How was it for you? A cross-disciplinary study of ‘troublesome knowledge’ as identified by undergraduate students and lecturers in Geography, Medical Science and Psychology

We carried out a small scale pilot study to determine whether participants would spontaneously identify Threshold Concepts (TC’s) and/or troublesome knowledge during open questioning on the characteristics of their disciplines. Students and lecturers reflected upon both easy and difficult aspects of their studies or teaching practice in either group discussions or one-to-one interviews. We compared students and staff observations both within and between the disciplines we examined (Geography, Medical Sciences and Psychology undergraduate degrees). Our intention was to provide specific examples of TC’s within our three disciplines to inform further discussion of embedding the enhancement theme both in our practice and in the learning experiences of our students. Our working hypothesis was that if TC’s exerted an influence on the teaching and learning experience either negatively or otherwise, then we would find ample evidence supplied in our interviews. What we found was that overwhelmingly our interviewees focussed on generic skills-based aspects of teaching and learning. Only three potential content-specific TC’s were offered spontaneously by students and these were all from the discipline of geography

Prediction of pressure drop in multiphase horizontal pipe flow

Empirical correlations were tested against reliable two phase pipe flow data for the prediction of pressure drop. Correlations are recommended for the prediction with stratified and annular type flows. When these correlations were adapted to three phase gaswater-oil pipe flow in general they predicted for intermittent slug type flows. Momentum balance models could not be successfully adapted to the prediction of pipe three phase pressure drop

Two- and Three-Phase Flow Through a 90 Degree Bend

Data are presented for two-phase air/water pipeflow and three-phase air/oil/water in a 0.026 m i.d. pipe and elbow bend (R/d = 0.654) for vertical to horizontal flow. The two-phase results were shown to be dependant on the flow regimes present in the system. The elbow bend acted either to smooth the transition from vertical to horizontal flow when the liquid rate was below the bubble rise velocity in the inlet leg (when negative bend pressure losses were achieved), or to generate droplets and increase the bend pressure drop substantially at higher fluid rates.Three-phase data also showed significant but not such dramatic differences, depending on the combined liquid rate being above or below the bubble rise velocity in the inlet leg. Again the variation of pressure drop for the system could be qualitatively explained by the observed flow regimes.For both two-phase and three-phase systems, the observed bend pressure drop could be correlated using a Lockhart-Martinelli approach based on the single-phase flow data for the bend

Origin and significance of 'dispersed facies' basal ice: Svínafellsjökull, Iceland

Dispersed facies basal ice - massive (i.e. structureless) ice with dispersed debris aggregates - is present at the margins of many glaciers and, as a product of internal glacial processes, has the potential to provide important information about the mechanisms of glacier flow and the nature of the subglacial environment. The origin of dispersed facies is poorly understood, with several hypotheses having been advanced for its formation, and there is disagreement as to whether it is largely a sedimentary or a tectonic feature. We test these established hypotheses at the temperate glacier Svfnafellsjokull, Iceland, and find that none fully account for dispersed facies characteristics at this location. Instead, dispersed facies physical, sedimentological and stable-isotope (5180, 8D) characteristics favour a predominantly tectonic origin that we suggest comprises the regelation and straininduced metamorphism of debris-rich basal ice that has been entrained into an englacial position by tectonic processes operating at the base of an icefall. Further thickening of the resultant dispersed facies may also occur tectonically as a result of ice flow against the reverse bed slope of a terminal overdeepening. Lack of efficient subglacial drainage in the region of the overdeepening may limit basal melting and thus favour basal ice preservation, including the preservation of dispersed facies. Despite the relatively low sediment content of dispersed facies (~1.6% by volume), its thickness (up to 25 m) and ubiquity at Svfnafellsjokull results in a significant contribution to annual sediment discharge (1635-3270 m3 a"1) that is ~6.5 times that contributed by debris-rich stratified facies basal ice

Atypical features in pleomorphic adenoma--a clinicopathologic study and implications for management.

