Control of convection by dfferent buoyancy forces

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.Thermal convection in vertical concentric cylinders under the influence of di erent buoyancy force fields is the focus of the experimental project ’CiC’(Convection in Cylinders). The objectives are to investigate thermal convective flow in natural gravity with axial buoyancy and in micro-gravity environment of a parabolic flight with radial buoyancy, and additionally also the superposition of both buoyancy force fields. The radial buoyancy is forced by the dielectrophoretic effect due to applying a high-voltage potential Vapp between the two cylinders. The experiment contains two separately fully automated experiment cells, which differ only in their radius ratio η = b/a. The convective flow is observed with tracer particles and laser light sheet illumination. For the case of natural convection, there exists a stable single convective cell over the whole Rayleigh number domain with Ra ~ ΔT with increasing the temperature difference between the inner and outer cylindrical boundaries. For the case of a pure dielectrophoretic driven convection in micro-gravity environment, stratification effects are described with RaE ~ Vapp with increasing the high voltage potential. The superposition of both buoyancy forces indicates the disturbance of the single convective cell and therewith the onset of instabilities at very low Ra for the smaller η. The presented results demonstrate that the dielectrophoretic effect can be used for flow control and enhancement of heat transfer applications in space as well as on Earth.The “Convection in Cylinders (CiC)” project is funded by the German Aerospace Center DLR within the “GeoFlow” project (grant no. 50 WM 0122 and 50 WM 0822). The authors would also like to thank ESA (grant no. AO-99-049) for funding “GeoFlow” and the “GeoFlow” Topical Team (grant no. 18950/05/NL/VJ)

Update on the ICUD-SIU consultation on multi-parametric magnetic resonance imaging in localised prostate cancer

Introduction: Prostate cancer (PCa) imaging is a rapidly evolving field. Dramatic improvements in prostate MRI during the last decade will probably change the accuracy of diagnosis. This chapter reviews recent current evidence about MRI diagnostic performance and impact on PCa management. Materials and methods: The International Consultation on Urological Diseases nominated a committee to review the literature on prostate MRI. A search of the PubMed database was conducted to identify articles focussed on MP-MRI detection and staging protocols, reporting and scoring systems, the role of MP-MRI in diagnosing PCa prior to biopsy, in active surveillance, in focal therapy and in detecting local recurrence after treatment. Results: Differences in opinion were reported in the use of the strength of magnets [1.5 Tesla (T) vs. 3T] and coils. More agreement was found regarding the choice of pulse sequences; diffusion-weighted MRI (DW-MRI), dynamic contrast-enhanced MRI (DCE MRI), and/or MR spectroscopy imaging (MRSI) are recommended in addition to conventional T2-weighted anatomical sequences. In 2015, the Prostate Imaging Reporting and Data System (PI-RADS version 2) was described to standardize image acquisition and interpretation. MP-MRI improves detection of clinically significant PCa (csPCa) in the repeat biopsy setting or before the confirmatory biopsy in patients considering active surveillance. It is useful to guide focal treatment and to detect local recurrences after treatment. Its role in biopsy-naive patients or during the course of active surveillance remains debated. Conclusion: MP-MRI is increasingly used to improve detection of csPCa and for the selection of a suitable therapeutic approach

Sheet-like and plume-like thermal flow in a spherical convection experiment performed under microgravity

We introduce, in spherical geometry, experiments on electro-hydrodynamic driven Rayleigh-Bénard convection that have been performed for both temperature-independent (‘GeoFlow I') and temperature-dependent fluid viscosity properties (‘GeoFlow II') with a measured viscosity contrast up to 1.5. To set up a self-gravitating force field, we use a high-voltage potential between the inner and outer boundaries and a dielectric insulating liquid; the experiments were performed under microgravity conditions on the International Space Station. We further run numerical simulations in three-dimensional spherical geometry to reproduce the results obtained in the ‘GeoFlow' experiments. We use Wollaston prism shearing interferometry for flow visualization - an optical method producing fringe pattern images. The flow patterns differ between our two experiments. In ‘GeoFlow I', we see a sheet-like thermal flow. In this case convection patterns have been successfully reproduced by three-dimensional numerical simulations using two different and independently developed codes. In contrast, in ‘GeoFlow II', we obtain plume-like structures. Interestingly, numerical simulations do not yield this type of solution for the low viscosity contrast realized in the experiment. However, using a viscosity contrast of two orders of magnitude or higher, we can reproduce the patterns obtained in the ‘GeoFlow II' experiment, from which we conclude that nonlinear effects shift the effective viscosity rati

The role of magnetic resonance imaging (MRI) in focal therapy for prostate cancer: recommendations from a consensus panel

