This thesis deals with the introduction to the security mechanism.The procedure explains the basic concepts, principles of cryptography and security of modern protocols and basic principles that are used for information transmission network. The work also describes the most common types of attacks targeting the eavesdropping of communication. The result is a design of the eavesdropping and the implementation of an attack on the secure communication of the SSL protocol..The attacker uses a false certificate and attacks based on poisoning the ARP and DNS tables for this purpose. The thesis discusses the principles of the SSL protocol and methodology of attacks on the ARP and DNS tables.

A alveolite é uma complicação pós-operatória de carácter inflamatório que acomete alvéolos de dentes recém-extraídos. A incidência dessa complicação varia de 1 a 4% e pode chegar a 30%. O objetivo deste estudo foi analisar os mecanismos biológicos envolvidos no processo de reparo de alvéolos intencionalmente infectados, em ratos; comparar diferentes modalidades de tratamento e correlacionar os resultados encontrados através de duas análises (microscópica e molecular). Foram utilizados 84 ratos, divididos nos grupos: I: alvéolo não infectado; II: alvéolo infectado sem nenhum tratamento; III: alvéolo infectado tratado com irrigação de solução de iodeto de sódio a 2% e peróxido de hidrogênio a 3% na proporção de 1:1; e IV: alvéolo infectado submetido à curetagem, irrigação com soro fisiológico e preenchimento com uma pasta à base de metronidazol. Os animais foram eutanasiados aos 6, 15 e 28 dias pós-operatório. Foi realizada a análise quantitativa da expressão de genes envolvidos no processo de reparo [colágeno tipo I (COL-I), fator de crescimento do endotélio vascular (VEGF), osteocalcina (OCN), fosfatase alcalina (ALP), runt-related transcription factor 2 (RUNX2) e fator de necrose tumoral alfa (TNF-\'alfa\')], através da RealTimePCR, correlacionando sua expressão com as características microscópicas observadas qualitativa e quantitativamente. Com base nos resultados da análise microscópica e molecular, podemos concluir que os marcadores RUNX2, OCN e TNF-\'alfa\' podem ser usados como indicadores para avaliar a neoformação óssea e a quantidade de infiltrado inflamatório em alveolite. Os marcadores ALP e VEGF não representaram adequadamente o que se observou microscopicamente. Embora o tratamento da alveolite com a pasta à base de metronidazol promova maior densidade de neoformação óssea aos 28 dias, não há diferenças entre os tratamentos. / Dry socket is an inflammatory postoperative complication that undertakes sockets of recently extracted teeth. The incidence of such complication varies from 1 to 4% and might reach up to 30%. The objective of this study was to analyze the biological mechanisms involved in the repair process of intentionally infected sockets in mice; compare different treatment conditions and correlate the results of two different analysis (microscopic and molecular). 84 mice were used in this study, divided according the following groups: I: uninfected socket; II: infected socket without any treatment; III: infected socket treated with irrigation of 2% sodium iodide and 3% hydrogen peroxide solution at 1:1 proportion; and IV: infected socket submitted to curettage, physiological saline solution irrigation and fulfillment with metronidazole base paste. The animals were killed at a postoperative period of 6, 15 and 28 days. A quantitative analysis was performed using a RealTimePCR to evaluate the genes expression involved [Collagen Type I (COL-I), vascular endothelial growth factor (VEGF), osteocalcin (OCN), alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2) and tumor necrosis factor-alpha (TNF-\'alpha\')], in the repair process, correlating its expression with the microscopic characteristics observed in both qualitative and quantitative manner. Based in the results of the microscopic and molecular analysis, it can be concluded that the RUNX2, OCN and TNF-\'alpha\' markers can be used as indicators to evaluate the dry socket bone neoformation and inflammatory infiltrate quantity. The ALP and VEGF markers did not represented appropriately what was observed microscopically. Although the dry socket treatment with metronidazole base paste promotes an increase in the bone neoformation density at 28 days, no difference was found among the treatments.

RealTest is a company located in V¨aster˚as, Sweden, that works with embedded systems and test systems. RealTest had a need for a new test system for one of their products, the MiniTester (MT) mk2 that is used to test Drive Control Units (DCUs) used on trains. The problems that had to be solved were, finding out the most common faults of the product, make the test system modifiable and scalable, have a software running on a Windows PC with a working GUI and test logic and design a hardware component measurement unit to generate and measure signals. The system described in this report is the software parts of the developed MiniTest tester that runs on a Windows PC as well as the hardware design. The programming of the measurement unit and the testing of that unit is not covered by this report. The hardware consist of custom PCBs and Arduino boards. The Windows PC programs implemented a GUI and test logic according to the goals with a few exceptions left for further work. These programs have been evaluated by emulating the hardware. The system is shown to be modifiable in practice by implementation and scalable in theory

