Orientador: Ivanira Jose Bechara / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T09:34:23Z (GMT). No. of bitstreams: 1 Bockelmann_PetraKarla_D.pdf: 29179947 bytes, checksum: 8c02cdd38976a29e54d61610a6bfd9fe (MD5) Previous issue date: 2008 / Resumo: As nadadeiras caudais de teleósteos, quando parcialmente amputadas, passam por um rápido processo de regeneração chamado de regeneração epimórfica, caracterizado pela formação de uma massa de células indiferenciadas, diferenciação dessas células, síntese e deposição de matriz extracelular e restauração morfológica. A regeneração da nadadeira é extremamente sensível a fatores físicos e químicos externos, tais como variações na temperatura, intensidade da luz, ação de alguns agentes contaminantes ambientais e ação de algumas drogas que podem interferir na capacidade regenerativa das nadadeiras dos peixes teleósteos. Existem relatos na literatura, que drogas anti-inflamatórias não esteróides, podem interferir de alguma forma na restauração tecidual de diversos organismos, uma vez que inibem a ação da enzima ciclooxigenase e, conseqüentemente, a conversão do ácido araquidônico em prostaglandina, elementos que desempenham funções importantes na proteção celular, crescimento, angiogênese e produção de matriz extracelular. Em vista disso, este trabalho teve como objetivo avaliar os efeitos de drogas antiinflamatórias não esteróides, naproxeno e indometacina, durante o processo regenerativo da nadadeira caudal de peixe teleósteo Cyprinus carpio (carpa). Para isso, foram montados experimentos com cinco grupos: grupo formado com peixes que serviram como controle, grupo formado com peixes que entraram em contato com o naproxeno, na dose de 15,6 mg/L, e três grupos formados por peixes que tiveram contato com a indometacina nas doses 10, 20 e 30 mg/L cada. Os peixes foram anestesiados e suas nadadeiras caudais foram amputadas transversalmente e, após a amputação os peixes foram divididos entre os cinco grupos e permaneceram nos aquários até que a regeneração ocorresse. Os animais foram anestesiados, sacrificados e as nadadeiras em regeneração foram excisadas e fixadas em intervalos de 1, 2, 4, 5, 6, 8, 10 e 12 dias após a amputação. As amostras foram processadas para permitir uma análise histoquímica, ultra-estrutural e morfométrica das possíveis alterações no processo regenerativo da nadadeira caudal de teleósteo em contato com as drogas em questão. Os grupos tratados com o naproxeno e a indometacina utilizada na dose de 10 mg/L apresentaram o processo de regeneração de forma semelhante ao grupo controle, ou seja, não afetaram a formação da capa epidermal, a formação do blastema, a diferenciação das células blastemais, bem como a síntese, deposição, organização e mineralização dos componentes da matriz lepidotriquial e a síntese das actinotriquias durante o processo regenerativo da nadadeira caudal. No entanto, os peixes tratados com a indometacina nas doses de 20 e 30 mg/L apresentaram um atraso no processo de regeneração da lepidotriquia e da actinotriquia quando comparados com os peixes do grupo controle. Estudos mais detalhados sobre os mecanismos de ação das drogas anti-inflamatórias não esteróides e a ação dessas drogas sob a expressão ou a inibição da expressão de alguns genes envolvidos no processo de regeneração da nadadeira caudal de teleósteo talvez possam responder a razão das diferenças de efeitos entre essas duas drogas / Abstract: The fins of teleosts, when partially amputated, they pass for a quick regenerative process called epimorphic regeneration, characterized by the formation of a mass of undifferentiated cells, by the differentiation of these cells, by the synthesis and the deposition of the extracellular matrix and morphological restoration. The regeneration of the fin is extremely sensitive to external physical and chemical factors such as temperature variations, light intensity, the action of some environmental contaminants and the action of some drugs that can interfere in the regenerative capacity of teleost fins. There are some studies that show that nonsteroids anti-inflammatory drugs can interfere somehow in the tissue restoration of many organisms, as they inhibit the action of ciclooxygenase enzyme and, consequently, the conversion of arachidonic acid in prostaglandins, elements that execute important roles in cell protection, growth, angiogenesis and in the production of extracellular matrix. In this sense, this study aimed to evaluate the effects of nonsteroid anti-inflammatory drugs, naproxen and indomethacin, during the regenerative process of the teleost tail fin Cyprinus carpio (carp). Therefore, experiments were undertaken in five groups: the control group fish, group of fish in touch with naproxen in doses of 15.6 mg/L, and three groups of fish in contact with indomethacin in doses of 10, 20 and 30 mg/L each. The fish were anesthetized and their fins transversally amputated and, after amputations the fish were divided among the five groups described above and were left in the aquaria until the occurrence of regeneration. The animals were