| 1. |
- Abelev, Betty, et al.
(författare)
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Long-range angular correlations on the near and away side in p-Pb collisions at root S-NN=5.02 TeV
- 2013
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Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 719:1-3, s. 29-41
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Tidskriftsartikel (refereegranskat)abstract
- Angular correlations between charged trigger and associated particles are measured by the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV for transverse momentum ranges within 0.5 < P-T,P-assoc < P-T,P-trig < 4 GeV/c. The correlations are measured over two units of pseudorapidity and full azimuthal angle in different intervals of event multiplicity, and expressed as associated yield per trigger particle. Two long-range ridge-like structures, one on the near side and one on the away side, are observed when the per-trigger yield obtained in low-multiplicity events is subtracted from the one in high-multiplicity events. The excess on the near-side is qualitatively similar to that recently reported by the CMS Collaboration, while the excess on the away-side is reported for the first time. The two-ridge structure projected onto azimuthal angle is quantified with the second and third Fourier coefficients as well as by near-side and away-side yields and widths. The yields on the near side and on the away side are equal within the uncertainties for all studied event multiplicity and p(T) bins, and the widths show no significant evolution with event multiplicity or p(T). These findings suggest that the near-side ridge is accompanied by an essentially identical away-side ridge. (c) 2013 CERN. Published by Elsevier B.V. All rights reserved.
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| 2. |
- Abelev, Betty, et al.
(författare)
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Measurement of prompt J/psi and beauty hadron production cross sections at mid-rapidity in pp collisions at root s=7 TeV
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :11
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Tidskriftsartikel (refereegranskat)abstract
- The ALICE experiment at the LHC has studied J/psi production at mid-rapidity in pp collisions at root s = 7 TeV through its electron pair decay on a data sample corresponding to an integrated luminosity L-int = 5.6 nb(-1). The fraction of J/psi from the decay of long-lived beauty hadrons was determined for J/psi candidates with transverse momentum p(t) > 1,3 GeV/c and rapidity vertical bar y vertical bar < 0.9. The cross section for prompt J/psi mesons, i.e. directly produced J/psi and prompt decays of heavier charmonium states such as the psi(2S) and chi(c) resonances, is sigma(prompt J/psi) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 8.3 +/- 0.8(stat.) +/- 1.1 (syst.)(-1.4)(+1.5) (syst. pol.) mu b. The cross section for the production of b-hadrons decaying to J/psi with p(t) > 1.3 GeV/c and vertical bar y vertical bar < 0.9 is a sigma(J/psi <- hB) (p(t) > 1.3 GeV/c, vertical bar y vertical bar < 0.9) = 1.46 +/- 0.38 (stat.)(-0.32)(+0.26) (syst.) mu b. The results are compared to QCD model predictions. The shape of the p(t) and y distributions of b-quarks predicted by perturbative QCD model calculations are used to extrapolate the measured cross section to derive the b (b) over bar pair total cross section and d sigma/dy at mid-rapidity.
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| 3. |
- Abelev, Betty, et al.
(författare)
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Underlying Event measurements in pp collisions at root s=0.9 and 7 TeV with the ALICE experiment at the LHC
- 2012
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; :7
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Tidskriftsartikel (refereegranskat)abstract
- We present measurements of Underlying Event observables in pp collisions at root s = 0 : 9 and 7 TeV. The analysis is performed as a function of the highest charged-particle transverse momentum p(T),L-T in the event. Different regions are defined with respect to the azimuthal direction of the leading (highest transverse momentum) track: Toward, Transverse and Away. The Toward and Away regions collect the fragmentation products of the hardest partonic interaction. The Transverse region is expected to be most sensitive to the Underlying Event activity. The study is performed with charged particles above three different p(T) thresholds: 0.15, 0.5 and 1.0 GeV/c. In the Transverse region we observe an increase in the multiplicity of a factor 2-3 between the lower and higher collision energies, depending on the track p(T) threshold considered. Data are compared to PYTHIA 6.4, PYTHIA 8.1 and PHOJET. On average, all models considered underestimate the multiplicity and summed p(T) in the Transverse region by about 10-30%.
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| 4. |
- Graf, Alexander, et al.
(författare)
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Altered energy partitioning across terrestrial ecosystems in the European drought year 2018 : Energy partitioning in the drought 2018
- 2020
-
Ingår i: Philosophical Transactions of the Royal Society B: Biological Sciences. - : The Royal Society. - 0962-8436 .- 1471-2970. ; 375:1810
-
Tidskriftsartikel (refereegranskat)abstract
- Drought and heat events, such as the 2018 European drought, interact with the exchange of energy between the land surface and the atmosphere, potentially affecting albedo, sensible and latent heat fluxes, as well as CO 2 exchange. Each of these quantities may aggravate or mitigate the drought, heat, their side effects on productivity, water scarcity and global warming. We used measurements of 56 eddy covariance sites across Europe to examine the response of fluxes to extreme drought prevailing most of the year 2018 and how the response differed across various ecosystem types (forests, grasslands, croplands and peatlands). Each component of the surface radiation and energy balance observed in 2018 was compared to available data per site during a reference period 2004-2017. Based on anomalies in precipitation and reference evapotranspiration, we classified 46 sites as drought affected. These received on average 9% more solar radiation and released 32% more sensible heat to the atmosphere compared to the mean of the reference period. In general, drought decreased net CO 2 uptake by 17.8%, but did not significantly change net evapotranspiration. The response of these fluxes differed characteristically between ecosystems; in particular, the general increase in the evaporative index was strongest in peatlands and weakest in croplands. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.
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| 5. |
- Wiecher, Carsten, et al.
(författare)
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Model-based analysis and specification of functional requirements and tests for complex automotive systems
- 2024
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Ingår i: Systems Engineering. - : John Wiley & Sons. - 1098-1241 .- 1520-6858.
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Tidskriftsartikel (refereegranskat)abstract
- The specification of requirements and tests are crucial activities in automotive development projects. However, due to the increasing complexity of automotive systems, practitioners fail to specify requirements and tests for distributed and evolving systems with complex interactions when following traditional development processes. To address this research gap, we propose a technique that starts with the early identification of validation concerns from a stakeholder perspective, which we use to systematically design tests that drive a scenario-based modeling and analysis of system requirements. To ensure complete and consistent requirements and test specifications in a form that is required in automotive development projects, we develop a Model-Based Systems Engineering (MBSE) methodology. This methodology supports system architects and test designers in the collaborative application of our technique and in maintaining a central system model, in order to automatically derive the required specifications. We evaluate our methodology by applying it at KOSTAL (Tier1 supplier) and within student projects as part of the masters program Embedded Systems Engineering. Our study corroborates that our methodology is applicable and improves existing requirements and test specification processes by supporting the integrated and stakeholder-focused modeling of product and validation systems, where the early definition of stakeholder and validation concerns fosters a problem-oriented, iterative and test-driven requirements modeling. © 2024 Wiley Periodicals, Inc.
