Dissertations / Theses: 'Achen'

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Franzke, Jochen. "Netzwerke für Demokratie statt Achsen mit Autokraten." Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2006/807/.

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The German Ostpolitik of the Red-Green government between 1998 and 2005 focused particularly on the autocratic Russia. It mostly ignored the other – democratic – states in Central and Eastern Europe. Since this policy failed to improve the stability in the region, a policy change is necessary. Regional stability can only be based on the equal cooperation of democratic states. Germany should therefore intensify her support for the democratic forces in the region and integrate her policy into a common Ostpolitik within the EU.

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Bain, Kandee. "VARIATION BETWEEN PERIPHERAL AND CENTER ACHENE MORPHOLOGY AND ATTRIBUTES OF ACHENE GERMINATION IN THE INVASIVE SPECIES, CENTAUREA MELITENSIS." CSUSB ScholarWorks, 2015. https://scholarworks.lib.csusb.edu/etd/256.

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Invasive species are often successful and problematic because of their ability to persist in disturbed and undisturbed environments despite weed management practices. Understanding reproduction and dispersal strategies in these species can aid in developing management approaches to help control their spread. Centaurea melitensis, a nonnative invasive with European origins, is found in disturbed areas of southern California. It produces three different types of flower heads that develop at different times and at different locations on the plant during the growing season. The chasmogamous (CH) flower heads are located at the top of the plant, the initial cleistogamous (iCL) heads are located at the base of the plant and at some branch and axillary points, and the final cleistogamous (fCL) heads are located along the stem and at some branch points. This pattern differs from that in Centaurea solstitialis, its most closely related congener, which develops one type of flower head with two morphologically distinct achenes within each flower head: peripheral and center achenes. The overall objective of this study was to examine potential differences between peripheral and center achenes of Centaurea melitensis, including morphological differences in dispersal features, potential differences in response to temperature, tendency to disperse, dormancy and viability. The approach involved selecting whole plants from the field and separating peripheral and center achenes from each of the three head types. Morphological differences were assessed by measuring mass, fruit length, fruit width, pappus length, pappus width, and elaiosome features. Temperature response patterns were evaluated by exposing peripheral and center achenes to temperatures ranging from 5 C to 30 C and measuring germination. Tendency of different achene types to remain in the flower heads was assessed by comparing ratios of peripheral to center achenes in heads immediately after maturation (March to June) to the ratios remaining in heads in early fall (September). Viability and dormancy testing was performed using a cut test and tetrazolium chloride tests in conjunction with germination tests. Results of these studies indicate that peripheral achenes of Centaurea melitensis were lighter and narrower, with shorter pappi and smaller elaiosomes than center achenes. Peripheral achenes responded similarly to their center counterparts in germination response to temperature, but the pattern differed among head types. Broad temperature optima were observed within the fCL and CH heads and a narrow optimum was observed in iCL. There was no evidence that the peripheral achenes remained in the heads longer than the center achenes. Ratios of peripheral to center achenes were 3.8:1 in CH heads, 2.23:1 in iCL heads, and 1.94:1 in fCL heads. Peripheral achenes were more likely to be dormant while maintaining viability than center achenes were. The results of this study, therefore, indicate that peripheral and center achenes of Centaurea melitensis differ morphologically. Dispersal features, such as pappi and elaiosomes, were more highly developed in center achenes than in peripheral achenes, but these differences were not reflected in differences in behavior to the extent we could measure it (i.e., the tendency to remain in heads or the germination responses to temperature). Differences between peripheral and center achenes of Centaurea melitensis trended in the same direction as differences seen in its closely related congener, Centaurea solstitialis, which has center achenes that disperse more readily than peripheral achenes. However, the differences observed in Centaurea melitensis were not as pronounced as those seen in Centaurea solstitialis.

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Achten-Gozdowski, Jennifer [Verfasser]. "Geschichte und Politökonomie deutscher Theatersubventionen / Jennifer Achten-Gozdowski." Hannover : Technische Informationsbibliothek (TIB), 2018. http://d-nb.info/1166271242/34.

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Nachtrab, Timo. "C-Achsen-Transporteigenschaften des intrinsischen Supraleiter-Ferromagnet-Hybrids RuSr2GdCu2O8." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972034870.

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Manku, Ranjit. "Achene variation in bull thistle, Cirsium vulgare (Savi) Ten." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39853.pdf.

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Wipper, Joachim. "Mediale Achsen und Voronoj-Diagramme in der euklidischen Ebene." [S.l.] : Universität Stuttgart , Fakultät Mathematik, 1997. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB7899043.

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Völker, Katrin. "Putzeffizienz neuer Handzahnbürsten unter Verwendung eines 4-Achsen Roboters." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-56145.

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Pilger, Christian. "Galanthamin als AChE-Inhibitor Beiträge zum rationalen Wirkstoffdesign /." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961546743.

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9

Miller, David J. "The Ai-Achan narrative a case study in Biblical historiography /." Theological Research Exchange Network (TREN), 1987. http://www.tren.com.

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Russell, Wayne Shaun. "The biological significance of AChE secretion by Nippostrongylus brasiliensis." Thesis, Imperial College London, 1999. http://hdl.handle.net/10044/1/8465.

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11

Henrion-Dourcy, Isabelle. "Ache Lhamo : Jeux et enjeux d'une tradition théâtrale tibétaine." Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211111.

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L'objet de cette thèse est une monographie du théâtre traditionnel tibétain, ou ache lhamo, souvent appelé lhamo tout court, tel qu'il était joué à l'époque pré-moderne (antérieure à 1950) et tel qu'il est encore joué actuellement en Région Autonome du Tibet (République Populaire de Chine) et dans la diaspora tibétaine établie en Inde et au Népal. Comme la plupart des théâtres d'Asie, il est un genre composite :à la fois drame à thématique religieuse (issue du bouddhisme mahāyāna), satire mimée, et farce paysanne, il comprend de la récitation sur un mode parlé, du chant, des percussions, de la danse et des bouffonneries improvisées, ainsi qu'un usage de masques et de costumes flamboyants, qui tranchent avec la sobriété absolue des décors (la scène est vide) et de la mise en scène. Bien qu’il ait été encouragé et financé par le gouvernement des Dalai Lama, de grands monastères et des familles aristocratiques, c’est un théâtre avant tout populaire, et non pas réservé à une élite lettrée. Cette étude a circonscrit à la fois le contenu, le rôle social, le langage artistique et les implications politiques du théâtre dans la civilisation tibétaine.

La méthodologie a été composée en combinant les apports et réflexions critiques de trois disciplines :l'ethnologie, la tibétologie et les études théâtrales. L'approche est fondamentalement ethnologique, en ce que la production des données repose sur une immersion de plus de deux ans parmi des acteurs de théâtre de la Région Autonome du Tibet (1996-1998) et de près d'un an parmi ceux de la diaspora d'Asie du Sud (1998-2000). Elle l’est aussi en ce que l’intention a été de constituer une intelligibilité englobante pour l'ache lhamo, c'est-à-dire de mettre au jour l'intrication des dimensions culturelle, sociale, politique, économique, rituelle et symbolique de la pratique théâtrale. L’une des contributions principales du travail est d’étoffer l’ethnologie régionale du Tibet central, mais ses conclusions et son esprit critique le placent également dans la liste déjà importante des travaux consacrés à l'invention des traditions. La tibétologie a fourni le cadre interprétatif fondamental des données recueillies. Une importance très grande a été accordée à l'histoire du pays ainsi qu'à la philologie et aux terminologies vernaculaires particulières au théâtre. L’étude s’inscrit dans l’un des courants novateurs de la tibétologie, privilégiant les aspects non plus religieux et politiques de cette civilisation, mais sa partie « populaire » et anthropologique, mettant au premier plan l’analyse des pratiques et non celle des doctrines. Des sources écrites (textes pré-modernes et sources secondaires de folkloristes tibétains et chinois) ont été intégrées aux observations. En ce qui concerne la troisième approche méthodologique, cette étude ne s'inscrit ni dans le courant des « performance studies » de Richard Schechner, ni dans l'anthropologie théâtrale d’Eugenio Barba, ni dans l'ethnoscénologie telle qu'elle est défendue par Jean-Marie Pradier, mais plutôt dans l'anthropologie du théâtre, au sens d'étude interprétative et multidimensionnelle, utilisant les référents établis de l'anthropologie et les savoirs indigènes pour décrire une expression culturelle déterminée et reconnue comme un genre à part entière, le théâtre.

Les résultats sont présentés en trois parties, qui peuvent être résumées de manière lapidaire par trois adjectifs :culturelle, sociologique, artistique. La première partie, intitulée "Le cadre culturel du lhamo avant 1959", est consacrée au contexte (historique, religieux et littéraire) dans lequel le théâtre est inscrit, ainsi qu’aux textes (leur contenu, leurs modalités de composition et de transmission) qui révèlent l'imaginaire propre du théâtre. La deuxième partie est une analyse de "L'ancrage sociologique du lhamo". Les conditions matérielles des représentations y sont examinées :les divers types de troupes, leur organisation interne, le statut social des acteurs, l'inscription de la pratique du théâtre dans le système socio-économique pré-moderne, et les rapports d'obligations tissés entre acteurs et seigneurs, ainsi qu'entre acteurs et commanditaires des représentations. La dernière partie, "Art et savoirs des acteurs", jette un éclairage sur la matière vive du lhamo. Elle rend compte des conceptions, valeurs, plaisirs et difficultés de ceux qui pratiquent cette forme d'art. Les divers registres de leur discipline sont analysés en détail :costumes, masques, gestuelle, chant, accompagnement musical (percussions) et sentiments exprimés. L'appréciation qui en est faite par le public est aussi consignée. Au cœur de cette partie se trouve une réflexion sur la nature rituelle et non rituelle du lhamo, et sur les liens éventuels de ce dernier avec d'autres activités religieuses, telles la possession. Les dernières pages de la thèse constituent un épilogue, qui fait le point sur la situation contemporaine, donc les implications politiques, du théâtre des deux côtés de l'Himalaya.

