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Ernst, Stephanie. "Ahas, König von Juda : ein Beitrag zur Literatur und Geschichte des Alten Israel /." St. Ottilien : EOS Verl, 2006. http://catalogue.bnf.fr/ark:/12148/cb41111077t.
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Vargas, Leandro. "Resistência de Euphorbia heterophylla L. aos herbicidas inibidores da enzima acetolactato sintase (ALS/AHAS)." Universidade Federal de Viçosa, 2000. http://www.locus.ufv.br/handle/123456789/10149.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A ocorrência de plantas daninhas resistentes a herbicidas é um fato novo no Brasil. A caracterização da resistência é importante para embasar previsões e eleger métodos de manejo e controle. Desse modo, foram realizados na Universidade Federal de Viçosa, de março de 1997 a julho de 1999, quatro experimentos, objetivando de identificar biótipos resistentes e caracterizar a resistência. O primeiro experimento objetivou identificar e estudar os mecanismos envolvidos na resistência, cujos resultados indicaram resistência cruzada aos herbicidas inibidores da enzima ALS. Estudos com ALS, extraída de plantas resistentes de leiteiro, indicaram I50 superior a 3.000 μM para o imazapyr e 2.000 μM para o imazethapyr, contrastando com valores de I50 de 2 μM para aquele e 0,7 μM para este em plantas sensíveis. No segundo experimento, investigou-se a resposta dos biótipos resistentes a herbicidas com diferentes mecanismos de ação. Constatou-se que os herbicidas inibidores da ALS controlaram com eficiência o biótipo sensível, à exceção do flumetsulan; já sobre o biótipo resistente, somente o herbicida imazapyr, na maior dose, apresentou controle. Os herbicidas com mecanismos de ação distintos daqueles dos inibidores da ALS apresentaram-se altamente eficientes no controle dos biótipos resistentes e sensíveis quando aplicados de forma isolada ou em mistura. O terceiro experimento objetivou descrever uma técnica de cruzamento controlado em Euphorbia heterophylla L. Os resultados evidenciaram que as polinizações e emasculações realizadas no estádio 1 produzem grande número de ciátios com uma ou duas sementes e raramente com três. As realizadas no estádio 2, ou acima deste, garantiram o sucesso dos cruzamentos com boa produção de sementes. No quarto experimento, estudaram-se a herança, o número de genes que conferem a resistência e o grau de resistência dos biótipos homozigotos e heterozigotos resistentes. As plantas F1 mostraram-se totalmente resistentes ao herbicida, indicando que a resistência é nuclear e dominante. As plantas F2 apresentaram alta probabilidade para segregação 3:1, evidenciando que a resistência é codificada por um gene dominante. Pela aplicação de doses crescentes de imazethapyr sobre as plantas F1, calculou-se que os biótipos homozigotos resistentes e os heterozigotos apresentaram o mesmo grau de resistência para doses de até 1.600 g ha-1 desse herbicida. Os resultados permitiram concluir que a insensibilidade da enzima ALS aos herbicidas que a inibem é o principal mecanismo responsável pela resistência das plantas de Euphorbia heterophylla L. a tais produtos. Os biótipos resistentes são controlados com eficiência com herbicidas com mecanismos de ação distintos daqueles dos inibidores da ALS. A resistência é codificada por um gene dominante nuclear com dominância completa.
The occurrence of herbicide-resistant weeds is a new fact in Brazil. The characterization of the resistance is important to provide a base for previsions and select methods of management and control. Therefore, four experiments were carried out at the Universidade Federal de Viçosa, from March,1997, to July, 1999, to identify resistant biotypes and to study the mechanisms involved in resistance. The first experiment, aimed to identify and study the mechanisms involved in the resistance, had the results indicating cross resistance to ALS inhibitory herbicides. Studies with ALS, extracted from resistant plants, showed l50 superior to 3000 μM for imazapyr and 2000 μM for imazethapyr, which contrasted with l50 values of 2 μM for the former and 0.7 μM for the latter in susceptible plants. The second experiment analyzed the response of the resistant biotypes to herbicides with different modes of action. It was verified that the ALS inhibitory herbicides had efficient control over the susceptible biotypes, apart from flumetsulan; as for the resistant biotype, only the herbicide imazapyr at its highest dose, showed control. The herbicides with modes of action distinct from those ALS inhibitors were shown highly efficient on controlling susceptible and resistant biotypes when applied separately or in mixture. The third experiment aimed to describe a technique of controlled crossings in Euphorbia heterophylla L. The results showed evidence that pollination and emasculation performed at stage 1 produce a great number of ciatios with one or two seeds and rarely with three. Those performed at stage 2, or above this stage, assured the success of the crossings with a good production of seeds. In the fourth experiment, the inheritance, the number of genes that confer resistance and the degree of resistance in resistant homozygote and heterozygote biotypes, were studied. The F1 plants were shown totally resistant to the herbicide, indicating that the resistance is nuclear and dominant. The F2 plants presented a high probability for 3:1 segregation, making evident that the resistance is codified by a dominant gene. It was calculated that the biotypes resistant homozygote and heterozygote showed the -1 same degree of resistance for doses up to 1600 g ha , by means of the application of increasing doses of imazethapyr on F1 plants. The results obtained permit the conclusion that the insensitivity of the ALS enzyme to the herbicides is the primary mechanism responsible for the resistance of Euphorbia heterophylla L. to such products. The resistant biotypes are efficiently controlled by herbicides with mechanism of action distinct from those of the ALS inhibitors. The resistance is codified by a nuclear dominant gene with complete dominance.
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Friesen, Lincoln Jacob Shane. "Identification of the mechanisms of wild radish herbicide resistance to PSII inhibitors, auxinics, and AHAS inhibitors." University of Western Australia. School of Plant Biology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0106.
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The objective of this Ph.D. research was to identify new and novel mechanisms of wild radish (Raphanus raphanistrum L.) resistance to photosystem II (PSII) inhibitors, auxinics, and acetohydroxyacid synthase (AHAS) inhibitors. PSIIinhibitor resistance was demonstrated to be target-site based, and conferred by a Ser264 to Gly substitution of the D1 protein. Auxinic resistance was associated with reduced herbicide translocation to the meristematic regions of resistant wild radish plants. Two new resistance mutations of wild radish AHAS were discovered, including one encoding the globally rare Asp376 to Glu substitution, and another encoding an Ala122 to Tyr substitution, which has never been identified or assessed for resistance in plants previously. Characterization of the frequency and distribution of AHAS resistance mutations in wild radish from the WA wheatbelt revealed that Glu376 was widespread, and that some mutations of AHAS are more common than others. Computer simulation was used to examine the molecular basis of resistance-endowing AHAS target-site mutations. Furthermore, through the computer-aided analysis, residues were identified with the potential to confer resistance upon substitution, but which have not previously been assessed for this possibility. Results from this Ph.D. research demonstrate that diverse, unrelated mechanisms of resistance to PSII inhibitors, auxinics, and AHAS inhibitors have evolved in wild radish of the WA wheatbelt, and that these mechanisms have accumulated in some populations.
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Silva, Viviane Aparecida. "Estudo, por modelagem molecular, da inibição da enzima acetohidroxiácido sintase utilizando diferentes derivados pirimidinilsalicilatos." Universidade Federal de Uberlândia, 2017. http://dx.doi.org/10.14393/ufu.di.2018.94.
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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorHerbicides inhibitors of the enzyme acetohydroxyacid synthase (AHAS) present high efficiency in the inhibitory activity with low doses of application and low toxicity for man and the environment. However, several weeds are getting resistence to some classes of herbicides, mainly in the case of AHAS group. Therefore, a proper computational planning of new bioactive compounds is crucial area to model new herbicides. In this study, the enzyme-herbicide interactions were analyzed from the analogous derivated of the pyrimidinylsalicylates group (PSA) which are AHAS inhibitors using quantum- mechanical and molecular docking calculations. The molecular properties obtained after running computer calculation shown that the volume and molecular area can make influence on the inhibition capacity of the ligand, neverthenless, the substituent group has more influence on this parameter. Electronical properties from the HOMO orbitals can certanly make influence on the biological activity due its electron donor capability. The binding free energies of the ligand on the enzyme after docking calculation ranged from - 1.88 to 4.50 kcal mol- 1 , whereas, H, CH3, COCH3 , OH, NO2 and NH2 had the best scored binding energies as substituent groups. Those favorable binding free energies can be justified by the intermolecular interactions between PSAs ligands and AHAS active site residues. In terms of effiency, hydrogen bonds formation can be explained by carboxylate group from the ligands and ARG-377 group from AHAS.
Os herbicidas inibidores da enzima acetohidroxiácido sintase (AHAS) apresentam alta eficiência na atividade inibitória com baixas doses de aplicação com baixa toxicidade para o homem e o meio ambiente. No entanto, várias ervas daninhas estão obtendo resistência a algumas classes de herbicidas, principalmente no caso do grupo AHAS. Portanto, um planejamento computacional adequado de novos compostos bioativos é área crucial para modelar novos herbicidas. Neste estudo, as interações enzima-herbicida foram analisadas a partir do derivado análogo do grupo pirimidinilsalicilato (PSA) que são inibidores de AHAS usando cálculos mecânicoquânticos e de docking molecular. As propriedades moleculares obtidas mostraram que o volume e a área molecular podem influenciar a capacidade de inibição do ligante, mesmo que o grupo substituinte tenha mais influência sobre este parâmetro. As propriedades eletrônicas dos orbitais HOMO podem certamente influenciar a atividade biológica devido à sua capacidade de doação de elétrons. As energias livres de ligação do ligante na enzima após o cálculo de docking variaram de -1,88 a - 4,50 kcal mol- 1 , enquanto que H, CH3, COCH3, OH, NO2 e NH2 apresentaram as melhores energias de ligação pontuadas como grupos substituintes. Estas energias livres de ligação favoráveis podem ser justificadas pelas interações intermoleculares entre ligantes de PSAs e resíduos de sítio ativo de AHAS. Em termos de eficiência, a formação de ligações de hidrogênio pode ser explicada pelo grupo carboxilato partir dos ligantes e do grupo ARG-377 de AHAS.
