We have observed that hydrogen peroxide (H2O2), the dismutated product of superoxide, is a coronary metabolic dilator and couples myocardial oxygen consumption to coronary blood flow. Because the chemical activity of H2O2 favors its role as an oxidant, and thiol groups are susceptible to oxidation, we hypothesized that coronary metabolic dilation occurs via a redox mechanism involving thiol oxi...

Perceived duration of a sensory event often exceeds its actual duration. This phenomenon is called time dilation. The distortion may occur because sensory systems are optimized for perception within their respective modalities and not for perception of time. We investigated how the dilation of visual events depends on the duration and content of events. Observers compared the durations of two s...

To determine the skeletal muscle stimulation parameters that are most important in establishing vasodilation in the microvasculature, I tested whether arteriolar diameter during 2 min of repetitive, short-duration, tetanic skeletal muscle contractions increased with changes in stimulus frequency, stimulation train duration, and contraction frequency. To test this, the diameter of transverse art...

OBJECTIVE To assess the clinical significance of transient ischemic dilation of the left ventricle during myocardial perfusion scintigraphy with stress/rest sestamibi. METHODS The study retrospectively analyzed 378 patients who underwent myocardial perfusion scintigraphy with stress/rest sestamibi, 340 of whom had a low probability of having ischemia and 38 had significant transient defects. ...

FIGURE 8-12 International system of radiographic grading of vesicoureteral reflux (VUR). The severity of VUR is most frequently classified according to the International Grading System of Vesicoureteral Reflux, using a standardized technique for performance of voiding cystourethrography. The definitions of this system are illustrated in Figure 8-4 and are as follows. In grade I, reflux only int...

Glossary Dilation matrix A 2× 2 matrix M is called a dilation matrix if all the entries of M are integers and all the eigenvalues of M are greater than one in modulus. Isotropic dilation matrix A dilation matrix M is said to be isotropic if M is similar to a diagonal matrix and all its eigenvalues have the same modulus. Wavelet system A wavelet system is a collection of square integrable functi...

Given a planar graph G, the graph theoretic dilation of G is defined as the maximum ratio of the shortestpath distance and the Euclidean distance between any two vertices of G. Given a planar point set S, a triangulation of S that achieves minimum graph theoretic dilation is called a minimum dilation triangulation of S. In this paper, we show that a simple exclusion region for an edge e of the ...

In this paper, it is shown how differential-dilation equations can be constructed using iterations, similar to the iterations with which wavelets and dilation equations are constructed. A continuous-time wavelet is constructed starting from a differential-dilation equation. It has compact support and excellent time domain and frequency domain localization properties. The wavelet is infinitely d...

The pharmaceutical industry requires the use of lubricants to prevent static electric buildup in the cohesive powders that are processed in manufacturing plants. In this report we examine the effects of common lubricant magnesium stearate on two flow properties, flow index and dynamic dilation, of lactose. We conducted two experiments using a gravitational displacement rheometer and a dynamic d...

Multiple-unit recordings were obtained from the interstitial nucleus of Cajal, nucleus of Darkschewitsch and the superior colliculus of the cat during acquisition of classically conditioned pupillary dilation. Multiple-unit responses in all regions were enhanced by conditioning procedures. However, only the acquisition functions for the accessory oculomotor nuclei, i.e., interstitial nucleus of...