11 resultados para EDAPHIC MITE

em Queensland University of Technology - ePrints Archive


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Hitherto, the Malaconothridae contained Malaconothrus Berlese, 1904 and Trimalaconothrus Berlese, 1916, defined by the possession of one pre-tarsal claw (monodactyly) or by three claws (tridactyly) respectively. However, monodactyly is a convergent apomorphy within the Oribatida and an unreliable character for a classification. Therefore we undertook a phylogenetic analysis of 102 species as the basis for a taxonomic review of the Malaconothridae. We identified two major clades, equivalent to the genera Tyrphonothrus Knülle, 1957 and Malaconothrus. These genera are redefined. Trimala-conothrus becomes the junior subjective synonym of Malaconothrus. Some 42 species of Trimalaconothrus are recom-bined to Malaconothrus and 15 species to Tyrphonothrus. Homonyms created by the recombinations are rectified. The replacement name M. hammerae nom. nov. is proposed for M. angulatus Hammer, 1958, the junior homonym of M. an-gulatus (Willmann, 1931) and the replacement name M. luxtoni nom. nov. is proposed for M. scutatus Luxton, 1987, the junior homonym of M. scutatus Mihelč ič, 1959. Trimalaconothrus iteratus Subías, 2004 is an unnecessary replacement name and is a junior objective synonym of Malaconothrus longirostrum (Hammer 1966). Malaconothrus praeoccupatus Subías, 2004 is a junior objective synonym of M. machadoi Balogh & Mahunka, 1969. Malaconothrus obsessus (Subías, 2004), an unnecessary replacement name for Trimalaconothrus albulus Hammer 1966 sensu Tseng 1982, becomes an available name for what is in fact a previously-undescribed species of Malaconothrus. We describe four new species of Tyrphonothrus: T. gnammaensis sp. nov. from Western Australia, T. gringai sp. nov. and T. maritimus sp. nov. from New South Wales, and T. taylori sp. nov. from Queensland. We describe six new species of Malaconothrus: M. beecroftensis sp. nov., M. darwini sp. nov. M. gundungurra sp. nov. and M. knuellei sp. nov. from New South Wales, M. jowettae sp. nov. from Norfolk Island, and M. talaitae sp. nov. from Victoria.

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The genus Austronothrus was previously known from three species recorded only from New Zealand. Austronothrus kinabalu sp. nov. is described from Sabah, Borneo and A. rostralis sp. nov. from Norfolk Island, south-west Pacific. A key to Austronothrus is included. These new species extend the distribution of Austronothrus beyond New Zealand and confirms that the subfamily Crotoniinae is not confined to former Gondwanan landmasses. The distribution pattern of Austronothrus spp., combining Oriental and Gondwanan localities, is indicative of a curved, linear track; consistent with the accretion of island arcs and volcanic terranes around the plate margins of the Pacific Ocean, with older taxa persisting on younger island though localised dispersal within island arc metapopulations. Phylogenetic analysis and an area cladogram are consistent with a broad ancestral distribution of Austronothrus in the Oriental region and on Gondwanan terranes, with subsequent divergence and distribution southward from the Sunda region to New Zealand. This pattern is more complex than might be expected if the New Zealand oribatid fauna was derived from dispersal following re-emergence of land after inundation during the Oligocene (25 mya), as well as if the fauna emanated from endemic, relictual taxa following separation of New Zealand from Gondwana during the Cretaceous (80 mya).

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This project expands upon the discovery that scabies mites produce protein molecules that interfere with the human complement cascade, disrupting a critical component of the early stages of the host immune response. This is believed to provide an optimal environment for the development of commonly associated secondary bacterial infections. The thesis investigated the effect of two distinct scabies mite proteins, namely SMS B4 and SMIPP-S I1, on the in vitro proliferation of Group A Streptococcus in whole human blood. Additionally, in vitro immunoassays were performed to determine if complement mediated opsonisation and phagocytosis were also disrupted.

