125,889 research outputs found
Oscillations in SIR behavioural epidemic models: The interplay between behaviour and overexposure to infection
No full textOscillations in epidemic models including human behaviour indicate that the human factor might play a key role in the occurrence of periodically high levels of incidence and prevalence of the disease. Such phenomena can be captured even with minimal models, i.e. basic SIR or SEIR models with a reduced mathematical complexity. In such models, the effects of information-dependent changes in contact patterns are strongly affected by the function used to describe the memory of the population. In particular, the endemic equilibrium cannot be destabilized in case of exponentially fading memory but sustained oscillations are possible when the memory of the population is described by certain unimodal functions. In this work, we introduce a behavioural SIR-like model with information-dependent social distancing to investigate the interplay between individuals’ behaviour and overexposure to infection due to unconscious exposure to contagion. We use spectral analysis to show that sustained oscillations may take place even with exponentially fading memory. We show that this result holds both in case of prevalence-based and incidence-based social distancing. Furthermore, we show that the individual's behavioural response to information may stabilize the oscillations induced by overexposure
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Analysis of an epidemic model with peer-pressure and information-dependent transmission with high-order distributed delay
No full textFractional monodromy: parallel transport of homology cycles
No full textA 2n-dimensional completely integrable system gives rise to a singular fibration whose generic fiber is the n-torus. In the classical setting, it is possible to define a parallel transport of elements of the first homotopy group of a fiber along a path, when the path describes a loop around a singular fiber, it defines an automorphism of the fundamental group of the torus called monodromy transformation [J.J. Duistermaat, On global action-angle coordinates, Communications on Pure and Applied Mathematics 33 (6) (1980) 687– 706]. Some systems give rise to a non-classical setting, in which the path can wind around a singular fiber only by crossing a codimension 1 submanifold of special singular fibers (a wall), in this case a non-classical parallel transport can be defined on a subgroup of the fundamental group. This gives rise to what is known as monodromy with fractional coefficients [N. Nekhoroshev, D. Sadovskiì, B. Zhilinskiì, Fractional monodromy of resonant classical and quantum oscillators, Comptes Rendus Mathematique 335 (11) (2002) 985–988]. In this article, we give a precise meaning to the non-classical parallel transport. In particular we show that it is a homologic process and not a homotopic one. We justify this statement by describing the type of singular fibers that generate a wall that can be crossed, by describing the parallel transport in a semi-local neighbourhood of the wall of singularities, and by producing a family of 4-dimensional examples
Some results in the nonlinear stability for rotating Bénard problem with rigid boundary condition
No full textThe scope of this article is to expose the stabilizing properties of rotation and solute gradient for the Bénard problem with (at least one-sided) rigid boundary conditions. We perform a linear investigation of the critical threshold for the rotating Bénard problem with a binary fluid, and we also make an investigation with a Lyapunov function for the particular problem of a rotating single fluid. In all the these cases an increase of the Taylor number has stabilizing effects
Figure 1 in Ecological notes of the alien species Godiva quadricolor (Gastropoda: Nudibranchia) occurring in Faro Lake (Italy)
No full textFigure 1. Italian distribution of Polycera hedgpethi (letters, square) and Godiva quadricolor (numbers, circles). 1: north Adriatic lagoon, Zenetos et al. (2016); 2: Noli, Ligurian Sea, Betti et al. (2015); 3: Sabaudia Lake, Macali et al. (2013); 4: Fusaro Lake, Gulf of Naples, Cervera et al. (2010); 5: Faro Lake, Sicily, present study. A: Sacca Sessola Island, Venice Lagoon, Italy (Keppel et al. 2012); B: Marina di Ravenna docks, Italy (Rudman 2005; Trainito 2005); C: Rimini coast, Italy (Ioni, 2011); D: Fusaro Lake, Gulf of Naples, Cervera et al. 1991 (1988)); E: Faro Lake, Sicily, Giacobbe and De Matteo (2013).Published as part of Furfaro, Giulia, De Matteo, Sergio, Mariottini, Paolo & Giacobbe, Salvatore, 2018, Ecological notes of the alien species Godiva quadricolor (Gastropoda: Nudibranchia) occurring in Faro Lake (Italy), pp. 645-657 in Journal of Natural History 52 (11-12) on page 646, DOI: 10.1080/00222933.2018.1445788, http://zenodo.org/record/517429
Pragmatic Case Studies as a Source of Unity in Applied Psychology
No full textTo unify or not to unify applied psychology: that is the question. In this article we review pendulum swings in the historical efforts to answer this question—from a comprehensive, positivist, “top-down,” deductive yes between the 1930s and the early 60s, to a postmodern no since then. A rationale and proposal for a limited, “bottom-up,” inductive yes in applied psychology is then presented, employing a case-based paradigm that integrates both positivist and postmodern themes and components. This paradigm is labeled “pragmatic psychology” and, its specific use of case studies, the “Pragmatic Case Study Method” (“PCS Method”). We call for the creation of peer-reviewed journal-databases of pragmatic case studies as a foundational source of unifying applied knowledge in our discipline. As one example, the potential of the PCS Method for unifying different angles of theoretical regard is illustrated in an area of applied psychology, psychotherapy, via the case of Mrs. B. The article then turns to the broader historical and epistemological arguments for the unifying nature of the PCS Method in both applied and basic psychology.Peer reviewe
Monodromy of the quantum 1:1:2 resonant swing spring
No full textWe describe the qualitative features of the joint spectrum of the quantum 1:1:2 resonant swing spring. The monodromy of the classical analogue of this problem is studied in Dullin et al. [Physica D 190, 15–37 (2004)]. Using symmetry arguments and numerical calculations we compute its three-dimensional (3D) lattice of quantum states and show that it possesses a codimension 2 defect characterized by a nontrivial 3D-monodromy matrix. The form of the monodromy matrix is obtained from the lattice of quantum states and depends on the choice of an elementary cell of the lattice. We compute the quantum monodromy matrix, that is the inverse transpose of the classical monodromy matrix. Finally we show that the lattice of quantum states for the 1:1:2 quantum swing spring can be obtained—preserving the symmetries—from the regular 3D-cubic lattice by means of three “elementary monodromy cuts”
Dr. Edwin Wright Collection: Author Unknown
No full textNotes - The author relates several short stories about his neighbours including Alex McDonell, homesteading and life around Meanook and Athabasca (1 page
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