Results for 'congruence uniform variety'

982 found
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  1.  94
    On the variety of M -generalized łukasiewicz algebras of order N.Júlia Vaz de Carvalho - 2010 - Studia Logica 94 (2):291-305.
    In this paper we pursue the study of the variety of m -generalized Łukasiewicz algebras of order n which was initiated in [1]. This variety contains the variety of Łukasiewicz algebras of order n . Given , we establish an isomorphism from its congruence lattice to the lattice of Stone filters of a certain Łukasiewicz algebra of order n and for each congruence on A we find a description via the corresponding Stone filter. We characterize (...)
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  2.  19
    Uniform interpolation and compact congruences.Samuel J. van Gool, George Metcalfe & Constantine Tsinakis - 2017 - Annals of Pure and Applied Logic 168 (10):1927-1948.
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  3.  22
    Ralph Freese and Ralph McKenzie. Commutator theory for congruence modular varieties. London Mathematical Society lecture note series, no. 125. Cambridge University Press, Cambridge etc. 1987, iii + 227 pp. [REVIEW]Matthew Valeriote - 1989 - Journal of Symbolic Logic 54 (3):1114-1115.
  4.  19
    Review: Ralph Freese, Ralph McKenzie, Commutator Theory for Congruence Modular Varieties. [REVIEW]Matthew Valeriote - 1989 - Journal of Symbolic Logic 54 (3):1114-1115.
  5.  19
    Relatively congruence-distributive subquasivarieties of filtral varieties.Janusz Czelakowski - 1990 - Bulletin of the Section of Logic 19 (2):66-70.
  6.  11
    Decomposition of Congruence Modular Algebras into Atomic, Atomless Locally Uniform and Anti-Uniform Parts.Bogdan Staruch & Bożena Staruch - 2016 - Bulletin of the Section of Logic 45 (3/4).
    We describe here a special subdirect decomposition of algebras with modular congruence lattice. Such a decomposition is based on the properties of the congruence lattices of algebras. We consider four properties of lattices: atomic, atomless, locally uniform and anti-uniform. In effect, we describe a star-decomposition of a given algebra with modular congruence lattice into two or three parts associated to these properties.
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  7.  25
    Value Uniformity and Variety.William C. Frederick - 1995 - The Ruffin Series in Business Ethics:119-119.
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  8.  18
    On Solvable Congruences in Finitely Decidable Varieties.Matthew A. Valeriote - 1994 - Mathematical Logic Quarterly 40 (3):398-414.
    In this paper we establish the - and -transfer principles for finitely decidable locally finite varieties, where a class of structures is finitely decidable if the first order theory of its finite members is recursive. The transfer principles deal with the local structure of finite algebras and have strong global consequences.
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  9.  11
    From a variety of ethics to the integrity and congruence of research on biodiversity conservation.Claire Lajaunie - 2018 - Asian Bioethics Review 10 (4):313-332.
    This article aims to find the elements that are required for a common ethical approach that is suitable for the different perspectives adopted in integrative biodiversity conservation research. A general reflection on the integrity of research is a priority worldwide, with a common aim to promote good research practice. Beyond the relationship between researcher and research subject, the integrity of research is considered in a broader perspective which entails scientific integrity towards society. In research involving a variety of disciplines (...)
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  10.  22
    On factoring by compact congruences in algebras of certain varieties related to the intuitionistic logic.Andrzej Wronski - 1986 - Bulletin of the Section of Logic 15 (2):48-51.
    This is a summary of a talk delivered at the Winter School of Logic held in Rabka, 24.02 – 04.03.1986 by the Department of Logic of the Jagiellonian University. We wish to announce here several results on embeddability of quotient algebras of certain kind into algebras of some varieties related to the class of Heyting algebras. A “by product” is the deduction theorem for a large family of intermediate consequence operations.
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  11.  21
    Bjarni Jónsson. Appendix 3. Congruence varieties. Therein, pp. 348–377.Heinrich Werner - 1982 - Journal of Symbolic Logic 47 (2):451.
  12.  9
    Quasi-subtractive varieties: Open filters, congruences and the commutator.T. Kowalski, A. Ledda & F. Paoli - 2014 - Logic Journal of the IGPL 22 (6):844-871.
  13.  54
    A Finite Basis Theorem For Residually Finite, Congruence Meet-semidistributive Varieties.Ross Willard - 2000 - Journal of Symbolic Logic 65 (1):187-200.
