The existence of a Fisk-type heliospheric magnetic field (HMF) is one of the most debated questions in cosmic-ray modulation. Recently, Burger and Hitge [2004] developed a divergence-free Fisk-Parker hybrid magnetic field model to demonstrate the behaviour of cosmic rays in the heliosphere due to such a field. This approach has been refined and the properties of the consequent field are investigated. It is found that randomly directed magnetic field diffusion in and above the photosphere significantly influences the solar magnetic field both at the solar poles and near the polar coronal hole boundary. The solar cycle dependence of this field is investigated, a study which is of particular importance for studies of the long-term behaviour of cosmic rays, such as those undertaken at the SANAE base in Antarctica. The amplitudes of the 26-day recurrent cosmic-ray variations are modelled as function of both latitudinal gradient and heliolatitude and are found to agree qualitatively and in some cases quantitatively with the observational results reported by Zhang 119971 and Paizis et al. 119991. Although magnetic field data do not clearly indicate the existence of the Fisk field [see, e.g., Fursyth et al., 20021, this study supports the existence of a Fisk-type HMF. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2006.

Cette thèse est consacrée à l'étude de certaines questions de convergence et de récurrence multiples en théorie ergodique. Nous distinguons les systèmes munis d'une transformation et ceux munis de plusieurs transformations qui commutent. Dans les premiers, le mécanisme de facteurs caractéristiques et les nilsystèmes jouent un rôle important dans l'étude de convergence et de récurrence multiples. À l'aide de ces outils, nous étendons les résultats sur la convergence de moyennes ergodiquesmultiples pondérées de Host et Kra pour le cas linéaire au cas polynômial. En conséquence, nous montrons que pour toute fonction $f$ mesurable bornée sur un système ergodique, la suite $(f(T^n x))$ est universellement bonne pour presque tout $x$. Quand il y a plusieurs transformations qui commutent, à l'aide de la machinerie des systèmes magiques introduite récemment par Host et développée dans cette thèse, nous étendons les résultats sur la convergence de moyennes ergodiques multiples sur les cubes de Host et Kra avec une transformation à plusieurs transformations qui commutent. Nous obtenons aussi un résultat de récurrence multiple quantitatif pour deux transformations qui commutent, similaire en faveur du cas d'une transformation établi par Bergelson, Host et Kra / This thesis is devoted to the study of some questions of multiple convergence and recurrence in ergodic theory. We distinguish between systems endowed with a single transformation and systems endowed with several commuting transformations. In the former, characteristic factors and nilsystemsplay an important role in the study of multiple convergence and recurrence. Using these tools, we extend results on convergence of weighted multiple ergodic averages of Host and Kra for the linear case to the polynomial case. As a consequence, we show that for any bounded measurable function $f$ on an ergodic system, the sequence $f(T^n x)$ is universally good for almost every $x$. In systems endowed with several commuting transformations, we use the machinery of magic systems introduced recently by Host and further properties of magic systems developed in this thesis,to extend results of Host and Kra on convergence of multiple ergodic averages along cubes with a single transformation to commuting transformations. We obtain a quantitative multiple recurrence result for two commuting transformations, similar in flavour to that of a single transformationestablished by Bergelson, Host and Kra, but with a different conclusion