L'image anthropologique du lhamo qui a pu être dégagée de ces trois volets d'analyse le fait apparaître comme essentiellement ambivalent :le lhamo est un théâtre de paradoxes. À l'image de la civilisation tibétaine, il est composite et cohérent à la fois. Sa cohérence réside dans son ambivalence :il traverse et relie des aspects contrastés de la culture. Il introduit du jeu entre les polarités que Tibétains et tibétologues établissent parfois un peu trop à la hâte entre culture savante et culture populaire, écriture et oralité, éléments exogènes et apports autochtones, bouddhisme et cultes qui ont précédé son implantation, aspiration religieuse et intérêts mondains, spécialistes rituels et bénéficiaires qui les rémunèrent. Combinant fonction pédagogique et fonction rituelle, sacré compassé du texte et irrévérence grivoise des improvisations, le lhamo correspond aussi très bien à la manière dont les théâtrologues appréhendent le théâtre :comme un objet curieux, créé par les hommes et qui pourtant ne cesse de les intriguer, comme s'il était venu d'ailleurs.
Doctorat en Sciences politiques et sociales
info:eu-repo/semantics/nonPublished

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Pettersson, Siri. "Makrofossilanalys som ekologiskt verktyg : En metodutvärdering." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-321511.

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Approximately 50 percent of all endangered species in Scandinavia are associated with old agricultural landscapes. During the agricultural industrialization of the past century the traditional practices and methods that created these environments have been phased out. This has brought on a serious decline and fragmentation of biomes that many endangered species depend on. Knowledge of traditional agricultural landscapes and their species dynamics is needed to make well informed decisions regarding their care and restoration. One way to acquire such knowledge is to study fossil plant remnants from old agricultural contexts. In this study sub-fossil Cyperaceae achenes were analyzed in an attempt to identify them. The achenes had been preserved in three Iron Age wells (80-980 AD) at the Gilltuna settlement in central Sweden and were found during an archeological investigation in 2010. The purpose of this study was to identify the achenes to species level, make conclusions about the ecology of the surrounding landscape, and construct simple species identification key as well as evaluate archaeobotany as an ecological tool. The identification attempt resulted in 14 determined species, which were in consistency with previous landscape analyses made using ecological species distribution. The resulting identification key is a suggestion, to be expanded in the future. This method can undoubtedly provide further knowledge of prehistoric and historical biomes, but in order to draw useful conclusions the identification technique further as well as knowledge of present regional ecology must be developed, especially concerning different Cyperaceae species‟ response to different kinds of stress.

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Höhn, David. "Der Zusammenhang zwischen Hirnmorphologie, Therapieantwort und HPA-Achsen Aktivität bei der Depression." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-86915.

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Alxneit, Heiko [Verfasser]. "Optimierung des Übertragungsverhaltens konischer Außenstirnräder mit kreuzenden Achsen / vorgelegt von Heiko Alxneit." Stuttgart : IKTD, 2010. http://d-nb.info/1005389861/34.

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Croset, Patricia. "Décomposition dynamique et parallélisme multi-t^ache en analyse de structure." Toulouse, INPT, 1989. http://www.theses.fr/1989INPT033H.

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L'utilisation de calculateurs paralleles est aujourd'hui essentielle pour aborder le traitement de structures complexes de grande taille. Une etude du comportement informatique de la methode des sous-structures illustre l'interet des methodes de decomposition dans le cadre du calcul parallele. Une technique de sous-structuration dynamique specifique a une exploitation des calculs en environnement multi-processeurs a ete developpee. Des experimentations realisees sur un cray-2 mettent en evidence l'interaction profonde entre algorithme et machine cible et refletent l'influence des contraintes d'implantation qui penalisent fortement les performances. Diverses solutions susceptibles de reduire le caractere machine dependant de la strategie de mise en uvre et de minimiser l'impact negatif d'une execution en environnement multi-utilisateur ont ete proposees. Enfin, une etude theorique de l'adequation de ce type d'algorithmes aux caracteristiques des architectures a haut degre de parallelisme, illustree de divers exemples de mise en uvre, montre que cette classe de calculateurs pouvait exploiter efficacement le parallelisme intrinseque a ces methodes de decomposition

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Yasapala, Sumana Nilahthi. "Reactivation of Organophosphorus agent inhibited-human acetylcholinesterase." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/2169.

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Organophosphorus compounds (OPs) are used as pesticides, e.g. parathion, which is converted in the body to paraoxon, and chemical warfare nerve agents, such as sarin, soman, cyclosarin, VX, and tabun. Even small amounts of OP exposure can be fatal, depending on the toxicity of the compound. Great stocks of highly toxic chemical warfare nerve agents exit around the world and are considered a serious threat to national security and international stability. OPs exert their toxicity by covalent irreversible inhibition of acetylcholinesterase (AChE) that prevents the enzyme from hydrolyzing acetylcholine (ACh), a neurotransmitter in the central and peripheral nervous systems (CNS and PNS). Therefore, ACh accumulates in the cholinergic synapses throughout the body, which results in overstimulation of the ACh receptors. Removal of the phosphyl moiety from the OP-bound AChE active site has been a promising method to restore AChE’s catalytic activity. However, a secondary process called aging also occurs in the OP-AChE complex. Once aging occurs, currently available oximes are ineffective in removing the phosphyl moiety from the enzyme’s active site, and hence are ineffective as antidotes against the aged enzyme. Several families of alkylating and acylating agents including several classes of agents that combine alkylating moieties with known active site or peripheral cite (PAS) binding motifs were synthesized and evaluated. The general aim of the research was that successful alkylation or acylation of the phosphonate monoanion of aged AChE would produce neutral phosphyl complexes that would either spontaneously reactivate or would be reactivatable in the presence of oxime antidotes. Methoxylamine analogs of the oxime antidote 2-PAM were synthesized with the aim that methyl transfer to the aged AChE adduct would produce a neutral phosphyl AChE adduct simultaneously with 2-PAM in situ, and subsequent 2-PAM nucleophilic attack would reactivate the newly formed neutral phosphyl-AChE adduct. However, none of these 2-PAM analogs resurrected the activity of aged AChE. Another strategy for resurrecting the activity of aged AChE utilizes N-methylpyridiniums that are substituted at the 2-position with a beta-lactam moiety. For these compounds, opening of the electrophilic beta-lactam unmasks a nucleophilic amidine function which could putatively attack at phosphorus to expel the free enzyme. For this class of agents, only the active site directed compound that possessed the 5-CF₃ substituent showed possible resurrection of the activity of aged AChE, though activities in both the control and treated samples were low. Methyl transfers are common in Nature, and the natural transfer agent is S-adenosylmethionine, a sulfonium methyl donor. Consequently, the array of sulfonium compounds were evaluated on the expectation that they would bind to the AChE active site and transfer a methyl group to the phosphonate monoanion of the aged enzyme. Though high-affinity binding was noted for these compounds, none of these resurrected the activity of the aged AChE complex. Finally, several selected agents were evaluated on reactivating the initial OP-AChE complex before aging has occurred. It was observed that degraded samples of selected inhibitors are capable of reactivating initial complexes of sarin and soman inhibited AChE at low concentration that is an important character of efficient reactivators. However, the structure of reactivator is still unknown. Two major challenges still face researchers in the quest to design effective medicinal agents for counteracting poisoning by AChE-inhibiting nerve agents. The first is that there is no universal oxime antidote. Oximes that are effective against certain nerve agents are ineffective against others. The second is that, despite extensive efforts that span two generations, aged phosphyl-AChE adducts have never been reactivated. However, given the powerful tools of modern structural biology, medicinal chemistry and molecular biology, there is still hope that these considerable challenges can be met.

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Traut, Christopher Verfasser], and Hansgeorg [Akademischer Betreuer] [Binz. "Geometrische Auslegung der Mikrogeometrie konischer Außenstirnräder mit kreuzenden Achsen / Christopher Traut ; Betreuer: Hansgeorg Binz." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2019. http://d-nb.info/1201345995/34.

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Traut, Christopher [Verfasser], and Hansgeorg [Akademischer Betreuer] Binz. "Geometrische Auslegung der Mikrogeometrie konischer Außenstirnräder mit kreuzenden Achsen / Christopher Traut ; Betreuer: Hansgeorg Binz." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2019. http://d-nb.info/1201345995/34.

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Roessler, Eva-Maria. "Aspectos da gramatica ache : descrição e reflexão sobre uma hipotese de contato." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/269129.

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Orientador: Maria Filomena Spatti Sandalo
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
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Resumo: Este trabalho é um estudo piloto de alguns aspectos fonológicos e morfológicos da língua achê, uma língua indígena falada por aproximadamente 300 falantes fluentes na região oriental do Paraguai. O trabalho apresenta um estudo fonológico, que inclui a descrição dos segmentos vocálicos e consoantais, como também de aspectos suprassegmentais como o espraiamento de nasalidade. Além disso, discute-se a estrutura silábica, o acento lexical e a estrutura da palavra mínima do achê. A segunda parte apresenta uma descrição da marcacão de pessoa/número, de tempo-aspecto-modo, da construção passiva e também das categorias lexicais da língua achê. É importante destacar que o trabalho tem um segundo objetivo: contextualizar estas descrições gramaticais em um debate sociolingüístico. Durante os últimos dois séculos, e até hoje, a literatura histórica, antropológica e lingüística apontam para a hipotése de o achê ser uma língua de contato baseada no léxico da língua guarani. Como o meu trabalho aborda a questão do contato lingüístico a partir de uma visão interdisciplinar, informações etnográficas e históricas relevantes para o entendimento da possível gênese da língua achê são incluídas. Apresento dados lingüísticos, resultados da minha pesquisa de campo, que podem contribuir para esta discussão. Observo que. há mudanças, essencialmente no subsistema morfossintático, que podem ser consideradas abruptas, e, portanto, podem indicar uma transmissão lingüística nãolinear. O subsistema morfossintático conta com recursos morfológicos reduzidos quando comparado com a possível língua base - o guarani do Paraguai. Estes recursos, além disso, passaram por mudanças, tanto na sua forma fonológica, quanto na sua função. As alterações na função, que em muitos casos são caracterizadas por uma ampliação de funções morfossintáticas e semânticas, podem ser entendidas como resultado de processos de analogia e reinterpretação.
Abstract: This work Is a pilot study of some aspects of phonology and morphology of Aché, an indigenous language spoken by approximately 300 fluent speakers in the oriental region of Paraguay. It presents a phonological study of the phonemic inventory as well as a study of suprasegmental phenomena such as nasalization, stress, syllable structure, and some considerations about minimal word constraints. In the second section of the descriptive part, I outline aspects of person and number agreement, tense-aspect-mood marking, followed by a description of passive constructions and a discussion on lexical categories of the Achá language. The preceding grammatical description is particularly relevant for a wider sociolinguistic discussion of language genesis and evolution. The historical, anthropological and linguistic literature of the past two centuries suggests the hypothesis that the Aché language might be a contact language based on the lexicon of Paraguayan Guarani. My work approaches this hypothesis from an interdisciplinary standpoint, and includes some ethnographic and historic information crucial for the understanding of a possible genesis of the Aché language. In the final section I review linguistic data - the results of my field research - that can contribute to that discussion. Specifically, inside the morphosyntactic subsystem of the Aché grammar, I observe changes that can be considered abrubt and therefore the result of possible non-linear transmission. The morphosyntactic subsystem contains reduced flexional morphemes if compared to the hypothesized lexifier language - Paraguayan Guarani. The remaining flexional morphemes changed both their phonological structure and their grammatical functions. In grammatical terms, the changes can be characterized as amplifications of morphosyntactic and semantic function and might be possibly understood as outcome of processes such as analogy and reinterpretation.
Mestrado
Mestre em Linguística

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Previdi, Daniel. "Estudos sobre a síntese de derivados de cyclophostin inibidores da acetilcolinesterase (AChE)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-31072014-155044/.

