L'épiderme est un tissu stratifié, majoritairement constitué de kératinocytes qui forme la première barrière de l'organisme contre les agressions extérieures. Après blessure cutanée, la migration des kératinocytes est une phase cruciale de la cicatrisation. Le comportement des kératinocytes est placé sous le contrôle des molécules de la matrice extracellulaire ainsi que par les facteurs solubles (facteurs de croissance et cytokines..) sécrétés dans le microenvironnement. Les cellules résidentes ou recrutées sur le site de lésion libèrent également des nucléotides extracellulaires (ATP, UTP) dans l'environnement des kératinocytes. Dans ce travail de thèse, nous avons examiné l'impact des nucléotides extracellulaires et du récepteur purinergique P2Y2 sur la migration des kératinocytes et sur l'activité motogénique de deux facteurs de croissance, l'IGF-I et de l'EGF. Dans un premier temps, nous avons pu montrer que l'activation de P2Y2 et de la protéine hétérotrimérique Gαq inhibe l'activité de l'isoforme p110α de la PI3K sur des cellules stimulées par l'IGF. Cette inhibition de la voie PI3K/Akt aboutit à une perturbation de la mobilisation de la cortactine et de la formation des lamellipodes ainsi qu'une diminution de la vitesse de migration des kératinocytes. Dans un second temps, nous avons mis en évidence que l'activation de P2Y2 inhibe l'activation de la voie ERK1/2 par l'EGF en inhibant la phosphorylation des protéines MEK1/2, ERK1/2 et p90RSK. Nous avons établi que la conséquence de cette inhibition est la stabilisation des hémidesmosomes / The epidermis is a stratified tissue, mainly composed of keratinocytes, that forms the first barrier of the organism. When skin injury occurs, the epidermis structure is altered and many signalling pathways are activated in order to re-establish its homeostasis. Among these signalling pathways, the PI3K and MAPK ERK1/2 pathways play key roles by controlling keratinocyte migration and proliferation. The aim of this thesis was to analyse the regulation of these two signalling pathways by extracellular nucleotides, acting through purinergic receptors P2Y2 and the heterotrimeric Gαq protein and to evaluate the impact of this receptor on keratinocyte migration. Firstly, we showed that P2Y2 receptor activation inhibits PI3K p110α isoform and consequently alters keratinocyte cell shape and migration. Additionally, we showed that purinergic signalling activation inhibits EGF-induced ERK1/2 pathway activation by inhibiting the phosphorylation of MEK1/2, ERK1/2 and p90RSK proteins. As a consequence, P2Y2 stabilizes α6β4 integrin localisation into hemidesmosome-like structures and inhibits keratinocyte migration. The involvement of purinergic signalling pathway in regulation of different signalling events suggests that it may play a central role in regulation of cellular events that occurred during skin wound healing process. Moreover, our present data in association with those of the literature show that extracellular nucleotides can act as a double-edged sword in the regulation of cell migration: either activate or block cell migration in a striking cell-specific manner.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Made available in DSpace on 2014-06-12T16:00:02Z (GMT). No. of bitstreams: 2 arquivo5819_1.pdf: 1022780 bytes, checksum: 817e10825cb544dad97eed36627fdd51 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Uma abordagem formal e crucial na especificação e desenvolvimento de sistemas complexos. Inspirado pela engenharia, o desenvolvimento de software deve preterir a abordagem empirica e seguir uma abordagem estruturada, formal, passível de repetição e prova face ao advento de sistemas mais complexos, paralelos e concorrentes. Este trabalho apresenta uma extensão conservativa de OhCircus, uma linguagem de especificação oncorrente, que integra CSP, Z, orientação a objetos e um calculo de re- finamento. Esta extensão suporta a definição de heranca de processo, onde uxo de controle, operações e componentes de estado em um superprocesso, podem ser reusados por seus subprocessos. Neste trabalho nos apresentamos a gramatica estendida de OhCir- cus, acompanhada por um conjunto de regras de tipos que lidam com as novas construções da linguagem. Nos apresentamos, em termos da Unifying Theories of Programming definida por Hoare e He, a semântica formal de heranca de processo e suas construções de suporte. A principal contribuição deste trabalho e um conjunto, formalmente provado, de leis algebricas que lidam com herança de processo. Nós também explanamos informalmente como essas leis podem contribuir para uma teoria de completude para OhCircus. Finalmente nossas leis são exercitadas atraves de um estudo de caso

