411 resultados para diamondback moth (DBM)


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Background: In the course of evolution butterflies and moths developed two different reproductive behaviors. Whereas butterflies rely on visual stimuli for mate location, moths use the"female calling plus male seduction" system, in which females release long-range sex pheromones to attract conspecific males. There are few exceptions from this pattern but in all cases known female moths possess sex pheromone glands which apparently have been lost in female butterflies. In the day-flying moth family Castniidae ("butterfly-moths"), which includes some important crop pests, no pheromones have been found so far. Methodology/Principal Findings: Using a multidisciplinary approach we described the steps involved in the courtship of P. archon, showing that visual cues are the only ones used for mate location; showed that the morphology and fine structure of the antennae of this moth are strikingly similar to those of butterflies, with male sensilla apparently not suited to detect female-released long range pheromones; showed that its females lack pheromone-producing glands, and identified three compounds as putative male sex pheromone (MSP) components of P. archon, released from the proximal halves of male forewings and hindwings. Conclusions/Significance: This study provides evidence for the first time in Lepidoptera that females of a moth do not produce any pheromone to attract males, and that mate location is achieved only visually by patrolling males, which may release a pheromone at short distance, putatively a mixture of Z,E-farnesal, E,E-farnesal, and (E,Z)-2,13-octadecadienol. The outlined behavior, long thought to be unique to butterflies, is likely to be widespread in Castniidae implying a novel, unparalleled butterfly-like reproductive behavior in moths. This will also have practical implications in applied entomology since it signifies that the monitoring/control of castniid pests should not be based on the use of female-produced pheromones, as it is usually done in many moths.

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For the past 10 years, mini-host models and in particular the greater wax moth Galleria mellonella have tended to become a surrogate for murine models of fungal infection mainly due to cost, ethical constraints and ease of use. Thus, methods to better assess the fungal pathogenesis in G. mellonella need to be developed. In this study, we implemented the detection of Candida albicans cells expressing the Gaussia princeps luciferase in its cell wall in infected larvae of G. mellonella. We demonstrated that detection and quantification of luminescence in the pulp of infected larvae is a reliable method to perform drug efficacy and C. albicans virulence assays as compared to fungal burden assay. Since the linearity of the bioluminescent signal, as compared to the CFU counts, has a correlation of R(2) = 0.62 and that this method is twice faster and less labor intensive than classical fungal burden assays, it could be applied to large scale studies. We next visualized and followed C. albicans infection in living G. mellonella larvae using a non-toxic and water-soluble coelenterazine formulation and a CCD camera that is commonly used for chemoluminescence signal detection. This work allowed us to follow for the first time C. albicans course of infection in G. mellonella during 4 days.

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Seloste artikkelista: Vanhanen, H., Veteli, T. O., Päivinen, S., Kellomäki, S. & Niemelä, P. 2007. Climate change and range shifts in two insect defoliators: gypsy moth and nun moth - a model study. Silva Fennica 41 (4) : 621-638

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Synthetic procedures, characterization and luminescent properties of Eu3+ and Tb3+ ions supported on silica gel functionalized with beta-diketones are presented. The functionalization with propyl benzoyltrifluoroacetone (BPG), dibenzoylmethane (DBM) and hexafluoroacetone (HPG), leads to new luminescent materials which photophysical properties depend on the group substituent in the beta-diketone. These systems were evaluated in terms of luminescence and lifetime of the Eu3+ and Tb3+ ions. Silica functionalization was confirmed by TGA and Elemental Analysis. The sample contents of ions were from 0,2 to 0,3 % (w/w).

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This work aimed at the synthesis and characterization of particles of modified silica containing the organic filter dibenzoylmethane (DBM) by the hydrolytic sol-gel method, with modifications to the Stöber route. The structures of the resulting Xerogels were characterized by diffuse reflectance UV-VIS spectroscopy in the solid state, infrared absorption spectroscopy, Scanning Electron Microscopy (SEM) and 29Si Nuclear Magnetic Resonance (29Si NRM). The results showed favorable formation of hybrid organic-inorganic nanoparticles with efficient absorption/reflectance of radiation in the UV / VIS range, which enables their potential use as sunscreen.

