| 1. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)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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| 2. |
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| 3. |
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| 4. |
- Dimkovski, Zlate, et al.
(författare)
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Interference Measurements of Deposits on Cylinder Liner Surfaces
- 2011
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Ingår i: Wear. - Amsterdam : Elsevier. - 0043-1648 .- 1873-2577. ; 270:3-4, s. 247-251
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Tidskriftsartikel (refereegranskat)abstract
- The accumulation of deposits in the honing grooves of the cylinder liner surfaces of internal combustion engines is undesirable as they seal the grooves (reducing their oil retention capability) and increase engine's oil consumption. As part of a long-term programme of truck engine development, after different running times and under similar conditions of load, engine speed and lubrication, a number of grey iron cylinder liners were axially sectioned, measured, inspected and a presence of deposits was discovered. These deposits were characterised in order to gain knowledge about their origin and quantities. The X-ray energy dispersive analysis revealed elements stemming from the oil/fuel (C, O and S), from the detergent (Ca and Mg), from the anti-wear additive (Zn and P), and from some contaminants (K and Si). Higher concentration of S and Ca were mostly found in the honing grooves covered with deposits suggesting a domination of the detergent additive. Deposit thickness measurements obtained by a white light interferometer revealed patchy deposit topographies concentrated at the top region reducing towards the bottom of the liner which was also confirmed by scanning electron microscope measurements. Despite the limitations of the interferometer, it has been shown that the interference measurements are sufficiently reliable for a quick and objective quantification of the overall deposit accumulation.
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| 5. |
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| 6. |
- Rosén, Bengt Göran, 1962-, et al.
(författare)
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Analysis of 3-D surfaces in forming dies and sheet metal - Today and tomorrow
- 2004
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Ingår i: Proceedings of the International Conference on Recent Advances in Manufacture and Use of Tools and Dies and Stamping of Steel Sheets. ; , s. 29-53
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Konferensbidrag (refereegranskat)abstract
- The effects of surface roughness on production of steel sheet are critically reviewed. New developments in the measurement and characterisation of surface roughness seem likely to improve our understanding of its effect on sheet metal production. Much useful information can still be acquired by 2D techniques but increasingly the evidence is that sheet metal surface roughness is better measured and characterised by 3D methods. The facility for direct surface visualization in 3D is shown to be particularly helpful. When measuring 3D the measurement area size and sampling space are critical and for evaluation the filtering of surface data into roughness and waviness is more complicated than for 2D profiles.
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| 7. |
- Rosén, Bengt Göran, et al.
(författare)
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Topographical characterisation of artificial femoral heads : a Benchmarking study
- 2004
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Ingår i: Wear. - : Elsevier. - 0043-1648 .- 1873-2577. ; 257:12, s. 1275-1280
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Tidskriftsartikel (refereegranskat)abstract
- The main functional demands on artificial joints are that they last more than 20 years. This means optimising the friction coefficient to minimise forces transmitted to the surrounding bone and the wear of the contacting surfaces. Surface roughness has an important influence on friction and wear. Traditionally, the 2D Ra-parameter has been the preferred way to characterise the joint's topography. Today ongoing development of 3D techniques are available for the research, and the aim of the present paper is to highlight the importance and possibilities using high-resolution 3D atomic force microscope ( AFM) and the optical phase-shifting interferometer for texture characterisation of eight commercially available femoral heads. The results show a significant variation of topography and surface-lay for the different femoral heads in the study. The variation and difference between heads were further underlined by the use of different characterisation techniques and measuring strategy. Results highlight the importance of the selection of measurement strategy, parameters, instrumentation, and scale of measurement in order properly to characterise the femoral heads in this study.
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| 8. |
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| 9. |
- Rosén, Stefan, et al.
(författare)
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The Stedman diagram revisited
- 2014
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Ingår i: Surface Topography : Metrology and Properties. - Bristol : Institute of Physics (IOP). - 2051-672X. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- The Stedman diagram has been used for some years to display aspects of the performance of instruments measuring surface roughness. Such diagrams are herein employed to compare the features of a range of proprietary measuring instruments, including contact and non-contact devices. An extension of the basic diagram is proposed, which would allow it to include a further aspect: the speed of data collection. Figures of merit based on the revised diagram are computed, which enable instruments to be ranked on these particular aspects of their performance. Contact instruments emerge as comparable to non-contact, as their slower rate of data acquisition can be offset by the greater area they can access in amplitude–wavelength space. © 2014 IOP Publishing Ltd.
