Chez les eucaryotes pluricellulaires, la différenciation des cellules repose en partie sur l’activation oula répression des gènes. Les profils d’expression génique mis en place vont perdurer d’une générationcellulaire à l’autre. Ce phénomène met en jeu des mécanismes épigénétiques qui remodèlentlocalement la structure de la chromatine. Chez Drosophila melanogaster, les protéines des groupesPolycomb (PcG) et Trithorax (TrxG) participent au maintien du profil d’expression des gènes au coursdu développement. Les protéines PcG maintiennent les gènes réprimés tandis que les protéines TrxGmaintiennent les gènes activés. Une troisième classe de protéines nommée Enhancers of Trithoraxand Polycomb (ETP) module l’activité des PcG et TrxG. Dorsal Switch Protein 1 (DSP1) est uneprotéine HMGB (High Mobility Group B) classée comme une ETP. Par tamisage moléculaire, nousavions montré que la protéine DSP1 était présente au sein de complexes de poids moléculaire de 100kDa à 1 MDa. Le travail de thèse présenté ici a pour but d’identifier les partenaires de la protéineDSP1 dans l’embryon et de mieux connaître les propriétés biochimiques de DSP1. Premièrement, j’aimis en place puis effectué l’immunopurification des complexes contenant DSP1 dans des extraitsprotéiques embryonnaires. Cette approche nous a permis d’identifier 23 partenaires putatifs de laprotéine DSP1. Parmi ces protéines, nous avons identifié la protéine Rm62 qui est une ARN hélicaseà boîte DEAD. Les relations biologiques entre DSP1 et Rm62 ont été précisées. Deuxièmement, j’aidéterminé, par une approche biochimique, de nouvelles caractéristiques physico-chimiques de laprotéine DSP1. / In multicellular organism, the identity of cell is determined by several factors playing on genesexpression. Once established, the gene expression pattern is transmitted to daughter cells through aprocess involving epigenetic mechanisms that locally reshape the structure of chromatin. In Drosophilamelanogaster, the Polycomb (PcG) and trithorax (trxG) group genes are involved in the maintenanceof gene expression profile during development. Inside multimeric complexes, PcG proteins maintaingenes in repressed state whereas TrxG maintain genes active. A third class of proteins, calledEnhancers of Trithorax and Polycomb, regulate PcG and TrxG activities. Dorsal Switch Protein 1(DSP1) is a High Mobility Group B protein acting as an ETP. But DSP1 has not yet been identified inPcG or TrxG complexes. On the basis of gel filtration analysis of protein complexes in embryo nuclearextracts, it appears that the majority of DSP1 is present in complex(es) from 100 kDa to 1MDa. Aimsof present work are the identification of DSP1 protein partners in drosophila embryo and thecharacterization of biochemical properties of DSP1. Firstly, I used immunopurification from drosophilaembryonic nuclear extracts. The proteins purified with DSP1 were characterized through sequencingof peptides from individual protein bands by mass spectrometry. Among identified proteins, wefocused on the DEAD Box RNA helicase, Rm62. The role of interaction between DSP1 and Rm62 hasbeen characterized. Secondly, I have identified a new physicochemical aspect of DSP1 protein.