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Bactérias do gênero Streptomyces produzem diversos tipos de butirolactonas, cujos exemplos importantes são o cyclophostin, os compostos da família cyclipostin e as -butirolactonas autorreguladoras. O cyclophostin é um potente inibidor da enzima acetilcolinesterase, os compostos da família cyclipostin são inibidores de lipases, enquanto que as -butirolactonas autorreguladoras estimulam a produção de antibióticos em culturas de bactérias do gênero Streptomyces. Neste trabalho foram realizados estudos para a obtenção de derivados do cyclophostin e de derivados das -butirolactonas autorreguladoras. Para isso foram propostos dois planejamentos sintéticos mostrados nos esquemas 8 e 10 (Seção: III. Planejamento Sintético). Os estudos realizados de acordo com o planejamento sintético mostrado no esquema 8 tiveram como etapa chave uma reação de Barbier entre a butenolida 43, diversos aldeídos e um metal (zinco ou índio), em meio aquoso. Apesar dessa reação ser bem conhecida, em nenhum dos testes realizados foram obtidos os compostos de interesse, sendo que o principal produto obtido foi o composto 56, proveniente da redução da butenolida 43. Diante disso, foi proposta uma explicação para esses resultados com foco em possíveis mecanismos para a reação de Barbier, comparando com substratos similares a butenolida 43 que foram utilizados com sucesso na reação de Barbier. Os estudos realizados de acordo com o planejamento sintético mostrado no esquema 10 forneceram resultados satisfatórios. A reação entre o monóxido de butadieno e diferentes -cetoésteres possibilitou a obtenção de -butirolactonas 2,3-dissubstituídas na forma de um único diastereoisômero e -butirolactonas 2,4-dissubstituídas na forma de mistura de diastereoisômeros (mostradas na Tabela 7). Através das análises de NOEDiff-RMN, juntamente com dados da literatura e cálculos computacionais das constantes de acoplamento, foi possível determinar a configuração relativa dos grupos substituintes das -butirolactonas 2,3-dissubstituídas como sendo trans. Com três -butirolactonas 2,3-dissubstituídas foram realizadas reações de ozonólise, com clivagem redutiva do ozonídeo por boro-hidreto de sódio, fornecendo três compostos na forma de misturas de diastereoisômeros com estruturas análogas ao IM-2 e às virginiae butanolidas (mostrados na Tabela 8). Com a -butirolactona 54a foi realizada a formação do enol-fosfato 55a, utilizando dietil-clorofosfato como agente de fosforilação (reação mostrada no Esquema 23). Com este composto foram realizadas reações de ozonólise, utilizando boro-hidreto de sódio ou sulfeto de dimetila para a clivagem do ozonídeo, porém em nenhuma dessas tentativas foram obtidos resultados satisfatórios (reação mostrada no Esquema 24). Outras tentativas foram realizadas com intuito de obter derivados do cyclophostin utilizando outros materiais de partidas, porém todas as tentativas falharam, seja na etapa de ozonólise ou na etapa de ciclização para a formação do esqueleto de enol-fosfato cíclico presente no cyclophostin. Apesar dos resultados insatisfatórios descritos acima, alguns intermediários obtidos foram submetidos a um ensaio biológico em que foi monitorada a produção do antibiótico nigericina em culturas de actinobactérias do gênero Streptomyces. Nesse ensaio biológico foram obtidos resultados satisfatórios, sendo que alguns compostos estimularam a produção do antibiótico nigericina, outros inibiram e outros não mostraram efeitos significativos, indicando a existência de uma relação estrutura-atividade dos compostos testados.
Bacteria of the genus Streptomyces produce many kinds of butyrolactones; e.g., cyclophostin, compounds belonging to the cyclipostin family, and -butyrolactones autoregulators. Cyclophostin is a potent inhibitor of the enzyme acetylcholinesterase, the compounds of the cyclipostin family inhibit lipases, and -butyrolactones autoregulators stimulate antibiotics production in bacterial cultures of the genus Streptomyces. This work aimed to obtain cyclophostin derivatives and -butyrolactones autoregulators derivatives via two proposed synthesis designs as illustrated in schemes 8 and 10 (Section: III. Synthetic Planning). The key step in the design shown in scheme 8 consisted of a Barbier reaction between butenolide 43, several aldehydes, and a metal (zinc or indium), in aqueous medium. Although this reaction has long been known, the tests performed here did not afford any of the target compounds. The main product was compound 56, arising from the reduction of butenolide 43. An explanation for the results was proposed on the basis of possible mechanisms for the Barbier reaction and of comparison with similar compounds of butenolide 43, which have been successfully used in the Barbier reaction. Studies carried out according to the synthesis design presented in scheme 10 provided satisfactory results. The reaction between butadiene monoxide and various -ketoesters furnished 2,3-disubstituted--butyrolactones as a single diastereoisomer and 2,4-disubstituted--butyrolactones as a mixture of diastereoisomers (shown in Table 7). NOEDiff-NMR analysis together with literature data and computer calculations of coupling constants helped to determine the relative configuration of the 2,3-disubstituted--butyrolactones substituent groups as trans. Three 2,3-disubstituted--butyrolactones ozonolysis reactions were conducted by reductive cleavage of the ozonide with sodium borohydride, which afforded three compounds as diastereoisomers mixtures bearing structures analogous to those of IM-2 and virginiae butanolides (shown in Table 8). Reaction of -butyrolactone 54a with diethyl chlorophosphate as phosphorylating agent produced the enol-phosphate 55a (reaction shown in Scheme 23). Ozonolysis reactions of this compound using sodium borohydride or dimethyl sulfide to cleave the ozonide did not provide satisfactory results (reaction shown in Scheme 24). Other attempts to achieve cyclophostin derivatives using different starting materials failed during the ozonolysis step or the cyclization to form the cyclic enol-phosphate skeleton present in cyclophostin. Despite the poor results described above, some of the intermediates were submitted to a biological assay to monitor production of the antibiotic nigericin in Streptomyces actinomycetes cultures. Some of the tested compounds stimulated, others inhibited, and others did not affect nigericin production, indicating existence of a structure-activity relationship.

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Kwasnieski, Ophélie. "Etude théorique de la réactivation de l’acétylcholinestérase (AChE) inhibée par le tabun." Paris 6, 2010. http://www.theses.fr/2010PA066461.

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L’AChE, enzyme clé pour la neurotransmission, est la cible des neurotoxiques organophosphorés utilisés comme agents de guerre tels que le tabun. En inhibant irréversiblement l’AChE, ces neurotoxiques peuvent entraîner la mort par asphyxie. Des antidotes à ces organophosphorés existent : il s’agit d’oximes, qui sont des nucléophiles puissants. Malheureusement, aucune oxime à l’heure actuelle n’est capable de restaurer l’activité de l’AChE inhibée par le tabun. C’est pourquoi nous nous sommes particulièrement intéressés au complexe AChE-tabun en utilisant une méthodologie hybride QM/MM. Nous avons ainsi défini notre modèle théorique sur l’acétylcholine, substrat naturel de l’AChE, ce qui nous a permis de mettre en évidence la grande flexibilité de l’AChE et la difficulté de la traiter en chimie théorique quantitativement. Nous nous sommes ensuite penchés sur l’inhibition de l’AChE par le tabun pour montrer l’influence de la structure du tabun sur sa réactivité dans le site actif. Notamment le rôle stérique du groupement N-diméthyle a été souligné. Enfin, nous avons abordé la réactivation du complexe AChE-tabun. L’influence du mécanisme (une ou deux étapes) a permis d’expliquer la difficile réactivation du complexe AChE-tabun. Un nouveau réactivateur a pu être conçu à partir de ces informations, synthétisé et testé in vitro. Ce réactivateur n’est malheureusement pas efficace contre le complexe AChE-tabun du fait de paramètres physico-chimiques que nous ne pouvons pas prendre en compte d’un point de vue théorique. Notre travail a donc permis de mettre au point un modèle théorique efficace pour traiter les interactions de l’AChE avec différents substrats.

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McDonald, Heather L. "Arthritis, aches and pains, and arthritis services : experiences from within an urban First Nations community." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/35987.

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This dissertation explored the experiences of health and healthcare reported by members of an urban First Nations community who had arthritis and the ways in which arthritis health services were aligned (or not aligned) with these experiences. Using a community-based, participatory design, grounded in decolonizing methodologies and ethnographic methods, this study had two research fields that related to the research questions. Study activities in one research field included intensive immersion in a First Nations community over a period of three years, and interviews with 24 community members. In the second field, which included three arthritis services settings, study activities involved approximately 100 hours of immersion and interviews with 30 healthcare professionals. The analysis of community-based data revealed that experiences of ongoing arthritis/pain and social suffering were inextricably linked to and underpinned by the social and historical context of life in the community. Most, but not all, community participants were reluctant users of health services, largely related to prior negative experiences utilizing health services. The organization and delivery of arthritis health services, shaped by dominant healthcare discourses, were not well aligned with the experiences of First Nations peoples with arthritis; rationing and biomedical discourses limited the ability of the system to be responsive to social contexts, and culturalist and self-management discourses served to deflect healthcare professionals’ attention away from the role that social and material life conditions played in shaping the experiences of First Nations individuals living with arthritis. Amongst arthritis health services leaders and professionals there was a sincere desire to provide effective, quality care to all people with arthritis. Creating more opportunities for social/critical knowledge to be present in health services settings could go a long way towards improving the alignment of arthritis services with arthritis experiences of First Nations peoples.

