A Waveguide for Bose-Einstein Condensates

We report on the creation of Bose-Einstein condensates of $^{87}$Rb in a specially designed hybrid, dipole and magnetic trap. This trap naturally allows the coherent transfer of matter waves into a pure dipole potential waveguide based on a doughnut beam. Specifically, we present studies of the coherence of the ensemble in the hybrid trap and during the evolution in the waveguide by means of an autocorrelation interferometer scheme. By monitoring the expansion of the ensemble in the waveguide we observe a mean field dominated acceleration on a much longer time scale than in the free 3D expansion. Both the autocorrelation interference and the pure expansion measurements are in excellent agreement with theoretical predictions of the ensemble dynamics

Images of a Bose-Einstein condensate in position and momentum space

In the Bogoliubov theory a condensate initially prepared in its ground state described by stationary Bogoliubov vacuum and later perturbed by a time-dependent potential or interaction strength evolves into a time-dependent excited state which is dynamical Bogoliubov vacuum. The dynamical vacuum has a simple diagonal form in a time-dependent orthonormal basis of single particle modes. This diagonal representation leads to a gaussian probability distribution for possible outcomes of density measurements in position and momentum space. In these notes we also discuss relations with the U(1) symmetry breaking version of the Bogoliubov theory and give two equivalent gaussian integral representations of the dynamical vacuum state.Comment: 4 pages; Talk given at the Laser Physics Workshop, July 2005, Kyoto, Japa

Photonic Crystal Nanobeam Cavity Strongly Coupled to the Feeding Waveguide

A deterministic design of an ultrahigh Q, wavelength scale mode volume photonic crystal nanobeam cavity is proposed and experimentally demonstrated. Using this approach, cavities with Q>10^6 and on-resonance transmission T>90% are designed. The devices fabricated in Si and capped with low-index polymer, have Q=80,000 and T=73%. This is, to the best of our knowledge, the highest transmission measured in deterministically designed, wavelength scale high Q cavities

Self-esteem and self-efficacy in the status attainment process and the multigenerational transmission of advantage

Despite considerable evidence of the importance of self-esteem and self-efficacy for agentic, goal-oriented behavior, little attention has been directed to these psychological dimensions in the status attainment literature. The present research uses data from the longitudinal, three-generation Youth Development Study (N = 422 three-generation triads) to examine the extent to which adolescent self-esteem and economic self-efficacy affect adult educational and income attainment, and whether these psychological resources are transmitted from one generation to the next, accumulating advantage across generations. We present evidence indicating that both self-esteem and economic self-efficacy are implicated in the attainment process. Adolescent economic self-efficacy had a direct positive effect on adult educational attainment and an indirect effect through educational plans. The influence of self-esteem on adult educational attainment was entirely indirect, through school achievement. We also find evidence that economic self-efficacy was transmitted from parents to children. We conclude that future research should more broadly consider psychological resources in attainment processes from a longitudinal multigenerational perspective

Molecular diversity of arbuscular mycorrhizal fungi in onion roots from organic and conventional farming systems in the Netherlands

Diversity and colonization levels of naturally occurring arbuscular mycorrhizal fungi (AMF) in onion roots were studied to compare organic and conventional farming systems in the Netherlands. In 2004, 20 onion fields were sampled in a balanced survey between farming systems and between two regions, namely, Zeeland and Flevoland. In 2005, nine conventional and ten organic fields were additionally surveyed in Flevoland. AMF phylotypes were identified by rDNA sequencing. All plants were colonized, with 60% for arbuscular colonization and 84% for hyphal colonization as grand means. In Zeeland, onion roots from organic fields had higher fractional colonization levels than those from conventional fields. Onion yields in conventional farming were positively correlated with colonization level. Overall, 14 AMF phylotypes were identified. The number of phylotypes per field ranged from one to six. Two phylotypes associated with the Glomus mosseae-coronatum and the G. caledonium-geosporum species complexes were the most abundant, whereas other phylotypes were infrequently found. Organic and conventional farming systems had similar number of phylotypes per field and Shannon diversity indices. A few organic and conventional fields had larger number of phylotypes, including phylotypes associated with the genera Glomus-B, Archaeospora, and Paraglomus. This suggests that farming systems as such did not influence AMF diversity, but rather specific environmental conditions or agricultural practice

