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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.
81

Estudos estruturais em órgãos reprodutivos de Tapirira guianensis Aubl. (Anacardiaceae) / Structural studies on the reproductive organs of Tapirira guianensis Aubl. (Anacardiaceae)

Tölke, Elisabeth Emília Augusta Dantas, 1984- 05 July 2013 (has links)
Orientadores: Sandra Maria Carmello Guerreiro, Silvia Rodrigues Machado / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T04:49:10Z (GMT). No. of bitstreams: 1 Tolke_ElisabethEmiliaAugustaDantas_M.pdf: 15837739 bytes, checksum: 8d91bccef86d47cf61ace6595cbf206b (MD5) Previous issue date: 2013 / Resumo: Tapirira guianensis Aubl. (Anacardiaceae) conhecida popularmente como pau-pombo é uma espécie importante para uso madeireiro, medicinal e pode ser empregada na recuperação de áreas degradadas e de matas ciliares. Diversas substâncias são produzidas em estruturas secretoras específicas, sendo a presença de canais e cavidades secretoras característica universal da família. Na literatura é relatada a presença de disco nectarífero intraestaminal nas flores de muitas Anacardiaceae. No entanto, estudos anatômicos e histoquímicos recentes não comprovaram a secreção de néctar por esta estrutura. Além disso, nestes trabalhos foi verificada a persistência do disco intraestaminal no fruto maduro de T. guianensis, bem como a presença de um endocarpo secretor em frutos não maduros. Aliado a estes fatores, a ontogenia de frutos e sementes também é um tema pouco explorado frente ao grande número de espécies da família. A anatomia dos frutos de Anacardiaceae tem-se mostrado de grande valor sistemático. Assim, o presente trabalho consistiu em verificar a estrutura e ultraestrutura do disco glandular de flores e frutos de T. guianensis, bem como examinar a natureza da secreção produzida e estudar a ontogenia do fruto e da semente. Com os resultados alcançados foi possível determinar que a glândula floral das flores hermafroditas de T. guianensis é uma glândula de secreção mista, produzindo néctar com predominância de sacarose, lipídios e substâncias fenólicas. Ultraestruturalmente esta glândula passa por mudanças profundas ao longo do desenvolvimento da flor, inicialmente rica em amiloplastos e posteriormente plastídios desprovidos de amido e mitocôndrias repletas de gotículas de óleo, indicando a mudança da secreção antes predominantemente hidrofílica para lipofílica. No que diz respeito à anatomia do fruto, observou-se que o mesmo possui características típicas da tribo Spondieae, porém algumas delas indicam uma condição menos derivada da espécie, como ausência de opérculo e endocarpo relativamente fino quando comparado com outras espécies da mesma tribo. O pericarpo possui grande quantidade de canais resiníferos na região do mesocarpo, epicarpo produzindo substâncias fenólicas e lipídios, e por meio de microscopia eletrônica de transmissão pôde-se observar o modo de secreção, as organelas envolvidas do processo, bem como a estrutura celular. A semente provém de um óvulo único, anátropo, bitegumentado, crassinucelado de funículo longo. A semente não possui camada mecânica, tem a exotesta e endotégmen ricos em substâncias fenólicas, cristais no mesotégmen, desenvolvimento de paquicalaza parcial, hipóstase fenólica e lipídica, permanência de funículo aderido ao envoltório da semente, formando um arilo vestigial. O embrião armazena grande quantidade de proteínas e amido, indicando uma condição de transição da espécie, pois em Anacardiaceae as reservas são constituídas principalmente por proteínas e lipídios. O fruto e semente apresentaram algumas características anatômicas possivelmente relacionadas à dispersão como, formação de aerênquima no mesocarpo interno e na mesotesta, acúmulo de amido no mesocarpo. O trabalho traz contribuições no estudo de glândulas florais em Anacardiaceae e na área de ontogenia de frutos e sementes / Abstract: Tapirira guianensis Aubl. (Anacardiaceae) well-known as "pau-pombo" is an important species with uses as timber, in medicine and can be employed recovering degraded areas and riparian forests. Several substances are produced in specific secretory structures and the presence of cavities and ducts are universal features in the family. In literature is reported the presence of an intrastaminal receptacular nectary in the flowers of many Anacardiaceae, however anatomical and histochemical recent studies did not support the nectar secretion by this structure. Furthermore, in other studies were found the persistence of intrastaminal receptacular gland in T. guianensis ripe fruits and the presence of a secretory endocarp in unripe fruits. Allied these factors, the ontogeny of fruits and seeds is also a relatively unexplored subject, in contrast with the large number of species from this family. The fruit anatomy of Anacardiaceae has proved great systematic value. Thus, the present study verified T. guianensis structure and ultrastructure of flowers and fruits intrastaminal gland and examined the nature of substances produced as well the fruit and seed development. With the results obtained it was possible provide that the T. guianensis floral gland of hermaphrodite flowers is a mixed secretion gland, producing nectar with sucrose predominance, lipids and fenolic substances. Ultrastructurally, this gland undergoes deep changes during the development of the flower, originally rich in amyloplasts and subsequently chloroplasts devoids of starch and mitochondria replete with oil droplets, indicating the change in the secretion predominantly hydrophilic to lipophilic. With respect to the fruit anatomy, it was observed characteristics typical of the tribe Spodieae, but some of them indicate a condition less derived of this species, such as lack of operculum and endocarp relatively thin compared to other species of the same tribe. Pericarp has a large number of resiniferous ducts in mesocarp region, and epicarp produces phenolic substances and lipids. By transmission electron microscopy it was possible to observe the way of secretion, the organelles involved in process and the cell structure. Seed comes from a single ovule, anatropous, bitegmic, crassinucelate with longe funicle. Seed does not have mechanical layer, has exotest and endotegmen rich in phenolic substances, crystals in mesotegmen, development of partial pachycalaza, phenolic and lipid hypostasis, permanence of the funicle attached to the seed-coat, forming a vestigial aril. The embryo stores large amounts of protein and starch, indicating a transitional condition in the species, because Anacardiaceae reserves comprehend mainly protein and lipids. Fruit and seed showed anatomical characteristics possibly related to dispersion, like formation of aerenchyma in the inner mesocarp and mesotest, starch accumulations in mesocarp. The work brings contributions in the study of Anacardiaceae floral glands and in the area of fruit and seeds ontogeny / Mestrado / Biologia Vegetal / Mestra em Biologia Vegetal
82

