897 resultados para Amblyomma triste nymphs


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(cont.): Cradle song : berceuse / Walter Spinney -- Andantino from Fantasia in C minor / W.A. Mozart -- Marche de fête / Edgar A. Barrell -- Minster march : from Lohengrin / R. Wagner -- Sunrise : op. 7, no. 1 / Sigfrid Karg-Elert -- Song without words = Chant sans paroles : op. 2, no. 3 / P. Tschaikowsky -- Prayer on motives from R. Wagner's Lohengrin : op. 54 / B. Sulze -- Festal march : op. 67, no. 8 / E.R. Kroeger -- Christmas march / G. Merkel -- Duke Street : postlude II / Geo. E. Whiting -- Canzonetta from the Raymond overture / A. Thomas -- Anniversary march : introducing Auld lang syne : op. 10 / J. Lawrence Ebb -- Two cradle songs = Zwei Wiegenliedchen / Herbert Botting -- Minuet from the overture to Berenice / G.F. Handel -- Funeral march = Marche funèbre : op. 35 / Franz Chopin -- March in B♭ / Wm. Faulkes -- The Son of God goes forth to war : postlude VI / Geo. E. Whiting -- Nocturne des anges : op. 18, no. 1 / George F. Vincent -- Hosanna! / Paul Wachs -- Roumanian bridal march / Herbert W. Wareing.

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Populations of the planthopper vector Perkinsiella saccharicida on sugarcane cultivars resistant (cvs Q110 and Q87), moderately resistant (cvs Q90 and Q124) and susceptible (evs NCo310 and Q 102) to Fiji disease with known field resistance scores were monitored on the plant (2000-2001) and ratoon (2001-2002) crops. In both crops, the vector population remained very low, reaching its peak in the autumn. The vector population was significantly higher on cultivars susceptible to Fiji disease than on cultivars moderately resistant and resistant to Fiji disease. The number of R saccharicida adults, nymphs and oviposition sites per plant increased with the increase in the Fiji disease susceptibility. The results suggest that under low vector density, cultivar preference by the planthopper vector mediates Fiji disease resistance in sugarcane. To obtain resistance ratings in the glasshouse that reflect field resistance, glasshouse-screening trials should be conducted under both low and high vector densities, and the cultivar preference of the planthopper vector recorded along with Fiji disease incidence.

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In recent years there has been much progress in our understanding of the phylogeny and evolution of ticks, in particular the hard ticks (Ixodidae). Indeed, a consensus about the phylogeny of the hard ticks has emerged which is quite different to the working hypothesis of 10 years ago. So that the classification reflects our knowledge of ticks, several changes to the nomenclature of ticks are imminent or have been made. One subfamily, the Hyalomminae, should be sunk, while another, the Bothriocrotoninae, has been created (Klompen, Dobson & Barker, 2002). Bothriocrotoninae, and its sole genus Bothriocroton, have been created to house an early-diverging ('basal') lineage of endemic Australian ticks that used to be in the genus Aponomma. The remaining species of the genus Aponomma have been moved to the genus Amblyomma. Thus, the name Aponomma is no longer a valid genus name. The genus Rhipicephalus is paraphyletic with respect to the genus Boophilus. Thus, the genus Boophilus has become a subgenus of the genus Rhipicephalus (Murrell & Barker, 2003). Knowledge of the phylogenetic relationships of ticks has also provided new insights into the evolution of ornateness and of their life cycles, and has allowed the historical zoogeography of ticks to be studied. Finally, we present a list of the 899 valid genus and species names of ticks as of February 2004.

