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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modeling of Kraft Mill Chemical Balance

Saturnino, Daniel M. 31 August 2012 (has links)
The reduction of mill effluent discharge as a result of stringent environmental legislations can have a significant impact on sodium (Na) and sulfur (S) balances in the kraft pulping process. In order to maintain a proper balance of Na and S, kraft mills may need to adopt different makeup strategies. For this purpose, a dynamic model was developed to predict the Na and S balance in the kraft recovery cycle, as well as the accumulation of undesirable non-process elements such as chlorine (Cl) and potassium (K). The model was developed using the CADSIM software and was validated using data obtained from a Brazilian bleached kraft pulp mill. The calculated data from the model showed good agreement with mill data with respect to all parts of the mill simulated. Dynamic tests designed to calculate the white liquor sulfidity over specific periods of time also presented good agreement. The result indicates that the model is able to describe the balance of chlorine, potassium, sodium and sulfur in the kraft process. A study conducted to evaluate the Cl and K accumulation agrees with the expected behaviour observed in mill data. The presence of ash treatment systems allow to reduce Cl and K contents in recovery boiler precipitator ash from 4.2 mol% Cl(Na+K) to 1.25 mol % and from 2.25 mol % K/(Na+K) to 0.8 mol% for 100% ash treated. The tests performed for Na and S balances focused in the makeup requirement for two situations: ash purging and ash treatment to control Cl and K levels. The use of ash treatment systems reduced Na and S makeup requirement from 5 to 50% depending on the amount of ash treated. A simple mathematical model was then used to estimate the Cl balances around the recovery cycle. Given that the proper simplifications are applied, the CADSIM model and the CSTR model presented good agreement in estimating the Cl balances. This result provided not only another method for the CADSIM model to be validated but also a way to calculate a rough estimate for Cl balance.
2

Modeling of Kraft Mill Chemical Balance

Saturnino, Daniel M. 31 August 2012 (has links)
The reduction of mill effluent discharge as a result of stringent environmental legislations can have a significant impact on sodium (Na) and sulfur (S) balances in the kraft pulping process. In order to maintain a proper balance of Na and S, kraft mills may need to adopt different makeup strategies. For this purpose, a dynamic model was developed to predict the Na and S balance in the kraft recovery cycle, as well as the accumulation of undesirable non-process elements such as chlorine (Cl) and potassium (K). The model was developed using the CADSIM software and was validated using data obtained from a Brazilian bleached kraft pulp mill. The calculated data from the model showed good agreement with mill data with respect to all parts of the mill simulated. Dynamic tests designed to calculate the white liquor sulfidity over specific periods of time also presented good agreement. The result indicates that the model is able to describe the balance of chlorine, potassium, sodium and sulfur in the kraft process. A study conducted to evaluate the Cl and K accumulation agrees with the expected behaviour observed in mill data. The presence of ash treatment systems allow to reduce Cl and K contents in recovery boiler precipitator ash from 4.2 mol% Cl(Na+K) to 1.25 mol % and from 2.25 mol % K/(Na+K) to 0.8 mol% for 100% ash treated. The tests performed for Na and S balances focused in the makeup requirement for two situations: ash purging and ash treatment to control Cl and K levels. The use of ash treatment systems reduced Na and S makeup requirement from 5 to 50% depending on the amount of ash treated. A simple mathematical model was then used to estimate the Cl balances around the recovery cycle. Given that the proper simplifications are applied, the CADSIM model and the CSTR model presented good agreement in estimating the Cl balances. This result provided not only another method for the CADSIM model to be validated but also a way to calculate a rough estimate for Cl balance.
3

Rekonstrukce objektu na penzion s restaurací / Reconstruction of the building to the boarding with restaurant

Halama, Stanislav January 2014 (has links)
The project is working on a complete documentation of Reconstruction of the building to the boarding with restaurant at the project specification for a building permit. Proposal places emphasis on building layout with a link to the site to ensure construction of static, fire safety, protection against noise, energy saving and safety in use. Drawings have been processed in software for design – Autocad.
4

Efeito da proteína p53 nas respostas celulares à terapia fotodinâmica com 1,9-dimetil azul de metileno / Effect of p53 protein on cell responses to photodynamic therapy with 1,9-dimethylmethylene blue

