Let R be an associative ring with identity. It is shown that every Σ -cotorsion left R-module satisfies the descending chain condition on divisibility formulae. If R is countable, the descending chain condition on M implies that it must be Σ -cotorsion. It follows that, for countable R, the class of Σ -cotorsion modules is closed under elementary equivalence and pure submodules. The modules M t...

In undergoing this life, many people always try to do and get the best. New knowledge, experience, lesson, and everything that can improve the life will be done. However, many people sometimes feel confused to get those things. Feeling the limited of experience and sources to be better is one of the lacks to own. However, there is a very simple thing that can be done. This is what your teacher ...

In this paper we present and compare two interpretations of classical logic proofs in a category of posets and relations, and relate their behavior to proof nets, extracting meaningful invariants of proofs. We show that at least one of these interpretation cannot have anything to do with the Curry-Howard correspondence.

We study the asymptotic geometry of Teichmüller geodesic rays. We show that when the transverse measures to the vertical foliations of the quadratic differentials determining two different rays are topologically equivalent, but are not absolutely continuous with respect to each other, then the rays diverge in Teichmüller space.

What’s the best thing about HHMI funding? There's lots of it. The annual HHMI budget was $330 million in 1994, of which about 80 % was spent on the 227 HHMI investigators. For those who need lots of money for mice or equipment, HHMI funding can be the answer to a prayer. And HHMI, unlike most other funding bodies, does not discourage long-term, risky research or projects with little obvious rel...

It is a well known fact that there is a correspondence between propositions and type, and similarly a correspondence between a proof of a proposition and a program of a type; this is the Curry-Howard correspondence. In this talk I will describe a program, Djinn, which takes a Haskell type and produces a program of that type, using the Curry-Howard correspondence. For the subset of Haskell types...

In a previous report we have described an apparent increase in cellular permeability which begins within a matter of seconds after the irreversible at tachment of T1 or T2 bacteriophages to their host cell (1), and have suggested that it may be a reflection of a lyric process initiated by the virus in the cell wall, in the course of penetration of the virus desoxyfibonucleie acid (DNA) (2, 3, 1...

While 4D models (3D plus time) are becoming more prevalent in design and construction, the characteristics and use of these tools is still being explored. Research at CIFE(Center for Integrated Facility Engineering) is focusing on the usability of the models not only in terms of their visual and communicative impact but impact on the construction design process. We are developing a 4D-CAD tool ...