These data suggest the principles of biofilm-based wound care, along with the use of serial debridement to continually remove mature biofilm, followed by biofilm wound management strategies, including topical antibiotics while the bioburden is still immature and more susceptible, are valid.

Rheological effects may complicate the dispensing of complex fluids, when compared to their Newtonian counterparts. In this work, fluids with tailored rheological properties have been studied using high‐speed video‐microscopy. The level of viscosity, the degree of shear thinning, and the elasticity have been varied independently. At low‐flow rates, droplets are formed that pinch off. The drop volumes, breakup mechanisms, and times have been identified. At higher‐flow rates, a continuous jet is observed, with the transition depending on the rheology of the dispensed fluid. The relevant nondimensional groups are the Ohnesorge, Deborah, and elasto‐capillary number, for when viscosity, inertia, or elastic forces dominate flow. In each of these cases, the transition between dripping and jetting dispensing occurs, controlled by a critical Weber, capillary, and Weissenberg number, respectively. This set of six nondimensional groups can be used to construct an operating space and map out areas of potential problems. © 2011 American Institute of Chemical Engineers AIChE J, 58: 3242–3255, 2012

We present new observations of the gravitational lens system CLASS B0128+437. HST observations detect a very faint, extended object in I-band with no emission from the lensed images visible; no detection at all is made in V-band. The lens system is detected with much higher signal to noise with UKIRT in K-band, but the resolution is not sufficient to allow the lensed images and the lens galaxy to be separated. A careful astrometric calibration, however, suggests that the peak of the infrared emission corresponds to the two merging images A and B and therefore that the lensed images dominate at infrared wavelengths. The new radio data consist of VLBI radio images at three frequencies, 2.3, 5 and 8.4GHz, made with the VLBA and the 100-m Effelsberg telescope. The lensed source consists of three well-defined sub-components embedded in a more extended jet. Due to the fact that the sub-components have different spectral indices it is possible to determine which part of each image corresponds to the same source sub-component. Our main finding is that one of the images, B, looks very different to the others, there being no obvious division into separate sub-components and the image being apparently both broader and smoother. This is a consequence we believe of scatter-broadening in the ISM of the lensing galaxy. The large number of multiply-imaged source sub-components also provide an abundance of modelling constraints and we have attempted to fit an SIE+external shear model to the data, as well as utilising the novel method of Evans & Witt. It proves difficult in both cases, however, to obtain a satisfactory fit which strongly suggests the presence of sub-structure in the mass distribution of the lensing galaxy, perhaps of the kind that is predicted by CDM theories of structure formation.Comment: Accepted for publication in MNRAS. 13 pages, 8 figures. Full resolution versions of Figures 1, 2, 3, 4 and 5 are obtainable from ftp://ftp.jive.nl/pub/biggs/0128_highres.tar.g

The Cosmic Lens All-Sky Survey (CLASS) is an international collaborative programme which has obtained high-resolution radio images of over 10 000 flat-spectrum radio sources in order to create the largest and best-studied statistical sample of radio-loud gravitationally lensed systems. With this survey, combined with detailed studies of the lenses found therein, constraints can be placed on the expansion rate, matter density and dark energy (e.g. cosmological constant, quintessence) content of the Universe that are complementary to and independent of those obtained through other methods. CLASS is aimed at identifying lenses where multiple images are formed from compact flat-spectrum radio sources, which should be easily identifiable in the radio maps. Because CLASS is radio-based, dust obscuration in lensing galaxies is not a factor, and the relative insensitivity of the instrument to environmental conditions (e.g. weather, 'seeing') leads to nearly uniform sensitivity and resolution over the entire survey. In four observing 'seasons' from 1994 to 1999, CLASS has observed 13 783 radio sources with the Very Large Array (VLA) at 8.4 GHz in its largest 'A'-configuration (0.2-arcsec resolution). When combined with the Jodrell Bank VLA Astrometric Survey (JVAS), the CLASS sample contains over 16 000 images. A complete sample of 11 685 sources was observed, selected to have a flux density of at least 30 mJy in the Green Bank Survey (GB6) catalogue at 4.85 GHz (spanning the declination range 0• and |b| 10 • , excluding the Galactic plane) and a spectral index α −0.5 between the NRAO-VLA Sky Survey (NVSS) at 1.4 GHz and the GB6. A typical 30-s CLASS snapshot reached an rms noise level of 0.4 mJy. So far, CLASS has found 16 new gravitational lens systems, and the JVAS/CLASS survey contains a total of 22 lenses. The follow-up of a small number of candidates using the VLA, MERLIN, the Very Long Baseline Array (VLBA) and optical telescopes is still underway. In this paper, we present a summary of the CLASS observations, the JVAS/CLASS sample, and statistics on sub-samples of the survey. An accompanying paper presents the lens candidate selection, and in a third paper the implications for cosmology are discussed.