Spatiotemporal evolution of runaway electrons from synchrotron images in Alcator C-Mod

In the Alcator C-Mod tokamak, relativistic runaway electron (RE) generation can occur during the flattop current phase of low density, diverted plasma discharges. Due to the high toroidal magnetic field (B = 5.4 T), RE synchrotron radiation is measured by a wide-view camera in the visible wavelength range (~400-900 nm). In this paper, a statistical analysis of over one thousand camera images is performed to investigate the plasma conditions under which synchrotron emission is observed in C-Mod. In addition, the spatiotemporal evolution of REs during one particular discharge is explored in detail via a thorough analysis of the distortion-corrected synchrotron images. To accurately predict RE energies, the kinetic solver CODE [Landreman et al 2014 Comput. Phys. Commun. 185 847-855] is used to evolve the electron momentum-space distribution at six locations throughout the plasma: the magnetic axis and flux surfaces q = 1, 4/3, 3/2, 2, and 3. These results, along with the experimentally-measured magnetic topology and camera geometry, are input into the synthetic diagnostic SOFT [Hoppe et al 2018 Nucl. Fusion 58 026032] to simulate synchrotron emission and detection. Interesting spatial structure near the surface q = 2 is found to coincide with the onset of a locked mode and increased MHD activity. Furthermore, the RE density profile evolution is fit by comparing experimental to synthetic images, providing important insight into RE spatiotemporal dynamics

Rolle der Zytologie in der hämatopathologischen Diagnostik

Zusammenfassung: Die Zytologie stellt ein wichtiges diagnostisches Instrument in der täglichen Praxis der Hämatopathologie dar. Durch den zytologisch erfolgten Nachweis nichthämatologischer Ursachen einer Knotenbildung (z.B. Speicheldrüsenneoplasien, Tuberkulose, Melanom- oder Karzinommetastasen) besteht seltener die Notwendigkeit einer chirurgischen Exzision. Die kombinierte Anwendung morphologischer, immunphänotypischer sowie molekularer Analysen und der fachliche Austausch machen diese Untersuchungstechnik sicher. Somit stellt die zytologische Untersuchung in verschiedensten Situationen eine Alternative zur Exzisionsbiopsie dar - auch bei primären hämatologischen Erkrankungen und insbesondere bei Rezidive

Surface waves on a soft viscoelastic layer produced by an oscillating microbubble

Ultrasound-driven bubbles can cause significant deformation of soft viscoelastic layers, for instance in surface cleaning and biomedical applications. The effect of the viscoelastic properties of a boundary on the bubble-boundary interaction has been explored only qualitatively, and remains poorly understood. We investigate the dynamic deformation of a viscoelastic layer induced by the volumetric oscillations of an ultrasound-driven microbubble. High-speed video microscopy is used to observe the deformation produced by a bubble oscillating at 17-20 kHz in contact with the surface of a hydrogel. The localised oscillating pressure applied by the bubble generates surface elastic (Rayleigh) waves on the gel, characterised by elliptical particle trajectories. The tilt angle of the elliptical trajectories varies with increasing distance from the bubble. Unexpectedly, the direction of rotation of the surface elements on the elliptical trajectories shifts from prograde to retrograde at a distance from the bubble that depends on the viscoelastic properties of the gel. To explain these behaviours, we develop a simple three-dimensional model for the deformation of a viscoelastic solid by a localised oscillating force. By using as input for the model the values of the shear modulus obtained from the propagation velocity of the Rayleigh waves, we find good qualitative agreement with the experimental observations

Multicentric Castleman's disease as a cause for unclear febrile episodes in a 55-year-old HIV-infected man

Our case illustrates the difficulties involved in diagnosing multicentric Castleman's disease (MCD) in a human immunodeficiency virus-infected man with febrile episodes and malaise. In the absence of well-established treatment protocols, we have chosen a new treatment algorithm with rituximab, etoposide, and valganciclovir, which led to the remission of clinical symptoms. Yet, we advocate focused exploration for MCD in immunosuppressed patients with unclear febrile episodes, as recent advances in treatment are promisin

Immunophenotyping without antibodies: New perspectives for lymphoma characterization

