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1

GRENI, FEDERICO. "Variabilità fenotipica nell'emocromatosi: studio di due potenziali modificatori genetici in PCSK7 e GNPAT." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2017. http://hdl.handle.net/10281/140994.

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Introduction and aim: Hereditary hemochromatosis (HH) is a genetic disease characterized by a progressive iron overload in different tissues. Homozygosity for the p.C282Y mutation is the most frequent genotype associated with the disease and it is directly responsible for an inappropriate production of hepcidin, the main regulator of iron homeostasis. Several evidences indicated that p.C282Y homozygous genotype has an incomplete penetrance due to the combined action of genetic and acquired modifier factors. Recently, the attention was focused on GNPAT rs11558492 and PCSK7 rs236918 single nucleotide polymorphisms (SNPs). The aim of my thesis was to analyse the role of these potential genetic modifiers in an Italian cohort of p.C282Y homozygotes. Materials and methods: Patients: 298 patients (205 males and 93 females) and 169 healthy controls. Exclusion criteria were: alcohol intake >50 g/day in men and >30 g/day in women, chronic hepatitis, inflammatory status. SNPs genotyping was performed by ARMS-PCR or PCR-RFLP. Random samples were confirmed by direct sequencing. Patients and controls allelic and genotypic frequencies were compared to EVS database and analysed according to serum ferritin levels (SF), liver iron concentration (LIC) measured by liver biopsy or magnetic resonance, iron removed (IR) and liver fibrosis histologically assessed by Ishak score (IS). Fisher’s exact test, chi-squared test and t-test were used to perform statistical comparisons between groups and averages of considered variables. Results: GNPAT rs11558492 analysis. Our results demonstrated that: a. allelic and genotypic frequencies were comparable among patients, controls and EVS data. No significant differences were found even considering two subgroups of males only with extreme phenotypes (SF <1000 mcg/L, IR <5 g and/or LIC <100 mcmol/g vs SF >2000 mcg/L, IR >10 g and/or LIC> 50 mcmol/g); b. according to iron indices, allelic and genotypic frequencies did not significantly differ neither among patients nor compared to controls, limited to SF; c. similarly, minor allele (G) frequency did not differ between patients with absent/mild fibrosis and patients with severe fibrosis/cirrhosis (20.5% vs 25%). PCSK7 rs236918 analysis. Our study demonstrated that: a. minor allele (C) frequency was higher in patients with severe fibrosis/cirrhosis than in patients with absent/mild fibrosis (21.9% vs 7.1%; p=0.003); b. C-allele carriers were more likely to have worse liver staging scores than wild-type patients (OR=2.77, p=0.0018; ORmale-only=2.56, p=0.0233); c. PCSK7 genotype has a direct effect on severe fibrosis/cirrhosis (OR=3.11, p=0.0157) and a mild nonsignificant indirect effect mediated through SF and IR (mediation analysis: 22% and 28%, respectively). Conclusions: Our results demonstrated that: a. GNPAT rs11558492 is not a major modifier of iron status in HH patients and controls, and is not associated with severe fibrosis/cirrhosis in HH patients. b. PCSK7 rs236918 C allele is a risk factor for cirrhosis development in Italian HH patients.
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2

Correia, Bárbara Catarina Gonçalves. "Determinig how membrane phospholipids regulate CNS myelination and myelin composition." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22236.

