Thesis (M.S.P.H.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 45 pages. Includes bibliographical references.

This is a study on how Somali and Oromo refugees manage under uncertain circumstances in Eastleigh, Nairobi. Fleeing from war, persecution and violence, the refugees expected to find protection and a quick transfer to a third country, which was not the case. Instead, they ended up in being stuck, unsafe, and questioned. The refugees aimed for resettlement to a third country; a decision depending on approval from the hosting state, a receiving state, and UNHCR. This process normally included 8-10 years or more of waiting and a positive answer was not guaranteed. The spatial realities in displacement in Eastleigh included a status of illegitimacy, socioeconomic hardships, and unpredictability of an eventual resettlement in a third country. In the protracted waiting for resettlement they struggle to become part of the place but in the state of transit, and in an excluding context, they are in-between – in a liminal state in both space and time.

Os deslocamentos forçados de pessoas em que presente causa ambiental são resultado de uma função complexa que envolve diversos fatores caracterizantes da vulnerabilidade. Em razão do potencial de agravamento da degradação ambiental e da exacerbação de eventos climáticos extremos, as mudanças climáticas apresentam-se como fator multiplicador de ameaças para o movimento de pessoas. O princípio da responsabilidade primária do Estado para a proteção de direitos humanos parece afastar a responsabilidade dos demais Estados para o enfrentamento do problema, mas o fato é que, muitas vezes, o próprio Estado de origem não é capaz de garantir proteção efetiva às comunidades vulneráveis mais impactadas, além de fluxos externos de deslocamentos por causas ambientais já serem observados. Por outro lado, os sistemas internacionais de proteção da pessoa humana, por meio do direito humanitário, do direito dos refugiados e dos direitos humanos, não enfrentam adequadamente a totalidade do problema. O tema aponta um novo momento de reconstrução dos direitos humanos, de natureza global, que deve enfrentar violações de direitos humanos por agentes indefinidos, conectados, cumulativos e globais. A interdependência das causas requer a interdependência para a solução. O enfrentamento adequado do problema necessita de uma mudança de foco, da responsabilização por dano transfronteiriço para a responsabilidade em cooperar. / The forced displacement of people with environmental causes result of a complex function that involves several factors characterizing vulnerability. Because of the potential for worsening environmental degradation and the exacerbation of extreme weather events, climate change presents itself as threat multiplier factor for the movement of people. The principle of primary responsibility of the State for the protection of human rights seems to exclude the responsibility of other States to deal with the problem, but the fact is that, often, the State of origin is not able to guarantee effective protection to vulnerable communities, which are the most impacted, as well as external flows of people with environmental causes are already be observed. Moreover, the international systems of protection of the human being, through humanitarian law, refugee law and human rights, do not properly face the problem. The theme indicates a new moment for human rights, global in nature, that must face human rights violations by undefined, connected, cumulative and global agents. Interdependence of causes requires the interdependence for the solution. The adequate confrontation of the problem requires a change of focus, from the accountability for transboundary damage to the responsibility to cooperate.

Les vésicules extracellulaires (EVs) apparaissent depuis une dizaine d'années comme de nouveaux biomarqueurs à fort potentiel pour des applications de biopsie liquide. En effet, les EVs portent la signature de leurs cellules émettrices, par le transport de matériel génétique et protéique cellulaire, qui peut être exploité comme outil de diagnostic précoce. L’une des principales limitations actuelles à l'utilisation clinique des EVs est la difficulté à extraire ces nano-objets à partir de biofluides complexes et à standardiser les protocoles de préparation d'échantillon. En effet, de nouvelles technologies sont requises pour effectuer un isolement efficace, bas coût et rapide de sous-populations d'EVs, sans altérer leur intégrité et à partir de faibles volumes d'échantillon. La technique microfluidique de Déplacement Latéral Déterministe (DLD) apparaît comme une des technologies prometteuses pour atteindre ces performances grâce à une purification passive et sans marquage. Les dispositifs de DLD mettent en oeuvre un réseau de piliers générant un tri en taille des particules, et dont les paramètres géométriques permettent de contrôler précisément le diamètre de séparation. Parmi les nombreuses applications de cette technologie dans le secteur biomédical, aucune ne permet pour le moment de réaliser l'extraction complète d'EVs directement à partir du biofluide d'intérêt, sans étapes de purification intermédiaires par centrifugation par exemple. Dans cette perspective, nos développements technologiques ont pour but d'améliorer la fiablilité, l'efficacité et l'intégration des dispositifs de DLD. A partir d'études numériques et expérimentales, nous proposons ici de nouveaux modèles pour anticiper au mieux le comportement des particules lors de la conception de réseaux de DLD. Par ailleurs, dans une approche orientée système, nous proposons également un packaging fluidique des dispositifs de DLD. Plusieurs étapes de tri étant généralement