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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Vznik a ukončení nenarozeného života / Birth and termination of unborn life

LUŇÁKOVÁ, Jana January 2011 (has links)
The thesis deals with the problem of the origin of human life and abortion. It focuses on different approaches to the question as to when unborn human life becomes a person, and, consequently, when it should be guaranteed the right to life. The thesis is divided into four main chapters corresponding to four main aspects of the issue of abortion. The first chapter provides information from embryological (biological creation of man) and medical (abortion) perspective. The second chapter deals with the abortion legislation in the Czech Republic (history and current situation). The third chapter examines different ethical questions such as identity of the person, the right to decide about their own body, etc. The last chapter gives an account on person and abortion from the Christian point of view.
32

Um estudo sobre o ensino dos temas “Origem da Vida” e “Evolução Biológica” em dissertações e teses brasileiras (2006 a 2016) / A study on the teaching of “Origin of Life” and “Biological Evolution” in brazilian dissertations and theses.

Zabotti, Kamilla 19 February 2018 (has links)
Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2018-05-23T14:46:05Z No. of bitstreams: 2 Kamilla Zabotti.pdf: 2089112 bytes, checksum: ee20e95dae4d0db862aee5132206694c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-23T14:46:05Z (GMT). No. of bitstreams: 2 Kamilla Zabotti.pdf: 2089112 bytes, checksum: ee20e95dae4d0db862aee5132206694c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / The integrated understanding of the natural phenomena and biological process occurs thought the evolutionary thought, thus the Biological Evolution is considered the integrating and unifying base of Biological Science. Though the teaching of how life originated and diversified are the object of researches already developed and published in the last decades, some difficulties still remain in teaching these subjects. Taking these considerations into account, the present research is characterized as State of Art and it aims to highlight what is being produced in academic researches, in the form of dissertations and theses, from 2006 to 2016, regarding the teaching of the themes Origin of Life and Biological Evolution. A total of 78 articles were found, being 65 (83%) dissertations and 16 (17%) theses. 86% of these are from Higher Education Institutions (HEIs) of public administrative nature, with emphasis on state and federal universities, and 13% of private HEIs. Around 80% of dissertations and thesis are concentrated in the South-Southeast region. Half of the papers are dissertations on teaching Biological Evolution, and only one thesis investigates the teaching of the Origin of Life. Around 70% of the academic productions identified are intended for research at the secondary level on basic education. The continuing formation of teachers contemplates only 4% of the productions. In relation to the most prevalent issues in the set of dissertations and theses, stand out: Characteristic of Teacher, with 25%, followed by Didactic Resources and Method-Contents with almost 16% each, and History and Philosophy of Science, with 14%. We found three issues that were not well investigated in the researches: Curriculum and Programs, Non-Formal Education and School Organization, which appears as a research field little explored and that requires an investigation on the teaching and learning process of the Origin and Evolution of Life. These results, as well as the researches focused on the analysis of academic production, can contribute to the deployment of more specific proposals of teaching formation and improvements in the teaching-learning of the Origin of Life and Biological Evolution. / A compreensão integrada dos fenômenos naturais e processos biológicos ocorre por meio do pensamento evolutivo, assim, a Evolução Biológica é considerada o eixo integrador e unificador das Ciências Biológicas. Embora o ensino de como a vida se originou e se diversificou sejam objetivos de pesquisas já desenvolvidas e publicadas nas últimas décadas, persistem algumas dificuldades no ensino desses temas. Levando em conta tais observações, a presente pesquisa é caracterizada como Estado da Arte e tem por objetivo evidenciar o que está sendo produzido nas pesquisas acadêmicas, na forma de dissertações e teses, no período de 2006 a 2016, quanto ao ensino dos temas Origem da Vida e Evolução Biológica. No total, foram encontrados 78 trabalhos, sendo 65 (83%) dissertações e 13 (17%) teses. 86% desses trabalhos são de instituições de ensino superior (IES) de natureza administrativa pública, com destaque para as universidades estaduais e federais, e 13% de IES de natureza privada. Em torno de 80% das dissertações e teses estão concentradas no eixo Sul-Sudeste. Metade dos trabalhos são dissertações, acerca do ensino da Evolução Biológica, e somente uma tese investiga exclusivamente o ensino da Origem da Vida. Em torno de 70% das produções encontradas são destinadas a investigações no ensino médio na educação básica. A formação continuada de professores contempla somente 4% das produções. Quanto às problemáticas que mais prevaleceram no conjunto de dissertações e teses, destacam-se: Características do Professor, com 25%, seguida de Recursos Didáticos e Conteúdo-Método, com quase 16% cada, e História e Filosofia da Ciência, com 14%. Identificamos três problemáticas pouco investigadas nas pesquisas: Currículos e Programas, Educação Não-Formal e Organização da Escola, configurando-se como um campo de pesquisa pouco explorado e que carece de investigações acerca dos processos de ensino e aprendizagem da Origem e Evolução da Vida. Os resultados desta pesquisa, bem como a realização de pesquisas dedicadas à análise do conjunto da produção acadêmica, podem contribuir para a implantação de propostas mais específicas na formação de professores e melhorias no ensino e na aprendizagem da Origem da Vida e Evolução Biológica.
33

