This paper deals with pricing and modal split in a competitive mass transit/highway system with heterogeneous commuters. Two groups of commuters that di€er in their disutility from travel time, schedule delay and transit crowding, select the transit or auto mode for traveling from a residential area to a workplace. We compare three pricing schemes: the marginal cost-based transit fare with no-t...

A novel temporal correlation technique was used to map the first-pass transit of iodinated contrast agents through the brain. Transit profiles after bolus injections were measured with dynamic computed tomography (CT) scanning (1 image/s over 50 s). A rabbit model of focal cerebral ischemia (n = 6) was used, and dynamic CT scans were performed at 30, 60, 90, and 120 min postocclusion. Within th...

AIM Individuals with human immunodeficiency virus (HIV) infection were evaluated for evidence of abnormal polymorphonuclear leucocyte (PMN) rigidity, which can alter capillary blood flow. METHODS The transit time of individual PMN through 8 microm pores in a cell transit analyser was used as a measure of cell rigidity. PMN transit time was compared between HIV infected individuals (n=45) with...

Objective methods for examination of pouch function are warranted for a better understanding of the functional result and treatment of dysfunction. The objective of this study was to evaluate the results of scintigraphic intestinal transit time and defaecography compared to the results of pouch function, mucosal condition and a questionnaire on quality of life (QoL). This cross-sectional study ...

AIM: To determine the effect of oral erythromycin on gastric and small bowel transit time of capsule endoscopy. METHODS: Consecutive patients who underwent capsule endoscopy during the 16-mo study period were either given 250 mg oral erythromycin, 1 h prior to swallowing the capsule endoscope or nothing. The gastric and small bowel transit time, and the small bowel image quality were compared. ...

Introduction The blood transit time from arterial spin labeling plane to capillaries in the imaging slice (referred to as “tissue transit time”) decreased during neuronal activation in humans (1), while it appeared no changes during somatosensory stimulation in rats (2). Since a tissue transit time is shorter in rats compared to humans, shortening blood transit time may not be detectable with a...

Delayed effects for pharmacodynamic responses can be observed for many signal transduction processes. Three approaches are summarized in this report to describe such effects caused by cascading steps: stochastic process model, gamma distribution function, and transit compartment model. The gamma distribution function, a probability density function of the waiting time for the final step in a st...

Motivated by applications in road traffic control, we study flows in networks featuring special characteristics. Firstly, there are transit times on the arcs of the network which specify the amount of time it takes for flow to travel through an arc; in particular, flow values on arcs may change over time. Secondly, the transit time of an arc varies with the current amount of flow using this arc...

A magnetic resonance image (MRI)-based method to determine the colonic transit time is described. It is based on the oral ingestion of a single dose of 4 ml Gd-DOTA following an overnight fast and the subsequent acquisition of fast three-dimensional (3D) gradient-echo sequences under apnea conditions. The technique was successfully evaluated in three healthy volunteers. Transit of the contrast ...