Made available in DSpace on 2015-04-22T22:12:38Z (GMT). No. of bitstreams: 1 Marcos Melo Correa.pdf: 3085652 bytes, checksum: ad02fd98038c54ac33211ab40d13e32c (MD5) Previous issue date: 2013-03-23 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The internal taxonomical organization of the Chrysobalanaceae is problematical and studies are needed with large numbers of taxa. This work is an anatomical and morphological description of 20 species of Chrysobalanaceae from the genera Couepia, Licania and Parinari occurring in the Adolpho Ducke Forest Reserve, Manaus AM. Morphological observations were made using a stereomicroscope. In addition, leaves were cleared with sodium hydroxide to see details of venation pattern. We characterized the epidermis frontal view using the method of dissociation with Franklin solution and paradermal cuts. The petiole, midrib and mesophyll were analyzed by cross sections from the middle third. The species analyzed herein have the basic morphological pattern described for the family, with simple, alternate, distichous, petiolate leaves with stipules usually present in younger branches. Macroscopic characters such as the shape of the blade, stipule type and the presence or position of glands vary between species. The most recurrent venation pattern among the species studied is the eucamptodromous with the occurrence in some cases of mixed eucamptodromous / broquidodromous venation. The petiole vascularization in all species is formed by continuous or discontinuous rings, or two or three arcs. The vascular bundles of the midrib are organized into arcs formed by two or three collateral bundles or forming a closed ring which may present an inner phloematic arc. The predominant type of anticlinal contour in the upper surface of the leaves is straight, with varying forms in the lower surface. The species have paracytic stomata, some occurring in stomatal crypts. The mesophyll of all species is dorsiventral, with both sides lined by a thick cuticle in several species. The epidermal cells on the adaxial surface are tabular, cubic or rectangular in shape. Palisade tissue occurs in one to three layers of elongated cells and spongy parenchyma compression varies according to the species. Sheath extensions and columnar sclereids occur in various species. An identification key was developed, as well as standardized descriptions using morphological and anatomical features. The following anatomical characters contributed more to the diagnosis, showing greater variation per feature, and were of most use in the key: position of glands, position of stomata in the epidermal line, shape of the stipules, number of layers of the upper epidermis, number of accessory vascular bundles in the petiole and development of areoles. The character set is effective in differentiating between species. / Chrysobalanaceae apresenta organização taxonômica interna problemática e estudos são necessários contendo grande número de táxons. Este trabalho apresenta a descrição morfológica e anatômica de 20 espécies de Chrysobalanaceae dos gêneros Couepia, Licania e Parinari ocorrentes na Reserva Florestal Adolpho Ducke, Manaus AM. A caracterização morfológica foi realizada com observação em estereomicroscópio, além de diafanização com hidróxido de sódio para detalhamento do padrão de venação. A epiderme foi caracterizada em vista frontal com uso do método de dissociação com solução de Franklin e cortes paradérmicos. O pecíolo, a nervura central e o mesofilo foram analisados a partir de cortes transversais no terço médio. As espécies possuem o padrão morfológico básico descrito para a família, com folhas simples, alternas, dísticas, pecioladas, com estípulas presentes geralmente nos ramos mais jovens. Caracteres macroscópicos como o formato do limbo, tipo de estípulas e a presença ou posição das glândulas variam entre espécies. O padrão de venação mais recorrente entre as espécies é o eucamptódromo, com a ocorrência em alguns casos de venação mista eucamptódroma/broquidódroma. A vascularização do pecíolo em todas as espécies é formada por anéis contínuos ou descontínuos, ou ainda arcos variando de dois a três. O feixe vascular da nervura central organiza-se em arcos formados por feixes colaterais que estão dispostos em número de dois ou três, ou formando um anel fechado no qual pode estar presente um arco floemático. O tipo de contorno anticlinal predominante na face adaxial das folhas é reto, com formas variáveis na face abaxial. Os estômatos são paracíticos, alguns ocorrendo em criptas estomáticas. O mesofilo de todas as espécies é dorsiventral, com ambas as faces revestidas por cutícula espessa. As células epidérmicas da face adaxial apresentam formato tabular, cúbico ou retangular. Ocorrem no parênquima paliçádico de uma a três camadas de células alongadas e o parênquima lacunoso apresenta compactação variável de acordo com a espécie. Extensões de bainha e esclereides colunares são de ocorrência comum. As espécies apresentam características escleromórficas, como a cutícula espessa, extensões de bainhas de feixes vasculares e criptas estomáticas. Esses caracteres indicam adaptação ao ambiente florestal de solo pobre, bem como aos fatores que interferem na utilização adequada dos recursos hídricos. Estômatos acima da linha epidérmica foram a única característica que ocorreu exclusivamente em espécies de Licania. Foi elaborada uma chave de identificação, assim como descrições padronizadas utilizando os caracteres morfoanatômicos. Os caracteres anatômicos deram maior contribuição para a diagnose, pois apresentaram maior variação entre as espécies, sendo os principais utilizados na chave: posição das glândulas, posição dos estômatos na linha epidérmica, forma das estípulas, número de camadas da epiderme adaxial, número de feixes acessórios no pecíolo e desenvolvimento das aréolas. O conjunto de caracteres é eficaz na diferenciação entre espécies.

