Cross-modal associations in synaesthesia: vowel colours in the ear of the beholder

Human speech conveys many forms of information, but for some exceptional individuals (synaesthetes), listening to speech sounds can automatically induce visual percepts such as colours. In this experiment, grapheme–colour synaesthetes and controls were asked to assign colours, or shades of grey, to different vowel sounds. We then investigated whether the acoustic content of these vowel sounds influenced participants’ colour and grey-shade choices. We found that both colour and grey-shade associations varied systematically with vowel changes. The colour effect was significant for both participant groups, but significantly stronger and more consistent for synaesthetes. Because not all vowel sounds that we used are “translatable” into graphemes, we conclude that acoustic–phonetic influences co-exist with established graphemic influences in the cross-modal correspondences of both synaesthetes and non-synaesthetes

Tom Spurgeon and Michael Dean. We Told You So: Comics As Art. Seattle: Fantagraphics Books, 2016.

Review of Tom Spurgeon and Michael Dean. We Told You So: Comics As Art. Seattle: Fantagraphics Books, 2016

Population Ecology of the Queensnake (Regina Septemvittata) in an Urban Creek, 2008 to 2019

Habitat fragmentation is a common result of urbanization and species living in these fragments are at risk of extirpation. We conducted a 12-y (2008–2019) capture-mark-recapture study on snakes living in a 593-m section of Rock Castle Creek flowing through an urban area in central Virginia, USA. Our study site was occupied primarily by Queensnakes (Regina septemvittata). We used data from 168 individual Queensnakes to examine several aspects of their population ecology including survival rates (0.52), reproductive effort (21.3% juvenile to adult ratio), growth rates (68% and 30.6% increase for 1 to 2 y-old and 2 to 3+ y-old snakes, respectively), and sex ratio (1:1). Our population estimates, though with wide confidence intervals, showed that this population of approximately 25 adult snakes has persisted over time despite being in an urban environment. The life-history characteristics of this snake of limited movement, habitat specificity, diet specialization (eating only freshly molted crayfish, Cambarus spp.), and small body size likely reduced risks associated with nearby roads and parking lots. These same life-history characteristics, however, make Queensnakes vulnerable to extirpation should pollution cause declines in crayfish populations or otherwise make their habitat fragment inhospitable

Nonlinear Scattering of a Bose-Einstein Condensate on a Rectangular Barrier

We consider the nonlinear scattering and transmission of an atom laser, or Bose-Einstein condensate (BEC) on a finite rectangular potential barrier. The nonlinearity inherent in this problem leads to several new physical features beyond the well-known picture from single-particle quantum mechanics. We find numerical evidence for a denumerably infinite string of bifurcations in the transmission resonances as a function of nonlinearity and chemical potential, when the potential barrier is wide compared to the wavelength of oscillations in the condensate. Near the bifurcations, we observe extended regions of near-perfect resonance, in which the barrier is effectively invisible to the BEC. Unlike in the linear case, it is mainly the barrier width, not the height, that controls the transmission behavior. We show that the potential barrier can be used to create and localize a dark soliton or dark soliton train from a phonon-like standing wave.Comment: 15 pages, 15 figures, new version includes clarification of definition of transmission coefficient in general nonlinear vs. linear cas

Finding qualitative research: an evaluation of search strategies

BACKGROUND: Qualitative research makes an important contribution to our understanding of health and healthcare. However, qualitative evidence can be difficult to search for and identify, and the effectiveness of different types of search strategies is unknown. METHODS: Three search strategies for qualitative research in the example area of support for breast-feeding were evaluated using six electronic bibliographic databases. The strategies were based on using thesaurus terms, free-text terms and broad-based terms. These strategies were combined with recognised search terms for support for breast-feeding previously used in a Cochrane review. For each strategy, we evaluated the recall (potentially relevant records found) and precision (actually relevant records found). RESULTS: A total yield of 7420 potentially relevant records was retrieved by the three strategies combined. Of these, 262 were judged relevant. Using one strategy alone would miss relevant records. The broad-based strategy had the highest recall and the thesaurus strategy the highest precision. Precision was generally poor: 96% of records initially identified as potentially relevant were deemed irrelevant. Searching for qualitative research involves trade-offs between recall and precision. CONCLUSIONS: These findings confirm that strategies that attempt to maximise the number of potentially relevant records found are likely to result in a large number of false positives. The findings also suggest that a range of search terms is required to optimise searching for qualitative evidence. This underlines the problems of current methods for indexing qualitative research in bibliographic databases and indicates where improvements need to be made