Under hostile conditions, bacteria elicit stress response. Such stress response is regulated by a secondary messenger called (p)ppGpp. (p)ppGpp is involved in wide range of functions such as GTP homeostasis, biofilm formation and cell growth. Its regulation and mode of action is not well understood. This work has been initiated with an aim to gain insights into the molecular basis of stress response. (p)ppGpp was discovered on the chromatogram of cell extract from starved E. coli cells. (p)ppGpp is synthesized and hydrolyzed by Rel/SpoT in Gram negative bacteria (such as E. coli), and by bifunctional enzyme called Rel in Gram positive bacteria (such as Mycobacteria). The obvious question that comes in our mind is how bifunctional Rel enzyme decides on synthesis or hydrolysis in Gram positive bacteria such as Mycobacterium? In our laboratory, it has been shown that N-terminal domain of Rel shows unregulated (p)ppGpp synthesis implying regulatory role of C-terminal domain. Also, concurrent increase in anisotropy of Rel C-terminal domain with the increase in concentration of pppGpp has been observed indicating the binding of pppGpp to the C-terminal domain. We performed Isothermal Calorimetry experiment to confirm that pppGpp binds with C-terminal domain of Rel enzyme. For identification of the binding region, small molecule analogue 8-azido-pppGpp has been synthesized. This analogue is UV-crosslinked with C-terminal domain of Rel and specificity of the interaction has been determined by gel based crosslinking experiments. Crosslinked protein has been subjected to the ingel¬trypsin digestion and analyzed by mass spectrometry. We identified two crosslinked peptides in the mass spectra of trypsin digest in case of the crosslinked protein where identity of the parent peptide is confirmed by MS-MS analysis. Site directed mutagenesis has been carried out based on the conservation of residues in the crosslinked peptides. Isothermal Calorimetry analysis has been done where Rel C-terminal domain mutants are titrated with pppGpp in order to detect any defect in binding due to the mutations. Mutations leading to the reduced binding affinity of pppGpp to Rel C-terminal domain have been introduced in the full length Rel protein and activity assays are carried out so as to evaluate the effects of mutations on synthesis and hydrolysis activity. In mutants, synthesis activity is found to be increased with the concomitant reduction in hydrolysis activity. This indicates the feedback loop where pppGpp binds to Rel C-terminal domain to regulate it own synthesis and hydrolysis. In E. coli, pppGpp binds to RNA polymerase and modulates the transcription. The region where it binds is controversial. In addition, whether ppGpp and pppGpp have different binding site on RNA polymerase is not known. The latter question becomes important in the light of evidence where differential regulation of transcription by ppGpp and pppGpp have been indicated. We found that ppGpp and pppGpp have an overlapping binding site on RNA polymerase. The 8-azido-ppGpp has been mapped on β and β’ subunits whereas binding site of 8-azido-pppGpp has been located on the β’ subunit. We observed that the 8-azido¬pppGpp labels RNA polymerase more efficiently than ppGpp. pppGpp can compete out ppGpp as illustrated by DRaCALA assay and gel based crosslinking experiment. However, the RNAP from B. subtilis does not bind to (p)ppGpp. (p)ppGpp is ubiquitous in bacteria but absent in mammals. Thus, blocking (p)ppGpp synthesis would impede the survival of bacteria without having any effect on humans. Recently, Relacin compound has been synthesized by another group in order to inhibit (p)ppGpp synthesis. The limitations of this compound are the requirement of high concentration (5mM) for inhibition and low permeability across the membrane. Taking hints from the latter compound, we acetylated the nd 2’, 3’ and 5’ position of ribose ring and benzoylated the 2position of guanine moiety in guanosine molecule. We observed significant inhibition of in vitro pppGpp synthesis and biofilm formation. More studies will be conducted in near future to test these compounds for their plausible functions. In collaboration with Prof. Jayaraman (Organic Chemistry, IISc), many artificial glycolipids are synthesized and tested for biological function. We observed that synthetic glycolipids exhibit a profound effect as inhibitors of the key mycobacterial functions. These analogs impede biofilm formation and can plausibly affect long term survival. Glycolipid analogs can compete with natural glycolipids, thus may help in understanding their functions. Our past and recent studies have showed that the synthetic glycolipids act as inhibitors of mycobacterial growth, sliding motility and biofilm formation. The major lacuna of these glycolipid inhibitors is the requirement of high concentration. Their inhibitions at nanomolar concentrations remain to be achieved. Issues surrounding the thick, waxy mycobacterial cell wall structures will continue to be the focus in manifold approaches to mitigate detrimental effects of mycobacterial pathogens. In chapter 1, introduction to the research work has been written and role of (p)ppGpp and its functions have been discussed. In chapter 2, novel binding site of pppGpp on Rel C-terminal domain and its regulatory role have been discussed. In chapter 3, differential binding of ppGpp and pppGpp to RNA polymerase has been discussed. In chapter 4, studies on natural and synthetic analogues of pppGpp have been presented. In chapter 5, synthetic glycolipids studies have been described. Chapter 6 summarizes all the chapters.

