Дисертації: "Fish - general"

1

Knight, Amelia Cassidy Terhune Jeffery S. "General fish health assessment and age evaluation of impinged fish at steam generating power plants." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/FALL/Fisheries_and_Allied_Aquacultures/Thesis/Knight_Amelia_50.pdf.

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2

Guiny, Eliane M. "Hydraulic and biological aspects of fish passes for dams." Thesis, University of Glasgow, 2001. http://theses.gla.ac.uk/1565/.

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The primary purpose of the dissertation is to quantify the efficiency and operation of various types of fish passes for dams. This is achieved through a novel experiment of testing juvenile salmon in a scale model fish-passes with a range of small structures including vertical slots, orifices, weirs and combinations of all three. Direct comparisons of the efficiency of each type of fish pass in terms of upstream migration. Two identical physical models were constructed, one at the Fisheries Research Services Freshwater Laboratory at Almondbank, Perth, Scotland where observations were made of fish behaviour. The other model at the University of Glasgow, Glasgow tested only hydraulic conditions. The physical models were simplified representations of a reach of a river downstream of a dam, weir or any other obstruction to fish migration. A removable cross wall incorporating one of the types of pass tested divided the flume into two pools. A significantly higher proportion of fish moved through submerged orifices or vertical slots than through weirs for a given flow rate and velocity. The orifice and vertical slot passing efficiencies are directly correlated to the velocities existing in their vicinity. To reach the weir/slot/orifice devices, salmon parr tended also to stay near the bottom of the flume and followed a path along the sides of the arena, which provided them with low velocities and cover. In the vicinity of the weir/orifice/slot devices, the movements of salmon parr were consistent with energy-conserving strategies. Clearly, the extrapolations of results from the behaviour of small to large salmon remains cautious, the intention of this research being to characterise the behaviour of small salmon and to develop clear testable hypotheses about how large salmon may respond to water flow. Preliminary field tests were then conducted at Tongland Dam fish pass to test the main recommendation extrapolated from the parr behavioural study. The particular situation of this fish pass, which contains both weirs and orifices, allows a comparison between the two. Passive Integrated Transponder (PIT) tags together with antennae installed at a weir and an orifice were used to individually monitor the movement of wild spawning salmon passing through the fish pass. The results of the field test are as yet, inconclusive.

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3

Verghese, Bindhu. "Electrophoretic patterns of the general proteins of four species belonging to the Family Carangidae." Thesis, Central Marine Fisheries Research Institute, 1998. http://eprints.cmfri.org.in/11038/1/Bindhu%20Varghese.pdf.

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Muscle proteins usually provide useful information and therefore are frequently used as valuable diagnostic characters in the classification of fishes at species, generic, familial and higher taxonomic levels. The muscle myogen of four species of carangids. viz, Decapterus russelli, D. macrosoma, Selar crumenophthalmus and Megalaspis cordyla using horizontal slab polyacrylamide gel electrophoresis (Gel conc. 7.5%) is reported in the present communication. The number of protein fractions and the presumptive loci in muscle of D. russelli, D. macrosoma, S. crumenophthalmus and M. cordyla were found to be 9,7,6 and 5 respectively. The Rf value ranged from 21 to 84 for S. crumenophthalmus, 2 to 72 for M cordyla, 15 to 89 for D. macrosoma and 18 to 96 for D. russelli. The difference in number of fractions, their mobility pattern and staining intensity indicated species-specificity. With the limited number of samples used in the present work, there has been an indication of intraspecific polymorphism among three species of carangids, being 3.5% in D. russelli, 13.5% in D. macrosoma and 6.6% in S. crumenophthalmus. In M. cordyla no polymorphism was observed. This work also revealed that protein fractions in carangids can be used as species - specific markers, which could be helpful in resolving disputes in the event of any taxonomic ambiguity.

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4

Smith, Eric S. "Refinement of the neutron-alpha and proton-alpha fish-bone potential." Thesis, California State University, Long Beach, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1523064.

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The non-local fish-bone potential simulates the Pauli-exclusion principle for composite particle interactions. This model is used to calculate the phase shifts of the neutron-alpha and proton-alpha systems. We propose a local double Gaussian potential with a new parameterization by fitting to experimental results. These parameters are universal to both nucleon-alpha systems and include all partial waves, which is an improvement over previous work in the field.

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5

Babineau, David. "Modeling the electric field and natural environment of weakly electric fish." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27222.

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Weakly electric fish use a unique sensory modality in order to help them communicate, navigate and find prey. These fish emit electric discharges that are monitored by electroreceptors located in the fish's skin. Surrounding objects perturb these baseline transdermal potentials and create electric images. The study of these images has led to a better understanding of general sensory processing principles; however, many aspects of these fish's natural electrosensory environment remain unknown. To this end, a two-dimensional finite element model of Apteronotus leptorhynchus was created. Using this model, we suggest new ways by which electric fish are able to locate objects and propose that it is possible for these fish to extract useful information from their environment using their natural scanning behaviour. Our results also reveal important limitations in standard experimental paradigms that aim to mimic the effects of conspecifics. Alternative paradigms that will enable more realistic stimulation are suggested.

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6

Larson, Erik. "Serotonin modulates electrosensory processing via 5-HT2 receptors in the weakly electric fish «Apteronotus leptorhynchus»." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123302.

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Accurate sensory processing of the environment is a critical function for any organism to survive. In order to accomplish this function neurons must be specifically tuned to respond optimally to relevant stimuli in their environment. One effective way of efficiently encoding information is for neurons to adapt their responses to stimuli arising from different behavioral contexts. Neuromodulators such as serotonin (5-HT) are thought to help mediate such adaptations. The 5-HT system has been well conserved through evolution across vertebrates, suggesting that its function also been conserved. In the weakly electric fish Apteronotus leptorhynchus, 5-HT has been previously shown to increase sensory pyramidal neurons responses located within the electrosensory lateral line lobe (ELL) to stimuli caused by same-sex conspecifics by making them more excitable in vivo. Remarkably, application of 5-HT in vitro has been shown to also render these neurons more excitable through downregulation of both small-conductance calcium-activated (SK) and M-type potassium channels. However, the nature of the 5-HT receptors present in pyramidal neurons is unknown. By using occlusion experiments while recording from pyramidal neurons in vitro, we show that the selective 5-HT2 antagonist, ketanserin, was able to occlude the effects of 5-HT on pyramidal cells as quantified by changes in firing rate, burst fraction, afterhyperpolarization, and mutual information. Our results show that downregulation of both M and SK currents is most likely achieved through the same receptor family and pave the way for future molecular studies performing in situ hybridization or immunohistochemistry to confirm that 5-HT2 receptors are indeed present in the ELL and solely mediate the effects of 5-HT observed both in vitro and in vivo.
Traitement sensoriel précis de l'environnement est une fonction essentielle pour tout organisme de survivre. Afin d'accomplir ces neurones doivent être spécialement réglés pour répondre au mieux aux stimuli pertinents dans leur environnement. Un moyen efficace de coder efficacement l'information est pour les neurones à adapter leurs réponses à des stimuli provenant de différents contextes de comportement. Neuromodulateurs comme la sérotonine (5-HT) sont pensés pour aider à la médiation de ces adaptations. Le système 5 -HT a été bien conservé à travers l'évolution des vertébrés, ce qui suggère que sa fonction a également été conservée. En Apteronotus leptorhynchus, un des poissons électriques du genre gymnotiformes, 5-HT a déjà été démontré pour augmenter sensorielles pyramidales neurones réponses situées dans le lobe de la ligne-latérale électrosensoriel (LLE) aux stimuli provoqués par des congénères de même sexe en les rendant plus excitable in vivo. Remarquablement, l'application de la 5-HT in vitro a été démontré également de rendre ces neurones plus excitables à travers à la fois la régulation négative de courants potassiques sensibles au calcium (SK) et les courants potassique de type M. Cependant, la nature des récepteurs 5-HT présents dans les neurones pyramidaux est inconnue. En utilisant les expérimentés d'occlusion lors de l'enregistrement de neurones pyramidaux in vitro, nous montrons que l'antagoniste sélectif 5-HT2, ketanserin, a peut bloquer les effets de la 5-HT sur les cellules pyramidales quantifiées par des changements dans le taux de le potentiel d'action, fraction de le potentiel d'action dans une «bouffée», après-hyperpolarisation, et l'information mutuelle. Nos résultats montrent que la régulation négative des courants à la fois M et SK est probablement atteint par la même famille récepteur et ouvrir la voie à des études moléculaires futures comme l'hybridisation in situ ou l'immunohistochimie pour confirmer que les récepteurs 5-HT2 sont bien présents dans le LLE et permettent les effets de la 5-HT a observé à la fois in vitro et in vivo.

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7

Cazan, Alfy Morales. "Maternal transfer of metals in live-bearing fish (Cyprinodontiformes| Poeciliinae)." Thesis, University of Louisiana at Lafayette, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3622929.

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This study assessed the occurrence and impacts of maternal metal transfer in live-bearing fish. The occurrence was investigated in two different species (Gambusia affinisand Heterandria formosa), while the impacts were studied only in G. affinis. Occurrence and impacts were addressed by exposing gravid females for 10 days to 0.15 μM of copper or cadmium, transferring the fish to clean water, monitoring their reproduction and collecting newborn offspring for further analyses of their health and reproductive success.

Maternal transfer of copper and cadmium occured in both study species. Metal levels decreased in subsequent broods and in broods born later after a female's exposure. Metal exposure impacted the reproductive success of exposed-females; effects included smaller broods and more broods were aborted broods or contained dead offspring. Many effects remained for second broods developing well after the exposure.

The maternal metal exposure also impacted the offspring's health. Newborn offspring were smaller at birth, had reduced calcium levels, had a lowered metal tolerance, and had cellular membrane damage. When these offspring grew up, they had an increased rate of malformations, a smaller size at sexual maturity, increased gestation time and fewer broods. In spite of the impacts on life history parameters found in the laboratory, effects on population dynamics were very limited for greenhouse mesocosm populations established with the offspring of exposed females.

Effects for the essential metal (copper) and the nonessential metal (cadmium) were generally similar. A few effects, like those on body size, were evident for copper but not for cadmium. However, several of the more severe impacts, like the increase in malformations and reductions in the number of broods, were greatest for the offspring of the cadmium-exposed females.

This is the first report demonstrating negative impacts resulting from a short-term maternal metal exposure in live-bearing fishes. Effects were evident not just for reproduction of exposed-females but also for their offspring's health and reproduction. The latter continued beyond the offspring that were developing during exposure. This study demonstrated that the internal development in live-bearing fish may not spare the developing young from impacts caused by a metal-contaminated environment.

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8

Padhi, Abinash. "Electrophoretic Profile of the general proteins in the Green (Perna viridis Linnaeus) and the Brown (Perna indica Kuriakose & Nair) mussels." Thesis, Central Marine Fisheries Research Institute, 1998. http://eprints.cmfri.org.in/11022/1/Abinash%20Padhi.pdf.

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The electrophoretic profiles of the general proteins and the selected enzymes (MDH and EST) were examined in the green mussel, P. viridis and the brown mussel P. indica and their suspected hybrids from South India. The protein and the enzyme profiles were distinctly different in the two species. The protein profiles in different tissues of the green and brown mussels were found tissue and species specific. The two species are genetically different. The protein and the enzyme profiles in the brown and suspected ‘brown type’ hybrids were similar and that of the green and the suspected ‘green type’ hybrids were also similar. The suspected hybrids may be the colour morphs of the respective species. Morphometric studies on these two species and the suspected hybrids also corroborated the above findings.

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9

Cuddy, Martin. "Modulations in electrocommunication behaviour and non-invasively measured 11-ketotestosterone during cue-induced seasonal breeding in the weakly electric fish, «Apteronotus leptorhynchus»." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96923.

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Androgens are correlated with reproductive behaviours including courtship and aggression. In the weakly electric fish, Apteronotus leptorhynchus, 11-ketotestosterone (11-KT) has been previously implicated in the regulation of electrocommunication behaviours that are believed to have roles in both aggression and courtship. In this thesis a method for performing repeated, non-invasive measurements of androgens released into the water was validated and applied for the first time in A. leptorhynchus. Changes in 11-KT levels and electrocommunication behaviour were observed in males following environmental cues that simulated the onset of the breeding season. Males showed an increase in mean electric organ discharge frequency (EODf), which is consistent with earlier results showing a female preference for high EODf. A subset of males with high EODfs showed increases in both 11-KT and EODf which provides support for an EODf-based dominance hierarchy in this species. No direct correlation was seen between 11-KT and EODf, however, which suggests that other factors are involved in regulating male EODf. Electrocommunication signals produced during inter-male aggression were confirmed to serve in deterring attacks, and their pattern of production further suggested the formation of a dominance hierarchy. Evidence is presented that another type of electrocommunication signal previously implicated in courtship may be an inter-male signal of submission. The method for non-invasive hormone sampling first applied here will form the basis for future investigations of the hormonal control of communication behaviour.
Les androgènes sont corrélés avec les comportements reproductifs et agressifs. Chez les poissons faiblement électriques Apteronotus leptorhynchus, la 11-ketotestosterone (11-KT) a déjà été impliquée dans la régulation des comportements de communication électriques avec des rôles prévu dans l'agression et la cour. Dans cette mémoire une méthode pour faire des mesures répétées qui ne sont pas envahissantes des androgènes libérés dans l'eau a été validée et appliquée pour la première fois dans A. leptorhynchus. Des changements dans les niveaux de 11-KT et la production des comportements de communication électrique ont été observés chez les mâles pendant une période de reproduction conditionnée. Entre les mâles, il y avait une augmentation de la fréquence de la décharge de l'organe électrique (EODf), ce qui est avec des résultats précédents montrant que les femelles matures ont une préférence pour les mâles avec des EODf élévées. Un sous-ensemble de mâles ayant des EODfs élevée a montré des augmentations dans le niveau de 11-KT et la EODf, ce qui soutient une hiérarchie de dominance fondée sur la EODf. Globalement, aucune corrélation n'a été observée entre 11-KT et EODf, ce qui suggère que d'autres facteurs sont impliqués dans la régulation du EODf dans les mâles. Les comportements de communication électrique produits pendant l'agression entre mâles servent à dissuader les attaques et leur mode de production aussi suggère la formation d'une hiérarchie de dominance. Une preuve est aussi présentée qu'un autre comportement de communication électrique impliqué dans la reproduction peut être un signal masculin de la soumission. À l'avenir, la méthode appliquée ici pour la première fois chez les poissons faiblement électriques sera en mesure de répondre à ces questions en profondeur.

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10

Bacher, Kathrin. "Interactions between fish farming, wild fish populations, local fisheries and society: a case study in Catalonia, Spain." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/284844.