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In this thesis a closer look at ZigBee wireless network protocol was made and a ZigBee evaluation device was designed and built for testing it. ZigBee is a digital wireless network technology published in 2004, which was developed for wireless control and automation systems. It is based on the IEEE 802.15.4-2003 standard, and its aim was to create a reliable wireless networking protocol with secure data transmissions, low power consumption and low manufacturing costs. The low power consumption requirement has also led to a slow data rate and a short range, but in a ZigBee network individual network devices can route messages to each other, so short range is not a problem. In automation and control systems a fast data rate is not usually an important requirement either. ZigBee network can form automatically and one ZigBee network can theoretically include thousands of devices, all of which can communicate with each other. ZigBee network is also self-healing, so an individual device dropping out of the network, like breaking down, does not affect functionality of the network. Evaluation device was designed and implemented in four different versions, which were tested with six different antenna designs. All antennas were tested at a range of 100 meters in an open terrain using two different frequencies and transmission powers. Also a range test was performed for selected antennas using transmission power of 4,5 dBm, which was maximum power of the ZigBee chip used in the evaluation device. Range test resulted in a measured range of several hundred meters, which can be considered as a good result for a short-range technology.

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In this thesis, I conduct a series of molecular systematic studies on the large phytophagous moth superfamily Noctuoidea (Insecta, Lepidoptera) to clarify deep divergences and evolutionary affinities of the group, based on material from every zoogeographic region of the globe. Noctuoidea are the most speciose radiations of butterflies and moths on earth, comprising about a quarter of all lepidopteran diversity. The general aim of these studies was to apply suitably conservative genetic markers (DNA sequences of mitochondrial—mtDNA—and nuclear gene— nDNA—regions) to reconstruct, as the initial step, a robust skeleton phylogenetic hypothesis for the superfamily, then build up robust phylogenetic frameworks for those circumscribed monophyletic entities (i.e., families), as well as clarifying the internal classification of monophyletic lineages (subfamilies and tribes), to develop an understanding of the major lineages at various taxonomic levels within the superfamily Noctuoidea, and their inter-relationships. The approaches applied included: i) stabilizing a robust family-level classification for the superfamily; ii) resolving the phylogeny of the most speciose radiation of Noctuoidea: the family Erebidae; iii) reconstruction of ancestral feeding behaviors and evolution of the vampire moths (Erebidae, Calpinae); iv) elucidating the evolutionary relationships within the family Nolidae and v) clarifying the basal lineages of Noctuidae sensu stricto. Thus, in this thesis I present a wellresolved molecular phylogenetic hypothesis for higher taxa of Noctuoidea consisting of six strongly supported families: Oenosandridae, Notodontidae, Euteliidae, Erebidae, Nolidae, and Noctuidae. The studies in my thesis highlight the importance of molecular data in systematic and phylogenetic studies, in particular DNA sequences of nuclear genes, and an extensive sampling strategy to include representatives of all known major lineages of entire world fauna of Noctuoidea from every biogeographic region. This is crucial, especially when the model organism is as species-rich, highly diverse, cosmopolitan and heterogeneous as the Noctuoidea, traits that represent obstacles to the use of morphology at this taxonomic level.