In the spinal cord, an intricate neural network generates and coordinates the patterning of limb movements during locomotion. This network, known as the locomotor central pattern generator (CPG), comprises of various cell populations that together orchestrate the output of motor neurons. Identification of CPG neurons through their specific gene expression is a valuable tool that can provide considerable insight to the character, intrinsic properties and role of a population, which represents a step toward understanding locomotor circuit function and correlating neural activity to behaviour. We selectively targeted two inhibitory CPG populations to investigate their molecular characteristics, circuitry and functional role; Renshaw cells (RCs) marked by their specific expression of the cholinergic nicotinic receptor α2 (Chrna2) and a subset of the dI6 population derived by their selective expression of the Doublesex and mab-3 related transcription factor 3 (Dmrt3). We found that RCs have hyperpolarisation-activated cation (Ih) and small calcium-activated potassium (ISK) modulatory currents that differentially regulate their excitation and firing properties, which influence the instantaneous feedback to motor neurons through the recurrent inhibition circuit. Due to previous difficulties isolating RCs from the surrounding locomotor circuits, their functional role remains poorly defined. For the first time, we selectively silenced RC inhibition and found that all aspects of motor behaviour, including coordination and gait were normal. The deletion of RC signalling instead altered the electrical and synaptic properties of the recurrent inhibitory circuit, suggesting that developmental plasticity compensates for the loss of RC inhibition. We reveal Dmrt3 neurons comprise a population of glycinergic inhibitory, spike-frequency adapting commissural interneurons active during locomotion. Conditional silencing of the Dmrt3 population resulted in considerable gait abnormalities in the neonatal and adult mouse. This manifested as an uncoordinated CPG output in vitro, impaired limb coordination in pups and increased fore- and hindlimb synchrony in adults that was exacerbated at faster locomotor speeds. Dmrt3 mediated inhibition subsequently impacts locomotion and suggests the Dmrt3 population contribute to coordinating speed dependent left-right limb alternation. This thesis provides cellular, circuit and behavioural insights into the Renshaw cell and Dmrt3 populations and enhances our knowledge regarding their probable function within the locomotor CPG.

Affective computing has gained significant attention from researchers in the last decade due to the wide variety of applications that can benefit from this technology. Often, researchers describe affect using emotional dimensions such as arousal and valence. Valence refers to the spectrum of negative to positive emotions while arousal determines the level of excitement. Describing emotions through continuous dimensions (e.g. valence and arousal) allows us to encode subtle and complex affects as opposed to discrete emotions, such as the basic six emotions: happy, anger, fear, disgust, sad and neutral. Recognizing spontaneous and subtle emotions remains a challenging problem for computers. In our work, we employ two modalities of information: video and audio. Hence, we extract visual and audio features using deep neural network models. Given that emotions are time-dependent, we apply the Temporal Convolutional Neural Network (TCN) to model the variations in emotions. Additionally, we investigate an alternative model that combines a Convolutional Neural Network (CNN) and a Recurrent Neural Network (RNN). Given our inability to fit the latter deep model into the main memory, we divide the RNN into smaller segments and propose a scheme to back-propagate gradients across all segments. We configure the hyperparameters of all models using Gaussian processes to obtain a fair comparison between the proposed models. Our results show that TCN outperforms RNN for the recognition of the arousal and valence emotional dimensions. Therefore, we propose the adoption of TCN for emotion detection problems as a baseline method for future work. Our experimental results show that TCN outperforms all RNN based models yielding a concordance correlation coefficient of 0.7895 (vs. 0.7544) on valence and 0.8207 (vs. 0.7357) on arousal on the validation dataset of SEWA dataset for emotion prediction.

