166 research outputs found

    Softly safely spoken: Role playing for Session Types

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    Session types have made much progress at permitting programs be statically verified concordant with a specified protocol. However, it is difficult to build abstractions of, or encapsulate Session types, thus limiting their flexibility. Global session types add further constraints to communication, by permitting the order of exchanges amongst many participants to be specified. The cost is that the number of participants is statically fixed. We introduce Roles in which, similarly to global session types, the number of roles and the conversations involving roles are statically known, but participants can dynamically join and leave roles and the number of participants within a role is not statically known. Statically defined roles which conform to a specified conversation can be dynamically instantiated, participants can be members of multiple roles simultaneously and can participate in multiple conversations concurrently

    Capture on High Curvature Region: Aggregation of Colloidal Particle Bound to Giant Phospholipid Vesicles

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    A very recent observation on the membrane mediated attraction and ordered aggregation of colloidal particles bound to giant phospholipid vesicles (I. Koltover, J. O. R\"{a}dler, C. R. Safinya, Phys. Rev. Lett. {\bf 82}, 1991(1999)) is investigated theoretically within the frame of Helfrich curvature elasticity theory of lipid bilayer fluid membrane. Since the concave or waist regions of the vesicle possess the highest local bending energy density, the aggregation of colloidal beads on these places can reduce the elastic energy in maximum. Our calculation shows that a bead in the concave region lowers its energy ∌20kBT\sim 20 k_B T. For an axisymmetrical dumbbell vesicle, the local curvature energy density along the waist is equally of maximum, the beads can thus be distributed freely with varying separation distance.Comment: 12 pages, 2 figures. REVte

    Two interacting diffusing particles on low-dimensional discrete structures

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    In this paper we study the motion of two particles diffusing on low-dimensional discrete structures in presence of a hard-core repulsive interaction. We show that the problem can be mapped in two decoupled problems of single particles diffusing on different graphs by a transformation we call 'diffusion graph transform'. This technique is applied to study two specific cases: the narrow comb and the ladder lattice. We focus on the determination of the long time probabilities for the contact between particles and their reciprocal crossing. We also obtain the mean square dispersion of the particles in the case of the narrow comb lattice. The case of a sticking potential and of 'vicious' particles are discussed.Comment: 9 pages, 6 postscript figures, to appear in 'Journal of Physics A',-January 200

    A Layered Notch filter for High- Frequency Dynamic Isolation

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    An efficient method of isolation from high-frequency vibrations i

    How Well Do We (and Will We) Know Solar Neutrino Fluxes and Oscillation Parameters?

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    Assuming neutrino oscillations occur, the pp electron neutrino flux is uncertain by at least a factor of two, the 8B{\rm ^8B} flux by a factor of five, and the 7Be{\rm ^7Be} flux by a factor of forty-five. Calculations of the expected results of future solar neutrino experiments (SuperKamiokande, SNO, BOREXINO, ICARUS, HELLAZ, and HERON) are used to illustrate the extent to which these experiments will restrict the range of the allowed neutrino mixing parameters. We present an improved formulation of the ``luminosity constraint'' and show that at 95\% confidence limit this constraint establishes the best available limits on the rate of creation of pp neutrinos in the solar interior and provides the best upper limit to the 7Be{\rm ^7Be} neutrino flux.Comment: 37 pages, uuencoded Z-compressed postscript file (with figures); Submitted to Physical Review

    Neutrino masses: From fantasy to facts

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    Theory suggests the existence of neutrino masses, but little more. Facts are coming close to reveal our fantasy: solar and atmospheric neutrino data strongly indicate the need for neutrino conversions, while LSND provides an intriguing hint. The simplest ways to reconcile these data in terms of neutrino oscillations invoke a light sterile neutrino in addition to the three active ones. Out of the four neutrinos, two are maximally-mixed and lie at the LSND scale, while the others are at the solar mass scale. These schemes can be distinguished at neutral-current-sensitive solar & atmospheric neutrino experiments. I discuss the simplest theoretical scenarios, where the lightness of the sterile neutrino, the nearly maximal atmospheric neutrino mixing, and the generation of Δm2⊙\Delta {m^2}_\odot & Δm2atm\Delta {m^2}_{atm} all follow naturally from the assumed lepton-number symmetry and its breaking. Although the most likely interpretation of the present data is in terms of neutrino-mass-induced oscillations, one still has room for alternative explanations, such as flavour changing neutrino interactions, with no need for neutrino mass or mixing. Such flavour violating transitions arise in theories with strictly massless neutrinos, and may lead to other sizeable flavour non-conservation effects, such as Ό→e+Îł\mu \to e + \gamma, Ό−e\mu-e conversion in nuclei, unaccompanied by neutrino-less double beta decay.Comment: 33 pages, latex, 16 figures. Invited Talk at Ioannina Conference, Symmetries in Intermediate High Energy Physics and its Applications, Oct. 1998, to be published by Springer Tracts in Modern Physics. Festschrift in Honour of John Vergados' 60th Birthda