Dissertação (Mestrado)
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Rose, Sophie. "Optimisation de la prolifération et de la différenciation des hépatocytes humains dans un nouveau modèle de culture 3D : application à l'étude des Amines Hétérocycliques Aromatiques (AHAs)." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B022.
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Le foie joue un rôle prépondérant dans la biotransformation et l’élimination des xénobiotiques. Le développement de modèles cellulaires hépatiques humains pertinents représente un enjeu majeur afin d’étudier in vitro chez l’Homme la bioactivation de contaminants préoccupants, les altérations à l’ADN qui en dérivent et leur pouvoir mutagène/cancérigène. Ces analyses constituent des étapes clés pour l’identification de biomarqueurs d’exposition indispensables à l’évaluation du risque au niveau des individus et dans les populations. Lors de cette thèse, nous avons mis au point un modèle original de culture 3D en gels de collagène dans lequel les hépatocytes humains s’organisent en sphéroïdes polarisés. Par cette approche, nous avons démontré, pour la première fois, la capacité des hépatocytes primaires cultivés en 3D à proliférer in vitro. De plus, une réinitialisation du cycle cellulaire peut être obtenue après l’inhibition transitoire de la voie de signalisation des MAPKs MEK1/2-ERK1/2. Dans nos conditions, les hépatocytes primaires et transformés expriment des fonctions hépatiques hautement différenciées pendant plusieurs semaines de culture, et les cellules HepaRG se différencient après seulement quelques jours de culture, sans ajout de DMSO. Dans ce contexte, nous avons étudié la génotoxicité d’une classe de contaminants de l’environnement et de l’alimentation, les Amines Hétérocycliques Aromatiques (AHAs). Nos résultats démontrent la pertinence de la culture cellulaire en gels de collagène pour l’identification et la quantification des adduits à l’ADN et les études de toxicité aiguë et chronique dans les hépatocytes humains. Ces travaux représentent une avancée majeure car ils lèvent un verrou au développement de nombreuses applications biotechnologiques. L’établissement de tels modèles d’hépatocytes humains proliférants in vitro permet d’évaluer le pouvoir mutagène des contaminants de l’environnementThe liver plays a major role in metabolism and elimination of xenobiotics. The development of relevant human in vitro models represents a major challenge to study the hepatic bioactivation of drugs and contaminants, the DNA alterations and their mutagenic/carcinogenic potential. These analyzes are key steps for identifying biomarkers of exposure that are essential for assessing risk in populations. In this study, we developed an original cellular model of 3D culture in collagen gels in which human hepatocytes are well organized in spheroids with an apico-basal polarity. By this approach, we demonstrated, for the first time, the ability of these 3D primary human hepatocytes to proliferate in vitro. Furthermore, a new cell cycle can be reinitiate after transient MAPKs MEK1/2-ERK1/2 signaling pathway inhibition. Under our conditions, primary and transformed hepatocytes express highly differentiated hepatic functions for several weeks of culture, and HepaRG cells differentiate after only few days of culture without addition of DMSO. In this context, we investigated the genotoxicity of a class of environmental and food contaminants, the Heterocyclic Aromatic Amines (HAA). Our results demonstrate the relevance of the collagen gel culture for the identification and quantification of DNA adducts and for acute and chronic toxicity studies in human hepatocytes. This work provides long-awaited keys for further biotechnological promising developments. Such establishment of in vitro proliferating human hepatocytes models will enable the evaluation of the mutagenic potential of environmental contaminants
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Ganeshan, Dharshini. "Cell selection, characterization and regeneration of chlorsulfuron-resistant variants in asparagus." Lincoln University, 1999. http://hdl.handle.net/10182/1871.
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This thesis reports the cell culture establishment and a somatic cell selection system optimized for the isolation of chlorsulfuron-resistant variants in asparagus (Asparagus officinalis L.). The development of this cell selection system benefited the isolation of chlorsulfuron-resistant variants from an elite asparagus genotype. A cell culture system, suitable for somatic cell selection, was established for asparagus genotype CRD 168. Friable callus was initiated from etiolated shoots in darkness and used to produce a high density of single cells in suspension. Cell density was estimated based on a linear relationship with settled cell volume. A mean plating efficiency of 0.19 % was recorded between 1-4x10⁵ cells/Petri dish. In vitro cell selection techniques were developed to identify mutant asparagus cells with resistance to a sulfonylurea herbicide, chlorsulfuron. A few key aspects were important to achieve this: a cell culture system for cell selection was initially established; a toxic concentration for the complete growth inhibition of the wild type asparagus cells was defined; rare, resistant cell colonies were isolated and characterized; and chlorsulfuron-resistant plants were regenerated. From about 50 million cells, 165 cell colonies were isolated in the presence of 8 nM chlorsulfuron. Characterization of these selected cell colonies yielded 24 escapes, 98 unstable variants, and 43 stable-resistant variants. Callus cultures from 34 of these stable variants retained resistance following 11 months growth in the absence of the selection agent. Plants were regenerated from 36 of these stable herbicide-resistant variants. Six of these chlorsulfuron-resistant variants were screened for their degree of resistance to chlorsulfuron, cross resistance to other acetohydroxyacid synthase (AHAS) inhibiting herbicides and AHAS enzyme activity. Cross resistance to imazamox was evident in four of the resistant variants, while lack of cross resistance to metsulfuron methyl was observed in all six resistant variants. A varying degree of resistance to chlorsulfuron was observed among the resistant variants. Both in the original and secondary callus, an uninhibited AHAS enzyme activity in all six resistant variants was recorded in the presence of high chlorsulfuron concentration (70-140 nM), compared to the total inhibition in the wild type. One chlorsulfuron-resistant variant, R-45, was used to compare the biochemical and physiological basis of resistance with the wild type. The AHAS enzyme activity in the tissue culture and greenhouse foliage of R-45 was significantly higher in the presence of up to 280 nM chlorsulfuron compared with the wild type. Chlorsulfuron retention was considerably higher due to the reduction of epicuticular wax deposits on the foliage of R-45, in comparison with the wild type. Consequently, the resistant line absorbed at least 1.6 fold more chlorsulfuron than the wild type plants. Therefore, foliar application of 15 g a.i./ha Glean (commercial formulation of chlorsulfuron) produced typical symptoms of chlorosis in R-45, similar to the wild type, in the greenhouse plants. Somatic cell selection was carried out using two elite asparagus genotypes, CRD 74 and Clone X. Of the 33 rare cell colonies isolated from Clone X, 22 unstable variants and 6 escapes were discarded. All five remaining resistant variants produced plants. One of the stable-resistant variants (Clone X-24) was evaluated for resistance to chlorsulfuron. Both in vitro shoot cultures and greenhouse-grown plants of Clone X-24 showed increased resistance to chlorsulfuron compared with the wild type. The AHAS enzyme activity in the foliar extracts also showed the presence of higher enzyme activity in Clone X-24.
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Degrande, Delphine. "Etude de l'expression de l'acétohydroxyacide synthase (AHAS) au cours du cycle de développement de la chicorée Witloof (Cichorium intybus L. ) et effets de l'apport exogène de valine chez la chicorée et Aradopsis Thaliana." Lille 1, 2000. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2000/50376-2000-240.pdf.
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Notre etude a d'abord porte sur l'expression de l'acetohydroxyacide synthase (ahas, ec 4. 1. 3. 18) qui est la premiere enzyme commune a la biosynthese de la valine, la leucine et isoleucine. Cette etude a ete realisee chez la chicoree witloof (cichorium intybus l. ) Au cours de son cycle de developpement, ainsi que pendant le forcage de sa racine tuberisee lors de la production d'endive. Le gene de l'ahas peut etre assimile a un gene de menage car il s'exprime dans la plupart des organes. Cependant son expression est plus importante dans les organes en croissance active et les organes inflorescentiels. La racine tuberisee, quant a elle, ne presente aucune expression. Ainsi, la mise en place de la tuberisation participerait a la diminution de l'expression de l'ahas observee dans la racine au cours du developpement des plantules. Ensuite nous nous sommes interesses aux effets de l'apport exogene de valine, connue pour exercer une retroinhibition allosterique de l'ahas, parallelement chez de jeunes plantules de chicoree et d'arabidopsis thaliana. Il en resulte une inhibition reversible de la croissance. En particulier, la structure histologique de la racine est fortement alteree aussi bien dans la partie basale qu'apicale. L'apparition d'-aminobutyrate non detectable dans les plantes temoin reflete l'inhibition de l'ahas. Celle-ci s'effectue sans modification de l'expression du gene codant pour l'ahas et s'accompagne d'une augmentation de la teneur en acides amines libres. Ceux-ci ne proviennent pas de la surexpression d'enzymes impliquees dans l'assimilation azotee, la nitrate reductase et la glutamine synthetase. Un apport de valine durant quelques jours montre qu'elle est absorbee rapidement et provoque l'inhibition precoce de l'ahas chez les deux especes.
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Dively, Ronda S. "Empathy for Captain Ahab /." View online, 1989. http://repository.eiu.edu/theses/docs/32211131012518.pdf.
