254 research outputs found
Models for the Clustering of Far-Infrared and Sub-millimetre selected Galaxies
We discuss and compare two alternative models for the two-point angular
correlation function of galaxies detected through the sub-millimetre emission
using the Herschel Space Observatory. The first, now-standard Halo Model, which
represents the angular correlations as arising from one-halo and two-halo
contributions, is flexible but complex and rather unwieldy. The second model is
based on a much simpler approach: we incorporate a fitting function method to
estimate the matter correlation function with approximate model of the bias
inferred from the estimated redshift distribution to find the galaxy angular
correlation function. We find that both models give a good account of the shape
of the correlation functions obtained from published preliminary studies of the
HerMES and H-ATLAS surveys performed using Herschel, and yield consistent
estimates of the minimum halo mass within which the sub-millimetre galaxies
must reside. We note also that both models predict an inflection in the
correlation function at intermediate angular scales, so the presence of the
feature in the measured correlation function does not unambiguously indicate
the presence of intra-halo correlations. The primary barrier to more detailed
interpretation of these clustering measurements lies in the substantial
uncertainty surrounding the redshift distribution of the sources.Comment: 5 pages, 6 figures, 1 table, accepted for publication in MNRA
Zonal Modes of Cosmic Microwave Background Temperature Maps
All-sky maps of the cosmic microwave background temperature fluctuations are
usually represented by a spherical harmonic decomposition involving modes
labelled by their degree l and order m (where -l < m < +l). The zonal modes
(i.e those with m = 0) are of particular interest because they vary only with
galactic latitude; any anomalous behaviour in them might therefore be an
indication of erroneous foreground substraction. We perform a simple
statistical analysis of the modes with low l for sky maps derived via different
cleaning procedures from the Wilkinson Microwave Anisotropy Probe (WMAP) and
show that the zonal modes provide a useful diagnostic of possible systematics.Comment: 5 pages, 4 tables, 2 figures, accepted for publication in MNRA
Genital tract abnormalities among female sex workers who douche with Lemon/Lime juice in Nigeria
Vaginal douche products have been associated with cervical cancer. We examined female sex workers (FSWs) in Nigeria who douche with lemon or lime juice and compared the findings with that of nonusers. We obtained Pap smears and performed colposcopy of the vulva, vagina and cervix. A total of 374 FSWs comprising 81 Lemon users (LUs) and 293 non lemon users (NLUs) were examined. Their mean age was 27.8 ± 6.7 (range 16-63) years. At colposcopy, 17(4.5%) had genital warts [LUs 5(6.2%); NLUs 12(4.1%); p=0.43], 61(16.3%) had suspectedsquamous intraepithelial lesions (SILs) [LUs 17(21.0%); NLUs 44(15.0%); p=0.20] and 65(17.4%) had other findings. Pap smear cytology showed that 87(24.6%) had SILs [LUs 26(33.3%); NLUs 61(22.1%); p=0.03]. Lemon/lime use was associated with cervical dysplasia after controlling for HIV status (Adjusted OR=1.8; 95% CI,1.0-3.0). Our data suggests an association between the practice of douching with citrus juice and cervical dysplasia (Afr J Reprod Health 2009; 13[1]:37-45)
Hydrocarbon reservoir volume estimation using 3-D seismic and well log data over an X-field, Niger Delta Nigeria
Statistical Characterization of Temperature Patterns in Anisotropic Cosmologies
We consider the issue of characterizing the coherent large-scale patterns
from CMB temperature maps in globally anisotropic cosmologies. The methods we
investigate are reasonably general; the particular models we test them on are
the homogeneous but anisotropic relativistic cosmologies described by the
Bianchi classification. Although the temperature variations produced in these
models are not stochastic, they give rise to a "non-Gaussian" distribution of
temperature fluctuations over the sky that is a partial diagnostic of the
model. We explore two methods for quantifying non-Gaussian and/or
non-stationary fluctuation fields in order to see how they respond to the
Bianchi models.We first investigate the behavior of phase correlations between
the spherical harmonic modes of the maps. Then we examine the behavior of the
multipole vectors of the temperature distribution which, though defined in
harmonic space, can indicate the presence of a preferred direction in real
space, i.e. on the 2-sphere. These methods give extremely clear signals of the
presence of anisotropy when applied to the models we discuss, suggesting that
they have some promise as diagnostics of the presence of global asymmetry in
the Universe.Comment: 14 pages, 10 figures, 4 tables, accepted by MNRA
The Siren Site and the Long Transition from Archaic to Late Prehistoric Lifeways on the Eastern Edwards Plateau of Central Texas
On behalf of the Texas Department of Transportation (TxDOT), SWCA Environmental Consultants (SWCA) conducted testing and data recovery investigations at the Siren site (41WM1126), a prehistoric multi-component site in the Interstate Highway 35 right-of-way along the South Fork of the San Gabriel River in Williamson County, Texas. The work was done to fulfill TxDOT’s compliance obligations under the National Historic Preservation Act and the Antiquities Code of Texas. The testing investigations were conducted under Antiquities Permit 3834, and the subsequent data recovery was under Permit 3938. Kevin Miller served as Principal Investigator on both permits. Though the site extends far beyond the area of potential effects both horizontally and vertically, the investigations focused on Late Archaic and Late Prehistoric components within a relatively limited area that would be subject to project impacts. The investigations were conducted in February 2006.