Dois problemas de planejamento de trajetórias são tratados nesta dissertação, sendo um discreto e outro contínuo. O problema discreto consiste em estabelecer todos os estados intermediários de uma trajetória para levar um conjunto de quatro blocos de uma posição inicial à uma posição meta. O problema contínuo consiste em planejar e controlar a trajetória do braço mecânico PUMA 560. A classe de modelos que se utilizou nesta dissertação foram os modelos parcialmente recorrentes. O problema discreto foi utilizado com a finalidade de comparar os seis modelos propostos, buscando obter um modelo com bom desempenho para resolução de problemas de produção de seqüências temporais. Para o problema contínuo aplicou-se apenas o modelo que apresentou melhor desempenho na resolução do problema discreto. Em ambos os casos são apresentados como entrada para a rede, o ponto inicial e o ponto meta. Dois tipos de testes foram aplicados as arquiteturas: teste de produção e de generalização de seqüências temporais. Para cada problema foram criados quatro tipos distintos de trajetórias, com graus de complexidades diferentes. Para o problema discreto, em média, a arquitetura com realimentação da camada de saída para a camada de entrada e da camada de entrada para ela mesma, todos-para-todos, foi a que apresentou menor número de épocas e também os menores valores de erro durante o treinamento. Foi o único que conseguiu recuperar todos os padrões treinados e de forma geral apresentou melhor capacidade de generalização. Por isto, este modelo foi escolhido para ser aplicado na resolução do problema contínuo, tendo bom desempenho, conseguindo reproduzir as trajetórias treinadas com grande precisão. Para o problema discreto todos os modelos apresentaram baixa capacidade de generalização. Para o problema contínuo o modelo abordado apresentou-se de forma satisfatória mediante o acréscimo de ruído. / Two trajectory planning problems are discussed in this work, one of them being discrete and the other continuous. The discrete problem consists in establishing all the intermediate states o f a trajectory to move a set of four blocks from a initial to a goal position. The continuous problem consists in planning and controlling the trajectory of the PUMA 560 mechanical arm. The class of models utilized in this work were the partially recurrent models. The discrete problem was used in order to compare the six proposed models, aiming at the acquisition of a model with a good performance for the resolution of production of temporal sequence problems. For the continuous problem, only the model that presented better performance in solving the discrete problem was applied. The initial and goal point are presented as input for the network in both problems. Two types of tests were applied to the architectures: production and generalization of temporal sequence tests. Four distinct types of trajectories with different complexity levels were created for each problem. In average, for the discrete problem, the architecture with feedback from the output to the input layer and from input layer to itself all-to-all presented the lowest epoch number in addition to the lowest error values during the training. This was the only model that managed to recover all the patterns trained and in general presented better generalization capacity. For this reason, this model was chosen to be applied in the resolution of the continuous problem. It presented a good performance to the production of mechanical arm trajectories, managing to reproduce the trained trajectories with great accuracy. For the discrete problem, all the models presented low generalization capacity. For the continuous problem, the approached model presented itself in a satisfactmy manner by means of noise addition.

As piodermites, superficiais ou profundas, representam uma das dermatopatias caninas mais comuns no cotidiano da clínica dermatológica de cães. Dentre as classificadas como superficiais, destacam-se a foliculite bacteriana e a piodermite esfoliativa ou superficial disseminada, que representam a grande maioria dos casos. Em alguns cães, as piodermites superficiais são idiopáticas, apresentam evolução crônica e caráter recidivante. A despeito de criteriosa investigação acerca de sua possível etiologia, por vezes, não se consegue evidenciar a causa para a instalação e recorrência do quadro mórbido. Tais animais apresentam frequentes recidivas, em variáveis períodos de tempo, após o término da terapia antibiótica. Para estes caninos, na bibliografia médico-veterinária há recomendação de emprego das controvertidas imunoterapia ou de antibioticoterapia sob a forma de pulsos. Portanto, objetivou-se na casuística do Serviço de Dermatologia do Hospital Veterinário da