    We derive a Mal'cev condition for congruence meet-semidistributivity and then use it to prove two theorems. $\mathbf{Theorem A:}$ if a variety in a finite language is congruence meet-semidistributive and residually less than some finite cardinal, then it is finitely based. $\mathbf{Theorem B:}$ there is an algorithm which, given $m < \omega$ and a finite algebra in a finite language, determines whether the variety generated by the algebra is congruence meet-semidistributive and residually less than m.
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  14.  5
    Imprecision, between variety and uniformity: the conjugate pairs.Solomon Marcus - 1998 - Poznan Studies in the Philosophy of the Sciences and the Humanities 62:59-72.
  15. A Uniform Account of Regress Problems.David Löwenstein - 2017 - Acta Analytica 32 (3).
    This paper presents a uniform general account of regress problems in the form of a pentalemma—i.e., a set of five mutually inconsistent claims. Specific regress problems can be analyzed as instances of such a general schema, and this Regress Pentalemma Schema can be employed to generate deductively valid arguments from the truth of a subset of four claims to the falsity of the fifth. Thus, a uniform account of the nature of regress problems allows for an improved understanding (...)
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  16.  38
    Congruence Coherent Symmetric Extended de Morgan Algebras.T. S. Blyth & Jie Fang - 2007 - Studia Logica 87 (1):51-63.
    An algebra A is said to be congruence coherent if every subalgebra of A that contains a class of some congruence on A is a union of -classes. This property has been investigated in several varieties of lattice-based algebras. These include, for example, de Morgan algebras, p-algebras, double p-algebras, and double MS-algebras. Here we determine precisely when the property holds in the class of symmetric extended de Morgan algebras.
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  17.  20
    Factor Congruence Lifting Property.George Georgescu & Claudia Mureşan - 2017 - Studia Logica 105 (1):179-216.
    In previous work, we have introduced and studied a lifting property in congruence–distributive universal algebras which we have defined based on the Boolean congruences of such algebras, and which we have called the Congruence Boolean Lifting Property. In a similar way, a lifting property based on factor congruences can be defined in congruence–distributive algebras; in this paper we introduce and study this property, which we have called the Factor Congruence Lifting Property. We also define the Boolean (...)
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  18.  30
    Effects of Internal–External Congruence-Based CSR Positioning: An Attribution Theory Approach.Whitney Ginder, Wi-Suk Kwon & Sang-Eun Byun - 2019 - Journal of Business Ethics 169 (2):355-369.
    Although corporate social responsibility appears to be mutually beneficial for companies and consumers, the modern marketplace has left both parties in vulnerable positions. Consumers are increasingly subjected to incongruent CSR messages such as greenwashing, while companies are trapped in a strategic positioning dilemma with regard to how to most effectively and ethically approach CSR communication. This has led some companies to instead adopt a strategically silent approach, such as greenhushing. To capture this CSR positioning dilemma and test the positioning effects (...)
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  19.  21
    Definable principal congruences and solvability.Paweł M. Idziak, Keith A. Kearnes, Emil W. Kiss & Matthew A. Valeriote - 2009 - Annals of Pure and Applied Logic 157 (1):30-49.
    We prove that in a locally finite variety that has definable principal congruences , solvable congruences are nilpotent, and strongly solvable congruences are strongly abelian. As a corollary of the arguments we obtain that in a congruence modular variety with DPC, every solvable algebra can be decomposed as a direct product of nilpotent algebras of prime power size.
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  20.  21
    Quasivarieties and Congruence Permutability of Łukasiewicz Implication Algebras.M. Campercholi, D. Castaño & J. P. Díaz Varela - 2011 - Studia Logica 98 (1-2):267-283.
    In this paper we study some questions concerning Łukasiewicz implication algebras. In particular, we show that every subquasivariety of Łukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite Łukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.
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  21.  17
    Principal and Boolean Congruences on $$\varvec{IKt}$$ IKt -Algebras.Aldo V. Figallo, Inés Inés Pascual & Gustavo Pelaitay - 2018 - Studia Logica 106 (4):857-882.