O desenvolvimento embrionário da Piapara - Leporinus elongatus (Pisces, Anostomidae) utilizando marcadores ósseos / Embryonic development of piapara - Leporinus elongatus (Pisces, Anostomidae) using bone markers

Erika Zolcsak de Sousa 21 May 2014 (has links)
O conhecimento dos estágios iniciais do desenvolvimento embrionário de peixes é de extrema importância para o estudo de espécies nativas com potencial para a piscicultura, uma vez que permite o estabelecimento de diretrizes para a criação destes animais. Este projeto estudou o desenvolvimento embrionário da piapara (Leporinus elongatus), um peixe de grande importância na pesca esportiva e profissional na bacia dos rios Pardo e Jequitinhonha, visando compreender as fases desse animal em diversos estágios de desenvolvimento, utilizando marcadores ósseos que possibilitaram visualizar o desenvolvimento ósseo da espécie. As Proteínas Ósseas Morfogenéticas (BMP-2 e BMP-4) são consideradas moléculas essenciais reguladoras no desenvolvimento embrionário e na formação óssea, sendo ainda pouco estudadas em peixes; tais proteínas puderam ser observadas apenas no estádio larval até o período juvenil, não sendo evidenciadas nos estágios anteriores. Foram utilizadas também técnicas de Microscopia Eletrônica de Varredura e histológicas, onde foi possível visualizar as fases principais do desenvolvimento embrionário, entre elas, clivagens, diferenciação do embrião, formação dos órgãos principais, abertura de boca, pigmentação dos olhos, surgimento das nadadeiras e sistema branquial, dados estes que facilitam a compreensão sobre a ontogenia; além de criar dados embriológicos e anatômicos dessa espécie ainda pouco explorada, conhecimentos estes, imprescindíveis à biologia pesqueira e cultivo das mesmas, sendo também um auxiliar a novas pesquisas. / The knowledge of the early stages of embryonic development in fish is of great importance for the study of native species with potential for aquaculture, since it allows the establishment of guidelines for the breeding of these animals. This project studied the embryonic development of piapara (Leporinus elongatus), a fish of great importance in professional and amateur fishing from the basin of the Pardo and Jequitinhonha rivers, aiming to understand the various stages of development, using bone markers that allowed observation of the bone development in this species. The Bone Morphogenetic Proteins (BMP-2 and BMP-4) are known as key regulatory molecules in embryonic development and bone formation, and information on this subject is scarce in fish. Results shown these proteins could be observed only between the larval to the juvenile stage, not being seen at earlier stages. Scanning electron microscopy and histological techniques, where it was possible to observe the main stages of embryonic development , including , cleavage , embryo differentiation , development of major organs , mouth opening , eye pigmentation , appearance of fins and gills system. This data contributed for the understanding of ontogeny, and provided embryological and anatomical data that may help other studies like reproductive biology of this species that surely will improve reproductive techniques, important goal for raising the piapara.
83