Nucléotides à l'interface minéral-eau et réactivité des acides aminés en conditions hydrothermales dans le contexte des origines de la vie / Nucleotides at the mineral-water interface and reactivity of amino acids under hydrothermal conditions in the context of the origins of life

Pedreira-Segade, Ulysse 15 September 2017 (has links)
Les découvertes de traces de vie primitive, fossiles et biosignatures, suggèrent que celle-ci serait apparue il y 4,3 à 3,7 milliards d’années. Cette émergence est le résultat d’étapes menant des plus simples molécules organiques aux premières formes de vie unicellulaire.Ce travail de thèse examine l’hypothèse de l’apparition de la vie dans un environnement hydrothermal, dans lequel la pression, les gradients de température et de pH, la diversité des surfaces minérales et l’abondance d’énergie chimique auraient permis l’accumulation et la complexification de la matière organique. Il s’intéresse particulièrement aux étapes de concentration des nucléotides et de polymérisation des acides aminés, respectivement briques élémentaires du matériel génétique et des protéines, inhérentes au vivant.Cette thèse présente d’abord une étude des interactions de surfaces entre nucléotides en solution et minéraux en feuillets en conditions contrôlées de température, de pH et de salinité. Dans une deuxième partie, elle récapitule les résultats obtenus par l’observation in situ de l’effet des conditions hydrothermales et des surfaces minérales sur la polymérisation des acides aminés non activés.Ce travail suggère que les minéraux en feuillets, et plus particulièrement les argiles gonflantes, augmentent la concentration locale en nucléotide de trois ordres de grandeurs au moins en présentant un comportement très dépendant des conditions physicochimiques du milieu. De plus, il reconfirme l’importance de la température dans la polymérisation des acides aminés en solution, mais montre également que la pression et la présence de surfaces minérales ont une influence majeure sur la réactivité de ces molécules. Les environnements hydrothermaux semblent donc favorables à la concentration, la préservation et la complexification de la matière organique, étapes essentielles à l’émergence des propriétés du vivant. / The discovery of traces of primitive life, such as fossils and biosignatures, suggests that life may have appeared some 4.3 to 3.7 billion years ago. This emergence resulted from a chemical evolution with steps leading from simple organic molecules to the first single-celled organisms.This thesis tests the hypothesis of a hydrothermal origin of life. In such geochemical settings, pressure, temperature and pH gradients, mineral surfaces diversity and abundant chemical energy would have favored the accumulation and complexification of organic matter. This work focuses on the concentration of nucleotides and the polymerization of amino acids, which are the building blocks of genetic material and proteins, respectively.The first part of this thesis presents a large study of the interactions between nucleotides in aqueous solutions and phyllosilicates under controlled conditions of temperature, pH and salinity. The second part describes an in situ study of the effects of hydrothermal conditions and mineral surfaces in the polymerization of non-activated amino acids.This work suggests that sheet minerals, and especially swelling clays, increase the local concentration of nucleotides by three orders of magnitude and exhibit an adsorption behavior that is very dependent on the physical and chemical conditions of the environment. Moreover, this work confirms that the polymerization of amino acids in aqueous solutions is sensitive to temperature and it also underlines that pressure and mineral surfaces have a major role on the reactivity of these molecules. Hydrothermal environments thus favor the concentration, preservation and complexification of organic matter. These are crucial steps for the emergence of the properties of life in the chemical evolution.
34

