During discontinuous gas exchange cycles in insects, spiracular opening follows a typical prolonged period of spiracle closure. Gas exchange with the environment occurs mostly during the period of full spiracular opening. In this study we tested the hypothesis that recently reported ventilatory movements during the spiracle closure period serve to mix the tracheal system gaseous contents, and s...

The feasibility of shutter-speed model dynamic-contrast-enhanced MRI pharmacokinetic analyses for prostate cancer detection was investigated in a prebiopsy patient cohort. Differences of results from the fast-exchange-regime-allowed (FXR-a) shutter-speed model version and the fast-exchange-limit-constrained (FXL-c) standard model are demonstrated. Although the spatial information is more limite...

Peptide mixtures, arising from such diverse sources as tissue extracts, urine or proteolysis, are usually fractionated and characterized by a combination of ion-exchange chromatography, gel-exclusion chromatography and/or electrophoresis. Appropriate combinations of these methods will normally yield a homogeneous product, but their costs, detection limits, analyses times and yields vary. The re...

Introduction Infrared imaging permits to map the surface thermal distribution of the human body. A large number of studies has been so far established to assess the contribution that such information may provide to the clinicians. Cutaneous temperature distribution depends on complex relationships defining the heat exchange processes between cutaneous tissue, inner tissue, local vasculature, an...

Introduction Contrast agents (CA) are commonly used in MRI to generate a detectable contrast between areas of interest and the surrounding tissue. However, the CA may accumulate in a specific area. In this situation it is possible that the exchange of water molecules between the area with CA and the surrounding tissue is not fast enough to preserve the conditions of the fast exchange limit and ...