In one aspect, the invention is directed to a solar energy water heating system for heating water in a water storage tank. The search is implemented based on a query formulated from a natural language query. Furthermore, a method for determining an angular offset between a signal encoder of a rotor position encoder and a rotor position of an electronically commutated electric machine is provided. The invention further relates to kits and methods for producing the compositions and to the preproducts thereof. The present invention also includes methods to produce and use such nucleic acids, proteins, antibodies and therapeutic compositions capable of protecting animals from parasitic helminth infection and, particularly, from heartworm, infection.