Product Integrals and Wilson loops

Using product integrals we review the unambiguous mathematical representation of Wilson line and Wilson loop operators, including their behavior under gauge transformations and the non-abelian Stokes theorem. Interesting consistency conditions among Wilson lines are also presented.Comment: 3 pages LaTeX. Write-up of talk at DPF2000, Columbus, OH, August 11, 200

Derived autoequivalences and a weighted Beilinson resolution

Given a smooth stacky Calabi-Yau hypersurface X in a weighted projective space, we consider the functor G which is the composition of the following two autoequivalences of D^b(X): the first one is induced by the spherical object O_X, while the second one is tensoring with O_X(1). The main result of the paper is that the composition of G with itself w times, where w is the sum of the weights of the weighted projective space, is isomorphic to the autoequivalence "shift by 2". The proof also involves the construction of a Beilinson type resolution of the diagonal for weighted projective spaces, viewed as smooth stacks.Comment: 19 pages; minor modifications; accepted by J. Geom. Phy

LIFETIME LEVERAGE CHOICE FOR PROPRIETARY FARMERS IN A DYNAMIC STOCHASTIC ENVIRONMENT

This article reviews various models that may be used to explain optimal leverage choice for the proprietary farmer in a stochastic dynamic environment and develops a new model that highlights the risk of failure rather than the usual concept of risk as the variability of wealth. The model suggests that in addition to the usual factors, farm financial leverage is affected by age, wealth, and the opportunity cost of farming.Farm Management,

Type IIB orientifolds with discrete torsion

We consider compact four-dimensional ${\bf Z_N}\times {\bf Z_M}$ type IIB orientifolds, for certain values of $N$ and $M$. We allow the additional feature of discrete torsion and discuss the modification of the consistency conditions arising from tadpole cancellation. We point out the differences between the cases with and without discrete torsion.Comment: 4 pages LaTeX. Write-up of talk at DPF2000, Columbus, OH, August 10, 2000. References adde

Student Perceptions and Grade Comparisons after Exposure to Instructor-Made Skills Videos in a Kinesiology Course

The purpose of this mixed method, descriptive case study was to determine whether the use of pre-recorded instructor-made videos (PRIMVs) in a kinesiology course, along with curricular design changes, facilitated increased conceptual and practical student learning. The study examined three student cohorts in one occupational therapy program. Two of the student cohorts had unrestricted access to the PRIMVs designed to support student learning of bone and muscle palpation and joint actions. Students from the two cohorts completed a survey about their experience of having access to the videos. Exam data from the student cohorts who had access to the videos was compared to exam data from an earlier cohort who had not been exposed to the videos. While no significant differences in the lab exam grades were noted, quantitative and qualitative data collected from the surveys revealed that students perceived that their overall course grade was higher and they were better prepared for clinical fieldwork as a result of having access to the videos. This study adds to the growing body of evidence that supports video technology as a supplemental learning tool in occupational therapy education