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| 10. |
- Rosén, Stefan, et al.
(författare)
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The Stedman diagram revisited
- 2013
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Ingår i: Metrology and Properties of Engineering Surfaces, 2013. ; , s. 201-206
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Konferensbidrag (refereegranskat)abstract
- The Stedman diagram has been used for some years to display aspects of the performance of surface roughness measuring instruments. Such diagrams are herein employed to compare the features of a range of proprietary measuring instruments, including contact and non-contact devices. An extension of the basic diagram is proposed which would allow it to include a further aspect, speed of data collection. Figures of merit based on the revised diagram are computed which enable instruments to be ranked on these particular aspects of their performance. Contact instruments emerge as comparable to non-contact, as their slower rate of data acquisition can be offset by the greater area they can access in amplitude-wavelength space.
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| 11. |
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| 12. |
- Anderson, Emma K., 1986-, et al.
(författare)
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Fragmentation of and electron detachment from hot copper and silver dimer anions : A comparison
- 2023
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Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - 2469-9926 .- 2469-9934. ; 107:6
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Tidskriftsartikel (refereegranskat)abstract
- We measured the spontaneous decays of internally hot copper and silver dimer anions, and , stored in one of the two ion-beam storage rings of the Double Electrostatic Ion Ring Experiment (DESIREE) at Stockholm University. A coincidence detection technique was utilized enabling essentially background-free measurements of -> Cu + Cu- and -> Ag + Ag- fragmentation rates. Furthermore, the total rates of neutral decay products (monomers and dimers) were measured and the relative contributions of fragmentation and electron emission ( -> Cu2 + e- and -> Ag2 + e-) were deduced as functions of storage time. Fragmentation is completely dominant at early times. However, after about 20 ms of storage, electron emission is observed and becomes the leading decay path after 100 ms for both dimer anions. The branching ratios between fragmentation and electron emission (vibrationally assisted autodetachment processes) are very nearly the same for and Ag-2 throughout the present storage cycle of 10 seconds. This is surprising considering the difference between the electron affinities of the neutral dimers, Cu2 and Ag2, and the difference between the and the dissociation energies.
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| 13. |
- Anderson, Emma K., et al.
(författare)
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Spontaneous electron emission from hot silver dimer anions: Breakdown of the Born-Oppenheimer approximation
- 2020
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 124
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Tidskriftsartikel (refereegranskat)abstract
- We report the first experimental evidence of spontaneous electron emission from a homonuclear dimer anion through direct measurements of Ag−2 → Ag2 + e− decays on milliseconds and seconds timescales. This observation is very surprising as there is no avoided crossing between adiabatic energy curves to mediate such a process. The process is weak, yet dominates the decay signal after 100 ms when ensembles of internally hot Ag−2 ions are stored in the cryogenic ion-beam storage ring, DESIREE, for 10 s. The electron emission process is associated with an instantaneous, very large reduction of the vibrational energy of the dimer system. This represents a dramatic deviation from a Born-Oppenheimer description of dimer dynamics.
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| 14. |
- Badr, Hussein O., et al.
(författare)
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Bottom-up, scalable synthesis of anatase nanofilament-based two-dimensional titanium carbo-oxide flakes
- 2022
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Ingår i: Materials Today. - : ELSEVIER SCI LTD. - 1369-7021 .- 1873-4103. ; 54
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Tidskriftsartikel (refereegranskat)abstract
- Two-dimensional (2D) materials offer advantages that their 3D counterparts do not. The conventional method for the bulk synthesis of 2D materials has predominantly been through etching layered solids. Herein, we convert - through a bottom-up approach - 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides into 2D flakes by immersing them in a tetramethylammonium hydroxide solution at temperatures in the 25-85 degrees C range. Based on X-ray diffraction, density functional theory, X-ray photoelectron, electron energy loss, Raman, X-ray absorption near edge structure spectroscopies, transmission and scanning electron microscope images and selected area diffraction, we conclude that the resulting flakes are carbon containing anatase-based layers that are, in turn, comprised of approximate to 6 x 10 angstrom(2) nanofilaments in cross-section some of which are few microns long. Electrodes made from some of these films performed well in lithium-ion and lithium-sulphur systems. These materials also reduce the viability of cancer cells thus showing potential in biomedical applications. Synthesizing 2D materials, at near ambient conditions, with non-layered, inexpensive, green precursors (e.g., TiC) is paradigm shifting and will undoubtedly open new and exciting avenues of research and applications.
