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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.
201

Envolvimento da neurotransmissão CRFérgica das asas laterais do núcleo dorsal da rafe na expressão de comportamentos defensivos associados ao pânico / Involvement of CRF-mediated neurotransmission in the lateral wings of the dorsal raphe nucleus in the expression of defensive behaviors associated with panic

Leonardo Daniel Mendes 21 August 2017 (has links)
O núcleo dorsal da rafe é a principal fonte de projeções serotonérgicas que inervam áreas límbicas implicadas na modulação de diferentes funções comportamentais e/ou neurovegetativas. Disfunções neste núcleo têm sido associadas à gênese de transtornos psiquiátricos. Estudos recentes apontam para a heterogeneidade morfológica e funcional do NDR, com destaque para evidências que sugerem a participação seletiva da sub-região denominada asas laterais nos mecanismos fisiopatológicos do transtorno de pânico. Dentre os diversos neurotransmissores presentes nas asas laterais, o papel desempenhado pelo fator liberador de corticotrofina (CRF) na modulação dos neurônios serotonérgicos presentes nesta área tem ganhado amplo destaque. Com base nestas evidências, o objetivo deste trabalho foi o de avaliar o envolvimento da neurotransmissão mediada pelo CRF nas asas laterais de ratos machos Wistar na expressão do comportamento de fuga avaliado no labirinto em T elevado (LTE). Os resultados obtidos mostram que administração local de CRF na dose de 100 ng atenuou a expressão do comportamento de fuga, enquanto que a dose de 0,3 ng facilitou a expressão desse comportamento, sugerindo assim um efeito do tipo panicolítico e panicogênico, respectivamente. A injeção de CRF nas asas laterais não afetou a aquisição da resposta de esquiva inibitória também medida no LTE. Este comportamento defensivo tem sido associado à ansiedade. Além disso, a administração de antalarmina, um antagonista seletivo de CRF1, previamente à dose de 0,3 ng bloqueou o efeito facilitador do CRF sobre a expressão da resposta da fuga, sugerindo então que os receptores de CRF1 estejam envolvidos no efeito panicogênico deste peptídeo. Assim sendo, o efeito do CRF sobre a resposta de fuga no LTE parece ser dependente da dose administrada. Os resultados obtidos, juntamente com dados prévios da literatura, indicam que diferentes subtipos de receptores de CRF sejam recrutados na mediação destes efeitos opostos causados pelo peptídeo. / The dorsal raphe nucleus (DRN) is the main source of serotonergic projections that innervate limbic areas involved in the modulation of different behavioral and/or neurovegetative functions. Dysfunctions in this nucleus have been associated with the genesis of psychiatric disorders. Recent studies point to the morphological and functional heterogeneity of NDR. There is evidence to suggest that the sub-region called lateral wings is involved in the physiopathological mechanisms of panic disorder. Among the several neurotransmitters present in the lateral wings, the role played by the corticotrophin releasing factor (CRF) in the modulation of the serotonergic neurons present in this area has raised attention. Based on these evidences, the objective of this work was to evaluate the involvement of CRFmediated neurotransmission in the lateral wings of male Wistar rats in the expression of the escape behavior evaluated in the elevated T maze test (ETM). The results showed that local administration of CRF at the dose of 100 ng attenuated the expression of escape behavior, whereas the dose of 0.3 ng facilitated the expression of this behavior, thus suggesting a panicolytic- and panicogenic-like effects, respectively. Injection of CRF in the lateral wings did not affect the acquisition of the inhibitory avoidance response, also measured in ETM. This defensive behavior has been associated with anxiety. In addition, the administration of antalarmine, a CRF1 receptor antagonist, prior to the 0.3 ng dose blocked the facilitatory effect of CRF on the expression of the escape response, thus suggesting that CRF1 receptors are involved in the panicogenic effect of this peptide. Thus, the effect of CRF on escape response in the ETM seems to be dose dependent. The results obtained, together with previous literature data, indicate that different subtypes of CRF receptors are recruited in the mediation of these opposite effects caused by the peptide.
202

Envolvimento da neurotransmissão CRFérgica das asas laterais do núcleo dorsal da rafe na expressão de comportamentos defensivos associados ao pânico / Involvement of CRF-mediated neurotransmission in the lateral wings of the dorsal raphe nucleus in the expression of defensive behaviors associated with panic

