94 research outputs found

    High-latitude artificial aurora using the EISCAT high-gain HF facility

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    The EISCAT high-frequency (HF) transmitter facility at Ramfjord, Norway, has been used to accelerate F-region electrons sufficiently to excite the oxygen atoms and nitrogen molecules, resulting in optical emissions at 630, 557.7 and 427.8 nm. During O-mode transmissions at 5.423 MHz, using 630 MW effective radiated power, in the hours after sunset on 12 November 2001 several new observations were made, including: (1) The first high-latitude observation of an HF induced optical emission at 427.8 nm and (2) Optical rings being formed at HF on followed by their collapse into a central blob. Both discoveries remain unexplained with current theories

    Exhaled breath condensate pH as a biomarker of COPD severity in ex-smokers

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    Endogenous airway acidification, as assessed by exhaled breath condensate (EBC) pH, is present in patients with stable COPD. The aim of this study was to measure EBC pH levels in a large cohort of COPD patients and to evaluate associations with functional parameters according to their smoking status

    Avoiding pitfalls in interdisciplinary education

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    As the world's social-environmental problems increasingly extend across boundaries, both disciplinary and political, there is a growing need for interdisciplinarity, not only in research per se, but also in doctoral education. We present the common pitfalls of interdisciplinary research in doctoral education, illustrating approaches towards solutions using the Nordic Centre for Research on Marine Ecosystems and Resources under Climate Change (NorMER) research network as a case study. We provide insights and detailed examples of how to overcome some of the challenges of conducting interdisciplinary research within doctoral studies that can be applied within any doctoral/postdoctoral education programme, and beyond. Results from a self-evaluation survey indicate that early-career workshops, annual meetings and research visits to other institutions were the most effective learning mechanisms, whereas single discipline-focused courses and coursework were among the least effective learning mechanisms. By identifying the strengths and weaknesses of components of NorMER, this case study can inform the design of future programmes to enhance interdisciplinarity in doctoral education, as well as be applied to science collaboration and academic research in general.Peer reviewe

    Human Cytomegalovirus Induces TGF-β1 Activation in Renal Tubular Epithelial Cells after Epithelial-to-Mesenchymal Transition

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    Human cytomegalovirus (HCMV) infection is associated epidemiologically with poor outcome of renal allografts due to mechanisms which remain largely undefined. Transforming growth factor-β1 (TGF-β1), a potent fibrogenic cytokine, is more abundant in rejecting renal allografts that are infected with either HCMV or rat CMV as compared to uninfected, rejecting grafts. TGF-β1 induces renal fibrosis via epithelial-to-mesenchymal transition (EMT) of renal epithelial cells, a process by which epithelial cells acquire mesenchymal characteristics and a migratory phenotype, and secrete molecules associated with extracellular matrix deposition and remodeling. We report that human renal tubular epithelial cells infected in vitro with HCMV and exposed to TGF-β1 underwent morphologic and transcriptional changes of EMT, similar to uninfected cells. HCMV infected cells after EMT also activated extracellular latent TGF-β1 via induction of MMP-2. Renal epithelial cells transiently transfected with only the HCMV IE1 or IE2 open reading frames and stimulated to undergo EMT also induced TGF-β1 activation associated with MMP-2 production, suggesting a role for these viral gene products in MMP-2 production. Consistent with the function of these immediate early gene products, the antiviral agents ganciclovir and foscarnet did not inhibit TGF-β1 production after EMT by HCMV infected cells. These results indicate that HCMV infected renal tubular epithelial cells can undergo EMT after exposure to TGF-β1, similar to uninfected renal epithelial cells, but that HCMV infection by inducing active TGF-β1 may potentiate renal fibrosis. Our findings provide in vitro evidence for a pathogenic mechanism that could explain the clinical association between HCMV infection, TGF-β1, and adverse renal allograft outcome

    The Compact Linear Collider (CLIC) - 2018 Summary Report

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    The Compact Linear Collider (CLIC) - 2018 Summary Report

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    The Compact Linear Collider (CLIC) is a TeV-scale high-luminosity linear e+ee^+e^- collider under development at CERN. Following the CLIC conceptual design published in 2012, this report provides an overview of the CLIC project, its current status, and future developments. It presents the CLIC physics potential and reports on design, technology, and implementation aspects of the accelerator and the detector. CLIC is foreseen to be built and operated in stages, at centre-of-mass energies of 380 GeV, 1.5 TeV and 3 TeV, respectively. CLIC uses a two-beam acceleration scheme, in which 12 GHz accelerating structures are powered via a high-current drive beam. For the first stage, an alternative with X-band klystron powering is also considered. CLIC accelerator optimisation, technical developments and system tests have resulted in an increased energy efficiency (power around 170 MW) for the 380 GeV stage, together with a reduced cost estimate at the level of 6 billion CHF. The detector concept has been refined using improved software tools. Significant progress has been made on detector technology developments for the tracking and calorimetry systems. A wide range of CLIC physics studies has been conducted, both through full detector simulations and parametric studies, together providing a broad overview of the CLIC physics potential. Each of the three energy stages adds cornerstones of the full CLIC physics programme, such as Higgs width and couplings, top-quark properties, Higgs self-coupling, direct searches, and many precision electroweak measurements. The interpretation of the combined results gives crucial and accurate insight into new physics, largely complementary to LHC and HL-LHC. The construction of the first CLIC energy stage could start by 2026. First beams would be available by 2035, marking the beginning of a broad CLIC physics programme spanning 25-30 years

    Do Suicide Attempts of Mood Disorder Patients Directly Increase the Risk for a Reattempt?

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    Background: Preceding suicide attempts strongly predict future suicidal acts. However, whether attempting suicide per se increases the risk remains undetermined. We longitudinally investigated among patients with mood disorders whether after a suicide attempt future attempts occur during milder depressive states, indicating a possible lowered threshold for acting. Methods: We used 5-year follow-up data from 581 patients of the Jorvi Bipolar Study, Vantaa Depression Study, and Vantaa Primary Care Depression Study cohorts. Lifetime suicide attempts were investigated at baseline and during the follow-up. At follow-up interviews, life-chart data on the course of the mood disorder were generated and suicide attempts timed. By using individual-level data and multilevel modeling, we investigated at each incident attempt the association between the lifetime ordinal number of the attempt and the major depressive episode (MDE) status (full MDE, partial remission, or remission). Results: A total of 197 suicide attempts occurred among 90 patients, most during MDEs. When the dependencies between observations and individual liabilities were modeled, no association was found between the number of past suicide attempts at the time of each attempt and partial remissions. No association between adjusted inter-suicide attempt times and the number of past attempts emerged during follow-up. No indication for direct risk-increasing effects was found. Conclusion: Among mood disorder patients, repeated suicide attempts do not tend to occur during milder depressive states than in the preceding attempts. Previous suicide attempts may indicate underlying diathesis, future risk being principally set by the course of the disorder itself.Peer reviewe
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