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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.
71

Marcado para morrer: moralidades e socialidades das crianÃas na comunidade do Serviluz (Fortaleza-CE) / Marked to die: moralities and socialties of children in the community of Serviluz (Fortaleza-CE)

Deiziane Pinheiro Aguiar 15 March 2017 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O objetivo dessa dissertaÃÃo à descrever e analisar como a situaÃÃo e a condiÃÃo de indivÃduos âmarcados para morrerâ (ameaÃados de morte) afeta as socialidades das crianÃas moradoras do Serviluz, tendo em vista que, muitas delas perderam seus parentes em decorrÃncia da violÃncia letal na favela. A interface com a antropologia da crianÃa, a sociologia da infÃncia, alÃm da sociologia e antropologia da moral conduzem essa investigaÃÃo. A problemÃtica teÃrica central ou a generalidade teÃrica do objeto de pesquisa concentra-se no que estou chamando de sujeitos indesejÃveis. Jovens sÃo ameaÃados de morte nas favelas e periferias, moralmente condenados, rechaÃados da sua rede de relaÃÃes sociais e informados (estigmatizados e condenados) como sujeitos matÃveis ou como vidas descartÃveis. A articulaÃÃo dessa investigaÃÃo socioantropolÃgica se dà pela perspectiva da agÃncia das crianÃas, das moralidades e das percepÃÃes que elas possuem sobre os sujeitos indesejÃveis. AlÃm disso, o âmarcado para morrerâ à compreendido aqui como um dispositivo moral extremamente relevante para as socialidades e a construÃÃo moral das crianÃas do Serviluz. O trabalho de campo etnogrÃfico à a base desta pesquisa, a partir de conversas informais com crianÃas e adultos, conversaÃÃes gravadas, roda de conversaÃÃo e brincadeiras com as crianÃas. AtravÃs disso foi possÃvel construir as interaÃÃes em campo e a produÃÃo de dados empÃricos.
72

Toxicidade do sulfato de cobre para a tilápia, Oreochromis niloticus e teste ecotoxicológico com Ceriodaphnia dúbia e Pseudokirchneriella subcapitata /

Carvalho, Solange de. January 2009 (has links)
Resumo: O objetivo deste estudo foi avaliar o efeito sub-letal do sulfato de cobre para a tilápia, na concentração de 0,5 e 2,0 mg.L-1 durante exposição e recuperação e determinar a toxicidade aguda para Ceriodaphnia dubia e para a alga Pseudokirchneriella subcapitata. Foram realizados dois ensaios (ensaios I e II) utilizando jovens de tilápia com peso médio de 38,29 g. Determinou-se neste estudo as concentrações de cobre nas brânquias, fígado e músculo dos animais, foram feitas também análises hematológicas, imunológicas, bioquímicas e histopatológicas durante exposição ao sulfato de cobre e posterior recuperação. Para o teste de toxicidade com C. dubia e P. subcapitata foram utilizadas as mesmas concentrações de sulfato de cobre do ensaio com peixes. Os cladóceros e as algas foram expostos a diluições dessas concentrações durante sete e três dias, respectivamente. Para a C. dubia observou-se a mortalidade e o efeito sobre a reprodução dos mesmos. Já para as algas foi observado o efeito inibitório sobre a taxa de crescimento. A exposição ao cobre no ensaio I e II resultou em acúmulo significativo de cobre nos tecidos analisados, com exceção do músculo. E no período de recuperação os valores de cobre permaneceram altos. O sulfato de cobre não provocou alterações hematológicas. Por outro lado, causou diminuição da capacidade fagocítica dos macrófagos de peixes expostos à concentração de 2,0mg.L-1 de CuSO4 no ensaio I. O cobre também causou diminuição da concentração de GSH. Com relação às análises histopatológicas houve alteração nas brânquias e hepatopâncreas em ambos os ensaios. Os resultados do teste ecotoxicológico com C. dubia P. subcapitata mostrou que o sulfato de cobre causou toxicidade aguda para estes organismos. O uso desse produto na aqüicultura pode comprometer o cultivo, uma vez que ocorreram danos a saúde dos peixes ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The copper sulphate is one of the most widely used chemicals for the control of parasites and for the control of phytoplankton in aquaculture. The purpose of this study was to evaluate sublethal effects of concentrations of copper sulphate on tilapia. In addition, ecotoxicity of this compound was determinate for microcrustaceans Ceriodaphnia dubia and the alga Pseudokirchneriella subcapitata. The biomarkers evaluated in this study were copper bioaccumulation in tissues, hematological, immunological, biochemical and histopathological parameters. The copper toxicity for microcrustacean C. dubia, was evaluated with acute tests through mortality. The exposure to copper in the experiments I and II resulted in significant accumulation of copper in the tissues, except for the muscle. In the recovery period, the copper values of remained high in all tissues. The haematological parameters were not affected by the copper sulphate. However, was observed in experiment I a significant change in the phagocytic capacity of macrophages in fish exposed to concentration 2.0 mg CuSO4.L-1. Copper sulphate also caused biochemical changes in both experiments. It was observed that this chemical causes a decrease in the concentration of GSH. The histopathological analysis showed hyperplasia and secondary lamellae fusion in the gills, and necrosis of the hepatopâncreas in both experiments. The tests results with C. dubia and P. subcapitata showed that copper sulphate caused acute toxicity to these organisms. This study showed that copper sulphate has caused chronic toxicity in fish and acute toxicity to algae and microcrustaceans. These results indicate that the pollutant can act at different trophic levels / Orientador: Maria José Tavares Ranzani Paiva / Coorientador: Julio Vicente Lombardi / Banca: José Roberto Ferreira / Banca: Fabiana Pilarski / Banca: Claudinei da Cruz / Banca: Monica Accaui Marcondes de Moura e Mello / Doutor
73

