Esta pesquisa investigou as motivações econômicas que explicam o nível de reconhecimento dos tributos diferidos sobre o lucro nas companhias abertas brasileiras no período inicial de adoção das IFRS no Brasil e da vigência obrigatória do Regime Tributário de Transição. Foram selecionadas companhias abertas não financeiras brasileiras componentes no índice IBrX 100, sendo identificadas 68 companhias nos anos de 2010 à 2013 compreendendo assim 272 observações. A análise descritiva dos dados evidenciou que o montante dos passivos fiscais diferidos foi superior ao montante dos ativos fiscais diferidos em todos os anos pesquisados, situação esta que contrata com o cenário pré-IFRS onde existiam menos passivos fiscais diferidos devido às reduzidas opções de exclusões temporárias, e que os ativos fiscais diferidos são majoritariamente oriundos de diferenças temporárias, porém ocorrendo um crescimento maior dos créditos fiscais referentes a prejuízos fiscais no período combinado com uma evolução maior dos ativos fiscais totais do que dos passivos fiscais diferidos. Por meio da análise multivariada de regressão múltipla com dados em painel foi possível constatar que: (i) não há relacionamento significativo entre o reconhecimento de tributos diferidos e o endividamento da empresa, isto é, não existe evidência que as companhias utilizem os tributos diferidos com a finalidade de influenciar o nível de endividamento, apesar da possibilidade de quebra de covenants e, consequentemente, aumento de seu risco de crédito, (ii) as maiores empresas tendem a registrar um valor menor de ativos fiscais diferidos líquidos de forma a reduzir seus lucros e divulgar sua sobretaxação a fim de reduzir sua exposição pública, e (iii) as empresas menos lucrativas são propensas a reconhecer um montante maior de ativos fiscais diferidos líquidos para, presumivelmente, atenuar o baixo resultado da empresa e com isso mascarar o seu fraco desempenho, e também, por outro lado, as companhias que possuem maior rentabilidade tendem a registrar valores menores de ativos fiscais diferidos líquidos no sentido de reduzir o lucro, e com isso, diminuir seus custos políticos. Assim, os resultados obtidos sugerem que as empresas utilizam a discricionariedade proporcionada pela regulação contábil dos tributos diferidos para atingir seus objetivos e demandas, no sentido de reduzir sua exposição pública e melhorar sua rentabilidade. / This research investigated the economic motivations that explain the level of recognition of deferred income taxes in the Brazilian companies during initial adoption of IFRS in Brazil and the mandatory term of the Transitional Tax Regime. Non-financial public companies were selected in the index IBrX 100, 68 companies were identified from 2010 to 2013 comprising 272 observations. The descriptive analysis of the data indicated that the amount of deferred tax liabilities was greater than the amount of deferred tax assets in all years studied, a situation that contracts with the pre-IFRS scenario where there were fewer deferred tax liabilities due to reduced options of temporary exclusions and that the deferred tax assets are mainly arising from temporary differences, however there was further growth of tax credits related to tax losses in the period combined with a greater increase in total tax assets than deferred tax liabilities. In the multivariate multiple regression analysis with panel data it was found that: (i) there is no significant relationship between the recognition of deferred taxes and the debts of the Company, that is, there is no evidence that companies use deferred taxes for the purpose of influencing the level of debt, despite the possibility of covenants be broken and, consequently, increase its credit risk, (ii) larger firms tend to register a lower value of net deferred tax assets to reduce their profits and disclose their overcharge in order to reduce public exposure, and (iii) the least profitable firms are likely to recognize a greater amount of net deferred tax assets for presumably mitigate the low result of the company and thus mask their poor performance and also, on the other hand, companies that have higher profitability tend to register lower values of net deferred tax assets to reduce profit, and thus, lower their political costs. Thus, the results suggest that companies use discretion provided by the accounting regulation of deferred taxes to achieve their goals and demands, to reduce public exposure and improve its profitability.