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| 15. |
- Balogh, Johanna, et al.
(författare)
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Deletion of a lectin gene does not affect the phenotype of the nematode-trapping fungus Arthrobotrys oligospora
- 2003
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Ingår i: Fungal Genetics and Biology. - 1087-1845. ; 39:2, s. 128-135
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Tidskriftsartikel (refereegranskat)abstract
- A number of filamentous fungi are known to produce high levels of saline-soluble and low-molecular-mass lectins. The function of these proteins are not clear but it has been proposed that they are involved in storage of nutrients, development, recognition of other organisms, and defense reactions. A gene encoding such a lectin (AOL) was deleted in the nematode-trapping fungus Arthrobotrys oligospora by homologous recombination. The deletion mutants did not express any hemagglutinating activity or protein cross-reacting with AOL antibodies. There were no significant differences between the DeltaAOL and wild-type strains in spore (conidia) germination, saprophytic growth, and pathogenicity. Furthermore, there was no significant difference in the growth and reproduction of collembolan feeding on the various strains of A. oligospora. Thus either the previous proposed functions of AOL are not correct, or the fungus can compensate for the absence of the lectin by expressing other proteins with similar function(s) as AOL. (C) 2003 Published by Elsevier Science (USA).
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| 16. |
- Barklem, Paul, et al.
(författare)
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Mutual Neutralization in Li++H−/D− and Na++H−/D− Collisions : Implications of Experimental Results for Non-LTE Modeling of Stellar Spectra
- 2021
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 908:2
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Tidskriftsartikel (refereegranskat)abstract
- Advances in merged-beams instruments have allowed experimental studies of the mutual neutralization (MN) processes in collisions of both Li+ and Na+ ions with D− at energies below 1 eV. These experimental results place constraints on theoretical predictions of MN processes of Li+ and Na+ with H−, important for non-LTE modeling of Li and Na spectra in late-type stars. We compare experimental results with calculations for methods typically used to calculate MN processes, namely the full quantum (FQ) approach, and asymptotic model approaches based on the linear combination of atomic orbitals (LCAO) and semiempirical (SE) methods for deriving couplings. It is found that FQ calculations compare best overall with the experiments, followed by the LCAO, and the SE approaches. The experimental results together with the theoretical calculations, allow us to investigate the effects on modeled spectra and derived abundances and their uncertainties arising from uncertainties in the MN rates. Numerical experiments in a large grid of 1D model atmospheres, and a smaller set of 3D models, indicate that neglect of MN can lead to abundance errors of up to 0.1 dex (26%) for Li at low metallicity, and 0.2 dex (58%) for Na at high metallicity, while the uncertainties in the relevant MN rates as constrained by experiments correspond to uncertainties in abundances of much less than 0.01 dex (2%). This agreement for simple atoms gives confidence in the FQ, LCAO, and SE model approaches to be able to predict MN with the accuracy required for non-LTE modeling in stellar atmospheres.
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| 17. |
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| 18. |
- Bastard, Paul, et al.
(författare)
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Preexisting autoantibodies to type I IFNs underlie critical COVID-19 pneumonia in patients with APS-1.
