661 research outputs found
Polaron to molecule transition in a strongly imbalanced Fermi gas
A single down spin Fermion with an attractive, zero range interaction with a
Fermi sea of up-spin Fermions forms a polaronic quasiparticle. The associated
quasiparticle weight vanishes beyond a critical strength of the attractive
interaction, where a many-body bound state is formed. From a variational
wavefunction in the molecular limit, we determine the critical value for the
polaron to molecule transition. The value agrees well with the diagrammatic
Monte Carlo results of Prokof'ev and Svistunov and is consistent with recent
rf-spectroscopy measurements of the quasiparticle weight by Schirotzek et. al.
In addition, we calculate the contact coefficient of the strongly imbalanced
gas, using the adiabatic theorem of Tan and discuss the implications of the
polaron to molecule transition for the phase diagram of the attractive Fermi
gas at finite imbalance.Comment: 10 pages, 4 figures, RevTex4, minor changes, references adde
On a modular property of N=2 superconformal theories in four dimensions
In this note we discuss several properties of the Schur index of N=2
superconformal theories in four dimensions. In particular, we study modular
properties of this index under SL(2,Z) transformations of its parameters.Comment: 23 page, 2 figure
Electrochemistry at nanoscale electrodes : individual single-walled carbon nanotubes (SWNTs) and SWNT-templated metal nanowires
Individual nanowires (NWs) and native single-walled carbon nanotubes (SWNTs) can be readily used as well-defined nanoscale electrodes (NSEs) for voltammetric analysis. Here, the simple photolithography-free fabrication of submillimeter long Au, Pt, and Pd NWs, with sub-100 nm heights, by templated electrodeposition onto ultralong flow-aligned SWNTs is demonstrated. Both individual Au NWs and SWNTs are employed as NSEs for electron-transfer (ET) kinetic quantification, using cyclic voltammetry (CV), in conjunction with a microcapillary-based electrochemical method. A small capillary with internal diameter in the range 30â70 ÎŒm, filled with solution containing a redox-active mediator (FcTMA+ ((trimethylammonium)methylferrocene), Fe(CN)64â, or hydrazine) is positioned above the NSE, so that the solution meniscus completes an electrochemical cell. A 3D finite-element model, faithfully reproducing the experimental geometry, is used to both analyze the experimental CVs and derive the rate of heterogeneous ET, using ButlerâVolmer kinetics. For a 70 nm height Au NW, intrinsic rate constants, k0, up to ca. 1 cm sâ1 can be resolved. Using the same experimental configuration the electrochemistry of individual SWNTs can also be accessed. For FcTMA+/2+ electrolysis the simulated ET kinetic parameters yield very fast ET kinetics (k0 > 2 ± 1 cm sâ1). Some deviation between the experimental voltammetry and the idealized model is noted, suggesting that double-layer effects may influence ET at the nanoscale
Effectiveness and Overall Safety of NutropinAq (R) for Growth Hormone Deficiency and Other Paediatric Growth Hormone Disorders: Completion of the International Cooperative Growth Study, NutropinAq (R) European Registry (iNCGS)
Objective: The International Cooperative Growth Study, NutropinAqÂź European Registry (iNCGS) (NCT00455728) monitored long-term safety and effectiveness of recombinant human growth hormone (rhGH; NutropinAqÂź [somatropin]) in paediatric growth disorders.
Methods: Open-label, non-interventional, post-marketing surveillance study recruiting children with growth disorders. Endpoints included gain in height standard deviation score (SDS), adult height, and occurrence of adverse events (AEs).
Results: 2792 patients were enrolled. 2082 patients (74.6%) had growth hormone deficiency (GHD), which was isolated idiopathic in 1825 patients (87.7%). Non-GHD diagnoses included Turner syndrome (TS) (n=199), chronic renal insufficiency (CRI) (n=10), other non-GHD (n=498), and missing data for three participants. Improvements from baseline height SDS occurred at all time points to Month 132, and in all subgroups by disease aetiology. At Month 12, mean (95% CI) change in height SDS by aetiology was: idiopathic GHD 0.63 (0.61;0.66), organic GHD 0.71 (0.62;0.80), TS 0.59 (0.53; 0.65), CRI 0.54 (-0.49;1.56), and other non-GHD 0.64 (0.59;0.69). Mean height ( ± SD) at the last visit among the 235 patients with adult or near-adult height recorded was 154.0 cm ( ± 8.0) for girls and 166.7 cm ( ± 8.0) for boys. The most frequent biological and clinical non-serious drug-related AEs were increased insulin-like growth factor concentrations (314 events) and injection site haematoma (99 events). Serious AEs related to rhGH according to investigators were reported (n=30); the most frequent were scoliosis (4 events), epiphysiolysis (3 events), and strabismus (2 events).
Conclusions: There was an improvement in mean height SDS in all aetiology subgroups after rhGH treatment. No new safety concerns were identified
An edge-queued datagram service for all datacenter traffic
Modern datacenters support a wide range of protocols and in-network switch enhancements aimed at improving performance. Unfortunately, the resulting protocols often do not coexist gracefully because they inevitably interact via queuing in the network. In this paper we describe EQDS, a new datagram service for datacenters that moves almost all of the queuing out of the core network and into the sending host. This enables it to support multiple (conflicting) higher layer protocols, while only sending packets into the network according to any receiver-driven credit scheme. EQDS can transparently speed up legacy TCP and RDMA stacks, and enables transport protocol evolution, while benefiting from future switch enhancements without needing to modify higher layer stacks. We show through simulation and multiple implementations that EQDS can reduce FCT of legacy TCP by 2x, improve the NVMeOF-RDMA throughput by 30%, and safely run TCP alongside RDMA on the same network
A REAL-TIME MONITORING APPLICATION OF ENVIRONMENTAL CONDITIONS IN PROTECTED AREAS
With the development of technology, the greenhouse sector is constantly expanding, which is advantageous in terms of material economy, cost reduction, improved lighting efficiency and cultivation, but at the same time requires the implementation of a large number of sensor nodes to ensure coverage of environmental monitoring. The paper presents a real-time monitoring application of environmental conditions in a greenhouse, which includes sensors for monitoring temperature, relative humidity; CO2 concentration; soil temperature (at 3 depths: ground level, 10, 20 cm)
Three form potential in (special) minimal supergravity superspace and supermembrane supercurrent
This contribution begins the study of the complete superfield Lagrangian
description of the interacting system of D=4 N=1 supergravity (SUGRA) and
supermembrane. Firstly, we review a 'three form supergravity' by Ovrut and
Waldram, which we prefer to call 'special minimal supergravity'. This off-shell
formulation of simple SUGRA is appropriate for our purposes as the
supermembrane action contains the so-called Wess-Zumino term given by the
integral over a three form potential in superspace, C3. We describe this
formulation in the frame of Wess--Zumino superfield approach, showing how the
basic variations of minimal SUGRA are restricted by the conditions of the
existence of a three-form potential C3 in its superspace. In this language the
effect of dynamical generation of cosmological constant, known to be
characteristic for this formulation of SUGRA, appears in its superfield form,
first described by Ogievetsky and Sokatchev in their formulation of SUGRA as a
theory of axial vector superfield. Secondly, we vary the supermembrane action
with respect to the special minimal SUGRA superfields (basic variations) and
obtain the supercurrent superfields as well as the supergravity superfield
equations with the supermembrane contributions.Comment: 18 pages, no figures. V2: Important references added. The abstract
and presentation have been changed to reflect the overloop with that.
Submitted to the QTS7 Proceedings. J. Phys. style use
- âŠ