A gesturally controlled improvisation system for piano

This paper was presented at the Live Interfaces conference 2012. Copyright @ 2012 The Authors.This paper presents a gesturally controlled, live-improvisation system, developed for an experimental pianist and used during a performance at the 2011 International Conference on New Interfaces for Musical Expression. We describe the gesture-recognition architecture used to recognize the pianist’s real-time gestures, the audio infrastructure developed specifically for this piece and the core lessons learned over the process of developing this performance system

Nanotoxicity of polyelectrolyte-functionalized titania nanoparticles towards microalgae and yeast: Role of the particle concentration, size and surface charge

We studied the nanotoxicity of titania nanoparticles (TiO₂NPs) of various hydrodynamic diameters and crystallite sizes towards C. reinhardtii microalgae and S. cerevisiae (yeast) upon illumination with UV and visible light. The cell viability was assessed for a range of nanoparticle concentrations and incubation times. We found that bare TiO₂NPs affect the C. reinhardtii cell viability at much lower particle concentrations than for yeast. We observed an increase of the TiO₂NPs toxicity upon illumination with UV light compared with that in dark conditions due to the oxidative stress of the produced reactive oxygen species. We also found an increased TiO₂NPs nanotoxicity upon illumination with visible light which indicates that they may also interfere with the microalgae's photosynthetic system leading to decreased chlorophyll content upon exposure to TiO₂NPs. The results indicate that the larger the hydrodynamic diameter of the TiO₂NPs the lower is their nanotoxicity, with anatase TiO₂NPs generally being more toxic than rutile TiO₂NPs. We also prepared a range of polyelectrolyte-coated TiO₂NPs using a layer by-layer method and studied their nanotoxicity towards yeast and microalgae. We found that the toxicity of the coated TiO₂NPs changes with their surface charge. TiO₂NPs coated with cationic polyelectrolyte as an outer layer exhibit much higher nanotoxicity than the ones with an outer layer of anionic polyelectrolyte. TEM images of sectioned microalgae and yeast cells exposed to different polyelectrolyte-coated TiO₂NPs confirmed the formation of a significant build-up of nanoparticles on the cell surface for bare and cationic polyelectrolyte-coated TiO₂NPs. The effect comes from the increased adhesion of cationic nanoparticles to the cell walls. Significantly, coating the TiO₂NPs with anionic polyelectrolyte as an outer layer led to a reduced adhesion and much lower nanotoxicity due to electrostatic repulsion with the cell walls. This suggest a new way of making cationic TiO₂NPs safer for use in different formulations by pre-coating them with anionic polyelectrolytes. The results of this study give important insights into the various factors controlling the nanotoxicity of TiO₂NPs

Distribution patterns, weed incursions and origins of terrestrial flora at the Capricorn-Bunker Islands, Great Barrier Reef, Australia

A checklist of vascular plants of the 15 Capricorn-Bunker Islands (CBI) (lat 23° 11’ to 24° 07’S; long 151° 43’ to 152° 43’E) compiled from 2007/08 surveys, recorded 131 vascular plant species including 44 (34%) native and 87 (66%) naturalized species from 55 families and 104 genera. New native records include Hernandia nymphaeifolia and Boerhavia sp. (Bargara L.Pedley 5382). An increase of about 35 exotic species over 23 years was recorded indicating a weed incursion rate of 1.5 species per annum. Cakile edentula (13 islands) and Solanum americanum (12 islands) are the most widespread exotic weeds. The naturalised flora ranged from 5% at Erskine Island (low disturbance) to 68% at Lady Elliot Island (very high disturbance). Achyranthes aspera, Argusia argentea and Pisonia grandis are the only species found on all 15 islands. Six indigenous species are limited to one island: Boerhavia sp. (Bargara L.Pedley 5382), Calophyllum inophyllum, Clerodendrum inerme, Hernandia nymphaeifolia, Stephania japonica and Ximenia americana. Patterns of plant distributions, diversity and origin are discussed. Eleven indigenous species reach their southern limit at the CBI, indicating connectivity with the Indo-Pacific region. PATN analyses using native flora generated two island groups. Tryon, Heron, North West, Masthead, Wilson, Wreck and Erskine Islands are the most closely related islands. Another group of related islands includes North Reef, Lady Musgrave, Fairfax Islands, Hoskyn and One Tree Islands. With the inclusion of the exotic flora, Lady Elliot Island separated into its own distinct group. Greater conservation management efforts are required to control and minimise the introduction of exotic weed species to islands with high human visitation

