567 research outputs found

    Assessing what is needed to resolve a molecular phylogeny: simulations and empirical data from emydid turtles

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    <p>Abstract</p> <p>Background</p> <p>Phylogenies often contain both well-supported and poorly supported nodes. Determining how much additional data might be required to eventually recover most or all nodes with high support is an important pragmatic goal, and simulations have been used to examine this question. Most simulations have been based on few empirical loci, and suggest that well supported phylogenies can be determined with a very modest amount of data. Here we report the results of an empirical phylogenetic analysis of all 10 genera and 25 of 48 species of the new world pond turtles (family Emydidae) based on one mitochondrial (1070 base pairs) and seven nuclear loci (5961 base pairs), and a more biologically realistic simulation analysis incorporating variation among gene trees, aimed at determining how much more data might be necessary to recover weakly-supported nodes with strong support.</p> <p>Results</p> <p>Our mitochondrial-based phylogeny was well resolved, and congruent with some previous mitochondrial results. For example, all genera, and all species except <it>Pseudemys concinna</it>, <it>P. peninsularis</it>, and <it>Terrapene carolina </it>were monophyletic with strong support from at least one analytical method. The Emydinae was recovered as monophyletic, but the Deirochelyinae was not. Based on nuclear data, all genera were monophyletic with strong support except <it>Trachemys</it>, and all species except <it>Graptemys pseudogeographica</it>, <it>P. concinna</it>, <it>T. carolina</it>, and <it>T. coahuila </it>were monophyletic, generally with strong support. However, the branches subtending most genera were relatively short, and intergeneric relationships within subfamilies were mostly unsupported.</p> <p>Our simulations showed that relatively high bootstrap support values (i.e. ≥ 70) for all nodes were reached in all datasets, but an increase in data did not necessarily equate to an increase in support values. However, simulations based on a single empirical locus reached higher overall levels of support with less data than did the simulations that were based on all seven empirical nuclear loci, and symmetric tree distances were much lower for single versus multiple gene simulation analyses.</p> <p>Conclusion</p> <p>Our empirical results provide new insights into the phylogenetics of the Emydidae, but the short branches recovered deep in the tree also indicate the need for additional work on this clade to recover all intergeneric relationships with confidence and to delimit species for some problematic groups. Our simulation results suggest that moderate (in the few-to-tens of kb range) amounts of data are necessary to recover most emydid relationships with high support values. They also suggest that previous simulations that do not incorporate among-gene tree topological variance probably underestimate the amount of data needed to recover well supported phylogenies.</p

    Economic evaluation strategies in telehealth: obtaining a more holistic valuation of telehealth interventions

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    Telehealth is an emerging area of medical research. Its translation from conception, to research and into practice requires tailored research and economic evaluation methods. Due to their nature telehealth interventions exhibit a number of extra-clinical benefits that are relevant when valuing their costs and outcomes. By incorporating methods to measure societal values such as patient preference and willingness-to-pay, a more holistic value can be placed on the extra-clinical outcomes associated with telehealth and evaluations can represent new interventions more effectively. Cost-benefit analysis is a method by which relevant costs and outcomes in telehealth can be succinctly valued and compared. When health economic methods are conducted using holistic approaches such as cost-benefit analysis they can facilitate the translation of telehealth research into policy and practice

    Exploring the interplay between Buddhism and career development : a study of highly skilled women workers in Sri Lanka

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    This article adopts a socio cultural lens to examine the role of Buddhism in highly skilled women workers’ careers in Sri Lanka. While Buddhism enabled women’s career development by giving them strength to cope with difficult situations in work, it also seemed to restrict their agency and constrain their career advancement. Based on our findings, we argue that being perceived as a good Buddhist woman worked as a powerful form of career capital for the respondents in our sample, who used their faith to combat gender disadvantage in their work settings

    Proton acceleration by irradiation of isolated spheres with an intense laser pulse

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    We report on experiments irradiating isolated plastic spheres with a peak laser intensity of 2-3 x 10(20) W cm(-2). With a laser focal spot size of 10 mu m full width half maximum (FWHM) the sphere diameter was varied between 520 nm and 19.3 mu m. Maximum proton energies of similar to 25 MeV are achieved for targets matching the focal spot size of 10 mu m in diameter or being slightly smaller. For smaller spheres the kinetic energy distributions of protons become nonmonotonic, indicating a change in the accelerating mechanism from ambipolar expansion towards a regime dominated by effects caused by Coulomb repulsion of ions. The energy conversion efficiency from laser energy to proton kinetic energy is optimized when the target diameter matches the laser focal spot size with efficiencies reaching the percent level. The change of proton acceleration efficiency with target size can be attributed to the reduced cross-sectional overlap of subfocus targets with the laser. Reported experimental observations are in line with 3D3V particle in cell simulations. They make use of well-defined targets and point out pathways for future applications and experiments.DFG via the Cluster of Excellence Munich-Centre for Advanced Photonics (MAP) Transregio SFB TR18NNSA DE-NA0002008Super-MUC pr48meIvo CermakCGC Instruments in design and realization of the Paul trap systemIMPRS-APSLMUexcellent Junior Research FundDAAD|ToIFEEuropean Union's Horizon research and innovation programme 633053Physic

    Mesoproterozoic surface oxygenation accompanied major sedimentary manganese deposition at 1.4 and 1.1 Ga

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    This research was funded by the Australian Science and Industry Endowment Fund (SIEF) as part of The Distal Footprints of Giant Ore Systems: UNCOVER Australia Project (RP04-063)—Capricorn Distal Footprints. EAS also thanks the donors of The American Chemical Society Petroleum Research Fund for partial support of this research (61017-ND2).Peer reviewedPublisher PD

    Towards an EU Charter of the Fundamental Rights of Nature

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    This Study aims to set a framework for the legal recognition of the Rights of Nature in the EU legal order, as a prerequisite for a different and improved relationship between human beings and Nature. This aim should be possibly accomplished through the development of a EU Charter on Fundamental Rights of Nature. Initially, the Study shows the role of Rights of Nature with respect to environmental protection goals and addresses the reasons why current EU Environmental Law is failing to deliver the required level of nature protection (Section 2). Subsequently, the Study assesses how the "Rights of Nature" may help to overcome the failures of environmental law. To this end, four paradigmatic cases are proposed and analysed (Section 3). Based on the findings of this analysis, the strategic milestones required to achieve genuine ecosystem protection are identified and presented (Section 4). Finally, the possibility of introducing a Charter of the Rights of Nature in the EU legal system, with its basic principles, recommendable features and proposed pathway is discussed (Sections 5, 6 and 7)
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