anesthetized, sacrificed and the regenerating fins excised and fixed in intervals of 1, 2, 4, 5, 6, 8, 10 and 12 days after amputation. The samples were processed in order to permit a histochemical, ultra-structural and morphometric analysis of the possible alterations in the regenerative process of the tail fin of the teleosts in contact with the drugs mentioned above. The group treated with naproxen and indomethacin in a 10 mg/L dose showed a regenerative process similar to the control group, thus, it did not affect the formation of the epidermal layer, the formation of blastema, and the differentiation of blastemal cells, as well as its synthesis, deposition, organization and mineralization of the lepidotrichial matrix and the synthesis of actinotrichia during the process of regeneration of the tail fin. However, the fish treated with indomethacin in doses of 20 and 30 mg/L presented a delay in the regenerative process of the lepidotrichia and actinotrichia when compared to the control group fish. Detailed studies about the mechanisms of nonsteroids anti-inflammatory drugs action and the action of these drugs under the expression or inhibition of expression of some genes involved in the teleost tail fin regenerative process could explain more precisely the reason of the differences of effect between these two drugs / Doutorado / Histologia / Doutor em Biologia Celular e Estrutural

La formation des analystes, articulant le problème thérapeutique des modes de résolution de la cure aux questions collectives de garantie et d’enseignement, pose avec acuité la question des conditions de transmission et de formation propres au champ de la psychopathologie. La thèse s’attache d'une part à expliciter les fondements de la question et les conséquences Cliniques et institutionnelles des options à cet endroit; d'autre part, à rendre compte de la cohérence interne et spécifique des modes de transmission de la psychanalyse, dans la voie épistémologique ouverte par Lacan, dont la « Proposition d’Octobre sur le psychanalyste de ’Ecole » est ici le texte de référence. / The training of the psychoanalysts, articulating the therapeutic problem of the modes of resolution of the cure in the collective questions of guarantee and teaching, pose with acuteness the question of the conditions of transmission and training appropriate to the psychopathology. The thesis attempts on one hand to clarify the foundations of the questionand the clinical and institutional consequences of the options ; on the other hand, to report the internal and specific coherence of the modes of transmission of the psychoanalysis, in the epistemological way opened by Lacan, Whose is here the reference text. In the epistemological way opened by Lacan, whose « Proposition d’Octobre sur le psychanalyste de l’Ecole » is here the reference text.

La question de la fin de vie et du processus de deuil qui s’ensuit pour le proche du défunt reste toujours d’actualité tant elle comporte d’énigmes. Comment pouvons-nous penser que le travail du deuil puisse être facilité ? La présente recherche a pour objectif d’étudier, en appui sur les travaux et les théories de D. W. Winnicott, comment le soin peut être transitionnel dans la relation et dans l’espace intersubjectif créé par la triade composée du soignant, du patient et du «proche-tiers». A partir d’un échantillon de 30 patients, les entretiens semi-directifs de 21 soignants et de 8 proches ont été analysés. Cette analyse nous permet de montrer de quelle manière le soin est transitionnel dans l’accompagnement. Elle nous montre également quels bénéfices peut avoir l’accompagnement en fin de vie, d’une part pour le patient dans l’ici et maintenant de sa fin de vie, d’autre part, pour le soignant dans l’ici et maintenant de l’accompagnement proposé mais aussi dans «l’après-coup» pour les autres accompagnements qu’il pourra proposer. Enfin, un troisième bénéfice certain est pour le «proche-tiers» dans l’ici et maintenant de l’accompagnement de son proche malade mais également par la suite dans la conduite du deuil. / Questions revolving around end of life and the grieving process that follows for loved ones are as relevant as they are puzzling. Is it unrealistic to think that mourning can be facilitated? This research aims to examine and build upon the work and theories of D. W. Winnicott. This research delves into how care may be transitional in the relationship and in the intersubjective space created by a triad of care: medical caregiver(s), patient and loved ones. From a sample of 30 patients, semi-structured interviews with 21 medical caregivers and 8 relatives were analyzed. This analysis shows how the care is transitional in the accompaniment. This research reveals the benefits of creating a transitional space during end of life care. First and foremost, it assists the patient in the here and the now of end of life; it, then, aids the caregivers. Medical caregivers and loved ones alike benefited from accompanying the patients in death both during the palliative care stages as well as afterwards as they worked through the grieving process.

