Simulated three-component granular segregation in a rotating drum

Discrete particle simulations are used to model segregation in granular mixtures of three different particle species in a horizontal rotating drum. Axial band formation is observed, with medium-size particles tending to be located between alternating bands of big and small particles. Partial radial segregation also appears; it precedes the axial segregation and is characterized by an inner core region richer in small particles. Axial bands are seen to merge during the long simulation runs, leading to a coarsening of the band pattern; the relocation of particles involved in one such merging event is examined. Overall, the behavior is similar to experiment and represents a generalization of what occurs in the simpler two-component mixture.Comment: 7 pages, 11 figures (low resolution color figures only; originals at author's website http://www.ph.biu.ac.il/~rapaport/research/granular.html) [revised version contains extra figures

Correlations in a two-dimensional Bose gas with long range interactions

We study the correlations of two-dimensional dipolar excitons in coupled quantum wells with a dipole -- dipole repulsive interaction. We show that at low concentrations, the Bose degeneracy of the excitons is accompanied by strong multi-particle correlations and the system behaves as a Bose liquid. At high concentration the particles interaction suppresses quantum coherence and the system behaves similar to a classical liquid down to a temperature lower than typical for a Bose gas. We evaluate the interaction energy per particle and the resulting blue shift of the exciton luminescence that is a direct tool to measure the correlations. This theory can apply to other systems of bosons with extended interaction.Comment: 11 pages including 2 figure

Microscale swimming: The molecular dynamics approach

The self-propelled motion of microscopic bodies immersed in a fluid medium is studied using molecular dynamics simulation. The advantage of the atomistic approach is that the detailed level of description allows complete freedom in specifying the swimmer design and its coupling with the surrounding fluid. A series of two-dimensional swimming bodies employing a variety of propulsion mechanisms -- motivated by biological and microrobotic designs -- is investigated, including the use of moving limbs, changing body shapes and fluid jets. The swimming efficiency and the nature of the induced, time-dependent flow fields are found to differ widely among body designs and propulsion mechanisms.Comment: 5 pages, 3 figures (minor changes to text

Molecular dynamics simulations of the evaporation of particle-laden droplets

We use molecular dynamics simulations to study the evaporation of particle-laden droplets on a heated surface. The droplets are composed of a Lennard-Jones fluid containing rigid particles which are spherical sections of an atomic lattice, and heating is controlled through the temperature of an atomistic substrate. We observe that sufficiently large (but still nano-sized) particle-laden drops exhibit contact line pinning, measure the outward fluid flow field which advects particle to the drop rim, and find that the structure of the resulting aggregate varies with inter-particle interactions. In addition, the profile of the evaporative fluid flux is measured with and without particles present, and is also found to be in qualitative agreement with earlier theory. The compatibility of simple nanoscale calculations and micron-scale experiments indicates that molecular simulation may be used to predict aggregate structure in evaporative growth processes

Self-similar measures associated to a homogeneous system of three maps

We study the dimension of self-similar measures associated to a homogeneous iterated function system of three contracting similarities on $\bf R$ and other more general IFS's. We extend some of the theory recently developed for Bernoulli convolutions to this setting. In the setting of three maps a new phenomenon occurs, which has been highlighted by recent examples of Baker, and B\'ar\'any, K\"aenm\"aki. To overcome the difficulties stemming form these, we develop novel techniques, including an extension of Hochman's entropy increase method to a function field setup.Comment: 82 page

Hard Spheres: Crystallization and Glass Formation

Motivated by old experiments on colloidal suspensions, we report molecular dynamics simulations of assemblies of hard spheres, addressing crystallization and glass formation. The simulations cover wide ranges of polydispersity s (standard deviation of the particle size distribution divided by its mean) and particle concentration. No crystallization is observed for s > 0.07. For 0.02 < s < 0.07, we find that increasing the polydispersity at a given concentration slows down crystal nucleation. The main effect here is that polydispersity reduces the supersaturation since it tends to stabilise the fluid but to destabilise the crystal. At a given polydispersity (< 0.07) we find three regimes of nucleation: standard nucleation and growth at concentrations in and slightly above the coexistence region; "spinodal nucleation", where the free energy barrier to nucleation appears to be negligible, at intermediate concentrations; and, at the highest concentrations, a new mechanism, still to be fully understood, which only requires small re-arrangement of the particle positions. The cross-over between the second and third regimes occurs at a concentration, around 58% by volume, where the colloid experiments show a marked change in the nature of the crystals formed and the particle dynamics indicate an "ideal" glass transition

DAMAGES - INJUNCTION BOND - ATTORNEY\u27S FEES AS DAMAGES

Frequently, when a litigant seeks to establish rights with respect to particular property, it is possible for the opposing party so to act with respect to the property involved, while litigation is pending, as to deprive the plaintiff of the substantial benefit of his remedy should he prevail. Consequently, on prima facie showing of right, courts of equity will grant a temporary injunction to freeze the situation until the rights of the parties are finally determined. Since the temporary injunction is issued without a final determination of the rights of the parties, the enjoined party is deprived of dominion over the subject matter before it is finally decided that dominion is not rightfully his. Therefore, should he ultimately prevail in the action, he is deprived of whatever benefits he might have gained through the exercise of his rights in connection with the subject matter during the interim between the issuance of the temporary injunction and the final hearing. Courts of equity, recognizing this source of hardship, have required as a condition precedent to the issuance of a temporary injunction that the plaintiff execute a bond conditioned on payment of all damages the defendant might sustain by reason of the temporary injunction, should it be finally determined that such injunction ought not to have been issued. In an action on the injunction bond, it is obvious that such injuries as are occasioned by defendant\u27s being deprived of dominion over the property are compensable. However, a more difficult problem is put to the court when it must decide whether attorney fees incurred for procuring dissolution of the temporary injunction are similarly within the condition of the bond. It is with this latter problem that this comment is concerned

Long-term implementation of the Managing Agitation and Raising QUality of lifE intervention in care homes: A qualitative study

OBJECTIVES: The dementia care home workforce receive little specific training. There are successful interventions, improving care outcomes, but it is unclear whether or how to sustain these effects. The Managing Agitation and Raising Quality of Life (MARQUE) intervention aimed to train care home staffto reduce resident's agitation and improve their quality of life. It was designed for sustainability, with implementation plans agreed with managers. MARQUE improves quality of life. In this separate study, we aimed to examine implementation around two years later. METHODS: and design: We explored practice change since the intervention and considered current implementation of home specific action plans, enablers or barriers, and perceived benefits or harms of implementation using semi-structured interviews with staff working in the trial homes who received the MARQUE intervention. RESULTS: 6/10 intervention homes participated. We interviewed 25 staff, 20-30 months after the MARQUE study. In all homes, staff reported that at least one MARQUE component was sustained. Three themes emerged about sustained practice change: (i) communication, (ii) respect and understanding of roles, and (iii) ability to try new things. Notable changes included improved team working and feelings of competence, positive attitude to residents rather than blame for agitation and avoidance, and more pleasant activities. Leadership support was important. CONCLUSIONS: It is possible to sustain some change over years in care homes. This study indicates factors which help or impede. These factors individually and together could lead to long-term improved quality of life of residents in homes where it is implemented and sustained. This article is protected by copyright. All rights reserved