13,577 research outputs found
Possible Suppression of Resonant Signals for Split-UED by Mixing at the LHC?
The mixing of the imaginary parts of the transition amplitudes of nearby
resonances via the breakdown of the Breit-Wigner approximation has been shown
to lead to potentially large modifications in the signal rates for new physics
at colliders. In the case of suppression, this effect may be significant enough
to lead to some new physics signatures being initially missed in searches at,
e.g., the LHC. Here we explore the influence of this `width mixing' on the
production of the nearly degenerate, level-2 Kaluza-Klein (KK) neutral gauge
bosons present in Split-UED. We demonstrate that in this particular case large
cross section modifications in the resonance region are necessarily absent and
explain why this is so based on the group theoretical structure of the SM.Comment: 10 pages, 2 figures; discussion and references adde
The effect of mechanical pre-processing and different drying methodologies on bioethanol production using the brown macroalgae Laminaria digitata ((Hudson) JV Lamouroux)
Macroalgae are capable of generating more organic carbon per hectare than terrestrial plants without requiring land, fertiliser or fresh water to grow. In addition, they avoid the food versus fuel argument as they are not a major food source in Europe. In spite of these benefits, macroalgae are not yet fully exploited as a biomass source for bioenergy or platform chemical production in Europe, with one issue being the high harvesting and processing costs. This paper considers the impact of mechanical pre-processing of Laminaria digitata combined with different drying techniques and the effect of these on downstream processing to bioethanol. Results show that mechanically screw pressing macroalgae does enhance conversion to ethanol, but only when the material contains low levels of storage carbohydrates. This occurs in freeze-dried and air-dried samples. The addition of a press aid in the mechanical pre-processing step increases ethanol yields per gramme macroalgae, but due to the presence of the unutilised press aid in the fermentation, ethanol yields were lower overall. The two main findings from this work were (1) simple mechanical processing of L. digitata provides homogenisation and pumpability of macroalgae without negatively affecting subsequent microbial conversion to ethanol. (2) At higher carbohydrate concentrations, screw pressing confers no advantage in ethanol yields over strips of unprocessed kelp, making strips the more viable conversion option for low-input, large-scale processingpublishersversionPeer reviewe
The Effect of Trait and State Disgust on Fear of God and Sin
There is a growing literature suggesting disgust plays a major role in religiosity. However, the relationships between specific domains of disgust sensitivity and general religious fundamentalism or religious scrupulosity remains unknown and a lack of experimental data prevents the drawing of causal inferences about the potential effects of disgust on religiosity. Two studies are reported that examined the relationship between specific types of disgust sensitivity (i.e., pathogen, sexual, and moral disgust) and specific religious beliefs (i.e., fear of sin and fear of God). In the first study it was found that sexual disgust and pathogen disgust were significantly correlated with fear of sin and fear of God, respectively. In the second study the experimental induction of disgust led to greater fear of sin but not to the fear of God. These findings suggest that pathogen and sexual disgust sensitivities may serve as effective mechanisms for inflated scrupulosity. Taken together the outcomes from both studies converge on a greater understanding of the 'Human Behavioral Immune System' model that can account for social behavior with the evolution of adaptive benefit and perhaps more importantly highlights the possible drivers of specific religious behavior
The azimuth structure of nuclear collisions -- I
We describe azimuth structure commonly associated with elliptic and directed
flow in the context of 2D angular autocorrelations for the purpose of precise
separation of so-called nonflow (mainly minijets) from flow. We extend the
Fourier-transform description of azimuth structure to include power spectra and
