Determining White Noise Forcing From Eulerian Observations in the Navier Stokes Equation

The Bayesian approach to inverse problems is of paramount importance in quantifying uncertainty about the input to and the state of a system of interest given noisy observations. Herein we consider the forward problem of the forced 2D Navier Stokes equation. The inverse problem is inference of the forcing, and possibly the initial condition, given noisy observations of the velocity field. We place a prior on the forcing which is in the form of a spatially correlated temporally white Gaussian process, and formulate the inverse problem for the posterior distribution. Given appropriate spatial regularity conditions, we show that the solution is a continuous function of the forcing. Hence, for appropriately chosen spatial regularity in the prior, the posterior distribution on the forcing is absolutely continuous with respect to the prior and is hence well-defined. Furthermore, the posterior distribution is a continuous function of the data. We complement this theoretical result with numerical simulation of the posterior distribution

Practical Pedagogy for Embedding Drone Technology into a Business and Computing Curriculum

This paper outlines the design of an undergraduate module in "Applied Drone Technology‟ to enhance student engagement and learning of a new technology within a business school curriculum. It focuses on the development strategy and issues the team encountered when trying to create something outside the usual core computing and business curriculum. Although there are barriers and issues to integrating drones into a curriculum, it can be accomplished with proper planning and a strategic vision. The result was a module that can be used by students in a business school, but with the capability of being used by students in other academic units

Corticosteroid implants for chronic non-infectious uveitis.

BACKGROUND: Uveitis is a term used to describe a heterogeneous group of intraocular inflammatory diseases of the anterior, intermediate, and posterior uveal tract (iris, ciliary body, choroid). Uveitis is the fifth most common cause of vision loss in high-income countries, accounting for 5% to 20% of legal blindness, with the highest incidence of disease in the working-age population.Corticosteroids are the mainstay of acute treatment for all anatomical subtypes of non-infectious uveitis and can be administered orally, topically with drops or ointments, by periocular (around the eye) or intravitreal (inside the eye) injection, or by surgical implantation. OBJECTIVES: To determine the efficacy and safety of steroid implants in people with chronic non-infectious posterior uveitis, intermediate uveitis, and panuveitis. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (Issue 10, 2015), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2015), EMBASE (January 1980 to November 2015), PubMed (1948 to November 2015), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to November 2015), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 15 April 2013), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic search for studies. We last searched the electronic databases on 6 November 2015.We also searched reference lists of included study reports, citation databases, and abstracts and clinical study presentations from professional meetings. SELECTION CRITERIA: We included randomized controlled trials comparing either fluocinolone acetonide (FA) or dexamethasone intravitreal implants with standard-of-care therapy with at least six months of follow-up after treatment. We included studies that enrolled participants of all ages who had chronic non-infectious posterior uveitis, intermediate uveitis, or panuveitis with vision that was better than hand-motion. DATA COLLECTION AND ANALYSIS: Two review authors independently reviewed studies for inclusion. Two review authors independently extracted data and assessed the risk of bias for each study. MAIN RESULTS: We included data from two studies (619 eyes of 401 participants) that compared FA implants with standard-of-care therapy. Both studies used similar standard-of-care therapy that included administration of prednisolone and, if needed, immunosuppressive agents. The studies included participants from Australia, France, Germany, Israel, Italy, Portugal, Saudi Arabia, Spain, Switzerland, Turkey, the United Kingdom, and the United States. We assessed both studies at high risk of performance and detection bias.Only one study reported our primary outcome, recurrence of uveitis at any point during the study through 24 months. The evidence, judged as moderate-quality, showed that a FA implant probably prevents recurrence of uveitis compared with standard-of-care therapy (risk ratio (RR) 0.29, 95% confidence interval (CI) 0.14 to 0.59; 132 eyes). Both studies reported safety outcomes, and moderate-quality evidence showed increased risks of needing cataract surgery (RR 2.98, 95% CI 2.33 to 3.79; 371 eyes) and surgery to lower intraocular pressure (RR 7.48, 95% CI 3.94 to 14.19; 599 eyes) in the implant group compared with standard-of-care therapy through two years of follow-up. No studies compared dexamethasone implants with standard-of-care therapy. AUTHORS\u27 CONCLUSIONS: After considering both benefits and harms reported from two studies in which corticosteroids implants were compared with standard-of-care therapy, we are unable to conclude that the implants are superior to traditional systemic therapy for the treatment of non-infectious uveitis. These studies exhibited heterogeneity in design and outcomes that measured efficacy. Pooled findings regarding safety outcomes suggest increased risks of post-implant surgery for cataract and high intraocular pressure compared with standard-of-care therapy

