wigner. Next, with Symplectic Quantum Mechanics (SQM), we analyze the system using the Schrödinger Equation in Phase Space (SEPS) characteristic of SQM and the corresponding Wigner Function obtained from it, in two situations: (i) in the three-dimensional case, to compare with the results obtained in the first part, we use the Nikiforov-Uvarov (NU) method to solve differential equations and the star product to determine the Wigner Function; (ii) in the two-dimensional case, due to the lack of results in the literature with this potential , to compare with the case of the Coulomb potential we use the Yukawa potential approximated by an expansion to third order terms in the attenuation factor µ, the Levi-Civita transformation and the phase space perturbation theory. In all cases, the non-classicality factor is determined as a function of attenuation and its behavior analyzed in the region of critical value µc. 

In this work, we studied the photofragmentation of formaldehyde in the gas phase and in the valence region. We fragment or ionize the sample with photons in the energy range of 10 to 21 eV. The technique used was time-of-flight mass spectrometry, associated with the technique photoelectrons and photoions coincidence, PEPICO. Experimental data were obtained at the National Synchrotron Light Laboratory, in the TGM beamline. We constructed partial ion production (PIY) curves for the main formaldehyde fragments (m/q = 30, 29, 28, 2 and 1) and around the opening energy of each channel. The spectra of the relative production of these ions were also presented in the energy range from 10.70 eV to 21.50 eV. We determined the appearance energies of the main fragments produced and the percentage of ions production in the studied energy range. Our results were analyzed and compared with theoretical and experimental results available in the literature. Overall, our results are in good agreement with the results found in the literature.

One of the ways to study the brain is through complex networks, because like many systems in nature, it is also considered a complex system. Functional brain networks (RBN) characterize the brain considering its functionality when obtaining the relationship between its different elements through measures of brain activity. Most of the works on RBN found in the literature have a static approach, without considering brain dynamics. Another problem when studying the brain is the construction of functional networks that use synchronization methods that do not consider a possible delay in synchronizations, because due to the own physiology of the brain, there may be a delay in synchronizations and if we only consider the synchronizations that are in phase, we would be losing information. Rosário et al. (2015), proposed a synchronization method called Motif Synchronization (MS), where it is possible to obtain the time series synchronization for different delays. In this way, the method estimates the delay that occurred for the maximum synchronization between two electrodes, what we call the delay time (DT). The objective of this work is to explore the different characteristics of this index in healthy subjects in baseline conditions, in order to use it as a new index in the characterization of brain functional networks. To this end, we compared the DT in functional brain networks of different individuals, simulating different experimental conditions and exploring three hypotheses: the existence of a characteristic delay time for the studied sample or for different brain regions; the dependence of the DT with the distance between electrodes. In addition to these analyzes, we used the DT to assess the influence of the conduction volume on the Functional Brain Networks. The results show that there is a growing monotonous relationship between distance and delay time. No characteristic delay time was seen for each brain region. There is evidence that the volume conduction influences the synchronization of the nearest electrodes. Some individuals have a greater influence on the volume conduction in more distant regions of the brain. The investigation of the pattern of the distribution of delay times showed that the synchronization between more distant electrodes has little influence on the effect of the conduction volume when compared to the synchronizations of the nearest electrodes and that these distant synchronizations exhibit characteristic DT of 9 ms and 24 ms. The analysis made of the DT distribution, for electrodes distant from the same brain regions, showed that the edges showed shorter delay times compared to the DT distribution for electrodes distant from different areas. We found that the pattern of DT distribution of intra and inter-hemispheric electrode pairs is the same. The different results showed that the delay times between 0 and 1 ms are predominantly due to the volume conduction and that there are characteristic times that will depend on the regions that are analyzed. The results show the importance of the synchronization methods that consider the delay in the synchronizations, as well as obtaining a filtering of the minimum delay times in order to remove connections influenced by the volume conduction.

