Texture control in a pseudospin Bose-Einstein condensate

We describe a wavefunction engineering approach to the formation of textures in a two-component nonrotated Bose-Einstein condensate. By controlling the phases of wavepackets that combine in a three-wave interference process, a ballistically-expanding regular lattice-texture is generated, in which the phases determine the component textures. A particular example is presented of a lattice-texture composed of half-quantum vortices and spin-2 textures. We demonstrate the lattice formation with numerical simulations of a viable experiment, identifying the textures and relating their locations to a linear theory of wavepacket interference.Comment: 4 pages, 5 figures, REVTeX4-

Biochemistry as a Liberal Art

One now routinely learns of a university theatre department closed here, a philosophy department closed there, of budget pressure that has forced the cancellation of this language program, or how funding cutbacks have permitted that fine arts department to continue to function, but only with sessional faculty. The sciences (of course?) have been largely spared. But how ought science faculty to respond to the philosophical questions involved in the cultural squeeze on their colleagues? Herein I argue that science faculty ought to be as outraged as they are: what is at stake is the cultural understanding of the meaning and purpose of all education. Will the university devolve into an institution whose purpose is entirely vocational in character? Probably most students already regard it as such, as do some faculty. Using examples from my own discipline – biochemistry – I develop the thesis that to increase emphasis on the epistemological, cosmological, natural historical, and humanistic elements of science disciplines is a defense of education as more-than-training, a partial corrective to the erosion of the liberal arts tradition, and, indeed, an enrichment of the science curriculum itself

HIV-1 infection of microglial cells in a reconstituted humanized mouse model and identification of compounds that selectively reverse HIV latency.

Most studies of HIV latency focus on the peripheral population of resting memory T cells, but the brain also contains a distinct reservoir of HIV-infected cells in microglia, perivascular macrophages, and astrocytes. Studying HIV in the brain has been challenging, since live cells are difficult to recover from autopsy samples and primate models of SIV infection utilize viruses that are more myeloid-tropic than HIV due to the expression of Vpx. Development of a realistic small animal model would greatly advance studies of this important reservoir and permit definitive studies of HIV latency. When radiation or busulfan-conditioned, immune-deficient NSG mice are transplanted with human hematopoietic stem cells, human cells from the bone marrow enter the brain and differentiate to express microglia-specific markers. After infection with replication competent HIV, virus was detected in these bone marrow-derived human microglia. Studies of HIV latency in this model would be greatly enhanced by the development of compounds that can selectively reverse HIV latency in microglial cells. Our studies have identified members of the CoREST repression complex as key regulators of HIV latency in microglia in both rat and human microglial cell lines. The monoamine oxidase (MAO) and potential CoREST inhibitor, phenelzine, which is brain penetrant, was able to stimulate HIV production in human microglial cell lines and human glial cells recovered from the brains of HIV-infected humanized mice. The humanized mice we have developed therefore show great promise as a model system for the development of strategies aimed at defining and reducing the CNS reservoir

Photoacoustic ultrasound sources from diffusion-limited aggregates

Metallic diffusion-limited aggregate (DLA) films are well-known to exhibit near-perfect broadband optical absorption. We demonstrate that such films also manifest a substantial and relatively material-independent photoacoustic response, as a consequence of their random nanostructure. We theoretically and experimentally analyze photoacoustic phenomena in DLA films, and show that they can be used to create broadband air- coupled acoustic sources. These sources are inexpensive and simple to fabricate, and work into the ultrasonic regime. We illustrate the device possibilities by building and testing an optically-addressed acoustic phased array capable of producing virtually arbitrary acoustic intensity patterns in air.Comment: 5 pages, 5 figure

Nursing Home Residents and the New California Health Care Decisions Law

This article explores issues involving advance directives made by nursing home residents, both prior to and during their stay in a facility, including the frequency of making directives, the reasons why residents fail to make directives, and the reasons why facilities often fail to honor them. Specifically, this article examines these issues in light of the 1999 California Health Care Decisions Law, effective July 1, 2000, and focuses on how this new statute can be used to empower nursing home residents, and adults more generally, to take control of decisions regarding their own health care

University counseling centers and student vets

posterMental health care is changing, as are the needs of student veterans, placing stress upon current mental health care models. As such, this study looked at the potential ability of university and counseling centers to meet the needs of student military veterans in transitioning to college life and dealing with any particular mental health issues ranging from depression to PTSD

A stochastic movement model reproduces patterns of site fidelity and long-distance dispersal in a population of Fowler’s toads (Anaxyrus fowleri)

Although amphibians typically exhibit high site fidelity and low dispersal, they do undertake rare, long-distance movements. The factors influencing these events remain poorly understood, partly because amphibian spring movements tend to radiate from breeding sites and the animals are often difficult to locate at other times of the year. In this study, we investigate whether these movement patterns can be reproduced by a parsimonious model where foraging steps follow a heavy-tailed, Lévy alpha-stable distribution and individuals may either return to a previous refuge site or establish a new one. We consider three versions of the return behaviour: (1) a distance-independent probability of return to any previous refuge; (2) constant probability of return to the nearest refuge; or (3) a distance-dependent probability of return to each refuge. Using approximate Bayesian computation, we fit each version of the model to radiotracking data from a population of Fowler's Toads, which inhabits a linear sand dune habitat on the north shore of Lake Erie in Ontario, Canada. Only the model with distance-independent, random returns provides a good fit of the inter-refuge distance distribution and the number of refuges visited per toad. Our results suggest that while toads occasionally forage over long distances, the establishment of new refuges is not driven by the minimization of energy expenditure