The topic of this thesis is the gothic fiction of Selma Lagerlöf. Its primary purpose is to investigate how Lagerlöf's work can be understood in relation to the gothic genre; what particular themes, motifs and formal aspects appear when making this connection and how they can be interpreted, as well as which literary and cultural contexts become relevant. The study is based on close readings of six short stories that, in comparison, appear to be some of the most gloomy and horrific in her production: "Karln. En julsägen" (1891), "De fågelfrie", "Stenkumlet", "Riddardottern och havsmannen" (1892), "Spökhanden" (1898) and "Frid på jorden" (1917). The gothic was an important feature of the literature of the last decade of the nineteenth century, when Lagerlöf made her debut. Therefore one of the main purposes of this study is to highlight her as one of the key writers of gothic fiction in Sweden by the time. In this context the gothic might be considered as closely related to the currents of decadence and fin-de-siècle. However, the gothic continued to be an important element throughout Lagerlöf's production, and this is illustrated by the inclusion of a story from a later period among the primary sources. The gothic genre can be defined by certain themes and motifs, but also by its narrative strategies. The analyses of the six stories show how themes and composition are used to create an atmosphere of fear and darkness, but also, more importantly, to create a sense of ambiguity. The study also discusses the relationship between the gothic and the fantastic and special attention is paid to aspects such as the hesitation concerning how to interpret the supernatural, as well as the fragmentary bodies and psyches of the stories. The main themes of the six stories can be summarized as dealing with the haunting and return of the past, as well as the fear associated with the transgression of limits - between fantasy and reality, the civilized and the primitive, life and death and self and other. Central to the argument in this study is das Unheimliche - the uncanny - a concept that links a certain kind of fear to uncertainty, doubles, ghostliness and haunting. Sigmund Freud has described it as a paradox, as something terrifyingly strange and yet familiar at the same time. The gothic reproduces the experience of reality expressed by this concept - a sense that the self is the source of horror and that identity is something highly unstable.

The Financial Accounting Standards Board (FASB) issued Interpretation No. 46 (FIN 46), Consolidation of Variable Interest Entities – An Interpretation of ARB No. 51, in January 2003 and revised it in December 2003, with the objective to improve the transparency of financial information. Under FIN 46, companies are required to consolidate variable interest entities (VIEs) on financial statements if they are the primary beneficiaries of the VIEs. This dissertation empirically examines whether the implementation of this new financial reporting guidance affects firms’ accruals quality and investment efficiency. A manually collected sample comprised of firms affected by FIN 46 and firms disclosing no material impact from FIN 46 is used in the empirical analyses.The first part of the dissertation investigates the effects of FIN 46 on accruals quality. By using different accrual quality measures in prior studies, this study found that firms affected by FIN 46 experienced a decrease in accrual quality compared to firms reporting no material impact from FIN 46. Among the firms affected by FIN 46, firms consolidating VIEs were compared with firms terminating or restructuring VIEs. The accruals quality of firms consolidating VIEs was found to be lower than that of firms terminating or restructuring VIEs. These results are consistent in tests using alternative control samples.The second part of this dissertation examines the effects of FIN 46 on investment efficiency. Mixed results were found from using two different proxies used in prior literature. Using the investment-cash flow sensitivity to proxy for investment efficiency, firms affected by FIN 46 experienced a decrease in investment efficiency compared to firms reporting no material impact. It was also found that higher investment-cash flow sensitivity for firms consolidating VIEs during post-FIN 46 periods compared to both the no-impact firms and the matched pair control sample. Contrasting results were found when the deviation from expected investment is used as another proxy for investment efficiency. Empirical analyses show that FIN 46 firms experienced improved investment efficiency measured by the deviation from expected investment after their adoption of FIN 46. This study also provides explanations for the opposite results from the two different proxies.