- 2021
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Ingår i: The Journal of experimental medicine. - 1540-9538. ; 218:7
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Tidskriftsartikel (refereegranskat)abstract
- Patients with biallelic loss-of-function variants of AIRE suffer from autoimmune polyendocrine syndrome type-1 (APS-1) and produce a broad range of autoantibodies (auto-Abs), including circulating auto-Abs neutralizing most type I interferons (IFNs). These auto-Abs were recently reported to account for at least 10% of cases of life-threatening COVID-19 pneumonia in the general population. We report 22 APS-1 patients from 21 kindreds in seven countries, aged between 8 and 48 yr and infected with SARS-CoV-2 since February 2020. The 21 patients tested had auto-Abs neutralizing IFN-α subtypes and/or IFN-ω; one had anti-IFN-β and another anti-IFN-ε, but none had anti-IFN-κ. Strikingly, 19 patients (86%) were hospitalized for COVID-19 pneumonia, including 15 (68%) admitted to an intensive care unit, 11 (50%) who required mechanical ventilation, and four (18%) who died. Ambulatory disease in three patients (14%) was possibly accounted for by prior or early specific interventions. Preexisting auto-Abs neutralizing type I IFNs in APS-1 patients confer a very high risk of life-threatening COVID-19 pneumonia at any age.
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| 19. |
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| 20. |
- Bengtsson, Stefan, et al.
(författare)
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Accumulation of wet-deposited radiocaesium and radiostrontium by spring oilseed rape (Brássica napus L.) and spring wheat (Tríticum aestívum L.)
- 2013
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 182, s. 335-342
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Tidskriftsartikel (refereegranskat)abstract
- The accumulation of 134Cs and 85Sr within different parts of spring oilseed rape and spring wheat plants was investigated, with a particular focus on transfer to seeds after artificial wet deposition at different growth stages during a two-year field trial. In general, the accumulation of radionuclides in plant parts increased when deposition was closer to harvest. The seed of spring oilseed rape had lower concentrations of 85Sr than spring wheat grain. The plants accumulated more 134Cs than 85Sr. We conclude that radionuclides can be transferred into human food chain at all growing stages, especially at the later stages. The variation in transfer factors during the investigation, and in comparison to previous results, implies the estimation of the risks for possible transfer of radionuclides to seeds in the events of future fallout during a growing season is still subjected to considerable uncertainty.
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| 21. |
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| 22. |
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| 23. |
- Bengtsson, Stefan, et al.
(författare)
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Importance of soil type on internal distribution of radiocaesium and radiostrontium in barley, oat and wheat.
- 2012
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Ingår i: 13th International Congress of the International Radiation Protection Association (IRPA) in Glasgow, 13-18 May 2012.
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Konferensbidrag (refereegranskat)abstract
- The release of radionuclides to the atmosphere can result in deposition of the radionuclides directly to terrestrial ecosystems. Following deposition, uptake from soil will also contribute to the activity that is internalized in plants and further transported in the terrestrial ecosystems. These two processes are of concern in the nutrition chains, cereals-bread-human and in feeding stuffs-cow-milk-human. The aim of this study was to quantify the internal distribution of (1) direct wet deposited 134Cs and 85Sr in wheat and (2) root uptake of 137Cs, from Chernobyl accident, in barley and oats, as well as the dependence of distribution on soil type. Wheat crop was grown at the Ultuna meteorological and agricultural field station (Uppsala County) and land management was in accordance with regional agricultural practice. The trial had a randomized block design with 1 × 1 m2 parcels with three replicates. 134Cs and 85Sr were deposited on wheat at three different growth stages by a rainfall simulator. Barley crops was grown at Helganbo (Uppsala County) and Möjsjövik (Uppsala County) and oat crops was grown at Björke (Gävle County), Hille (Gävle County) and Möjsjövik (Uppsala County) all places were in Sweden. Both crops were grown in accordance with regional agricultural practices. Sampling was made in the last growing stage from an area of 1 m2 and the different plant compartments (stem, head, husk and grain) for all crops were dried. Samples were placed in plastic jars and the activity was measured by High Purity Germanium (HPGe) detectors, calibrated for this sample geometry. The preliminary results indicate that the lowest distribution of 137Cs was found to the head and grains of barley and oat grown on loamy clay soil type. There is an indication that the distribution of 134Cs to the head and grains in wheat is not related to the time from the deposition of 134Cs to harvest. It was found to that the distribution of 134Cs to head was higher in the husks then to the grains. For 85Sr it was seen that at a deposition at harvest the highest amount was distributed to the husks compared to the grains. However, at a deposition at the growing stage “flowering” a higher amount was distributed to the head. Factors that influenced distribution of radionuclides were the soil type, type of radionuclide and time interval between deposition and harvest.
