Embedding logical frameworks in scala

El Framework Lógico de Edimburgo ha demostrado ser una poderosa herramienta en el estudio formal de sistemas deductivos, como por ejemplo lenguajes de programación. Sin embargo su principal implementación, el sistema Twelf, carece de expresividad, obligando al programador a escribir código repetitivo. Este proyecto presenta una manera alternativa de utilizar Twelf: a través de un EDSL (Lenguaje Embebido de Dominio Específico) en Scala que permite representar firmas del Framework Lógico, y apoyándonos en Twelf como backend para la verificación, abrimos la puerta a diversas posibilidades en términos de metaprogramación. El código fuente, así como instrucciones para instalar y configurar, está accesible en https://github.com/akathorn/elfcala. ---ABSTRACT---The Edinburgh Logical Framework has proven to be to be a powerful tool in the formal study of deductive systems, such as programming languages. However, its main implementation, the Twelf system, lacks expressiveness, requiring the programmer to write repetitive code. This project presents an alternative way of using Twelf: by providing a Scala EDSL (Embedded Domain Specific Language) that can encode Logical Framework signatures and relying on Twelf as a backend for the verification, we open the door to different possibilities in terms of metaprogramming. The source code, along with instructions to install and configure, is accessible at https://github.com/akathorn/elfcala

A logical analysis of T cell activation and anergy

Interaction of the antigen-specific receptor of T lymphocytes with its antigenic ligand can lead either to cell activation or to a state of profound unresponsiveness (anergy). Although subtle changes in the nature of the ligand or of the antigen-presenting cell have been shown to affect the outcome of T cell receptor ligation, the mechanism by which the same receptor can induce alternative cellular responses is not completely understood. A model for explaining both positive (cell proliferation and cytokine production) and negative (anergy induction) signaling of T lymphocytes is described herein. This model relies on the autophosphorylative properties of the tyrosine kinases associated with the T cell receptor. One of its basic assumptions is that the kinase activity of these receptor-associated enzymes remains above background level after ligand removal and is responsible for cellular unresponsiveness. Using a simple Boolean formalism, we show how the timing of the binding and intracellular signal-transduction events can affect the properties of receptor signaling and determine the type of cellular response. The present approach integrates into a common framework a large body of experimental observations and allows specification of conditions leading to cellular activation or to anergy.

Cells that register logical relationships among proteins

Two-hybrid methods have augmented the classical genetic techniques biologists use to assign function to genes. Here, we describe construction of a two-bait interaction trap that uses yeast cells to register more complex protein relationships than those detected in existing two-hybrid systems. We show that such cells can identify bridge or connecting proteins and peptide aptamers that discriminate between closely related allelic variants. The protein relationships detected by these cells are analogous to classical genetic relationships, but lend themselves to systematic application to the products of entire genomes and combinatorial libraries. We show that, by performing logical operations on the phenotypic outputs of these complex cells and existing two-hybrid cells, we can make inferences about the topology and order of protein interactions. Finally, we show that cells that register such relationships can perform logical operations on protein inputs. Thus these cells will be useful for analysis of gene and allele function, and may also define a path for construction of biological computational devices.

Modelling logical expressions exercises

Exercises of application of the systematic procedure to derive linear inequalities for logic expressions (Ejercicios de aplicación del método sistemático de obtención de restricciones lineales para expresiones lógicas).

In a state of necessity. How has Orban changed Hungary. OSW Point of View Number 41, April 2014

Viktor Orban’s sweeping victory in the 2010 election ensured his party, Fidesz, a constitutional two-thirds majority in parliament. The party took over the rule of the country from the discredited political left when Hungary was plunged in political and economic crisis. Claiming that the circumstances were unusual and that it had a strong electoral mandate, Fidesz introduced radical changes in the country and thus challenged the previous economic and political order. These changes have led to an unprecedented concentration of power and provoked a discussion on the limits of democracy and the rule of law in the European Union. The state’s economic role has strengthened. The Orban government has been unable to overcome economic stagnation but it has managed to stabilise Hungary’s budget situation, which needs to deal with the high debt. Hungary’s relations with most partners in the EU and NATO have cooled due to controversial moves made by its government. As regards foreign policy and economic co-operation, Orban has granted high priority to the ‘Eastern opening’, where Russia has assumed the leading role.

Logical Modeling and Dynamical Analysis of Cellular Networks

The logical (or logic) formalism is increasingly used to model regulatory and signaling networks. Complementing these applications, several groups contributed various methods and tools to support the definition and analysis of logical models. After an introduction to the logical modeling framework and to several of its variants, we review here a number of recent methodological advances to ease the analysis of large and intricate networks. In particular, we survey approaches to determine model attractors and their reachability properties, to assess the dynamical impact of variations of external signals, and to consistently reduce large models. To illustrate these developments, we further consider several published logical models for two important biological processes, namely the differentiation of T helper cells and the control of mammalian cell cycle.

Our weakened Constitution : an historical and analytical study of the Constitution of the United States and of the additions to the original text undertaken to place the facts before the American people, and to emphasize the present necessity for a movement in behalf of an unvolated Constitution, state integrity and the rights and immunities established by the founders of this republic /

Mode of access: Internet.

On the necessity of cultivating water bacteria in an atmosphere saturated with moisture.

Mode of access: Internet.

Interstate and foreign transportation : hearings before the Joint Committee on Interstate and Foreign Commerce, Congress of the United States, pursuant to Public J. Res. 25, a joint resolution creating a joint subcommittee from the membership of the Senate Committee on Interstate Commerce and the House Committee on Interstate and Foreign Commerce to investigate the conditions relating to interstate and foreign commerce, and the necessity of further legislation relating thereto, and defing the powers and duties of such subcommittee.

Printed for the use of the Joint Committee on Interstate Commerce.

Observations on the marriage laws, particularly in reference to the case of desertion, or a fraudulent and violated contract ... demonstrating the necessity of legislative interference .

Mode of access: Internet.

Proposed land legislation for states and nation especially published in the interest of every man and woman interested in the home : a logical remedy for the "Bread Basket" speculator and unscrupulous real estate operators based on economy, efficiency, justice for humanity /

Mode of access: Internet.

Comparison of the implicit enumeration method and the branch-and-bound method for logical design

Bibliography: p. 91-94.

A study of the effect of additional inequalities in integer programming for logical design.

Originally presented as the author's thesis (M.S.), University of Illinois at Urbana-Champaign.

Arithmetic unit of Illiac III: simulation and logical design, part II,

Pt 1, by Daniel E. Atkins, issued as File no. 713 of the University of Illinois Dept. of Computer Science in 1966.