Aluminum and aluminum-alumina powder mixtures were used to produce pyramidal fin arrays on aluminum substrates using cold spray as an additive manufacturing process. Using aluminum-alumina mixtures instead of pure aluminum powder could be seen as a cost-effective measure, preventing nozzle clogging. The fin geometries that were produced were observed using a 3D digital microscope to determine the flow passages width and fins geometric details. Heat transfer and pressure tests were carried out using different ranges of appropriate Reynolds numbers for the sought commercial application to compare each fin array and determine the effect of alumina content. It was found that the presence of alumina reduces the fins’ performance when compared to pure aluminum but that they still outperform traditional fins. Numerical simulations were performed and were used to explain the obtained experimental results. The numerical model opens up new avenues in predicting different parameters such as pressure and substrate temperature.

Ce travail a pour objectif d’étudier certaines représentations – écrites et imagées – des exécutions capitales en France, dans la seconde moitié du XVIe siècle et les premières décennies du XVIIe siècle. Ces exécutions sont nombreuses à une époque marquée par d’importants troubles politiques et religieux. Elles ont lieu en place publique, se veulent édifiantes et exemplaires pour les spectateurs, et affirment l’autorité du souverain, qui restaure l’ordre dans le royaume. Cette étude s’organise autour des trois figures fondamentales de la punition : le roi, le peuple et le condamné. La punition entretient toujours un lien très étroit avec l’autorité qui châtie. Nous verrons que les réflexions de Foucault autour du supplice se vérifient dans certaines sources, mais que les écrits et les images ne font pas obligatoirement de ce spectacle une affirmation de l’autorité royale, ni de la justice divine, parfois problématiques. Dans les sources écrites, les spectateurs réagissent souvent à l’exécution capitale, et il arrive que les auteurs expliquent les violences populaires dans un cadre extra-judiciaire, comme une tentative de rétablir l’ordre et la justice. Le condamné, lui, est à la fois « acteur » du supplice par son comportement sur l’échafaud et « victime ». Un certain nombre de constantes se dégage de la représentation du condamné, liées à son sexe et son âge, à la religion des auteurs et aux types de textes et d’images dans lesquels il est dépeint. Ce travail, qui envisage des contextes politiques et religieux différents et compare des sources très diverses, entend montrer que la littérature et l’iconographie construisent une image complexe du spectacle de l’exécution capitale, en particulier à travers les motifs de l’ordre et du désordre qui les traversent.

Les matériaux biocomposites, en particulier les composites matrice thermoplastique biosourcée ou non renforcée de charges ou de fibres végétales, connaissent actuellement un essor significatif et présentent pour l'avenir un gisement grandissant de matières en fin de vie. En conséquence, l'étude du comportement de ces matériaux au regard de différents scénarios de fin de vie que sont le recyclage mécanique, le compostage et l'incinération constitue un enjeu scientifique et technologique important. Le premier objectif de cette thèse est d'étudier la fin de vie par retransformation (cycles successifs d'injection et de broyage) de biocomposites à matrice polypropylène (PP) chargé de farine de bois. L'impact de la taille des particules de bois et d'un agent de couplage a été évalué. Une très bonne stabilité mécanique jusqu'à 7 cycles de retransformation a été observée malgré des dégradations des différents composants du matériau. Le comportement face à la retransformation après vieillissement artificiel accéléré ou après une exposition naturelle en extérieur a été étudié. La tendance majeure dégagée est un phénomène de « régénération » des propriétés mécaniques par retransformation, et cela malgré des dégradations importantes après vieillissement. Il a été également été observé que l'ajout de bois a tendance à limiter la photodégradation du PP. Le second objectif est d'étudier la fin de vie de biocomposites à matrice acide polylactique (PLA) renforcé de fibres de lin. L'impact de différents paramètres de formulation, de la technique de mise en œuvre et d'un vieillissement hygrothermique sur la retransformation de ces