The hydraulic performance of structured packed columns is characterised by parameters such as loading point, flooding point, dry and wet pressure-drop. These parameters can be positively influenced by optimising the transition areas between two adjacent packing layers. Tests have been done in a two-phase test rig with a rectangular column made of perspex. The test medium is a liquid hydrocarbon...

With the use of a restraint stress paradigm, both normotensive Wistar-Kyoto (WKY ) rats and spontaneously hypertensive rats (SHR) underwent acute (1-hour restraint in a Perspex tube), chronic (1-hour restraint for 10 consecutive days), or no-restraint (control) stress. Rats experiencing chronic restraint were previously implanted with telemetric probes to measure heart rate and blood pressure. ...

This paper details a practical method for deriving the reference air kerma rate calibration coefficient for Farmer NE2571 chambers using the U.K. Institute of Physics and Engineering in Medicine (IPEM) code of practice for the determination of the reference air kerma rate for HDR (192)Ir brachytherapy sources based on the National Physical Laboratory (NPL) air kerma standard. The reference air ...

Previous studies have shown that, during search flight in bats, wingbeat, respiration and echolocation are synchronised in a 1:1 relationship. An efficiently integrated locomotor-respiratory system enables bats to produce intense echolocation signals at little or no cost above that required for flight. In this study, we investigated the coupling of wingbeat with echolocation in the laboratory d...

In the present study, finite element calculations are performed of blood flow in the carotid artery bifurcation under physiological flow conditions. The numerical results are compared in detail with laser-Doppler velocity measurements carried out in a perspex model. It may be concluded that the numerical model as presented here is well capable in predicting axial and secondary flow of incompres...

BACKGROUND Many fundamental questions regarding the blood supply to the integument of the rat remain to be clarified, namely the degree of homology between rat and humans. The aim of this work was to characterize in detail the macro and microvascular blood supply to the integument covering the ventrolateral aspect of the abdominal wall of the rat. METHODS Two hundred five Wistar male rats wei...

With the use of a restraint stress paradigm, both normotensive Wistar-Kyoto (WKY ) rats and spontaneously hypertensive rats (SHR) underwent acute (1-hour restraint in a Perspex tube), chronic (1-hour restraint for 10 consecutive days), or no-restraint (control) stress. Rats experiencing chronic restraint were previously implanted with telemetric probes to measure heart rate and blood pressure. ...

Octopuses have large brains and exhibit complex behaviors, but relatively little is known about their cognitive abilities. Here we present data from a five-level learning and problem-solving experiment. Seven octopuses (Octopus vulgaris) were first trained to open an L shaped container to retrieve food (level 0). After learning the initial task all animals followed the same experimental protoco...

Crystals of Tipula iridescent virus (TIV)3 diffract light just as ordinary crystals diffract X-rays, so that a crystallographic study is possible using visible light. The conditions of growth of TIV crystals have been investigated and a method developed for preparing large crystals from the microcrystalline centrifuged virus pellets. Optical obsei vations using monochromatic light have been mad...

When performing foraging trips desert ants of the genus Cataglyphis continuously process and update a ;home vector' that enables them to return to their nest on the shortest route. This capacity of path integration requires two types of information: (i) information about the travelling directions, and (ii) odometric information about the distances travelled in a particular direction. We have in...