Welfarism is the view that individual welfare is the only thing that matters. One important contribution of social choice theory has been to provide a precise formulation and axiomatic characterization of welfarism using Amartya Sen's framework of social welfare functionals. This paper is motivated by the observation that the standard formalization of welfarism is too restrictive, since a welfarist social planner need not be committed to maximizing a preference ordering or any other binary relation over alternatives. We therefore provide (...) a characterization of welfarism in a more general choice-functional setting and show that welfarism, so understood, carries no commitment to rationalizability. This characterization is compatible with welfare values having any structure whatsoever. It also sheds light on different formulations of anonymity, revealing only some of these to be fundamental requirements of impartiality. (shrink)

Philosophers have traditionally focused on the nature of scientific explanation while ignoring the process by which features of the world are formulated as discrete explanantia and explananda. However, the characterization of phenomena is an important activity in its own right, and is intertwined with evaluations of the appropriateness and sufficiency of explanatory strategies. We explore this entanglement of characterization and explanation using an extended case study from deep time: research into the Cambrian explosion. Our analysis focuses on three (...) spheres of research that together illustrate key features of characterization for complex phenomena, including open-endedness, interdisciplinarity, and a concern with explananda and explanantia alike. In addition, they suggest a pair of substantive claims: (1) characterizations of complex phenomena are frequently contested along several dimensions of descriptive understanding, and (2) the dynamics of characterization for complex phenomena are poorly described by models that treat recharacterization primarily as a response to explanatory failures. (shrink)

Hybrid languages are expansions of propositional modal languages which can refer to worlds. The use of strong hybrid languages dates back to at least [Pri67], but recent work has focussed on a more constrained system called $\mathscr{H}$. We show in detail that $\mathscr{H}$ is modally natural. We begin by studying its expressivity, and provide model theoretic characterizations and a syntactic characterization. The key result to emerge is that $\mathscr{H}$ corresponds to the fragment of first-order logic which is invariant for (...) generated submodels. We then show that $\mathscr{H}$ enjoys interpolation, provide counterexamples for its finite variable fragments, and show that weak interpolation holds for the sublanguage $\mathscr{H}$. Finally, we provide complexity results for $\mathscr{H}$ and other fragments and variants, and sharpen known undecidability results for $\mathscr{H}$. (shrink)

I provide a characterization of weakly pseudo-rationalizable choice functions---that is, choice functions rationalizable by a set of acyclic relations---in terms of hyper-relations satisfying certain properties. For those hyper-relations Nehring calls extended preference relations, the central characterizing condition is weaker than (hyper-relation) transitivity but stronger than (hyper-relation) acyclicity. Furthermore, the relevant type of hyper-relation can be represented as the intersection of a certain class of its extensions. These results generalize known, analogous results for path independent choice functions.

This article investigates the properties of multistate top revision, a dichotomous model of belief revision that is based on an underlying model of probability revision. A proposition is included in the belief set if and only if its probability is either 1 or infinitesimally close to 1. Infinitesimal probabilities are used to keep track of propositions that are currently considered to have negligible probability, so that they are available if future information makes them more plausible. Multistate top revision satisfies a (...) slightly modified version of the set of basic and supplementary AGM postulates, except the inclusion and success postulates. This result shows that hyperreal probabilities can provide us with efficient tools for overcoming the well known difficulties in combining dichotomous and probabilistic models of belief change. (shrink)

The current literature on indeterminacy centers around two projects. One concerns the logic of indeterminacy; the other concerns its nature or source. The aim of this paper is to introduce, motivate and go some way toward addressing a new, third project: that of providing what I call a minimal characterization of indeterminacy. An MC, to a first approximation, is a relatively pre-theoretical characterization of indeterminacy that is neutral between the various substantive theories of the nature and logic of (...) indeterminacy. An MC thus captures a generic sense of indeterminacy that, at least in principle, is recognized by all parties to the debate over the phenomenon’s underlying nature and logic. I begin by introducing the concept of an MC and outlining some of the main theoretical virtues of providing an MC. I then establish some desiderata on a suitable MC, and use these desiderata to rule out various initially attractive proposals. In the final part of the paper I sketch the beginnings of my own MC and defend it against objections. (shrink)

