553 resultados para Repressed-ucs
Resumo:
It is remarkable the current planet’s situation of degradation and modification of natural assets and the considerable loss of the recovery power inherent to the ecosystems. Concomitant with this, all communities and species are suffering the consequences of these changes without planning. The creation of conservation units (UCs) through the National System of Conservation Units (SNUC) was a concrete action on the deliberateness of halting these processes, which, on the other hand, generated socio-environmental, geo-economical and cultural-political conflict of interests between traditional communities in the vicinity of these units, institutions, governmental entities and society in general. The country’s National Program of Environmental Education (ProNEA) provides the integration of the communities and UCs’ managers in a co-participative administration to solve these conflicts. The principles of Environmental Education (EA) leads the methodology found to change the socio-educational paradigms of traditional teaching, still existing in our society and intrinsically related to environmental problems, which are contrary to the dialogic pedagogy from Paulo Freire, that valorize popular knowledge, pro-active citizenship, as well as contrary to Ecopedagogy, that re-integrate human being on its natural environment, the Earth. One of the tools for starting environmental sensitization is the diagnosis by environmental perception of individuals. In this context, the objective of our work was to identify the environmental perception of Tenda do Moreno community located nearby Pau Furado State Park (PEPF) in Uberlândia – MG. To reach this objective, the research sought, in a first moment, to evaluate the environmental perception of residents of this community through semi-structured interviews applied in their homes and, in a second moment, we evaluated the environmental perception of community’ school students and made Environmental Education intervention activities with the intention to make children aware of the importance of conservation and function of PEPF. Using the Content analysis methodology, we found in nearly 60% of the 118 residents a systemic perception of nature, while approximately 32% expressed an anthropocentric perception. Mixed perceptions were found in 21%. A considerable part of the residents (47 individuals) indicated not knowing the park, although many of them recognize its importance. Among the 46 interviewed students, half expressed an anthropocentric perception of nature, while almost 36% had a systemic view. Seventeen children said they did not know the park and almost half of the students recognize some aspect of the importance of its existence. During the intervention activities, we had huge participation and dedication of students, beyond the massive expression of their personal views and daily experiences. In relation to the ten students that subjected the second evaluation about their environmental perception after the intervention, 80% showed systemic perception and emphasized the importance of conservation and of park. We believe that the continuity of the intervention activities could generate positive perspectives of socio-environmental effective changes in the daily school. Activities lead by Ecopedagogy and that encourage the citizen leadership in the young students are fundamental, while in the community, closer ties and dialog by UC’s managers would be important elements to generate effective change.
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Proper balancing of the activities of metabolic pathways to meet the challenge of providing necessary products for biosynthetic and energy demands of the cell is a key requirement for maintaining cell viability and allowing for cell proliferation. Cell metabolism has been found to play a crucial role in numerous cell settings, including in the cells of the immune system, where a successful immune response requires rapid proliferation and successful clearance of dangerous pathogens followed by resolution of the immune response. Additionally, it is now well known that cell metabolism is markedly altered from normal cells in the setting of cancer, where tumor cells rapidly and persistently proliferate. In both settings, alterations to the metabolic profile of the cells play important roles in promoting cell proliferation and survival.
It has long been known that many types of tumor cells and actively proliferating immune cells adopt a metabolic phenotype of aerobic glycolysis, whereby the cell, even under normoxic conditions, imports large amounts of glucose and fluxes it through the glycolytic pathway and produces lactate. However, the metabolic programs utilized by various immune cell subsets have only recently begun to be explored in detail, and the metabolic features and pathways influencing cell metabolism in tumor cells in vivo have not been studied in detail. The work presented here examines the role of metabolism in regulating the function of an important subset of the immune system, the regulatory T cell (Treg) and the role and regulation of metabolism in the context of malignant T cell acute lymphoblastic leukemia (T-ALL). We show that Treg cells, in order to properly function to suppress auto-inflammatory disease, adopt a metabolic program that is characterized by oxidative metabolism and active suppression of anabolic signaling and metabolic pathways. We found that the transcription factor FoxP3, which is highly expressed in Treg cells, drives this phenotype. Perturbing the metabolic phenotype of Treg cells by enforcing increased glycolysis or driving proliferation and anabolic signaling through inflammatory signaling pathways results in a reduction in suppressive function of Tregs.
