Developing a model system to test the mechanobiology of tissues ex-vivo is a complex task, as controlling chemical and mechanical boundary layers in-vitro are difficult to replicate.
Sliding speeds on the order of 1000 m/s and contact pressures in excess of 100 MPa are common in these applications and difficult to replicate in a laboratory environment.
3 5 6 While laboratory tests are used to evaluate basic performance characteristics in most individual sports, field-based methods are better suited to the demands of complex intermittent sports like tennis, since the variability in energy system, muscle group and skill incorporated in their performance is difficult to replicate in the laboratory.
Yet it seems the finesse and specialized skill that elevate the best tennis players in the world are difficult to replicate in a game; facets of tennis like putting specific spin on shots and employing strategy in shot placement have never been completely translated into a tennis video game.
Articular cartilage is a highly organized tissue that is well adapted to the functional demands in joints but difficult to replicate via tissue engineering or regeneration.
There appears to be a general acceptance that the synthesis process, not unlike analysis in primary qualitative research, "cannot be reduced to mechanistic tasks" [ 4] and may, in practice, be difficult to replicate.
Although differences in brain anatomy in autism have been difficult to replicate using manual tracing methods, automated whole brain analyses have begun to find consistent differences in regions of the brain associated with the social cognitive processes that are often impaired in autism.
These tissues and organs contain multiple cell types and extracellular matrices arranged in specific patterns that are difficult to replicate in vitro.
Now, as the NFL said in the press release announcing the settlement, "the underlying theory of this lawsuit about what took place in the past would be difficult to replicate in the future.