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Bugay, Edson Luiz. "O modelo AHAM - MI." Florianópolis, SC, 2006. http://repositorio.ufsc.br/xmlui/handle/123456789/88215.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.Made available in DSpace on 2012-10-22T06:41:26Z (GMT). No. of bitstreams: 1 225285.pdf: 2626044 bytes, checksum: f9e6c6cf997573aff5a8ed24896f5144 (MD5)
A utilização da hipermídia vem se tornando cada vez mais acessível e popular ao público em geral nas mais diversas áreas, tais como lazer, marketing, comércio eletrônico e principalmente no ensino onde ela permite ao usuário a exploração livre dos materiais apresentados através de diversas mídias estruturadas por links. Além de fornecer o material didático, proporciona uma forma de navegação onde o controle da interação está totalmente a cargo do usuário, permitindo que este tenha progresso de acordo com os seus interesses e objetivos e em seu próprio ritmo, sendo esta a principal característica pedagógica. De outro lado a Hipermídia Adaptativa estuda o desenvolvimento de sistemas capazes de promover a adaptação de conteúdos e recursos hipermídia vindos de qualquer fonte (bancos de dados, Internet, serviços, etc.) e apresentados em qualquer formato (texto, áudio, vídeo, etc e suas combinações) de forma individualizada a cada usuário, baseado em suas características individuais representadas em um Modelo do Usuário. O modelo AHAM-MI, proposto neste trabalho, utilizou os conceitos de regras "pedagógicas" introduzidas por Wu, Houben e De Bra no modelo AHAM, a estrutura do modelo Munich de Koch e Wirsing e acrescentou os conceitos das Inteligências Múltiplas de Gardner em seu Modelo de Adaptação e o Modelo do Usuário. No AHAM-MI, o Modelo de Adaptação seleciona o conteúdo a ser apresentado levando em conta o conhecimento do usuário sobre o assunto (como os demais sistemas existentes) e utilizando também o desenvolvimento das suas inteligências (de acordo com Gardner) para influir na adaptação, de modo que o aprendizado ocorra de acordo com as necessidades deste usuário. A base dos Sistemas de Hipermídia Adaptativa é o Modelo do Usuário onde são armazenados todas as características e o conhecimento de cada um dos usuários. No AHAM-MI, também será armazenado o nível de desenvolvimento de cada uma de suas inteligências, o que vem de encontro com a visão de uma escola ideal de Gardner como o lugar onde estudantes, de forma individual, terão suas inteligências reconhecidas e sua evolução será avaliada no contexto destas inteligências. The hypermedia's application is more and more accessible and popular to the general public in different areas like recreation, marketing, E-commerce and especially for learning, where it allows the user the free exploration of the contents through several kinds of media organized by links. Besides providing the scholastic material, it provides a kind of navigation where the interactive control is up to the user, allowing his/her progress according to his/ her own interests, objectives, and rhythm, this being the main pedagogic characteristic. On the other hand, Adaptive Hypermedia studies the development of systems capable of promoting the adaptation of contents and hypermedia resources from any source (data banks, Internet, services, etc) and presented in any format (text, audio, video, etc, and its combinations) in an individualized way for each user, based upon his/her individual characteristics represented by an User Model. The AHAM-MI model, proposed on this work, has taken advantage of the concept of "pedagogical" rules proposed by Wu, Houben and De Bra in the AHAM model, the Koch's and Wirsing's Munich model's structure and added Gardner's Multiple Intelligence concepts in the Adaptation Model and the User Model. On the AHAM-MI the Adaptation Model select the content to be presented taking into account the user's knowledge about this subject (as do other existing systems) and also the development of each of his/ her diverse intelligences (according to Gardner) to influence the adaptation, so that the learning takes place according to the user's necessities. The Adaptative Hypermedia Systems base is the User Model where all users' characteristics and knowledge are stored. On AHAM-MI, the development level of each intelligence also will be stored, which is the Gardner's vision of the ideal school as a place where students have their intelligences recognized individually and where their evolution is evaluated considering those intelligences.
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Groseclose, Adam Richard. "Forming of AHSS using Servo-Presses." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1408548321.
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Siridhara, Siradol. "AHS Maglev System Architecture." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/29219.
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In the period between 1993-1998 a vision was presented of an Automated Highway System developed under a contract naming Virginia Tech one of the three ITS Research Centers of Excellence in the United States by the Federal Highway Administration. The AHS envisioned would consist of a guideway constructed in the rights-of-way of the Interstate Highway System which would utilized magnetic levitation ("maglev") to propel closely-space, individual vehicles at high speeds with full longitudinal and lateral control. In this dissertation the system architecture is described in detail.
The system architecture is organized according to system structural, system operational, and vehicle subsystem technological elements. The structural aspects are concerned with the decision making capability allocated between a vehicle and the guideway, the characteristics of the control and sensing equipment contained within the guideway, the traveling unit configuration, and certain of the vehicle's structural and equipment considerations. The operational aspects are concerned with vehicle entrainment policy, system fleet mixture, network type and control functions, and guideway lane separation requirements. The vehicle subsystem and the vehicle longitudinal and lateral control subsystem.
The operational architecture concentrates on developing and evaluating strategies for forming platoons of vehicles on the guideway since the average platoon sizes determine the practical capacity of the guideway as well as the safety of operation. It is instructive to review how platoons form naturally on conventional highways as a prelude to developing a strategy for forming platoon on the AHS Maglev Guideway. A novel, non-linear car-following model called "car maneuvering" is explored by defining the stimuli on the right-hand side of the model in terms of several vehicles ahead of the response vehicle. In order to add still more realism in developing a strategy for platoon formation in a guideway under automatic control, an additional spacing dependent term is introduced to achieve a "magnetic coupling headway" between platooned vehicles. Once vehicles are magnetically coupled, the desired intraplatoon headway is maintained through attraction and repulsion.
In this dissertation the term "architecture" is interpreted in the broadest possible sense based on the assumption that any transportation system intended to serve society throughout the 21st Century and beyond must address a hierarchy of goals and issues ranging from the strategic (sustainable development) to the tactical (the concept of operations) and including the in-between (interfacing with the existing transportation system). In the past, transportation planning, policy, investment and operating decisions have been made in isolation from each other with incomplete information inputs from a broad base of disciplines and sectors, without a synthesizing instrumentality. A new approach is described to promote the best informed decisions governing planning and management. The approach features a realistic framework for allocating public sector-private sector effort, an instrumentality for generating the knowledge needed to conceive and implement the new transportation paradigm, and a strategic vision for rallying support.
The new approach to the problem begins with a strategic vision for society's AHS infrastructure. We believe that the strategic vision must be based on the concept of "sustainable development." To affect this new strategic vision, higher budgets will be a necessary, but not a sufficient condition. A fundamental Decision Support System (DSS) with knowledge bases with contributions from the braid spectrum of science and engineering disciplines, and a methodology based on system dynamics capable of synthesizing these contributions is proposed.
The AHS Maglev Alternative is compared to a "Do-Nothing" Alternative and a "Traditional Expansion" Alternative using user and nonuser benefit analyses. The advantages of AHS Maglev are seen to be overwhelming. Moreover, the ability of AHS Maglev to alleviate airport congestion by reducing short and medium range of flights, and to serve as a structuring device for rational population distribution is shown.Ph. D.
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Aviv, Aviva. "Ahad Ha-Am's concept of Jewish nationalism." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359620.
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Slikker, Hank B. "Narrative art, unity, and theology in 1 Kings 22:1-38." Theological Research Exchange Network (TREN), 1991. http://www.tren.com.
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Kershner, Kellan Scott. "Herbicide resistance in grain sorghum." Diss., Kansas State University, 2010. http://hdl.handle.net/2097/13069.
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Doctor of PhilosophyDepartment of Agronomy
Kassim Al-Khatib
Mitchell R. Tuinstra
Sorghum acreage is declining throughout the United States because management options and yield have not maintained pace with maize improvements. The most extreme difference has been the absence of herbicide technology development for sorghum over the past twenty years. The objectives of this study were to evaluate the level of resistance, type of inheritance, and causal mutation of wild sorghums that are resistant to either acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides or acetohydroxyacid synthase (AHAS)-inhibiting herbicides. ACCase-inhibiting herbicides used in this study were aryloxyphenoxypropionate (APP) family members fluazifop-P and quizalofop-P along with cyclohexanedione (CHD) family members clethodim and sethoxydim. The level of resistance was very high for APP herbicides but low to nonexistent to CHD herbicides. With genetic resistance to APP herbicides, the resistance factors, the ratio of resistance to susceptible, were greater than 54 to 64 for homozygous individuals and greater than 9 to 20 for heterozygous individuals. Resistance to CHD herbicides was very low with resistance factors ranging from one to about five. Genetic segregation studies indicate a single gene is the cause of resistance to APP herbicides. Sequencing identified a single mutation that results in cysteine replacing tryptophan (Trp-2027-Cys). Trp-2027-Cys has previously been reported to provide resistance to APP but not CHD herbicides. The other wild sorghum evaluated in this study was resistant to AHAS-inhibiting herbicides including imidazolinone (IM) family member, imazapyr, and sulfonylurea (SU) family member, nicosulfuron. Resistance factors in this genotype were very high, greater than 770 for the IM herbicide and greater than 500 for the SU herbicide, for both herbicide chemical families. Genetic segregation studies demonstrate that resistance was controlled by one major locus and two modifier loci. DNA sequencing of the AHAS gene identified two mutations, Val-560-Ile and Trp-574-Leu. Val-560-Ile is of unknown importance, but valine and isoleucine are similar and residue 560 is not conserved. Trp-574 is a conserved residue and Leu-574 is a known mutation that provides strong cross resistance to IM and SU herbicides. The results of these studies suggest that these sources of APP, SU, and IM resistance may provide useful herbicide resistance traits for use in sorghum.
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Landry, Michael T. "The military might and activity of King Ahab." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0004/MQ46225.pdf.
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Beairsto, Shelagh Marie. "Dinjii Kat Chih Ahaa : Gwich'in notions of leadership." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0023/MQ51684.pdf.
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Laßmann, Paula, Jonathan Kießling, Stephan Mayer, Benedikt Janny, and Thomas Maier. "aHa – Der adaptive Handgriff der Zukunft." Thelem Universitätsverlag & Buchhandlung GmbH & Co. KG, 2019. https://tud.qucosa.de/id/qucosa%3A36944.