autocorrelations related by the Wiener-Khintchine theorem. We analyze several
examples of conventional flow analysis in that context and question the
relevance of reaction plane estimation to flow analysis. We introduce the 2D
angular autocorrelation with examples from data analysis and describe a
simulation exercise which demonstrates precise separation of flow and nonflow
using the 2D autocorrelation method. We show that an alternative correlation
measure based on Pearson's normalized covariance provides a more intuitive
measure of azimuth structure.Comment: 27 pages, 12 figure
Formation and structural chemistry of the unusual cyanide-bridged dinuclear species [Ru-2(NN)(2)(CN)(7)](3-)(NN=2,2 '-bipyridine or 1,10-phenanthroline)
Crystallisation of simple cyanoruthenate complex anions [Ru(NN)(CN)(4)](2) (NN = 2,2'-bipyridine or 1,10-phenanthroline) in the presence of Lewis-acidic cations such as Ln(III) or guanidinium cations results, in addition to the expected [Ru(NN)(CN)(4)](2) salts, in the formation of small amounts of salts of the dinuclear species [Ru-2(NN)(2)(CN)(7)](3). These cyanide-bridged anions have arisen from the combination of two monomer units [Ru(NN)(CN)(4)](2) following the loss of one cyanide, presumably as HCN. The crystal structures of [Nd(H2O)(5.5)][Ru-2(bipy)(2)(CN)(7)] center dot 11H(2)O and [Pr(H2O)(6)][Ru-2(phen)(2)(CN)(7)] center dot 9H(2)O show that the cyanoruthenate anions form Ru-CN-Ln bridges to the Ln(III) cations, resulting in infinite coordination polymers consisting of fused Ru(2)Ln(2)(mu-CN)(4) squares and Ru(4)Ln(2)(mu-CN)(6) hexagons, which alternate to form a one-dimensional chain. In [CH6N3](3)[Ru-2(bipy)(2)(CN)(7)] center dot 2H(2)O in contrast the discrete complex anions are involved in an extensive network of hydrogen-bonding involving terminal cyanide ligands, water molecules, and guanidinium cations. In the [Ru-2(NN)(2)(CN)(7)](3) anions themselves the two NN ligands are approximately eclipsed, lying on the same side of the central Ru-CN-Ru axis, such that their peripheries are in close contact. Consequently, when NN = 4,4'-Bu-t(2)-2,2'-bipyridine the steric bulk of the t-butyl groups prevents the formation of the dinuclear anions, and the only product is the simple salt of the monomer, [CH6N3](2)[Ru((t)Bu(2)bipy)(CN)(4)] center dot 2H(2)O. We demonstrated by electrospray mass spectrometry that the dinuclear by-product [Ru-2(phen)(2)(CN)(7)](3) could be formed in significant amounts during the synthesis of monomeric [Ru(phen)(CN)(4)](2) if the reaction time was too long or the medium too acidic. In the solid state the luminescence properties of [Ru-2(bipy)(2)(CN)(7)](3) (as its guanidinium salt) are comparable to those of monomeric [Ru(bipy)(CN)(4)](2), with a (MLCT)-M-3 emission at 581 nm
Spitzer, Near-Infrared, and Submillimeter Imaging of the Relatively Sparse Young Cluster, Lynds 988e
We present {\it Spitzer} images of the relatively sparse, low luminosity
young cluster L988e, as well as complementary near-infrared (NIR) and
submillimeter images of the region. The cluster is asymmetric, with the western
region of the cluster embedded within the molecular cloud, and the slightly
less dense eastern region to the east of, and on the edge of, the molecular
cloud. With these data, as well as with extant H data of stars
primarily found in the eastern region of the cluster, and a molecular CO
gas emission map of the entire region, we investigate the distribution of
forming young stars with respect to the cloud material, concentrating
particularly on the differences and similarities between the exposed and
embedded regions of the cluster. We also compare star formation in this region
to that in denser, more luminous and more massive clusters already investigated
in our comprehensive multi-wavelength study of young clusters within 1 kpc of
the Sun.Comment: 21 pages, 6 tables, 13 figures. Full resolution figures at:
http://astro.pas.rochester.edu/~tom/Preprints/L988e.pd
Nuclear shadowing at low Q^2
We re-examine the role of vector meson dominance in nuclear shadowing at low
Q^2. We find that models which incorporate both vector meson and partonic
mechanisms are consistent with both the magnitude and the Q^2 slope of the
shadowing data.Comment: 7 pages, 2 figures; to appear in Phys. Rev.
- âŠ