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Neuroimaging experiments can generate impressive volumes of data and many images of the results. This is particularly true of multi-modal imaging studies that use more than one imaging technique, or when imaging is combined with other assessments. A challenge for these studies is appropriate visualisation of results in order to drive insights and guide accurate interpretations. Next-generation visualisation technology therefore has much to offer the neuroimaging community. One example is the Imperial College London Data Observatory; a high-resolution (132 megapixel) arrangement of 64 monitors, arranged in a 313 degree arc, with a 6 metre diameter, powered by 32 rendering nodes. This system has the potential for high-resolution, large-scale display of disparate data types in a space designed to promote collaborative discussion by multiple researchers and/or clinicians. Opportunities for the use of the Data Observatory are discussed, with particular reference to applications in Multiple Sclerosis (MS) research and clinical practice. Technical issues and current work designed to optimise the use of the Data Observatory for neuroimaging are also discussed, as well as possible future research that could be enabled by the use of the system in combination with eye-tracking technology.

Trailing vortices have been repeatedly shown to exhibit a remarkably robust self-similarity independent of the Reynolds number and upstream boundary conditions. The collapse of the inner-scaled circulation profiles of a trailing vortex has even been previously demonstrated for the cases of highly unsteady and turbulent vortex systems, as well as for vortices which were incompletely developed. A number of factors which contribute to and may artificially promote this self-similarity are discussed. It is shown that the amplitude of vortex “wandering” (or the random modulations in the vortex trajectory) observed in some experimental measurements are of sufficient amplitude to cause any arbitrary finite and axisymmetric flow structure to collapse with an idealized trailing vortex when scaled on inner parameters. It is further shown that, for the case of an incompletely developed wing-tip vortex, similarity in the outer core region may be an artefact of the rate of roll-up of the vortex sheet. Great care must, therefore, be taken when interpreting experimental measurements of vortex flows.

A constant-temperature anemometer has been developed which uses a single high-fidelity speaker driver as a combined signal and power amplifier. Owing to its small size and simplicity of construction, the anemometer is well suited for applications requiring a large number of channels (such as hot-wire rakes) as well as applications requiring the embedding of instrumentation within confined experimental models (such as reduced-scale wind turbine blades). The anemometer is shown to have performance characteristics similar to those of a commercial anemometer when used under its design conditions. An operating bandwidth as high as 10 kHz can be achieved, which is greater than most available time-resolved digital particle-image velocimetry systems and is shown to be sufficient to track large-scale turbulence structures in channel flow.

Objective: To study the prevalence and correlation of the following antibodies with disease activity: antineutrophil cytoplasmic antibodies (ANCA), anti-endothelial cell antibodies (AECA) and anti-epithelial cell (anti-EPI) antibodies. Patients and methods: Sera from the following patients were tested: 41 patients with ulcerative colitis, 30 patients with ulcerative colitis following restorative proctocolectomy (RPC), 30 patients with Crohn's disease, 10 disease controls, and 34 healthy controls. Results: ANCA were found in 65 patients (64%) [31 with ulcerative colitis (76%); 21 with ulcerative colitis following RPC (70%); 13 with Crohn's disease (43%)]

The streamwise velocity component is studied in fully developed turbulent channel flow for two very rough surfaces and a smooth surface at comparable Reynolds numbers. One rough surface comprises sparse and isotropic grit with a highly non-Gaussian distribution. The other is a uniform mesh consisting of twisted rectangular elements which form a diamond pattern. The mean roughness heights (±) the standard deviation) are, respectively, about 76(±42) and 145(±150) wall units. The flow is shown to be two-dimensional and fully developed up to the fourth-order moment of velocity. The mean velocity profile over the grit surface exhibits self-similarity (in the form of a logarithmic law) within the limited range of 0.04≤y/h≤0.06, but the profile over the mesh surface does not, even though the mean velocity deficit and higher moments (up to the fourth order) all exhibit outer scaling over both surfaces. The distinction between self-similarity and outer similarity is clarified and the importance of the former is explained. The wake strength is shown to increase slightly over the grit surface but decrease over the mesh surface. The latter result is contrary to recent measurements in rough-wall boundary layers. Single- and two-point velocity correlations reveal the presence of large-scale streamwise structures with circulation in the plane orthogonal to the mean velocity. Spanwise correlation length scales are significantly larger than corresponding ones for both internal and external smooth-wall flows.