In our studies focused on the metabolism of T-ALL, we observed that while T-ALL cells use and require aerobic glycolysis, the glycolytic metabolism of T-ALL is restrained compared to that of an antigen activated T cell. The metabolism of T-ALL is instead balanced, with mitochondrial metabolism also being increased. We observed that the pro-anabolic growth mTORC1 signaling pathway was limited in primary T-ALL cells as a result of AMPK pathway activity. AMPK pathway signaling was elevated as a result of oncogene induced metabolic stress. AMPK played a key role in the regulation of T-ALL cell metabolism, as genetic deletion of AMPK in an in vivo murine model of T-ALL resulted in increased glycolysis and anabolic metabolism, yet paradoxically increased cell death and increased mouse survival time. AMPK acts to promote mitochondrial oxidative metabolism in T-ALL through the regulation of Complex I activity, and loss of AMPK reduced mitochondrial oxidative metabolism and resulted in increased metabolic stress. Confirming a role for mitochondrial metabolism in T-ALL, we observed that the direct pharmacological inhibition of Complex I also resulted in a rapid loss of T-ALL cell viability in vitro and in vivo. Taken together, this work establishes an important role for AMPK to both balance the metabolic pathways utilized by T-ALL to allow for cell proliferation and to also promote tumor cell viability by controlling metabolic stress.
Overall, this work demonstrates the importance of the proper coupling of metabolic pathway activity with the function needs of particular types of immune cells. We show that Treg cells, which mainly act to keep immune responses well regulated, adopt a metabolic program where glycolytic metabolism is actively repressed, while oxidative metabolism is promoted. In the setting of malignant T-ALL cells, metabolic activity is surprisingly balanced, with both glycolysis and mitochondrial oxidative metabolism being utilized. In both cases, altering the metabolic balance towards glycolytic metabolism results in negative outcomes for the cell, with decreased Treg functionality and increased metabolic stress in T-ALL. In both cases, this work has generated a new understanding of how metabolism couples to immune cell function, and may allow for selective targeting of immune cell subsets by the specific targeting of metabolic pathways.
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A University of Hawaii oceanographic cruise, Abyssal Hills 69, with the R/V Mahi, was carried out to study the association of manganese nodules with an abyssal hill. Manganese nodules from three dredge hauls on an abyssal hill located at 36°W and 157°W exhibited differences in morphology and composition between stations only three miles apart. The morphology of the nodules suggests that nodules from a single site have similar morphologies because they began growth at the same time, probably because of a volcanic event. Differences in morphology between stations indicate a local supply of elements. Atomic absorption analysis for manganese, iron, cobalt, nickel, and copper revealed that nodules nearest to a probable fault line and source of volcanism have a, lower manganese to iron ratio than nodules farther removed. This finding supports the theory that volcanism contributes to the formation of some nodules. Additional evidence showing association with volcanism consists of volcanic nuclei in nodules, crusts formed on layers of volcanic ash, and basalt encrusted to various degrees. The variation in cobalt, nickel, and copper contents Gt the nodules from a single dredge is two-to threefold, but iron content is more uniiorm. Four of the six cores from the area increased in manganese concentration with depth, suggesting that diffusion is concentrating manganese in the upper zone of the sediments or in nodules. The author concludes that volcanism is contributing to the formation of nodules by supplying nuclei and transition elements, but is not necessary for the formation of manganese nodules.