In this work, we use the Fock space structure to apply thermal field dynamics (TFD - Thermofield Dynamics) in relativistic scattering theory. We start from Dirac's equation as describing a field of relativistic matter; the Fock space structure was applied to the original system and its dual; the Bogoliubov transformation is used to determine the scattering matrix at finite temperature. With this formulation we determine expressions for the differential cross sections (DCS – Differential Cross Section) of the relativistic electron and p ositron scattering processes by atoms at finite temperature, and we perform calculations using these expressions. For the correction of the electrostatic potential we use an analytical shielding function based on the superposition of Yukawa-type potentials. We obtained that the influence of temperature is presented as a correction to the description at zero temperature. This correction has a value of one for temperature equal to zero and tends to a constant value (0.0625) when the temperature tends to infinity; in this limit, the thermal DCS is 16 times smaller than the DCS at zero temperature, a result compatible with data obtained by other authors in the analysis of other systems.

The stable carbon isotope, especially 12C and 13C in natural abundance, is used to examine physiological, ecological and biogeochemical processes related to ecosystems, providing important information. Various processes and environmental factors influence the isotopic composition of plants, such as light intensity, photosynthetic capacity, atmospheric humidity, variation in the CO2 source, simultaneous variation of the light source and the CO2 source, and also, the availability of water. Due to the new possibilities of isotopic measurements using the laser, the natural abundance of 13C is now an excellent tool for studying the ecosystem and plants. An increasing number of studies use isotopic fractionation between carbon reservoirs or an abundance of ¹³C in respiratory CO2 to examine the carbon source of respiration, production of plant biomass or sequestration of organic matter in soils. The 12C/13C ratio associated with plant metabolism is therefore essential for understanding natural isotopic signals. In the present study, the isotopic ratio of carbon in plants collected in three cities in Bahia was studied, and from the isotopic fractionation of d13C and d15N, changes in the isotopic pattern of carbon and nitrogen in leaves bulk were identified. From the results discussed as differences in the isotopic pattern of the leaves bulk of these plants, determined isotopic values of d13C of environmental CO2 in the cities of Salvador, Feira de Santana and Elísio Medrado

The electronic structure, lattice dynamics and electron-phonon coupling of pure, boron and nitrogen-doped diamond carbon were investigated, within the generalised-gradient and virtual crystal approximations. To examine the influence of impurity content and pressure on the superconductivity of these systems, the electron-phonon coupling constant (λ) and the critical temperature (Tc) were calculated, within concentration from 0-15% and pressures from 0-90 GPa. Regarding the boron-doped diamond, the calculations indicated that this system’s electron-phonon coupling strongly relates to the optical phonon modes, and the estimated critical temperatures matched previous theoretical and experimental results. Regarding the nitrogen-doped case, it was observed that both λ and Tc were
larger than those obtained for the hole-doped case. The most distinguishing feature of this system was it’s rising acoustic contribution to the electron-phonon coupling, which led to significant values for λ and Tc. All scenarios presented a decreasing critical temperature with increasing pressure. In opposition to the other cases, the C0.85N0.15 system exhibited a positive dependence between critical temperature and pressure, leading to an estimate of the superconducting transition to happen at 121.92 K, at 20 GPa.

This work uses the Duffin-Kemmer-Petiau theory to study the deformations on scalar DKP and Dirac
oscillators, and two-dimensional oscillators immersed in a magnetic field. Inspired in the Tsallis statistics, we
use the non-minimal coupling with a deformed linear momentum operator and investigate the thermodynamics
of relativistic deformed oscillators, mapping them in a relativistic Morse-like potential, recovering S-wave
states in 1D and 3D systems. We revisit the Kemmer 2D oscillator in an external magnetic field and
investigate the result in the scalar and vector sectors, which in the last one we identified a splitting in
the frequencies. We study the thermodynamics for both systems, as well the ocurrence of phase transition
in coupled-free particle systems. We implement in this system the Moyal product, and corroborated the
non-relativistic regime with Galilean covariance. Finally, we approach the Umezawa formalism in Galilean
covariance, finding non-relativistic linear equations, and discussing the Pauli-Lubanski vector with the
projective operators of the Galilean DKP field.