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Mestrado em Biologia Molecular e Celular
Rhizomelic chondrodysplasia punctata (RCDP) is an autosomal recessive disorder characterized by a defect in peroxisomal enzymes responsible for the biosynthesis of plasmalogens. This leads to a deficiency of this type of glycerophospholipid, and patients present bone abnormalities, and mental retardation. This disorder can be caused by mutations in the GNPAT gene, which encodes the first enzyme necessary for plasmalogen synthesis. Some studies have shown that myelination in the peripheral and central nervous system is affected by the loss of plasmalogens. However, it is unknown how this defect in myelination is orchestrated in a cellular and molecular scenario. With this work, we showed that it is possible to use in vitro co-cultures of cortical neurons and oligodendrocytes, from WT and Gnpat KO mice, to investigate the relation between both cells and what leads to demyelination. This strategy can also help to test different candidates for therapies. Alkyl-glycerols have been indicated as an alternative precursor of plasmalogens, but until now their efficiency to restore plasmalogen levels is still not proven in nervous tissue. We used one type of alkyl-glycerol named 1-O-tetradecyl-glycerol, and it was able to restore the defective myelination in Gnpat KO co-cultures. Myelin is also rich in proteins, and some have important functions for compaction and maintenance of the myelin sheaths. Therefore, it is important to analyze how the proteins are affected by the lack of plasmalogens. We used Western blot to analyze different proteins present in compact and non-compact myelin. We observed a significant decrease in the amount of myelin basic proteins (MBP) in myelin isolated from brain and spinal cord of Gnpat KO mice. MBP is essential to keep the myelin sheaths compact and functional. Other proteins like tubulin polymerization-promoting protein (TPPP) showed no differences in brain or in spinal cord myelin, since this protein is known to regulate the differentiation of oligodendrocytes, and our previous results did not evidence any problems during differentiation.
Condrodisplasia rizomélica puncata é uma doença autossómica recessiva caracterizada por um defeito em enzimas peroxisomais responsáveis pela biossíntese de plasmalogénios. Estes defeitos causam uma deficiência na produção deste fosfolípido e os doentes apresentam anormalidades ósseas e um atraso mental. Esta doença pode ser causada por mutações no gene que codifica a enzima GNPAT que é a primeira enzima necessária para a síntese de plasmalogénios. Alguns estudos demonstraram que a mielinização é afetada pela perda de plasmlalogéneos no sistema nervoso central e periférico. Contudo, ainda não se sabe como é que este defeito se processa a nível celular e molecular. Com o presente trabalho, demonstramos que é possível usar co-culturas in vitro de neurónios corticais e de oligodendrócitos, provenientes de ratinhos wildtype (WT) e knockout (KO), possibilitando a investigação da relação entre os dois tipos de células e o que origina a desmielinização observada in vivo. Este método in vitro também pode ser usado para testar diferentes candidatos para eventuais terapias. Os alquil-glicerois já foram indicados como um percursor alternativo de plasmalogénios, mas a sua eficácia nunca foi comprovada em tecidos neuronais. Neste trabalho usámos um tipo de alquil-glicerol, denominado 1-O-tetradecil-glicerol, capaz de restaurar os defeitos da mielina nas co-culturas de ratinhos Gnpat KO. A mielina é também rica em proteínas e algumas têm funções importantes na compactação e manutenção da mielina. Por esse motivo, é importante estudar como é que as proteínas da mielina são afetadas pela deficiência em plasmlalogéneos. O western blot foi usado para analisar as diferentes proteínas presentes tanto na mielina compacta como na mielina não compacta. Os resultados demonstraram um decréscimo significativo da proteína básica de mielina (MBP) em mielina isolada do cérebro e espinal medula de ratinhos KO. Esta proteína é essencial para manter os segmentos de mielina compactos e funcionais. A proteína promotora de polimerização de tubulina (TPPP) não demonstrou diferenças, quer em mielina do cérebro quer da espinal medula. Esta proteína é responsável por regular a diferenciação dos oligodendrócitos e os nossos resultados mostram que um defeito em plasmalogénios não afeta a diferenciação dos oligodendrócitos, mas especificamente a produção de mielina por estas células.
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3

Bealmear, Stacey. "Fungus Gnat Integrated Pest Management." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2010. http://hdl.handle.net/10150/144781.

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4

Biktchourina, Angelina. "Les verbes gnat' / gonjat' : sémantique, catégorie grammaticale, dérivation et phraséologie." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE3030/document.

