780 research outputs found

    State of the Birds in Exurbia

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    Low density rural sprawl, or exurban development, results in significant negative impacts on wildlife including birds. We describe the results of a decade of field studies to document the response of birds and other taxa to exurban development in the Park. We have investigated: the size of the ecological impact zone associated with exurban houses and roads in the Adirondacks, the characteristics of avian communities before and after residential construction, whether exurban development alters the health of individual birds, whether the ecological context of the development regulates the intensity of its impacts, and how individual land ethics and land use decisions, operating with a regional land use context, shape human impacts on biological communities. We briefly describe these studies and draw conclusions across them to provide insight into the state of the birds in the exurban Adirondacks. Broadly, we find that: the size of the impact resulting from exurban development can exceed its physical footprint significantly, changes in avian communities associated with exurban development do not appear to be driven solely by the associated road network, these changes can be very rapid and are consistent across some taxa and ecosystems, predation pressure may be a key mechanism, the attraction effect of exurban development may be stronger than the deterrent effect, and the most prevalent pattern of change is one of simplification of avian communities. Neotropical migrants may be a particularly sensitive group in the Adirondacks

    Endothelin-1, phorbol esters and phenylephrine stimulate MAP kinase activities in ventricular cardiomyocytes

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    AbstractET-1 stimulated MBP kinase activity in cultured cardiomyocytes. Maximal activation (3.5-fold) was at 5 min. EC50 was 0.2 nM. PMA or PE also increased MBP kinase (4- or 2.5-fold, respectively). Pre-treatment with PMA down-regulated the subsequent response to ET-1 or PMA. ET-1- or PMA-stimulated MBP kinase was resolved into 2 major (peaks II and IV) and 2 minor peaks by FPLC on Mono Q. Peaks II and IV were inactivated by either LAR or PP2A. Renatured MBP kinase activities following SDS-PAGE in MBP-containing gels and immunoblot analysis showed that peak II was a p42 MAP kinase and peak IV was a p44 MAP kinase

    Scalar dark matter vortex stabilization with black holes

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    Galaxies and their dark-matter halos are commonly presupposed to spin. But it is an open question how this spin manifests in halos and soliton cores made of scalar dark matter (SDM, including fuzzy/wave/ultralight-axion dark matter). One way spin could manifest in a necessarily irrotational SDM velocity field is with a vortex. But recent results have cast doubt on this scenario, finding that vortices are generally unstable except with substantial repulsive self-interaction. In this paper, we introduce an alternative route to stability: in both (non-relativistic) analytic calculations and simulations, a black hole or other central mass at least as massive as a soliton can stabilize a vortex within it. This conclusion may also apply to AU-scale halos bound to the sun and stellar-mass-scale Bose stars.Comment: Accepted by JCAP. 22 pages, 5 figures. Supplementary animations at https://doi.org/10.5281/zenodo.7675830 or https://www.youtube.com/playlist?list=PLHrf0iQS5SY7Xt2sjqskF3kmHd00Hrdf

    Anopheles stephensi p38 MAPK signaling regulates innate immunity and bioenergetics during Plasmodium falciparum infection.