requises pour la purification d’échantillons biologiques, nos développements portent également sur la façon d’interconnecter ces modules au sein d'une configuration en série. Deux applications biologiques sont adressées et démontrent la versatilité de la technologie de DLD : l'isolement de bactéries E. coli à partir de prélèvements sanguins humains - en vue du diagnostic du sepsis - et l'extraction d'EVs dans des milieux de culture cellulaires - avec en perspective la détection d'EVs spécifiques par biopsie liquide. L'étape de préparation d'échantillon ne peut être dissociée de l'étape de caractérisation. C'est pourquoi, l'isolement des EVs devra dans un second temps être couplé à leur analyse au sein d'un dispositif intégré, portable et autonome, ce qui pourrait ouvrir de nouvelles perspectives vers l'application clinique des recherches actuelles sur les EVs. / Over the past decades, Extracellular Vesicles (EVs) have demonstrated strong potential as new biomarkers for liquid biopsy. Indeed, since EVs are fingerprints of parent cells, they can be exploited as early diagnostic tools. However, owing to their small size and high heterogeneity, EVs are challenging to extract from biofluids. In particular, reproducible and standardized protocols are required to perform fast, efficient, and cost-effective preparation of undamaged EV subpopulations from limited sample volumes. Deterministic Lateral Displacement (DLD) appears to be a promising microfluidic technology for this preparation by means of passive and label-free separation. DLD performs size-based separation of particles around a critical diameter that can be fine-tuned according to design parameters in an array of micropillars. Across the numerous biotechnological applications of DLD, none has yet successfully performed the complete extraction of EVs from unprocessed biofluids. This is the underlying motivation of this thesis, which outlines technological enhancements that make DLD separation more predictable, efficient, and easy-to-integrate. Based on both numerical and experimental developments, predictive models are proposed in order to anticipate particle behavior and to help in the design of efficient DLD devices. In addition to the optimization of single DLD devices, this thesis also addresses the issue of system integration. An innovative approach of serial connection between DLD modules is proposed to address the sequential sorting of particles from a complex biofluid and ensure that there is no loss of function of individual DLD devices when operated alone or in series. Two biological applications illustrate the potential of DLD-based sample preparation systems: the isolation of E. coli bacteria from human blood samples for sepsis diagnostics and the extraction of EVs from cell culture media with the perspective of liquid biopsy applications. And as sample preparation cannot be dissociated from detection or characterization, this thesis moreover highlights the potential integration of DLD in an all-in-one microfluidic device for both sample preparation and analysis of extracted EVs. Such a portable and autonomous device could overcome some of the current limitations with regard to the clinical use of EVs.

[pt] A eficiência do processo de injeção de água, o método de recuperação secundária mais comum na indústria do petróleo, é limitada por seu padrão de varredura não uniforme, originado da formação de caminhos preferenciais devido à alta razão de mobilidade entre água e óleo, e a elevada saturação de óleo residual, associada aos efeitos capilares. A fim de melhorar a recuperação de petróleo, diferentes abordagens têm sido sugeridas na literatura, com algumas delas baseadas no bloqueio de poros e consequente desvio de água, varrendo assim uma área maior do reservatório e deslocando mais do óleo aprisionado por capilaridade. O bloqueio de poros pode ser realizado com diferentes métodos, sendo um deles a injeção de emulsão, com a fase dispersa, composta por gotas de óleo, atuando como o agente responsável pela diminuição da mobilidade da fase aquosa. Neste trabalho, os mecanismos fundamentais do processo de injeção de emulsão foram estudados experimentalmente, visualizando-se o escoamento em escala de poros em um dispositivo micro-fluídico de vidro composto por uma rede de canais constritos, que modela as principais características de um meio poroso. Os resultados mostram o efeito do tamanho da gota e do número de capilaridade no padrão do escoamento, no tamanho dos gânglios do óleo aprisionado e na recuperação de óleo residual. / [en] The efficiency of water flooding, the most common secondary recovery method in the oil industry, is limited by its non-uniform sweep pattern, originating from the formation of preferential paths because of the high mobility ratio between water and oil, and the high residual oil saturation, associated with capillary oil trapping. In order to improve oil recovery, different approaches have been suggested in the literature, with some of them based on pore blocking and consequent water diversion, thus sweeping a bigger area of the reservoir and displacing more of the trapped oil. Pore blockage can be performed with different methods, one of which is emulsion flooding, with the disperse phase, composed by oil drops, acting as the agent responsible for the decreased water phase mobility. In this work, the fundamental mechanisms of emulsion flooding process was studied experimentally, by visualizing the pore-scale flow in a glass microfluidic device composed of a network of constricted channels, that models the main features of a porous media. The results show the effect of drop size and capillary number on the flow pattern, trapped oil ganglia size and residual oil recovery.