    The IKt-algebras were introduced in the paper An algebraic axiomatization of the Ewald’s intuitionistic tense logic by the first and third author. In this paper, our main interest is to investigate the principal and Boolean congruences on IKt-algebras. In order to do this we take into account a topological duality for these algebras obtained in Figallo et al. :673–701, 2017). Furthermore, we characterize Boolean and principal IKt-congruences and we show that Boolean IKt-congruence are principal IKt-congruences. Also, bearing in mind (...)
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  22.  93
    The logic of distributive bilattices.Félix Bou & Umberto Rivieccio - 2011 - Logic Journal of the IGPL 19 (1):183-216.
    Bilattices, introduced by Ginsberg as a uniform framework for inference in artificial intelligence, are algebraic structures that proved useful in many fields. In recent years, Arieli and Avron developed a logical system based on a class of bilattice-based matrices, called logical bilattices, and provided a Gentzen-style calculus for it. This logic is essentially an expansion of the well-known Belnap–Dunn four-valued logic to the standard language of bilattices. Our aim is to study Arieli and Avron’s logic from the perspective of (...)
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  23. Three varieties of causal overdetermination.Eric Funkhouser - 2002 - Pacific Philosophical Quarterly 83 (4):335-351.
    Causal overdetermination worries arise in a number of domains, but most notably in the philosophy of mind. ln discussions of such worries, alleged examples of causal overdetermination are uniformly viewed as primajzcie problematic. While all alleged cases of overdetermination might be problematic, I aim to show that they are so for different reasons. Examples of causal overdetermination neatly divide into three varieties, corresponding to the connections between the mechanisms and the properties of the causes. Future debates over overdetermination, and mental (...)
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  24.  42
    Varieties of pseudo-interior algebras.Barbara Klunder - 2000 - Studia Logica 65 (1):113-136.
    The notion of a pseudo-interior algebra was introduced by Blok and Pigozzi in [BPIV]. We continue here our studies begun in [BK]. As a consequence of the representation theorem for pseudo-interior algebras given in [BK] we prove that the variety of all pseudo-interior algebras is generated by its finite members. This result together with Jónsson's Theorem for congruence distributive varieties provides a useful technique in the study of the lattice of varieties of pseudo-interior algebras.
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  25.  45
    On ockham algebras: Congruence lattices and subdirectly irreducible algebras.P. Garcia & F. Esteva - 1995 - Studia Logica 55 (2):319 - 346.
    Distributive bounded lattices with a dual homomorphism as unary operation, called Ockham algebras, were firstly studied by Berman (1977). The varieties of Boolean algebras, De Morgan algebras, Kleene algebras and Stone algebras are some of the well known subvarieties of Ockham algebra. In this paper, new results about the congruence lattice of Ockham algebras are given. From these results and Urquhart's representation theorem for Ockham algebras a complete characterization of the subdirectly irreducible Ockham algebras is obtained. These results are (...)
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  26.  11
    Semisimplicity and Congruence 3-Permutabilty for Quasivarieties with Equationally Definable Principal Congruences.Miguel Campercholi & Diego Vaggione - forthcoming - Studia Logica:1-11.
    We show that the properties of [relative] semisimplicity and congruence 3-permutability of a [quasi]variety with equationally definable [relative] principal congruences (EDP[R]C) can be characterized syntactically. We prove that a quasivariety with EDPRC is relatively semisimple if and only if it satisfies a finite set of quasi-identities that is effectively constructible from any conjunction of equations defining relative principal congruences in the quasivariety. This in turn allows us to obtain an ‘axiomatization’ of relatively filtral quasivarieties. We also show that (...)
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  27.  23
    On Principal Congruences in Distributive Lattices with a Commutative Monoidal Operation and an Implication.Hernán Javier San Martín & Ramon Jansana - 2019 - Studia Logica 107 (2):351-374.
    In this paper we introduce and study a variety of algebras that properly includes integral distributive commutative residuated lattices and weak Heyting algebras. Our main goal is to give a characterization of the principal congruences in this variety. We apply this description in order to study compatible functions.
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  28.  31
    Quasivarieties and Congruence Permutability of Łukasiewicz Implication Algebras.M. Campercholi, D. Castaño & J. Díaz Varela - 2011 - Studia Logica 98 (1-2):267-283.
    In this paper we study some questions concerning Łukasiewicz implication algebras. In particular, we show that every subquasivariety of Łukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite Łukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.
