594 research outputs found
The Integrated Sachs-Wolfe Signal from BOSS Super-Structures
Cosmic structures leave an imprint on the microwave background radiation
through the integrated Sachs-Wolfe effect. We construct a template map of the
linear signal using the SDSS-III Baryon Acoustic Oscillation Survey at redshift
0.43 < z < 0.65. We verify the imprint of this map on the Planck CMB
temperature map at the 97% confidence level and show consistency with the
density-temperature cross-correlation measurement. Using this ISW
reconstruction as a template we investigate the presence of ISW sources and
further examine the properties of the Granett-Neyrinck-Szapudi supervoid and
supercluster catalogue. We characterise the three-dimensional density profiles
of these structures for the first time and demonstrate that they are
significant structures. Model fits demonstrate that the supervoids are
elongated along the line-of-sight and we suggest that this special orientation
may be picked out by the void-finding algorithm in photometric redshift space.
We measure the mean temperature profiles in Planck maps from public void and
cluster catalogues. In an attempt to maximise the stacked ISW signal we
construct a new catalogue of super-structures based upon local peaks and
troughs of the gravitational potential. However, we do not find a significant
correlation between these structures and the CMB temperature.Comment: Updated to match journal articl
Differences in intestinal size, structure, and function contributing to feed efficiency in broiler chickens reared at geographically distant locations
The contribution of the intestinal tract to differences in residual feed intake (RFI) has been inconclusively studied in chickens so far. It is also not clear if RFI-related differences in intestinal function are similar in chickens raised in different environments. The objective was to investigate differences in nutrient retention, visceral organ size, intestinal morphology, jejunal permeability and expression of genes related to barrier function, and innate immune response in chickens of diverging RFI raised at 2 locations (L1: Austria; L2: UK). The experimental protocol was similar, and the same dietary formulation was fed at the 2 locations. Individual BW and feed intake (FI) of chickens (Cobb 500FF) were recorded from d 7 of life. At 5 wk of life, chickens (L1, n = 157; L2 = 192) were ranked according to their RFI, and low, medium, and high RFI chickens were selected (n = 9/RFI group, sex, and location). RFI values were similar between locations within the same RFI group and increased by 446 and 464 g from low to high RFI in females and males, respectively. Location, but not RFI rank, affected growth, nutrient retention, size of the intestine, and jejunal disaccharidase activity. Chickens from L2 had lower total body weight gain and mucosal enzyme activity but higher nutrient retention and longer intestines than chickens at L1. Parameters determined only at L1 showed increased crypt depth in the duodenum and jejunum and enhanced paracellular permeability in low vs. high RFI females. Jejunal expression of IL1B was lower in low vs. high RFI females at L2, whereas that of TLR4 at L1 and MCT1 at both locations was higher in low vs. high RFI males. Correlation analysis between intestinal parameters and feed efficiency metrics indicated that feed conversion ratio was more correlated to intestinal size and function than was RFI. In conclusion, the rearing environment greatly affected intestinal size and function, thereby contributing to the variation in chicken RFI observed across locations
A High-resolution Adaptive Moving Mesh Hydrodynamic Algorithm
An algorithm for simulating self-gravitating cosmological astrophysical
fluids is presented. The advantages include a large dynamic range,
parallelizability, high resolution per grid element and fast execution speed.
The code is based on a finite volume flux conservative
Total-Variation-Diminishing (TVD) scheme for the shock capturing hydro, and an
iterative multigrid solver for the gravity. The grid is a time dependent field,
whose motion is described by a generalized potential flow. Approximately
constant mass per cell can be obtained, providing all the advantages of a
Lagrangian scheme. The grid deformation combined with appropriate limiting and
smoothing schemes guarantees a regular and well behaved grid geometry, where
nearest neighbor relationships remain constant. The full hydrodynamic fluid
equations are implemented in the curvilinear moving grid, allowing for
arbitrary fluid flow relative to the grid geometry. This combination retains
all the advantages of the grid based schemes including high speed per fluid
element and a rapid gravity solver.