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1 The herbivorous bug Heteropsylla cubana Crawford (Homoptera: Psyllidae) is a pest of the cattle fodder crop Leucaena (Leguminosae: Mimosoideae). The interaction between the psyllid and three varieties of its Leucaena host plant was investigated in relation to the apparent resistance of some Leucaena varieties (Leucaena leucocephala, Leucaena pallida and their hybrids) to attack. 2 Field trials demonstrated that adult psyllids distinguished among the different varieties of Leucaena over a distance, and were attracted to L. leucocephala in significantly higher numbers than to L. pallida or to the hybrid. Pesticide treatment increased the attractiveness of Leucaena plants, even of those deemed to be psyllid resistant. Numbers of psyllid eggs and nymphs, sampled in the field, reflect the arrival rates of adults at the three plant varieties. 3 Wavelength reflectance data of the three Leucaena varieties were not significantly different from one another, suggesting that psyllids cannot discriminate among the three plants using brightness or wavelength cues. There was a differential release of caryophyllene among the three varieties. Release of caryophyllene in L. leucocephala and the hybrid appeared to be influenced by environmental conditions. 4 Experiments demonstrated that caryophyllene (at least on its own) did not influence the behaviour of leucaena psyllids in relation to leucaena plants. 5 The results suggest that host plant volatiles cannot be dismissed as significant in the interaction between the leucaena psyllid and its Leucaena host plants. Further avenues for investigation are recommended and these are related to novel ways of understanding resistance in insect plant inter-relationships.

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We tested the phenotypic responses of larval striped marsh frogs (Limnodynastes peronii) to the odonate nymph predator, Aeshna brevistyla. When reared in the presence of dragonfly nymphs feeding upon conspecifics of L. peronii larvae the tadpoles showed a strong change in morphology. Morphological changes included an increase in total tail height, but also an unexpected marked change in head-body shape. In addition, we examined how tadpole development, as well as mass and length at metamorphosis, was affected by exposure to dragonfly nymphs. Larval development of L. peronii was strongly influenced by exposure to the predatory behaviour of dragonfly nymphs. Predator-induced tadpoles had significantly slower developmental rates than control larvae. Although metamorphs of non-exposed L. peronii were approximately 33% lighter than predator-exposed metamorphs and possessed lower jump distances, after adjusting for mass there was no difference in jump distance. The newly described morphological response may assist in more accurately relating morphological plasticity to fitness.

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The saliva of ticks (Suborder Ixodida) is critical to their survival as parasites. A tick bite should result in strong responses from the host defence systems (haemostatic, immune and inflammatory) but tick saliva appears to have evolved to counter these responses. We review current knowledge of tick saliva components, with emphasis on those molecules confirmed to be present in the secreted saliva but including some that have only been confirmed to be present in salivary glands. About 50 tick saliva proteins that are well described in the literature are discussed. These saliva components include enzymes, enzyme inhibitors, amine-binding proteins and cytokine homologues that act as anti-haemostatic, anti-inflammatory or immuno-modulatory agents. Sequence comparisons are illustrated. The importance of tick saliva and the significance of the findings to date are also discussed. (C) 2006 Elsevier Ltd. All rights reserved.

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The southern cattle tick, Boophilus microplus (Canestrini), causes annual economic losses in the hundreds of millions of dollars to cattle producers throughout the world, and ranks as the most economically important tick from a global perspective. Control failures attributable to the development of pesticide resistance have become commonplace, and novel control technologies are needed. The availability of the genome sequence will facilitate the development of these new technologies, and we are proposing sequencing to a 4-6X draft coverage. Many existing biological resources are available to facilitate a genome sequencing project, including several inbred laboratory tick strains, a database of approximate to 45,000 expressed sequence tags compiled into a B. microplus Gene Index, a bacterial artificial chromosome (BAC) library, an established B. microplus cell line, and genomic DNA suitable for library synthesis. Collaborative projects are underway to map BACs and cDNAs to specific chromosomes and to sequence selected BAC clones. When completed, the genome sequences from the cow, B. microphis, and the B. microphis-borne pathogens Babesia bovis and Anaplasma marginale will enhance studies of host-vector-pathogen systems. Genes involved in the regeneration of amputated tick limbs and transitions through developmental stages are largely unknown. Studies of these and other interesting biological questions will be advanced by tick genome sequence data. Comparative genomics offers the prospect of new insight into many, perhaps all, aspects of the biology of ticks and the pathogens they transmit to farm animals and people. The B. microplus genome sequence will fill a major gap in comparative genomics: a sequence from the Metastriata lineage of ticks. The purpose of the article is to synergize interest in and provide rationales for sequencing the genome of B. microplus and for publicizing currently available genomic resources for this tick.

