Atomic selfordering in a ring cavity with counterpropagating pump

The collective dynamics of mobile scatterers and light in optical resonators generates complex behaviour. For strong transverse illumination a phase transition from homogeneous to crystalline particle order appears. In contrast, a gas inside a single-side pumped ring cavity exhibits an instability towards bunching and collective acceleration called collective atomic recoil lasing (CARL). We demonstrate that by driving two orthogonally polarized counter propagating modes of a ring resonator one realises both cases within one system. The corresponding phase diagram depending on the two pump intensities exhibits regions in which either a generalized form of self-ordering towards a travelling density wave with constant centre of mass velocity or a CARL instability is formed. Controlling the cavity driving then allows to accelerate or slow down and trap a sufficiently dense beam of linearly polarizable particles.Comment: 5 page

Impact of Robotic Dispensing Machines in German Pharmacies on Business Performance Indicators

Aims and objectives: To assess the impact of robotic dispensing machines in community pharmacies on staff efficiency and sales of over-the-counter drugs. Setting: The study was done on 253 community pharmacies in Germany that use a robotic dispensing machine manufactured by ROWA during 2008. Method: Data concerning the financial and economic impact of using a robotic dispensing machine in community pharmacies was gathered using a structured questionnaire and analysed in terms of its financial implications. Key findings: The response rate was 29%. In most pharmacies (79%) the robotic dispensing machine was retrofitted. In 59% of the pharmacies additional space was gained for self-service and behind-the-counter display. As a result of using a robotic dispensing machine, personnel costs were reduced by an average of 4.6% during the first 12 months after start-up. Over-the-counter sales increased in the same period by an average of 6.8%. Despite average initial costs of 118,000 euros, total costs within the first 12 months fell in 50% of cases and at least remained the same in 44%. Conclusions: On average, robotic dispensing machines lead to modest savings in personnel costs and slight increases in sales of over-the-counter drugs. Substantial savings can be achieved only if the staffing level is adapted to the changed personnel requirements

Probing and characterizing the growth of a crystal of ultracold bosons and light

The non-linear coupled particle light dynamics of an ultracold gas in the field of two independent counter-propagating laser beams can lead to the dynamical formation of a self-ordered lattice structure as presented in (2016) Phys. Rev. X 6 021026. Here we present new numerical studies on experimentally observable signatures to monitor the growth and properties of such a crystal in real time. While, at least theoretically, optimal non-destructive observation of the growth dynamics and the hallmarks of the crystalline phase can be performed by analyzing scattered light, monitoring the evolution of the particle's momentum distribution via time-of-flight probing is an experimentally more accessible choice. In this work we show that both approaches allow us to unambiguously distinguish the crystal from independent collective scattering as it occurs in matter wave super-radiance. As a clear crystallization signature, we identify spatial locking between the two emerging standing laser waves, together creating the crystal potential. For sufficiently large systems, the system allows reversible adiabatic ramping into the crystalline phase as an alternative to a quench across the phase transition and growth from fluctuations

A History of the Improvement of Internet Protocols Over Satellites using ACTS

This paper outlines the main results of a number of ACTS experiments on the efficacy of using standard Internet protocols over long-delay satellite channels. These experiments have been jointly conducted by NASA\u27s Glenn Research Center and Ohio University over the last six years. The focus of our investigations has been the impact of long-delay networks with non-zero bit-error rates on the performance of the suite of Internet protocols. In particular, we have focused on the most widely used transport protocol, the Transmission Control Protocol (TCP), as well as several application layer protocols. This paper presents our main results, as well as references to more verbose discussions of our experiments

Arts therapies for anxiety, depression, and quality of life in breast cancer patients: A systematic review and meta-analysis

Background. Breast cancer is one of the most common types of cancer. However, only a few trials assess the effects of arts therapies. Material and Methods. We searched the Cochrane Central Register of Controlled Trials, PubMed, and Google Scholar from their start date to January 2012. We handsearched reference lists and contacted experts. All randomized controlled trials, quasi-randomized trials, and controlled clinical trials of art interventions in breast cancer patients were included. Data were extracted and risk of bias was assessed. Meta-analyses were performed using standardized mean differences. Results. Thirteen trials with a total of 606 patients were included. Arts therapies comprised music therapy interventions, various types of art therapy, and dance/movement therapies. The methodological quality ranged from poor to high quality with the majority scoring 3 of 4 points on the Jadad scale. Results suggest that arts therapies seem to positively affect patients' anxiety (standardized mean difference: -1.10; 95%, confidence interval: -1.40 to -0.80) but not depression or quality of life. No conclusion could be drawn regarding the effects of arts therapy on pain, functional assessment, coping, and mood states. Discussion. Our review indicates that arts interventions may have beneficial effects on anxiety in patients with breast cancer. © 2014 Katja Boehm et al