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Über die Gestalt eines optimalen Handgriffs hat sich Wilhelm Emil Fein als Erfinder der handgeführten Bohrmaschinen bereits vor hundert Jahren Gedanken gemacht (Schmid & Maier 2017). Der spanische Architekt Gaudì passte die Fenstergriffe im Casa Battlò in Barcelona Anfang des 20. Jahrhunderts der Handform an, die heute als antropomorphe Gegenform in der Forschung bekannt ist und im Griffdesign angestrebt wird (Schmid & Maier 2017). Die anthropomorphe Gegenform stellt das Pendant zu körpereigenen Formen dar und ermöglicht somit eine Maximierung der Kontaktfläche bei einer Minimierung der Flächenpressung. Die Vorteile hierbei sind eine gute Kraftübertragung bei geringer Druckstellenbildung. Bei einem nicht adaptiven Griff würde dessen Form verschiedene Hände in verschiedenen Nutzungsszenarien in ungewünschte Zwangshaltungen bringen, weswegen eine optimale Form nur durch einen adaptiven Griff sichergestellt werden kann. Aufgrund der unterschiedlichen Topographie von Händen ermöglicht ein individueller Griff die beste Kraftübertragung und einen idealen Komfort. Dementsprechend ist das Optimum ein kontinuierlich adaptiver Griff, den es bisher nicht auf dem Markt gibt (s. Stand der Forschung). Aufbauend auf einem beantragten Patent wird ein Demonstrator eines solchen Griffs entworfen. Dabei wird in der Einleitung auf die Problemstellung der Griffgrößen eingegangen, sowie der gewählte Anwendungsfall hergeleitet. Im Anschluss wird der Stand der Forschung erarbeitet. Darauffolgend wird auf die methodische Vorgehensweise sowie auf die konstruierten Prototypen eingegangen. Eine Diskussion und Ausblick runden den Beitrag ab. [... aus der Einleitung]
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Ataie, Abdul Ahad [Verfasser]. "QRPA-Rechnungen für Ladungsaustauschanregungen an exotischen Kernen / Abdul Ahad Ataie." München : Verlag Dr. Hut, 2011. http://d-nb.info/1013526570/34.
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Shelton, Lindsey Brooke. "Targeting the Hsp90/Aha1 Complex for the Treatment of Tauopathies." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7643.
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The microtubule associated protein, tau, is involved in regulating microtubule stability and axonal transport. When tau becomes hyperphosphorylated it can disassociate from the microtubules and start to aggregate. These tau aggregates are the hallmarks of many diseases known as tauopathies. The heat shock protein 90 kDa (Hsp90) chaperone network is highly involved in modulating client proteins, including tau. However, during aging and disease the Hsp90 chaperone network becomes highly imbalanced with some Hsp90/co-chaperone complexes increasing, while others are repressed. This imbalance in Hsp90/co-chaperone complexes could result in a worsening of tau pathology in Alzheimer’s disease.
Hsp90 inhibition has been of interest as a potential therapeutic for tauopathies for many years. However, issues with toxicity and bioavailability have dampened enthusiasm for Hsp90 as a viable therapeutic target. Hsp90 co-chaperones are currently being investigated for as potential therapeutic targets for tauopathies, with the hope that targeting co-chaperones will lead to more specific targeting without toxicity. One co-chaperone that has the potential to become a therapeutic target for tauopathies is the activator of Hsp90 ATPase homolog 1 (Aha1).
Aha1 is the only known stimulator of the ATPase of Hsp90, so targeting this particular co-chaperone could potentially mimic the effects of Hsp90 inhibition with more specificity. In this study we found that Aha1 enhanced Hsp90-mediated tau aggregation and increased insoluble tau accumulation in vitro. Additionally, a novel Aha1 inhibitor was able to reduce the formation of insoluble tau in vitro. We also investigated the effects of Aha1 overexpression in the rTg4510 mouse model, which is a tauopathy model that stably overexpresses the P301L mutation of tau. Overexpression of Aha1 in these mice increased the accumulation of insoluble and oligomeric tau. Furthermore, Aha1 overexpression led to cognitive deficits and neurotoxicity. Due to the effect of Aha1 overexpression on tau we wanted to investigate the effects of Aha1 knock-down in the rTg4510 mice. Incredibly, Aha1 knock-down led to reductions in pathological Gallyas silver positive tau tangles and was able to rescue neuronal loss. Overall, this work highlights Aha1 as an important regulator of tau pathology through Hsp90. The Hsp90/Aha1 complex could provide a novel therapeutic target for the treatment of tauopathies.
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Diaz, Infante Hernandez David Alberto. "Prediction and Prevention of Edge Fracture in Forming of AHSS." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563371149338966.
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Aha, Ulrich [Verfasser]. "Optimierung von Instandhaltungsstrategien bei unscharfen Eingangsdaten / Ulrich Aha." Kassel : Kassel University Press, 2013. http://d-nb.info/1056975121/34.
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Holmes, Joanna Louise. "Modulation of the Co-Chaperone AHA1 Affects HSP90 Function in Cancer Cells." Thesis, Institute of Cancer Research (University Of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504791.
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AHAl (Activator ofHSP90 ATPase) is a co-chaperone of the ATP-dependent molecular chaperone Heat shock protein 90 (HSP90) which is involved in the maturation, stabilization/degradation and function of oncogenic proteins. HSP90 operates in a multimeric complex driven by the binding and hydrolysis of ATP. Treatment of human cancer cells with the clinically evaluated HSP90 inhibitor 17-allylamino-l7- . demethoxygeldanamycin (l7-AAG) results in degradation of oncogenic client proteins via the ubiquitin-proteasome pathway. As AHAI increases the ATPase activity of HSP90, it was hypothesized that modulation of AHAI expression could influence the activity of client proteins and/or the cellular response to 17-AAG. Initial. studies were carried out to characterise the expression of AHAl in a panel of human cancer cell lines and the co-chaperone complexes in which it is found. Published data have suggested that AHAl was present only in the mature complexes with HSP90 once ATP had bound. Here, however, more detailed studies have shown that AHAI is found in both early and intermediate complexes and may have a role in driving the transition between the intermediate and mature complexes. The role of AHA 1 in the .cellular sensitivity to 17- AAG was determined by modulating AHAl expression. Overexpression of AHAl did not affect cellular sensitivity to 17-AAG, but did increase client protein activation without affecting their total levels. When AHAl levels were selectively knocked down (>80%) using an RNAi approach, client protein activation was decreased. The AHAl knockdown also resulted in a significant increase in sensitivity to 17-AAG, due in part to an increase in apoptosis. Inducible and constitutively stable RNAi models were also developed to further confirm these findings ill vitro and ill vivo. Overall, the results demonstrate that reduction of AHAl levels decreased activation of key signal transduction proteins and sensitized cancer cells to 17-AAG. Gene expression microarray analysis of AHAl knockdown revealed that the mechanism by which AHAI depletion sensitized cells to l7-AAG involved NAD(P)H dehydrogenase quinone 1 (NQOl), the expression of which was significantly increased with AHAl knockdown. Thus modulation of AHAI could be a therapeutic strategy to increase sensitivity to HSP90 inhibitors. The cDNA microarray analysis was also used to identify potential pharmacodynamic markers for future AHAl inhibitors.
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Wills, Theodore W. "Cognitive operations and the "aha" effect : revision not confusion /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2002.
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Thesis (Ph.D.)--Tufts University, 2002.Advisr: Salvatore Soraci, Jr. Submitted to the Dept. of Psychology. Includes bibliographical references (leaves 71-73). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Kim, Hyunok. "Prediction and elimination of galling in forming galvanized advanced high strength steels (AHSS)." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1204515296.
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Godha, Anshul. "Microstructural effects on fatigue damage evolution in advanced high strength sheet (AHSS) steels." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53510.
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An understanding of the damage evolution prior to crack initiation in advanced structural materials is of vital importance to the fatigue community in both academia and industry. Features known as the Persistent Slip Bands (PSBs) play an integral role in this damage evolution. Therefore, PSBs have been the focus of a lot of science-based investigations over the years. However, most existing studies in this area are restricted to analysis of PSBs in single crystal face centered cubic (FCC) materials. Moreover, these studies lack a quantitative analysis of the evolution of the fatigue damage (or PSBs) as a function of the material microstructure. This is especially true for relatively modern materials such as the Advanced High Strength Structural (AHSS) steels that are gaining a lot of importance in the automotive sector. Accordingly, the objective of this research is to quantitatively characterize evolution of PSBs in three AHSS steels having different microstructures as a function of number of fatigue cycles and strain amplitude. For this purpose strain controlled interrupted fatigue tests have been performed on two dual phase steels (DP-590 and DP-980) having different relative amounts of tempered martensite and a ferritic high strength low alloy steel (HR-590). Digital image analysis and Stereology have been used for unbiased quantitative characterization of the evolution of global geometry of the PSB colonies as function of number of fatigue cycles and strain amplitude. Evolution of PSB colonies has been couched in terms of variation of PSB colony volume fraction and total surface area unit volume, and total surface area of individual PSBs per unit volume and three-dimensional angular orientation distribution of the PSBs. For this purpose, new stereological techniques have been developed for estimation of the three-dimensional angular orientation distribution. The stereological data reveal that during strain controlled in these AHSS steels, volume fraction of the PSB colonies varies linearly with the their total surface area per unit volume. Detailed analysis of the stereological data leads to a simple geometric model for evolution of the PSB colonies in the three AHSS steels, which accounts for all observed data trends.
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Tschuschke, Volker. "Die Edelherren von Ahaus ein Beitrag zur Geschichte des westfälischen Adels im Mittelalter /." Vreden : Landeskundliches Institut Westmünsterland, 2007. http://books.google.com/books?id=3GjaAAAAMAAJ.
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Madgwick, Sebastian O. H. "AHRS algorithms and calibration solutions to facilitate new applications using low-cost MEMS." Thesis, University of Bristol, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.681552.
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Microelectromechanical System (MEMS) technology is advancing rapidly. Gyroscopes, accelerometers and magnetometers, also referred to as an Inertial Measurement Unit (IMU), has traditionally been associated with aerospace and industrial robotics but is now within every smart phone. The proliferation of these low-cost devices has facilitated countless new applications with many more still unrealised. This dissertation presents work towards this end. A significant contribution of this work was the development of novel Attitude and Heading Reference System (AHRS) algorithms that fuse together sensor data from an IMU to provide an absolute measurement of orientation relative to the Earth. The novel work presented on non-gyro IMU s demonstrated the potential practical benefits of such kinematically redundant sensor arrays. Low-cost MEMS can only be fully utilised if they are combined with a calibration solution to provide precise measurements with a determined accuracy. This dissertation presents a comprehensive calibration solution to the specific requirements of these sensors based on extensive characterisations investigations. The calibration solutions enable sensors costing <10 United States Dollar (USD) to achieve a static pitch/roll accuracy of <10 and a static heading accuracy of <2°. This performance is equivalent to commercial 1M Us costing up to 3000 USD. The AHRS algorithm and sensor calibration works were brought together in the development of three IMU hardware platforms. To date, >500 have been sold and the open-source associated algorithm downloaded> 10,000 times. Each platform addressed a specific design need and together these facilitated a wide range of new applications; demonstrated by the numerous scientific publications that resulted from collaborative projects and user projects.
