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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.
231

Avaliação dos efeitos renais da fração L-aminoácido Oxidase isolada do veneno da serpente Bothrops marajoensis

Dantas, Rodrigo Tavares January 2010 (has links)
DANTAS, Rodrigo Tavares. Avaliação dos efeitos renais da fração L-aminoácido oxidase isolada do veneno da serpente Bothrops marajoensis. 2010. 104 f. Dissertação (Mestrado em Farmacologia) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2010. / Submitted by denise santos (denise.santos@ufc.br) on 2012-05-15T12:10:30Z No. of bitstreams: 1 2010_dis_rtdantas.pdf: 3573132 bytes, checksum: 27b964204fc5e26e329b4d9950fd7885 (MD5) / Approved for entry into archive by Eliene Nascimento(elienegvn@hotmail.com) on 2012-05-15T16:29:18Z (GMT) No. of bitstreams: 1 2010_dis_rtdantas.pdf: 3573132 bytes, checksum: 27b964204fc5e26e329b4d9950fd7885 (MD5) / Made available in DSpace on 2012-05-15T16:29:18Z (GMT). No. of bitstreams: 1 2010_dis_rtdantas.pdf: 3573132 bytes, checksum: 27b964204fc5e26e329b4d9950fd7885 (MD5) Previous issue date: 2010 / There are about 3.000 species of snakes worldwide, but only 10 to 14% are venomous. Among South American countries, Brazil is the one with the largest number of accidents, with approximately 20.000 snakebites each year. According to the Department of Health of Brazil, the genus Bothrops are the main involved in snakebites in the country. Acute renal failure (ARF) is a serious complication of snake poisoning. The fraction L-amino acid oxidase (LAAO) constitutes a main part of the total composition of snake venoms. In some cases this amount can reach 30% of total venom proteins. The renal effects of fraction L-amino acid oxidase isolated from the venom of Bothrops marajoensis (LAAOBM) was investigated in this study. Isolated perfused rat kidney and the cultured renal tubular cells line MDCK (Madin-Darby Canine Kidney) were used here. For the isolated perfused rat kidney method, we used Wistar rats weighing between 250 and 300. Their right kidneys were surgically excised and perfused with Krebs-Hanseleit containing 6% w/v bovine albumin previously dialyzed. The effects of LAAOBM (10 mg/mL, n=4) were analyzed on the Perfusion Pressure (PP), Renal Vascular Resistance (RVR), Urinary Flow (UF), Glomerular Filtration Rate (GFR) Percentage of Sodium Proximal Tubular Transport (%pTNa+), Percentage of Sodium (%TNa+), Potassium (%TK+) and Chloride (%TCl-) Tubular Transport. MDCK cells were cultured in RPMI 1640 medium supplemented with 10% v/v fetal bovine serum and incubated with LAAOBM at concentrations of 50, 25, 12.5, 6.25, 3.125 and 1.652 mg/mL. After 24 hours of incubation, assays were performed on cell proliferation and viability using the MTT method. The LAAOBM promoted a reduction of perfusion pressure at 90 minutes of the experiment and this reduction was even slightly higher at 120 minutes. It was also observed decrease in renal vascular resistance at 120 minutes. There was a sharp and sudden drop in urine flow at 90 minutes, despite the tendency of recovery observed at 120 minutes, still proved to be quite small when compared to the control group. The infusion of LAAOBM also promoted a reduction in glomerular filtration rate at 90 minutes compared to the control group and this parameter still remained at the same level of reduction at 120 minutes. The LAAOBM gradually reduced the percentage of sodium tubular transport at 90 and 120 minutes and the percentage of chloride tubular transport in the periods of 60, 90 and 120 minutes. Histological analysis of kidneys perfused with LAAOBM showed the presence of significant morphological changes such as accumulation of proteins in tubular and glomerular spaces. In the MDCK cell culture LAAOBM promoted a reduction in cell viability from concentrations of 3.25 mg / mL until 50μg/mL, with IC50 value of 2.43 mg/mL. Inverted light microscopy showed morphological changes of these cells, such as vacuolation, alteration of the state of confluence and detachment of the substrate culture. These results demonstrated that LAAOBM changed all the parameters evaluated in renal and vascular perfusion of isolated kidney and had cytotoxic activity on MDCK cells after 24 hours of incubation. / No mundo, existem cerca de 3.000 espécies de serpentes das quais 10 a 14% são peçonhentas. Dentre os países sul-americanos, o Brasil é o que apresenta maior número de aciden¬tes/ano com cerca de 20.000 acidentes ofídicos por ano. De acordo com o Ministério da Saúde, as serpentes do gênero Bothrops são as principais envolvidas nos acidentes ofídicos no país e a insuficiência renal aguda (IRA) é uma complicação grave dos envenenamentos produzidos por estas serpentes. Tendo em vista que a fração L-aminoácido oxidase (LAAO) constitui grande parte da composição total do veneno de serpentes, em algumas serpentes chegando a constituir mais de 30% do total de proteínas do veneno, neste trabalho, foram investigados os efeitos renais da fração L-aminoácido oxidase isolada do veneno da serpente Bothrops marajoensis (LAAOBM) em sistema de perfusão de rim isolado e em cultura de células tubulares renais da linhagem MDCK (Madin-Darby Canine Kidney). Para perfusão de rim isolado foram utilizados ratos Wistar pesando entre 250 e 300g, cujos rins foram excisados cirurgicamente e perfundidos com solução de Krebs-Hanseleit contendo 6%p/v de albumina bovina previamente dialisada. Foram investigados os efeitos da LAAOBM (10 µg/mL; n=4) sobre a Pressão de Perfusão (PP), Resistência Vascular Renal (RVR), Fluxo Urinário (FU), Ritmo de Filtração Glomerular (RFG), Percentual de Transporte Tubular Proximal de Sódio (%pTNa+),Percentual de Transporte Tubular de Sódio (%TNa+), de Potássio (%TK+) e de Cloreto (%TCl-). As células MDCK foram cultivadas em meio de cultura RPMI 1640 suplementado com 10% v/v de Soro Bovino Fetal e então incubadas com a LAAOBM nas concentrações de 50; 25; 12,5; 6,25; 3,125 e 1,652 µg/mL. Após 24 horas de incubação, foram realizados os ensaios de viabilidade e proliferação celular utilizando-se o método do MTT. A LAAOBM promoveu uma redução da pressão de perfusão aos 90 minutos de experimento e esta redução foi ainda discretamente maior aos 120 minutos. Observou-se também queda da resistência vascular renal aos 120 minutos. Houve uma queda abrupta e acentuada do fluxo urinário aos 90 minutos que, apesar da tendência à recuperação observada aos 120 minutos, ainda mostrou-se bastante reduzido quando comparado ao grupo controle. A infusão da LAAOBM também promoveu uma redução do ritmo de filtração glomerular aos 90 minutos quando comparada ao grupo controle e este parâmetro manteve-se ainda no mesmo patamar de redução aos 120 minutos. A LAAOBM reduziu gradativamente o percentual de transporte tubular de sódio aos 90 e 120 minutos e o percentual de transporte tubular de cloreto nos tempos de 60, 90 e 120 minutos. A análise histológica dos rins perfundidos com LAAOBM mostrou a presença de alterações morfológicas significativas, como acúmulo de proteínas nos espaços tubulares e glomerulares. Na cultura de células MDCK a LAAOBM promoveu uma redução da viabilidade celular a partir da concentração de 3,25µg/mL até a concentração de 50µg/mL, com valor da CI50 de 2,43µg/mL. Foram observadas também, através de microscópio óptico invertido, alterações morfológicas destas células, tais vacuolização citoplasmática, alteração do estado de confluência e desprendimento das mesmas do substrato de cultura. Estes resultados demonstram que a LAAOBM alterou todos os parâmetros vasculares e renais avaliados na perfusão de rim isolado e possui ação citotóxica sobre as células MDCK após 24 horas de incubação.
232