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Fix, Martin. "Textrevisionen in der Schule : prozessorientierte Schreibdidaktik zwischen Instruktion und Selbststeuerung ; empirische Untersuchungen in achten Klassen /." Baltmannsweiler : Schneider-Verl. Hohengehren, 2004. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015685309&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Lee, Hing Cheong. "The transcriptional regulation of collagen-tailed (ColQ) subunit of acetylcholinesterase (AChE) in muscles /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202003%20LEE.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.
Includes bibliographical references (leaves 132-154). Also available in electronic version. Access restricted to campus users.

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Paula, Alexandre Adriano Neves de. "Estudos de estrutura eletrônica e análise multivariada de candidatos a inibidores da AChE." reponame:Repositório Institucional da UnB, 2009. http://repositorio.unb.br/handle/10482/7408.

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Tese (doutorado)—Universidade de Brasília, Instituto de Física, 2009.
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Neste trabalho apresentamos um estudo sobre novos candidatos a inibidores da acetilcolinesterase obtidos a partir de um lipídio fenólico não-isoprenóide do líquido da casca da castanha de caju (Anacardium occidentale). Foram investigados, através do cálculo de estrutura eletrônica, dois Padrões de Estrutura Molecular (PEM) derivados do cardanol: um composto por 15 moléculas construídas a partir do PEM2 com os grupos substituintes metila, acetila, N,N-dimetilcarbamoíla, N,N-dimetilamina, N,N-dietilamina, pirrolidina, piperidina e N-benzilamina e outro composto por 20 moléculas derivadas do PEM3 substituindo fragmentos que fariam interação com a serina200 (S200) e do triptofano84 (W84) pelos anéis de 5 e 6 membros. As propriedades eletrônicas, tais como energias (HOMO-1, HOMO, LUMO, LUMO+1 e derivados), distribuições de cargas (anel benzênico, oxigênio 56, carbono 11 e nitrogênio das aminas secundárias) entre outras, foram obtidas usando os níveis de cálculos RHF e B3LYP com os conjuntos de funções de base 6-31G, 6-31G(d), 6-31+G(d),6-311G(d,p) 6-311G(2d,p) e 6-311+G(2d,p). Os resultados obtidos revelam que os derivados do PEM2, formadas com as substituições acetila, N,N-dimetilformamida, N,N-dimetilamina e pirrolidina, são as estruturas que mais se correlacionam com o fármaco amplamente utilizado como inibidor da acetilcolinesterase contra a doença de Alzheimer (rivastigmina). Com relação aos derivados do PEM3 os compostos que melhor se correlacionam com a rivastigmina foram as estruturas PEM3-01, PEM3-03, PEM3-06 e PEM3-19. _________________________________________________________________________________ ABSTRACT
In this work is presented a study about new potential candidates of acetylcholinesterase (AChE) inhibitors designed from cardanol, a non-isoprenoid phenolic lipid of cashew Anacardium occidentale nut-shell liquid. From electronic structure calculations were investigated two molecular structure models (PEM): the first is formed by 15 molecules derivatives from the cardanol (PEM2) using the groups methyl, acetyl, N,N-dimethylcarbamoyl, N,N-dimethylamine, N,N-diethylamine, piperidine, pyrrolidine, and N,N-methylbenzylamine; while the second is formed by 20 molecules derivatives from cardanol (PEM3) substituting the fragments that interacts with ser200 and W84 sites by rings with 5 and 6 species. Electronic properties, such as, energies (HOMO, LUMO, HOMO-1, LUMO+1 and derivatives) and charge distributions were performed at RHF and B3LYP levels using 6-31G, 6-31G(d), 6-31+G(d),6-311G(d,p) 6-311G(2d,p) and 6-311+G(2d,p) basis functions. The obtained results indicated that the PEM2 structures with substitution by acetyl, N,Ndimethylcarbamoyl, N,N-dimethylamine, and pyrrolidine groups PEM3 were better correlated to rivastigmine and represent possible AChE inhibitors against Alzheimer disease. In relation to PEM3 molecular structure model the compounds that presented a significant contribution in the recognition by AChE were PEM3-01, PEM3- 03, PEM3-06 e PEM3-19.

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Deason, Charlotte Cecille. "Harold Pinter's use of the five senses in The caretaker and A slight ache." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Chan, Tay On Kou Alexandra Valeria. "Replanteamiento de la identidad visual del restaurante Ache a partir de su dimensión cultural." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/657155.

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En esta investigación se encontró un problema de comunicación visual en el restaurante Ache, donde se identificó la falta de elementos gráficos que logre identificar al restaurante de cocina nikkei a partir de su dimensión cultural. Se identificó que este problema de comunicación visual solo se podía resolver mediante el diseño gráfico, ya que pertenece precisamente al área identitaria. Además, este proyecto muestra una justificación cultural y práctica donde se identificarán aspectos esenciales para el replanteamiento de la identidad del restaurante para que logre transmitir su esencia como marca al consumidor.También, se realizó una encuesta a un grupo de personas que consumen comida nikkei y se entrevistó a dos expertos que han creado y rediseñado proyectos de identidad visual de restaurantes nikkeis y otros rubros de comida. Adicionalmente, se utilizó la metodología de trabajo del doble diamante para realizar el proceso de elaboración de la gráfica visual.Los principales resultados que se pudo obtener mediante la propuesta de diseño fueron positivos, ya que los usuarios consideraron que la nueva gráfica sí reflejaba el rubro de comida que ofrecían. Igualmente, el logo lo relacionaban con la cultura nikkei, la carta lo consideraban claro y directo, las imágenes ayudaban a entender el producto a consumir y el empaque les parecía innovador y diferente generando una experiencia única.
In this research, a visual communication problem was found in the Ache restaurant, where the lack of graphic elements that could identify the Nikkei cuisine restaurant from its cultural dimension was identified. It was identified that this visual communication problem could only be solved through graphic design, since it belongs precisely to the identity area. In addition, this project shows a cultural and practical justification where essential aspects will be identified for the rethinking of the identity of the restaurant so that it can transmit its essence as a brand to the consumer.Also, a survey was made to a group of people who consume Nikkei food and two experts who have created and redesigned visual identity projects for Nikkei restaurants and other food items were interviewed. Additionally, the double diamond methodology was used to carry out the process of elaboration of the visual graphics.The main results obtained through the design proposal were positive, since the users considered that the new graphics did reflect the food offered. Likewise, the logo was related to the Nikkei culture, the menu was considered clear and direct, the images helped to understand the product to be consumed and the packaging seemed innovative and different, generating a unique experience
Trabajo de Suficiencia Profesional

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28

Nikjoo, Dariush. "Design and Synthesis of a Small Set of Thiourea-based Compounds as Inhibitors of AChE1 from Mosquitoes." Thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-92551.

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Niebler, Julia. "Die Stärkung der Regionalfensterprogramme im Privaten Rundfunk als Mittel zur Sicherung der Meinungsvielfalt durch den Achten Rundfunkänderungsstaatsvertrag /." Frankfurt am Main : Lang, 2009. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017070441&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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30

Michalowski, Victoria Izabela. "Associations between perceived support in older adult marriages and dyadic co-variations in momentary affect and aches." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54785.

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Spousal support within marriage may be particularly important in old age when spouses become more likely to rely on each other’s help. However, spousal support does not have to be unanimously positive. In fact, very little is known about co-variations in spousal affect and aches as couples engage in their daily routines and environments. Up to 27 simultaneous, momentary assessments from 49 older adult married couples (M age = 72 years (60-83); M relationship duration = 42 years) were used taking into account the perspective of both partners. This research shows that social support within marriage was associated with reduced overall levels of negative affect but unrelated to positive affect. Interestingly, high spousal support was both associated with reduced overall negative affect means but also with an increased co-variation in negative affect between partners. No similar co-variations were observed for aches and positive affect. Spousal support may be a double-edged sword; it is associated with reduced overall negative affect, but it may also lead to more permeable boundaries between spouses that seem to be specific to negative affect.
Arts, Faculty of
Psychology, Department of
Graduate

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31

Schmitt, Wolfgang. "Transport- und Hochfrequenz-Verhalten von supraleitenden c-Achsen orientierten (SE)Ba 2 Cu 3 O 7-[delta] -Filmen /." Karlsruhe : Forschungszentrum Karlsruhe GmbH, 2000. http://swbplus.bsz-bw.de/bsz087775999abs.htm.

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32

Andrews, Melanie Charlotte. "Characterisation of acetylcholinesterase (AChE) in aphids and mutations associated with resistance to carbamate and organophosphorus insecticides." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419736.

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Böhme, Carsten [Verfasser], Katja [Gutachter] Petrowski, and Hendrik [Gutachter] Berth. "Vergleich der Hypothalamus-Hypophysen-Nebennieren-Achsen-Reaktivität bei Panikstörung und Posttraumatischer Belastungsstörung / Carsten Böhme ; Gutachter: Katja Petrowski, Hendrik Berth." Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://d-nb.info/1227196512/34.

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Prinz, Michaela [Verfasser], and Ulrike [Akademischer Betreuer] Holzgrabe. "Inhibitoren der AChE, BuChE und der Amyloid-beta-Aggregation vom Pyridylenhydrazon-Typ / Michaela Prinz. Betreuer: Ulrike Holzgrabe." Würzburg : Universitätsbibliothek der Universität Würzburg, 2012. http://d-nb.info/1027949126/34.