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| 24. |
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| 25. |
- Bengtsson, Stefan, et al.
(författare)
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Interception and retention of wet-deposited radiocaesium and radiostrontium on a ley mixture of grass and clover
- 2014
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 497-498, s. 412-419
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Tidskriftsartikel (refereegranskat)abstract
- The aims of this study were to assess the potential radioactive contamination of fodder in the case of accidental radionuclide fallout, and to analyse the relationship between interception and retention of radionuclides as a function of biomass and Leaf Area Index (LAI). The interception and the retention of wet deposited Cs-134 and Sr-85 in ley (a mixture of grass and clover) were measured after artificial wet deposition in a field trial in Uppsala (eastern central Sweden). The field trial had a randomised block design with three replicates. Cs-134 and Sr-85 were deposited at six different growth stages during two growing seasons (2010 and 2011) using a rainfall simulator. The biomass was sampled in the center of each parcel 2 to 3 h after deposition and at later growth stages (1 to 5) during the growing season. The above ground biomass and LAI were measured as well. The interception of radionuclides by the ley was largest at the late growth stages; the spike and tassel/flowering (code 5:6) in the 1st year, and at flowering/initial flowering (code 6:5) in the 2nd year. There was a correlation between radionuclide interception and above ground plant biomass, as well as with LAI, for both radionuclides in both years. The highest activity concentrations of both radionuclides were measured after deposition at the late growth stages and were found to be higher in the 2nd year. The weathering half-lives were shorter at the earlier growth stages than at the later growth stages for both radionuclides. For the magnitude of deposition chosen in our experiment, it can be concluded that the above ground biomass is a good predictor and the LAI a more uncertain predictor of the interception of radiocaesium and radiostrontium by ley grass and clover. (C) 2014 Elsevier B.V. All rights reserved.
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| 26. |
- Bengtsson, Stefan, et al.
(författare)
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Interception of wet deposited and transfers of radiocaesiumand radiostrontium by Brássica napus L. and Tríticumaestívum L.
- 2011
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Ingår i: Radioprotection. - : EDP Sciences. - 0033-8451 .- 1769-700X. ; 46, s. S475-S478
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study is to assess the interception and transfer to edible part of wet deposited 134Cs and 85Sr to spring oilseed rape and spring wheat and the dependency of the intercepted fraction on the development stage e.g. the total plant biomass. The radionuclides, 134Cs and 85Sr, were deposited at six different development stages using a rainfall simulator. The results showed that there was a positive correlation between the interception fraction for 134Cs and 85Sr and the biomass both for spring oilseed rape and spring wheat. The interception fraction and transfer factors were highest at growing stage of senescence (ripening) for both crops
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| 27. |
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| 28. |
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| 29. |
- Bengtsson, Stefan, et al.
(författare)
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Uptake and Retention of Simulated Fallout of Radiocaesium and Radiostrontium by Different Agriculture Crops
- 2015
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Ingår i: Radionuclides in the Environment. - Cham : Springer International Publishing. - 9783319221700 ; , s. 115-132
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Abstract: The contamination level in potato, oilseed rape and wheat in terms of tubers, seeds and foliage has been investigated after the foliar application of wet-deposited 134Cs and 85Sr at different growth stages in a microscale field experiment conducted over consecutive years. The results indicate that the application of radionuclides in the beginning of the growth season resulted in low 134Cs and 85Sr activity in both seeds of wheat, oilseed rape and potato tubers across sampling occasions. In the middle of the growth season during radionuclide fallout, 134Cs activity in potato tubers across sampling occasions was highest. The spraying of radionuclides at later stages resulted in even lower 134Cs activity in potato tubers but increased activity in seeds of wheat and oilseed rape.
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| 30. |
- Beniczky, Sandor, et al.