Studium variability a dědivosti kvalitativních znaků u řebříčku (Achillea L.)

Karlová, Kateřina January 2005 (has links)
Angl. resumé
233

Organisational learning in the university : a case study of change in higher education

McKenzie, Dawn January 2017 (has links)
Higher education is facing many challenges as universities contend with significant ongoing dynamic change in the external environment. As student expectations and needs evolve, many universities are reviewing the systems they use to support their business processes. This study investigates the process of change using a theoretical framework which combines the related concepts of organisational learning and knowledge management, underpinned by a complexity theory paradigm. Examining the experience of one university over a period of several years, the study identifies the changes which have impacted upon academic advising staff using a case study methodology which has been informed by action research. This methodology employs a mixed methods approach which facilitates a deeper understanding of the source of problems and enables the critique of organisational systems. Using the knowledge management techniques of collaboration, mapping and taxonomies, the study involved processual enquiry and review as new knowledge emerged and was placed within the context of the wider organisation (Dawson, 2014). The Burke-Litwin Causal Model of Organizational Performance and Change (Burke and Litwin, 1992) was employed to analyse organisational documentation and focus group feedback and the complexity inherent in higher education and the causal effects of organisational change are examined. Such an investigation provides a means by which the discrepancies between the university’s espoused theory and its theory-in-use (Argyris and Schön, 1978) can be identified and used to enhance organisational learning within the university. The main findings reveal tensions which arise from the ‘loosely versus tightly coupled systems’ of the university (Burke, 2014) and from the requirement for staff to place new and revised processes within their knowledge of previous systems. Recommendations are made which are aimed at improving advising and student records system processes as well as enhancing knowledge management and organisational learning within higher education.
234

The relationship between technology integration and the development of global citizenship skills and attitudes in a Lebanese context

Nicolas, Samira Selwa January 2017 (has links)
Information and communication technologies have seen exponential growth and development in the last few decades, therefore increasing the conditioning force they exert on power, knowledge, and creativity in the 21st century. This research aims to contribute to the discussion of 21st century globalization, from an educational perspective, and from the perspective of a developing country, Lebanon. Notable sociologist Manuel Castells’s theory of the network society provides the conceptual framework within which this thesis is situated. This thesis explores the integration of technology into the teaching process, and further seeks to investigate the relationship between technology integration and the development of students’ global citizenship skills and attitudes in a sample of Lebanese private high schools. Through a mixed methods approach to data gathering, data was gathered from 119 students and 41 teachers through the use of surveys, semi-structured interviews, and focus groups. The data was analyzed using descriptive statistics and inductive emergent theme strategies. Two participant populations (students and teachers) were included to provide a complete context within which to interpret the findings. This research displays originality by suggesting the existence of a relationship between technology use in school and the development in students of the skills and attitudes characteristic of a global citizen. The analysis revealed that most students exhibit the attitude of a global citizen regardless of how technology is being used in their classes. Therefore a strong relationship between technology integration in school and students’ global citizenship attitudes was not apparent. However, a relationship did emerge between a particular technology attitude held by some participants and their global citizenship attitude, leading to a conclusion that increased exposure to technology in school, in various forms, can make students more aware of the importance of digital skills and consequently more globally conscious.
235

Transforming transitions : the performance of motherhood and the school choice process

O'Neill, Helen January 2017 (has links)
Giving parents a choice regarding which schools educate their children has been central to the discourse of school choice in England for many years. This choice and the capacity to make it has implications for all concerned. However, little research has been done on the impact this choice, and the transition has on the way that women perform motherhood during this time. This study aimed to investigate and understand the effect of the school choice process on the mothers of children undergoing this transition and the ways they perform motherhood. Carried out in a small, rural area in East Anglia, this case study used a narrative approach to interview 15 mothers who had been through or were going through the process. The results of the research show that the transition to secondary school was a critical site of performativity and a catalyst for the women’s exploration of how they performed motherhood. Also, the research showed that the mothers all placed an importance on the local community as part of their performance of motherhood, linking the physical with the performative arenas. Contrary to previous research, the engagement with the process and the experiences of the mothers were not shared and were carried out on a private basis. This research leads to a greater understanding of the impact of the school choice process on mothers and their performance of motherhood and expands upon the decisions made and the way the educational market operates.
236

Efeito da suplementação dietética de aminoácidos nas camadas submucosa e muscular da parede ileal em ratos submetidos a irradiação abdominal / Effect of dietary amino acids in the submucosal and muscular layers of the ileal wall in rats subjected to abdominal irradiation.

