672 research outputs found
Demonstration by immunoblotting of heterogeneity in the autoantibody response directed against fat cells in Graves' disease
AbstractGuinea pig fat cell membranes (FCM) have been widely used in preference to thyroid membranes as a source of TSH receptors to investigate TSH receptor antibodies in Graves' disease, because FCM are ostensibly free of other thyroid antigens. However, by FCM immunoblotting we have found: (i) 8 of 10 normal sera bound to determinants at 38 and 190 kDa; (ii) 17 other determinants were recognised by 60% of Graves' or Hashimoto sera and by 20% of normal sera; (iii) three determinants at 65–90 kDa were recognised by 5 of 13 Graves' but by none of the normal or Hashimoto sera; and (iv) none of the determinants recognised appeared to be related to the TSH receptor
Radiation tails and boundary conditions for black hole evolutions
In numerical computations of Einstein's equations for black hole spacetimes,
it will be necessary to use approximate boundary conditions at a finite
distance from the holes. We point out here that ``tails,'' the inverse
power-law decrease of late-time fields, cannot be expected for such
computations. We present computational demonstrations and discussions of
features of late-time behavior in an evolution with a boundary condition.Comment: submitted to Phys. Rev.
Nonperturbative Renormalization and the QCD Vacuum
We present a self consistent approach to Coulomb gauge Hamiltonian QCD which
allows one to relate single gluon spectral properties to the long range
behavior of the confining interaction. Nonperturbative renormalization is
discussed. The numerical results are in good agreement with phenomenological
and lattice forms of the static potential.Comment: 23 pages in RevTex, 4 postscript figure
The baryonic collapse efficiency of galaxy groups in the RESOLVE and ECO surveys
We examine the z = 0 group-integrated stellar and cold baryonic (stars + cold atomic gas) mass functions (group SMF and CBMF) and the baryonic collapse efficiency (group cold baryonic to dark matter halo mass ratio) using the RESOLVE and ECO survey galaxy group catalogs and a GALFORM semi-analytic model (SAM) mock catalog. The group SMF and CBMF fall off more steeply at high masses and rise with a shallower low-mass slope than the theoretical halo mass function (HMF). The transition occurs at the group-integrated cold baryonic mass Mbary cold ~ 1011 M. The SAM, however, has significantly fewer groups at the transition mass ∼1011 M and a steeper low-mass slope than the data, suggesting that feedback is too weak in low-mass halos and conversely too strong near the transition mass. Using literature prescriptions to include hot halo gas and potential unobservable galaxy gas produces a group BMF with a slope similar to the HMF even below the transition mass. Its normalization is lower by a factor of ∼2, in agreement with estimates of warm-hot gas making up the remaining difference. We compute baryonic collapse efficiency with the halo mass calculated two ways, via halo abundance matching (HAM) and via dynamics (extended all the way to three-galaxy groups using stacking). Using HAM, we find that baryonic collapse efficiencies reach a flat maximum for groups across the halo mass range of Mhalo ~ 1011.4 - 12 M, which we label “nascent groups.” Using dynamics, however, we find greater scatter in baryonic collapse efficiencies, likely indicating variation in group hot-to-cold baryon ratios. Similarly, we see higher scatter in baryonic collapse efficiencies in the SAM when using its true groups and their group halo masses as opposed to friends-of-friends groups and HAM masses
Study of a Swiss dopa-responsive dystonia family with a deletion in GCH1: redefining DYT14 as DYT5.
OBJECTIVE: To report the study of a multigenerational Swiss family with dopa-responsive dystonia (DRD).
METHODS: Clinical investigation was made of available family members, including historical and chart reviews. Subject examinations were video recorded. Genetic analysis included a genome-wide linkage study with microsatellite markers (STR), GTP cyclohydrolase I (GCH1) gene sequencing, and dosage analysis.
RESULTS: We evaluated 32 individuals, of whom 6 were clinically diagnosed with DRD, with childhood-onset progressive foot dystonia, later generalizing, followed by parkinsonism in the two older patients. The response to levodopa was very good. Two additional patients had late onset dopa-responsive parkinsonism. Three other subjects had DRD symptoms on historical grounds. We found suggestive linkage to the previously reported DYT14 locus, which excluded GCH1. However, further study with more stringent criteria for disease status attribution showed linkage to a larger region, which included GCH1. No mutation was found in GCH1 by gene sequencing but dosage methods identified a novel heterozygous deletion of exons 3 to 6 of GCH1. The mutation was found in seven subjects. One of the patients with dystonia represented a phenocopy.
