Motile organisms can expand into new territories and increase their fitness, while nonmotile viruses usually depend on host migration to spread across long distances. In general, faster host motility facilitates virus transmission. However, recent ecological studies have also shown that animal host migration can reduce viral prevalence by removing infected individuals from the migratory group.
View Article and Find Full Text PDFHigh-order harmonics generated from atoms driven by counter-rotating two-color circularly (CRTC) polarized laser fields are studied in the frame of a quantum-field scattering theory. We use a pair of generalized phased Bessel (GPB) functions to describe the harmonic generation amplitude. The use of GPB functions allows us to define the phase of a harmonic channel accurately, by which we obtain the spin angular momentum conservation relation in a straightforward way.
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