Structure and far-infrared edge modes of quantum antidots at zero magnetic field

We have investigated edge modes of different multipolarity sustained by quantum antidots at zero magnetic field. The ground state of the antidot is described within a local-density-functional formalism. Two sum rules, which are exact within this formalism, have been derived and used to evaluate the energy of edge collective modes as a function of the surface density and the size of the antidot.

Edge excitations and topological order in rotating Bose gas

The edge excitations and related topological orders of correlated states of a fast rotating Bose gas are studied. Using exact diagonalization of small systems, we compute the energies and number of edge excitations, as well as the boson occupancy near the edge for various states. The chiral Luttinger-liquid theory of Wen is found to be a good description of the edges of the bosonic Laughlin and other states identified as members of the principal Jain sequence for bosons. However, we find that in a harmonic trap the edge of the state identified as the Moore-Read (Pfaffian) state shows a number of anomalies. An experimental way of detecting these correlated states is also discussed.

Bound states of 3He at the edge of a 4He drop on a cesium surface

We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andreev states that appear at the free surface and at the liquid-solid interface of films. We illustrate the one-body density of 3He in a drop with 1000 4He atoms, and show that for a sufficiently large number of impurities the density profiles spread beyond the edge, coating both the curved drop surface and its flat base and eventually isolating it from the substrate.

Thermal and back-action noises in dual-sphere gravitational-wave detectors

We study the sensitivity limits of a broadband gravitational-wave detector based on dual resonators such as nested spheres. We determine both the thermal and back-action noises when the resonators displacements are read out with an optomechanical sensor. We analyze the contributions of all mechanical modes, using a new method to deal with the force-displacement transfer functions in the intermediate frequency domain between the two gravitational-wave sensitive modes associated with each resonator. This method gives an accurate estimate of the mechanical response, together with an evaluation of the estimate error. We show that very high sensitivities can be reached on a wide frequency band for realistic parameters in the case of a dual-sphere detector.

People on the Edge See More. A conversation with the cuban-american writer Cristina García

L'entrevista amb l'escriptora cubano-americana Cristina García explora el tema de la identitat cubanoamericana i desvetlla la riquesa literària que sorgeix de la fusió de dues cultures, la cubana i la nord-americana, i com aquesta fusió innova la literatura nord-americana tradicional. En la seva novel·la, Dreaming in Cuban (1992), l'escriptora explora els efectes de la Revolució castrista des de la perspectiva de les dones cubanes que van quedar-se a l'illa, així com de les dones que emigraren als Estats Units. The conversation with Cuban-American writer Cristina García explores what it means to be Cuban-American, and reveals how to grow bicultural enriches mainstream American literature. In her novel Dreaming in Cuban (1992), the writer explores the effects of the Castro Revolution from the perspective of Cuban women who remained in Cuba, as well as from the experience of women who emigrated to the United States.

People on the Edge See More. A conversation with the cuban-american writer Cristina García

L'entrevista amb l'escriptora cubano-americana Cristina García explora el tema de la identitat cubanoamericana i desvetlla la riquesa literària que sorgeix de la fusió de dues cultures, la cubana i la nord-americana, i com aquesta fusió innova la literatura nord-americana tradicional. En la seva novel·la, Dreaming in Cuban (1992), l'escriptora explora els efectes de la Revolució castrista des de la perspectiva de les dones cubanes que van quedar-se a l'illa, així com de les dones que emigraren als Estats Units. The conversation with Cuban-American writer Cristina García explores what it means to be Cuban-American, and reveals how to grow bicultural enriches mainstream American literature. In her novel Dreaming in Cuban (1992), the writer explores the effects of the Castro Revolution from the perspective of Cuban women who remained in Cuba, as well as from the experience of women who emigrated to the United States.

Cutting edge: cell autonomous rather than environmental factors control bacterial superantigen-induced T cell anergy in vivo.

Anergic T cells display a marked decrease in their ability to produce IL-2 and to proliferate in the presence of an appropriate antigenic signal. Two nonmutually exclusive classes of models have been proposed to explain the persistence of T cell anergy in vivo. While some reports indicate that anergic T cells have intrinsic defects in signaling pathways or transcriptional activities, other studies suggest that anergy is maintained by environmental "suppressor" factors such as cytokines or Abs. To distinguish between these conflicting hypotheses, we employed the well-characterized bacterial superantigen model system to evaluate in vivo the ability of a trace population of adoptively transferred naive or anergized T cells to proliferate in a naive vs anergic environment upon subsequent challenge. Our data clearly demonstrate that bacterial superantigen-induced T cell anergy is cell autonomous and independent of environmental factors.

