830 research outputs found
A scale-dependent cosmology for the inhomogeneous Universe
A scale-dependent cosmology is proposed in which the Robertson-Walker metric
and the Einstein equation are modified in such a way that , and
the age of the Universe all become scale-dependent. Its implications on the
observational cosmology are discussed.Comment: 7 pages, in RevTex. To be appeared in TAUP '9
Evaluation of fermented whole crop wheat and barley feeding on growth performance, nutrient digestibility, faecal volatile fatty acid emission, blood constituents, and faecal microbiota in growing pigs
This study was conducted to determine the effects of feeding diets with fermented whole crop wheat (FWW) and fermented whole crop barley (FWB) on growth performance, nutrient digestibility, blood constituents, faecal volatile fatty acid (VFA) emission and faecal microbiota in growing pigs. A total of 200 growing pigs were randomly allotted to five treatments with eight replicates per treatment and five pigs per replicate. Dietary treatments consisted of i) CON (basal diet), ii) 0.5% FWW (CON + 0.5% fermented whole crop wheat), iii) 1.0% FWW (CON + 1.0% fermented whole crop wheat), iv) 0.5% FWB (CON + 0.5% fermented whole crop barley), and v) 1.0% FWB (CON + 1.0% fermented whole crop barley). The digestibility of total dietary fibre was significantly higher in pigs fed FWW diets. The faecal emissions of VFA of pigs fed the fermented treatments was increased significantly compared with CON. Concentrations of cortisol and triglyceride in blood of pigs fed 1.0% FWW were significantly lower than pigs fed CON diets. The pigs fed 1.0% FWB diets had a significantly decreased level of total cholesterol in blood compared with CON. In conclusion, the current results indicated that diets supplemented with FWW and FWB could increase faecal VFA emission and reduce concentration of triglyceride and cortisol, while 0.5% and 1.0% FWW had no negative effects on growth performance, and could increase digestibility of dietary fibre in growing pigs.Keywords:Â Dietary fibre, faecal short-chain fatty acid emissions, fermented feed, serum parameter, swin
Astrophysical Tests of Modified Gravity: A Screening Map of the Nearby Universe
Astrophysical tests of modified modified gravity theories in the nearby
universe have been emphasized recently by Hui, Nicolis and Stubbs (2009) and
Jain and VanderPlas (2011). A key element of such tests is the screening
mechanism whereby general relativity is restored in massive halos or high
density environments like the Milky Way. In chameleon theories of gravity,
including all f(R) models, field dwarf galaxies may be unscreened and therefore
feel an extra force, as opposed to screened galaxies. The first step to study
differences between screened and unscreened galaxies is to create a 3D
screening map. We use N-body simulations to test and calibrate simple
approximations to determine the level of screening in galaxy catalogs. Sources
of systematic errors in the screening map due to observational inaccuracies are
modeled and their contamination is estimated. We then apply our methods to
create a map out to 200 Mpc in the Sloan Digital Sky Survey footprint using
data from the Sloan survey and other sources. In two companion papers this map
will be used to carry out new tests of gravity using distance indicators and
the disks of dwarf galaxies. We also make our screening map publicly available.Comment: 21 pages, 10 figure
Quantifying the levitation picture of extended states in lattice models
The behavior of extended states is quantitatively analyzed for two
dimensional lattice models. A levitation picture is established for both
white-noise and correlated disorder potentials. In a continuum limit window of
the lattice models we find simple quantitative expressions for the extended
states levitation, suggesting an underlying universal behavior. On the other
hand, these results point out that the Quantum Hall phase diagrams may be
disorder dependent.Comment: 5 pages, submitted to PR
Safety and efficacy of upadacitinib in patients with active ankylosing spondylitis and an inadequate response to nonsteroidal antiinflammatory drug therapy: one-year results of a double-blind, placebo-controlled study and open-label extension