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Tutkimuksen aiheena on Venäläisten rynnäkkökoneiden ja monitoimihävittäjien sensorija omasuojajärjestelmien tekninen tarkastelu ja niiden vaikutuksen ilmasta-maahan suorituskykyyn. Tutkimustyö käsittelee venäläisten rynnäkkökoneiden SU-24 ja SU-25 sekä monitoimihävittäjien SU-27SM ja MiG-29SMT sensoreita ja omasuojajärjestelmiä sekä käytettäviä asejärjestelmiä. Tutkimuksessa muodostetaan sensori-, omasuoja- ja asejärjestelmien avulla kokonaiskuva koneiden ilmasta-maahan suorituskyvystä. Tutkimuksessa pyritään vastaamaan seuraaviin kysymyksiin: Mistä muodostuu ilmastamaahan suorituskyky? Mitkä ovat Venäjän ilmavoimien yleisimmät rynnäkkökoneet ja monitoimihävittäjät ja mitä järjestelmiä niissä on? Mikä on koneen optimaalinen suorituskyky tarkasteltavaa kohdetta vastaan? Tutkimuksen sivutuotteena vastataan kysymykseen: Mikä on panssarivaunun tutkaheräte dBm² ja m² suureina? Tutkimuksen tutkimusmenetelminä on käytetty kirjallisuustutkimusta ja vertailevaa tutkimusmenetelmää. Järjestelmien julkisissa lähteissä ilmoitettu suorituskyky on pyritty todentamaan matemaattisesti laskien. PVTT:ssa toteutettujen simulointien avulla on voitu laskea lavettien tutkien havaitsemisetäisyyksiä. Tutkimustyön lähdeaineisto pohjautuu julkisiin lähteisiin. Suurin osa tutkimustyön lähteistä on internetistä julkaistuja artikkeleita ja teknisiä raportteja. Lähdeaineistoa lukemalla, vertailemalla ja analysoimalla on koostettu tietoa aiheesta. Rynnäkkökoneiden ja monitoimihävittäjien tutkien suorituskyvyn muodostamiseksi toteutettiin panssarivaunun 3Dmallin tutkaherätteen simulointi. Tulosten perusteella voidaan vertailla käytössä olevien tutkien suorituskykyä. Ilma-aseen suorituskyky pohjautuu pääosin käytettäviin sensoreihin ja laitteisiin. Sensorijärjestelmillä suunnistetaan, paikannetaan maali, osoitetaan maali käytettävällä asejärjestelmällä ja ohjataan asejärjestelmä haluttuun maaliin. Omasuojajärjestelmillä mahdollistetaan ilma-aseen toimiminen alueella vallitsevasta uhkasta huolimatta. Omasuojajärjestelmät koostuvat varoittimista ja aktiivisista vastatoimenpidejärjestelmistä.. Ilmasta-maahan suorituskykyyn vaikuttavat oleellisesti lavetin kyky havaita kohteita tutkalla, lämpökameralla ja TV-kameralla. Ilmasta-maahan suorituskykyyn vaikuttaa oleellisesti miltä etäisyydeltä kohde voidaan havaita ja miltä etäisyydeltä asejärjestelmä voidaan laukaista. Tutkimuksen perusteella voidaan todeta Venäjän ilmavoimilla olevan suorituskyvyltään hyvällä tasolla olevia koneita. Suorituskykyisten koneiden lukumäärä on hyvin pieni. Suurin osa operatiivisessa käytössä olevista koneista ei ole suorituskyvyltään riittävällä tasolla. Modernisaatioiden myötä Venäjän ilmavoimat saavuttavat riittävän suorituskyvyn rynnäkkökoneille ja monitoimihävittäjille.

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(Biologia floral de cinco espécies de Passiflora L. (Passifloraceae) em mata semidecídua). O estudo da biologia floral de cinco espécies de Passiflora foi feito em uma mata de planalto em Campinas, São Paulo. Passiflora alata, P. amethystina e P. miersii apresentam flores de cor púrpura a violeta e corona variegada. As flores são diurnas, perfumadas, autoincompatíveis e polinizadas por abelhas de grande porte. Passiflora amethystina e P. miersii diferem de P. alata por apresentarem filamentos livres no opérculo, que em P. alata é horizontal e denticulado. Estas diferenças no opérculo promovem comportamentos característicos das abelhas durante as visitas. Passiflora suberosa possui flores verde-amareladas e opérculo plicado. As flores são diurnas, inodoras, autocompatíveis e polinizadas por vespas. Em P. capsularis as flores são brancas e o opérculo é plicado. As flores são noturnas, perfumadas, autocompatíveis e possivelmente polinizadas por mariposas. O opérculo plicado das duas últimas espécies permite que os visitantes tenham fácil acesso ao néctar.