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Gomes, Francisco Edvan Rodrigues. "Clonagem, expressão e estudo de 3 co-chaperonas de Leishmania braziliensis." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-16092011-160310/.
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A leishmaniose é uma enfermidade infecciosa causada por várias espécies de parasitas do gênero Leishmania e representa um dos principais problemas de saúde pública nos países subdesenvolvidos. No hospedeiro, a sobrevivência do protozoário causador dessa doença depende de uma classe especial de proteínas, as chaperonas moleculares ou proteínas de choque térmico como também são conhecidas. A função dessas proteínas é auxiliar no processo de enovelamento protéico, no transporte de proteínas entre as membranas e em muitas outras importantes funções celulares. Neste processo, as chaperonas moleculares são auxiliadas pelas suas co-chaperonas que desempenham função de destaque. Dentre as principais famílias de chaperonas moleculares temos as Hsp70 e as Hsp90 com suas respectivas co-chaperonas, as Hsp40 e a Aha1. O presente trabalho pretendeu inicialmente expressar e purificar as co-chaperonas moleculares Hsp40I e Hsp40II de L. braziliensis para realizar estudos de caracterização estrutural por meio das técnicas de dicroísmo circular e fluorescência. Contudo, a insolubilidade dessas proteínas, que pode ter sido causada pela presença de mutações nas sequências de DNA, motivou a caracterização de outra co-chaperona, a Aha1 de L. braziliensis (LbAha1). A LbAha1 foi expressa no sobrenadante celular e purificada por três etapas cromatográficas (troca aniônica, afinidade por íons cálcio e gel filtração). A análise da sequência de aminoácidos dessa proteína mostra que ela possui 9 resíduos de triptofano distribuídos nos dois domínios característicos da LbAha1. Estudos de desnaturação química por uréia, monitorados pelas técnicas de dicroísmo circular e fluorescência, mostram que os dois domínios da LbAha1 apresentam estabilidades diferentes. Os estudos estruturais realizados permitiram identificar as transições com o respectivo domínio.Leishmaniasis is an infectious disease caused by several species of Leishmania species and represents major public health problems in developing countries. In the harborer, the survival of the parasite that cause this disease depends on a special class of proteins, molecular chaperones or heat shock proteins as they are also known. The function of these proteins is to assist in protein folding, transport of proteins and many other important cellular functions. In this process the molecular chaperones are helped by their co-chaperones that play a prominent role. Among the main families of molecular chaperones, there are Hsp70 and Hsp90 with their respective co-chaperones, Hsp40 and the Aha1. The present work, initially pretended to express and purify the molecular co-chaperones Hsp40I and Hsp40II of the L. braziliensis for structural characterization by spectroscopic techniques like fluorescence and circular dichroism. However, the insolubility of these proteins, possibly caused by the presence of mutations in their DNA sequences, led to the characterization of another co-chaperone, the Aha1 of the L. braziliensis. These proteins were expressed in the cell supernatant and purified by three chromatographic steps (anion exchange, affinity for calcium ions and gel filtration). The analysis of the DNA sequence of this protein shows that it has nine Trp residues distributed between the two domains and by urea denaturation studies monitored by fluorescence techniques and circular dichroism show that they have different stabilities.
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Seraphim, Thiago Vargas. "Estudo estrutural da co-chaperona Aha1 (Activator of Hsp90 ATPase 1) de Leishmania braziliensis e da sua ação sobre o ciclo funcional da Hsp90." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/75/75133/tde-25112015-102054/.
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As chaperonas moleculares atuam no enovelamento de proteínas, montagem de complexos, prevenção/recuperação de proteínas de agregados e encaminhamento de proteínas mal enoveladas para depuração. As Hsp90 são chaperonas moleculares que atuam estabilizando proteínas relacionadas a vias de sinalização, crescimento celular, processos transcricionais e traducionais, estabilidade do genoma, entre outras, sendo essencial para a viabilidade celular. Em protozoários do gênero Leishmania, as Hsp90 são imprescindíveis no desenvolvimento, adaptação e transformação celular. Estes fatores fazem das Hsp90 alvos potenciais para o tratamento de patologias, como a leishmaniose, uma doença tropical negligenciada. As Hsp90 são homodímeros flexíveis onde cada protômero é dividido em três domínios denominados N, M e C. As Hsp90 possuem um ciclo conformacional associado ao seu ciclo funcional e sua baixa atividade ATPásica, o qual é direcionado e regulado por proteínas auxiliares, as co-chaperonas. A co-chaperona Aha1 atua estimulando a atividade ATPásica da Hsp90, participando da maturação de proteínas quinase e receptores de hormônios. O objetivo deste trabalho foi caracterizar estruturalmente a proteína Aha1 de L. braziliensis (LbAha1) e seu mecanismo de interação com a Hsp90 desse organismo (LbHsp90). A LbAha1 é formada por dois domínios, LbAha1N e LbAha1C, conectados entre si por um linker flexível. Experimentos de identificação in vivo mostraram que a LbAha1 e LbHsp90 são proteínas cognatas. A LbAha1 e as construções de seus domínios (LbAha1N e LbAha1C) recombinantes foram obtidas puras e enoveladas. A LbAha1 é estruturada em dois domínios com diferentes estabilidades, que não interagem entre si e se enovelam independentemente, porém influenciam-se reciprocamente. Em solução, a LbAha1 se comporta como um monômero alongado e possui notável flexibilidade, com dimensão suficiente para interagir com os domínios N e M da LbHsp90. A análise da interação entre a LbAha1 e LbHsp90 revelou que a associação destas proteínas é dirigida entalpicamente, ocorrendo através de interações eletrostáticas e com estequiometria de 2 moléculas de LbAha1 por dímero de LbHsp90. O mapeamento de regiões envolvidas na interação indicou que o domínio LbAha1N e o domínio M da LbHsp90 compõem o cerne da interação e somente a LbAha1 íntegra é capaz de encaminhar a LbHsp90 para um estado fechado. Experimentos de cinética enzimática mostraram que somente a LbAha1 íntegra estimula a atividade ATPásica da LbHsp90 por meio de um mecanismo cooperativo positivo. Assim, é proposto que a conexão entre os domínios da LbAha1, via linker, é essencial para o direcionamento da LbHsp90 para um estado conformacional fechado e competente na hidrólise de ATP.Molecular chaperones play a role in protein folding, complex assembly, prevention/recover of proteins from aggregates and targeting misfolded proteins to depuration. Hsp90 molecular chaperones work stabilizing proteins related to signaling pathways, cell growth, transcription and translation processes, genome stability, among others, and are essential to cell viability. In protozoa of the genus Leishmania, Hsp90s are indispensable for cell developing, adaptation and transformation. These factors make Hsp90s potential targets for pathologies treatment, such as leishmaniasis, a neglected tropical disease. Hsp90s are flexible homodimers and each protomer is divided into three domains named N, M and C. Hsp90s have a conformational cycle associated to its functional cycle and low ATPase activity, which is directed and regulated by auxiliary proteins, so-called cochaperones. Aha1 co-chaperone stimulates Hsp90 ATPase activity, participating on protein kinase and hormone receptors maturation. This work aimed to characterize the structure of the Aha1 from L. braziliensis (LbAha1) and its mechanism of interaction with the Hsp90 from the same organism (LbHsp90). LbAha1 is formed by two domains, LbAha1N and LbAha1C, connected to each other by a flexible linker. In vivo experiments identified LbAha1 and LbHsp90 as cognate proteins. Recombinant LbAha1 and its domains construct (LbAha1N and LbAha1C) were obtained pure and folded. LbAha1 is divided into two domains with dissimilar stabilities and they do not interact to each other. In spite of this they fold independently and influence each other reciprocally. LbAha1 behaves as an elongated monomer in solution and has a remarkable flexibility, with sufficient dimension to interact to LbHsp90 N and M domains. The analysis of the LbAha1-LbHsp90 interaction revealed that the association between these two proteins is enthalpically driven, occurring through electrostatic interactions in a stoichiometry of 2 LbAha1 molecules per LbHsp90 dimer. Domain mapping experiments indicated that LbAha1N and LbHsp90 M domains compose the core of the interaction and only full length LbAha1 is able to direct LbHsp90 toward a closed state. Enzyme kinetics experiments showed that only full length LbAha1 stimulates LbHsp90 ATPase activity through a positive cooperative mechanism. Thus, it is proposed that the connection between the LbAha1 domains, via linker, is essential to direct the LbHsp90 toward a closed and ATPase-competent conformational state.
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Merecz, Robert Jerzy. "Jezebel's Kingdom : the Queen as a primary character in 1 Kgs 16:29 – 2 Kgs 10." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/5468.
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The main thesis of this dissertation is that Jezebel is a primary character in 1 Kgs 16 – 2 Kgs 10. This may be observed both in the so-called Elijah and Elisha cycles. One of the main purposes, if not the purpose, of the stories contained within the Elijah cycle is to enhance the polemic against Jezebel and against the Baal cult which had been introduced by her, and not merely to convey events from Elijah‘s ministry. The choice of the characters and details revealed about their background indicate that the Elijah cycle is only partially concerned with the prophet, while it is directed importantly also against the queen and Baal. Elisha‘s ministry follows that of Elijah. His cycle prepares the reader for the punishment of Jezebel by revealing different details of the final moments of the queen‘s life and the events surrounding her death. Even though the reader will find only two direct references to the queen in 2 Kgs 2-8, the text sheds some light on the queen, her character and her death. The narrative also introduces new characters whose role is to be a foil or a contrast to the queen. The thesis, then, argues that Jezebel is a primary character in the narrative of the middle part of the Books of Kings. It must be said, however, that many elements of the argument against Jezebel operate on the narrator‘s, and not on characters‘, level. Besides a few direct references to Jezebel and to her activities, she herself quite often remains absent from the stage. It is only when one raises one‘s sights from the characters‘ to the narrator‘s perspective that he or she may notice abundance of allusions, prefigurations, comparisons, use of foils, and other devices that enhance the argument against the queen and make her a primary character in 1 Kgs 16:29 – 2 Kgs 10.