A structure subjected to extreme load due to explosion or human error may lead to progressive collapse. One of the direct methods specified by design guidelines for assessing progressive collapse is the Alternate Load Path method which involves removal of a structural member and analysing the structure to assess its potential of bridging over the removed member without collapse. The use of this method in assessing progressive collapse therefore requires that the vertical load resistance function of the bridging beam assembly, which for a typical laterally restrained reinforced concrete (RC) beams include flexural, compressive arching action and catenary action, be accurately predicted. In this thesis, a comprehensive study on a reliable prediction of the resistance function for the bridging RC beam assemblies is conducted, with a particular focus on a) the arching effect, and b) the catenary effect considering strength degradations. A critical analysis of the effect of axial restraint, flexural reinforcement ratio and span-depth ratio on compressive arching action are evaluated in quantitative terms. A more detailed theoretical model for the prediction of load-displacement behaviour of RC beam assemblies within the compressive arching response regime is presented. The proposed model takes into account the compounding effect of bending and arching from both the deformation and force points of view. Comparisons with experimental results show good agreement. Following the compressive arching action, catenary action can develop at a much larger displacement regime, and this action could help address collapse. A complete resistance function should adequately account for the catenary action as well as the arching effect. To this end, a generic catenary model which takes into consideration the strength degradation due to local failure events (e.g. rupture of bottom rebar or fracture of a steel weld) and the eventual failure limit is proposed. The application of the model in predicting the resistance function in beam assemblies with strength degradations is discussed. The validity of the proposed model is checked against predictions from finite element model and experimental tests. The result indicate that strength degradation can be accurately captured by the model. Finally, the above developed model framework is employed in investigative studies to demonstrate the application of the resistance functions in a dynamic analysis procedure, as well as the significance of the compressive arching effect and the catenary action in the progressive collapse resistance in different designs. The importance of an accurate prediction of the arching effect and the limiting displacement for the catenary action is highlighted.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-05T20:12:22Z No. of bitstreams: 1 DORIVAL LOBATO JÚNIOR - DISSERTAÇÃO PPGMAT 2005..pdf: 658187 bytes, checksum: 934af5bed920aceba4c0f48a5fbca2d6 (MD5) / Made available in DSpace on 2018-07-05T20:12:22Z (GMT). No. of bitstreams: 1 DORIVAL LOBATO JÚNIOR - DISSERTAÇÃO PPGMAT 2005..pdf: 658187 bytes, checksum: 934af5bed920aceba4c0f48a5fbca2d6 (MD5) Previous issue date: 2005-08 / Neste trabalho, estudamos a influência local em modelos de regressão.Este método foi proposto inicialmente por Cook (1986) e tem se mostrado como um poderoso instrumento da análise de diagnóstico. A proposta de Cook consiste em avaliar a curvatura normal de uma superfície, baseada na medida Likelihood Displacement, sob uma pequena peturbação no modelo. Em seguida apresentamos a abordagem de Billor e Loynes (1993), que aplicam uma medida Likelihood Displacement modificada, cuja primeira deriva da não se anula, exceto em casos triviais, com isso a inclinação máxima é usada como medida de influência local. No final, discutimos três aplicações onde utilizamos algumas técnicas gráficas de diagnóstico e as duas propostas de influência local aqui referidas. / In this work, we study the local influence in regression models, this method was offer first of all by Cook(1986) and have show how an important instrument of the diagnostics analysis. The Cook's approach consist in assessing the normal curvature of the geometric surface, using the measure Likelihood Displacement, under an minor perturbations of statistical model. After we present the approach of the Billor and Loynes (1993), that apply an measure Likelihood Displacement changes whose first derivative does not, except in trivial cases, vanish.Thus the maximum slop is using how measure of the local influuence. In finish, we present three apply where use any technic graphics of the diagnostics and the two proposed of the local influence here reported.

