No / In this report, we evaluate the role of visual areas responsive to motion in the human brain in the perception of stimulus speed. We first identified and localized V1, V3A, and V5/MT+ in individual participants on the basis of blood oxygenation level-dependent responses obtained in retinotopic mapping experiments and responses to moving gratings. Repetitive transcranial magnetic stimulation (rTMS) was then used to disrupt the normal functioning of the previously localized visual areas in each participant. During the rTMS application, participants were required to perform delayed discrimination of the speed of drifting or spatial frequency of static gratings. The application of rTMS to areas V5/MT and V3A induced a subjective slowing of visual stimuli and ( often) caused increases in speed discrimination thresholds. Deficits in spatial frequency discrimination were not observed for applications of rTMS to V3A or V5/MT+. The induced deficits in speed perception were also specific to the cortical site of TMS delivery. The application of TMS to regions of the cortex adjacent to V5/MT and V3A, as well as to area V1, produced no deficits in speed perception. These results suggest that, in addition to area V5/MT+, V3A plays an important role in a cortical network that underpins the perception of stimulus speed in the human brain. / BBSRC

No / A crystal ball? A new method for crystal structure prediction combines a tailor-made force field with a density functional theory method incorporating a van der Waals correction for dispersive interactions. In a blind test, the method predicts the correct crystal structure for all four compounds, one of which is a cocrystal. The picture shows the predicted structure of one of the compounds in green and the experimental structure in blue.

Yes

No / There is increasing evidence for complexity in mortuary practices in Britain during the Roman period. One class of burials demonstrates an association between inhumation in stone sarcophagi or lead-lined coffins, 'plaster' coatings, textile shrouds and natural resins. It has been suggested that this 'package' represents a deliberate attempt at body preservation. Fragments with a resinous appearance found in one such burial from Arrington, Cambridgeshire, UK were analysed using gas-chromatography-mass spectrometry. The triterpenic compounds identified are biomarkers for the genus Pistacia and provide the first chemical evidence for an exotic resin in a mortuary context in Roman Britain. / AHRC

No / Medicines management services provided by community pharmacists have been proposed as one means to ensure that patients receive all the medicines they may benefit from in the English National Health Service. These services may also offer ways of addressing the historic under-utilization of community pharmacists' clinical skills and expertise. Medicines management services differ significantly from the dispensing and medicines sales roles traditionally associated with community pharmacy, particularly in relation to the provision for pharmacists to make recommendations to both patients and doctors about pharmacological treatment and lifestyle management. This paper describes patients' experiences of a medicines management service provided by community pharmacists for people with coronary heart disease, delivered in England. It draws on findings from semistructured, face-to-face interviews with 49 patients recruited from pilot sites delivering the service. Findings suggest that although patients cautiously welcomed the opportunity to consult with a pharmacist about their medicines, they had reservations about them making recommendations about treatment, and many still regarded the doctor as the health professional 'in charge' of their medicines. The implications of these findings are discussed in light of the developing sociological literature on pharmacy and medicines usage.

No / Fluctuations in accommodation have been shown to be correlated in the two eyes of the same subject. However, the dynamic correlation of higher-order aberrations in the frequency domain has not been studied previously. A binocular Shack-Hartmann wavefront sensor is used to measure the ocular wavefront aberrations concurrently in both eyes of six subjects at a sampling rate of 20.5 Hz. Coherence function analysis shows that the inter-ocular correlation between aberrations depends on subject, Zernike mode and frequency. For each subject, the coherence values are generally low across the resolvable frequency range (mean 0.11), indicating poor dynamic correlation between the aberrations of the two eyes. Further analysis showed that phase consistency dominates the coherence values. Monocular and binocular viewing conditions showed similar power spectral density functions.

No / The minerals involved in the formation of metazoan skeletons principally comprise glassy silica, calcium phosphate or carbonate. Because of their ancient heritage, glass sponges (Hexactinellida) may shed light on fundamental questions such as molecular evolution, the unique chemistry and formation of the first skeletal silica-based structures, and the origin of multicellular animals. We have studied anchoring spicules from the metre-long stalk of the glass rope sponge (Hyalonema sieboldi; Porifera, Class Hexactinellida), which are remarkable for their size, durability, flexibility and optical properties. Using slow-alkali etching of biosilica, we isolated the organic fraction, which was revealed to be dominated by a hydroxylated fibrillar collagen that contains an unusual [Gly-3Hyp-4Hyp] motif. We speculate that this motif is predisposed for silica precipitation, and provides a novel template for biosilicification in nature.

No / When a drop of liquid is placed on the surface of a soft material, the surface deformation and the rate of spreading of the triple contact point is dependent on the mechanical properties of the substrate. This study seeks to use drop spreading behavior to infer the mechanical properties of soft biological materials. As an illustration of the value of this technique we have compared the spreading behavior of a liquid droplet on two viscoelastic, soft materials, namely, an elastomer and a low concentration agar gel. The ratio of the mechanical properties of these soft materials obtained in this way is confirmed by atomic force microscopy (AFM) nanoindentation. By comparing the spreading behavior of a liquid on the retina with that of the same liquid on each of two viscoelastic materials, we can then estimate the elastic moduli of the retina: an estimate that is extremely difficult to carry out using AFM.

No / Tunica adventitia, the outer layer of blood vessels, is an important structural feature, predominantly consisting of collagen fibrils. This study uses pseudostatic atomic force microscopy (AFM) nanoindentation at physiological conditions to show that the distribution of indentation modulus and viscous creep for the tunica adventitia of porcine aorta and pulmonary artery are distinct. Dynamic nanoindentation demonstrates that the viscous dissipation of the tunica adventitia of the aorta is greater than the pulmonary artery. We suggest that this mechanical property of the aortic adventitia is functionally advantageous due to the higher blood pressure within this vessel during the cardiac cycle. The effects on pulsatile deformation and dissipative energy losses are discussed.

No / Since the characterization of the eye's monochromatic aberration fluctuations in 2001, the power spectrum has remained the most widely used method for analyzing their dynamics. However, the power spectrum does not capture the complexities of the fluctuations. We measured the monochromatic aberration dynamics of six subjects using a Shack-Hartmann sensor sampling at 21 Hz. We characterized the dynamics using techniques from chaos theory. We found that the attractor embedding dimension for all aberrations, for all subjects, was equal to three. The embedding lag averaged across aberrations and subjects was 0.31 +/- 0.07 s. The Lyapunov exponent of the rms wavefront error was positive for each subject, with an average value of 0.44 +/- 0.15 microm/s. This indicates that the aberration dynamics are chaotic. Implications for future modeling are discussed.