Abstract: A glass fiber mat includes glass fibers saturated with a binder and then cured. A predetermined pattern of relatively high and low concentrations of binder is formed throughout the length of the glass fiber mat. The pattern produces at least one portion of the mat having a relatively high concentration of binder adjoining a portion of the mat having a relatively low concentration of binder. The pattern of high and low binder concentration is produced during a wet process. Liquid binder is either selectively applied to the glass fibers via an applicator or selectively removed from the glass fibers via a vacuum. Cover panels having predetermined slot configurations are used with vacuum boxes to create the desired pattern. Such glass fiber mats can be cut along an area of high binder concentration to produce cut edges which resist breaking and tearing. Shingles formed from such glass fiber mats have improved tear resistance and pliability.

Abstract: The present invention involves an apparatus and method for detecting and treating fibrillation in the heart. Electrodes sense electrical activity in two distinct locations of the heart. The electrocardiac activations are monitored and the interval between activations at the two locations is measured and checked for variation. Upon detection of significant variation in the length of the intervals, the fibrillation condition is determined and a defibrillator is activated, so that a defibrillating shock may be delivered to the heart. For atrial fibrillation, the first defibrillating shock is relatively low and is increased until the fibrillation is no longer detected.