The dynamics of chemically active droplets

Seyboldt, Rabea 16 June 2020 (has links)
In unserem täglichen Leben begegnen wir Tropfen oft in physikalischen Systems, beispielsweise als Öltropfen in Salatsoße. Diese Tropfen sind meist chemisch inaktiv. In biologischen Zellen bilden Proteine und RNA zusammen Tropfen. Zellen sind chemisch aktiv, so dass die Tropfenkomponenten neu gebildet, abgebaut und modifiziert werden können. In dieser Doktorarbeit wird das dynamische Verhalten von chemisch aktiven Tropfen mit analytischen und numerischen Methoden untersucht. Um das dynamische Verhalten von solchen aktiven Tropfen zu untersuchen, benutzen wir ein Minimalmodell mit zwei Komponenten, die zwei Phasen bilden und durch chemische Reaktionen ineinander umgewandelt werden. Die chemischen Reaktionen werden durch das Brechen von Detailed Balance aus dem Gleichgewicht gehalten, so dass die Tropfen chemisch aktiv sind. Wir konzentrieren uns auf den Fall, in dem Tropfenmaterial im Tropfen in die äußere Komponente umgewandelt wird, und in der äußeren Phase erzeugt wird. Wir finden ein vielfältiges dynamisches Phasendiagramm mit Regionen, in denen Tropfen schrumpfen und verschwinden, Regionen, in denen Tropfen eine stabile stationäre Größe besitzen, und Regionen, in denen eine Forminstabilität zu komplexer Tropfen-Dynamik führt. In der letzten Region deformieren sich Tropfen typischenweise prolat, verformen sich zu einer Hantel, und teilen sich in zwei Tochtertropfen, die wieder anwachsen. Dies kann zu Zyklen von Wachstum und Teilung von Tropfen führen, bis die Tropfen das gesamte Volumen füllen. Während spherische Tropfen durch die chemischen Reaktionen entgegen ihrer Oberflächenspannung deformiert werden, können Tropfen- Zylinder und Platten durch chemische Reaktionen stabilisiert werden. Generell ist die Dynamik von Tropfen ein hydrodynamisches Problem, da die Oberflächenspannung von deformierten Tropfen hydrodynamische Flüsse erzeugt. Wir finden, dass chemische Reaktionen entgegen die Oberflächenspannung Arbeit verrichten können, so dass die Tropfenteilung auch unter Berücksichtigung hydrodynamischer Flüsse möglich ist. Diese Doktorarbeit zeigt, dass die Kombination von chemische Reaktionen und Phasenseparation unter Nichtgleichgewichtsbedingungen zu neuem dynamischen Verhalten führen kann. Die Ergebnisse zeigen die Relevanz von chemischen Reaktionen zum Verständnis von Phasenseparation in biologischen Systemen auf, und können bei der Umsetzung der diskutierten Phänomene in experimentellen Systemen helfen. Die Tropfenteilung, die in dieser Doktorarbeit diskutiert wird, erinnert an die Teilung von biologischen Zellen. Davon motiviert schlagen wir vor, dass die Teilung von chemisch aktiven Tropfen ein Mechanismus für die Replikation von Tropfen-artigen Protozellen am Ursprung des Lebens gewesen sein könnte.:1. Introduction 2. Theory of multi-component phase-separating systems with chemical reactions 3. Minimal model for chemically active droplets in two formulations 4. Shape instability of spherical droplets with chemical reactions 5. Dynamical behavior of chemically active droplets 6. Shape instability of droplets with various geometries 7. Role of hydrodynamic flows in chemically driven droplet division 8. Chemically active droplets as a model for protocells at the origin of life 9. Conclusion Appendices / In our everyday environment, we regularly encounter liquid-liquid phase separation in physical systems such as oil droplets in vinegar. These droplets tend to be chemically inert. In biological cells, protein and RNA may together form liquid droplets. Cells are chemically active, so that droplet