Esta pesquisa investigou as motivações econômicas que explicam o nível de reconhecimento dos tributos diferidos sobre o lucro nas companhias abertas brasileiras no período inicial de adoção das IFRS no Brasil e da vigência obrigatória do Regime Tributário de Transição. Foram selecionadas companhias abertas não financeiras brasileiras componentes no índice IBrX 100, sendo identificadas 68 companhias nos anos de 2010 à 2013 compreendendo assim 272 observações. A análise descritiva dos dados evidenciou que o montante dos passivos fiscais diferidos foi superior ao montante dos ativos fiscais diferidos em todos os anos pesquisados, situação esta que contrata com o cenário pré-IFRS onde existiam menos passivos fiscais diferidos devido às reduzidas opções de exclusões temporárias, e que os ativos fiscais diferidos são majoritariamente oriundos de diferenças temporárias, porém ocorrendo um crescimento maior dos créditos fiscais referentes a prejuízos fiscais no período combinado com uma evolução maior dos ativos fiscais totais do que dos passivos fiscais diferidos. Por meio da análise multivariada de regressão múltipla com dados em painel foi possível constatar que: (i) não há relacionamento significativo entre o reconhecimento de tributos diferidos e o endividamento da empresa, isto é, não existe evidência que as companhias utilizem os tributos diferidos com a finalidade de influenciar o nível de endividamento, apesar da possibilidade de quebra de covenants e, consequentemente, aumento de seu risco de crédito, (ii) as maiores empresas tendem a registrar um valor menor de ativos fiscais diferidos líquidos de forma a reduzir seus lucros e divulgar sua sobretaxação a fim de reduzir sua exposição pública, e (iii) as empresas menos lucrativas são propensas a reconhecer um montante maior de ativos fiscais diferidos líquidos para, presumivelmente, atenuar o baixo resultado da empresa e com isso mascarar o seu fraco desempenho, e também, por outro lado, as companhias que possuem maior rentabilidade tendem a registrar valores menores de ativos fiscais diferidos líquidos no sentido de reduzir o lucro, e com isso, diminuir seus custos políticos. Assim, os resultados obtidos sugerem que as empresas utilizam a discricionariedade proporcionada pela regulação contábil dos tributos diferidos para atingir seus objetivos e demandas, no sentido de reduzir sua exposição pública e melhorar sua rentabilidade. / This research investigated the economic motivations that explain the level of recognition of deferred income taxes in the Brazilian companies during initial adoption of IFRS in Brazil and the mandatory term of the Transitional Tax Regime. Non-financial public companies were selected in the index IBrX 100, 68 companies were identified from 2010 to 2013 comprising 272 observations. The descriptive analysis of the data indicated that the amount of deferred tax liabilities was greater than the amount of deferred tax assets in all years studied, a situation that contracts with the pre-IFRS scenario where there were fewer deferred tax liabilities due to reduced options of temporary exclusions and that the deferred tax assets are mainly arising from temporary differences, however there was further growth of tax credits related to tax losses in the period combined with a greater increase in total tax assets than deferred tax liabilities. In the multivariate multiple regression analysis with panel data it was found that: (i) there is no significant relationship between the recognition of deferred taxes and the debts of the Company, that is, there is no evidence that companies use deferred taxes for the purpose of influencing the level of debt, despite the possibility of covenants be broken and, consequently, increase its credit risk, (ii) larger firms tend to register a lower value of net deferred tax assets to reduce their profits and disclose their overcharge in order to reduce public exposure, and (iii) the least profitable firms are likely to recognize a greater amount of net deferred tax assets for presumably mitigate the low result of the company and thus mask their poor performance and also, on the other hand, companies that have higher profitability tend to register lower values of net deferred tax assets to reduce profit, and thus, lower their political costs. Thus, the results suggest that companies use discretion provided by the accounting regulation of deferred taxes to achieve their goals and demands, to reduce public exposure and improve its profitability.

This master thesis deals with methods of stations’ geolocation on the Internet, it means the estimation geographic location of unknown station, which is conected to this network. The introductory part describes the methods for determining position, which don‘t need any measeruments of the network. The next section is devoted to points, where delay is invoked, to the causes of latency in the Internet, to their types and some usual values. The following part features ways to measure delays and route, including several tools for this purpose. The penulminate section describes some chosen geolocation techniques based on RTT measurement. The final chapter is devoted to practical demonstration geolocation using the CBG method, when the delay measurement was carried out in an experimental PlanetLab network.

This paper deals with methods of stations’ IP geolocation. It’s describes the methods of passive and active geolocation and it’s more focused on active searching methods, which usees measuring the latency in network. The factors causing delays in data transfer are discussed first, followed by discussion of the issue of measuring these delays. After that a brief description of PlanetLab experimental network, which nodes were used for delay measurment. Main topic is practical implementation of method Constraint-based Geolocation in Java programming language. Last but not least the measurement results of CBG algorithm are tested.

