Lecture on Ulcers

Report on Tropical Ulcers

Studies on Phagedenic Ulcers *

Since the days of Hippocrates6 the terms phagedena, phagedenic ulceration, and phagedenism have been applied to "corrosive" ulcers which became "spreading and inveterate." With a few exceptions, the early writings on the subject are limited to the consideration of phagedena as the sequel of chancre or chancroid. In 1879 Gosselin5 and Fournier4 independently emphasized the fact that phagedena wa...

Lecture Notes on Sorting

We begin this lecture by discussing how to compare running times of functions in an abstract, mathematical way. The same underlying mathematics can be used for other purposes, like comparing memory consumption or the amount of parellism permitted by an algorithm. We then use this to take a first look at sorting algorithms, of which there are many. In this lecture it will be selection sort becau...

Lecture Notes on Surfaces

1. Surfaces Intuitively, a surface is a subset of R3 that “looks like” a plane when you zoom in on it, in the same way that the graph of a smooth function looks like a line when you zoom in on it. Surfaces are more complex objects than curves, and to appropriately describe them we will require a more complex definition than we had for curves. In this section we will gradually build the definiti...

Lecture Notes on Quicksort

In this lecture we consider two related algorithms for sorting that achieve a much better running time than the selection sort from last lecture: mergesort and quicksort. We developed quicksort and its invariants in detail. As usual, contracts and loop invariants will bridge the gap between the abstract idea of the algorithm and its implementation. We will revisit many of the computational thin...