3,323 research outputs found

    Spectral pitch distance and microtonal melodies

    Get PDF
    We present an experiment designed to test the effectiveness of spectral pitch distance at modeling the degree of “affinity” or “fit” of pairs of successively played tones or chords (spectral pitch distance is the cosine distance between salience-weighted, Gaussian-smoothed, pitch domain embeddings of spectral pitches—typically the first eight to ten partials of a tone). The results of a previously conducted experiment, which collected ratings of the perceived similarity and fit of root-position major and minor triads, suggest the model works well for pairs of triads in standard 12-tone equal temperament tunings. The new experiment has been designed to test the effectiveness of spectral pitch distance at modeling the affinity of tones in microtonal melodies where the partials of the tones can be variably tempered between being perfectly harmonic and perfectly matched to the underlying microtonal tuning. The use of microtonal tunings helps to disambiguate innate perceptual (psychoacoustical) responses from learned (cultural) responses. Participants are presented with a software synthesizer containing two unlabeled controls: one adjusts the precise tuning of the tones; the other adjusts the extent to which the spectrum is tempered to match the tuning (as set by the first control). A selection of microtonal melodies are played in different tunings, and the participants adjust one, or both, controls until they find a “sweet spot” at which the music sounds most “in-tune” and the notes best “fit” together. The results of these experiments will be presented and discussed

    Gated metabolic myocardial imaging, a surrogate for dual perfusion-metabolism imaging by positron emission tomography

    Get PDF
    Acknowledgments The authors are grateful for the help from Dr H Ali and Dr A Dawson. Funding: This study was performed using a research grant from the Aberdeen Royal Hospitals Trust's Endowment Fund, with further support from the Department of Medical Physics at the University of Aberdeen, for which the authors express their gratitude.Peer reviewedPublisher PD

    A dialectical approach to theoretical integration in developmental-contextual identity research

    Get PDF
    Future advances in identity research will depend on integration across major theoretical traditions. Developmental-contextualism has established essential criteria to guide this effort, including specifying the context of identity development, its timing over the life course, and its content. This article assesses four major traditions of identity research - identify status, eudaimonic identity, sociocultural theory, and narrative identity - in light of these criteria, and describes the contribution of each tradition to the broader enterprise of developmental-contextual research. This article proposes dialectical integration of the four traditions, for the purpose of generating new questions when the tensions and contradictions among theoretical traditions are acknowledged. We provide examples from existing literature of the kinds of research that could address these questions and consider ways of addressing the validity issues involved in developmental-contextual identity research

    Women and wages: Gender and the control of income in farm and Bantustan households

    Get PDF
    African Studies Seminar series. Paper presented 15 September 1986Virtually all of the married men to whom we spoke in Matatiele and Qwaqwa were bitterly opposed to their wives engaging in certain kinds of local income-generating activity. The main target of male opprobrium was shebeening, because husbands who were migrant workers were afraid that if their wives sold liquor from their homes they would be tempted into prostitution by their clients. The men were not, of course, opposed to the existence of shebeens, and were happy, when home on leave, to visit shebeens run by other men's wives, mothers or daughters. Male migrants attempted, despite their long absences from home, to exert control over their wives' activities in this regard. They left strict instructions concerning the disbursal of remittances, often threatening physical violence if their wives 'wasted' the money they remitted on liquor or the ingredients of homebrew. Where possible they also asked other men to check that their wives were not shebeening surreptitiously, and to report any breach of their prohibition. Women found it necessary to view shebeening differently. To them, it was one of the most accessible and convenient ways in which to generate a cash income from the home. It required little by way of equipment, did not demand regular inputs of time and labour, and could be undertaken at the same time as other domestic work. Women also had more personal discretion over income from shebeening than from remittances. For these reasons many women brewed and sold liquor, and some went to considerable lengths to conceal their activity from their husbands. A common strategy was to run the shebeen from the home of a friend in the vicinity - often the latter was a widow, whose marital status and age permitted her to avoid or disregard male censure. Women who did this explained that if questioned by their husbands, they could always say that they were just 'helping out' now and again for a neighbour. In both Matatiele and Qwaqwa, male and female images of shebeens were very different. Women stressed that most of the shebeens in their neighbourhood were small-scale affairs, with a limited number of clients at any one time; during the week, moreover, most of the clients were old men - pensioners for whom a visit to a shebeen in a neighbour’s house was a means of quiet recreation. Men, on the other hand, painted lurid pictures to express anxiety about their homes being turned into sites of drunken revelry in their absence, with sex and drugs as well as liquor for sale on demand. Both types of shebeen undoubtedly existed in both areas, but whereas male images seemed to represent the kind they most liked to visit themselves, women's accounts were more accurate in the case of the majority of such establishments. Disagreement about the nature of shebeens and the desirability of shebeening were part of a much broader struggle between men and women about access to income and control over this and other resources within households. This paper examines some aspects of this wider domestic struggle in the particular circumstances of the bantustans, and explores several key differences between Matatiele and Qwaqwa in this regard. The notion of 'domestic Struggle’ (Bozzoli, 1983: 144-148) is, for two reasons, central to our argument…

    Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris)

    Get PDF
    This work was funded jointly by the Biotechnology and Biological Sciences Research Council, the Department for Environment, Food and Rural Affairs, the Natural Environment Research Council, the Scottish Government, and The Wellcome Trust, under the Insect Pollinators Initiative (United Kingdom) Grant BB/ 1000313/1 (to C.N.C.).The global decline in the abundance and diversity of insect pollinators could result from habitat loss, disease, and pesticide exposure. The contribution of the neonicotinoid insecticides (e.g., clothianidin and imidacloprid) to this decline is controversial, and key to understanding their risk is whether the astonishingly low levels found in the nectar and pollen of plants is sufficient to deliver neuroactive levels to their site of action: the bee brain. Here we show that bumblebees (Bombusterrestris audax) fed field levels [10 nM, 2.1 ppb (w/w)] of neonicotinoid accumulate between 4 and 10 nM in their brains within 3 days. Acute (minutes) exposure of cultured neurons to 10 nM clothianidin, but not imidacloprid, causes a nicotinic acetylcholine receptor-dependent rapid mitochondrial depolarization. However, a chronic (2 days) exposure to 1 nM imidacloprid leads to a receptor-dependent increased sensitivity to a normally innocuous level of acetylcholine, which now also causes rapid mitochondrial depolarization in neurons. Finally, colonies exposed to this level of imidacloprid show deficits in colony growth and nest condition compared with untreated colonies. These findings provide a mechanistic explanation for the poor navigation and foraging observed in neonicotinoid treated bumblebee colonies.Publisher PDFPeer reviewe

    Hex Player—a virtual musical controller

    Get PDF
    In this paper, we describe a playable musical interface for tablets and multi-touch tables. The interface is a generalized keyboard, inspired by the Thummer, and consists of an array of virtual buttons. On a generalized keyboard, any given interval always has the same shape (and therefore fingering); furthermore, the fingering is consistent over a broad range of tunings. Compared to a physical generalized keyboard, a virtual version has some advantages—notably, that the spatial location of the buttons can be transformed by shears and rotations, and their colouring can be changed to reflect their musical function in different scales. We exploit these flexibilities to facilitate the playing not just of conventional Western scales but also a wide variety of microtonal generalized diatonic scales known as moment of symmetry, or well-formed, scales. A user can choose such a scale, and the buttons are automatically arranged so their spatial height corresponds to their pitch, and buttons an octave apart are always vertically above each other. Furthermore, the most numerous scale steps run along rows, while buttons within the scale are light-coloured, and those outside are dark or removed. These features can aid beginners; for example, the chosen scale might be the diatonic, in which case the piano’s familiar white and black colouring of the seven diatonic and five chromatic notes is used, but only one scale fingering need ever be learned (unlike a piano where every key needs a different fingering). Alternatively, it can assist advanced composers and musicians seeking to explore the universe of unfamiliar microtonal scales

    Investigating the impact of occupant response time on computer simulations of the WTC North Tower evacuation

    Get PDF
    This work explores the impact of response time distributions on high-rise building evacuation. The analysis utilises response times extracted from printed accounts and interviews of evacuees from the WTC North Tower evacuation of 11 September 2001. Evacuation simulations produced using these “real” response time distributions are compared with simulations produced using instant and engineering response time distributions. Results suggest that while typical engineering approximations to the response time distribution may produce reasonable evacuation times for up to 90% of the building population, using this approach may underestimate total evacuation times by as much as 61%. These observations are applicable to situations involving large high-rise buildings in which travel times are generally expected to be greater than response time
    corecore