O percurso histórico de derivações sufixais é muito pouco estudado, pois é lugar-comum concentrarem a análise de formação de palavras sob a ótica sincrônica. O presente trabalho constitui-se de um estudo calcado em diacronia sobre as ocorrências dos sufixos -ança/-ença, -ância/-ência, em suas funções transcategorial e semântica. Em manuais de gramática normativa, afirma-se, comumente, que esses sufixos se prestam apenas a transpor a classe gramatical de uma palavra, de verbo a substantivo abstrato, e acrescentam à base um significado superficial. Os modelos gerativos de estudo morfológico, por sua vez, embora reconheçam a polissemia dos sufixos, instituem regras de derivação sufixal que não abrangem a total possibilidade formativa, encontrada no processo histórico dos sufixos abordados. O objetivo de nossa pesquisa tratava-se de precisar dados etimológicos encontrados no Dicionário Houaiss, para com isso investigar os valores semânticos variáveis no percurso diacrônico dos sufixos, avaliar a tendência formativa transcategorial, desde o latim clássico, e verificar a relação que os substantivos derivados estabelecem com seus verbos e adjetivos cognatos. Com base em um corpus de 250 palavras usuais formadas por esses sufixos, investigamos a etimologia dos vocábulos, utlizando-se de dicionários de latim, clássico e medieval, inglês, francês, espanhol e italiano, confrontando os dados encontrados com aqueles fornecidos pelo Dicionário Houaiss. Descrevemos os valores semânticos dos sufixos em forma de paráfrases, discernindo os prototípicos daqueles advindos de empréstimos ou por extensão de sentido. Averiguamos a cognação desses substantivos derivados entre adjetivos em -nte e verbos, no português atual. Dessa forma, pudemos concluir que esses sufixos se revestem de variáveis valores semânticos, prototípicos e adquiridos em seu percurso diacrônico; prestam-se à criação de substantivos majoritariamente abstratos, pois há ocorrências de substantivos concretos, e possuem a tendência de formar derivados a partir de bases adjetivais e verbais, ainda que, ao longo da história, desde o latim, tenham existido formações com outras categorias. / The historical trajectory of suffixal derivations is too little studied, since it is a commonplace to concentrate the analysis of words formation under a synchronical point of view. The present work deals with a study set in the diachronical perspective of the suffixal occurrences of Portuguese suffixes -ança/-ença, -ância/-ência, in their transcategorical and semantical functions. In normative grammar manuals, it is used to affirm that these suffixes are useful in order to cross over the grammatical class of a word, from a verb to an abstract noun, and to add it on the basis of a superficial meaning. The generative models of Morphology, in their turn, recognize even though the polysemy of the suffixes and establish suffixal derivation rules that do not embrace all formative possibilities, found in the historical process of the broached suffixes. The purpose of this research was specify etymological data found in the Dicionário Houaiss, to, hereby, investigate the changeable semantic values in their suffixal diachronic trajectory, evaluate their transcategorical formative tendency, since the Classic Latin, and verify the relation that the derivative nouns establish with their verbs and cognate adjectives. Based on a corpus of 250 usual words formed by these suffixes, we investigate the etymology of the terms, consulting dictionaries of Classic and Medieval Latin, English, French, Spanish and Italian, confronting the found data with those supplied by the Dicionário Houaiss. We describe the semantical values of the suffixes in the form of paraphrases, discriminating the prototypical one from those ocurred by loans or by meaning extensions. We inquire the cognation of these derivative nouns among adjectives in -nte and verbs, in the current Portuguese. This way, we could conclude that these suffixes resemble themselves with changeable semantical values, prototypical and acquired in their diachronical trajectory; they are useful to the creation of nouns mainly the abstract ones, because there are occurrences of concrete nouns, and have the tendency to form derivatives from adjectival and verbal bases, although, alongside the history, since the Latin, formations with other categories have also existed.

