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The aerosol‐assisted (AA)CVD reaction of titanium isopropoxide and a solution of preformed tin dioxide nanoparticles leads to the production of titanium dioxide/tin dioxide nanocomposite thin films on glass substrates. Scanning electron microscopy (SEM) studies show that film composition and morphology are linked, with larger island sizes being observed as more tin dioxide nanoparticles are incorporated into the films. Reflectance measurements performed on the nanocomposite thin films show an increase in reflection in the infrared (IR) portion of the spectrum with increased tin dioxide nanoparticle incorporation. Photocatalysis experiments indicate that the nanocomposite films are photo‐active with irradiation by 365 nm light. The nanocomposite thin films display both low‐emissivity and self‐cleaning functionalities; and as such they are multifunctional.

Combinatorial atmospheric pressure chemical vapour deposition (cAPCVD) was used to synthesise a film with mixed gradating phases from pure orthorhombic pseudo-brookite Ti3-dO4N (0.06 < d < 0.25) to interstitial N-doped anatase TiO2 on a single film. This is the first time such a mixed graduating system has been reported. The film was characterized via Raman mapping and X-ray photoelectron spectroscopy (XPS). Film thicknesses were determined by Swanepoel method manipulations of UV-visible reflectance spectra and side-on scanning electron microscopy (SEM). Using a novel flat-bed digital scanning technique, the photocatalytic activity of the film to dichloroindophenol (DCIP) degradation under 365 nm light was also mapped. This allowed for the systematic investigation on the effect of pseudo-brookite: interstitial N-doped anatase phase composition, indicating pseudo-brookite to be the more photocatalytically active material. Films synthesized by the cAPCVD route analysed in conjunction with mapping analysis tools is a shortcut to identifying numerous phases and compositions and their functional property relationships on a single film, offering a rapid method for analysis of phase-space.

A comparison between two of the best performing photocatalysts in a series of nitrogen‐ and sulfur‐doped titania visible light photocatalysts prepared by atmospheric pressure (AP)CVD is made against a sample of pure undoped titania. This study compares the ability of the samples to photo‐oxidize stearic acid and kill Escherichiacolibacteria using white light sources commonly found in UK hospitals. It is shown that both nitrogen‐ and sulfur‐doped photocatalysts are bioactive with extraordinarily similar properties though the nitrogen‐doped samples are found to perform very slightly better than the sulfur‐doped samples. These materials are suggested for use as anti‐microbial surfaces in healthcare environments and as self‐cleaning glass.

It has been possible to observe a 99.98% reduction in the viable count of colonies of E. colion a film of titanium oxynitride when exposed to 365 nm light. This film of the recently discovered Ti2.85O4N, isostructural to pseudobrookite, was grown on a glass substrate using atmospheric pressure chemical vapour deposition (APCVD).

N‐TiO2prepared by atmospheric pressure chemical vapour deposition shows visible light photocatalysis. This is to our knowledge the first example of an N‐doped anatase film with only interstitial doping. The film was prepared using a method that is entirely compatible with industrial processes for producing self‐cleaning glass.

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This study demonstrates that adult human mesenchymal cells (MSC) can be encapsulated in alginate beads with a substantially retained viability (>80%) and that a Gly-Arg-Gly-Asp-Tyr (GRGDY) derivative encourages attachment and elongation to form a dense network of cells that is required for a tissue substitute. Because the availability of autologous human material is severely limited, we used and examined the beads in this study as a proxy for larger constructs. These bead constructs were assessed using phase contrast microscopy and standard histological preparations. In addition, we used a modified MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to examine cell proliferation by dissociating the cell/alginate constructs using trisodium citrate and trypsin/EDTA. MSCs did not proliferate within the alginate-GRGDY matrix during the 2 weeks examined. These results were further substantiated by concurrent cell density measurements using a hemocytometer. In addition, the glucose consumption rate was measured and compared to that of MSCs grown in two-dimensional culture vessels, indicating steady consumption albeit at a lower level in the entrapped MSCs.