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Dans cette thèse, nous avons étudié d’une manière structurée et détaillée la sémantique des verbes gnat’ et gonjat’. Pour cela, nous avons tout d’abord formalisé leur potentiel sémantique qui comprend les composants de leur valeur de base et ce qu’ils génèrent dans des situations nouvelles, dans des cotextes particuliers. Pour chaque valeur sémantique, nous avons présenté un schéma sémantique, un schéma actantiel en précisant les rôles sémantiques, la nature des actants et leur réalisation syntaxique, ainsi que des illustrations d’emploi dans des cotextes des plus représentatifs, des synonymes, la famille morphologique. Les valeurs plus ou moins communes à gnat’ et à gonjat’ ont été étudiées ensemble, ce qui nous a permis de mettre en évidence leurs similitudes et différences. Puis, nous avons traité la question de la catégorie grammaticale des verbes de mouvement. Après avoir exposé les propriétés traditionnellement attribuées aux corrélats déterminé / indéterminé et les particularités qui sont générées dans l’emploi de chacun de ces corrélats, nous avons analysé la corrélation déterminé / indéterminé en général, et en particulier, entre gnat’ et gonjat’. Faisant partie de la catégorie grammaticale des verbes de mouvement, gnat’ et gonjat’ s’opposent sur le plan grammatical en tant que déterminé vs indéterminé et leurs caractéristiques grammaticales induisent quelques différences sémantiques. Ainsi, la plupart des différences observées entre gnat’ et gonjat’ ne sont pas en fait pas d’ordre lexical, mais résultent des différences grammaticales du déterminé gnat’ et de l’indéterminé gonjat’. Dans la partie consacrée à la dérivation morphologique, nous avons eu pour objectif d’examiner les effets de la préverbation et les modifications de sens que la préverbation entraîne pour ces verbes. Nous avons étudié les préverbés formés sur la base de gnat’ / gonjat’ à valeur spatiale en les regroupant en fonction de l’orientation spatiale : à partir du point de départ, vers le point d’arrivée, les deux en même temps ou en rapport avec un repère. Une attention minutieuse a été accordée aux différences sémantiques et aspectuelles de certains préverbés partageant les mêmes valeurs spatiales. L’étude des préverbés combinés aux préverbes à valeur non spatiale a été organisée en fonction de la morphologie de l’aspect : les préverbés hors couple et les couples de verbes. Quelques particularités ont été observées. Pour que l’étude sémantique soit complète, nous y avons inclus la question des phrasèmes comportant ces verbes. Puis, nous avons analysé le parallélisme qui existe entre gnat’ / gonjat’ simples et préverbés et le verbe dit de position sidet’ : les valeurs que ces verbes ont en commun et aussi, les limites de leur corrélation, Enfin, en partant directement des situations linguistiques concrètes avec gnat’ / gonjat’ simples et préverbés nous avons exposé un certain nombre de mécanismes qui aboutissent à un effet expressif
In this thesis, we have studied the semantics of the verbs gnat’ and gonjat’ in a structured and extensive way. To achieve this, we began by structuring their semantic potential, which includes their basic value and what it produces in new situations, in specific cotexts. For each semantic value, we have presented a semantic schema, mapping the semantic roles of the actants, their nature and their syntactic development, together with examples of usage in the most representative cotexts, the synonyms, the morphological family. The more or less common values of gnat’ and gonjat’ have been studied together, so that we could bring their similarities and differences to light. Then, we dealt with the question of the grammatical category of the verbs of motion. Having presented the usually attributed properties of the correlate determined / indetermined and the particularities that emerge in the usage of each of these correlates, we have focused on the determined / indetermined correlation in general and between gnat’ and gonjat’ in particular. While belonging to the same grammatical category of the verbs of motion, both gnat’ and gonjat’ are opposed on a grammatical level, as determined and indetermined, and their grammatical characteristics lead to some semantical differences. Hence, most of the observed differences between gnat’ and gonjat’ are not of a lexical type; they are rather the result of the semantical differences between the determined gnat’ and the indetermined gonjat’. In the part of our thesis dedicated to morphological derivation, our goal was to study the impacts of verbal prefixation and the change of meaning as a result of the prefixation for these verbs. We have studied prefixed verbs based on gnat’ / gonjat’ with spatial meanings, clustering them depending on their spatial orientation: from the starting point, to the point of arrival, both at the same time or in relation to a landmark. A particular focus has been placed on the semantical and aspectual differences of some verbs with prefixes that share the same spatial values. The analysis of verbs with spatial prefixes was done according to the morphology of the aspect: the verbs with prefixes outside aspectual pairs and the pair of verbs. Some particularities have been observed. For the semantic study to be complete, we have added the question of the phrasemes using these verbs. Then, we studied the similarity between gnat’ and gonjat’ in their simple and prefixed forms and the verb of position sidet’: what those verbs have in common but also the limits of their similarities. Finally, we have taken concrete linguistic situations involving gnat’ and gonjat’ in their simple and prefixed forms in order to outline a number of mechanisms leading to an expressive result
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5