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Silva, Suzana Vieira. "Estudo semiempirico da inibi??o da AChE por policet?deos extra?dos da esponja marinha Plakortis angulospiculatus." Universidade Federal Rural do Rio de Janeiro, 2009. https://tede.ufrrj.br/jspui/handle/jspui/2002.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior. CAPES
The Evil of Alzheimer is a disease neurodegenerativa that reaches to the cognitive functions among them the memory, attention and learning. The main strategy used for his/her treatment is addressed in the search of improving the hipofun??o colin?rgica, inhibiting the enzyme acetylcholinesterase, so that the acetylcholine can stay more available in the rift sin?ptica for the accomplishments of the sinapses, since this enzyme has the hidrolisar function the acetylcholine. The nature offers an enormous variety of substances used as f?rmacos and the sea sponges has been demonstrating be rich in these substances. They were extracted of the sponge Plakortis angulospiculatus three polyketides that through the method Ellman demonstrated activity anticolinester?sica. Through techniques of Molecular Modelling, calculations semiempiricos were accomplished using the method PM3 to analyze the geometric interactions and energies involved in the compound polyketidesacetylcholinesterase with the objective of analyzing a possible use of these as f?rmacos for the Evil of Alzheimer. As if he/she didn't know the state in that the ranch would be (with Ser200 and neutral His440 or no) in the moment of the interaction, calculations were accomplished for the three polyketides in both ranches. Studies with inhibitors already known tacrina and huprina X (both neutral one and protonadas) they were also accomplished at both ranches in order to comparison. Resulted obtained he in this work showed the reliability of the employed method, likewise as values of favorable entalpia for the formation of all the compounds independent pollyketide-acetylcholinesterase of the ranch. It was observed by the energy values a preference when the same ones if they found in the ranch protonado diferencialmente of the inhibitors tacrina and huprina X that independent of his/her state (protonados or no) they showed better interaction for the neutral ranch. The calculations accomplished for the tacrina demonstrated that even after optimization the main interactions described already by the literature stayed and that possibly she meets protonada inside of the seen ranch the values of energy found for this structure. The huprina X that is a hybrid of the tacrina with the huperzina A it showed HER likewise the most significant interactions as the more favorable energy values, what is in agreement with the high constant of inhibition of 26pM found in the literature for human's acetilcolinesterase. Before the obtained data we can end that the polyketides in spite of they obtain favorable energy values the formation of the compound polyketide-acetylcholinesterase these values are not competitive with the energy values found for the inhibitors tacrina and huprina X. however, in the production of a f?rmaco they are not taken into account just energy interactions and as the tacrina it already demonstrated to possess high hepatic toxicity, besides adverse reactions as nausea and vomit, the polyketides for they be natural substance were able to in this case be competitive if they demonstrated to possess softer adverse reactions.
O Mal de Alzheimer ? uma doen?a neurodegenerativa que atinge ?s fun??es cognitivas entre elas a mem?ria, aten??o e aprendizagem. A principal estrat?gia utilizada para seu tratamento est? direcionado na busca de melhorar a hipofun??o colin?rgica, inibindo a enzima acetilcolinesterase, para que a acetilcolina possa permanecer mais dispon?vel na fenda sin?ptica para as realiza??es das sinapses, j? que esta enzima tem a fun??o de hidrolisar a acetilcolina. A natureza oferece uma enorme variedade de subst?ncias utilizadas como f?rmacos e as esponjas marinhas tem demonstrado serem ricas nestas subst?ncias. Foram extra?dos da esponja Plakortis angulospiculatus tr?s policet?deos que atrav?s do m?todo Ellman demonstraram atividade anticolinester?sica. Atrav?s de t?cnicas de Modelagem Molecular, foram realizados c?lculos semiempiricos utilizando o m?todo PM3 para analisar as intera??es geom?tricas e energias envolvidas no complexo policet?deos-acetilcolinesterase com o objetivo de analisar uma poss?vel utiliza??o destes como f?rmacos para o Mal de Alzheimer. Como n?o se conhecia o estado em que o s?tio se encontraria (com a Ser200 e His440 neutros ou n?o) no momento da intera??o, foram realizados c?lculos para os tr?s policet?deos em ambos os s?tios. Estudos com inibidores j? conhecidos tacrina e huprina X (ambas neutra e protonadas) tamb?m foram realizados em ambos os s?tios a fim de compara??o. O resultados obtidos neste trabalho mostraram a confiabilidade do m?todo empregado, assim tamb?m como valores de entalpia favor?veis para a forma??o de todos os complexos policet?deo-acetilcolinesterase independente do s?tio. Observou-se pelos valores energ?ticos uma prefer?ncia quando os mesmos se encontravam no s?tio protonado diferencialmente dos inibidores tacrina e huprina X que independente do seu estado (protonados ou n?o) mostraram melhor intera??o pelo s?tio neutro. Os c?lculos realizados para a tacrina demonstraram que mesmo ap?s otimiza??o as principais intera??es j? descritas pela literatura se mantiveram e que possivelmente ela se encontra protonada dentro do s?tio visto os valores de energia encontrados para esta estrutura. A huprina X que ? um h?brido da tacrina com a huperzina A mostrou as intera??es mais significativas assim tamb?m como os valores energ?ticos mais favor?veis, o que est? de acordo com a alta constante de inibi??o de 26pM encontrados na literatura para a acetilcolinesterase de humano. Diante dos dados obtidos podemos concluir que os policet?deos apesar de obterem valores energ?ticos favor?veis a forma??o do complexo policet?deo-acetilcolinesterase estes valores n?o s?o competitivos com os valores energ?ticos encontrados para os inibidores tacrina e huprina X. No entanto, na fabrica??o de um f?rmaco n?o s?o levados em conta apenas intera??es energ?ticas e como a tacrina j? demonstrou possuir alta toxicidade hep?tica, al?m de rea??es adversas como n?usea e v?mito, os policet?deos por serem subst?ncia naturais poderiam neste caso ser competitivos se demonstrassem possuir rea??es adversas mais brandas.

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Swart, Chrisna. "Characterization of the interaction between acetylcholinesterase and laminin : a template for discovering redundancy." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20132.