La Résonance Quadrupolaire Nucléaire (RQN) est une technique spectroscopique appliquée à l’état solide et qui ne nécessite aucun champ magnétique statique contrairement à la Résonance Magnétique Nucléaire (RMN). Elle permet de détecter, les molécules qui contiennent un noyau quadrupolaire (tel que l'azote-14). La RQN de l’azote-14 suscite un intérêt particulier car elle s'avère utile dans la détection de drogues et d’explosifs, qui contiennent, pour la plupart, des molécules azotées. Cette thèse porte en premier lieu sur l’amélioration de la qualité spectrale en résonance quadrupolaire (RQN) de l’azote-14. Ainsi, nous nous sommes préoccupés des signaux transitoires (ringing) qui suivent l’impulsion radiofréquence (rf) et qui masquent en partie le signal RQN. Nous avons d’abord montré, par une étude théorique et expérimentale, que les mesures à basse puissance (< 3Watts) étaient possibles, ce qui nous a permis de diminuer l’amplitude du ringing. De plus, grâce à ce mode de fonctionnement (basse puissance), nous avons pu proposer un circuit original de commutation du facteur de qualité (Q-switch) basé sur un commutateur rf CMOS et qui a permis de diminuer la durée du ringing. La seconde partie traite de l’influence d’un champ magnétique statique faible amplitude et des divers paramètres expérimentaux en RQN de l’azote-14. Dans le cas où le tenseur de gradient de champ électrique est de symétrie axiale, nous avons observé des élargissements, voire des doublets Zeeman. En revanche, dans le cas général (absence de symetrie), nous avons mis en évidence la possibilité définir le tenseur de gradient de champ électrique à partir de la forme de raie d’une seule transition au lieu de deux transitions (sans champ magnétique statique). Ce dernier résultat pourrait permettre de diminuer de moitié le temps nécessaire à la caractérisation d’une nouvelle molécule azotée. / Nuclear quadrupole resonance (NQR) is a solid-state spectroscopic technique which doesn't require a static magnetic field in contrast to Nuclear Magnetic Resonance (NMR). It is used to detect molecules containing quadrupole nuclei (such as nitrogen-14). Nitrogen-14 quadrupole resonance is of particular interest because it is useful in the detection of drugs and explosives, which contain mostly of nitrogen molecules. In this thesis we have primarily focused on improving the spectral quality in nitrogen-14 quadrupole resonance (NQR) . Thus, we were concerned with the transient signals ( ringing ) following the radiofrequency (rf) pulse and which partly overwhelm the NQR signal. First, we demonstrated by theoretical and experimental study that low power measurements (< 3Watts ) were possible, allowing us to reduce the ringing amplitude. In addition, through this mode ( low power ), we have proposed an original quality factor switching circuit (Q -switch ) based on rf CMOS switch and which has reduced the ringing duration. The second part deals with the effect of a weak static magnetic field and various experimental parameters in nitrogen-14 quadrupole resonance. In the case of an axially symmetric electric field gradient tensor, we observed broadening or Zeeman doublets. By contrast, in the general case (no symmetry), we demonstrated the possibility to define the electric field gradient tensor from the line shape of a single transition instead of two transitions ( without static magnetic field ). This result reduces by half the time required for the characterization of a new nitrogen molecule.