(författare)
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Standardized Computer-based Organized Reporting of EEG: SCORE
- 2013
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Ingår i: Epilepsia. - : Wiley. - 0013-9580 .- 1528-1167. ; 54:6, s. 1112-1124
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Tidskriftsartikel (refereegranskat)abstract
- The electroencephalography (EEG) signal has a high complexity, and the process of extracting clinically relevant features is achieved by visual analysis of the recordings. The interobserver agreement in EEG interpretation is only moderate. This is partly due to the method of reporting the findings in free-text format. The purpose of our endeavor was to create a computer-based system for EEG assessment and reporting, where the physicians would construct the reports by choosing from predefined elements for each relevant EEG feature, as well as the clinical phenomena (for video-EEG recordings). A working group of EEG experts took part in consensus workshops in Dianalund, Denmark, in 2010 and 2011. The faculty was approved by the Commission on European Affairs of the International League Against Epilepsy (ILAE). The working group produced a consensus proposal that went through a pan-European review process, organized by the European Chapter of the International Federation of Clinical Neurophysiology. The Standardised Computer-based Organised Reporting of EEG (SCORE) software was constructed based on the terms and features of the consensus statement and it was tested in the clinical practice. The main elements of SCORE are the following: personal data of the patient, referral data, recording conditions, modulators, background activity, drowsiness and sleep, interictal findings, episodes (clinical or subclinical events), physiologic patterns, patterns of uncertain significance, artifacts, polygraphic channels, and diagnostic significance. The following specific aspects of the neonatal EEGs are scored: alertness, temporal organization, and spatial organization. For each EEG finding, relevant features are scored using predefined terms. Definitions are provided for all EEG terms and features. SCORE can potentially improve the quality of EEG assessment and reporting; it will help incorporate the results of computer-assisted analysis into the report, it will make possible the build-up of a multinational database, and it will help in training young neurophysiologists.
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| 31. |
- Beniczky, Sándor, et al.
(författare)
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Standardized computer-based organized reporting of EEG : SCORE - Second version
- 2017
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Ingår i: Clinical Neurophysiology. - : Elsevier BV. - 1388-2457. ; 128:11, s. 2334-2346
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Tidskriftsartikel (refereegranskat)abstract
- Standardized terminology for computer-based assessment and reporting of EEG has been previously developed in Europe. The International Federation of Clinical Neurophysiology established a taskforce in 2013 to develop this further, and to reach international consensus. This work resulted in the second, revised version of SCORE (Standardized Computer-based Organized Reporting of EEG), which is presented in this paper. The revised terminology was implemented in a software package (SCORE EEG), which was tested in clinical practice on 12,160 EEG recordings. Standardized terms implemented in SCORE are used to report the features of clinical relevance, extracted while assessing the EEGs. Selection of the terms is context sensitive: initial choices determine the subsequently presented sets of additional choices. This process automatically generates a report and feeds these features into a database. In the end, the diagnostic significance is scored, using a standardized list of terms. SCORE has specific modules for scoring seizures (including seizure semiology and ictal EEG patterns), neonatal recordings (including features specific for this age group), and for Critical Care EEG Terminology. SCORE is a useful clinical tool, with potential impact on clinical care, quality assurance, data-sharing, research and education.
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| 32. |
- Bjureland, William
(författare)
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On reliability-based design of rock tunnel support
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Tunneling involves large uncertainties. Since 2009, design of rock tunnels in European countries should be performed in accordance with the Eurocodes. The main principle in the Eurocodes is that it must be shown in all design situations that no relevant limit state is exceeded. This can be achieved with a number of different methods, where the most common one is design by calculation. To account for uncertainties in design, the Eurocode states that design by calculation should primarily be performed using limit state design methods, i.e. the partial factor method or reliability-based methods. The basic principle of the former is that it shall be assured that a structure’s resisting capacity is larger than the load acting on the structure, with high enough probability. Even if this might seem straightforward, the practical application of limit state design to rock tunnel support has only been studied to a limited extent.The aim of this licentiate thesis is to provide a review of the practical applicability of using reliability-based methods and the partial factor method in design of rock tunnel support. The review and the following discussion are based on findings from the cases studied in the appended papers. The discussion focuses on the challenges of applying fixed partial factors, as suggested by Eurocode, in design of rock tunnel support and some of the practical difficulties the engineer is faced with when applying reliability-based methods to design rock tunnel support.The main conclusions are that the partial factor method (as defined in Eurocode) is not suitable to use in design of rock tunnel support, but that reliability-based methods have the potential to account for uncertainties present in design, especially when used within the framework of the observational method. However, gathering of data for statistical quantification of input variables along with clarification of the necessary reliability levels and definition of “failure” are needed.