To understand ecological communities, we must understand the complex dynamical patterns that

emerge from population interactions. Indeed, ecological communities are non-randomly assem-
bled, and the interactions between populations have distinct architectures or topologies. Through

this structure of interactions, populations and species inuence each other's growth in an intricate
manner. These dynamics unveils itself in community-wide emergent properties, such as community

stability. During the last century, many central advancements in ecology stemmed from mathemat-
ical methods based on dynamical systems theory. More recently, the representation of ecological

communities as complex networks, such as food webs and competitive or mutualistic networks,
provided additional insights into the ecology of communities. Several authors contributed to our
current knowledge on the interplay between the structure and dynamics of complex ecosystems.
Despite the extensive developments in this area, many questions are not yet settled. Notably, the
distribution of each type of dynamics (attractors) in ecological models was seldomly studied in
favor of the assumption of equilibrium. Additionally, an approach exploring the ubiquity of known
results linking community stability to structure-related parameters in the parameter space is of

great importance. In this study, we aim at contributing to this endeavor by performing simula-
tions based on the generalized Lotka-Volterra model (gLV) across a wide parameter space range.

In accordance, our research objective is to present an overview of the gLV asymptotic dynamics,
coexistence, and resilience by performing a comprehensive computational exploration integrating
variability in type, intensity, and distribution of interspecic ecological interactions. We found that
dierent dynamics of ecological communities can be described by specic parametrizations of the
gLV, despite a large prevalence of parameter combinations leading to unlimited growth of some
populations in the community. We were also able to detect known patterns, such as the negative

impact of cooperation upon the resilience of communities and the occurrence of competitive exclu-
sion in speciose communities. Signicantly, our research contributes to the longstanding question

of the interconnections between the structure and stability of ecological communities.

In this thesis, in the context of Atomic and Molecular Physics, we present a study about the NaLi and RbCs molecular systems for the ground state. We take a spectroscopic approach using experimentally obtained results for vibrational energies, and we use a mathematical structure constructed from coherent states to construct an eective algebraic Hamiltonian. At this time, we use operators belonging to a particular Lie algebra to determine the mathematical expression used in the calculation of vibrational energy, to be compared with the energies obtained by experimental methods. Thus, we want to calculate the linear parameters, which will be used to calculate the dissociation energy, the range and consequently the construction of the Potential Energy Curves of the molecular systems under study. For minimization of experimental and calculated energies, we use fortram coding, whose purpose is to obtain such parameters, as well as to obtain the results of the algebraically calcula- ted energies. In algebraic computation we will make an adjustment for the minimization between energies, such that they will be used in the construction of the agenic potential. To construct the Potential Energy Curves, we will use a Morse type expansion, in which we will have as elements values associated with the number of bound states of each molecular system and the number of expansion terms. Thus, oer to the academic community a theoretical material with reference in experimental data about the NaLi and RbCs molecules, using an elegant mathematical formalism that can contribute to the dissemination of knowledge to the actors involved in pure and applied research in physics or related elds.

In recent years, interest in the production of transparent oxide films has grown
because of the many technological applications of theses oxides in the industrial
production of electronic devices that use visualization display, gas sensors and
electrodes in solar cells. Among the transparent oxides, indium oxide is the most
widely employed because of its excellent optical and electrical properties. However,
the large-scale use of indium oxide has been increasingly limited by the high cost of
Indium ores. Due to its improved optical and electrical properties, low cost, high
thermal and mechanical stability, fluorine doped oxides (SnO2: F) have proved to be
one of the most promising materials as an alternative to indium oxides. Therefore, in
the present work it is reported the construction of an experimental workbench that
allows the production of SnO2: F films with thickness controlled by the spray pyrolysis
deposition method. The control of the film thickness was achieved by the simple
adjustment of the spray nozzle height, showing a strong linear correlation (R = 0.999)
between this adjustment and the film thickness. The SnO2 films produced in the
experimental setup had thicknesses in the range of 520 to 1240 nm and their
morphological, textural, structural, optical and electrical properties. were
characterized. In the morphological and textural characterizations, from the images
obtained with MEV and AFM, the films were homogeneous and with granular
appearance, presenting values of average roughness (Ra) and average grain size in
the range of 92.1 to 121.6

