Simulating Quantum Magnetism with Correlated Non-Neutral Ion Plasmas

By employing forces that depend on the internal electronic state (or spin) of an atomic ion, the Coulomb potential energy of a strongly coupled array of ions can be modified in a spin-dependent way to mimic effective quantum spin Hamiltonians. Both ferromagnetic and antiferromagnetic interactions can be implemented. We use simple models to explain how the effective spin interactions are engineered with trapped-ion crystals. We summarize the type of effective spin interactions that can be readily generated, and discuss an experimental implementation using single-plane ion crystals in a Penning trap.Comment: 10 pages, 5 figures, to be published in the Proceedings of 10th International Workshop on Non-Neutral Plasma

Protostellar Feedback Processes and the Mass of the First Stars

We review theoretical models of Population III.1 star formation, focusing on the protostellar feedback processes that are expected to terminate accretion and thus set the mass of these stars. We discuss how dark matter annihilation may modify this standard feedback scenario. Then, under the assumption that dark matter annihilation is unimportant, we predict the mass of stars forming in 12 cosmological minihalos produced in independent numerical simulations. This allows us to make a simple estimate of the Pop III.1 initial mass function and how it may evolve with redshift.Comment: 6 pages, Proceedings of 'The First Stars and Galaxies: Challenges for the Next Decade", Austin, TX, March 8-11, 201

There’s more to us than this: A qualitative study of Black young adults’ perceptions of media portrayals of HIV

The extent to which the targeted group attends to and is engaged by HIV/STI prevention messages is one component of effective health communication. Through an empirical examination of the cumulative perceptions of HIV/STI prevention media messages targeted to Black youth and young adults, this qualitative study privileges the voices of Black/ African American young adults as a group that is frequently targeted in HIV prevention campaigns. Semi-structured interviews with 23 Black/African American young adults yielded key themes that suggest barriers to effective health communication. Traditionally, health promotion has advocated for targeted messages as a means to increase risk perception and promote behavior change. For some study participants, the unintended consequences of this approach with HIV prevention included a perception that cumulatively media messages (1) portrayed HIV as a “Black disease; (2) blamed Black people for the HIV epidemic; and (3) fostered negative judgments about Black people. Participants described mixed feelings because they perceived that the messages simultaneously increased awareness for HIV prevention in the Black community as well as perpetuated stigma of the Black community. The findings challenge existing notions about targeting health communication particularly when focusing on stigmatized illnesses

History as neurosis: Psychoanalysis and Marxism in Édouard Glissant’s Le Discours antillais

In Le Discours antillais (1981) Glissant analyses the alienation of the Martiniquan people within both a psychoanalytical and a Marxist perspective. He argues that they have repressed their consciousness of their history, so that their relation to it is neurotic. He considers psychosis to be in some sense less negative, because it is an escape from repression. But he also uses Marxism because he believes that the current state of the society derives from economic factors, specifically the collapse of the sugar cane industry: and since Martinique has no ‘real’ economy, it can have no ‘real’ social classes either. His use of both theoretical approaches is compared with the positions of Lacan and Althusser

A Case Study of the Population Ecology of a Topmouth Gudgeon (Pseudorasbora parva) Population in the UK and the Implication for Native Fish Communities

1. The topmouth gudgeon Pseudorasbora parva is a small Asian cyprinid species that has proved invasive throughout many European countries. Following an initial introduction into the wild in 1996, the species is now proving invasive in the UK, with at least 25 infested waters in England and Wales, of which 10 are known to have direct connection to a major river catchment. 2. To demonstrate the threat of P. parva to fisheries in the UK, a case study is presented on a lake located in the Lake District of England where the species was introduced in 2000. The species rapidly established a breeding population that, by 2003, was the dominant species in size classes <70 mm. In 2004, they were the only species in the lake that produced young-of-the-year. 3. Individual P. parva adopted the reproductive tactics of early maturity, multiple spawning, male dominance and male nest guarding; sexual dimorphism was manifested in larger body size of males. These traits were in contrast to the resident, native species of the lake, including roach Rutilus rutilus and gudgeon Gobio gobio, which adopted traits of later maturity and single spawning. 4. This case study, therefore, revealed relatively rapid establishment of a P. parva population, their subsequent numerical dominance of the fish community, and the impediment of the recruitment of native fish. The implications for UK fisheries are concerning: should P. parva continue to disperse and individuals adopt similar traits as those in this case study, there may be few waters immune from their invasion, numerical dominance and subsequent impacts

Arroyo

Arroyo is an open source, cross-platform C++ class library project designed for modeling of electromagnetic wave propagation through atmospheric turbulence and adaptive optics systems. This paper describes the functionality available in the library and discusses future plans for this project

Numerical simulations of single conjugate adaptive optics systems

This paper presents a series of studies of single conjugate adaptive optics systems that use numerical simulation to investigate aspects of system performance not addressed by traditional statistical metrics. These studies include investigations of temporal control loop dynamics and quantitative comparisons of system performance using different types of reconstructors

Differential expression of microRNAs in bovine papillomavirus type 1 transformed equine cells

Bovine papillomavirus (BPV) types 1 and 2 play an important role in the pathogenesis of equine sarcoids (ES), the most common cutaneous tumour affecting horses. MicroRNAs (miRNAs), small non-coding RNAs that regulate essential biological and cellular processes, have been found dysregulated in a wide range of tumours. The aim of this study was to identify miRNAs associated with ES. Differential expression of miRNAs was assessed in control equine fibroblasts (EqPalFs) and EqPalFs transformed with the BPV-1 genome (S6-2 cells). Using a commercially available miRNA microarray, 492 mature miRNAs were interrogated. In total, 206 mature miRNAs were differentially expressed in EqPalFs compared with S6-2 cells. Aberrant expression of these miRNAs in S6-2 cells can be attributed to the presence of BPV-1 genomes. Furthermore, we confirm the presence of 124 miRNAs previously computationally predicted in the horse. Our data supports the involvement of miRNAs in the pathogenesis of ES