Mallinson, Helen. "The gnat and the vacuum : Robert Boyle and the history of air." Thesis, Birkbeck (University of London), 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.581441.

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The thesis presents an intellectual history of air. It investigates a critical period when the concept of air changed from being an all pervasive 'element' within a predominantly Aristotelian cosmology, to an 'ocean', or a fluid and particulate body with mass and weight. The thesis is set in the context of the seventeenth-century revolution in science in England and is focused on the pneumatic work of Robert Boyle. The question behind the thesis is raised by a specific experiment published by Boyle in 1672 when he describes how he tried, and failed, to produce gnats in a flask that had been evacuated of air by his air-pump. The historical aspect of the thesis examines the development of the vacuum, a new and revolutionary experimental site, in tandem with the equally revolutionary developments in physiology. The philosophical aspect of the thesis examines the conceptual ideas being played out in the Gnat Experiment and the relation between natural philosophy and theology. In terms of its empirical method the experiment was emblematic of the new science being developed by Boyle. The ambition behind the experiment, however, and Boyle's disappointment at its failure, engages another level of enquiry. Of particular interest is the problem of 'thinking matter' and the conflicts it provoked in relation to discussions of air and the vacuum, life and soul. Though reignited by Descartes, the discussion can be traced back to the early theories of air in Presocratic philosophy and the development of the 'pneumatic tradition' through later Socratic and Stoic philosophy, as well as Christian theology, in the guise of pneuma. It becomes apparent that Boyle's 'air' engages a complex field of concepts and arguments that can be traced back to the beginnings of philosophy and science, and that are still burning.
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Nigh, Edward L. Jr, Christopher Sumner, and Thomas Svodoba. "An Evaluation of Biological Agents for Control of Citrus Nematode and Liohippelates Eye Gnat." College of Agriculture, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/220522.

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Biological agents have been employed in a series of experiments to evaluate their efftcacy,in control of the citrus nematode and Liohippelates eye gnat in the Yuma mesa area. Steinernema riobravis, an entomopathological nematode, considered climatically adapted to western Arizona temperatures, was selected from commercially available sources. Three field trials and a greenhouse study utilizing the nematodes at population ratés of one and two billion juveniles per acre were each unsuccessful in reducing the nematode or insect pest. Poor viability and survival were attributed to the negative results in each of the investigations. The microbial nematicide, DiTera, which was included in two limited trials, was found to be highly effective in suppression of citrus nematode populations infecting Yuma citrus. These results have prompted Abbott Laboratories, manufactures of the product; to establish two demonstration plots in the Yuma mesa area.
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MONROY, MEJIA MANUEL RODRIGO. "Control de Fungus gnat durante el enraizamiento ex vitro de esquejes de planta de papa." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/99441.

