732 resultados para Nun moth


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In isolation and characterization studies, expression level U1 and U2 snRNA isoforms were obtained from the 5th instar larval stage silk gland (SG). The DNA content of the SG cells is approximately 200,000-fold higher compared to the usual (2N) somatic cells of B. mori due to endoreduplication. In this study, the existence of U1 and U2 snRNA isoforms in the SG of the organism is investigated. Bombyx mori U1 and U2-specific RT-PCR libraries from the silk gland were generated. Five U1 and eight U2 isoforms were isolated and characterized. Nucleotide differences, structural alterations, as well as protein and RNA interaction sites were analyzed in these variants. For the U1 snRNA variants, they were compared to the previously reported BmN isoforms. In all these U-snRNA variants, polymorphic sites do not predominate at the core of known functional sequences, which were interspecifically conserved. Variant sites and inter-species differences are located in moderately conserved regions. Free energy (ΔG) values for the entire U1 and U2 snRNA secondary structures and for the individual stem/loops domains of the isoforms were generated and compared to determine their structural stability. This will be the first time that U1 and U2 variants are shown specific for a development stage (larval) other than embryonic or adult. ^ Using phylogenetic analysis, evolutionary trees were generated for the U1 and U2 snRNAs using animal, plant, protista and fungal species. The resulting trees were boostrapped for robustness and rooted with the self-splicing RNA group II intron sequence from the cyanobacterium Calothrix. Using phylogenetic analyses, possible structural and functional evolutionary interdependence between the U1 and U2 snRNAs was investigated. ^

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Fil: Pis Diez, Nayla. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.

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Fil: Svampa, Maristella. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación. Instituto de Investigaciones en Humanidades y Ciencias Sociales (UNLP-CONICET); Argentina.

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Fliegende Insekten orientieren sich in ihrer Umwelt mit Hilfe ihres hoch entwickelten olfaktorischen Systems. Es ermöglicht ihnen das Auffinden geeigneter Futter- und Eiablageplätze und ist unverzichtbar bei der innerartlichen Kommunikation. Der Geruchssinn muss dabei gleichzeitig sehr schnell und sensitiv sein um selbst geringste Mengen, z.B. des arteigenen Sexualpheromons, wahrnehmen zu können. Spezifische olfaktorische Rezeptoren (ORs) zur Detektion dieser Duftstoffe werden zusammen mit einem hoch konservierten Co-Rezeptor (Orco) in olfaktorischen Rezeptorneuronen (ORNs) auf den Insektenantennen exprimiert. Sie gehören zu den 7 Transmembran Rezeptoren, zeigen jedoch eine invertierte Membrantopologie im Vergleich zu den ORs der Vertebraten. Darüber hinaus bildet der OR/Orco-Komplex einen spontanaktiven Kationenkanal, die Bindung an ein G Protein ist allerdings umstritten. Daher ist noch ungeklärt, ob die Duftstoffbindung zu einer ionotropen Aktivierung des OR/Orco Kanals führt oder ob metabotrope Mechanismen die Bildung von zyklischem Adenosinmonophosphat (cAMP) oder Inositol 1,4,5-trisphosphat (IP3) bewirken. Mit Hilfe von extrazellulären Ableitungen einzelner Trichoidsensillen (tip recordings) auf den Antennen männlicher Manduca sexta wurde die Rolle von Orco sowie die Beteiligung einer Phospholipase Cβ (PLCβ)-abhängigen Transduktionskaskade untersucht. Es konnte gezeigt werden, dass die durch VUAA1 induzierte Spontanaktivität der ORNs durch OLC15 inhibiert und Orco somit kompetitiv gehemmt wurde. Eine Inhibition von Orco sollte die Antwort auf kurze Pheromonpulse sofort reduzieren, sollte die Transduktion über die Aktivierung des OR/Orco Kanals erfolgen. Die Ergebnisse dieser Arbeit zeigten jedoch keine Beeinflussung der primären Pheromonantwort, vielmehr wurde die späte, langanhaltende Antwort reduziert. Die ebenfalls als Orco-Antagonisten charakterisierten Amiloride MIA und HMA beeinflussen offensichtlich weitere Ziele, da eine substanz- und zeitgeberzeitabhängige Reduzierung der primären Antwort auftrat. Zusätzlich wurde die primäre Pheromonantwort durch die Inhibierung der PLCβ und der Proteinkinase C (PKC), sowie durch die Verwendung zweier Diacylglycerol (DAG)- Derivate signifikant beeinflusst. Hierbei zeigte die Inhibierung von PLCβ und PKC zeitgeberzeitabhängige Unterschiede in der Stärke der Antwortreduktion. Auch die Applikation des DAG-Derivates DOG reduzierte die Pheromonantwort, während die Zugabe von OAG die ORN Aktivität steigern oder reduzieren konnte, abhängig von der verwendeten Derivatkonzentration und der Pheromonkonzentration. Die Ergebnisse dieser Arbeit deuten somit auf einen metabotropen, sehr wahrscheinlich PLCβ-abhängigen Mechanismus für die Pheromontransduktion bei Manduca sexta.