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| 6. |
- Bibic, Adnan, et al.
(författare)
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Measurement of vascular water transport in human subjects using time-resolved pulsed arterial spin labelling.
- 2015
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Ingår i: NMR in Biomedicine. - : Wiley. - 0952-3480. ; 28:8, s. 1059-1068
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Tidskriftsartikel (refereegranskat)abstract
- Most approaches to arterial spin labelling (ASL) data analysis aim to provide a quantitative measure of the cerebral blood flow (CBF). This study, however, focuses on the measurement of the transfer time of blood water through the capillaries to the parenchyma (referred to as the capillary transfer time, CTT) as an alternative parameter to characterise the haemodynamics of the system. The method employed is based on a non-compartmental model, and no measurements need to be added to a common time-resolved ASL experiment. Brownian motion of labelled spins in a potential was described by a one-dimensional general Langevin equation as the starting point, and as a Fokker-Planck differential equation for the averaged distribution of labelled spins at the end point, which takes into account the effects of flow and dispersion of labelled water by the pseudorandom nature of the microvasculature and the transcapillary permeability. Multi-inversion time (multi-TI) ASL data were acquired in 14 healthy subjects on two occasions in a test-retest design, using a pulsed ASL sequence and three-dimensional gradient and spin echo (3D-GRASE) readout. Based on an error analysis to predict the size of a region of interest (ROI) required to obtain reasonably precise parameter estimates, data were analysed in two relatively large ROIs, i.e. the occipital lobe (OC) and the insular cortex (IC). The average values of CTT in OC were 260 ± 60 ms in the first experiment and 270 ± 60 ms in the second experiment. The corresponding IC values were 460 ± 130 ms and 420 ± 139 ms, respectively. Information related to the water transfer time may be important for diagnostics and follow-up of cerebral conditions or diseases characterised by a disrupted blood-brain barrier or disturbed capillary blood flow. Copyright © 2015 John Wiley & Sons, Ltd.
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| 7. |
- Bonnemeier, Hendrik, et al.
(författare)
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Automated continuous chest compression for in-hospital cardiopulmonary resuscitation of patients with pulseless electrical activity: A report of five cases
- 2009
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Ingår i: International Journal of Cardiology. - : Elsevier BV. - 0167-5273. ; 136:2, s. 39-50
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Tidskriftsartikel (refereegranskat)abstract
- Of patients with in-hospital cardiac arrest, those with pulseless electrical activity ( PEA) have the worst outcome. Especially in these patients effective chest compressions according to the guidelines may be the key strategy to improve survival. Recently, a novel automatic mechanical chest compression device (LUCAS-CPR) has been shown to ensure effective continuous compressions without interruption during transport, diagnostic procedures and in the catheter laboratory, and may thus significantly improve outcome after resuscitation of in-hospital cardiac arrest. We report here on the first five well documented cases of in-hospital resuscitation of PEA using the LUCAS-CPR compression device. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
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| 8. |
- Bonnemeier, Hendrik, et al.
(författare)
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Continuous mechanical chest compression during in-hospital cardiopulmonary resuscitation of patients with pulseless electrical activity
- 2011
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Ingår i: Resuscitation. - : Elsevier BV. - 1873-1570 .- 0300-9572. ; 82:2, s. 155-159
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Tidskriftsartikel (refereegranskat)abstract
- Survival after in-hospital pulseless electrical activity (PEA) cardiac arrest is poor and has not changed during the last 10 years. Effective chest compressions may improve survival after PEA. We investigated whether a mechanical device (LUCAS (TM)-CPR) can ensure chest compressions during cardiac arrest according to guidelines and without interruption during transport, diagnostic procedures and in the catheter laboratory. Methods: We studied mechanical chest compression in 28 patients with PEA (pulmonary embolism (PE) n = 14; cardiogenic shock/acute myocardial infarction; n=9; severe hyperkalemia; n=2; sustained ventricular arrhythmias/electrical storm; n=3) in a university hospital setting. Results: During or immediately after CPR, 21 patients underwent coronary angiography and or pulmonary angiography. Successful return of a spontaneous circulation (ROSC) was achieved in 27 out of the 28 patients. Ten patients died within the first hour and three patients died within 2411 after CPR. A total of 14 patients survived and were discharged from hospital (13 without significant neurological deficit). Interestingly, six patients with PE did not have thrombolytic therapy due to contraindications. CT-angiography findings in these patients showed fragmentation of the thrombus suggesting thrombus breakdown as an additional effect of mechanical chest compressions. No patients exhibited any life-threatening device-related complications. Conclusion: Continuous chest compression with an automatic mechanical device is feasible, safe, and might improve outcomes after in-hospital-resuscitation of PEA. Patients with PE may benefit from effective continuous chest compression, probably due to thrombus fragmentation and increased pulmonary artery blood flow. (C) 2010 Elsevier Ireland Ltd. All rights reserved.
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| 9. |
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| 10. |
- Borris, Matthias, et al.
(författare)
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Source-Based Modeling Of Urban Stormwater Quality Response to the Selected Scenarios Combining Future Changes in Climate and Socio-Economic Factors
- 2016
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Ingår i: Environmental Management. - : Springer Science and Business Media LLC. - 0364-152X .- 1432-1009. ; 58:2, s. 223-237
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Tidskriftsartikel (refereegranskat)abstract
- The assessment of future trends in urban stormwater quality should be most helpful for ensuring the effectiveness of the existing stormwater quality infrastructure in the future and mitigating the associated impacts on receiving waters. Combined effects of expected changes in climate and socio-economic factors on stormwater quality were examined in two urban test catchments by applying a source-based computer model (WinSLAMM) for TSS and three heavy metals (copper, lead, and zinc) for various future scenarios. Generally, both catchments showed similar responses to the future scenarios and pollutant loads were generally more sensitive to changes in socio-economic factors (i.e., increasing traffic intensities, growth and intensification of the individual land-uses) than in the climate. Specifically, for the selected Intermediate socio-economic scenario and two climate change scenarios (RSP = 2.6 and 8.5), the TSS loads from both catchments increased by about 10 % on average, but when applying the Intermediate climate change scenario (RCP = 4.5) for two SSPs, the Sustainability and Security scenarios (SSP1 and SSP3), the TSS loads increased on average by 70 %. Furthermore, it was observed that well-designed and maintained stormwater treatment facilities targeting local pollution hotspots exhibited the potential to significantly improve stormwater quality, however, at potentially high costs. In fact, it was possible to reduce pollutant loads from both catchments under the future Sustainability scenario (on average, e.g., TSS were reduced by 20 %), compared to the current conditions. The methodology developed in this study was found useful for planning climate change adaptation strategies in the context of local conditions.