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Desde tempos remotos é notória a busca da humanidade para entender e conquistar a felicidade, qualidade de vida, bem-estar e saúde na sua plenitude bio-psico-social. Assim, o objetivo geral deste estudo foi analisar as relações entre percepções de suporte (social, social no trabalho e organizacional) e bem-estar no trabalho (satisfação no trabalho, envolvimento com o trabalho e comprometimento organizacional afetivo) em trabalhadores com deficiência, pois são poucas as pesquisas sobre pessoas com deficiência (PCD). O propósito em abordar o trabalho é por ser um importante elemento de integração social e por constituir um símbolo de reconhecimento social, valorizando a capacidade de estreitar contatos e de estabelecer relações sociais. Deste estudo, participaram 44 trabalhadores com algum tipo de deficiência que atuam em cargos operacionais, técnicos e administrativos. Todos foram escolhidos por conveniência, sendo 24 (54,5%) do sexo masculino e 20 (45,5%) do sexo feminino, com idade entre 18 e 65 anos. Foi possível classificar as deficiências dos participantes em quatro categorias: deficiência nos membros superiores: 9 (20,5%) trabalhadores; deficiência nos membros inferiores: 11 (25%) trabalhadores; deficiência auditiva: 21 (47,7%) trabalhadores; deficiência visual: 3 (6,8%) trabalhadores. Para a coleta de dados foi utilizado questionário de auto-preenchimento, composto de seis escalas que avaliam satisfação no trabalho, envolvimento com o trabalho e comprometimento organizacional, além de suporte social, suportes social no trabalho e organizacional. Foram realizadas análises estatísticas descritivas, testadas diferenças entre médias, bem como calculados coeficientes de correlação entre variáveis. Os resultados apontam que em termos de satisfação no trabalho, não revelam discrepâncias entre estudos realizados com trabalhadores sem deficiências (considerados normais ). Também foi possível observar que as PCD declaram ter orgulho da empresa em que trabalham, além de estarem contentes, entusiasmadas, interessadas e animadas com a organização empregadora. O estudo revelou que as PCD obtêm de sua rede social, ajuda emocional que lhes proporciona sentimento de apoio frente às dificuldades ou carências afetivas, pois provavelmente entendam que podem contar com essa rede para comemorar realizações e sucessos, da mesma forma que receber carinho e consolo quando se frustram ou passam por algum momento triste. É possível afirmar que as PCD percebem que essa mesma rede seria capaz de lhes prover algum apoio prático, como receber informações acerca de sua saúde, talvez reabilitação, também informações para atualização profissional ou até acompanhamento do seu desenvolvimento, inclusive busca de novas oportunidades e desafios para crescimento pessoal e profissional. Os resultados desta pesquisa indicam que as PCD tendem a manter uma forte convicção de que a empresa em que trabalham preocupa-se com seu bem-estar e está disposta a oferecer ajuda diante uma necessidade. Demais resultados sinalizam que as PCD tendem a aumentar o seu vínculo com o trabalho vivenciando mais satisfação na medida em que também aumentam os suportes ofertados pela organização, pela rede social no contexto do trabalho e fora dele. A análise de todo o conteúdo confeccionado é a grande contribuição deste estudo, por ser considerado pioneiro nesta discussão, mas futuros estudos podem vir a confirmar tais resultados e corroborar com mais informações.(AU)

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En este artículo nos aproximaremos a dos poéticas que comparten trazos muy similares entre sí: la de Leopoldo María Panero y la del escritor gallego Lois Pereiro, dos figuras que renuevan la lírica del último cuarto del siglo XX. Este estudio no se centrará exclusivamente en las similitudes entre las poéticas, sino que abordará también la biografía de los dos autores, muy presente en sus creaciones literarias.