Thesis (M. A. (African Languages)) -- University of Limpopo, 2004 / Refer to document

In dieser Dissertation schlage ich eine Synthese (Distributed Optimality, DO) von Optimalitätstheorie und einem derivationellen, morphologischem Asatz, Distributed Morphology (DM; Halle & Marantz, 1993) vor. Durch die Integration von OT in DM wird es möglich, Phänomene, die in DM durch sprachspezifische Regeln oder Merkmale von lexikalischen Einträge erfasst werden, auf die Interaktion von verletzbaren, universellen Constraints zurückzuführen. Andererseits leistet auch DM zwei substantielle Beiträge zu DO, Lokalität und Impoverishment. Lokalität erlaubt eine formal einfache Interpretation von DO, während sich Impoverishment als unverzichtbar erweist, um Kongruenz-Morphologie adäquat zu beschreiben. Die empirische Grundlage der Arbeit sind die komplexen Kongruenzsysteme von genetisch unterschiedlichen Sprachen.<br /> Der theoretische Schwerpunkt liegt in zwei Bereichen: Erstens, sogenannte Direkt/Invers-Markierung, für die gezeigt wird, dass eine Behandlung durch Constraints über Merkmalsrealisierung am angemessensten ist. Zweitens, die Effekte von Abfolge-Constraints, die den Satus von Affixen als Präfixe und Suffixe sowie ihre relative Reihenfolge regeln. Eine konkrete Typologie für die Abfolge von Kongruenz-Affixen auf der Basis von OT-Constraints wird vorgeschlagen. / In this thesis I propose a synthesis (Distributed Optimality, DO) between Optimality Theory (OT, Prince & Smolensky, 1993) and a morphological framework in a genuine derivational tradition, namely Distributed Morphology (DM) as developed by Halle & Marantz (1993). By carrying over the apparatus of OT to DM, phenomena which are captured in DM by language-specific rules or features of lexical entries, are given a more principled account in the terms of ranked universal constraints. On the other hand, also the DM part makes two contributions, namely strong locality and impoverishment. The first gives rise to a simple formal interpretation of DO, while the latter is shown to be indispensable in any theoretically satisfying account of agreement morphology. The empirical basis of the work is given by the complex agreement morphology of genetically different languages. <br /> Theoretical focus is mainly on two areas: First, so-called direction marking which is shown to be preferably treated in terms of constraints on feature realization. Second, the effects of precedence constraints which are claimed to regulate the status of agreement affixes as prefixes or suffixes and their respective order. A universal typology for the order of agreement categories by means of OT-constraints is proposed.