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The overarching goal of this doctoral thesis was to advance the understanding of the interactions between marine fish farming, wild fish populations, the local small-scale fishery and the society. This thesis was designed as a multi-disciplinary study and is divided into three different sections: ecology (chapter 1 and 2), fisheries (chapter 3) and social science (chapter 4). In the ecological part we examined the spatial and temporal extent of the attraction effect of wild fish at an Atlantic bluefin tuna and a Gilthead seabream farm. At both farms wild fish aggregated closely to the cage structure, revealing an abrupt decline of fish abundance rather than a gradient. The intensity of the cage effect varied according to farm, season and depth. At the seabream farm, the cage effect persisted year round, whereas at the tuna farm, the effect was restricted to summer and spring. The variability of wild fish aggregations within the Gilthead seabream farm was analyzed because it can be a distorting factor in estimating the farm attraction effect. Our findings showed that at the surface, fish abundance was significantly higher during feeding compared with non-feeding periods. Moreover, the distance from the feeding vessel significantly influenced fish aggregations in the water column. At the bottom, substrate type was the dominant factor explaining aggregation variability. The effect of fish farming on the small-scale fishery was evaluated in order to determine whether farms act as protection zones or as traps for wild fish populations. The findings revealed a relevant amount of commercial and recreational fishing effort in farm vicinity. However, the results showed no benefit or difference of fishing in close proximity to the farm compared to areas away from the farm (in terms of yield, income, and catch composition). Yet, farm-aggregated fish are vulnerable to hidden fishing practices inside the farm. The analysis of the perception of marine fish farming in Catalonia was performed with five key stakeholder-groups (NGOs, local fishermen, fish farming industry, scientists and regional administration). Four perceptions were identified; two represented divergent views and two intermediate positions. Environmental impacts were not perceived as a high risk by the majority of the participants. The major weaknesses were attributed to economic (e.g. price competition with other producer countries) and social issues (e.g. lack of credible information about farmed products). Overall, this thesis provides new information about the complex dynamics of wild fish aggregations at marine fish farms and investigates how this attraction effect influences the local small-scale fishery. Moreover, an understanding of the different perceptions on marine fish farming can help to secure a social, economic and environmental sustainable activity.
Esta tesis persigue avanzar en el conocimiento de las interacciones de la piscicultura marina, de carácter multidisciplinar y estructurada en tres áreas: ecología (capítulos 1 y 2), pesca (capítulo 3) y ciencias sociales (capítulo 4). En el área de ecología, se analizó la extensión espacial y temporal del efecto atractor de peces salvajes sobre dos tipos de granjas: atún rojo (Thunnus thynnus) y dorada (Sparus aurata). En ambas el efecto atractor se restringía al límite de las jaulas, variando estacionalmente y en profundidad. Las diferencias entre granjas, permanente en doradas y estacional en atunes, se deben a diferencias en la composición específica asociadas con la localización y tipo de cultivo. El análisis de la variabilidad interna en la comunidad íctica se analizó ya que podría ser un factor distorsionador en la estimación del efecto atractor. Los resultados mostraron que la abundancia de peces en superficie disminuía significativamente en los períodos de no alimentación y durante la alimentación las concentraciones de peces disminuían en función de la distancia al barco alimentador. Por el contrario, la variabilidad de agregación en el fondo dependía exclusivamente del tipo de sustrato. La interacción con la pesca artesanal se evaluó con el fin de conocer si las granjas actúan como zonas de protección o como trampas para los peces salvajes. Los resultados no mostraron beneficio, detrimento o diferencia de la pesca en las proximidades de la granja respecto a zonas distantes (en términos de producción, ingresos y composición de las capturas). El análisis de la percepción de la acuicultura, indicador del escenario de aceptación y de elementos clave para su desarrollo, se realizó sobre cinco grupos de interés (ONGs, pescadores locales, industria de la piscicultura, científicos y administración regional) en el marco regional de Cataluña. Se identificaron cuatro percepciones; dos claramente divergentes y dos de posturas intermedias. Los impactos ambientales no fueron percibidos como de alto riesgo por la mayoría de los actores. Las principales debilidades fueron atribuidas a aspectos económicos (p. ej. la competencia con otros países productores) y sociales (p. ej. la falta de información acerca de la credibilidad de los productos acuícolas).

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11

Chitheer, T. "Eco-evolutionary feedback in fish-zooplankton communities on the Scottish island of North Uist." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/51741/.

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‘Eco-evolutionary feedbacks’ occur when evolution of organismal traits causes environmental change that drives further evolution. Predator and prey interactions provide good examples of eco-evolutionary feedbacks. Here I examine the potential for eco-evolutionary feedbacks between three-spined sticklebacks (Gasterosteus aculeatus, hereafter ‘stickleback’) and their zooplankton prey in lochs (lakes) on the Scottish island of North Uist. Many lochs on the island were colonised by sticklebacks after the last glaciation, approximately 10,000-15,000 years ago. Previous work has shown that sticklebacks in different lochs have diverged greatly from each other in response to local environments. On the other hand, apart from several very old studies on the occurrence of some zooplankton species, there have been no previous in depth studies on the population dynamics of zooplankton on North Uist. I investigated first the diversity and abundance of zooplankton groups and the most common species across all North Uist lochs. Thirty-nine species were classified from three main groups (Rotifera, Cladocera and Copepoda). Species abundance in the presence of fish was relatively more even, while the abundance of zooplankton groups was not generally related to fish presence except for Cladocera in a subset of locations. The effects of predation on the life-history of zooplankton were also examined by comparing reproductive traits of the dominant cladoceran species (Bosmina and Daphnia) in lochs with and without fish. Cladocerans in lochs with fish have more rapid reproductive cycles and higher fecundity parameters, probably in response to the increased threat of predation. These effects remain evident in Bosmina after they have been raised through three generations in the laboratory, supporting the hypothesis that they have a genetic basis and are not a plastic response to predator presence. Life-history variables of cladocerans were also related to abiotic and biotic variation among lochs, including depth, pH, chlorophyll levels and the concentration of alkaline metals. I also demonstrate that stickleback have diversified greatly among lochs in functional trophic traits that determine the efficiency of feeding on different types of prey, which could affect total primary production and the structure of prey communities. Ancestral stickleback populations have adapted according to the type of habitat colonised. Fish feed on benthic prey in shallow lochs, which requires greater effort for successful foraging than that required by fish that feed on planktonic prey. I found that variation in stickleback trophic traits was related to both abiotic and biotic variation among lochs, including loch depth and the mean contributions of planktonic and benthic prey to diet. The results presented in this thesis suggest the possibility of eco-evolutionary feedbacks in these simple ecosystems on North Uist based on the significant responses in fish and zooplankton communities. The thesis also provides a basis for further studies on fish-zooplankton interactions on North Uist and contributes to the wider body of knowledge concerning the relevance of natural variation in shaping the foraging mechanisms of animals.

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12

Codina, Pascual Montserrat. "Estudi de la sinapsi i de la recombinació meiòtica en espermatòcits humans mitjançant immunocitofluorescència i stM-FISH." Doctoral thesis, Universitat Autònoma de Barcelona, 2006. http://hdl.handle.net/10803/3766.

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Durant la profase I meiòtica els cromosomes homòlegs s'uneixen mitjançant sinapsi formant els bivalents i intercanvien material genètic per recombinació homòloga. Al llarg de l'eix de sinapsi s'estructura el complex sinaptinemal (CS). Anomalies de la sinapsi i de la recombinació meiòtica s'han considerat com dos possibles causes de bloqueig total o parcial de la meiosi. L'objectiu general d'aquet treball és estudiar la incidència d'anomalies sinàptiques i de recombinació en individus controls i infèrtils per a caracteritzar diferents graus d'anomalies en aquests processos en la infertilitat idiopàtica.
S'han processat biòpsies testiculars de set individus control i de tretze infèrtils. La detecció immunofluorescent de proteïnes de CS (SCP1 i SCP3) i de llocs de recombinació (MLH1) s'ha utilitzat por primera vegada en combinació amb un mètode de hibridació in situ fluorescent amb múltiples sondes subtelomèriques específiques (stM-FISH), que permet la identificació de tots els SCs d'una cèl·lula a paquitè.
Les regions d'heterocromatina no centromèrica, 9qh, 1qh, 16qh i braços curts dels cromosomes acrocèntrics, han presentat una major incidència d'anomalies sinàptiques, indicant que són les últimes regions del genoma en fer sinapsi. La incidència d'anomalies sinàptiques en aquestes zones varia entre individus, fet explicable per polimorfismes d'aquestes regions en la població general. Anomalies sinàptiques en altres zones, aquelles que afecten a varis CSs en un mateix nucli o aquelles presents en estadi de paquitè tardà podrien indicar una afectació severa de la sinapsis. Els CSs dels cromosomes 15 i 21 s'associen més freqüentment al parell de cromosomes sexuals possiblement degut a l'homologia existent entre les regions heterocromàtiques d'aquests cromosomes i la del cromosoma Y.
L'anàlisi de la recombinació meiòtica ha mostrat que la recombinació homòloga en el parell XY pot ser un indicador de la freqüència general de recombinació i de la progressió de la meiosi. Els resultats confirmen que una menor freqüència de recombinació pot augmentar el risc d'univalents a metafase I i que les diferències entre individus en aquesta freqüència podrien explicar la variabilitat en la freqüència d'aneuploïdies en espermatozoides humans. Els resultats de distribució de punts de MLH1 en cada CS i de les distancies entre aquests punts ens ha permès proposar un model de com es distribueixen aquests punts al llarg del CS.
L'anàlisi de la longitud del CS ha mostrat que cada un dels braços del CS, de manera independent a l'altre, pot variar la seva longitud relativa en comparació a la longitud relativa dels cromosomes mitòtics. En el treball s'evidencia que aquesta variació de la longitud relativa pot reflectir la quantitat de fibres compactes i no compactes de cromatina presents a la zona.
Finalment, la observació d'una cèl·lula tetraploide en estadi de paquitè, possiblement originada per endoreduplicació, demostra que la sinapsi i la recombinació meiòtica poden tenir lloc en aquestes cèl·lules en humans. A més a més, permet suposar que aquestes cèl·lules són un altre possible origen de espermatozoides diploides.
Durant el transcurs d'aquest estudi s'ha caracteritzat citogenèticament un isocromosoma dicèntric Yq(p11.32) en mosaic en un individuo azoospermic, mitjançant FISH amb sondes específiques pel cromosoma Y.
During meiotic prophase I, homologous chromosomes are joined forming bivalents and they exchange genetic material by the processes of synapsis and crossing over. The synaptonemal complex (SC) appears along the synapsis axis. Synapsis and crossover anomalies have been considered as two possible causes of partial or total meiotic arrest. The general aim of this study is to analyse the incidence of synaptic and crossover anomalies in controls and infertile men in order to characterise different degrees of anomaly in these processes in idiopathic infertility.
Testicular biopsies from seven controls and thirteen infertile men have been processed. Immunolabelling of SC proteins (SCP1and SCP3) and of DNA mismatch repair proteins present in crossover foci (MLH1) has been applied, for the first time, in combination with the seven-fluorochrome subtelomere-specific multiplex FISH assay (stM-FISH) in order to analyse synapsis and crossovers individually in each SC of a nucleus at pachytene.
SCs regions with non-centromeric heterochromatin, 9qh, 1qh, 16qh and short arms of acrocentric chromosomes, have presented the highest incidence of gaps and splits, indicating that these are the last regions in the genome to synapse. Interindividual variability in the incidence of synaptic anomalies in these regions may be explained by polymorphisms of these regions in the general population. Synaptic anomalies in other SC regions, those affecting several SCs or present in late pachytene nuclei may indicate nuclei with a severely affected synapsis. Autosomal SC15 and SC21 associate with the XY pair more frequently than other SCs, possibly due to the homology between non-centromeric heterochromatins in the short arm of chromosomes 15 and 21 and in the q arm of chromosome Y.
The analysis of crossovers shows that the amount of XY pairs with a crossover could be an indicator for general crossover frequency and for a successful meiotic process. Results confirm that reduction in the crossover frequency may increase the risk of achiasmatic small bivalents, and that interindividual differences in crossover frequency could explain the variability in the frequencies of aneuploidy in human sperm. How MLH1 foci are positioned within the SC is discussed based on detailed MLH1 foci distributions and interfoci distances.
SC length analysis has shown that SC arms can be longer or shorter than the corresponding mitotic ones. Moreover, for a given SC, the variation in length found in one arm was independent of the variation observed in the other one. Evidence that the variation of the SC arm length may reflect the abundance of open and of compact chromatin fibres in the arm is shown.
The finding of a tetraploid pachytene, possibly originated by endoreduplication, demonstrates that synapsis and crossover events can occur in these cells in humans. Moreover, it indicates that diploid sperm may also originate from tetraploid meiotic cells.
During this study, a dicentric Yq(p11.32) isochromosome has been cytogenetically characterised in an azoospermic male by FISH using specific probes for chromosome Y.

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13

Yazgan, Tavsanoglu Ulku Nihan. "Zooplankton Adaptation Strategies Against Fish Predation In Turkish Shallow Lakes." Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615354/index.pdf.

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In this study, the factors influencing zooplankton community structure in Turkish shallow lakes were elucidated with four main approaches: (i) space-for-time substitution for shallow lakes using snap-shot sampling in 31 lakes along a latitudinal gradient
(ii) in-situ mesocosm experiments in eleven lakes along a latitudinal gradient using three sets of artificial plants systems
(iii)&lsquo
Habitat Choice&rsquo
laboratory experiments mimicking a &lsquo
shallow littoral&rsquo
zone with plants and a &lsquo
deeper pelagic&rsquo
zone with sediments testing the response of Daphnia magna to predation cues
and (iv) long-term monitoring data (1997-2011) from two interconnected lakes. Snap-shot and long-term monitoring showed that eutrophication has a strong influence on the zooplankton community via increased fish predation, nutrient loading and salinization. Here too the zooplankton community shifted towards a smaller sized profile, especially in lakes located at lower latitudes. Moreover, The laboratory and in-situ mesocosm experiments revealed that under predation risk Daphnia preferred to hide near sediment instead of using submerged plants as a refuge. Accordingly, in-situ mesocosm experiments revealed a predation pressure induced size structure shift towards small-medium sized zooplankton and calanoid copepods. The long-term monitored lakes experienced (i) drought-induced water level drop, leading to increased salinity and eutrophication, and consequent anoxic conditions and fish kill
as well as (ii) biomanipulation in the downstream. Both conditions resulted in major reduction in the top-down control of fish and ultimate predomination by large sized Daphnia spp. Nevertheless, the excessive exploitation of lakes and ongoing warming entail Turkish shallow lakes to become more eutrophic, making this study indicative for the Mediterranean region.

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14

Konovalenko, Lena. "Element transport in aquatic ecosystems – Modelling general and element-specific mechanisms." Doctoral thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-110064.

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Radionuclides are widely used in energy production and medical, military and industrial applications. Thus, understanding the behaviour of radionuclides which have been or may be released into ecosystems is important for human and environmental risk assessment. Modelling of radionuclides or their stable element analogues is the only tool that can predict the consequences of accidental release. In this thesis, two dynamic stochastic compartment models for radionuclide/element transfer in a marine coastal ecosystem and a freshwater lake were developed and implemented (Paper I and III), in order to model a hypothetical future release of multiple radionuclides from a nuclear waste disposal site. Element-specific mechanisms such as element uptake via diet and adsorption of elements to organic surfaces were connected to ecosystem carbon models. Element transport in two specific coastal and lake ecosystems were simulated for 26 and 13 elements, respectively (Papers I and III). Using the models, the concentration ratios (CR: the ratio of the element or radionuclide concentration in an organism to the concentration in water) were estimated for different groups of aquatic organisms. The coastal model was also compared with a 3D hydrodynamic spatial model (Paper II) for Cs, Ni and Th, and estimated confidence limits for their modelled CRs. In the absence of site-specific CR data, being able to estimate a range of CR values with such models is an alternative to relying on literature CR values that are not always relevant to the site of interest. Water chemistry was also found to influence uptake of contaminants by aquatic organisms. Empirical inverse relationships were derived between CRs of fish for stable Sr (CRSr) and Cs (CRCs) and water concentrations of their biochemical analogues Ca and K, respectively (Paper IV), illustrating how such relationships could be used in the prediction of more site-specific CRCs and CRSr in fish simply from water chemistry measurements.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

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15

Kepenek, Ayse Ozge. "Preliminary Approch For The Determination Of Fish Exuded Kairomone Using Fourier Transform Infrared Spectroscopy." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12606942/index.pdf.

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Chemical communication in aquatic organisms has been topic of a large number of studies focusing interactions between organisms via info chemicals. Diel Vertical Migration (DVM) is commonly observed among zooplankton and consists of a single daily ascent with minimum depth reached between sunset and sunrise and a descent with maximum depth attained during the day. DVM was absent or reduced when predators were absent and well developed in their presence. Species of the Daphnia are one of the well investigated group in freshwater environments. Variation in DVM of Daphnia in response to fish kairomone is one of the best studied behavioral strategies. Kairomone, as a term, is described interspecific chemical messengers, the adaptive benefit of which falls on the recipient rather than the emitter. As a result, nature and origin of kairomone is still unclear and needs to be investigated. It was decided that FT-IR technique would be favorable tool for this aim. In this frame, it was conceived that the occurrence of migration adaptation relevant to the seasonal changes in the presence of fish kairomone could be proved and characterized by FT-IR technique. Results of the present study indicate that non-aromatic, secondary amine compound has significant contribution to fish cue. Since other sources other than fish can contribute the natural amine compounds level in fresh water environment, origin and concentration of amines are needed further investigation to determine ecological function of amine.