The investigations identified five isolable components that were intermittently laid down from approximately 2600 to 900 years ago. A substantial Late Prehistoric Austin phase occupation is represented by Scallorn projectile points, stone tools, burned rock, faunal materials, and radiocarbon dates from cooking features. The component feature assemblage includes a cluster of discrete, well-preserved burned rock features that range from small fire-cracked rock concentrations to a large, slab-lined feature that dominates the cluster.
The underlying components include four cultural strata representing a series of phases in the final millennium or so of the long Archaic period. These components span approximately 2600 to 1500 b.p., though earlier, deeply buried components were also noted on the site. These deeper deposits were not the focus of the investigations, however, since they would not be affected by the project. The Archaic components revealed a suite of small side-notched dart points such as Ensor, Fairland, and Frio, as well as many earlier broad-bladed styles such as Castroville, Montell, Marshall, and Pedernales. These robust components contained numerous burned rock features of varying size and function, abundant tools, well-preserved faunal materials, macrobotanical remains including geophytes from several earth ovens, and a large suite of radiocarbon dates. The features include an incipient burned rock midden, burned rock clusters, a debitage reduction area, a biface cache, slab-lined hearths, basin-shaped hearths, and small circular hearths. The distributions of artifacts and features within the Archaic components across the excavation blocks showed significant variations. These differences reflect sequential components that provide a view of diachronic trends in technology, subsistence, economy, and a suite of other behaviors and activities during the long transition from Archaic to Late Prehistoric adaptations.
As previously determined by the testing excavations and further substantiated by the data recovery investigations, the Siren site, most notably the Late Archaic and Late Prehistoric components, is eligible for the National Register of Historic Places under Criterion D, 36 CFR 60.4, and eligible for State Archeological Landmark designation under Criteria 1 and 2 of the Rules of Practice and Procedure for the Antiquities Code of Texas, 13 TAC 26.8. The excavations and subsequent analysis have mitigated the adverse effects of the bridge construction by recovering the vast majority of the affected components within the area of potential effect. No further archaeological work is recommended. Portions of the site outside the area of potential effects have not been fully evaluated, and any future impacts beyond the mitigated areas warrant further assessment
The dynamics of human body weight change
An imbalance between energy intake and energy expenditure will lead to a
change in body weight (mass) and body composition (fat and lean masses). A
quantitative understanding of the processes involved, which currently remains
lacking, will be useful in determining the etiology and treatment of obesity
and other conditions resulting from prolonged energy imbalance. Here, we show
that the long-term dynamics of human weight change can be captured by a
mathematical model of the macronutrient flux balances and all previous models
are special cases of this model. We show that the generic dynamical behavior of
body composition for a clamped diet can be divided into two classes. In the
first class, the body composition and mass are determined uniquely. In the
second class, the body composition can exist at an infinite number of possible
states. Surprisingly, perturbations of dietary energy intake or energy
expenditure can give identical responses in both model classes and existing
data are insufficient to distinguish between these two possibilities. However,
this distinction is important for the efficacy of clinical interventions that
alter body composition and mass
Measurements of neutrino oscillation in appearance and disappearance channels by the T2K experiment with 6.6 x 10(20) protons on target
111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee commentsWe thank the J-PARC staff for superb accelerator performance and the CERN NA61/SHINE Collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC, and CFI, Canada; CEA and CNRS/IN2P3, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; RSF, RFBR and MES, Russia; MINECO and ERDF funds, Spain; SNSF and SER, Switzerland; STFC, UK; and the U. S. Deparment of Energy, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK, and the Emerald High Performance Computing facility in the Centre for Innovation, UK. In addition, participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; and DOE Early Career program, USA
Measurement of the electron neutrino charged-current interaction rate on water with the T2K ND280 pi(0) detector
10 pages, 6 figures, Submitted to PRDhttp://journals.aps.org/prd/abstract/10.1103/PhysRevD.91.112010© 2015 American Physical Society11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PR
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