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Thesis (PhD)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Apart from its primary function in the synaptic hydrolysis of acetylcholine, acetylcholinesterase (AChE) has been shown through in vitro demonstrations to be able to promote various non-cholinergic functions, including cell adhesion and neurite outgrowth, differentiation, and amyloidosis. AChE was also shown to bind to mouse laminin-111 in vitro by an electrostatic mechanism. Previous results suggest that the site on AChE recognised by certain monoclonal antibodies (MAbs) might be critical for differentiation. These MAbs were found to inhibit both laminin binding and cell adhesion in neuroblastoma cells. In this study, the structure and characteristics of this site were investigated, using the AChE-laminin interaction as a template as well as a detailed epitope analysis of the MAbs. The interaction sites of AChE and laminin were investigated using phage display, modelling and docking, synthetic peptides, enzyme linked immunosorbent assays (ELISAs) and conformational interaction site mapping. Docking of AChE with the single-chain variable fragments (scFvs) produced from the phage display showed the major recognition motifs to be the 90Arg-Glu-Leu-Ser-Glu-Asp motif, the 40Pro-Pro-Met-Gly sequence, and the 59Val-Val-Asp-Ala-Thr-Thr (human) motif. Mouse AChE was found to interact with the basic structures Val2718-Arg-Lys-Arg- Leu2722; Tyr2738-Tyr2739, Tyr2789-Ile-Lys-Arg-Lys2793; and Val2817-Glu-Arg-Lys2820, on the 1 G4 domain of laminin. ELISAs using synthetic peptides confirmed the involvement of the AG-73 site (2719-2729). This site overlaps with laminin’s heparin-binding site. Docking showed the major component of the interaction site on AChE to be the acidic Arg90-Glu-Leu-Ser-Glu-Asp95 (omega loop), and also involving the Pro40-Pro-Val42, Arg46 (linked to Glu94 by a salt bridge) and the hexapeptide Asp61 Ala-Thr-Thr-Phe-Gln66. Epitope analysis showed the MAb’s major recognition site to be the sequence Pro40-Pro- Met-Gly-Pro-Arg-Arg-Phe48 (human AChE). The MAbs also reacted with the prolinerich sequences Pro78-Gly-Phe-Glu-Gly-Thr-Glu84 and Pro88-Asn-Arg-Glu-Leu-Ser-Glu- Asp95. These results define the interaction sites involved in the AChE-laminin interaction and suggest that the interaction plays a role in cell adhesion. Despite the in vitro demonstrations of the importance of AChE’s non-classical functions, the AChE knockout survives. Results from this study suggest the possibility of functional redundancy between AChE and other molecules in early development. Using these in vitro findings that AChE is able to bind laminin-111, information on the interaction sites, as well as results from the monoclonal antibody (MAb) epitope analysis, the idea of redundancy was investigated. Docking and bioinformatics techniques were used to investigate structurally similar molecules that have comparable spatiotemporal expression patterns in the embryonic nervous system. AChE has been shown to be involved in the pathogenesis of Alzheimer’s disease, thus molecules associated with brain function and neurodegeneration were also investigated. Molecules with which AChE could be possibly redundant are syndecans, glypicans, perlecan, neuroligins and the low-density lipoprotein receptors and their variants. AChE was observed to dock with growth arrest-specific protein 6 (Gas6) as well as apolipoprotein E3 (ApoE-3) at the same site as the laminin interaction. The AChE interaction site was shown to resemble the apolipoprotein-binding site on the low density lipoprotein receptor, and related molecules, including the low density lipoprotein receptor-related molecule (LRP) and the sortilin-related receptor (SORL1). These molecules, along with apoE, are associated with Alzheimer’s disease. Resemblances to the triggering receptor on myeloid cells (TREM1) were also suggested; this is interesting as AChE has been implicated in both haematopoiesis and haematopoietic cancers. Coimmunoprecipitation results, applied to investigate alternative ligands for AChE, confirmed the AChE-laminin interaction in neuroblastoma cells, and also suggested the existence of other binding partners. In conclusion, characterisation of the AChE-laminin interaction sites and investigation of structurally similar sites in other molecules suggests a role for AChE in the stabilization of the basement membrane of developing neural cells and provides a feasible explanation for the survival of the knockout mouse. Furthermore, the demonstrated similarity of the AChE interaction site to sites on molecules, notably the low density lipoprotein receptor family and SORL1 and their apolipoprotein ligands that are implicated in the pathology of Alzheimer’s disease, as well as the possible link to haematopoietic differentiation and cancers, warrants further investigation.
AFRIKAANSE OPSOMMING: Talle in vitro studies wys dat die ensiem asetielcholienesterase (AChE), behalwe vir sy klassieke rol in die hidrolise van asetielcholien (ACh), ‘n aantal nie-cholinerge rolle vertolk insluitend in sel adhesie, in die uitgroei van neurieten, in differensiering, asook in amyloidosis. Dit is vooraf gewys dat AChE, met behulp van elektrostatiese meganismes, in vitro met muis laminin-111 kan bind. Dit word verneem dat die area op AChE wat herken word deur monoklonale teenliggaampies (MAbs), moontlik ‘n kritiese area is met betrekking tot differensiasie. Dieselfde MAbs is gevind om beide die laminin-interaksie, sowel as sel adhesie van neuroblastoma selle, te inhibeer. In hierdie projek word die struktuur en eienskappe van die betrokke kritiese areas ondersoek deur die AChE-laminin interaksie te gebruik as sjabloon. ‘n Gedetailleerde analise van die teenliggaam epitoop het ook geskied. Met behulp van faag vertoon, modellering en hegting, sintetiese peptiede, ensiem-gekoppelde immunosorbent toetse (ELISAs) en konformasie interaksie area kartering, is die betrokke interaksie areas bestudeer. Hegting van enkel-ketting varierende fragment (scFv) volgordes, verkry vanaf die vaag vertoon, aan AChE dui dat die hoof herkennings motiewe die 90Arg-Glu-Leu-Ser-Glu-Asp motief, die 40Pro-Pro- Met-Gly volgorde, en die 59Val-Val-Asp-Ala-Thr-Thr (mens) motief is. ‘n Interaksie tussen muis AChE en die 1 G4 domein van laminin is gevind. Die interaksie betrek die basiese structure: Val2718-Arg-Lys-Arg-Leu2722; Tyr2738-Tyr2739, Tyr2789-Ile-Lys-Arg- Lys2793; en Val2817-Glu-Arg-Lys2820. Die betrokkenheid van die AG-73 (2719-2729) area by hierdie interaksie is bevestig met ELISA eksperimente wat sintetiese peptiede inkorporeer. Die AG-73 area oorvleuel die heparin interaksie area op laminin. Hegtings eksperimente wys dat die hoof komponent van die interaksie area op AChE die suur volgorde Arg90-Glu-Leu-Ser-Glu-Asp95 op die omega-lus is. Die interaksie betrek ook die Pro40-Pro-Val42, Arg46 (gekoppel aan Glu94 deur ‘n sout-brug) en die heksapeptied Asp61 Ala-Thr-Thr-Phe-Gln66 motiewe. Analise van die MAb epitoop wys die hoof erkennings area as volgorde Pro40-Pro-Met-Gly-Pro-Arg-Arg-Phe48 (mens AChE). Die MAbs blyk ook gunstig te wees teenoor prolien-ryke volgordes soos Pro78-Gly-Phe-Glu-Gly-Thr-Glu84 en Pro88-Asn-Arg-Glu-Leu-Ser-Glu-Asp95. Die areas betrokke by die AChElaminin interaksie is dus gedefinieer en ‘n moontlike rol vir hierdie interaksie in sel adhesie word voorgestel. Die noodsaaklikheid van AChE se nie-klassieke funksies word bevraagteken na die oorlewing van die AChE uitklop-muis. Resultate hier dui op die moontlikheid van funksionele oortolligheid as verduideliking hiervan, spesifiek met betrekking tot molekules betrokke in vroëe ontwikkeling asook in die proses van neurale agteruitgang. Deur gebruik te maak van die in vitro demonstrasies van die AChE-laminin interaksie, informasie verkry ten opsigte van die betrokke interaksie areas, asook resultate verkry vanaf die monoklonale teenliggaam (MAb) epitoop analise, word die idee van funksionele oortolligheid ondersoek. Hegtings en bioinformatika tegnieke is gebruik om molekules met soortgelyke strukture en uitdrukkings patrone in die embrioniese senuweestelses te ondersoek. Ko-immuno presipitasie tegnieke is gebruik om so moontlike alternatiewe ligande vir AChE te ondersoek. Moontlike funksionele oortolligheid van AChE met die volgende molekules is gevind: syndecan; glypican; perlecan; neuroligin; asook die lae-digtheid lipoproteien (LDL) reseptore en hul variante. Hegting van AChE met ’growth arrest-specific’ proteien 6 (Gas6) en die apolipoproteien E3 (apoE3) is gedemonstreer en gevind om dieselfde area as die laminin interaksie te betrek. Die betrokke interaksie area op AChE het ooreenstemminge met die apolipoproteien interaksie area op die LDL reseptor asook met verwante molekules soos die lae-digtheids lipoproteien reseptor-geassosieerde molekuul (LRP) en die sortilingeassosieerde reseptor (SORL1). Hierdie molekules, insluitend apoE, speel beduidende rolle in die patologie van Alzheimer se siekte. Ooreenkomste tussen AChE en die verwekkings reseptor op myeloïde selle (TREM1) is ook voorgestel, die interaksie is van belang siende dat AChE voorheen geassosieer is met beide haematopoiesis en haematopoietiese kankers. Ko-immuno presipitasie resultate bevestig die AChE-laminin interaksie en dui op die moontlike teenwoordigheid van alternatiewe ligande vir AChE in vivo. In konklusie, karakterisering van die AChE-laminin interaksie areas, gepaard met identifisering van struktureel ooreenstemmende areas in ander molekules, dui op ‘n rol vir AChE in die stabilisering van die basale membraan en verskaf dus ‘n geldige verduideliking vir die oorlewing van die AChE uitklop-muis. Die ooreenstemming van die AChE interaksie area met areas op ander molekules (spesifiek geassosieer met Alzheimer se siekte), asook die moontlike assosiasie van AChE met haematopoietiese differensiering en kanker, lê die grondslag vir verdere ondersoeke.

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Cattaneo, Roberta. "Parâmetros metabólicos e histológicos de jundiás (Rhamdia quelen) expostos à formulação comercial do herbicida 2,4-diclorofenoxiacético (2,4-d)." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/11107.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
2,4-Diamin (2,4-D), or 2,4 dichlorophenoxyacetic acid is a systemic herbicide widely used in the world to control of broadleaf weeds. Agrochemicals of various classes are considered essential to agricultural development, but owing to toxic effects some of them can affect ecosystems through environmental contamination of soil and water. The presence of herbicides in aquatic system can contaminate fish and consequently, others animals, which feed on fish, causing indirectly contamination. Thus, the objective of this study was to investigate the effects of commercial formulation of herbicide 2,4-D concentrations of 400, 600 and 700 mg L−1, on metabolic parameters, acetylcholinesterase (AChE) activity and liver histological evaluation of silver catfish (Rhamdia quelen) exposed for 96 h. AChE activity increased in brain (600 and 700 mg L−1) and decreased in all concentrations tested in muscle tissue. Hepatic glycogen was reduced after 2,4-D exposure ranging from 47.7% (400 mg L−1) and 59.3% (700 mg L−1). Hepatic tissue showed lactate reduction at all 2,4-D concentrations tested and glucose was reduced only at 700 mg L−1. In the highest concentration tested hepatic glycogen, glucose reduced and plasma glucose levels increased. White muscle tissue showed glycogen reduction in fingerlings exposed to all herbicide concentrations and glucose reduction at 700 mg L−1. Muscle lactate levels increase at all 2,4-D concentrations tested. Vacuolation of hepatocytes and changes in their arrangement cords were observed by histologic al analysis in the group treated with 700 mg L−1 2,4-D. These results suggest that silver catfish exposed to 2,4-D concentrations near CL50 showed metabolic and histological responses to compensate some stress caused by herbicide exposure. Taken together parameters measured can be used as biomarkers to monitor fish contaminating by 2,4-D.
2,4-diamin (2,4-D), ou ácido 2,4 diclorofenoxiacético é um herbicida sistêmico amplamente utilizado no mundo para controle de plantas daninhas broadleaf. Agroquímicos de diversas classes são considerados essenciais para o desenvolvimento agrícola, mas podem afetar os ecossistemas através da contaminação ambiental do solo e da água, devido. A presença de herbicidas no sistema aquático pode contaminar os peixes e, consequentemente, outros animais, que se alimentam de peixes, causando indiretamente uma maior contaminação contaminação. Assim, o objetivo deste estudo foi investigar os efeitos da formulação comercial do herbicida 2,4-D nas concentrações de 400, 600 e 700 mg L-1 sobre parâmetros metabólicos, atividade da enzima acetilcolinesterase (AChE) e avaliação histológica do fígado de jundiás (Rhamdia quelen) expostos por um período de 96 h. Como resultados observamos que a atividade da AChE mostrou-se aumentada no cérebro (600 e 700 mg L-1) e diminuída no tecido muscular em todas as concentrações testadas. O glicogênio hepático foi reduzido, após exposição ao 2,4- D variando entre 47,7% (400 mg L-1) e 59,3% (700 mg L-1). Já no tecido hepático houve reduções do lactato em todas as concentrações testadas e da glicose apenas na concentração de 700 mg L-1 2,4-D. Na maior concentração testada o glicogênio hepático e a glicose apareceram reduzidos, ao contrário da glicose plasmática que estava com níveis aumentados. O glicogênio do tecido muscular mostrou-se reduzido nos alevinos expostos a todas as concentrações testadas do herbicida e na concentração de 700 mg L-1 houve redução da glicose. O lactato muscular aumentou em todas as concentrações de 2,4-D testadas. Foi observada vacuolização de hepatócitos e alterações no arranjo dos cordões hepáticos através da analise histológica no grupo tratado com 700 mg L-1 2,4-D. Estes resultados sugerem que os jundiás expostos a concentrações de 2,4-D perto da CL50 mostraram resposta metabólica e histológica compensatória ao estresse causado pelo herbicida. Assim, este conjunto de parâmetros medidos pode ser utilizado como biomarcador para acompanhar a possível contaminação dos peixes pelo herbicida 2,4-D.

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Kiem, Sara Alessia Verfasser], and Rainer [Akademischer Betreuer] [Rupprecht. "fMRT-Ruhenetzwerke gesunder Probanden : Prädiktion des HPA-Achsen-Status und Modulation durch Kortisolapplikation und -suppression / Sara Alessia Kiem. Betreuer: Rainer Rupprecht." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2013. http://d-nb.info/1036143856/34.

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Haselbeck, Christin [Verfasser]. "Fötale Programmierung: Der Einfluss von pränatalem Stress auf Entwicklung, Temperament und HHNR-Achsen-Funktion des Säuglings : eine prospektive Studie / Christin Haselbeck." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/103119052X/34.

