274 research outputs found

    On auroral dynamics observed by HF radar: 1. Equatorward edge of the afternoon-evening diffuse luminosity belt

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    International audienceObservations and modelling are presented which illustrate the ability of the Finland CUTLASS HF radar to monitor the afternoon-evening equatorward auroral boundary during weak geomagnetic activity. The subsequent substorm growth phase development was also observed in the late evening sector as a natural continuation of the preceding auroral oval dynamics. Over an 8 h period the CUTLASS Finland radar observed a narrow (in range) and persistent region of auroral F- and (later) E-layer echoes which gradually moved equatorward, consistent with the auroral oval diurnal rotation. This echo region corresponds to the subvisual equatorward edge of the diffuse luminosity belt (SEEL) and the ionospheric footprint of the inner boundary of the electron plasma sheet. The capability of the Finland CUTLASS radar to monitor the E-layer SEEL-echoes is a consequence of the nearly zero E-layer rectilinear aspect angles in a region 5?10° poleward of the radar site. The F-layer echoes are probably the boundary blob echoes. The UHF EISCAT radar was in operation and observed a similar subvisual auroral arc and an F-layer electron density enhancement when it appeared in its antenna beam.Key words: Ionsophere (ionospheric irregularities) · Magnetospheric physics (auroral phenomena; magnetosphere?ionosphere interactions

    GOMOS: Gobal Ozone Monitoring by Occultation of Stars

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    In this paper we report on the progress and status of the Global Ozone Monitoring by Occultation of Stars (GOMOS) instrument, and imaging spectrometer under development for flight on the European Space Agency's Polar Orbiting Earth Mission (POEM-1) mission in 1998. Employing occultation of stars as a light probe of the Earth's atmosphere from a sun-sychronous polar orbit, the instrument will monitor ozone and other atmospheric trace gases over the entire globe. Atmospheric transmission resolution of approximately 1.7 km. When data are combined regionally, it will be possible to detect ozone concentration trends as small as 0.05 percent/year, depending on the degree of combination

    GPR surveys and RPA aerial photography using in conducting geocryological studies on the Oka plateau in the Eastern Sayan ridge

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    The results of ground-penetrating radar (GPR) studies of permafrost and aerial photography, carried out at key sites in the Sentsa River valley (Oka Plateau, Eastern Sayan Ridge), are presented.For geophysical studies, an OKO-2 GPR completed with an AB-90 shielded antenna unit was used with a maximum sounding depth of up to 20 m and a resolution of 0.5 m. To account for the landscape elevation, the Trimble TS635 tacheometer and the Leiсa DISTO D 510 rangefinder performed hypsometric measurements with a step of 1.0 m. Aerial photography was carried out by a remotely piloted aircraft (RPA) DJI Inspire 1 Pro, equipped with a Zenmuse 3X camera (a resolution of 3840×2160 pixels) with a spatial resolution of 5.7–7.8 cm/pixel (in different years).In the structure of frozen lacustrine-alluvial sediments, three GPR complexes are distinguished, corresponding to the active layer and frozen rocks with different amounts of schlieren, lenses and layers of texture-forming ice. The orthophoto map and tacheometric survey analysis showed that the destruction of frost mounds occurs from the second half of April to the first half of October. The most significant relief change is due to the thawing of icy pulverescent clayey silts. It leads to subsidence blocks in the ledge of the Sentsa River terrace. Lateral river thermoerosion also contributes to the frost mounds destruction

    Associations of PTEN and ERG with Magnetic Resonance Imaging Visibility and Assessment of Non–organ-confined Pathology and Biochemical Recurrence After Radical Prostatectomy

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    Background: Diagnosing clinically significant prostate cancer (PCa) is challenging, but may be facilitated by biomarkers and multiparametric magnetic resonance imaging (MRI). Objective: To determine the association between biomarkers phosphatase and tensin homolog (PTEN) and ETS-related gene (ERG) with visible and invisible PCa lesions in MRI, and to predict biochemical recurrence (BCR) and non-organ-confined (non-OC) PCa by integrating clinical, MRI, and biomarker-related data. Design, setting, and participants: A retrospective analysis of a population-based cohort of men with PCa, who underwent preoperative MRI followed by radical prostatectomy (RP) during 2014-2015 in Helsinki University Hospital (n = 346), was conducted. A tissue microarray corresponding to the MRI-visible and MRI-invisible lesions in RP specimens was constructed and stained for PTEN and ERG. Outcome measurements and statistical analysis: Associations of PTEN and ERG with MRI-visible and MRI-invisible lesions were examined (Pearson's chi 2 test), and predictions of non-OC disease together with clinical and MRI parameters were determined (area under the receiver operating characteristic curve and logistic regression analyses). BCR prediction was analyzed by Kaplan-Meier and Cox proportional hazard analyses. Results and limitations: Patients with MRI-invisible lesions (n = 35) had less PTEN loss and ERG-positive expression compared with patients (n = 90) with MRI-visible lesions (17.2% vs 43.3% [p = 0.006]; 8.6% vs 20.0% [p = 0.125]). Patients with invisible lesions had better, but not statistically significantly improved, BCR-free survival probability in Kaplan-Meier analyses (p = 0.055). Rates of BCR (5.7% vs 21.1%; p = 0.039), extraprostatic extension (11.4% vs 44.6%; p < 0.001), seminal vesicle invasion (0% vs 21.1%; p = 0.003), and lymph node metastasis (0% vs 12.2%; p = 0.033) differed between the groups in favor of patients with MRI-invisible lesions. Biomarkers had no independent role in predicting non-OC disease or BCR. The short follow-up period was a limitation. Conclusions: PTEN loss, BCR, and non-OC RP findings were more often encountered with MRI-visible lesions. Patient summary: Magnetic resonance imaging (MRI) of the prostate misses some cancer lesions. MRI-invisible lesions seem to be less aggressive than MRI-visible lesions. (C) 2020 European Association of Urology. Published by Elsevier B.V. All rights reserved.Peer reviewe

    Beta 1-integrin-c-Met cooperation reveals an inside-in survival signalling on autophagy-related endomembranes

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    This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/R.B.M. was a recipient of a UK Medical Research Council (MRC) studentship, MRC Centenary Award, Barts and The London Charity (472/1711) and Rosetrees Trust (M314), N.K. was a recipient of an MRC studentship (MR/J500409/1), C.J. was a recipient of the Barts and The London Charitable Foundation Scholarship (RAB 05/PJ/07), L.M. was supported by CR-UK, Breast Cancer Now (2008NovPR10) and Rosetrees Trust (M346), A.H. was a recipient of a CR-UK studentship (C236/A11795). P.J.P. was supported by CR-UK. J.I. was supported by grants from the Academy of Finland, ERC Starting grant, Finnish Cancer Organisations and Sigrid Juselius Foundation. S.K. was supported by the MRC (G0501003) and The British Lung Foundation (CAN09-4)
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