Charakterisierung und Weiterentwicklung eines Balanced Lethal Systems in \({Salmonella}\) \({spp}\) / Characterization and further development of a balanced lethal system in \({salmonella}\) \({spp}\)

Rechtenwald, Christian January 2011 (has links) (PDF)
Charakterisierung und Weiterentwicklung eines Systems zur antibiotikafreien Plasmidstabilisierung und Sekretion heterologer Antigene über das Hämolysin a-Sekretionssystem in attenuiereten Salmonella-Stämmen. Ziel ist die Entwicklung tumorspezifischer Vakzine. / Characterization and further development of a system for antibiotic-free plasmid stabilization in attenuated salmonella strains and secretion-enabling of heterologous antigens via the hemolysin a-secretion system. Goal is the development of tumor-specific vaccines.
74

The FIIND Domain of Nlrp1b Promotes Oligomerization and Pro-caspase-1 Activation in Response to Lethal Toxin of Bacillus anthracis

Joag, Vineet 29 November 2012 (has links)
Lethal toxin (LeTx) of Bacillus anthracis kills murine macrophages in a caspase-1 and Nod-like-receptor-protein 1b (Nlrp1b)-dependent manner. Nlrp1b detects intoxication, and self-associates to form a macromolecular complex called the inflammasome, which activates the pro-caspase-1 zymogen. I heterologously reconstituted the Nlrp1b inflammasome in human fibroblasts to characterize the role of the FIIND domain of Nlrp1b in pro-caspase-1 activation. Amino-terminal truncation analysis of Nlrp1b revealed that Nlrp1b1100-1233, containing the CARD domain and amino-terminal 42 amino acids within the FIIND domain was the minimal region that self-associated and activated pro-caspase-1. Residues 1100EIKLQIK1106 within the FIIND domain were critical for self-association and pro-caspase-1 activation potential of Nlrp1b1100-1233, but not for binding to pro-caspase-1. Furthermore, residues 1100EIKLQIK1106 were critical for cell death and pro-caspase-1 activation potential of full-length Nlrp1b upon intoxication. These data suggest that after Nlrp1b senses intoxication, the FIIND domain promotes self-association of Nlrp1b, which activates pro-caspase-1 zymogen due to induced pro-caspase-1 proximity.
75

The FIIND Domain of Nlrp1b Promotes Oligomerization and Pro-caspase-1 Activation in Response to Lethal Toxin of Bacillus anthracis