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  29.  11
    Polynomial Time Uniform Word Problems.Stanley Burris - 1995 - Mathematical Logic Quarterly 41 (2):173-182.
    We have two polynomial time results for the uniform word problem for a quasivariety Q: The uniform word problem for Q can be solved in polynomial time iff one can find a certain congruence on finite partial algebras in polynomial time. Let Q* be the relational class determined by Q. If any universal Horn class between the universal closure S and the weak embedding closure S̄ of Q* is finitely axiomatizable then the uniform word problem for (...)
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  30.  12
    How Does It Fit? Exploring the Congruence Between Organizations and Their Corporate Social Responsibility (CSR) Activities.Mark Meer & Menno Jong - 2017 - Journal of Business Ethics 143 (1):71-83.
    Several studies have focused on the effects of corporate social responsibility fit on external stakeholders’ evaluations of CSR activities, attitudes towards companies or brands, and behaviors. The results so far have been contradictory. A possible reason may be that the concept of CSR fit is more complicated than previously assumed. Researchers suggest that there may be different types of CSR fit, but so far no empirical research has focused on a typology of CSR fit. This study fills this gap, describing (...)
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  31.  23
    On Principal Congruences in Distributive Lattices with a Commutative Monoidal Operation and an Implication.Ramon Jansana & Hernán Javier San Martín - 2019 - Studia Logica 107 (2):351-374.
    In this paper we introduce and study a variety of algebras that properly includes integral distributive commutative residuated lattices and weak Heyting algebras. Our main goal is to give a characterization of the principal congruences in this variety. We apply this description in order to study compatible functions.
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  32.  27
    A topology induced by uniformity on BL‐algebras.Masoud Haveshki, Esfandiar Eslami & Arsham Borumand Saeid - 2007 - Mathematical Logic Quarterly 53 (2):162-169.
    In this paper, we consider a collection of filters of a BL-algebra A. We use the concept of congruence relation with respect to filters to construct a uniformity which induces a topology on A. We study the properties of this topology regarding different filters.
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  33. Strong Faithfulness and Uniform Consistency in Causal Inference.Jiji Zhang - unknown
    A fundamental question in causal inference is whether it is possible to reliably infer the manipulation effects from observational data. There are a variety of senses of asymptotic reliability in the statistical literature, among which the most commonly discussed frequentist notions are pointwise consistency and uniform consistency (see, e.g. Bickel, Doksum [2001]). Uniform consistency is in general preferred to pointwise consistency because the former allows us to control the worst case error bounds with a finite sample size. (...)
     
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  34. The Varieties of Psychedelic Epistemology.Chris Letheby - 2019 - In Nikki Wyrd, David Luke, Aimee Tollan, Cameron Adams & David King (eds.), Psychedelicacies: more food for thought from Breaking Convention.
    Recent scientific research suggests that altered states of consciousness induced by classic psychedelic drugs can cause durable psychological benefits in both healthy and patient populations. The phenomenon of ‘psychedelic transformation’ has many philosophically provocative aspects, not least of which is the claim commonly made by psychedelic subjects that their transformation is centrally due to some kind of learning or knowledge gain. Can psychedelic experiences really be a source of knowledge? From the vantage point of philosophical materialism or naturalism, a negative (...)
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  35.  38
    On varieties of biresiduation algebras.C. J. van Alten - 2006 - Studia Logica 83 (1-3):425-445.
    A biresiduation algebra is a 〈/,\,1〉-subreduct of an integral residuated lattice. These algebras arise as algebraic models of the implicational fragment of the Full Lambek Calculus with weakening. We axiomatize the quasi-variety B of biresiduation algebras using a construction for integral residuated lattices. We define a filter of a biresiduation algebra and show that the lattice of filters is isomorphic to the lattice of B-congruences and that these lattices are distributive. We give a finite basis of terms for generating (...)
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  36.  96
    Varieties of linear calculi.Sara Negri - 2002 - Journal of Philosophical Logic 31 (6):569-590.
    A uniform calculus for linear logic is presented. The calculus has the form of a natural deduction system in sequent calculus style with general introduction and elimination rules. General elimination rules are motivated through an inversion principle, the dual form of which gives the general introduction rules. By restricting all the rules to their single-succedent versions, a uniform calculus for intuitionistic linear logic is obtained. The calculus encompasses both natural deduction and sequent calculus that are obtained as special (...)