Muscles control body posture and movement by extrafusal and intrafusal (muscle spindle) fibres. The purpose of this thesis was to provide insight into the muscular basis for human jaw function at young age. Extrafusal and intrafusal fibres in the young masseter, and for comparison young biceps, were examined for composition of fibre types and myosin heavy chain (MyHC) isoforms by means of morphological, enzyme-histochemical, biochemical and immuno-histochemical techniques. For evaluation of plasticity during life span the data for young muscles were compared with previous reported data for adult and elderly muscles. The results showed significant differences in extrafusal fibre types and MyHC expression between young masseter and young biceps and between young masseter and masseter in adults and elderly. Compared with young biceps, young masseter was more intricate in composition of extrafusal MyHC expression. Muscle spindles were larger and more frequent in the masseter than in the biceps. Masseter and biceps muscle spindles showed fundamental similarities but also marked differences in MyHC expression. The results suggest that the young masseter is specialized in fibre types already at young age and shows a unique fibre type growth pattern. Whereas masseter extrafusal fibres display marked plasticity in fibre types and MyHC isoforms during life span muscle spindles/intrafusal fibres are morphologically mature already at young age and precede extrafusal fibres in growth and maturation. Results showed similarities in intrafusal MyHC expression between young masseter and biceps, but also differences implying muscle specific proprioceptive control. Differences in fibre types and MyHC expression between young masseter and young biceps extrafusal fibres are proposed to reflect diverse evolutionary and developmental origins and accord with the masseter and biceps being separate allotypes of muscle.

The objective of this work is to investigate the elastic modulus of gastrula-stage avian embryos and the effect of substrate stiffness on presumptive precardiac cell fate. Our overall hypothesis is that the mechanical microenvironment, specifically, tissue modulus and substrate stiffness, influences gastrulation and cardiac induction. Large-scale morphogenetic movements during early embryo development are driven by complex changes in biochemical and biophysical factors. Current models for amniote primitive streak morphogenesis and gastrulation take into account numerous genetic pathways but largely ignore the role of mechanical forces. Here, we used atomic force microscopy (AFM) to obtain for the first time precise biomechanical properties of the early avian embryo. Our data reveal that the primitive streak is significantly stiffer than neighboring regions of the epiblast, and that it is stiffer than the pre-primitive streak epiblast. To test our hypothesis that these changes in mechanical properties are due to a localized increase of actomyosin contractility, we inhibited actomyosin contractility via the Rho kinase (ROCK) pathway using the small-molecule inhibitor Y-27632. Our results using several different assays show the following: 1) primitive streak formation was blocked; 2) the time-dependent increase in primitive streak stiffness was abolished; and 3) convergence of epiblast cells to the midline was inhibited. Taken together, our data suggest that actomyosin contractility is necessary for primitive streak morphogenesis, and specifically, ROCK plays a critical role. To better understand the underlying mechanisms of this fundamental process, future models should account for the findings presented in this study. As presumptive cardiac cells traverse the course of differentiation into cardiac myocytes during cardiogenesis, the sequence, magnitude, and spatiotemporal map of biomechanical and biochemical signals has not been fully explored. There have been many studies detailing the induction of cardiogenesis on a variety of substrates and extracellular matrix (ECM) proteins, but none have completed a rigorous study of the effects of substrate stiffness on the induction of precardiac cells prior to the onset of cardiac gene expression (smooth muscle alpha actin [SMAA] at stage 5.) We investigate the effects of the mechanical environment on precardiac cell behaviors in an in vitro setting to elucidate the effect of substrate stiffness and inducing factors on precardiac tissue and the potential connection between them. The cells in the anterior portion of the primitive streak are fated to form the heart, and we show differing levels of SMAA expression on substrates of differing moduli, which suggests that substrate stiffness may play a role in cardiac differentiation. We cannot determine the physical mechanisms during morphogenesis without understanding the response of precardiac cells to changes in their mechanical environment.

