Methods and systems for controlling exposure for medical imaging devices is provided. The bracket unit is coupled pivotally to the base unit. An embodiment of the invention utilizes a general-purpose operating system to execute non-performance critical aspects of a domain, and uses a privileged VT-root mode to execute performance critical aspects of the domain. The plurality of analytes are simultaneously analyzed by collecting and recording images of the optical signals generated by all the microparticles in the planar array. In one embodiment, the beverage container is a multi-chambered container that includes a rotatable hollow member for storing the powdered substance, and a housing for securing the hollow member to the body such that a curved wall of the hollow member separates the powdered substance from the cooled liquid stored in the body. The shielding electrode is disposed over the bottom conductive wire.