Techniques for Studying Arterial Elastic Properties To the Editor: I applaud the effort of Rietzchel and colleagues1 to compare two techniques in wide use for studying arterial elastic properties. This is a study long in need of performance because of the controversial claims in the literature relating to the theory of systolic and diastolic waveform analysis. As we had anticipated and predicte...

Chromatin is a complex of DNA and specific proteins forming an intermediary level of organization of eukaryotic genomes, between double-stranded DNA and chromosome. Within a generic modeling of the chromatin assembly, we investigate the interplay between the mechanical properties of the chromatin fiber and its biological functions. A quantitative step is to relate the mechanics at the DNA level...

In multidisciplinary studies carried out in the Budare Oil Field of the Great Oficina Oil Field, there was difficulty matching well log synthetic seismograms with 2D and 3D seismic data. In addition, the seismically determined depths of reservoir horizons are greater than the well sonic log depths. To examine this discrepancy we conducted an experimental study of dynamic elastic parameters of t...

1Student of Masters in Orthodontics, Department of Odontopediatrics and Orthodontics, Dental School, Federal University of Rio de Janeiro (FO-UFRJ), Rio de Janeiro, RJ, Brazil. 2Master in Orthodontics, Department of Orthodontics, Dental School, Federal University of Rio de Janeiro (FO-UFRJ), Rio de Janeiro, RJ, Brazil. 3Master in Orthodontics, Department of Orthodontics, Dental School, Federal ...

This chapter examines the effects of femoral neck geometry and topological structure on elastic properties. A finite element code is used to calculate the full elastic tensor for thirteen human proximal femur specimens. We show that the micro-structure within the human femoral neck and head gives rise to approximate orthotropic elastic symmetry at the whole bone scale. The finite element code c...

the changes in viscoelastic properties of potatoes (tubuls agria) stored at 4 ˚c for 4 months were modeled and evaluated by using the creep-recovery test. cylindrical specimens with 15 mm in diameter and 35 mm long were used. the samples were allowed to deform gradually under the constant stress (110 kpa) for about 30 min. after removing the load, the sample recovery was registered. deformation...

in this research, static stresses analysis of boron nitride nano - tube reinforced composite (bnntrc) cylinder made of poly - vinylidene fluoride (pvdf) subjected to non - axisymmetric thermo - mechanical loads and applied voltage is developed. the surrounded elastic medium is modelled by pasternak foundation. composite structure is modeled based on piezoelectric fiber reinforced composite (pfr...

to evaluate the earth seismic response due to earthquake effects, ground response analyses are used to predict ground surface motions for development of design response spectra, to compute dynamic stresses and strains for evaluation of liquefaction hazards, and to determine the earthquake induced forces that can lead to instability of earth and earth-retaining structures. most of the analytical...

This paper presents the results of the elastic and geometrical properties of four types of nanostructured hierarchical and self-similar honeycombs. It is shown that at the nanometer scale, the elastic properties are size-dependent; the thinner the first order cell walls, the stiffer the hierarchical honeycombs. As an initial strain can be applied and controlled to the first order cell walls by ...

The effect of differentiation on the transverse mechanical properties of mammalian myocytes was determined by using atomic force microscopy. The apparent elastic modulus increased from 11.5 +/- 1.3 kPa for undifferentiated myoblasts to 45.3 +/- 4.0 kPa after 8 days of differentiation (P < 0.05). The relative contribution of viscosity, as determined from the normalized hysteresis area, ranged fr...