The brain has been one of the central foci in studies of vertebrate evolution. Work in East African cichlids and other emerging fish models like the Mexican cavefish (Astyanax mexicanus) offer new insight on the role of patterning on brain evolution. These fish can be grouped into two major categories according to habitat; for cichlids it is rock-dwelling (known locally as mbuna) and sand-dwelling (non-mbuna) lineage. The brain development of mbuna versus non-mbuna is defined by changes in gene deployment working along the dorsal/ventral (DV) and anterior/posterior (AP) neuraxes, respectively. Comparison of disparate fish ecotypes offer a new perspective of the role of patterning on brain evolution; through the slight and early modification of signal pathways working across 3-D axes, and a subsequent magnifying effect across ontogeny, evolution can generate widespread changes in the brain. To illustrate this patterning model of brain evolution, two comparative studies were done between mbuna and non-mbuna, examining the action of gene pathways that work to pattern the cichlid forebrain. The first study found that non-mbuna cichlids have a more rapid AP expansion of a gene pathway (Wingless) into the presumptive midbrain and diencephalon versus mbuna. These forebrain structures are involved in sight processing and could be of ecological benefit to vision-focused non-mbuna. The second study described a difference within the developing telencephalon. The embryonic telencephalon is split into the pallium, which processes visual signals, and the subpallium, which develops into the olfactory bulbs. Mbuna possess a larger subpallium relative to non-mbuna, which have a larger pallium. This was correlated to a more rapid expansion of another gene pathway (Hedgehog) along the DV axis. The difference in size of the pallial vs. subpallialial comparments between cichlids can be correlated to expanded olfaction in mbuna and vision in non-mbuna adult brains. Overall, East African cichlids are an excellent system to investigate the role of patterning on brain evolution because they allow for the comparison of the earliest patterning events in brain ontogeny between distinct ecotypes. These fish systems link study in brain development to the brain morphology comparisons employed in classic studies of brain evolution.

This thesis is devoted to the investigation of two morphological classes in Tocharian and their Indo-European prehistory and affiliation: 1) the continuants of Proto-Indo-European (PIE) thematic ("class I") adjectives, and 2) a class of agent formations related to them. / Linguistics

This dissertation examines the dynamics of sediment transport and channel morphology in the lower Mississippi River. The area of research includes the portion of the river where reach-averaged downstream flow velocity responds to the boundary condition imposed by the relatively uniform water-surface elevation of the receiving basin. Observational studies provided data that are used to identify channel-bed sediment composition, and measure bed-material sediment flux and the properties of the fluid-flow field over a variety of water-discharge conditions. The analyses demonstrate that a significant portion of the channel bed of the final 165 kilometers of the Mississippi River consists of exposed and eroding underlying relict sedimentary strata that qualify as surrogate bedrock. The exposed bedrock is confined to the channel thalweg, particularly in river-bend segments, and actively mobile bed-material sediments are positioned on subaqueous bars fixed by river planform. The analyses for sediment flux provides insight to the nature of sediment transport: during low- and moderate-water discharge, bed-material movement occurs primarily as minimal bedform flux, and so bed materials are not transferred between alluvial bars. During high-water discharge, bed-material transport increases one-hundred fold, and sands move as a part of both suspended and bedform transport. Physical models are used to show that skin-friction shear stress increases by a factor of ten for the measured water-discharge range. This change is not possible given conditions of uniform water flow, and therefore non-uniform flow in response to the Mississippi River approaching its outlet has a significant impact on the timing and magnitude of sediment flux through the lower river. In order to estimate the dynamics of bed material movement from the uniform to non-uniform segment of the river (lower 800 km), data for channel morphology are used to construct a model that predicts spatial changes in water-flow velocity and bed-material flux over a range of water-discharge conditions. The model demonstrates that non-uniform flow tends to produce a region of net channel-bed aggradation between 200-700 kilometers above the outlet, and a region of channel-bed degradation for the final 200. The implication for these results for the spatial variability of channel morphology and kinematics is explored. / text

published_or_final_version / abstract / toc / Linguistics / Master / Master of Philosophy