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Con el objetivo de controlar Fungus gnat (Bradysia difformis) durante el enraizamiento ex vitro de esquejes de plantas de papa (Solanum tuberosum L.) dentro del área de enraizamiento de la empresa Agrícola Villarreal S.P.R. de R.L., dedicada a la producción de semilla de papa, se realizó el estudio en el siguiente orden, primero se inició con la colecta e identificación de ejemplares del insecto plaga, la cual fue identificada como: Bradysia difformis. En seguida se hicieron diferentes pruebas a diferentes concentraciones de enraizadores (Hormovit® y Raizal 400®) y sustratos como control cultural, obteniéndose la mejor calidad de planta con el tratamiento de fibra de coco y 0.1 g.L-1 de Raizal 400®. Después de obtener plantas de calidad se hicieron pruebas con dos productos amigables con el ambiente: VectoBac® (Bacillus Thurigensis var. Israelensis) y Azanim® (Azadiractina 3% CE) a diferentes dosis (0.5, 1.0, 2.5 y g.L-1 o mL.L-1, según el caso) y testigo. El control químico se realizó con una mezcla de tres productos: HERALD ® (Fenpropatrin), AMBUSH 34® (Permetrina) más TIRANO 200 CE® (Cipermetrina) a una dosis de 0.5 mL.L-1 de cada uno y, se comparó con VectoBac® a una dosis de 2.5 g.L-1, que resultó ser el insecticida y la concentración más eficiente en el control de Fungus gnat. Las aplicaciones de dichos productos se realizaron bajo invernadero plagado. Se realizaron cuatro aplicaciones, una por semana en aspersión al igual que los conteos de plantas (% de mortandad y/o sobrevivencia). Una vez realizadas las pruebas con los insecticidas se aplicó el mejor producto en el área de enraizamiento de la empresa y finalmente se colocaron trampas para evaluar el índice de población y el conteo de hembras y machos en el área de enraizamiento de Agricola Villarreal S.P.R. de R.L., en todas las semanas se obtuvo una relación de 2:1 machos:hembras (66:33 XIII machos:hembras). Finalmente se erradicó Bradysia difformis en el lugar, con una quinta aplicación.
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Anas, Osama. "Interactions between Sclerotinia sclerotiorum (Lib.) de Bary, Bradysia coprophila Lintner (dark-winged fungus gnat) and mycoparasitic fungi." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75777.

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Sclerotinia sclerotiorum is a pathogen of crops grown in the muck soil regions of Quebec. Soil baiting tests indicated that the sclerotia of S. sclerotiorum are attacked and destroyed by the larvae of Bradysia coprophila and mycoparasites. Sclerotia with rinds partially damaged by the larvae were found to be more susceptible to mycoparasitism by Trichoderma viride. Increasing the organic matter content and porosity of soils resulted in increased damage to sclerotia when larvae were present. Studies conducted to determine if larvae could be reared on diets of various fungi and plant tissue showed that mycelia and sclerotia of S. sclerotiorum were the most successful food sources, followed by mycelia and sclerotia of Botrytis porri and Rhizoctonia solani. Adults produced on mycelia and sclerotia of Sclerotinia minor, Fusarium solani f. sp. pisi, and Botrytis cinerea seldom were fertile. Larvae generally failed to survive when reared on cultures of Trichoderma viride. Larval development occurred on all plants inoculated with the above pathogens but failed to occur on noninoculated healthy plants. Salivary gland secretions of the larvae were found to inhibit the germination of sclerotia. Analyses of the secretion determined that it contains 4.3% protein and had chitinase activity. Mechanically damaged and undamaged sclerotia exhibited an increase in eruptive mycelial germination when treated with 1.5 $ mu$g ml$ sp{-1}$ chitinase but germination decreased at 50, 100 and 150 $ mu$g ml$ sp{-1}$ chitinase concentrations. Noneruptive mycelial germination and carpogenic germination occurred when sclerotia were treated with acetate buffer and distilled water.
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Mochizuki, Ko. "Diversity of plants pollinated by fungus gnats and associated floral syndrome." Kyoto University, 2018. http://hdl.handle.net/2433/232293.

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Vaughan, Martha Marie. "Molecular and Functional Characterization of Terpene Chemical Defense in Arabidopsis Roots in Interaction with the Herbivore Bradysia spp. (fungus gnat)." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77974.