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16

Lorenzi, Varenka. "The Behavioral Neuroendocrinology of Fish Sex Change: The Role of Steroids and Monoamines." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/biology_diss/76.

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Social status influences reproductive physiology in many species, and sex change in marine teleost fishes provides an excellent model to understand how an organism can modulate its reproductive system in response to social stimuli. The series of experiments presented in this dissertation has focused on the proximate mechanisms underlying sex change and, in particular, the neuroendocrine factors that might translate social information into physiological changes. The bluebanded goby (Lythrypnus dalli) is a sexually plastic fish, and the dominant female typically changes sex when the male is removed from the social group. The direct physical interactions between the male and the females were found to be the main sensory cues that inhibit sex change. Sex steroids can both modulate and be modulated by behavior, and as a result they have been the most obvious candidates for a key role in the regulation of sex change. Males and females showed similar diurnal patterns for steroid hormones, but females had significantly higher water-borne estrogen levels. Concentrations of estradiol, testosterone and 11-ketotestosterone presented sex and tissue differences in brain, gonad and muscle, and they varied in complex ways in different tissues during sex change. The neurotransmitter serotonin (5-HT) has been suggested to be involved in the inhibition of socially regulated sex change because of its role in the modulation of both reproductive and aggressive behavior. None of the pharmacological manipulations performed in L. dalli to alter serotonergic activity was able to overcome the input from the social environment and affect sex change. Neither monoamine levels nor the area or number of 5-HT immunoreactive neurons were different between males, females and sex changers or between dominant and subordinate females. The results do not support the hypothesis of a serotonergic inhibition on sex change in L. dalli, but show that rapid changes in brain androgen levels might be implicated in inducing behavioral or morphological changes associated with sex reversal. Also, steroids respond to changes in the social environment in different ways in different tissues so local steroid synthesis should receive greater attention, and caution is required when using circulating levels to understand behavioral regulation.

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17

Ok, Meltem. "Evaluation Of The Demersal Fish Assemblages Of The Northeastern Levant Sea." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615068/index.pdf.

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Ecosystem-level changes have taken place in the Mediterranean Sea over the last decades due to both anthropogenic interferences and natural perturbations. Compared to the western Mediterranean Sea, influences of these factors especially on flora and fauna characteristics are much more dramatic and intense in the eastern part, particularly in the northeastern Levant Sea where the study area is located. In this study, life history traits of some core species (both native and immigrant) occupying the continental shelf of the northeastern Levant Sea were studied in this changing ecosystem to improve limited ecological understanding of the demersal fish assemblages of the northeastern Levant Sea. For this purpose, the annual patterns in allocation and utilization of energy in demersal fish species, temporal and bathymetrical trends in fish distribution with respect to biological requirements of the species and strategies adapted by the species in growth, reproduction and energy storage were investigated by examining growth parameters, biological indices and abundance and biomass variations. Influences of environmental variables on spatiotemporal distribution and biological characteristic of Mullus barbatus were also explored by generalized additive models. Biological data were collected at monthly intervals between May 2007 and May 2010 by trawl sampling while sample collection of environmental variables (temperature and salinity) was performed from December 2008 to May 2010. Results of this study reveal that the components of the demersal fish assemblage in the region fulfill their biological activities within a short period of time when the highest productivity is reached in the area. Moreover, results indicate that within this short period of time, some native components of the demersal fish assemblages studied (Mullus barbatus and Pagellus erythrinus) exhibit strategies such as fast growth, early maturation, short reproduction season, secondary spawners to cope with the environmental peculiarities. On the other hand, the successful exotic colonizers develop strategies as well but these successful immigrants also use time (Lagocephalus suezensis) and space (depth) (Upeneus pori) slot that the native species avoid. In some of the species examined (Mullus barbatus and Lagocephalus suezensis), growth is fast, sexual maturity is early, reproduction period is short, and reproduction potential is high. With the peculiar environmental condition, these life history traits are attributed to the &ldquo
r-strategy&rdquo
of the species. In this study, generalized additive models of Mullus barbatus explain 81.5 % variations in Gonadosomatic Index (GSI), 55.2 % in Hepatosomatic Index (HSI) and 43.9 % in Condition Factor (K). The time component in the GAM model captures the same cyclic pattern observed in GSI of Mullus barbatus. Besides, The GAM results suggest that the highest GSI values associated with the bottom water temperature are between 18 &ndash
19 °
C while the partial effect of bottom salinity is at 38.7 psu. A positive effect of depth on GSI of the species starts after 60 meters depth and increasing trend continues until 125 meters depth and then decreases. The HSI results are almost identical to GSI outputs indicating that the effects of the parameters concerned act in a similar manner. The results of the GAM models failed to explain influence of environmental parameters on vertical and seasonal distribution of adult Mullus barbatus. However 83.5 % variances were explained in distribution of juveniles. The salinity and temperature have the highest impact on the distribution of juveniles among the parameters evaluated. The results indicate that the occurrence of Atlantic Water in the area has a positive influence on M. barbatus, particularly on the recruits through either by its low salinity or by another factor associated with this water mass. The vertical distribution range are set by the high temperatures (>
27 °
C) at the shallow depths during summer and the low temperatures on the shelf break zone (<
16 °
C). A comparison of vertical abundance distribution of Mullus barbatus and the vertical temperature variations indicate that the species may tolerate up to 27 °
C and then individuals move to the deeper depths so that to the cooler waters when the temperature exceeds their tolerance limit. As well as the life history traits adopted by the species, there are some other factors providing advantages to the species. The fisheries regulations, particularly the time limits applied in the area are in favor of the species especially of pre-recruits. In the study area the pre-recruitment phase and summer YOY aggregations in shallow waters of most species studied in this thesis take place during a time when the fishing season is closed.

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18

Murray, David S. "The role of physical structure and micronutrient provisioning in determining egg quality and performance in fish." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3563/.

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This thesis examined novel and previously utilised parameters of egg quality to determine and define reproductive success in farmed and wild salmonids. The effect of holding environment and inter-female variation on salmonid egg quality was also examined. Furthermore, two nutritional feed trials were undertaken to investigate whether organic Se, supplemented into salmonids broodstock diets, was vertically transferred to their eggs and what affect this dietary supplementation had on egg quality. Finally, the possibility that morphological and biochemical adaptations are present on the chorion of eggs from European whitefish (Coregonus lavaretus) was investigated in a resident Scottish population. Chapter 2 examined methods to determine egg quality using eggs from a single population of brown trout (Salmo trutta). Egg survival, provided a biologically relevant definition for egg quality, which was used throughout this study to assess the importance of selected egg quality parameters. Based on a review of the literature and the relationship between parameters of egg quality and egg survival rates, three determinants of egg quality were chosen for further examination. These were chorion breaking strength, elemental concentrations within the egg and the protein profile of the chorion. Brown trout broodstock from a single population were separated prior to spawning and exposed to two different holding units, ‘Ae system’ or ‘S.C.E.N.E. system’ at two sites. Eggs were stripped from females and 13 determinants of egg quality collected, analysed individually, combined by principle components analysis into an integrated egg quality score which was validated against egg survival. The multivariate egg quality score differed significantly between fish held in the Ae and S.C.E.N.E. systems. Egg survival, chorion breaking strength and Se chorion concentrations were higher in eggs produced by broodstock held in the S.C.E.N.E. system compared to those in the Ae system. Alternatively, chorion concentrations of P and K were higher in eggs from fish held in the raceway system. This data highlights the complex interactions between the holding environment and pre-ovulating fish and resultant egg quality. The variation in egg survival in individual Atlantic salmon (Salmo salar) reared in the same environment was assessed and used to examine the suitability of chorion measurements as parameters of egg quality. There was a significant difference in the egg survival rates between individual salmon. Results also show that there was also variation in egg survival, chorion breaking strength, chorion elemental concentrations and chorion protein concentrations and profiles between individual Atlantic salmon. Subsequent analysis of the data showed that there was no difference in these egg quality parameters between high and low egg survival rates. Furthermore, there was no correlation between egg survival and the chorion quality parameters recorded during this study. The results show that individual variation between fish is an important factor affecting egg quality. Broodstock Atlantic salmon were fed a standard commercial diet, with or without the addition of a supplemented nutritional mix, which included 0.5mg/kg of Sel-plex (organic Se). The Se content of the eggs and livers of each fish were assessed as was egg survival rates and proteomic analysis of the egg chorion. Concentrations of Se in the eggs of the individuals fed the supplemented diet were significantly higher than those fed the non-supplemented diet. However, the egg survival rate was also significantly lower in the supplemented group of fish. The assessment of the chorion protein profile and its proteomic structure was inconclusive. These results support the hypothesis that dietary selenium is vertically transferred to immature eggs during oocyte development. The lack of a linear relationship between Se egg concentrations and egg survival suggests that the lower survival rates of eggs from broodstock fed the supplemented diet in this trial was due to another nutritional component of the diet rather than the Se. Selenium enriched eggs from Atlantic salmon fed a supplemented diet and eggs from conspecifics fed a non-supplemented diet were tested for their ability to resist infection by Saprolegnia under incubation conditions similar to those used by the aquaculture industry. There was no significant difference in the presence/absence of infection, infection rate or survival between eggs produced by Atlantic salmon fed the supplemented and non-supplemented diet. Therefore, it was concluded that supplementation of broodstock diet does not alter the resistance of eggs to Saprolegnia. The presence of adhesive mechanisms on the surface of European whitefish eggs was examined from a population found within Loch Eck, Scotland. European whitefish eggs remain non-adhesive in a solution chemically similar to ovarian fluid, but become adhesive seconds after contact with water. Examination of the ultrastructure of the chorion showed that the morphology altered significantly after contact with water with nodule-like protuberances attached to connective filaments on the surface, present in water hardened but not non-water hardened eggs. Biochemical analysis also showed the presence of Chain A, RNase ZF-3e in the chorion of water hardened but not non water hardened eggs. Histochemical staining of the chorion showed that the externa, but not the interna stained positively for the presence of glycoproteins. Egg adhesive mechanisms allow European whitefish eggs to remain in optimal spawning grounds where factors such as mechanical damage, predation, desiccation and hypoxia are minimised.

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19

Ozen, Arda. "Role Of Hydrology, Nutrients And Fish Predation In Determining The Ecology Of A System Of Shallow Lakes." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607600/index.pdf.

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In this study, the hydrology and physical, chemical and biological variables of a shallow lake system including the Lakes Mogan and Eymir between 1997-2005 were evaluated. In Lake Eymir, a biomanipulation study was conducted between August, 1998 &ndash
December, 1999. Upon biomanipulation, Lake Eymir shifted to clearwater state with submerged vegetation domination during 2000-2003. However, in 2004, the lake shifted back to algae-dominated turbid state since the buffer mechanisms provided by submerged plants were absent. In the summer of 2005, fish kills were observed due to algal bloom. However, due to increasing hydraulic residence time in the lake, internal processes became more important for nutrients. Lake Mogan faces seasonal and interannual water level fluctuations. During the low water levels experienced in 2001 and 2005, which coincided with the high hydraulic residence times, the in-lake phosphorus amount was controlled by internal processes rather than external loading. Moreover, results revealed that hydrology and submerged plants were important in the ecology of Lake Mogan. Furthermore, the relationship between the phytoplankton, zooplankton and the environment in Lakes Eymir and Mogan, which was predicted via Canonical Corresponding Analysis, revealed that nutrients and water transparency were both important for plankton communities. Both the top-down and bottom up effects were valid in Lake Eymir, while only the bottom-up effect and submerged plants were important for Lake Mogan. Finally, the present study provided a good example for the submerged plant dominated clearwater state triggered by biomanipulation, and the impact of hydrology on the ecology of shallow lakes.

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20

Baró, Llàcer Cristina. "Aplicació de la citogenètica, hibridació in situ fluorescent (FISH) i cariotipat espectral (SKY) per a la caracterització genètica dels limfomes de la zona marginal esplènica." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/368220.

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El limfoma de la zona marginal esplènica (LZME) és una entitat reconeguda per la Organització Mundial de la Salut (OMS) amb característiques clíniques, morfològiques i immunofenotípiques ben establertes. Els LZME en contrast amb altres síndromes limfoproliferatives B (SLP-B) no presenta una lesió gènica característica associada. Les alteracions cromosòmiques complexes són freqüents i es troben en un 80% dels casos, i la deleció de 7q i la trisomia 3 són les anomalies més recurrents i considerades típiques en els LZME. A part dels cromosomes 3 i 7, els estudis més recents han descrit com a cromosomes més implicats en aquesta patologia el 1, 6, 8, 12 i 14. D’altra banda, pel que fa a les translocacions que afecten els gens de les immunoglobulines (Ig), només s’han publicat treballs de forma esporàdica concloen que es tracta d’un esdeveniment secundari en els LZME. L’objectiu d’aquest treball és un estudi citogenètic exahustiu dels LZME utilitzant les tècniques de citogenètica convencional, hibridació in situ fluorescent (FISH) i cariotipat espectral (SKY) per tal de detectar noves alteracions i marcadors genètics associats a aquesta patologia. Els resultats obtinguts confirmen l’elevada incidènica de la deleció de 7q i la trisomia 3 així com una alta implicació dels cromosomes 3, 6, 8, 9 i 12. La tècnica de l’SKY ha estat molt útil per a definir els cariotips complexes i juntament amb posterior l’aplicació de la tècnica de FISH hem pogut detectar noves translocacions cromosòmiques associades als LZME. Així mateix hem observat que les translocacions implicant els gens de les Ig són més habituals del que ha estat descrit fins ara en aquesta entitat i que molts cops queden emmascarades per la complexitat dels cariotips.
Splenic marginal zone lymphoma (SMZL) is a well recognized entity by the World Health Organization (WHO) that show clinical, morphological and immunophenotypical characteristic features. In contrast with other B-cell lymphoproliferative disorders, SMZL does not present an associated genetic aberration. Complex chomosomal alterations are obseved in about 80% of cases and 7q deletion and trisomy 3 are the most recurrent anomalies and are considered characteristic in SMZL. Apart from 3 and 7, recent studies described as the more frequent involved chromosomes in this entity chromosomes 1, 6, 8, 12 and 14. Regarding translocations involving immunoglobulin (Ig) genes, only few sporadic series has been published concluding that Ig translocations could be a secondary event in SMZL. The aim of this memory is to present a comprehensive study of SMZL performing conventional banding cytogenetic, fluorescence in situ hybridization (FISH) and spectral karyotyping (SKY) techniques to detect new aberrations and genetic markers associated with this entity. Our results confirm the high incidence of 7q deletion and trisomy 3 as well as a high implication of chromosomes 3, 6, 8, 9 and 12 in chromosomal alterations. SKY technique was very helpful to redefine complex karyotypes and combined with FISH techniques we could detect new chromosomal translocations associated to SMZL. In the same way, we could observe that translocations involving Ig genes are more common than has been described in this entity and in some cases these aberrations are masked by the complexity of the karyotypes.

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21

Durban, Llenas Mercè. "Estudi citogenètic del primer corpuscle polar d'oòcits d'hàmster i d'humans: diagnòstic genètic preimplantacional mitjançant l'anàlisi de primer corpuscle polar." Doctoral thesis, Universitat Autònoma de Barcelona, 2008. http://hdl.handle.net/10803/3813.

