Shear Flows of Rapidly Flowing Granular Materials

Shear flows of granular materials are studied in an open channel. The wall shear is calculated from an open channel momentum equation which includes the density variations in the flow. An experimental technique was developed that allowed the measurement of the average density of the flow at different longitudinal locations in the channel. Two sizes of glass beads are examined and results show the variations in the wall shear as a function of various dimensionless parameters

Flight tests of a direct lift control system during approach and landing

Flight tests of modified aileron direct lift control system during approach and landing of F8-C aircraf

Synthesis of perfluorinated polyethers

A series of highly fluorinated acetylenes was prepared and their cyclization reactions were studied. A series of perfluoropolytriazines with -CF2I pendent groups were prepared. These materials can be cured thermally or photochemically to an elastomeric gum. Perfluoropolytriazines with -CN pendent groups were prepared. These materials can be crosslinked by reaction with terephthalonitrile oxide

A Flight Evaluation of a VTOL Jet Transport Under Visual and Simulated Instrument Conditions

Transition, approach, and vertical landing tests for VTOL transport in terminal are

A pilot study of the S-MAP (Solutions for Medications Adherence Problems) intervention for older adults prescribed polypharmacy in primary care: Study protocol

Background: Adhering to multiple medications as prescribed is challenging for older patients (aged ≥ 65 years) and a difficult behaviour to improve. Previous interventions designed to address this have been largely complex in nature but have shown limited effectiveness and have rarely used theory in their design. It has been recognised that theory ('a systematic way of understanding events or situations') can guide intervention development and help researchers better understand how complex adherence interventions work. This pilot study aims to test a novel community pharmacy-based intervention that has been systematically developed using the Theoretical Domains Framework (12-domain version) of behaviour change. Methods: As part of a non-randomised pilot study, pharmacists in 12 community pharmacies across Northern Ireland (n = 6) and London, England (n = 6), will be trained to deliver the intervention to older patients who are prescribed ≥ 4 regular medicines and are non-adherent (self-reported). Ten patients will be recruited per pharmacy (n = 120) and offered up to four tailored one-to-one sessions, in the pharmacy or via telephone depending on their adherence, over a 3-4-month period. Guided by an electronic application (app) on iPads, the intervention content will be tailored to each patient's underlying reasons for non-adherence and mapped to the most appropriate solutions using established behaviour change techniques. This study will assess the feasibility of collecting data on the primary outcome of medication adherence (self-report and dispensing data) and secondary outcomes (health-related quality of life and unplanned hospitalisations). An embedded process evaluation will assess training fidelity for pharmacy staff, intervention fidelity, acceptability to patients and pharmacists and the intervention's mechanism of action. Process evaluation data will include audio-recordings of training workshops, intervention sessions, feedback interviews and patient surveys. Analysis will be largely descriptive. Discussion: Using pre-defined progression criteria, the findings from this pilot study will guide the decision whether to proceed to a cluster randomised controlled trial to test the effectiveness of the S-MAP intervention in comparison to usual care in community pharmacies. The study will also explore how the intervention components may work to bring about change in older patients' adherence behaviour and guide further refinement of the intervention and study procedures. Trial registration: This study is registered at ISRCTN: https://doi.org/10.1186/ISRCTN7383153

Dissipation due to tunneling two-level systems in gold nanomechanical resonators

We present measurements of the dissipation and frequency shift in nanomechanical gold resonators at temperatures down to 10 mK. The resonators were fabricated as doubly-clamped beams above a GaAs substrate and actuated magnetomotively. Measurements on beams with frequencies 7.95 MHz and 3.87 MHz revealed that from 30 mK to 500 mK the dissipation increases with temperature as $T^{0.5}$, with saturation occurring at higher temperatures. The relative frequency shift of the resonators increases logarithmically with temperature up to at least 400 mK. Similarities with the behavior of bulk amorphous solids suggest that the dissipation in our resonators is dominated by two-level systems

Nonlinear modal coupling in a high-stress doubly-clamped nanomechanical resonator