The streamwise velocity statistics in fully-developed rough-wall channel flow have been investigated for the cases of two very different surface topologies with similar Reynolds numbers. The first surface consisted of a sparse and isotropic grit having a highly non-Gaussian distribution, while the second surface was covered with a uniform, anisotropic mesh comprised of twisted, rectangular elements. The flow was demonstrated to be fully-developed and two-dimensional up to the fourth moment of velocity. Though the flow over both surface types appear to exhibit a limited logarithmic region, the regions of inner and outer scaling over the mesh surface fail to overlap. The influence of the spanwise periodicity of the mesh upon the outer scaling is discussed.

In your book ‘Identity is the new money’, you say the future of money is linked to the future of identity and that biometric technology might underpin that? How?

When compared with results from other tripeptides, high yields of ammonia in the aqueous photolyses of glycylprolylglycine and alanylprolylglycine suggest that the prolyl residue can promote peptide conformations favourable for long-range electron transfer.

The photochemical lability of peptides is poorly understood, largely because of the lack of product data. In the present study, product analyses have been carried out following the photolyses in aqueous solution of selected glycyl dipeptides (Gly-Gly, DL-AIa-GIy, L-VaI-GIy, L-Pro-Gly, L-Phe-Gly, and Gly-L-Phe), L-prolyl-L-phenylalanine, and L-phenylalanyl-L-proline. Efficient deamination and decarboxylation of aliphatic dipeptides generate thermal precursors of simple amides in a photoinduced electron-transfer process involving the peptide bond. An analogous pathway in the photodegradation of phenylalanyl peptides suffers competition from other types of reaction.

Selectivity in abiotic condensations of amino acids remains controversial and stereochemically little explored. We find that competitive activated couplings of N-acyl derivatives of glycine, alanine, valine, proline and phenylalanine with binary, ternary and quaternary mixtures of amides and esters of the same group of amino acids show little selectivity among the reactants, except with respect to configuration, where a consistent and significant preference for heterochiral outcomes, mostly >80%, is observed. One possible explanation of this selectivity predicts a predisposition to homochiral coupling under conditions that would require the two carboxyl functions to be co-facial in the activated complex.

While breast-feeding provides optimal nutrition for healthy infants, maternal health, social, and/or economic factors may constrain a mother's ability to provide human milk. Formula feeding provides a safe and effective alternative source of nutrition. In response to ongoing research, formula composition is revised to more closely mimic human milk in providing essential nutrients to support optimal growth and development. During the last decade, supplementation of infant formula with ω3 long chain polyunsaturated fatty acids (LCPUFAs) has been a major focus of infant nutrition research. ω3 LCPUFAs, particularly docosahexaenoic acid (DHA), are found in extremely high concentration in photoreceptor outer segments and in cerebral cortex.

A 62-year-old female presented with a 3-week history of non-specific abdominal pain. She had a history of rectal prolapse and was awaiting rectopexy. Clinical examination revealed gross anterior abdominal wall surgical emphysema (figures 1 and 2) as well as surgical emphysema of the pararectal region on digital rectal examination. There were no signs of peritonitis. A rigid sigmoidoscopy on …

Competitive activated couplings of N-phthaloyl amino acids with amino acid dimethylamides show little selectivity among substrates in respect of their sidechains, but a consistent and significant preference for heterochiral outcomes.

The near-field tip-vortex flow structure behind an oscillating NACA 0015 wing was investigated at . For attached-flow and light-stall oscillations, a small hysteretic property existed between the pitch-up and pitch-down motion, and many of the vortex flow features were found to be qualitatively similar to those of a static wing. For deep-stall oscillations, the wing oscillations imposed a strong discrepancy in contour shapes and magnitudes between the pitch-up and pitch-down phases of the oscillation cycle. The vortex was less organized during pitch-down (as a result of leading-edge-vortex-induced massive flow separation) than during pitch-up. The tangential velocity, circulation and lift-induced drag increased progressively with the airfoil incidence, and had higher magnitudes during pitch-up than during pitch-down, while varying slightly with the downstream distance. The vortex size, however, was larger during pitch-down than during pitch-up. The axial flow was always wake-like during the deep-stall oscillation cycle. The normalized circulation within the inner region of the tip vortex also exhibited a self-similar structure, similar to that of a static wing, and was insensitive to the reduced frequency.