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  37.  33
    Definability properties and the congruence closure.Xavier Caicedo - 1990 - Archive for Mathematical Logic 30 (4):231-240.
    We introduce a natural class of quantifiersTh containing all monadic type quantifiers, all quantifiers for linear orders, quantifiers for isomorphism, Ramsey type quantifiers, and plenty more, showing that no sublogic ofL ωω (Th) or countably compact regular sublogic ofL ∞ω (Th), properly extendingL ωω , satisfies the uniform reduction property for quotients. As a consequence, none of these logics satisfies eitherΔ-interpolation or Beth's definability theorem when closed under relativizations. We also show the failure of both properties for any sublogic (...)
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  38.  4
    Maltsev conditions for general congruence meet-semidistributive algebras.Miroslav Olšák - 2021 - Journal of Symbolic Logic 86 (4):1432-1451.
    Meet semidistributive varieties are in a sense the last of the most important classes in universal algebra for which it is unknown whether it can be characterized by a strong Maltsev condition. We present a new, relatively simple Maltsev condition characterizing the meet-semidistributive varieties, and provide a candidate for a strong Maltsev condition.
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  39.  35
    A topology induced by uniformity on BL-algebras.Masoud Haveshki, Esfandiar Eslami & Arsham Borumand Saeid - 2007 - Mathematical Logic Quarterly 53 (2):162-169.
    In this paper, we consider a collection of filters of a BL-algebra A. We use the concept of congruence relation with respect to filters to construct a uniformity which induces a topology on A. We study the properties of this topology regarding different filters. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).
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  40.  43
    First-order indefinite and uniform neighbourhood semantics.Arnold Nat - 1979 - Studia Logica 38 (3):277 - 296.
    The main purpose of this paper is to define and study a particular variety of Montague-Scott neighborhood semantics for modal propositional logic. We call this variety the first-order neighborhood semantics because it consists of the neighborhood frames whose neighborhood operations are, in a certain sense, first-order definable. The paper consists of two parts. In Part I we begin by presenting a family of modal systems. We recall the Montague-Scott semantics and apply it to some of our systems that (...)
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  41. Varieties of anti-representationalism.Pietro Salis - 2020 - In Pedro G. Moreira (ed.), Revisiting Richard Rorty. Wilmington: Vernon Press. pp. 115-134.
    Anti-representationalism is the hallmark of Richard Rorty's critique of the epistemological tradition. According to it, knowledge does not "mirror" reality and the human mind is not a representational device. Anti-representationalism is a family of philosophical theses, respectively dealing with the notion of "representation" in different ways. Though prima facie one may feel entitled to think about anti-representationalism as a kind of uniform philosophical movement, things stand quite differently. In fact, among many anti-representationalist options, we can identify two main versions: (...)
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  42.  35
    How Does It Fit? Exploring the Congruence Between Organizations and Their Corporate Social Responsibility Activities.Menno D. T. de Jong & Mark van der Meer - 2017 - Journal of Business Ethics 143 (1):71-83.
    Several studies have focused on the effects of corporate social responsibility fit on external stakeholders’ evaluations of CSR activities, attitudes towards companies or brands, and behaviors. The results so far have been contradictory. A possible reason may be that the concept of CSR fit is more complicated than previously assumed. Researchers suggest that there may be different types of CSR fit, but so far no empirical research has focused on a typology of CSR fit. This study fills this gap, describing (...)
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  43.  21
    The Empire of Uniformity and the Government of Subject Peoples.Christine Helliwell & Barry Hindess - 2002 - Cultural Values 6 (1-2):139-152.
    James Tully's Strange Multiplicity uses the example of indigenous minorities in the white settler colonies of North America to develop a remarkably powerful critique of liberal constitutionalism's rule of uniformity. In proclaiming the identity of all persons before the law, he insists, liberal constitutional arrangements commonly discriminate against indigenous and other minorities. While the force of this critique is undeniable, it nevertheless takes at face value one of the central claims of liberal consitutionalism, namely, its claim to be based on (...)
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  44.  27
    Statement in Support of Revising the Uniform Determination of Death Act and in Opposition to a Proposed Revision.D. Alan Shewmon - 2021 - Journal of Medicine and Philosophy 48 (5):453-477.
