Hidden vortex lattices in a thermally paired superfluid

We study the evolution of rotational response of a hydrodynamic model of a two-component superfluid with a non-dissipative drag interaction, as the system undergoes a transition into a paired phase at finite temperature. The transition manifests itself in a change of (i) vortex lattice symmetry, and (ii) nature of vortex state. Instead of a vortex lattice, the system forms a highly disordered tangle which constantly undergoes merger and reconnecting processes involving different types of vortices, with a "hidden" breakdown of translational symmetry.Comment: 4 pages, 5 figs. Submitted to Physical Review. Online suppl. material available; Ref. 6. V2: Fig. 1 re-sent, URL in Ref. 6 correcte

Hydrogen atom in phase space. The Kirkwood-Rihaczek representation

We present a phase-space representation of the hydrogen atom using the Kirkwood-Rikaczek distribution function. This distribution allows us to obtain analytical results, which is quite unique because an exact analytical form of the Wigner functions corresponding to the atom states is not known. We show how the Kirkwood-Rihaczek distribution reflects properties of the hydrogen atom wave functions in position and momentum representations.Comment: 5 pages (and 5 figures

Scanning Electron Microscopy of the Accessory Sex Glands of the Adult Male Rat

This study describes the morphology of the accessory sex glands of the adult male rat as observed by scanning electron microscopy (SEM). The purpose was to obtain a systematic and comparative SEM description of these glands and to evaluate different preparation techniques. A common morphological feature is polyhedral delineation of the cells, which exhibited a variable convexity of their apical surface. The cell apices were more or less studded with microvilli. Nevertheless, it was possible to distinguish the glands by their surface morphology. In the ventral prostate, there was a considerable heterogeneity in cell surface appearance. The lateral lobe bad a characteristic brush border, and in the dorsal lobe, surface blebbing and intracellular cisternae were observed. The cells of the seminal vesicle were covered by long microvilli, while particularly distinct, elevated cell borders and intracellular cisternae were typical for the coagulating gland. The secretory mechanism was merocrine in the ventral and lateral prostate and the seminal vesicle, and was mainly apocrine in the dorsal prostate. Surprisingly, only merocrine secretion was obvious in the coagulating gland. The most controversial observation, which needs further investigation, was the discovery of large orifices in the apical surface of individual seminal vesicle cells. These orifices may be indicative of an additional apocrine secretion in this gland. In studying this organ system, SEM provides in-formation that adds to previous transmission electron microscopical investigations

Effects of Castration Upon the Morphology of the Accessory Sex Organs of the Male Rat - A Scanning Electron Microscopy Study

A systematic, comparative study of the accessory sex glands of the adult male rat after androgen withdrawal was carried out. The changes were investigated by using scanning electron microscopy at different intervals after surgical castration. The main common signs of epithelial cell involution were flattening of the cell surface, reduction of the size and number of microvilli, some blurring of the cell borders, cessation of secretory activity and diminution of the luminal volume of the glands. Overall, confident signs of atrophy were evident after one week, and complete epithelial involution was reached by the third week. The epithelial cell atrophy was accompanied by a relative stromal hyperplasia. The new observation seems to be that the process of stroma consolidation is progressing for a considerable time subsequent to the completion of the epithelial involution. This phenomenon is particularly evident in the dorsal prostate, the seminal vesicle and the coagulating gland

Evolutionary Approaches to Optimization Problems in Chimera Topologies

Chimera graphs define the topology of one of the first commercially available quantum computers. A variety of optimization problems have been mapped to this topology to evaluate the behavior of quantum enhanced optimization heuristics in relation to other optimizers, being able to efficiently solve problems classically to use them as benchmarks for quantum machines. In this paper we investigate for the first time the use of Evolutionary Algorithms (EAs) on Ising spin glass instances defined on the Chimera topology. Three genetic algorithms (GAs) and three estimation of distribution algorithms (EDAs) are evaluated over $1000$ hard instances of the Ising spin glass constructed from Sidon sets. We focus on determining whether the information about the topology of the graph can be used to improve the results of EAs and on identifying the characteristics of the Ising instances that influence the success rate of GAs and EDAs.Comment: 8 pages, 5 figures, 3 table

