Model Structures on Exact Categories

We define model structures on exact categories which we call exact model structures. We look at the relationship between these model structures and cotorsion pairs on the exact category. In particular, when the underlying category is weakly idempotent complete we get Hovey's one-to-one correspondence between model structures and complete cotorsion pairs. We classify the right and left homotopy relation in terms of the cotorsion pairs and look at examples of exact model structures. In particular, we see that given any hereditary abelian model category, the full subcategories of cofibrant, fibrant and cofibrant-fibrant subobjects each have natural exact model structures equivalent to the original model structure. These model structures each have interesting characteristics. For example, the cofibrant-fibrant subobjects form a Frobenius category whose stable category is the same thing as the homotopy category of its model structure.Comment: 17 page

An introduction to ethical consideration in international environmental law

The purpose of this chapter is to give the reader an overview of where some of the ethical debates in international environmental law are currently found. This chapter builds upon my earlier work in this area, which is contained in “International Environmental Law, Policy and Ethics”

Grammar Jam: Adding a Creative Editing Tactic

The author argues reading, hearing, and then composing musical lyrics involving grammatical concerns can help college writing students to edit more effectively for a song\u27s grammar topic. Explaining that the songs need to offer specific advice, such as how to both spot and correct the grammatical problem, the writer offers lyrical examples and provides scholarly evidence for this approach. The essay explains what Grammar Jam is, why music can work, and how to use the tactic in the classroom