L’objectif de ce travail a été de proposer une méthode de détection de défaut pour le déplacement longitudinal du chariot mobile du Radiotélescope de Nançay. L’importance de l’implémentation d’une procédure de détection des défauts a été mise en évidence grâce à la description des besoins du personnel en charge de la maintenance de cet instrument scientifique. Ce mémoire débute par un état de l’art sur différentes méthodes de diagnostic (détection et isolation des défauts), une analyse critique de ces méthodes est réalisée. Nous rappelons ensuite les notions d’observabilité avant de présenter l’observateur de Newton et l’observateur de Ciccarella. L’extension de ce dernier aux systèmes MIMO est réalisée par la suite. Une comparaison de ces différents observateurs termine le chapitre 2. Le chapitre 3 présente le Radiotélescope de Nançay et plus particulièrement la modélisation du déplacement longitudinal du chariot mobile. Une étude des propriétés du modèle est abordée par la suite. Le dernier chapitre traite de la validation partielle du modèle obtenu au chapitre précédent. Ensuite, l’utilisation des relations de redondances analytiques a permis de mettre en évidence la faisabilité du diagnostic sur l’application. L’utilisation de l’extension de l’observateur de Ciccarella pour le diagnostic permet de réaliser la détection de défaut capteur en utilisant un banc d’observateurs. Le suivi de paramètres du modèle permet de suivre l’évolution du système (vieillissement par exemple) et la détection de défaut actionneurs. Dans l’ensemble, les résultats obtenus permettent de conclure sur la bonne détection des défauts capteurs et actionneurs. / The aim of this work was to propose a fault detection method for the longitudinal displacement of the mobile cart of the Radiotelescope of Nançay. The importance of the implementation of a procedure of detection of the defects was highlighted thanks to the description the needs of the personnel in charge of maintenance for this scientific instrument. This memory begin with a state of the art on various methods of diagnosis (detection and isolation of the default), a critical analysis of these methods is carried out. We point out then the concepts of observability before presenting the Newton observer and the Ciccarella observer. The extension of this last to systems MIMO is carried out thereafter. A comparison of these various observers finishes chapter 2. Chapter 3 presents the Radiotelescope of Nançay and more particularly the modelling of the longitudinal displacement of the mobile cart. A study of the properties of the model is approached thereafter. The final chapter covers validation partial of the model obtained in the preceding Chapter. Then, the use of analytical redundancy relations made it possible to highlight the feasibility of the diagnosis on the application. The use of the extension of the Ciccarella observer for the diagnosis makes it possible to carry out the detection of sensor fault by using a bench of observers. The follow-up of parameters of the model makes it possible to follow the evolution of the system (ageing for example) and the detection of defect actuators. As a whole, the results obtained make it possible to conclude on good detection from the sensor and actuator faults.

Sistemas integrados de lavoura e pecuária têm, por paradigma, o efeito do animal no sistema. Esse efeito é função, dentre outros, do manejo da intensidade de pastejo e de como os animais reagem às estruturas de pasto decorrentes. O propósito deste estudo foi avaliar o comportamento em pastejo de novilhos de corte em diferentes estruturas de pasto e seus padrões de deslocamento. Investigou-se a hipótese de que diferentes alturas promoveriam alterações nos padrões de comportamento dos animais em pastejo. Neste sentido, este experimento foi conduzido em uma área de integração lavoura-pecuária da Fazenda do Espinilho, município de Tupanciretã – RS, de julho a novembro de 2005, em pastagem de azevém anual (Lolium multiflorum Lam.) e aveia preta (Avena strigosa Schreb.), que sucedia uma lavoura de soja. Manejou-se o pasto sob lotação contínua, com carga variável, em quatro alturas (tratamentos), a saber: 10, 20, 30, 40 cm, distribuídos em um delineamento experimental de blocos casualizados com três repetições. As avaliações foram realizadas no período diurno, por observação visual direta, em três datas de avaliações, duas delas coincidindo ao estádio vegetativo e a terceira ao reprodutivo. As diferentes estruturas criadas foram resultado de diferentes disponibilidades de forragem tendo em vista o aumento linear da massa de forragem (P<0,0001) com o aumento da altura do pasto. Em situações de menor disponibilidade de forragem observou-se que os animais apresentam comportamento de pastejo compensatório, aumentando seu tempo de pastejo diário (P=0,0208) e apresentando ciclos mais longos de refeições (P=0,0302). Além do mais, aumentam a taxa de bocados (P<0,0001), o número total de estações alimentares visitadas (P=0,0009), o número de bocados por estação