The current implementation is described, and empirical simulation results are
presented. Accurate execution speed calculations are given in terms of floating
point operations per time step per grid cell. This code is freely available to
the community.Comment: 53 pages including 14 figures, submitted to ApJ
Nutritional supplements, leptin, insulin and progesterone in female Australian Cashmere goats
In small ruminants, reproductive wastage due to early embryo mortality is a major industry issue because it reduces reproductive efficiency and limits productivity. In sheep, early embryo mortality appears to be caused by reductions in progesterone concentrations when animals are over-fed, but this concept has not been studied in goats. Therefore we tested whether a supplement of lupin grain affects circulating progesterone concentrations in Cashmere goats during non- breeding season. We allocated 23 females into two groups: Controls were fed to ensure maintenance of body mass (85% chaff, 15% lupins head daily); Supplemented goats were fed twice their daily requirements for maintenance. All animals were anovulatory and treated with CIDRs to supply exogenous progesterone at a relatively constant rate. Nutritional treatments lasted for 18 days, and coincided with the presence of CIDRs. Leptin and insulin concentrations were increased (p < 0.05) by supplementation, but progesterone concentrations did not significant differ between groups at any time during the experiment. We conclude that a dietary supplement that elicits major changes in energy homeostasis does not reduce progesterone concentrations in goats and is thus unlikely to affect embryo mortality
Genome-wide association studies for feedlot and growth traits in cattle
A genome wide-association study for production traits in cattle was carried out using genotype data from the 10K Affymetrix (Santa Clara, CA) and the 50K Illumina (San Diego, CA) SNP chips. The results for residual feed intake (RFI), BW, and hip height in 3 beef breed types (Bos indicus, Bos taurus, and B. indicus × B. taurus), and for stature in dairy cattle, are presented. The aims were to discover SNP associated with all traits studied, but especially RFI, and further to test the consistency of SNP effects across different cattle populations and breed types. The data were analyzed within data sets and within breed types by using a mixed model and fitting 1 SNP at a time. In each case, the number of significant SNP was more than expected by chance alone. A total of 75 SNP from the reference population with 50K chip data were significant (P < 0.001) for RFI, with a false discovery rate of 68%. These 75 SNP were mapped on 24 different BTA. Of the 75 SNP, the 9 most significant SNP were detected on BTA 3, 5, 7, and 8, with P ≤ 6.0 × 10 . In a population of Angus cattle divergently selected for high and low RFI and 10K chip data, 111 SNP were significantly (P < 0.001) associated with RFI, with a false discovery rate of 7%. Approximately 103 of these SNP were therefore likely to represent true positives. Because of the small number of SNP common to both the 10K and 50K SNP chips, only 27 SNP were significantly (P < 0.05) associated with RFI in the 2 populations. However, other chromosome regions were found that contained SNP significantly associated with RFI in both data sets, although no SNP within the region showed a consistent effect on RFI. The SNP effects were consistent between data sets only when estimated within the same breed type
Synthesis and Structural Investigation of an \u27Oxazinoquinolinespirohexadienone\u27 That Only Exists as Its Long-Wavelength Ring-Opened Quinonimine Isomer
The spirocyclic oxazinoquinolinespirohexadienone (OSHD) photochromes are computationally predicted to be an attractive target as electron deficient analogues of the perimidinespirohexadienone (PSHD) photochromes, for eventual application as photochromic photooxidants. We have found the literature method for their preparation unsuitable and present an alternative synthesis. Unfortunately the product of this synthesis is the long wavelength (LW) ring-opened quinonimine isomer of the OSHD. We have found this isomer does not close to the spirocyclic short wavelength isomer (SW) upon prolonged standing in the dark, unlike other PSHD photochromes. The structure of this long wavelength isomer was found by NMR and X-ray crystallography to be exclusively the quinolinone (keto) tautomer, though experimental cyclic voltammetry supported by our computational methodology indicates that the quinolinol (enol) tautomer (not detected by other means) may be accessible through a fast equilibrium lying far toward the keto tautomer. Computations also support the relative stability order of keto LW over enol LW over SW
Xiphodynia: A diagnostic conundrum
This paper presents 3 case reports of xiphodynia that presented to a chiropractic clinic. The paper examines aspects of xiphodynia including relevant anatomy of the xiphoid, as well as the incidence, aetiology, symptoms, diagnosis, and treatment. A brief overview of the mechanism of referred pain is presented
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