1,510 research outputs found

    Ostracods from freshwater and brackish environments of the Carboniferous of the Midland Valley of Scotland : the early colonization of terrestrial water bodies

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    The Mississippian Strathclyde Group of the Midland Valley of Scotland yields some of the earliest non-marine ostracods. The succession records shallow marine, deltaic, estuarine, lagoonal, lacustrine, fluvial and swamp environments representing a series of staging-posts between fully marine and limnetic settings. Macrofossils and ostracods are assigned to marine, marginal marine, brackish and freshwater environments based on their faunal assemblage patterns. Key brackish to freshwater ostracods are Geisina arcuata, Paraparchites circularis n. sp., Shemonaella ornata n. sp. and Silenites sp. A, associated with the bivalves Anthraconaia, Carbonicola, Cardiopteridium, Curvirimula, Naiadites, the microconchid ‘Spirorbis’, Spinicaudata and fish. Many Platycopina and Paraparchiticopina ostracods are interpreted as euryhaline, which corresponds with their occurrence in marine to coastal plain water bodies, and supports the ‘estuary effect’ hypothesis of non-marine colonization. The success of non-marine colonization by ostracods was dependent on the intrinsic adaptations of ostracod species to lower salinities, such as new reproductive strategies and the timing of extrinsic mechanisms to drive non-marine colonization, such as sea-level change. The genus Carbonita is the oldest and most common freshwater ostracod, and went on to dominate freshwater environments in the Late Palaeozoic

    The Holobiont Imperative: perspectives from early emerging animals

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    This book examines how the growing knowledge of the huge range of animal-bacterial interactions, whether in shared ecosystems or intimate symbioses, is fundamentally altering our understanding of animal biology. Individuals from simple invertebrates to human are not solitary, homogenous entities but consist of complex communities of many species that likely evolved during a billion years of coexistence. Defining the individual microbe-host conversations in these consortia, is a challenging but necessary step on the path to understanding the function of the associations as a whole. The hologenome theory of evolution considers the holobiont with its hologenome as a unit of selection in evolution. This new view may have profound impact on understanding a strictly microbe/symbiont-dependent life style and its evolutionary consequences. It may also affect the way how we approach complex environmental diseases from corals (coral bleaching) to human (inflammatory bowel disease etc). The book is written for scientists as well as medically interested persons in the field of immunobiology, microbiology, evolutionary biology, evolutionary medicine and corals

    Planning the asphalt construction process:Towards more consistent paving and compaction operations

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    This research addresses the challenge of linking paving and compaction given that they are mostly treated as detached activities, leading to a decrease in the quality of the compacted asphalt layer. The objective was to develop a support tool that can assist decision-making related to equipment allocation and compaction strategies to be followed, such that an asphalt layer- given the prevailing conditions at the construction site- can be compacted efficiently and uniformly within a limited time interval. A basic planning protocol was then developed based on variables such as asphalt cooling, paver characteristics, roller characteristics and road geometry. 12 road construction projects were monitored over a 3- month period. Empirical data on paver speed, roller speed and the number of roller passes served as input for the tool. The monitored projects were evaluated by calculating actual paver output and theoretical and actual roller output on an interval scale and checking whether the output rates were aligned to each other during the whole construction process. The results show that in most cases, paver output, roller output and the available time for compaction were not aligned. The theoretical concepts applied in this research and the developed support tool for decision making appear to be useful for planning and monitoring paving and compaction and for steering it towards a more uniform process. This may lead to an improvement in the quality of the final compacted asphalt layer

    Imaging atlas for eligibility and on-study safety of potential knee adverse events in anti-NGF studies (Part 1)

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    SummaryMonoclonal antibodies that bind and inhibit nerve growth factor (NGF) have demonstrated both, good analgesic efficacy and improvement in function in patients with osteoarthritis (OA). Despite initial promising data, trials in OA had been suspended by the Federal Food and Drug Administration (FDA) due to concerns over accelerated rates of OA progression. Imaging will play a crucial role in future clinical trials to define eligibility of potential participants and to monitor safety during the course of these studies. This will require baseline and frequent follow-up radiographs of both, the index joints and other large weight bearing joints to identify subjects at risk prior inclusion and on study so treatment can be discontinued.This imaging overview in the form of an atlas describes and illustrates potential exclusionary joint imaging findings at eligibility and potential adverse joint events on radiography and magnetic resonance imaging (MRI) in studies investigating a-NGF compounds. The overarching goal of this atlas is to facilitate trial design and to promote a common language and understanding between potential expert readers. This first section of the atlas will focus on knee joint specific findings that are relevant to a-NGF studies