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Höhn, David. "Der Zusammenhang zwischen Hirnmorphologie, Therapieantwort und HPA-Achsen-Aktivität bei der Depression : eine MRT-Untersuchung mittels voxelbasierter Morphometrie und automatisierter Regionalvolumetrie." kostenfrei, 2008. http://edoc.ub.uni-muenchen.de/8691/.

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Moraes, Bibiana Silveira. "Parâmetros toxicológicos em carpas (Cyprinus carpio) expostos a formulações comerciais de diferentes herbicidas em condições de lavoura de arroz e em laboratório." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/11092.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Pesticides can affect toxicological parameters and cause oxidative stress in fish. In Brazil there are few studies linking pesticide toxicity with fish. For this reason, two experiments were conducted to evaluate possible effects of herbicides on some toxicological parameters in carp (Cyprinus carpio). The fish were exposed to two commercial herbicides, one composed of a mixture formulated imazetapir and imazapic and the second composed of clomazone. The periods of exposure were seven days in the laboratory and seven, 30 or 90 days on rice field condition. After the experimental period, metabolic and toxicological parameters in the liver, brain and muscle tissues were evaluated. The enzymatic parameters analyzed in different tissues of this species were acetylcholinesterase activity (AChE), catalase (CAT) and glutathione S-transferase (GST). Also, oxidative stress parameters, such as carbonyl protein and TBARS levels in hepatic tissue, were analyzed. The metabolic parameters analyzed in liver and muscle of carp were glucose, glycogen, lactate, protein, amino acids and ammonia. Moreover, metabolic assessments were made (glucose, lactate and protein) in carp plasma. The results showed that AChE activity was increased in carp brain after seven days of exposure to a commercial formulation containing imazethapyr and imazapic herbicides both under field and laboratory conditions. In the same period of exposure, muscle tissue showed reduced activity of AChE after exposure to all herbicides (imazetapir and imazapic and clomazone) under laboratory conditions. At 30 days, in the field, AChE activity was reduced in brain and enhanced in muscle of carps exposed to imazethapyr and imazapic. Fish exposed to clomazone herbicide did not show any change in the activity of this enzyme in this period. On the other hand, at 90 days of exposure, only the fish exposed to the herbicide clomazone, showed a reduction in muscle AChE activity. The antioxidant enzyme catalase showed increased activity in liver tissue after seven days of exposure under both experimental conditions. At 30 days of exposure, catalase activity showed no further changes and after 90 days of exposure activity was reduced in liver of carp exposed to clomazone herbicide. The enzyme glutathione S-transferase was altered only after 30 and 90 days of exposure in the field. GST activity was reduced in liver tissue after exposure to both herbicides tested. TBARS levels were increased in almost all periods, terms of exposure and tissues considered, with the exception of brain tissue, which presented a decrease in TBARS levels at 30 days of exposure. Protein carbonyl was reduced in liver of carp exposed to clomazone herbicide after seven days under laboratory conditions. Moreover, at 30 and 90 days of exposure, the protein carbonyl levels were increased in the liver of fish exposed to both herbicides. After exposure to both herbicides, the carp showed metabolic disorders. In general, protein and amino acid levels were reduced and the amount of glycogen was enhanced in liver and muscle of carp exposed to both herbicides at all times tested. However, ammonia, lactate and glucose levels were increased and reduced according to the tissue considered, time of exposure and herbicide tested. These results indicate that the parameters measured may be good indicators of contamination of these commercial herbicides in Cyprinus carpio.
Os pesticidas podem afetar parâmetros toxicológicos e ainda causar estresse oxidativo em peixes. No Brasil existem poucos estudos relacionando toxicidade de pesticidas com peixes. Por esta razão foram conduzidos dois experimentos com objetivo de avaliar possíveis efeitos dos herbicidas sobre alguns parâmetros toxicológicos em carpas (Cyprinus carpio). Os peixes foram expostos a dois herbicidas comerciais, um composto pela mistura formulada de imazetapir e imazapic e o segundo composto por clomazone. Os períodos de exposição foram de sete dias em laboratório e por sete, 30 ou 90 dias em condição de lavoura de arroz. Após os períodos experimentais, nos tecidos hepático, cerebral e muscular foram avaliados parâmetros metabólicos e toxicológicos. Os parâmetros enzimáticos analisados foram a atividade da acetilcolinesterase (AChE), catalase (CAT) e glutationa S-transferase (GST) em diferentes tecidos desta espécie. Além disso, analisaram-se parâmetros de estresse oxidativo, como a carbonilação de proteínas e níveis de TBARS no tecido hepático. Os parâmetros metabólicos analisados foram glicose, glicogênio, lactato, proteína, amônia e aminoácidos em fígado e músculo de carpas. Ademais, foram feitas avaliações metabólicas (glicose, lactato e proteína) em plasma de carpas. Os resultados mostraram que a atividade da AChE foi aumentada em cérebro de carpas, após sete dias de exposição a formulação comercial contendo os herbicidas imazetapir e imazapic, em condições de campo e laboratório. Neste mesmo período de exposição, o tecido muscular mostrou redução da atividade da AChE após exposição as duas formulações comerciais em laboratório. Aos 30 dias em campo, a atividade da enzima AChE foi reduzida em cérebro e aumentada em músculo de carpas expostas a formulação contendo a mistura dos herbicidas imazetapir e imazapic. Os peixes expostos ao herbicida clomazone não mostraram alteração na atividade desta enzima, neste período. Já aos 90 dias de exposição, somente os peixes expostos ao herbicida clomazone, mostraram uma redução na atividade da AChE muscular. A enzima antioxidante catalase mostrou sua atividade aumentada no tecido hepático após sete dias de exposição em ambas as condições experimentais e às duas formulações comerciais testadas. Aos 30 dias de exposição, a enzima não foi alterada e após 90 dias de exposição a sua atividade foi reduzida em fígado de carpas expostas ao herbicida clomazone. A enzima glutationa S-transferase só foi alterada após 30 e 90 dias de exposição em campo. Sua atividade foi reduzida no tecido hepático após exposição às formulações comerciais dos herbicidas testados. Os níveis de TBARS foram aumentados em praticamente todos os períodos, condições de exposição e tecidos considerados, com exceção do tecido cerebral que aos 30 dias de exposição, mostrou os níveis de TBARS diminuídos. Os níveis de proteína carbonil foram diminuídos em fígado de carpas expostas por sete dias ao herbicida clomazone em laboratório. Por outro lado, aos 30 e 90 dias de exposição os níveis de proteína carbonil foram aumentados no fígado de peixes expostos as duas formulações comerciais. Após exposição aos dois herbicidas comerciais, as carpas demonstraram desordens metabólicas. De uma maneira geral, os níveis de proteína e aminoácidos foram diminuídos e o conteúdo de glicogênio aumentado em fígado e músculo de carpas expostas aos dois herbicidas comerciais e tempos testados. Porém, os níveis de amônia, lactato e glicose mostraram alterações variáveis de acordo com o tecido considerado, com o tempo de exposição e com o herbicida testado. Estes resultados indicam que os parâmetros medidos podem ser bons indicadores da contaminação destes herbicidas comerciais em Cyprinus carpio.

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42

Roth, Morgan Alicia. "Methods for controlling two European Honey bee (Apis mellifera L.) pests: Varroa mites (Varroa destructor, Anderson and Trueman) And Small hive beetles (Aethina tumida)." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/100994.

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Throughout the last five decades, European Honey bee (Apis mellifera) colonies have been heavily damaged by invading Varroa mites (Varroa destructor), and, more recently, small hive beetles (Aethina tumida). These pests infest A. mellifera colonies throughout Virginia, with V. destructor feeding upon the lipids of their hosts and spreading viruses, and A. tumida feeding extensively on hive products and brood. Because V. destructor has historically demonstrated acaricide resistance, this study examined V. destructor resistance to three common acaricides (amitraz, coumaphos, and tau-fluvalinate) throughout the three geographic regions of Virginia using glass vial contact bioassays; the results showed no resistance in the sites tested. To gain better insights into A. tumida pharmacology, several known acetylcholinesterase (AChE) inhibitors and three novel insecticides (previously shown to have low mammalian toxicity) were tested against an A. tumida laboratory colony through in vivo and in vitro bioassays. The results of these bioassays indicated that coumaphos was most selective and topically effective against A. tumida, while only one experimental compound was selective against A. tumida, with 29-fold less potency than coumaphos. These results can help apiculturists in making informed pest management choices and can lead to future studies further examining V. destructor resistance and optimizing A. tumida insecticide treatments.
Master of Science in Life Sciences

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43

Leung, Ka Wing. "PRiMA, a membrane anchor of tetrameric acetylcholinesterase (AChE), directs the restricted localization of the enzyme in muscle and neuron /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202009%20LEUNG.

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44

Pretto, Alexandra. "Parâmetros toxicológicos em jundiás (Rhamdia quelen) expostos ao cádmio." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/11094.

