Abstract: The invention puts forward a bidirectional DC-DC converter for high voltages that is as simple as possible and that entails as few losses as possible. The bidirectional DC-DC converter (1) converter comprises an input stage (2) to convert a DC input voltage into first AC voltage, a transformer (3) to transform the first AC voltage into a second AC voltage, and an output stage (4) to convert the second AC voltage into a DC output voltage, whereby, in order to provide the first and/or second AC voltage, at least one of the input stages (2) and/or output stages (4) comprises a branch of a multi-level converter (5) with a first number of active first semiconductor switches (61).

Abstract: The invention puts forward a bidirectional DC-DC converter for high voltages that is as simple as possible and that entails as few losses as possible. The bidirectional DC-DC converter (1) converter comprises an input stage (2) to convert a DC input voltage into first AC voltage, a transformer (3) to transform the first AC voltage into a second AC voltage, and an output stage (4) to convert the second AC voltage into a DC output voltage, whereby, in order to provide the first and/or second AC voltage, at least one of the input stages (2) and/or output stages (4) comprises a branch of a multi-level converter (5) with a first number of active first semiconductor switches (61).

Abstract: A reduced-toxicity formulation of carotenoids is disclosed which is stable in an aqueous environment. The formulation includes a carotenoid, lipid arrier particles (such as liposomes), and an intercalation promoter agent (such as a triglyceride), which causes the carotenoid to be substantially uniformly distributed with the lipid in the lipid carrier particles. The molar ratio of carotenoid to lipid is greater than about 1:10. Also disclosed is a method of inhibiting the growth of cancer cells, which comprises administering to a living subject a therapeutically effective amount of a composition as described above.