3,323 research outputs found
Spectral pitch distance and microtonal melodies
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
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Metrics for pitch collections
Models of the perceived distance between pairs of pitch collections are a core component of broader models of the perception of tonality as a whole. Numerous different distance measures have been proposed, including voice-leading, psychoacoustic, and pitch and interval class distances; but, so far, there has been no attempt to bind these different measures into a single mathematical framework, nor to incorporate the uncertain or probabilistic nature of pitch perception (whereby tones with similar frequencies may, or may not, be heard as having the same pitch).
To achieve these aims, we embed pitch collections in novel multi-way expectation arrays, and show how metrics between such arrays can model the perceived dissimilarity of the pitch collections they embed. By modeling the uncertainties of human pitch perception, expectation arrays indicate the expected number of tones, ordered pairs of tones, ordered triples of tones and so forth, that are heard as having any given pitch, dyad of pitches, triad of pitches, and so forth. The pitches can be either absolute or relative (in which case the arrays are invariant with respect to transposition).
We provide a number of examples that show how the metrics accord well with musical intuition, and suggest some ways in which this work may be developed
Gated metabolic myocardial imaging, a surrogate for dual perfusion-metabolism imaging by positron emission tomography
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
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
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…
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Prenatal anxiety, maternal stroking in infancy, and symptoms of emotional and behavioral disorders at 3.5 years
Animal findings of long-term effects of maternal behaviors mediated via altered GR gene expression will, if translated into humans, have far reaching implications for our understanding of child and adolescent psychopathology. We have previously shown that mothers' self-reported stroking of their infants modifies associations between prenatal depression and anxiety and child outcomes at 29 weeks and 2.5 years. Here, we examine whether the effect of early maternal stroking is evident at 3.5 years, and in a much larger sample than in previous publications. A general population sample of 1233 first-time mothers completed anxiety measures at 20 weeks gestation, 865 reported on infant stroking at 9 weeks, and 813 on child symptoms at 3.5 years. Maternal stroking moderated the association between pregnancy-specific anxiety and internalizing (p = 0.010) and externalizing (p = 0.004) scores, such that an effect of PSA to increase symptoms was markedly reduced for mothers who reported high levels of stroking. There was no effect of maternal stroking on general anxiety. The findings confirm the previously reported effect of maternal stroking, and in a much larger sample. They indicate that there are long-term effects of early maternal stroking, modifying associations between prenatal anxiety and child emotional and behavioral symptoms
Chronic exposure to neonicotinoids increases neuronal vulnerability to mitochondrial dysfunction in the bumblebee (Bombus terrestris)
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
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
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
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How does perinatal maternal mental health explain early social inequalities in child behavioural and emotional problems? Findings from the Wirral Child Health and Development Study
This study aimed to assess how maternal mental health mediates the association between childhood socio-economic conditions at birth and subsequent child behavioural and emotional problem scores. Analysis of the Wirral Child Health and Development Study (WCHADS), a prospective epidemiological longitudinal study of the early origins of child mental health (n = 664). Household income at 20-weeks gestation, a measure of socio-economic conditions (SECs) in pregnancy, was the main exposure. The outcome measure was externalising and internalising problems, as measured by the Child Behaviour Checklist at 5 years. We assessed the association of household income with child behavioural outcomes in sequential linear models adjusting for maternal mental health in the pre- and post- natal period. Children of mothers in more disadvantaged households had higher scores for externalising behaviour with a difference of 3.6 points comparing the most affluent to the most disadvantaged families (the socio-economic (SEC) gap). In our regression model adjusting for baseline confounders, comparing children of mothers in the most disadvantaged households to the least disadvantaged, we found that most disadvantaged children scored 45 percentage points (95% CI 9, 93) higher for externalising problems, and 42% of this difference was explained in the fully adjusted model. Adjusting for prenatal maternal depressive symptomology attenuated the SEC gap in externalising problems by about a third, rendering the association non-significant, whilst adjusting for pre- and post-natal maternal mental health attenuated the SEC gap by 42%. There was no significant relationship between household income and internalising problems. Social disadvantage is associated with higher child externalising behaviour problems score at age 5, and about 40% of this was explained by maternal perinatal mental health. Policies supporting maternal mental health in pregnancy are important to address the early emergence of inequalities in child mental health
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