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Анотація:

El primer corpúsculo polar (1CP) es una célula que acompaña al ovocito maduro (MII) y se produce como consecuencia de la primera división meiótica en la gametogénesis femenina. Ambas células tienen dotaciones cromosómicas complementarias y por ese motivo el 1CP puede informar indirectamente de la dotación cromosómica del correspondiente ovocito, sin que este pierda su capacidad reproductiva. Este hecho permite que en el marco de un programa de fecundación in vitro (FIV) se puedan biopsiar los 1CP y diagnosticar indirectamente los ovocitos, evitando la transferencia de embriones procedentes de ovocitos afectos de la anomalía genética o cromosómica estudiada. Este procedimiento se conoce con el nombre de diagnóstico genético preimplantacional mediante análisis de 1CP (DGP-1CP) y permite detectar alteraciones genéticas o anomalías cromosómicas de origen materno, en concreto de primera división meiótica.
El objetivo general de este trabajo ha sido poner a punto un método de DGP-1CP mediante la técnica de análisis citogenético molecular conocida con el nombre de hibridación in situ fluorescente (FISH). Nos hemos centrado en la aplicación clínica del DGP-1CP en mujeres portadoras de translocaciones robertsonianas y mujeres portadoras de translocaciones recíprocas.
La metodología de obtención de extensiones cromosómicas de 1CP para realizar el análisis citogenético, se ha puesto a punto en un modelo animal (hámster, Mesocricetus auratus) y se ha adecuado a ovocitos humanos descartados de ciclos de FIV antes o después de su inseminación. Los Comités Éticos de la Universidad Autónoma de Barcelona (UAB) y del Centro de FIV correspondiente han aprobado el protocolo a seguir para realizar el presente estudio y los ovocitos han sido donados por pacientes cuando estaban llevando a cabo su ciclo de FIV.
Se han elaborado dos series de parejas 1CP-MII procedentes de ovocitos humanos no inseminados y descartados post inseminación, y se ha demostrado que las dotaciones cromosómicas son complementarias. La tasa de aneuploidia ha sido nula para ovocitos no inseminados y de un 5,1 % en ovocitos descartados por no mostrar signos de fecundación. La concordancia en parejas 1CP-MII en ovocitos no inseminados ha sido del 100 % y del 95,1 % en ovocitos descartados post inseminación.
También se han estudiado citogeneticamente, ovocitos inmaduros y cigotos humanos anómalos, descartados de ciclos de FIV después de su inseminación y donados por las pacientes. Tras el análisis citogenético mediante FISH, se ha demostrado que un 25,4 % de los complementos cromosómicos correspondientes a ovocitos inmaduros son euploides en estadio de metafase I y el resto son aneuploides. Se ha observado una mayor incidencia de aneuploidia en ovocitos inmaduros descartados post inseminación (88,2 %) que en ovocitos inmaduros no inseminados (47,1 %). En cuanto a los cigotos anómalos descartados de ciclos de FIV con inseminación convencional por tener más de dos pronúcleos, en todos ellos la ploidía correspondía al número de núcleos observado. Por el contrario los cigotos con un único pronúcleo pueden ser diploides (88,9 %) o haploides (11,1 %).
Aplicando el DGP-1CP a cinco mujeres portadoras de translocaciones robertsonianas y a cuatro mujeres portadoras de translocaciones recíprocas, y haciendo una revisión de los casos publicados hasta el momento, se ha hecho evidente que en mujeres portadoras de translocaciones robertsonianas la frecuencia de ovocitos cromosómicamente normales o equilibrados para la anomalía estudiada es del 60 % y en mujeres portadoras de translocaciones recíprocas es del 40 %. Se ha evidenciado una correlación estadísticamente positiva entre la frecuencia teórica de puntos calientes de recombinación y la incidencia observada de no disyunción de cromosomas homólogos en mujeres portadoras de translocaciones recíprocas con mínimo nuevo ovocitos diagnosticados.
In females, the particular characteristics of the gametogenesis allow the indirect characterization of the chromosome constitution of the gamete through the study of the first polar body (1PB) and these presents an opportunity for germ line analysis. The 1PB contents a chromosome set complementary to that of the oocyte. Thus, the 1PB can be analysed to obtain information on the chromosomal constitution of the corresponding oocyte, which is maintained in culture.
Preimplantation genetic diagnosis (PGD) using the first polar body is a modality of PGD that can be used when the woman is the carrier of a genetic disease or of a balanced chromosomal reorganization.
Here, we describe a procedure to obtain 1PB chromosome complements and our experience based on the analysis by fluorescent in situ hybridization (FISH) of unfertilized or fresh human oocytes and non-inseminated control human oocytes, by fixing separately the 1PB and the corresponding oocyte, and on the study of nine clinical cases of PGD using 1PB biopsy (five Robertsonian translocations and four reciprocal translocations).
The method was developed in an animal model (Syrian hamster). Human samples were donated by patients undergoing in-vitro fertilization (IVF) cycles. The Informed Consent Form and the protocol for the study were approved by the Ethics Committees of the Universitat Autònoma de Barcelona (UAB) and the IVF Centre.
In fresh oocytes, the chromosome morphology of the 1PB was well preserved, and the results were always concordant for each 1PB-oocyte pair. This indicates that the 1PB can be reliably used for the diagnosis of chromosome reorganizations. The frequency of aneuploidy was zero in fresh oocytes and 5.1 % in unfertilized oocytes.
Moreover, we describe the study of immature oocytes and abnormal zygotes from IVF cycles. We observed that 25.4 % of the chromosome complements from immature oocytes, were euploid in metaphase I, and the rest of complements were aneuploid. We observed more aneuploidy in immature oocytes discarded post insemination (88.2 %) than in immature oocytes non-inseminated (47.1 %). The ploidy of all zygotes with more than two pronuclei was concordant with the number of nuclei observed. Nevertheless, the zygotes with only one pronucleus were 88.9 % diploids and 11.1 % haploids.
Applying PGD-1PB to five female carriers of Robertsonian translocations and four carriers of reciprocal translocations, and reviewing the cases published, we observed that in women carriers of Robertsonian translocations robertsonianas and in women carriers of reciprocal translocations, the frequency of normal or balanced oocytes was 60 %, and 40 % respectively. In reciprocal translocation cases, published in the literature or studied by us, in whom at least nine oocytes had been diagnosed, a correlation has been found between the frequency of non-disjunction observed and the theoretical recombination rate.

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22

Salido, Galeote Marta. "Caracterització genètica del limfoma esplènic de la zona marginal (LEZM)." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/129387.

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La tesi recull els resultats obtinguts de la caracterització genética del linfoma de la zona marginal esplènic (LZME). Està presentat en format de tesi per articles, i inclou, en aquest ordre, els apartats de: Introducció, Hipòtesi i Objectius, Resultats, Discussió, Conclusions, Bibliografia i Annexos. La introducció resum la limfomagènesi i l’origen del limfòcits B, i detalla la anatomia dels òrgans involucrats en aquest procés. A continuació es fa una introducció a les neoplàsies de cèl·lules B madura i s’explica la classificació actual dels limfomes detallant les alteracions citogenètiques i moleculars d’aquest subgrup de neoplàsies. Més específicament es detallen les característiques clinico-biològiques del LZME, entitat que tracta aquesta tesi. Finalment, s’inclou un resum dels mètodes de detecció d’alteracions cromosòmiques i moleculars utilitzats per estudiar el càncer. Els resultats contenen un breu resum dels articles presentats en aquesta tesi i a més s’inclouen els articles publicats com a fruït d’aquest treball. A la discussió s’analitzen els resultats obtinguts i es comparen amb altres estudis de la literatura. Finalment, s’inclou també un capítol d’annexos que conté el material i mètodes emprat en aquesta tesi i les taules suplementaries d’un dels articles presentats.
This thesis contains the results of genetic characterization of splenic marginal zone lymphoma (LZME). It is presented as a compendium of publications, and includes, in this order, the sections: Introduction, Hypothesis and Objectives, Results, Discussion, Conclusions, Bibliography and Appendices. The introduction summarises the lymphomagenesis and the the origin of B lymphocytes, and details the anatomy of the organs involved in this process. Below there is an introduction to mature B-cell neoplasms explaining the current classification of lymphomas and detailing the cytogenetic and molecular alterations. More specifically explains the clinical and biological features of LZME. Finally, there is a summary of methods used for detecting chromosomal and molecular alterations in cancer. The results contain a brief summary of the papers included in this thesis and also included articles published as a result of this work. In the discussion section, the results are analysed and compared with other studies in the literature. Finally, there is a chapter appendices containing materials and methods used in this thesis and supplementary tables of one of the papers included.

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23

Saraoglu, Ece. "Impact Of Water Level Fluctuations And Fish On Macroinvertebrate Community And Periphyton Growth In Shallow Lakes - A Mesocosm Approach." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614220/index.pdf.

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A mesocosm experiment was conducted in Lake Eymir between June &ndash
September 2009 in order to elucidate the effects of water level changes and fish predation on periphyton growth and macroinvertebrates in semi-arid shallow lakes. Twenty four cylindrical enclosures, each with 1.2 m diameter, open to lake bottom and atmosphere, were placed at three different depths, i.e. 0.8 m (low water level, LW), 1.6 m (high water level, HW) and 2.3 m (however, data regarding the enclosures at 2.3 m were excluded in this study due to complications after fifth sampling) to simulate water level fluctuations. At each water level, four replicates were stocked with omnivorous&ndash
planktivorous fish (Tinca tinca and Alburnus escherichii) and the other four replicates were left fishless to observe the effect of fish predation. Ten shoots of submerged macrophytes (Potamogeton pectinatus) were planted and six polyethylene strips were hung in the water column in each enclosure to monitor macrophyte and periphyton growth. The mesocosms were sampled for physical, chemical and biological parameters weekly in the first month and fortnightly thereafter. Benthic macroinvertebrate samples were taken before the start, in the middle and at the end of the experiment with Kajak corer. Macrophytes were harvested after the last sampling for determination of dry weight, epiphyton, and the associated macroinvertebrates. All macroinvertebrate samples were sieved through 212 &mu
m mesh size before identification and counting. Over the course of the experiment, an average of 0.46 ±
0.03 m water level decrease in the mesocosms triggered submerged macrophyte growth in all LW enclosures, overriding the negative effects of fish predation. The results indicate that while fish predation pressure had negative influences on macroinvertebrate communities in terms of both abundance and richness, structural complexity created by dense vegetation in the LW mesocosms weakened the top-down effect of fish on macroinvertebrates by acting as a refuge in this semi-arid shallow lake.

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24

Lloveras, Caballé Elisabet. "Contribució de la citogenètica convencional i la hibridació in situ a l'estudi de les gammapaties monoclonals." Doctoral thesis, Universitat Autònoma de Barcelona, 2004. http://hdl.handle.net/10803/3662.

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Анотація:

El present treball de tesi es basa en l'estudi citogenètic de les gammapaties monoclonals. Les gammapaties monoclonals representen un grup de diverses patologies caracteritzades per un augment de la proliferació, maligne o no, d'un clon de cèl.lules plasmàtiques.
S'han estudiat 53 pacients afectes de gammapatia monoclonal de significat incert (GMSI), 54 pacients amb mieloma múltiple (MM) i 7 pacients amb leucèmia de cèl.lules plasmàtiques.
S'han aplicat les següents tècniques: la citogenètica convencional, el mètode MAC, la hibridació in situ fluorescent (FISH) i la tècnica de May-Grünwald Giemsa-FISH (FISH).
S'han presentat els resultats de tres articles:
-"The contribution of cytogenetics and in situ hybridization in the study of monoclonal gammopathies of undetermined significance" Cancer Genetics and Cytogenetics 132: 25-29, 2002.
-"Cytogenetic and FISH studies in 60 patients with multiple myeloma and plasma cell leukaemia" Cancer Genetics and Cytogenetics 148: 71-76, 2004.
-"Cytogenetic and fluorescence in situ hybridisation (FISH) studies in four cases of plasma cell leukaemia (PCL)" Cancer Genetics and Cytogenetics 121: 163-166, 2000.
I un annex de tres articles més:
-"May-Grünwald-Giemsa- Fluorescence in situ hybridization (MGG-FISH) technique applied to a plasma cell leukemia" Haematologica 84 (6): 568-569, 1999.
-"A new case of Turner syndrome associated with multiple myeloma" Cancer Genetics and Cytogenetics 171(1): 80-81, 2000.
-"Técnicas de hibridación in situ (HIS). Fundamento y aplicaciones en neoplasias hematológicas" Sangre 44 (4): 261-267, 1999.
Les conclusions que es van obtenir van ser les següents:
1. Els estudis citogenètics en GMSI no són informatius degut a que la cèl.lula que entra en divisió no és la cèl.lula plasmàtica. La FISH sobre el total de cèl.lules de moll d'os és fiable i permet detectar alteracions encara que possiblement enmascara alguns pacients amb aneuploidies.
2. Els pacients amb GMSI tipus IgA s'associen de forma estadísticament significativa a la presència d'una monosomia 18.
3. La citogenètica convencional en MM només detecta alteracions en un 50% dels casos. Les alteracions més freqüents són les alteracions al cromosoma 1, reordenaments a 14q32 i la monosomia 13.
4. L'associació entre monosomia 18 i IgA no s'ha confirmat.
5. El 100% dels pacients amb LCP presenten alteracions citogenètiques, freqüentment amb hipodiploidia i monosomia 13.
6. La técnica MGG-FISH permet determinar en quina cèl.lula es troba l'alteració citogenética.
The present study is based in the cytogenetic study of monoclonal gammopathies. Monoclonal gammopathies are characterized by the presence of a clone of plasma cells in the bone marrow.
Samples were collected from 53 patients with monoclonal gammopathy of undetermined significance (MGUS), 54 patients with multiple myeloma (MM) and 7 patients with plasma cell leukemia.
We applied the following techniques: conventional cytogenetics, the MAC method, fluorescence in situ hybridization (FISH) and May-Grünwald-Giemsa-FISH (MGG-FISH) technique.
Results were published three papers:
-"The contribution of cytogenetics and in situ hybridization in the study of monoclonal gammopathies of undetermined significance" Cancer Genetics and Cytogenetics 132: 25-29, 2002.
-"Cytogenetic and FISH studies in 60 patients with multiple myeloma and plasma cell leukaemia" Cancer Genetics and Cytogenetics 148: 71-76, 2004.
-"Cytogenetic and fluorescence in situ hybridisation (FISH) studies in four cases of plasma cell leukaemia (PCL)" Cancer Genetics and Cytogenetics 121: 163-166, 2000.
And another three papers were included in an annex:
-"May-Grünwald-Giemsa- Fluorescence in situ hybridization (MGG-FISH) technique applied to a plasma cell leukemia" Haematologica 84 (6): 568-569, 1999.
-"A new case of Turner syndrome associated with multiple myeloma" Cancer Genetics and Cytogenetics 171(1): 80-81, 2000.
-"Técnicas de hibridación in situ (HIS). Fundamento y aplicaciones en neoplasias hematológicas" Sangre 44 (4): 261-267, 1999.
Conclusions were:
1. Cytogenetic studies in MGUS are not informative because the cell that we studied is not the plasma cell. FISH applied in the totality of the bone marrow cells is trust worthy but probably, in some of our cases, the aneuploid plasma cells cannot be detected because their low percentage.
2. Patients with MGUS and IgA type are associated with the presence of monosomy 18.
3. Conventional cytogenetics in MM can detect abnormal karyotypes in 50% of cases. The more frequent abnormalities are rearrangements in chromosome 1 and 14q32 and monosomy 13.
4. The association of monosomy 18 and IgA was not observed in our series of MM.
5. The 100% of patients with PCL presented cytogenetic abnormalities, frequently hypodiploidy and monosomy 13.
6. The MGG-FISH technique permits to determine which cell presents the cytogenetic abnormality.

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25

Tuba, Bucak. "Determining The Roles Of Water Level And Fish Predation On Submerged Plant Growth In Shallow Lakes Using Mesocosm Experiment." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612995/index.pdf.