The objective of this work is the analysis of axial resonances and exotic states in
sectors of the foreigner, botomônio and charmônio. We use a method that
the exact QCD Hamiltonian in the Coulomb gauge by an effective Hamiltonian with
a confining potential and a transverse hyperfine interaction. A transformation
of similarity (BCS) is applied, diagonalizing the Hamiltonian in a new base of
quasiparticles. We apply, then, variational calculations to obtain the equation of
the quasiparticle mass gap, and we used the RPA and the TDA to represent the
excited.

In this work, we present a new Double Zeta (DZ) atomic basis set for the boron atom. This atomic basis set was obtained using the HFGauss-GSA algorithm, which is a direct minimization procedure of the Hartree-Fock functional. This algorithm is based on the Generalized Simulated Annealing method. This algorithm does not solve necessary condition equations nor does it use orbital occupation rules, guaranteeing, in principle, obtaining the absolute minimum of the electronic energy functional. The HFGauss-GSA algorithm considers as arguments of this functional the coecients and exponents of the Gaussian functions, that dene the functions of the atomic base, and the coecients of the LCAO expansion. We analyze the convergence characteristics of the HFGauss-GSA algorithm as a function of the parameters qV and qT , responsible for the behavior of the probability of visitation and "temperature"functions, respectively; and we realize that there is no ideal value for the pair (qV , qT ) that will ensure that the algorithm always converges. We performed HF calculations for the BH molecule with dierent spin multiplicities using the DZ atomic basis set presented here and the traditional DZ atomic basis set. With the obtained results, we constructed curves of the total energy versus the interatomic distance for this molecule. Calculations were also made to obtain multiple HF solutions for the BH system in order to analyze the possible changes introduced in the energy hypersurface. 

The current work presents a study of the soliton solutions using the Bilinear Hirota Method for the integrable models of the non-linear equations of Korteweg and de Vries (KdV), modi ed Korteweg and Vries (mKdV) and Non-Linear Schrödinger (NLS ) in (1+ 1) - dimensions. We extend the KdV equations for (2 + 1) - dimensional models and and their soliton solutions. Also with the use of the Bilinear Hirota Method, we studied the dromions solutions of the KdV equation in (2 + 1) - dimensions and a graphical analysis was made from the obtained results, using the software MAPLE18.

In this work we calculate dynamical invariants using the equations of motion of a
quantum mechanical system and the Schwinger formalism. Both approaches turn out

to be complementary, the second being more fundamental than the first one. The cal-
culations of the invariants are, initially, for the harmonic oscillator with time-dependent

frequency, for oscillators with higher dimension and, at the end, for the one dimensional

time-dependent, damped, driven harmonic oscillator. With the linear invariants associa-
ted with the equations of motion and under the existence condition of solutions for the

diferencial equations of the parameters, it is possible to obtain a new way of canonical

quantization for the one-dimensional oscillator-type systems. This new procedure requi-
res the identification of the linear invariants with ladder operators, which makes possible

to obtain the Hilbert space of the system.

Magnetic fluid hyperthermia (MFH) is a recent cancer treatment technique that has gained recognition for its effectiveness in preserving healthy cells. Its use is broad and advisable for tumors of low accessibility, as is the case of glioblastoma multiforme (GBM), the most frequent and aggressive brain tumor. Despite the studies done on MFH and GBM, the presented approaches have limitations, be they ethical, economic or technological. Therefore, the objective of this paper is to develop an agent-based computational model to emulate the diffusion of temperature in the neoplastic tissue medium submitted to the treatment of MFH, which may indicate new directions for treatment optimization.

