Techn. University, Diss., 2005--München.

Univ., Diss., 2005--Frankfurt (Main) / Zsfassung in dt. und engl. Sprache

La thèse est consacrée à la construction et à l'étude des espaces de modules des connexions holomorphes algébroïdes de Lie sont étudiés.On commence par une classification des faisceaux d'algèbres filtrées quasi-polynômiales sur une variété complexe lisse projective en termes d'algébroïdes de Lie holomorphes et de leurs classes de cohomologie. Cela permet de construire les espaces de modules de connexions holomorphes agébroïdes de Lie par le formalisme des Lambda-modules de Simpson.Par ailleurs, on étudie la théorie des déformations de telles connexions, et on calcule le germe de leur espace de modules dans le cas de rang deux, lorsque la variété de base est une courbe. / The thesis is concerned with the consturction and the sudy of moduli spaces of holomorphic Lie algebroid connections. It provides a classification of sheaves of almost polynomials filtered algebras on a smooth projective complex variety in terms of holomorphic Lie algebroids and their cohomology classes. This permits to build moduli spaces of holomorphic Lie agebroid connections via Simpson's formalism of Lambda-modules. Furthermore, the deformation theory of such connections is suried, and the germ of their moduli spaces in the rank two case is computed when the base variety is a curve.

Bacteriophage ë has been used as a model replicon system for forty years. While the basic ë replication initiation scheme has been elucidated for several decades, many aspects of the mechanisms are unclear. I wished to study two unanswered issues in ë replication initiation. </p><p>Replication initiation of E. coli and ë each depend upon a protein generally called a licensing factor, which brings the DnaB helicase protein to the origin site to begin DNA synthesis. The licensing factors are the products of host gene dnaC and ë gene P. The synthesis of P from ë DNA in an E. coli cell can competitively interfere with DnaC activity needed for E. coli replication initiation. I wished to learn more about what happens to a host cell when exposed to extended P expression. Previous studies in this laboratory suggested that i) the continuous expression of P was tolerated by a subset of exposed cells and that ii) host defects mapping to dnaB could suppress the effect of extended P expression (P-lethality). I used DNA sequencing to determine if these suppressor mutations were within dnaB. I screened known host mutations for their influence on P-lethality. In summary: E. coli strains with GrpD55 and GrpA80 defects were found to each have two point mutations within their dnaB genes. I was unable to isolate mutations within P that suppressed P-lethality and instead obtained regulatory mutations preventing wild type P expression. Two of these sequenced mutations showed that a cI[Ts] lambda repressor was reverted to cI wild type, blocking P expression at all assay temperatures. P-lethality was reversible in cells exposed to P for up to five hours, causing me to suggest that P-Interference be used in place of the term P-lethality. A non-inducible allele of lexA prevented P-mediated cellular filamentation and enhanced P-Interference. This suggests that induction of the SOS response helps cells to tolerate extended P expression. A host strain containing a defective ClpXP protease significantly enhanced cellular sensitivity to P-Interference. This suggests an important role for the ClpXP chaperone-protease complex in degradation of P and cellular resistance to P expression. I present models to explain the P-Interference Phenotype.</p><p>Recent reports have re-opened the possibility that the tO-oop-pO element influences ë DNA replication initiation. I have also been investigating this possibility. I found that a plasmid with tO-oop-pO (the terminator, nucleotide sequence and promoter for OOP RNA) and orië DNA sequence was inhibitory to the development of repë phages, and designated this the Inhibition Phenotype (IP). In pursuing the mechanism for this inhibition, I mutated the tO-oop-pO and orië elements. I found that the expression of the 77nt OOP RNA transcript and the presence of four 18 base pair repeats (iterons) within orië were required for the IP. I isolated spontaneous phage mutants, resistant to the IP. I determined that singly infected cells were sensitive to the IP but that multiply infected cells escaped the IP. I propose that the IP to repë phage development is directed to the initial or theta mode of ë replication initiation. I found that the theta-mode of ë replication initiation can be bypassed, likely via recombination between multiple phage genomes within a singe cell. I propose models to explain the IP and also suggest a role for OOP RNA in the regulation of ë DNA replication.