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Emídio, Marco. "Reconhecimento de entidades em documentos do "AHS - Arquivo Histórico Social"." Master's thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/15193.
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A presente dissertação visa efectuar a extracção de informação de documentos históricos,
provenientes do Arquivo Histórico-Social (AHS), e construir um suporte digital para os
mesmos ao abrigo do projecto de investigação cientifica da Fundação para a Ciência e a
Tecnologia (FCT).
Para a extracção de informação dos documentos, aplicou-se a ferramenta Minorthird,
que possibilita a extracção de entidades mencionadas dentro dos textos, para posterior
avaliação de resultados, possibilitando a pesquisa de elementos chave nos textos introduzidos
no arquivo digital.
Os resultados obtidos revelaram-se promissores, tendo-se obtido uma precisão média
de 0,8753 e uma cobertura media de 0,5075 na identificação de pessoas, entidades, locais
e datas. Os melhores resultados foram obtidos na identificação de entidades, seguida das
datas, lugares e pessoas.
O algoritmo Conditional Random Fields (CRF) demonstrou um melhor comportamento
para a identificação de entidades, datas e locais, tendo o algoritmo Support Vector
Machines (SVM) apresentado melhores resultados para a identificação de pessoas.
Na concepção do arquivo digital, utilizaram-se ferramentas como Archon, Joomla!,
estando o portal disponível em http://arquivo-digital.xdi.uevora.pt/projecto/; ABSTRACT: This dissertation aims to perform information extraction of historical documents from
AHS, and build a digital archive for it promoted by the FCT scienti c research project.
For the document information extraction, a tool called Minorthird was used, which
enables extraction of named entities inside texts, for later results evaluation, enabling
the search of key elements in the inserted texts in the digital archive.
The results proved to be promising, getting a mean precision of 0,8753 and a mean
recall of 0,5075 by identifying persons, entities, places and dates. The best results were
obtained by identifying entities, followed by dates, places and persons.
The CRF algorithm presented better performance in identifying entities, dates and
places, having the SVM algorithm showed best results recognising persons.
The Archon and Joomla! tools were responsible of creating the digital archive, being
the website available at http://arquivo-digital.xdi.uevora.pt/projecto/.
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Hilloowala, Franak. "An analysis of Ibn Abi Usaybi`ah's `Uyun al-anba' fi tabaqat al-atibba'." Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/289096.
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This dissertation is a partial translation of the thirteenth-century Islamic physician, Ibn Abi Usaybi'ah's biographical dictionary, the 'Uyun al-anba' fi tabaqat al-atibba' ( Sources of Information on Classes of Physicians) and an historical analysis of the 'Uyun. The 'Uyun is a biographical dictionary which encompasses the biographies of physicians from the ancient Greek period through the author's time, the thirteenth century. It contains the lives and works of the most elite physicians of these periods. The translation portion of the dissertation is of the fourteenth chapter of the 'Uyun which is the chapter on physicians of Egypt from the 'Abbasid period to the early Mamluk period. The historical analysis of this dissertation is an examination of the contents of the 'Uyun to see what it reveals about the status of physicians during this period and about the author's intentions in writing this book. Since the author was from Syria and studied in both Syria and Egypt, I have based my analysis mainly on the translation of the chapter on Egypt and also on evidence found in the fifteenth chapter on Syria. Thus, this dissertation serves to give modern scholars incite into the mentality of the author and his class during this time period in the Islamic world.
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Valoti, Elisabetta. "Genetic factors associated with anti-factor H autoantibodies in atypical hemolytic uremic syndrome (aHUS)." Thesis, Open University, 2018. http://oro.open.ac.uk/55853/.
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Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy characterized by renal failure and determined by genetic and acquired defects of alternative pathway (AP) of the complement system. Autoantibodies against factor H (anti-FHs), a regulator of the AP, were reported in 10% of patients, and are associated with the deficiency of factor H related 1 (FHR1), a FH homologous protein. The aim of this thesis was to evaluate the contribution of genetics to the development of anti-FHs in aHUS. Thirty patients affected by aHUS resulted positive for anti-FHs (9.8%) and FHR1 deficiency was present in 83.3% of them. A healthy control also showed anti-FHs in concomitance with FHR1 deficiency documenting that the lack of FHR1 strongly predisposed to anti-FH development also in healthy subjects although this condition was not sufficient for the disease manifestation. The presence of infectious prodromal signs and an age at the disease onset around 8 years indicated that common infections may trigger the development of autoantibodies in subjects with at risk genetic background. Likely pathogenetic variants in complement genes were observed in 37% of our patients with anti-FHs. At variance, common variants in complement genes did not seem to contribute to the disease, as documented by comparing patients with super controls, unaffected subjects carrying FHR1 deficiency. Finally, I report that the HLA-DRB1*11:04 allele could be a predisposing genetic variant for anti-FH associated aHUS. Further works will be necessary to confirm this finding and to explore the presence of other genetic susceptibility factors that, in combination with the HLA-DRB1*11:04 allele and the FHR1 deficiency, could increase the risk for anti-FHs.
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Bäckström, Nathalie. "Wasteland : A scattered recycle station as a neighbourhood meeting spot in Ahos park, Kiruna." Thesis, Umeå universitet, Arkitekthögskolan vid Umeå universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-173271.
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Maga, Tara Kristen. "Unraveling the complex genetics of atypical hemolytic uremic syndrome." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/2935.
Full textAbstract:
Atypical hemolytic uremic syndrome (aHUS) is characterized by acute renal failure, thrombocytopenia, and microangiopathic hemolytic anemia. aHUS is far less common and more severe than typical HUS, which is caused by E. coli infection and manifests as diarrheal illness. The pathogenesis of the disease is linked to dysregulation of the alternative pathway of the complement cascade. Mutations in the complement regulators factor H (CFH), membrane cofactor protein (MCP), factor B (CFB), and factor I (CFI) have been implicated in aHUS. These loss or gain of function mutations lead to uncontrolled complement activity and immune-mediated host cell damage. Establishing a genetic etiology is important as it helps to direct treatment during the acute phase of disease and when transplantation is considered. It has been shown in previous studies that the age of onset as well the severity of the disease is correlated with the type of mutation a patient is found to carry. In forty percent of aHUS patients a mutation in CFH, MCP, CFB, CFI, C3 or THBD is not detected. These data strongly suggest that other genetic factors are involved in the pathogenesis of aHUS and that comprehensive mutation detection in aHUS patients is essential to provide diagnostic and prognostic information, and improve their clinical care.
My thesis work has aimed to identify the other genetic contributors to this disease. To achieve this goal we began by screening the largest American cohort of aHUS patients for mutations in CFH, MCP, CFB, CFI, C3, THBD as well as CFHR5. This study identified over thirty novel mutations and suggests a more comprehensive genetic screening method that would better serve patients. To complement these studies multiplex ligation-dependent probe amplification was used to detect genetic rearrangements within the factor H related genes. A number of unique fusion proteins were seen in aHUS patients, all of which are predicted to affect the function of CFH. To discover mutations in novel genes that are causally related to aHUS, we have optimized a platform called CASCADE (Capture and Sequencing of Complement-Associated Disease Exons), which is based on targeted-genome capture and next-generation sequencing. This study revealed an unexpected role for ADAMTS13 and other genes in the coagulation pathway as modifiers of aHUS. Using functional assays we show two of the ADAMTS13 variants alter the behavior of this protein. This work has changed how we view this disease by identifying several novel candidate genes, for which we hope future analysis will lead to a better understanding of their role in aHUS. Using this knowledge we can provide better and more personalized treatments for patients.
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Palmqvist, maja. "Kan haha - leda till - aha? : Kan skrattyoga påverka kreativiteten och sinnestämningen?" Thesis, Mittuniversitetet, Institutionen för samhällsvetenskap, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-11741.
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Abstrakt: det finns mycken forskning som visar att humor/skratt i olika former kan bidra till positivare sinnestämning och ökad kreativitet i arbetslivet. En relativt ny metod är skrattyoga - en företeelse som knappt varit föremål för studier i Sverige. Syftet med denna undersökning var att studera om skrattyoga påverkar sinnesstämningen och kreativitet, om kvinnor och män påverkas olika. Ett kvasiexperiment med skrattyoga genomfördes vid ett tillfälle på en vårdcentral som var försöksgrupp och en annan vårdcentral som var kontrollgrupp utan skrattyoga. Totalt trettio respondenter testades med kreativitets- och sinnesstämningsfrågeformulär. Inga signifikanta skillnader påvisades varken mellan skrattyoga och sinnesstämning, kreativitet eller genus. Dock påvisades korrelation mellan sinnesstämning och kreativitet.
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Longhurst, Leigh Anne. "The transformational potential of 'aha' moments in life coaching and beyond." Thesis, Oxford Brookes University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.579546.
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"Aha" moments of insight are considered fundamental to personal transformational but the phenomenology of insight and intuition are poorly understood phenomena (Levitt et ai, 2004). Life coaching has little to say on the subject since the body of literature relating to coaching is still in its foetal stages (Griffiths, 2005). This research addresses both of these problems by exploring whether "Aha" moments are fundamental to the transformational change sought by the "Co-Active" model of life coaching (Whitworth et ai, 1998, 2007). A grounded theory methodology was employed to investigate the phenomenology of insight. Participants were selected for their use of the Co-Active coaching model and their willingness to render phenomenological accounts of "Aha" moments. Co-Active coaches and their clients recorded their experiences of insight during coaching sessions. Methods involved diary-keeping, questionnaires and interviews. Diaries captured the lived experience of the "Aha" moment while questionnaires and interviews revealed its lingering effects on beliefs and behaviours. Each phase of data collection informed the next. By comparing the findings of this research with other fields of inquiry into insight, an integral methodological element was added to the grounded approach. Findings reveal the "Aha" moment to induce 'alethia' the Greek term meaning to step out of lethargy and into truth. The moment can be experienced not only cognitively but somatically and emotionally, striking many chords across a spectrum of consciousness from body, to mind, to soul to spirit. The more chords the "Aha" moment strikes, the greater the resonance and potential for cognitive and behavioural change. Findings suggest that insight comes from intuition and can arise in cognition as a purely mental event or can be experienced in transpersonal ways, where such intuition is described as 'spiritual'. The study suggests that the ontology of a truly holistic coaching model would offer the possibility of transformational change at the levels of ego, mind, body, soul and spirit. Key words: Aha moment, insight, intuition, Co-Active coaching, spectrum of consciousness, transformational change. 2
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Kudrowitz, Barry M. (Barry Matthew). "Haha and aha! : creativity, idea generation, improvisational humor, and product design." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/61610.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 107-116).