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v. 17, n. 2, p. 296-302, abr./jun. 2016.

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Vector-borne disease emergence in recent decades has been associated with different environmental drivers including changes in habitat, hosts and climate. Lyme borreliosis is among the most important vector-borne diseases in the Northern hemisphere and is an emerging disease in Scotland. Transmitted by Ixodid tick vectors between large numbers of wild vertebrate host species, Lyme borreliosis is caused by bacteria from the Borrelia burgdorferi sensu lato species group. Ecological studies can inform how environmental factors such as host abundance and community composition, habitat and landscape heterogeneity contribute to spatial and temporal variation in risk from B. burgdorferi s.l. In this thesis a range of approaches were used to investigate the effects of vertebrate host communities and individual host species as drivers of B. burgdorferi s.l. dynamics and its tick vector Ixodes ricinus. Host species differ in reservoir competence for B. burgdorferi s.l. and as hosts for ticks. Deer are incompetent transmission hosts for B. burgdorferi s.l. but are significant hosts of all life-stages of I. ricinus. Rodents and birds are important transmission hosts of B. burgdorferi s.l. and common hosts of immature life-stages of I. ricinus. In this thesis, surveys of woodland sites revealed variable effects of deer density on B. burgdorferi prevalence, from no effect (Chapter 2) to a possible ‘dilution’ effect resulting in lower prevalence at higher deer densities (Chapter 3). An invasive species in Scotland, the grey squirrel (Sciurus carolinensis), was found to host diverse genotypes of B. burgdorferi s.l. and may act as a spill-over host for strains maintained by native host species (Chapter 4). Habitat fragmentation may alter the dynamics of B. burgdorferi s.l. via effects on the host community and host movements. In this thesis, there was lack of persistence of the rodent associated genospecies of B. burgdorferi s.l. within a naturally fragmented landscape (Chapter 3). Rodent host biology, particularly population cycles and dispersal ability are likely to affect pathogen persistence and recolonization in fragmented habitats. Heterogeneity in disease dynamics can occur spatially and temporally due to differences in the host community, habitat and climatic factors. Higher numbers of I. ricinus nymphs, and a higher probability of detecting a nymph infected with B. burgdorferi s.l., were found in areas with warmer climates estimated by growing degree days (Chapter 2). The ground vegetation type associated with the highest number of I. ricinus nymphs varied between studies in this thesis (Chapter 2 & 3) and does not appear to be a reliable predictor across large areas. B. burgdorferi s.l. prevalence and genospecies composition was highly variable for the same sites sampled in subsequent years (Chapter 2). This suggests that dynamic variables such as reservoir host densities and deer should be measured as well as more static habitat and climatic factors to understand the drivers of B. burgdorferi s.l. infection in ticks. Heterogeneity in parasite loads amongst hosts is a common finding which has implications for disease ecology and management. Using a 17-year data set for tick infestations in a wild bird community in Scotland, different effects of age and sex on tick burdens were found among four species of passerine bird (Chapter 5). There were also different rates of decline in tick burdens among bird species in response to a long term decrease in questing tick pressure over the study. Species specific patterns may be driven by differences in behaviour and immunity and highlight the importance of comparative approaches. Combining whole genome sequencing (WGS) and population genetics approaches offers a novel approach to identify ecological drivers of pathogen populations. An initial analysis of WGS from B. burgdorferi s.s. isolates sampled 16 years apart suggests that there is a signal of measurable evolution (Chapter 6). This suggests demographic analyses may be applied to understand ecological and evolutionary processes of these bacteria. This work shows how host communities, habitat and climatic factors can affect the local transmission dynamics of B. burgdorferi s.l. and the potential risk of infection to humans. Spatial and temporal heterogeneity in pathogen dynamics poses challenges for the prediction of risk. New tools such as WGS of the pathogen (Chapter 6) and blood meal analysis techniques will add power to future studies on the ecology and evolution of B. burgdorferi s.l.

