Introduction to the TPLP special issue, logic programming in databases: From Datalog to semantic-web rules

Much has happened in data and knowledge base research since the introduction of the relational model in Codd (1970) and its strong logical foundations influence its advances ever since. Logic has been a common ground where Database and Artificial Intelligence research competed and collaborated with each other for a long time (Abiteboul et al. 1995). The product of this joint effort has been a set of logic-based formalisms, such as the Relational Calculus (Codd 1970), Datalog (Ceri et al. 1990), Description Logics (Baader et al. 2007), etc., capturing not only the structure but also the semantics of data in an explicit way, thus enabling complex inference procedures.This special issue contains three rigorously reviewed articles addressing problems that span from Query Answering to Data Mining. All these contributions have their roots in the foundational formalisms of Data and Knowledge Bases such as Logic Programming, Description Logic and Hybrid Logics, representing a clear example of the effort that the Database and the Semantic-Web communities are producing to bridge the various schools of thinking in modern Data and Knowledge Management

Evaluating the Effects of Video Modeling and Visual Supports on Preschoolers’ Compliance With Dental Procedures

Individuals with autism are reported to visit the dentist infrequently. Infrequent visits to the dentist may result in a higher occurrence of caries, and it is, therefore, imperative for children with autism to visit a pediatric dental practice routinely. Some basic behaviormanagement techniques, such as live modeling and reinforcement strategies, have been used with patients with autism. The addition of techniques derived from applied behavior analysis, such as video modeling and visual supports, may increase patients’ compliance with dental procedures. Specifically, the use of visual supports and video modeling warranted further investigation on the efficacy of improving behavior during dental procedures

Direct measurement of DNA-mediated adhesion between lipid bilayers

Multivalent interactions between deformable mesoscopic units are ubiquitous in biology, where membrane macromolecules mediate the interactions between neighbouring living cells and between cells and solid substrates. Lately, analogous artificial materials have been synthesised by functionalising the outer surface of compliant Brownian units, for example emulsion droplets and lipid vesicles, with selective linkers, in particular short DNA sequences. This development extended the range of applicability of DNA as a selective glue, originally applied to solid nano and colloidal particles. On very deformable lipid vesicles, the coupling between statistical effects of multivalent interactions and mechanical deformation of the membranes gives rise to complex emergent behaviours, as we recently contributed to demonstrate [Parolini et al., Nature Communications, 2015, 6, 5948]. Several aspects of the complex phenomenology observed in these systems still lack a quantitative experimental characterisation and fundamental understanding. Here we focus on the DNA-mediated multivalent interactions of a single liposome adhering to a flat supported bilayer. This simplified geometry enables the estimate of the membrane tension induced by the DNA-mediated adhesive forces acting on the liposome. Our experimental investigation is completed by morphological measurements and the characterisation of the DNA-melting transition, probed by in-situ F\"{o}rster Resonant Energy Transfer spectroscopy. Experimental results are compared with the predictions of an analytical theory that couples the deformation of the vesicle to a full description of the statistical mechanics of mobile linkers. With at most one fitting parameter, our theory is capable of semi-quantitatively matching experimental data, confirming the quality of the underlying assumptions.Comment: 16 pages, 7 figure

Decentralized robust control of uncertain Markov jump parameter systems via output feedback

This paper addresses the problem of decentralized robust stabilization and control for a class of uncertain Markov jump parameter systems. Control is via output feedback and knowledge of the discrete Markov state. It is shown that the existence of a solution to a collection of mode-dependent coupled algebraic Riccati equations and inequalities, which depend on certain additional parameters, is both necessary and sufficient for the existence of a robust decentralized switching controller. A guaranteed upper bound on robust performance is also given. To obtain a controller which satisfies this bound, an optimization problem involving rank constrained linear matrix inequalities is introduced, and a numerical approach for solving this problem is presented. To demonstrate the efficacy of the proposed approach, an example stabilization problem for a power system comprising three generators and one on-load tap changing transformer is considered. © 2007 Elsevier Ltd. All rights reserved

Organic and healthy: assessing the impact of claims and third-party certifications on premium price

