We propose a notion of groupoid homotopy for generalized maps. This notion of groupoid homotopy generalizes the notions of natural transformation and strict homotopy for functors. The groupoid homotopy type of a Lie groupoid is shown to be invariant under Morita equivalence. As an application we consider orbifolds as groupoids and study the orbifold homotopy between orbifold maps induced by the...

–The objective of this work is to study the performance of a split air conditioning system with and without a Matrix Heat Exchanger (MHE) .The experiment was done using HFC134a as the refrigerant and Polyol-ester oil (POE) as the conventional lubricant in the air conditioning system. The performance of the split air conditioning system with HFC134a/POE oil system was compared with HFC134a/POE o...

OBJECTIVE Direct physician order entry (POE) offers many potential benefits, but evidence suggests that POE requires substantially more time than traditional paper-based ordering methods. The Medical Gopher is a well-accepted system for direct POE that has been in use for more than 15 years. The authors hypothesized that physicians using the Gopher would not spend any more time writing orders t...

Genetic imprinting is the most well-known cause for parent-of-origin effect (POE) whereby a gene is differentially expressed depending on the parental origin of the same alleles. Genetic imprinting is related to several human disorders, including diabetes, breast cancer, alcoholism, and obesity. This phenomenon has been shown to be important for normal embryonic development in mammals. Traditio...

The progress of studies by this team of researchers concerning computerized physician order entry (POE), beginning with a mail survey and moving to qualitative multi-center studies, is reviewed, with emphases on lessons learned and future directions. While mail surveys were appropriate to answer initial research questions about diffusion of POE in the U.S., multiple qualitative methods became t...

The notion of Cayley color graphs of groups is generalized to inverse semigroups and groupoids. The set of partial automorphisms of the Cayley color graph of an inverse semigroup or a groupoid is isomorphic to the original inverse semigroup or groupoid. The groupoid of color permuting partial automorphisms of the Cayley color graph of a transitive groupoid is isomorphic to the original groupoid.

In this paper, we introduce the notion of a logistic groupoid on the real numbers R, and show that, given a groupoid (R, ?) with some conditions, there exists a groupoid (X, ~) such that (R, ?) is the logistic groupoid of (X, ~).