Little is known about the mechanical properties of the growing femoral head as it develops deformity following ischemic injury. The purpose of this study was to determine the indentation stiffness of growing femoral head following ischemic injury and to correlate the changes in stiffness with radiographic and histopathologic changes in the femoral head as it develops deformity. Following the in...

We consider the point indentation of a pressurized, spherical elastic shell. Previously it was shown that such shells wrinkle once the indentation reaches a threshold value. Here, we study the behaviour of this system beyond the onset of instability. We show that rather than simply approaching the classical “mirror-buckled” shape, the wrinkled shell approaches a new, universal shape that reflec...

A methodology for interpreting instrumented sharp indentation with dual sharp indenters with different tip apex angles is presented by recourse to computational modeling within the context of finite element analysis. The forward problem predicts an indentation response from a given set of elasto-plastic properties, whereas the reverse analysis seeks to extract elasto-plastic properties from dep...

Abstract Background Gastrointestinal tract can be compressed by many vascular structures in the abdomen; such compressions may incidentally found or result compression symptoms like abdominal pain and vomiting. Case presentation We illustrate an uncommon cause of extrinsic third part duodenum jejunal branches superior mesenteric artery 18-year-old female, presented with dull-aching epigastric C...

The molecular dynamic technique was used to simulate the nano-indentation test on the thin films of silver, titanium, aluminum and copper which were coated on the silicone substrate. The mechanical properties of the selected thin films were studied in terms of the temperature. The temperature was changed from 193 K to 793 K with an increment of 100 K. To investigate the effect of temperature on...

Nanoindentation became a versatile tool for testing local mechanical properties beyond hardness and modulus. By adapting standard nanoindentation test methods, simple protocols capable of probing thermally activated deformation processes can be accomplished. Abrupt strain-rate changes within one indentation allow determining the strain-rate dependency of hardness at various indentation depths. ...

The biphasic poroviscoelastic (BPVE) model was curve fit to the simultaneous relaxation of reaction force and lateral displacement exhibited by articular cartilage in unconfined compression (n=18). Model predictions were also made for the relaxation observed in reaction force during indentation with a porous plane-ended metal indenter (n=4), indentation with a nonporous plane ended metal indent...

Deformity of the forearm due to growth disturbance of the ulna occurs in a number of conditions such as ulnar deficiency, multiple exostoses, and neurofibromatosis. We report a previously unrecognised form, caused by focal cortical indentation. We have treated five children with this condition, three girls and two boys; the mean age at presentation was 5 years (2 to 8). The deformity was first ...

A new physical model based on mesoscale self-assembly is developed to simulate indentation fracture in crystalline materials. Millimeter-scale hexagonal objects exhibiting atom-like potential functions were designed and allowed to self-assemble into two-dimensional (2D) aggregates at the interface between water and perfluorodecalin. Indentation experiments were performed on these aggregates, an...