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Les cellules endothéliales forment une couche semi-perméable entre le sang et les organes. La prolifération, la migration et la polarisation des cellules endothéliales sont essentielles à la formation de nouveaux vaisseaux à partir de vaisseaux préexistants, soit l’angiogenèse. Le facteur de croissance de l’endothélium vasculaire (VEGF) peut activer la synthase endothéliale du monoxyde d’azote (eNOS) et induire la production de monoxyde d’azote (NO) nécessaire pour la régulation de la perméabilité vasculaire et l’angiogenèse. β- caténine est une composante essentielle du complexe des jonctions d’ancrage ainsi qu’un régulateur majeur de la voie de signalisation de Wnt/β-caténine dans laquelle elle se joint au facteur de transcription TCF/LEF et module l’expression de nombreux gènes, dont certains sont impliqués dans l’angiogenèse. La S-nitrosylation (SNO) est un mécanisme de régulation posttraductionnel des protéines par l’ajout d’un groupement nitroso au niveau de résidus cystéines. Le NO produit par eNOS peut induire la S-nitrosylation de la β−caténine au niveau des jonctions intercellulaires et moduler la perméabilité de l’endothélium. Il a d’ailleurs été montré que le NO peut contrôler l’expression génique par la transcription. Le but de cette thèse est d’établir le rôle du NO au sein de la transcription des cellules endothéliales, spécifiquement au niveau de l’activité de β-caténine. Le premier objectif était de déterminer si la SNO de la β-caténine affecte son activité transcriptionnelle. Nous avons montré que le NO inhibe l’activité transcriptionnelle de β- caténine ainsi que la prolifération des cellules endothéliales induites par l’activation de la voie Wnt/β-caténine. Il est intéressant de constater que le VEGF, qui induit la production de NO via eNOS, réprime l’expression de AXIN2 qui est un gène cible de Wnt s’exprimant suite à la i i stimulation par Wnt3a et ce, dépendamment de eNOS. Nous avons identifié que la cystéine 466 de la β-caténine est un résidu essentiel à la modulation répressive de son activité transcriptionnelle par le NO. Lorsqu’il est nitrosylé, ce résidu est responsable de la perturbation du complexe de transcription formé de β-caténine et TCF-4 ce qui inhibe la prolifération des cellules endothéliales induite par la stimulation par Wnt3a. Puisque le NO affecte la transcription, nous avons réalisé l’analyse du transcriptome afin d’obtenir une vue d’ensemble du rôle du NO dans l’activité transcriptionnelle des cellules endothéliales. L’analyse différentielle de l’expression des gènes de cellules endothéliales montre que la répression de eNOS par siRNA augmente l’expression de gènes impliqués au niveau de la polarisation tels que : PARD3A, PARD3B, PKCZ, CRB1 et TJ3. Cette analyse suggère que le NO peut réguler la polarisation des cellules et a permis d’identifier des gènes responsables de l’intégrité des cellules endothéliales et de la réponse immunitaire. De plus, l’analyse de voies de signalisation par KEGG montre que certains gènes modulés par l’ablation de eNOS sont enrichis dans de nombreuses voies de signalisation, notamment Ras et Notch qui sont importantes lors de la migration cellulaire et la différenciation des cellules de têtes et de tronc (tip/stalk). Le regroupement des gènes exprimés chez les cellules traitées au VEGF (déplétées de eNOS ou non) révèle que le NO peut affecter l’expression de gènes contribuant au processus angiogénique, dont l’attraction chimiotactique. Notre étude montre que le NO module la transcription des cellules endothéliales et régule l’expression des gènes impliqués dans l’angiogenèse et la fonction endothéliale.