Made available in DSpace on 2014-12-17T14:56:19Z (GMT). No. of bitstreams: 1 JanEMGP_DISSERT.pdf: 3028317 bytes, checksum: 5eeb8ec6954b59f2853f263ffa4c4d9c (MD5) Previous issue date: 2014-05-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The area of research and development involving the PID tune of controllers is an active area in the academic and industrial sectors yet. All this due to the wide use of PID controllers in the industry (96% of all controllers in the industry is still PID). Controllers well tuned and tools to monitor their performance over time with the possibility of selftuning, become an item almost obligatory to maintain processes with high productivity and low cost. In a globalized world, it is essential for their self survival. Although there are several new tools and techniques that make PID tune, in this paper will explore the PID tune using the relay method, due its good acceptance in the industrial environment. In addition, we will discuss some techniques for evaluation of control loops, as IAE, ISE, Goodhart, the variation of the control signal and index Harris, which are necessary to propose new tuning for control loops that have a low performance. Will be proposed in this paper a tool for tuning and self tuning PID. Will be proposed in this paper a PID auto-tuning software using a relay method. In particular, will be highlighted the relay method with hysteresis. This method has shown tunings with satisfactory performance when applied to the didactic, simulated and real plants / O campo de pesquisa e desenvolvimento de softwares envolvendo a sintonia de controladores PID, ainda ? uma ?rea ativa dentro do meio acad?mico e industrial. Tudo isso devido ? larga utiliza??o de controladores PID na ind?stria (96% de todos os controladores na ind?stria ainda ? PID). Ter controladores bem sintonizados e com ferramentas que possam acompanhar seus desempenhos ao longo do tempo com a possibilidade de ressintoniz?-los, ou ainda autossintoniz?-los, passar a ser um item quase que obrigat?rio para manter processos com alta produtividade e baixo custo. J? que em um mundo globalizado, o n?vel mais acirrado de concorr?ncia entre as empresas, atualmente, est? no custeio e na produtividade. Apesar de existirem diversas novas t?cnicas e ferramentas que fazem sintonia de controladores PID, neste trabalho ser? explorada esta sintonia utilizando o m?todo do rel?, devido a sua boa aceita??o no ambiente industrial, simplicidade e robustez. Al?m disto, abordaremos algumas t?cnicas para avalia??o de desempenho de malhas de controle de processos, tais como IAE, ISE, Goodhart, Vari?ncia de sinais e ?ndice de Harris. Ser? proposta neste trabalho uma ferramenta de sintonia e autossintonia PID (usando o m?todo do rel?), em especial o m?todo do rel? com histerese. Este m?todo tem apresentado sintonias com desempenhos satisfat?rios quando aplicados em plantas simuladas e reais

Made available in DSpace on 2015-07-15T13:31:35Z (GMT). No. of bitstreams: 1 Rosana Carvalho S Ghignath.pdf: 1325892 bytes, checksum: 999e87698bcdbc3db8145689158550ad (MD5) Previous issue date: 2008-02-20 / This dissertation has as objective to study, in comparative perspective , the works of E?a de Queir?s the "trip" Reports - Egypt, Palestine and High Syria -, everybody published posthumously, and the novel The Relic, published in the author's life. It fits to illuminate that the Portuguese novelist undertook a trip to the East, specifically to Egypt and Palestine, in the middle of 1869, motivated by the inauguration of the Channel of Suez. The annotations done by E?a concerning the places that he knew, in odds papers, they were published firstly by its son Jos? Maria d? E?a de Queiroz, fifty seven years then, entitling them as Egypto. Trip notes (1926). In 1966, the novelist's daughter, Maria E?a de Queiroz de Castro, picked up more notes of this material, composing the book Free Leaves, of which they make part the reports on Palestine and on Syria. In these works they are the author's personal impressions in relation to the that he saw in those distant places paragens. The Relic is already work ficcional published in 1887. In this novel, the narrator-character's trip, Teodorico Raposo, is shown by the Medium East. When doing an comparative analysis among these written, it is noticed that the novelist took advantage of its oriental course to redraft fiction, journalistic and epistle texts. Starting from the reading of the " Reports of Trip " and d?A relic, this dissertation seeks to investigate mapear the eatern imaginary in the works queirosianas, aiming the novelist's insert in the context of