USP, determinar as principais espécies bacterianas envolvidas, a susceptibilidade destas frente a diferentes antimicrobianos, bactericidas ou bacteriostáticos, assim como, comparar a eficácia e a segurança de três distintos protocolos terapêuticos no manejo a longo prazo, de piodermites superficiais recidivantes idiopáticas. Utilizaram-se 23 animais, de quaisquer dos sexos, de distintas raças e faixas etárias. A amostragem foi aleatoriamente disposta em três grupos de experimentação (GI, GII, G III), respectivamente submetidos à imunoterapia com bacterina comercial (Estafilin®) e às pulsoterapias de \"finais de semana\" ou em \"semanas alternadas\", empregando-se cefalexina \"per os\". O principal patógeno, em 67,6 % da totalidade de isolamentos bacterianos, foi Staphylococcus intermedius. Evidenciou-se (32,4 %), ainda, as espécies S. hyicus, S. schleiferi subespécie coagulans, S. warneri e Micrococcus sp. Segundo os antibiogramas, os fármacos mais efetivos in vitro foram a amoxicilina associada ao clavulanato de potássio, a cefalexina e o ceftiofur. Verificou-se resposta plena em percentis de, respectivamente, 50,0 %, 33,3 % e 28,6 % nos Grupos II, III e I; destarte, ao se agrupar as respostas plena e moderada evidenciaram-se valores relativos de, respectivamente, 83,3 %, 50,0 % e 42,9 %. À luz da estatística (Teste do Qui Quadrado), não se observaram quaisquer diferenças estatisticamente significativas (p > 0,05) entre os percentuais de resposta aos três protocolos empregados. Todos eles mostraram-se seguros, sem acarretar efeitos adversos farmacodérmicos. / Superficial and deep pyodermas are common canine skin disorders in the small animal dermatology practice. Among the superficial form, the bacterial folliculitis and superficial spreading pyoderma represent the great majority of cases. Some dogs are affected by idiopathic, chronic and recurrent type of superficial pyoderma. Despite a rigorous search for possible reasons for its etiology, sometimes it is not possible to determine an underlying cause for the disease recurrence. At variable time periods, these dogs show frequent recurrent episodes, after the interruption of antibiotic therapy. For these patients, the veterinary medicine literature recommends the use of the controversial immune therapy or antibiotic pulse therapy. Thus, using the University of Sao Paulo / Dermatology Service\'s casuistry the present study aimed to determine the major bacterial species responsible for pyodermas, their susceptibility to several bactericidal and bacteriostatic antibiotics as well as compare the efficacy and safety of three different therapeutics protocols for the long term management of idiopathic recurrent superficial pyoderma. A total of 23 male and female, purebred dogs from different ages were randomly allocated in three distinct experimental groups (G I, G II and G III), respectively treated with bacterin immune therapy, \"weekend\" antibiotic pulse therapy and \"week on - week off\" antibiotic pulse therapy, receiving cephalexin PO. S. intermedius was identified from 67,6 % of the totality of bacterial isolates and the remaining 32,4 % was composed of S. hyicus, S. schleiferi subspecie coagulans, S. warneri and Micrococcus sp. According to the antimicrobial susceptibility results the more effective drugs were amoxicillin plus potassium clavulanate, cephalexin and ceftioufur. In percentage values a full response of 50,0 %, 33,3 % and 28,6 % was achieved in Groups I, II and III, respectively. On the other hand, when the comparison was made considering full and moderate together the values were 83,3 %, 50,0 % and 42,9 % for Groups I, II and III, respectively. Through a statistical analysis (Qui score test) no significant difference (p > 0,05) among the response to treatment percentage values was observed for the three groups. All treatments were secure and no drug eruption side effects were observed.

Processsos de renovação são um caso especial de processos pontuais envolvendo eventos recorrentes nos quais um item ou unidade, após a ocorrência de uma falha, é recolocado na mesma condição de novo. Devido a essa propriedade os tempos entre ocorrências para um processo de renovação são independentes e a sua função intensidade é dada pela função de risco. Fatores que interferem nos tempos de recorrência de unidades distintas, ou indivíduos, e que não são observados, podem ser modelados com a inclusão de um termo de fragilidade no modelo. Neste trabalho é apresentado o desenvolvimento de um modelo de regressão para um processo de renovação com tempos entre ocorrências com distribuição de Weibull. Na modelagem foi considerada, ainda, a presença de censuras e a inclusão de um termo de fragilidade para explicar a relação existente