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| 11. |
- Dreha-Kulaczewski, Steffi, et al.
(författare)
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Folate receptor α deficiency : Myelin‐sensitive MRI as a reliable biomarker to monitor the efficacy and long‐term outcome of a new therapeutic approach
-
Ingår i: Journal of Inherited Metabolic Disease. - 0141-8955. ; , s. 1-17
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Tidskriftsartikel (refereegranskat)abstract
- Cerebral folate transport deficiency, caused by a genetic defect in folate recep-torα, is a devastating neurometabolic disorder that, if untreated, leads to epi-leptic encephalopathy, psychomotor decline and hypomyelination. Currently,there are limited data on effective dosage and duration of treatment, thoughearly diagnosis and therapy with folinic acid appears critical. The aim of thislong-term study was to identify new therapeutic approaches and novel bio-markers for assessing efficacy, focusing on myelin-sensitive MRI. Clinical, bio-chemical, structural and quantitative MRI parameters of seven patients withgenetically confirmed folate receptorαdeficiency were acquired over 13 years.Multimodal MRI approaches comprised MR-spectroscopy (MRS), magnetiza-tion transfer (MTI) and diffusion tensor imaging (DTI) sequences. Patientsstarted oral treatment immediately following diagnosis or in an interval of upto 2.5 years. Escalation to intravenous and intrathecal administration was per-formed in the absence of effects. Five patients improved, one with a presymp-tomatic start of therapy remained symptom-free, and one with inconsistenttreatment deteriorated. While CSF 5-methyltetrahydrofolate and MRS parame-ters normalized immediately after therapy initiation, myelin-sensitive MTI andDTI measures correlated with gradual clinical improvement and ongoing mye-lination under therapy. Early initiation of treatment at sufficient doses, consid-ering early intrathecal applications, is critical for favorable outcome. Themajority of patients showed clinical improvements that correlated best withMTI parameters, allowing individualized monitoring of myelination recovery.Presymptomatic therapy seems to ensure normal development and warrantsnewborn screening. Furthermore, the quantitative parameters of myelin-sensitive MRI for therapy assessments can now be used for hypomyelinationdisorders in general.
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| 12. |
- Gräbner, Dietmar, et al.
(författare)
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Classification of customer Reviews based on Sentiment Analysis
- 2012
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Ingår i: Information and Communication Technologies in Tourism 2012. - Vienna : Springer. - 9783709111413 ; , s. 460-470
-
Konferensbidrag (refereegranskat)abstract
- In this paper we propose a system that performs the classification of customer reviews of hotels by means of a sentiment analysis. We elaborate on a process to extract a domainspecific lexicon of semantically relevant words based on a given corpus (Scharl et al., 2003; Pak & Paroubek, 2010). The resulting lexicon backs the sentiment analysis for generating a classification of the reviews. The evaluation of the classification on test data shows that the proposed system performs better compared to a predefined baseline: if a customer review is classified as good or bad the classification is correct with a probability of about 90%.
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| 13. |
- Horn, Matthias, et al.
(författare)
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A*-based construction of decision diagrams for a prize-collecting scheduling problem
- 2021
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Ingår i: Computers & Operations Research. - : Elsevier. - 0305-0548 .- 1873-765X. ; 126
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Tidskriftsartikel (refereegranskat)abstract
- Decision diagrams (DDs) have proven to be useful tools in combinatorial optimization. Relaxed DDs represent discrete relaxations of problems, can encode essential structural information in a compact form, and may yield strong dual bounds. We propose a novel construction scheme for relaxed multi-valued DDs for a scheduling problem in which a subset of elements has to be selected from a ground set and the selected elements need to be sequenced. The proposed construction scheme builds upon A search guided by a fast-to-calculate problem-specific dual bound heuristic. In contrast to traditional DD compilation methods, the new approach does not rely on a correspondence of DD layers to decision variables. For the considered kind of problem, this implies that multiple nodes representing the same state at different layers can be avoided, and consequently also many redundant isomorphic substructures. For keeping the relaxed DD compact, a new mechanism for merging nodes in a layer-independent way is suggested. For our prize-collecting job sequencing problem, experimental results show that the DDs from our A -based approach provide substantially better bounds while frequently being an order-ofmagnitude smaller than DDs obtained from traditional compilation methods, given about the same time. To obtain a heuristic solution and a corresponding lower bound, we further propose to construct a restricted DD based on the relaxed one, thereby substantially exploiting already gained information. This approach outperforms a standalone restricted DD construction, basic constraint programming and mixed integer linear programming approaches, and a variable neighborhood search in terms of solution quality on most of our benchmark instances.
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| 14. |
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| 15. |
- Jennbert, Kristina, et al.
(författare)
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Animal mouthpieces for human properties and indentity - A Scandinavian perspective
- 2010
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Ingår i: Bestial Mirrors. Using animals to construct human identities in Medieval Europe. - 9783200018952 ; 03, s. 39-45
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Peoples' relations to animals and their various roles took many different expressions in the pre-Christian era. In certain contexts animals had practical functions, but others they also had symbolic values. Domsticated animals were a kind of life style metaphors in grave rituals. Wild animals and transformation between humans and animals in pictorial images signified social identity. The archaeological analysis of pre-Christian use of animals, and the interpretation of relations between humans and animals give a historical background to the later textbased Old Norse mythology.
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| 16. |
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| 17. |
- Kolberg, Matthias, et al.
(författare)
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A new tyrosyl radical on Phe208 as ligand to the diiron center in Escherichia coli ribonucleotide reductase, mutant R2-Y122H. Combined x-ray diffraction and EPR/ENDOR studies.
- 2005
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Ingår i: J Biol Chem. - 0021-9258. ; 280:12, s. 11233-11246
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The R2 protein subunit of class I ribonucleotide reductase (RNR) belongs to a structurally related family of oxygen bridged diiron proteins. In wild-type R2 of Escherichia coli, reductive cleavage of molecular oxygen by the diferrous iron center generates a radical on a nearby tyrosine residue (Tyr122), which is essential for the enzymatic activity of RNR, converting ribonucleotides into deoxyribonucleotides. In this work, we characterize the mutant E. coli protein R2-Y122H, where the radical site is substituted with a histidine residue. The x-ray structure verifies the mutation. R2-Y122H contains a novel stable paramagnetic center which we name H, and which we have previously proposed to be a diferric iron center with a strongly coupled radical, Fe(III)Fe(III)R.. Here we report a detailed characterization of center H, using 1H/2H -14N/15N- and 57Fe-ENDOR in comparison with the Fe(III)Fe(IV) intermediate X observed in the iron reconstitution reaction of R2. Specific deuterium labeling of phenylalanine residues reveals that the radical results from a phenylalanine. As Phe208 is the only phenylalanine in the ligand sphere of the iron site, and generation of a phenyl radical requires a very high oxidation potential, we propose that in Y122H residue Phe208 is hydroxylated, as observed earlier in another mutant (R2-Y122F/E238A), and further oxidized to a phenoxyl radical, which is coordinated to Fe1. This work demonstrates that small structural changes can redirect the reactivity of the diiron site, leading to oxygenation of a hydrocarbon, as observed in the structurally similar methane monoxygenase, and beyond, to formation of a stable iron-coordinated radical.
