Calculations indicate that the introduction of hydrogen into the body–centred cubic and face-centred cubic allotropes of iron in both cases reduces the {100} surface energy. The reduction is rather small in magnitude so this mechanism cannot present the major cause of the well–known hydrogen embrittlement phenomenon. Consistent with the theory of grain boundary embrittlement in iron, carbon is ...

The knowledge of the fracture of bulk metallic materials developed in the last 50 years is mostly based on materials having grain sizes, d, in the range of some micrometres up to several hundred micrometres regarding the possibilities of classical metallurgical methods. Nowadays, novel techniques provide access to much smaller grain sizes, where severe plastic deformation (SPD) is one of the mo...

OBJECTIVE To estimate the utility (preference for health) associated with hip fracture and fear of falling among older women. DESIGN Quality of life survey with the time trade off technique. The technique derives an estimate of preference for health states by finding the point at which respondents show no preference between a longer but lower quality of life and a shorter time in full health....

A fully coupled hydrological–mechanical–chemical (HMC) model is developed and applied to explain enigmatic spontaneous changes in permeability that develop within a fracture in limestone under simulated in situ conditions (Water Resour Res 2004;40:W03502). The water flow-through test was concurrently monitored for water and dissolved mineral mass efflux and periodically imaged by X-ray CT to pr...

Specialized areas within broad, close, cell-substratum contacts seen with reflection interference contrast microscopy in cultures of Xenopus embryonic muscle cells were studied. These areas usually contained a distinct pattern of light and dark spots suggesting that the closeness of apposition between the membrane and the substratum was irregular. They coincided with areas containing acetylchol...

Specific labeling of a single row of cellulose-synthesizing complexes (terminal complexes, TC subunits, TCs, or TC arrays) in Acetobacter xylinum by antibodies raised against a 93-kDa protein (the cyclic dignanylic acid-binding protein) has been demonstrated by using the sodium dodecyl sulfate (SDS)-freeze-fracture labeling (FRL) technique. The antibodies to the 93-kDa protein specifically reco...

L'association fracture de la diaphyse fémorale et fracture de Hoffa de l'extrémité inférieure du même fémur est très rare, peu de cas sont décrit dans la littérature. Elles surviennent après un traumatisme à haute énergie surtout lors des accidents de la voie publique. Elles touchent par conséquent une population jeune. Notre patient est âgé de 27 ans, il a été victime d'un accident grave en co...

Posttraumatic hematoma of the face is common and usually self-limiting in nature. We report an unusual massive expanding hematoma of the chin within 9 h following a blunt trauma with no associated injuries or fracture.