Bacteriophage ë has been used as a model replicon system for forty years. While the basic ë replication initiation scheme has been elucidated for several decades, many aspects of the mechanisms are unclear. I wished to study two unanswered issues in ë replication initiation. </p><p>Replication initiation of E. coli and ë each depend upon a protein generally called a licensing factor, which brings the DnaB helicase protein to the origin site to begin DNA synthesis. The licensing factors are the products of host gene dnaC and ë gene P. The synthesis of P from ë DNA in an E. coli cell can competitively interfere with DnaC activity needed for E. coli replication initiation. I wished to learn more about what happens to a host cell when exposed to extended P expression. Previous studies in this laboratory suggested that i) the continuous expression of P was tolerated by a subset of exposed cells and that ii) host defects mapping to dnaB could suppress the effect of extended P expression (P-lethality). I used DNA sequencing to determine if these suppressor mutations were within dnaB. I screened known host mutations for their influence on P-lethality. In summary: E. coli strains with GrpD55 and GrpA80 defects were found to each have two point mutations within their dnaB genes. I was unable to isolate mutations within P that suppressed P-lethality and instead obtained regulatory mutations preventing wild type P expression. Two of these sequenced mutations showed that a cI[Ts] lambda repressor was reverted to cI wild type, blocking P expression at all assay temperatures. P-lethality was reversible in cells exposed to P for up to five hours, causing me to suggest that P-Interference be used in place of the term P-lethality. A non-inducible allele of lexA prevented P-mediated cellular filamentation and enhanced P-Interference. This suggests that induction of the SOS response helps cells to tolerate extended P expression. A host strain containing a defective ClpXP protease significantly enhanced cellular sensitivity to P-Interference. This suggests an important role for the ClpXP chaperone-protease complex in degradation of P and cellular resistance to P expression. I present models to explain the P-Interference Phenotype.</p><p>Recent reports have re-opened the possibility that the tO-oop-pO element influences ë DNA replication initiation. I have also been investigating this possibility. I found that a plasmid with tO-oop-pO (the terminator, nucleotide sequence and promoter for OOP RNA) and orië DNA sequence was inhibitory to the development of repë phages, and designated this the Inhibition Phenotype (IP). In pursuing the mechanism for this inhibition, I mutated the tO-oop-pO and orië elements. I found that the expression of the 77nt OOP RNA transcript and the presence of four 18 base pair repeats (iterons) within orië were required for the IP. I isolated spontaneous phage mutants, resistant to the IP. I determined that singly infected cells were sensitive to the IP but that multiply infected cells escaped the IP. I propose that the IP to repë phage development is directed to the initial or theta mode of ë replication initiation. I found that the theta-mode of ë replication initiation can be bypassed, likely via recombination between multiple phage genomes within a singe cell. I propose models to explain the IP and also suggest a role for OOP RNA in the regulation of ë DNA replication.

The template system of C++ is expressive enough to allow the programmer to write programs which are evaluated during compile time. This can be exploited for example in generic programming. However, these programs are very often hard to write, read and maintain. We introduce a simple translation from lambda calculus into C++ templates and show how it can be used to simplify C++ metaprograms. This variation of lambda calculus is then extended with Hindley-Milner type system and various other features (Haskell-like syntax, user-defined data types, tools for interaction with existing C++ template code and so on). We then build a compiler capable of transforming programs written in this language into C++ template metaprograms. Powered by TCPDF (www.tcpdf.org)

Goal of this work is design and create extension data acquisition unit for existing system of heating boiler. Work is divided to theoretical and practical part. In theoretical part is mentioned methods of measuring temperature. Methods of measuring flue gas and placement of boilers into different classes according to standard ČSN EN 303-5:2013. The practical part deals with the design of schematic circuit for measuring the required parameters (lambda probe, thermocouple, measuring the light intensity using the photo-resist). Mechanical cover, testing created board under real conditions and the involvement of extension board into existing system of boiler. When commissioning the first version of the board appeared errors that were removed in the second version. In attempts to improve the operations of two boilers were found errors leading to the impossibility of any improvements.