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| 33. |
- Bjureland, William
(författare)
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Reliability-based design of rock tunnel support
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Since 2009, design of rock tunnels can be performed in accordance with the Eurocodes, which allows that different design methodologies are applied, such as design by calculation or design using the observational method. To account for uncertainties in design, the Eurocode states that design by calculation should primarily be performed using the partial factor method or reliability-based methods. The basic principle of both of these methods is that it shall be assured that a structure’s resisting capacity is larger than the load acting on the structure, with sufficiently high probability. Even if this might seem straightforward, the practical application of limit state design to rock tunnel support has only been studied to a limited extent.The overall aim of this project has been to develop reliability-based methods for environmental and economic optimization of rock tunnel support, with a special focus on shotcrete support. To achieve this, this thesis aims to: (1) assess the applicability of the partial factor method and reliability-based methods for design of shotcrete support, exclusively or in combination with the observational method, (2) quantify the magnitude and uncertainty of the shotcrete’s input parameters, and (3) assess the influence from spatial variability on shotcrete’s load-bearing capacity and judge the correctness of the assumption that the load-bearing capacity of the support is governed by the mean values of its input parameters.The thesis shows that the partial factor method is not suitable, and in some cases not applicable, to use in design of rock tunnel support. Instead, the thesis presents a reliability-based design methodology for shotcrete in rock tunnels with respect to loose blocks between rockbolts and a design methodology for shotcrete lining based on a combination of the observational method and reliability-based methods. The presented design methodologies enable optimization of the shotcrete support and shotcrete lining by stringently accounting for uncertainties related to input data throughout the design process. The thesis also discusses the limited knowledge that we as an industry sometimes have in our calculation models and the clarifications that should be made in future revisions of the Eurocode related to target reliability and the definition of failure.
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| 34. |
- Bogot, Alon, et al.
(författare)
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The mutual neutralization of hydronium and hydroxide
- 2024
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Ingår i: Science. - 0036-8075 .- 1095-9203. ; 383:6680, s. 285-289
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Tidskriftsartikel (refereegranskat)abstract
- Mutual neutralization of hydronium (H3O+) and hydroxide (OH−) ions is a very fundamental chemical reaction. Yet, there is only limited experimental evidence about the underlying reaction mechanisms. Here, we report three-dimensional imaging of coincident neutral products of mutual-neutralization reactions at low collision energies of cold and isolated ions in the cryogenic double electrostatic ion-beam storage ring (DESIREE). We identified predominant H2O + OH + H and 2OH + H2 product channels and attributed them to an electron-transfer mechanism, whereas a minor contribution of H2O + H2O with high internal excitation was attributed to proton transfer. The reported mechanism-resolved internal product excitation, as well as collision-energy and initial ion-temperature dependence, provide a benchmark for modeling charge-transfer mechanisms.
