| 1. |
- Aad, G., et al.
(author)
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- 2013
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Journal article (peer-reviewed)
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| 2. |
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- 2017
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In: Physical Review D. - 2470-0010 .- 2470-0029. ; 96:2
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Journal article (peer-reviewed)
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| 3. |
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Overview of the JET results
- 2015
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In: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 55:10
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Journal article (peer-reviewed)
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| 4. |
- Romanelli, F, et al.
(author)
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Overview of the JET results
- 2011
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 51:9
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Journal article (peer-reviewed)abstract
- Since the last IAEA Conference JET has been in operation for one year with a programmatic focus on the qualification of ITER operating scenarios, the consolidation of ITER design choices and preparation for plasma operation with the ITER-like wall presently being installed in JET. Good progress has been achieved, including stationary ELMy H-mode operation at 4.5 MA. The high confinement hybrid scenario has been extended to high triangularity, lower ρ*and to pulse lengths comparable to the resistive time. The steady-state scenario has also been extended to lower ρ*and ν*and optimized to simultaneously achieve, under stationary conditions, ITER-like values of all other relevant normalized parameters. A dedicated helium campaign has allowed key aspects of plasma control and H-mode operation for the ITER non-activated phase to be evaluated. Effective sawtooth control by fast ions has been demonstrated with3He minority ICRH, a scenario with negligible minority current drive. Edge localized mode (ELM) control studies using external n = 1 and n = 2 perturbation fields have found a resonance effect in ELM frequency for specific q95values. Complete ELM suppression has, however, not been observed, even with an edge Chirikov parameter larger than 1. Pellet ELM pacing has been demonstrated and the minimum pellet size needed to trigger an ELM has been estimated. For both natural and mitigated ELMs a broadening of the divertor ELM-wetted area with increasing ELM size has been found. In disruption studies with massive gas injection up to 50% of the thermal energy could be radiated before, and 20% during, the thermal quench. Halo currents could be reduced by 60% and, using argon/deuterium and neon/deuterium gas mixtures, runaway electron generation could be avoided. Most objectives of the ITER-like ICRH antenna have been demonstrated; matching with closely packed straps, ELM resilience, scattering matrix arc detection and operation at high power density (6.2 MW m-2) and antenna strap voltages (42 kV). Coupling measurements are in very good agreement with TOPICA modelling. © 2011 IAEA, Vienna.
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| 5. |
- Abel, I, et al.
(author)
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Overview of the JET results with the ITER-like wall
- 2013
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In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10, s. 104002-
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Journal article (peer-reviewed)abstract
- Following the completion in May 2011 of the shutdown for the installation of the beryllium wall and the tungsten divertor, the first set of JET campaigns have addressed the investigation of the retention properties and the development of operational scenarios with the new plasma-facing materials. The large reduction in the carbon content (more than a factor ten) led to a much lower Z(eff) (1.2-1.4) during L- and H-mode plasmas, and radiation during the burn-through phase of the plasma initiation with the consequence that breakdown failures are almost absent. Gas balance experiments have shown that the fuel retention rate with the new wall is substantially reduced with respect to the C wall. The re-establishment of the baseline H-mode and hybrid scenarios compatible with the new wall has required an optimization of the control of metallic impurity sources and heat loads. Stable type-I ELMy H-mode regimes with H-98,H-y2 close to 1 and beta(N) similar to 1.6 have been achieved using gas injection. ELM frequency is a key factor for the control of the metallic impurity accumulation. Pedestal temperatures tend to be lower with the new wall, leading to reduced confinement, but nitrogen seeding restores high pedestal temperatures and confinement. Compared with the carbon wall, major disruptions with the new wall show a lower radiated power and a slower current quench. The higher heat loads on Be wall plasma-facing components due to lower radiation made the routine use of massive gas injection for disruption mitigation essential.
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| 6. |
- Klionsky, Daniel J., et al.
(author)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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In: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Research review (peer-reviewed)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 7. |
- Feroci, M., et al.
(author)
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The Large Observatory for X-ray Timing (LOFT)
- 2012
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In: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 34:2, s. 415-444
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Journal article (peer-reviewed)abstract
- High-time-resolution X-ray observations of compact objects provide direct access to strong-field gravity, to the equation of state of ultradense matter and to black hole masses and spins. A 10 m(2)-class instrument in combination with good spectral resolution is required to exploit the relevant diagnostics and answer two of the fundamental questions of the European Space Agency (ESA) Cosmic Vision Theme "Matter under extreme conditions", namely: does matter orbiting close to the event horizon follow the predictions of general relativity? What is the equation of state of matter in neutron stars? The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionise the study of collapsed objects in our galaxy and of the brightest supermassive black holes in active galactic nuclei. Thanks to an innovative design and the development of large-area monolithic silicon drift detectors, the Large Area Detector (LAD) on board LOFT will achieve an effective area of similar to 12 m(2) (more than an order of magnitude larger than any spaceborne predecessor) in the 2-30 keV range (up to 50 keV in expanded mode), yet still fits a conventional platform and small/medium-class launcher. With this large area and a spectral resolution of < 260 eV, LOFT will yield unprecedented information on strongly curved spacetimes and matter under extreme conditions of pressure and magnetic field strength.
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| 8. |
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Blanton, Michael R., et al.
(author)
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Sloan Digital Sky Survey IV : Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
- 2017
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In: Astronomical Journal. - : IOP Publishing Ltd. - 0004-6256 .- 1538-3881. ; 154:1
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Journal article (peer-reviewed)abstract
- We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and. high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z similar to 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z similar to 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs. and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the. Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July.
