How universal is the fractional-quantum-Hall edge Luttinger liquid?

This article reports on our microscopic investigations of the edge of the fractional quantum Hall state at filling factor $\nu=1/3$. We show that the interaction dependence of the wave function is well described in an approximation that includes mixing with higher composite-fermion Landau levels in the lowest order. We then proceed to calculate the equal time edge Green function, which provides evidence that the Luttinger exponent characterizing the decay of the Green function at long distances is interaction dependent. The relevance of this result to tunneling experiments is discussed.Comment: 5 page

Reflections on a degree initiative: the UK's Birmingham Royal Ballet dancers enter the University of Birmingham

This paper provides an opportunity to share experiences and perceptions of the first 5 years of a degree programme for professional dancers. A partnership developed in the mid-1990s between the UK's Birmingham Royal Ballet and the University of Birmingham, Westhill (now School of Education), to provide a part-time, post-experience, flexible study programme for full-time Company dancers. This is the first 'company customised' higher education programme to dovetail studies around rehearsal, performance and touring schedules. Methodology is based on a narrative by the author, informed by ongoing internal and external evaluations, in-depth interviews with dancers and Company managers, documentation and secondary sources. Outcomes indicate that the programme has made a positive difference to the Company, to the dancers and to the wider education and dance/arts world

Coherent averaging of pseudorandom binary stimuli: is the dynamic cerebral autoregulatory response symmetrical?

Objective: Previous studies on cerebral autoregulation have shown the existence of hemispheric symmetry, which may be altered in stroke and traumatic brain injury. There is a paucity of data however on whether the response is symmetrical between those disturbances that cause cerebral hyperperfusion, to those that cause hypoperfusion. Our aim was to investigate whether the responses of cerebral autoregulation to haemodynamic stimuli of different directions are symmetrical. 
 Approach: Using a previously described assessment method, we employed coherent averaging of the cerebral blood flow velocity (CBFV) responses to thigh cuff inflation and deflation, as driven by pseudorandom binary sequences, whilst simultaneously altering the inspired CO2. The symmetry of the autoregulatory response was assessed with regards to two parameters, its speed and gain. Using the first harmonic method, critical closing pressure (CrCP) and resistance area product (RAP) were estimated, and the gain of the autoregulatory response was calculated by performing linear regression between the coherent averages of arterial blood pressure (ABP) and CBFV, ABP and CrCP and finally ABP and RAP. A two-way repeated measures ANOVA was used to assess for the effect of the direction of change in ABP and the method of CO2 administration. 
 Main results: Our results suggest that whilst the direction of ABP change does not have a significant effect, the effect of CO2 administration method is highly significant (p<10-4). 
 Significance: This is the first report to report to demonstrate the symmetry of the autoregulatory response to stimuli of different directions as well as the short term dynamics of RAP and CrCP under intermittent and constant hypercapnia. As haemodynamic stimulus direction does not appear to have an influence, our findings validate previous work done using different assessment methods

Order parameter model for unstable multilane traffic flow

We discuss a phenomenological approach to the description of unstable vehicle motion on multilane highways that explains in a simple way the observed sequence of the phase transitions "free flow -> synchronized motion -> jam" as well as the hysteresis in the transition "free flow synchronized motion". We introduce a new variable called order parameter that accounts for possible correlations in the vehicle motion at different lanes. So, it is principally due to the "many-body" effects in the car interaction, which enables us to regard it as an additional independent state variable of traffic flow. Basing on the latest experimental data (cond-mat/9905216) we assume that these correlations are due to a small group of "fast" drivers. Taking into account the general properties of the driver behavior we write the governing equation for the order parameter. In this context we analyze the instability of homogeneous traffic flow manifesting itself in both of the mentioned above phase transitions where, in addition, the transition "synchronized motion -> jam" also exhibits a similar hysteresis. Besides, the jam is characterized by the vehicle flows at different lanes being independent of one another. We specify a certain simplified model in order to study the general features of the car cluster self-formation under the phase transition "free flow synchronized motion". In particular, we show that the main local parameters of the developed cluster are determined by the state characteristics of vehicle motion only.Comment: REVTeX 3.1, 10 pages with 10 PostScript figure