The Composition and Properties of Bovine, Caprine and Ovine Milk Proteins

Analytical methods of ion-exchange and gel permeation chromatography were developed to determine the composition of the caseinate complex and the whey protein fraction in bovine, caprine and ovine milk. These methods were subsequently used to study natural variation in the composition of the milk proteins, casein micellar structure and stability, and changes in the proteins during milk processing. Initially traditional anion-exchange chromatography on DEAE-cellulose was used to examine the composition of bovine casein, but a more rapid method of anion-exchange FPLC (fast protein liquid chromatography) was introduced in which the main fractions, namely alphas1-, beta-, alphas2-, kappa- and gamma-caseins, were separated under dissociating conditions at pH 7.0. A complementary method of cation-exchange FPLC, in which the caseins were separated under dissociating conditions at pH 5.0, was also developed to determine the compositions of bovine, caprine and ovine caseins. Both methods could also be used on a preparative scale. In detailed studies of natural variation in the composition of bovine casein, it was found that in creamery milk in South-West Scotland there was a pronounced seasonal variation in the concentrations of the total and individual proteins but that the relative amounts of the proteins did not vary markedly. The composition of whole casein from individual cows, however, was affected by genetic polymorphism of kappa-casein. The relative amount of kappa-casein in whole casein varied with phenotype in the order kappa-casein BB > AB > AA; on average there was about 25 % more kappa-casein in whole casein containing the BB phenotype than in that containing the AA phenotype. The presence of beta-casein A1, A2 or B genetic variants had no significant effect on casein composition. Compared with bovine casein, caprine casein contained much less alphas1-casein, a similar amount of alphas2, and much more beta- and kappa-caseins. Caprine casein was also much more variable in composition, due to the occurrence of an unusual, quantitative genetic polymorphism of alphas1-casein. Polymorphism of caprine kappa-casein was also studied and it was found that although the amount of kappa-casein varied between 9 and 20% of the total casein, the variants were produced in approximately equal amounts in the heterozygotes. There was considerable variation in the composition of individual samples of ovine casein, mainly due to proteolysis of beta-casein. Compared with bovine casein, ovine casein contained much less alphas-casein, considerably more beta-casein and approximately the same amount of kappa-casein. In a study of the composition of bulk milk from a commercial dairy flock, it was found that there were considerable seasonal changes in the concentrations of total and individual proteins, but the relative amounts of the proteins remained fairly constant. The composition of the whey protein fraction of all three species was determined by gel permeation FPLC, and four main fractions were separated at pH 7.0. Compared with bovine whey protein, caprine whey protein contained less beta-lactoglobulin and more alpha-lactalbumin, whereas ovine whey protein contained slightly more beta-lactoglobulin and less alpha-lactalbumin. The methods of casein analysis were combined with ultracentrifugation to examine in detail the composition and stability of casein micelles, and in particular the effect of temperature and pH on the dissociation of the caseins and calcium phosphate from the micelles. On cooling milk there was a marked increase in the level of serum casein, which was due almost entirely to kappa-casein dissociating from the micelles. The change in distribution of micellar and serum casein was completely reversed on re-equilibration at 2

Reproductive Failure in UK Harbour Porpoises Phocoena phocoena : Legacy of Pollutant Exposure?

This research was supported by a Marie Curie International Outgoing Fellowship within the Seventh European Community Framework Programme (Project Cetacean-stressors, PIOF-GA-2010-276145 to PDJ and SM). Additional funding was provided through the Agreement on the Conservation of Small Cetaceans of the Baltic, North East Atlantic, Irish and North Seas (ASCOBANS) (Grants SSFA/2008 and SSFA / ASCOBANS / 2010 / 5 to SM). Analysis of Scottish reproductive and teeth samples was funded by the EC-funded BIOCET project (BIOaccumulation of persistent organic pollutants in small CETaceans in European waters: transport pathways and impact on reproduction, grant EVK3-2000-00027 to GJP), and Marine Scotland (GJP). Samples examined in this research were collected under the collaborative Cetacean Strandings Investigation Programme (http://ukstrandings.org/), which is funded by the Department for Environment, Food and Rural Affairs (Defra) and the UK’s Devolved Administrations in Scotland and Wales (http://sciencesearch.defra.gov.uk/Defaul​t.aspx?Menu=Menu&Module=More&Location=No​ne&Completed=0&ProjectID=15331) (grants to PDJ, RD). UK Defra also funded the chemical analysis under a service-level agreement with the Centre for Environment, Fisheries and Aquaculture Science (grants to RJL, JB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