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Анотація:

Four-month mesocosm experiment from June 1st to September 25th, 2009, was conducted to determine the effect of water level dierence in combination with fish predation pressure, on submerged macrophyte development, in an eutrophic shallow lake. Effect of water level fluctuation was simulated by placing enclosures to the different water depths that included 0.8 m, 1.6 m and 2.3 m on Lake Eymir. These enclosures having a cylindirical shape and 1.2 m diameter, were open to sediment and atmosphere interaction. The highest water level mesocosms were cancelled after fifth sampling due to rapture in the bags, hence this thesis does not include the results of 2.3 m. At each depth, half of the enclosures were stocked with planktivo-omnivorous fish (Tinca tinca, Alburnus spp.) which are natural fauna of Lake Eymir. Before stocking of fish, ten shoots of Potamageton pectinatus were added to all of the enclosures in order to observe submerged macrophyte development. Sampling for physico-chemical parameters, zooplankton, chlorophyll a, PVI% and periphyton was conducted weekly for the first five weeks, last six samplings were done biweekly. Macrophyte harvesting for dry weight estimation was done at the end of the experiment. Throughout the experiment water level decreased 0.41 ±
0.06 m in each enclosures. Water level was so critical for macrophyte development that no significant macrophyte growth was observed in enclosures located at 1.6 m (HW). However, fish predation did not prevent the growth of macrophyte in enclosures located at 0.8 m (LW) but it was important in HW enclosure for affecting water clarity. Fish predation affected chlorophyll a, zooplankton and nutrient concentrations and the effect was mostly pronounced at LW enclosures. They had high chlorophyll a and nutrient concentrations but it did not repress macrophyte growth as in temperate lakes. Despite high water clarity in HW fishless enclosures, very low macrophyte biomass may be attributed to enhanced periphyton development. Zooplankton community shifted to small sized ones under fish predation while fishless enclosures had higher zooplankton /phytoplankton ratio for each depth. Hence, regarding these results it can be stated that decrease in water level can compensate the negative effects of fish predation on macrophyte growth in warm Mediterranean lakes.

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26

Karapinar, Burcu. "Role Of Hydrology, Sewage Effluent Diversion And Fish On Mass Balance Of Nutrients In A System Of Shallow Lakes Mogan And Eymir, Turkey." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606542/index.pdf.

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In this study, annual total phosphorus (TP) budget and dissolved inorganic nitrogen (DIN) load were constructed for Lakes Mogan and Eymir for the period of eight years from 1997 to 2004 and the period of ten years covering from 1993 to 1995 and 1997 to 2004, respectively. Lake Mogan experienced seasonal and interannual water level fluctuations. Low water level experienced in 2001 led to decrease in the in-lake TP amount whereas 2-fold increase in the in-lake DIN amount was recorded. Also, high hydraulic residence time resulted in high TP and DIN amount in the lake. Increase in hydraulic residence time was due to management of the lake level. It seems that this practice deteriorates the water quality of Lake Mogan. In Lake Eymir, sewage effluent diversion undertaken in 1995 resulted in 2-fold and 11-fold decrease in TP and DIN amounts in the lake, respectively. High biomass of carp and tench were halved through selective removal during 1998-1999. A 2.5-fold and 1.5 fold decrease in the in-lake TP and DIN amounts, respectively, were recorded after the biomanipulation. In low water level years, the in-lake TP increased and the in-lake DIN amounts were high despite the fact that TP and DIN loads via inflows were significantly low. Therefore, the results showed that the in-lake phosphorus and nitrogen amount were controlled by internal processes rather than external loading in the years with low water levels which coincided with the high hydraulic residence times.

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27

Zamora, Plana Lurdes. "Caracterització Biològica de la Trombocitemia Essencial i la Policitemia Vera." Doctoral thesis, Universitat Autònoma de Barcelona, 2005. http://hdl.handle.net/10803/3667.

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Анотація:

El concepte de síndromes mieloproliferatives cròniques (SMPC) engloba un conjunt d'entitats hematològiques amb característiques clíniques i evolutives molt similars i d'etiopatogènia probablement comú. Es tracta de processos caracteritzats per l'expansió clonal d'una cèl·lula mare (stem cell) pluripotent, que dóna com a resultat una hipercel·lularitat medul·lar amb predomini d'una o més línies que arriben a diferenciar-se en elements madurs. Totes les SMPC es troben subjectes a evolució clonal però en un grau força variable: un 90% d'evolució a leucèmia aguda en la leucèmia mieloide crònica front un 1-2% a la trombocitèmia essencial. Les SMPC clàssiques comprenen quatre entitats: la leucèmia mieloide crònica (LMC), la mielofibrosi idiopàtica (MI), la policitèmia vera (PV) i la trombocitèmia essencial (TE). Aquesta tesi pretén caracteritzar biologicament millor la PV i la TE.
La PV és el resultat de la proliferació anormal d'una cèl·lula mare pluripotent, que dóna lloc a una hemopoesi clonal d'hematies, granulòcits i plaquetes, amb predomini d'hiperplàsia eritroide sobre la resta de línies hemopoètiques.
La TE és una SMPC caracteritzada per un increment persistent de la xifra de plaquetes i per una hiperplàsia megacariocítica en la medul·la òssia.
Un dels criteris diagnòstics majors de la PV i majoria dels criteris diagnòstics de la TE són criteris d'exclusió. Aquest fet fa que constantment s'estiguin buscant nous biomarcadors que ajudin al diagnòstics d'aquestes patologies. Les tècniques que s'han utilitzat en aquestes tesi amb aquest propòsit han sigut:
1. Citogenètica convencional:
- PV: Al moment del diagnòstic entre el 13-18% dels pacients presenten un cariotip alterat mitjançant tècniques de citogenètica convencional. Les alteracions més freqüents són: del(20q) (25%), trisomia 8 (16%), trisomia 9 (16%) (tampoc era rar trobar les dues trisomies 8 i 9 juntes en el mateix pacient), duplicacions de bandes inespecífiques d'1q o trisomies d'1q (10%), seguit per del(13q), del(11q), del(7q), del(5q) i trisomia 21.
- TE: Al moment del diagnòstic entre el 5% i 10% dels casos presenten alteracions cromosòmiques. Entre les alteracions citogenètiques més descrites en la TE trobem les delecions dels braços llargs dels cromosomes 20 (del(20q)) i 13 (del(13q)) i les trisomies 8 i 9.
2. Hibridació in situ fluorescent:
- PV: El percentatge de pacients amb alteracions cromosòmiques que es detecten mitjançant la tècnica de FISH varia entre 14.3% i 71.5% en funció de cada sèrie.
- TE: El percentatge de pacients amb alteracions cromosòmiques que es detecten mitjançant la tècnica de FISH varia entre 15% i 55% en funció de cada sèrie.
3. Estudi de clonalitat mitjançant el gen HUMARA:
- PV: El percentatge de clonalitat entre les pacients afectes de PV oscil·la entre el 41% i el 73%.
- TE: El percentatge de clonalitat entre les pacients afectes de TE oscil·la entre el 18.7% i el 68%.
La tècnica més útil com a nou biomarcador ha estat l'estudi de clonalitat mitjançant el gen HUMARA. Ara bé, la recerca constant de possibles biomarcadors (ex. PRV-1, JAK2...) poden superar la eficacia d'aquesta tècnica.
Essential thrombocythemia (ET) and polycythemia vera (PV) are chronic myeloproliferative disorders (MPD) arising from the clonal expansion of a pluripotential stem cell. Specific genetic lesions have not been recognized for both disorders, so, diagnostic criteria still are based on the presence or absence of particular clinical and laboratory features
In recent years, there have been attempts to find new positive criteria that could help in the diagnosis of ET and PV, such as spontaneous in vitro colony formation of erythroid and megakaryocytic progenitors, conventional cytogenetics, fluorescence in situ hybridization techniques and analysis of X-chromosome inactivation patterns (XCIPs). This thesis wants to better characterize PV and ET. For this propose it has been used the following methodologies:
1. Conventional Cytogenetics:
- PV: At diagnosis between 13-18% of patients has an abnormal karyotype with conventional cytogenetics methodologies. The most frequent abnormalities are del(20q) (25%), trisomy 8 (16%), trisomy 9 (16%) (we can also find both alterations together in the same patient), duplications of unspecific bands from 1q or trisomy 1q (10%), del(13q), del(11q), del(7q), del(5q) and trisomy 21.
- TE: At diagnosis between 5-10% of patients has an abnormal karyotype with conventional cytogenetics methodology. The most frequent abnormalities are del(20q)), del(13q) and trisomy 8 and 9.
2. Fluorescent in situ hybridization:
- PV: The percentage of patients with abnormalities detected by FISH goes from 14.3% to 71.5% depending on the series.
- TE: The percentage of patients with abnormalities detected by FISH goes from 15% to 55% depending on the series.
3. Clonality study with HUMARA gene:
- PV: The percentage of clonality between patients goes from 41% to 73%.
- TE: The percentage of clonality between patients goes from 18.7% to 68%.
The most useful technique as a biomarker has been the clonality study with the HUMARA gene. But the constant investigation of new possible biomarkers (ex. PRV-1, JAK2...) could be even more useful than this one.

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28

Akkas, Sara Banu. "The Effect Of Ecotoxicants On The Aquatic Food Web And Prey-predator Relationships." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610823/index.pdf.

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There is considerable need for higher-tier aquatic risk assessment and information on toxicant-induced molecular alterations in lower aquatic invertebrates. Thus the current study&rsquo
s priorities were two-fold: a novel approach utilizing higher-tier ecotoxicity bioassay-guided ATR-FTIR (Attenuated Total Reflectance Fourier Transform Infrared) spectroscopy to better understand the impact of the presence of fish predation pressure &ndash
mimicked by predator-exuded info-chemicals &ndash
on cypermethrin or salinity toxicity to Daphnia pulex &ndash
key-stone species in lake ecosystems &ndash
and ultimately better assess toxicant-induced alterations at both organismal and molecular levels. This approach indicates that even low concentrations of cypermethrin/salinity had significant molecular and organismal effects on daphnids. Fish kairomone acted as a major factor affecting toxicant severity, interacting antagonistically below a threshold and synergistically above. Moreover, molecular ATR-FTIR spectroscopic results, clearly consistent with organismal responses, showed that both cypermethrin and salinity lead to decreased contributions of lipid and proteins to the investigated daphnid systems. It is further suggested that the action mechanism of the fish-exuded kairomone occurs via the lipid metabolism of Daphnia. Hence, infrared spectroscopic results enabled detection of early molecular alterations, whose effects might not always be observable at the organismal level. The results of this study clearly indicate that the simplistic nature of standard ecotoxicology tests hinders a precise judgment of threats imposed by chemicals of interest. Furthermore, it has been shown that ATR-FTIR spectroscopy has considerable potential for studies on daphnid responses to varying environmental conditions. Thus, this study presents a starting point for increasing the environmental realism of aquatic risk assessment.

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29

Lopez, Michele. ""Breaking the lawn chair, skinning the fish" : Categorization and Gender Differences in Slang Use in the TV Series Sex Education." Thesis, Södertörns högskola, Engelska, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-45838.

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Анотація:

This essay, entitled “Breaking the lawn chair, skinning the fish” - Categorization and Gender Differences in Slang Use in the TV Series Sex Education, claims that slang is part of our everyday language use and it can be found even on TV nowadays. In fact, contemporary TV series often portray a language use that includes informal language and slang expressions and words. This study aims to categorize slang expressions and words and identify gender differences in slang use in the British TV series Sex Education. By integrating quantitative and qualitative methods, the study contrasts Eble’s (1996) and Zotevska’s (2014) categorizations of slang and highlights gender perspectives on language use. First of all, the results show that Eble’s categorization proves to be incomplete to categorize the slang expressions in Sex Education. Furthermore, Zotevska’s categorization shows that a pervasive presence of taboo words and expressions is found in slang usage, whereas proper slang and pragmatic markers constitute a limited amount of the total. Secondly, the results highlight male characters as predominant slang-users. The collected data also indicate an increased presence of slang expressions and words in female speech, as a result of their emancipation and higher levels of participation in Western Societies.

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30

Escalona, Mena Ariadna. "Aplicació de les tècniques de citogenètica molecular per a l'establiment d'associacions genotip-fenotip." Doctoral thesis, Universitat Autònoma de Barcelona, 2010. http://hdl.handle.net/10803/3839.

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Анотація:

Avui dia encara són moltes les persones que consulten els Serveis de Genètica Clínica per presentar malformacions congènites i/o retard mental. En aquests casos, cal establir un bon diagnòstic genètic així com realitzar una bona exploració clínica, ja que la comparació dels trets presents en pacients amb alteracions cromosòmiques idèntiques o similars permetrà detectar les anomalies clíniques comunes i, per tant, establir les correlacions genotip-fenotip.
En aquest treball s'han analitzat 145 mostres de pacients que presentaven malformacions congènites i/o retard mental i infertilitat i amb un cariotip normal o anormal sense acabar de ser caracteritzat per citogenètica convencional. Les 145 mostres s'han dividit en cinc grups: GRUP A: 90 pacients amb cariotip normal i quadre clínic; GRUP B: 8 barons 46,XX; GRUP C: 10 pacients portadors d'anomalies cromosòmiques "aparentment" equilibrades; GRUP D: 18 pacients amb monosomies o trisomies parcials i el GRUP E: 19 pacients amb cromosomes marcador.
S'han aplicat tècniques d'extracció d'ADN, de cultiu cel·lular, i d'obtenció d'extensions metafàsiques per analitzar les mostres. Amb l'ADN extret, s'han aplicat les tècniques de MLPA (P036B, P070, P106-B1), de CGH/HR-CGH (Nick translation kit) i d'aCGH (qChip Post de 60000 clons i xip de 19000 clons). A partir de les extensions metafàsiques, s'han aplicat diferents tècniques de FISH: locus específica, pintat cromosòmic, sondes de cromosomes artificials de bactèries, multipintat, multicolor centromèrica i de bandeig multicolor.
L'aplicació d'una bateria de tècniques de citogenètica molecular ha permès confirmar la presència d'anomalies cromosòmiques al 7.8 % dels pacients del grup A i s'ha proposat un protocol d'actuació en un laboratori de diagnòstic clínic per aquest tipus de pacients. Respecte al grup B, s'ha evidenciat l'existència d'heterogeneïtat de material corresponent a la regió pseudoautosòmica XPAR1 que podria contribuir a la variabilitat fenotípica que presenten els barons 46,XX,SRY+. Pel que fa als resultats obtinguts al grup C, s'ha caracteritzat amb més precisió l'anomalia cromosòmica al 55% dels casos. L'estudi del grup D ha permès caracteritzar l'origen cromosòmic implicat en les diferents anomalies en tots els casos. A més, s'ha confirmat l'anomalia detectada per CGH/HR-CGH al 78 % dels casos i la FISH amb sondes BAC ha permès redefinir els punts de trencament implicats en l'anomalia cromosòmica en tots els casos en què ha estat aplicada. Finalment, respecte al grup E, la combinació de diferents tècniques de citogenètica molecular ha permès una identificació de l'origen del sSMC al 94.7% dels pacients. S'ha proposat també un protocol d'actuació en un laboratori de diagnòstic clínic i s'ha vist que l'origen cromosòmic més comú del marcador ha estat el cromosoma 15 (10 casos), seguit del cromosoma 8 (3 casos), 13/21 ó 14/22 (2 casos) i dels cromosomes 2 , 7 , 9 i 22 (1 cas).
Paral·lelament, l'anàlisi dels punts de trencament implicats en les diferents anomalies cromosòmiques estudiades , ha revelat que la seva distribució al genoma no és a l'atzar, ja que la majoria es localitzen en les bandes clares (un 61%), que corresponen a regions amb major densitat gènica. També, que majoritàriament els punts de trencament coincideixen amb bandes riques en duplicacions segmentàries (DSs) i en regions on s'han descrit variacions en el número de còpies (CNVs) (un 83% i un 94% respectivament). A més a més, cap de les regions CNVs implicades als casos que presentaven un fenotip normal havia estat associada a alguna síndrome clínica a la literatura, mentre que entre el 18% i el 25% de les regions CNVs implicades en els punts de trencament dels pacients amb anomalies cromosòmiques i fenotip alterat, sí que havien estat associades a síndromes clíniques segons la literatura.
Nowadays there are many people who consult The Genetic Clinical Services because of congenital malformations and/or mental retardation. In these cases, it is essential to make a proper genetic diagnosis as well as a good clinical exploration in order to establish accurate genotype-phenotype associations.
145 samples from patients presenting congenital malformations and/or mental retardation and infertility with a normal or an abnormal karyotype have been studied in this work. These samples have been classified in 5 different groups. Group A: 90 patients with a normal karyotype and clinical manifestations; Group B: 8 46,XX males; Group C: 10 patients with apparently balanced chromosomal abnormalities; Group D: 18 patients with partial monosomies or trisomies and Group E: 19 carriers of supernumerary marker chromosomes (sSMC).
DNA extraction protocols, cell culture and metaphase spreads have been applied in order to analyze all these samples. MLPA (P036B, P070, P106-B1 kits), CGH/HR-CGH (Nick translation kit) and/or aCGH (qChip Post of 60000 clones and a chip of 19000 clones) techniques were applied from extracted DNA. To confirm these results, different FISH techniques (MFISH, cenMFISH and subcenMFISH) have been used over metaphase spreads.
The use of a variety of molecular cytogenetic techniques has allowed the identification and confirmation of chromosomal anomalies in 7.8% of the patients from group A. Besides, a protocol of proceedings has been suggested to use in private clinical laboratories in such cases. In reference to group B, this battery has shown that the pseudoautosomal region XPAR1 can be very heterogeneous in these patients, and this heterogeneity might contribute to the phenotypic variability of 46,XX,SRY+ males. Referring to group C, a more accurate identification of the chromosomal anomaly has been obtained in 55% of cases. The study of patients from group D has allowed the identification of the chromosomal origin of the anomaly in all the cases. The CGH/HR-CGH results have been confirmed in 78% of these patients. Besides, FISH with BAC probes has demonstrated to be a very useful tool in order to identify the break points involved in all the chromosomal anomalies analyzed. Finally, in reference to group E, this battery of techniques has allowed the identification of the origin of SMC in 94.7% of cases. Another protocol of proceedings has been suggested to use in private clinical laboratories in such cases. The marker chromosomes more frequently analyzed in this work derived from chromosomes 15 (10 cases), 8 (3 cases), 13/21 or 14/22 (2 cases) and 2, 7, 9 and 22 (1 case each).
On the other side, the analysis of all the break points involved in the chromosomal anomalies studied in this series of patients has revealed that their distribution along the human genome is not random, since the 61% were located in white bands, which are gene-rich. Besides, they do also tend to locate in DSs-rich bands and in regions where CNVs have been described (83% and 94% respectively). Furthermore, none of the CNVs involved in phenotypic normal cases had been described as pathogenic previously , whereas over the 18%-25% of the CNVs identified at the break points in patients with an abnormal phenotype had been associated with clinical syndromes according to the literature.