    Discrepancies between the Uniform Determination of Death Act (UDDA) and the adult and pediatric diagnostic guidelines for brain death (BD) (the “Guidelines”) have motivated proposals to revise the UDDA. A revision proposed by Lewis, Bonnie and Pope (the RUDDA), has received particular attention, the three novelties of which would be: (1) to specify the Guidelines as the legally recognized “medical standard,” (2) to exclude hypothalamic function from the category of “brain function,” and (3) to authorize physicians to conduct an (...)
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  45.  49
    Quasi-subtractive varieties.Tomasz Kowalski, Francesco Paoli & Matthew Spinks - 2011 - Journal of Symbolic Logic 76 (4):1261-1286.
    Varieties like groups, rings, or Boolean algebras have the property that, in any of their members, the lattice of congruences is isomorphic to a lattice of more manageable objects, for example normal subgroups of groups, two-sided ideals of rings, filters (or ideals) of Boolean algebras.algebraic logic can explain these phenomena at a rather satisfactory level of generality: in every member A of a τ-regular variety ������ the lattice of congruences of A is isomorphic to the lattice of deductive filters (...)
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  46. On the Varieties of Abstract Objects.James E. Davies - 2019 - Australasian Journal of Philosophy 97 (4):809-823.
    I reconcile the spatiotemporal location of repeatable artworks and impure sets with the non-location of natural numbers despite all three being varieties of abstract objects. This is possible because, while the identity conditions for all three can be given by abstraction principles, in the former two cases spatiotemporal location is a congruence for the equivalence relation featuring in the relevant principle, whereas in the latter it is not. I then generalize this to other ‘physical’ properties like shape, mass, and (...)
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  47.  38
    Semisimplicity, EDPC and Discriminator Varieties of Bounded Weak-commutative Residuated Lattices with an S4-like Modal Operator.Hiroki Takamura - 2012 - Studia Logica 100 (6):1137-1148.
    In this paper, we show that all semisimple varieties of bounded weak-commutative residuated lattices with an S4-like modal operator are discriminator varieties. We also give a characterization of discriminator and EDPC varieties of bounded weak-commutative residuated lattices with an S4-like modal operator follows.
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  48.  5
    Institutional Transfer and Varieties of Capitalism in Transnational Societies.Carlos H. Waisman - 2011 - ProtoSociology 27:151-166.
    This paper discusses the varieties of capitalism in transitional societies in Latin America and Central / Eastern Europe. The intended purpose of these transitions from semi-closed import-substituting economies in the first case and state socialist ones in the second was to institutionalize open-market economies. Twenty or thirty years later, there is a variety of types of capitalism in these countries, which I classify into three: open-market, neo-mercantilist, and anemic. The question for sociology is whether these quite different variants represent (...)
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  49.  62
    Expansions of Semi-Heyting Algebras I: Discriminator Varieties.H. P. Sankappanavar - 2011 - Studia Logica 98 (1-2):27-81.
    This paper is a contribution toward developing a theory of expansions of semi-Heyting algebras. It grew out of an attempt to settle a conjecture we had made in 1987. Firstly, we unify and extend strikingly similar results of [ 48 ] and [ 50 ] to the (new) equational class DHMSH of dually hemimorphic semi-Heyting algebras, or to its subvariety BDQDSH of blended dual quasi-De Morgan semi-Heyting algebras, thus settling the conjecture. Secondly, we give a criterion for a unary expansion (...)
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  50.  15
    On the Variety of m-generalized Łukasiewicz Algebras of Order n.Júlia Carvalho - 2010 - Studia Logica 94 (2):291-305.
    In this paper we pursue the study of the variety $ L_n ^ m $ of m - generalized? ukasiewicz algebras of order n which was initiated in [ 1 ]. This variety contains the variety of? ukasiewicz algebras of order n. Given A? $ \ in L_n ^ m $, we establish an isomorphism from its congruence lattice to the lattice of Stone filters of a certain? ukasiewicz algebra of order n and for each (...) on A we find a description via the corresponding Stone filter. We characterize the principal congruences on A via Stone filters. In doing so, we obtain a polynomial equation which defines the principal congruences on the algebras of $ L_n ^ m $. After showing that for m > 1 and n > 2, the variety of? ukasiewicz algebras of order n is a proper subvariety of $ L_n ^ m $, we prove that $ L_n ^ m $ is a finitely generated discriminator variety and point out some consequences of this strong property, one of which is congruence permutability. (shrink)
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