Abrantes, Aline Bianca de Paiva 07 April 2017 (has links)
A terapia fotodinâmica (TFD) é uma modalidade de tratamento que utiliza um fotossensibilizador, luz e oxigênio para gerar espécies reativas de oxigênio capazes de induzir a morte de células indesejadas, como tumores e micro-organismos infecciosos. Nosso foco está na morte induzida por 1,9-dimetil azul de metileno fotoativado (TFD-DMMB). Este fotossensibilizador foi previamente estudado por nosso grupo. Foi mostrado que o DMMB se acumula em lisossomos e mitocôndrias, e danifica essas organelas após fotoativado. O DMMB em concentração nanomolar promove uma morte celular eficiente, que parece ser resultante do bloqueio da conclusão do processo autofágico, enquanto outros fotossensibilizadores geralmente são empregados na faixa de micromolar. Nosso objetivo neste trabalho foi investigar o mecanismo molecular da TFD-DMMB através do estudo do papel da proteína p53 nas respostas celulares à TFD-DMMB. Sendo uma proteína supressora tumoral, p53 participa de vários processos celulares em resposta a diferentes estresses. Para atingir nosso objetivo, utilizamos linhagens celulares HEK293T que expressam diferentes quantidades de p53, sendo uma linhagem knockdown para p53 (HEK293T-p53KD) e outra com expressão normal de p53 (HEK293T-SC, scramble). Após o tratamento com DMMB fotoativado, avaliamos a fototoxicidade, apoptose, dano no DNA, ciclo celular e autofagia. Nossos resultados mostram que, apesar de não observarmos a estabilização de p53, a TFDDMMB parece induzir a localização citoplasmática de p53, sugerindo que p53 citoplasmática participa da resposta celular à TFD-DMMB. A linhagem HEK293T-p53KD mostrou-se menos sensível à TFD-DMMB. Essa diferença foi explicada pelo acúmulo de células em sub- G1, indicativo de morte por apoptose, apenas na linhagem HEK293T-SC, que foi mais sensível ao tratamento. É possível que a atividade citoplasmática de p53 esteja relacionada com a indução de apoptose no nosso modelo. Em contraste aos efeitos de p53 na morte celular, encontramos respostas à TFD-DMMB independentes de p53 na parada do ciclo celular e autofagia. Observamos acúmulo de células na fase S do ciclo celular associado à fosforilação de CHK1 e H2AX, indicativo da ocorrência de estresse replicativo. A relação com a autofagia foi confirmada pelo acúmulo de vesículas ácidas e aumento dos níveis proteicos de LC3-II. Esses resultados indicam a indução ou o bloqueio da autofagia, entretanto não observamos um aumento simultâneo nos níveis de BECLIN-1, proteína importante para a iniciação da autofagia. Além disso, DMMB fotoativado resultou em dano seletivo no DNA mitocondrial (mtDNA), que não foi reparado em 24 horas. Desse modo, e baseado nos resultados preliminares do nosso grupo, propomos que a morte celular induzida por DMMB fotoativado é decorrente principalmente do bloqueio da resolução da via autofágica, comprometendo a eliminação de mitocôndrias danificadas e levando a alterações na dinâmica do ciclo celular. Nossos resultados sugerem que há respostas celulares à TFDDMMB dependentes e independentes de p53. Resultados similares foram obtidos para a linhagem HEK293, que é a linhagem parental de HEK293T. Do nosso conhecimento, a relocalização de p53 para o citoplasma, a habilidade em induzir dano seletivo no mtDNA e o bloqueio da progressão do ciclo celular na fase S são resultados inéditos decorrentes da TFDDMMB. O dano seletivo ao mtDNA torna o DMMB um modelo útil para estudos de mecanismos de resposta a dano