Joag, Vineet 29 November 2012 (has links)
Lethal toxin (LeTx) of Bacillus anthracis kills murine macrophages in a caspase-1 and Nod-like-receptor-protein 1b (Nlrp1b)-dependent manner. Nlrp1b detects intoxication, and self-associates to form a macromolecular complex called the inflammasome, which activates the pro-caspase-1 zymogen. I heterologously reconstituted the Nlrp1b inflammasome in human fibroblasts to characterize the role of the FIIND domain of Nlrp1b in pro-caspase-1 activation. Amino-terminal truncation analysis of Nlrp1b revealed that Nlrp1b1100-1233, containing the CARD domain and amino-terminal 42 amino acids within the FIIND domain was the minimal region that self-associated and activated pro-caspase-1. Residues 1100EIKLQIK1106 within the FIIND domain were critical for self-association and pro-caspase-1 activation potential of Nlrp1b1100-1233, but not for binding to pro-caspase-1. Furthermore, residues 1100EIKLQIK1106 were critical for cell death and pro-caspase-1 activation potential of full-length Nlrp1b upon intoxication. These data suggest that after Nlrp1b senses intoxication, the FIIND domain promotes self-association of Nlrp1b, which activates pro-caspase-1 zymogen due to induced pro-caspase-1 proximity.
76

Predicting temperature profiles during simulated forest fires

Enninful, Ebenezer Korsah 19 September 2006
Below-ground effects during forest fires are some of the important issues forest managers consider when conducting prescribed fire programs. Heat transfer models in soil are needed to predict temperatures in soil during forest fires. Many of the heat transfer models in soil that include the effects of moisture are complex and in most cases do not have very good predictive abilities. Researchers believe that simple heat transfer models in soil that neglect the effects of moisture could have very good predictive abilities.<p>This study presents a one-dimensional numerical model of heat transfer in dry homogenous sand. Both constant and temperature dependent thermal properties of the sand were used in order to determine which had better predictive abilities. The constant thermal properties model was also extended to a model of two-layer dry soil. A computer code written in Fortran was used to generate results from the model. A number of experiments were conducted with dry sand to validate the model. A comparison of the numerical and experimental results indicated that the temperature dependent properties model had better predictive abilities than the constant properties model. The models were found to do a good job of predicting temperature profiles and depth of lethal heat penetration at heat fluxes indicative of forest fires.<p>Experiments were also conducted to determine the effect of moisture on temperature profiles and the depth of lethal heat penetration in sand and the effect of inorganics on the spread rate of smoldering combustion in peat moss. An experimental correlation of the effects of inorganic content on the spread rate of smoldering combustion in peat moss was developed. Additionally, laboratory methods of validating models of heat transfer in soil were developed with the aim of limiting the dependence on full scale testing. Specifically the use of the cone calorimeter for validating numerical models of heat transfer in soil and the responses of forest floor soil and laboratory created soil samples to heat input were compared. The results indicated that the laboratory created soil did a very good job of mimicking the heat response of the forest floor soil with a maximum difference in lethal heat penetration of 4%.
77

Predicting temperature profiles during simulated forest fires

Enninful, Ebenezer Korsah 19 September 2006 (has links)
Below-ground effects during forest fires are some of the important issues forest managers consider when conducting prescribed fire programs. Heat transfer models in soil are needed to predict temperatures in soil during forest fires. Many of the heat transfer models in soil that include the effects of moisture are complex and in most cases do not have very good predictive abilities. Researchers believe that simple heat transfer models in soil that neglect the effects of moisture could have very good predictive abilities.<p>This study presents a one-dimensional numerical model of heat transfer in dry homogenous sand. Both constant and temperature dependent thermal properties of the sand were used in order to determine which had better predictive abilities. The constant thermal properties model was also extended to a model of two-layer dry soil. A computer code written in Fortran was used to generate results from the model. A number of experiments were conducted with dry sand to validate the model. A comparison of the numerical and experimental results indicated that the temperature dependent properties model had better predictive abilities than the constant properties model. The models were found to do a good job of predicting temperature profiles and depth of lethal heat penetration at heat fluxes indicative of forest fires.<p>Experiments were also conducted to determine the effect of moisture on temperature profiles and the depth of lethal heat penetration in sand and the effect of inorganics on the spread rate of smoldering combustion in peat moss. An experimental correlation of the effects of inorganic content on the spread rate of smoldering combustion in peat moss was developed. Additionally, laboratory methods of validating models of heat transfer in soil were developed with the aim of limiting the dependence on full scale testing. Specifically the use of the cone calorimeter for validating numerical models of heat transfer in soil and the responses of forest floor soil and laboratory created soil samples to heat input were compared. The results indicated that the laboratory created soil did a very good job of mimicking the heat response of the forest floor soil with a maximum difference in lethal heat penetration of 4%.
78