Deoxyribonucleic acid isolated from bacteriophage lambda can infect Escherichia coli K12 in the presence of adsorbed helper phage (Kaiser and Hogness, 1960; Kaiser, 1962). The manner in which lambda DNA enters the cell and the possible role of helper phage in the penetration process is still not clear. Kinetic studies conducted in this laboratory during the initial stages of infection by lambda DNA demonstrate a requirement for helper function during the penetration of an infectious molecule. Further investigation into this problem is needed and was the major objective of this study.

No description available.

La fixation du bactériophage Lambda sur son récepteur cellulaire, LamB, est dûe à une protéine de sa queue appelée GpJ. Le but des travaux est d’étudier l’intéraction entre le bactériophage Lambda et LamB à travers l’étude du complexe entre LamB et GpJ exprimée en protéine de fusion. Pour ce faire, deux protéines de fusion sont utilisées : MBP-gpJ et HisgpJ. MBP-gpJ est une protéine de fusion entre la Maltose Binding Protéine et l’extrêmité Cterminale de la protéine GpJ (résidu 684 à 1132), grâcieusement fournie par le Pr. Charbit (Paris, France). Grâce à la Technique du Film Noir (BLM), il a été permis d’observer que MBP-gpJ, après expression dans E.coli et purification, intéragit grâce au fragment de GpJ avec l’extrêmité extracellulaire de LamB. Cette intéraction se traduit par un blocage complet et réversible des canaux de LamB sauvage, mais également de mutants: LamB de Shigella sonnei, LamB Y118G et LamB D4+D6+D9v. Afin d’obtenir des informations sur la liaison de LamB avec uniquement le fragment de GpJ sans la partie MBP, une autre protéine de fusion a été réalisée: His-GpJ. His-gpJ représente l’extrêmité C-terminale de GpJ (684-1132) en fusion avec un 6×Histidine-tag. Cette protéine est exprimée sous forme de corps d’inclusion dans E.coli. Après purification et renaturation, une protéine de nouveau soluble peut être obtenue. Lors d’expériences de Film Noir, His-gpJ intéragit certes avec LamB, mais n’induit pas le blocage des canaux comme précedemment observé après ajout de MBP-gpJ. En parallèle, la formation d’un complexe entre His-gpJ et LamB sauvage, ainsi que de mutants a pu être confirmée au travers de travaux de SDS-PAGE et d’immunodétection par la présence de bandes de masse moléculaire élevée. L’utilisation de mutants de LamB a par ailleurs permis d’essayer d’identifier la partie de LamB impliquée dans l’interaction avec le fragment C-terminal de GpJ, qui se révèle être différente de celle de GpJ dans la queue du bactériophage Lambda. Mots clés: bactériophage Lambda, gpJ, LamB, technique du film noir (BLM), immunodétection. / The bacteriophage Lambda is a virus which infects bacteria carrying LamB protein in their outer membrane. GpJ, a protein of the tail of the phage, is involved in the binding to LamB. The study of the interaction between GpJ expressed as fusion protein and LamB was performed in order to investigate the interaction between the bacteriophage Lambda and LamB. The fusion proteins are called MBP-gpJ and His-gpJ. MBP-gpJ is a chimeric protein representing Maltose Binding Protein connected to the Cterminal part of the GpJ protein (residue 684 until 1132), graciously given by Pr. Charbit (Paris, France). MBP-gpJ, expressed in E.coli and purified, bound to the exoplasmic side of LamB and LamB variants in planar lipid bilayer experiments and allowed a complete and reversible blockage of LamB channels. In order to obtain data about the binding of the GpJ fragment alone to LamB, an other fusion protein without MBP was created, called His-gpJ. His-gpJ is the C-terminal part of GpJ (684-1132) in fusion with a 6×Histidine-tag, produced as insoluble form in E.coli. After renaturation, a soluble protein can be obtained. Without MBP, the GpJ fragment still bound to LamB in planar lipid bilayer experiments, but did not block significantly its channels, as previously observed after addition of MBP-gpJ. The interaction between His-gpJ and LamB or LamB mutants was also demonstrated on SDSPAGE and immunodetection by the presence of high molecular mass bands. Furthermore, the use of variants of lamB allowed to demonstrate that the C-terminal fragment of GpJ does not bind to the same area on the surface of LamB than GpJ involved in the tail of the Lambda phage.