The present disclosure provides methods and systems comprising use of a device. A device may comprise a plurality of locations configured to contain one or more samples, a plurality of thermal elements corresponding and disposed adjacent to the plurality of locations, wherein the plurality of elements are configured to affect a thermal condition within individual locations of the plurality of locations, at least one additional thermal element operably coupled and common to at least a subset of the plurality of elements, wherein the additional thermal element is configured to affect at least one operating condition of the plurality of thermal elements at least partially in response to the thermal condition within the individual locations of the plurality of locations, and at least one optical system configured to detect a signal or change thereof from the individual locations of the plurality of locations, wherein the signal or change thereof is generated at least partially by a change of the thermal condition and is indicative of a property associated with the one or more samples.