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| 13. |
- Abolfathi, Bela, et al.
(author)
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The Fourteenth Data Release of the Sloan Digital Sky Survey : First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
- 2018
-
In: Astrophysical Journal Supplement Series. - : IOP Publishing Ltd. - 0067-0049 .- 1538-4365. ; 235:2
-
Journal article (peer-reviewed)abstract
- The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014-2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V.
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| 14. |
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| 15. |
- Lappalainen, H. K., et al.
(author)
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Overview: Recent advances in the understanding of the northern Eurasian environments and of the urban air quality in China - a Pan-Eurasian Experiment (PEEX) programme perspective
- 2022
-
In: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 22:7, s. 4413-4469
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Journal article (peer-reviewed)abstract
- The Pan-Eurasian Experiment (PEEX) Science Plan, released in 2015, addressed a need for a holistic system understanding and outlined the most urgent research needs for the rapidly changing Arctic-boreal region. Air quality in China, together with the long-range transport of atmospheric pollutants, was also indicated as one of the most crucial topics of the research agenda. These two geographical regions, the northern Eurasian Arctic-boreal region and China, especially the megacities in China, were identified as a "PEEX region". It is also important to recognize that the PEEX geographical region is an area where science-based policy actions would have significant impacts on the global climate. This paper summarizes results obtained during the last 5 years in the northern Eurasian region, together with recent observations of the air quality in the urban environments in China, in the context of the PEEX programme. The main regions of interest are the Russian Arctic, northern Eurasian boreal forests (Siberia) and peatlands, and the megacities in China. We frame our analysis against research themes introduced in the PEEX Science Plan in 2015. We summarize recent progress towards an enhanced holistic understanding of the land-atmosphere-ocean systems feedbacks. We conclude that although the scientific knowledge in these regions has increased, the new results are in many cases insufficient, and there are still gaps in our understanding of large-scale climate-Earth surface interactions and feedbacks. This arises from limitations in research infrastructures, especially the lack of coordinated, continuous and comprehensive in situ observations of the study region as well as integrative data analyses, hindering a comprehensive system analysis. The fast-changing environment and ecosystem changes driven by climate change, socio-economic activities like the China Silk Road Initiative, and the global trends like urbanization further complicate such analyses. We recognize new topics with an increasing importance in the near future, especially "the enhancing biological sequestration capacity of greenhouse gases into forests and soils to mitigate climate change" and the "socio-economic development to tackle air quality issues".
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| 16. |
- Sloot, Frea, et al.
(author)
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Inventory of current EU paediatric vision and hearing screening programmes
- 2015
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In: Journal of Medical Screening. - : SAGE Publications. - 0969-1413 .- 1475-5793. ; 22:2, s. 55-64
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Journal article (peer-reviewed)abstract
- Objective: To examine the diversity in paediatric vision and hearing screening programmes in Europe. Methods: Themes for comparison of screening programmes derived from literature were used to compile three questionnaires on vision, hearing, and public health screening. Tests used, professions involved, age, and frequency of testing seem to influence sensitivity, specificity, and costs most. Questionnaires were sent to ophthalmologists, orthoptists, otolaryngologists, and audiologists involved in paediatric screening in all EU full-member, candidate, and associate states. Answers were cross-checked. Results: Thirty-nine countries participated; 35 have a vision screening programme, 33 a nation-wide neonatal hearing screening programme. Visual acuity (VA) is measured in 35 countries, in 71% of these more than once. First measurement of VA varies from three to seven years of age, but is usually before age five. At age three and four, picture charts, including Lea Hyvarinen, are used most; in children over four, Tumbling-E and Snellen. As first hearing screening test, otoacoustic emission is used most in healthy neonates, and auditory brainstem response in premature newborns. The majority of hearing testing programmes are staged; children are referred after 1–4 abnormal tests. Vision screening is performed mostly by paediatricians, ophthalmologists, or nurses. Funding is mostly by health insurance or state. Coverage was reported as >95% in half of countries, but reporting was often not first-hand. Conclusion: Largest differences were found in VA charts used (12), professions involved in vision screening (10), number of hearing screening tests before referral (1–4), and funding sources (8).
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| 17. |
- Pironi, L., et al.
(author)
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Clinical classification of adult patients with chronic intestinal failure due to benign disease: An international multicenter cross-sectional survey
- 2018
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In: Clinical Nutrition. - : Elsevier BV. - 0261-5614. ; 37:2, s. 728-738
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Journal article (peer-reviewed)abstract
- Background & aims: The aim of the study was to evaluate the applicability of the ESPEN 16-category clinical classification of chronic intestinal failure, based on patients' intravenous supplementation (IVS) requirements for energy and fluids, and to evaluate factors associated with those requirements. Methods: ESPEN members were invited to participate through ESPEN Council representatives. Participating centers enrolled adult patients requiring home parenteral nutrition for chronic intestinal failure on March 1st 2015. The following patient data were recorded though a structured database: sex, age, body weight and height, intestinal failure mechanism, underlying disease, IVS volume and energy need. Results: Sixty-five centers from 22 countries enrolled 2919 patients with benign disease. One half of the patients were distributed in 3 categories of the ESPEN clinical classification. 9% of patients required only fluid and electrolyte supplementation. IVS requirement varied considerably according to the pathophysiological mechanism of intestinal failure. Notably, IVS volume requirement represented loss of intestinal function better than IVS energy requirement. A simplified 8 category classification of chronic intestinal failure was devised, based on two types of IVS (either fluid and electrolyte alone or parenteral nutrition admixture containing energy) and four categories of volume. Conclusions: Patients' IVS requirements varied widely, supporting the need for a tool to homogenize patient categorization. This study has devised a novel, simplified eight category IVS classification for chronic intestinal failure that will prove useful in both the clinical and research setting when applied together with the underlying pathophysiological mechanism of the patient's intestinal failure. (C) 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
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| 18. |
- Dyer, A. H., et al.
