We prove a Corona type theorem with bounds for the Sarason algebra H∞ + C and determine its spectral characteristics, thus continuing a line of research initiated by N. Nikolski. We also determine the Bass, the dense, and the topological stable ranks of H∞ + C. To fix our setting, let A be a commutative unital Banach algebra with unit e and M(A) its maximal ideal space. The following concept of...

We define some variations of the Scott rank for countable models and obtain some inequalities involving the ranks. For mono-unary algebras we prove that the game rank of any subtree does not exceed the game rank of the whole model. However, similar questions about linear orders remain unresolved.

We are interested in the kind of well-being that can occur as a person approaches death; we call it "existential maturity." We describe a conceptual model of this state that we felt was realized in an individual case, illustrating the state by describing the case. Our goal is to articulate a generalizable, working model of existential maturity in concepts and terms taken from fundamentals of ps...

This study examined concurrent influences on the will to live in 189 patients with end-stage cancer The authors found significant correlations between the will to live and existential, psychological, social, and, to a lesser degree, physical sources of distress. Existential variables proved to have the most influence, with hopelessness, burden to others, and dignity entering into the final mode...

We study conjunctive query answering and first-order rewritability of conjunctive queries for binary guarded existential rules. In particular, we prove that the problem of establishing whether a given set of binary guarded existential rules is such that all conjunctive queries admit a first-order rewriting is decidable, and present a technique for solving this problem. These results have a impo...

Closed monadic Σ1, as proposed in [AFS98], is the existential monadic second order logic where alternation between existential second order quantifiers and first order quantifiers is allowed. Despite some effort very little is known about the expressive power of this logic on finite structures. We construct a tree automaton which exactly characterizes closed monadic Σ1 on the Rabin tree and giv...

Therapeutic work with the client's present moment experience in existential therapy was studied by means of conversation analysis. Using publicly available video recordings of therapy sessions as data, an existential therapist's practice of guiding a client into immediacy, or refocusing the talk on a client's immediate experience, was described and compared with a therapist's corresponding acti...