19 research outputs found
Correlation between Compact Radio Quasars and Ultra-High Energy Cosmic Rays
Some proposals to account for the highest energy cosmic rays predict that
they should point to their sources. We study the five highest energy events
(E>10^20 eV) and find they are all aligned with compact, radio-loud quasars.
The probability that these alignments are coincidental is 0.005, given the
accuracy of the position measurements and the rarity of such sources. The
source quasars have redshifts between 0.3 and 2.2. If the correlation pointed
out here is confirmed by further data, the primary must be a new hadron or one
produced by a novel mechanism.Comment: 8 pages, 3 tables, revtex. with some versions of latex it's necessary
to break out the tables and latex them separately using article.sty rather
than revtex.st
Sampled-Current Voltammetry at Microdisk Electrodes: Kinetic Information from Pseudo Steady State Voltammograms
Head-Tail Galaxies: Beacons of High-Density Regions in Clusters
Using radio data at 1.4 GHz from the ATCA we identify five head-tail (HT)
galaxies in the central region of the Horologium-Reticulum Supercluster (HRS).
Physical parameters of the HT galaxies were determined along with substructure
in the HRS to probe the relationship between environment and radio properties.
Using a density enhancement technique applied to 582 spectroscopic measurements
in the 2 degree x 2 degree region about A3125/A3128, we find all five HT
galaxies reside in regions of extremely high density (>100 galaxies/Mpc^3). In
fact, the environments surrounding HT galaxies are statistically denser than
those environments surrounding non-HT galaxies and among the densest
environments in a cluster. Additionally, the HT galaxies are found in regions
of enhanced X-ray emission and we show that the enhanced density continues out
to substructure groups of 10 members. We propose that it is the high densities
that allow ram pressure to bend the HT galaxies as opposed to previously
proposed mechanisms relying on exceptionally high peculiar velocities.Comment: 12 pages, 5 figures, accepted in MNRA
The validity of predicting the basal metabolic rate of young Australian men and women
The validity of predicting the basal metabolic rate of young Australian men and wome
Hubble Space Telescope imaging of compact steep spectrum radio sources
We present Hubble Space Telescope WFPC2 images taken through a broad red filter (F702W) of 30 Third Cambridge Catalog compact steep spectrum (CSS) radio sources. We have overlaid radio maps taken from the literature on the optical images to determine the radio-optical alignment and to study detailed correspondence. All CSS sources for which the relative orientation between the optical and radio can be measured display good alignment between the optical and radio emission down to the lowest redshift in the sample, z similar to 0.1. The alignment effect does not occur at this relatively low redshift for the large-scale 3CR radio sources, which tend to show a significant alignment only at z > 0.6, as shown by McCarthy et al., Chambers et al., and de Koff et al. We find candidates for optical synchrotron hot spots in 3C 213.1 and 3C 380 and an optical jet in 3C 346
Decompression through clockwise P-T path: implications for early N-S shortening orogenesis in the Mesoproterozoic Mt Isa Inlier (NE Australia)
Mesoproterozoic terranes of the Australian craton exhibit complex tectonometamorphic histories that are generally considered to result from low-pressure/high-temperature (LPHT) metamorphism with an anticlockwise pressure (P)–temperature (T) path. Yet studies regarding the nature of the P–T history and tectonic regime that led to such a LPHT signature have been quite limited. A foliation intersection/inflection axes preserved in the porphyroblast (FIA) analysis combined with textural relationships and P–T pseudosections, using a key locality of the Eastern Fold Belt of the Mt Isa Inlier, has resolved the cause of the LPHT signature in this region. Two periods of porphyroblast growth have been distinguished using a change in FIA trends with time; the first formed during N–S shortening and the second during W–E shortening orogenesis (D1 & D2, respectively). Significantly, D1 porphyroblasts preserving W–E FIAs are minerals of the Barrovian style, whereas D2 formed porphyroblasts preserving N–S FIAs are Buchan in style. This is consistent with the emplacement of the Williams/Naraku Batholiths after D1 around the onset of D2. Higher-pressure garnet cores, that can be modelled in MnNCKFMASH P–T pseudosections, preserve early W–E FIA and formed during D1. This was followed by decompression and then LPHT metamorphism and deformation during which N–S FIAs were preserved within porphyroblasts. This is supported by the presence of at least two generations of staurolite that crystallized before and after andalusite/cordierite. Middle to upper amphibolite facies metamorphic conditions occurred during D1 with crustal thickening followed by near-isothermal decompression leading to LPHT conditions. This was followed by D2 and a second period of middle to upper amphibolite facies metamorphism that obliterated and/or obscured the tectonometamorphic signature of D1 in the matrix of most rocks
Chocolate Bars Based on Human Nutritional Requirements
International audienceKey Points * The nutritional value of chocolate bars should be based on the nutritional value of the low energy dense late Paleolithic human diet to help reduce mental ill health, obesity, and other postprandial insults. * Current chocolate bars have a high energy density (>2 kcal/g). * Cocoa can be sweetened by the addition of calorie-free Purefruit™ (Tate & Lyle) monk fruit ( Siraitia grosvenorii ) extract. PUREFRUIT™ is approximately 200 times sweeter than sugar and has exceptional stability. * The energetic cost of the assimilation of chocolate can be increased by increasing its protein and fibre content. * Self-assembled, water-filled, edible nanotubes that self-organise into a more complex structure, possibly a 3D network of nanocellulose, could be incorporated into chocolate bars to lower their energy density to <1.6 kcal/g. * Durethan® KU 2-2601 packaging film enables the water content of chocolate bars to be increased without reducing product shelf life. * Aquatic biotechnology can provide all the nutrients needed to make chocolate really nutritious