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| 18. |
- Krzywicka, Katarzyna, et al.
(författare)
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Decompressive surgery in cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia.
- 2023
-
Ingår i: European journal of neurology. - : Wiley. - 1468-1331 .- 1351-5101. ; 30:5, s. 1335-1345
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Tidskriftsartikel (refereegranskat)abstract
- Cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) is an adverse drug reaction occurring after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. CVST-VITT patients often present with large intracerebral haemorrhages and a high proportion undergoes decompressive surgery. Clinical characteristics, therapeutic management and outcomes of CVST-VITT patients who underwent decompressive surgery are described and predictors of in-hospital mortality in these patients are explored.Data from an ongoing international registry of patients who developed CVST within 28days of SARS-CoV-2 vaccination, reported between 29 March 2021 and 10 May 2022, were used. Definite, probable and possible VITT cases, as defined by Pavord et al. (N Engl J Med 2021; 385: 1680-1689), were included.Decompressive surgery was performed in 34/128 (27%) patients with CVST-VITT. In-hospital mortality was 22/34 (65%) in the surgical and 27/94 (29%) in the non-surgical group (p<0.001). In all surgical cases, the cause of death was brain herniation. The highest mortality rates were found amongst patients with preoperative coma (17/18, 94% vs. 4/14, 29% in the non-comatose; p<0.001) and bilaterally absent pupillary reflexes (7/7, 100% vs. 6/9, 67% with unilaterally reactive pupil, and 4/11, 36% with bilaterally reactive pupils; p=0.023). Postoperative imaging revealed worsening of index haemorrhagic lesion in 19 (70%) patients and new haemorrhagic lesions in 16 (59%) patients. At a median follow-up of 6months, 8/10 of surgical CVST-VITT who survived admission were functionally independent.Almost two-thirds of surgical CVST-VITT patients died during hospital admission. Preoperative coma and bilateral absence of pupillary responses were associated with higher mortality rates. Survivors often achieved functional independence.
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| 19. |
- Lindner, Thomas, et al.
(författare)
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Current state and guidance on arterial spin labeling perfusion MRI in clinical neuroimaging.
- 2023
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Ingår i: Magnetic Resonance in Medicine. - : John Wiley & Sons. - 0740-3194 .- 1522-2594. ; 89:5, s. 2024-2047
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Tidskriftsartikel (refereegranskat)abstract
- This article focuses on clinical applications of arterial spin labeling (ASL) and is part of a wider effort from the International Society for Magnetic Resonance in Medicine (ISMRM) Perfusion Study Group to update and expand on the recommendations provided in the 2015 ASL consensus paper. Although the 2015 consensus paper provided general guidelines for clinical applications of ASL MRI, there was a lack of guidance on disease-specific parameters. Since that time, the clinical availability and clinical demand for ASL MRI has increased. This position paper provides guidance on using ASL in specific clinical scenarios, including acute ischemic stroke and steno-occlusive disease, arteriovenous malformations and fistulas, brain tumors, neurodegenerative disease, seizures/epilepsy, and pediatric neuroradiology applications, focusing on disease-specific considerations for sequence optimization and interpretation. We present several neuroradiological applications in which ASL provides unique information essential for making the diagnosis. This guidance is intended for anyone interested in using ASL in a routine clinical setting (i.e., on a single-subject basis rather than in cohort studies) building on the previous ASL consensus review.
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| 20. |
- McGrath, Matthew J., et al.
(författare)
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The consolidated European synthesis of CO2 emissions and removals for the European Union and United Kingdom : 1990-2020
- 2023
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Ingår i: Earth System Science Data. - 1866-3508. ; 15:10, s. 4295-4370
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Tidskriftsartikel (refereegranskat)abstract
- Quantification of land surface-atmosphere fluxes of carbon dioxide (CO2) and their trends and uncertainties is essential for monitoring progress of the EU27+UK bloc as it strives to meet ambitious targets determined by both international agreements and internal regulation. This study provides a consolidated synthesis of fossil sources (CO2 fossil) and natural (including formally managed ecosystems) sources and sinks over land (CO2 land) using bottom-up (BU) and top-down (TD) approaches for the European Union and United Kingdom (EU27+UK), updating earlier syntheses (Petrescu et al., 2020, 2021). Given the wide scope of the work and the variety of approaches involved, this study aims to answer essential questions identified in the previous syntheses and understand the differences between datasets, particularly for poorly characterized fluxes from managed and unmanaged ecosystems. The work integrates updated emission inventory data, process-based model results, data-driven categorical model results, and inverse modeling estimates, extending the previous period 1990-2018 to the year 2020 to the extent possible. BU and TD products are compared with the European national greenhouse gas inventory (NGHGI) reported by parties including the year 2019 under the United Nations Framework Convention on Climate Change (UNFCCC). The uncertainties of the EU27+UK NGHGI were evaluated using the standard deviation reported by the EU member states following the guidelines of the Intergovernmental Panel on Climate Change (IPCC) and harmonized by gap-filling procedures. Variation in estimates produced with other methods, such as atmospheric inversion models (TD) or spatially disaggregated inventory datasets (BU), originate from within-model uncertainty related to parameterization as well as structural differences between models. By comparing the NGHGI with other approaches, key sources of differences between estimates arise primarily in activities. System boundaries and emission categories create differences in CO2 fossil datasets, while different land use definitions for reporting emissions from land use, land use change, and forestry (LULUCF) activities result in differences for CO2 land. The latter has important consequences for atmospheric inversions, leading to inversions reporting stronger sinks in vegetation and soils than are reported by the NGHGI. For CO2 fossil emissions, after harmonizing estimates based on common activities and selecting the most recent year available for all datasets, the UNFCCC NGHGI for the EU27+UK accounts for 926g±g13gTggCgyr-1, while eight other BU sources report a mean value of 948 [937,961]gTggCgyr-1 (25th, 75th percentiles). The sole top-down inversion of fossil emissions currently available accounts for 875gTggC in this same year, a value outside the uncertainty of both the NGHGI and bottom-up ensemble estimates and for which uncertainty estimates are not currently available. For the net CO2 land fluxes, during the most recent 5-year period including the NGHGI estimates, the NGHGI accounted for -91g±g32gTggCgyr-1, while six other BU approaches reported a mean sink of -62 [-117,-49]gTggCgyr-1, and a 15-member ensemble of dynamic global vegetation models (DGVMs) reported -69 [-152,-5]gTggCgyr-1. The 5-year mean of three TD regional ensembles combined with one non-ensemble inversion of -73gTggCgyr-1 has a slightly smaller spread (0th-100th percentiles of [-135,+45]gTggCgyr-1), and it was calculated after removing net land-atmosphere CO2 fluxes caused by lateral transport of carbon (crop trade, wood trade, river transport, and net uptake from inland water bodies), resulting in increased agreement with the NGHGI and bottom-up approaches. Results at the category level (Forest Land, Cropland, Grassland) generally show good agreement between the NGHGI and category-specific models, but results for DGVMs are mixed. Overall, for both CO2 fossil and net CO2 land fluxes, we find that current independent approaches are consistent with the NGHGI at the scale of the EU27+UK. We conclude that CO2 emissions from fossil sources have decreased over the past 30 years in the EU27+UK, while land fluxes are relatively stable: positive or negative trends larger (smaller) than 0.07 (-0.61)gTggCgyr-2 can be ruled out for the NGHGI. In addition, a gap on the order of 1000gTggCgyr-1 between CO2 fossil emissions and net CO2 uptake by the land exists regardless of the type of approach (NGHGI, TD, BU), falling well outside all available estimates of uncertainties. However, uncertainties in top-down approaches to estimate CO2 fossil emissions remain uncharacterized and are likely substantial, in addition to known uncertainties in top-down estimates of the land fluxes. The data used to plot the figures are available at 10.5281/zenodo.8148461 (McGrath et al., 2023).