Thermogenic mechanisms during the development of endothermy in juvenile birds

Marjoniemi, K. (Kyösti) 30 October 2001 (has links)
Abstract The use of regulatory and obligatory heat production mechanisms were studied in juvenile birds during the development of endothermy. The development of shivering thermogenesis was studied in the pectoral and gastrocnemius muscles of the altricial domestic pigeon and in three precocial galliforms (Japanese quail, grey partridge and domestic fowl). The development of shivering was the determinant for the beginning of endothermy. Homeothermy also necessitated avoidance of excess heat loss by insulation and behavioural thermoregulation. In the precocial species, shivering thermogenesis was present in the leg muscles of the youngest age groups (1-2 d) studied. Breast muscles contributed shivering from the second post-hatching week. In the altricial pigeons, significant thermogenesis was apparent later than in the precocials, at the age of 6 d. In contrast to the precocials, the pectoral muscles of the altricials were the most significant heat production tissues. In newly-hatched partridges and pigeons, incipient shivering did not result in significant heat production. The ability to produce heat in cold by putative nonshivering thermogenesis was studied in Japanese quail chicks and domestic ducklings. In both species, three-week cold acclimation resulted in morphometric and physiological changes, but there was no clear evidence of nonshivering thermogenesis. The lack of NST was evident because an increase in shivering amplitude at least in one of the muscles studied paralleled an increase in oxygen consumption. Consequently, shivering thermogenesis was probably the only mode of regulatory heat production. The amplitudes of shivering EMGs measured during cold exposure were dependent on the coexistence of postprandial thermogenesis or exercise. Japanese quail chicks were able to substitute shivering thermogenesis partially with postprandial heat production when nourished. Bipedal exercise both inhibited shivering in pectorals directly via inhibitory neural circuits and stimulated it indirectly via decreased body temperature. Because of increased heat loss, exercise was not used as a substitute for shivering. Shivering is a flexible mode of thermogenesis and its magnitude can be adjusted according to the magnitude of obligatory thermogenesis. The adjustment works towards energy saving by avoidance of the summation of different modes of heat production. The prerequisite for successful adjustment of shivering is adequate insulation, whose role in preventing excessive heat loss is pronounced during exercise. It is concluded that the energetics of posthatching thermoregulation includes the potential for optimizations in energy use in order to avoid dissipation of waste energy as heat.
84

The drivers and implications of spatial and temporal variation in the feeding ecology of juvenile Chinook Salmon

Hertz, Eric 22 July 2016 (has links)
Feeding ecology of organisms has a critical influence on ecosystem structure, function, and stability, but how feeding ecology of a single organism varies over multiple spatial and temporal scales in nature is unknown. Here, I characterize the factors driving and the implications of variability in feeding ecology of juvenile Chinook Salmon (Oncorhynchus tshawytscha) over multiple spatial and temporal scales using stable isotopes and stomach contents. Significant variation in juvenile Chinook salmon feeding ecology at the individual-level was found to occur off of the west coast of Vancouver Island (WCVI) (British Columbia, Canada). This variation is correlated with a diet shift from feeding on invertebrates to feeding on fish, as the salmon increase in size. I developed a novel Bayesian stable isotope method to model this shift while taking into account the time-lag associated with isotopic turnover. I found that this model was able to replicate patterns seen in a simplified coastal food web, and that resource-use estimates from this stable isotope model somewhat diverged from a compilation of stomach content data. Next, I compared the feeding ecology of Chinook Salmon in one season and year along nearly their entire North American range. I found considerable spatial variation in ontogeny and feeding ecology, with individuals of the same size from different geographic regions having different δ13C, δ15N, and trophic levels. These differences likely corresponded to regional variability in sea surface temperature, ocean entry date and size, and growth rates. Subsequently, I quantified temporal shifts in the feeding ecology of Chinook Salmon from WCVI. I found that feeding ecology over winter was different from feeding ecology in the fall, and that this likely corresponds to shifts in the prey field. Finally, I found that WCVI juvenile Chinook Salmon showed significant interannual variability in feeding ecology, and that the interannual variability in the δ13C value of juvenile salmon (indicative of primary productivity or nutrient source) predicts their smolt survival. In turn, large-scale climate variability determines the δ13C values of salmon—thus mechanistically linking climate to survival through feeding ecology. These results suggest that qualities propagated upwards from the base of the food chain have a cascading influence that is detectable in salmon feeding ecology. I conclude that the feeding ecology of juvenile Chinook Salmon varies on individual, spatial, season and interannual scales, and that this variability has impacts on survival rates. These findings have implications for the understanding of ontogeny in natural systems in general, allowing for modelling of ontogeny in previously intractable ecological systems. Furthermore there may also be implications for Chinook Salmon management, considering that feeding ecology showed utility as a mechanistic leading indicator of survival rates. / Graduate
85