Heavy mesons play an important role in understanding strongly interacting matter. Quarkonia (such as charmonia and bottomonia) that survived the plasma phase of quarks and gluons are expected to collide with other particles that make up hadronic matter. In this paper, we present a study on the interactions of the Upsilon meson with a hadronic medium. The meson-meson interactions are described by an effective lagrangian that is based on a theory of chiral perturbation extended to SU (4) symmetry, which gives the amplitudes of unitarized coupled channels projected in s-waves. The symmetry is explicitly broken for SU (3) by suppressing the meson-driven interactions consisting of quark b. We calculate the shock sections for scattering by pseudo-scalar and vector mesons, as well as their inverse processes. Maintaining the validity of this current approach in the low energy CM range, the most relevant channels are evaluated.

nderstanding the evolutionary process of the universe, from the formation of simple molecules to more complex molecules, has been a topic widely discussed in the scientific community. In astrobiology it is believed that cyclic organic compounds may have played an important role in the evolution of life on earth, having important prebiotic functions. One way to quantify photochemical processes is by determining
of the photoabsorption shock section. Particularly, the knowledge of the absolute absorption shock section for complex polyatomic species generally permeates a certain experimental action. In this context, we performed an experimental investigation of photoabsorption and photoionization processes through the interaction of synchrotron radiation in the
vacuum ultraviolet region in heterocyclic organic molecules in the gas phase. Specifically, we are interested in studying the simplest 6- and 5-membered fundamental molecules, namely Pyridine, Pirrol, Furano and Thiophene, for their importance in understanding the synthesis of more complex cyclic species in the interstellar medium. The measures
Experimental experiments were performed at the National Synchrotron Light Laboratory, Campinas-SP, using the technique of the Dual Ionization Chamber. With this technique it was possible to measure the photoabsorption shock sections from the first ionization threshold up to 21.5 eV, and the quantum photoionization efficiency. Photoionization and decay shock sections
neutral scale were then derived from this data. In addition, a theoretical study was performed using Schwinger's Iterative Variational Method (SVIM) and the PolyScat computational package to calculate Pirrol's photoionization shock section. Additionally, the absolute partial photoionization shock (PICS) section was determined for
each fragment of Pyridine, from the product of the photoionization shock section (oi) with the respective relative productions of the different ions. The sum rule was also used to calculate the static polarization value of electric dipole for these molecules.
Comparisons are made with experimental and theoretical data available in the literature.

The microsolvation has been subject of intense theoretical and experimental study

with implications in diverse areas such as atmospheric chemistry, biological processes, per-
meation and transport membrane, among others. Therefore, this thesis aimed to develop a

study of the microsolvatation of ions through noble gases. One of our specific goals is to
survey the microsolvatation of ion Li+by argon, kripton and mixture of these atoms. For this

construction, analyses involving the interaction construction of two and three-bodies metal-
alkaline ions with noble gases, from the fitting of potential functions ab initios on the eletronic

energy using the methodology CCSD(T). The determination of stable clusters structures will
be given by the application of the evolutionary algorithm (EA). The evolutionary algorithm
will search of these low energy structures, both in global and local minima. In order to
strengthen this study, pos-optimization calculations using the ab initios CCSD(T) and MP2
methods are also performed. Treatment of clusters with noble gases of higher numbers, a
DFT methodology is also used in the stage of pos-optimization, with the goal to perform a

Benchmark analysis of these systems. Lastly, from diverse local minima generated by evo-
lutionary algorithm we applied a Machine Learning technique to enable the determination

of choose rules of the better EA minima that present an efficient description of the energy
landscape from the clusters length.