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Roots and leaves are integrated structural elements that together sustain plant growth and development. Insect herbivores pose a constant threat to both above- and belowground plant tissues. To ward off herbivorous insects, plants have developed different strategies such as direct and indirect chemical defense mechanisms. Research has primarily focused on visible aboveground interactions between plants and herbivores. Root-feeding insects, although often overlooked, play a major role in inducing physical and physiological changes in plants. However, little is known about how plants deploy chemical defense against root herbivores. We have developed an Arabidopsis aeroponic culture system based on clay granulate, which provides access to root tissue and accommodates subterranean insect herbivores. Using this system, feeding performance and plant tissue damage by the root herbivore Bradysia (fungus gnat) were evaluated. Larval feeding was found to reduce Arabidopsis root biomass and water uptake. Furthermore, we have characterized a root-specific terpene synthase AtTPS08, which is responsible for the constitutive formation of the novel volatile diterpene compound, rhizathalene, in Arabidopsis roots. Rhizathalene synthase is a class I diterpene synthase that has high affinity for the substrate geranylgeranyl diphosphate (GGPP) and is targeted to the root leucoplast. Expression of the β-glucuronidase (GUS) reporter gene fused to the upstream genomic region of AtTPS08 demonstrated constitutive promoter activity in the root vascular tissue and root tips. Using the established bioassay with Arabidopsis and Bradysia larvae, in aeroponic culture we could show that roots deficient in rhizathalene synthesis were more susceptible to herbivory. Our work provides in vivo-evidence that diterpene compounds are involved in belowground direct defense against root-feeding insects. Future work is still required to improve our understanding of plant root defense. This study has provided a basis for future investigations on the biochemistry, molecular regulation and defensive function of Arabidopsis root chemicals in interaction with both above- and belowground herbivores (and pathogens).
Ph. D.
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11

Rolland, Steven. "Mise en évidence de gènes d'amibes libres impliqués dans l'interaction avec des bactéries intracellulaires." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2281.

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Les amibes libres sont des protistes qui colonisent des systèmes aqueux naturels ou artificiels. Certaines souches parmi le genre Acanthamoeba sont responsables de pathologie infectieuse chez l’Homme. Par ailleurs, en réponse à des stress environnementaux, les amibes se différencient en une forme de résistance appelée kyste, les protégeant ainsi contre les conditions de vie défavorable. Les amibes libres sont décrites comme des réservoirs environnementaux pour de nombreux pathogène de l’Homme, telle que la bactérie Legionella pneumophila, agent responsable d’une forme grave de pneumonie : la légionellose. Durant ma thèse, nous nous sommes intéressés aux gènes d’amibes libres pouvant être impliqués dans la biologie de l’amibe, notamment l’enkystement, et lors de l’interaction avec L. pneumophila. Pour cela, plusieurs protéines d’A. castellanii ont été sélectionnées à partir d’une analyse protéomique d’amibes infectées par cette bactérie. La surexpression de ces gènes dans l’amibe n’affecte pas la croissance intracellulaire de L. pneumophila. Cependant, la surexpression de deux de ces gènes inhibe partiellement le processus d’enkystement. L’une d’entre elles, la protéine Erat, a été analysée plus en détails. C’est une N-acétyltransferase-like de la famille des GNATs, d’origine possiblement procaryotique, et dont l’expression est fortement réprimée durant l’enkystement. L’ensemble de ces travaux a permis de développer des outils moléculaires sur le modèle A. castellanii, ainsi que d’améliorer la connaissance sur la physiologie de l’amibe et notamment sur le processus d’enkystement
Free-living amoebae are protists who colonize natural and artificial environments. Some strains of the genus Acanthamoeba are human pathogens. In addition, in response to environmental stresses, amoebae can differentiate into a resistant form called cyst, protecting them from adverse conditions. Free-living amoebae are described as environmental reservoirs for many bacterial pathogens, such as Legionella pneumophila, a bacteria responsible for a serious form of pneumonia, called legionellosis. During this study, we were interested in the genes of A. castellanii that could be involved in amoebal physiology, especially encystment, and during interaction with L. pneumophila. For this purpose, several proteins of A. castellanii were selected from a proteomic analysis of L. pneumophila infected amoebae. The gene overexpression in the amoeba did not affect the intracellular growth of L. pneumophila. However, the overexpression of two of these genes partially inhibited the encystment process. One of them, the Erat protein, was analyzed in more details. It is an N-acetyltransferase-like of the GNAT family, has a potential prokaryotic origin, and its expression was strongly repressed during encystment. To conclude, this work led to the development of molecular tools on the A. castellanii model, as well as to improve knowledge on the amoebal physiology and in particular on the encystment process
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Echegaray, Wilson Erik Rubens. "Life cycle of the rove beetle, Atheta coriaria (Kraatz) (Coleoptera: Staphylinidae) and suitability as a biological control agent against the fungus gnat, Bradysia sp. nr. Coprophila (Lintner)." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13624.