Competência para a expressão da fotossíntese CAM em plantas de Guzmania monostachia (Bromeliaceae) em diferentes fases ontogenéticas / Competence for CAM photosynthesis expression in different ontogenétic stages of plants of Guzmania monostachia (Bromeliaceae)

Leonardo Hamachi 06 November 2013 (has links)
A Guzmania monostachia é uma espécie de bromélia heteroblástica, ou seja, na fase juvenil, ela apresenta a forma atmosférica e na fase adulta, ela adquire uma estrutura chamada de tanque, que pode armazenar água e nutrientes em momentos de seca esporádica. Ela também é reconhecida por ser C3-CAM facultativa, podendo ser induzida ao CAM através de estímulos ambientais como o a escassez d\'água. Estudos com outras espécies competentes para a expressão do CAM, há relatos de que tecidos jovens expressariam preferencialmente a fotossíntese C3 e passariam a expressar o CAM à medida que se tornassem maduros. No Laboratório de Fisiologia do Desenvolvimento Vegetal a indução do CAM em plantas adultas da espécie G. monostachia por déficit hídrico foi estudada e pôde-se constatar que essa bromélia possui folhas com regiões funcionais distintas: a porção basal seria responsável pela absorção de água e nutrientes e a porção apical encarregada de realizar, principalmente, a fotossíntese. Contudo, ainda não se possuía informação sobre como a ontogenia e as mudanças morfológicas estariam influenciando a competência para a expressão do CAM em folhas inteiras e nas diferentes porções foliares de G. monostachia. A fim de se caracterizar o CAM nesta espécie ao longo da ontogenia, foram selecionadas plantas em 3 fases ontogenéticas (Atmosférica, Tanque-1 e Tanque-2) e das fases Tanque-1 e 2 foram separados grupos de folhas representando 3 estágios de desenvolvimento (F1 - as 7 mais internas da roseta, F2- as 7 folhas seguintes da roseta e F3 - as 7 folhas localizadas mais na base da roseta). As plantas foram submetidas a 7 dias de déficit hídrico por meio da suspensão de rega. Outra coleta de material vegetal foi realizada com plantas Tanque-2 separando-se as folhas em grupos representando os mesmos 3 estágios de desenvolvimento utilizados no experimental anterior e dividindo-as em porções basal e apical. Medidas morfométricas foram feitas para caracterizar cada fase ontogenética. O teor de água dos tecidos das folhas foi determinado e o CAM foi detectado através do ensaio enzimático da PEPC, da MDH e da quantificação dos ácidos orgânicos (ácido cítrico e málico). As plantas Tanque-2 apresentaram mais que o dobro da capacidade de estocagem de água comparativamente às plantas Tanque-1. As plantas atmosféricas sofreram as maiores perdas de água em sua folhas (aproximadamente 50%); já as plantas com tanque tiveram decréscimos mais discretos no teor hídrico (em torno de 15%). Plantas de todas as fases ontogenéticas acumularam significativamente ácido málico durante a noite, evidenciando que, independente da ontogenia, as plantas foram competentes para expressar o CAM. De maneira semelhante, tanto as folhas mais jovens quanto as mais maduras exibiram acúmulos significativos de ácido málico, indicando que elas foram capazes de expressar o CAM nos 3 estágios de desenvolvimento escolhidos para este estudo. Portanto, no conjunto dos experimentais realizados, sugere-se que o fator mais importante para a expressão do CAM em plantas de G. monostachia seja o teor de água dos tecidos foliares e não a ontogenia. Plantas atmosféricas apresentaram a maior perda de água (aproximadamente 50%) concomitantemente à expressão do CAM. Já as regiões apicais dos grupos de folhas F1 das plantas Tanque-2 exibiram um decréscimo de 7% com acúmulo noturno de ácido málico e os grupos F2 e F3 perderam 12% da água de seus tecidos, resultando na inibição do CAM. Há indícios que o transporte de água nas plantas com tanque sob estresse hídrico ocorra das folhas mais maduras para as folhas mais jovens. Aparentemente, plantas jovens atmosféricas de G. monostachia possuem a capacidade de manter seu metabolismo mais ativo mesmo em condições que resultem em uma baixa quantidade de água nos