entre os tempos de recorrências de uma unidade. A metodologia é desenvolvida para o caso em que várias unidades são acometidas por eventos recorrentes. Nas simulações realizadas foram analisadas as probabilidades de cobertura empíricas do intervalo de confiança normal assintótico e também o comportamento das variâncias dos estimadores. A presença de censuras na amostra inflacionou as variâncias dos estimadores de máxima verossimilhança além de produzir estimativas viciadas para um dos parâmetros da regressão, sendo que o vício do estimador foi corrigido por meio de um processo "bootstrap". Na modelagem sem termo de fragilidade, os resultados das análises das probabilidades de cobertura empírica dos intervalos de confiança assintóticos mostraram uma boa aproximação com os valores esperados, mas com certos cuidados a serem tomados, especialmente nos procedimentos baseados na simetria das distribuições empíricas. A inclusão de um termo de fragilidade na modelagem, por sua vez, causou uma perturbação na estimação máxima verossimilhança com um aumento nas variâncias dos estimadores diretamente associados à variabilidade do termo de fragilidade. Além disso, as coberturas empíricas dos intervalos de confiança assintóticos foram, na grande maioria superestimadas, com resultados satisfatórios apenas para o parâmetro de forma da distribuição Weibull. / Renewal Processes are a special case of point processes involving recurrent events in which a unit, after a failure, is restored to the like new condition. Due to that property the times between occurrences for a renewal process are independent and its intensity function is given by the hazard function. Random factors not observed, that afects the recurrence times of the units, can be explained by a frailty term added in the model. In this work a regression model is presented for a renewal process with Weibull distribution for the times between occurrences. The modeling considers censored times and a frailty variable to explain the relationship among the recurrence times of a unit. The methodology was developed for the situation where several units are submitted by recurrent events. The empirical probabilities of coverage of the asymptotic normal confidence interval and the behavior of the variances of the estimators were analyzed in the simulations performed. The presence of censures in the sample inflated the variances of the maximum likelihood estimators besides to produce biased estimates for the regression parameters. The bias of the estimator was corrected by "bootstrap" procedure. The analysis of the probability of empirical coverage of the asymptotic confidence intervals, without frailty, presented a good approximation to the nominal values, but some observations about procedures have to be made on the symmetry of the empirical distributions. The frailty term incorporated at the modeling disturbed the maximum likelihood estimation increasing estimators' variability, directly associated to the variance of the fragility term. In the most of the cases, the empirical coverages of the asymptotic confidence intervals were overestimated, with satisfactory results just for the shape parameter of the Weibull distribution.

A hipogamaglobulinemia é uma alteração da imunidade humoral caracterizada por baixos níveis séricos de anticorpos podendo ter causas primárias e secundárias. Estes pacientes apresentam uma susceptibilidade a infecções bacterianas de repetição ou crônicas, principalmente do trato respiratório. Além disso, há alta prevalência de doenças gastrointestinais infecciosas e inflamatórias, hepatite C, doenças auto-imunes, doenças linfoproliferativas e granulomatosas. Ainda que a doença seja conhecida desde 1954 há poucos trabalhos na literatura sobre manifestações bucais nestes pacientes. Alguns estudos sugerem uma maior prevalência de lesões liquenóides, doença periodontal, candidíase pseudomembranosa, úlcera aftosa recorrente e hipoplasia de esmalte. Desta forma, o objetivo deste trabalho foi avaliar a prevalência das manifestações e alterações bucais, e caracterizar a saúde bucal de pacientes com hipogamaglobulinemias e correlacioná-las com o estado imunológico do paciente, comparativamente a um grupo de pacientes saudáveis. Para tanto avaliamos 100 pacientes com hipogamaglobulinemias atendidos no Ambulatório de Imunologia e Alergia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo e 93 pacientes normorreativos da Clínica Odontológica da Faculdade de Odontologia da Universidade de São Paulo, sendo realizado exame clínico bucal, anamnese e compilação de exames laboratoriais recentes. Do total de pacientes com hipogamaglobulinemias, 59 pacientes apresentaram alguma alteração bucal, sendo as mais frequentes lesões de cárie (21), hipoplasia de esmalte (21), gengivite (18), periodontite (8), boca seca (6), língua geográfica (5) e úlcera aftosa recorrente (2). Vinte e sete pacientes apresentaram queixas de úlcera aftosa recorrente com frequência. Dos 93 pacientes do grupo controle, 84 (90,3%) apresentaram alguma alteração bucal, sendo as mais frequentes lesões de cárie (66), gengivite (31), periodontite (44) e candidíase (3). Dezoito pacientes apresentaram queixas de úlcera aftosa recorrente com freqüência. Concluímos que os pacientes com hipogamaglobulinemias, apesar de apresentarem diminuição das imunoglobulinas do sangue, e alguns pacientes apresentarem uma diminuição de células da imunidade celular, não se encontrou relação positiva entre a incidência de cárie e IgA, doença periodontal e IgA e doença periodontal e CD4. / The hypogammaglobulinemia is an alteration in humoral immunity characterized by low levels of antibodies may have primary and secondary causes. These patients have a susceptibility to recurrent bacterial infections or chronic diseases, mainly respiratory tract. Moreover, there is a high prevalence of infectious and inflammatory gastrointestinal diseases, hepatitis C, autoimmune diseases, lymphoproliferative diseases and granulomatous disease. Although the disease is known since 1954 there are few available studies on oral manifestations in these patients. Some studies suggest a higher prevalence of lichenoid lesions, periodontal disease, pseudomembranous candidiasis, recurrent aphthous ulcer and enamel hypoplasia. Thus, the objective was to assess the prevalence of manifestations diseases and to characterize the oral health of patients with hypogammaglobulinemia and correlate with the immune status, compared with healthy patients. For that evaluated 100 patients with hypogammaglobulinemia in the Outpatient Immunology and Allergy Hospital of the Faculty of Medicine, University of São Paulo and 93 healthy patients of School of Dentistry, University of São Paulo, and was conducted oral clinical examination, medical history and compilation of recent laboratory tests. Of all patients with hypogammaglobulinemia, 59 patients showed abnormalities of the mouth, with 21 patients exhibited caries, 21 enamel hypoplasia, 18 gingivitis, 8 periodontitis, 6 dry mouth, 5 geographic tongue and 2 recurrent aphthous ulcer. Twenty-seven patients complained of frequent recurrent aphthous ulcer. Of the 93 control group patients, 84 (90.3%) showed abnormalities, being the most frequent caries (66), gingivitis (31), periodontitis (44) and candidiasis (3). Eighteen patients complained of recurrent aphthous ulcers frequently. We conclude that patients with hypogammaglobulinemia, despite showing decreased blood immunoglobulins, and some patients had a decrease of cells in cellular immunity, we did not find a positive relationship between the incidence of caries and IgA, IgA and periodontal disease and periodontal disease and CD4.

A intervenção cirúrgica sobre a glândula tireóide pode apresentar diversas complicações, sendo uma das mais temidas é a lesão dos nervos laríngeos recorrentes que leva a paresia ou paralisia da prega vocal em até 15% dos pacientes conforme registra a literatura. No entanto, muitas vezes os índices de lesão do nervo são subestimados, pois muitas vezes apenas pacientes com sintomas importantes são investigados, muitas vezes, no entanto, a preocupação com a lesão do nervo é crucial durante o ato cirúrgico, especialmente em dissecções bilaterais do nervo. Apesar dos enormes avanços tecnológicos dos últimos tempos, esta complicação apenas diminui, não desapareceu. Diversas técnicas de diagnóstico intra-operatório de viabilidade do nervo foram desenvolvidas nas últimas décadas, porém muitas delas de difícil execução prática, outras apresentam altos índices de complicações e outras ainda tem pouca especificidade no diagnóstico da lesão do nervo laríngeo recorrente. Uma das técnicas de maior aceitação é a monitorização intra-operatória não invasiva dos nervos laríngeos recorrentes através da utilização do eletrodo de superfície acoplado à cânula endotraqueal. Esta técnica apresenta diversas vantagens pois não estende o tempo cirúrgico, não há necessidade de modificação da técnica operatória ou anestésica e é de fácil utilização e assimilação pela equipe médica. No entanto muito se discute hoje na literatura sobre os reais benefícios desta tecnologia e qual o impacto na diminuição da lesão pósoperatória do nervo laríngeo recorrente. Assim foi estudado através de um estudo duplo-cego e randomizado a evolução de pacientes submetidos à tireoidectomia com e sem a utilização da monitorização intra-operatória do nervo laríngeo recorrente. Para tal análise avaliamos e comparamos os resultados pré e