(author)
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Cognitive Outcomes of Long-term Benzodiazepine and Related Drug (BDZR) Use in People Living With Mild to Moderate Alzheimer's Disease: Results From NILVAD
- 2020
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In: Journal of the American Medical Directors Association. - : Elsevier BV. - 1525-8610. ; 21:2, s. 194-200
-
Journal article (peer-reviewed)abstract
- Objective: Benzodiazepines and related drugs (BDZRs) have been associated with an increased risk of Alzheimer's disease (AD) in later life. Despite this, it remains unclear whether ongoing BDZR use may further accelerate cognitive decline in those diagnosed with mild to moderate AD. Design: This study was embedded within NILVAD, a randomized controlled trial of nilvadipine in mild to moderate AD. Cognition was measured at baseline and 18 months using the Alzheimer Disease Assessment Scale, Cognitive Subsection (ADAS-Cog). We assessed predictors of long-term BDZR use and analyzed the effect of ongoing BDZR use on ADAS-Cog scores at 18 months. Additionally, the impact of BDZR use on adverse events, incident delirium, and falls over 18-month follow-up was assessed adjusting for relevant covariates. Setting and Participants: 448 participants with mild to moderate AD recruited from 23 academic centers in 9 European countries. Results: Overall, 14% (62/448) were prescribed an ongoing BDZR for the study duration. Increasing total number of (non-BDZR) medications was associated with a greater likelihood of BDZR prescription (odds ratio 1.16, 95% confidence interval 1.05-1.29). At 18 months, BDZR use was not associated with greater cognitive decline on the ADAS-Cog controlling for baseline ADAS-Cog scores, age, gender, study arm, and other clinical covariates (beta = 1.62, -1.34 to 4.56). However, ongoing BDZR use was associated with a greater likelihood of adverse events [incidence rate ratio (IRR) 1.19, 1.05-1.34], incident delirium (IRR 2.31, 1.45-3.68), and falls (IRR 1.66, 1.02-2.65) over 18 months that persisted after robust adjustment for covariates. Conclusions and Implications: This study found no effect of ongoing BDZR use on ADAS-Cog scores in those with mild to moderate AD over 18 months. However, ongoing use of these medications was associated with an increased risk of adverse events, delirium, and falls. Thus, BDZR use should be avoided where possible and deprescribing interventions should be encouraged in older adults with AD. (C) 2019 AMDA - The Society for Post-Acute and Long-Term Care Medicine.
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| 19. |
- de Heus, R. A. A., et al.
(author)
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Blood Pressure Lowering With Nilvadipine in Patients With Mild-to-Moderate Alzheimer Disease Does Not Increase the Prevalence of Orthostatic Hypotension
- 2019
-
In: Journal of the American Heart Association. - : Ovid Technologies (Wolters Kluwer Health). - 2047-9980. ; 8:10
-
Journal article (peer-reviewed)abstract
- Background-Hypertension is common among patients with Alzheimer disease. Because this group has been excluded from hypertension trials, evidence regarding safety of treatment is lacking. This secondary analysis of a randomized controlled trial assessed whether antihypertensive treatment increases the prevalence of orthostatic hypotension (OH) in patients with Alzheimer disease. Methods and Results-Four hundred seventy-seven patients with mild-to-moderate Alzheimer disease were randomized to the calcium-channel blocker nilvadipine 8 mg/day or placebo for 78 weeks. Presence of OH (blood pressure drop >= 20/>= 10 mm Hg after 1 minute of standing) and OH-related adverse events (dizziness, syncope, falls, and fractures) was determined at 7 follow-up visits. Mean age of the study population was 72.2 +/- 8.2 years and mean Mini-Mental State Examination score was 20.4 +/- 3.8. Baseline blood pressure was 137.8 +/- 14.0/77.0 +/- 8.6 mm Hg. Grade I hypertension was present in 53.4% (n=255). After 13 weeks, blood pressure had fallen by -7.8/-3.9 mm Hg for nilvadipine and by -0.4/-0.8 mm Hg for placebo (P<0.001). Across the 78-week intervention period, there was no difference between groups in the proportion of patients with OH at a study visit (odds ratio [95% CI] 1.1 [0.8-1.5], P 0.62), nor in the proportion of visits where a patient met criteria for OH, corrected for number of visits (7.7 +/- 13.8% versus 7.3 +/- 11.6%). OH-related adverse events were not more often reported in the intervention group compared with placebo. Results were similar for those with baseline hypertension. Conclusions-This study suggests that initiation of a low dose of antihypertensive treatment does not significantly increase the risk of OH in patients with mild-to-moderate Alzheimer disease.
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| 20. |
- Kapun, Martin, et al.