tecidos foliares, indicando um certo grau de tolerância à seca. Ao contrário, nas plantas com tanque, essa capacidade parece não ser tão acentuada, sugerindo que esta fase esteja mais relacionada com estratégias de evitação à seca / Guzmania monostachia is a species of heteroblastic bromeliad, in other words, whereas in the juvenile phase, it assumes the atmospheric form, in the adult, it acquires a structure called a tank, by which water and nutrients can be stored in moments of sporadic drought. It is also recognized through being C3-CAM facultative, thus inducible to CAM through environmental stimuli, such as the lack of water. In the young plants of other species capable of CAM expression, there are reports of preferential C3 photosynthesis expression in young tissues, leading to CAM expression on reaching maturity. In the Laboratory of Plant Development Physiology, studies were made of CAM induction in adult plants of the species G. monostachia during the lack of water at times of drought. It was noted that this bromeliad possessed leaves with distinct functional regions: whereas the basal portion was responsible for the absorption of both water and nutrients, the apical was mainly responsible for photosynthesis. Nonetheless, there was no available information on how ontogeny and morphological changes could influence competence for CAM expression throughout the whole leaf, as well as in the different parts. In order to characterize CAM in this species throughout ontogeny, selection was concentrated on plants in the three ontogenetic phases (Atmospheric, Tank-1 and Tank-2), as well as in the Tank-1 and Tank-2 phases by separating groups of leaves representing the three stages of development in the rosette, viz., Stage1 - the seven inner-most leaves, Stage2 - the next seven, and Stage3 - the seven located more at the base. By suspending irrigation, all the plants were submitted to 7 days without water, whereupon further material was collected from Tank-2 plants. The leaves thus obtained were first divided into groups representing the same three developmental phases as used in the preceding experiment, and then separated into basal and apical portions. Morphometric measurement was applied to the characterization of each ontogenetic phase. Tissue water content in the leaves was defined, and CAM detected through PEPC enzymatic assaying, MDH, and organic acid (citric and malic) quantification. Tank-2 plants presented more than double the capacity to store water, when compared to Tank-1 plants. Whereas atmospheric plants underwent the greatest leaf-water loss (around 50%), the loss was less in those with tanks (around 15%). Significant nocturnal malic acid accumulation in plants in all the ontogenetic phases, placed in evidence plant competency for CAM expression, independent of the stage of development. Likewise, significant malic acid accumulation in both young leaves and more mature ones indicated their capacity for CAM expression in the three stages of development chosen for the present study. Thus, in the experiments carried out, it can be presumed that the most important factor for CAM expression in G. monostachia plants is leaf-tissue water content, and not ontogeny. Atmospheric plants presented the highest water loss (around 50%), which was concomitant with CAM expression. On the other hand, in the apical regions of Tank-2 plants, there was a drop of 7% in water content with nocturnal malic acid accumulation in stage-1 leaves, and a loss of 12% in tissue water in those in stage 2 and 3, with the consequential CAM inhibition. There is every indication that water-transport in tank plants undergoing water-stress occurs from more mature leaves to those younger. Apparently the more active metabolism in young G. monostachia atmospheric plants, even under conditions inducing low leaf-tissue water content, indicates a certain degree of drought tolerance. On the contrary, although this capacity in tank plants appears to be less accentuated, the tank phase is apparently more related to strategies for avoiding the effects of drought
86

