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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Sex Chromosome Evolution in Blow Flies

Anne Amarila Andere (9120365) 28 July 2020 (has links)
<div>Chromosomal mechanisms of sex determination vary greatly in phylogenetically closely related species, indicative of rapid evolutionary rates. Sex chromosome karyotypes are generally conserved within families; however, many species have derived sex chromosome configurations. Insects display a plethora of sex chromosome systems due to rapid diversification caused by changes in evolutionary processes within and between species. A good example of such a system are insects in the blow fly family Calliphoridae. While cytogenetic studies observe that the karyotype in blow flies is highly conserved (five pairs of autosomal chromosomes and one pair sex chromosome), there is variation in sex determining mechanisms and sex chromosome structure within closely related species in blow flies. The evolutionary history of sex chromosomes in blow fly species have not been fully explored. Therefore, the objective of this research was to characterize the sex chromosome structures in four species of blow flies and investigate the selective forces which have played a role in shaping the diverse sex chromosome system observed in blow flies. The blow fly species used in this study are Phormia regina, Lucilia cuprina, Chrysomya rufifacies and Chrysomya albiceps. Phormia regina,and Lucilia cuprina have a heteromorphic sex chromosome system and are amphogenic (females produce both male and female offspring in equal ratio). In contrast, Chrysomya rufifacies and Chrysomya albiceps, have a homomorphic sex chromosome system, are monogenic (females produce unisexual progeny), have two types of females (arrhenogenic females – male producers and thelygenic females – female producers), and sex of the offspring is determined by the maternal genotype. </div><div>To accomplish these tasks, a total of nine male and female individual draft genomes for each of the four species (including three individual draft genomes of Chrysomya rufifacies – male, and the two females) were sequenced and assembled providing genomic data to explore sex chromosome evolution in blow flies. Whole genome analysis was utilized to characterize and identify putative sex chromosomal sequences of the four blow fly species. Genomic evidence confirmed the presence of genetically differentiated sex chromosomes in P. regina and L. cuprina; and genetically undifferentiated sex chromosomes in C. rufifacies and C. albiceps. Furthermore, comparative analysis of the ancestral Dipteran sex chromosome (Muller element F in Drosophila) was determined to be X-linked in P. regina and L. cuprina contributing to sex chromosome differentiation but not sex-linked in C. rufifacies and C. albiceps. Evolutionary pressures are often quantified by the ratio of substitution rates at non-synonymous (dN) and synonymous (dS) sites. Substitution rate ratio analysis (dN/dS) of homologous genes indicated a weaker purifying selection may have contributed to the loss of sex-linked genes in Muller element F genes of the undifferentiated sex chromosome as compared to the differentiated sex chromosome system. Overall, the results presented herein greatly expands our knowledge in sex chromosome evolution within blow flies and will reinforce the study of sex chromosome evolution in other species with diverse sex chromosome systems.</div><div><br></div>
152

Mateřská škola / Kindergarten

Vejr, Tomáš Unknown Date (has links)
The thesis solves the project of a kindergarten in the field of inclination 7%. The kindergarten is located on the plots number 570, st. 373, st. 374 in the village Vrané nad Vltavou. The building has two floors and one basement. The kindergarten is for 60 children and for 11 employees. The building serves as a preschool institution for raising children. The supporting structure consists of a precast concrete frame supplemented in the basement by a cast-in-place wall and a foundation slap. External walls and partitions form sand-lime bricks Sendwich. The external walls are completed with Orsilt TF Profi mineral insulation th. 280 mm. The floors are made of prestressed concrete floor slabs Spiroll PPD 256 th. 250 mm supported by T and L primary beams. The building ends with a could extensive green roof. The slope and space for the blow-in insulation Climatizer Plus uses Steico Joist 400 I-beams. Windows are wooden frame Optiwin Purista and doors are Optiwin Entrada.
153

Équations aux dérivées partielles de type Keller-Segel en dynamique des populations et de type Fokker-Planck en neurosciences / Partial differential equations of Keller-Segel type in population dynamics and of Fokker-Planck type in neurosciences