Chez la levure fissipare S. pombe, certains gènes méiotiques sont exprimés de façon constitutive pendant la croissance végétative. Cependant, pour empêcher le déclenchement prématuré de la méiose, la cellule a mis en place un système de dégradation sélective des ARN messagers correspondant. La protéine de liaison à l’ARN Mmi1, de la famille YTH, reconnaît des répétitions de motifs spécifiques (UNAAAC) au sein des transcrits et dirige ces derniers vers la dégradation par l’exosome nucléaire. Lors de l’entrée en méiose, Mmi1 est séquestré par un complexe ribonucléoprotéique comprenant la protéine de méiose Mei2 et l’ARN noncodant meiRNA, ce qui permet aux ARNm méiotiques d’être exportés et traduits. Au cours de ma thèse, je me suis intéressé au rôle de Mmi1 dans la dégradation des transcrits méiotiques pendant la croissance végétative. En accord avec des études récentes, nos travaux montrent que Mmi1 interagit étroitement avec le complexe Ccr4-Not de déadenylation des ARNm. Cette interaction est fonctionnelle car Ccr4-Not est requis pour la dégradation des ARNs méiotiques. De façon surprenante, cependant, l’activité de déadénylation n’est pas requise. Nos analyses génétiques et biochimiques suggèrent que la sous-unité E3 ubiquitin ligase Mot2 de Ccr4-Not ubiquitine un pool de l’inhibiteur de Mmi1, la protéine Mei2, pour faciliter sa dégradation par le protéasome. Cette voie de régulation permet de maintenir la fonction de Mmi1 et donc la répression des ARNm méiotiques dans les cellules mitotiques. Ainsi, Mmi1 a une double fonction: cibler les ARNm méiotiques vers la dégradation par l’exosome nucléaire, et recruter Ccr4-Not pour ubiquitiner et dégrader son propre inhibiteur Mei2. Ces résultats mettent également en avant un nouveau rôle pour la sous-unité E3 ligase du complexe Ccr4-Not dans le contrôle de la différenciation sexuelle. Des expériences supplémentaires indiquent que le domaine YTH de liaison à l’ARN de Mmi1, mais pas l’ARN noncodant meiRNA, est requis pour la dégradation de Mei2. De façon importante, nos données révèlent aussi que le domaine YTH de Mmi1 a un rôle clé dans l’interaction avec Mei2. Ceci suggère fortement que le domaine YTH agit comme un module bifonctionnel, permettant la liaison non seulement aux ARNs méiotiques mais aussi aux protéines comme Mei2. Nous discutons ces résultats dans le contexte de la littérature actuelle et proposons un nouveau modèle du contrôle de la différenciation sexuelle par le système Mmi1-Mei2. / In the fission yeast S. pombe, several meiotic mRNAs are constitutively expressed during the mitotic cell cycle. In order to avoid untimely entry into meiosis, cells have adopted a degradation system that selectively eliminates the corresponding mRNAs. The YTH family RNA-binding protein Mmi1 recognizes specific sequence motifs within these transcripts (UNAAAC) and allows their targeting to the nuclear exosome for degradation. Upon entry into meiosis, Mmi1 is sequestered in a ribonucleoprotein complex, composed by the meiotic protein Mei2 and the non-coding RNA meiRNA, allowing meiotic mRNAs to be exported and translated. During my PhD studies, I focused my interest on the role of Mmi1 in the degradation of meiotic transcripts during vegetative growth. In accord with recent studies, our results show that Mmi1 stably interacts with the mRNA deadenylation complex Ccr4-Not. This interaction has a functional relevance since Ccr4-Not is involved in the degradation of meiotic mRNAs. Surprisingly, however, the deadenylation activity is not required. Our genetic and biochemical analyses indicate that the E3 ubiquitin ligase Mot2, subunit of the Ccr4-Not complex, ubiquitinate a pool of the inhibitor of Mmi1, the Mei2 protein, to favor its degradation by the proteasome. This regulatory mechanism ensures the maintenance of Mmi1 in a functional state, leading to the persistent repression of meiotic mRNAs in mitotic cells. Thus, Mmi1 has a dual role: in nuclear mRNA surveillance, by targeting meiotic transcripts for degradation by the exosome, and in protein degradation, by recruiting Ccr4-Not to its own inhibitor Mei2. These results have also revealed a novel role for the ubiquitin ligase activity of the Ccr4-Not subunit Mot2 in the control of sexual differentiation in fission yeast. Our supplemental results indicate that the YTH RNA-binding domain of Mmi1, but not the non-coding RNA meiRNA, is required for the degradation of Mei2. Remarkably, our results also revealed that the YTH domain of Mmi1 has a key role in the interaction with Mei2. This strongly suggests that the YTH domain acts as a bifunctional module, allowing the binding not only to meiotic RNAs but also to proteins, such as Mei2. We discuss these results within the context of the current literature and we propose a novel model for the control of sexual differentiation by the Mmi1-Mei2 system.