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31

Duran, Puig Assumpta. "Alteracions cromosòmiques radioinduïdes: Estudis en irradiacions parcials i retrospectius." Doctoral thesis, Universitat Autònoma de Barcelona, 2010. http://hdl.handle.net/10803/48531.

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La dosimetria biològica és un camp que s’ha desenvolupat dins la radioprotecció i permet estimar la dosi d’una exposició a radiacions ionitzants en casos en que no es coneix o no és prou fiable la dosimetria física. En dosimetria biològica, la metodologia més establerta per estimar la dosi d’una exposició a radiacions es basa en obtenir la freqüència d’una determinada alteració cromosòmica i, extrapolar‐la a una corba dosi‐efecte prèviament elaborada. Hi ha diversos factors que poden fer variar la freqüència de les alteracions cromosòmiques, entre aquests hi ha el cas de les irradiacions parcials, que es dona quan una irradiació només afecta una part del cos, i no la seva totalitat. En aquests casos si és realitza dosimetria biològica l’estimació de la dosi serà menor de la que en realitat és. Per tal de simular irradiacions parcials és va irradiar sang perifèrica a 2, 3, 4 i 5 Gy amb raigs X, i es va barrejar amb sang no irradiada per tal de tenir diferents percentatges de sang irradiada (87,5, 75, 50, 25 i 12,5%). Es va realitzar l’anàlisi mitjançant tècniques de FISH, pintant els cromosomes 1, 4 i 11 conjuntament amb tots els centròmers. Les alteracions cromosòmiques detectades es van expressar en nomenclatura PAINT, PAINT modificada i convencional. Es van utilitzar el test u i el test s (basat en el model de Poisson inflat en el zero) per avaluar la sobredispersió causada per les cèl∙lules no irradiades. Es va estimar la dosi per a cada tipus d’alteració considerada amb el mètode Dolphin i les corbes dosi‐efecte prèviament elaborades (usant les mateixes sondes cromosòmiques). Només es va detectar sobredispersió a dosis altes i a percentatges de sang irradiada baixos. Els dos mètodes usats per detectar desviacions de la distribució de Poisson van mostrar resultats molt similars. El total d’alteracions aparentment simples van ser el tipus d’alteració que l’estimació de la dosi va ser més propera a la dosi real que es va irradiar. Les tècniques de FISH utilitzades van tenir la mateixa eficiència detectant dicèntrics com translocacions. Comparant els resultats obtinguts amb tècniques de FISH amb els obtinguts analitzant dicèntrics amb tinció uniforme, amb aquest últim mètode s’obtenen millors resultats tant en la detecció de d’irradiacions parcials com en l’estimació de la dosi. Un altre factor que influeix en l’estimació d’una dosi és el temps transcorregut després d’una irradiació, ja que no totes les alteracions cromosòmiques presenten la mateixa estabilitat al llarg del temps. Per avaluar quines alteracions són més útils alhora d’estimar la dosi d’una exposició anterior (dosimetria biològica retrospectiva) es va fer un estudi utilitzant com a model la línia cel∙lular limfoblastoide Jurkat de cariotip normal i estable. Es van irradiar cèl∙lules Jurkat en G0 a dosis de 0,2, 2 i 2Gy amb raigs X, un cop irradiades es van mantenir en cultiu durant tres setmanes i es van extreure alíquotes a diferents temps. Les alteracions cromosòmiques induïdes es van analitzar mitjançant tècniques de pintat dels cromosomes 1, 4 i 11 conjuntament amb tots els centròmers per avaluar la persistència de translocacions i dicèntrics, i la tècnica d’mFISH per avaluar la freqüència, la complexitat, la participació de cada cromosoma de les alteracions radioinduïdes i les associacions cromosòmiques preferencials en les mostres inicials i finals en el cultiu control i en els irradiats a 2 i 4 Gy. En l’estudi realitzat amb pintat cromosòmic a totes les dosis la freqüència (x100) de dicèntrics i d’alteracions complexes van disminuir de forma ràpida fins arribar a valors popers a 0. La freqüència (x100) de translocacions es va mantenir força constant als cultius irradiats a 0,2 i 2 Gy mentre que als cultius irradiats a 4 Gy es va observar un descens que en les mostres inicials era pronunciat i en les finals era suau. La tècnica d’mFISH va mostrar que són les alteracions simples incompletes les que desapareixen al llarg del temps i que el grau de complexitat de les alteracions cromosòmiques augmenta amb la dosi i disminueix amb el temps post‐irradiació. No es van detectar desviacions respecte a la participació a l’atzar de cada cromosoma quan es van considerar les alteracions tipus intercanvi, però si que es van detectar quan es van considerar el total de alteracions cromosòmiques radioinduïdes. Es van detectar diferencies significatives en associacions cromosòmiques preferencials en la mostra inicial i en la final del cultiu de cèl∙lules Jurkat.
Biological dosimetry is is a field that has developed within the radioprotection to estimate the dose of ionizing radiation exposure in cases that physical dosimetry is not enough reliable or is unkown. In biological dosymetry, the more established methodology for estimating the dose of radiation exposure is based on extrapolate the frequency of a specific chromosomal alteration in a dose‐effect curve previously prepared. There are several factors that can vary the frequency of chromosome aberrations among these is the case of partial body irradiations, which occurs when radiation affects only a part of the body. In those cases the dose will be underestimated. In order to simulate partial body dose irradiations peripheral blood samples were irradiated at 2, 3, 4 and 5 Gy of X‐rays, and mixed with non‐irradiated blood to obtain the following percentages of irradiated blood: 87.5, 75, 50, 25 and 12.5. FISH painting was performed using whole chromosome painting probes for chromosomes 1, 4, and 11 in combination with a pancentromeric probe. Chromosome aberrations were recorded using the PAINT nomenclature, and later converted to the modified PAINT and conventional nomenclature. The u‐test was initially used to evaluate the expected overdispersion due to the presence of unexposed cells, but a test based on the zero‐inflated Poisson model (s‐test) is also proposed. Dose‐estimations for the different types of chromosome aberrations were calculated by Dolphin’s method and using the FISH dose‐effect curves previously obtained using the same whole‐chromosome probes. The expected overdispersion due to the presence of unirradiated cells was only detected at high doses and low percentages of irradiated blood. The two methods used to detect the deviation from the Poisson distribution showed a similar ability. Dose estimations for the irradiated fraction were closer to the real values for total apparently simple aberrations. In general, using FISH techniques similar results were obtained for dicentrics and translocations. In comparison to solid‐stain dicentric analysis, the use of FISH painting techniques is less suitable to detect partial irradiations, and for dose estimation assessment. Another factor in the estimation of a dose is the time elapsed after irradiation, as not all chromosome aberrations have the same stability over time. To evaluate which aberrations were more useful to estimate the dose for a retrospective exposure an irradiated cell line was studied. A follow‐up study on the persistence of the different types of chromosome aberrations was carried out. The lymphoblastoid cell line Jurkat was irradiated at 0.2, 2 and 4 Gy of X‐rays. After irradiation, the cultures were maintained for three weeks and samples were harvested at different times. Chromosome aberrations were detected using two FISH techniques: painting of chromosomes 1, 4 and 11, to assess the persistence of translocations and dicentrics, and mFISH to evaluate the frequency, the complexity, the chromosome involvement on the radiation‐induced chromosome aberrations and the preferential chromosome‐chromosome associations in the initial and final samples in the control and irradiated cultures at 2 and 4 Gy. In the study performed with painted technique, in all doses, the frequencies (x100) of dicentrics decreased clearly in the successive samples until values near zero. The frequencies (x100) of translocations, at 0.2 and 2Gy, were relatively constant until the last sample, whilst at 4Gy there was an initial steeped decrease in the first samples followed by a slight decrease in the last ones. The technique mFISH showed that simple incomplete aberrations disappear over time and the complexity of chromosome aberrations increases with dose and decreases with post‐irradiation time. The chromosome involvement was random for radiation‐induced exchange aberrations and non‐random for total aberrations. Preferential chromosome‐chromosome associations were observed in the initial and final samples in the Jurkat cell line.

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32

Buyukcan, Mehmet. "Preservation And Shelf Life Extension Of Shrimps And Mussels By High Hydrostatic Pressure(hpp)." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/3/12607290/index.pdf.

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Shrimp and mussel samples were cleaned, washed and exposed to steam before freezing. HHP treatment was performed at combinations of 200, 220 and 250 MPa at 25, 30, 40 and 50°
C for 10 and 20 minutes. Microbial analysis were performed by analyzing the effect of treatments on the microbial reduction in the samples. Based on the results of the microbial reduction, the best combinations of HHP treatments were determined as 250 MPa, 50°
C, 10 minute for shrimps and 220 MPa, 50°
C, 10 minute for mussels where total microbial inactivation was achieved. Storage analysis was performed on the samples, treated at the selected HHP combinations and stored at room (25°
C) and refrigeration temperatures (4°
C). For the storage analysis, variations in Total Volatile Bases (TVB-N) and pH were measured. According to the results evaluated, shelf-life of the shrimps were detected as 10 and 16 days for storage at room and refrigeration temperature, respectively as compared to 4 days of untreated sample at 4oC. Similarly shelf-life for the mussel samples were obtained as 12 days for storage at room and 18 day for storage at refrigeration temperature as compared to 4 days of untreated sample at 4oC. HHP-at the studied parameters for shrimps and mussels- can be offered as an alternative method for the preservation of shell-fish instead of conventional frozen food technology, which is currently used in the industry, since it gives the opportunity to handle the samples at lower temperatures for the post-production period resulting in both reduction of energy required and operational costs without sacrificing from the quality as measured by microbial reduction, TVB-N and pH.

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33

Miró, Pastó Alexandre. "Fish as local stressors of Pyrenean high mountain lakes: Arrival process and impact on amphibians and other organisms." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/384835.

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Pyrenean high mountain lakes are naturally fishless due to natural barriers that have prevented the natural colonisation of fish species from lower streams. However, there have been numerous trout introductions to such ecosystems, both in historical and recent periods. Differing from other high mountain regions, some high mountain lakes of the Pyrenees were exploited traditionally for trout cultivation. This activity started at least centuries ago and lasted until 1950s, affecting approximately 25% of the lakes. Since 1950, and similar to other high mountain regions, a wave of modern introductions with exotic species has affected among 35% and 85% of the lakes depending on the valley. In recent decades, minnows have also been introduced, being present in 2000 in 27% of Pyrenean high mountain lakes, as a result of recreational fishing with livebait. The first part of the thesis was intended to provide an objective description of the fish introduction process in the Pyrenees. For that purpose we collected data on trout and minnow occurrence from 520 high mountain lakes >0.5 ha of the southern Pyrenees and quantified, by generalized additive models, which particular factors either environmental or anthropogenic, best explained their present distribution and as a result their lake conservation status. The distribution of Salmo trutta in the southern slope of the Pyrenees was best explained by both, anthropogenic factors and lake characteristics, while only anthropogenic factors linked to recreational fishing were associated with the distribution of the exotic trout Salvelinus fontinalis and Oncorhynchus mykiss. For the case of minnow occurrence, previous presence of trout in the lake was the most explanative variable, confirming its association with recreational fishing using them as livebait. Trout and minnow introductions can cause large ecological problems and ecosystem alterations in high mountain lakes and ponds, since both trout and minnows occupy the top of a lake’s food chain. In the second part of the thesis, we sampled 1736 Pyrenean high mountain lakes and ponds at different levels of intensity and investigated the effects of introduced fish on indicator faunal groups such as amphibians and conspicuous macroinvertebrates in the littoral, and crustaceans from the plankton. We also studied if there was a trophic cascade from fish to the littoral epilithic community of these ecosystems. Our results showed that fish presence was linked with the disappearance of most amphibian species and of most conspicuous macroinvertebrates. Minnows also showed sizeable impact on the pelagic habitat reducing the abundance of some herbivorous species of zooplankton that appeared to be unaffected by trout. In the case of amphibian species, we found that, although introduced fish had a high local impact, western-eastern patterns of some environmental variables are the main drivers of amphibian species distribution at Pyrenean range scale. In addition, we confirmed the presence of a littoral trophic cascade that define most of the characteristics of the littoral epilithon of Pyrenean high mountain lakes and ponds, through fish predation of tadpoles and hence, by a drastic reduction of grazing activity.

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34

Ferrer, Maza Dolors. "Effects of parasitism on the condition and reproductive capacity of three commercially exploited fish species in the Mediterranean Sea." Doctoral thesis, Universitat de Girona, 2016. http://hdl.handle.net/10803/385347.

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This PhD thesis evaluates the links between parasitism, condition and reproduction of mature female individuals of three of the most captured fish species in the western Mediterranean Sea: European hake, Merluccius merluccius; red mullet, Mullus barbatus, and European anchovy, Engraulis encrasicolus. Indicators of fish energy reserves (total lipid content in liver, muscle and gonads) and reproductive capacity (fecundity and egg quality) were evaluated, as were the prevalence and intensity of infection by metazoan parasites. By evaluating these relationships, this thesis also provides essential data on the health and reproduction of these three fish species, such as the spawning strategy.
La present tesi doctoral avalua els vincles entre parasitisme, condició i reproducció en femelles adultes de tres de les espècies més capturades a la Mediterrània occidental: el lluç europeu, Merluccius merluccius; el roger de fang, Mullus barbatus, i el seitó, Engraulis encrasicolus. Amb aquesta finalitat, es varen avaluar els indicadors de les reserves energètiques (contingut total de lípids en el fetge, musculatura i gònades) i la capacitat reproductiva (fecunditat i qualitat de la posta), així com la prevalença i intensitat de la infestació per paràsits metazous.Paral·lelament a l’anàlisi d’aquestes relacions, aquesta tesi també proporciona dades essencials sobre la salut i reproducció d’aquestes tres espècies, com per exemple l’estratègia reproductiva.

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35

Costalago, Meruelo David. "Trophic ecology of small pelagic fish in the northwestern Mediterranean / Ecología trófica de peces pelágicos pequeños en el Mediterráneo noroccidental." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/104559.