components can be created, degraded and modified. In this thesis we study the influence of nonequilibrium chemical reactions on the shape dynamics of a droplet theoretically, using analytical and numerical methods. To discuss the dynamical behavior that results from combining phase separation and chemical reactions in sustained nonequilibrium conditions, we introduce a minimal model with only two components that separate into distinct phases. These two components are converted into each other by chemical reactions. The reactions are kept out of equilibrium by breaking of detailed balance, so that the droplet becomes active. We concentrate on the case where the reaction inside the droplet degrades droplet material into the outer component, and where the reaction outside creates new droplet material. We find that chemically active droplets have a rich dynamic phase space, with regions where droplets shrink and vanish, regions where droplets have a stable stationary size, and regions where the flux-driven instability leads to complex dynamic behavior of droplets. In the latter, droplets typically elongate into a dumbbell shape and then split into two symmetrical daughter droplets. These droplets then grow until they have the same size as the initial droplet. This can lead to cycles of growth and division, so that an initial droplet divides until droplets fill the simulation volume. We analyze the stationary spherical state of the droplet, which is created by a balance of the fluxes driven by the chemical reactions. We find that stationary droplets may have a shape instability, which is driven by the continuous fluxes across the droplet interface and which may trigger the division. We also find that while reactions may destabilize spherical droplet shapes despite the surface tension of the droplet, they can have stabilizing effects on cylindrical droplets and droplet plates. Generally, the shape dynamics of droplets is a hydrodynamic problem because surface tension in non-spherical droplets drives hydrodynamic flows that redistribute material and deform the droplet shape. We therefore study the influence of hydrodynamic flows on the shape changes of chemically active droplets. We find that chemical reactions in active droplets can perform work against surface tension and flows, so that the droplet division is possible even in the presence of hydrodynamic flows. The present thesis highlights how the combination of basic physical behaviors – phase separation and chemical reactions – may create novel dynamic behavior under sustained nonequilibrium conditions. The results demonstrate the importance of considering chemical reactions for understanding the dynamics of droplets in biological systems, as well as proposes a minimalist model for experimentalists that are interested in creating a system of dividing droplets. Finally, the division of chemically active droplets is reminiscent of the division of biological cells, and it motivates us to propose that chemically active droplets could have provided a simple mechanism for the self-replication of droplet-like protocells at the origin of life.:1. Introduction 2. Theory of multi-component phase-separating systems with chemical reactions 3. Minimal model for chemically active droplets in two formulations 4. Shape instability of spherical droplets with chemical reactions 5. Dynamical behavior of chemically active droplets 6. Shape instability of droplets with various geometries 7. Role of hydrodynamic flows in chemically driven droplet division 8. Chemically active droplets as a model for protocells at the origin of life 9. Conclusion Appendices
35