It is widely recognized that innovation and creativity is the new competitive battleground for product development firms. Engineers and product designers are now expected to be highly creative, prolific idea generators in addition to being analytically competent. Thus, it is of interest to study methods to improve a designer's idea generation capabilities. It is believed that wit, being spontaneous humor production, is strongly related to creativity as both involve making nonobvious connections between seemingly unrelated things. This thesis looks into the realm of humor and improvisational comedy to suggest means of enhancing creative output in blue-sky product design idea generation. We have found that the ability to quickly generate many ideas is strongly correlated (r2=.82) with being able to come up with a single, promising, creative idea. It was also found that, with appropriate training, individuals may learn to become more prolific idea generators. Furthermore, improvisational comedians were more proficient at new product idea generation than professional product designers, and methods for training comedians can be effectively adapted to product design idea generation. In a study where 84 participants (students, professional designers and improvisational comedians) took a cartoon caption humor test and a nominal product brainstorming test, we found that improvisational comedians on average produced 20% more product ideas and 25% more creative product ideas than professional product designers. Furthermore, the few individuals that were highly prolific in both creative product ideation and humorous cartoon caption production had an improvisational comedy background. Many of the games used in improvisational comedy training are intended to promote associative thinking. We designed an improvisational comedy workshop composed of these association-based games. A group of 11 subjects who participated in this workshop increased their idea output on average by 37% in a subsequent product brainstorming session. Our findings suggest that improvisational comedy games are a useful warm-up for idea generation, that prolific generation is not a domain-specific ability and that it is possible to teach creativity. Ultimately, this work can lead to the development of tools and methods that designers can use to improve their idea generation skills.
by Barry Matthew Kudrowitz.
Ph.D.
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Santerre, Gabrielle. "Variabilité spatio-temporelle des THM et AHA iodés dans l'eau potable." Master's thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/32884.
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L’utilisation d’oxydants, comme l’hypochlorite de sodium, est une stratégie très efficace en traitement de l’eau pour inactiver les microorganismes responsables de plusieurs maladies. Toutefois leur utilisation favorise également la formation de sous-produits de la désinfection (SPD), tels que les trihalométhanes et les acides haloacétiques. La présence d’iodure et de bromure dans l’eau brute peut également conduire à la formation d’autres familles de SPD, les trihalométhanes iodés (THMi) et les acides haloacétiques iodés (AHAi). Cette étude a comme objectif d’évaluer la variabilité des THMi et AHAi dans deux petits réseaux de distribution de la région de Québec (notés R1 et R2) ainsi que de mesurer l’enlèvement des THMi lors de l’utilisation de filtres domestiques. L’échantillonnage de l’eau s’est effectué entre juin et décembre 2017 sur différents points dans l’usine de traitement des eaux et dans le réseau de distribution. Pour le réseau R1, des concentrations moyennes de 2,99 μg/L en THM iodés et de 0,74 μg/L en AHA iodés sont observées, alors que la concentration maximale obtenue est de 4,02 μg/L pour les THM iodés et de 2,46 μg/L pour les AHA iodés. Des concentrations moyennes de 2,98 μg/L en THM iodés et de 0,51 μg/L en AHA iodés sont observées dans le Réseau R2, alors que la concentration maximale obtenue est de 4,05 μg/L pour les THM iodés et de 2,33 μg/L pour les AHA iodés. Les concentrations en THM iodés et en AHA iodés augmentent dans l’usine, particulièrement à la suite de la post chloration et du passage de l’eau par le bassin de contact. Les concentrations en THM iodés restent ensuite stables dans le réseau de distribution alors que celles des AHA iodés diminuent. De plus, l’enlèvement des THMi s’avère très efficace après la filtration de l’eau sur un filtre domestique de type BritaMD, avec un pourcentage d’enlèvement moyen de 100%.The use of oxidants, such as sodium hypochlorite, is a very effective strategy in treating water to inactivate microorganisms responsible for several diseases. However, their use also favors the formation of disinfection by-products (SPD), such as trihalomethanes and haloacetic acids. The presence of iodide and bromide also allows the formation of other families of SPD, iodinated trihalomethanes (THMi) and iodinated haloacetic acids (AHAi). The purpose of this study is to evaluate the variability of THMi and AHAi in two small distribution networks in the Quebec City region (R1 and R2) and to measure the removal of THMi when using household filters. Water sampling took place between June and December 2017 at various points in the water treatment plant and in the distribution network. For the R1 network, mean concentrations of 2.99 μg / L in iodinated THM and 0.74 μg / L in iodinated AHA were observed, while the maximum concentration achieved was 4.02 μg / L for THMs. iodized and 2.46 μg / L for iodinated AHAs. Mean concentrations of 2.98 μg / L in iodinated THM and 0.51 μg / L in iodinated AHA were observed in Network R2, while the maximum concentration obtained was 4.05 μg / L for iodinated THMs. and 2.33 μg / L for iodinated AHAs. Iodine THM and iodinated AHA concentrations increase in the plant, particularly because of post-chlorination and passage of water through the contact basin. The iodinated THM concentrations then remain stable in the distribution network while those of the iodinated AHAs decrease. On the other hand, the removal of THMi is very effective after filtration of water on a BritaMD type household filter, with an average removal percentage of 100%.
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Bellamri, Medjda. "Activation métabolique et génotoxicité des Amines Hétérocycliques Aromatiques (AHA) chez l’Homme." Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1B033/document.
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Les amines hétérocycliques aromatiques (AHA) sont des contaminants de l'environnement et de l'alimentation, majoritairement formés lors de la cuisson de viande et poisson ainsi que dans la fumée de cigarette et les gaz d'échappements. Les AHA sont mutagènes chez la bactérie, cancérogènes multi-sites chez le rongeur et sont classées comme cancérogènes possibles ou probables chez l'Homme par l'IARC. Il est aujourd'hui indispensable de caractériser des biomarqueurs d'exposition dérivés des AHA (adduits à l'ADN et métabolites) pour améliorer l'estimation du risque chez l'Homme. Des résultats de l'équipe ont démontré que le 2-amino-9H-pyrido[2,3-b]indole (AαC) forme des niveaux d'adduits à l'ADN élevés dans les hépatocytes humains. Ces niveaux sont plus élevés que ceux formés par les autres AHA. L'objectif de cette thèse est de mieux comprendre le potentiel génotoxique d'AαC chez l'Homme. Nos travaux ont démontré que les adduits à l'ADN dérivés d'AαC sont persistants dans les hépatocytes humains et formés à des doses aussi faibles que 1nM. De plus, le CYP1A2 a été confirmé comme enzyme majoritaire dans la bioactivation d'AαC dans le foie humain. Nous avons également caractérisé les métabolites majeurs dérivés d'AαC dans les hépatocytes humains. Cette étude a permis d'établir pour la première fois une corrélation entre l'activité catalytique du CYP1A2, la formation d'AαC-HN2-O-Gl et la formation des adduits à l'ADN dérivés d'AαC. Le métabolite AαC-HN2-O-Gl étant réactif vis-à-vis de l'ADN in vitro, nos travaux confortent l'hypothèse que la voie des UDP-Glucuronosyltransférases (UGTs) est une nouvelle voie de bioactivation d'AαC dans le foie humain. De plus, nous avons montré que les adduits à l'ADN dérivés des AHA sont formés dans les lymphocytes T humains activés et en particulier les adduits en position C8 de la guanine dérivés d'AαC. Au total, ces travaux ont permis l'identification de métabolites stables et des adduits à l'ADN, potentiels biomarqueurs d'exposition à AαC, qui sont indispensables pour une meilleure estimation du risque génotoxique d'AαC chez l'HommeHeterocyclic aromatic amines (HAA) are environmental and food contaminants, mainly formed during meat and fish cooking, but also in cigarette smoke and exhaust gaz. HAA are mutagenic in bacteria, carcinogenic in rodents and are classified as possible or probable human carcinogens by IARC. Today it is essential to characterize exposure biomarkers i.e. DNA adducts and metabolites, to assess the human risk associated with HAA. The research team has previously demonstrated that 2-amino-9H-pyrido[2,3-b]indole (AαC) form high levels of DNA adducts in human hepatocytes. These levels are greater that those derived from other HAAs. Thus, the aim of this thesis was to better understand the genotoxic potential of AαC in human. We demonstrated that in human hepatocytes, DNA adducts derived from AαC are persistent and formed at doses as low as 1nM. Moreover, we confirmed that CYP1A2 is the major enzyme implicated in the bioactivation of AαC in human liver. We have also characterized the major metabolites derived from AαC formed in human hepatocytes. This study allows, for the first time, the establishment of a correlation between the catalytic activity of CYP1A2, AαC-HN2-O-Gl formation and AαC derived DNA adducts formation. AαC-HN2-O-Gl being reactive toward DNA in vitro, our work reinforces the hypothesis that the UDP-glucuronosyltransferase (UGTs) pathway is a new bioactivation pathway for AαC in human liver. Moreover, we demonstrated the formation of HAA derived DNA adducts, especially those derived from AαC at position C8 of guanine, in activated human T lymphocytes. Taken together, our data lead to the identification of stable metabolites as well as DNA adducts which are potentials AαC exposure biomarkers in human. These biomarkers are essential for a better assessment of the genotoxic risk of AαC in human
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McAllister, Carlota Pierce 1969. "This pageant which is not won: The Rabin Ahau, Maya women, and the Guatemalan nation." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/278431.