Background: Nurses must balance their perceived duty to care against their perceived risk of harm to determine their willingness to report during disaster events, potentially creating an ethical dilemma and impacting patient care. Research aim: The purpose of this study was to investigate nurses’ perceived duty to care and whether there were differences in willingness to respond during disaster events based on perceived levels of duty to care. Research design: A cross-sectional survey research design was used in this study. Participants (...) and research context: Using a convenience sample with a snowball technique, data were collected from 289 nurses throughout the United States in 2017. Participants were recruited through host university websites, Facebook, and an American Nurses Association discussion board. Ethical considerations: Institutional review board approval was obtained from the University of Texas at Tyler and the University of Arkansas. Findings: Analysis of willingness to report to work based on levels of perceived duty to care resulted in the emergence of two groups: “lower level of perceived duty to care group” and “higher level of perceived duty to care group.” The most discriminating characteristics differentiating the groups included fear of abandonment by co-workers, reporting because it is morally the right thing to, and because of imperatives within the Nursing Code of Ethics. Discussion: The number of nurses in the lower level of perceived duty to care group causes concern. It is important for nursing management to develop strategies to advance nurses’ safety, minimize nurses’ risk, and promote nurses’ knowledge to confidently work during disaster situations. Conclusion: Level of perceived duty to care affects nurses’ willingness to report to work during disasters. Primary indicators of low perceived duty to care are amenable to actionable strategies, potentially increasing nurses’ perceived duty to provide care and willingness to report to work during disasters. (shrink)

In Iemhoff we gave a countable basis for the admissible rules of . Here, we show that there is no proper superintuitionistic logic with the disjunction property for which all rules in are admissible. This shows that, relative to the disjunction property, is maximal with respect to its set of admissible rules. This characterization of is optimal in the sense that no finite subset of suffices. In fact, it is shown that for any finite subset X of , for (...) one of the proper superintuitionistic logics Dn constructed by De Jongh and Gabbay ), all the rules in X are admissible. Moreover, the logic Dn in question is even characterized by X: it is the maximal superintuitionistic logic containing Dn with the disjunction property for which all rules in X are admissible. Finally, the characterization of is proved to be effective by showing that it is effectively reducible to an effective characterization of in terms of the Kleene slash by De Jongh. (shrink)

Many philosophers working on personal identity and ethics say that personal identity is constituted by stories: narratives people tell or would tell about their lives. Most of them also say that this is personal identity in the ‘characterization sense’, that it is the notion people in ordinary contexts are interested in, and that it raises the ‘characterization question’. I argue that these claims are inconsistent. Narrativists can avoid the incompatibility in one of two ways: They can concede that (...) their view is not about the constitution but the epistemology of personal identity. Or they can say that it is not about personal identity at all. (shrink)

This paper spells out a dynamic proof format for the pure logic of relevant implication. (A proof is dynamic if a formula derived at some stage need not be derived at a later stage.) The paper illustrates three interesting points. (i) A set of properties that characterizes an inference relation on the (very natural) dynamic proof interpretation, need not characterize the same inference relation (or even any inference relation) on the usual settheoretical interpretation. (ii) A proof format may display an (...) internal dynamics (defeasible conclusions) in the absence of an external dynamics (non-monotonicity). (iii) A monotonic logic may have a non-monotonic characterization. (shrink)

In recent research, the prime and irreducible elements of strong finite factorization domains were studied. It was shown that strongly computable strong finite factorization domains (SCSFFD) have necessarily computable irreducible elements and a computable division algorithm. However, the question of how to best classify this class of structures is left unanswered. This work provides a classification for SCSFFDs by showing the existence of a computable norm where norm-form equations can be solved computably. This classification provides the intuition to extend further (...) the notion of strong computability to finite factorization domains in general. (shrink)

What is it to judge something to be a natural end? And what objects may properly be judged natural ends? These questions pose a challenge, because the predicates “natural” and “end” seemingly can not be instantiated at the same time – at least given some Kantian assumptions. My paper defends the thesis that Kant’s “Critique of Teleological Judgment”, nevertheless, provides a sensible account of judging something a natural end. On the account, a person judges an object O a natural end, (...) if she thinks that the parts of O cause O and if she is committed to approach O in a top-down manner, as if the parts were produced in view of the whole. The account is non-realist, because it involves a commitment. With the account comes a characterization that provides necessary and sufficient conditions on objects that may properly be judged natural ends. My paper reconstructs the argument in CTJ, §§64-65 where the account and the characterization are derived. (shrink)