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Introduction Novel ecosystems that contain new combinations of invasive alien plants (IAPs) present a challenge for managers. Yet, control strategies that focus on the removal of the invasive species and/or restoring historical disturbance regimes often do not provide the best outcome for long-term control of IAPs and the promotion of more desirable plant species. Methods This study seeks to identify the primary drivers of grassland invasion to then inform management practices toward the restoration of native ecosystems. By revisiting both published and unpublished data from experiments and case studies within mainly an Australian context for native grassland management, we show how alternative states models can help to design control strategies to manage undesirable IAPs by manipulating grazing pressure. Results Ungulate grazing is generally considered antithetical to invasive species management because in many countries where livestock production is a relatively new disturbance to grasslands (such as in Australia and New Zealand as well as Canada and the USA), selective grazing pressure may have facilitated opportunities for IAPs to establish. We find that grazing stock can be used to manipulate species composition in favour of the desirable components in pastures, but whether grazing is rested or strategically applied depends on the management goal, sizes of populations of the IAP and more desirable species, and climatic and edaphic conditions. Conclusions Based on our findings, we integrated these relationships to develop a testable framework for managing IAPs with strategic grazing that considers both the current state of the plant community and the desired future state—i.e. the application of the principles behind reclamation, rehabilitation, restoration or all three—over time.

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Scrub typhus is a vector-borne disease carried by the chigger mite. The aetiological agent is the rickettsia Orientia tsutsugamushi, which is endemic to several countries in the Asia-Pacific region, including China [1]. It is also a travel-associated disease [2] and of great importance among military personnel [3], [4]. During the Second World War, scrub typhus was associated with a higher case fatality ratio than any other infectious disease in the China-Burma-India theatre of operations 1,3. Clinical presentation in patients varies from asymptomatic to life-threatening disease [5], including acute hearing loss and multiple organ failure [6], [7]. To date, there is still no effective and reliable human vaccine against scrub typhus and no point-of-care diagnostics available [1].

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We investigated the ectoparasitic mite loads (Macronyssus: Macronyssidae: Acarina) on 2 species of flat-headed bats, Tylonycteris pachypus and T. robustula (Mammalia: Chiroptera: Vespertilionidae) in 2 counties of Guangxi Province, southern China, from 2002 to 2005. In Longzhou County both species of bat occur sympatrically, but only T. pachypus occurs in Ningming County. Individuals of the smaller species (T. pachypus) harbored significantly more mites than did those of T. robustula. In both species males harbored more mites than nonreproductive females, pregnant females had more mites than lactating and nonreproductive females, and juveniles harbored more mites than adults. Mite load on both species of bats showed significant seasonal variation, declining from spring to winter. No correlation was found between mite load and size of the host colony. We discuss our findings in relation to the ecology and biology of both hosts and parasites.

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Humans dominate many important Earth system processes including the nitrogen (N) cycle. Atmospheric N deposition affects fundamental processes such as carbon cycling, climate regulation, and biodiversity, and could result in changes to fundamental Earth system processes such as primary production. Both modelling and experimentation have suggested a role for anthropogenically altered N deposition in increasing productivity, nevertheless, current understanding of the relative strength of N deposition with respect to other controls on production such as edaphic conditions and climate is limited. Here we use an international multiscale data set to show that atmospheric N deposition is positively correlated to aboveground net primary production (ANPP) observed at the 1-m2 level across a wide range of herbaceous ecosystems. N deposition was a better predictor than climatic drivers and local soil conditions, explaining 16% of observed variation in ANPP globally with an increase of 1 kg N·ha-1·yr-1 increasing ANPP by 3%. Soil pH explained 8% of observed variation in ANPP while climatic drivers showed no significant relationship. Our results illustrate that the incorporation of global N deposition patterns in Earth system models are likely to substantially improve estimates of primary production in herbaceous systems. In herbaceous systems across the world, humans appear to be partially driving local ANPP through impacts on the N cycle.

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Phage display is an advanced technology that can be used to characterize the interactions of antibody with antigen at the molecular level. It provides valuable data when applied to the investigation of IgE interaction with allergens. The aim of this rostrum article is to provide an explanation of the potential of phage display for increasing the understanding of allergen- IgE interaction, the discovery of diagnostic reagents, and the development of novel therapeutics for the treatment of allergic disease. The significance of initial studies that have applied phage display technology in allergy research will be highlighted. Phage display has been used to clone human IgE to timothy grass pollen allergen Phl p 5, to characterize the epitopes for murine and human antibodies to a birch pollen allergen Bet v 1, and to elucidate the epitopes of a murine mAb to the house dust mite allergen Der p 1. The technology has identified peptides that functionally mimic sites of human IgE constant domains and that were used to raise antiserum for blocking binding of IgE to the FcεRI on basophils and subsequent release of histamine. Phage display has also been used to characterize novel peanut and fungal allergens. The method has been used to increase our understanding of the molecular basis of allergen-IgE interactions and to develop clinically relevant reagents with the pharmacologic potential to block the effector phase of allergic reactions. Many advances from these early studies are likely as phage display technology evolves and allergists gain expertise in its research applications.