Tuning properties of radial phantom motion aftereffects

AbstractMotion aftereffects are normally tested in regions of the visual field that have been directly exposed to motion (local or concrete MAEs). We compared concrete MAEs with remote or phantom MAEs, in which motion is perceived in regions not previously adapted to motion. Our aim was to study the spatial dependencies and spatiotemporal tuning of phantom MAEs generated by radially expanding stimuli. For concrete and phantom MAEs, peripheral stimuli generated stronger aftereffects than central stimuli. Concrete MAEs display temporal frequency tuning, while phantom MAEs do not show categorical temporal frequency or velocity tuning. We found that subjects may use different response strategies to determine motion direction when presented with different stimulus sizes. In some subjects, as adapting stimulus size increased, phantom MAE strength increased while the concrete MAE strength decreased; in other subjects, the opposite effects were observed. We hypothesise that these opposing findings reflect interplay between the adaptation of global motion sensors and local motion sensors with inhibitory interconnections

Management of Vertisols in sub-Saharan Africa. Proceedings of a conference

Presents papers and abstracts on the management of vertisols in sub-Saharan Africa and other parts of the world. Overviews the importance, distribution, agroclimatology and properties of vertisols and the Indian Vertisol technology experience. Reviews resource assessment and management and highlights inter-institutional modes of operation and networking concepts in Vertisol research and development

An NMR-based nanostructure switch for quantum logic

We propose a nanostructure switch based on nuclear magnetic resonance (NMR) which offers reliable quantum gate operation, an essential ingredient for building a quantum computer. The nuclear resonance is controlled by the magic number transitions of a few-electron quantum dot in an external magnetic field.Comment: 4 pages, 2 separate PostScript figures. Minor changes included. One reference adde

Burkholderia multivorans septicemia in a pediatric liver transplant patient

“Cepacia syndrome”, caused by Burkholderia cepacia complex and often associated with cystic fibrosis, carries a high mortality rate. It is rare for Burkholderia multivorans, a species within the B. cepacia complex, to cause cepacia syndrome even among patients with cystic fibrosis. This is the first reported fatal case of cepacia syndrome caused by B. multivorans occurring in a pediatric liver transplant recipient who does not have cystic fibrosis. We describe the unique characteristics of this pathogen among the non–cystic fibrosis population and the importance of early recognition and treatment

Geotextile behavior relevant to filtering low density suspended organic particles

Presented at the 8th International Geosynthetics Conference. Yokohama, Japan.This paper describes experiments on the feasibility of using geotextiles to filter organics from runoff and combined sewer overflows. A horizontal flow permittivity test apparatus was used as a prototype to test 15cm x 20cm coupons. Non-woven, needle-punched products supported both depth (interior) and cake(surface) filtration modes. Crushed anthracite in the #100-#200 mesh range was used as an inert, replicable analogue of low density, irregularly shaped suspended particles. The AOS detected with this material differs from that measured with standard media, indicating different interaction with the geotextile pore structure.Drag forces maintained a cake on the upstream face of the filter even at low hydraulic gradients. The permittivity decreased as this coating thickened. When flow ceased, the organic cake sloughed off the upstream face of the coupon. Measurements made after several doses showed recovery of much of the original permittivity, with the loss in hydraulic capacity attributed to embedment of particles in the matrix