The functional anatomy of the McCollough contingent colour after-effect

We report two functional magnetic resonance imaging (fMRI) experiments which reveal a cortical network activated when perceiving coloured grids, and experiencing the McCollough effect (ME). Our results show that perception of red-black and green-black grids activate the right fusiform gyrus (area V4) plus the left and right lingual gyri, right striate cortex (V1) and left insula. The ME activated the left anterior fusiform gyrus as well as the ventrolateral prefrontal cortex, and in common with colour perception, the left insula. These data confirm the critical role of the fusiform gyrus in actual and illusory colour perception as well as revealing localized frontal cortical activation associated with the ME, which would suggest that a 'top-down' mechanism is implicated in this illusion.

High stress monitoring of prestressing tendons in nuclear concrete vessels using fibre-optic sensors

Maintaining the structural health of prestressed concrete nuclear containments is a key element in ensuring nuclear reactors are capable of meeting their safety requirements. This paper discusses the attachment, fabrication and characterisation of optical fibre strain sensors suitable for the prestress monitoring of irradiated steel prestressing tendons. The all-metal fabrication and welding process allowed the instrumented strand to simultaneously monitor and apply stresses up to 1300 MPa (80% of steel's ultimate tensile strength). There were no adverse effects to the strand's mechanical properties or integrity. After sensor relaxation through cyclic stress treatment, strain transfer between the optical fibre sensors and the strand remained at 69%. The fibre strain sensors could also withstand the non-axial forces induced as the strand was deflected around a 4.5 m bend radius. Further development of this technology has the potential to augment current prestress monitoring practices, allowing distributed measurements of short- and long-term prestress losses in nuclear prestressed-concrete vessels. © 2014 Elsevier B.V.

Can neurodegenerative disease be defined by four 'primary determinants':anatomy, cells, molecules, and morphology?

Traditional methods of describing and classifying neurodegenerative disease are based on the clinico-pathological concept supported by molecular pathological studies and defined by 'consensus criteria'. Disease heterogeneity, overlap between disorders, and the presence of multiple co-pathologies, however, have questioned the validity and status of many traditional disorders. If cases of neurodegenerative disease are not easily classifiable into distinct entities, but more continuously distributed, then a new descriptive framework may be required. This review proposes that there are four key neuropathological features of neurodegenerative disease (the 'primary determinants') that could be used to provide such a framework, viz., the anatomical pathways affected by the disease ('anatomy'), the cell populations affected ('cells'), the molecular pathology of 'signature' pathological lesions ('molecules'), and the morphological types of neurodegeneration ('morphology'). This review first discusses the limitations of existing classificatory systems and second provides evidence that the four primary determinants could be used as axes to define all cases of neurodegenerative disease. To illustrate the methodology, the primary determinants were applied to the study of a group of closely related tauopathy cases and to heterogeneity within frontotemporal lobar degeneration with TDP-43 proteinopathy (FTLD-TDP).