Mendes, Leonardo Daniel 21 August 2017 (has links)
O núcleo dorsal da rafe é a principal fonte de projeções serotonérgicas que inervam áreas límbicas implicadas na modulação de diferentes funções comportamentais e/ou neurovegetativas. Disfunções neste núcleo têm sido associadas à gênese de transtornos psiquiátricos. Estudos recentes apontam para a heterogeneidade morfológica e funcional do NDR, com destaque para evidências que sugerem a participação seletiva da sub-região denominada asas laterais nos mecanismos fisiopatológicos do transtorno de pânico. Dentre os diversos neurotransmissores presentes nas asas laterais, o papel desempenhado pelo fator liberador de corticotrofina (CRF) na modulação dos neurônios serotonérgicos presentes nesta área tem ganhado amplo destaque. Com base nestas evidências, o objetivo deste trabalho foi o de avaliar o envolvimento da neurotransmissão mediada pelo CRF nas asas laterais de ratos machos Wistar na expressão do comportamento de fuga avaliado no labirinto em T elevado (LTE). Os resultados obtidos mostram que administração local de CRF na dose de 100 ng atenuou a expressão do comportamento de fuga, enquanto que a dose de 0,3 ng facilitou a expressão desse comportamento, sugerindo assim um efeito do tipo panicolítico e panicogênico, respectivamente. A injeção de CRF nas asas laterais não afetou a aquisição da resposta de esquiva inibitória também medida no LTE. Este comportamento defensivo tem sido associado à ansiedade. Além disso, a administração de antalarmina, um antagonista seletivo de CRF1, previamente à dose de 0,3 ng bloqueou o efeito facilitador do CRF sobre a expressão da resposta da fuga, sugerindo então que os receptores de CRF1 estejam envolvidos no efeito panicogênico deste peptídeo. Assim sendo, o efeito do CRF sobre a resposta de fuga no LTE parece ser dependente da dose administrada. Os resultados obtidos, juntamente com dados prévios da literatura, indicam que diferentes subtipos de receptores de CRF sejam recrutados na mediação destes efeitos opostos causados pelo peptídeo. / The dorsal raphe nucleus (DRN) is the main source of serotonergic projections that innervate limbic areas involved in the modulation of different behavioral and/or neurovegetative functions. Dysfunctions in this nucleus have been associated with the genesis of psychiatric disorders. Recent studies point to the morphological and functional heterogeneity of NDR. There is evidence to suggest that the sub-region called lateral wings is involved in the physiopathological mechanisms of panic disorder. Among the several neurotransmitters present in the lateral wings, the role played by the corticotrophin releasing factor (CRF) in the modulation of the serotonergic neurons present in this area has raised attention. Based on these evidences, the objective of this work was to evaluate the involvement of CRFmediated neurotransmission in the lateral wings of male Wistar rats in the expression of the escape behavior evaluated in the elevated T maze test (ETM). The results showed that local administration of CRF at the dose of 100 ng attenuated the expression of escape behavior, whereas the dose of 0.3 ng facilitated the expression of this behavior, thus suggesting a panicolytic- and panicogenic-like effects, respectively. Injection of CRF in the lateral wings did not affect the acquisition of the inhibitory avoidance response, also measured in ETM. This defensive behavior has been associated with anxiety. In addition, the administration of antalarmine, a CRF1 receptor antagonist, prior to the 0.3 ng dose blocked the facilitatory effect of CRF on the expression of the escape response, thus suggesting that CRF1 receptors are involved in the panicogenic effect of this peptide. Thus, the effect of CRF on escape response in the ETM seems to be dose dependent. The results obtained, together with previous literature data, indicate that different subtypes of CRF receptors are recruited in the mediation of these opposite effects caused by the peptide.
203

Study Of Aerodynamic Effectiveness Of Wing Tip Sails For Gust Load Alleviation

Agarwal, R K 11 1900 (has links) (PDF)
No description available.
204

A Combined Piezoelectric Composite Actuator and Its Application to Wing/Blade Tips