Plant strategies, dispersal and origins of flora at the northern Coral Sea Islands Territory, Australia

A checklist of vascular plants of Coringa-Herald National Nature Reserve (CHNNR) (17º 11’S, 149º 00’ E to 16º 23’S, 150º 30’E and Willis Island (16º 24’S, 149º 58’E) at the northern Coral Sea Islands Territory of Australia compiled during 2006/07 surveys, recorded 30 species including 18 species indigenous to the Coral Sea Islands (60%), 10 exotic species (33%) and two that were planted (7%). Plant life-forms included: 5 species of trees and tall shrubs (17%), 2 species of low shrubs (6.5%), 21 herbs (70%), and 2 vine/creepers (6.5%). Plant dispersal for the 30 species is predominantly by human activities (40%), ocean currents (33%) and seabirds (27%). The garden species and dispersal modes at Willis Island indicate that non-residential casual human visitation at CHNNR has at present had little effect on establishment of exotic weeds. Resilience of leverage flora, floristic diversity and species origins of CHNNR are discussed in relation to its connectivity with the Melanesian region due to the South Equatorial Current operating in the region. Colubrina asiatica was recorded as a new record for oceanic islands in Australian territories. Previously recorded Ximenia americana and Digitaria ctenantha are considered locally extinct. Pattern analyses indicate that cays of similar size and vegetation structure are the most similar in floristic composition. Willis Island flora is relatively dissimilar to the CHNNR cays, due to the influence of anthropogenic activities associated with a staffed weather station

Theory of magnetism with temporal disorder applied to magnetically doped ZnO

A dynamic model of the asymmetric Ising glass is presented: an Ising model with antiferromagnet bonds with probabilities q arranged at random in a ferromagnetic matrix. The dynamics is introduced by changing the arrangement of the antiferromagnetic bonds after n Monte Carlo steps but keeping the same value of q and spin configuration. In the region where there is a second order transition between the ferromagnetic and paramagnetic states the dynamic behaviour follows that expected for motional narrowing and reverts to the static behaviour only for large n. There is a different dynamic behaviour where there is a first order transition between the ferromagnetic and spin glass states where it shows no effects of motional narrowing. The implications of this are discussed. This model is devised to explain the properties of doped ZnO where the magnetisation is reduced when the exchange interactions change with time.Comment: Paper was presented at MMM 2008 and is accepted for publication in J.A.

Evaluating content generators

Evaluating your content generator is a very important task, but difficult to do well. Creating a game content generator in general is much easier than creating a good game content generator—but what is a “good” content generator? That depends very much on what you are trying to create and why. This chapter discusses the importance and the challenges of evaluating content generators, and more generally understanding a generator’s strengths and weaknesses and suitability for your goals. In particular, we discuss two different approaches to evaluating content generators: visualizing the expressive range of generators, and using questionnaires to understand the impact of your generator on the player. These methods could broadly be called top-down and bottom-up methods for evaluating generators.peer-reviewe

Shotgun Mitogenomics Provides a Reference Phylogenetic Framework and Timescale for Living Xenarthrans