In this work, we have theoretically proposed Creutz-Taube coordination complexes,
with formulae [(HN 3 ) 5 -Co-py-X-py-Ru-(NH 3 ) 5 ] q+ , assuming different ionic charges, q,
and spin multiplicities, compatible with the metal ions involved and with X = C≡C and
C 60 . The main aim was to replace the central part of the bridge ligand between Co and
Ru ions with a C 60 molecule. From electronic structure calculations within the scope of
the Density Functional Theory (DFT), we have performed a systematic computational-
theoretical investigation to examine the new coordination complexes. It is of both
theoretical and experimental interest to investigate the electronic properties of
coordination complexes containing mixed valence, aiming at potential technological
applications. In this context, we have also investigated the feasibility of using fullerene-
containing ligands in the coordination complexes to control electronic excitations and
transfer between metal centers with different oxidation states. Our calculations allowed
us to assess whether fullerene can facilitate or hinder electron relocation between two
metal centers. In order to make our computational simulations possible, we use start
with a typical geometry occurring for these types of complexes, with crystallographic
data available in the literature. In addition, we have performed a study of a standard
complex (containing -C≡C- in the bridge ligand) to compare our results with the new
proposal containing C 60 . In this sense, as generally as possible, we investigated several
theoretically acceptable possibilities for the C 60 fullerene-mediated coordination
complexes (Creutz-Taube-type) and Co n+ and Ru m+ metal ions in their different oxidation
states and spin multiplicities. In summary, our main model systems were described by
the formulae [(NH 3 ) 5 Co-py-C 60 -py-Ru(NH 3 ) 5 ] q+ (q = 4, 5 and 6; q = n + m). As is known,
such complexes constitute a motivating theoretical challenge, since the investigation of
their electronic properties allows a detailed analysis of the essential properties for the
electronic transport between the metallic centers, as well as for the understanding of the
electronic spectroscopy of these complexes. Thus, we could infer about the valence
tautomery mechanism in the case of the [(NH 3 ) 5 Co-py-C 60 -py-Ru(NH 3 ) 5 ] 5+ complex.
Finally, we have established a systematic analysis of the electronic properties as well as
the influence of C 60 on the valence tautomerism and electronic properties in general.

We present in this dissertation some new results for the development of the relativistic
quantum theory within the algebraic approach proposed by Schönberg and developed
latter by Bohm, Hiley, Fernandes and Vianna and other autors. Firstly, by exploring the
DKP equation in the Bohm, Hiley, Fernandes and Vianna’s approach we have shown its
equivalence with the Klein-Gordon-Fock equation and the Proca equation; we also have
shown this algebraic formalism extend naturally the Kruglov approach of the non-massive
DKP equation including the 0-spin case. In the sequence we extend Schönberg’s formalism
to obtain DKP algebra by introducing a method, via equivalence class, to extract the
ParaDKP algebra (PDKP algebra) of the symplectic Clifford algebra of phase space; in
consequence of this methodology we have found symplectic versions of Klein-Gordon-Fock
like, Dirac like and DKP like equations. We also have developed a superalgebra in which
bosons and fermions are handled in a unified way and we have shown how to extract from
this algebra the Clifford superalgebra and the DKP superalgebra. In this approach we
proposed Klein-Gordon-Fock like, Dirac like and DKP like superequations. Finally we
have shown how the quantum field theory could be included in this formalism by using
the distributions and algebra bundles mathematical structures.

The Fierz-Pauli-Gupta field equation (FPG) is developed in the generalized phase
space proposed by Bohm and Hiley. The Dirac and DKP algebras are considered in a process
of complexification in order to construct Clifford algebras associated to the generators of
FPG field algebra. Free particles and interacting with an external electromagnetic field
are analyzed from the Liouville equation obtained for the studied cases.