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Nos últimos anos, vem crescendo o interesse em alimentos com baixo índice de calorias. Nos métodos tradicionais de extração de lipídeos com solventes orgânicos, devido as condições de extração, a integridade dos compostos extraídos e da matriz pode ser afetada pela decomposição térmica ou por contaminação pelo solvente. A extração com fluido supercrítico (EFSC) pode proporcionar um método alternativo para remover lipídeos, sem que haja redução significativa nas propriedades organolépticas do produto. O objetivo deste trabalho é extrair parcialmente o óleo contido na amêndoa da castanha de caju (Anacardium occidentale) com dióxido de carbono (CO2) supercrítico em condições de pressão de 100-170 bar e temperatura de 40-80 (C, para obter um produto de valor calórico reduzido que poderá ser usado como substituto para o amendoim e outras amêndoas na indústria de confeitos. Os experimentos foram realizados em um extrator de 300 ml, dispondo de sistemas de agitação magnética e variação de temperatura. Os resultados experimentais mostraram que o aumento da pressão acarretou um aumento na eficiência de extração. O efeito da temperatura foi o mesmo porém menos significativo.

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O fracionamento do farelo de milho desengordurado (fubá grosso), subproduto do processamento industrial do milho, para obtenção de frações de amido, proteínas e fibras, utilizando métodos físicos e químicos, foi investigado. O fracionamento do fubá grosso por meio de tratamento químico com soluções de bissulfito de sódio e de etanol, foi satisfatório, pois produziu fração de amido com aceitável rendimento; já o fracionamento físico não foi muito eficiente, visto que não produziu fração enriquecida de proteínas e amido. Tanto o fubá grosso como as frações obtidas, foram caracterizados por meio de CLAE (Cromatografia Líquida de Alta Eficiência) e Análise Térmica (TG, DTG e DSC). O fubá grosso possui mais de 50% de amido (CLAE), e perda de 52% de sua massa entre 270 e 450ºC (TG e DTG). O estudo cinético, a partir de curvas DSC, mostrou que os processos de gelatinização da fração de amido e de desnaturação da fração de proteínas são eventos endotérmicos, com diferentes valores de entalpia e de energia de ativação.

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The Consumers' interest for products with caloric reduction has increased, and their development is a technological challenge. The consumption of cakes has grown in importance and the demand for dietary products has stimulated the use of sweeteners and the optimization of bakery products. The consumption of fibers is related to chronic diseases prevention. Pumpkin seeds (maximum Cucurbita, L.), rich in fibers, can be used as a source of fiber in food products. A gluten-free diet is not easy to follow since gluten free products are not always available. The objective of this work was to perform a physicochemical characterization of cakes prepared with flours blends (FB) based on Pumpkin Seed Flour (PSF). The cakes were elaborated with FB in the ratios of 30:70 (C30) and 40:60 (C40) of PSF and cornstarch (CS), respectively. The results showed gluten absence and near-neutral pH. The chemical analysis of C30 and B40 showed increase of ashes, lipids, proteins, and insoluble dietary fiber and a decrease in the content of carbohydrates and calories. The chemical composition of C40 presented the greatest content of lipids, proteins, and dietary fibers, the lowest content of calories, and the best physical parameters. Therefore, both products proved suitable for human consumption.