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Doctor of Philosophy
Department of Entomology
Raymond A. Cloyd
The life history of the rove beetle, Atheta coriaria (Kraatz) (Coleoptera:Staphylinidae), predation against the fungus gnat Bradysia sp. nr. coprophila (Lintner) and compatibility with pesticides and plant growth regulators was investigated under laboratory conditions using Sunshine LC1 Professional Growing Mix as a substrate. Duration of life stages was 2.2, 7.1, and 7.8 days for egg, larva and pupa respectively, at 26°C, whereas total development time from egg to adult was 17.0 days. In addition, A. coriaria male and female adult longevity was 60.3 and 47.8 days. Average fecundity was 90.2 eggs per female and the number of adults produced per female was 69.1. There were no significant differences in prey consumption when using second and third instar fungus gnat larvae as prey and starved and non-starved rove beetles. Overall, predation efficacy in Petri dishes was high (70 to 80%) as fungus gnat larval density increased with 3.9, 7.0, 11.1, and 15.3 larvae consumed in 24 hours after exposure of 5, 10, 15 and 20 fungus gnat larvae to one rove beetle adult. However, lower predation rates were found at different predator:prey ratios when using 1 to 5 rove beetles and growing medium as a substrate. The direct and indirect effects of pesticides and plant growth regulators on A. coriaria were investigated under laboratory conditions. Rove beetle survival was consistently higher when adults were released 24 hours after rather than before applying pesticides. Acetamiprid, lambda-cyhalothrin, and cyfluthrin were directly harmful to rove beetle adults, whereas Beauveria bassiana, azadirachtin and organic oils were compatible with A. coriaria. Similarly, the plant growth regulators acymidol, paclobutrazol and uniconazole were not harmful to rove beetle adults. In addition, Beauveria bassiana, azadirachtin, kinoprene, organic oils, and the plant growth regulators did not negatively affect A. coriaria development. However, Beauveria bassiana did negatively affect rove beetle prey consumption. This study demonstrated that A. coriaria is not compatible with the pesticides acetamiprid, lambda-cyhalothrin and cyfluthrin, whereas there is compatibility with organic oils, Beauveria bassiana, azadirachtin, and the plant growth regulators. As such, these compounds may be used in combination with A. coriaria in greenhouse production systems.
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Jackson, Sarah Marie. "Assessment of Implicit Attitudes Toward Women Faculty in Science, Technology, Engineering, and Math." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1324269233.

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14

Biarrotte-Sorin, Sabrina. "Etudes structurales de nouvelles cibles thérapeutiques : la tranférase FemX de Weissella viridescens et la L,D-transpeptidase d' Enterococcus faecium." Paris 7, 2005. http://www.theses.fr/2005PA077091.

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15

Flynn, Anita M., Rodney A. Brooks, and Lee S. Tavrow. "Twilight Zones and Cornerstones: A Gnat Robot Double Feature." 1989. http://hdl.handle.net/1721.1/6019.

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We want to build tiny gnat-sized robots, a millimeter or two in diameter. They will be cheap, disposable, totally self-contained autonomous agents able to do useful things in the world. This paper consists of two parts. The first describes why we want to build them. The second is a technical outline of how to go about it. Gnat robots are going to change the world.
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Flynn, Anita M., Lee S. Tavrow, Stephen F. Bart, and Rodney A. Brooks. "Piezoelectric Micromotors for Microrobots." 1991. http://hdl.handle.net/1721.1/5989.