Statistical mechanics of multi-edge networks

Statistical properties of binary complex networks are well understood and recently many attempts have been made to extend this knowledge to weighted ones. There are, however, subtle yet important considerations to be made regarding the nature of the weights used in this generalization. Weights can be either continuous or discrete magnitudes, and in the latter case, they can additionally have undistinguishable or distinguishable nature. This fact has not been addressed in the literature insofar and has deep implications on the network statistics. In this work we face this problem introducing multiedge networks as graphs where multiple (distinguishable) connections between nodes are considered. We develop a statistical mechanics framework where it is possible to get information about the most relevant observables given a large spectrum of linear and nonlinear constraints including those depending both on the number of multiedges per link and their binary projection. The latter case is particularly interesting as we show that binary projections can be understood from multiedge processes. The implications of these results are important as many real-agent-based problems mapped onto graphs require this treatment for a proper characterization of their collective behavior.

Stabilization Procedures to Mitigate Edge Rutting for Granular Shoulders - Phase II, TR-591, 2011

A multifaceted investigation was undertaken to develop recommendations for methods to stabilize granular road shoulders with the goal of mitigating edge ruts. Included was reconnaissance of problematic shoulder locations, a laboratory study to develop a method to test for changes in granular material stability when stabilizing agents are used, and the construction of three sets of test sections under traffic at locations with problematic granular shoulders. Full results of this investigation are included in this report and its appendices. This report also presents conclusions and recommendations based on the study results.

Height distributions of Scots pine sapling stands affected by retained tree and edge stand competition

Abstract

Traffic Control in Work Zones with Edge Drop-Offs, 2002

Pavement and shoulder edge drop-offs commonly occur in work zones as the result of overlays, pavement replacement, or shoulder construction. The depth of these elevation differentials can vary from approximately one inch when a flexible pavement overlay is applied to several feet where major reconstruction is undertaken. The potential hazards associated with pavement edge differentials depend on several factors including depth of the drop-off, shape of the pavement edge, distance from traveled way, vehicle speed, traffic mix, volume, and other factors. This research was undertaken to review current practices in other states for temporary traffic control strategies addressing lane edge differentials and to analyze crash data and resultant litigation related to edge drop-offs. An objective was to identify cost-effective practices that would minimize the potential for and impacts of edge drop crashes in work zones. Considerable variation in addressing temporary traffic control in work zones with edge drop-off exposure was found among the states surveyed. Crashes related to pavement edge drop-offs in work zones do not commonly occur in the state of Iowa, but some have resulted in significant tort claims and settlements. The use of benefit/cost analysis may provide guidance in selection of an appropriate mitigation and protection of edge drop-off conditions. Development and adoption of guidelines for design of appropriate traffic control for work zones that include edge drop-off exposure, particularly identifying effective use of temporary barrier rail, may be beneficial in Iowa.

Dynamic range extension of SiPM detectors with the time-gated operation

The silicon photomultiplier (SiPM) is a novel detector technology that has undergone a fast development in the last few years, owing to its single-photon resolution and ultra-fast response time. However, the typical high dark count rates of the sensor may prevent the detection of low intensity radiation fluxes. In this article, the time-gated operation with short active periods in the nanosecond range is proposed as a solution to reduce the number of cells fired due to noise and thus increase the dynamic range. The technique is aimed at application fields that function under a trigger command, such as gated fluorescence lifetime imaging microscopy.

Cutting edge: stimulation with the cognate self-antigen induces expression of the Ly49A receptor on self-reactive T cells which modulates their responsiveness.

NK cell self-tolerance is maintained by inhibitory receptors specific for MHC class I molecules. Inhibitory NK receptors are also expressed on memory CD8 T cells but their biological relevance on T cells is unclear. In this study, we describe the expression of the Ly49A receptor on a subset of autoreactive T cells which persist in mice double-transgenic for the lymphocytic choriomeningitis virus-derived peptide gp33 and a TCRalphabeta specific for the gp33. No Ly49A-expressing cells are found in TCRalphabeta single-transgenic mice, indicating that the presence of the autoantigen is required for Ly49A induction. Direct evidence for an Ag-specific initiation of Ly49A expression has been obtained in vitro after stimulation of autoreactive TCRalphabeta T cells with the cognate self-Ag. This expression of Ly49A substantially reduces Ag-specific activation of autoreactive T cells. These findings thus suggest that autoantigen-specific induction of inhibitory NK cell receptors on T cells may contribute to peripheral self-tolerance.

Cutting edge: alum adjuvant stimulates inflammatory dendritic cells through activation of the NALP3 inflammasome.

Adjuvants are vaccine additives that stimulate the immune system without having any specific antigenic effect of itself. In this study we show that alum adjuvant induces the release of IL-1beta from macrophages and dendritic cells and that this is abrogated in cells lacking various NALP3 inflammasome components. The NALP3 inflammasome is also required in vivo for the innate immune response to OVA in alum. The early production of IL-1beta and the influx of inflammatory cells into the peritoneal cavity is strongly reduced in NALP3-deficient mice. The activation of adaptive cellular immunity to OVA-alum is initiated by monocytic dendritic cell precursors that induce the expansion of Ag-specific T cells in a NALP3-dependent way. We propose that, in addition to TLR stimulators, agonists of the NALP3 inflammasome should also be considered as vaccine adjuvants.