Mônica Vieira Mano de Souza 11 February 2009 (has links)
A radioterapia é amplamente empregada no tratamento de tumores abdominais. Entretanto, o seu emprego provoca danos indesejáveis ao tecido sadio, especialmente o intestinal, refletidos por meio de manifestações clínicas e histológicas. Buscando minimizar esses efeitos colaterais, inúmeras alternativas vêm sendo estudadas, dentre elas a suplementação dietética com aminoácidos. O objetivo deste estudo foi determinar o efeito da suplementação dietética com os aminoácidos L-glutamina, L-arginina e glicina nas camadas submucosa e muscular do íleo de ratos submetidos a irradiação abdominal. Cinqüenta ratos Wistar machos adultos foram distribuídos aleatoriamente em cinco grupos: I Controle não irradiado e sem suplementação de aminoácidos; II Controle irradiado e sem suplementação de aminoácidos; III irradiado e suplementado com L-glutamina; IV irradiado e suplementado com glicina; V irradiado e suplementado com L-arginina. O período de suplementação dietética foi de 14 dias, com a irradiação ocorrendo no 8. dia do experimento. A irradiação provocou diminuição da espessura da camada submucosa dos animais do grupo II, como também do conteúdo de colágeno, em comparação ao grupo controle não irradiado. A suplementação com L-arginina e glicina provocou aumento expressivo da espessura da camada submucosa, enquanto a suplementação com L-glutamina manteve a espessura dessa camada similar à observada nos animais não irradiados. Os animais com dieta suplementada com L-arginina e glicina também apresentaram aumento da espessura da camada muscular circular interna, em comparação aos ratos dos grupos I, não se observando diferenças no que se refere à camada muscular longitudinal externa. A suplementação com aminoácidos levou a aumento na intensidade de imunomarcação de colágeno tipo I nos animais do grupo IV, menos marcante no grupo III, e o grupo V foi o que mais se assemelhou ao observado nos animais não-irradiados. No tocante ao colágeno tipo III, a imunomarcação foi mais intensa no grupo IV, menos marcante no grupo V, e no grupo de ratos suplementado com L-glutamina, foi similar à encontrada nos animais não-irradiados. Os resultados sugerem que a suplementação dietética com glicina e L-arginina leva a aumento da quantidade de colágeno na parede ileal de ratos submetidos a radioterapia abdominal, eventualmente predispondo ao surgimento de fibrose intestinal, enquanto que a suplementação com L-glutamina propicia a manutenção da espessura da camada submucosa e pode contribuir para a atenuação dos efeitos colaterais decorrentes da irradiação. / Radiotherapy is widely employed in the treatment of abdominal tumors. Nevertheless, its use damages healthy tissue, especially intestinal tissue, with consequent clinical and histological manifestations. In order to minimize these side effects, several alternatives are being studied, including dietary supplementation with amino acids. The aim of this study was to determine the effect of dietary supplementation with L-glutamine, L-arginine, and glycine on the submucosal and muscular layers of the ileum of rats submitted to abdominal radiation. Fifty male Wistar rats weighing 255 to 325 g were randomly divided into five groups: I Control not irradiated and not supplemented with amino acids; II Control irradiated but not supplemented with amino acids; III irradiated and supplemented with L-glutamine; IV irradiated and supplemented with glycine; V irradiated and supplemented with L-arginine. The period of dietary supplementation lasted 14 days, with radiation taking place on the 8th day of the experiment. Radiation determined a decrease in the thickness and in the collagen content of the submucosal layer in group II animals compared to the non-irradiated group. Supplementation with L-arginine and glycine induced a marked increase in the thickness of the submucosal layer, while supplementation with L-glutamine caused no changes compared to non-irradiated animals. The animals receiving a diet supplemented with L-arginine and glycine also showed increased thickness of the internal circular muscle layer compared to group I rats, with no difference in the external longitudinal muscle layer. Supplementation with amino acids led to increased immunostaining of type 1 collagen in group IV animals, with less intense staining in group III and no difference in group V compared to non-irradiated animals. Regarding type III collagen, immunostaining was more intense in group IV and less intense in group V, while in rats supplemented with L-glutamine there was no difference compared to non-irradiated animals. These results suggest that dietary supplementation with glycine and L-arginine induces an increase in the collagen content of the ileal wall of rats submitted to abdominal radiotherapy, eventually predisposing it to intestinal fibrosis, while supplementation with L-glutamine favors the maintenance of the submucosal layer thickness and can contribute to attenuating the side effects of radiation.
237

