589 research outputs found
Use of Logical Models for Proving Operational Termination in General Logics
The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-44802-2_2[EN] A declarative programming language is based on some logic L and its operational semantics is given by a proof calculus which is often presented in a natural deduction style by means of inference rules. Declarative programs are theories S of L and executing a program is proving goals ϕ in the inference system I(S) associated to S as a particulariza-tion of the inference system of the logic. The usual soundness assumption for L implies that every model A of S also satisfies ϕ. In this setting, the operational termination of a declarative program is quite naturally defined as the absence of infinite proof trees in the inference system I(S). Proving operational termination of declarative programs often involves two main ingredients: (i) the generation of logical models A to abstract the program execution (i.e., the provability of specific goals in I(S)), and (ii) the use of well-founded relations to guarantee the absence of infinite branches in proof trees and hence of infinite proof trees, possibly taking into account the information about provability encoded by A. In this paper we show how to deal with (i) and (ii) in a uniform way. The main point is the synthesis of logical models where well-foundedness is a side requirement for some specific predicate symbols.Partially supported by the EU (FEDER), Spanish MINECO TIN 2013-45732-C4-1-P and TIN2015-69175-C4-1-R, and GV PROMETEOII/2015/013.Lucas Alba, S. (2016). Use of Logical Models for Proving Operational Termination in General Logics. Lecture Notes in Computer Science. 9942:26-46. https://doi.org/10.1007/978-3-319-44802-2S2646994
Development of a fluorogenic sensor for activated Cdc42
Cdc42, a member of the Rho GTPase family, is a fundamental regulator of the actin cytoskeleton during cell migration. To generate a sensor for Cdc42 activation, we employed a multi-pronged approach, utilizing cysteine labeling and expressed protein ligation, to incorporate the environment sensitive fluorophore 4-N,N-dimethylamino-1,8-naphthalimide (4-DMN) into the GTPase binding domain of the WASP protein. These constructs bind only the active, GTP-bound conformation of Cdc42 to produce a fluorescence signal. Studies with a panel of five sensor analogs revealed a derivative that exhibits a 32-fold increase in fluorescence intensity in the presence of activated Cdc42 compared to incubation with the inactive GDP-bound form of the protein. We demonstrate that this sensor can be exploited to monitor Cdc42 nucleotide exchange and GTPase activity in a continuous, fluorescence assay.National Institutes of Health (U.S.) (Cell Migration Consortium GM064346)National Institute of General Medical Sciences (U.S.) (Biotechnology Training Grant T32-GM08334
Abstract Constraint Data Types
Martin Wirsing is one of the earliest contributors to the area of Algebraic Specification (e.g., [2]), which he explored in a variety of domains over many years. Throughout his career, he has also inspired countless researchers in related areas. This paper is inspired by one of the domains that he explored thirty years or so after his first contributions when leading the FET Integrated Project SENSORIA [14]: the use of constraint systems to deal with non-functional requirements and preferences [13,8]. Following in his footsteps, we provide an extension of the traditional notion of algebraic data type specification to encompass soft-constraints as formalised in [1]. Finally, we relate this extension with institutions [6] and recent work on graded consequence in institutions [3].Peer ReviewedPostprint (author’s final draft
Some geometrical methods for constructing contradiction measures on Atanassov's intuitionistic fuzzy sets
Trillas et al. (1999, Soft computing, 3 (4), 197–199) and Trillas and Cubillo (1999, On non-contradictory input/output couples in Zadeh's CRI proceeding, 28–32) introduced the study of contradiction in the framework of fuzzy logic because of the significance of avoiding contradictory outputs in inference processes. Later, the study of contradiction in the framework of Atanassov's intuitionistic fuzzy sets (A-IFSs) was initiated by Cubillo and Castiñeira (2004, Contradiction in intuitionistic fuzzy sets proceeding, 2180–2186). The axiomatic definition of contradiction measure was stated in Castiñeira and Cubillo (2009, International journal of intelligent systems, 24, 863–888). Likewise, the concept of continuity of these measures was formalized through several axioms. To be precise, they defined continuity when the sets ‘are increasing’, denominated continuity from below, and continuity when the sets ‘are decreasing’, or continuity from above. The aim of this paper is to provide some geometrical construction methods for obtaining contradiction measures in the framework of A-IFSs and to study what continuity properties these measures satisfy. Furthermore, we show the geometrical interpretations motivating the measures
Summa Contra Ontologiam
The final publication is available at Springer via http://dx.doi.org/10.1007/11896548_37Revised Selected Papers of EDBT 2006 Workshops PhD, DataX, IIDB, IIHA, ICSNW, QLQP, PIM, PaRMA, and Reactivity on the Web, Munich, Germany, March 26-31, 2006This paper is a critical analysis of the concept of ontology thus as it is used in contemporary computing science. It identifies three main problems with such a concept, two of which are intrinsic to it and one of which is extrinsic, so to speak, being related to the use that of ontology is made in applications.