Drought is a creeping phenomenon that slowly holds an area over time and can be continued for many years. The impacts of drought occurrences can affect communities and environments worldwide in several ways. Thus, assessment and monitoring of drought occurrences in a region are crucial for reducing its vulnerability to the negative impacts of drought. Therefore, comprehensive drought assessment techniques and methods are required to develop adaptive strategies that a region can undertake to reduce its vulnerability to drought substantially. For (...) this purpose, this study proposes a new method known as a regional comprehensive assessment of meteorological drought. The Standardized Precipitation Index, Standardized Precipitation Evapotranspiration Index, and Standardized Precipitation and Temperature Index are jointly used for the development of the RCAMD. Further, the RCAMD employs Monte Carlo feature selection and steady-state probabilities to comprehensively collect information from various stations and drought indices. Moreover, the RCAMD is validated on the six selected stations in the northern areas of Pakistan. The outcomes associated with the RCAMD provide a comprehensive regional assessment of meteorological drought and become the initial source for bringing more considerations to drought monitoring and early warning systems. (shrink)

Pyrochlore compounds have a number of technological applications, such as dielectrics for high-frequency and magnetoelectric devices. In bulk materials, they exhibit stimulated cation arrangement and good long-distance order within the pyrochlore framework. Bismuth titanate ceramics containing SiO2 and Nd2O3 were synthesized in the Bi2O3-TiO2-SiO2-Nd2O3 system using the melt-quenching method. In a previous study, the phase composition of selected samples was determined by X-ray diffraction (XRD) analysis and the microstructure was studied by scanning electron microscopy (SEM). The preparation of monophase polycrystalline (...) materials was concluded. Infrared Fourier-transformed spectroscopy (FTIR) was applied in order to identify the structure. The electrical conductivity, as well as the dielectric losses and dielectric constants of selected samples were determined, and the influence of the phase composition on the dielectric characteristics was evaluated. The combination of the pyrochlore phase with the amorphous phase represented by the structural groups Bi-O-Si and Si-O-Si exerts a grain boundary strengthening effect. (shrink)

The aim of this paper is to provide a logic-based conceptual analysis of the twin paradox (TwP) theorem within a first-order logic framework. A geometrical characterization of TwP and its variants is given. It is shown that TwP is not logically equivalent to the assumption of the slowing down of moving clocks, and the lack of TwP is not logically equivalent to the Newtonian assumption of absolute time. The logical connection between TwP and a symmetry axiom of special relativity (...) is also studied. (shrink)

Specimens of Lamellibrachia (Annelida: Siboglinidae) were recently discovered at cold seeps in the eastern Mediterranean. In this study, we have investigated the phylogeny and function of intracellular bacterial symbionts inhabiting the trophosome of specimens of Lamellibrachia sp. from the Amon mud volcano, as well as the bacterial assemblages associated with their tube. The dominant intracellular symbiont of Lamellibrachia sp. is a gammaproteobacterium closely related to other sulfide-oxidizing tubeworm symbionts. In vivo uptake experiments show that the tubeworm relies on sulfide for (...) its metabolism, and does not utilize methane. Bacterial communities associated with the tube form biofilms and occur from the anterior to the posterior end of the tube. The diversity of 16S rRNA gene phylotypes includes representatives from the same divisions previously identified from the tube of the vent species Riftia pachyptila, and others commonly found at seeps and vents. (shrink)

I consider the well-known criticism of Quine's characterization of first-order logical truth that it expands the class of logical truths beyond what is sanctioned by the model-theoretic account. Briefly, I argue that at best the criticism is shallow and can be answered with slight alterations in Quine's account. At worse the criticism is defective because, in part, it is based on a misrepresentation of Quine. This serves not only to clarify Quine's position, but also to crystallize what is and (...) what is not at issue in choosing the model-theoretic account of first-order logical truth over one in terms of substitutions. I conclude by highlighting the need for justifying the belief that the definition of first-order logical truth in terms of models is superior to its definition in terms of substitutions. (shrink)