Back in the World: Vietnam Veterans through Popular Culture

McClancy, Kathleen January 2009 (has links)
<p>In his Dispatches, Michael Herr quotes the gonzo photojournalist Tim Page: "Take the glamour out of war! I mean, how the bloody hell can you do that?[...] Ohhhh, war is good for you, you can't take the glamour out of that. It's like trying to take the glamour out of sex, trying to take the glamour out of the Rolling Stones." This dissertation is in essence an exploration of Page's question, examining how popular media during the American conflict in Indochina first removed and then restored the glamour of war. For most of its history, the United States has been defined by a certain level of militarism, a glamorizing of the process of regeneration through violence reflected in this quotation, but the late 1960s and early 1970s saw a challenging of this warrior ethos; this challenge was reversed by the 1980s, when American militarism was taken to a new, paramilitary, level. In this project, I propose that this oscillation in the association of masculinity and violence was directly linked to popular media's depiction of the Vietnam war and of the soldiers who fought it. American society is haunted by Vietnam, not just because it was the first war the US lost (as the cliché would have it), but because of the ways in which popular culture presented the war to Americans: in particular, because of the ways the American public received this war through the emerging technologies of their television screens. The rapid response of television news to the conflict created an image of mundane warfare not through any intention on the part of broadcasters but because of the nature of the medium itself; over the next twenty years this image was both mystified and moderated by the more delayed media of film and literature and eventually molded into the now-familiar Vietvet killing machine.</p><p>In five chapters, I chronicle the evolution of the iconic Vietvet through the twenty years following the war. Following the methods of Raymond Williams and the Birmingham School, I trace the history and development of images from Vietnam as well as the interaction of those images with popular narratives of war, violence, masculinity and heroism in America. I start with Susan Jeffords' work in The Remasculization of America, taking her emphasis on the cultural narratives that fostered the restoration of patriarchal ideologies; I then move through Marita Sturken's discussion of the creation of cultural memory from historical artifacts in Tangled Memories. To these foundational texts, I bring an emphasis on form and technology to shift the focus from the narratives to the mechanisms of transmission themselves. In my first chapter, I show how the relatively new medium of television, and the depiction on the nightly news of Vietnam as both mundane and corrupt, called into question the image of the heroic soldier, finally replacing that image with the demon of the uncontrollable violent vet, driven insane by an unjust war. My next two chapters look at how this image was rehabilitated through its recharacterization in the less immediate channels of novels and film, a recharacterization driven by national debates over the diagnosis of PTSD and the design of the Vietnam Veterans Memorial. And in my final two chapters, I show how the image of the overly-muscled Supervet killing machine from pulps and blockbusters replaced the broken, victimized effigy.</p><p>I focus on the evolving history of veterans of the Vietnam War in particular because the strong interdependence of the history of that war and popular culture functions as a spotlight on the nature of the relation between media, history and cultural memory. Television coverage of the Vietnam War to a large extent worked not only to expose the inherent immorality of that particular conflict, but also of war more generally and of the image of the soldier hero. But in the two decades between the end of the Vietnam War and the first Gulf War, the standard history of the war had resolidified into one glorifying combat and violence. By looking at this changing social understanding of Vietnam, I hope to reveal the greater mechanisms by which the newly emerging media technologies of the 1960s through the 1980s drastically changed the nature of representation of warfare, violence, and masculinity: first routinizing, then rejecting, and finally enthroning the image of the explosively violent soldier yoked to the state.</p> / Dissertation
79

Somatic Sex Determination in D. melanogaster: Insights in the Establishment to Maintenance Transition