Roux, Pierre 06 December 2019 (has links)
Dans cette thèse, j'étudie des équations aux dérivées partielles qui modélisent des phénomènes biologiques.Dans la première partie, je m'intéresse à une variante des équations de Keller-Segel qui modélise la chimiotaxie des micro-organismes et vise à expliquer la façon dont des colonies bactériennes s'auto-organisent et forment, en fonction de la quantité de nutriments disponibles, différents motifs géométriques. Pour le modèle en question, je construis des solutions et j'étudie leur comportement en temps long. Je montre que certaines solutions explosent en temps fini.Dans la deuxième partie, je m'intéresse au modèle Intègre et tire avec bruit et fuite non-linéaire, une équation de type Fokker-Planck qui décrit l'activité d'un réseau de neurones. J'améliore certaines estimées sur l'existence globale et l'explosion en temps fini et je démontre des résultats pour une variante du modèle avec un délai synaptique : existence globale, comportement en temps long, recherche de solutions périodiques.Dans la troisième partie, je propose une modélisation d'abord stochastique, ensuite déterministe, pour le phénomène d'adaptation des dommages à l'ADN chez les eucaryote. Des simulations numériques sont proposées et commentées. / In this thesis, I study some partial differential equations modelling biological phenomena.In the first part, I am concerned with a variant of the Keller-Segel equations which models chemotaxis in microorganisms and aims at understanding the way they self-organise and form, depending upon the density of nutrients, different geometrical patterns. For this model, I construct solutions and I study their long time behaviour. I show that some solutions blow-up in finite time.In the second part, I study the model Nonlinear Noisy leaky integrate and fire, a Fokker-Planck type equation which describes the activity of a neural network. I upgrade some estimates on global existence and finite time blow-up and I prove results for a variant of the model in which a synaptic delay is added : global existence, long time behaviour, search of periodic solutions.In the third part, I propose a stochastic model, and then a deterministic model, for the phenomenon of adaptation to DNA damage in eukaryotes. Numerical simulations are proposed and discussed.
154

Mateřská škola / Kindergarten

Vejr, Tomáš January 2021 (has links)
The thesis solves the project of a kindergarten in the field of inclination 7%. The kindergarten is located on the plots number 570, st. 373, st. 374 in the village Vrané nad Vltavou. The building has two floors and one basement. The kindergarten is for 60 children and for 11 employees. The building serves as a preschool institution for raising children. The supporting structure consists of a precast concrete frame supplemented in the basement by a cast-in-place wall and a foundation slap. External walls and partitions form sand-lime bricks Sendwich. The external walls are completed with Orsilt TF Profi mineral insulation th. 280 mm. The floors are made of prestressed concrete floor slabs Spiroll PPD 256 th. 250 mm supported by T and L primary beams. The building ends with a could extensive green roof. The slope and space for the blow-in insulation Climatizer Plus uses Steico Joist 400 I-beams. Windows are wooden frame Optiwin Purista and doors are Optiwin Entrada.
155

My Body In Visual Culture

Ritter, Amy B. 25 September 2014 (has links)
No description available.
156

Water blow out phenomena inside a heavy truck silencer / Vatten blåser ut fenomen i en tung ljuddämpare

Suram Venkata Subramaniyam, Rohit January 2020 (has links)
NOx sensors have become salient components in the development of efficient exhaust after treatment system for heavy duty vehicles in the past few years. When the accumulated water inside the silencer splashes on to the NOx sensor, it can cause permanent cracks in the sensor. To protect the sensor from this mode of failure, a dew point strategy is developed at Scania. This is important to predict when it is safe to switch on the NOx sensor without causing any harm to it. But the strategy currently includes only the phase transfer phenomena and neglects the effect of the water blow out phenomena inside the silencer. To investigate the effect of water blow out, an experimental test method is designed and the experiments are conducted at different locations in the silencer. The results from the experiments shows that the effect of water blow out is certainly an important factor to develop a better dew point strategy model. For a selected location, the quantity of water remaining after blow out and the time taken for the blow out phase are collected as data from the experiments. A mathematical model for the water blow out phenomena is developed in MATLAB. The model estimates the maximum amount of water which could be present in all the subvolumes of the silencer considering the effect of water blow out. The model is verified with the experimental data for a Scania CAS1 silencer. Calibration guidelines for the developed blow out model are also documented in this report. / NOx sensorer har blivit viktiga komponenter i utvecklingen av ett effektivt avgassystem för tunga fordon under de senaste åren. När det ackumulerade vattnet i ljuddämparen stänker på NOx-sensorn kan det orsaka permanenta sprickor i sensorn. För att skydda sensorn från detta misslyckande utvecklas en daggpunktsstrategi på Scania. Detta är viktigt att förutsäga när det är säkert att slå på NOx-sensorn utan att skada den. Men strategin innehåller för närvarande endast fasöverföringsfenomenen och försummar effekten av att vatten blåser ut fenomen inuti ljuddämparen. För att undersöka effekten av utblåsning av vatten utformas en experimentell testmetod och experimenten utförs på olika platser i ljuddämparen. Resultaten från experimenten visar att effekten av vattenblåsning verkligen är en viktig faktor för att utveckla en bättre daggpunktsstrategimodell. För en vald plats samlas mängden vatten kvar efter utblåsning och den tid det tar för utblåsningsfasen som data från experimenten. En matematisk modell för fenomen för vattenblåsning utvecklas i MATLAB. Modellen uppskattar den maximala mängden vatten som kan finnas i ljuddämparens undervolymer med tanke på effekten av vatten som blåser ut. Modellen verifieras med experimentdata för en Scania CAS1 ljuddämpare. Kalibreringsriktlinjer för den utvecklade utblåsningsmodellen dokumenteras också i denna rapport.
157