OBJECTIVE: To establish a consensus on the utility of multiparametric magnetic resonance imaging (mpMRI) to identify patients for focal therapy. METHODS: Urological surgeons, radiologists, and basic researchers, from Europe and North America participated in a consensus meeting about the use of mpMRI in focal therapy of prostate cancer. The consensus process was face-to-face and specific clinical issues were raised and discussed with agreement sought when possible. All participants are listed among the authors. Topics specifically did not include staging of prostate cancer, but rather identifying the optimal requirements for performing MRI, and the current status of optimally performed mpMRI to (i) determine focality of prostate cancer (e.g. localising small target lesions of \u3e/=0.5 mL), (ii) to monitor and assess the outcome of focal ablation therapies, and (iii) to identify the diagnostic advantages of new MRI methods. In addition, the need for transperineal template saturation biopsies in selecting patients for focal therapy was discussed, if a high quality mpMRI is available. In other words, can mpMRI replace the role of transperineal saturation biopsies in patient selection for focal therapy? RESULTS: Consensus was reached on most key aspects of the meeting; however, on definition of the optimal requirements for mpMRI, there was one dissenting voice. mpMRI is the optimum approach to achieve the objectives needed for focal therapy, if made on a high quality machine (3T with/without endorectal coil or 1.5T with endorectal coil) and judged by an experienced radiologist. Structured and standardised reporting of prostate MRI is paramount. State of the art mpMRI is capable of localising small tumours for focal therapy. State of the art mpMRI is the technique of choice for follow-up of focal ablation. CONCLUSIONS: The present evidence for MRI in focal therapy is limited. mpMRI is not accurate enough to consistently grade tumour aggressiveness. Template-guided saturation biopsies are no longer necessary when a high quality state of the art mpMRI is available; however, suspicious lesions should always be confirmed by (targeted) biopsy

GeoFlow: European Microgravity Experiments on Thermal Convection in Rotating Spherical Shells under influence of Central Force Field

Abstract We report on the status of preparatory work in the GeoFlow Experiment which will take place on board Columbus Orbital Facility (COF) at the International Space Station (ISS). GeoFlow focus on investigations of the stability and dynamics of convective spherical gap flows under influence of a central force field. To exclude the unidirectional gravitational force which acts on earth's surface the planed long-time measurements have to take place in microgravity environment. After a introduction and an overview of experiment hardware preparation status which includes application of measurement techniques, preparatory 3D numerical flow simulations as well as experimental work and the way of experiment data analysis are presented. Also some aspects of the experiment operation phase will be given. The paper is then closed with concluding remarks and an outlook on possible future GeoFlow reflight campaigns

Haus House

Preliminary design work for the Solar Decathlon 2014 entry Techstyle Haus completed in a wintersession 2013 RISD design studio in Erfurt, Germany taught by Jonathan Knowles. The Solar Decathlon competition challenges twenty collegiate teams to design and build sustainable homes that are powered exclusively by solar energy and incorporate sustainable architecture and design. Techstyle Haus is an international Brown University, RISD and University of Applied Sciences Erfurt,Germany collaboration designing a solar passivehaus out of high performance textiles

Techstyle Haus

Preliminary design work for the Solar Decathlon 2014 entry Techstyle Haus completed in a wintersession 2013 RISD design studio in Erfurt, Germany taught by Jonathan Knowles. The Solar Decathlon competition challenges twenty collegiate teams to design and build sustainable homes that are powered exclusively by solar energy and incorporate sustainable architecture and design. Techstyle Haus is an international Brown University, RISD and University of Applied Sciences Erfurt,Germany collaboration designing a solar passivehaus out of high performance textiles

Additecture

Preliminary design work for the Solar Decathlon 2014 entry Techstyle Haus completed in a wintersession 2013 RISD design studio in Erfurt, Germany taught by Jonathan Knowles. The Solar Decathlon competition challenges twenty collegiate teams to design and build sustainable homes that are powered exclusively by solar energy and incorporate sustainable architecture and design. Techstyle Haus is an international Brown University, RISD and University of Applied Sciences Erfurt,Germany collaboration designing a solar passivehaus out of high performance textiles

Whole exome sequencing identifies genetic variants in inherited thrombocytopenia with secondary qualitative function defects

Inherited thrombocytopenias are a heterogeneous group of disorders characterised by abnormally low platelet counts which can be associated with abnormal bleeding. Next generation sequencing has previously been employed in these disorders for the confirmation of suspected genetic abnormalities, and more recently in the discovery of novel disease causing genes. However its full potential has not previously been utilised. Over the past 6 years we have sequenced the exomes from 55 patients, including 37 index cases and 18 additional family members, all of whom were recruited to the UK Genotyping and Phenotyping of Platelets study. All patients had inherited or sustained thrombocytopenia of unknown aetiology with platelet counts varying from 11-186x109 /L. Of the 51 patients phenotypically tested, 37 (73%), had an additional secondary qualitative platelet defect. Using whole exome sequencing analysis we have identified “pathogenic” or “likely pathogenic” variants in 46% (17/37) of our index patients with thrombocytopenia. In addition, we report variants of uncertain significance in 12 index cases which include novel candidate genetic variants in previously unreported genes in four index cases. These results demonstrate that whole exome sequencing is an efficient method for elucidating potential pathogenic genetic variants in inherited thrombocytopenia. Whole exome sequencing also has the added benefit of discovering potentially pathogenic genetic variants for further study in novel genes not previously implicated in inherited thrombocytopenia