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| 21. |
- Menkveld, Albert J., et al.
(författare)
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Nonstandard Errors
- 2024
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Ingår i: JOURNAL OF FINANCE. - : Wiley-Blackwell. - 0022-1082 .- 1540-6261. ; 79:3, s. 2339-2390
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Tidskriftsartikel (refereegranskat)abstract
- In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty-nonstandard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for more reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants.
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| 22. |
- Muster, Sina, et al.
(författare)
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PeRL : a circum-Arctic Permafrost Region Pond and Lake database
- 2017
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Ingår i: Earth System Science Data. - : Copernicus GmbH. - 1866-3508 .- 1866-3516. ; 9:1, s. 317-348
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Tidskriftsartikel (refereegranskat)abstract
- Ponds and lakes are abundant in Arctic permafrost lowlands. They play an important role in Arctic wetland ecosystems by regulating carbon, water, and energy fluxes and providing freshwater habitats. However, ponds, i. e., waterbodies with surface areas smaller than 1.0 x 10(4) m(2), have not been inventoried on global and regional scales. The Permafrost Region Pond and Lake (PeRL) database presents the results of a circum-Arctic effort to map ponds and lakes from modern (2002-2013) high-resolution aerial and satellite imagery with a resolution of 5m or better. The database also includes historical imagery from 1948 to 1965 with a resolution of 6m or better. PeRL includes 69 maps covering a wide range of environmental conditions from tundra to boreal regions and from continuous to discontinuous permafrost zones. Waterbody maps are linked to regional permafrost landscape maps which provide information on permafrost extent, ground ice volume, geology, and lithology. This paper describes waterbody classification and accuracy, and presents statistics of waterbody distribution for each site. Maps of permafrost landscapes in Alaska, Canada, and Russia are used to extrapolate waterbody statistics from the site level to regional landscape units. PeRL presents pond and lake estimates for a total area of 1.4 x 10(6) km(2) across the Arctic, about 17% of the Arctic lowland (<300ma. s.l.) land surface area. PeRL waterbodies with sizes of 1.0 x 10(6) m(2) down to 1.0 x 10(2) m(2) contributed up to 21% to the total water fraction. Waterbody density ranged from 1.0 x 10 to 9.4 x 10(1) km(-2). Ponds are the dominant waterbody type by number in all landscapes representing 45-99% of the total waterbody number. The implementation of PeRL size distributions in land surface models will greatly improve the investigation and projection of surface inundation and carbon fluxes in permafrost lowlands. Waterbody maps, study area boundaries, and maps of regional permafrost landscapes including detailed metadata are available at https://doi.pangaea.de/10.1594/PANGAEA.868349.
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| 23. |
- Papatheocharous, Efi, et al.
(författare)
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PaaSword: A Data Privacy and Context-aware Security Framework for Developing Secure Cloud Applications - Technical and Scientific Contributions
- 2017
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Ingår i: European Space Projects: Developments, Implementations and Impacts in a Changing World - Volume 1: EPS Porto 2017, Porto, Portugal. - : SCITEPRESS - Science and Technology Publications. - 9789897583117 ; , s. 3-27
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Most industries worldwide have entered a period of reaping the benefits and opportunities cloud offers. At the same time, many efforts are made to address engineering challenges for the secure development of cloud systems and software.With the majority of software engineering projects today relying on the cloud, the task to structure end-to-end secure-by-design cloud systems becomes challenging but at the same time mandatory. The PaaSword project has been commissioned to address security and data privacy in a holistic way by proposing a context-aware security-by-design framework to support software developers in constructing secure applications for the cloud. This chapter presents an overview of the PaaSword project results, including the scientific achievements as well as the description of the technical solution. The benefits offered by the framework are validated through two pilot implementations and conclusions are drawn based on the future research challenges which are discussed in a research agenda.
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| 24. |
- Peterhoff, David, et al.
(författare)
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Comparative Immunogenicity of COVID-19 Vaccines in a Population-Based Cohort Study with SARS-CoV-2-Infected and Uninfected Participants
- 2022
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Ingår i: Vaccines. - : MDPI AG. - 2076-393X. ; 10:2
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Tidskriftsartikel (refereegranskat)abstract
- To assess vaccine immunogenicity in non-infected and previously infected individuals in a real-world scenario, SARS-CoV-2 antibody responses were determined during follow-up 2 (April 2021) of the population-based Tirschenreuth COVID-19 cohort study comprising 3378 inhabitants of the Tirschenreuth county aged 14 years or older. Seronegative participants vaccinated once with Vaxzevria, Comirnaty, or Spikevax had median neutralizing antibody titers ranging from ID50 = 25 to 75. Individuals with two immunizations with Comirnaty or Spikevax had higher median ID50s (of 253 and 554, respectively). Regression analysis indicated that both increased age and increased time since vaccination independently decreased RBD binding and neutralizing antibody levels. Unvaccinated participants with detectable N-antibodies at baseline (June 2020) revealed a median ID50 of 72 at the April 2021 follow-up. Previously infected participants that received one dose of Vaxzevria or Comirnaty had median ID50 to 929 and 2502, respectively. Individuals with a second dose of Comirnaty given in a three-week interval after the first dose did not have higher median antibody levels than individuals with one dose. Prior infection also primed for high systemic IgA levels in response to one dose of Comirnaty that exceeded IgA levels observed after two doses of Comirnaty in previously uninfected participants. Neutralizing antibody levels targeting the spike protein of Beta and Delta variants were diminished compared to the wild type in vaccinated and infected participants.
