This paper will be devoted to an exposition of some of the relationships existing between a field and certain of its extension fields. In particular, it will be shown that many fields may be characterized rather simply in terms of their subfields which, in turn, may be directly correlated with the subgroups of a finite group of automorphisms of the given field.

Temporal context memory is a type of episodic memory that refers to memory for the timing of events. Temporal context includes environmental cues that provide information about the time point at which an event happened. The purpose of the present studies is to investigate the brain mechanisms underlying temporal context processing by using both fMRI and ERP techniques. The fMRI study investigated whether hippocampal representations in CA1 and DG/CA3 subfields were sensitive to the flow of physical time, and if so, whether the number of events that occur during a time period influences the temporal representation of a target event. Results showed that both CA1 and DG/CA3 were sensitive to the flow of physical time, which was indicated by higher representational similarity between two pictures that occurred closer in time than those that occurred more distant in time. However, the variety of preceding events did not influence temporal representation, which was demonstrated by the lack of a significant representational similarity difference between two pictures that were interleaved with variable events as opposed to similar events. The ERP study compared the ERP correlates of temporal to spatial context. Results showed that temporal and spatial contexts had overlapping ERP effects except that the ERP effects of temporal context were more frontally distributed than spatial context. Both the fMRI and ERP studies indicate that temporal context is associated with similar neural correlates to other types of context in episodic memory. / Ph. D. / Episodic memory is memory for where and when an event happened. The ability to memorize the timing of events relies on one type of episodic memory: temporal context memory. Temporal context includes environmental cues that provide information about the time point at which an event happened. The purpose of the present studies was to investigate the brain mechanisms underlying temporal context processing by using both functional magnetic resonance imaging (fMRI) and event and event-related potential (ERP) techniques. The fMRI study focused on hippocampus, one of the key brain regions process non-temporal contexts (i.e. spatial context, which refers to where an event happened), and investigated which subfields (CA1 and DG/CA3) in the hippocampus were sensitive to the flow of physical time. And the second purpose of the fMRI study was to examine whether the variety of events that occur during a time period influences the temporal representation. Results showed that both CA1 and DG/CA3 were sensitive to the flow of physical time. However, the variety of events did not influence temporal representation. Since CA1 and DG/CA3 are also critical for non-temporal context processing, these results indicate that temporal context has same neural mechanisms as non-temporal contexts. The ERP study investigated the brain activity as a whole and directly compared the ERP correlates of temporal to non-temporal context. Results showed that temporal and nontemporal contexts had overlapping ERP correlates except that the ERP effects of temporal context were more frontally brain region distributed than spatial context. Therefore, both the fMRI and ERP studies indicate that temporal context is associated with similar neural correlates to other types of context in episodic memory.