no DNA específicos para a mitocôndria. / Photodynamic Therapy (PDT) is a treatment modality that uses a photosensitizer, light and oxygen to generate reactive oxygen species capable of inducing death of unwanted cells, such as cancer cells and infectious microorganisms. In this work, we are interested in studying death induced by 1,9-dimethylmethylene blue as a photosensitizer by PDT (DMMB-PDT). This photosensitizer has been previously studied by our group. It has been shown that DMMB accumulates within lysosomes and mitochondria, and damages these organelles after photoactivation. In this case, cell death is believed to be a result from the impairment of autophagy. DMMB at nanomolar concentration promotes efficient cell death, while other photosensitizers are usually employed in the micromolar range. The aim of this work is to investigate the molecular mechanism of DMMB-PDT action through the study of p53 protein role over the cell response to DMMB-PDT. Being a tumor suppressor protein, p53 participates in several cellular processes in response to different stresses. To achieve our goal, we used HEK293T cell lines that express different amounts of p53: a p53 knockout cell line (HEK293T-p53KD) and a normal cell line (HEK293T-SC, scramble). After treatment with photoactivated DMMB, we evaluated phototoxicity, apoptosis, DNA damage, cell cycle, and autophagy. Our results showed that, although we did not observe p53 stabilization, DMMBPDT seems to induce the cytoplasmic localization of p53, suggesting that cytoplasmic p53 participates in the cell response to DMMB-PDT. The HEK293T-p53KD cell line was less sensitive to DMMB-PDT. This difference could be explained by the level of sub-G1 accumulation suggestive of apoptosis that was only observed for HEK293T-SC cell line, which was more sensitive to the treatment. It is possible that the cytoplasmic activity of p53 was related to apoptosis induction according our model. In contrast to p53 effects on cell death, we found that there are p53-independent responses to DMMB-PDT on cell cycle arrest and autophagy. We observed a significant increase in the fraction of cells in the S phase of the cell cycle associated with phosphorylation of the CHK1 and H2AX proteins, indicating induction of replicative stress. The relationship of DMMB-PDT and autophagy was confirmed by the accumulation of acidic vesicles and the increased LC3 conversion (LC3-I to LC3-II). These results indicated that DMMB-PDT induces and/or impairs autophagy. However, we did not observe a simultaneous increase in BECLIN-1 levels, which is an important protein to autophagy initiation. Photoactivated DMMB resulted in selective damage in mitochondrial DNA (mtDNA) that was not repaired in 24 hours. According to these results, we propose that cell death induced by photoactivated DMMB is mainly related to blockade of a late stage of the autophagy pathway. It could compromise the elimination of damaged mitochondria and might lead to cell cycle dynamics alterations. Our results suggested that there are p53-dependent and p53-independent cell responses to DMMB-PDT. Similar results were obtained from HEK293 cell line, which is the parental cell line of HEK293T. To the best of our knowledge, the p53 relocalization to the cytoplasm, the ability to induce selective mtDNA damage, and the S arrest represent new insights in the DMMB-PDT field. The selective mtDNA damage makes DMMB a useful model for studies on mechanisms of DNA damage responses in mitochondria.
5