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| 25. |
- Petrescu, Ana Maria Roxana, et al.
(författare)
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The consolidated European synthesis of CO2emissions and removals for the European Union and United Kingdom : 1990-2018
- 2021
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Ingår i: Earth System Science Data. - : Copernicus GmbH. - 1866-3508 .- 1866-3516. ; 13:5, s. 2363-2406
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Forskningsöversikt (refereegranskat)abstract
- Reliable quantification of the sources and sinks of atmospheric carbon dioxide (CO2), including that of their trends and uncertainties, is essential to monitoring the progress in mitigating anthropogenic emissions under the Kyoto Protocol and the Paris Agreement. This study provides a consolidated synthesis of estimates for all anthropogenic and natural sources and sinks of CO2 for the European Union and UK (EU27 + UK), derived from a combination of state-of-the-art bottom-up (BU) and top-down (TD) data sources and models. Given the wide scope of the work and the variety of datasets involved, this study focuses on identifying essential questions which need to be answered to properly understand the differences between various datasets, in particular with regards to the less-well-characterized fluxes from managed ecosystems. The work integrates recent emission inventory data, process-based ecosystem model results, data-driven sector model results and inverse modeling estimates over the period 1990-2018. BU and TD products are compared with European national greenhouse gas inventories (NGHGIs) reported under the UNFCCC in 2019, aiming to assess and understand the differences between approaches. For the uncertainties in NGHGIs, we used the standard deviation obtained by varying parameters of inventory calculations, reported by the member states following the IPCC Guidelines. Variation in estimates produced with other methods, like atmospheric inversion models (TD) or spatially disaggregated inventory datasets (BU), arises from diverse sources including within-model uncertainty related to parameterization as well as structural differences between models. In comparing NGHGIs with other approaches, a key source of uncertainty is that related to different system boundaries and emission categories (CO2 fossil) and the use of different land use definitions for reporting emissions from land use, land use change and forestry (LULUCF) activities (CO2 land). At the EU27 + UK level, the NGHGI (2019) fossil CO2 emissions (including cement production) account for 2624 Tg CO2 in 2014 while all the other seven bottom-up sources are consistent with the NGHGIs and report a mean of 2588 (± 463 Tg CO2). The inversion reports 2700 Tg CO2 (± 480 Tg CO2), which is well in line with the national inventories. Over 2011-2015, the CO2 land sources and sinks from NGHGI estimates report-90 Tg C yr-1 ± 30 Tg C yr-1 while all other BU approaches report a mean sink of-98 Tg C yr-1 (± 362 Tg of C from dynamic global vegetation models only). For the TD model ensemble results, we observe a much larger spread for regional inversions (i.e., mean of 253 Tg C yr-1 ± 400 Tg C yr-1). This concludes that (a) current independent approaches are consistent with NGHGIs and (b) their uncertainty is too large to allow a verification because of model differences and probably also because of the definition of "CO2 flux"obtained from different approaches. The referenced datasets related to figures are visualized.
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| 26. |
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Sánchez Van Kammen, Mayte, et al.
(författare)
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Characteristics and Outcomes of Patients with Cerebral Venous Sinus Thrombosis in SARS-CoV-2 Vaccine-Induced Immune Thrombotic Thrombocytopenia
- 2021
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Ingår i: JAMA Neurology. - : American Medical Association. - 2168-6149 .- 2168-6157. ; 78:11, s. 1314-1323
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Tidskriftsartikel (refereegranskat)abstract
- Importance: Thrombosis with thrombocytopenia syndrome (TTS) has been reported after vaccination with the SARS-CoV-2 vaccines ChAdOx1 nCov-19 (Oxford-AstraZeneca) and Ad26.COV2.S (Janssen/Johnson & Johnson).Objective: To describe the clinical characteristics and outcome of patients with cerebral venous sinus thrombosis (CVST) after SARS-CoV-2 vaccination with and without TTS.Design, Setting, and Participants: This cohort study used data from an international registry of consecutive patients with CVST within 28 days of SARS-CoV-2 vaccination included between March 29 and June 18, 2021, from 81 hospitals in 19 countries. For reference, data from patients with CVST between 2015 and 2018 were derived from an existing international registry. Clinical characteristics and mortality rate were described for adults with (1) CVST in the setting of SARS-CoV-2 vaccine-induced immune thrombotic thrombocytopenia, (2) CVST after SARS-CoV-2 vaccination not fulling criteria for TTS, and (3) CVST unrelated to SARS-CoV-2 vaccination.Exposures: Patients were classified as having TTS if they had new-onset thrombocytopenia without recent exposure to heparin, in accordance with the Brighton Collaboration interim criteria.Main Outcomes and Measures: Clinical characteristics and mortality rate.Results: Of 116 patients with postvaccination CVST, 78 (67.2%) had TTS, of whom 76 had been vaccinated with ChAdOx1 nCov-19; 38 (32.8%) had no indication of TTS. The control group included 207 patients with CVST before the COVID-19 pandemic. A total of 63 of 78 (81%), 30 of 38 (79%), and 145 of 207 (70.0%) patients, respectively, were female, and the mean (SD) age was 45 (14), 55 (20), and 42 (16) years, respectively. Concomitant thromboembolism occurred in 25 of 70 patients (36%) in the TTS group, 2 of 35 (6%) in the no TTS group, and 10 of 206 (4.9%) in the control group, and in-hospital mortality rates were 47% (36 of 76; 95% CI, 37-58), 5% (2 of 37; 95% CI, 1-18), and 3.9% (8 of 207; 95% CI, 2.0-7.4), respectively. The mortality rate was 61% (14 of 23) among patients in the TTS group diagnosed before the condition garnered attention in the scientific community and 42% (22 of 53) among patients diagnosed later.Conclusions and Relevance: In this cohort study of patients with CVST, a distinct clinical profile and high mortality rate was observed in patients meeting criteria for TTS after SARS-CoV-2 vaccination..
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| 31. |
- Scutelnic, Adrian, et al.
(författare)
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Management of Cerebral Venous Thrombosis Due to Adenoviral COVID-19 Vaccination.