The research productivity fellowship from CNPq is one of the most coveted scientific grants in Brazil. Although, it positively impacts the researcher's career and institution, the profile of this researchers is still unknown. This thesis presents the main bibliometric indicators related to the scientific judgment of PQ fellowships from the Coordination of the Research Program on Chemical Sciences and Geosciences (COCQG-CNPq). 1062 researchers from Chemistry and Geosciences had their profiles analyzed. The results from Chemistry and Geosciences show differences in the profiles of researchers from different subfields and specialties in the same main area, example H index in the specialties of chemistry and number of articles published in specialties of Geosciences. This results suggest that the bibliometric indicators analyzed in this study should be used with caution in the process of granting PQ fellowships since there are area, sub area and specialties specificities. This thesis to contribute to the scientific evaluation of researchers from exact sciences who long to become PQ fellows or to continue to be one of them. The study might also contribute to the improvement of the criteria established by the CNPq's Assessor Committees. / A bolsa de Produtividade em Pesquisa (PQ) é uma das modalidades de bolsa do CNPq mais cobiçadas pelos pesquisadores, pois o título confere um impacto positivo à vida acadêmica do pesquisador e da instituição a que está vinculado. Apesar do grande interesse nesta modalidade de bolsa, pouco se sabe sobre o perfil produtivo destes bolsistas PQ. O projeto de pesquisa apresentado nesta tese envolve os principais indicadores objetivos e quantitativos de produtividade científica relacionados nos critérios de julgamento das bolsas PQ das áreas da Coordenação do Programa de Pesquisa em Ciências Químicas e Geociências. Este universo se refere a 1062 bolsistas PQ das áreas de Química e Geociências. Os resultados obtidos nas áreas de Química e Geociências apresentam diferenças nos perfis de produtividade científica dos bolsistas PQ dentro das diferentes subáreas e especialidades das áreas estudadas, como o índice H nas especialidades da Química e o número de artigos publicados nas especialidades das Geociências. Estes resultados demonstram que os indicadores bibliométricos devem ser analisados com cautela nos processos de concessão de bolsas devido às especificidades das áreas, subáreas e especialidades. Esta tese se propõe a contribuir na avaliação da produtividade científica dos pesquisadores das áreas de Química e Geociências que almejam a ser contemplados com a bolsa PQ ou que pretendem continuar no sistema de bolsas do CNPq e também contribuir no aprimoramento dos critérios de julgamentos utilizados pelos Comitês de Assessoramento do CNPq.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-12-10T13:29:38Z No. of bitstreams: 1 Dissertação - Adriano Honorato Braga - 2013.pdf: 1269065 bytes, checksum: 31a4446602e6fc177149b700de63b216 (MD5) / Rejected by Erika Demachki (erikademachki@gmail.com), reason: on 2014-12-10T13:30:49Z (GMT) / Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-12-15T16:01:05Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Adriano Honorato Braga - 2013.pdf: 1269065 bytes, checksum: 31a4446602e6fc177149b700de63b216 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2014-12-15T16:30:34Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Adriano Honorato Braga - 2013.pdf: 1269065 bytes, checksum: 31a4446602e6fc177149b700de63b216 (MD5) / Made available in DSpace on 2014-12-15T16:30:34Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Adriano Honorato Braga - 2013.pdf: 1269065 bytes, checksum: 31a4446602e6fc177149b700de63b216 (MD5) Previous issue date: 2013-10-15 / Scientific studies about bibliographic productions in specific areas of science are becoming common, mainly in the last decade. Such investigations usually make use of bibliometric indices to evaluate relevance of the actors that take part in scientific production process, such as: authors, institutions, venues, and subfields of the scientific area being considered. Many studies have investigated the scientific production in computer science under different views. In this work, its presented an analysis about the production of scientific article in computer science and an analysis of citations among subfields, derived from article citation network. The work present novelty not only because it considers many common sense fields in computer science, but also because it presents citation related measures chronologically. The following bibliometric measures were used: number of publications in each subfield, number of citations received by a subfield, Impact Factor, PageRank, and a measure of diversity of subfields that cite a given subfield. Most of those metrics were proposed to study articles, web pages or scientific journals and they had to be adapted to be applied to the subfield analysis. This work has derived many interesting information to computer science community. It presents an historical evolution of the computer science subfields, showing how interest in publishing in subfields and how citations among subfields have evolved during the years. Some trends are revealed, some patterns are recognized to be stable along the time and some subfields are becoming less attractive than others. / Trabalhos que analisam as produções bibliográficas nos mais variados ramos da ciência têm se tornados comuns, principalmente na última década. Tais análises geralmente utilizam-se de índices ou medidas propostas para avaliar relevância de diferentes atores envolvidos no processo de produção científica, tais como: autores, instituições, veículos de publicação e subáreas do ramo da ciência considerado. Vários trabalhos têm investigado a produção científica em ciência da computação sob diversos aspectos. Neste trabalho é apresentado um estudo sobre a produção de artigos científicos nas subáreas da computação, bem como uma análise das citações entre as subáreas, derivadas das citações existentes nos artigos pertencentes a cada subárea. Esse estudo apresenta novidade não apenas pela abrangência das subáreas da computação analisadas, mas principalmente por levar em consideração o aspecto cronológico (ano de publicação) do comportamento de cada subárea sob diferentes índices bibliométricos: quantidade de publicações, quantidades de citações recebidas, PageRank, Fator de impacto e um índice para aferir se uma determinada subárea é citada diversificadamente por várias áreas ou se as citações são feitas principalmente por determinado grupo de subáreas. Algumas dessas medidas utilizadas tradicionalmente para mensurar relevância de artigos ou veículos de publicação e tiveram que ser adaptadas para a análise de subáreas. O trabalho permitiu derivar informações interessantes para a comunidade científica em ciência da computação. É apresentada a evolução histórica das subáreas da computação, mostrando como o interesse por autores e como as citações entre subáreas têm mudado ao longo do tempo. Algumas tendências são reveladas, alguns padrões são reconhecidos como sendo cronologicamente estáveis e algumas subáreas têm se tornado menos atrativas do que outras.

Indiana University-Purdue University Indianapolis (IUPUI) / Object segmentation, quantification, and shape modeling are important areas inmedical image processing. By combining these techniques, researchers can find valuableways to extract and represent details on user-desired structures, which can functionas the base for subsequent analyses such as feature classification, regression, and prediction. This thesis presents a new framework for building a three-dimensional (3D) hippocampal atlas model with subfield information mapped onto its surface, with which hippocampal surface registration can be done, and the comparison and analysis can be facilitated and easily visualized. This framework combines three powerful tools for automatic subcortical segmentation and 3D surface modeling. Freesurfer and Functional magnetic resonance imaging of the brain's Integrated Registration and Segmentation Tool (FIRST) are employed for hippocampal segmentation and quantification, while SPherical HARMonics (SPHARM) is employed for parametric surface modeling. This pipeline is shown to be effective in creating a hippocampal surface atlas using the Alzheimer's Disease Neuroimaging Initiative Grand Opportunity and phase 2 (ADNI GO/2) dataset. Intra-class Correlation Coefficients (ICCs) are calculated for evaluating the reliability of the extracted hippocampal subfields. The complex folding anatomy of the hippocampus offers many analytical challenges, especially when informative hippocampal subfields are usually ignored in detailed morphometric studies. Thus, current research results are inadequate to accurately characterize hippocampal morphometry and effectively identify hippocampal structural changes related to different conditions. To address this challenge, one contribution of this study is to model the hippocampal surface using a parametric spherical harmonic model, which is a Fourier descriptor for general a 3D surface. The second contribution of this study is to extend hippocampal studies by incorporating valuable hippocampal subfield information. Based on the subfield distributions, a surface atlas is created for both left and right hippocampi. The third contribution is achieved by calculating Fourier coefficients in the parametric space. Based on the coefficient values and user-desired degrees, a pair of averaged hippocampal surface atlas models can be reconstructed. These contributions lay a solid foundation to facilitate a more accurate, subfield-guided morphometric analysis of the hippocampus and have the potential to reveal subtle hippocampal structural damage associated.