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    BackgroundFruit flies and mammals protect themselves against infection by mounting immune and metabolic responses that must be balanced against the metabolic needs of the pathogens. In this context, p38 mitogen-activated protein kinase (MAPK)-dependent signaling is critical to regulating both innate immunity and metabolism during infection. Accordingly, we asked to what extent the Asian malaria mosquito Anopheles stephensi utilizes p38 MAPK signaling during infection with the human malaria parasite Plasmodium falciparum.MethodsA. stephensi p38 MAPK (AsP38 MAPK) was identified and patterns of signaling in vitro and in vivo (midgut) were analyzed using phospho-specific antibodies and small molecule inhibitors. Functional effects of AsP38 MAPK inhibition were assessed using P. falciparum infection, quantitative real-time PCR, assays for reactive oxygen species and survivorship under oxidative stress, proteomics, and biochemical analyses.ResultsThe genome of A. stephensi encodes a single p38 MAPK that is activated in the midgut in response to parasite infection. Inhibition of AsP38 MAPK signaling significantly reduced P. falciparum sporogonic development. This phenotype was associated with AsP38 MAPK regulation of mitochondrial physiology and stress responses in the midgut epithelium, a tissue critical for parasite development. Specifically, inhibition of AsP38 MAPK resulted in reduction in mosquito protein synthesis machinery, a shift in glucose metabolism, reduced mitochondrial metabolism, enhanced production of mitochondrial reactive oxygen species, induction of an array of anti-parasite effector genes, and decreased resistance to oxidative stress-mediated damage. Hence, P. falciparum-induced activation of AsP38 MAPK in the midgut facilitates parasite infection through a combination of reduced anti-parasite immune defenses and enhanced host protein synthesis and bioenergetics to minimize the impact of infection on the host and to maximize parasite survival, and ultimately, transmission.ConclusionsThese observations suggest that, as in mammals, innate immunity and mitochondrial responses are integrated in mosquitoes and that AsP38 MAPK-dependent signaling facilitates mosquito survival during parasite infection, a fact that may attest to the relatively longer evolutionary relationship of these parasites with their invertebrate compared to their vertebrate hosts. On a practical level, improved understanding of the balances and trade-offs between resistance and metabolism could be leveraged to generate fit, resistant mosquitoes for malaria control

    Tiered trees, weights, and q-Eulerian numbers

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    Maxmin trees are labeled trees with the property that each vertex is either a local maximum or a local minimum. Such trees were originally introduced by Postnikov [12], who gave a formula to count them and different combinatorial interpretations for their number. In this paper we generalize this construction and define tiered trees by allowing more than two classes of vertices. Tiered trees arise naturally when counting the absolutely indecomposable representations of certain quivers, and also when one enumerates torus orbits on certain homogeneous varieties. We define a notion of weight for tiered trees and prove bijections between various weight 0 tiered trees and other combinatorial objects; in particular order n weight 0 maxmin trees are naturally in bijection with permutations on n−1 letters. We conclude by using our weight function to define a new q-analogue of the Eulerian numbers

    A portable centrifugal analyser for liver function screening

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    Mortality rates of up to 50% have been reported after liver failure due to drug-induced hepatotoxicity and certain viral infections(Gao et al. 2008). These adverse conditions frequently affect HIV and tuberculosis patients on regular medication in resource-poor settings. Here, we report full integration of sample preparation with read-out of a 5-parameter liver assay panel (LAP) on a portable, easy-to-use, fast and cost- efficient centrifugal microfluidic analysis system (CMAS). Our unique, dissolvable-film based centrifugo- pneumatic valving was employed to provide sample-to-answer fashion automation for plasma extraction (from finger-prick of blood), metering and aliquoting into separate reaction chambers for parallelized colorimetric quantification during rotation. The entire LAP completes in less than 20 minutes while using only a tenth the reagent volumes when compared with standard hospital laboratory tests. Accuracy of in-situ liver function screening was validated by 96 separate tests with an average coefficient of variance (CV) of 7.9% compared to benchtop and hospital lab tests. Unpaired two sample statistical t-tests were used to compare the means of CMAS and benchtop reader, on one hand; and CMAS and hospital tests on the other. The results demonstrate no statistical difference between the respective means with 94% and 92% certainty of equivalence, respectively. The portable platform thus saves significant time, labour and costs compared to established technologies, and therefore comply with typical restrictions on lab infrastructure, maintenance, operator skill and costs prevalent in many field clinics of the developing world. It has been successfully deployed in a centralised lab in Nigeria

    Telecommunications. He received a BSc in Aerospace

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    2010, he was a Principal Engineer (Algorithms) at SigNav Pty Ltd where he worked for 15 years on GPS embedded firmware and algorithm development. He also worked at Auspace Ltd for 3 years as a Software Systems Engineer
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