4,882 research outputs found

    A first order Tsallis theory

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    We investigate first-order approximations to both i) Tsallis' entropy SqS_q and ii) the SqS_q-MaxEnt solution (called q-exponential functions eqe_q). It is shown that the functions arising from the procedure ii) are the MaxEnt solutions to the entropy emerging from i). The present treatment is free of the poles that, for classic quadratic Hamiltonians, appear in Tsallis' approach, as demonstrated in [Europhysics Letters {\bf 104}, (2013), 60003]. Additionally, we show that our treatment is compatible with extant date on the ozone layer.Comment: 4 figures adde

    Using adult mosquitoes to transfer insecticides to Aedes aegypti larval habitats.

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    Vector control is a key means of combating mosquito-borne diseases and the only tool available for tackling the transmission of dengue, a disease for which no vaccine, prophylaxis, or therapeutant currently exists. The most effective mosquito control methods include a variety of insecticidal tools that target adults or juveniles. Their successful implementation depends on impacting the largest proportion of the vector population possible. We demonstrate a control strategy that dramatically improves the efficiency with which high coverage of aquatic mosquito habitats can be achieved. The method exploits adult mosquitoes as vehicles of insecticide transfer by harnessing their fundamental behaviors to disseminate a juvenile hormone analogue (JHA) between resting and oviposition sites. A series of field trials undertaken in an Amazon city (Iquitos, Peru) showed that the placement of JHA dissemination stations in just 3-5% of the available resting area resulted in almost complete coverage of sentinel aquatic habitats. More than control mortality occurred in 95-100% of the larval cohorts of Aedes aegypti developing at those sites. Overall reductions in adult emergence of 42-98% were achieved during the trials. A deterministic simulation model predicts amplifications in coverage consistent with our observations and highlights the importance of the residual activity of the insecticide for this technique

    QUANTITATIVE ANALYSIS OF REPAIRED AND UNREPAIRED DAMAGE TO TRILOBITES FROM THE CAMBRIAN (STAGE 4, DRUMIAN) IBERIAN CHAINS, NE SPAIN

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    Repaired fossil skeletons provide the opportunity to study predation rates, repair mechanisms, and ecological interactions in deep time. Trilobites allow the study of repaired damage over long time periods and large geographic areas due to their longevity as a group, global distribution, and well-preserved mineralized exoskeletons. Repair frequencies on trilobites from three sites representing offshore marine environments in the Iberian Chains (Spain) show no injuries on 45 complete redlichiid thoraces from Minas Tierga (Huérmeda Formation, Cambrian Series 2, Stage 4), or 23 complete Eccaparadoxides pradoanus thoraces from Mesones de Isuela (Murero Formation, Cambrian Series 3, Drumian). Ten injuries on 69 E. pradoanus thoraces from Purujosa (Murero Formation, Cambrian Series 3, Drumian) were noted. There is no evidence for laterally asymmetric predation or size selection on the trilobites in this study. Weak evidence for selection for the rear of the thorax is documented. A series of injured trilobites illustrates four stages of the healing process. Analysis of injury locations and frequency suggests that injuries to these trilobites are predatory in origin. Semilandmark analysis of previously described exoskeletons with unrepaired damage assigned to the ichnotaxon Bicrescomanducator serratus alongside newly collected damaged exoskeletons from Purujosa (Mansilla and Murero Formations, Stage 5, Drumian), Mesones de Isuela (Murero Formation, Drumian), and Minas Tierga (Huérmeda Formation, Stage 4) found that shapes of biotic and abiotic breaks could not be distinguished.Department of Zoology, University of Oxford, Reino UnidoInstitute of Earth Sciences, University of Lausanne, SuizaPaleoscience Research Centre School of Environmental and Rural Science, University of New England, AustraliaUnidad de Zaragoza, Instituto Geológico y Minero de España, EspañaUnidad Asociada en Ciencias de la Tierra, Universidad de Zaragoza, Españ
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