This invention describes novel trunk piston engine lubricating oil compositions for use in trunk piston engines operating on low sulfur marine residual fuels, as well as methods for lubricating trunk piston engines, methods of using the trunk piston lubricating oil compositions, and methods of making thereof. In one embodiment, a microelectronic imager device includes an imager die having a substrate, a curved microelectronic image sensor having a face with a convex andor concave portion at one side of the substrate, and integrated circuitry in the substrate operatively coupled to the image sensor. Patient responses to the questions lead to more questions and ultimately to a diagnosis. The autotransformer serves to regulate the AC voltage output from generator via multiple output taps thereon for supplying various AC voltages to different external loads. The method is characterized by the high reaction rates and selectivities.