In this work, having as motivation the investigation of strongly interacting matter under extreme conditions, we study the thermodynamic behavior of systems consisted of bosons and / or fermions in a medium of other particles, via the approach of effective field theories at fi nite temperature. In particular, we use the Walecka model in order to describe the phase scalar and spinal, which may be associated with scalar mesons and baryons, respectively, subject to certain conditions. We see the effects of size finite, the geometry of the system and the influence of an external uniform magnetic field on the phase structure. We find a peculiar diversity of diagrams that exemplify as the presence of these parameters modifies the phase dynamics, either in the intensity transition regions or even the nature of phase transitions.

ease in world energy demand and the impact of energy production, from the of fossil fuels, about the environment has raised discussions about the use of renewable energy sources. This has fostered research in order to make feasible, cheap and diffuse its use in energy production. it is in this spirit that this work follows, bringing the proposed assembly of solar cells from the fi film technology in semiconductors. This is an alternative to traditional solar cells manufactured with silicon, aiming at reducing the cost-benefit ratio for energy production solar. The assembly structure developed here follows the stacking of the following layers: selective window / buér / absorber / metal contact. The most important layer of this assembly is CuInSe2 (CIS), grown here through cathodic electrodeposition, which is a p-type, polycrystalline, direct-gap (1 eV) semiconductor and has a high coefficient absorption in the visible region of the electromagnetic spectrum. In this paper, the whole process of growth and experimental characterization for this material, using: X-ray diffraction (XRD), Raman and optical spectroscopy, electron microscopy (SEM), energy dispersive spectroscopy (EDS), force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). In addition to the experimental study, crystalline CIS has also been studied theoretically, using principles, implemented by the VASP code. Thus it was possible to determine some of the its physical properties, namely: structural, electronic, optical and dynamic properties network. Also, a theoretical study was carried out, based on the classical theory of nucleation, in order to understand the process of nucleation and growth of the film, by diffusive processes during its electrodeposition, in an electrolytic cell at three electrodes.

For the buffer layer, the ends of In2Se3 (IS) were tested, as well as the ends of CdS, both grown by cathodic

 electrodeposition. The first one is a n-type, polycrystalline and polymorphic semiconductor, with experimentally 

determined gap to 1.38 eV. This film was observed in a mixture of hexagonal and rhombohedral phases and, 

after the heat treatment, at 300 ° C, also showing traces of the second phase fime is also a n-type, polycrystalline

 semiconductor with experimentally determined gap to 2.3 eV and lattice structure that can crystallize with two 

distinct symmetries: zinc blend, or hexagonal vurtzite. Here, it was observed that the CdS crystallizes 

An experimental study of the absolute photoabsorption, photoionization, neutral decay and
quantum yield in the vacuum ultraviolet range of formaldehyde (H2CO) and formic acid
(HCOOH) in the gas phase were performed.
The measurements were done at D05A-TGM beamline of the Brazilian Synchrotron
Laboratory (LNLS) using the double ion chamber technique. TGM beamline has a toroidal
monochromator and a neon filter to cutoff high harmonics photons in the range of energy
studied. The double ion chamber technique allows to obtain absolute photoabsorption cross
sections directly – with this information and the quantum yield, the photoionization and
neutral decay cross sections are easily calculated. Experimental results founded in the
literature of formaldehyde photoabsorption cross section in the same energy range have low
resolution and probably have the contribution of higher energies photons due higher
harmonics.
Theoretical studies of the formaldehyde photoionization cross section found reported in the
literature have a discrepancy with the experimental spectrum of the present work. A
theoretical study, using a computational code based on the iterative Schwinger variational
method (SVIM), observed discrepancies were reduced.
Experimental absolute cross sections results obtained to formic acid have the same profile of
the values found in the literature, although they present a certain discrepancy. The calculation
of the dipole static polarizability using the sum rule TRK for formic acid, obtained from the
cross section photoabsorption spectrum, indicates greater reliability of the results obtained in
this work.

In this work, the results of the growth of thin films of copper oxide are presented, using the techniques of thermal treatment, Sputtering, SILAR and Electrodeposition, for applications in photovoltaic devices. The thin films of copper oxide, in Cu2O and CuO phases, present p-type semiconductivity, gap energy within the photovoltaic conversion range. Among the techniques employed in this work, the electrodeposition was the one that presented the best results for the grown films. We obtained homogeneous thin films of Cu2O, with gap energy in the range of 2.4 eV. The thin films were annealed in order to obtain the CuO oxidation phase of the copper oxide. For the film annealed at 400oC, we achieved complete phase change with a 1eV gap energy film. The films grown by electrodeposition as deposited and annealed were characterized by several experimental techniques such as Raman, SEM, EDS, XPS, optical spectroscopy, Mott-Schottky, hot probe and XRD. The experimental data obtained with some of these techniques were compared with the results of the theoretical calculations performed in this work with the DFT-PBE. As a result of this work we obtained Cu2O and CuO thin films, with excellent properties and promising properties for applications in photovoltaic systems.