the easstern European century XVIII, as well as the influences that the writer received from the main works of French artists that also traveled to the East, to example of Flaubert, Renan and Gautier. He makes himself a literary analysis still comparing the texts of the "Reports of trip" writings for E?a young with the novel The relic, written in the writer's full maturity. They guide this study the theories of the parody, of the intratextualidade and of the irony as structures of the satirical and revision speech, that, it is believed, according to this novel of E?a de Queir?s. / Esta disserta??o tem como objetivo estudar, em perspectiva comparatista, as obras de E?a de Queir?s os Relatos de viagem O Egito, A Palestina e Alta S?ria , todos publicados postumamente, e o romance A rel?quia, publicado em vida do autor. Cabe esclarecer que o romancista portugu?s empreendeu uma viagem ao Oriente, especificamente ao Egito e ? Palestina, em meados de 1869, motivado pela inaugura??o do Canal de Suez. As anota??es feitas por E?a acerca dos lugares que conheceu, em pap?is avulsos, foram publicadas primeiramente pelo seu filho Jos? Maria d? E?a de Queiroz, cinq?enta e sete anos depois, intitulando-os como Egypto. Notas de viagem (1926). Em 1966, a filha do romancista, Maria E?a de Queiroz de Castro, recolheu mais notas deste material, compondo o livro Folhas Soltas, do qual fazem parte os relatos sobre a Palestina e sobre a S?ria. Nestas obras est?o as impress?es pessoais do autor em rela??o ao que ele viu naquelas paragens distantes. J? A rel?quia ? obra ficcional publicada em 1887. Neste romance, mostra-se a viagem do narrador-personagem, Teodorico Raposo, pelo M?dio Oriente. Ao fazer uma an?lise comparatista entre estes escritos, percebe-se que o romancista se aproveitou do seu percurso oriental para reescrever textos ficcionais, jornal?sticos e epistolares. A partir da leitura dos Relatos de viagem e d?A rel?quia, esta disserta??o procura mapear o imagin?rio oriental nas obras queirosianas, apontando a inser??o do romancista no contexto do orientalismo europeu oitocentista, bem como as influ?ncias que o escritor recebeu das principais obras de artistas franceses que tamb?m viajaram ao Oriente, a exemplo de Flaubert, Renan e Gautier. Faz-se uma an?lise liter?ria comparando os textos dos Relatos de viagem escritos por E?a ainda jovem com o romance A rel?quia, escrito em plena maturidade do escritor. Orientam este estudo as teorias da par?dia, da intratextualidade e da ironia como estruturadoras do discurso sat?rico e revisionista, que conforma este romance de E?a de Queir?s.

In this thesis the novel concept of Sycophant Wireless Sensors (SWS) is introduced. A SWS network is a static ectoparasitic clandestine sensor network mounted incognito on a mobile agent using only the agent&rsquo / s mobility without intervention. SWS networks not only communicate with each other through mobileWireless Sensor Networks (WSN) but also cooperate with them to form a global hybrid Wireless Sensor Network. Such a hybrid network has its own problems and opportunities, some of which have been studied in this thesis work. Assuming that direct position measurements are not always feasible tracking performance of the sycophant using range only measurements for various communication intervals is studied. Then this framework was used to create a hybrid 2D map of the environment utilizing the capabilities of the mobile network the sycophant. In order to show possible applications of a sycophant deployment, the sycophant sensor node was equipped with a laser ranger as its sensor, and it was let to create a 2D map of its environment. This 2D map, which corresponds to a height dierent than the follower network, was merged with the 2D map of the mobile network forming a novel rough 3D map. Then by giving up from the need to properly localize the sycophant even when it is disconnected to the rest of the network, a full 3D map of the environment is obtained by fusing 2D map and tracking capabilities of the mobile network with the 2D vertical scans of the environment by the sycophant. And finally connectivity problems that arise from the hybrid sensor/actuator network were solved. For this 2 new connectivity maintenance algorithms, one based on the helix structures of the proteins, and the other based on the acute triangulation of the space forming a Gabriel Graph, were introduced. In this new algorithms emphasis has been given to sparseness in order to increase fault tolerance to regional problems. To better asses sparseness a new measure, called Resistance was introduced, as well as another called updistance.