pós operatório dos parâmetros de mobilidade das pregas vocais (através da laringoscopia direta) e função (através da análise vocal auditiva e acústica), além do tempo gasto na identificação do nervo laríngeo recorrente no intra-operatório. Os pacientes foram operados consecutivamente pelo mesmo cirurgião e submetidos à mesma técnica operatória e anestésica, sendo a utilização do equipamento definida por sorteio no momento da indução anestésica. Os resultados desta comparação não mostraram diferenças estatisticamente significativas na comparação tanto dos achados de laringoscopia, quanto na análise vocal pelos parâmetros auditivos e acústicos, tão pouco houve diferença no tempo gasto na dissecção do nervo. A maior vantagem apresentada pela utilização do sistema de monitoramento intra-operatório foi conseguir predizer a perda de função do nervo laríngeo recorrente já no intra-operatório. Desta forma, o estudo foi capaz de afirmar que a utilização da monitorização intra-operatória não invasiva do nervo laríngeo recorrente não traz melhora dos índices de lesão do nervo, nem diminuição do tempo gasto na sua identificação, sua maior vantagem é identificar possíveis injúrias sobre o nervo já no intra-operatório / The surgery of the thyroid gland could present several complications, one of the most feared is the recurrent laryngeal nerve injury leading to vocal fold paresy or paralysis up to 15% of patients according to literature. However, many times the rate of nerve injury are underestimated because frequently only patients with significant symptoms are investigated, often however the concern about the nerve injury is crucial during surgery, especially in bilateral dissections of the nerve. Despite enormous technological advances of recent times, this kind of complication only diminishes, not disappeared. Several techniques of intraoperative nerve viability have been developed in recent decades, but many of them are difficult to implement, others have high rates of complications and still others have little specificity in the diagnosis of recurrent laryngeal nerve injury. One of the most accepted techniques for nerve evaluation is the noninvasive intraoperative monitoring by using surface electrodes attached to the endotracheal tube. This approach has several advantages because it no extends the operating time, no need modification of surgical or anesthetic technique and is easy to use and be assimilated by the surgical team. However there is no consensus in the literature about the real benefits of this technology and what is its impact on the reduction of postoperative injury of the recurrent laryngeal nerve. It was evaluated by a double-blind, randomized study of patients underwent thyroidectomies with and without the use of intraoperative monitoring sistem of recurrent laryngeal nerve. For this analysis we evaluated and compared the results of preoperative and postoperative parameters of vocal fold mobility (by direct laryngoscopy) and function (through vocal and and acoustic analysis), the time spent in identifying the recurrent laryngeal nerve during surgery was also compared. The patients were operated by the same surgeon and by the same surgical and anesthesia techniques, and the use of the equipment was determined by drawing. The results of this comparison showed no statistically significant differences when comparing the findings of laryngoscopy and the vocal and acoustic parameters also there was no difference in time spent in the dissection of the nerve. The major advantage presented by the use of intraoperative monitoring system was the capacity to predict the loss of function of the recurrent laryngeal nerve during surgery. Thus the study was able to assert that the use of the noninvasive intraoperative monitoring system does not improve the rates of nerve injury neither less time was spent on its identification, the major advantage is to identify possible injuries of the nerve intraoperatively

Major advances in machine learning have made image recognition applications, with Artificial Neural Network, blossom over the recent years. The aim of this thesis was to find a solution to recognize digits from a number sequence on an ID tag, used to identify farm animals, with the help of image recognition. A Recurrent Convolutional Neural Network solution called PPNet was proposed and tested on a data set called Animal Identification Tags. A transfer learning method was also used to test if it could help PPNet generalize and better recognize digits. PPNet was then compared against Microsoft Azures own image recognition API, to determine how PPNet compares to a general solution. PPNet, while not performing as good, still managed to achieve competitive results to the Azure API.