Search

A graphene nano-ribbon structure can be modelled by a 3-regular hexagonal grid. We convert this to a rectangular coordinate system in order to identify uniquely the position of either the V 2 (5 - 8 - 5) double vacancy (DV) defect or the Stone–Wales SW(55–77) defect. This is done by using the lengths of the closed paths along the edges of the underlying graph. By sending a signal from one of the vertices and detecting the returning impulses one can observe experimentally the spectrum of the structure. Using the trace formula it is possible to determine the lengths of all closed paths (periodic orbits) starting and ending at the given vertex where a detector is placed. We present an algorithm which enables one to pinpoint the precise coordinates of a DV defect by using at most three reference points. Similarly we provide an algorithm for finding an SW defect. [ABSTRACT FROM AUTHOR]

We consider the bargraph representation of geometrically distributed words, which we use to define the water capacity of such words. We first find a bivariate capacity generating function for all geometrically distributed words, from which we compute the generating function for the mean capacity. Thereafter, by making extensive use of Rice's method (Rice's integrals) we derive an asymptotic formula for the average capacity of random words of length n as n tends to infinity. [ABSTRACT FROM AUTHOR]

In this paper we model a graphene nano-ribbon structure by analysing an infinite 3-regular hexagonal grid which is transformed to a rectangular coordinate system or "wall". Our goal is to solve the inverse problem of identifying the position of a single vacancy break using the lengths of the closed paths along the edges of the underlying graph. We provide an algorithm to determine the exact position of the defect by using data from at most three reference points. [ABSTRACT FROM AUTHOR]

In the United States, the number and proportion of HIV/AIDS cases among black/African Americans continue to highlight the need for new biomedical prevention interventions, including an HIV vaccine, microbicide, or new antiretroviral (ARV) prevention strategies such as pre-exposure prophylaxis (PrEP) to complement existing condom usage, harm reduction methods, and behavioral change strategies to stem the HIV epidemic. Although black/African Americans are disproportionately impacted by HIV/AIDS, their participation in HIV clinical research continues to have unique challenges. We theorize that interaction among multilevel factors creates ideal alignment for minority participation in HIV clinical studies. Thus, we initially set out to test an extended model of reasoned action with 362 participants to understand the interplay of sociopsychological and network-level considerations influencing minority participation in HIV prevention research efforts. In this study, we linked the intrapersonal dimensions of attitudes, beliefs, and normative concerns to community-level components, appraisal of involvement with the clinical research organization, an entity which operates within a networked structure of community partner agencies, and identification with coalition advocacy aims. Various participatory outcomes were explored including involvement in future HIV vaccine community functions, participation in community promotion of HIV vaccine research, and community mobilization. Three-stage least squares estimates indicated similar findings across three models. Significant effects demonstrate the importance of positive attitudes toward HIV vaccine research, favorable health research beliefs, perceived social support for participation, HIV/AIDS issue engagement, and perceived relevance of the clinical research site's mission and values. Identification of these nuanced pathway effects provides implications for tailored community program development. [ABSTRACT FROM AUTHOR]