Differential gaze behavior towards sexually preferred and non-preferred human figures

The gaze pattern associated with image exploration is a sensitive index of our attention, motivation and preference. To examine whether an individual’s gaze behavior can reflect his/her sexual interest, we compared gaze patterns of young heterosexual men and women (M = 19.94 years, SD = 1.05) while viewing photos of plain-clothed male and female figures aged from birth to sixty years old. Our analysis revealed a clear gender difference in viewing sexually preferred figure images. Men displayed a distinctive gaze pattern only when viewing twenty-year-old female images, with more fixations and longer viewing time dedicated to the upper body and waist-hip region. Women also directed more attention at the upper body on female images in comparison to male images, but this difference was not age-specific. Analysis of local image salience revealed that observers’ eye-scanning strategies could not be accounted for by low-level processes, such as analyzing local image contrast and structure, but were associated with attractiveness judgments. The results suggest that the difference in cognitive processing of sexually preferred and non-preferred figures can be manifested in gaze patterns associated with figure viewing. Thus, eye-tracking holds promise as a potential sensitive measure for sexual preference, particularly in men

Unusual states of vortex matter in mixtures of Bose--Einstein Condensates on rotating optical lattices

A striking property of a single-component superfluid under rotation, is that a broken symmetry in the order parameter results in a broken translational symmetry, a vortex lattice. If translational symmetry is restored, the phase of the order parameter disorders and the broken symmetry in the order parameter is restored. We show that for Bose-Condensate mixtures on optical lattices (which may possess a negative dissipationless intercomponent drag), a new situation arises. A phase disordered nonsuperfluid component can break translational symmetry in response to rotation due to interaction with a superfluid component. This state is a modulated vortex liquid which breaks translational symmetry in the direction transverse to the rotation vector.Comment: 4 pages, 3 figures. To be published in Physical Review Letter

Validation of methods for monitoring of coastal and open sea areas with satellites and sensors on ships of opportunity

Årsliste 2003Final report to the Norwegian Research Council. The main objective of the project was to construct, install and test an automatic system for observations of temperature, salinity, chlorophyll fluorescence and turbidity from the cooling inlet aboard the ferry Color Festival (Oslo -Hirtshals). An automatic water sampler makes it possible to analyse other properties of the surface water, such as nutrients and organochlorides at selected positions. The potential of combined satellite and ship-sensor observations is illustrated as well as the use of the system for early warning of harmful algea. Examples are also given of the system's potential for low cost high frequency regular monitoring of the surface layer.Norwegian Research Counci

Suspension platform interferometer for the AEI 10\,m prototype: concept, design and optical layout

At present a 10\,m prototype interferometer facility is being set up at the AEI Hannover. One unique feature of the prototype will be the suspension platform interferometer (SPI). The purpose of the SPI is to monitor and stabilise the relative motion between three seismically isolated optical tables. The in-vacuum tables are suspended in an L-shaped configuration with an arm length of 11.65\,m. The design goal of the SPI is to stabilise longitudinal differential displacements to a level of 100\,pm/$\sqrt{\mathrm{Hz}}$ between 10\,mHz and 100\,Hz and relative angular noise of 10\,nrad/$\sqrt{\mathrm{Hz}}$ in the same frequency band. This paper covers the design aspects of the SPI, e.g. cross-coupling between the different degrees of freedom and fibre pointing noise are investigated. A simulation is presented which shows that with the chosen optical design of the SPI all degrees of table motion can be sensed in a fully decoupled way. Furthermore, a proof of principle test of the SPI sensing scheme is shown.Comment: 12 pages, 6 figure