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In the northwestern Mediterranean anchovy and sardine are among the most ecologically and economically important species. Both species are planktivorous during all their life stages, which could alledgedly lead to expect an overlap of trophic niches. However, trophic interactions between the two species had been, until now, poorly studied. This thesis aims to examine and compare the feeding behaviors of sardine and anchovy at different stages of their development, and during different seasons, in the Gulf of Lions. In this work we have shown, through a detailed analysis of their diets and trophic dynamics, how these two species may interact with each other and with the environment, also considering the possibility of being affected by future climatic changes. We explained that in the sardine, withan almost strictly carnivorous diet at the end of their larval stage and shortly after metamorphosis, the development of their gill rakers and pyloric caeca allow a change in the diet when sardines reach 4 cm standard length (SL), and at 7 cm SL, with these structures already fully developed, they are able to feed on phytoplankton with total effectiveness. Juveniles of both species showed no interspecific trophiv competition, due to their marked differences in their gill rakers and pyloric caeca. We also showed, with the analysis of stable isotopes, that there is dietary change along the development of sardine and anchovy, and that the analysis of stable isotopes (δ13C and δ15N) is essential to identify potential prey, such as appendicularians, whose contribution to the diet is often underestimated when stomach contents are directly analysed. We assessed differences in the nutritional status of anchovy larvae found in summer and in December and estimated their growth rates. The nutritional condition of larvae in December was no different from the condition of larvae with the same size captured in summer. However, the higher daily growth rate of summer larvae suggests that sea temperature significantly influences the development of anchovy larvae. This thesis showed that anchovy and sardine have adapted their abilities and ecological habits in the northwestern Mediterranean to avoid interspecific competition, not just by shuffling their reproductive periods but also adapting their trophic behavior.
En el Mediterráneo noroccidental, anchoa, Engraulis encrasicolus, y sardina, Sardina pilchardus, son las especies más importantes en términos de biomasa y de toneladas capturadas. La anchoa y la sardina son especies planctívoras que consumen, durante todas sus fases de desarrollo, un amplio rango de especies, lo que podría esperarse que se tradujera en un posible solapamiento de sus nichos tróficos. Sin embargo, las interacciones tróficas entre las dos especies habían sido, hasta el momento del inicio de esta tesis, escasamente estudiadas. Esta tesis tiene la finalidad de examinar y comparar, de manera exhaustiva, los comportamientos alimenticios de sardinas y anchoas en diferentes fases de su desarrollo, y durante distintas épocas del año, en el golfo de León, a la vez que pretende mostrar el análisis de algunos de los caracteres morfológicos relacionados con la alimentación de estas especies, como son las branquispinas y los ciegos pilóricos. En este trabajo hemos mostrado, a través de un detallado análisis de sus dietas y de sus dinámicas tróficas, de qué manera estas dos especies pueden interactuar entre ellas y con el medio, considerando especialmente la posibilidad de que se vean afectadas por las perturbaciones derivadas del cambio climático. El primer capítulo expone que en la sardina, con una dieta casi estrictamente carnívora al final de su etapa larvaria y hasta poco después de la metamorfosis, el desarrollo de sus branquispinas y ciegos pilóricos la habilitan para empezar a efectuar un posible cambio de dieta cuando alcanzan los 4 cm de longitud estándar (LE), y que al alcanzar los 7 cm LE ya ha desarrollado por completo dichas estructuras, por lo que es capaz de alimentarse de fitoplancton con total efectividad. En el segundo capítulo se observa que los juveniles de ambas especies no presentan competencia alimenticia interespecífica debido a sus ya marcadas diferencias en el número y disposición de sus branquispinas y en el número de ciegos pilóricos. El tercer capítulo muestra que , por un lado, que existe un cambio de dieta a lo largo del desarrollo de sardina y anchoa y, por otro, que el análisis de isótopos estables (en particular δ13C y δ15N) es esencial para identificar presas potenciales, como por ejemplo las apendicularias, cuya contribución a la dieta cuando se observan directamente los contenidos estomacales suele subestimarse. La aparición en diciembre de larvas de anchoa nos sugirió la idea de realizar un estudio que nos permitiera determinar la influencia del ambiente en el desarrollo y posterior reclutamiento de esta especie. Se evaluaron diferencias en la condición nutricional de ambas cohortes de larvas comparando su composición lipídica y se estimaron sus tasas de crecimiento a partir del análisis de los otolitos. La condición nutricional de las larvas de diciembre no difería de la condición de las larvas de igual tamaño capturadas en verano. Sin embargo, el hecho de que la tasa de crecimiento diario de las larvas de verano sí sea mayor que en diciembre induce a pensar que, ante una probable extensión del periodo de puesta debido a un calentamiento de las aguas superficiales, la temperatura sí influiría de manera significativa en el desarrollo de las larvas de anchoa. Esta tesis demuestra que anchoa y sardina han adaptado sus facultades y hábitos ecológicos en el Mediterráneo noroccidental con el fin de evitar la competencia interespecífica, no sólo alternando sus periodos reproductivos sino también adaptando sus comportamientos tróficos.

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36

Gullberg, Beata. "The Hate U Give and Interpretive Communities : How Young Adult Fiction Can Strengthen a Political Movement." Thesis, Högskolan i Gävle, Avdelningen för humaniora, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-35864.

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In the wake of the guilty verdict of George Floyd’s murderer, police officer Derek Chauvin, there is hope for change in the pattern of police brutality against black people in the United States. The Hate U Give by Angie Thomas was published three years prior to George Floyd’s death, in 2017, and is a realistic fictional novel in the young adult genre that has gained attention for its relevant contribution in the debate of racism and police violence, as the fictional victim Khalil Harris, an unarmed black teenager, does not receive the same justice as George Floyd. In this essay, reader response to The Hate U Give is analysed in order to examine how it affects the opinions and worldview of the reader during and after the read. A close reading and analysis of pivotal scenes was carried out using affective stylistics, in order to interpret what the text does to the reader word-by-word, and subsequently the reader’s creation of meaning was examined and discussed. The reader’s response was then analysed with Stanley Fish’s theoretical framework of interpretive communities, groups with shared social norms and worldviews, which dictate how individuals create meaning in the first place. The analysis suggests that readers of The Hate U Give, while starting out in different, albeit to a certain extent similar, interpretive communities, will gradually align themselves with the interpretive community of Black Lives Matter through shared ideas and opinions and the increased understanding they develop when they read the novel.

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37

Neininger, Sally Louise. "Aspects of dermal bone in genera spanning the fish-tetrapod transition." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619884.

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38

Lanza, Antonio. "Application of multigrid to general relativity." Doctoral thesis, SISSA, 1986. http://hdl.handle.net/20.500.11767/4516.

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Numerical solutions CNakamura, 1981 and reference therein, Piran and Stark, 1984) of Einsteinrs equations following the collapse of axially symmetric rotating bodies show, for some value of the initial ratio a/m, the formation of structure with a toroidal shape around centrally condensed core. If by some mechanisms, the aim ratio of the core is reduced Csee Miller and De Felice, 1985 and De Felice et al., 1985 for a discussion of such mechanisms) to a value less than unity then a rotating black hole may be formed, which will be surrounded by a massive toroidal structure. Other situations in which toroidal structures may be relevant are in the modelling of quasars, active galactic nuclei and other similar objects which most probably contain black holes and thick accretion disks. So far the general relativistic description of these situations had been restricted to the case in which the self-gravity of the disk was negligible CAbramowicz et al., 1978 and Kozlowski et al. 1978) or to the case when both the self-gravity of the disk and the rotation of the black hole could be considered as perturbations CUill, 1974, 19751 to the Schwarzschild black hole. However there may be situations in which the mass of the disk or tori is comparable with that of a rotating hole CUiita, 1985). In this case the full Einstein equations should be solved for the perturbations induced by the self-gravity of the matter to the Kerr black hole. Moreover it is not clear yet whether the self gravity of the disk induces runaway instability. Abramowicz et al. C1980), using a very simple model of the black hole accretion disk system suggested that this kind of instability could act in a few dynamical time scales so that the disk itself could eventually be eaten by the black hole. This instability occurs because the growing black hole changes its gravitational field and therefore the location of the cusp through which matter is accreted changes. On the other hand, Uilson C1984), using models of non-self-gravitating disks in the Kerr metric, concluded that there is no such kind of instability. A final answer to this problem can be given only after sequences of equilibrium configurations of self-gravitating disks or tori around black holes for different masses ratio have been constructed. This means solving numerically Einstein equations consistently with the given distribution of matter. Since the problem is quite complicated in structure and a standard numerical method will not easily cope with it, we have decided to use the Multigrid method CBrandt, 1977) which although is complicated to program will deal naturally with the difficulties of the model. As one of the first applications of the method in general relativity Csee Choptuik and Unruh, 1986, for a different one), we decided to solve few representative test problems before solving the entire one. The plan of the thesis is as follows. In Chapter I we review the general theory of figure of equilibrium in Newtonian and relativistic theories. Chapter II contains a discussion of stationary and axisymmetric space-times and a derivation of Einstein 1 s equations with the relative boundary conditions. Also, included is a discussion and deriv~tion of the equations governing the fluid configuration. Chapter III reviews some numerical techniques used to solve Einstein's equations for stationary and axisymmetric configurations, with particular emphasis to the Multigrid which is the method applied by us. Chapter IV contains an application of Hultigrid in general relativity in the case of vacuum stationary and axisymmetric space-times. In Chapter V we write down the equations for an infinitesimally thin disk around a black hole in Newtonian and relativistic theories. Also, an outline on how to apply the Multigrid in this case, is given. Finally, Chapter VI contains the outline of the application to the case of a self-gravitating toroidal structure around a rapidly rotating black hole.

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39

Giacomazzo, Bruno. "General Relativistic Magnetohydrodynamics: fundamental aspects and applications." Doctoral thesis, SISSA, 2006. http://hdl.handle.net/20.500.11767/4007.

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40

Vitagliano, Vincenzo. "Gravity beyond general relativity : theory and phenomenology." Doctoral thesis, SISSA, 2011. http://hdl.handle.net/20.500.11767/4681.

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Despite the notorious achievements of General Relativity, Einstein's theory is under scrutiny due to the lack of a suitable scheme to quantize gravity as well as for the puzzling features it shows both at strong (early universe, black holes) and weak (Dark Energy problem) regime. The proposal to extend the classical theory of gravity harbours the intriguing goals to cure some of these inconsistencies. A large class of modi cations of General Relativity (GR) has been widely explored in the past; in principle, the main motivation for such early e orts was to solve the problem of non-renormalizability by providing a new framework in which (thanks to higher order corrections in the gravitational action) gravity could be quantized. The analysis of the cosmological implications of such models also showed a number of peculiar features that justi ed further developments. The ultraviolet modi cations that naturally arise at high energy in the context of quantum gravity have been taken into account for their impact on the phenomenology of the very early universe. Furthermore, it was recently argued that alternative infrared extensions of the Einstein-Hilbert (EH) action could be invoked to presumably alleviate the Dark Sector problem.

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41

Sebastiani, Lorenzo. "General Aspects of Modified Theories of Gravity." Doctoral thesis, Università degli studi di Trento, 2011. https://hdl.handle.net/11572/367870.

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The aim of this work is to investigate the both, some mathematical and physical general aspect of modified gravity, and, more specifically, the proprieties of viable, realistic models of modified gravity which can be used to reproduce the inflation and the dark energy epoch of universe today.

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42

Calvó, Perxas Laia. "A study on the phylogeny and the ecology of ammonia-oxidizing bacteria using a new molecular marker based on the gene amoB." Doctoral thesis, Universitat de Girona, 2005. http://hdl.handle.net/10803/7866.

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L'agricultura i la industrialització han causat un augment significatiu del nombre d'ambients rics en amoni. La presència de compostos nitrogenats redueix la qualitat de l'aigua, causant problemes de toxicitat, deteriorant el medi ambient i fins i tot afectant la salut humana. En conseqüència, la nitrificació s'ha convertit en un procés global que afecta al cicle del nitrogen a la biosfera. Els bacteris oxidadors d'amoni (AOB) són els responsables de l'oxidació de l'amoni a nitrit, i juguen un paper essencial en el cicle del nitrogen.
Els primers oxidadors d'amoni foren aïllats a finals del segle XIX, però la lentitud del seu creixement i les dificultats per cultivar-los feren que fins als anys 80, amb els primers estudis emprant el gen 16SrDNA, no s'assolís un coneixement complert d'aquest grup bacterià. Actualment les bases de dades contenen multitud d'entrades amb seqüències corresponents a AOB.
L'objectiu d'aquest treball era trobar, desenvolupar i avaluar eines útils i fiables per a l'estudi dels AOB en mostres ambientals.
En aquest treball primer descrivim la utilització de la hibridació in situ amb fluorescència (FISH), mitjançant l'aplicació de sondes amb diana en el 16SrRNA dels AOB. La FISH ens va permetre detectar i recomptar aquest grup bacterià; no obstant, aquest mètode no permetia la detecció de noves seqüències, pel que es necessitava una nova eina.
Amb aquesta intenció vam aplicar la seqüència de la sonda Nso1225 en una PCR. El fet d'amplificar específicament un fragment del 16SrDNA dels AOB va suposar el desenvolupament d'una nova eina molecular que permetia detectar la presència i diversitat d'aquests bacteris en ambients naturals. Malgrat tot, algunes seqüències pertanyents a bacteris no oxidadors d'amoni del subgrup β dels proteobacteris, eren també obtingudes amb aquesta tècnica. Així mateix, un dels inconvenients de l'ús del 16SrDNA com a marcador és la impossibilitat de detectar simultàniament els AOB que pertanyen als subgrups β i γ dels proteobacteris.
El gen amoA, que codifica per la subunitat A de l'enzim amoni monooxigenasa (AMO), era aleshores àmpliament utilitzat com a marcador per a la detecció dels AOB. En aquest treball també descrivim la utilització d'aquest marcador en mostres procedents d'un reactor SBR. Aquest marcador ens va permetre identificar seqüències de AOB en la mostra, però la necessitat de detectar amoA mitjançant clonatge fa que l'ús d'aquest marcador requereixi massa temps per a la seva utilització com a eina en estudis d'ecologia microbiana amb moltes mostres. Per altra banda, alguns autors han assenyalat l'obtenció de seqüències de no AOB en utilitzar amoA en un protocol de PCR-DGGE.
Amb la finalitat d'obtenir una eina ràpida i rigorosa per detectar i identificar els AOB, vam desenvolupar un joc nou d'oligonucleòtids amb diana en el gen amoB, que codifica per a la subunitat transmembrana de l'enzim AMO. Aquest gen ha demostrat ser un bon marcador molecular pels AOB, oferint, sense tenir en compte afiliacions filogenètiques, una elevada especificitat, sensibilitat i fiabilitat.
En aquest treball també presentem una anàlisi de RT-PCR basada en la detecció del gen amoB per a la quantificació del gènere Nitrosococcus. El nou joc d'oligonucleòtids dissenyat permet una enumeració altament específica i sensible de tots els γ-Nitrosococcus coneguts.
Finalment, vam realitzar un estudi poligènic, comparant i avaluant els marcadors amoA, amoB i 16SrDNA, i vàrem construir un arbre filogenètic combinat.
Com a resultat concloem que amoB és un marcador adequat per a la detecció i identificació dels AOB en mostres ambientals, proporcionant alhora agrupacions consistents en fer inferències filogenètiques. Per altra banda, la seqüència sencera del gen 16S rDNA és indicada com a marcador en estudis amb finalitats taxonòmiques i filogenètiques en treballar amb cultius purs de AOB.
Human activities such as farming and industrialization have produced a significant increase in the number of ammonium-rich environments. The presence of nitrogenated compounds reduces water quality causing toxicity problems, deteriorating the environment and even affecting human health. Consequently, nitrification has recently become a widespread process involving the cycling of nitrogen in the biosphere, which is mainly due to microbial activities. Ammonia oxidizing bacteria (AOB) are an essential component of the global cycling of nitrogen, being responsible for the aerobic oxidation of ammonium to nitrite.
Although the first ammonia oxidizers were isolated by the end of the XIX century, the slowness of their growth and the difficulties in culturing hindered achieving a full knowledge of this bacterial group until the 80s, when the first studies based on the gene 16S rDNA where performed. Nowadays, the databases contain huge numbers of entries of 16SrDNA sequences belonging to AOB.
The aim of this work was to find, develop, and evaluate useful and reliable tools for the study of ammonia oxidizers in environmental samples.
In this work we describe the use of Fluorescence In Situ Hybridization (FISH), based on the use of DNA probes specifically targeting the ammonia-oxidizers 16SrRNA molecule. AOB were detected and enumerated by using this technique. However, unknown sequences are hardly detectable by using this method, and therefore, new tools were needed.
For this purpose we tried applying the sequence of the probe Nso1225 in a PCR reaction. The possibility of specifically amplifying a 16S rDNA gene fragment resulted in a new fingerprinting tool to assess the presence and diversity of ammonia-oxidizers in natural environments. Even so, some β-Proteobacterial non-AOB sequences were also retrieved by using this technique. Moreover, one of the main disadvantages of using 16S rDNA as a molecular marker is the impossibility of simultaneously detecting both the β and the γ-Proteobacterial ammonia oxidizers.
The gene amoA, which encodes for the subunit A of the enzyme ammonia monooxygenase, was then being extensively used as a marker for the detection of AOB in environmental samples. We describe the use of this marker for the identification of several ammonia oxidizing sequences in sludge samples from a sequencing batch reactor (SBR). Although useful, the use of amoA as a marker requires cloning, which is a tedious and time-consuming technique when dealing with large number of samples in microbial ecology studies. Besides, detection of non-AOB sequences has been reported by other authors when using amoA in a PCR-DGGE approach.
Aiming at obtaining a fast and rigorous analytical tool allowing AOB detection and identification, we developed a new set of primers targeting the gene amoB, which encodes for the transmembrane domain of the enzyme ammonia monooxygenase. This gene has been shown to be a good molecular marker for AOB, since it can be used for easy detection and identification of ammonia oxidizers, providing high specificity, sensitivity and reliability regardless of phylogenetic affiliations.
A real-time PCR assay for the detection and quantification of the γ-proteobacterial genus Nitrosococcus based on the amoB gene sequence is also presented. This newly designed primer set allows a highly sensitive and specific enumeration of all known Nitrosococci.
We finally performed a comparison and evaluation of the markers amoA, amoB and 16S rDNA, and built a polygenic based tree.
As a result we conclude that amoB is a suitable molecular tool for detecting and identifying AOB in environmental samples, yielding consistent grouping when performing phylogenetic inferences. In turn, the whole sequence of the gene 16S rDNA is indicated for taxonomical and phylogenetic purposes when working with ammonia oxidizing isolates.