Ha, Kwangtae 28 November 2005 (has links)
A novel combined piezoelectric-composite actuator configuration is proposed and analytically modeled in this work. The actuator is a low complexity, active compliant mechanism obtained by coupling a modified star cross sectional configuration composite beam with a helicoidal bimorph piezoelectric actuator coiled around it. This novel actuator is a good candidate as a hinge tension-torsion bar actuator for a helicopter rotor blade flap or blade tip and mirror rotational positioning. In the wing tip case, the tip deflection angle is different only according to the aerodynamic moment depending on the hinge position of the actuator along the chord and applied voltage because there is no centrifugal force. For an active blade tip subject to incompressible flow and 2D quasi steady airloads, its twist angle is related not only to aerodynamic moment and applied voltage but also to coupling terms, such as the trapeze effect and the tennis racquet effect. Results show the benefit of hinge position aft of the aerodynamic center, such that the blade tip response is amplified by airloads. Contrary to this effect, results also show that the centrifugal effects and inertial effect cause an amplitude reduction in the response. Summation of these effects determines the overall blade tip response. The results for a certain hinge position of Xh=1.5% chord aft of the quarter chord point proves that the tip deflection target design range[-2,+2] can be achieved for all pitch angle configurations chosen.
205

A small perturbation based optimization approach for the frequency placement of high aspect ratio wings

Goltsch, Mandy 26 March 2009 (has links)
Design denotes the transformation of an identified need to its physical embodiment in a traditionally iterative approach of trial and error. Conceptual design plays a prominent role but an almost infinite number of possible solutions at the outset of design necessitates fast evaluations. The traditional practice of empirical databases loses adequacy for novel concepts and an ever increasing system complexity and resource scarsity mandate new approaches to adequately capture system characteristics. Contemporary concerns in atmospheric science and homeland security created an operational need for unconventional configurations. Unmanned long endurance flight at high altitudes offers a unique showcase for the exploration of new design spaces and the incidental deficit of conceptual modeling and simulation capabilities. The present research effort evolves around the development of an efficient and accurate optimization algorithm for high aspect ratio wings subject to natural frequency constraints. Foundational corner stones are beam dimensional reduction and modal perturbation redesign. Local and global analyses inherent to the former suggest corresponding levels of local and global optimization. The present approach departs from this suggestion. It introduces local level surrogate models to capacitate a methodology that consists of multi level analyses feeding into a single level optimization. The innovative heart of the new algorithm originates in small perturbation theory. A sequence of small perturbation solutions allows the optimizer to make incremental movements within the design space. It enables a directed search that is free of costly gradients. System matrices are decomposed based on a Timoshenko stiffness effect separation. The formulation of respective linear changes falls back on surrogate models that approximate cross sectional properties. Corresponding functional responses are readily available. Their direct use by the small perturbation based optimizer ensures constitutive laws and eliminates a previously necessary optimization at the local level. The great economy of the developed algorithm makes it suitable for the conceptual phase of aircraft design.
206

Conceptual study of rotary-wing microrobotics

Chabak, Kelson D. January 2008 (has links)
Thesis (M.S.)--Air Force Institute of Technology, 2008. / Title from title page of PDF document (viewed on: Dec 10, 2009).
207

Educação do campo e da floresta: um olhar sobre a formação docente no Programa Asas da Florestania no alto Juruá/AC

