Experimental determination of the elastic modulus and ultimate strength of human tibial trabecular bone as a function of metaphyseal location is presented. A 1 cm cubic matrix with planes parallel to the subchondral plate was defined on five fresh frozen cadaver tibias. Approximately 400, 7 mm X 10 mm cylindrical bone plugs were cut from the locations defined by the matrix and tested in uniaxial compressive stress at a strain rate of 0.1%S-1. Results of the study indicate that the trabecular bone properties vary as much as two orders of magnitude from one location to another. As might be predicted from Wolff's law, and noted by previous investigators, concentrations of strength arise from the medial and lateral metaphyseal cortices toward the major medial and lateral contact regions. These results may be valuable for improved analytical modeling and optimal prosthetic design.

The constitutive equation for large elastic deformations is often used to model the mechanical response of soft tissue. This paper is concerned with the applications of the method of material identification to the determination of the strain energy density functions (W) in such a mode, under the assumption that the tissue is incompressible and isotropic. It is shown that an identification experiment based on inflation by lateral pressure ofan initially flat circular membraneous specimen has a number of advantages. These are: the method of clamping the specimen, the ease of labelling material particles and measuring current coordinates, the easily determined domain of identification of I% and a means of systematically determining Wover a large deformation range. An example in the form of a hypothetical experiment is presented.

This article describes a qualitative evaluation of the Seniors Active Living in Vulnerable Elders (ALIVE) program, a 10-month health promotion program for low income seniors. Program interventions delivered in seniors' apartment buildings included exercise classes, health information sessions (i.e., health corners), and newsletters. The evaluation examined program participation, program impacts, and how the program worked. The most frequent reason for joining the program was recognizing the benefits of exercise, and the most frequent reason for not attending the program was having other priorities. The main participant impact was "feeling better." Specific impacts were also noted in physical, mental, and social domains. Fun, program delivery adaptations, autonomy, social interactions, and staff-participant relationships were discovered to be important program processes. These processes all contributed to participant's "comfort" in the program. How and why the program worked is examined in relation to Pender's (1996) revised health promotion model and implications for nursing are indicated.

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