Problems and results in tame congruence theory. A survey of the '88 Budapest workshop

1992 ◽  
Vol 29 (2) ◽  
pp. 151-171 ◽  
Author(s):  
Emil W. Kiss ◽  
Peter Pr�hle
1993 ◽  
Vol 30 (4) ◽  
pp. 479-520 ◽  
Author(s):  
Joel Berman ◽  
Steven Seif

1997 ◽  
Vol 07 (01) ◽  
pp. 55-75 ◽  
Author(s):  
Emil W. Kiss

A finite algebra C is called minimal with respect to a pair δ<θ of its congruences if every unary polynomial f of C is either a permutation, or f(θ)⊆δ. It is the basic idea of tame congruence theory developed by Ralph McKenzie and David Hobby [7] to describe finite algebras via minimal algebras that sit inside them. As shown in [7] minimal algebras have a very restricted structure. This paper presents a new tool, the Twin Lemma, which makes it possible to give short proofs of some of these structure theorems. This part can be read as an alternative introduction to the theory. Our method yields new information in the type 1 case, and is especially useful in describing E-minimal algebras (that is, algebras that are minimal with respect to every prime congruence quotient). We complete their theory given in [7] by proving a structure theorem for the type 1 case. Finally we show that if an algebra is minimal with respect to two quotients, then the two types are the same, and if this type is 2, 3, or 4, then the bodies are also equal.


2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Anamarija Butković ◽  
Rubén González ◽  
Inés Cobo ◽  
Santiago F Elena

Abstract Robustness is the preservation of the phenotype in the face of genetic and environmental perturbations. It has been argued that robustness must be an essential fitness component of RNA viruses owed to their small and compacted genomes, high mutation rates and living in ever-changing environmental conditions. Given that genetic robustness might hamper possible beneficial mutations, it has been suggested that genetic robustness can only evolve as a side-effect of the evolution of robustness mechanisms specific to cope with environmental perturbations, a theory known as plastogenetic congruence. However, empirical evidences from different viral systems are contradictory. To test how adaptation to a particular environment affects both environmental and genetic robustness, we have used two strains of turnip mosaic potyvirus (TuMV) that differ in their degree of adaptation to Arabidopsis thaliana at a permissive temperature. We show that the highly adapted strain is strongly sensitive to the effect of random mutations and to changes in temperature conditions. In contrast, the non-adapted strain shows more robustness against both the accumulation of random mutations and drastic changes in temperature conditions. Together, these results are consistent with the predictions of the plastogenetic congruence theory, suggesting that genetic and environmental robustnesses may be two sides of the same coin for TuMV.


1977 ◽  
Vol 22 (2) ◽  
pp. 264 ◽  
Author(s):  
Donald V. Nightingale ◽  
Jean-Marie Toulouse

Author(s):  
Rita Koganzon

The conclusion summarizes the reasons for Locke’s and Rousseau’s turn against absolutist congruence theory and toward a defense of authoritarian families in liberal states. They saw that the absolutists had failed to adequately grapple with the power of public opinion to undermine the sovereign authority that was supposed to control it, and they understood the enormous influence of opinion over our ideas and its potential to foreclose intellectual freedom. To defend that freedom for adults, they leaned on the family and its domestic education of children as a buttress and counterinfluence against the power of fashion and opinion. Recognizing this pedagogical role of personal authority in the foundations of liberalism may help us to resolve our own inability to find a place for the basic but private experience of personal authority, which, however much we wish it away, remains central to forming liberal public life


2020 ◽  
Vol 57 ◽  
pp. 102228
Author(s):  
Michael S.W. Lee ◽  
Felix Septianto ◽  
Catherine Frethey-Bentham ◽  
Esther Gao
Keyword(s):  

2020 ◽  
pp. 107780122095217
Author(s):  
Jamie A. Snyder ◽  
Heidi L. Scherer ◽  
Bonnie S. Fisher

Past research has shown that a significant proportion of college students will experience a victimization during their college tenure. This body of research provides evidence that college students’ lifestyle characteristics and routine activities play a role in influencing their risk of victimization; yet, little is known about whether these same risk factors predict both single-type victimization and poly-victimization. Using a sample of more than 4,000 college women from across the United States, multivariate analyses were used to examine the risk factors for poly-victimization. Measures from both target congruence theory and lifestyles-routine activities theory were found to significantly differentiate single-type victims from poly-victims.


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