(author)
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Drosophila Evolution over Space and Time (DEST) : A New Population Genomics Resource
- 2021
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In: Molecular biology and evolution. - : Oxford University Press (OUP). - 0737-4038 .- 1537-1719. ; 38:12, s. 5782-5805
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Journal article (peer-reviewed)abstract
- Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome data sets from natural populations of this species have been published over the last years. A major challenge is the integration of disparate data sets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 previously published and unpublished population samples from over 100 locations in >20 countries on four continents. Several of these locations have been sampled at different seasons across multiple years. This data set, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental metadata. A web-based genome browser and web portal provide easy access to the SNP data set. We further provide guidelines on how to use Pool-Seq data for model-based demographic inference. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan data set. Our resource will enable population geneticists to analyze spatiotemporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.
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| 21. |
- Loiseau, O., et al.
(author)
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Targeted Capture of Hundreds of Nuclear Genes Unravels Phylogenetic Relationships of the Diverse Neotropical Palm Tribe Geonomateae
- 2019
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In: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 10
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Journal article (peer-reviewed)abstract
- The tribe Geonomateae is a widely distributed group of 103 species of Neotropical palms which contains six ecologically important understory or subcanopy genera. Although it has been the focus of many studies, our understanding of the evolutionary history of this group, and in particular of the taxonomically complex genus Geonoma, is far from complete due to a lack of molecular data. Specifically, the previous Sanger sequencing-based studies used a few informative characters and partial sampling. To overcome these limitations, we used a recently developed Arecaceae-specific target capture bait set to undertake a phylogenomic analysis of the tribe Geonomateae. We sequenced 3,988 genomic regions for 85% of the species of the tribe, including 84% of the species of the largest genus, Geonoma. Phylogenetic relationships were inferred using both concatenation and coalescent methods. Overall, our phylogenetic tree is highly supported and congruent with taxonomic delimitations although several morphological taxa were revealed to be non-monophyletic. It is the first time that such a large genomic dataset is provided for an entire tribe within the Arecaceae. Our study lays the groundwork not only for detailed macro- and micro-evolutionary studies within the group, but also sets a workflow for understanding other species complexes across the tree of life.
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| 22. |
- van Sebille, Erik, et al.
(author)
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Lagrangian ocean analysis : Fundamentals and practices
- 2018
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In: Ocean Modelling. - : Elsevier BV. - 1463-5003 .- 1463-5011. ; 121, s. 49-75
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Research review (peer-reviewed)abstract
- Lagrangian analysis is a powerful way to analyse the output of ocean circulation models and other ocean velocity data such as from altimetry. In the Lagrangian approach, large sets of virtual particles are integrated within the three-dimensional, time-evolving velocity fields. Over several decades, a variety of tools and methods for this purpose have emerged. Here, we review the state of the art in the field of Lagrangian analysis of ocean velocity data, starting from a fundamental kinematic framework and with a focus on large-scale open ocean applications. Beyond the use of explicit velocity fields, we consider the influence of unresolved physics and dynamics on particle trajectories. We comprehensively list and discuss the tools currently available for tracking virtual particles. We then showcase some of the innovative applications of trajectory data, and conclude with some open questions and an outlook. The overall goal of this review paper is to reconcile some of the different techniques and methods in Lagrangian ocean analysis, while recognising the rich diversity of codes that have and continue to emerge, and the challenges of the coming age of petascale computing.
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| 23. |
- Waszczuk-Gajda, A, et al.
(author)
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Complications of Autologous Stem Cell Transplantation in Multiple Myeloma: Results from the CALM Study
- 2022
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In: Journal of clinical medicine. - : MDPI AG. - 2077-0383. ; 11:12
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Journal article (peer-reviewed)abstract
- Background: The main goal of this post hoc analysis of the Collaboration to Collect Autologous Transplant Outcomes in Lymphoma and Myeloma (CALM) study was to evaluate the rate of short- and long-term infectious and non-infectious complications occurring after ASCT in patients with multiple myeloma (MM). Methods: The analysis included all patients with MM from the CALM study who underwent ≥1 ASCT. The primary endpoint of the analysis was to determine the rate of infectious and non-infectious complications after ASCT and to compare them in three time periods: 0–100 days, 101 days–1 year, and >1 year after the first transplant. Results: The analysis included a total of 3552 patients followed up for a median of 56.7 months (range 0.4–108.1). Complication rates decreased with the time from ASCT with 24.85 cases per 100 patient-years from day 0 to 100 days after the transplant, and <2.31 cases per 100 patient-years from the 101st day. At 100 days after ASC T, 45.7% of patients had complications, with infectious events being twice as frequent as non-infectious complications. Bacterial infections (6.5 cases per 100 patient-years, 95% CI: 6.1–7.0) and gastrointestinal complications (4.7 cases per 100 patient-years, 95% CI: 4.3–5.1) were the most common early events. The pattern of complications changed with time from ASCT. The presence of complications after ASCT was not associated with overall survival. Conclusions: Our data provide a solid basis for comparing ASCT-related complications to those caused by emerging treatments in multiple myeloma, such as CAR T-cell therapy and other immunotherapies.
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| 24. |
- Carlson, A. D., et al.
(author)
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A new evaluation of the neutron data standards
- 2017
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In: ND 2016. - : EDP Sciences. - 9782759890200
-
Conference paper (peer-reviewed)abstract
- Evaluations are being done for the H(n,n), 6Li(n,t), 10B(n,αγ), 10B(n,α), C(n,n), Au(n,γ), 235U(n,f) and 238U(n,f) standard cross sections. Evaluations are also being done for data that are not traditional standards including: the Au(n,γ) cross section at energies below where it is considered a standard; reference cross sections for prompt gamma-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the 235U thermal neutron fission spectrum and the 252Cf spontaneous fission neutron spectrum and the thermal constants.