Souza, José Valderí Farias de 17 June 2013 (has links)
Made available in DSpace on 2015-04-22T21:55:36Z (GMT). No. of bitstreams: 1 Jose Valderi Farias de Souza.pdf: 2132621 bytes, checksum: 64271b9a914d88cb62810687314cae30 (MD5) Previous issue date: 2013-06-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation - Education in Rural and Forest: a look at teacher education program in the Wings of Florestania the upper Juruá / AC - had at analyzing and understanding of the project education that has been developed in Cruzeiro do Sul / Acre more specifically in the city of Cruzeiro do Sul, the Program " Wings Forestania" in view of the continuing education of teachers in the field and the forest, in order to understand if and in what ways, its proposal is consistent with the emancipatory perspective of education field / forest / river and what knowledge being valued in the continuing education of teachers. Besides trying to identify new paradigms regarding teacher training in the forest, in valuing the knowledge challenges and struggles of the field, this proposal is put on the agenda of the major debates of inclusive policies. To develop this research, we adopted the methodology of field research, qualitative in nature, whose instruments of data collection were: direct contact, technical literature and semi-structured interviews. The subjects in this investigation were heard: Ten educators / the two regional coordinators and general coordinator of the program. Through the procedures used in the data analysis, theoretically subsidized by authors of reference, one can see the strong influence and imposition of the forest, the hegemonic capitalist state model, based on the urban / rural dichotomy and imposing educational models with heavy load discriminatory against constructed knowledge in the field / forest. It was noticed, however, that in the last two decades, the education field has managed to introduce its uniqueness, from the conception that we live in a multicultural country, heterogeneous, where people got different looks and ways to express your thinking, their understanding of the world. In this sense, the research is constituted as a possible way of producing knowledge, recognizing the heterogeneity and the need for establishment of other resumes and other pedagogies, those who are able to listen to the voices and secure seat to the men and women of the forest in decisions and discussions that interest them. The research advocates the construction of the field school is vested in social movements, it is able to respond to new challenges, tensions and contradictions present in the field / forest, able to raise the critical consciousness of the workers. / Esta dissertação - Educação do Campo e da Floresta: um olhar sobre a formação docente no Programa Asas da Florestania no Alto Juruá/AC - teve como objeto analisar e compreender um projeto de educação da floresta que vem sendo desenvolvido na região do Alto Juruá/Acre, mais especificamente na cidade de Cruzeiro do Sul, pelo Programa Asas da Florestania, na perspectiva da formação continuada de professores do campo e da floresta, no sentido de compreender, se e em que aspectos, sua proposta é coerente com a perspectiva emancipatória da educação do campo/da floresta/ribeirinha e quais os saberes que estão sendo valorizados na formação continuada de professores. Além de tentar apontar novos paradigmas a respeito da formação docente na floresta, desafios na valorização dos saberes e das lutas do campo, essa proposta se coloca na pauta das grandes discussões de políticas inclusivas. Para desenvolver esta investigação, adotou-se a metodologia da pesquisa de campo, de natureza qualitativa, cujos instrumentos de coleta de dados foram: contato direto, pesquisa bibliográfica e a técnica de entrevistas semiestruturadas. Os sujeitos ouvidos nesta investigação foram: dez educadores/as, duas coordenadoras regionais e a coordenadora geral do Programa. Por meio dos procedimentos adotados na análise dos dados, teoricamente subsidiada por autores de referência, pode-se perceber a forte influência e imposição à floresta, do modelo estatal hegemônico capitalista, pautado na dicotomia urbano/rural e na imposição de modelos educacionais com forte carga discriminatória frente aos saberes construídos no campo/floresta. Percebeu-se, porém, que nas últimas duas décadas, a educação do campo tem conseguido se apresentar em sua singularidade, a partir da concepção de que se vive em um país multicultural, heterogêneo, onde o povo adquiriu diferentes jeitos e olhares de manifestar seu pensamento, sua compreensão de mundo. Nesse sentido, a pesquisa se constitui como uma das formas possíveis de produzir conhecimento, reconhecendo a heterogeneidade e a necessidade de constituição de outros currículos e outras pedagogias, aquelas que sejam capazes de auscultar as vozes e garantir assento aos homens e às mulheres da floresta nas decisões e debates que lhes interessa. A pesquisa propugna pela construção da escola do campo ensejada nos movimentos sociais, que seja capaz de responder aos novos desafios, tensões e contradições presentes no campo/floresta, capaz de elevar a consciência crítica dos trabalhadores e trabalhadoras.
208

Občanská angažovanost očima členů mládežnických organizací politických stran / Civic engagement through the eyes of members of political parties youth wings

Vachule, Filip January 2015 (has links)
The theme of my thesis is "Civic engagement though the eyes of political parties youth wings." I chose three specific associations, which cover the classical political spectrum. The goal of the thesis is to discover what kind of relationship these young people have to civic engagement. Civic engagement is represented by the new type of engaged NGOs. I also wanted to know what was their motivation to join the youth wing and if their opinions about civic engagement corespond with the Party point of view. In the theoretical part I introduce concepts of political participation and civic engagemant connected with the third sector and political parties. In the empirical part is presented the analysis with the findings. I used qualitative research strategy and data were obtained mostly trom interviews. In the end the findings are summarized and connscted with the theoretical framework.
209

Evolution and phylogeny of basal winged insects with emphasis on mayflies (Ephemeroptera)