Refractive Index of Humid Air in the Infrared: Model Fits

The theory of summation of electromagnetic line transitions is used to tabulate the Taylor expansion of the refractive index of humid air over the basic independent parameters (temperature, pressure, humidity, wavelength) in five separate infrared regions from the H to the Q band at a fixed percentage of Carbon Dioxide. These are least-squares fits to raw, highly resolved spectra for a set of temperatures from 10 to 25 C, a set of pressures from 500 to 1023 hPa, and a set of relative humidities from 5 to 60%. These choices reflect the prospective application to characterize ambient air at mountain altitudes of astronomical telescopes.Comment: Corrected exponents of c0ref, c1ref and c1p in Table

EJP18 peptide derived from the juxtamembrane domain of epidermal growth factor receptor represents a novel membrane-active cell-penetrating peptide

Membrane-active peptides have been extensively studied to probe protein–membrane interactions, to act as antimicrobial agents and cell-penetrating peptides (CPPs) for the delivery of therapeutic agents to cells. Hundreds of membrane-active sequences acting as CPPs have now been described including bioportides that serve as single entity modifiers of cell physiology at the intracellular level. Translation of promising CPPs in pre-clinical studies have, however, been disappointing as only few identified delivery systems have progressed to clinical trials. To search for novel membrane-active peptides a sequence from the EGFR juxtamembrane region was identified (named EJP18), synthesised, and examined in its L- and D-form for its ability to mediate the delivery of a small fluorophore and whole proteins to cancer cell lines. Initial studies identified the peptide as being highly membrane-active causing extensive and rapid plasma membrane reorganisation, blebbing, and toxicity. At lower, non-toxic concentrations the peptides outperformed the well-characterised CPP octaarginine in cellular delivery capacity for a fluorophore or proteins that were associated with the peptide covalently or via ionic interactions. EJP18 thus represents a novel membrane-active peptide that may be used as a naturally derived model for biophysical protein–membrane interactions or for delivery of cargo into cells for therapeutic or diagnostic applications

Maternal choline supplementation in a sheep model of first trimester binge alcohol fails to protect against brain volume reductions in peripubertal lambs

Fetal alcohol spectrum disorder (FASD) is a leading potentially preventable birth defect. Poor nutrition may contribute to adverse developmental outcomes of prenatal alcohol exposure, and supplementation of essential micronutrients such as choline has shown benefit in rodent models. The sheep model of first-trimester binge alcohol exposure was used in this study to model the dose of maternal choline supplementation used in an ongoing prospective clinical trial involving pregnancies at risk for FASD. Primary outcome measures included volumetrics of the whole brain, cerebellum, and pituitary derived from magnetic resonance imaging (MRI) in 6-month-old lambs, testing the hypothesis that alcohol-exposed lambs would have brain volume reductions that would be ameliorated by maternal choline supplementation. Pregnant sheep were randomly assigned to one of five groups – heavy binge alcohol (HBA; 2.5 g/kg/treatment ethanol), heavy binge alcohol plus choline supplementation (HBC; 2.5 g/kg/treatment ethanol and 10 mg/kg/day choline), saline control (SC), saline control plus choline supplementation (SCC; 10 mg/kg/day choline), and normal control (NC). Ewes were given intravenous alcohol (HBA, HBC; mean peak BACs of ~280 mg/dL) or saline (SC, SCC) on three consecutive days per week from gestation day (GD) 4–41; choline was administered on GD 4–148. MRI scans of lamb brains were performed postnatally on day 182. Lambs from both alcohol groups (with or without choline) showed significant reductions in total brain volume; cerebellar and pituitary volumes were not significantly affected. This is the first report of MRI-derived volumetric brain reductions in a sheep model of FASD following binge-like alcohol exposure during the first trimester. These results also indicate that maternal choline supplementation comparable to doses in human studies fails to prevent brain volume reductions typically induced by first-trimester binge alcohol exposure. Future analyses will assess behavioral outcomes along with regional brain and neurohistological measures

Enhancement and suppression effects resulting from information structuring in sentences

Information structuring through the use of cleft sentences increases the processing efficiency of references to elements within the scope of focus. Furthermore, there is evidence that putting certain types of emphasis on individual words not only enhances their subsequent processing, but also protects these words from becoming suppressed in the wake of subsequent information, suggesting mechanisms of enhancement and suppression. In Experiment 1, we showed that clefted constructions facilitate the integration of subsequent sentences that make reference to elements within the scope of focus, and that they decrease the efficiency with reference to elements outside of the scope of focus. In Experiment 2, using an auditory text-change-detection paradigm, we showed that focus has similar effects on the strength of memory representations. These results add to the evidence for enhancement and suppression as mechanisms of sentence processing and clarify that the effects occur within sentences having a marked focus structure