The bulk synthesis of highly crystalline noncatalytic low melting metals such as \u03b2-gallium oxide tubes, nanowires, and nanopaintbrushes is accomplished using molten gallium and microwave plasma containing a mixture of monoatomic oxygen and hydrogen. The process may be configured to construct a semiconductor structure having an etch-stop layer above a photodiode region and a first dielectric layer above the etch-stop layer. Chimeric human-bovine RSV of the invention include a partial or complete \u201cbackground\u201d RSV genome or antigenome derived from or patterned after a human or bovine RSV strain or subgroup virus combined with one or more heterologous gene or genome segment of a different RSV strain or subgroup virus to form the human-bovine chimeric RSV genome or antigenome. Alternatively, the stirrer may be installed in an inclined angle and can change the cavity shape of the cooking chamber when rotating.