Abstract: An optical biological detector is able to bind specific targeted bacterial cells by stamping an antibody grating pattern onto a silicon surface. The antibody grating alone produces insignificant optical diffraction, but upon immunocapture of the targeted cells, the optical phase change produces a diffraction pattern. Micro-contact printing provides a method for placing the antibody grating pattern directly onto a substrate surface with no additional processes or binding chemicals. Antibodies or other biologically active material may be stamped directly onto clean native oxide silicon substrates with no other chemical surface treatments. Direct binding of the antibodies to the silicon occurs in a way that still allows them to function and selectively bind antigen. The performance of the sensor was evaluated by capturing Escherichia coli O157:H7 cells on the antibody-stamped lines and measuring the intensity of the first order diffraction beam resulting from the attachment of cells.

Abstract: A method and apparatus are described for selectively activating a secondary power source, such as a backup battery, for an electronic device, such as dynamic RAM. A connector is described in conjunction with a circuit board including a first contact coupled to the backup battery, and a second contact coupled to the corresponding input for backup power associated with an electronic device. In this state, an open circuit is presented such that the battery is isolated from the electronic device. A socket is described for cooperating with the connector, which includes mating contacts corresponding to the first and second contacts previously described, and a shunt for establishing electrical continuity between these mating contacts. In this manner, a completed circuit is established between the battery and the electronic device when the socket is attached.