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The aquatic ecosystems may be constantly receiving metals from industrial discharges and agriculture generated by anthropogenic activities. Thus, the organisms in the aquatic environment may be the target of these contaminants. The aim of this study was verify cadmium effects on silver catfish (Rhamdia quelen) metabolism. First was verified the lethal concentration (LC50) 96 hours of cadmium for silver catfish and was obtained the value of 1.7 mg/L. Then juvenile of R. quelen were exposed for seven and 14 days to 10% and 20% of LC50. At the end of exposure periods the fish were subjected to recovery periods of seven and 14 days. The parameters analyzed were the activity of the enzyme acetylcholinesterase (AChE) (brain and muscle), oxidative stress through parameters such as protein carbonyl (liver), TBARS (brain, liver, kidney, gills) and the antioxidant enzymes catalase, glutathione S-transferase and superoxide dismutase (liver, kidney and gills). Furthermore, general parameters related to metabolism as glycogen, glucose, lactate, protein, amino acids and ammonia (liver, muscle and plasma) and metal accumulation were verified. The activity of brain AChE was not changed after seven days of exposure but significant inhibition was observed after 14 days of exposure and recovery. After the exposure periods, the muscle AChE was increased (seven days) and inhibited (14 days). Increase in protein carbonyl occurred after seven days of exposure and reduction was found after seven days of recovery. The same exposure period caused an increase in TBARS in the brain and gills and reduction in kidney. Following the recovery for seven days, an increase of TBARS occurred in the liver and reduction in the gills. After the exposure for 14 days TBARS increase was observed in all tissues tested. In the kidney values return to the control levels after the recovery of 14 days. The activity of liver catalase increased and reduced in gills after the exposure periods and the recovery for seven days caused reduction of the enzyme in the two tissues. In the kidney no change was observed in the activity of this enzyme. The activity of liver glutathione S-transferase increased after exposure for seven days and reduced after the same recovery period. In the gills a significant decrease occurred after exposure (seven and 14 days) and activity only returned to the control values after 14 days of recovery. The liver superoxide dismutase activity reduced after exposure periods and was recovered only after 14 days. The metabolic parameters presented changes according to tissue and time of exposure. In the liver occurred increase of lactate, protein and amino acids and reduction of glucose after exposure to cadmium for seven days. In the recovery period of seven days, the glycogen levels increased and the other parameters returned to the control values. Following 14 days of exposure the liver protein concentration reduced however, the amino acids and ammonia levels increased. After the recovery of 14 days, amino acids and ammonia remained increased, lactate also increased and reduced glycogen in this period. In the muscular tissue protein reduction and increase of amino acids, ammonia, glycogen and glucose were observed after exposure (seven days). In seven days of recovery, glucose remained increased and protein reduced. After 14 days of exposure also was observed reduction of protein, but there was an increase of glucose. In the recovery of 14 days only the ammonia levels had increased. In plasma, glucose, lactate and protein were altered after exposure to cadmium. Lactate increased after seven days and silver catfish showed glucose, lactate and protein reduced after 14 days. Lactate reduced after seven days in recovery and the protein levels remained low after the recovery for 14 days. In general the cadmium accumulation was higher in kidney, liver and gills as compared to the brain and muscle. Thus, the changes observed indicate that cadmium affects the silver catfish metabolism. The parameters analyzed can be good indicators of cadmium toxicity.
Os ecossistemas aquáticos podem estar recebendo constantemente metais provenientes de descargas industriais e da agricultura geradas por atividades humanas. Desta forma, os organismos presentes no meio aquático podem ser alvo destes contaminantes. O objetivo deste estudo foi verificar os efeitos do cádmio sobre o metabolismo de jundiás (Rhamdia quelen). Neste trabalho primeiramente verificou-se a concentração letal média (CL50) do cádmio para o jundiá, obtendo-se o valor de 1,7 mg/L. Em seguida juvenis de R. quelen foram expostos por sete e 14 dias à 10% e 20% do valor da CL50. Ao final da exposição, os peixes foram submetidos a períodos de recuperação de sete e 14 dias. Os parâmetros analisados foram a atividade da enzima acetilcolinesterase (AChE) (cérebro e músculo), ocorrência de estresse oxidativo através de parâmetros como proteína carbonil (fígado), formação de espécies reativas ao ácido tiobarbitúrico (TBARS) (cérebro, fígado, rim, brânquias) e as enzimas antioxidantes catalase, glutationa S-transferase e superóxido dismutase (fígado, rim e brânquias). Além disso, parâmetros gerais relacionados ao metabolismo como glicogênio, glicose, lactato, proteína, aminoácidos e amônia (fígado, músculo e plasma) e acumulação de metais (cérebro, músculo, fígado, rim e brânquias) foram determinados. A atividade da AChE cerebral não foi alterada após sete dias de exposição mas foi observada significante inibição após 14 dias de exposição e recuperação. Após os períodos de exposição, a AChE muscular foi aumentada (sete dias) e reduzida (14 dias). Ocorreu aumento de proteína carbonil após sete dias de exposição e redução após sete dias de recuperação. O mesmo período de exposição provocou aumento de TBARS no cérebro e brânquias e redução no rim. Seguindo a recuperação por sete dias ocorreu aumento de TBARS no fígado e redução nas brânquias. Após a exposição de 14 dias foi observado aumento de TBARS em todos os tecidos analisados, e somente no rim os valores retornam aos níveis do controle após a recuperação de 14 dias. A atividade da catalase aumentou no fígado e reduziu nas brânquias após os períodos de exposição. Na recuperação (sete dias) ocorreu redução da atividade da enzima nos dois tecidos. No rim nenhuma alteração foi observada na atividade desta enzima. A atividade da glutationa S-transferase aumentou no fígado após a exposição por sete dias e reduziu após o mesmo período de recuperação. Nas brânquias ocorreu um decréscimo significante após exposição (sete e 14 dias) e a atividade só retornou aos valores do controle depois de 14 dias de recuperação. A atividade da superóxido dismutase, analisada no fígado, reduziu após os períodos de exposição e foi recuperada somente após 14 dias em água sem adição de cádmio. Os parâmetros relacionados ao metabolismo apresentaram alterações de acordo com o tecido considerado e tempo de exposição. No fígado ocorreu aumento de lactato, proteína e aminoácidos e redução de glicose na exposição ao cádmio por sete dias. Na recuperação por sete dias, os níveis de glicogênio aumentaram e os demais parâmetros retornaram aos valores do controle. Seguindo 14 dias de exposição, a concentração de proteína hepática reduziu enquanto os níveis de aminoácidos e amônia aumentaram. Após a recuperação de 14 dias, aminoácidos e amônia permaneceram aumentados, lactato também aumentou e glicogênio reduziu neste período. No tecido muscular ocorreu redução de proteína e aumento de aminoácidos, amônia, glicogênio e glicose após exposição (sete dias). Na recuperação por sete dias, glicose permaneceu aumentada e proteína reduzida. Após 14 dias de exposição também foi verificada redução de proteína, mas ocorreu aumento de glicose e neste período de recuperação somente os níveis de amônia apresentaram aumento. No plasma, glicose, lactato e proteína foram alterados após exposição ao cádmio. Lactato aumentou após sete dias e depois de 14 dias expostos, jundiás demonstraram redução de glicose, lactato e proteína. Lactato reduziu após sete dias em recuperação e os níveis de proteína continuaram reduzidos após a recuperação por 14 dias. De maneira geral a acumulação de cádmio foi maior no rim, fígado e brânquias em comparação com o cérebro e músculo. Desta forma, as alterações observadas indicam que o cádmio afeta o metabolismo de jundiás. Os parâmetros analisados podem ser bons indicadores de toxicidade para cádmio.

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45

Acken, David van [Verfasser]. "Melt-Rock interaction and refertilization of oceanic lithosphere – a highly siderophile element and Os isotope study, Totalp Massif, Switzerland / David van Acken." Berlin : Freie Universität Berlin, 2009. http://d-nb.info/1023464489/34.

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46

Flemmer, John [Verfasser], Reinhart [Akademischer Betreuer] Poprawe, and Gerd [Akademischer Betreuer] Witt. "CAM-NC-Datenkette für die Laserbearbeitung von Freiformflächen mit simultaner Bewegung mechanischer Achsen und galvanometrischem Laserscanner / John Flemmer ; Reinhart Poprawe, Gerd Witt." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1176422057/34.

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47

Ache, Fabian [Verfasser], and Mandy [Akademischer Betreuer] Hütter. "Returning advice taking to the wild : Empirical, theoretical, and normative implications of an ecological perspective / Fabian Ache ; Betreuer: Mandy Hütter." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1196616884/34.

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48

Cho, Sook-Hee. "The Double and Narcissism in Harold Pinter's Plays: A Study of A Slight Ache, The Caretaker, and No Man's Land." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1391785610.

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Cavassana, Sidnei [UNESP]. "Estudo sobre agulhas hipodérmicas: variação do esforço de penetração em um tecido artificial." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151641.

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O medo da dor relacionada à injeção é um empecilho à terapia de injetáveis. As injeções hipodérmicas são motivos de grande ansiedade e de reduzida adesão à aplicação subcutânea de insulina para o controle glicêmico em diabéticos ou no tratamento da esclerose múltipla, aumentando o risco de complicações e mortalidade. Neste trabalho foi analisado como algumas das características da agulha podem influenciar a sensação de dor na injeção. Mediu-se o esforço de penetração de agulhas em um tecido artificial (modelo substituto da pele), para diferentes diâmetros de cânula, rugosidade, profundidade de penetração, lubrificação e ângulos do bisel da ponta perfurante. Este estudo visou encontrar alternativas para facilitar a aplicação e a autoaplicação de injeções hipodérmicas, aumentando a segurança e conforto, diminuindo a intensidade da dor percebida pelo paciente. Para isso, analisou-se no projetor de perfil e no MEV o bisel de agulhas usadas repetidas vezes para verificar a perda do perfil ou a formação de rebarbas que possam dificultar a penetração ou traumatizar o tecido durante o reuso de agulhas. Também foi analisado sob o ponto de vista mecânico, o que pode ser feito para prevenir que as agulhas usadas na aplicação subcutânea não atinjam inadvertidamente o músculo. O maior esforço de penetração observado nas agulhas com maior ângulo do bisel é responsável pela percepção de dor do paciente.
Fear of injection-related pain is a drawback to injectable therapy. Hypodermic injections are a cause for great anxiety and reduced adherence to the subcutaneous application of insulin for glycemic control in diabetics or in the treatment of multiple sclerosis, increasing the risk of complications and mortality. In this work, it was analyzed how some of the characteristics of the needle can influence the sensation of pain in the injection. The needle penetration effort was measured in an artificial tissue (substitute skin model) for different cannula diameters, roughness, depth of penetration, lubrication and angles of the perforating tip bevel. This study aimed to find alternatives to facilitate the application and self-application of hypodermic injections, increasing safety and comfort, reducing the pain intensity perceived by the patient. To do this, the bevel of needles used repeatedly was analyzed in the profile projector and SEM to verify the loss of the profile or the formation of burrs that could hamper the penetration or traumatize the tissue during the reuse of needles. It has also been mechanically analyzed, which can be done to prevent that the needles used in the subcutaneous application do not inadvertently reach the muscle. The greater penetration effort observed in the needles with greater angle of the bevel is responsible for the patient's perception of pain.

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Brell, Claus. "Lernmedien und Lernerfolg - reale und virtuelle Materialien im Physikunterricht empirische Untersuchungen in achten Klassen an Gymnasien (Laborstudie) zum Computereinsatz mit Simulation und IBE." Berlin Logos-Verl, 2007. http://d-nb.info/987938401/04.

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Dissertations / Theses on the topic 'Achen'

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