[pt] ANÁLISE POR FTIR DA RADIÓLISE E DO SPUTTERING DE BASES NITROGENADAS IRRADIADAS POR ELÉTRONS DE (KE)V SOB CONDIÇÕES ASTROFÍSICAS / [en] RADIOLYSIS AND SPUTTERING FTIR ANALYSIS OF NITROGENOUS BASES IRRADIATED BY (KE)V ELECTRONS UNDER ASTROPHYSICAL CONDITIONS

VINICIUS PESSANHA REGO 21 June 2022 (has links)
[pt] A origem da vida ainda é uma questão aberta na ciência. Dentre as possíveis respostas, a panspermia é uma alternativa amplamente discutida. Ao investigar esta possibilidade, o desenvolvimento de modelos que descrevam o comportamento de moléculas interagindo com raios cósmicos são de extrema importância. Para esta finalidade, filmes finos de diferentes espessuras de bases nitrogenadas - adenina, citosina, guanina e timina - foram depositados sobre pastilhas de ZnSe para serem irradiados por elétrons de 1,0 e 0,50 keV. A adenina foi irradiada sob diferentes temperaturas. Após cada irradiação parcial, a espectroscopia óptica na região do infravermelho (FTIR) foi usada para monitorar as modificações nas características espectrais. Observou-se que a seção de choque de destruição das bases nitrogenadas irradiadas é aproximadamente 10 elevado a -16 cm quadrados e, para a adenina, este valor aumenta para temperaturas baixas. Com base nos dados obtidos de glicina, o tempo de meia vida de adenina pura processada por vento solar a 1 UA estimado é de cerca de 40 dias. A seção de choque varia muito pouco quando as espessuras dos filmes são aumentadas de 10 para 30 nm, e os valores encontrados para as quatro bases seguem a ordem: citosina, adenina, guanina e timina, respectivamente, da menos para a mais radioresistente. Para melhor compreender o significado dos resultados experimentais, previsões foram obtidas com o algoritmo CASINO-estendido e apresentam bom acordo se radiólise e sputtering são considerados. / [en] The origin of life is still an open question in science. Among the possible answers, panspermia is a widely discussed alternative. To investigate this possibility, the development of models that describe the behavior of molecules interacting with cosmic rays is extremely important. For this purpose, thin films of different thicknesses of nitrogenous bases - adenine, cytosine, guanine, and thymine - were deposited on ZnSe disks to be irradiated by 1.0 and 0.50 keV electrons. Adenine was irradiated under different temperatures. After each partial irradiation, optical spectroscopy in the infrared region (FTIR) was used to monitor changes in spectral characteristics. It is observed that the destruction cross sections of irradiated nitrogenous bases are approximately 10 raised to -16 square cm and, for adenine, this value increases at low temperatures. In comparition to glycine data, the estimated half-life of pure adenine when processed at 1 au by the solar wind is about 100 days. The cross section varies very little when the film thicknesses are increased from 10 to 30 nm, and the bases follow the order: cytosine, adenine, guanine and thymine, respectively, from the least to the most radioresistant. To better analyze the experimental data, they are compared with predictions obtained with the CASINOextended algorithm. They are in good agreement if radiolysis and sputtering are considered.
36

The self-assembly of nucleic acid bases on metal and mineral surfaces

Shvarova, Olga Y. January 2011 (has links)
The ability of RNA bases to self-assemble into larger structures is an important research area relevant to the origins of life. In the RNA helix the bases are arranged on a sugar-phosphate carcass but it has been suggested that the initial ordering could form on a flat surface. This thesis is an attempt to establish experimentally whether the complementary RNA bases, adenine and uracil, have the ability to self-assemble into large ordered structures when adsorbed on metal and mineral surfaces. The Au (111) surface was chosen as a preferred substrate as it is flat, relatively free of defects, chemically inert and reconstructs in a characteristic pattern of corrugation lines, which provide a reference for crystallographic directions. Six of the molecular phases shown were observed for the first time with molecular resolution and the possible two-dimensional arrangements of adenine and uracil molecules for these phases are proposed. The pure adenine and pure uracil structures have chiral unit cells and in the case of pure uracil alternating monochiral domains within the polychiral islands are created. Well-ordered intricate uracil-adenine bimolecular networks were also observed. The self-assembly of both uracil and adenine appears to be weakly influenced by the surface crystallography. The (100) surface of the mineral pyrite (FeS₂) was chosen as the alternative substrate as it is the most common face that occurs naturally in pyrite crystals. The experiments show the formation of small adenine and uracil crystals at the terrace edges. Neither uracil nor adenine were observed to form a monolayer on the surface of the terraces. The results of the experiments described in this thesis are very interesting in terms of establishing the possible mechanisms for creating regular chiral molecular networks and provide a useful insight into the role of surfaces in the processes of self-assembly of RNA bases.
37