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The food of the Nile perch has changed since its introduction into Lakes Victoria, Kyoga and Nabugabo and stabilized on Caridina nilotica, Anisopteran nymphs, Rastrineobola argentea, Nile perch juveniles, and tilapiines. For the Nile perch to sustain production in these lakes, its is important that these prey species are properly managed.

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Symbiotic relationships between insects and beneficial microbes are very common in nature, especially within the Hemiptera. The brown marmorated stink bug, Halyomorpha halys Stål, harbors a symbiont, Pantoea carbekii, within the fourth region of the midgut in specialized crypts. In this dissertation, I explored this insect- microbe relationship. I determined that the brown marmorated stink bug is heavily reliant on its symbiont, and that experimental removal of the symbiont from the egg mass surface prior to nymphal acquisition led to lower survival, longer development, lower fecundity, and aberrant nymphal behavior. Additionally, I determined that even when the symbiont is acquired and housed in the midgut crypts, it is susceptible to stressors. Stink bugs reared at a higher temperature showed lower survival, longer development, and a cease in egg mass production, and when bugs were screened for their symbiont, fewer had successfully retained it while under heat stress. Finally, with the knowledge that the stink bug suffers decreases in fitness when its symbiont is missing or stressed, I wanted to determine if targeting the symbiont was a possible management technique for the stink bug. I tested the efficacy of a number of different insecticidal and antimicrobial products to determine whether prevention of symbiont acquisition from the egg mass was possible, and results indicated that transmission of the symbiont from the egg mass to the newly hatched nymph was negatively impacted when certain products were applied (namely surfactants or products containing surfactants). Additionally, direct effects on hatch rate and survival were reported for certain products, namely the insect growth regulator azadirachtin, which suggests that nymphs can pick up residues from the egg mass surface while probing for the symbiont. I conclude that P. carbekii plays a critically important role in the survival of its host, the brown marmorated stink bug, and its presence on the egg mass surface before nymphal hatch makes it targetable as a potential management technique.

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The defeat of South Vietnam in 1975 transformed Vietnamese men into fleeing refugees, boat people, and state-sponsored asylees. Writing against the popular and scholarly representations of Vietnamese refugee men as incapacitated objects of rescue, this paper provides an in-depth analysis of the intimate, insightful, and intense portrayal of Vietnamese masculinities in lê thi diem thúy’s novel, The Gangster We Are All Looking For. Focusing on the “sad and broken” father in the novel, the article conceptualizes his bouts of domestic violence neither as a private family matter nor an example of individual failing, but as a social, historical, and transnational affair that exposes the conditions—war, urban neglect, poverty—under which Vietnamese masculinity is continually produced, negotiated and transformed.

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Aphids cause significant losses in many agricultural crops and in many cases cause repeated insecticide sprays, which increase the risk of resistance. Therefore, other alternatives are needed to control them. The toxic, antireproductive, and feeding deterrent effects of a mannosebinding lectin isolated from bulbs of Phycella australis Ravenna (Amaryllidaceae), named Phycella australis agglutinin (PAA) was assayed on nymphs of the aphids Acyrthosiphon pisum Harris and Myzus persicae Sulzer fed with an artificial diet. After 72 h of PAA exposure, lethal concentration (LC50) values were 109 and 313 μg mL-1 for A. pisum and M. persicae, respectively, while LC90 values were 248 and 634 μg mL-1. Sub-lethal concentrations of PAA significantly reduced the aphid fecundity at a concentration of 80 μg mL-1. Only a total of 5.7 descendants per female were recorded for A. pisum (32% control progeny) and 12.4 for M. persicae (39% control progeny). Acyrthosiphon pisum was strongly deterred by PAA under choice conditions, as after 72 h exposed to 80 μg PAA mL-1 of diet, the feeding deterrent index was 0.91 for A. pisum and only 0.38 for M. persicae. In conclusion, the mannosebinding lectin isolated from bulbs of P. australis showed acute and chronical insecticidal activity against the pea and green peach aphids.