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The effects of spinal cord injuries are likely to be ameliorated with the help of functional electrical stimulation of the spinal cord, a technique that may benefit from a new style of electrode: the cylindrical multielectrode. This paper describes the specifications for, fabrication techniques for, and in vitro evaluation of cylindrical multielectrodes. Four tip shapes were tested to determine which shape required the lowest peak force and would, therefore, be expected to minimize dimpling during implantation. The impedance of the electrode interface was monitored for changes due to insertion as well as repetitive delivery of current pulses. The charge delivery capacity was determined by testing with safe ([less than or equal to] 0.6 mC/[cm.sup.2]) and damaging levels ([greater than or equal to] 0.8 mC/[cm.sup.2]) of charge density. The results of these tests suggest that this electrode design could be used to stimulate neurons in the ventral horn of the spinal cord. Index Terms--Depth electrodes, impedance testing, microelectromechanical systems (MEMS), microstimulation, neural prosthesis.

The effects of spinal cord injuries are likely to be ameliorated with the help of functional electrical stimulation of the spinal cord, a technique that may benefit from a new style of electrode: the cylindrical multielectrode. This paper describes the specifications for, fabrication techniques for, and in vitro evaluation of cylindrical multielectrodes. Four tip shapes were tested to determine which shape required the lowest peak force and would, therefore, be expected to minimize dimpling during implantation. The impedance of the electrode interface was monitored for changes due to insertion as well as repetitive delivery of current pulses. The charge delivery capacity was determined by testing with safe (≤ 0.6 mC/cm²) and damaging levels (≥ 0.8 mC/cm²) of charge density. The results of these tests suggest that this electrode design could be used to stimulate neurons in the ventral horn of the spinal cord. [ABSTRACT FROM AUTHOR]

Databases may be compromised by asking a set of queries which return only statistical information and making inferences about a specific entry from the results of the set of queries. We present methods of constructing the set of queries to compromise a database where all the queries in the set return the maximum of a set of k elements, or all queries return the mean of a set of k elements. In the case of the mean query, all elements involved will be compromised. We also consider bounds on the number of queries required to compromise the database. [ABSTRACT FROM AUTHOR]

Presents a pathologic case study of juvenile ossifying fibroma seen in a patient with swelling of the maxilla. Clinical history of the patient; Results of physical and laboratory examinations performed on the patient; Information on the illness.