Resumo:
Le contexte de ce projet de recherche est celui de la stabilité des barrages-poids et aborde le besoin d’évaluation de la résistance de l’interface béton-rocher. Puisqu’il est techniquement difficile d’évaluer si l’interface est liée ou non, la cohésion réelle et sa contribution à la résistance au cisaillement sont souvent négligées et ce sujet précis est peu abordé dans la littérature. Un lien direct peut être fait entre cette non-considération et des travaux de stabilisation réalisés sur des ouvrages hydrauliques. Cette étude a comme objectif la caractérisation de la cohésion réelle dans le but de déterminer s’il est sécuritaire d’incorporer sa contribution dans l’évaluation de stabilité des barrages-poids. Pour ce faire, il est nécessaire d’évaluer les comportements en traction et en cisaillement de l’interface et d’analyser comment ils sont affectés par des paramètres importants telle la rugosité de l’interface. Cette caractérisation est faite à l’aide d’un programme expérimental sur 66 répliques d’interfaces béton-rocher en mortier. La rugosité est évaluée à l’aide d’un profilomètre laser et du paramètre Z2. Les répliques ont fait l’objet d’essais de traction directe, de traction par pression de fluide et de cisaillement direct. L’influence de la rugosité d’interface et de la résistance à la compression uniaxiale (UCS) des matériaux sur les résistances à la traction et au cisaillement est évaluée grâce à l’analyse des variances (ANOVA). Des essais supplémentaires ont permis d’approfondir la compréhension du mécanisme de rupture en cisaillement. Les résultats indiquent une résistance à la traction moyenne de l’interface liée de 0,62 MPa et une cohésion (en cisaillement) moyenne de 3,1 MPa. L’ANOVA montre une augmentation significative de la résistance à la traction avec la rugosité et une augmentation significative de la résistance au cisaillement au pic avec la rugosité, l’UCS et la contrainte normale. Il a aussi été observé que le pas d’échantillonnage a un impact important sur la valeur de Z2. Les résultats suggèrent qu’une valeur minimale de cohésion de 100 à 200 kPa pourrait être utilisée dans la mesure où il peut être démontré que l’interface est liée. Cette condition pourrait d’ailleurs constituer un sujet de recherche s’inscrivant dans la continuité des travaux réalisés.
Resumo:
The Group A Streptococcus (GAS), or Streptococcus pyogenes, is a strict human pathogen that colonizes a variety of sites within the host. Infections can vary from minor and easily treatable, to life-threatening, invasive forms of disease. In order to adapt to niches, GAS utilizes environmental cues, such as carbohydrates, to coordinate the expression of virulence factors. Research efforts to date have focused on identifying how either components of the phosphoenolpyruvate-phosphotransferase system (PTS) or global transcriptional networks affect the regulation of virulence factors, but not the synergistic relationship between the two. The present study investigates the role of a putative PTS-fructose operon encoded by fruRBA and its role in virulence in the M1T1 strain 5448. Growth in fructose resulted in induction of fruRBA. RT-PCR showed that fruRBA formed an operon, which was repressed by FruR in the absence of fructose. Growth and carbon utilization profiles revealed that although the entire fruRBA operon was required for growth in fructose, FruA was the main fructose transporter. The ability of both ΔfruR and ΔfruB mutants to survive in whole human blood or neutrophils was impaired. However, the phenotypes were not reproduced in murine whole blood or in a mouse intraperitoneal infection, indicating a human-specific mechanism. While it is known that the PTS can affect activity of the Mga virulence regulator, further characterization of the mechanism by which sugars and its protein domains affect activity have not been studied. Transcriptional studies revealed that the core Mga regulon is activated more in a glucose-rich than a glucose-poor environment. This activation correlates with the differential phosphorylation of Mga at its PTS regulatory domains (PRDs). Using a 5448 mga mutant, transcriptome studies in THY or C media established that the Mga regulon reflects the media used. Interestingly, Mga regulates phage-encoded DNases in a low glucose environment. We also show that Mga activity is dependent on C-terminal amino acid interactions that aid in the formation of homodimers. Overall, the studies presented sought to define how external environmental cues, specifically carbohydrates, control complex regulatory networks used by GAS, contribute to pathogenesis, and aid in adaptation to various nutrient conditions encountered.
Resumo:
Cellular exposure to hypoxia results in altered gene expression in a range of physiologic and pathophysiologic states. Discrete cohorts of genes can be either up- or down-regulated in response to hypoxia. While the Hypoxia-Inducible Factor (HIF) is the primary driver of hypoxia-induced adaptive gene expression, less is known about the signalling mechanisms regulating hypoxia-dependent gene repression. Using RNA-seq, we demonstrate that equivalent numbers of genes are induced and repressed in human embryonic kidney (HEK293) cells. We demonstrate that nuclear localization of the Repressor Element 1-Silencing Transcription factor (REST) is induced in hypoxia and that REST is responsible for regulating approximately 20% of the hypoxia-repressed genes. Using chromatin immunoprecipitation assays we demonstrate that REST-dependent gene repression is at least in part mediated by direct binding to the promoters of target genes. Based on these data, we propose that REST is a key mediator of gene repression in hypoxia.
