2,584 research outputs found
Factorization of e+e- Event Shape Distributions with Hadronic Final States in Soft Collinear Effective Theory
We present a new analysis of two-jet event shape distributions in soft
collinear effective theory. Extending previous results, we observe that a large
class of such distributions can be expressed in terms of vacuum matrix elements
of operators in the effective theory. We match these matrix elements to the
full theory in the two-jet limit without assuming factorization of the complete
set of hadronic final states into independent sums over partonic collinear and
soft states. We also briefly discuss the relationship of this approach to
diagrammatic factorization in the full theory.Comment: 21 pages. Journal version. Defined an explicit thrust axis operator;
clarified meaning of a delta function operato
Magnetic helicity in magnetohydrodynamic turbulence with a mean magnetic field
A computational investigation of magnetic helicity of the fluctuatingmagnetic fieldHm in ideal and freely decaying three‐dimensional (3‐D) magnetohydrodynamics (MHD) in the presence of a uniform mean magnetic field is performed. It is shown that for ideal 3‐D MHDHm, which is a rugged invariant in the absence of a mean magnetic field [Frisch et al., J. Fluid Mech. 77, 796 (1975)], decays from its initial value and proceeds to oscillate about zero. The decay of Hm is shown to result from the presence of a new ‘‘generalized’’ helicity invariant, which includes contributions from the uniform magnetic field. The loss of invariance of Hm will diminish the effects of inverse transfer of Hm on freely decaying turbulence. This is demonstrated in a discussion of the selective decay relaxation process
An Overview of EXPRESS Rack, Microgravity Science Glovebox, and Sub-rack Facilities for Materials Science Research
No abstract availabl
Using Structure from Motion Mapping to Record and Analyze Details of the Colossal Hats (Pukao) of Monumental Statues on Rapa Nui (Easter Island)
Structure from motion (SfM) mapping is a photogrammetric technique that offers a cost-effective means of creating three-dimensional (3-D) visual representations from overlapping digital photographs. The technique is now used more frequently to document the archaeological record. We demonstrate the utility of SfM by studying red scoria bodies known as pukao from Rapa Nui (Easter Island, Chile). We created 3-D images of 50 pukao that once adorned the massive statues (moai) of Rapa Nui and compare them to 13 additional pukao located in Puna Pau, the island’s red scoria pukao quarry. Through SfM, we demonstrate that the majority of these bodies have petroglyphs and other surface features that are relevant to archaeological explanation and are currently at risk of continued degradation
The Pukao of Rapa Nui (Easter Island, Chile)
Structure from motion (SfM) mapping is a photogrammetric technique that offers a cost-effective means of creating three-dimensional visual representations from overlapping digital photographs. The technique has seen increasing uses for documenting the archaeological record. We demonstrate the utility of SfM through a study of the form of red scoria bodies known as pukao from Rapa Nui (Easter Island, Chile). We study 50 pukao that once adorned the massive statues (moai) of Rapa Nui, and compare them to 13 additional pukao located in Puna Pau: the island’s red scoria pukao quarry. Through SfM, we demonstrate that the majority of these bodies have petroglyphs and other surface features that are relevant to archaeological explanation and are currently at risk of continued degradation
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Identification of novel transcripts and peptides in developing murine lens.
We previously investigated the transcriptome and proteome profiles of the murine ocular lens at six developmental time points including two embryonic (E15 and E18) and four postnatal time points (P0, P3, P6, and P9). Here, we extend our analyses to identify novel transcripts and peptides in developing mouse lens. We identified a total of 9,707 novel transcripts and 325 novel fusion genes in developing mouse lens. Additionally, we identified 13,281 novel alternative splicing (AS) events in mouse lens including 6,990 exon skipping (ES), 2,447 alternative 3' splice site (A3SS), 1,900 alternative 5' splice site (A5SS), 1,771 mutually exclusive exons (MXE), and 173 intron retention (IR). Finally, we integrated our OMIC (Transcriptome and Proteome) datasets identifying 20 novel peptides in mouse lens. All 20 peptides were validated through matching MS/MS spectra of synthetic peptides. To the best of our knowledge, this is the first report integrating OMIC datasets to identify novel peptides in developing murine lens
Beneath the beard : do facial morphometrics influence the strength of judgments of men's beardedness?