Gonzalez Rojos, Alejandra Noemi 2012 May 1900 (has links)
In Drosophila melanogaster, sex is determined at the preblastoderm stage via an Xchromosome counting mechanism. During this process embryos that carry two X chromosomes begin to develop as females while embryos with one X start the male developmental program. The Xlinked genes involved in sex determination, also called Xsignal elements (XSEs), are: sisterlessA (sisA), sisterlessB (sisB), unpaired (upd), and runt. These genes are responsible for the transcriptional activation of the master regulatory gene Sexlethal (Sxl). Expression of Sxl is initially accomplished only in females through activation of the establishment promoter SxlPe. Later in development, Sxl is transcribed in both sexes through a maintenance promoter, SxlPm, but functional Sxl protein is only produced in female flies. Since Sxl is at the top of the sex determination cascade, understanding its regulation is key to comprehend the process of sex determination. The experiments in this dissertation were designed to better understand two aspects of the sex determination mechanism: How the protein encoded by XSE element sisA interacts with SxlPe, and how the transition from regulation by SxlPe to regulation by SxlPm occurs. The sisA protein (SisA), as part of the bZIP protein family, is thought to bind to its target as a dimer, but a dimerization partner has not yet been found. This work uses knockouts and germline clones to examine interaction between sisA and three SisA partner candidates, atf4, CG16813, and CG16815. Although the evidence described here suggest that none of the three SisA partner candidates genetically interact with Sis, we cannot rule out the possibility of redundancy between the different candidate proteins. This research unravels the timing and regulation of SxlPm expression. I have shown, contrary to previous thought, that expression of SxlPe and SxlPm overlaps for a brief period. Several of the same proteins that are involved in the regulation of SxlPe, including the XSE sisB, also regulate SxlPm. This sex specific regulation leads to a sexually dimorphic pattern of activation and early expression of SxlPm. A common enhancer region was found to regulate SxlPe as well as SxlPm. These results highlight the importance of the transition between SxlPe and SxlPm for the proper establishment of sex determination and have implications for how the sex determination mechanism evolved.
80

Identification of Host Factors Required for Anthrax Lethal Toxin Intoxication Using Chemical Genetic and RNAi Approaches

Slater, Louise January 2011 (has links)
Bacterial toxins have co-opted host cell machinery in order to enter cells and exert their deleterious effects. Anthrax toxin is composed of the receptor binding protein protective antigen (PA), and the enzymatic subunits lethal factor (LF) and edema factor (EF), which form the binary toxin complexes lethal toxin, LeTx (PA + LF), and edema toxin, EdTx (PA + EF). PA binds to receptors on the surface of host cells and shuttles LF and EF into cells through the endocytic pathway. Upon endosome acidification, PA oligomers insert into the endosomal membrane and form functional pores that deliver LF and EF into the cytoplasm. Translocation of the N-terminal domain of LF, \(LF_N\), through PA pores formed in lipid bilayers in vitro does not require host machinery. However, translocation of the related fusion protein \(LF_N\)-DTA across the membrane of toxin-loaded endosomes in vitro requires the addition of cytosolic translocation factors that include the COPI coatamer complex. We performed high-throughput small molecule and RNAi screens to identify host factors required for LF translocation, using LeTx-induced cell death as a phenotype. We describe the characterization of small molecule inhibitors of LeTx-induced cell death that inhibit toxin entry. Further, we describe the role of the endosomal chaperone GRP78 and the cytoplasmic CCT chaperonin in toxin translocation. RNAi knockdown of GRP78 and CCT subunits inhibited LeTx and EdTx delivered through the endocytic pathway. CCT knockdown additionally inhibited translocation of LF through PA pores formed directly in the plasma membrane, while GRP78 had no effect. Furthermore, we show that the role of GRP78 in toxin translocation is specific to translocation from the early endosome. Together with biochemical data, we propose that GRP78 facilitates translocation by unfolding LF and EF at near-neutral pH. In addition, we show that in CCT-knockdown cells, lethal levels of toxin reach the endosome, suggesting that CCT has a role in translocation and/or refolding of LF and EF. These studies highlight previously unidentified strategies used by anthrax toxin to hijack host cellular machinery in order to gain access to the cytosol.

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