486 research outputs found
Effective non-linear dynamics of binary condensates and open problems
We report on a recent result concerning the effective dynamics for a mixture
of Bose-Einstein condensates, a class of systems much studied in physics and
receiving a large amount of attention in the recent literature in mathematical
physics; for such models, the effective dynamics is described by a coupled
system of non-linear Sch\"odinger equations. After reviewing and commenting our
proof in the mean field regime from a previous paper, we collect the main
details needed to obtain the rigorous derivation of the effective dynamics in
the Gross-Pitaevskii scaling limit.Comment: Corrected typos, updated reference
Reflecting back and forwards: The ebb and flow of peer-reviewed reflective practice research in sport
Researchers in sport have claimed that reflective practice is important for competent practice. Evidence supporting this claim is sparse, highly theoretical and located within a variety of domains. The aim of this study was to assimilate and analyse the last 12 years of reflective practice literature within the sport domain in order to identify new areas of inquiry, emerging trends with regard to findings or methodology, and to identify implications for future research and practice. A sample of 68 papers published between 2001 and 2012 was examined, and investigated for the research locations, data collection methods utilised, and the professions and communities involved. The paper concludes with some suggestions for future research
Gene therapy [3]
To the Editor: We remain enthusiastic about gene therapy, despite the slower-than-hoped-for rate of progress and the inefficiency of current adenoviral-mediated and liposomal-mediated CFTR gene transfer. One of the intents of our paper was to alert researchers in the field to problems with the efficiency of the adenovirus and consequently to stimulate new approaches to increase the efficiency of this vector by the use of other serotypes or new dosing strategies
Characterisation of phosphate coacervates for potential biomedical applications
In this study, amorphous (Na2O)x(CaO)0.50−x(P2O5)0.50·yH2O (where x = ∼0.15 and y = ∼3) samples were prepared by a coacervate method. Thermal analysis showed that two types of water molecules were present in the coacervate structures: one type loosely bound and the other part of the phosphate structure. Structural studies using Fourier transform infrared spectroscopy (FTIR) and X-ray total diffraction revealed the samples to have very similar structures to melt-quenched glasses of comparable composition. Furthermore, no significant structural differences were observed between samples prepared using calcium nitrate as the calcium source or those prepared from calcium chloride. A sample containing ∼1 mol% Ag2O was prepared to test the hypothesis that calcium phosphate coacervate materials could be used as delivery agents for antibacterial ions. This sample exhibited significant antibacterial activity against the bacterium Psuedomonas aeruginosa. FTIR data revealed the silver-doped sample to be structurally akin to the analogous silver-free sample
Three-body non-additive forces between spin-polarized alkali atoms
Three-body non-additive forces in systems of three spin-polarized alkali
atoms (Li, Na, K, Rb and Cs) are investigated using high-level ab initio
calculations. The non-additive forces are found to be large, especially near
the equilateral equilibrium geometries. For Li, they increase the three-atom
potential well depth by a factor of 4 and reduce the equilibrium interatomic
distance by 0.9 A. The non-additive forces originate principally from chemical
bonding arising from sp mixing effects.Comment: 4 pages, 3 figures (in 5 files
Distribution modelling and statistical phylogeography: an integrative framework for generating and testing alternative biogeographical hypotheses
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73644/1/j.1365-2699.2007.01814.x.pd
Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events
The - oscillation frequency has been measured with a sample of
23 million \B\bar B pairs collected with the BABAR detector at the PEP-II
asymmetric B Factory at SLAC. In this sample, we select events in which both B
mesons decay semileptonically and use the charge of the leptons to identify the
flavor of each B meson. A simultaneous fit to the decay time difference
distributions for opposite- and same-sign dilepton events gives ps.Comment: 7 pages, 1 figure, submitted to Physical Review Letter
A human ciliopathy reveals essential functions for NEK10 in airway mucociliary clearance
Mucociliary clearance, the physiological process by which mammalian conducting airways expel pathogens and unwanted surface materials from the respiratory tract, depends on the coordinated function of multiple specialized cell types, including basal stem cells, mucus-secreting goblet cells, motile ciliated cells, cystic fibrosis transmembrane conductance regulator (CFTR)-rich ionocytes, and immune cells1,2. Bronchiectasis, a syndrome of pathological airway dilation associated with impaired mucociliary clearance, may occur sporadically or as a consequence of Mendelian inheritance, for example in cystic fibrosis, primary ciliary dyskinesia (PCD), and select immunodeficiencies3. Previous studies have identified mutations that affect ciliary structure and nucleation in PCD4, but the regulation of mucociliary transport remains incompletely understood, and therapeutic targets for its modulation are lacking. Here we identify a bronchiectasis syndrome caused by mutations that inactivate NIMA-related kinase 10 (NEK10), a protein kinase with previously unknown in vivo functions in mammals. Genetically modified primary human airway cultures establish NEK10 as a ciliated-cell-specific kinase whose activity regulates the motile ciliary proteome to promote ciliary length and mucociliary transport but which is dispensable for normal ciliary number, radial structure, and beat frequency. Together, these data identify a novel and likely targetable signaling axis that controls motile ciliary function in humans and has potential implications for other respiratory disorders that are characterized by impaired mucociliary clearance
Crystallographic Orientation Relationship with Geometrically Necessary Dislocation Accumulation During High-Temperature Deformation in RR1000 Nickel-Based Superalloy
In the current study, it is demonstrated that soft grains along 〈100〉 fiber provided a pure shear condition for easy dislocation movement leading to a relatively low dislocation density. The hard grains along the 〈111〉 fiber, however, were not favorably oriented for slip system activation and caused high dislocation accumulation. It is concluded that the average overall dislocation density does not provide a meaningful value, as it is largely dependent on the original material crystallographic texture, the numbers of hard and soft grains in the electron backscatter diffraction (EBSD) mapped area, and the grain size factor
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