The research developed in this doctoral thesis is inserted in the Quantum Theory
of Angular Momentum. In this work we discuss the theory of coupling and re-coupling of
angular momentum in the study of the so-called 3nj symbols. The geometric representations
of tree and Yutsis were exploited as well as their mathematical properties. Another explored
point was the on-screen representation of the Caustic Curve, which is directly related to the
symbol 6j. The studies covered angular momentum re-coupling coecients, encompassing
the problem of the four bars, Regge symmetry, analysis and problem solving of spin networks.
Among the contributions, we can mention the connections of the projective geometry with
the Quantum Theory of Angular Momentum and the projective planes of Fanno, Desargues
and Levi.

The evolution of electronic devices haven’t been following the growth of demand upon
the processing capacity and consumption decrease. This situation open a space for a new
modality of devices based on magnetic semiconductors, that are promissing in the demands
of processing and consumption. The oxide-diluted magnetic semiconductors (O-DMS)
can exhibit room temperature magnetic properties and this feature makes it a potential
alternative to apply in spintonics. Based on this problem, this work proposed to produce
tin oxide (SnO2) such as O-SMD using Co or Ni doping, at different concentrations,
using the spray pyrolysis, because is a simple and inexpensive technique and very used
by research group comprising this work, which is the pyrolysis of spray. In addition,
was proposed to characterize the produced samples, evaluating structural, morphologic,
optical, electrical and magnetic properties and the results could be contrasted with a
theoretical approach based on the Density Functional Theory (DFT), also developed in
this work. The results of the characterizations confirmed the effectiveness of the technique
in producing the SnO2, noting that magnetism has already been found in undoped sample,
induced by defects in the structure of the film. It was observed the doping influence on
the films properties, including their interference on magnetic properties. The theoretical
approach, which was generally compatible with the experimental results, allowed an
understanding of the dopants and defects influence on SnO2 properties, such as show
how the magnetism in this semiconductor oxide is established. As a consequence, there
was a better experimental results understanding. However, the work developed shows the
spray pyrolysis as a potential technique to SnO2 production, because this films deposited
combine interesting electrical, optical and magnetic characteristics for applications in
devices. With production enhancements, the spray pyrolysed transition metal-doped SnO2
must assume some characteristics that will put it directly into the spintronic perspectives.

In complex systems, modeling, based on fundamental laws to determine the behavior of dynamic systems, constitutes an essential aspect of methodological choice, especially if dealing with a non-linear system. An alternative to overcome this difficulty is the use of strategies and procedures aimed at determining the most appropriate mathematical models to the observed conditions based on theoretical and experimental partial system data. In perspective, Artificial Neural Networks RNA are computer-based techniques inspired by a mathematical model of intelligent neural structure bodies, having an information processing complex and highly non linear system which performs calculations in parallel, and acquires knowledge by experience, including applied in recognition processes / pattern classification, used as a tool in this work. The interest lies in the fitting of potential energy curves related to the treatment of reactive scattering H + LiH, a process that is of interest in literature, since the formation and depletion of LiH species may have played an important role during the evolution of the early universe. Therefore, in order to obtain results for the analyzed situation, the nonlinear mapping chosen were the Radial Basis Function RBF, consisting of a arbitrary basis of determine the likely patterns associated with the input vectors, enabling the construction of mathematical models from the training processes and recognition of the RNA. The successful outcome, to the geometries and conditions considered, can be observed in proximity of the data fit with the data used for learning and testing