Efeito protetor da L-arginina e L-glutamina no pênis de ratos submetidos à irradiação pélvica / Protective effects of L-arginine and L-glutamine on the penis of rats submitted to pelvic radiation

Jorge Luiz Medeiros Júnior 28 July 2010 (has links)
Os aminoácidos L-arginina e L-glutamina foram analisados como protetores dos tecidos erétil do pênis contra os danos induzidos pela radiação. Grupos de ratos Wistar foram tratadas com: nenhuma intervenção, radiação pélvica e sacrifício 7 (RAD7) ou 15 (RAD15) dias; e radiação pélvica, a suplementação diária com L-arginina (A) ou L-glutamina (G), e sacrifício 7 (RAD7 + A, RAD7 + G) ou 15 (RAD15 + A, RAD15 + G) dias após irradiação. componentes estruturais do corpo cavernoso (CC), túnica albugínea do corpo esponjoso (TAC), e urotélio do pênis foram analisados através de métodos estereológicos e imuno-histoquímico. Os resultados mostraram que, no CC, o tecido conjuntivo foi maior nos RAD15 (p <0,04), mas essa mudança foi parcialmente revertido em RAD15 + G (p <0,05) e RAD15 + A (p <0,04). A matriz fibrosa das trabéculas CC estava manchada de colágeno tipo I. Nos RAD15, a intensidade da marcação foi aumentada, enquanto que em RAD15 + G + A e RAD15 a coloração era semelhante à dos controles. Nenhuma alteração de coloração foram observadas nos grupos que foram sacrificados sete dias após a radiação. Cavernosa teor de fibras elásticas na RAD15 foi aumentada (p <0,004), e este foi impedido de RAD15 + A (p <0,004), mas não em RAD15 + G. No TAC, os aminoácidos protegidos (p <0,02) contra o aumento da radiação induzida em fibras elásticas, mas apenas em RAD15. Densidade das células do urotélio e espessura urothellial, foram reduzidos em RAD15 (p <0,004), mas houve efeitos protetores dos dois aminoácidos. Em conclusão, a radiação induzida por alterações nas estruturas penianas tendem a ser mais pronunciado 15 dias após a sessão de radiação. Tanto A e G têm efeitos protetores contra estas alterações, sendo o primeiro um pouco mais eficaz. / We investigated whether arginine and glutamine protect penile tissues against radiation-induced damage. Groups of Wistar rats were treated with: no intervention; pelvic radiation, and sacrifice 7 (RAD7) or 15 (RAD15) days later; and pelvic radiation, daily supplementation with L-arginine (A) or L-glutamine (G), and sacrifice 7 (RAD7+A, RAD7+G) or 15 (RAD15+A, RAD15+G) days after radiation. Structural components in the corpus cavernosum (CC), tunica albuginea of the corpus spongiosum (TACS), and urothelium of the penis were analyzed using stereological and immunohistochemical methods. The results showed that in the CC, connective tissue was increased in RAD15 (p<0.04), but this change was partially prevented in RAD15+G (p<0.05) and RAD15+A (p<0.04). The fibrous matrix of the CC trabeculae was stained for collagen type I. In RAD15, the intensity of the labeling was increased, whereas in RAD15+G and RAD15+A the staining was similar to that of the controls. No staining changes were seen in the groups that were sacrificed seven days after radiation. Cavernosal elastic fiber content in RAD15 was increased (p<0.004), and this was prevented in RAD15+A (p<0.004), but not in RAD15+G. In TACS, the aminoacids protected (p<0.02) against radiation-induced increase in elastic fiber content, but only in RAD15. Cell density in the urothelium, and urothellial thickness, were reduced in RAD15 (p<0.004), but there were protective effects of both aminoacids. In conclusion, radiation-induced alterations in penile structures tend to be more pronounced 15 days after radiation session. Both A and G have protective effects against these changes, with the former being slightly more effective.
238