A Millisecond Interferometric Search for Fast Radio Bursts with the Very Large Array

We report on the first millisecond timescale radio interferometric search for the new class of transient known as fast radio bursts (FRBs). We used the Very Large Array (VLA) for a 166-hour, millisecond imaging campaign to detect and precisely localize an FRB. We observed at 1.4 GHz and produced visibilities with 5 ms time resolution over 256 MHz of bandwidth. Dedispersed images were searched for transients with dispersion measures from 0 to 3000 pc/cm3. No transients were detected in observations of high Galactic latitude fields taken from September 2013 though October 2014. Observations of a known pulsar show that images typically had a thermal-noise limited sensitivity of 120 mJy/beam (8 sigma; Stokes I) in 5 ms and could detect and localize transients over a wide field of view. Our nondetection limits the FRB rate to less than 7e4/sky/day (95% confidence) above a fluence limit of 1.2 Jy-ms. Assuming a Euclidean flux distribution, the VLA rate limit is inconsistent with the published rate of Thornton et al. We recalculate previously published rates with a homogeneous consideration of the effects of primary beam attenuation, dispersion, pulse width, and sky brightness. This revises the FRB rate downward and shows that the VLA observations had a roughly 60% chance of detecting a typical FRB and that a 95% confidence constraint would require roughly 500 hours of similar VLA observing. Our survey also limits the repetition rate of an FRB to 2 times less than any known repeating millisecond radio transient.Comment: Submitted to ApJ. 13 pages, 9 figure

High speed quantum gates with cavity quantum electrodynamics

Cavity quantum electrodynamic schemes for quantum gates are amongst the earliest quantum computing proposals. Despite continued progress, and the dramatic recent demonstration of photon blockade, there are still issues with optimal coupling and gate operation involving high-quality cavities. Here we show dynamic control techniques that allow scalable cavity-QED based quantum gates, that use the full bandwidth of the cavities. When applied to quantum gates, these techniques allow an order of magnitude increase in operating speed, and two orders of magnitude reduction in cavity Q, over passive cavity-QED architectures. Our methods exploit Stark shift based Q-switching, and are ideally suited to solid-state integrated optical approaches to quantum computing.Comment: 4 pages, 3 figures, minor revision

Conservation of Side-Chain Dynamics Within a Protein Family

The question of protein dynamics and its relevance to function is currently a topic of great interest. Proteins are particularly dynamic at the side-chain level on the timescale of picoseconds to nanoseconds. Here, we present a comparison of NMR-monitored side-chain motion between three PDZ domains of ∼30% sequence identity and show that the side-chain dynamics display non-trivial conservation. Methyl 2H relaxation was carried out to determine side-chain order parameters (S2), which were found to be more similar than naively expected from sequence, local packing, or a combination of the two. Thus, the dynamics of a rather distant homolog appears to be an excellent predictor of a protein's side-chain dynamics, and, on average, better than current structure-based methods. Fast side-chain dynamics therefore display a high level of organization associated with global fold. Beyond simple conservation, the analysis herein suggests that the pattern of side-chain flexibility has significant contributions from non-local elements of the PDZ fold, such as correlated motions, and that the conserved dynamics may directly support function

The Evolutionary Status of SS433

We consider possible evolutionary models for SS 433. We assume that common-envelope evolution is avoided if radiation pressure is able to expel most of a super-Eddington accretion flow from a region smaller than the accretor's Roche lobe. This condition is satisfied, at least initially, for largely radiative donors with masses in the range 4-12 solar masses. For donors more massive than about 5 solar masses, moderate mass ratios q = M_2/M_1 > 1 are indicated, thus tending to favor black-hole accretors. For lower mass donors, evolutionary considerations do not distinguish between a neutron star or black hole accretor. In all cases the mass transfer (and mass loss) rates are much larger than the likely mass-loss rate in the precessing jets. Almost all of the transferred mass is expelled at radii considerably larger than the jet acceleration region, producing the "stationary" H-alpha line, the infrared luminosity, and accounting for the low X-ray luminosity.Comment: 13 pages, Astrophysical Journal Letters, accepte