112 research outputs found

    Syncope in the elderly: An update

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    Abstract Syncope in the elderly is an extremely prevalent clinical condition characterized by high mortality and presence of recurrences. The diagnosis of syncope in the elderly is sometimes difficult and multidimensional geriatric assessment should be carefully administered. Diagnostic algorithms should be applied with attention, although unknown syncope is still frequent. The therapeutic approach to syncope in the elderly is complicated by the high prevalence of neurally-mediated syncope, in which the therapeutic approach is still unknown. The establishment of a "Syncope Unit" has certainly improved the diagnostic-therapeutic approach to patients with syncope, especially in old age where the management is extremely difficult

    Role of supplemental foods and habitat structural complexity in persistence and coexistence of generalist predatory mites

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    Variation in the strength of intraguild predation (IGP) may be related to habitat structural complexity and to additional resources outside the narrow predator-prey relationship. We studied the food web interactions on grape, which involves two generalist predatory mites. We evaluated the effects of grape powdery mildew (GPM) as supplemental food, and habitat structural complexity provided by domatia. Our findings suggest that structural and nutritional diversity/complexity promote predatory mite abundance and can help to maintain the beneficial mites - plants association. The effect of these factors on coexistence between predators is influenced by the supplemental food quality and relative differences in body size of interacting species

    Old lineage on an old island : Pixibinthus, a new cricket genus endemic to New Caledonia shed light on gryllid diversification in a hotspot of biodiversity

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    Few studies have focused on the early colonization of New Caledonia by insects, after the re-emergence of the main island, 37 Myr ago. Here we investigate the mode and tempo of evolution of a new endemic cricket genus, Pixibinthus, recently discovered in southern New Caledonia. First we formally describe this new monotypic genus found exclusively in the open shrubby vegetation on metalliferous soils, named 'maquis minier', unique to New Caledonia. We then reconstruct a dated molecular phylogeny based on five mitochondrial and four nuclear loci in order to establish relationships of Pixibinthus within Eneopterinae crickets. Pixibinthus is recovered as thesister clade of the endemic genus Agnotecous, mostly rainforest-dwellers. Dating results show that the island colonization by their common ancestor occurred around 34.7 Myr, shortly after New Caledonia re-emergence. Pixibinthus and Agnotecous are then one of the oldest insect lineages documented so far for New Caledonia. This discovery highlights for the first time two clear-cut ecological specializations between sister clades, as Agnotecous is mainly found in rainforests with 19 species, whereas Pixibinthus is found in open habitats with a single documented species. The preference of Pixibinthus for open habitats and of Agnotecous for forest habitats nicely fits an acoustic specialization, either explained by differences in body size or in acoustic properties of their respective habitats. We hypothesize that landscape dynamics, linked to major past climatic events and recent change in fire regimes are possible causes for both present-day low diversity and rarity in genus Pixibinthus. The unique evolutionary history of this old New Caledonian lineage stresses the importance to increase our knowledge on the faunal biodiversity of 'maquis minier', in order to better understand the origin and past dynamics of New Caledonian biota

    Influence of water availability on native wildflower phenology and pollinator attractiveness

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    In 2017 and 2018, we performed a field study screening 23 garden-friendly, native Willamette Valley wildflowers (and four exotic comparators) for their attractiveness to pollinators. Flower phenology and pollinator visitation differed between the two seasons. There was a marked difference in both flowering timing and duration. The 2017 peak bloom began an average of 17.7 days later than 2018, and ceased 27.7 days later. Thus, the length of 2018 peak bloom was 10 days shorter on average, and ended a month earlier. We hypothesize that these differences are due to water availability. In 2017, we irrigated to ensure perennial establishment, while in 2018 we did not irrigate. Furthermore, in 2017 the region received 2.83 inches of rain across May-August, whereas in 2018 there was only 0.87 inches of rain in May-August. This may have accelerated flowering and attenuated its length. These phenological differences may have implications for the abundance and species-richness of attracted pollinators. In 2018, flowers opened earlier and for a shorter duration on average. However, across our timed pollinator counts we observed more native bee visitors per observation. When considering native bees, Gilia capitata, Madia elegans, Aster subspicatus, Eschscholzia californica, and Solidago canadensis attracted the greatest bee abundance in 2017. In 2018, Eschscholzia californica, Aster subspicatus, Phacelia heterophylla, Solidago canadensis, and Clarkia amoena were the most attractive to native bees. During our 2019 field season we will irrigate half the plots, to address both temporal variation and the impact of irrigation on bloom phenology and attractiveness

    Gardener Perceptions of Native Pollinator Plants

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    Native plantings are used in urban areas to improve pollinator habitat. To achieve wide adoption, these plant choices must be attractive to home gardeners as well as to pollinators. We distributed two surveys to identify native Willamette Valley pollinator plants that are aesthetically pleasing to home gardeners. The first survey sought to ascertain baseline attractiveness, and asked gardeners to rank the attractiveness of 23 wildflowers on a 1-5 Likert scale. In second survey, we were interested in how sharing information on the benefits of these plants impacts perceived attractiveness. We asked gardeners to rate the attractiveness of a subset of 11 of these 23 wildflowers both before, and after, being shared information on each flower’s attractiveness to bees. Both surveys also included space for open-ended comments. We found a high level of acceptance of native wildflowers by gardeners (over half had mean attractiveness scores of 4.0 or above), and gardeners found native plants significantly more attractive after learning about the bees that visit each plant. Gardeners who identified as “native plant gardeners” found all of the study plants significantly more attractive than non-“native plant gardeners”. In the open-ended comments, gardeners stated that they were most negatively concerned with the aesthetics and aggressive growth of flowers. Gardeners felt positively about flower aesthetics and beneficial ecological traits (e.g. pollinator attractiveness, drought tolerance). We identify five species of native wildflowers that Pacific Northwest nurseries might consider marketing as pollinator plants (Gilia capitata, Clarkia amoena, Eschscholzia californica, Madia elegans, and Sidalcea asprella ssp. virgata)
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