Development and implementation of a custom program for post hoc strain tracking in biological specimens using cross-correlation - biomed 2011.

The research presented describes the development of a custom MATLAB® program designed to examine changes in surface strain based on digital image tracking, a technique that employs markerless tracking to access regional displacement in digital images. Strain tracking is accomplished through the analysis of successive images taken during testing using a dedicated black and white camera incorporated into a tensile testing system. In the tracking program a 2-D array of grid points is mapped on the initial image from a test.

Geometric morphometric analyses of hominid proximal femora: taxonomic and phylogenetic considerations.

The proximal femur has long been used to distinguish fossil hominin taxa. Specifically, the genus Homo is said to be characterized by larger femoral heads, shorter femoral necks, and more lateral flare of the greater trochanter than are members of the genera Australopithecus or Paranthropus. Here, a digitizing arm was used to collect landmark data on recent human (n=82), chimpanzee (n=16), and gorilla (n=20) femora and casts of six fossil hominin femora in order to test whether one can discriminate extant and fossil hominid (sensu lato) femora into different taxa using three-dimensional (3D) geometric morphometric analyses.

Operating curves to characterize the contraction of fibroblast-seeded collagen gel/collagen fiber composite biomaterials: effect of fiber mass.

Background: Collagen is a well-established and important biomaterial that could be used to help meet significant medical needs for various soft-tissue replacements. Many efforts to create engineered soft-tissue constructs by seeding cells within collagen gels have been hampered because constituent cells contract collagen gels over time, resulting in a construct that is only a fraction of the original size and that contains a cell population that has suffered a large degree of cell death. However, the presence of embedded short collagen fibers has been shown to significantly limit contraction and dramatically enhance permeability in fibroblast-seeded collagen gels.

Collagen composite biomaterials resist contraction while allowing development of adipocytic soft tissue in vitro.

Soft tissue defects resulting from tumor resection or trauma require surgery to restore the body's contours. Because autologous tissues or synthetic implant reconstructions can be less than ideal, engineered tissues produced in vitro are being developed as alternatives. Collagen gels have been proposed for this application because they are biocompatible and can be shaped to fill a specific defect.

Development of ligament-like structural organization and properties in cell-seeded collagen scaffolds in vitro.

Acute anterior cruciate ligament (ACL) injuries lead to poor joint function, instability, and eventually osteoarthritis if left untreated. Current surgical treatment options are not ideal; however, tissue engineering may provide mechanically sound, biocompatible reconstructions. Collagen fiber scaffolds were combined with fibroblast-seeded collagen gels and maintained in culture for up to 20 days.

Peak torque and rotational stiffness developed at the shoe-surface interface: the effect of shoe type and playing surface.

Background: Shoe-surface interactions have been implicated in the high number of noncontact knee injuries suffered by athletes at all levels.

Purpose: To examine shoe-surface interactions on newer field designs and compare these with more traditional shoe-surface combinations. The peak torque and rotational stiffness (the rate at which torque is developed under rotation) were determined.

Mechanical characterization of collagen fibers and scaffolds for tissue engineering.

Engineered tissues must utilize scaffolding biomaterials that support desired cellular functions and possess or can develop appropriate mechanical characteristics. This study assessed properties of collagen as a scaffolding biomaterial for ligament replacements. Mechanical properties of extruded bovine achilles tendon collagen fibers were significantly affected by fiber diameter, with smaller fibers displaying higher tangent moduli and peak stresses.

Research report: learning styles of biomedical engineering students.

Examining students' learning styles can yield information useful to the design of learning activities, courses, and curricula. A variety of measures have been used to characterize learning styles, but the literature contains little information specific to biomedical engineering (BMEN) students. We, therefore, utilized Felder's Index of Learning Styles to investigate the learning style preferences of BMEN students at Tulane University.