Review of the financial and medicolegal implications of nasal fractures seen at St Luke’s Hospital

Simple nasal bone fractures are the third most common type of all fractures leading to numerous patient visits at the Accident & Emergency department. Nasal fractures are commonly over-investigated in St Luke’s hospital leading to a substantial financial burden on our health system. In this article we review the frequency of simple nasal fractures as well as the necessity or otherwise of nasal x-ray imaging in addition to the financial and health consequences that result from nasal x-ray imaging. These issues are also discussed from a legal perspective.peer-reviewe

CFD Modelling of Micromixing in a T-mixer with Square Bends

International audienceCFD simulations are performed to study the micro-mixing in a T-mixer with square bends by using the Villermaux-Dushman reaction. The calculated segregation indices are compared with previously published data and it is shown that whilst the trend is capture the simulation overpredict the extent of miccromixing. This paper provides guidance on the computational requirements needed to obtain accurate results in such laminar flows and shows the complex species fields that develop within the reactor

Characterization of micromixing in a Continuous Oscillatory Baffled Reactor

International audienceMicromixing is the limiting step in the progress of fast reactions and fast crystallization processes. Micromixing performance of a Nitech© glass COBR has been characterized using the competing parallel iodide-iodate test reactions. Macromixing length was also qualitatively determined by visualization of a tracer. The results show that an increase in the amplitude to baffle space ratio and a decrease of oscillation frequency improves mixing performance

Gene structure of the human metabotropic glutamate receptor 5 and functional analysis of its multiple promoters in neuroblastoma and astroglioma cells

The metabotropic glutamate receptor 5 (mGluR5) has a discrete tissue expression mainly limited to neural cells. Expression of mGluR5 is developmentally regulated and undergoes dramatic changes in association with neuropathological disorders. We report the complete genomic structure of the mGluR5 gene, which is composed of 11 exons and encompasses ∼563 kbp. Three clusters of multiple transcription initiation sites located on three distinct exons (IA, IB, and II), which undergo alternative splicing, have been identified. The 5′-flanking regions of these exons were isolated and, using a luciferase reporter gene assay, shown to possess active promoter elements in SKN-MC neuroblastoma and U178-MG astroglioma cells. Promoter IA was characterized by a CpG island; promoter IB contained a TATA box, and promoter II possessed three active Oct-1-binding sites. Preferential luciferase activity was observed in SKN-MC concomitant with differential DNA binding activity to several responsive elements, including CREB, Oct-1, C/EBP, and Brn-2. Exposure to growth factors produced enhanced expression of promoters IB and II in astroglioma cells and activation of NF-κB. These results suggest that alternative 5′-splicing and usage of multiple promoters may contribute regulatory mechanisms for tissue- and context-specific expression of the mGluR5 gene

Optomechanics for quantum technologies

The ability to control the motion of mechanical systems through interaction with light has opened the door to a plethora of applications in fundamental and applied physics. With experiments routinely reaching the quantum regime, the focus has now turned towards creating and exploiting interesting non-classical states of motion and entanglement in optomechanical systems. Quantumness has also shifted from being the very reason why experiments are constructed to becoming a resource for the investigation of fundamental physics and the creation of quantum technologies. Here, by focusing on opto- and electromechanical platforms we review recent progress in quantum state preparation and entanglement of mechanical systems, together with applications to signal processing and transduction, quantum sensing and topological physics, as well as small-scale thermodynamics

Effect of Axial Agitator Configuration (Up-Pumping, Down-Pumping, Reverse Rotation) on Flow Patterns Generated in Stirred Vessels

Single phase turbulent flow in a tank stirred with two different axial impellers - a pitched blade turbine (PBT) and a Mixel TT (MTT)- has been studied using Laser Doppler Velocimetry. The effect of the agitator configuration, i.e. up-pumping, down-pumping and reverse rotation, on the turbulent flow field, as well as power, circulation and pumping numbers has been investigated. An agitation index for each configuration was also determined. In the down-pumping mode, the impellers induced one circulation loop and the upper part of the tank was poorly mixed. When up-pumping, two circulation loops are formed, the second in the upper vessel. The PBT pumping upwards was observed to have a lower flow number and to consume more power than when down-pumping, however the agitation index and circulation efficiencies were notably higher. The MTT has been shown to circulate liquid more efficiently in the up-pumping configuration than in the other two modes. Only small effects of the MTT configuration on the power number, flow number and pumping effectiveness have been observed

Design of micromixers using CFD modelling

The effect of various geometrical parameters of a grooved staggered herringbone micromixer on the mixing performance has been investigated using Computational Fluid Dynamics. Mixing quality has been quantified with spatial data statistics, maximum striation thickness and residence time analyses. The results show that the number of grooves per mixing cycle does not affect the mixing quality in an important way. On the other hand, a larger groove depth and width allow the maximum striation thickness to be rapidly reduced, without increasing the pressure drop across the mixer. Wide grooves, however, create significant dead zones in the microchannel, whereas deep grooves improve the spatial mixing quality

Impact of thixotropy on flow patterns induced in a stirred tank : numerical and experimental studies

Agitation of a thixotropic shear-thinning fluid exhibiting a yield stress is investigated both experimentally and via simulations. Steady-state experiments are conducted at three impeller rotation rates (1, 2 and 8 s−1) for a tank stirred with an axial-impeller and flow-field measurements are made using particle image velocimetry (PIV) measurements. Threedimensional numerical simulations are also performed using the commercial CFD code ANSYS CFX10.0. The viscosity of the suspension is determined experimentally and is modelled using two shear-dependant laws, one of which takes into account the flow instabilities of such fluids at low shear rates. At the highest impeller speed, the flow exhibits the familiar outward pumping action associated with axial-flow impellers. However, as the impeller speed decreases, a cavern is formed around the impeller, the flow generated in the vicinity of the agitator reorganizes and its pumping capacity vanishes. An unusual flow pattern, where the radial velocity dominates, is observed experimentally at the lowest stirring speed. It is found to result from wall slip effects. Using blades with rough surfaces prevents this peculiar behaviour and mainly resolves the discrepancies between the experimental and computational results

Pyogenic granuloma as a surrogate indicator of deep seated foreign bodies: A case report

Although pyogenic granulomas are often clinically associated with foreign bodies or recurrent traumatic injury, this association is not well documented. We report a case of a recurrent, intractable pyogenic granuloma due to a missed foreign body. An extensive search retrieved no previous literature reporting this association. This lack of evidence bases may hinder the hand surgeon from extending the wound incision and thorough exploration. Recurrent pyogenic granulomas should lead the hand surgeon to entertain the possibility of a missed foreign body

MIXING AND RECIRCULATION CHARACTERISTICS OF GAS- LIQUID TAYLOR FLOW IN MICROREACTORS

Abstract. The effects of operating parameters (capillary and Reynolds numbers) and microchannel aspect ratio (= w/h = [1, 2.5, 4]) on the recirculation characteristics of the liquid slug in gas-liquid Taylor flow in microchannels has been investigated using 3-dimensional Volume Of Fluid numerical simulations. The results show good agreement with previous results in circular and square geometrie