matériaux a été évalué. Les mêmes phénomènes de « régénération » sont observés, ce qui montre l'effet bénéfique de la retransformation. La fin de vie par compostage et par biodégradation est traitée. Des mesures d'énergies de combustion ont enfin permis d'estimer le potentiel de valorisation par incinération qui serait en lien avec le niveau de dégradation du PLA. / Nowadays, biocomposite materials are booming and will be a growing end-of-life issue for the future. They are based on a thermoplastic matrix (oil-based or bio-based) reinforced with vegetable fillers or fibers. Consequently, the study of their end of life through recycling, composting and incineration is a scientific and technologic challenge.The first goal of this thesis is to study the reprocessing end of life (successive injection and grinding cycles) of polypropylene (PP) based biocomposites filled with wood flour. The impact of the wood particle size and a coupling agent was assessed. Thus, a very good mechanical stability was observed up to 7 reprocessing cycles despite some degradation from the material components. Then, the reprocessing after artificial or natural UV weathering was carried out. The major trend is a “regeneration” phenomenon of mechanical properties after reprocessing in spite of strong degradations after UV weathering. Moreover, the addition of wood filler tends to restrain the PP photochemical degradation.The second goal is to study the end of life of polylactic acid (PLA) based biocomposites reinforced with flax fibers. The impact of the composition, the processing technic and humidity weathering on the reprocessing was assessed. Similar “regeneration” phenomena were observed leading to conclude to the beneficial effect of reprocessing. Then composting and biodegradation aspects were investigated. Heat release rate measurements enabled to estimate the incineration potential which could be linked to the PLA degradation rate.

Ce mémoire porte sur le développement d'un protocole d'extraction sélective de métaux présents dans les accumulateurs Ni-Cd en fin de vie. Classiquement, les procédés hydrométallurgiques appliqués à ce type de solides comportent de nombreuses étapes dont les principales sont la lixiviation et la récupération du métal par électrolyse. Le procédé utilisé permet le couplage des opérations d'Electrolixiviation et d'Electrodéposition (noté E/E) au sein d'une même cellule. La technique est basée sur la lixiviation de la matière active des accumulateurs Ni-Cd par les protons générés à l'anode, les cations lixiviés (Co2+, Ni2+ et Cd2+) migrent vers la cathode où le cadmium est sélectivement réduit. Nous avons étudié les possibilités de récupération des métaux, mais également tenté d'appréhender les phénomènes prenant place dans la cellule lors du couplage E/E. Dans un premier temps, nous avons choisi de démanteler manuellement des accumulateurs en raison de la complexité des broyats industriels. La matière active des accumulateurs Ni-Cd a été caractérisée. Sa composition moyenne est la suivante :Cd(OH)2 : 45,3 %, Cd0 : 0,02 %, Ni(OH)2 : 30,0 %, Ni0 :12,9 %, NiOOH : 0,9%, Co(OH)2 : 2,4 %. Au vu des différentes formes minéralogiques présentes, ce solide peut être considéré comme un déchet modèle pour ce traitement. Avant d'envisager le couplage E/E, la lixiviation chimique de la matière active par H2SO4 a d'abord été étudiée. La modélisation de cette opération a mis en évidence que la cinétique de dissolution de Cd(OH)2 est gouvernée par le transfert de masse des protons, la dissolution de Ni(OH)2 et Co(OH)2 étant quant à elle régie par la réaction chimique de surface. Dans ces conditions de lixiviation douce, le nickel métallique n'est pas oxydé et se retrouve dans le résidu solide avec le carbone. Nous avons pu démontrer ensuite la sélectivité de l'électrodéposition vis-à-vis du Co2+ et du Ni2+ avec un rendement faradique d'environ 99 % à une densité de courant de 350 A.m-2. L'étude cinétique de l'E/E a montré que l'électrolixiviation est l'étape limitante du procédé, phénomène qui a également été modélisé. L'E/E appliquée aux matériaux d'électrodes permet en 5 h 30 de lixivier 97 % du cadmium initialement présent. Le solide résiduel est composé à 82 % de nickel, principalement sous la forme métallique, 4 % de cadmium, 0,5 % de cobalt et 3 % de carbone. Le dépôt de cadmium est obtenu avec une pureté supérieure à 97 % et un rendement faradique de déposition supérieur à 74 % à une densité