Abstract: Systems and methods that integrate a directional coupling function with directivity that does not have output loss are disclosed. For example, a power amplifier circuit arrangement includes an input terminal to receive an input signal; amplifier circuitry including a first amplifier stage, a second amplifier stage, and a virtual ground node, where an input of the first amplifier stage is coupled to the input terminal, an output of the first amplifier stage is coupled to an input of the second amplifier stage via the virtual ground node, and an output of the second amplifier stage is coupled to the input of the first amplifier stage via feedback circuitry; an output terminal coupled to the output of the second amplifier stage, the output terminal to output an amplified signal; and a directional coupler terminal coupled to the virtual ground node.

Abstract: The present disclosure relates to the use of ligands of complement receptor 3, including ligands of the I domain of the alpha subunit of this receptor, in methods, compositions and articles/devices for inhibiting the interaction of pathogens to a complement receptor 3-expressing cell and for treating or inhibiting the development of infections caused by such pathogens.