Between Hilbert and Gentzen: four-valued consequence systems and structural reasoning

Author(s):  
Yaroslav Shramko
Keyword(s):  
2016 ◽  
Vol 71 (7) ◽  
pp. 765-776 ◽  
Author(s):  
Naglaa F. El-Sayed ◽  
Ewies F. Ewies ◽  
Marwa El-Hussieny ◽  
Leila S. Boulos ◽  
ElSayed M. Shalaby

AbstractThe reactions of 5-azido-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde (azidopyrazole) with several classes of organophosphorus reagents: phosphonium ylides, Wittig-Horner reagents, dialkylphosphonates, trialkylphosphites, tris(dialkylamino)phosphanes, triphenylstibane, triphenylarsane, and Lawesson’s reagent are reported. Structural reasoning for the new products was based on compatible analytical and spectral data. The cytotoxic activity of most of the new products was evaluated against human breast carcinoma cell line (MCF7) and human hepatocellular carcinoma cell line(HepG2). Certain tested compounds showed promising results.


2020 ◽  
Vol 113 (10) ◽  
pp. 812-820
Author(s):  
Hyung Sook Lee ◽  
Jaehoon Yim, ◽  
Jacqueline Coomes
Keyword(s):  

Advance students' strategies by highlighting properties, diverting attention away from procedures and algebraic skills to see the structures in expressions.


2007 ◽  
Vol 17 (4-5) ◽  
pp. 473-546 ◽  
Author(s):  
MARTIN BERGER ◽  
KOHEI HONDA ◽  
NOBUKO YOSHIDA

AbstractWe present a compositional programme logic for call-by-value imperative higher-order functions with general forms of aliasing, which can arise from the use of reference names as function parameters, return values, content of references and parts of data structures. The programme logic extends our earlier logic for alias-free imperative higher-order functions with new operators which serve as building blocks for clean structural reasoning about programms and data structures in the presence of aliasing. This has been an open issue since the pioneering work by Cartwright–Oppen and Morris twenty-five years ago. We illustrate usage of the logic for description and reasoning through concrete examples including a higher-order polymorphic Quicksort. The logical status of the new operators is clarified by translating them into (in)equalities of reference names.


2015 ◽  
Vol 8 (4) ◽  
pp. 662-679 ◽  
Author(s):  
ENRICO MORICONI

AbstractThis paper is a study of the opening section of Gentzen’s first publication of 1932, Über die Existenz unabhängiger Axiomensysteme zu unendlichen Satzsystemen, a text which shows the relevance of Hertz’s work of the 1920’s for the young Gentzen. In fact, Gentzen borrowed from Hertz the analysis of the notion of consequence, which was given in terms of the rules of thinning (Verdünnung) and cut (Schnitt) on sequents (there called “sentences”(Sätze)). Moreover, following Hertz again, he also judged it necessary to justify the forms of inference of the system by providing a semantics for them, so that it became possible to make precise the informal notion of consequence, and to show that the inference rules adopted are correct and sufficient.


2019 ◽  
Vol 112 (4) ◽  
pp. 294-301
Author(s):  
Casey Hawthorne ◽  
Bridget K. Druken

Examples of solving equations and inequalities, analyzing quadratic expressions, and reasoning with functions show three ways to engage students in this mathematical practice.


Sign in / Sign up

Export Citation Format

Share Document