Ogden, Thomas H. 29 November 2004 (has links) (PDF)
Ephemeroptera (mayflies) is a monophyletic group of semi-aquatic pterygote insects, comprising 3083 species, 376 genera, and 37 described families and are present on all continents, excluding Antarctica, being associated with freshwater and brackish water habitats. The order is unique among pterygote insects in possessing functional wings at the penultimate molt (subimago stage), prior to the full development of genitalia; in all other insects the presence of functional wings occurs only after the final molt. The purpose of this dissertation is to use molecular and morphological data, in order to investigate the position of the order Ephemeroptera among other insect orders, the higher-level relationships among the major lineages of mayflies, and a detailed analysis of the family Ephemerellidae. Ephemeroptera has been considered by many to be sister to Odonata + Neoptera although alternate hypotheses have been suggested. Data from three molecular loci ambiguously resolve basal pterygote relationships, however, total evidence analysis (combined molecular and morphological data) strongly supports the position of mayflies as sister to all other extant pterygotes. These results and methodologies were recently criticized, and, therefore, the response to the author is included following the manuscript. The phylogenetic relationships among mayfly families is debatable and in some groups unknown. Prior studies have produced phylogenies based on morphological characters mixed with intuition. The first molecular phylogeny for the Order Ephemeroptera is presented. The analyses include 31 of the 37 families, representing ~24% of the genera. The suborders Furcatergalia and Carapacea are supported as monophyletic while Setisura and Pisciforma are not supported as monophyletic. The evolution of the wings, mandibular tusks, burrowing lifestyle, and fishlike body are investigated. Topological sensitivity analysis is used as a tool to examine patterns concerning the stability of relationships across a parameter landscape, providing additional information that may not have been acquired otherwise. The Pannote family Ephemerellidae is comprised of 16 genera and over 300 species and is distinguished from other mayfly families by the absence of the second pair of abdominal gills. The position of Ephemerellidae relative to other closely related pannote mayflies is unclear as are the relationships of the genera within the family. The combined molecular and morphological analyses resulted in a monophyletic Ephemerellidae as sister to the other ephemerelloid families. The subfamily Ephemerellidae was supported as monophyletic, while Timpanoginae had conflicting results.
210

Representation of Gender, Ethnicity and Sexuality in Wings 7, 8 and 9

Nilsson, Magnus January 2009 (has links)
Textboken är en nyckelkomponent i engelsklärarens arsenal. Av den anledningen är det viktigt att boken överensstämmer med värdegrunden när det gäller ett flertal frågor. Vad denna uppsats ämnar göra är att analysera några böcker i Wings-serien, som är en populär skolboksserie som används i Sverige. Studien fokuserar på de böcker som används i grundskolans senare del och den inkluderar både Base Book och Activity Book för Wings 7, 8 och 9. Undersökningen görs genom att studera tre ämnesområden, nämligen genus, etnicitet och sexualitet. Dessa tre områden har studerats med avsikten att identifiera ideologier och exempel på representation som är kopplade till dessa områden. Analysens resultat i avseende på både representation och ideologier visar att Wings återger en bred och ickestereotypisk bild av könsroller som överensstämmer med värdegrunden. Medan genus visas som ett positivt exempel på hur modernt tänkande är synligt i böckerna, så stämmer detta inte fullständigt med avseende på etnicitet och sexualitet. Resultaten visar att representation av etnicitet, i avseende på hudfärg, är mycket lik den bild som har kunnat observeras i böcker som använts så långt tillbaka som 1965. I kontrast till detta så visas dock religion och social klass på ett balanserat och modernt sätt.Sexualitet är mer komplext avbildat och även om heterosexualitet visas på ett balanserat sätt så finns praktiskt taget inga spår av vare sig homo eller bisexualitet. / The text book is a key component in the arsenal of a teacher of English. For this reason, it is important that this book agrees with the Fundamental Values, when it comes to numerous issues. What this essay seeks to do is to analyze some books in Wings, which is a popular series of schoolbooks used in Sweden. This study focuses on the books that are used at secondary school and includes both the Base Book and the Activity Book for Wings 7, 8 and 9. The investigation is done by studying three topic areas, namely: gender, ethnicity and sexuality. These areas are investigated with the intention of identifying ideologies and examples of representation that connect to these areas. The findings from the analysis of both ideologies and the examples of representation show that Wings gives a broad and non-stereotypic view of gender roles which is in accordance with the fundamental values. While gender is a positive example of how modern thinking is visible in the books, the same does not completely apply to ethnicity and sexuality. Findings indicate that representation of ethnicity in Wings, when focus is placed on skin-color, is very similar to that which was observed in books used as far back as 1965. In contrast, religion and class are portrayed in a more balanced and modern manner. Sexuality is depicted in a more complex way and while the books show a balanced view of heterosexuality, virtually no mention of homo/bisexuality can be found.

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