Fully linear elliptic equations and semilinear fractionnal elliptic equations

Chen, Huyuan 10 January 2014 (has links)
Cette thèse est divisée en six parties. La première partie est consacrée à l'étude de propriétés de Hadamard et à l'obtention de théorèmes de Liouville pour des solutions de viscosité d'équations aux dérivées partielles elliptiques complètement non-linéaires avec des termes de gradient, ... / This thesis is divided into six parts. The first part is devoted to prove Hadamard properties and Liouville type theorems for viscosity solutions of fully nonlinear elliptic partial differential equations with gradient term ...
158

Prestige and prurience : the decline of the American art house and the emergence of sexploitation, 1957-1972

Metz, Daniel Curran 01 November 2010 (has links)
“Prestige and Prurience: The Decline of the American Art House and the Emergence of Sexploitation, 1957-1972” presents a historical narrative of the art house theatre during the 1960s and its surrounding years, examining the ways in which art theatres transformed into adult theatres during the 1960s and 1970s. Beginning in earnest in the immediate post-war period, art houses in America experienced a short period of growth before stagnating in the middle 1950s. With the release in 1957 of the erotically charged Brigitte Bardot film …And God Created Woman, a new era of art houses followed, one that is characterized by the emergence of sexualized advertising, content and stars. As the 1960s came, sex films like The Immoral Mr. Teas played on art film marketing strategies and even screened in many art houses. Gradually, sexploitation films began to dominate art house programs and replace European art films and Hollywood revivals. In this transitional period, however, sexploitation films used key strategies to emulate many art film characteristics, and likewise art films used sexploitation techniques in order to maintain marketability for American distribution and exhibition. By studying the promotion and programming used by art house theatres during this period, this thesis identifies and announces a number of key trends within the dynamic period for art houses. The period is distinguished by its convergence of practices related to prestigious and prurient signs, merging art and sex in ways unique to the era and to the circumstances by which sex films infiltrated art houses and art films pandered to salacious interests. It presents a new perspective on the history of art houses, art cinema, American exhibition, sexploitation films, hardcore pornography and censorship. / text
159

Sur certains systèmes hamiltoniens liés à l’équation de Szegő cubique / On certain Hamiltonian systems related to the cubic Szegő equation

Xu, Haiyan 14 September 2015 (has links)
Cette thèse est principalement consacrée à l’étude du comportement en temps long de solutions de certaines équations aux dérivées partielles hamiltoniennes, du type i∂_t u=X_H (u), en particulier l’existence globale, la croissance des normes de Sobolev, la diffusion et l’approximation par la dynamique résonante.Dans ce contexte, nous considérons d’abord une perturbation de l’équation de Szegő cubique par un potentiel linéaire, i∂_t u=∏ |u|² u+α∫ u,α∈R, (α-Szegő) où ∏▒ désigne le projecteur de Szegő sur les fréquences positives. Pour α=0, cette équation est l’équation de Szegő cubique, étudiée récemment par Gérard et Grellier comme modèle mathématique d’équation non linéaire et non dispersive. Pour l’équation (α–Szegő), nous établissons le caractère bien posé et la complète intégrabilité, et étudions la dynamique des valeurs singulières des opérateurs de Hankel associés. En outre, nous montrons les propriétés suivantes pour cette équation, sur une classe de sous–variétés invariantes de dimensions finies arbitrairement grandes : si α<0, toute trajectoire est relativement compacte, et toute norme de Sobolev est bornée le long de cette trajectoire. Siα>0, il existe des trajectoires le long desquelles toutes les normes de Sobolev de régularité plus grande que ½ tendent exponentiellement vers l’infini en temps.Dans une seconde partie, nous étudions un système mixte Schrödinger–ondes sur le cylinder (x,y)∈R×T , i∂_t U+∂_xx U-|D_y |U=|U|² U,(WS)En adaptant une idée de Hani–Pausader–Tzvetkov–Visciglia, nous établissons une théorie du scattering modifiée reliant les petites solutions de cette équation et les petites solutions de l’équation de Szegő cubique. En combinant cette théorie du scattering avec un résultat récent de Gérard–Grellier, nous en déduisons l’existence de solutions globales de (WS) qui sont non bornées dans l’espace L_x² H_y^s (R×T) pour tout s>½ . / The main purpose of this Ph.D. thesis is to study the long time behavior of solutionsto some Hamiltonian PDEs, i∂_t u=X_H (u), including global existence, growth of high Sobolev norms, scattering and long time approximation by resonant dynamics.In this context, at first we consider the Szegő equation on the circle S1 perturbed bya linear potential, i∂_t u=∏ |u|² u+α∫ u,α∈R, (α-Szegő) where ∏ is the projector onto the non-negative frequencies. For α=0, it turns out tobe the cubic Szegő equation, which was recently introduced by Gérard and Grellier as amathematical toy model of a non-linear totally non dispersive equation.We study the global well-posedness, the integrability and the dynamics of the singularvalues of the related Hankel operators of the α –Szegő equation. Moreover, we establishthe following properties for this equation on a class of invariant submanifolds, with anarbitrary large dimension. For α<0, any trajectory is relatively compact, and all theSobolev norms are bounded on it. For α>0, there exist trajectories on which everySobolev norm of regularity s>½ , exponentially tends to infinity in time.Second, we study the wave-guide Schrödinger equation posed on the spatial domain(x,y)∈R×T ,i∂_t U+∂_xx U-|D_y |U=|U|² U,(WS)Adapting an idea by Hani–Pausader–Tzvetkov–Visciglia, we establish a modified scattering theory between small solutions to this equation and small solutions to the cubic Szegő equation. Combining this scattering theory with a recent result by Gérard–Grellier, we infer existence of global solutions to (WS) which are unbounded in the space L_x^2 H_y^s (R×T) for every s>½ .
160