A alveolite é uma complicação pós-operatória de carácter inflamatório que acomete alvéolos de dentes recém-extraídos. A incidência dessa complicação varia de 1 a 4% e pode chegar a 30%. O objetivo deste estudo foi analisar os mecanismos biológicos envolvidos no processo de reparo de alvéolos intencionalmente infectados, em ratos; comparar diferentes modalidades de tratamento e correlacionar os resultados encontrados através de duas análises (microscópica e molecular). Foram utilizados 84 ratos, divididos nos grupos: I: alvéolo não infectado; II: alvéolo infectado sem nenhum tratamento; III: alvéolo infectado tratado com irrigação de solução de iodeto de sódio a 2% e peróxido de hidrogênio a 3% na proporção de 1:1; e IV: alvéolo infectado submetido à curetagem, irrigação com soro fisiológico e preenchimento com uma pasta à base de metronidazol. Os animais foram eutanasiados aos 6, 15 e 28 dias pós-operatório. Foi realizada a análise quantitativa da expressão de genes envolvidos no processo de reparo [colágeno tipo I (COL-I), fator de crescimento do endotélio vascular (VEGF), osteocalcina (OCN), fosfatase alcalina (ALP), runt-related transcription factor 2 (RUNX2) e fator de necrose tumoral alfa (TNF-\'alfa\')], através da RealTimePCR, correlacionando sua expressão com as características microscópicas observadas qualitativa e quantitativamente. Com base nos resultados da análise microscópica e molecular, podemos concluir que os marcadores RUNX2, OCN e TNF-\'alfa\' podem ser usados como indicadores para avaliar a neoformação óssea e a quantidade de infiltrado inflamatório em alveolite. Os marcadores ALP e VEGF não representaram adequadamente o que se observou microscopicamente. Embora o tratamento da alveolite com a pasta à base de metronidazol promova maior densidade de neoformação óssea aos 28 dias, não há diferenças entre os tratamentos. / Dry socket is an inflammatory postoperative complication that undertakes sockets of recently extracted teeth. The incidence of such complication varies from 1 to 4% and might reach up to 30%. The objective of this study was to analyze the biological mechanisms involved in the repair process of intentionally infected sockets in mice; compare different treatment conditions and correlate the results of two different analysis (microscopic and molecular). 84 mice were used in this study, divided according the following groups: I: uninfected socket; II: infected socket without any treatment; III: infected socket treated with irrigation of 2% sodium iodide and 3% hydrogen peroxide solution at 1:1 proportion; and IV: infected socket submitted to curettage, physiological saline solution irrigation and fulfillment with metronidazole base paste. The animals were killed at a postoperative period of 6, 15 and 28 days. A quantitative analysis was performed using a RealTimePCR to evaluate the genes expression involved [Collagen Type I (COL-I), vascular endothelial growth factor (VEGF), osteocalcin (OCN), alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2) and tumor necrosis factor-alpha (TNF-\'alpha\')], in the repair process, correlating its expression with the microscopic characteristics observed in both qualitative and quantitative manner. Based in the results of the microscopic and molecular analysis, it can be concluded that the RUNX2, OCN and TNF-\'alpha\' markers can be used as indicators to evaluate the dry socket bone neoformation and inflammatory infiltrate quantity. The ALP and VEGF markers did not represented appropriately what was observed microscopically. Although the dry socket treatment with metronidazole base paste promotes an increase in the bone neoformation density at 28 days, no difference was found among the treatments.

Protein sequences contain the information in order for a protein to fold to a unique compact, three-dimensional native structure. The forces that drive protein structures to form compact folds are largely dominated by burial of hydrophobic amino acids, which results in non-specific packing of amino acid side-chains. The knob-socket model attempts to organize side-chain packing into tetrahedral packing motifs. This tetrahedral motif is characterized with a three residues on the same secondary structure forming the base of the tetrahedron packing with a side-chain from a separate secondary structure. The base of the motif is termed the socket, and the other side-chain is called the knob. Here, we focus on extending the knob-socket model to understand tertiary and quaternary structure. First, single knobs sometimes pack into more than one socket in real structures. We focus on understanding the topology and amino acid preferences of these tertiary packing surfaces. The main results from the study of tertiary packing surfaces is that they have a preferred handedness, some interactions are ancillary to the packing interaction, there are specific amino preferences for specific positions in packing surfaces, and there is no relationship between side-chain rotamer of the knob packing into the tertiary packing surface. Next, we examine the application of the knob-socket to irregular and mixed packing in protein structure. The main conclusions from these efforts show canonical packing modes between secondary structures and highlight the important of coil secondary structure in providing many of the knobs for packing. Third, we investigate protein quaternary structure with a clique analysis of side-chain interactions. We identify a possible pseudo knob-socket interaction, and compare knob-socket interactions between tertiary and quaternary structure. Lastly, we discuss the workflow used in CASP12 to predict side-chain contacts and atomic coordinates of proteins.

Proteins are molecular machines of life in the truest sense. Being the expressors of genotype, proteins have been a focus in structural biology. Since the first characterization and structure determination of protein molecule more than half a century ago1, our understanding of protein structure is improving only incrementally. While computational analysis and experimental techniques have helped scientist view the structural features of proteins, our concepts about protein folding remain at the level of simple hydrophobic interactions packing side-chain at the core of the protein. Furthermore, because the rate of genome sequencing is far more rapid than protein structure characterization, much more needs to be achieved in the field of structural biology. As a step in this direction, my dissertation research uses computational analysis and experimental techniques to elucidate the fine structural features of the tertiary packing in proteins. With these set of studies, the knowledge of the field of structural biology extends to the fine details of higher order protein structure.