Energetic processes driving potential peptide protometabolisms at the origin of living systems / Processus énergétiques gouvernant des protométabolismes peptidiques à l’origine des systèmes vivants

Ajram, Ghinwa 29 November 2018 (has links)
La thèse aborde différentes questions de chimie prébiotique dans le contexte de l’origine de la vie par une approche de chimie systémique. La première partie est dédiée à l’étude de processus d’activation chimique important non seulement pour la formation de polymères, mais aussi pour alimenter le système en énergie de manière à le maintenir dans un état éloigné de l’équilibre, un prérequis pour l’auto-organisation. Il a été suggéré que les intermédiaires 5(4H)-oxazolones formés par l’activation de l’extrémité C-terminale des peptides pourrait être impliquée dans l’auto-organisation du vivant. Dans ce but, nous avons évalué la réactivité de réactifs pertinents dans un contexte prébiotique et décrits dans la littérature comme capables d’activer des acides α-aminés. Aucun d’entre eux n’a manifesté une activité satisfaisante pour l’activation C-terminale des peptides, montrant qu’une voie possible pour alimenter un protométabolisme des peptides en énergie n’est pas identifiée à ce jour à l’exception notable des N-carboxyanhydrides (NCA) qui peuvent être formé par des voies prébiotiquement plausibles. Nous avons par ailleurs démontré que les carbodiimides sont aussi efficaces pour l’activation des N-carbamoylamino acides que pour celle du carboxyle terminal des peptides en milieu aqueux dilué. La seconde partie du document expose de nouveaux résultats en faveur d’un processus de coévolution peptides-nucléotides. D’abord, une étude de la réactivité d’agents d’aminoacylation de l’extrémité 3’ de l’ARN est présentée. Ensuite, nous évaluons des co-polymères acides α-aminés-nucléotides liés par des enchaînements phosphoramidate et esters comme partenaires éventuels de l’évolution chimique. La pertinence cinétique de ces structures est démontrée ainsi que des voies chimiques permettant leur formation. / The thesis addresses several issues in prebiotic chemistry in the context of the origins of life through a systems chemistry approach. The first part is devoted to the study of chemical activation processes that are not only important in the formation of polymers, but also to feed the system with energy in order that a far from equilibrium state is maintained, a prerequisite for self-organization. It has been suggested that 5(4H)-oxazolones intermediates formed by C-terminus peptide activation could be involved in self-organization of life. To this aim, we have checked the reactivity of relevant prebiotic reagents previously proposed to activate α-amino acids. None of them led to a satisfactory C-terminus activation of peptides, showing that no general process for feeding a protometabolism of peptides with energy is identified yet, with the notable exception of N-carboxyanhydrides (NCAs) that can be formed through prebiotically relevant pathways. Additionally, we demonstrated that carbodiimides reagents are as efficient in the activation of N-carbamoyl amino acids as in that of the C-terminus of peptides in diluted aqueous media. The second part of the dissertation discloses new results in support of a process of coevolution of peptides and nucleotides. Firstly, a study of non-enzymatic aminoacylation reagents of the 3’-terminus of RNA is presented. Secondly, we assessed co-polymers of α-amino acids and nucleotides bound by phosphoramidate and ester linkages as potential players in chemical evolution. The kinetic relevance of these structures was demonstrated as well as potential chemical processes that allow their formation.
38

O conceito de protoforma orgânica na determinação da gênese e da natureza do organo-vivente: individuação, forma e vida / The concept of organic protoform in determining of the genesis and nature of the living organism: Individuation, form and life