Personality of a clonal gecko Lepidodactylus lugubris: developmental mechanism and relation to microhabitat use / クローン種ヤモリにおける個性の発達形成および微環境利用との関連

Sakai, Osamu 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第21603号 / 理博第4510号 / 新制||理||1647(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)准教授 森 哲, 教授 沼田 英治, 教授 中務 真人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
87

Ontogeneze personality aneb opakovatelnost v behaviorálních a kognitivních testech / Ontogeny of personality or repeatability in behavioral and cognitive tests

Pšeničková, Eliška January 2021 (has links)
Individual stability is important for the development of personality, and above all two patterns of consistency - structural and differential. The main goal of this diploma thesis was to monitor changes in the repeatability of behavior over time (i.e., differential consistency) during ontogenesis and to compare the consistency of selected elements of behavior in behavioral tests and a selected cognitive test. Testing of a model species of squamate reptile, the common leopard gecko (Eublepharis macularius), in standard behavioral tests and in a selected cognitive test across ontogenesis over three life stages (juvenile, subadult and adult phase) showed, after statistical examination, high estimates of repeatability and significant influence of ontogenetic phase. Behavioral consistency between juveniles and adults could increase or decrease for certain behaviors or remain consistent in only one phase of life. In the subadult period, the behavior was generally inconsistent, except for vocalization in the reactivity test, where it was demonstrated by high estimates of repeatability. The aim of testing in the selected cognitive test was to determine the non-cognitive component of variability, which could be explained by different personalities. Yet, cognitive styles associated with personality have not...
88

Extrinsic regulation of Hematopoietic Stem Cells in the fetal liver

Lee, Yeojin January 2021 (has links)
Hematopoietic stem cells (HSCs) lie at the top of the hematopoietic hierarchy and give rise to all mature blood cells. They are tightly regulated not only by cell-intrinsic but also cell-extrinsic mechanisms that allow HSCs to respond to dynamic physiological demands of the body. HSCs build the hematopoietic system during development and maintain homeostasis in adults by changing their properties according to different needs. A niche is the microenvironment where HSCs reside and receive extrinsic regulation. Understanding the niche is crucial for elucidating how HSCs are regulated by extrinsic cues. During mammalian development, HSCs pass through several different niches, among which the liver is the major site for their rapid expansion and maturation. The fundamental question of what cells constitute the fetal liver niche in vivo remains largely elusive. It is also unclear whether and how cell-extrinsic maintenance mechanisms accompany changes in HSC properties during ontogeny. Here, I genetically dissected the cellular components of the HSC niche in the fetal liver by identifying the cellular source of a key cytokine, stem cell factor (SCF). In addition, I found that HSCs switch to depend on thrombopoietin (TPO), another key factor, during ontogeny and uncovered the mechanism by which HSCs gain this dependence.
89

Organická paměť v embryonálním vývoji / Organic memory in embryonic development

Švorcová, Jana January 2012 (has links)
The submitted thesis deals with the topic of organic memory, its definition and function, as well as its conceptions from various historical points of view. I use the term "organic memory" in respect to some authors who have previously dealt with this subject (Elsasser 1987, Otis 1994, Barbieri 2003) and also as a term by which to represent a kind of memory distinct from neuronal/cerebral memory. The general memory metaphors (in the case of neuronal memory) are essentially connected with terms such as storage, matrix, or place. For rather materialistic conception of memory, it is also symptomatic that different states such as emotions or mental faculties can be concretely localized in the brain tissue. On the contrary, some philosophers described memory as a primarily temporal entity without connection to place or matter. The question of organic memory was already vivid in 19th century biology, linked to Lamarckian philosophy (Hering 1870, Haeckel 1876, Butler 1910). The organic memory ideas floundered between vitalistic and rather materialistic conceptions: the first attributed some psychological features to cells or memory particles; the second was based on physics or in Cartesian doctrine, and described memory as essentially localized as a kind of storage of traces or patterns of physical waves....
90

Social behaviour of the Eland (Tayrotragus Oryx) on Loskop Dam Nature Reserve

Underwood, Roderick 21 February 2012 (has links)
Please read the abstract on page 3. Copyright 1975, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Underwood, R 1975, Social behaviour of the Eland (Tayrotragus Oryx) on Loskop Dam Nature Reserve, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-02212012-134828 / > E12/4/130/gm / Dissertation (MSc)--University of Pretoria, 1975. / Zoology and Entomology / unrestricted

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