- 2022
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Ingår i: Annals of neurology. - : Wiley. - 1531-8249 .- 0364-5134. ; 92:4, s. 562-573
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Tidskriftsartikel (refereegranskat)abstract
- Cerebral venous thrombosis (CVT) caused by vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare adverse effect of adenovirus-based severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) vaccines. In March 2021, after autoimmune pathogenesis of VITT was discovered, treatment recommendations were developed. These comprised immunomodulation, non-heparin anticoagulants, and avoidance of platelet transfusion. The aim of this study was to evaluate adherence to these recommendations and its association with mortality.We used data from an international prospective registry of patients with CVT after the adenovirus-based SARS-CoV-2 vaccination. We analyzed possible, probable, or definite VITT-CVT cases included until January 18, 2022. Immunomodulation entailed administration of intravenous immunoglobulins and/or plasmapheresis.Ninety-nine patients with VITT-CVT from 71 hospitals in 17 countries were analyzed. Five of 38 (13%), 11 of 24 (46%), and 28 of 37 (76%) of the patients diagnosed in March, April, and from May onward, respectively, were treated in-line with VITT recommendations (p<0.001). Overall, treatment according to recommendations had no statistically significant influence on mortality (14/44 [32%] vs 29/55 [52%], adjusted odds ratio [OR]=0.43, 95% confidence interval [CI]=0.16-1.19). However, patients who received immunomodulation had lower mortality (19/65 [29%] vs 24/34 [70%], adjusted OR=0.19, 95% CI=0.06-0.58). Treatment with non-heparin anticoagulants instead of heparins was not associated with lower mortality (17/51 [33%] vs 13/35 [37%], adjusted OR=0.70, 95% CI=0.24-2.04). Mortality was also not significantly influenced by platelet transfusion (17/27 [63%] vs 26/72 [36%], adjusted OR=2.19, 95% CI=0.74-6.54).In patients with VITT-CVT, adherence to VITT treatment recommendations improved over time. Immunomodulation seems crucial for reducing mortality of VITT-CVT. ANN NEUROL 2022;92:562-573.
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| 32. |
- Steinmüller-Nethl, Doris, et al.
(författare)
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Strong binding of bioactive BMP-2 to nanocrystalline diamond by physisorption
- 2006
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Ingår i: Biomaterials. - : Elsevier BV. - 0142-9612. ; 27, s. 4547-4556
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Tidskriftsartikel (refereegranskat)abstract
- Nano-crystalline diamond (NCD)-coated surfaces were efficiently functionalized with bone morphogenetic protein-2 (BMP-2) by means of physisorption. Due to their randomly oriented texture, NCD-coated surfaces appear to bind complex molecules firmly. Applying various highly sensitive analytical methods, the interaction was found extremely stable. The strength of the experimentally measured adherence between BMP-2 and NCD was further corroborated by theoretical calculations. Oxygen treatment rendered NCD hydrophilic by the appearance of surface oxygen containing groups. This particular NCD surface exhibited even higher binding energies towards BMP-2 than the hydrophobic surface, and this surface was also favoured by cultured cells. Most importantly in this context, bound BMP-2 was found fully active. When cultured on BMP-2-treated NCD, osteosarcoma cells strongly up-regulated alkaline phosphatase, a specific marker for osteogenic differentiation. Hence, this simple method will allow generating highly versatile surfaces with complex biomimetic coatings, essentials for novel medical devices and implants as well as for innovative scaffolds in tissue engineering.
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| 33. |
- Strauss, Jens, et al.
(författare)
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Circum-Arctic Map of the Yedoma Permafrost Domain
- 2021
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Ingår i: Frontiers in Earth Science. - : Frontiers Media SA. - 2296-6463. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- Ice-rich permafrost in the circum-Arctic and sub-Arctic (hereafter pan-Arctic), such as late Pleistocene Yedoma, are especially prone to degradation due to climate change or human activity. When Yedoma deposits thaw, large amounts of frozen organic matter and biogeochemically relevant elements return into current biogeochemical cycles. This mobilization of elements has local and global implications: increased thaw in thermokarst or thermal erosion settings enhances greenhouse gas fluxes from permafrost regions. In addition, this ice-rich ground is of special concern for infrastructure stability as the terrain surface settles along with thawing. Finally, understanding the distribution of the Yedoma domain area provides a window into the Pleistocene past and allows reconstruction of Ice Age environmental conditions and past mammoth-steppe landscapes. Therefore, a detailed assessment of the current pan-Arctic Yedoma coverage is of importance to estimate its potential contribution to permafrost-climate feedbacks, assess infrastructure vulnerabilities, and understand past environmental and permafrost dynamics. Building on previous mapping efforts, the objective of this paper is to compile the first digital pan-Arctic Yedoma map and spatial database of Yedoma coverage. Therefore, we 1) synthesized, analyzed, and digitized geological and stratigraphical maps allowing identification of Yedoma occurrence at all available scales, and 2) compiled field data and expert knowledge for creating Yedoma map confidence classes. We used GIS-techniques to vectorize maps and harmonize site information based on expert knowledge. We included a range of attributes for Yedoma areas based on lithological and stratigraphic information from the source maps and assigned three different confidence levels of the presence of Yedoma (confirmed, likely, or uncertain). Using a spatial buffer of 20 km around mapped Yedoma occurrences, we derived an extent of the Yedoma domain. Our result is a vector-based map of the current pan-Arctic Yedoma domain that covers approximately 2,587,000 km2, whereas Yedoma deposits are found within 480,000 km2 of this region. We estimate that 35% of the total Yedoma area today is located in the tundra zone, and 65% in the taiga zone. With this Yedoma mapping, we outlined the substantial spatial extent of late Pleistocene Yedoma deposits and created a unique pan-Arctic dataset including confidence estimates.
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| 34. |
- Van De Munckhof, Anita, et al.
(författare)
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Outcomes of cerebral venous thrombosis due to vaccine-induced immune thrombotic thrombocytopenia after the acute phase
- 2022
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Ingår i: Stroke. - : American Heart Association. - 0039-2499 .- 1524-4628. ; 53:10, s. 3206-3210
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Tidskriftsartikel (refereegranskat)abstract
- Background: Cerebral venous thrombosis (CVT) due to vaccine-induced immune thrombotic thrombocytopenia (VITT) is a severe condition, with high in-hospital mortality rates. Here, we report clinical outcomes of patients with CVT-VITT after SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) vaccination who survived initial hospitalization.Methods: We used data from an international registry of patients who developed CVT within 28 days of SARS-CoV-2 vaccination, collected until February 10, 2022. VITT diagnosis was classified based on the Pavord criteria. Outcomes were mortality, functional independence (modified Rankin Scale score 0-2), VITT relapse, new thrombosis, and bleeding events (all after discharge from initial hospitalization).Results: Of 107 CVT-VITT cases, 43 (40%) died during initial hospitalization. Of the remaining 64 patients, follow-up data were available for 60 (94%) patients (37 definite VITT, 9 probable VITT, and 14 possible VITT). Median age was 40 years and 45/60 (75%) patients were women. Median follow-up time was 150 days (interquartile range, 94-194). Two patients died during follow-up (3% [95% CI, 1%-11%). Functional independence was achieved by 53/60 (88% [95% CI, 78%-94%]) patients. No new venous or arterial thrombotic events were reported. One patient developed a major bleeding during follow-up (fatal intracerebral bleed).Conclusions: In contrast to the high mortality of CVT-VITT in the acute phase, mortality among patients who survived the initial hospitalization was low, new thrombotic events did not occur, and bleeding events were rare. Approximately 9 out of 10 CVT-VITT patients who survived the acute phase were functionally independent at follow-up.