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| 25. |
- Carlson, A. D., et al.
(author)
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Evaluation of the Neutron Data Standards
- 2018
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In: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752 .- 1095-9904. ; 148, s. 143-188
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Journal article (peer-reviewed)abstract
- With the need for improving existing nuclear data evaluations, (e.g., ENDF/B-VIII.0 and JEFF-3.3 releases) the first step was to evaluate the standards for use in such a library. This new standards evaluation made use of improved experimental data and some developments in the methodology of analysis and evaluation. In addition to the work on the traditional standards, this work produced the extension of some energy ranges and includes new reactions that are called reference cross sections. Since the effort extends beyond the traditional standards, it is called the neutron data standards evaluation. This international effort has produced new evaluations of the following cross section standards: the H(n,n), Li-6(n,t), B-10(n, alpha), B-10(n,alpha(1)gamma), C-nat(n,n), Au(n,gamma), U-235(n,f) and U-238(n,f). Also in the evaluation process the U-238(n,gamma) and Pu-239(n,f) cross sections that are not standards were evaluated. Evaluations were also obtained for data that are not traditional standards: the Maxwellian spectrum averaged cross section for the Au(n,gamma) cross section at 30 keV; reference cross sections for prompt gamma-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the Cf-252 spontaneous fission neutron spectrum and the U-235 prompt fission neutron spectrum induced by thermal incident neutrons; and the thermal neutron constants. The data and covariance matrices of the uncertainties were obtained directly from the evaluation procedure.
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| 26. |
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| 27. |
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| 28. |
- D'Souza, Nigel, et al.
(author)
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Definition of the Rectum An International, Expert-based Delphi Consensus
- 2019
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In: Annals of Surgery. - : LIPPINCOTT WILLIAMS & WILKINS. - 0003-4932 .- 1528-1140. ; 270:6, s. 955-959
-
Journal article (peer-reviewed)abstract
- Background: The wide global variation in the definition of the rectum has led to significant inconsistencies in trial recruitment, clinical management, and outcomes. Surgical technique and use of preoperative treatment for a cancer of the rectum and sigmoid colon are radically different and dependent on the local definitions employed by the clinical team. A consensus definition of the rectum is needed to standardise treatment. Methods: The consensus was conducted using the Delphi technique with multidisciplinary colorectal experts from October, 2017 to April, 2018. Results: Eleven different definitions for the rectum were used by participants in the consensus. Magnetic resonance imaging (MRI) was the most frequent modality used to define the rectum (67%), and the preferred modality for 72% of participants. The most agreed consensus landmark (56%) was "the sigmoid take-off,'' an anatomic, image-based definition of the junction of the mesorectum and mesocolon. In the second round, 81% of participants agreed that the sigmoid take-off as seen on computed tomography or MRI achieved consensus, and that it could be implemented in their institution. Also, 87% were satisfied with the sigmoid take-off as the consensus landmark. Conclusion: An international consensus definition for the rectumis the point of the sigmoid take-off as visualized on imaging. The sigmoid take-off can be identified as the mesocolon elongates as the ventral and horizontal course of the sigmoid on axial and sagittal views respectively on cross-sectional imaging. Routine application of this landmark during multidisciplinary team discussion for all patients will enable greater consistency in tumour localisation.
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| 29. |
- Grazian, A., et al.
(author)
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Lyman continuum escape fraction of faint galaxies at z similar to 3.3 in the CANDELS/GOODS-North, EGS, and COSMOS fields with LBC
- 2017
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 602
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Journal article (peer-reviewed)abstract
- Context. The reionization of the Universe is one of the most important topics of present-day astrophysical research. The most plausible candidates for the reionization process are star-forming galaxies, which according to the predictions of the majority of the theoretical and semi-analytical models should dominate the H I ionizing background at z greater than or similar to 3. Aims. We measure the Lyman continuum escape fraction, which is one of the key parameters used to compute the contribution of star-forming galaxies to the UV background. It provides the ratio between the photons produced at lambda <= 912 angstrom rest-frame and those that are able to reach the inter-galactic medium, i.e. that are not absorbed by the neutral hydrogen or by the dust of the galaxy's inter-stellar medium. Methods. We used ultra-deep U-band imaging (U = 30.2 mag at 1 sigma) from Large Binocular Camera at the Large Binocular Telescope (LBC/LBT) in the CANDELS/GOODS-North field and deep imaging in the COSMOS and EGS fields in order to estimate the Lyman continuum escape fraction of 69 star-forming galaxies with secure spectroscopic redshifts at 3.27 <= z <= 3.40 to faint magnitude limits (L = 0.2L*, or equivalently M-1500 similar to -19). The narrow redshift range implies that the LBC U-band filter exclusively samples the lambda <= 912 angstrom rest-frame wavelengths. Results. We measured through stacks a stringent upper limit (<1.7% at 1 sigma) for the relative escape fraction of H I ionizing photons from bright galaxies (L > L*), while for the faint population (L = 0.2L*) the limit to the escape fraction is less than or similar to 10%. We computed the contribution of star-forming galaxies to the observed UV background at z similar to 3 and find that it is not sufficient to keep the Universe ionized at these redshifts unless their escape fraction increases significantly (>= 10%) at low luminosities (M-1500 >= -19). Conclusions. We compare our results on the Lyman continuum escape fraction of high-z galaxies with recent estimates in the literature, and discuss future prospects to shed light on the end of the Dark Ages. In the future, strong gravitational lensing will be fundamental in order to measure the Lyman continuum escape fraction down to faint magnitudes (M-1500 similar to -16) that are inaccessible with the present instrumentation on blank fields. These results will be important in order to quantify the role of faint galaxies to the reionization budget.