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A new species of Trichogramma Westwood (Hymenoptera: Trichogrammatidae) parasitizing eggs of the golden twin-spot moth (or tomato looper) Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) on banana crops in the Canary Islands, Spain, is described as Trichogramma canariensis del Pino & Polaszek, sp.n. The new species is closely related to T. brassicae Bezdenko. Limited aspects of morphology, coupled with ITS2 and COI sequences and reproductive data are presented to distinguish T. canariensis sp.n. from T. brassicae.

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Wahrscheinlich war es ja nur ein Versuch einer alteingesessenen Institution der Massenmedien, sich bei „den Leuten, die man früher ‚das Publikum‘ nannte“ („the people formerly known as the audience“; Rosen, 2006, n.pag.) wieder einzuschmeicheln. Dennoch, die Anerkennung des kollektiven „You“ in YouTube und anderen kollaborativen Onlineplattformen als Person des Jahres durch das amerikanische Magazin Time (Grossman, 2007) liefert ein weiteres Indiz für die wachsende Bedeutung solcher Projekte zur gemeinschaftlichen Produktion und Distribution von Inhalten. Kreative Websites wie Flickr und YouTube, kollaborative Wissenssammlungen von Wikipedia über Digg bis zu Google Earth, nutzergesteuerte Diskussionen in Slashdot, OhmyNews, und der allgemeinen Blogosphäre, aber auch die Softwareentwicklungsgemeinschaften im Open‐Source‐Bereich – sie alle dienen als Beispiele für diese nun etablierten Trend zur Entwicklung neuer Produktions‐, Geschäfts‐, Gemeinschafts‐ und Selbstlenkungsmodelle, die wesentlich durch zunehmend komplexere Web‐2.0‐Tools unterstützt werden. Hinter diesen Beispielen wird eine allgemeiner Tendenz sichtbar, die aus ökonomischer Sicht bereits von Yochai Benkler als „commons‐based peer production“ (2006), und von Eric von Hippel als „democratizing innovation" (2005) beschrieben worden ist. Henry Jenkins spricht zudem von einer „convergence culture“ (2006), in der solche nutzergesteuerten Projekte operieren, und es können auch Verbindungen zwischen diesen stärker aktive gewordenen Nutzern und Alvin Tofflers professionellen Konsumenten, den „Prosumers“ ziehen (1971).