Contributions aux équations d'évolution frac-différentielles / Contributions to frac-differential evolution equations

Lassoued, Rafika 08 January 2016 (has links)
Dans cette thèse, nous nous sommes intéressés aux équations différentielles fractionnaires. Nous avons commencé par l'étude d'une équation différentielle fractionnaire en temps. Ensuite, nous avons étudié trois systèmes fractionnaires non linéaires ; le premier avec un Laplacien fractionnaire et les autres avec une dérivée fractionnaire en temps définie au sens de Caputo. Dans le premier chapitre, nous avons établi les propriétés qualitatives de la solution d'une équation différentielle fractionnaire en temps qui modélise l'évolution d'une certaine espèce. Plus précisément, l'existence et l'unicité de la solution globale sont démontrées pour certaines valeurs de la condition initiale. Dans ce cas, nous avons obtenu le comportement asymptotique de la solution en t^α. Sous une autre condition sur la donnée initiale, la solution explose en temps fini. Le profil de la solution et l'estimation du temps d'explosion sont établis et une confirmation numérique de ces résultats est présentée. Les chapitres 4, 5 et 6 sont consacrés à l'étude théorique de trois systèmes fractionnaires : un système de la diffusion anormale qui décrit la propagation d'une épidémie infectieuse de type SIR dans une population confinée, le Brusselator avec une dérivée fractionnaire en temps et un système fractionnaire en temps avec une loi de balance. Pour chaque système, on présente l'existence globale et le comportement asymptotique des solutions. L'existence et l'unicité de la solution locale pour les trois systèmes sont obtenues par le théorème de point fixe de Banach. Cependant, le comportement asymptotique est établi par des techniques différentes : le comportement asymptotique de la solution du premier système est démontré en se basant sur les estimations du semi-groupe et le théorème d'injection de Sobolev. Concernant le Brusselator fractionnaire, la technique utilisée s'appuie sur un argument de feedback. Finalement, un résultat de régularité maximale est utilisé pour l'étude du dernier système. / In this thesis, we are interested in fractional differential equations. We begin by studying a time fractional differential equation. Then we study three fractional nonlinear systems ; the first system contains a fractional Laplacian, while the others contain a time fractional derivative in the sense of Caputo. In the second chapter, we establish the qualitative properties of the solution of a time fractional equation which describes the evolution of certain species. The existence and uniqueness of the global solution are proved for certain values of the initial condition. In this case, the asymptotic behavior of the solution is dominated by t^α. Under another condition, the solution blows-up in a finite time. The solution profile and the blow-up time estimate are established and a numerical confirmation of these results is presented. The chapters 4, 5 and 6 are dedicated to the study of three fractional systems : an anomalous diffusion system which describes the propagation of an infectious disease in a confined population with a SIR type, the time fractional Brusselator and a time fractional reaction-diffusion system with a balance law. The study includes the global existence and the asymptotic behavior. The existence and uniqueness of the local solution for the three systems are obtained by the Banach fixed point theorem. However, the asymptotic behavior is investigated by different techniques. For the first system our results are proved using semi-group estimates and the Sobolev embedding theorem. Concerned the time fractional Brusselator, the used technique is based on an argument of feedback. Finally, a maximal regularity result is used for the last system.

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