1,918 research outputs found
Response functions of an artificial Anderson atom in the atomic limit
We consider the spin and pseudospin (charge) response functions of the
exactly soluble Anderson atom model. We demonstrate, in particular, that a
deviation from the magnetic Curie-law behaviour, appropriate for a free spin
one-half, increases with increasing asymmetry and temperature. In general,
oscillator strength is transferred from the spin degrees of freedom to the
pseudospin modes. We also consider the negative-U Anderson atom and demonstrate
that the pseudospin modes are the relevant low-energy excitations in this case.
Especially, the roles of the spin and charge excitations are interchanged upon
reversal of the intrasite Coulomb repulsion, U.Comment: 23 pages, 12 figures. Accepted for publication in J. Low Temp. Phy
Disperse—a software system for design of selector probes for exon resequencing applications
Summary:Selector probes enable the amplification of many selected regions of the genome in multiplex. Disperse is a software pipeline that automates the procedure of designing selector probes for exon resequencing applications
Evaluation of the usefulness of carcass-weight, meat-percentage or identity of pig-producer in future-risk-based meat inspection
In the search for new and risk-based ways of conducting meat inspection, a pilot study was conducted with the amin of investigating whether carcass weight in combination with meat percentage, or producer-identity could be used as indicators for rejection of finisher pig carcasses
Are pinholes the cause of excess current in superconducting tunnel junctions? A study of Andreev current in highly resistive junctions
In highly resistive superconducting tunnel junctions, excess subgap current
is usually observed and is often attributed to microscopic "pinholes" in the
tunnel barrier. We have studied the subgap current in
superconductor-insulator-superconductor (SIS) and
superconductor-insulator-normal-metal (SIN) junctions. In Al/AlOx/Al junctions,
we observed a decrease of 2 orders of magnitude in the current upon the
transition from the SIS to the SIN regime, where it then matched theory. In
Al/AlOx/Cu junctions, we also observed generic features of coherent diffusive
Andreev transport in a junction with a homogenous barrier. We use the
quasiclassical Keldysh-Green function theory to quantify single- and
two-particle tunneling and find good agreement over 2 orders of magnitude in
transparency. We argue that our observations rule out pinholes as the origin of
the excess current.Comment: 4 pages, 4 figure
Anti-transglutaminase 6 antibodies in children and young adults with cerebral palsy.
Objectives. We have previously reported a high prevalence of gluten-related serological markers (GRSM) in children and young adults with cerebral palsy (CP). The majority had no enteropathy to suggest coeliac disease (CD). Antibodies against transglutaminase 6 (anti-TG6) represent a new marker associated with gluten-related neurological dysfunction. The aim of this study was to investigate the prevalence of anti-TG6 antibodies in this group of individuals with an early neurological injury resulting in CP. Materials and Methods. Sera from 96 patients with CP and 36 controls were analysed for IgA/IgG class anti-TG6 by ELISA. Results. Anti-TG6 antibodies were found in 12/96 (13%) of patients with CP compared to 2/36 (6%) in controls. The tetraplegic subgroup of CP had a significantly higher prevalence of anti-TG6 antibodies 6/17 (35%) compared to the other subgroups and controls. There was no correlation of anti-TG6 autoantibodies with seropositivity to food proteins including gliadin. Conclusions. An early brain insult and associated inflammation may predispose to future development of TG6 autoimmunity
Oxygen Ion Energization Observed At High Altitudes
We present a case study of significant heating (up to 8 keV) perpendicular to
the geomagnetic field of outflowing oxygen ions at high altitude (12 RE)
above the polar cap. The shape of the distribution functions indicates that
most of the heating occurs locally (within 0.2–0.4 RE in altitude). This
is a clear example of local ion energization at much higher altitude than
usually reported. In contrast to many events at lower altitudes, it is not
likely that the locally observed wave fields can cause the observed ion
energization. Also, it is not likely that the ions have drifted from some
nearby energization region to the point of observation. This suggests that
additional fundamentally different ion energization mechanisms are present at
high altitudes. One possibility is that the magnetic moment of the ions is
not conserved, resulting in slower outflow velocities and longer time for ion
energization
Upscaling proximal sensor N-uptake predictions in winter wheat (Triticum aestivum L.) with Sentinel-2 satellite data for use in a decision support system
Total nitrogen (N) content in aboveground biomass (N-uptake) in winter wheat (Triticum aestivum L.) as measured in a national monitoring programme was scaled up to full spatial coverage using Sentinel-2 satellite data and implemented in a decision support system (DSS) for precision agriculture. Weekly field measurements of N-uptake had been carried out using a proximal canopy reflectance sensor (handheld Yara N-Sensor) during 2017 and 2018. Sentinel-2 satellite data from two processing levels (top-of-atmosphere reflectance, L1C, and bottom-of-atmosphere reflectance, L2A) were extracted and related to the proximal sensor data (n = 251). The utility of five vegetation indices for estimation of N-uptake was compared. A linear model based on the red-edge chlorophyll index (CI) provided the best N-uptake prediction (L1C data: r(2) = 0.74, mean absolute error; MAE = 14 kg ha(-1)) when models were applied on independent sites and dates. Use of L2A data, rather than L1C, did not improve the prediction models. The CI-based prediction model was applied on all fields in an area with intensive winter wheat production. Statistics on N-uptake at the end of the stem elongation growth stage were calculated for 4169 winter wheat fields > 5 ha. Within-field variation in predicted N-uptake was > 30 kg N ha(-1) in 62% of these fields. Predicted N-uptake was compared against N-uptake maps derived from tractor-borne Yara N-Sensor measurements in 13 fields (1.7-30 ha in size). The model based on satellite data generated similar information as the tractor-borne sensing data (r(2) = 0.81; MAE = 7 kg ha(-1)), and can therefore be valuable in a DSS for variable-rate N application
Transients in Power Systems
Power system engineering largely focuses on steady state analysis. The main areas of power system engineering are power flow studies and fault studies - both steady state technologies. But the world is largely transient, and power systems are always subject to time varying and short lived signals. This technical report concerns several important topics in transient analyses of power systems. The leading chapter deals with a new analytical tool-wavelets-for power system transients. Flicker and electric are furnace transients are discussed in Chapters I1 and IV. Chapter 111 deals with transients from shunt capacitor switching. The concluding chapters deal with transformer inrush current and non simultaneous pole closures of circuit breakers. This report was prepared by the students in EE532 at Purdue University. When I first came to Purdue in 1965, Professor El-Abiad was asking for student term projects which were turned into technical reports. I have \u27borrowed\u27 this idea and for many years we have produced technical reports from the power systems courses. The students get practice in writing reports, and the reader is able to get an idea of the coverage of our courses. I think that the students have done a good job on the subject of transients in power systems
Higher-order mesoscopic fluctuations in quantum wires: Conductance and current cumulants
We study conductance cumulants and current cumulants
related to heat and electrical transport in coherent mesoscopic quantum wires
near the diffusive regime. We consider the asymptotic behavior in the limit
where the number of channels and the length of the wire in the units of the
mean free path are large but the bare conductance is fixed. A recursion
equation unifying the descriptions of the standard and Bogoliubov--de Gennes
(BdG) symmetry classes is presented. We give values and come up with a novel
scaling form for the higher-order conductance cumulants. In the BdG wires, in
the presence of time-reversal symmetry, for the cumulants higher than the
second it is found that there may be only contributions which depend
nonanalytically on the wire length. This indicates that diagrammatic or
semiclassical pictures do not adequately describe higher-order spectral
correlations. Moreover, we obtain the weak-localization corrections to
with .Comment: 7 page
- …