In this thesis, it is aimed to make a study on Primary Schools of Rum Minority in Istanbul, and in light of this study, to define general principles for conservation studies on these schools. Rum Minority had an important part in social and cultural life in Istanbul and in late 19th Century, their impact in the city increased with their financial power, especially in Beyoglu. Increase in number of schools they built also occurred in the same timeline. Schools built in and after this term by Rum Minority were built as important public buildings of a minority group and possess strong authenticity, technical-artistic, socio-cultural and economical values. In order to decide which values, problems and potentials these buildings bear, a site survey study is done for this thesis. Primary Schools of Rum Minority in Istanbul are among strongest solid evidences of cultural diversity in Istanbul, and Turkey. While conserving these cultural assets, considering all their values, problems, and potentialities is vital. In addition to conservation studies, interpretation and presentation are also necessary steps for reintegration of these buildings to the city. This thesis performs as an effort made to document features and current state of these schools, decide their value, problems, and potentials / and defining general conservation principles for them.

Καθώς η Κοινωνία της Πληροφορίας αναπτύσσεται με ταχύτατους ρυθμούς, οι τεχνολογικές κατακτήσεις από το χώρο της επιστήμης των υπολογιστών και τηλεπικοινωνιών, αποτελούν σημαντικό κεφάλαιο σε αρκετούς επιμέρους τομείς του κοινωνικού βίου, ανάμεσα στους οποίους είναι και ο Πολιτισμός. Η πολιτισμική ποικιλομορφία του υπάρχοντος υλικού και η διάθεση για αξιοποίηση της επιπρόσθετης εκπαιδευτικής του αξίας, σε συνδυασμό με την απαίτηση για διάσωση των πρωτότυπων έργων, συνθέτει ένα πολύπλοκο τεχνολογικό πρόβλημα με νομικές και κοινωνικές προεκτάσεις. Η διαδικασία της ψηφιοποίησης και η δημιουργία μιας νέας άυλης ηλεκτρονικής υπόστασης για τα έργα πολιτισμού, γεννά νέες δυνατότητες αλλά παράλληλα θέτει νέους περιορισμούς. Η έμπνευση και η δημιουργικότητα των καλλιτεχνών εκφράζεται με τα πνευματικά δικαιώματα, η προστασία και η διαχείριση των οποίων αποτελεί το αντικείμενο της διπλωματικής εργασίας. Το σύνολο των πνευματικών δικαιωμάτων και ο τρόπος που αυτά ορίζονται, δεσμεύονται, εγείρονται και μεταβιβάζονται, μεταβάλλεται ριζικά καθώς περνάμε από την πραγματική αναλογική μορφή στην άυλη ψηφιακή απεικόνιση. Στην παρούσα διπλωματική εργασία, ορίζονται οι διάφοροι τύποι δικαιωμάτων πνευματικής ιδιοκτησίας και αποσαφηνίζονται οι δεσμεύσεις και οι περιορισμοί που προκύπτουν από αυτά συναρτήσει της Διεθνούς,της Ευρωπαϊκής και της Ελληνικής Νομοθεσίας. Επίσης, καθορίζεται η ενδεικτική διαδικασία που πρέπει να ακολουθηθεί από μια οντότητα (πολύ συχνά από έναν πολιτιστικό οργανισμό) για την εκκαθάριση των δικαιωμάτων των έργων που κατέχει, κατά τη διαδικασία της Ψηφιοποίησης με σκοπό την προβολή τους στο Διαδίκτυο. Σε δεύτερη φάση, μελετάται το ευρύ φάσμα των τεχνολογικών μέσων, τα οποία μπορούν να χρησιμοποιηθούν για την προστασία των πνευματικών δικαιωμάτων που δεσμεύουν τους ψηφιακούς πόρους, παράλληλα με κάποιο κατάλληλα επιλεγμένο σύνολο μεταδεδομένων. Ιδιαίτερο τμήμα της εργασίας, αποτελούν τα συστήματα ψηφιακής διαχείρισης των πνευματικών δικαιωμάτων (DRMs). Πραγματοποιείται αναλυτική παρουσίαση των προτεινόμενων προτύπων που πρέπει να ακολουθούν τα συστήματα αυτά, όσον αφορά την αναπαράσταση και μοναδική αναγνώριση των δεδομένων, αλλά και την αναπαράσταση των δικαιωμάτων μέσων των γλωσσών περιγραφής πνευματικών δικαιωμάτων. Τέλος, παρουσιάζονται, η αρχιτεκτονική, οι βασικές λειτουργίες και η υλοποίηση ενός πρότυπου συστήματος διαχείρισης πνευματικών δικαιωμάτων για ψηφιακές εικόνες. / As Information Society is rapidly developing, technological conquests in computer science and telecommunications are becoming a very important part in many areas of social life, including Culture. The diversity of the cultural material and the intention of utilizing the added educational value, combined with the demand for preservation of the original works, compose a complex technological problem with legal and social extensions. The inspiration and creativity of the artists are expressed by Intellectual Property Rights – IPR, the protection and management of