Aims: Accurate classification of haematological malignancies is a prerequisite for their correct diagnosis, prognosis and therapy. Clear classification of lymphomas is often hindered by the limited number of available cell surface protein markers that are suitable for immunophenotyping. A systematic and quantitative analysis of cell surface proteins is thus required to identify new protein markers on lymphoma subtypes in an unbiased and discovery-driven approach. Methods: Nine Hodgkin and non-Hodgkin B cell lines of diffuse large cell type and mediastinal type were investigated by cell surface capture (CSC) technology, a mass spectrometry-based method to identify cell surface glycoproteins. Selected proteins are verified by antibody-based methods, including flow cytometry and immunohistochemistry on cell line arrays. Results: A total of 747 predicted transmembrane proteins were identified from all cell lines, including 142 CD (cluster of differentiation) annotated proteins. A group of differentially expressed cell surface glycoproteins between Hodgkin and non-Hodgkin B cell lines was revealed via quantitative CSC technology. In addition to classical and expected CD molecules such as CD20 and CD30, less frequently expressed molecules such as CD2 on Hodgkin lymphoma (HL) cell lines were identified by CSC and verified by immunohistochemistry in cell lines and primary lymphoma tissue. A panel of CSC-identified differentiation glycoprotein candidates is currently under investigation on tissue microarrays (TMAs) from patient sample

Impact of duration of chest tube drainage on pain after cardiac surgery

Objective: This study was designed to analyze the duration of chest tube drainage on pain intensity and distribution after cardiac surgery. Methods: Two groups of 80 cardiac surgery adult patients, operated on in two different hospitals, by the same group of cardiac surgeons, and with similar postoperative strategies, were compared. However, in one hospital (long drainage group), a conservative policy was adopted with the removal the chest tubes by postoperative day (POD) 2 or 3, while in the second hospital (short drainage group), all the drains were usually removed on POD 1. Results: There was a trend toward less pain in the short drainage group, with a statistically significant difference on POD 2 (P=0.047). There were less patients without pain on POD 3 in the long drainage group (P=0.01). The areas corresponding to the tract of the pleural tube, namely the epigastric area, the left basis of the thorax, and the left shoulder were more often involved in the long drainage group. There were three pneumonias in each group and no patient required repeated drainage. Conclusions: A policy of early chest drain ablation limits pain sensation and simplifies nursing care, without increasing the need for repeated pleural puncture. Therefore, a policy of short drainage after cardiac surgery should be recommende

Conceptual design study for heat exhaust management in the ARC fusion pilot plant

The ARC pilot plant conceptual design study has been extended beyond its initial scope [B. N. Sorbom et al., FED 100 (2015) 378] to explore options for managing ~525 MW of fusion power generated in a compact, high field (B_0 = 9.2 T) tokamak that is approximately the size of JET (R_0 = 3.3 m). Taking advantage of ARC's novel design - demountable high temperature superconductor toroidal field (TF) magnets, poloidal magnetic field coils located inside the TF, and vacuum vessel (VV) immersed in molten salt FLiBe blanket - this follow-on study has identified innovative and potentially robust power exhaust management solutions.Comment: Accepted by Fusion Engineering and Desig

Rapid short-pulse sequences enhance the spatiotemporal uniformity of acoustically driven microbubble activity during flow conditions

Despite the promise of microbubble-mediated focused ultrasound therapies, in vivo findings have revealed over-treated and under-treated regions distributed throughout the focal volume. This poor distribution cannot be improved by conventional pulse shapes and sequences, due to their limited ability to control acoustic cavitation dynamics within the ultrasonic focus. This paper describes the design of a rapid short-pulse (RaSP) sequence which is comprised of short pulses separated by μs off-time intervals. Improved acoustic cavitation distribution was based on the hypothesis that microbubbles can freely move during the pulse off-times. Flowing SonoVue® microbubbles (flow velocity: 10 mm/s) were sonicated with a 0.5 MHz focused ultrasound transducer using RaSP sequences (peak-rarefactional pressures: 146–900 kPa, pulse repetition frequency: 1.25 kHz, and pulse lengths: 5–50 cycles). The distribution of cavitation activity was evaluated using passive acoustic mapping. RaSP sequences generated uniform distributions within the focus in contrast to long pulses (50 000 cycles) that produced non-uniform distributions. Fast microbubble destruction occurred for long pulses, whereas microbubble activity was sustained for longer durations for shorter pulses. High-speed microscopy revealed increased mobility in the direction of flow during RaSP sonication. In conclusion, RaSP sequences produced spatiotemporally uniform cavitation distributions and could result in efficient therapies by spreading cavitation throughout the treatment area