Xenarthra (armadillos, sloths, and anteaters) constitutes one of the four major clades of placental mammals. Despite their phylogenetic distinctiveness in mammals, a reference phylogeny is still lacking for the 31 described species. Here we used Illumina shotgun sequencing to assemble 33 new complete mitochondrial genomes, establishing Xenarthra as the first major placental clade to be fully sequenced at the species level for mitogenomes. The resulting data set allowed the reconstruction of a robust phylogenetic framework and timescale that are consistent with previous studies conducted at the genus level using nuclear genes. Incorporating the full species diversity of extant xenarthrans points to a number of inconsistencies in xenarthran systematics and species definition. We propose to split armadillos in two distinct families Dasypodidae (dasypodines) and Chlamyphoridae (euphractines, chlamyphorines, and tolypeutines) to better reflect their ancient divergence, estimated around 42 million years ago. Species delimitation within long-nosed armadillos (genus Dasypus) appeared more complex than anticipated, with the discovery of a divergent lineage in French Guiana. Diversification analyses showed Xenarthra to be an ancient clade with a constant diversification rate through time with a species turnover driven by high but constant extinction. We also detected a significant negative correlation between speciation rate and past temperature fluctuations with an increase in speciation rate corresponding to the general cooling observed during the last 15 million years. Biogeographic reconstructions identified the tropical rainforest biome of Amazonia and the Guianan shield as the cradle of xenarthran evolutionary history with subsequent dispersions into more open and dry habitats.Fil: Gibb, Gillian C.. Universite de Montpellier; Francia. Massey Universit; Nueva ZelandaFil: Condamine, Fabien L.. University of Gothenburg; Suecia. Universite de Montpellier; Francia. University of Alberta; CanadáFil: Kuch, Melanie. McMaster University; CanadáFil: Enk, Jacob. McMaster University; CanadáFil: Moraes Barros, Nadia. Universidade Do Porto; Portugal. Universidade de Sao Paulo; BrasilFil: Superina, Mariella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Poinar, Hendrik N.. McMaster University; CanadáFil: Delsuc, Frederic. Universite de Montpellier; Franci

Introduction to the computational structural mechanics testbed

The Computational Structural Mechanics (CSM) testbed software system based on the SPAR finite element code and the NICE system is described. This software is denoted NICE/SPAR. NICE was developed at Lockheed Palo Alto Research Laboratory and contains data management utilities, a command language interpreter, and a command language definition for integrating engineering computational modules. SPAR is a system of programs used for finite element structural analysis developed for NASA by Lockheed and Engineering Information Systems, Inc. It includes many complementary structural analysis, thermal analysis, utility functions which communicate through a common database. The work on NICE/SPAR was motivated by requirements for a highly modular and flexible structural analysis system to use as a tool in carrying out research in computational methods and exploring computer hardware. Analysis examples are presented which demonstrate the benefits gained from a combination of the NICE command language with a SPAR computational modules

Corticotropin-releasing factor receptor 1 activation during exposure to novelty stress protects against alzheimer's disease-like cognitive decline in AβPP/PS1 Mice

A lifestyle rich in physical and mental activities protects against Alzheimer's disease (AD) but the underlying mechanisms are unclear. We have proposed that this is mediated by a stress response and have shown that repeated exposure to novelty stress, which induces physical and exploratory activities, delays the progression of AD-like pathology in the TASTPM mouse model. Here, we aimed to establish the role played by corticotrophin-releasing factor receptor 1 (CRFR1), a major component of the stress axis, in TASTPM's behavioral and neuroendocrine responses to novelty and related protective effects. We show that the stress response of TASTPM mice is altered with reduced CRFR1-mediated neuroendocrine and behavioral responses to novelty and a distinct profile of behavioral responses. Repeated novelty-induced CRFR1 activation, however, mediated the improved contextual fear memory and extinction performance of TASTPM mice and increased hippocampal and fronto-cortical levels of synaptophysin, a marker of synaptic density, and fronto-cortical levels of the post-synaptic marker PSD95. The N-methyl-D-aspartate receptor (NMDAR) is the major receptor for synaptic plasticity underlying learning and memory. Although novelty-induced NMDAR activation contributed to enhancement of fear memory and synaptophysin levels, antagonism of CRFR1 and NMDAR prevented the novelty-induced increase in hippocampal synaptophysin levels but reversed the other effects of CRFR1 inactivation, i.e., the enhancement of contextual fear extinction and fronto-cortical synaptophysin and PSD95 levels. These findings suggest a novel mechanism whereby a stimulating environment can delay AD symptoms through CRFR1 activation, facilitating NMDAR-mediated synaptic plasticity and synaptogenesis in a region-dependent manner, either directly, or indirectly, by modulating PSD95. © 2013 - IOS Press and the authors. All rights reserved