This study exploits the recently-issued Uncertain Tax Position Statement (Schedule UTP) to examine the effect of mandatory disclosures of tax uncertainty to tax authorities on firms' reporting decisions. Schedule UTP requires firms to disclose federal income tax positions to the Internal Revenue Service that have been classified as 'uncertain' for financial reporting purposes. In showing how Schedule UTP disclosure requirements affect private and public reporting decisions, I provide insights into the usefulness of these disclosures. Using confidential tax return data and public financial statement data, I find that after imposition of Schedule UTP reporting requirements, firms report lower financial reporting reserves for uncertain income tax positions, but do not claim fewer income tax benefits on their federal tax returns. These findings suggest some firms changed their financial reporting for uncertain tax positions to avoid Schedule UTP reporting requirements without changing the underlying positions. The effect is concentrated among firms with greater business complexity, whose business operations facilitate tax planning strategies that are more difficult for the IRS to identify. More broadly, my results imply private disclosures of tax uncertainty can affect the informativeness of public disclosures of tax uncertainty. / text

Detta arbete har utförts i samarbete med Saab Seaeye och rör deras undervattensfarkost Sabertooth. En lokal GPS (global positioning system) genererar en PPS-signal (pulse per second) som används till att synkronisera klockor runtom i farkosten. Om denna signal har för hög överlagrad störning så kommer inte enheter fungera önskvärt. Farkosten ska klara djup ner till 3000 m, varför elektroniken placeras tätt i en tryckbehållare, vilket leder till en störande miljö. Dessutom ska inte redan existerande delar av systemet störas ut om farkosten expanderas genom att koppla in fler enheter. Arbetets syfte var att hitta källan till störningar på PPS-signalen samt undersöka och verifiera metoder som skyddar mot dessa störningar. De metoder som har undersökts är differentiell signalering (RS-422), optoisolering samt buffersteg. De kabeltyper som har undersökts är koaxialkabel, tvinnade kablar utan skärm (UTP) och tvinnade kablar med skärm (STP) som jordas endast hos sändare eller hos både sändare och mottagare. Den störande miljön är fortfarande ett problem i farkosten, men genom användning av antingen koaxialkabeln eller STP så lyckades störningarna reduceras markant. Att även isolera kommunikationsenheten med resterande system och implementera kraftfulla drivkretsar ger möjligheten till expandering utan att påverka redan existerande enheter.

The master’s thesis is focused on creating a company’s computer network and a plan of its implementation. The plan is based on an analysis of the new company building in which the network is supposed to be implemented and consequently specifies specific procedures and elements that will be used during the process of implementation. The thesis includes technical documentation , cost calculation and work plan necessary for the realization of the network.

Recent studies show that angiotensin II (AngII) can act from within the cell, possibly via intracellular receptors pharmacologically different from typical plasma membrane AngII receptors. The role of this intracellular AngII (AngIIi) is unclear. Besides direct effects of AngIIi on cellular processes one could hypothesise a possible role of AngIIi in modulation of cellular responses induced after heterologous receptor stimulation. We therefore examined if AngIIi influences [Ca2+]i in A7r5 smooth muscle cells after serotonin (5HT) or UTP receptor stimulation. Application of AngIIi using liposomes, markedly inhibited 45Ca2+ influx after receptor stimulation with 5HT or UTP. This inhibition was reversible by intracellular administration of the AT1-antagonist losartan and not influenced by the AT2-antagonist PD123319. Similar results were obtained in single cell [Ca2+]i measurements, showing that AngIIi predominantly influences Ca2+ influx and not Ca2+ release via AT1-like receptors. It is concluded that AngIIi modulates signal transduction activated by heterologous receptor stimulation.