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The "Rabin Ahau," Daughter of the King in Q'eqchi, is elected annually in a pageant in Coban, Guatemala to represent indigenous women before the Guatemalan nation. Although the contest takes the form of a beauty pageant, the criterion on which the candidates are judged is their authenticity as Maya women; their authenticity, in turn, guarentees Guatemala's distinctiveness in the international community of nations. This thesis explores what signifying authenticity requires of would-be Rabin Ahaus, when being Maya at all in Guatemala has historically been life-threatening. It links the aestheticization of Indianness to the ethnocidal racism which literally erases Maya bodies from the national territory, and examines how Guatemalan nationalist discourse uses mimesis and commodification of "the Indian" to create and control an Indian essence; it indicates, also, how the participants in the contest work mimetic excess to triangulate official authenticity and assert different meanings of the Maya.
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Wang, Kai Ph D. Massachusetts Institute of Technology. "Edge fracture of AHSS sheets under out-of-plane loading followed by in-plane loading." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100151.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 193-198).
In recent years edge fracture has become a challenge in the manufacturing industry with the dramatical increase in the application of light-weight materials such as Advanced High Strength Steels (AHSS) and aluminum alloys. A premature edge cracking is observed in components with blanked/trimmed/pierced edges during the subsequent metal forming process. To understand the underlying physical mechanism and to establish a reliable CAE model, the thesis carries out a comprehensive experimental and numerical investigation on edge fracture of a commercially available DP780 steel sheet. The study reveals that it is the substantial plastic deformation introduced during the out-of-plane sheet blanking process that compromises the material ductility within the Shear Affected Zone (SAZ), and subsequently causes the edge to fracture prematurely under the in-plane edge stretching. To simulate the fracture behavior under such a complex a loading path, the fracture initiation is modeled using the concept of a scalar damage indicator that consists of two parts which are accumulated at different stages. The first one is accumulated during the sheet blanking process, referred to as pre-damage, while the second part is produced by the following metal forming. In such a modeling frame work, a corner stone is to determine the first part of pre-damage within the SAZ. This is achieved by a hybrid experimental and numerical method. Aided by microscopic examinations on cracked surfaces, the study shows that the pre-damage distribution within the SAZ follows an exponential function that drops from the critical value of unity at the edge surface to zero over the width of the SAZ. The obtained pre-damage is then introduced as the initial damage value during the following metal forming process. Based on a detail experimental characterization, a plasticity and fracture model is introduced to describe the material behavior under investigation. The model is based on the von Mises yield condition, a non-associated Hill'48 flow potential and an isotropic hardening law, together with the MMC fracture locus description with dependence on both stress triaxiality and Lode angle parameter. The proposed model successfully predict edge fracture in numerical simulation.
by Kai Wang.
Ph. D.
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Alodail, Abdullah Kholifh. "Students’ Attitudes Toward the Use of Hearing Aids in Al-Ahsa, Kingdom of Saudi Arabia." Ohio University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1306953223.
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Alshawa, Majd. "Contribution à la cartographie mobile : développement et caractérisation d’un système basé sur un scanner laser terrestre." Strasbourg, 2009. https://publication-theses.unistra.fr/public/theses_doctorat/2010/ALSHAWA_Majd_2010.pdf.
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La cartographie mobile est un sujet qui se démocratise et gagne en maturité avec la demande croissante des données tridimensionnelles urbaines et périurbaines. La présente thèse aborde la conception d’un système de cartographie mobile terrestre à faible coût avec la particularité d’avoir adapté un scanner laser terrestre pour une utilisation en mode mobile à faible vitesse. Notre objectif n’est pas de rivaliser en termes de performances avec les systèmes commerciaux mais plutôt de s’approprier les compétences scientifiques et technologiques qui permettront de proposer des solutions dans le domaine de cartographie mobile. Les opérations préalables à la mise en route du système, tel que la synchronisation et l’étalonnage sont exposées. Puis, des méthodes basées sur l’ajustement des modèles polynomiaux sont développées pour convenir aux différents trajets parcourus. Les données issues des différents capteurs (GPS/AHRS/TLS) sont testées et filtrées avant de les intégrer dans l’équation de géoréférencement direct. Il en résulte un nuage de points corrigé. Une étude exhaustive sur l’effet des erreurs de chaque capteur sur le nuage de points résultant est établie. La précision théorique est confrontée avec des jeux des données de référence pour valider l’analyse des erreurs. Un appareil photo numérique calibré est intégré dans notre système en tant que capteur de navigation. Une solution photogrammétrique est proposée pour améliorer la précision de la trajectométrie préalablement calculée par l’intégration des données GPS/AHRS. Pour conclure la thèse, une ouverture vers la modélisation géométrique est proposée pour exploiter la géométrie et la précision des données laser terrestres fournies par le système. Le prototype développé permet de fournir des nuages de points d’une précision de l’ordre de 10 à 15cm à une distance moyenne de 20 mMobile mapping technology has been developing with the growing demand of three-dimensional urban and peri-urban data. This thesis approach is based on the design of a low cost terrestrial mobile mapping system with the adaptation of a Terrestrial Laser Scanner for low dynamics. Our goal is not to compete in performance with commercial systems but rather to appropriate scientific and technological skills which will help in proposing solutions in the field of mobile mapping. Necessary operational settings, such as synchronization and calibration are explained. Then, some methods based on the adjustment of polynomial models are developed according to the traveled paths. Data from various sensors (GPS/ AHRS/TLS) are filtered and tested before their integration by direct georeferencing equation in order to produce a correct point cloud. A comprehensive study on the influence of errors of each sensor on the resulting point cloud is established. The theoretical precision is compared with reference data in order to validate the error analyze. A digital calibrated camera is integrated in the system as a navigation sensor. A photogrammetric solution is proposed to improve the accuracy of the orientation and the position calculated by integrating GPS/ AHRS. At the end of this thesis, an approach towards automatic modeling is proposed to make use of the geometry and precision provided by the system. The designed prototype supplies point clouds whose precision is about 10 to15 cm at the average distance of 20 m
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Ozgeneci, Ercin Mehmet. "Mems Sensor Based Underwater Ahrs(attitude And Heading Reference System) Aided By Compass And Pressure Sensor." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614619/index.pdf.
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Attitude and Heading angles are crucial parameters for navigation. Conventional navigation methods mostly uses IMU and GPS devices to calculate these angles. MEMS technology offers small sized, low cost IMU sensors with moderate performance. However, GPS cannot be used in underwater. Therefore, different aiding sensors are used in underwater vehicles in order to increase the accuracy. As the accuracy of devices increases, the cost of these devices also increases. In this thesis, rather than using GPS and high quality IMU sensors, low cost MEMS IMU sensor is used together with a magnetometer and a pressure sensor as aiding sensors. Considering the IMU error model and motion dynamics, two systems are designed and simulated using real data. The results seem to be satisfactory and using pressure sensor as an aiding sensor improves the attitude angles estimation.
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Borasi, Luciano. "Investigation of the Effect of Different “Q&P” Parameters on the Mechanical Properties of AHSS." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-70060.
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In the present study, the influence of the quenching temperature and partitioning conditions (temperature and time) have been investigated on a 0.6%C-1.2%Mn-1.6%Si-1.75%Cr alloy. Maps of hardness, impact toughness and amount of retained austenite have been developed for three quenching temperatures as a function of partitioning temperature and partitioning time. Results demonstrate that, in this material, the carbon depletion of the martensite and the stabilization of austenite can be achieved significantly faster at high partitioning temperatures, promoting higher retained austenite fractions, lower hardness, and maximizing the energy absorbed in a Charpy V‑Notch test. In addition, the effect of the partitioning time was also analysed, presenting different behaviour at high and low partitioning temperatures. Whereas an increment of time at high partitioning temperatures (>400 ºC) leads to an austenite consumption, at low partitioning temperatures it is effective to retain a higher amount of austenite. Furthermore, tensile properties are shown to be better than in conventional alloys utilized in industry. Whilst, for example, the AISI 52100 alloy achieves 2 GPa of tensile strength and 1‑2% of fracture deformation, in the present study the notable combination of 2.5 GPa of tensile strength and 5.7 % of fracture deformation was achieved in samples quenched until room temperature. Untempered martensite transformed during final cooling in samples quenched until higher temperatures was shown to be detrimental for tensile properties. A comparison between the Q&P process and the austempering process on this alloy has been carried out. Results reveal that the quenching and partitioning heat treatment is presented as a promising alternative to reach higher hardness (>700 HV) and similar specific wear rates in dry conditions performing a shorter heat treatment. Finally, a complementary study about the effect of micro-segregation on the Q&P process and an optimization method to minimize the inhomogeneity of the structure by a correct selection of the quenching temperature were established.
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Aykas, Berk. "Evaluation of Edge Fracture in Flanging Advanced High Strength Steel (AHSS) Using the Double Bending Test." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1557210237260137.
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Issa, Danielle Léa. "Testing and prediction of failure of AHSS sheets at Die Radius and Sidewall using novel fracture apparatus." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/50582.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.Includes bibliographical references (p. 109-110).
A new apparatus was constructed to fit the Impact and Crashworthiness Lab's dual actuator custom-made loading frame that has force or position control. The strip is pre-bent into an elbow configuration and fastened by the vertical and horizontal grips. One end of the metal strip is subjected to a predefined constant restraining force, while the other is pulled with a constant velocity to cause a rolling deformation over a prescribed die radius. A series of 40 tests, using TRIP 690 steel, was performed for various combinations of die radius, magnitude of pretension, and die/strip friction. Based on the experimental results, a deformation and failure map was generated, showing ranges of safe forming. Depending on the interplay of different parameters, fracture occurs either on the sidewall or on the die radius, in which case, a close examination of the surface reveals it is slant. Combined theoretical, experimental, and numerical analyses are presented. The present study confirmed previous results published in the literature [1,5] that the pretension needed to fracture a metal strip increases with die radius and tends asymptotically to a constant value. What is new in the present investigation, however, is that this relationship has been quantified for a particular steel of interest for automotive applications. In addition, a method was outlined to predict fracture through finite element simulations, which was lacking in the earlier treatment of a similar problem.
by Danielle Léa Issa.
S.M.
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Gupta, Tanmay. "Predicting and Reducing Springback in Bending of an Aluminum Alloy and Selected Advanced High Strength Steels (AHSS)." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555599407775667.
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Karlsson-Schagerström, Eva, and Ann-Marie Melin. "Kan bedömningsinstrumentet AHA användas för att göra tillförlitliga bedömningar på barn med handdysmeli?" Thesis, Örebro University, Academy of Health Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-2149.
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