alimentar (P= 0,0178), o número total de bocados (P<0,0001) e reduzem o tempo de ruminação (P=0,0443) e o tempo de permanência na estação alimentar (P=0,0142). Em termos de deslocamento, verificou-se que os animais procedem menos passos entre estações alimentares (P=0,0115) quando a forragem é limitante, porém, o número total de passos verificados é maior (P=0,0033) ao longo do período de pastejo. Para concluir, confirmou-se a hipótese de que os animais modificam seu comportamento em diferentes estruturas de pasto e, principalmente, alteram seu padrão de deslocamento, o que poderá implicar em conseqüências de impacto num sistema de integração lavoura-pecuária. / The animal’s effect in the system is a paradigm in integrated crop-livestock operations. This effect is a function, among others, of the management of the grazing intensity and how animals react to the sward structures. The purpose of this study was to evaluate steers grazing behaviour in different sward structures and their displacement patterns. The hypothesis that different heights could promote changes in the ingestive behavior of animals was tested. In this sense, the experiment was conducted in an integrated crop/livestock area at Espinilho farm, Tupanciretã/RS/Brazil (Fazenda do Espinilho), from July to November 2005, in Italian ryegrass (Lolium multiflorum Lam.) and black oat (Avena Strigosa Schreb.) pasture succeeding soybean. The pasture was managed with continuous variable stocking at 10, 20, 30 and 40 cm sward height distributed in a completely randomized block design with three replicates. Data was recorded by visual assessment, from sunrise until sundown, in three evaluation dates, two in the vegetative stage and one in the reproductive stage. Different structures were created as a result of the linear increasing in herbage masses (P<0.0001) with increasing sward height. In limited herbage situation animals present compensatory behaviour, increasing their daily grazing time (P=0.0208) and presenting longer meal lengths (P=0.0302). Moreover, animals increase bite rate (P<0.0001), the number of visited feeding stations (P=0.0009), the number of bites per feeding station (P= 0.0178), the total number of bites (P<0.0001) and decrease ruminating time (P=0.0443) and time per feeding station (P=0.0142). In terms of animal displacement, it was verifyied they proceed less steps between feeding stations (P=0.0115) with limited herbage, however, the total number of steps is greater (P=0.0033) along the grazing period. To conclude, the hypothesis that animals modify their behaviour in different sward structures was confirmed and, mainly modifies their displacement patterns with potential consequences to integrated crop-livestock systems.

This works presents a comparative analysis of heterosemantic words from portuguese and spanish. The research was motivated as a result of observing either the change or the displacement of meaning which occurs in substantially similar words in both languages, as well as by observing their relative frequency both in texts and in the (spoken / written) productions of natives and students of a foreign language. The main inquiry specifically turns to a lexical-semantic problem. Namely, what would probably be the reasons for a semantic discrepancy between two substantially identical words in genetically related languages? Is the problem of divergence in the meaning of these lexemes specifically semantic or do other linguistic levels imbricate? Do these lexemes comprise any kind of semantic or of meaning relations, which explains this phenomenon? If so, how does this relation occur either in both languages or in one of them in particular? Thus, this work intends to comparatively describe these lexemes by classifying and analysing them through semantic relations of polysemy and homonymy, and also identify the reasons for their change or displacement of meaning. The corpus of analyses is constituted of paired portuguese and spanish lexical words, phonetically or graphically similar, which are considered as being heterosemantic for their similarity on the expression level (sound) and different on the contents level (meaning). The etymology of these words is described as well their primary and secondary meanings, which, in turn, are exemplified by sentences observed in the formal and informal use of language, spoken or written, which are found in books, texts and dictionaries, as well as in the speakers spontaneous utterances of these languages. The work presents an eminently explanatory character toward the treatment of data, basically under a diachronic and structuralist perspective, since it turns to historical and etymological aspects, by making explicit the reasons of the changes or displacement of meaning. It is also intended with this work, to have this semantic divergence explained through the semantic relations of polysemy and homonymy. On one hand, the work is theoretically founded on the postulates of the Applied Linguistics, focalizing at the interference/interlanguage notion and at