1. The effect of head-up tilt upon subcutaneous blood flow in the distal arm and leg was studied in 12 patients with complete traumatic spinal cord transection at the cervical level. 2. Blood flow was measured by the local 133Xe washout technique. 3. Leg lowering induced a 47% decrease in blood flow in the distal leg. During head-up tilt (45 degrees) blood flow in the leg decreased by 48%. In t...

Head-up tilt test was performed in 99 patients with syncope of unknown origin and intraventricular conduction defect. Twenty-five per cent had a positive response to tilt with reproduction of spontaneous clinical symptoms. Holter recording revealed paroxysmal atrioventricular (AV) block in three patients. Carotid sinus massage was positive in four patients. An electrophysiological study was per...

BACKGROUND Most subjects with blood/injury phobia experience syncope or presyncope as part of the phobic response. We tested the hypothesis that these subjects have a constitutional autonomic dysregulation that predisposes them to vasovagal syncope during head-up tilt. METHODS AND RESULTS We studied 11 subjects (9 females, 2 males) who had a history of syncope or presyncope only in response t...

This paper explores the tilt illusion effect in the Café Wall pattern using a classical Gaussian Receptive Field model. In this illusion, the mortar lines are misperceived as diverging or converging rather than horizontal. We examine the capability of a simple bioplausible filtering model to recognize different degrees of tilt effect in the Café Wall illusion based on different characteristics ...

IN 1895 Leonard Hill' concluded from his experimental work on the blood pressure and heart rate of animals that the effect of changing the position afforded a most delicate test of the vasomotor mechanism. The development of accurate methods of continuous recording made it possible to confirm these conclusions in man. Previous studies2 3 of normal subjects established a definite pattern of bloo...

Tilt-shift camera lenses are a powerful artistic tool to achieve effects like selective focus with very shallow depth of field. Typically they are used by professional photographers only, which is due to the high cost and weight, and the intricate, non-intuitive handling. We introduce the auto-tilt mechanism which is as easy to use as the standard autofocus. It allows automatic sharp focus of o...

BACKGROUND In patients with vasovagal syndrome, head-up tilt testing may reproduce symptoms generally associated with vasodepression. Recent research suggests ATP testing identifies patients with abnormal vagal cardiac inhibition. This preliminary study examined the joint contribution of both tests in identifying underlying mechanisms in the general population with vasovagal syndrome. METHODS...

The first theoretical description of the experimentally often-observed isotropic-polar smectic phase transitions of symmetric and asymmetric bent-shape molecules is presented. The isotropic-tilted polar smectic phase transition requires a coupling among three types of ordering processes: polar packing, director tilt, and layer ordering. For explaining the unusual triclinic-monoclinic phase tran...

It has recently been shown that a Hagedorn phase of string gas cosmology can provide a causal mechanism for generating a nearly scale-invariant spectrum of scalar metric fluctuations, without the need for an intervening period of de Sitter expansion. In this Letter, we compute the spectrum of tensor metric fluctuations (gravitational waves) in this scenario and show that it is also nearly scale...