The monomolecular organization of the main tetraether phospholipid from the archaeon Thermoplasma acidophilum was studied by means of a Langmuir film balance integrated into a fluorescence microscope. After transfer to solid surfaces at different pressures the films were further investigated by ellipsometry, small angle X-ray scattering and atomic force microscopy. In order to complete former r...

Background: Tuberculosis is the second most common fatal infectious disease after Acquired Immunodeficiency Syndrome (AIDS) in the world. The spine is involved in 50% of osteoarticular tuberculosis cases. Tuberculous Spondylitis (TS) is the most dangerous form of osteoarticular tuberculosis, because of its ability to destroy the vertebral body with subsequent permanent kyphosis and neurological...

Typical quasistatic compression algorithms for generating jammed packings of purely repulsive, frictionless particles begin with dilute configurations and then apply successive compressions with the relaxation of the elastic energy allowed between each compression step. It is well known that during isotropic compression these systems undergo a first-order-like jamming transition at packing frac...

Cells from lung and other tissues are subjected to forces of opposing directions that are largely transmitted through integrin-mediated adhesions. How cells respond to force bidirectionality remains ill defined. To address this question, we nanofabricated flat-ended cylindrical Atomic Force Microscopy (AFM) tips with ~1 µm(2) cross-section area. Tips were uncoated or coated with either integrin...

An established aspect of force transmission in quasistatic deformation of granular media is the existence of a dual network of strongly versus weakly loaded particles. Despite significant interest, the regulation of strong and weak forces through the contact network remains poorly understood. We examine this aspect of force transmission using data on microstructural fabric from: (I) three-dimen...

Detailed investigation on biomechanics of a complex structure such as the human lumbar spine requires the use of advanced computer-based technique for both the geometrical reconstruction and the stress analysis. In the present study, the computer-assisted tomography (CAT) and finite element method (FEM) are merged to perform detailed three dimensional nonlinear analysis of the human ligamentous...

Using the results of psychophysical and biomechanical experiments, NIOSH (National Institute for Occupational Safety and Health) Recommended Weight Limit (RWL), the Lifting Index (LI), the form of the asymmetry multiplier, and the criterion for compression force were investigated. Analysis of the results indicated a significant difference between the NIOSH RWL and the reported Maximum Acceptabl...

STUDY DESIGN An in vivo rat model of transient cervical nerve root compression. OBJECTIVES To investigate the potential for cervical nerve root compression to produce behavioral hypersensitivity and examine its dependence on compression. SUMMARY OF BACKGROUND DATA Clinically, nerve root injury has been hypothesized as a potential source of neck pain, particularly because cervical nerve root...

BACKGROUND The knee joint performs mechanical functions with various loading and unloading processes. Past studies have focused on the kinematics and elastic response of the joint with less understanding of the rate-dependent load response associated with viscoelastic and poromechanical behaviors. METHODS Forty-five fresh porcine knee joints were used in the present study to determine the loa...