Objective To report the efficacy and safety of upadacitinib through 1 year in patients with ankylosing spondylitis (AS). Methods In the SELECT-AXIS 1 study, adults with active AS and an inadequate response to nonsteroidal antiinflammatory drugs were randomized to receive upadacitinib 15 mg once daily or placebo. At week 14, patients who had been randomized to receive placebo were switched to upadacitinib, and all patients continued in the open-label extension and received upadacitinib up to week 104; interim data up to week 64 are reported herein. Results Of 187 patients, 178 completed week 14 on study drug and entered the open-label extension. Similar proportions of patients in either group (continuous upadacitinib or placebo-to-upadacitinib) achieved Assessment of SpondyloArthritis international Society 40% response (ASAS40) or Ankylosing Spondylitis Disease Activity Score (ASDAS) showing low disease activity at week 64: >= 70% of patients achieved these end points based on nonresponder imputation (NRI) and >= 81% based on as-observed analyses. Furthermore, >= 34% (NRI) and >= 39% (as-observed analysis) achieved ASDAS showing inactive disease or ASAS showing partial remission at week 64. Mean changes from baseline (week 0) to week 64 in pain, function, and inflammation showed consistent improvement or sustained maintenance through the study. Among 182 patients receiving upadacitinib (237.6 patient-years), 618 adverse events (260.1 per 100 patient-years) were reported. No serious infections, major adverse cardiovascular events, venous thromboembolic events, gastrointestinal perforation, or deaths were reported. Conclusion Upadacitinib 15 mg once daily showed sustained and consistent efficacy over 1 year. Patients who switched from placebo to upadacitinib at week 14 showed similar efficacy versus those who received continuous upadacitinib.Pathophysiology and treatment of rheumatic disease
Cosmological parameters from SDSS and WMAP
We measure cosmological parameters using the three-dimensional power spectrum
P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in
combination with WMAP and other data. Our results are consistent with a
``vanilla'' flat adiabatic Lambda-CDM model without tilt (n=1), running tilt,
tensor modes or massive neutrinos. Adding SDSS information more than halves the
WMAP-only error bars on some parameters, tightening 1 sigma constraints on the
Hubble parameter from h~0.74+0.18-0.07 to h~0.70+0.04-0.03, on the matter
density from Omega_m~0.25+/-0.10 to Omega_m~0.30+/-0.04 (1 sigma) and on
neutrino masses from <11 eV to <0.6 eV (95%). SDSS helps even more when
dropping prior assumptions about curvature, neutrinos, tensor modes and the
equation of state. Our results are in substantial agreement with the joint
analysis of WMAP and the 2dF Galaxy Redshift Survey, which is an impressive
consistency check with independent redshift survey data and analysis
techniques. In this paper, we place particular emphasis on clarifying the
physical origin of the constraints, i.e., what we do and do not know when using
different data sets and prior assumptions. For instance, dropping the
assumption that space is perfectly flat, the WMAP-only constraint on the
measured age of the Universe tightens from t0~16.3+2.3-1.8 Gyr to
t0~14.1+1.0-0.9 Gyr by adding SDSS and SN Ia data. Including tensors, running
tilt, neutrino mass and equation of state in the list of free parameters, many
constraints are still quite weak, but future cosmological measurements from
SDSS and other sources should allow these to be substantially tightened.Comment: Minor revisions to match accepted PRD version. SDSS data and ppt
figures available at http://www.hep.upenn.edu/~max/sdsspars.htm
Protons in near earth orbit
The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured
by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at
an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is
parameterized by a power law. Below the geomagnetic cutoff a substantial second
spectrum was observed concentrated at equatorial latitudes with a flux ~ 70
m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated
trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure
Search for antihelium in cosmic rays
The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle
Discovery during flight STS-91 in a 51.7 degree orbit at altitudes between 320
and 390 km. A total of 2.86 * 10^6 helium nuclei were observed in the rigidity
range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper
limit on the flux ratio of antihelium to helium of < 1.1 * 10^-6 is obtained.Comment: 18 pages, Latex, 9 .eps figure
A Study of Cosmic Ray Secondaries Induced by the Mir Space Station Using AMS-01
The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle physics
experiment that will study cosmic rays in the to range and will be installed on the International Space Station
(ISS) for at least 3 years. A first version of AMS-02, AMS-01, flew aboard the
space shuttle \emph{Discovery} from June 2 to June 12, 1998, and collected
cosmic ray triggers. Part of the \emph{Mir} space station was within the
AMS-01 field of view during the four day \emph{Mir} docking phase of this
flight. We have reconstructed an image of this part of the \emph{Mir} space
station using secondary and emissions from primary cosmic rays
interacting with \emph{Mir}. This is the first time this reconstruction was
performed in AMS-01, and it is important for understanding potential
backgrounds during the 3 year AMS-02 mission.Comment: To be submitted to NIM B Added material requested by referee. Minor
stylistic and grammer change
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
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