Santos, Guilherme Francisco 08 August 2017 (has links)
A presente tese se desenvolve por meio da constituição do conceito de protoforma orgânica com o qual objetivamos tratar de relações problemáticas entre as noções gerais de vida e individualidade, particularmente no que se refere ao problema de suas origens, compreendida aqui como o momento privilegiado da gênese organo-vital no qual a tensão entre vida e individualidade se expressa de modo mais evidente. Vida, individualidade e origens se constituem em noções gerais e em grandes temas da investigação e da reflexão filosófica e científica de todos os tempos. O conceito de protoforma orgânica emerge da observação de diversos elementos em um solo histórico-conceitual de investigações científicas e em filosofia natural, que se constitui num conjunto de expressões históricas particulares que investigamos em nossa tese, a saber, os conceitos de monera, de Urschleim e de Urpflanze. Estruturamos o conceito de protoforma orgânica a partir de duas noções-eixo que nortearam o seu sentido. A primeira delas é a noção de uma polaridade entre uma condição pré-individual e uma condição individual como constituinte da forma orgânica. A segunda é a noção de memória orgânica como uma propriedade anímico-psíquica das formas orgânicas universalmente presente, desde os seus níveis mais elementares. Trata-se, assim, de compreender como se dá a relação problemática entre vida e individualidade e como a questão das suas origens pode contribuir para tal compreensão. Assim, o conceito de protoforma orgânica foi estruturado dentro de uma visão morfológica na qual as noções de forma e de orgânico se entrelaçam com as noções de vida e de individualidade. / The present thesis proposes the constitution of the concept of organic protoform with which we aim to deal with problematic relations between the general notions of life and individuality. Particularly with regard to the problem of its origins, understood here as the privileged moment of the genesis of organo-vital beings, at which moment the tension between life and individuality is expressed more clearly. Life, individuality and origins are general notions and themes of research and philosophical and scientific reflection of all time. The concept of organic protoform emerges from the observation of several elements directed to a historical-conceptual soil of scientific investigations and natural philosophy. This basis is constituted by our investigation into a set of particular historical expressions which we investigate in our thesis, namely the concepts of monera, Urschleim and Urpflanze. We structured the concept of organic protoform from two notions-axis that guided its meaning. The first is the notion of a polarity between a preindividual condition and an individual condition as a constituent of the organic form. The second is the notion of organic memory as a psychic property of organic forms universally present, from its most elementary levels. It is therefore a question of understanding how the problematic relationship between life and individuality takes place and how the question of its origins can contribute to this understanding. Thus, the concept of organic protoform was structured within a morphological vision in which the notions of form and of organic intertwine with the notions of life and of individuality.
39

O conceito de protoforma orgânica na determinação da gênese e da natureza do organo-vivente: individuação, forma e vida / The concept of organic protoform in determining of the genesis and nature of the living organism: Individuation, form and life

Guilherme Francisco Santos 08 August 2017 (has links)
A presente tese se desenvolve por meio da constituição do conceito de protoforma orgânica com o qual objetivamos tratar de relações problemáticas entre as noções gerais de vida e individualidade, particularmente no que se refere ao problema de suas origens, compreendida aqui como o momento privilegiado da gênese organo-vital no qual a tensão entre vida e individualidade se expressa de modo mais evidente. Vida, individualidade e origens se constituem em noções gerais e em grandes temas da investigação e da reflexão filosófica e científica de todos os tempos. O conceito de protoforma orgânica emerge da observação de diversos elementos em um solo histórico-conceitual de investigações científicas e em filosofia natural, que se constitui num conjunto de expressões históricas particulares que investigamos em nossa tese, a saber, os conceitos de monera, de Urschleim e de Urpflanze. Estruturamos o conceito de protoforma orgânica a partir de duas noções-eixo que nortearam o seu sentido. A primeira delas é a noção de uma polaridade entre uma condição pré-individual e uma condição individual como constituinte da forma orgânica. A segunda é a noção de memória orgânica como uma propriedade anímico-psíquica das formas orgânicas universalmente presente, desde os seus níveis mais elementares. Trata-se, assim, de compreender como se dá a relação problemática entre vida e individualidade e como a questão das suas origens pode contribuir para tal compreensão. Assim, o conceito de protoforma orgânica foi estruturado dentro de uma visão morfológica na qual as noções de forma e de orgânico se entrelaçam com as noções de vida e de individualidade. / The present thesis proposes the constitution of the concept of organic protoform with which we aim to deal with problematic relations between the general notions of life and individuality. Particularly with regard to the problem of its origins, understood here as the privileged moment of the genesis of organo-vital beings, at which moment the tension between life and individuality is expressed more clearly. Life, individuality and origins are general notions and themes of research and philosophical and scientific reflection of all time. The concept of organic protoform emerges from the observation of several elements directed to a historical-conceptual soil of scientific investigations and natural philosophy. This basis is constituted by our investigation into a set of particular historical expressions which we investigate in our thesis, namely the concepts of monera, Urschleim and Urpflanze. We structured the concept of organic protoform from two notions-axis that guided its meaning. The first is the notion of a polarity between a preindividual condition and an individual condition as a constituent of the organic form. The second is the notion of organic memory as a psychic property of organic forms universally present, from its most elementary levels. It is therefore a question of understanding how the problematic relationship between life and individuality takes place and how the question of its origins can contribute to this understanding. Thus, the concept of organic protoform was structured within a morphological vision in which the notions of form and of organic intertwine with the notions of life and of individuality.
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De la théorie des jeux à l’exobiologie : l’émergence de la coopération comme phénomène critique