A pol?tica de assist?ncia estudantil no contexto de expans?o do ensino superior: as particularidades do Programa de P?s-Gradua??o em Servi?o Social da UFRN

Silva, Maria L?cia da 27 December 2012 (has links)
Made available in DSpace on 2014-12-17T15:46:27Z (GMT). No. of bitstreams: 1 MariaLS_DISSERT.pdf: 3226194 bytes, checksum: 9dee30dde1674df8a94a8c2eb1a99501 (MD5) Previous issue date: 2012-12-27 / A disserta??o versa sobre a Pol?tica de Assist?ncia Estudantil e o processo de luta pela democratiza??o do acesso ? universidade, no contexto de expans?o do ensino superior em tempos de crise estrutural do capital. Apresenta como unidade de an?lise as particularidades da p?s-gradua??o em Servi?o Social da UFRN e tem como objetivo principal apreender e analisar as condi??es de perman?ncia disponibilizadas pela UFRN aos discentes de p?s-gradua??o no contexto de expans?o do Ensino Superior. O percurso te?rico-metodol?gico de an?lise adotado na pesquisa se fundamentou numa perspectiva cr?tica do objeto de estudo a partir de uma concep??o de totalidade, que pressup?e apreender as determina??es socioecon?micas e pol?ticas que incidem sobre a pol?tica de ensino superior e as condi??es de vida dos discentes do Programa de P?s-Gradua??o em Servi?o Social (PPGSS). As an?lises fundamentaram-se em pesquisa bibliogr?fica como base te?rico-metodol?gica da investiga??o, articulada com as reflex?es que resultaram dos dados emp?ricos da pesquisa de campo na perspectiva de apreens?o do objeto, em sua densidade hist?rica e num quadro de m?ltiplas determina??es. Do ponto de vista metodol?gico foram entrevistados 26 discentes e realizada an?lise documental referentes a leis e documentos da pol?tica educacional em n?vel federal e dos organismos internacionais. A luta por amplia??o do acesso ? universidade est? na agenda dos movimentos sociais no ?mbito da educa??o, no entanto na conjuntura dos governos de Luis In?cio Lula da Silva (2003 a 2010) e Dilma Rousseff (2011 a 2012) a tend?ncia tem sido seguir as orienta??es dos organismos internacionais e promover expans?o de vagas sem assegurar estrat?gias de perman?ncia compat?veis com as exig?ncias de excel?ncia acad?mica postas, por exemplo, na p?s-gradua??o. Discentes entrevistados acessam o ensino superior e os cursos de p?s-gradua??o e vivenciam dificuldades di?rias para atender com qualidade ?s exig?ncias acad?micas em face de suas condi??es materiais de vida e de trabalho e dos limites da pol?tica de assist?ncia estudantil que tem um perfil de programas e a??es localizadas
6

Efeito da proteína p53 nas respostas celulares à terapia fotodinâmica com 1,9-dimetil azul de metileno / Effect of p53 protein on cell responses to photodynamic therapy with 1,9-dimethylmethylene blue