The diploma thesis is focused on the features description of electronics switches for digital switching arrays and on the design of program for optimal calculation of switching points and the figure of switches in digital switching arrays investigation. The electronics switches types, used for time circuit separation, are described in the preamble. These switches are the base of digital switching arrays and in principal two types are defined: the switch S and switch T. The switch S allows the interconnection only of the same channel intervals from incoming circuit with random outgoing circuit. The switch S is being used in multistage switching arrays in combination with the switches T because it can not be used separately. The switch T allows exchanging the time position of incoming circuit to different time position of outgoing circuit depending on connection needs. The time switch can substitute the space switch under specific work conditions. In practice, the time switch with controlled reading and writing is used. The following part of diploma thesis is focused on the designs and calculations of optimal switching points of digital switching array which is the executive unit of switching systems. These systems directly interconnect the signals from digital multiplexes and make the basic assumptions for telecommunication networks integration. The digital switching array means the equipment which is able to connect the channels of digital multiplexes carrying the information in encoding form. The multiplexes are the most often with pulse coded modulation or adaptive delta modulation. The digital switching arrays are divided into the time and space one. The switching arrays of digital switching systems can be made by time switching array T whose realization is limited to specific capacity or by the connection of multistage arrays. Single stages sequenced one behind each other are made by the switches T and S. The space array S does not allow making the digital switching array of switching centre. The program which determines possible proposals of switching arrays from defined figure of inputs and calculates the optimal figure of switching points and switches is a part of diploma thesis.

The main topic of this Master's Thesis is design and implementation of automatic range switch AC/DC Transfer Standart Fluke 792A. In the first part is introduce and description of character and the parameters AC/DC trasfer Standart Fluke 792A and design of the Automatic range switch for this equipment. In the next part is introduce design and description of realize automatic switch control unit it has comunication faculty witch PC over GPIB bus. In the finish part is show of the theoretic description for GPIB bus and her realization with helped microcontroller Atmega16.

Title: Boolean techniques in Knowledge representation Author: Miloš Chromý Department: Department of Theoretical Computer Science and Mathematical Logic Supervisor: Doc. RNDr. Ondřej Čepek, Ph.D., Department of Theoretical Com- puter Science and Mathematical Logic Abstract: In this thesis we will investigate switch-list representations of Boolean function and we will explore the biclique satisfiable formulas. Given a truth table representation of a Boolean function f the switch-list rep- resentation of f is a list of Boolean vectors from the truth table which have a different function value than the preceding Boolean vector in the truth table. We include this type of representation in the Knowledge Compilation Map [Dar- wiche and Marquis, 2002] and argue that switch-lists may in certain situations constitute a reasonable choice for a target language in knowledge compilation. First, we compare switch-list representations with a number of standard repre- sentations (such as CNF, DNF, and OBDD) with respect to their relative suc- cinctness. As a by-product of this analysis we also give a short proof of a long standing open question from [Darwiche and Marquis, 2002], namely the incom- parability of MODS (models) and PI (prime implicates) representations. Next, using the succinctness result between...

Prior research shows that adult children of divorce (ACD) exhibit higher levels of perceived stress than adult children of marriage (ACM), and thus, potentially lower tolerance to stress. The comparison of ACD/ACM in Sweden has not been sufficiently studied. Hence, the present study aims to examine stress management among ACD and ACM, in terms of cognitive performance under different levels of induced stress, and how it correlates to self-ratings of stress. The final sample consisted of 101 adult participants (39 ACD and 62 ACM), and the mean age was 28 years old (41 males and 60 females). The result showed no difference in stress management between ACD and ACM, and their cognitive performance was not positively correlated with self-ratings of stress. However, ACD had a faster response time (RT) in all tests, even though this difference was not significant. At this time, ACD and ACM experience equally high levels of stress, as the Covid-19 pandemic might have influenced the outcome. Future research should collect more data of ACD in Sweden of other measurements of stress. / Tidigare forskning visar att vuxna skilsmässobarn (ACD) uppvisar högre nivåer av upplevd stress än vuxna med gifta föräldrar (ACM), och skulle därför potentiellt ha lägre stresstolerans. Jämförelsen mellan ACD/ACM i Sverige har inte blivit tillräckligt studerad. Därför har denna studie som mål att undersöka stresshantering bland ACD/ACM, i form av kognitiv prestanda under olika nivåer av inducerad stress, och hur det korrelerar till självskattningar av stress. Det slutgiltiga deltagarurvalet bestod av 101 myndiga deltagare (39 ACD och 62 ACM), varav medelåldern var 28 år, (41 män och 60 kvinnor). Resultatet visar att det inte var några signifikanta skillnader i stresshantering mellan ACD och ACM, och var inte positivt korreleradtill självskattningar av stress. Men, ACD hade en snabbare responstid (RT) i samtliga tester trots att resultatet inte var signifikant. Just nu, upplever ACD och ACM lika höga nivåer av stress, då Covid-19 pandemin kan ha influerat resultatet. Framtida forskning borde samla in mer data kring ACD i Sverige från andra mätningar av stress.