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43

Sebastiani, Lorenzo. "General Aspects of Modified Theories of Gravity." Doctoral thesis, University of Trento, 2011. http://eprints-phd.biblio.unitn.it/672/1/TESI.pdf.

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The aim of this work is to investigate the both, some mathematical and physical general aspect of modified gravity, and, more specifically, the proprieties of viable, realistic models of modified gravity which can be used to reproduce the inflation and the dark energy epoch of universe today.

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44

Ciampa, Alessandra <1971&gt. "Development of methodologies for fish freshness assessment using metabonomics applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5498/1/ciampa_alessandra_tesi.pdf.

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This study focuses on the use of metabonomics applications in measuring fish freshness in various biological species and in evaluating how they are stored. This metabonomic approach is innovative and is based upon molecular profiling through nuclear magnetic resonance (NMR). On one hand, the aim is to ascertain if a type of fish has maintained, within certain limits, its sensory and nutritional characteristics after being caught; and on the second, the research observes the alterations in the product’s composition. The spectroscopic data obtained through experimental nuclear magnetic resonance, 1H-NMR, of the molecular profiles of the fish extracts are compared with those obtained on the same samples through analytical and conventional methods now in practice. These second methods are used to obtain chemical indices of freshness through biochemical and microbial degradation of the proteic nitrogen compounds and not (trimethylamine, N-(CH3)3, nucleotides, amino acids, etc.). At a later time, a principal components analysis (PCA) and a linear discriminant analysis (PLS-DA) are performed through a metabonomic approach to condense the temporal evolution of freshness into a single parameter. In particular, the first principal component (PC1) under both storage conditions (4 °C and 0 °C) represents the component together with the molecular composition of the samples (through 1H-NMR spectrum) evolving during storage with a very high variance. The results of this study give scientific evidence supporting the objective elements evaluating the freshness of fish products showing those which can be labeled “fresh fish.”
Il presente studio è centrato all’utilizzo di applicazioni metabonomiche, finalizzate alla misura della freschezza di prodotti ittici in funzione della specie biologica e della modalità di conservazione. Questo approccio metabonomico nello studio in esame è innovativo e si basa sulla profilazione molecolare mediante la risonanza magnetica nucleare (NMR), per valutare da una parte se una tipologia di pesce ha ancora mantenuto, entro certi limiti, le proprie caratteristiche sensoriali e nutrizionali presenti al tempo iniziale e dall’altra per osservare le eventuali alterazioni che intervengono nella composizione del prodotto ittico. I dati spettroscopici sperimentali ottenuti attraverso la risonanza magnetica nucleare, 1H-NMR, dei profili molecolari di estratti di pesce preparati in modo opportuno sono stati confrontati con quelli ottenuti sugli stessi campioni attraverso metodiche analitiche strumentali classiche e convenzionali, a cui le metodologie ufficiali fanno riferimento. Quest’ultime vengono utilizzate per l’ottenimento di indici chimici di freschezza derivanti dalla degradazione biochimica e microbica di composti azotati proteici e non (trimetilammina ,N-(CH3)3, nucleotidi, amminoacidi, ecc.). In un secondo momento mediante un approccio metabonomico è stata eseguita un’analisi delle componenti principali (PCA) e un’analisi discriminante lineare (PLS-DA) al fine di condensare il concetto di evoluzione temporale della freschezza in un parametro omnicomprensivo. In particolare, la prima componente principale (PC1) in entrambe le condizioni di conservazione (4 °C e 0 °C) rappresenta la componente lungo la quale la composizione molecolare dei campioni, descritta dallo spettro1H-NMR, evolve durante il tempo di conservazione con una varianza molto elevata. I risultati di questo studio vogliono mirare ad ottenere un supporto scientifico che sia in grado di fornire elementi oggettivi di valutazione, per far si che il prodotto ittico possa fregiarsi della denominazione di “pesce fresco”.

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45

Ciampa, Alessandra <1971&gt. "Development of methodologies for fish freshness assessment using metabonomics applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5498/.

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Анотація:

This study focuses on the use of metabonomics applications in measuring fish freshness in various biological species and in evaluating how they are stored. This metabonomic approach is innovative and is based upon molecular profiling through nuclear magnetic resonance (NMR). On one hand, the aim is to ascertain if a type of fish has maintained, within certain limits, its sensory and nutritional characteristics after being caught; and on the second, the research observes the alterations in the product’s composition. The spectroscopic data obtained through experimental nuclear magnetic resonance, 1H-NMR, of the molecular profiles of the fish extracts are compared with those obtained on the same samples through analytical and conventional methods now in practice. These second methods are used to obtain chemical indices of freshness through biochemical and microbial degradation of the proteic nitrogen compounds and not (trimethylamine, N-(CH3)3, nucleotides, amino acids, etc.). At a later time, a principal components analysis (PCA) and a linear discriminant analysis (PLS-DA) are performed through a metabonomic approach to condense the temporal evolution of freshness into a single parameter. In particular, the first principal component (PC1) under both storage conditions (4 °C and 0 °C) represents the component together with the molecular composition of the samples (through 1H-NMR spectrum) evolving during storage with a very high variance. The results of this study give scientific evidence supporting the objective elements evaluating the freshness of fish products showing those which can be labeled “fresh fish.”
Il presente studio è centrato all’utilizzo di applicazioni metabonomiche, finalizzate alla misura della freschezza di prodotti ittici in funzione della specie biologica e della modalità di conservazione. Questo approccio metabonomico nello studio in esame è innovativo e si basa sulla profilazione molecolare mediante la risonanza magnetica nucleare (NMR), per valutare da una parte se una tipologia di pesce ha ancora mantenuto, entro certi limiti, le proprie caratteristiche sensoriali e nutrizionali presenti al tempo iniziale e dall’altra per osservare le eventuali alterazioni che intervengono nella composizione del prodotto ittico. I dati spettroscopici sperimentali ottenuti attraverso la risonanza magnetica nucleare, 1H-NMR, dei profili molecolari di estratti di pesce preparati in modo opportuno sono stati confrontati con quelli ottenuti sugli stessi campioni attraverso metodiche analitiche strumentali classiche e convenzionali, a cui le metodologie ufficiali fanno riferimento. Quest’ultime vengono utilizzate per l’ottenimento di indici chimici di freschezza derivanti dalla degradazione biochimica e microbica di composti azotati proteici e non (trimetilammina ,N-(CH3)3, nucleotidi, amminoacidi, ecc.). In un secondo momento mediante un approccio metabonomico è stata eseguita un’analisi delle componenti principali (PCA) e un’analisi discriminante lineare (PLS-DA) al fine di condensare il concetto di evoluzione temporale della freschezza in un parametro omnicomprensivo. In particolare, la prima componente principale (PC1) in entrambe le condizioni di conservazione (4 °C e 0 °C) rappresenta la componente lungo la quale la composizione molecolare dei campioni, descritta dallo spettro1H-NMR, evolve durante il tempo di conservazione con una varianza molto elevata. I risultati di questo studio vogliono mirare ad ottenere un supporto scientifico che sia in grado di fornire elementi oggettivi di valutazione, per far si che il prodotto ittico possa fregiarsi della denominazione di “pesce fresco”.

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46

Rezzolla, Luciano. "General relativistic hydrodynamics of compressible multicomponent fluids: developments and applications." Doctoral thesis, SISSA, 1997. http://hdl.handle.net/20.500.11767/3985.

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47

Kawamura, Takumu. "General relativistic magnetohydrodynamic simulations of binary neutron star mergers." Doctoral thesis, University of Trento, 2017. http://eprints-phd.biblio.unitn.it/1922/1/Takumu_Kawamura_thesis_archiving.pdf.

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In this thesis I present results of my fully general relativistic magnetohydrodynamic (GRMHD) binary neutron star merger (BNS) simulations, conducted by using the numerical code "Whisky" under various conditions, such as, different Equation of State (EOS) for neutron matter (APR4, Ideal fluid and H4 EOSs), masses (with equal/unequal masses for two neutron stars), different magnetic field configurations (both fields of two neutron stars aligned with the inspiral axis, one aligned and one anti-aligned, and both anti-aligned) to investigate the effect of these parameters on the dynamics of the simulations and possibility of forming relativistic jets, which is thought to be one of the necessary conditions for the central engine of short gamma-ray bursts (SGRBs).

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48

Andorrà, Solsona Immaculada. "Adaptation and development of culture-independent techniques for the indentification and enumeration of microorganisms in wine fermentations." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/8690.

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L'objectiu d'aquesta tesi va ser l'adaptació i validació de diferents tècniques independents de cultiu per a la detecció i quantificació de la microbiota present a la fermentació vínica. Es van assajar la QPCR (PCR quantitativa) per a la quantificació i seguiment d'espècies clau i la diversitat ecològica es va analitzar per DGGE (electroforesi en gel desnaturalitzant) i la clonació d'un fragment ribosomal.
Tanmateix es va estudiar l'aplicació de la Hibridació in Situ (FISH) i la QPCR amb colorants específics per tal de diferenciar cèl·lules vives i mortes.
Aquestes tècniques es varen aplicar a fermentacions industrials, essent notable la detecció de bacteris acètics i llevats No-Saccharomyces en concentracions superiors a les detectades com a poblacions cultivables. Es van estudiar interaccions entre llevats Saccharomyces i No-Saccharomyces al laboratori, observant-ne la supervivència d'aquestes en estats viables però no cultivables.
Aquestes tècniques independents de cultiu indiquen una població i dinàmiques microbianes prèviament desapercebudes.
The objective of this thesis was the adaptation and validation of different culture-independent techniques for detection and quantification of the microbiota present in wine fermentation. We tested the QPCR (PCR quantitative) for the quantification and monitoring of key species. The ecological diversity was analyzed by DGGE (denaturing gradient gel electrophoresis) and by cloning of a ribosomal fragment.
However, we studied the application of in Situ Hybridization (FISH) and QPCR with specific dyes to differentiate between live and dead cells.
These techniques were applied in industrial fermentations, being significant the detection of acetic acid bacteria and Non-Saccharomyces yeast in concentrations higher than those identified as culturable populations. We studied the interactions between Saccharomyces and Non-Saccharomyces yeast in the laboratory, observing their survival in these viable but non-culturable state.
These culture-independent techniques indicate a population and microbial dynamics previously unnoticed.

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49

Knudsen, Richard Ray. "A Study on the Integration of Multivariate MetOcean, Ocean Circulation, and Trajectory Modeling Data with Static Geographic Information Systems for Better Marine Resources Management and Protection During Coastal Oil Spill Response – A Case Study and Gap Analysis on Northeastern Gulf of Mexico Tidal Inlets." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5974.

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The Oil Pollution Act of 1990 requires the development of Regional and Area Contingency Plans. For more than 20 years, the State of Florida, under both the Department of Environmental Protection and the Florida Fish and Wildlife Commission, has worked closely with the U.S. Coast Guard and the National Oceanic and Atmospheric Administration to develop these plans for coastal and marine oil spill response. Current plans, developed with local, state and federal stakeholder input, use geographic information systems (GIS) data such as location and extent of sensitive ecological, wildlife, and human-use features (termed Environmental Sensitivity Index data), pre-defined protection priorities, and spatially explicit protection strategies to support decision-making by responders (termed Geographic Response Plans). However, they are long overdue for improvements that incorporate modern oceanographic modeling techniques and integrated data from coastal ocean observing systems. Better understanding of circulation in nearshore and estuarine waters, at a scale consistent with other spatial data, is especially lacking in Area Contingency Plans. This paper identifies the gaps in readily available information on the circulation-driven causes and effects missing in current oil spill contingency planning and describes a sample methodology whereby multiple coastal and ocean spatial science disciplines are used to answer questions that no single, non-integrated discipline can answer by itself. A path forward for further integration and development of more comprehensive plans to better support coastal protection in Florida is proposed. The advances made here are applicable to other coastal regions of the world.

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50

Vernieri, Daniele. "Gravity beyond General Relativity: New Proposals and their Phenomenology." Doctoral thesis, SISSA, 2014. http://hdl.handle.net/20.500.11767/3860.

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This Thesis is devoted to the study of phenomenologically viable gravitational theories, in order to address the most pressing open issues both at very small and very large energy scales. Lovelock’s theorem singles out General Relativity as the only theory with secondorder field equations for the metric tensor. So, two possible ways to circumvent it and modify the gravitational sector are taken into account. The first route consists in giving up diffeomorphism invariance, which generically leads to extra propagating degrees of freedom. In this framework Horava gravity is discussed, presenting two restrictions, called respectively "projectability" and "detailed balance", which are imposed in order to reduce the number of terms in the full theory. We introduce a new version of the theory assuming detailed balance but not projectability, and we show that such theory is dynamically consistent as both the spin-0 and spin-2 gravitons have a well behaved dynamics at low-energy. Moreover three-dimensional rotating black hole solutions are found and fully studied in the context of Horava gravity, shedding light on its causal structure. A new concept of black hole horizon, dubbed "universal horizon", arises besides the usual event horizon one, since in Lorentz-violating gravity theories there can be modes propagating even at infinite speed. The second route which is considered, consists in adding extra fields to the gravitational action while diffeomorphism invariance is preserved. In this respect we consider the less explored option that such fields are auxiliary fields, so they do not satisfy dynamical equations but can be instead algebraically eliminated. A very general parametrization for these theories is constructed, rendering also possible to put on them very tight, theory-independent constraints. Some insight about the cosmological implications of such theories is also given. Finally in the conclusions we discuss about the future challenges that the aforementioned gravity theories have to face.

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