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| 30. |
- Jung, Christian, et al.
(author)
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A comparison of very old patients admitted to intensive care unit after acute versus elective surgery or intervention
- 2019
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In: Journal of critical care. - : W B SAUNDERS CO-ELSEVIER INC. - 0883-9441 .- 1557-8615. ; 52, s. 141-148
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Journal article (peer-reviewed)abstract
- Background: We aimed to evaluate differences in outcome between patients admitted to intensive care unit (ICU) after elective versus acute surgery in a multinational cohort of very old patients (80 years; VIP). Predictors of mortality, with special emphasis on frailty, were assessed.Methods: In total, 5063 VIPs were induded in this analysis, 922 were admitted after elective surgery or intervention, 4141 acutely, with 402 after acute surgery. Differences were calculated using Mann-Whitney-U test and Wilcoxon test. Univariate and multivariable logistic regression were used to assess associations with mortality.Results: Compared patients admitted after acute surgery, patients admitted after elective surgery suffered less often from frailty as defined as CFS (28% vs 46%; p < 0.001), evidenced lower SOFA scores (4 +/- 5 vs 7 +/- 7; p < 0.001). Presence of frailty (CFS >4) was associated with significantly increased mortality both in elective surgery patients (7% vs 12%; p = 0.01), in acute surgery (7% vs 12%; p = 0.02).Conclusions: VIPs admitted to ICU after elective surgery evidenced favorable outcome over patients after acute surgery even after correction for relevant confounders. Frailty might be used to guide clinicians in risk stratification in both patients admitted after elective and acute surgery.
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| 31. |
- Koubarakis, M., et al.
(author)
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From copernicus big data to extreme earth analytics
- 2019
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In: Advances in Database Technology - EDBT. - : OpenProceedings. - 9783893180813 ; , s. 690-693
-
Conference paper (peer-reviewed)abstract
- Copernicus is the European programme for monitoring the Earth. It consists of a set of systems that collect data from satellites and in-situ sensors, process this data and provide users with reliable and up-to-date information on a range of environmental and security issues. The data and information processed and disseminated puts Copernicus at the forefront of the big data paradigm, giving rise to all relevant challenges, the so-called 5 Vs: volume, velocity, variety, veracity and value. In this short paper, we discuss the challenges of extracting information and knowledge from huge archives of Copernicus data. We propose to achieve this by scale-out distributed deep learning techniques that run on very big clusters offering virtual machines and GPUs. We also discuss the challenges of achieving scalability in the management of the extreme volumes of information and knowledge extracted from Copernicus data. The envisioned scientific and technical work will be carried out in the context of the H2020 project ExtremeEarth which starts in January 2019.
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| 32. |
- Sanín, M. J., et al.
(author)
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Volcanic events coincide with plant dispersal across the Northern Andes
- 2022
-
In: Global and Planetary Change. - : Elsevier BV. - 0921-8181. ; 210
-
Journal article (peer-reviewed)abstract
- Biological dispersal is increasingly seen as a primary driver of speciation across the tropical Andes. Similarly, growing evidence suggests that the Northern Andes cordilleras formed as disconnected segments, at least until the late Miocene. For montane species, this discontinuity can hinder dispersal to the different mountain segments. Hence, understanding which processes involved in mountain formation are related to species capacity to disperse between mountains is crucial to understanding Andean biogeography. Volcanic eruptions are known to affect biodiversity in different ways, but their effects on species connectivity through the creation of topographic growth remains largely unknown. Species that are distributed in the different geographic units of the Andes can be informative with respect to how and when the different mountains have formed. The wax palms, genus Ceroxylon, comprise 13 strictly Andean species of which three species complexes are widely distributed in the tropical Andes, inhabiting cloud forests at elevations of 1400–3500 m. We sequenced 129 individuals of all but one described species using target sequence capture to reconstruct the phylogenetic history of Ceroxylon. We inferred chronograms using secondary calibrations and demographic modeling, which along with ancestral area reconstructions, allowed us to estimate the relative contributions of dispersal and speciation in the diversification history of Ceroxylon. Geological samples of ignimbritic rocks record a Plio-Pleistocene volcanic eruption of great magnitude that connected the three Colombian cordilleras by increasing topographic growth where a former lowland pass disconnected the northern mountain segments. The timing of this topographic change coincides with an increase in dispersal events to the Western and Central Cordilleras of Colombia from adjacent Andean cordilleras (i.e. the Andes outside of Colombia). Taken together, we determine that local topographic growth resulting from volcanic eruptions played a key role in augmenting mountain chain connectivity by uplift and valley filling, which favored dispersal throughout the Northern Andes. We can spatially and temporally link a biogeographical distribution pattern to a traceable geological event. © 2022 Elsevier B.V.
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| 33. |
- Zhang, L, et al.