Resumo:
During the early Stuart period, England’s return to male monarchal rule resulted in the emergence of a political analogy that understood the authority of the monarch to be rooted in the “natural” authority of the father; consequently, the mother’s authoritative role within the family was repressed. As the literature of the period recognized, however, there would be no family unit for the father to lead without the words and bodies of women to make narratives of dynasty and legitimacy possible. Early modern discourse reveals that the reproductive roles of men and women, and the social hierarchies that grow out of them, are as much a matter of human design as of divine or natural law. Moreover, despite the attempts of James I and Charles I to strengthen royal patriarchal authority, the role of the monarch was repeatedly challenged on stage and in print even prior to the British Civil Wars and the 1649 beheading of Charles I. Texts produced at moments of political crisis reveal how women could uphold the legitimacy of familial and political hierarchies, but they also disclose patriarchy’s limits by representing “natural” male authority as depending in part on women’s discursive control over their bodies. Due to the epistemological instability of the female reproductive body, women play a privileged interpretive role in constructing patriarchal identities. The dearth of definitive knowledge about the female body during this period, and the consequent inability to fix or stabilize somatic meaning, led to the proliferation of differing, and frequently contradictory, depictions of women’s bodies. The female body became a site of contested meaning in early modern discourse, with men and women struggling for dominance, and competitors so diverse as to include kings, midwives, scholars of anatomy, and female religious sectarians. Essentially, this competition came down to a question of where to locate somatic meaning: In the opaque, uncertain bodies of women? In women’s equally uncertain and unreliable words? In the often contradictory claims of various male-authored medical treatises? In the whispered conversations that took place between women behind the closed doors of birthing rooms? My dissertation traces this representational instability through plays by William Shakespeare, John Ford, Thomas Middleton, and William Rowley, as well as in monstrous birth pamphlets, medical treatises, legal documents, histories, satires, and ballads. In these texts, the stories women tell about and through their bodies challenge and often supersede male epistemological control. These stories, which I term female bodily narratives, allow women to participate in defining patriarchal authority at the levels of both the family and the state. After laying out these controversies and instabilities surrounding early modern women’s bodies in my first chapter, my remaining chapters analyze the impact of women’s words on four distinct but overlapping reproductive issues: virginity, pregnancy, birthing room rituals, and paternity. In chapters 2 and 3, I reveal how women construct the inner, unseen “truths” of their reproductive bodies through speech and performance, and in doing so challenge the traditional forms of male authority that depend on these very constructions for coherence. Chapter 2 analyzes virginity in Thomas Middleton and William Rowley’s play The Changeling (1622) and in texts documenting the 1613 Essex divorce, during which Frances Howard, like Beatrice-Joanna in the play, was required to undergo a virginity test. These texts demonstrate that a woman’s ability to feign virginity could allow her to undermine patriarchal authority within the family and the state, even as they reveal how men relied on women to represent their reproductive bodies in socially stabilizing ways. During the British Civil Wars and Interregnum (1642-1660), Parliamentary writers used Howard as an example of how the unruly words and bodies of women could disrupt and transform state politics by influencing court faction; in doing so, they also revealed how female bodily narratives could help recast political historiography. In chapter 3, I investigate depictions of pregnancy in John Ford’s tragedy, ‘Tis Pity She’s a Whore (1633) and in early modern medical treatises from 1604 to 1651. Although medical texts claim to convey definitive knowledge about the female reproductive body, in actuality male knowledge frequently hinged on the ways women chose to interpret the unstable physical indicators of pregnancy. In Ford’s play, Annabella and Putana take advantage of male ignorance in order to conceal Annabella’s