Magnetic reconnection is important to the dynamics of many astrophysical and fusion plasmas but our understanding of it is incomplete. Petaflop-scale simulations of the evolution of turbulent ...magnetic reconnection in a three-dimensional plasma indicate that it proceeds in a way that is dramatically different from classical theory. PUBLICATION ABSTRACT
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IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this work we present the first fully-integrated free-space beam-steering chip using the hybrid silicon platform. The photonic integrated circuit (PIC) consists of 164 optical components including ...lasers, amplifiers, photodiodes, phase tuners, grating couplers, splitters, and a photonic crystal lens. The PIC exhibited steering over 23° x 3.6° with beam widths of 1° x 0.6°.
A hybrid silicon tunable Vernier ring laser is designed and fabricated by integration of two intra-cavity ring resonators, hybrid III-V-on-silicon gain elements, and resistive heaters for thermal ...tuning. Thermal tuning of more than 40 nm is demonstrated with side mode suppression ratio greater than 35 dB and linewidth of 338 kHz.
We demonstrate a 16-channel, independently tuned waveguide surface grating optical phased array in silicon for two dimensional beam steering with a total field of view of 20° x 14°, beam width of ...0.6° x 1.6°, and full-window background peak suppression of 10 dB.
We demonstrate a novel integrated silicon and ultra-low-loss Si3N4 waveguide platform. Coupling between layers is achieved with (0.4 ± 0.2) dB of loss per transition and a 20 nm 3-dB bandwidth for ...one tapered coupler design and with (0.8 ± 0.2) dB of loss per transition and a 100 nm 3-dB bandwidth for another. The minimum propagation loss measured in the ultra-low-loss waveguides is 1.2 dB/m in the 1590 nm wavelength regime.
Breakout afterburner (BOA) laser-ion acceleration has been demonstrated for the first time in the laboratory. In the BOA, an initially solid-density target undergoes relativistically induced ...transparency, initiating a period of enhanced ion acceleration. First-ever kinetic simulations of the BOA in three dimensions show that the ion beam forms lobes in the direction orthogonal to laser polarization and propagation. Analytic theory presented for the electron dynamics in the laser ponderomotive field explains how azimuthal symmetry breaks even for a symmetric laser intensity profile; these results are consistent with recent experiments at the Trident laser facility.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We report on the acceleration of ion beams from ultrathin diamondlike carbon foils of thickness 50, 30, and 10 nm irradiated by ultrahigh contrast laser pulses at intensities of approximately 7 x ...10;{19} W/cm;{2}. An unprecedented maximum energy of 185 MeV (15 MeV/u) for fully ionized carbon atoms is observed at the optimum thickness of 30 nm. The enhanced acceleration is attributed to self-induced transparency, leading to strong volumetric heating of the classically overdense electron population in the bulk of the target. Our experimental results are supported by both particle-in-cell (PIC) simulations and an analytical model.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The development of epithelial-to-mesenchymal transition (EMT) like features is emerging as a critical factor involved in the pathogenesis of acute myeloid leukaemia (AML). However, the extracellular ...signals and the signalling pathways in AML that may regulate EMT remain largely unstudied. We found that the bone marrow (BM) mesenchymal/fibroblastic cell line HS5 induces an EMT-like migratory phenotype in AML cells. AML cells underwent a strong increase of vimentin (VIM) levels that was not mirrored to the same extent by changes of expression of the other EMT core proteins SNAI1 and SNAI2. We validated these particular pattern of co-expression of core-EMT markers in AML cells by performing an in silico analysis using datasets of human tumours. Our data showed that in AML the expression levels of VIM does not completely correlate with the co-expression of core EMT markers observed in epithelial tumours. We also found that vs epithelial tumours, AML cells display a distinct patterns of co-expression of VIM and the actin binding and adhesion regulatory proteins that regulate F-actin dynamics and integrin-mediated adhesions involved in the invasive migration in cells undergoing EMT. We conclude that the BM stroma induces an EMT related pattern of migration in AML cells in a process involving a distinctive regulation of EMT markers and of regulators of cell adhesion and actin dynamics that should be further investigated. Understanding the tumour specific signalling pathways associated with the EMT process may contribute to the development of new tailored therapies for AML as well as in different types of cancers.
•Bone marrow mesenchymal fibroblastic stromal cells induce a migratory EMT-like phenotype in AML cells.•AML cells present a distinctive pattern of co-upregulation of vimentin and other core-EMT markers that differs from epithelial tumours.•AML cells undergoing an EMT-like process show similarities as well as distinctive differences vs epithelial tumours in the pattern of co-expression of vimentin and the regulators of F-actin and cell adhesion dynamics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Existing methods of predicting and mapping the future locations of crime are intrinsically retrospective. This paper explores the development of a mapping procedure that seeks to produce ...'prospective' hot-spot maps. Recent research conducted by the authors demonstrates that the risk of burglary is communicable, with properties within 400 metres of a burgled household being at a significantly elevated risk of victimization for up to two months after an initial event. We discuss how, using this knowledge, recorded crime data can be analysed to generate an ever-changing prospective risk surface. One of the central elements of this paper examines the issue of how such a risk surface could be evaluated to determine its effectiveness and utility in comparison to existing methods. New methods of map evaluation are proposed, such as the production of search efficiency rates and area-to-perimeter ratios; standardized metrics that can be derived for maps produced using different techniques, thereby allowing meaningful comparisons to be made and techniques contrasted. The results suggest that the predictive mapping technique proposed here has considerable advantages over more traditional methods and might prove particularly useful in the shift-by-shift deployment of police personnel.
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BFBNIB, NMLJ, NUK, PNG, PRFLJ, UL, UM, UPUK
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