de courant de 350 A.m-2. La faisabilité du couplage E/E appliqué au traitement d'accumulateurs Ni-Cd en fin de vie a été démontrée malgré la complexité de la matrice. Les premiers essais d'application de ce traitement à des échantillons industriels (Cd(OH)2 : 36,1 %, Ni(OH)2 : 24,1 %, Ni0 : 16,6 %, NiOOH : 5,5 %, Co(OH)2 : 2,4 % et Fe :1% en masse) confirment les résultats obtenus avec les matériaux d'électrodes provenant du démantèlement manuel / This thesis focuses on the development of a protocol for selective extraction of metals from spent Ni-Cd batteries. Conventionally, hydrometallurgical processes applied to this type of solids involve several steps, the main ones being the leaching and the metal recovery by electrolysis. The method used consists in coupling Electroleaching to Electrodeposition operation (denoted E/E) within the same cell. The technique is based on the leaching of the active material of Ni-Cd batteries by protons generated at the anode: the cations (Co2+, Ni2+ and Cd2+) released by leaching migrate to the cathode where the cadmium is selectively reduced. We studied the possibility of metals recovery, but also tried to understand the phenomena occurring in the cell during the E/E experiments. Initially, it was preferred to manually dismantle batteries due to the complexity of industrial waste crushed. The active matter of Ni-Cd has been characterized. Its average composition is as follows: Cd(OH)2: 45.3%, Cd0: 0.02%, Ni(OH)2: 30.0%, Ni0: 12.9%, NiOOH: 0.9%, Co(OH)2: 2.4%. In view of these different mineralogical forms, this solid can be considered a model for the waste treatment. Before considering the E/E treatment, chemical leaching of the active matter by H2SO4 was first studied. Modelling of the tests carried out showed that the kinetics of Cd(OH)2 dissolution is governed by mass transfer of protons and the dissolution of Ni(OH)2 and Co(OH)2 by the surface chemical reaction. Under these conditions of soft leaching, metal nickel is not oxidized and is found in the solid residue, with carbon. We had to demonstrate the cadmium electrowinning selectivity, for separation from Co2+ and Ni2+ species, with a current efficiency up to 99% at a current density of 350 A.m-2. The kinetic study of the E/E showed that electroleaching is mainly governed by H+ generation at the anode. Besides, the overall process is largerly controlled by cations transport from the anode to the cathode side: this transport phenomenon had also been modeled. The E/E applied to the electrode materials for 5 h 30 allows the leaching of 97% of the cadmium initially present. The residual solid is composed by 82% of nickel, mainly in the metallic form, 4% of cadmium, 0.5% of cobalt and 3% carbon. The deposition of cadmium is obtained with a purity greater than 97% and a current efficiency greater than 74% at a current density of 350 A.m-2. The feasibility of the E/E coupling applied to the spent Ni-Cd batteries treatment has been demonstrated despite the complexity of the matrix. The first tests to apply this treatment to industrial samples (Cd(OH)2: 36.1% Ni(OH)2: 24.1% Ni0: 16.6% NiOOH: 5.5% Co(OH)2: 2.4% and Fe: 1% by weight) confirm the results obtained with the electrode material from the manual dismantling

The palaeoenvironment from which early tetrapods emerged is crucial to comprehend in order to understand the mechanisms that drove and allowed the terrestrialization of vertebrates; one of the most important evolutionary ‘events’ in the history of animals. Nevertheless, much of the terrestrialization is shrouded in obscurity, inter alia, due to scarcity of early tetrapods in the fossil record. Each new discovery of anything linked to vertebrate terrestrialization is therefore of great importance. Here, I present new detailed analyses of the palaeoenvironmental conditions at the time of formation of the earliest (early Middle Devonian) tetrapod trackways found in the Zachełmie Quarry in the Holy Cross Mountains of southern Poland. The trackways are found in three horizons in a clay-rich dolomitic succession represented by the Lower Complex of the Wojciechowice Formation. This Lower Complex is composed of short shallowing upward sequences that often terminate with desiccation cracks and/or paleosols. Vertically fluctuating δ18O values in the complex suggest multiple episodes of closed hydrological systems. A model of ephemeral to perennial lakes in a terrestrial setting is therefore proposed. Such