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The gypsy moth, Lymantria dispar, a major defoliator of broad leaf trees, was accidentally introduced into North America in 1869. Much interest has been generated regarding the potential of using natural pathogens for biological control of this insect. One of these pathogens, a highly specific fungus, Entomophaga maimaiga, was accredited with causing major epizootics in populations of gypsy moth across the north-eastern United States in 1989 and 1990 and is thought to be spreading northwards into Canada. This study examined gypsy moth population densities in the Niagara Region. The fungus, .E.. maimaiga, was artificially introduced into one site and the resulting mortality in host populations was noted over two years. The relationship between fungal mortality, host population density and occurrence of another pathogen, the nuclear polyhedrosis virus (NPV), was assessed. Gypsy moth population density was assessed by counting egg masses in 0.01 hectare (ha) study plots in six areas, namely Louth, Queenston, Niagara-on-the-Lake, Shorthills Provincial Park, Chippawa Creek and Willoughby Marsh. High variability in density was seen among sites. Willoughby Marsh and Chippawa Creek, the sites with the greatest variability, were selected for more intensive study. The pathogenicity of E. maimaiga was established in laboratory trials. Fungal-infected gypsy moth larvae were then released into experimental plots of varying host density in Willoughby Marsh in 1992. These larvae served as the inoculum to infect field larvae. Other larvae were injected with culture medium only and released into control plots also of varying host density. Later, field larvae were collected and assessed for the presence of .E.. maimaiga and NPV. A greater proportion of larvae were infected from experimental plots than from control plots indicating that the experimental augmentation had been successful. There was no relationship between host density and the proportion of infected larvae in either experimental or control plots. In 1992, 86% of larvae were positive for NPV. Presence and intensity of NPV infection was independent of fungal presence, plot type or interaction of these two factors. Sampling was carried out in the summer of 1993, the year after the introduction, to evaluate the persistence of the pathogen in the environment. Almost 50% of all larvae were infected with the fungus. There was no difference between control and experimental plots. Data collected from Willoughby Marsh indicated that there was no correlation between the proportion of larvae infected with the fungus and host population density in either experimental or control plots. About 10% of larvae collected from a nearby site, Chippawa Creek, were also positive for .E.. maimaiga suggesting that low levels of .E.. maimaiga probably occurred naturally in the area. In 1993, 9.6% of larvae were positive for NPV. Again, presence or absence of NPV infection was independent of fungal presence plot type or interaction of these two factors. In conclusion, gypsy moth population densities were highly variable between and within sites in the Niagara Region. The introduction of the pathogenic fungus, .E.. maimaiga, into Willoughby Marsh in 1992 was successful and the fungus was again evident in 1993. There was no evidence for existence of a relationship between fungal mortality and gypsy moth density or occurrence of NPV. The results from this study are discussed with respect to the use of .E.. maimaiga in gypsy moth management programs.

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While nitrogen is critical for all plants, they are unable to utilize organically bound nitrogen in soils. Therefore, the majority of plants obtain useable nitrogen through nitrogen fixing bacteria and the microbial decomposition of organic matter. In the majority of cases, symbiotic microorganisms directly furnish plant roots with inorganic forms of nitrogen. More than 80% of all land plants form intimate symbiotic relationships with root colonizing fungi. These common plant/fungal interactions have been defined largely through nutrient exchange, where the plant receives limiting soil nutrients, such as nitrogen, in exchange for plant derived carbon. Fungal endophytes are common plant colonizers. A number of these fungal species have a dual life cycle, meaning that they are not solely plant colonizers, but also saprophytes, insect pathogens, or plant pathogens. By using 15N labeled, Metarhizium infected, wax moth larvae (Galleria mellonella) in soil microcosms, I demonstrated that the common endophytic, insect pathogenic fungi Metarhizium spp. are able to infect living soil borne insects, and subsequently colonize plant roots and furnish ts plant host with useable, insect-derived nitrogen. In addition, I showed that another ecologically important, endophytic, insect pathogenic fungi, Beauveria bassiana, is able to transfer insect-derived nitrogen to its plant host. I demonstrated that these relationships between various plant species and endophytic, insect pathogenic fungi help to improve overall plant health. By using 13C-labeled CO2, added to airtight plant growth chambers, coupled with nuclear magnetic resosnance spectroscopy, I was able to track the movement of carbon from the atmosphere, into the plant, and finally into the root colonized fungal biomass. This indicates that Metarhizium exists in a symbiotic partnership with plants, where insect nitrogen is exchanged for plant carbon. Overall these studies provide the first evidence of nutrient exchange between an insect pathogenic fungus and plants, a relationship that has potentially useful implications on plant primary production, soil health, and overall ecosystem stability.

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Ce travail financé par l'ACDI a été réalisé au Laboratoire TRANSNUT de l'Université de Montréal (Canada)en collaboration avec le Laboratoire National de Santé Publique (Burkina Faso) et HKI-Burkina Faso.