Physical Models of Tissue in Shear Fields11This article is dedicated to our friend and colleague, Robert C. Waag.

AbstractThis review considers three general classes of physical as opposed to phenomenological models of the shear elasticity of tissues. The first is simple viscoelasticity. This model has a special role in elastography because it is the language in which experimental and clinical data are communicated. The second class of models involves acoustic relaxation, in which the medium contains inner time-dependent systems that are driven through the external bulk medium. Hysteresis, the phenomenon characterizing the third class of models, involves losses that are related to strain rather than time rate of change of strain. In contrast to the vast efforts given to tissue characterization through their bulk moduli over the last half-century, similar research using low-frequency shear data is in its infancy. Rather than a neat summary of existing facts, this essay is a framework for hypothesis generation—guessing what physical mechanisms give tissues their shear properties

A Survey of Team Teaching Effectiveness in Executive Graduate Business Programs

This paper contributes to the academic literature by using a survey instrument of executive students to assess the effectiveness of team teaching in a multidisciplinary Executive MBA management program and an Executive Master’s program in Finance. The cohort structure of the program and the virtual similarities between the two programs allows for a unique way of addressing this issue. The results of the survey show that the multidisciplinary EMBA program was more effective in fostering an integrated team teaching approach. The results also suggest that there is a transition process in incorporating the team teaching approach in new programs as evidenced by the results in the Executive Master’s Program in Finance

The democratizing potential of the Internet in Southeast Asia

This thesis argues that the Internet is likely to he a strong, positive facilitating factor for the transition to and consolidation of democracy for states in Southeast Asia. U.S. policy makers intent on promoting democracy in Southeast Asia should consider the Internet's potential as a tool for promoting democratization. A review of the existing democratization literature, coupled with quantitative analysis of the societal impact of computer networking technologies, suggests that the level of Internet connectivity is a powerful indicator of democratization. Compared to education and income, Internet connectivity provides greater statistical explanatory power in predicting democracy. The Internet experience in Indonesia and Malaysia, two Southeast Asian states ruled by non%democratic authoritarian regimes, supports this argument. internet expansion in both states has co-varied with increasing levels of political liberalization and this may enhance the prospects for democratic transition. Both states have abandoned strict controls on press freedom and free speech on the internet. A democracy assistance program designed to increase the level of internet connectivity in Southeast Asia may serve the purpose of promoting democracy while also advancing U.S. economic interests. Such a program may he viewed with less suspicion and as more politically neutral than traditional forms of democracy assistancehttp://archive.org/details/thedemocratizing109458204Lieutenant, United States Nav

Reverberant Elastography for the Elastic Characterization of Anisotropic Tissues

We derive closed-form solutions for reverberant elastography in anisotropic elastic media by adapting the framework used in electromagnetic theory to treat transverse isotropic materials. Different sample-setup geometries are analyzed, highlighting their relevance for both optical coherence elastography (OCE) and ultrasound elastography (USE). Numerical simulations using finite elements are used to validate the proposed solutions in practical cases. OCE experiments are conducted in ex vivo chicken muscle samples for the characterization of in-plane and out-of-plane shear modulus assuming a transverse isotropic elastic model. Additionally, we obtained a generalized geometry-independent solution for the isotropic media case, thus unifying previous results for reverberant elastography.Comment: 12 pages, 14 figure