This MSc Thesis focuses on principles, practical performability and security against four attacks used in contemporary local-area networks: CAM Table Overflow capable of capturing traffic in switched networks, ARP Man-in-the-Middle, whose target is to redirect or modify traffic and against two variants of VLAN Hopping attack allowing a hacker to send and capture data from VLANs he has no access to.

Current FPGA technology has advanced to the point that useful embedded SoPCs can now be designed. The Real Time Processor (RTP) project at Brigham Young University leverages the advances in FPGA technology with a system architecture that is customizable to specific applications. A simple real-time processor has been designed to provide support for a hardware-assisted real-time operating system providing fast context switches. As part of the hardware RTOS, the following have been implemented in hardware: scheduler, register banks, mutex, semaphore, queue, interrupts, event, and others. A novel circuit called the Task-Resource Matrix has been created to allow fast inter/intra processor communication and synchronization.

This thesis presents a solution enabling lower losses in hydraulic actuator systems. A mobile fluid power system often contains several different actuators supplied with a single load sensing pump. One of the main advantages is the need of only one system pump. This makes the fluid power system compact and cost-effective. A hydraulic load often consists of two ports, e.g. motors and cylinders. Such loads have traditionally been controlled by a valve that controls these ports by one single control signal, namely the position of the spool in a control valve. In this kind of valve, the inlet (meter-in) and outlet (meter-out) orifices are mechanically connected. The mechanical connection makes the system robust and easy to control, at the same time as the system lacks flexibility. Some of the main drawbacks are The fixed relation between the inlet and outlet orifices in most applications produce too much throttling at the outlet orifice under most operating conditions. This makes the system inefficient. The flow directions are fixed for a given spool position; therefore, no energy recuperation and/or regeneration ability is available. In this thesis a novel system idea enabling, for example, recuperation and regeneration is presented. Recuperation is when flow is taken from a tank, pressurized by external loads, and then fed back into the pump line. Regeneration is when either cylinder chambers (or motor ports) are connected to the pump line. Only one system pump is needed. Pressure compensated (load independent), bidirectional, poppet valves are proposed and utilized. The novel system presented in this thesis needs only a position sensor on each compensator spool. This simple sensor is also suitable for identification of mode switches, e.g. between normal, differential and regenerative modes. Patent pending. The balance of where to put the functionality (hardware and/or software) makes it possible to manoeuvre the system with maintained speed control in the case of sensor failure. The main reason is that the novel system does not need pressure transducers for flow determination. Some features of the novel system: Mode switches The mode switches are accomplished without knowledge about the pressures in the system Throttle losses With the new system approach, choice of control and measure signals, the throttle losses at the control valves are reduced Smooth mode switches The system will switch to regenerative mode automatically in a smooth manner when possible Use energy stored in the loads The load, e.g. a cylinder, is able to be used as a motor when possible, enabling the system to recuperate overrun loads The system and its components are described together with the control algorithms that enable energy efficient operation. Measurements from a real application are also presented in the thesis.