Dual Ginzburg-Landau Theory for Nonperturbative QCD

Nonperturbative QCD is studied with the dual Ginzburg-Landau theory, where color confinement is realized through the dual Higgs mechanism by QCD-monopole condensation. We obtain a general analytic formula for the string tension. A compact formula is derived for the screened inter-quark potential in the presence of light dynamical quarks. The QCD phase transition at finite temperature is studied using the effective potential formalism. The string tension and the QCD-monopole mass are largely reduced near the critical temperature, $T_c$. The surface tension is estimated from the effective potential at $T_c$. We propose also a new scenario of the quark-gluon-plasma creation through the color-electric flux-tube annihilation. Finally, we discuss a close relation between instantons and QCD-monopoles.Comment: Talk presented by H. Suganuma at the Int. Conf. ``CONFINEMENT95'', March 22-24, 1995, Osaka, Japan, 12 pages, uses PHYZZ

A Generalized Diffusion Tensor for Fully Anisotropic Diffusion of Energetic Particles in the Heliospheric Magnetic Field

The spatial diffusion of cosmic rays in turbulent magnetic fields can, in the most general case, be fully anisotropic, i.e. one has to distinguish three diffusion axes in a local, field-aligned frame. We reexamine the transformation for the diffusion tensor from this local to a global frame, in which the Parker transport equation for energetic particles is usually formulated and solved. Particularly, we generalize the transformation formulas to allow for an explicit choice of two principal local perpendicular diffusion axes. This generalization includes the 'traditional' diffusion tensor in the special case of isotropic perpendicular diffusion. For the local frame, we motivate the choice of the Frenet-Serret trihedron which is related to the intrinsic magnetic field geometry. We directly compare the old and the new tensor elements for two heliospheric magnetic field configurations, namely the hybrid Fisk and the Parker field. Subsequently, we examine the significance of the different formulations for the diffusion tensor in a standard 3D model for the modulation of galactic protons. For this we utilize a numerical code to evaluate a system of stochastic differential equations equivalent to the Parker transport equation and present the resulting modulated spectra. The computed differential fluxes based on the new tensor formulation deviate from those obtained with the 'traditional' one (only valid for isotropic perpendicular diffusion) by up to 60% for energies below a few hundred MeV depending on heliocentric distance.Comment: 8 pages, 6 figures, accepted in Ap

Levels of Polychlorinated Biphenyls (PCBs) and Three Organochlorine Pesticides in Fish from the Aleutian Islands of Alaska

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and chlorinated pesticides, have been shown to have many adverse human health effects. These contaminants therefore may pose a risk to Alaska Natives that follow a traditional diet high in marine mammals and fish, in which POPs bioaccumulate.This study examined the levels of PCBs and three pesticides [p, p'-DDE, mirex, and hexachlorobenzene (HCB)] in muscle tissue from nine fish species from several locations around the Aleutian Islands of Alaska. The highest median PCB level was found in rock sole (Lepidopsetta bilineata, 285 ppb, wet weight), while the lowest level was found in rock greenling (Hexagrammos lagocephalus, 104 ppb, wet weight). Lipid adjusted PCB values were also calculated and significant interspecies differences were found. Again, rock sole had the highest level (68,536 ppb, lipid weight). Concerning the PCB congener patterns, the more highly chlorinated congeners were most common as would be expected due to their greater persistence. Among the pesticides, p, p'-DDE generally dominated, and the highest level was found in sockeye salmon (Oncorhynchus nerka, 6.9 ppb, wet weight). The methodology developed by U.S. Environmental Protection Agency (USEPA) was used to calculate risk-based consumption limits for the analyzed fish species. For cancer health endpoints for PCBs, all species would trigger strict advisories of between two and six meals per year, depending upon species. For noncancer effects by PCBs, advisories of between seven and twenty-two meals per year were triggered. None of the pesticides triggered consumption limits.The fish analyzed, mainly from Adak, contain significant concentrations of POPs, in particular PCBs, which raises the question whether these fish are safe to eat, particularly for sensitive populations. However when assessing any risk of the traditional diet, one must also consider the many health and cultural benefits from eating fish

Desperate housewives: An analysis of the characterisations of female gamblers portrayed in gambling movies in Hong Kong

This article examines portrayals of female gamblers in recent Hong Kong movies. The authors report that the depiction of female gamblers is very different from that of male gamblers in the movies made in the same period. Whereas the male gamblers are pitching a lonely and desperate battle against the evil opponent, the female gamblers portrayed in the movies are housewives or small-time players who gamble only for their personal gain. A general negative overtone in portrayals of female gamblers was interpreted as a reflection of the traditional view that discourages women from gambling. The shift of gambling themes in the Hong Kong movies has been identified to reflect the most salient concerns among Hong Kong residents. Such changes are attributed to particular social and cultural changes in the community