The asymptotic dimension of a curve graph is finite

We find an upper bound for the asymptotic dimension of a hyperbolic metric space with a set of geodesics satisfying a certain boundedness condition studied by Bowditch. The primary example is a collection of tight geodesics on the curve graph of a compact orientable surface. We use this to conclude that a curve graph has finite asymptotic dimension. It follows then that a curve graph has property $A_1$. We also compute the asymptotic dimension of mapping class groups of orientable surfaces with genus $\le 2$.Comment: 19 pages. Made some minor revisions. The section on mapping class groups has been rewritten; in particular we compute the asdim of Mod(S) where S has genus at most 2. The last section on open questions has been modified to reflect recent developments. References have been update

On constructions preserving the asymptotic topology of metric spaces

We prove that graph products constructed over infinite graphs with bounded clique number preserve finite asymptotic dimension. We also study the extent to which Dranishnikov's property C, and Dranishnikov and Zarichnyi's straight finite decomposition complexity are preserved by constructions such as unions, free products, and group extensions.Comment: 13 pages, accepted for publication in NC Journal of Mathematics and Statistic

How Educators Can Eradicate Disparities in School Discipline: A Briefing Paper on School-Based Interventions

The number of students issued suspensions in U.S. schools continues to be extremely high, resulting in thousands of students missing school every day. Simultaneously,disparities in school suspension continue to worsen, indicating that students in some groups are missing school far more often and disproportionately(particularly, boys, African American students, students with disabilities, and in some regions, Latino and American Indian students). These disparities are also true of referrals to law enforcement and school-based arrests nationwide. According to recent data collected by the Department of Education's Office for Civil Rights, students of color made up 75% of referrals to law enforcement and 79% of schoolbased arrests, even while students of color comprise 39% of the nation's public school population.Punitive school discipline matters tremendously to the educational opportunity of young people: New knowledge on school discipline shows that even a single suspension or a single referral to the juvenile court system increases the odds of low achievement and dropping out of school altogether. Moreover, research shows that schools and educators -- not just students themselves -- make a difference in how discipline is meted out

Simulation of an open-loop stepping motor system

This report presents a description and functional model of a hybrid stepping motor drive system. The motor drive methods of fullstepping and backstepping are presented as examples. Test methods for system characterization are described, and response characteristics for the simulated and experimental results are compared to verify the model. This paper shows that an open-loop stepping motor drive system can be accurately simulated to predict real hardware performance

John Donne: Love and Voices in the Elegies and Songs and Sonnets.

This thesis argues that Donne's Elegies and Songs and Sonnets found a readership trained to appreciate his words. It draws on the work of Wolfgang Iser. Iser particularly looks at the importance of a text providing a space in which the reader can imagine possibilities that extend his or her world. It is through voices that Donne connects with his readers, and creates worlds and spaces that they can explore. As his poetic control matures, Donne increasingly lives inside the poetic worlds he creates. At first, in the Elegies, his speaker is the societal observer and participant. Through this speaker, Donne will increasingly seek to educate his readers, and have them imagine new ways to approach life and love. In the Elegies, women will be the touchstone against which men measure their worth. In the Songs and Sonnets the speaker develops to be Donne himself, and the measure of worth will change to be the prospect of an androgynous, balanced, constant love. Donne explores the nature of what such a reciprocal love might look like, pushes rhetoric almost to breaking point, and seeks poetic solutions to the questions a challenging world poses. It is Donne's developing awareness of the power of voice that allows him to structure his world, finally face the agonizing loss of Anne, and contemplate a life with God. An awareness of biographical context will at times help to more fully understand his poetry. And it is voices, both real and imagined, that offer the reader the chance to participate in making meaning in that poetry

In Defense of Colonel Richard P. Roberts, Commanding Officer of the Pennsylvania 140th Regiment

Richard P. Roberts was the colonel of the Pennsylvania 140th regiment from its organization in September 1862 until his death at Gettysburg in July 1863. During this time period, Captain David Acheson of Company C fostered a “growing dislike” for the colonel that led him to portray the colonel negatively in his writings. Unfortunately for the colonel’s reputation, Acheson’s letters have been widely published, leading at least one historian to accept Acheson’s poor opinion of the colonel as fact. However, other primary sources exist which collectively demonstrate a positive regimental opinion of the colonel and further suggest that Acheson’s criticisms of the colonel were largely unwarranted and were a product of his own biases instead of an honest appraisal of the colonel’s performance. In fact, Colonel Roberts performed his duties admirably and is worthy of a commendation that, until now, the Acheson letters have largely denied him