This article reviews the current literature relating to medical outpatient services. It has been produced as part of the RCP/NHS Confederation working party on outpatients departments. The article deals with surveys of patient views on outpatients, suggested ways of improving the service, and how best to accommodate teaching in this setting. An RCP booklet, ‘How user friendly is your outpatient department?', has also been produced and is available from the college.

Production of nematode-based pesticides involves the recovery of a viable nematode life stage known as the infective juvenile (IJ) from fermentation broth. Waste components to be separated from the IJs include non-IJ life stages, dead nematodes, nematode debris, spent media, and the nematode's associated bacteria. This paper reports separation characteristics of liquid cultures and suspensions of the nematodes Phasmarhabditis hermaphrodita, Steinernema feltiae, and Heterorhabditis megidis measured at small scale. Separation characteristics were determined for dead-end filtration, gravity settling and flotation. Results were used to identify large-scale recovery procedures. Separation of culture liquid by dead-end filtration of the crude fermentation broth was not possible due to rapid blinding of filters. However, nematode-water suspensions prepared by gravity settling could be concentrated using this separation method. Settling tests indicated that IJs could be efficiently separated from culture liquid by centrifugation but not by gravity settling. Examination of the effects of nematode concentration indicated an optimum concentration for gravity settling that may entail modest dilution of the fermentation broth. Flocculation of insoluble spent media in suspensions of P. hermaphrodita prevented its separation from nematodes by gravity settling. However, attachment of air bubbles to spent media allowed removal by flotation. Finally, adjustment of continuous phase density using sucrose allowed separation of non-IJ life stages, dead nematodes, and discarded cuticles from the IJs by flotation. The efficiency of this separation decreased with increasing nematode−solute contact time.

A method for the wet extrusion of human plasma-derived fibronectin–fibrinogen cables is described. Solutions of fibronectin and fibrinogen with and without sodium alginate and carboxymethylcellulose (CMC) are tested. The rheological properties of the protein solutions changed from Newtonian to shear thinning non-Newtonian in the presence of small quantities of these additives, the apparent viscosity increased, and the extrusion properties of the protein solutions improved. Cables were prepared using a capillary with a diameter of 1 mm and overall length of 18 mm. Cable diameter was reduced to about 0.5 mm by drawing using a series of rollers. Cables prepared with sodium alginate were found to have suitable properties, and those made with CMC were sticky and difficult to handle. Solutions containing no sodium alginate required a minimum total protein concentration of about 70 mg/mL for extrusion. Extruded cables were prepared with solutions containing 140 mg/mL total protein with 12.9 mg/mL alginate (high protein), and 46 mg/mL total protein with 47.6 mg/mL of sodium alginate (high alginate). The mechanical strength of the extruded cables was within the range suitable for application in tissue engineering. Extrusion of the protein solutions into cables was achieved in a coagulation bath. Cables with a mechanical strength of approximately 30 N/mm², suitable for wound repair and nerve regeneration applications, were prepared with a coagulation bath containing 0.25 M HCl, 2% CaCl2 at a pH of &lt;0.9. These cables also had a large average elongation at break of 52%, and showed an increase in cable length after breakage (permanent set) of 20%, demonstrating the potential for drawing the cables down to a fine diameter. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 295–305, 2001.

The rapid conversion of cholesterol to cholestenone by Nocardia in the presence of high proportions of water-immiscible solvent has been demonstrated. At high agitator speeds, the reaction rate was not limited by the rates of transfer of oxygen or cholesterol to the microorganisms. Using 100 g of thawed cells in 200 ml of carbon tetrachloride containing 16% (w/v) cholesterol, at 20°C cholestenone was formed at 7 g/hr. Cells could be separated easily from the organic solvent and reused. After 7 runs (69 hr) the reaction rate had fallen only to half the value for the first run.