(author)
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An MPER antibody neutralizes HIV-1 using germline features shared among donors
- 2019
-
In: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 5389-
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Journal article (peer-reviewed)abstract
- The membrane-proximal external region (MPER) of HIV-1 envelope glycoprotein (Env) can be targeted by neutralizing antibodies of exceptional breadth. MPER antibodies usually have long, hydrophobic CDRH3s, lack activity as inferred germline precursors, are often from the minor IgG3 subclass, and some are polyreactive, such as 4E10. Here we describe an MPER broadly neutralizing antibody from the major IgG1 subclass, PGZL1, which shares germline V/D-region genes with 4E10, has a shorter CDRH3, and is less polyreactive. A recombinant sublineage variant pan-neutralizes a 130-isolate panel at 1.4 μg/ml (IC50). Notably, a germline revertant with mature CDR3s neutralizes 12% of viruses and still binds MPER after DJ reversion. Crystal structures of lipid-bound PGZL1 variants and cryo-EM reconstruction of an Env-PGZL1 complex reveal how these antibodies recognize MPER and viral membrane. Discovery of common genetic and structural elements among MPER antibodies from different patients suggests that such antibodies could be elicited using carefully designed immunogens.
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| 34. |
- Donnarumma, I., et al.
(author)
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Multiwavelength Observations of 3C 454.3. II. The AGILE 2007 December Campaign
- 2009
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In: Astrophysical Journal Letters. - 2041-8205. ; 707:2, s. 1115-1123
-
Journal article (peer-reviewed)abstract
- We report on the second Astrorivelatore Gamma a Immagini Leggero (AGILE) multiwavelength campaign of the blazar 3C 454.3 during the first half of 2007 December. This campaign involved AGILE, Spitzer, Swift, Suzaku, the Whole Earth Blazar Telescope (WEBT) consortium, the Rapid Eye Mount (REM), and the Multicolor Imaging Telescopes for Survey and Monstrous Explosions (MITSuME) telescopes, offering a broadband coverage that allowed for a simultaneous sampling of the synchrotron and inverse Compton (IC) emissions. The two-week AGILE monitoring was accompanied by radio to optical monitoring by WEBT and REM, and by sparse observations in mid-infrared and soft/ hard X-ray energy bands performed by means of Target of Opportunity observations by Spitzer, Swift, and Suzaku, respectively. The source was detected with an average flux of similar to 250 x 10(-8) photons cm(-2) s(-1) above 100 MeV, typical of its flaring states. The simultaneous optical and gamma-ray monitoring allowed us to study the time lag associated with the variability in the two energy bands, resulting in a possible <= one-day delay of the gamma-ray emission with respect to the optical one. From the simultaneous optical and gamma-ray fast flare detected on December 12, we can constrain the delay between the gamma-ray and optical emissions within 12 hr. Moreover, we obtain three spectral energy distributions (SEDs) with simultaneous data for 2007 December 5, 13, and 15, characterized by the widest multifrequency coverage. We found that a model with an external Compton on seed photons by a standard disk and reprocessed by the broad-line regions does not describe in a satisfactory way the SEDs of 2007 December 5, 13, and 15. An additional contribution, possibly from the hot corona with T = 10(6) K surrounding the jet, is required to account simultaneously for the softness of the synchrotron and the hardness of the IC emissions during those epochs.
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| 35. |
- Fonseca, R. D., et al.
(author)
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Fabrication of zinc oxide nanowires/polymer composites by two-photon polymerization
- 2014
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In: Journal of Polymer Science Part B. - : Wiley. - 0887-6266 .- 1099-0488. ; 52:4, s. 333-337
-
Journal article (peer-reviewed)abstract
- We present an approach to fabricate ZnO nanowires/polymer composite into three-dimensional microstructures, based on two-photon polymerization direct laser writing, a fabrication method that allows submicrometric spatial resolution. The structural integrity of the structures was inferred by scanning electron microscopy, while the presence and distribution of ZnO nanowires was investigated by energy dispersive X-ray, Raman spectroscopy, and X-ray diffraction. The optical properties of the produced composite microstructures were verified by imaging the characteristic ZnO emission using a fluorescence microscope. Hence, such approach can be used to develop composite microstructures containing ZnO nanowires aiming at technological applications.
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| 36. |
- Hodge, Simon, et al.
(author)
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Design and Planning of a Transdisciplinary Investigation into Farmland Pollinators : Rationale, Co-Design, and Lessons Learned
- 2022
-
In: Sustainability (Switzerland). - : MDPI AG. - 2071-1050. ; 14:17
-
Journal article (peer-reviewed)abstract
- To provide a complete portrayal of the multiple factors negatively impacting insects in agricultural landscapes it is necessary to assess the concurrent incidence, magnitude, and interactions among multiple stressors over substantial biogeographical scales. Trans-national ecological field investigations with wide-ranging stakeholders typically encounter numerous challenges during the design planning stages, not least that the scientific soundness of a spatially replicated study design must account for the substantial geographic and climatic variation among distant sites. ‘PoshBee’ (Pan-European assessment, monitoring, and mitigation of Stressors on the Health of Bees) is a multi-partner transdisciplinary agroecological project established to investigate the suite of stressors typically encountered by pollinating insects in European agricultural landscapes. To do this, PoshBee established a network of 128 study sites across eight European countries and collected over 50 measurements and samples relating to the nutritional, toxicological, pathogenic, and landscape components of the bees’ environment. This paper describes the development process, rationale, and end-result of each aspect of the of the PoshBee field investigation. We describe the main issues and challenges encountered during the design stages and highlight a number of actions or processes that may benefit other multi-partner research consortia planning similar large-scale studies. It was soon identified that in a multi-component study design process, the development of interaction and communication networks involving all collaborators and stakeholders requires considerable time and resources. It was also necessary at each planning stage to be mindful of the needs and objectives of all stakeholders and partners, and further challenges inevitably arose when practical limitations, such as time restrictions and labour constraints, were superimposed upon prototype study designs. To promote clarity for all stakeholders, for each sub-component of the study, there should be a clear record of the rationale and reasoning that outlines how the final design transpired, what compromises were made, and how the requirements of different stakeholders were accomplished. Ultimately, multi-national agroecological field studies such as PoshBee benefit greatly from the involvement of diverse stakeholders and partners, ranging from field ecologists, project managers, policy legislators, mathematical modelers, and farmer organisations. While the execution of the study highlighted the advantages and benefits of large-scale transdisciplinary projects, the long planning period emphasized the need to formally describe a design framework that could facilitate the design process of future multi-partner collaborations.