environment is in concordance with evidence of scarce bioturbation and a flourish of microbial communities that, in contrast to a normal marine setting, most likely represent an ecologically stressed ecosystem. Furthermore: non-marine rare earth element (REE) signals, desiccation events, fossils of green algae (charophytes), paleosol development, low energy cyclic deposits and general lack of marine taxa in the body and trace fossil records in this complex firmly establishes the interpretation of palustrine carbonates formed in a lacustrine-like setting. However, in the lower part of the complex, some highly fractioned marine fossils occur. These are suggested to have been transported during wash-up events which temporally places the setting in marine proximity. Seasons of monsoonal rainfall resulted in erosion and influx of detrital grains which is evidenced by fine planar lamination (of seasonal cyclicity) in most of the sediments and occasional occurrence of blackened clasts (and rain-drop imprints). Thus, none of the pre-existing palaeoenvironmental hypotheses of tetrapod emergence are in full concordance with the data from the Zachełmie Quarry. Instead, a new palaeoenvironment is proposed for the earliest tetrapods: schizohaline ephermal to perennial lakes with periodic desiccation. This infers that already in the early Middle Devonian, tetrapods had conquered the terrestrial realm and were perhaps already capable of terrestrial locomotion over quite substantial distances. / Däggdjur, reptiler, fåglar och amfibier utgör tillsammans en besläktad djurgrupp som kallas för tetrapoder (fyrfotingar). Deras gemensamma förfader härstammade från de lobfenade fiskarna men skiljde sig från dem genom att inneha utvecklade ben med tår istället för de ”köttiga” fenor som de lobfeniga fiskarna karaktäriseras av. Denna evolutionära nyhet tillät, tillsammans med en rad andra egenskaper (lungor, skydd för uttorkning av dermis etc.), att vertebrater helt och hållet kunde koloni-sera land. I och med att vår egen existens är en direkt följd av denna evolutionära händelse är detta ett hett forskningsämne inom evolutionsbiologin. Ändå är mycket fortfarande höljt i dunkel beträffande hur koloniseringen av land gick till och vad det var som drev denna utveckling eftersom övergången skedde under en, i geologisk mått, snabb tidsrymd. Dock har de sista årtiondena resulterat i flertalet nya fossilfynd av primitiva tetrapoder. Ett fynd som är speciellt spektakulärt eftersom det är den hittills äldsta efterlämningen av tetrapoder, är fotspår som uppenbart är gjorda av ett djur som hade ben och tår istället för fenor. Detta förvånade hela det vetenskapliga samfundet eftersom det innebar att vi (tetrapoderna) utvecklades tidigare än vad som var dittills trott och att vertebrat-koloniseringen av land förmodligen skedde flertalet miljoner år tidigare. Vad som också skiljer ett spårfossil från andra fossil är att de är spår av djuren från när och där de levde till skillnad från bara deras skelettdelar som oftast transporterats från där de dog och bara preserveras i speciella miljöer. Detta har jag utnyttjat i detta arbete för att försöka avgöra i vilken miljö de är avsatta i. Jag har analyserat de sedimentära bergarterna i stenbrottet i södra Polen med skärningen som innehåller de lagren i vilka fotspåren finns. Analyser av sällsynta jordartsmetaller från de tre lager där fotspår är tydliga, antyder en speciell avsättningsmiljö som inte liknar en typisk havsmiljö. I den undre delen av lagerföljden där de spårbärande lagren påträffats finns återkristalliserade saltkristaller, torkningssprickor och fossila jordar som indikerar korta respektive långvariga perioder av uttorkning. Andra fossil som i en normal marin miljö borde bevaras i en dolomitisk kalksten lyser med sin frånvaro och istället påfinns massiv koloni-sering av cyanobakterier. Detta brukar ske i speciella miljöer som avviker från vanlig marin komposi-tion, så som äldre sötvattensmiljöer eller laguner med hög salthalt, som därmed är ”svårbebodd” för djur som annars livnär sig på de fotosyntiserande bakterierna. Implikationen av mitt arbete är att tetrapoderna redan i tidig mellan Devon (ca 390 miljoner år sedan) inte bara hade utvecklat ben utan också att de kunde använda dem över landsträckor för att ta sig till, och mellan, kontinentala vatten. Detta är ännu en viktig pusselbit i pusslet som ämnar rekonstruera tetrapodernas (och vår egen) uppkomst.