Model Driven Development (MDD) and Model Based Testing (MBT) are gaining inroads individually for their application in embedded software engineering projects. However, their full-edged and integrated usage in real-life embedded software engineering projects (e.g. industrially relevant examples) and executing MBT in resource constrained embedded systems (e.g. 16 bit system/64 KiByte memory) are emerging fields. Addressing the aforementioned gaps, this thesis proposes an integrated model-based approach and test framework for executing the model-based test cases, with minimal overhead, in embedded systems. Given a chosen System Under Test (SUT) and the system design model, a test framework generation algorithm generates the necessary artifacts (i.e., the test framework) for executing the model-based test cases. The main goal of the test framework is to enable test automation and test case execution at the host computer (which executes the test harness), thereby only the test input data is executed at the target. Significant overhead involved in interpreting the test data at the target is eliminated, as the test framework makes use of a target debugger (communication and decoding agent) on the host and a target monitor (software-based runtime monitoring routine) in the embedded system. In the prototype implementation of the proposed approach, corresponding (standardized) languages such as the Unified Modeling Language (UML) and the UML Testing Profile (UTP) are used for the MDD and MBT phases respectively. The applicability of the proposed approach is demonstrated using an experimental evaluation (of the prototype) in real-life examples. The empirical results indicate that the total time spent for executing the test cases in the target (runtime-time complexity), comprises of only the time spent to decode the test input data by the target monitor and execute it in the embedded system. Similarly, the only memory requirement in the target for executing the model-based test cases in the target is that of the software-based target monitor. A quantitative comparison on the percentage change in the memory overhead (runtime-memory complexity) for the existing approach and the proposed approach indicates that the existing approach (e.g. in a MDD/MBT tool-Rhapsody), introduces approximately 150% to 350% increase in memory overhead for executing the test cases. On the other hand, in the proposed approach, the target monitor is independent of the number of test cases to be executed and their complexity. Hence, the percentage change in the memory overhead for the proposed approach shows a declining trend w.r.t the increasing code-size for equivalent application scenarios (approximately 17% to 2%). Thus, the proposed test automation approach provides the essential benefit of executing model- based tests, without downloading the test harness in the target. It is demonstrated that it is feasible to execute the test cases specified at higher abstraction levels (e.g. using UML sequence diagrams) in resource constrained embedded systems and how this may be realized using the proposed approach. Further, as the proposed runtime monitoring mechanism is time and memory-aware, the overhead parameters can be accommodated in the earlier phases of the embedded software development cycle (if necessary) and the target monitor can be included in the final production code. The aforementioned advantages highlight the scalability, applicability, reliability and superiority of the proposed approach over the existing methodologies for executing the model-based test cases in embedded systems.

This master’s thesis is concerned with analysis of cabling and cabling systems in data center and with their projection as follows. The part of the work is aimed at the measurement parameters of metal cables which are used in data center with noise. The first part is focused on analyzing the structure of the data center and cabling used in it. The structure of the data center is based on the TIA-942 and consists of an entrance room, main distribution area MDA, horizontal distribution area HDA , zone distribution area ZDA and the equipment distribution area EDA. Divided into backbone cabling and horizontal cabling and use standard and pre-terminated cabling. The measurement results of structured metal cabling with noise are discussed in the next part. There were used these types of cables UTP, FTP and S/FTP. The measurement was performed in the electricity substation and in the laboratory of electromagnetic compatibility. The third part of this work deals with the actual design of structured cabling for the data center. In the first design we use the standard installation, the second preterminated cabling. For both types of installation cost statement is processed (CAPEX). Thesis is also completed with DC design drawings and rack drawings.