Colloquium: Graphene spectroscopy

Spectroscopic studies of electronic phenomena in graphene are reviewed. A variety of methods and techniques are surveyed, from quasiparticle spectroscopies (tunneling, photoemission) to methods probing density and current response (infrared optics, Raman) to scanning probe nanoscopy and ultrafast pump-probe experiments. Vast complimentary information derived from these investigations is shown to highlight unusual properties of Dirac quasiparticles and many-body interaction effects in the physics of graphene.Comment: 36 pages, 16 figure

Guano morphology has the potential to inform conservation strategies in British bats

Bats are primary consumers of nocturnal insects, disperse nutrients across landscapes, and are excellent bioindicators of an ecosystem’s health, however four of the seventeen Great British species are listed as declining. In this study we aim to investigate the link between bat guano morphology and diet, specifically looking at the ability to predict 1) species, 2) dietary guild, and 3) bat size, using guano morphology alone. Guano from 16 bat species sampled from across Great Britain were analysed to determine various morphological metrics. These data were coupled with diet data obtained by an extensive literature review. It was found that guano morphology overlapped too much to make predictions on the species of bat which deposited the guano, however, in some cases, it could be used to indicate the dietary guild to which the bat belonged. In general, guano morphology seems more correlated to diet than species. This enables the identification of the most important prey taxa within a local environment; a crucial step for informing conservation strategies

Effects of built environment morphology on wind turbine noise exposure at building façades

© 2017 Elsevier LtdWith wind farms installed in urban and suburban areas, the noise exposure of buildings is affected both by distance attenuation and the morphology of the built environment. With the aim of exploring the noise-resisting effects of built environment morphology, three kinds of typical suburban areas in the UK were sampled and noise maps were generated based upon an idealised modern wind turbine placed at various setback distances from each site. Relationships between morphological indices and building façade exposures were examined through regression analyses. Noise reduction levels of five morphological indices were given in terms of resisting wind turbine noise with different source-receiver (S-R) distances, and at different frequencies. The results show that built environment morphology has considerable effects on resisting the noise exposure of buildings and can create a quiet façade with up to 13 dBA difference to the most exposure façade. Among the five indices, building orientation is found to be most effective in resisting the noise exposure of building façades, followed by the length and shape of the building. The noise resistance effects vary by different S-R distances and differ by frequency. Four morphological indices are found to be effective in resisting noise at low frequencies, typically at 50 Hz

Quantifying galaxy morphology

How do the different shapes of galaxies arise? Milena Pawlik describes work to identify the role of galaxy mergers and starbursts in galactic evolution.Publisher PDFPeer reviewe

morphology

We present a cladistic analysis of all the species of Smallanthus. Six taxa within Rumfordia, Ichthyothere, Acanthospermum and Tridax served as outgroups. We evaluated the monophyly and the relationships between the species of Smallanthus through a maximum parsimony study based on morphological data. The matrix included 31 qualitative characters from floral and vegetative parts of the specimens. We also explored the phylogenetic significance of treating quantitative characters as continuous. Only one most parsimonious tree was obtained. In agreement with previous phylogenetic studies based on molecular data, we recovered a monophyletic Smallanthus. The presence of ray corollas, densely pubescent at the base, was the synapomorphy that defined Smallanthus. Smallanthus microcephalus and two other major clades were recovered. The first clade included S. glabratus, S. fruticosus, S. jelskii and S. pyramidalis, while the second one contained the remaining species of Smallanthus. The analysis recovered one species of Rumfordia as sister to Smallanthus. We present a new combination, Smallanthus cocuyensis, based on morphological analysis of the type specimen