This study was supported by a University of Queensland Postdoctoral Research Fellowship awarded to BJWD.Converging evidence suggests men's beards, like many androgen-dependent masculine secondary sexual traits, communicate masculinity and dominance intra-sexually while effects of men's beardedness on attractiveness ratings are more equivocal. Beards may enhance perceived masculinity and dominance via amplifying aspects of underlying craniofacial masculinity, particularly the size of the lower face and jaw. Here we tested these predictions across two studies. In Study 1, we tested how three facial metrics - objectively measured craniofacial masculinity, facial-width-to-height ratio (fWHR), and jaw size - calculated while clean-shaven impacted on ratings of attractiveness, masculinity and dominance of 37 men photographed when clean-shaven and with full beards. Results showed that beards exerted significant and positive effects on masculinity, dominance and to a lesser extent attractiveness. However, fWHR did not significantly interact with beardedness to influence the directions of any of the ratings, and while some linear and nonlinear interactions were significant between objective craniofacial masculinity and beardedness as well as between jaw size and beardedness, they tended to be subtle and dwarfed by the large main effect of beardedness on perceptual ratings. In Study 2, we measured ratings of attractiveness, masculinity and dominance for composite clean-shaven and bearded stimuli experimentally manipulated in facial shape to represent ±50% the shape of a beard, essentially manipulating the size of the lower face and jaw of the stimuli. We found a strong main effect whereby bearded stimuli enhanced dominance and masculinity ratings over clean-shaven stimuli. Increasing the size of the lower face and jaw augmented ratings of masculinity and dominance in clean-shaven stimuli but did not exert strong effects within bearded stimuli. Attractiveness ratings were highest for bearded faces with smaller jaws followed by bearded and clean-shaven faces with larger jaws and lowest for clean-shaven faces with small jaws. Taken together, our findings suggest that beards exert main effects on masculinity and dominance possibly by amplifying male typical facial shape. Attractiveness ratings of facial hair may reflect a compromise between overly dominant looking faces with larger jaws and the additive effects beardedness has on these ratings.PostprintPeer reviewe
Carbon-Enhanced Metal-Poor Stars. III. Main-Sequence Turn-Off Stars from the SDSS/SEGUE Sample
The chemical compositions of seven Carbon-Enhanced Metal-Poor (CEMP) turn-off
stars are determined from high-resolution spectroscopy. Five of them are
selected from the SDSS/SEGUE sample of metal-poor stars. The effective
temperatures of these objects are all higher than 6000 K, while their
metallicities, parametrized by [Fe/H], are all below -2. Six of our program
objects exhibit high abundance ratios of barium ([Ba/H]> +1), suggesting large
contributions of the products of former AGB companions via mass transfer across
binary systems. Combining our results with previous studies provides a total of
20 CEMP main-sequence turn-off stars for which the abundances of carbon and at
least some neutron-capture elements are determined. Inspection of the [C/H]
ratios for this sample of CEMP turn-off stars show that they are generally
higher than those of CEMP giants; their dispersion in this ratio is also
smaller. We take these results to indicate that the carbon-enhanced material
provided from the companion AGB star is preserved at the surface of turn-off
stars with no significant dilution. In contrast, a large dispersion in the
observed [Ba/H] is found for the sample of CEMP turn-off stars, suggesting that
the efficiency of the s-process in very metal-poor AGB stars may differ greatly
from star to star. Four of the six stars from the SDSS/SEGUE sample exhibit
kinematics that are associated with membership in the outer-halo population, a
remarkably high fraction.Comment: 45 pages, 10 figures, 10 tables, Astrophysical Journal, in pres
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