JOEL ARNEODO*, SOLEDAD DE BREUIL*, SERGIO LENARDON**, LUIS CONCI**

BIOCELL, Vol.29, No.2, pp. 205-207, 2005, DOI:10.32604/biocell.2005.29.205

Abstract Plants of Viola cornuta displaying typical virus symptoms were observed during spring 2003 in a plant nursery in Córdoba, central Argentina. Electron microscopic examinations of symptomatic leaf samples revealed the presence of isometric virus-like particles about 30 nm in diameter. Subsequent serological analysis allowed the identification of the pathogen as a subgroup I strain of Cucumber mosaic virus (CMV). These results were confirmed by antigen capture - reverse transcription - polymerase chain reaction with specific CMV primers, and digestion with a restriction enzyme. This is the first report of CMV infecting V. cornuta in Argentina. More >

LUCIANA FIORETTI GRACIOLI-VITTI, FÁBIO CAMARGO ABDALLA, REGINA LÚCIA MORELLI SILVA DE MORAES

BIOCELL, Vol.29, No.1, pp. 1-5, 2005, DOI:10.32604/biocell.2005.29.001

Abstract The aim of the present study was analyze, by histological and morphometrical studies, mandibular glands of Melipona bicolor queens collected from monogynic and polygynic colonies and compare their level of development. The results showed that the glands of physogastric queens from monogynic colony present a higher level of activity in relation to the queens of polygynic colonies; this is explained by the fact that just a unique queen controls the monogynic colony. In the polygynic colonies, the queens may divide such control to each other. More >

C. Braccesi¹, F. Cianetti¹, G. Lori¹, D. Pioli¹

Structural Durability & Health Monitoring, Vol.1, No.4, pp. 277-290, 2005, DOI:10.3970/sdhm.2005.001.277

Abstract This paper describes an original frequency method for fatigue life estimation of mechanical components subjected to random inputs. Currently mechanical components life design under random loads is an important task of the research, due to the increasing importance of virtual simulation in opposition to the experimental tests. The frequency domain approach, in this context, seems to be able to supply reliable estimations with small computational effort. The proposed method belongs to the class of corrective coefficient to narrow-band formula methods and it has been thought for bimodal PSDs. The definition of the generalized bimodal processes and More >

A. Rama Ch,ra Murthy¹, G.S. Palani¹, Nagesh R. Iyer¹

Structural Durability & Health Monitoring, Vol.1, No.3, pp. 203-214, 2005, DOI:10.3970/sdhm.2005.001.203

Abstract This paper presents an improved Wheeler residual stress model for remaining life prediction of the cracked structural components under variable amplitude loading. The improvement to the Wheeler residual stress model is in two folds. One is expressions for the shaping exponent, which are generally obtained through experiments. Another is calculation of effective plastic zone size to incorporate the sequent effects under tensile-compressive overloading. The remaining life prediction has been carried out by employing the linear elastic fracture mechanics (LEFM) principles. Studies on remaining life prediction of cracked plate panels subjected to tensile-compressive overloading have been More >

D.Taylor¹

Structural Durability & Health Monitoring, Vol.1, No.2, pp. 145-154, 2005, DOI:10.3970/sdhm.2005.001.145

Abstract The Theory of Critical Distances (TCD) is a general term for any of those methods of analysis which use continuum mechanics in conjunction with a characteristic material length constant, L. This paper discusses the use of two simple versions of the TCD: a point-stress approach which we call the Point Method (PM) and a line-average approach: the Line Method (LM). It is shown that they are able to predict the onset of unstable, brittle fracture in specimens of metallic materials containing notches of varying root radii. The approach was successful whatever the micromechanism of crack… More >

P. Horst¹

Structural Durability & Health Monitoring, Vol.1, No.1, pp. 49-66, 2005, DOI:10.3970/sdhm.2005.001.049

Abstract The paper presents a Monte Carlo Simulation method for the assessment of Multiple Site Damage (MSD) and a subsequent attempt to find a way to interpret intermediate results of the Monte Carlo Simulation with respect to the criticality of scenarios. The basic deterministic part of the model is based on the compounding method, which is used in order to gain an acceptable computational effort. Some examples illustrate features of MSD scenarios and this allows to check an approach for feature detection via Wavelet transforms. This Wavelet transform approach shows some positive results in the interpretation More >

Dimitrije Stamenovic´ ¹

Molecular & Cellular Biomechanics, Vol.2, No.2, pp. 69-76, 2005, DOI:10.3970/mcb.2005.002.069

Abstract It is well established that adherent cells change their orientation in response to non-uniform substrate stretching. Most observations indicate that cells orient away from the direction of the maximal substrate strain, whereas in some cases cells also align with the direction of the maximal strain. Previous studies suggest that orientation and steering of the cell may be closely tied to cytoskeletal contractile stress but they could not explain the mechanisms that direct cell reorientation. This led us to develop a simple, mechanistic theoretical model that could predict a direction of cell orientation in response to More >

Quang Dang^1,1, Hans Gregersen^2,2, Birgitte Duch^2,2, Ghassan S. Kassab^1,1

Molecular & Cellular Biomechanics, Vol.2, No.2, pp. 53-62, 2005, DOI:10.3970/mcb.2005.002.053

Abstract Biliary duct obstruction is an important clinical condition that affects millions of people worldwide. We have previously shown that the common bile duct (CBD) undergoes significant growth and remodelling post obstruction. The mechanical stress-strain relation is expected to change due to growth and remodeling in response to obstruction and hence pressure-overload. The objective of the present study was to characterize the material properties of the CBD of the sham group and at 3 hours, 12 hours, 2 days, 8 days and 32 days (n=5 in each group) after obstruction. The Fung's exponential strain energy function… More >

Wei Zhang^1,2, Carly Herrera¹, Satya N. Atluri¹, Ghassan S. Kassab^2,3

Molecular & Cellular Biomechanics, Vol.2, No.1, pp. 41-52, 2005, DOI:10.3970/mcb.2005.002.041

Abstract It is well known that blood vessels shorten axially when excised. This is due to the perivascular tethering constraint by side branches and the existence of pre-stretch of blood vessels at the \textit {in situ} state. Furthermore, vessels are radially constrained to various extents by the surrounding tissues at physiological loading. Our hypothesis is that the axial pre-stretch and radial constraint by the surrounding tissue homogenizes the stress and strain distributions in the vessel wall. A finite element analysis of porcine coronary artery and rabbit thoracic aorta based on measured material properties, geometry, residual strain More >

S.C. Forth¹, A. Staroselsky²

CMES-Computer Modeling in Engineering & Sciences, Vol.9, No.3, pp. 287-298, 2005, DOI:10.3970/cmes.2005.009.287

Abstract A new hybrid surface-integral-finite-element numerical scheme has been developed to model a three-dimensional crack propagating through a thin, multi-layered coating. The finite element method was used to model the physical state of the coating, and the surface integral method was used to model the fatigue crack growth. The two formulations are coupled through the need to satisfy boundary conditions on the crack and external surface. The coupling is sufficiently weak that the surface integral mesh of the crack surface and the finite element mesh of the uncracked volume can be set up independently. Thus, when More >