Aline Bianca de Paiva Abrantes 07 April 2017 (has links)
A terapia fotodinâmica (TFD) é uma modalidade de tratamento que utiliza um fotossensibilizador, luz e oxigênio para gerar espécies reativas de oxigênio capazes de induzir a morte de células indesejadas, como tumores e micro-organismos infecciosos. Nosso foco está na morte induzida por 1,9-dimetil azul de metileno fotoativado (TFD-DMMB). Este fotossensibilizador foi previamente estudado por nosso grupo. Foi mostrado que o DMMB se acumula em lisossomos e mitocôndrias, e danifica essas organelas após fotoativado. O DMMB em concentração nanomolar promove uma morte celular eficiente, que parece ser resultante do bloqueio da conclusão do processo autofágico, enquanto outros fotossensibilizadores geralmente são empregados na faixa de micromolar. Nosso objetivo neste trabalho foi investigar o mecanismo molecular da TFD-DMMB através do estudo do papel da proteína p53 nas respostas celulares à TFD-DMMB. Sendo uma proteína supressora tumoral, p53 participa de vários processos celulares em resposta a diferentes estresses. Para atingir nosso objetivo, utilizamos linhagens celulares HEK293T que expressam diferentes quantidades de p53, sendo uma linhagem knockdown para p53 (HEK293T-p53KD) e outra com expressão normal de p53 (HEK293T-SC, scramble). Após o tratamento com DMMB fotoativado, avaliamos a fototoxicidade, apoptose, dano no DNA, ciclo celular e autofagia. Nossos resultados mostram que, apesar de não observarmos a estabilização de p53, a TFDDMMB parece induzir a localização citoplasmática de p53, sugerindo que p53 citoplasmática participa da resposta celular à TFD-DMMB. A linhagem HEK293T-p53KD mostrou-se menos sensível à TFD-DMMB. Essa diferença foi explicada pelo acúmulo de células em sub- G1, indicativo de morte por apoptose, apenas na linhagem HEK293T-SC, que foi mais sensível ao tratamento. É possível que a atividade citoplasmática de p53 esteja relacionada com a indução de apoptose no nosso modelo. Em contraste aos efeitos de p53 na morte celular, encontramos respostas à TFD-DMMB independentes de p53 na parada do ciclo celular e autofagia. Observamos acúmulo de células na fase S do ciclo celular associado à fosforilação de CHK1 e H2AX, indicativo da ocorrência de estresse replicativo. A relação com a autofagia foi confirmada pelo acúmulo de vesículas ácidas e aumento dos níveis proteicos de LC3-II. Esses resultados indicam a indução ou o bloqueio da autofagia, entretanto não observamos um aumento simultâneo nos níveis de BECLIN-1, proteína importante para a iniciação da autofagia. Além disso, DMMB fotoativado resultou em dano seletivo no DNA mitocondrial (mtDNA), que não foi reparado em 24 horas. Desse modo, e baseado nos resultados preliminares do nosso grupo, propomos que a morte celular induzida por DMMB fotoativado é decorrente principalmente do bloqueio da resolução da via autofágica, comprometendo a eliminação de mitocôndrias danificadas e levando a alterações na dinâmica do ciclo celular. Nossos resultados sugerem que há respostas celulares à TFDDMMB dependentes e independentes de p53. Resultados similares foram obtidos para a linhagem HEK293, que é a linhagem parental de HEK293T. Do nosso conhecimento, a relocalização de p53 para o citoplasma, a habilidade em induzir dano seletivo no mtDNA e o bloqueio da progressão do ciclo celular na fase S são resultados inéditos decorrentes da TFDDMMB. O dano seletivo ao mtDNA torna o DMMB um modelo útil para estudos de mecanismos de resposta a dano no DNA específicos para a mitocôndria. / Photodynamic Therapy (PDT) is a treatment modality that uses a photosensitizer, light and oxygen to generate reactive oxygen species capable of inducing death of unwanted cells, such as cancer cells and infectious microorganisms. In this work, we are interested in studying death induced by 1,9-dimethylmethylene blue as a photosensitizer by PDT (DMMB-PDT). This photosensitizer has been previously studied by our group. It has been shown that DMMB accumulates within lysosomes and mitochondria, and damages these organelles after photoactivation. In this case, cell death is believed to be a result from the impairment of autophagy. DMMB at nanomolar concentration promotes efficient cell death, while other photosensitizers are usually employed in the micromolar range. The aim of this work is to investigate the molecular mechanism of DMMB-PDT action through the study of p53 protein role over the cell response to DMMB-PDT. Being a tumor suppressor protein, p53 participates in several cellular processes in response to different stresses. To achieve our goal, we used HEK293T cell lines that express different amounts of p53: a p53 knockout cell line (HEK293T-p53KD) and a normal cell line (HEK293T-SC, scramble). After treatment with photoactivated DMMB, we evaluated phototoxicity, apoptosis, DNA damage, cell cycle, and autophagy. Our results showed that, although we did not observe p53 stabilization, DMMBPDT seems to induce the cytoplasmic localization of p53, suggesting that cytoplasmic p53 participates in the cell response to DMMB-PDT. The HEK293T-p53KD cell line was less sensitive to DMMB-PDT. This difference could be explained by the level of sub-G1 accumulation suggestive of apoptosis that was only observed for HEK293T-SC cell line, which was more sensitive to the treatment. It is possible that the cytoplasmic activity of p53 was related to apoptosis induction according our model. In contrast to p53 effects on cell death, we found that there are p53-independent responses to DMMB-PDT on cell cycle arrest and autophagy. We observed a significant increase in the fraction of cells in the S phase of the cell cycle associated with phosphorylation of the CHK1 and H2AX proteins, indicating induction of replicative stress. The relationship of DMMB-PDT and autophagy was confirmed by the accumulation of acidic vesicles and the increased LC3 conversion (LC3-I to LC3-II). These results indicated that DMMB-PDT induces and/or impairs autophagy. However, we did not observe a simultaneous increase in BECLIN-1 levels, which is an important protein to autophagy initiation. Photoactivated DMMB resulted in selective damage in mitochondrial DNA (mtDNA) that was not repaired in 24 hours. According to these results, we propose that cell death induced by photoactivated DMMB is mainly related to blockade of a late stage of the autophagy pathway. It could compromise the elimination of damaged mitochondria and might lead to cell cycle dynamics alterations. Our results suggested that there are p53-dependent and p53-independent cell responses to DMMB-PDT. Similar results were obtained from HEK293 cell line, which is the parental cell line of HEK293T. To the best of our knowledge, the p53 relocalization to the cytoplasm, the ability to induce selective mtDNA damage, and the S arrest represent new insights in the DMMB-PDT field. The selective mtDNA damage makes DMMB a useful model for studies on mechanisms of DNA damage responses in mitochondria.
7