Champagne-Ruel, Alexandre 08 1900 (has links)
L’émergence de la complexité, et de la vie en particulier, demeure l’une des énigmes les plus complexes pour la science moderne. Des travaux récents ont souligné la pertinence d’un apport de la physique statistique et de la théorie des phénomènes critiques — et en particulier de la théorie des phénomènes à criticalité auto-régulée — relativement à ces champs d’intérêt, tout autant que du rôle des phénomènes de coopération biochimique dans les premiers instants du vivant. La description des mécanismes par lesquels la vie a pu apparaître est par ailleurs d’un intérêt pratique pour l’astrophysique, puisque notre compréhension de ceux-ci module la manière dont l’analyse de biosignatures s’effectue dans le cadre de la recherche de la vie ailleurs dans l’Univers. L’analyse proposée ici porte sur un modèle en théorie des jeux permettant d’étudier les phénomènes de coopération implémenté dans un contexte spatial servant à émuler la dynamique d’un système ayant pu voir apparaître la vie. Une analyse de l’espace des paramètres du modèle révèle que celui-ci affiche des phénomènes de transition de phase et d’auto-organisation de structures spatiales, ces éléments se révélant des adjuvants à l’émergence de la coopération entre joueurs a priori égoïstes, dans un contexte qui à prime abord n’est pas d’emblée favorable à l’apparition de comportements coopératifs. Les résultats obtenus ici semblent supporter que la coopération biochimique puisse apparaître via un phénomène de transition de phase et que le modèle sous-jacent de dilemme du prisonnier itéré sur réseau présenté ici agit comme un système à criticalité autorégulée. / The emergence of complexity, and of life more specifically, is still one of the most intractable conundrums for modern science. Recent work emphasized the relevance of statistical physics and critical phenomena theory’s contribution to those questions — especially of self-organized criticality theory — just as much as the role of biochemical cooperation in life’s first moments. Moreover, the description of the mechanisms by which life could have appeared is of particular interest for astrophysics, because our comprehension of those mechanisms influences how biosignatures are analyzed in the context of the search for life elsewhere in the Universe. The analysis presented here concerns a model in game theory that allows to study cooperation phenomena — implemented in spatial context as to emulate the dynamics of a system in which life could have appeared. An analysis of the model’s parameter space reveals that it displays phase transition and self-organization of spatial structures phenomenon, those elements being adjuvants to the emergence of cooperation between a priori egoist players, in a context that is initially not favorable to the emergence of cooperative behavior. The results obtained here thus seem to support the idea that both biochemical cooperation can emerge through phase transition phenomena, and that the underlying lattice iterated prisoner’s dilemma model used here behaves like a self-organized critical system.

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