Inductively defined structures are ubiquitous in mathematics; their specification is unambiguous and their properties are powerful. All fields of mathematical logic feature these structures prominently: the formula of a language, the set of theorems, the natural numbers, the primitive recursive functions, the constructive number classes and segments of the cumulative hierarchy of sets. -/- This dissertation gives a mathematical characterization of a species of inductively defined structures, called accessible domains, which include all of the above examples except the set (...) of theorems. The concept of an accessible domain comes from Wilfried Sieg's analysis of proof-theoretic practices, starting with his dissertation. In particular, he noticed the special epistemological character of elements of an accessible domain: they can always be uniquely identified with their build-up. Generally, the unique build-up of elements justifies the principles of induction and recursion. -/- I use category theory to give an abstract characterization of accessible domains. I claim that accessible domains are all instances of initial algebras for endofunctors. Grounded in the historical roots of Sieg's discussions, this dissertation shows how the properties of initial algebras for endofunctors and accessible domains coincide in a satisfying and natural way. -/- Filling out this characterization, I show how important examples of accessible domains fit into this broad characterization. I first characterize some accessible domains by relatively simple functors (e.g. finite, polynomial, those that preserve certain colimits) where we can see how iterating the functor can produce the accessible domain. Then I describe accessible domains that result from more involved specifications (e.g. ordinals and segments of the cumulative hierarchies associated with CZF, IZF, and ZF) by relying heavily on algebraic set theory. I end with a discussion of some of the methodological features of category theory in particular that helped characterize accessible domains. (shrink)

In this article we provide an intrinsic characterization of the famous Howard–Bachmann ordinal in terms of a natural well-partial-ordering by showing that this ordinal can be realized as a maximal order type of a class of generalized trees with respect to a homeomorphic embeddability relation. We use our calculations to draw some conclusions about some corresponding subsystems of second order arithmetic. All these subsystems deal with versions of light-face Π11\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varPi ^1_1$$\end{document}-comprehension.

This document describes the technique and technology currently used to apply cryosurgery, a technic based on low temperatures for medical purposes that allows the controlled destruction of pathological cells and tissues. Cryosurgery is an effective and innocuous process that is painless, safe and economical, applied to multiple specialities in which it provides alternatives to its traditional methods. A search was carried out for articles and bibliographic reviews referring to Cryosurgery and from whose information this technical note was obtained. Research on (...) the application of Cryosurgery presents solid evidence of its benefits. Therefore, it has been used in several countries and health campaigns, showing excellent results, so it is advisable to implement it in health systems. (shrink)

A geometric lattice is the lattice of closed subsets of a closure operator on a set which is zero-closure, algebraic, atomistic and which has the so-called exchange property. There are many profound results about this type of lattices, the most recent one of which, due to Czédli and Schimdt, says that a lattice L of finite length is semimodular if and only if L has a cover-preserving embedding into a geometric lattice G of the same length. The goal of our (...) paper is to offer the following result: a lattice of finite length is semimodular if and only if every cell in L is a 4-element Boolean lattice and the 7-element non-distributive atomistic lattice having 3 atoms is not a cover-preserving sublattice of L. (shrink)

In the paper we investigate Birkhoff’s conditions and. We prove that a discrete lattice L satisfies the condition ) if and only if L is a 4-cell lattice not containing a cover-preserving sublattice isomorphic to the lattice S*7. As a corollary we obtain a well known result of J. Jakub´ık from [6]. Furthermore, lattices S7 and S*7 are considered as so-called partially cover-preserving sublattices of a given lattice L, S7 ≪ L and S7 ≪ L, in symbols. It is shown (...) that an upper continuous lattice L satisfies if and only if L is a 4-cell lattice such that S7 ≪/ L. The final corollary is a generalization of Jakubík’s theorem for upper continuous and strongly atomic lattices. Keywords: Birkhoff’s conditions, semimodularity conditions, modular lattice, discrete lattices, upper continuous lattice, strongly atomic lattice, cover-preserving sublattice, cell, 4-cell lattice. (shrink)