The first problem with ontology is that the only accepted definition of its main artifact is teleological rather than structural as it would be proper in computing science. The second problem is that claiming that ontology is in any way a semantic discipline requires such a limited and outdated notion of semantic to be to all practical purposes useless. The third and final problem is that the limitations and misconceptions of ontology might make it a limiting factor, rather than a help, for many of the applications for which it is sought.
The article concludes that a profound reconsideration of the relation between computers and semantics might be overdue
Distilling Privacy Requirements for Mobile Applications
As mobile computing applications have become commonplace, it is increasingly important for them to address end-users’ privacy requirements. Privacy requirements depend on a number of contextual socio-cultural factors to which mobility adds another level of contextual variation. However, traditional requirements elicitation methods do not sufficiently account for contextual factors and therefore cannot be used effectively to represent and analyse the privacy requirements of mobile end users. On the other hand, methods that do investigate contextual factors tend to produce data that does not lend itself to the process of requirements extraction. To address this problem we have developed a Privacy Requirements Distillation approach that employs a problem analysis framework to extract and refine privacy requirements for mobile applications from raw data gathered through empirical studies involving end users. Our approach introduces privacy facets that capture patterns of privacy concerns which are matched against the raw data. We demonstrate and evaluate our approach using qualitative data from an empirical study of a mobile social networking application
Hybridization of institutions
Extended version including all proofsModal logics are successfully used as specification logics for reactive systems. However, they are not expressive enough to refer to individual states and reason about the local behaviour of such systems. This limitation is overcome in hybrid logics which introduce special symbols for naming states in models. Actually, hybrid logics have recently regained interest, resulting in a number of new results and techniques as well as applications to software specification.
In this context, the first contribution of this paper is an attempt to ‘universalize’ the hybridization idea. Following the lines of [DS07], where a method to modalize arbitrary institutions is presented, the paper introduces a method to hybridize logics at the same institution-independent level. The method extends arbitrary institutions with Kripke semantics (for multi-modalities with arbitrary arities) and hybrid features. This paves the ground for a general result: any encoding (expressed as comorphism) from an arbitrary institution to first order logic (FOL) deter- mines a comorphism from its hybridization to FOL. This second contribution opens the possibility of effective tool support to specification languages based upon logics with hybrid features.Fundação para a Ciência e a Tecnologia (FCT
Implicit and explicit stigma towards mental health treatment
In order to better understand stigma associated with mental health treatment, 118 Clemson University students completed Implicit Association Tasks (IAT) and self-report surveys. The IAT presented terms associated with either medical or psychological treatments or patients, paired with additional positive or negative terms (e.g., good vs. bad). Survey items assessed attitudes towards mental health and medical treatment, as well as mental health and medical patients. Responses from the IAT and survey were compared regarding mental health versus medical treatments and mental health versus medical patients. The IAT results revealed a significant negative implicit bias toward mental health treatment and mental health patients. Explicit survey measures also showed more negative responses toward mental health treatment and patients. Our findings provide both implicit and explicit evidence of stigma associated with mental health treatment and patients. Through better understanding these biases, researchers can work to reduce the stigma associated with mental health treatment
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