Determining the areas of brain activity associated with cognitive processing has typically relied on the use of a subtraction paradigm, which is based on the premise that the neural processes underlying behavior are additive. If the additivity assumption is valid then brain regions associated with a semantic processing task should be the same regardless of how participants make a response. To i...

A major complaint of individuals with normal hearing and hearing impairments is a reduced ability to understand speech in a noisy environment. This paper describes the concept of adaptive noise cancelling for removing noise from corrupted speech signals. Application of adaptive digital signal processing has long been known and is described from a historical as well as technical perspective. The...

We have studied the chromosphere of active binary systems using the information provided by several optical spectroscopic features that could be used as chromospheric activity indicators. The simultaneous observations of diierent lines, that are formed at diierent heights in the chromosphere (from the region of temperature minimum to the higher chromosphere), are of special interest for stellar...

Time-dependent subtraction techniques have tremendously improved the visualization of iodinated vessels. These techniques suffer from motion artifacts, however, since the mask image is acquired several seconds prior to the contrast image. A K-edge subtraction technique for selectively imaging iodine using the characteristic x rays from a lanthanum secondary target is presented. The K alpha line...

It is often difficult for radiologists to identify small hepatocellular carcinomas (HCCs) due to insufficient contrast enhancement. Therefore, we have developed a new computer-aided temporal and dynamic subtraction technique to enhance small HCCs, after automatically selecting images set at the same anatomical position from the present (non-enhanced and arterial-phase CT images) and previous im...

BACKGROUND AND PURPOSE Many wide-necked aneurysms are difficult or impossible to treat with the Guglielmi detachable coil (GDC). The purpose of this study was to evaluate the use of a neck bridging device, the TriSpan coil, in combination with standard GDCs for the treatment of wide-necked aneurysms in an experimental canine aneurysm model. METHODS Of 24 experimental aneurysms in 12 animals, ...