Probing the Two-Temperature Paradigm: Observational Tests for the Basic Assumptions in ADAFs

We calculate the flux and spectrum of synchrotron radiation produced by high energy electrons and positrons (\epm) in an advection dominated accretion flow (ADAF) around a black hole. The \epm are from the decay of charged pions which are created through proton-proton collisions. We consider both a thermal and power-law energy distribution of protons, and show that the resulting \epm synchrotron emission produces a characteristic spectrum between radio and X-ray frequencies. While previous signatures of the hot protons were only possible at gamma-ray energies, via the production of gamma-rays through neutral pion decay, the present results provide a more observationally tractable way of probing the proton energy distribution and the two temperature structure in these accretion flows. We discuss a number of strong observational predictions from these systems, as well as the recent results of Mahadevan (1998) which appear to confirm the two temperature structure in ADAFs. We show that the results provide support for both a power-law and thermal distribution of protons, with at least a third of the viscous energy going into the power-law.Comment: Submitted to MNRAS. 27 pages including 5 figure

Matroids with a modular 4-point line

A result of Seymour implies that any 3-connected matroid with a modular 3-point line is binary. We prove a similar characterization for 3-connected matroids with modular 4-point lines. We show that such a matroid is either representable over GF(3) or GF(4) or has an $F_7$-minor and either an $(F_7^-)$- or $(F_7^-)^*$-minor.Comment: 26 page

The Role of Cultural Competency on Treatment Adherence and Health Literacy for Persons of Color Living with HIV/AIDS

The Role of Cultural Competency on Treatment Adherence and Health Literacy for Persons of Color Living with HIV/AIDS Rohan Arora, Depts. of Psychology, Medical Humanities, & Chemistry, with Dr. Faye Pritchard, VCU Honors College For decades, the American medical establishment has been a notable perpetrator in the mass marginalization of minority groups, leading to a variety of health disparities. Given that the existing healthcare institution is not culturally equipped to serve the evolving American demographic, experts have called for the greater usage of cultural competency in medicine; however, little research has been done to better understand how the degree of cultural competency of a health-care provider impacts the complex disease management for those living with HIV/AIDS. The aim of this research is to better understand how cultural competency can impact the health literacy and treatment adherence for persons of color living with HIV/AIDS. In addition to considering what factors shape patient experience and expectations, the research explores how many socioeconomic and cultural factors lead to low treatment adherence and health literacy. Also, the research considers the nuance in the patient-provider relationship and explores tools, such as partnerships with existing community institutions, that may strengthen the relationship. In order to regain the trust lost in the medical establishment by persons of color living with HIV/AIDS, the research suggests that a healthcare provider ought to self-reflect about the cultural, linguistic, and socioeconomic complexities in America that necessitate cultural competency. By practicing modernized cultural competency in medicine, healthcare providers can shape patient care and strengthen the patient-provider relationship, which may increase treatment adherence and health literacy rates for persons of color living with HIV/AIDS. Bringing attention to how cultural competency can impact treatment adherence and health literacy, the research urges the medical establishment to take educational and policy-related steps to effectively provide healthcare to historically underserved groups such as people of color living with HIV/AIDS.https://scholarscompass.vcu.edu/uresposters/1353/thumbnail.jp