Estudo da resposta imunológica induzida por Arnica montana L

Marques, Márcia Faria [UNESP] 28 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-28Bitstream added on 2014-06-13T19:03:11Z : No. of bitstreams: 1 marques_mf_dr_arafcf.pdf: 489556 bytes, checksum: 3a823a4709ec5fb7e7742d4749cdba7f (MD5) / Universidade Estadual Paulista (UNESP) / A resposta imunológica engloba amplo contexto envolvendo várias células, sendo o macrófago uma das mais importantes na resposta imune-celular. Os macrófagos peritoneais quando ativados liberam mais de cem compostos ao meio extracelular, entre eles os compostos reativos de oxigênio e de nitrogênio, além das citocinas: fator de necrose tumoral-a (TNF-a), interferon-g (IFN-g) e interleucinas (IL-1, 4, 6 e 12). Existem vários estímulos à membrana macrofágica que podem desencadear a liberação de NO, contribuindo para uma ação antimicrobiana, inflamatória, vasodilatadora, neurotransmissora, ou até mesmo de citotoxicidade ou inibição/ativação linfocitária e da agregação de plaquetas. Atualmente há uma forte tendência em se estudar produtos naturais quanto à capacidade de atuação no sistema imunológico. Os medicamentos homeopáticos, conhecidos há mais de 210 anos, visam à ativação das próprias defesas do organismo para eliminar a doença. Estudos baseados em cultivos obtidos de macrófagos podem ser úteis para um melhor entendimento da resposta imunológica. Considerando a importância farmacológica de Arnica montana L. (Asteraceae), planta originária das regiões montanhosas do norte da Europa, este estudo avaliou a liberação de H2O2, NO, TNF-a, IFN-g e IL-1, 4, 6 e 12 no sistema imunológico através de macrófagos peritoneais expostos a preparações fitoterápicas e homeopáticas desta planta. Os resultados mostraram que a Arnica montana L. foi capaz de promover a liberação de NO, TNF-a, IFN-g e IL-6. As preparações homeopáticas também apresentaram um efeito inibitório na produção de NO e TNF-a induzida pelo LPS. A análise dos resultados deste trabalho sugere que a Arnica montana L. pode modular a ativação dos macrófagos. / The immunological response includes wide context involving several cells, being the macrophage one of the most important in the cellular immune response. The peritoneal macrophages when activated they liberate more than a hundred compound to the environment extracellular, among them compound reactive of the oxygen and nitrogen and the tumoral necrosis factor -a (TNF-a), gamma-interferon and interleukynes. The nitric oxide (NO) it is synthesized by several cellular types through isoforms of the enzyme nitric oxide synthase (NOS). The enzyme inducible nitric oxide synthase (iNOS) it produces NO starting from activators mechanisms macrophages. Several incentives to the membrane macrophagical that can unchain the liberation of NO, contributing to actions antibacterial, inflammatory, vasodilatation, neurotransmission, or even of citotoxicity or inhibition/activation of lymphocytes. Now there is a strong tendency in studying natural products with relationship to the capacity of performance in the immune system. Macrophages are involved in many different processes but their main function is to provide a defense line against microbial invasion and tumor cells. Once homeopathic medications are aimed at activation of the body's own defense mechanisms to fight an existing disease, assays based in macrophages culture may be useful to enlighten some questions. Considering the pharmacological importance of Arnica montana L. this study evaluated the action of NO in the immune system through peritoneal macrophages exposed to the preparations of this plant. The results showed that some of the tested preparations were capable to promote the liberation of NO, TNF-a, INF- e IL-6 in cultures of peritoneal macrophages murine. A relationship among the synthesis of NO and TNF- was observed. Analyzing the results, it is suggested that preparations of Arnica montana L. can modulate macrophage activation.
239

