Supervoid Origin of the Cold Spot in the Cosmic Microwave Background

We use a WISE-2MASS-Pan-STARRS1 galaxy catalog to search for a supervoid in the direction of the Cosmic Microwave Background Cold Spot. We obtain photometric redshifts using our multicolor data set to create a tomographic map of the galaxy distribution. The radial density profile centred on the Cold Spot shows a large low density region, extending over 10's of degrees. Motivated by previous Cosmic Microwave Background results, we test for underdensities within two angular radii, 5°, and 15°. Our data, combined with an earlier measurement by Granett et al. 2010, are consistent with a large Rvoid=(192 ± 15)h−1 Mpc (2σ) supervoid with δ ≃ −0.13 ± 0.03 centered at z=0.22 ± 0.01. Such a supervoid, constituting a ∼3.5 σ fluctuation in the ΛCDM model, is a plausible cause for the Cold Spot.

Intercerebellar Coupling Contributes to Bimanual Coordination

Compared to unimanual task execution, simultaneous bimanual tapping tasks are associated with a significantly reduced intertap variability. It has been suggested that this bimanual advantage is based on the integration of timing signals which otherwise control each hand independently. Although its functional and anatomic foundations are poorly understood, functional coupling between cerebellar hemispheres might be behind this process. Because the execution of fast alternating fingertaps increases intertap variability, it is hypothesized that intercerebellar coupling is reduced in such tasks. To shed light on the functional significance of intercerebellar coupling, 14 right-handed subjects performed unimanual right, bimanual simultaneous, and bimanual alternating synchronization tasks with respect to a regular auditory pacing signal. In all conditions, within-hand intertap interval was 500 msec. Continuous neuromagnetic activity, using a 122-channel wholehead neuromagnetometer and surface electromyograms of the first dorsal interosseus muscle of both hands, were recorded. For data analysis, we used the analysis tool Dynamic Imaging of Coherent Sources, which provides a tomographic map of cerebromuscular and cerebrocerebral coherence. Analysis revealed a bilateral cerebello-thalamo-cortical network oscillating at alpha (8–12 Hz) and beta (13–24 Hz) frequencies associated with bimanual synchronization. In line with our hypothesis, coupling between cerebellar hemispheres was restricted to simultaneous task execution. This result implies that intercerebellar coupling is key for the execution of simultaneous bimanual movements. Although the criticality of a specific magneto-encephalography pattern for behavioral changes should be interpreted with caution, data suggest that intercerebellar coupling possibly represents the functional foundation of the bimanual advantage.

3D Tomographic Map of Desmosome from Frozen-hydrated Skin Sections

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.