Pricing of Power Derivatives / Pricing of Power Derivatives

Foukal, Viktor January 2014 (has links)
The main target of this thesis is to summarize and demonstrate the main characteristic of power markets and trying to find out electricity spot model. Thesis starts with definition of market subjects, typology of traded contracts and description of market development with focus on South Easter Europe. Thesis continues with development of consumption function and theoretical concepts of Demand/Capacity ratio which is used in short term/spot modeling and serve to identify a risk of potential increase in volatility. After deriving fundamental models I will continue with stochastic model - Volatility Regime model with Jump diffusion. I used all these knowledge and observed patterns in order to evaluate illiquid power options with daily settlement.
8

Ukončení účasti společníka ve společnosti s ručením omezeným / Termination of membership in limited liability company

Zanášková, Lucie January 2017 (has links)
Termination of membership in limited liability company Abstract The thesis deals with meanings of termination of membership in limited liability company, namely by (i) transfer of business interest, (ii), stepping out of the company, (iii) agreement on termination of shareholder's participation in a company, (iv) exclusion of a shareholder, (v) cancellation of shareholder's participation by court, (vi) termination of shareholder's participation due to insolvency proceedings against the shareholder, and (vii) termination of shareholder's participation due to execution towards the shareholder's interest. The thesis further deals with termination of shareholder's participation due to death of the shareholder who is a natural person or winding-up of the shareholder which is a legal entity. After a short foreword follow chapters concerning general issues about the limited liability company as a type of a legal corporation, the rights and obligations of shareholders and the creation and termination of participation in a limited liability company. Chapters dealing with various meanings of termination of shareholder's participation in a limited liability company and a brief conclusion follow. The aim of this thesis is to analyze and clarify some interpretative and application difficulties arising in connection with...
9

Je možné prostřednictvím vybraných investičních strategií generovat zisk na BCPP? / Is It Possible to Generate Profit Using Common Investment Strategies? The Case of Prague Stock Exchange

Charamza, Petr January 2009 (has links)
In this thesis we compared a profitability of several investment strategies that could be used at the stock markets and we adjusted them for the need of Prague Stock Exchange. The strategies that we used are based on some different principles and they provide different results. We found that the strategies based on the technical approach gave us better results than the strategies based on the fundamental approach. The next finding is that those strategies for which the investors would go also into the short sell perform better than the strategies for which the investors would take just the long positions. The best results we got for the momentum strategy, which is based on the autocorrelation of returns.
10

Legislativní prostředí obnovitelných zdrojů energie a jeho dopady na subjekty zapojené do tohoto odvětví / The legislative environment of the renewable resources and its impact on the subjects in this sector

PRŮKOVÁ, Veronika January 2013 (has links)
Within the literature review the diploma thesis deals with the definition of renewable resources, subjects of electricity market and the system of payments for the support of renewable energy. The aim of this diploma thesis is the analysis of the legislative environment before 2013 and in 2013. The practical part of my diploma thesis is focused on the development of energy legislation, relating to renewable resources in the Czech Republic but it also deals with foreign suggestions for energy legislation in this field. Considering the legislative change of the payments for the support of renewable energy, the reporting of electricity production resources and evidence of electricity production, which is based on the law 165/2012 legal code, the diploma thesis describes new information and data flows between subjects of electricity market and the way of payment for invoices for supported production of electricity as well. The diploma thesis characterizes the impact of legislative changes on the producers of electricity from the renewable resources. The diploma thesis is concerned with significantly discussed topics in the field of renewable resources. These topics are related to producers of electricity from the renewable resources and to consumers of electricity as well. The topics are especially about the amount of the payments for the support of solar energy and about establishment of the duty on solar energy. This diploma thesis can make the orientation in the legislative changes in 2013 for producers of electricity from the renewable resources easier. The diploma thesis can also help the electricity producers from the renewable resources in the necessary activities for the payment of supported production of electricity.

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