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| 37. |
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| 38. |
- Neudecker, Denise, et al.
(author)
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Templates of expected measurement uncertainties
- 2023
-
In: EPJ NUCLEAR SCIENCES & TECHNOLOGIES. - : EDP Sciences. - 2491-9292. ; 9
-
Journal article (peer-reviewed)abstract
- The covariance committee of CSEWG (Cross Section Evaluation Working Group) established templates of expected measurement uncertainties for neutron-induced total, (n,gamma), neutron-induced charged-particle, and (n,xn) reaction cross sections as well as prompt fission neutron spectra, average prompt and total fission neutron multiplicities, and fission yields. Templates provide a list of what uncertainty sources are expected for each measurement type and observable, and suggest typical ranges of these uncertainties and correlations based on a survey of experimental data, associated literature, and feedback from experimenters. Information needed to faithfully include the experimental data in the nuclear-data evaluation process is also provided. These templates could assist (a) experimenters and EXFOR compilers in delivering more complete uncertainties and measurement information relevant for evaluations of new experimental data, and (b) evaluators in achieving a more comprehensive uncertainty quantification for evaluation purposes. This effort might ultimately lead to more realistic evaluated covariances for nuclear-data applications. In this topical issue, we cover the templates coming out of this CSEWG effort-typically, one observable per paper. This paper here prefaces this topical issue by introducing the concept and mathematical framework of templates, discussing potential use cases, and giving an example of how they can be applied (estimating missing experimental uncertainties of 235U(n,f) average prompt fission neutron multiplicities), and their impact on nuclear-data evaluations.
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| 39. |
- Pellizzoni, A., et al.
(author)
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Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE
- 2010
-
In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 327:5966, s. 663-665
-
Journal article (peer-reviewed)abstract
- Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.
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| 40. |
- Stjernberg, Ann-Christine Engvall, et al.
(author)
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Low concentrations of near-surface ozone in Siberia
- 2012
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In: Tellus. Series B, Chemical and physical meteorology. - : Stockholm University Press. - 0280-6509 .- 1600-0889. ; 64, s. 1-13
-
Journal article (peer-reviewed)abstract
- Siberia with its large area covered with boreal forests, wetlands and tundra is believed to be an important sink for ozone via dry deposition and reactions with biogenic volatile organic compounds (BVOCs) emitted by the forests. To study the importance of deposition of ozone in Siberia, we analyse measurements of ozone mixing ratios taken along the Trans-Siberian railway by train, air-borne measurements and point measurements at the Zotino station. For all data, we ran the Lagrangian particle dispersion model FLEXPART in backward mode for 20 d, which yields the so-called potential emission sensitivity (PES) fields. These fields give a quantitative measure of where and how strongly the sampled air masses have been in contact with the surface and hence possible influenced by surface fluxes. These fields are further statistically analysed to identify source and sink regions that are influencing the observed ozone. Results show that the source regions for the surface ozone in Siberia are located at lower latitudes: the regions around the Mediterranean Sea, the Middle East, Kazakhstan and China. Low ozone mixing ratios are associated to transport from North West Russia, the Arctic region, and the Pacific Ocean. By calculating PES values for both a passive tracer without consideration of removal processes and for an ozone-like tracer where dry deposition processes are included, we are able to quantify the ozone loss occurring en route to the receptor. Strong correlations between low ozone concentrations and the spatially integrated footprints from FLEXPART, especially during the period summer to autumn, indicate the importance of the Siberian forests as a sink for tropospheric ozone.
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| 41. |
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| 42. |
- Wang, Qisi, et al.
(author)
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Magnon interactions in a moderately correlated Mott insulator
- 2024
-
In: Nature Communications. - : Springer Nature. - 2041-1723. ; 15:1
-
Journal article (peer-reviewed)abstract
- Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to experimentally gauge the strength and importance of quantum fluctuations. Here we provide a resonant inelastic x-ray scattering study of magnon excitations in Mott insulating cuprates. From the thin film of SrCuO2, single- and bi-magnon dispersions are derived. Using an effective Heisenberg Hamiltonian generated from the Hubbard model, we show that the single-magnon dispersion is only described satisfactorily when including significant quantum corrections stemming from magnon-magnon interactions. Comparative results on La2CuO4 indicate that quantum fluctuations are much stronger in SrCuO2 suggesting closer proximity to a magnetic quantum critical point. Monte Carlo calculations reveal that other magnetic orders may compete with the antiferromagnetic Néel order as the ground state. Our results indicate that SrCuO2—due to strong quantum fluctuations—is a unique starting point for the exploration of novel magnetic ground states.
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