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| 35. |
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| 36. |
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| 37. |
- Wimmer, Matthias, et al.
(författare)
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3D mapping of sublevel caving (SLC) blast rings and ore flow disturbances in the LKAB Kiruna mine
- 2012
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Ingår i: MassMin 2012: Proceedings of the 6th International Conference and Exhibition on Mass Mining, Sudbury, Canada June 2012. - Sudbury, Canada : Canadian Institute of Mining, Metallurgy and Petroeum.
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Konferensbidrag (refereegranskat)abstract
- Sublevel caving (SLC) is a highly productive mining method with the major disadvantages of irrepressible ore loss and dilution. The confined blasting situation of SLC rings is commonly regarded to have a significant impact upon the material flow characteristics and hence on the overall performance. The initial conditions for the ore flow after blasting are unknown, as both the blasted geometry and the fragmentation itself are normally hidden. However, when opening a new drawpoint and in hang-up situations an inspection of the actual conditions is feasible. For this purpose, a remotely operated 3D photogrammetry system was custom built and used to reconstruct the ring front and/or cavity as a geo-referenced mesh model with colour information. Various blasting situations have been observed and this allowed a deeper study of the i) broken geometry and height, ii) over- and underbreak and their effects on subsequently blasted rings, iii) interaction effects between adjacent holes/rings, iv) drilling accuracy based on identified boreholes and v) mapping of geological structures and their influence on the blast result. The capabilities of the 3D image acquisition system to evaluate the blasting results are demonstrated with an example, in which a series of blasts were surveyed. Monitoring under hang-up situations, has then revealed the actual effects from confined blasting and gravity flow related issues. The 3D photogrammetry system is now increasingly being used to study hang-ups. By revealing and quantifying hitherto inaccessible information, the system has proven to be a valuable tool in increasing the understanding of both SLC breakage and flow.
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| 38. |
- Wimmer, Matthias, et al.
(författare)
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Referenced 3D images from inside cavities and behind rings in sublevel caving
- 2009
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Ingår i: Rock Fragmentation by Blasting. - Boca raton, Fla. : CRC Press. - 9780415482967 ; , s. 91-100
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Konferensbidrag (refereegranskat)abstract
- Disturbance free fragmentation and flow in sublevel caving (SLC) are desirable as they could lead to an increase in ore recovery and a decrease in waste rock loading and nitrates leakage. This requires a reasonable understanding of the actual rock breakage in semi-confined ring blasting situations, where both the blasted geometry and the breakage itself are hidden. Sometimes there is a chance to inspect the actual conditions, such as in the opening of a new drawpoint and in hang-ups in which cavities exist. For these situations a lightweight mobile camera crane has been constructed for use in the LKAB Kiruna mine. A 3D photogrammetry system has been constructed, which enables the reconstruction of the ring front/cavity as a geo-referenced mesh model with color information. It is remotely operated from a safe distance behind in the drift. The paper first reviews the current drill and blast practice. Then it presents the design, construction and application of the 3D image acquisition system. A case study shows the measurement application and also the evaluation possibilities. So far the system promises to be a valuable tool in increasing the understanding of SLC breakage and flow.
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| 39. |
- Wolffram, Daniel, et al.
(författare)
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Collaborative nowcasting of COVID-19 hospitalization incidences in Germany
- 2023
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Ingår i: PloS Computational Biology. - 1553-734X .- 1553-7358. ; 19:8
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Tidskriftsartikel (refereegranskat)abstract
- Real-time surveillance is a crucial element in the response to infectious disease outbreaks. However, the interpretation of incidence data is often hampered by delays occurring at various stages of data gathering and reporting. As a result, recent values are biased downward, which obscures current trends. Statistical nowcasting techniques can be employed to correct these biases, allowing for accurate characterization of recent developments and thus enhancing situational awareness. In this paper, we present a preregistered real-time assessment of eight nowcasting approaches, applied by independent research teams to German 7-day hospitalization incidences during the COVID-19 pandemic. This indicator played an important role in the management of the outbreak in Germany and was linked to levels of non-pharmaceutical interventions via certain thresholds. Due to its definition, in which hospitalization counts are aggregated by the date of case report rather than admission, German hospitalization incidences are particularly affected by delays and can take several weeks or months to fully stabilize. For this study, all methods were applied from 22 November 2021 to 29 April 2022, with probabilistic nowcasts produced each day for the current and 28 preceding days. Nowcasts at the national, state, and age-group levels were collected in the form of quantiles in a public repository and displayed in a dashboard. Moreover, a mean and a median ensemble nowcast were generated. We find that overall, the compared methods were able to remove a large part of the biases introduced by delays. Most participating teams underestimated the importance of very long delays, though, resulting in nowcasts with a slight downward bias. The accompanying prediction intervals were also too narrow for almost all methods. Averaged over all nowcast horizons, the best performance was achieved by a model using case incidences as a covariate and taking into account longer delays than the other approaches. For the most recent days, which are often considered the most relevant in practice, a mean ensemble of the submitted nowcasts performed best. We conclude by providing some lessons learned on the definition of nowcasting targets and practical challenges.
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| 40. |
- Zhou Hagström, Nanna, 1993-, et al.
(författare)
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Megahertz-rate Ultrafast X-ray Scattering and Holographic Imaging at the European XFEL
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence, and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, we present the results from the first megahertz repetition rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL. We illustrate the experimental capabilities that the SCS instrument offers, resulting from the operation at MHz repetition rates and the availability of the novel DSSC 2D imaging detector. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative examples, providing an ideal test-bed for operation at megahertz rates. Nevertheless, our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range.
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| 41. |
- Zhou Hagström, Nanna, 1993-, et al.
(författare)
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Megahertz-rate ultrafast X-ray scattering and holographic imaging at the European XFEL
- 2022
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Ingår i: Journal of Synchrotron Radiation. - : International Union of Crystallography (IUCr). - 0909-0495 .- 1600-5775. ; 29, s. 1454-1464
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Tidskriftsartikel (refereegranskat)abstract
- The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, results from the first megahertz-repetition-rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL are presented. The experimental capabilities that the SCS instrument offers, resulting from the operation at megahertz repetition rates and the availability of the novel DSSC 2D imaging detector, are illustrated. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative, providing an ideal test-bed for operation at megahertz rates. Our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range.
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