2,859 research outputs found
Triangle-Free Triangulations, Hyperplane Arrangements and Shifted Tableaux
Flips of diagonals in colored triangle-free triangulations of a convex
polygon are interpreted as moves between two adjacent chambers in a certain
graphic hyperplane arrangement. Properties of geodesics in the associated flip
graph are deduced. In particular, it is shown that: (1) every diagonal is
flipped exactly once in a geodesic between distinguished pairs of antipodes;
(2) the number of geodesics between these antipodes is equal to twice the
number of Young tableaux of a truncated shifted staircase shape.Comment: figure added, plus several minor change
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The Diabetic Dog as a Translational Model for Human Islet Transplantation.
The dog model has served as the primary method for early development of many diabetes therapies, including pancreatic islet transplantation techniques and immunosuppressive protocols. Recent trends towards the use of monoclonal antibody therapies for immunosuppression in human islet transplantation have led to the increasing use of primate models with induced diabetes. In addition to induced-disease models in large animals, scientists in many fields are considering the use of naturally-occurring disease models in client-owned pets. This article will review the applicability of naturally-occurring diabetes in dogs as a translational model for developing islet transplantation in the human diabetic patient
Flag weak order on wreath products
A generating set for the wreath product \ZZ_r \wr S_n which leads to a
nicely behaved weak order is presented, and properties of the resulting order
are studied.Comment: 20 pages, 2 figures; corrected and added proofs and explanation
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Do Not Speak about Love. Speak about Compassion.
First, let me say one or two things about the word love. Love is such a used, abused, and misused word that people should possibly stay away from it. We use it for all kinds of purposes, to contain all kinds of meanings. Most of them are completely disconnected and unimportant. The word is especially abused in the English language, where you have love and divine love and "whatever" love. You have also the phrase making love, which is not exactly like love, but at least has a veiy clear-cut meaning. We should use other words for this, in order not be confused and mistaken. Today, we will look at the concept of love in international affairs and love in the university. The very combinations seem somehow impossible, or perhaps too ugly, to contemplate. Having discussed the problems with the word love, let me say a few words about how I would define it. I am not going to try to make a comprehensive definition—it's too complex and too hard. But to make a definition that has a clear meaning, clear enough to comprehend in itself, and to set borders and limits, let us say that— in essence—love is the basic experience of a feeling for the Other. In its simplest form, it is the motion of going out from myself toward the Other. That is the essence of love, and therefore any other meaning you give the word is marring it, obscuring it or making fraudulent claims
On Degrees in the Hasse Diagram of the Strong Bruhat Order
For a permutation in the symmetric group let the {\it total
degree} be its valency in the Hasse diagram of the strong Bruhat order on
, and let the {\it down degree} be the number of permutations which are
covered by in the strong Bruhat order. The maxima of the total degree and
the down degree and their values at a random permutation are computed. Proofs
involve variants of a classical theorem of Tur\'an from extremal graph theory.Comment: 14 pages, minor corrections; to appear in S\'em. Lothar. Combi
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