    Supersymmetric particle mass measurement with invariant mass correlations

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    The kinematic end-point technique for measuring the masses of supersymmetric particles in R-Parity conserving models at hadron colliders is re-examined with a focus on exploiting additional constraints arising from correlations in invariant mass observables. The use of such correlations is shown to potentially resolve the ambiguity in the interpretation of quark+lepton end-points and enable discrimination between sequential two-body and three-body lepton-producing decays. The use of these techniques is shown to improve the SUSY particle mass measurement precision for the SPS1a benchmark model by at least 20-30% compared to the conventional end-point technique.Comment: 29 pages, 23 .eps figures, JHEP3 style; v2 adds some references and small clarifications to text; v3 adds some more clarifications to the tex

    Mass Determination in SUSY-like Events with Missing Energy

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    We describe a kinematic method which is capable of determining the overall mass scale in SUSY-like events at a hadron collider with two missing (dark matter) particles. We focus on the kinematic topology in which a pair of identical particles is produced with each decaying to two leptons and an invisible particle (schematically, pp→YY+jetspp\to YY+jets followed by each YY decaying via Y→ℓX→ℓℓ′NY\to \ell X\to \ell\ell'N where NN is invisible). This topology arises in many SUSY processes such as squark and gluino production and decay, not to mention t\anti t di-lepton decays. In the example where the final state leptons are all muons, our errors on the masses of the particles YY, XX and NN in the decay chain range from 4 GeV for 2000 events after cuts to 13 GeV for 400 events after cuts. Errors for mass differences are much smaller. Our ability to determine masses comes from considering all the kinematic information in the event, including the missing momentum, in conjunction with the quadratic constraints that arise from the YY, XX and NN mass-shell conditions. Realistic missing momentum and lepton momenta uncertainties are included in the analysis.Comment: 41 pages, 14 figures, various clarifications and expanded discussion included in revised version that conforms to the version to be publishe

    A quark model analysis of the charge symmetry breaking in nuclear force

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    In order to investigate the charge symmetry breaking (CSB) in the short range part of the nuclear force, we calculate the difference of the masses of the neutron and the proton, ΔM\Delta {\rm M}, the difference of the scattering lengths of the p-p and n-n scatterings, Δa\Delta a, and the difference of the analyzing power of the proton and the neutron in the n-p scattering, ΔA(θ)\Delta A(\theta), by a quark model. In the present model the sources of CSB are the mass difference of the up and down quarks and the electromagnetic interaction. We investigate how much each of them contributes to ΔM\Delta {\rm M}, Δa\Delta a and ΔA(θ)\Delta A(\theta). It is found that the contribution of CSB of the short range part in the nuclear force is large enough to explain the observed ΔA(θ)\Delta A(\theta), while Δa\Delta a is rather underestimated.Comment: 26 pages,6 figure

    History of Psychology

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    Openly licensed anthology focused on the theme of the History of Psychology. Contains: The Mind and the Brain by Alfred Binet; Dream Psychology: Psychoanalysis for Beginners by Sigmund Freud; The Principles of Psychology, Volume 1 (of 2) by William James; The Principles of Psychology, Volume 2 (of 2) by William James; Collected Papers on Analytical Psychology by C. G. Jung; Memoirs of Extraordinary Popular Delusions and the Madness of Crowds by Charles Mackay; The Psychology of Arithmetic by Edward L. Thorndike

    Discovery and Measurement of Sleptons, Binos, and Winos with a Z'

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    Extensions of the MSSM could significantly alter its phenomenology at the LHC. We study the case in which the MSSM is extended by an additional U(1) gauge symmetry, which is spontaneously broken at a few TeV. The production cross-section of sleptons is enhanced over that of the MSSM by the process pp→Z′→ℓ~ℓ~∗pp\to Z' \to \tilde{\ell} \tilde{\ell}^*, so the discovery potential for sleptons is greatly increased. The flavor and charge information in the resulting decay, ℓ~→ℓ+LSP\tilde{\ell} \to \ell + {LSP}, provides a useful handle on the identity of the LSP. With the help of the additional kinematical constraint of an on-shell Z', we implement a novel method to measure all of the superpartner masses involved in this channel. For certain final states with two invisible particles, one can construct kinematic observables bounded above by parent particle masses. We demonstrate how output from one such observable, m_T2, can become input to a second, increasing the number of measurements one can make with a single decay chain. The method presented here represents a new class of observables which could have a much wider range of applicability.Comment: 20 pages, 15 figures; v2 references added and minor change
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