Only about half of non-membrane-bound proteins encoded by either bacterial or archaeal genomes are soluble when expressed in Escherichia coli (Yee et al., Proc Natl Acad Sci USA 2002;99:1825-1830; Christendat et al., Prog Biophys Mol Biol 200;73:339-345). This property limits genome-scale functional and structural proteomics studies, which depend on having… (More)
Femtosecond electron bunches with ultra-relativistic energies were recently generated by laser wakefield accelerators. Here we predict that such accelerators can generate stable attosecond bunches, due to betatron phase mixing within a femtosecond electron bunch.
It is shown that an undesirable curvature of the wave front of a two-dimensional nonlinear wake wave, excited in uniform plasma by a relativistic charged bunch or laser pulse, may be compensated by radial change of the equilibrium plasma density.