Organic food consumption is steadily growing across a variety of product categories. While consumers are increasingly focused on the healthiness of the food they purchase, companies are experimenting alternative ways to communicate and guarantee the organic and health-related benefits of their products. This study explores the effect of different combinations of front-of-package (FoP) components on premium price. Specifically, we focus on the interaction and visual salience of FoP organic claims, health-related claims, and third-party organic certifications. Based on an analysis of grocery sales data and product packaging visuals, the study identifies FoP component combinations that could maximise premiums. We offer insights to marketing managers and companies involved in enhancing the communication of organic food benefits to consumers

Energetic plumes over the western Ross Sea continental slope

Rapid descent of dense Drygalski Trough (western Ross Sea, Antarctica) shelf water over the continental slope, within 100 to 250 m thick benthic plumes, is described. Speeds of up to 1.0 m/s are recorded flowing at an average angle of 35° to the isobaths, entraining ambient Lower Circumpolar Deep Water en route. This process is predominant in determining the concentration and placement of the shelf water injected into the deep sea as a precursor Antarctic Bottom Water. Nonetheless, a 4-hour duration pulse of undiluted shelf water was observed at depth (1407 m) directly north of the Drygalski Trough, moving at around 90 degrees to isobaths, and at a speed of 1.4 m/s. Thus the export of Ross Sea shelf water to the deep sea is accomplished within plumes descending at moderate angle to isobaths, punctuated by rapid downhill cascades

A bibliometric analysis of the scientific literature on Fairtrade labelling

Since its foundation, the Fairtrade movement has attracted the attention of consumers, practitioners, media and scholars. Discussing the role that Fairtrade can play on a global yet locally rooted scale is very complex, as research reports contrasting results about its usefulness and effectiveness. This study examines scientific research on Fairtrade over the last decades by conducting a bibliometric analysis of the literature published on the ISI Web of Knowledge Core Collection, which included 876 papers by 1,293 authors in 432 journals. Results show that despite this being a relatively recent field of study, Fairtrade has been approached from different disciplines with different methodologies and objectives. The structured quantitative study of the literature enabled us to inspect how research has evolved over the years in the light of the changes faced by Fairtrade, to explore its scope in the broader field of the global market, to detect current research schools and perspectives within the network and to identify hitherto unaddressed issues and unconnected subfields

Photon creation in a spherical oscillating cavity

We study the photon creation inside a perfectly conducting, spherical oscillating cavity. The electromagnetic field inside the cavity is described by means of two scalar fields which satisfy Dirichlet and (generalized) Neumann boundary conditions. As a preliminary step, we analyze the dynamical Casimir effect for both scalar fields. We then consider the full electromagnetic case. The conservation of angular momentum of the electromagnetic field is also discussed, showing that photons inside the cavity are created in singlet states.Comment: 14 pages, no figure

Dagli osservatóri agli Osservatòri

Quelli che hanno avuto il Vesuvio negli occhi, le loro storie di scienziati e di uomini, sono il tema di questo breve racconto. Storie di osservatóri, quindi, che hanno studiato il vulcano con passione, affascinati e sedotti da una montagna umbratile e solenne. Ma anche storie di Osservatòri, di contesti e tempi, ovvero, anch’essi mutevoli, in cui la scienza si organizza e si disorganizza per comprendere, prevedere, provvedere

Fluorination Enables a Ligand-Controlled Regiodivergent Palladium-Catalyzed Decarboxylative Allylation Reaction to Access α,α-Difluoroketones

This is the peer reviewed version of the following article: Yang, M., Orsi, D. L., & Altman, R. A. (2015). Fluorination Enables a Ligand-Controlled Regiodivergent Palladium-Catalyzed Decarboxylative Allylation Reaction to Access α,α-Difluoroketones. Angewandte Chemie (International Ed. in English), 54(8), 2361–2365. http://doi.org/10.1002/anie.201410039, which has been published in final form at doi.org/10.1002/anie.201410039. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.α,α-Difluoroketones possess unique physicochemical properties that are useful for developing therapeutics and probes for chemical biology. In order to access the α-allyl-α,α-difluoroketone substructure, complementary Pd-catalyzed decarboxylative allylation reactions were developed to provide linear and branched α-allyl-α,α-difluoroketones. For these orthogonal processes, the regioselectivity was uniquely controlled by fluorination of the substrate and the structure of ligand