    Constraints on neutrino oscillation parameters from the measurement of day-night solar neutrino fluxes at Super-Kamiokande

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    A search for day-night variations in the solar neutrino flux resulting from neutrino oscillations has been carried out using the 504 day sample of solar neutrino data obtained at Super-Kamiokande. The absence of a significant day-night variation has set an absolute flux independent exclusion region in the two neutrino oscillation parameter space.Comment: 11 pages, 3 figures, submitted to PRL, single-spacin

    Consensus guidelines on analgesia and sedation in dying intensive care unit patients

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    BACKGROUND: Intensivists must provide enough analgesia and sedation to ensure dying patients receive good palliative care. However, if it is perceived that too much is given, they risk prosecution for committing euthanasia. The goal of this study is to develop consensus guidelines on analgesia and sedation in dying intensive care unit patients that help distinguish palliative care from euthanasia. METHODS: Using the Delphi technique, panelists rated levels of agreement with statements describing how analgesics and sedatives should be given to dying ICU patients and how palliative care should be distinguished from euthanasia. Participants were drawn from 3 panels: 1) Canadian Academic Adult Intensive Care Fellowship program directors and Intensive Care division chiefs (N = 9); 2) Deputy chief provincial coroners (N = 5); 3) Validation panel of Intensivists attending the Canadian Critical Care Trials Group meeting (N = 12). RESULTS: After three Delphi rounds, consensus was achieved on 16 statements encompassing the role of palliative care in the intensive care unit, the management of pain and suffering, current areas of controversy, and ways of improving palliative care in the ICU. CONCLUSION: Consensus guidelines were developed to guide the administration of analgesics and sedatives to dying ICU patients and to help distinguish palliative care from euthanasia

    Key components of learning ecologies: a Delphi assessment

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    This is the accepted version of the following article: GonzĂĄlez‐Sanmamed, M. , Muñoz‐Carril, P. and Santos‐Caamaño, F. (2019), Key components of learning ecologies: A Delphi assessment. Br J Educ Technol, 50: 1639-1655, which has been published in final form at https://doi.org/10.1111/bjet.12805. This article may be used for non-commercial purposes in accordance with the Wiley Self-Archiving Policy (http://www.wileyauthors.com/self-archiving)The educational landscape has changed in recent years, requiring reflection about new pedagogical methods and theories. There are three important perspectives as drivers of pedagogical reflection: lifelong and life‐wide learning, the idea of learning as a social construct in which internal elements and changing external factors converge, and the recognition of technology as a resource that can promote ubiquitous and expanded learning. Learning ecology has been proposed as a conceptual and empirical framework, but its still emergent nature along with its multidimensionality and complexity require further exploration. The Delphi study we present as part of a broader research project aims to identify the components of learning ecologies. Three panel rounds with international experts were carried out, after which two important dimensions emerged in the structure of learning ecologies. The first is related to intrinsic “learning dispositions,” which is made up of three categories: the subject's ideas about learning, their motivations and expectations. The second dimension, called “learning processes,” comprises four components: relationships, resources, actions and context. The identification of the components of learning ecologies and their influence on formal, non‐formal and informal training processes will provide guidance for educational policies and help to better organize training programmesWe thank the Spanish Ministry of Economy and Competitiveness for their support of our study under a research project entitled “How the best University Teachers Learn: Impact on Learning Ecologies on Quality of Teaching” (ECO4LEARN‐HE) (Reference: EDU2015‐67907‐R)S

    Standardising Clinical Caremaps: Model, Method and Graphical Notation for Caremap Specification

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    Standardising care can improve patient safety and outcomes, and reduce the cost of providing healthcare services. Caremaps were developed to standardise care, but contemporary caremaps are not standardised. Confusion persists in terms of terminology, structure, content and development process. Unlike existing methods in the literature, the approach, model and notation presented in this chapter pays special attention to incorporation of clinical decision points as first-class citizens within the modelling process. The resulting caremap with decision points is evaluated through creation of a caremap for women with gestational diabetes mellitus. The proposed method was found to be an effective way for comprehensively specifying all features of caremaps in a standardised way that can be easily understood by clinicians. This chapter contributes a new standardised method, model and notation for caremap content, structure and development
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