incestuous, illegitimate pregnancy from her father and husband, thus raising fears about women’s ability to misrepresent their bodies. Since medical treatises often frame the conception of healthy, legitimate offspring as a matter of national importance, women’s ability to conceal or even terminate their pregnancies could weaken both the patriarchal family and the patriarchal state that the family helped found. Chapters 4 and 5 broaden the socio-political ramifications of women’s words and bodies by demonstrating how female bodily narratives are required to establish paternity and legitimacy, and thus help shape patriarchal authority at multiple social levels. In chapter 4, I study representations of birthing room gossip in Thomas Middleton’s play, A Chaste Maid in Cheapside (1613), and in three Mistris Parliament pamphlets (1648) that satirize parliamentary power. Across these texts, women’s birthing room “gossip” comments on and critiques such issues as men’s behavior towards their wives and children, the proper use of household funds, the finer points of religious ritual, and even the limits of the authority of the monarch. The collective speech of the female-dominated birthing room thus proves central not only to attributing paternity to particular men, but also to the consequent definition and establishment of the political, socio-economic, and domestic roles of patriarchy. Chapter 5 examines anxieties about paternity in William Shakespeare’s The Winter’s Tale (1611) and in early modern monstrous birth pamphlets from 1600 to 1647, in which children born with congenital deformities are explained as God’s punishment for the sexual, religious, and/or political transgressions of their parents or communities. Both the play and the pamphlets explore the formative/deformative power of women’s words and bodies over their offspring, a power that could obscure a father’s connection to his children. However, although the pamphlets attempt to contain and discipline women’s unruly words and bodies with the force of male authority, the play reveals the dangers of male tyranny and the crucial role of maternal authority in reproducing and authenticating dynastic continuity and royal legitimacy. My emphasis on the socio-political impact of women’s self-representation distinguishes my work from that of scholars such as Mary Fissell and Julie Crawford, who claim that early modern beliefs about the female reproductive body influenced textual depictions of major religious and political events, but give little sustained attention to the role female speech plays in these representations. In contrast, my dissertation reveals that in such texts, patriarchal society relies precisely on the words women speak about their own and other women’s bodies. Ultimately, I argue that female bodily narratives were crucial in shaping early modern culture, and they are equally crucial to our critical understanding of sexual and state politics in the literature of the period.
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My novel, 'How Long the Night,' and my essay, ‘The Ghosts of Muranów: Confronting Poland’s Jewish Past,’ focus on the relationship between urban space, memory and identity. Before the Second World War Muranów was one of the largest Jewish districts in Europe. In August 1939 Poland’s capital was home to 380,000 Jews, which accounted for about 30 percent of the city’s total population. During the war the district was the central part of the Warsaw Ghetto located near the Umschlagplatz, the place from which Jews were transported to concentration camps. After the failed uprising in 1943 the Nazis burnt the entire quarter to the ground. There was nothing left, except for heaps of rubble. The debris was to be the foundation on which the new socialist realist residential district would stand. The new Muranów, erected on the ashes of the former ghetto, is a space of absence, emptiness and repressed guilt. There are no physical traces of the Jewish presence in the area, except for commemorative plaques, monuments or obelisks. Former tenement houses, shops, synagogues are gone; street names and their layout are different as well. Nevertheless, the former Jewish district is present in images, dreams (or nightmares), in fantasies, memories and stories. My novel and my essay explore the connection between place, history, memory and trauma. The space of Muranów becomes a symbolic trigger for investigation and re-examination of the forgotten or suppressed past. What is more, the novel examines the way a foreign language serves as a tool through which painful and repressed stories can be (re)told.