Due to rapid increasing in complexity of Internet, quantifying the performance of protocol helps in assessing the application behavior with respect to network performance. TCP is an important protocol that is used by some important applications on Internet such as HTTP, FTP and soon. To analyze TCP, Round trip times is one of the metric used. As it is a internal metric of TCP used to find the retransmission timeout of sent packet. Round trip times means measuring elapsed time between the sent packet and recieving its acknowledgment that covers the sequence number of the sent packet(i.e., from source to destination and vice-a-versa). Round trip times is a metric that is recognised by IETF as Quality of Service parameter. We design a tool here that will calculate the round trip times for each stream. This round trip times helps us to understand the protocol behavior. In this document, we discuss the design, implementation issues carried out while developing the tool. This tool is capable of reading offline as well as online streams and helps us to analyze the statistics obtained from collected round trip times of each stream. / 91-40-24023214

¡@¡@In this Thesis, we proposed a new SVC Layer Scheduling Algorithm (CSDB, Chunk Scheduling with Delay-trend and Bandwidth-monitoring) in SVC-P2P Video Streaming by using RTT Probing and Bandwidth Monitoring mechanisms to measure RTT/2 and historic bandwidth between peers simultaneously. When transmission delay (TD) dominates in the end-to-end delay and when instantaneous bandwidth increases, peer will quickly increase the downloading layers of video segment (VS). On the other hand, when instantaneous bandwidth decreases, peer will decrease the number of layer chunks (LCs) not in time according to RTT/2 and historic bandwidth. When queuing delay (QD) and propagation delay (PD) dominate in the end-to-end delay, peer will assume RTT/2 is accurate because every LC is in time. In this case, peer will quickly increase the downloading layers; otherwise, peer assumes there is a big difference between RTT/2 and one-way delay (OWD) such that it will decrease the downloading layers to half. When peer cannot grab VS in time according to measured RTT/2 but every LC grabbed is in time, peer will assume there is a big difference between measured RTT/2 and OWD. In this case, peer will keep no change in downloading layers; otherwise, peer will assume measured RTT/2 is close to OWD, and it will decrease the downloading layers to half. ¡@¡@In order to demonstrate the advantages of CSDB, we designed a simulator written in C++. In the simulation, we consider two scenarios: 1) When TD dominates. 2) When QD and PD dominate. Simulation results show that peer can achieve high quality SVC video by balancing the number of received layers and the number of LCs not it time.

In an LTE (Long-Term Evolution) network, HARQ (Hybrid Automatic Repeat reQuest) is used to reduce the error probability of retransmitted packets. However, HARQ cannot guarantee delay constraints for real-time traffic when RBs (Resource Blocks) are allocated improperly. To avoid the retransmitted real-time packets exceeding their delay constraints, we propose an HARQ scheduling scheme based on RTT (Round-Trip-Time) estimation. In this scheme, traffic are classified into real-time and non-real-time queues in which real-time queue are further classified into four sub-queues according to their retransmission times; i.e., the first transmission queue, the first retransmission queue, the second retransmission queue, and the third retransmission queue. For the four real-time queues, we estimate RTT and compute the number of RBs required satisfying the delay constraints. To prevent from starvation of non-real-time traffic, after allocating the RBs for real-time traffic, the remaining RBs are allocated for non-real-time traffic according to their MBR (Minimum Bit Rate). To analyze the proposed scheduling scheme, we build a mathematical model to derive the successful probability of retransmitted packets and the expected value of packet retransmission times. Finally, we compute average packet delay, average packet loss rate, and the throughput for both real-time and none-real-time traffic by varying packet error probability and the delay constraints of real-time traffic.

