This type of pairwise comparison is appropriate for much of the methylation data currently available, but existing methods are challenging to generalize to analysis of more densely sampled sets of dependent cell types.
While new technologies such as optical resonators and nanowire sensors provide the advantage of direct ligand target affinity measurements, these methods are challenging to implement in complex media, at physiological salt, and in a high-throughput fashion.
Due to the variety of existing methods, it is challenging to define an appropriate method for each decision problem.
These recovery methods are extremely challenging to simulate because of the very strong nonlinearities in the governing equations.
However, these numerical methods are still challenging to apply due to complicated gridding issues, an expensive computational cost, and complexities in development of computational codes.
In most free surface based methods, it is challenging to create a reproducible molecular extension, as the surface bound molecule can be overstretched and is free to deviate from a completely straight trajectory.
However, matching gels to their respective Western blots from typical 2DGE methods is extremely challenging to computational geometric algorithms (11).
With current methods, it's often challenging to image ovarian tumors smaller than one centimeter in diameter without surgery.
The Socratic Method challenges one to produce reasons for one's view.
However, this method is challenging due to the high cost of the equipment required and the need for trained personnel.
However, repair of articular cartilage by traditional methods is challenging, due to its avascular nature and lack of a significant population of progenitor cells.