Pleomorphic adenoma is the most common salivary gland neoplasm and infrequently undergoes malignant transformation. Carcinoma ex pleomorphic adenoma is typically an infiltrative neoplasm with features of cellular pleomorphism, high mitotic activity, peri-neural and vascular invasion. More recently, sub-groups of pleomorphic adenoma have been described exhibiting vascular invasion and features of malignancy without evidence of extra-capsular extension. There is little information in the literature regarding how these different histological variants influence clinical presentation and outcome following primary treatment. Following a review of 100 consecutive pleomorphic adenomas removed from the major salivary glands, 4 cases with atypical histological features were found. Three tumours exhibited features of dysplasia/carcinoma without evidence of extra-capsular invasion and a further case demonstrated benign vascular invasion. There were no clinical features suggestive of the atypical nature of these neoplasms, though fine needle aspiration cytology (FNAC) was suspicious of a malignancy in 2 cases and CT scan in 1 case. Patients underwent a superficial parotidectomy or submandibular gland excision based on the location of the lesion. All lesions were completely excised and there were no recurrences in this series

Wake Development behind Paired Wings with Tip and Root Trailing Vortices: Consequences for Animal Flight Force Estimates

Recent experiments on flapping flight in animals have shown that a variety of unrelated species shed a wake behind left and right wings consisting of both tip and root vortices. Here we present an investigation using Particle Image Velocimetry (PIV) of the behaviour and interaction of trailing vortices shed by paired, fixed wings that simplify and mimic the wake of a flying animal with a non-lifting body. We measured flow velocities at five positions downstream of two adjacent NACA 0012 aerofoils and systematically varied aspect ratio, the gap between the wings (corresponding to the width of a non-lifting body), angle of attack, and the Reynolds number. The range of aspect ratios and Reynolds number where chosen to be relevant to natural fliers and swimmers, and insect flight in particular. We show that the wake behind the paired wings deformed as a consequence of the induced flow distribution such that the wingtip vortices convected downwards while the root vortices twist around each other. Vortex interaction and wake deformation became more pronounced further downstream of the wing, so the positioning of PIV measurement planes in experiments on flying animals has an important effect on subsequent force estimates due to rotating induced flow vectors. Wake deformation was most severe behind wings with lower aspect ratios and when the distance between the wings was small, suggesting that animals that match this description constitute high-risk groups in terms of measurement error. Our results, therefore, have significant implications for experimental design where wake measurements are used to estimate forces generated in animal flight. In particular, the downstream distance of the measurement plane should be minimised, notwithstanding the animal welfare constraints when measuring the wake behind flying animals

Landscape science: a Russian geographical tradition

The Russian geographical tradition of landscape science (landshaftovedenie) is analyzed with particular reference to its initiator, Lev Semenovich Berg (1876-1950). The differences between prevailing Russian and Western concepts of landscape in geography are discussed, and their common origins in German geographical thought in the late nineteenth and early twentieth centuries are delineated. It is argued that the principal differences are accounted for by a number of factors, of which Russia's own distinctive tradition in environmental science deriving from the work of V. V. Dokuchaev (1846-1903), the activities of certain key individuals (such as Berg and C. O. Sauer), and the very different social and political circumstances in different parts of the world appear to be the most significant. At the same time it is noted that neither in Russia nor in the West have geographers succeeded in specifying an agreed and unproblematic understanding of landscape, or more broadly in promoting a common geographical conception of human-environment relationships. In light of such uncertainties, the latter part of the article argues for closer international links between the variant landscape traditions in geography as an important contribution to the quest for sustainability

IUPHAR-DB: An Open-Access, Expert-Curated Resource for Receptor and Ion Channel Research

[Image: see text] This contribution highlights efforts by the International Union of Basic and Clinical Pharmacology (IUPHAR) Nomenclature Committee (NC-IUPHAR) to classify human receptors and ion channels, to document their properties, and to recommend ligands that are useful for characterization. This effort has inspired the creation of an online database (IUPHAR-DB), which is intended to provide free information to all scientists, summarized from primary literature by experts