the delimitation and classification of heterosemantics. On the other hand, it searches the General Linguistics and the Semantic Linguistics when specifically dealing with lexical-semantic matters in the light of the semantic line referred to as pre-Structuralist, preconized by Saussure , and in the discussions by Ullmann, Guiraud, Lyons. The linguistic sign and its nature, the arbitrariness and mutability, the linguistic value, the semantic relations of polysemy and homonymy are, among other topics discussed. Thus, from the comparative analysis of data, the heterosemantics are classified in: homonymous and polysemics, which are divided into four sub-groups stemmed from distinct linguistic processes. In summary, the true heterosemantics (the homonymous ones) arise from phonetic evolution, or from semantic divergences in their origin; the accidental heterosemantics (the polysemic ones) become as they are from semantic evolution, displacement of meaning, or distinct semantic features. Portuguese is also thought to have more motivated lexemes than spanish, for the degree of arbitrariness and motivation is different in both languages; although the confronted languages have a number of cognates in common, it is also confirmed that they become heterosemantic, because of semantic displacement or changes which have occurred in each language in particular. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Este trabalho apresenta uma análise comparativa de palavras heterossemânticas do português e do espanhol. A pesquisa foi motivada face à observação da mudança ou deslocamento de sentido ocorrido em palavras substancialmente semelhantes nas duas línguas, e sua relativa freqüência em textos, e em produções (falada ou escrita) de nativos e aprendizes de uma língua estrangeira. O questionamento principal volta-se especificamente para um problema léxico-semântico. Isto é, quais seriam as possíveis causas para a divergência semântica entre duas palavras substancialmente idênticas em línguas geneticamente relacionadas? O problema da divergência de sentidos nesses lexemas é especificamente semântico ou outros níveis lingüísticos se imbricam? Há algum tipo de relação semântica ou de significado nesses lexemas que explique esse fenômeno? Se há, como essa relação ocorre nas duas línguas, e/ou em cada língua particular? Assim, procura-se descrever comparativamente esses lexemas classificando-os e analisando-os através das relações semânticas de polissemia e homonímia, e identificar as causas que promovem a mudança ou o deslocamento de sentido neles. O corpus constitui-se de pares de palavras lexicais do português e do espanhol semelhantes fonética ou graficamente, e consideradas heterossemânticas por serem semelhantes no plano da expressão (som) e divergentes no plano do conteúdo (significado). Descreve-se sua etimologia, seus sentidos primários e secundários, exemplificando cada um dos sentidos com sentenças observadas no uso formal e informal da língua, escrito ou falado, presentes em livros, textos e dicionários, e ainda no uso espontâneo de informantes dessas línguas. O trabalho apresenta um carácter eminentemente explicativo quanto ao tratamento dos dados, diante de uma perspectiva, basicamente, diacrônica e estruturalista pois volta-se para aspectos históricos e etimológicos, explicitando as causas das mudanças ou deslocamento de sentido. Procura-se comprovar também que essa divergência semântica pode ser explicada através das relações semânticas de polissemia e homonímia. Fundamenta-se, teoricamente, por um lado, nos postulados da Lingüística Aplicada, visando à questão da interferência/interlíngua, à delimitação e classificação dos heterossemânticos. Por outro lado, ao tratar especificamente sobre as questões léxico-semânticas, recorre-se à Lingüística Geral e à Semântica Lingüística, dentro da linha semântica denominada pré-Estruturalista preconizada por Saussure, e em discussões de Ullmann, Guiraud, Lyons. Discute-se sobre o signo lingüístico e sua natureza, sobre arbitrariedade e mutabilidade, valor lingüístico, sobre as relações semânticas de polissemia e homonímia, as causas de mudanças ou deslocamento de sentido, e outras questões que envolvem o problema. Assim, da análise comparativa dos dados, classificam-se os heterossemânticos em: homônimos e polissêmicos, e estes, em quatro subgrupos advindos de processos lingüísticos distintos. Em síntese, os heterossemânticos propriamente ditos (homônimos) surgem por evolução fonética, ou por divergências semânticas na origem ou base; os heterossemânticos acidentais (polissêmicos) tornam-se tais por evolução semântica, deslocamento de sentido, ou traços semânticos distintos. Acredita-se também que o português possui mais lexemas motivados do que os mesmos do espanhol, pois o grau de arbitrariedade e motivação é diferente em ambas; confirma-se ainda que apesar de as línguas confrontadas terem inúmeros cognatos entre si, os mesmos tornam-se heterossemânticos, devido ao deslocamento ou mudanças semânticas ocorridos em cada língua particularmente.