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By combining new robot control systems with piezoelectric motors and micromechanics, we propose creating micromechanical systems which are small, cheap and completely autonomous. We have fabricated small - a few millimeters in diameter - piezoelectric motors using ferroelectric thin films and consisting of two pieces: a stator and a rotor. The stationary stator includes a piezoelectric film in which we induce bending in the form of a traveling wave. Anything which sits atop the stator is propelled by the wave. A small glass lens placed upon the stator becomes the spinning rotor. Using thin films of PZT on silicon nitride memebranes, various types of actuator structures have been fabricated.
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17

Brooks, Rodney A., and Anita M. Flynn. "Fast, Cheap and Out of Control." 1989. http://hdl.handle.net/1721.1/6010.

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Spur-of-the-moment planetary exploration missions are within our reach. Complex systems and complex missions usually take years of planning and force launches to become incredibly expensive. We argue here for cheap, fast missions using large numbers of mass produced simple autonomous robots that are small by today's standards, perhaps 1 to 2kg. We suggest that within a few years it will be possible, at modest cost, to invade a planet with millions of tiny robots.
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18

Neubauer, Julie. "Structural Analysis of the N-terminal Acetyltransferase A Complex." Diss., 2012. http://hdl.handle.net/10161/6146.

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19

Сірик, Володимир Васильович. "Біотопи розвитку гнусу в Запорізькій області." Магістерська робота, 2021. https://dspace.znu.edu.ua/jspui/handle/12345/5437.

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Сірик В. В. Біотопи розвитку гнусу в Запорізькій області : кваліфікаційна робота магістра спеціальності 101 "Екологія" / наук. керівник В. В. Горбань. Запоріжжя : ЗНУ, 2021. 69 с.
UA : Кваліфікаційна робота “Біотопи розвитку гнусу в Запорізькій області” виконана на 69 сторінках машинописного тексту, містить 5 рисунків, 4 таблиці, використано 68 літературних джерел. Об’єкт дослідження: гнус. Метою роботи було з’ясувати біотопи розвитку та видовий склад гнусу Запорізької області. Завданням роботи було: зробити аналіз фауни гнусу Запорізької області; визначити масовість основних компонентів гнусу; розробити класифікацію біотопів розвитку гнусу. Методи дослідження: загальноприйняті методики ентомологічних досліджень, відбору матеріалу у польових умовах, лабораторного експерименту та статичної обробки інформації. В роботі проаналізовано сучасний стан фауни гнусу в Запорізькій області. Новизна та актуальність досліджень полягає у тому, що подібні дослідження дозволять встановити і прогнозувати поширення ектопаразитами небезпечних трансмісивних захворювань у біогеоценозах Запорізької області. Значущість роботи полягає в тому, що отримані результати можуть будь використані ентомологами Запорізької області для ефективного проведення заходів із обмеження чисельності гнусу в області.
EN : Qualification work "Biotopes of the development of filth in the Zaporozhye region" is performed on 69 pages of typewritten text, contains 5 figures, 4 tables, used 68 literature sources. Object of research: gnat. The aim of the work was to find out the biotopes of development and species composition of the filth of Zaporozhye region. The task of the work was: to analyze the fauna of the city and natural areas, namely the island of Khortytsia and the zone of influence of the upper Kakhovka Reservoir), to determine the mass of the main components of filth, to develop a classification of habitats. Research methods: generally accepted methods of entomological research, selection of material in the field, laboratory experiment and static information processing. The current state of the disgusting fauna in the Zaporizhia region is analyzed in the work. The novelty and relevance of the study is that such studies will establish and predict the spread of ectoparasites of dangerous transmissible diseases in the biogeocenoses of Zaporozhye region. The significance of the work is that the obtained results can be used by entomologists of Zaporizhia region for effective measures to limit the number of disgust in the region.
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