Making Non-Associative Algebra Associative

Based on results about open string correlation functions, a nonassociative algebra was proposed in a recent paper for D-branes in a background with nonvanishing $H$. We show that our associative algebra obtained by quantizing the endpoints of an open string in an earlier work can also be used to reproduce the same correlation functions. The novelty of this algebra is that functions on the D-brane do not form a closed algebra. This poses a problem to define gauge transformations on such noncommutative spaces. We propose a resolution by generalizing the description of gauge transformations which naturally involves global symmetries. This can be understood in the context of matrix theory.Comment: 12 pages, Latex, acknowledgement adde

Nambu Bracket for M Theory

In this article we give a concise review of recent progress in our understanding of the Lie 3-algebra and their application to the Bagger-Lambert-Gustavsson model describing multiple M2-branes in M theory.Comment: 13 pages, prepared for The Fourth International Symposium on Symmetries in Subatomic Physics (SSP 2009), minor modification, references adde

Comment on Self-Consistent Model of Black Hole Formation and Evaporation

In an earlier work, Kawai et al proposed a model of black-hole formation and evaporation, in which the geometry of a collapsing shell of null dust is studied, including consistently the back reaction of its Hawking radiation. In this note, we illuminate the implications of their work, focusing on the resolution of the information loss paradox and the problem of the firewall.Comment: 16 pages, 6 figures, references adde

Evidence-Based Study of Medication Compliance Project in Hiv Prevention Using Pre-Exposure Prophylaxis (Prep) Antivirals for HIV-Negative Males

In 2012, emtricitabine/tenofovir was the only Food and Drug Administration-approved medication for pre-exposure prophylaxis (PrEP) used in human immunodeficiency virus (HIV) prevention. To date, there is little research on open-label and mixed-payer characteristics supporting medication compliance of men who have sex with men (MSM). The purpose of this research was to describe individual demographic variables associated with PrEP medication adherence and to examine the effect of a follow-up phone call from a nurse once a month for 3 months. A total of 30 MSM were recruited and data were collected using a demographic questionnaire, medication adherence tool and follow-up phone calls. Data were analyzed using a statistical package. Spearman’s rho correlations demonstrated high medication adherence in single men (rs (28) = −.375, p \u3c .05) with no mental health issues (rs (28) = .426, p \u3c .05) and a higher educational level (rs (28) = −.431, p \u3c .05). A between group Chi-square demonstrated men with high medication adherence and medium medication adherence did not statistically differ over 3 months (χ2 (2, N = 28) = .668, p = .71). Individuals who exhibited higher PrEP use in an open-label and mixed-payer structure appeared to be young, single, well educated, and employed Caucasian gay males with multiple partners. More information will be needed from ethnically diverse populations, especially non-Caucasians. Finally, clinical nurses, by supplying accountability by phone calls, could improve PrEP compliance by providing planned monthly reminders

The Absence of Horizon in Black-Hole Formation

With the back-reaction of Hawking radiation taken into consideration, the work of Kawai, Matsuo and Yokokura has shown that, under a few assumptions, the collapse of matter does not lead to event horizon nor apparent horizon. In this paper, we relax their assumptions and elaborate on the space-time geometry of a generic collapsing body with spherical symmetry. The geometry outside the collapsing sphere is found to be approximated by the geometry outside the white-hole horizon, hence the collapsing matter remains outside the Schwarzschild radius. As particles in Hawking radiation are created in the vicinity of the collapsing matter, the information loss paradox is alleviated. Assuming that the collapsing body evaporates within finite time, there is no event horizon.Comment: 28 pages, minor modificatio

Pressure measurements of impinging jet with asymmetric nozzle

For modern aircraft, impinging surfaces are commonly used as a device for obtaining vector thrust from engine exhaust. The nature of dynamic loading is important to understand for design purposes. In this study, the frequency, mode, and level of pressure fluctuations generated by an elliptic jet are examined. The elliptic jet is used because it has several operational advantages over a circular jet