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Dutch-born Australian director, Rolf de Heer, is Australia's most successful and unpredictable film-maker, with thirteen feature films of widely varying style and genre to his name. Arising from the author's 2006 - 2009 PhD research at the Queensland University of Technology (which focussed on the psychoanalytic use of sound in his films), and a fixed term Research Fellowship at the National Film and Sound Archive in Canberra, Australia, "Dutch Tilt, Aussie Auteur: The Films of Rolf de Heer" was first published in 2009 by VDM in Saarbrucken, Germany. This second edition addresses de Heer's additional film-making since 2009, and as with the first edition, is an auteur analysis of the thirteen feature films he has directed (and mostly written and produced). The book explores the theoretical instability of the concept of auteurism and concludes that there is a signature world view to be detected in his oeuvre, and that de Heer (quite possibly unconsciously) promotes unlikely protagonists who are non-hyper masculine, child-like and nurturing, as opposed to the typical Hollywood hero who is macho, exploitative and hyper masculine. Rolf de Heer was born in Heemskerk, Holland, in 1951 and migrated to Australia with his family in 1959. He spent seven years working for the ABC before gaining entry to Australia's Film, Television and Radio School, where he studied Producing and Directing. From his debut feature film after graduating, the children's story about the restoration of a Tiger Moth biplane, "Tail of a Tiger" (1984) to his breakout cult sensation "Bad Boy Bubby" (1993) which "tore Venice [Film Festival] apart" to the first Aboriginal Australian language film "Ten Canoes" (2006) which scooped the pool at the Australian Film Institute awards, de Heer has consistently proven himself unpredictable. This analysis of his widely disparate films, however, suggests that Australia's most innovative film-maker has a signature pre-occupation with giving a voice to marginalised, non-hyper masculine protagonists. Demonstrating a propensity to write and direct in a European-like style, his 'Dutch tilt' is very much not Hollywood, but is nevertheless representative of a typically Aussie world-view.

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Allyson Reynolds, for many years now, has been a keen student of nature. Nature’s forms have always been important to her work, but it would be wrong to see Reynolds as simply transcribing directly from the natural world. For this artist, nature and the natural world represents an elusive invitation and so Reynolds doesn’t so much paint from nature, although resemblance and imitation are clearly evident, as work to render visually and emotionally tangible this invitation. And for a viewer this is no small thing as the invitation is to become attuned and connect with nature as it exists in ourselves, that is to see as nature. Reynolds’ is inviting us as viewers to connect and participate with the nature of nature that is evident in ourselves through the act of perceiving. Reynolds’ work can do this because it is a work born of deep evocation. The sensibility from which it emerges or is transacted is poetic, intensely so, but more than that it works to make of viewing an act of poetry, through a celebration of seeing. Reynolds evocation is born of a deep feeling towards and contemplation of the natural world - it is as though the world lives in her and is now a seamless part of her creative vocabulary. In such personal work there is a profoundly felt and revealed sense of the intimate and like true intimacy it revels in both its dark and quiet, as well as its playful and light, aspects. What is special about Reynolds’ visual poetry is that it able to render this intimacy so accessible. It is an accessibility that is available for the viewer who is able to not only look but also surrender to that looking, accepting and working with the flow of thoughts and associations it occasions...

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Abstract. 1. Learning may enable insects to obtain nectar from flowers more efficiently. Learning in nectar foraging has been shown primarily in studies of bees and butterflies. Here, learning is demonstrated in the nectar foraging behaviour of a noctuid moth, Helicoverpa armigera. 2. The present studies show that: (1) previous experience with a flowering host species increases the probability of that species being selected for nectar foraging, and (2) previous experience of a particular flower type (food source at bottom or top of the corolla tube) increases the likelihood of the food source being found when that flower type is being searched. 3. The implications of these findings for understanding the pattern of oviposition observed in wild populations of this important pest species are discussed.

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Recent experimental evidence has shown that learning occurs in the host selection behaviour of Helicoverpa armigera (Hübner), one of the world‘s most important agricultural pests. This paper discusses how the occurrence of learning changes our understanding of the host selection behaviour of this polyphagous moth. Host preferences determined from previous laboratory studies may be vastly different from preferences exhibited by moths in the field, where the abundance of particular hosts may be more likely to determine host preference. In support of this prediction, a number of field studies have shown that the ‘attractiveness’ of different hosts for H. armigera oviposition may depend on the relative abundance of these host species. Insect learning may play a fundamental role in the design and application of present and future integrated pest management strategies such as the use of host volatiles, trap crops and resistant crop varieties for monitoring and controlling this important pest species