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Over time, humanity began to realize the negative impact that the modern world has caused to the environment. The Atlantic Forest is one of the richest biomes in biodiversity, covering more than 60% of all species on the planet. This biome covered about 15% of the Brazilian territory, leaving currently only 7% of its fully fragmented forest remnants. This was the biome that suffered most from modernization and strong anthropogenic pressures in Brazil. For the account of environmental degradation, in the second half of the nineteenth century there was a shift in thinking, giving greater emphasis on conservation of some natural landscapes, with the intention of removing the man still preserved nature. Based on American models of conservation there were created the Nature Conservation Units. This study aimed to analyze the environmental quality of the State Park Vitório Piassa, a Conservation Unit located in the city of Pato Branco - PR. The environmental quality was measured by use of bio-indicators and some environmental pressures that the Park has suffered over the years also were identified. Beetles of the familiy Scarabaeinae (Coleoptera: Scarabaeidae) were used as the bioindicators. To compare the most conserved areas and the most degraded areas of the Park, three specific sites were defined within the Atlantic Forest fragment, these insects were captured with pitfall traps and identified as to their species and genera. There were two collections in February and March 2015, which resulted in 945 individuals in 22 species and nine different genus. Then the population of beetles in each area were classified based on ecological measures such as species richness, abundance of individuals of each species through diversity index (Shannon and Simpson) to identify the differences between the sampled groups and equitability (Pielou) to measure the distribution of the total abundance of the species in each area. To meet the objective of identifying the environmental pressures that occur in PEVP, evidence were collected through photographs, watching the field, aerial images and conversations with the resident population in the park. Similarly, if made relevant to build on the project running by the municipality for the construction of infrastructure for public viewing. These data served as subsidies to confront the current situation of the park and the current Brazilian legislation for UC's of full protection, highlighting the existing socio-environmental conflicts in the park, involving political issues and the proximity of the Conservation Unit with the urban area of the city.
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Flowering is a fundamental process in the life cycle for plant. This process is marked by vegetative to reproductive apical meristem conversion, due to interactions between several factors, both internal and external to plant. Therefore, eight subtractive libraries were constructed using apical meristem induced or not induced for two contrasting species: Solanum lycopersicum cv. Micro-Tom and Solanum pimpinellifolium. Several cDNAs were identified and among these, were selected two cDNAs: one homologous cDNA to cyclophilin (LeCYP1) and the other to Auxin repressed protein (ARP). It has observed that LeCYP1 and ARP genes are important in the developmental process to plants. In silico analysis, were used several databases with the exclusion criterion E-value <1.0x10-15. As a result, conservation was observed for proteins analyzed by means of multiple alignments and the presence of functional domains. Then, overexpression cassettes were constructed for the ARP cDNA in sense and antisense orientations. For this step, it was used the CaMV35S promoter. The cDNA orientation (sense or antisense) in relation to the promoter was determined by restriction enzymes and sequencing. Then, this cassette was transferred to binary vector pZP211 and these cassettes were transferred into Agrobacterium tumefaciens LBA4404. S. lycopersicum cv. Micro-Tom (MT) and MT-Rg1 plants were transformed. In addition, seedlings were subjected to hormone treatments using a synthetic auxin (- naphthalene acetic acid) and cyclosporin A (cyclophilin inhibitor) treatments and it was found that the hormone treatment there were changes in development of lateral roots pattern, probably related to decreases in auxin signaling caused by reduction of LeCYP1 in MT-dgt plants while cyclosporin A treatments, there was a slight delay in flowering in cv. MT plants. Furthermore, assay with real-time PCR (RT-qPCR) were done for expression level analysis from LeCYP1 and ARP in order to functionally characterize these sequences in tomato plants.
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Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Humanas, Departamento de Geografia, Programa de Pós Graduação em Geografia, 2015.
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Quizás sea conveniente recordar que en 1972 un terremoto destruyó las principales bibliotecas de Nicaragua. Durante la insurrección de 1979 fueron saqueadas o destruidas las demás. La mayoría de los profesionales huyó quedando únicamente 17 bibliotecarios en el país.La gran cruzada de Alfabetización en 1980, que se planteó como primer tarea revolucionaria, produjo un aumento en la población lectora de 400.000 personas en solo un año. Cómo atender a los usuarios antiguos y a esta nueva avalancha que llegó a los centros educativos con una videz reprimida durante cuarenta años de dictadura?