CONCLUSIONS: This study rules out the previously reported DYT14 locus as a cause of disease, as a novel multiexonic deletion was identified in GCH1. This work highlights the necessity of an accurate clinical diagnosis in linkage studies as well as the need for appropriate allele frequencies, penetrance, and phenocopy estimates. Comprehensive sequencing and dosage analysis of known genes is recommended prior to genome-wide linkage analysis
Expansion and further delineation of the SETD5 phenotype leading to global developmental delay, variable dysmorphic features, and reduced penetrance
Diagnostic exome sequencing (DES) has aided delineation of the phenotypic spectrum of rare genetic etiologies of intellectual disability (ID). A SET domain containing 5 gene (SETD5) phenotype of ID and dysmorphic features has been previously described in relation to patients with 3p25.3 deletions and in a few individuals with de novo sequence alterations. Herein, we present additional patients with pathogenic SETD5 sequence alterations. The majority of patients in this cohort and previously reported have developmental delay, behavioral/psychiatric issues, and variable hand and skeletal abnormalities. We also present an apparently unaffected carrier mother of an affected individual and a carrier mother with normal intelligence and affected twin sons. We suggest that the phenotype of SETD5 is more complex and variable than previously presented. Therefore, many features and presentations need to be considered when evaluating a patient for SETD5 alterations through DES
Magnetic Coordinate Systems
Geospace phenomena such as the aurora, plasma motion, ionospheric currents
and associated magnetic field disturbances are highly organized by Earth's main
magnetic field. This is due to the fact that the charged particles that
comprise space plasma can move almost freely along magnetic field lines, but
not across them. For this reason it is sensible to present such phenomena
relative to Earth's magnetic field. A large variety of magnetic coordinate
systems exist, designed for different purposes and regions, ranging from the
magnetopause to the ionosphere. In this paper we review the most common
magnetic coordinate systems and describe how they are defined, where they are
used, and how to convert between them. The definitions are presented based on
the spherical harmonic expansion coefficients of the International Geomagnetic
Reference Field (IGRF) and, in some of the coordinate systems, the position of
the Sun which we show how to calculate from the time and date. The most
detailed coordinate systems take the full IGRF into account and define magnetic
latitude and longitude such that they are constant along field lines. These
coordinate systems, which are useful at ionospheric altitudes, are
non-orthogonal. We show how to handle vectors and vector calculus in such
coordinates, and discuss how systematic errors may appear if this is not done
correctly
An improved method for measuring muon energy using the truncated mean of dE/dx
The measurement of muon energy is critical for many analyses in large
Cherenkov detectors, particularly those that involve separating
extraterrestrial neutrinos from the atmospheric neutrino background. Muon
energy has traditionally been determined by measuring the specific energy loss
(dE/dx) along the muon's path and relating the dE/dx to the muon energy.
Because high-energy muons (E_mu > 1 TeV) lose energy randomly, the spread in
dE/dx values is quite large, leading to a typical energy resolution of 0.29 in
log10(E_mu) for a muon observed over a 1 km path length in the IceCube
detector. In this paper, we present an improved method that uses a truncated
mean and other techniques to determine the muon energy. The muon track is
divided into separate segments with individual dE/dx values. The elimination of
segments with the highest dE/dx results in an overall dE/dx that is more
closely correlated to the muon energy. This method results in an energy
resolution of 0.22 in log10(E_mu), which gives a 26% improvement. This
technique is applicable to any large water or ice detector and potentially to
large scintillator or liquid argon detectors.Comment: 12 pages, 16 figure
All-particle cosmic ray energy spectrum measured with 26 IceTop stations
We report on a measurement of the cosmic ray energy spectrum with the IceTop
air shower array, the surface component of the IceCube Neutrino Observatory at
the South Pole. The data used in this analysis were taken between June and
October, 2007, with 26 surface stations operational at that time, corresponding
to about one third of the final array. The fiducial area used in this analysis
was 0.122 km^2. The analysis investigated the energy spectrum from 1 to 100 PeV
measured for three different zenith angle ranges between 0{\deg} and 46{\deg}.
Because of the isotropy of cosmic rays in this energy range the spectra from
all zenith angle intervals have to agree. The cosmic-ray energy spectrum was
determined under different assumptions on the primary mass composition. Good
agreement of spectra in the three zenith angle ranges was found for the
assumption of pure proton and a simple two-component model. For zenith angles
{\theta} < 30{\deg}, where the mass dependence is smallest, the knee in the
cosmic ray energy spectrum was observed between 3.5 and 4.32 PeV, depending on
composition assumption. Spectral indices above the knee range from -3.08 to
-3.11 depending on primary mass composition assumption. Moreover, an indication
of a flattening of the spectrum above 22 PeV were observed.Comment: 38 pages, 17 figure
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
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