Liquid FM: Recommending Music through Viscous Democracy

Most modern recommendation systems use the approach of collaborative filtering: users that are believed to behave alike are used to produce recommendations. In this work we describe an application (Liquid FM) taking a completely different approach. Liquid FM is a music recommendation system that makes the user responsible for the recommended items. Suggestions are the result of a voting scheme, employing the idea of viscous democracy. Liquid FM can also be thought of as the first testbed for this voting system. In this paper we outline the design and architecture of the application, both from the theoretical and from the implementation viewpoints

Pericentromeric heterochromatin is hierarchically organized and spatially contacts H3K9me2 islands in euchromatin.

Membraneless pericentromeric heterochromatin (PCH) domains play vital roles in chromosome dynamics and genome stability. However, our current understanding of 3D genome organization does not include PCH domains because of technical challenges associated with repetitive sequences enriched in PCH genomic regions. We investigated the 3D architecture of Drosophila melanogaster PCH domains and their spatial associations with the euchromatic genome by developing a novel analysis method that incorporates genome-wide Hi-C reads originating from PCH DNA. Combined with cytogenetic analysis, we reveal a hierarchical organization of the PCH domains into distinct territories. Strikingly, H3K9me2-enriched regions embedded in the euchromatic genome show prevalent 3D interactions with the PCH domain. These spatial contacts require H3K9me2 enrichment, are likely mediated by liquid-liquid phase separation, and may influence organismal fitness. Our findings have important implications for how PCH architecture influences the function and evolution of both repetitive heterochromatin and the gene-rich euchromatin

Improving the mesomorphic behaviour of supramolecular liquid crystals by resonance-assisted hydrogen bonding

A systematic structure-property relationship study on hydrogen-bonded liquid crystals was performed, revealing the impact of resonance-assisted hydrogen bonds (RAHBs) on the self-assembling behavior of the supramolecular architecture. The creation of a six-membered intramolecular hydrogen-bonded ring acts as a counterpart to the self-organization between hydrogen bond donators and acceptors and determines thus the suprastructure. Variation of the hydrogen-bonding pattern allowed us to significantly improve the temperature range of the reported liquid crystalline assemblies

100 GHz electrically tunable planar Bragg grating via nematic liquid crystal overlay towards reconfigurable WDM networks

Novel liquid crystal-based integrated optical devices with >140GHz electrical tuning are presented for application towards reconfigurable wavelength division multiplexing (WDM) networks. Initial results with Bragg wavelength tuning covering five 25GHz WDM channel spacing have been achieved with 170V (peak-to-peak) sinusoidal voltages applied across electro-patterned ITO-covered glass electrodes placed 60µm apart. These prototype devices were fabricated using direct UV grating writing, with an evanescent field coupling into a liquid crystal overlay through an etched window. Electrically controlled liquid crystal birefringence modifies the waveguide effective index, resulting in Bragg wavelength shift. Merck 18523 nematic liquid crystals are used, exhibiting compatible refractive index values to that of silica (no=1.44, ne=1.49 at lambda=1550nm). Homeotropic alignment of the liquid crystal is provided by application of a surfactant layer.The inherent refractive index sensitivity of our etched direct-UV-written structures allows observation of previously unreported liquid crystal surface-behaviour, such as multi-threshold points during variation of the applied field. Continued optimisation based on evanescent field penetration, electrode layout, and surface interaction will allow implementation towards a variety of novel liquid crystal applications and devices. For example, a cascaded architecture of these integrated liquid crystal devices operating at different Bragg wavelengths would pave the way towards true colorless add/drop modules for dense optical networks

Tuned liquid dampers simulation for earthquake response control of buildings

This paper is focused on the study of an earthquake protection system, the Tuned Liquid Damper (TLD), which can, if adequately designed, reduce earthquake demands on buildings. This positive effect is accomplished taking into account the oscillation of the free surface of a fluid inside a tank (sloshing). The behaviour of an isolated Tuned Liquid Damper, subjected to a sinusoidal excitation at its base, with different displacement amplitudes, was studied by finite element analysis. The efficiency of the TLD in improving the seismic response of an existing building, representative of modern architecture buildings in southern European countries was also evaluated based on linear dynamic analyses

Liquid-gas-solid flows with lattice Boltzmann: Simulation of floating bodies

This paper presents a model for the simulation of liquid-gas-solid flows by means of the lattice Boltzmann method. The approach is built upon previous works for the simulation of liquid-solid particle suspensions on the one hand, and on a liquid-gas free surface model on the other. We show how the two approaches can be unified by a novel set of dynamic cell conversion rules. For evaluation, we concentrate on the rotational stability of non-spherical rigid bodies floating on a plane water surface - a classical hydrostatic problem known from naval architecture. We show the consistency of our method in this kind of flows and obtain convergence towards the ideal solution for the measured heeling stability of a floating box.Comment: 22 pages, Preprint submitted to Computers and Mathematics with Applications Special Issue ICMMES 2011, Proceedings of the Eighth International Conference for Mesoscopic Methods in Engineering and Scienc

Liquid Architecture 8 Sydney

Background Liquid Architecture, Australia's national festival of sound arts, made a successful Sydney debut in 2005, developing audiences for sound art through diverse, high quality programming. 2006 saw the challenge of growing the festival while maintaining quality and critical focus. Contribution In addition to previously included forms such as musique concrete and free improvisation, Liquid Architecture 7 Sydney expanded its policy of developing audiences through inclusivity by embracing sound poetry (Amanda Stewart), the contemporary classical world of New Music (composers Ros Bandt, Garth Paine and Michael Atherton) as well as new international connections, through the 'Swiss Australian Collectibles', an international project between Swiss composers and Melbourne musicians. The program of artist talks was also expanded to include panel discussions and instrument building workshops and masterclasses. Significance Tony Osborne, writing in RealTime, said that the festival "set up exciting juxtapositions and provoked plenty of interesting debate" which means that the festival achieved its curatorial goals, building on its previous success and continuing to attract and develop audiences with new work and opportunities to engage with sound in its many forms

Destroying a topological quantum bit by condensing Ising vortices

The imminent realization of topologically-protected qubits in fabricated systems will provide not only an elementary implementation of fault-tolerant quantum computing architecture, but also an experimental vehicle for the general study of topological order. The simplest topological qubit harbors what is known as a Z$_2$ liquid phase, which encodes information via a degeneracy depending on the system's topology. Elementary excitations of the phase are fractionally charged objects called {\it spinons}, or Ising flux vortices called {\it visons}. At zero temperature a Z$_2$ liquid is stable under deformations of the Hamiltonian until spinon or vison condensation induces a quantum phase transition destroying the topological order. In this paper, we use quantum Monte Carlo to study a vison-induced transition from a Z$_2$ liquid to a valence-bond solid in a quantum dimer model on the kagome lattice. Our results indicate that this critical point is controlled by a new universality class beyond the standard Landau paradigm.Comment: 5 pages, 4 figures. Published versio