Submitted by Pós Imunologia (ppgimicsufba@gmail.com) on 2017-02-14T15:24:05Z No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2017-06-29T13:56:29Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / Made available in DSpace on 2017-06-29T13:56:29Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / CAPES / Com o aumento da prevalência de doenças inflamatórias, em especial as alérgicas, a busca por estratégias terapêuticas visando à melhoria de vida dos indivíduos doentes tornou-se um vasto campo de pesquisa. Neste âmbito, o uso de helmintos e derivados que possuem potencial imunomodulatório tem se mostrado eficiente na inibição da inflamação em modelos experimentais dessas doenças. Objetivo: Produzir e analisar, in silico, o antígeno recombinante do Trichuris trichiura homólogo ao fator inibidor de migração de macrófagos (rTt-MIF) e avaliar seu efeito em cultura de células monomorfonucleares de sangue periférico (CMSP) de indivíduos atópicos e não atópicos. Métodos: A análise in silico da proteína foi realizada utilizando diversas ferramentas de bioinformática. A sequência codificadora do antígeno recombinante foi sintetizada e clonada em um plasmídeo de expressão, a partir do qual foi realizada a expressão heteróloga da proteína em sistema procarioto, com posterior purificação por cromatografia de afinidade e determinação do conteúdo proteico e de endotoxina. Após teste cutâneo e dosagem de IgE por ImunoCAP, foram selecionados 12 indivíduos não atópicos e 14 indivíduos atópicos cujo sangue periférico foi coletado para realizar o cultivo de células monomorfonucleares. As células foram cultivadas sob três condições: estímulo do rTt-MIF, meio de cultivo sem estímulo e estimuladas por Pokeweed ou LPS. Após o cultivo, os sobrenadantes foram coletados para realização da dosagem das citocinas IL-10, IFN-γ, IL-5 e IL-17A. Resultados: A molécula caracterizada como estável e solúvel foi produzida, obtida na quantidade de 2,4 mg/mL com 1,9 EU/mL. O rTt-MIF induziu o aumento da produção de IL-10 pelas células dos indivíduos atópicos (P=0,0001) e dos não atópicos (P=0,0005). Em relação às citocinas IFN-γ, IL-5 e IL-17, o rTt-MIF não induziu a produção destas pelas células dos indivíduos atópicos e não atópicos. Conclusão: A ação do rTt-MIF sobre o cultivo de células momonucleares do sangue periférico, de aumentar a produção de IL-10 e não induzir a produção de IFN-γ, IL-5 e IL-17A, mostra o potencial imunomodulador dessa molécula, com possível efeito de reduzir a elevação de eosinófilos, neutrófilos e citocinas inflamatórias. / With the increasing prevalence of inflammatory diseases, in particular allergies, the search for therapeutic strategies aiming to improve life quality of sick individuals has become a vast field of research. In this context, the use of helminths and their derivatives that demonstrate potential immunomodulatory effect has been effective in inhibiting inflammation in experimental models of inflammatory diseases. Objective: To produce and analyze in silico the recombinant antigen from Trichuris trichiura homologous to the macrophage migration inhibitory factor (rTt-MIF) and evaluate its effect on peripheral blood mononuclear cells culture (PBMC) of atopic and non-atopic individuals. Methods: Bioinformatics tools made the analysis in silico. The Tt-MIF codifying sequence was synthesized and cloned into a plasmid, allowing the heterologous expression of the protein in a prokaryotic system, with subsequent purification by affinity chromatography and protein and endotoxin quantifications. After prick test and IgE dosage by ImmunoCAP test, 12 non-atopic individuals and 14 atopic individuals were selected, whose peripheral blood were collected to obtain the mononuclear cells (PBMC) for in vitro culture. Cells were stimulated with the rTt-MIF, as negative control cells were cultivated without stimuli and, as positive control, cells were cultivated with Pokeweed or LPS. After the culture, the supernatants were assayed to quantify IL-10, IFN-γ, IL-5 and IL-17A. Results: The protein characterized as soluble and stable was produced and obtained in the amount of 2,4 mg/mL with 1,9 EU/mL. The rTt-MIF induced a stimulatory effect on IL-10 production by cells from atopic individuals (P=0.0001) and by cells from non-atopic individuals (P=0,0005). The rTt-MIF did not induce the production of IFN-γ, IL-5 and IL-17A by cells from atopic and non-atopic individuals. Conclusion: The effects of rTt-MIF increasing IL-10 production and not inducing the production of IFN-γ, IL-5 and IL-17A on human PBMC cultures are indicative of its immunomodulatory potential, with possible effect of decreasing eosinophilic and neutrophilic presence and inducing immune regulation.

No description available.

Dissertation thesis deals with methods for finding the location of the device in the Internet, based on knowledge of the IP address. The process is called IP geolocation and is currently solved by geolocation databases or by measurement of network properties to the IP address. The disadvantage of nowadays geolocation databases is an incorrect information about some locations, because they can be in large distance from correct position. The aim of the thesis is to develop a method for verification of a position from geolocation database using delay measurement. Because of it, there is a detail analysis of influence of partial delays on the distance estimation accuracy, calculated using measured delay between the landmark and the target IP address. For the same reason, long-term delay measurement was performed, where the IP geolocation accuracy was compared using calibration data from previous measurements. On this background, Cable Length Based Geolocalisation (CLBG) method is proposed. Principle of this method is built on the properties of partial delays, which depend on the length of transport media. Firstly, the method measures round trip time (rtt), which is subsequently lowered by intermediate devices and end stations delay. The geographical distance is estimated using signal speed in the transport media. Further, the winding media parameter is established, which is used to determine a constraint around the landmark. The intersection of all constraints defines the area, where the target IP is. The IP geolocation using CLBG gives better results than simpler methods (ShortestPing, GeoPing and SOI), in comparison with more advanced methods (CBG and Octant) the accuracy is similar. The disadvantage of the CLBG method is the size of region, where the target lies, but this is due to its purpose. The position found in geolocation database can be checked by evaluation if it lies in the region.