Filogenia de Passiflora L. (Passifloraceae) : questões infra-subgenéricas

Zamberlan, Priscilla Mena January 2007 (has links)
O gênero Passiflora L. (Passifloraceae) é composto por mais de 520 espécies, classificadas em quatro subgêneros: Astrophea, Decaloba, Deidamioides e Passiflora. Embora algumas análises filogenéticas tenham sido realizadas nos últimos anos, sua classificação infra-subgenérica permanece em aberto. Com o objetivo de auxiliar na elucidação destas questões e caracterizar novos marcadores filogenéticos para o gênero Passiflora, análises com seqüências do gene plastidial que codifica a maior subunidade da enzima RNA-polimerase de cloroplasto (rpoC1), dos espaçadores internos transcritos do DNA ribossomal nuclear (ITS1 e ITS2) e do íntron b-c do gene nad1 do genoma mitocondrial, foram desenvolvidas para 121 espécies de Passiflora. As análises foram realizadas usando métodos de distância, máxima parcimônia, máxima verossimilhança e inferência bayesiana para cada subgênero em separado e para o conjunto total de dados. A monofilia dos subgêneros Astrophea, Decaloba e Passiflora foi confirmada, embora a monofilia do subgênero Deidamioides permaneça em aberto. Os resultados suportam, ainda, a existência de um quinto subgênero, Tryphostemmatoides. Análises realizadas para cada subgênero em separado demonstraram que esta estratégia é um método eficiente para a análise de marcadores com alta variabilidade entre os grupos, como é o caso dos subgêneros de Passiflora. ITS1 e ITS2 foram os marcadores moleculares mais informativos. Em geral, as superseções, seções e séries dos quatro subgêneros foram não-monofiléticas, sugerindo a necessidade de uma revisão cuidadosa dos caracteres morfológicos tipicamente usados em sua delimitação. / The Passiflora L. (Passifloraceae) genus is composed of more than 520 species, classified in four subgenera: Astrophea, Decaloba, Deidamioides and Passiflora. Although some molecular phylogenetic analyses have been carried out in the last years, its infrasubgeneric classification remains open. With the intent to help to elucidate these issues and to characterize new phylogenetic markers for the Passiflora genus, analyses with sequences of the plastidial gene that codifies the biggest subunit of the RNA-polymerase enzyme of chloroplast (rpoC1), the internal transcribed spacer of nuclear ribosomal DNA (ITS1 and ITS2), and nad1 b-c intron of the mitochondrial genome have been carried out in 121 Passiflora’s species. The analyses have been conduced using distance, parsimony, maximum likelihood, and Bayesian methods for each subgenus separately and for the whole data. The Astrophea, Decaloba and Passiflora subgenera monophyly were confirmed, although the Deidamioides monophyly remains open. The results also support the existence of a fifth subgenus, Tryphostemmatoides. Separated analyses for each subgenus demonstrated to be an efficient method for analysis of markers with high variability between groups, as it is the case of the Passiflora’s subgenera. The ITS1 and ITS2 have been the more informative molecular markers. In general, the supersections, sections and series of the four subgenera were found non-monophyletic, suggesting the need of a careful revision of the morphologic characters typically used for their delimitation.
240

Retexturing the word and the world : literacy and contradiction in the texts of Paulo Freire

Taylor, P. V. January 1991 (has links)
Most studies of Freire concentrate on his method and techniques. This present work seeks to go beneath the obvious practice of Literacy teaching, to analyse the construction of his pedagogy and to explore the contradictions posed both by Freire's life (bio-texts) and by his work (grapho-texts). The study therefore proposes the most detailed Biography of Freire which is yet currently available, identifying the main stages of his career and exploring the development of his educational philosophy. Following a brief review of his Method. There is a detailed presentation of the Sources and Influences which lie behind Freire's pedagogy, which reveal his comprehensive eclecticism but which also place him firmly within the classical tradition of European education. This section reveals for the first time some of the key taproots of Freirean philosophy. This textual archaeology and genealogy is also used to construct an analysis of this philosophy through a detailed examination of the concepts of Dialogue and Conscientisation. Trying to reconcile the fundamental disjunction which appears between Freire's rhetoric and his practice. That "Dialogic Education" may be a contradiction in terms is further explored through a unique examination of the Teaching Material which Freire used in his programme. The fundamental contradiction is exposed: that Literacy, which means "learning to read" can never achieve its ideals of Dialogue. The study is itself structured on the Freirean Methodology of Coding and Decoding. In ends by placing Freire's pedagogy within the wider context (con-text) of the recent Literacy debate, confronting the nature of Literacy itself, the construction of Power and Knowledge through Writing and the further contradiction contained in the idea of "Functional Literacy". The conclusion is that Literacy is its own multi-faceted Pharmakon: of its essence, Literacy is an agent of Control and an agent of Change. The strength of the study is in its detail and in its extensive bibliographic research. It concludes that Freire's attempt to retexture Literacy, to renovate the inherent contradictions of teaching and learning, is a major contribution to Pedagogy, not because it is successful but because it authentically and exhaustively Problem Posing. The "Metodo Paulo Freire" is a contradictory pedagogy, but it is also a Pedagogy of Contradiction.

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