which is the subject of this thesis. The set of rights as well as the way they are specified, rised, binded and assigned changes while we pass from the analog to the materialess digital display. In this thesis we define the several types of Intellectual Property Rights and clarify the engagements and restrictions that result from them in connection with the International, European and National legislation. We also define the process that an entity (usually a cultural organization) must follow in order to clear the rights of the works it owns, during a digitization process which will lead to publication on the Internet. In the second part we study the technological solutions that can be used for the protection of IPR in parallel with a suitable metadata set. A special part of the thesis is the study of Digital Rights Management Systems – DRMs. We analytically present the standards on which modern DRMs must be based on in terms of identification and declaration of digital resources, as well as the representation of rights through rights expression languages. Finally we present the architecture, basic functionality and realization of a new Digital Rights Management System for digital images.

Made available in DSpace on 2014-12-17T14:55:18Z (GMT). No. of bitstreams: 1 ArrheniusVCO_da_capa_ate_pag_12.pdf: 7828798 bytes, checksum: b0f0c76e1aebc32a2155c024e0abc8a9 (MD5) Previous issue date: 2004-12-17 / The objective of the present work is develop a model to simulate electrical energy networks in transient and stead states, using the software ATP (Alternative Transient Program), able to be a way to join two distinct themes, present in classical methodology planning networks: short circuit analysis and load flow theory. Beyond that, using a tool for relay simulation, this paper intend to use the new developed model to investigate the influence of transient phenomenon in operation of protection relays, and calibrate the enterprise's protections relays. For testing the model, some relays, actually, installed at COSERN were used / O presente trabalho objetiva ao desenvolvimento de um modelo para simular redes de energia el?trica em regimes transit?rio e permanente, utilizando o software ATP (Alternative Transient Program), para servir como elo entre dois temas distintos, presentes na metodologia cl?ssica de planejamento de redes: a an?lise de curtos-circuitos e o estudo de fluxo de carga. Al?m disso, dispondo de uma ferramenta de simula??o de rel?s, pretende-se usar o novo modelo, tanto para averiguar a influ?ncia de fen?menos transit?rios na opera??o dos rel?s de prote??o, quanto para calibrar esses rel?s. Para testar o modelo, utilizaram-se alguns dos rel?s atualmente instalados na COSERN

No description available.

Les développements techniques entraînent une croissance exponentielle de la circulation des œuvres et informations sur les réseaux. Les modèles de régulation de l'ère analogique élaborés sur la rareté du support sont remis en question par le numérique, fondé sur les paradigmes de la copie, de la réappropriation et du partage. Le droit d'auteur a été développé et adapté au rythme des innovations techniques de reproduction et de diffusion des œuvres, comme un correctif artificiel accordant une exclusivité temporaire d'exploitation. Il peut aussi conduire aux biens communs. Nous analysons comment droit et technique ont d'abord été pensés de manière indépendante. Les processus d'élaboration des normes et standards techniques et l'extension des droits exclusifs entraînent des tensions entre les industries culturelles et le public. Cette conception conduit à un enchevêtrement de lois et mesures techniques de protection au profit de la régulation technique. Nous proposons donc, dans la lignée de la lex informatica, un modèle fondé sur l'influence réciproque entre les disciplines, vers la reconception des catégories juridiques du droit d'auteur et vers une meilleure expression technique des droits. Le développement d'applications, d'ontologies et de métadonnées juridiques permet une automatisation de la régulation des échanges d'œuvres et d'informations. Mettant en œuvre une intégration plus équilibrée du droit et de la technique, ce modèle est notamment fondé sur l'analyse de licences et modèles contractuels qui se développent sur Internet, entre contrôle d'accès et biens communs.