We present results from a study of the nonlinear intermodal coupling between different flexural vibrational modes of a single high-stress, doubly-clamped silicon nitride nanomechanical beam. The measurements were carried out at 100 mK and the beam was actuated using the magnetomotive technique. We observed the nonlinear behavior of the modes individually and also measured the coupling between them by driving the beam at multiple frequencies. We demonstrate that the different modes of the resonator are coupled to each other by the displacement induced tension in the beam, which also leads to the well known Duffing nonlinearity in doubly-clamped beams.Comment: 15 pages, 7 figure

Galaxy pairs in the Sloan Digital Sky Survey - IX: Merger-induced AGN activity as traced by the Wide-field Infrared Survey Explorer

Interactions between galaxies are predicted to cause gas inflows that can potentially trigger nuclear activity. Since the inflowing material can obscure the central regions of interacting galaxies, a potential limitation of previous optical studies is that obscured Active Galactic Nuclei (AGNs) can be missed at various stages along the merger sequence. We present the first large mid-infrared study of AGNs in mergers and galaxy pairs, in order to quantify the incidence of obscured AGNs triggered by interactions. The sample consists of galaxy pairs and post-mergers drawn from the Sloan Digital Sky Survey that are matched to detections by the Wide Field Infrared Sky Explorer (WISE). We find that the fraction of AGN in the pairs, relative to a mass-, redshift- and environment-matched control sample, increases as a function of decreasing projected separation. This enhancement is most dramatic in the post-merger sample, where we find a factor of 10-20 excess in the AGN fraction compared with the control. Although this trend is in qualitative agreement with results based on optical AGN selection, the mid-infrared selected AGN excess increases much more dramatically in the post-mergers than is seen for optical AGN. Our results suggest that energetically dominant optically obscured AGNs become more prevalent in the most advanced mergers, consistent with theoretical predictions.Comment: 8 pages, 7 figures accepted to MNRAS (with minor revisions

Breakdown by a magnetic field of the superconducting fluctuations in the normal state: A simple phenomenological explanation

We first summarize our recent observations, through magnetization measurements in different low-Tc superconductors, of a rather sharp disappearance of the superconducting fluctuations in the normal state when the magnetic field approaches Hc2(0), the upper critical field extrapolated to T=0K. We propose that a crude phenomenological description of the observed effects may be obtained if the quantum limits associated with the uncertainty principle are introduced in the Gaussian-Ginzburg-Landau description of the fluctuation-induced magnetization.Comment: LaTeX, 8 pages, including 2 eps figures. Proceedings of SNS'04, Sitges, Spai

A Hubble Space Telescope Snapshot Survey of Dynamically Close Galaxy Pairs in the CNOC2 Redshift Survey

We compare the structural properties of two classes of galaxies at intermediate redshift: those in dynamically close galaxy pairs, and those which are isolated. Both samples are selected from the CNOC2 Redshift Survey, and have redshifts in the range 0.1 < z <0.6. Hubble Space Telescope WFPC2 images were acquired as part of a snapshot survey, and were used to measure bulge fraction and asymmetry for these galaxies. We find that paired and isolated galaxies have identical distributions of bulge fractions. Conversely, we find that paired galaxies are much more likely to be asymmetric (R_T+R_A >= 0.13) than isolated galaxies. Assuming that half of these pairs are unlikely to be close enough to merge, we estimate that 40% +/- 11% of merging galaxies are asymmetric, compared with 9% +/- 3% of isolated galaxies. The difference is even more striking for strongly asymmetric (R_T+R_A >= 0.16) galaxies: 25% +/- 8% for merging galaxies versus 1% +/- 1% for isolated galaxies. We find that strongly asymmetric paired galaxies are very blue, with rest-frame B-R colors close to 0.80, compared with a mean (B-R)_0 of 1.24 for all paired galaxies. In addition, asymmetric galaxies in pairs have strong [OII]3727 emission lines. We conclude that close to half of the galaxy pairs in our sample are in the process of merging, and that most of these mergers are accompanied by triggered star formation.Comment: Accepted for publication in the Astronomical Journal. 40 pages, including 15 figures. For full resolution version, please see http://www.trentu.ca/physics/dpatton/hstpairs