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| 35. |
- Boman, Björn, 1984-
(författare)
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Skolprestationer : Faktorer som är relaterade till studieresultat i grundskolans senare år
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This compilation dissertation explores school results (or alterably, educational or academic achievement) at the Swedish lower-secondary level (Grades 7–9), particularly Grade 9 and to lesser extent Grade 8, using both aggregated data at the school and municipality level from Swedish National Agency for Education (Skolverket) and similar databases (Sweden Statistics, Kolada), and individual data from Education through follow-up (UGU, utvärdering genom uppföljning), and the Programme for international student assessment, PISA (2018). Data were obtained from the years 2013, 2018, and 2019. The outcome variables consisted either of the sum score grades at least E (where E is the lowest pass grade and A is the highest) in all subjects or grade point average (either in all 17 subjects or a sum of English, Mathematics and Swedish), national test results (English, Mathematics, Swedish, Swedish as a second language), or PISA scores in mathematics and reading. The theoretical framework hinged on a socio-ecological model which covers the micro- (individuals, families), meso- (schools), macro levels (social factors such as political systems and social changes) of school results in different contexts. This rather comprehensive approach to school results was in turn related to six main variables that aimed to explain the variation in academic achievement, mostly by using linear regression models: socioeconomic status (SES, such as average parental education or resources within municipalities, schools or families), migration background (i.e., differences between native-born students and first- and second-generation migrant students), cognitive ability (i.e., the scores obtained from cognitive ability tests), non-cognitive abilities (e.g., the degree to which students regard themselves as being able to handle their school situation), teacher competence or teaching quality (i.e., mostly formal teacher competence such as the degree to which municipalities have teachers with a formal degree in teaching), as well as the geographical position of municipalities and students. The findings, which are related to four different studies, indicate that when all six variables were included in the same regression models (only in the UGU study), cognitive ability was the strongest factor, followed by non-cognitive abilities, SES, teaching quality, migration background, and geographical position. In some regression models, migration background was not even statistically significant, which was also the case with geographical position. When exploring the aggregated Skolverket data, the SES variables were the strongest, followed by migration background, and teacher competence, while geographical position was only statistically significant when the municipalities whose school results were the highest were compared with their lowest counterparts. The study which was built on PISA data and used a multi-level model approach, found a much stronger effect for migration background at the within-school level, which may be because students with a migration background have difficulties in understanding the long and reading-intense PISA tasks. It might also be because PISA does not include cognitive ability indicators. Moreover, for reading achievement, some non-cognitive abilities were also important such as self-assessed reading capabilities. At the between-school level, differences were associated with reading motivation. These results reflect upon recent phenomena in the Swedish context such as individualisation (the emphasis on individual level factors), socioeconomic disparities, and migration (social change).
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| 36. |
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| 37. |
- Bäckström, Erik, 1983-, et al.
(författare)
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Storing keV negative ions for an hour : The lifetime of the metastable 2P1/2 level in 32S−
- 2015
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 114:14
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Tidskriftsartikel (refereegranskat)abstract
- We use a novel electrostatic ion storage ring to measure the radiative lifetime of the upper level in the 3p 5 P 2 o 1/2 →3p 5 P 2 o 3/2 spontaneous radiative decay in S − 32 to be 503±54 sec . This is by orders of magnitude the longest lifetime ever measured in a negatively charged ion. Cryogenic cooling of the storage ring gives a residual-gas pressure of a few times 10 −14 mbar at 13 K and storage of 10 keV sulfur anions for more than an hour. Our experimental results differ by 1.3σ from the only available theoretical prediction.
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| 38. |
- Chartkunchand, Kiattichart C., et al.
(författare)
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Dianion diagnostics in DESIREE : High-sensitivity detection of C-n(2-) from a sputter ion source
- 2018
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 89:3
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Tidskriftsartikel (refereegranskat)abstract
- A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, C-n(2-), with n = 7-24. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot C-n(2-) dianions injected into the ring yielded C-n(2-) anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a 90 degrees analyzing magnet on the ion injection line reflect the production of internally hot C-7(2-) - C-24(2-) dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of C-6(2-) was found while there was a clear C-7(2-) signal with the expected isotopic distribution. This is consistent with earlier experimental studies and with theoretical predictions. An upper limit is deduced for a C-6(2-) signal that is two orders-of-magnitude smaller than that for C-7(2-). In addition, CnO2- and CnCu2- dianions were detected.
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| 39. |
- Chartkunchand, Kiattichart C., et al.
(författare)
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Radiative lifetimes of the bound excited states of Pt-
- 2016
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Ingår i: Physical Review A - Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 94:3
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Tidskriftsartikel (refereegranskat)abstract
- © 2016 American Physical Society.The intrinsic radiative lifetimes of the 5d106sS1/22 and 5d96s2 D3/22 bound excited states in the platinum anion Pt- have been studied at cryogenic temperatures at the Double ElectroStatic Ion Ring Experiment (DESIREE) facility at Stockholm University. The intrinsic lifetime of the higher-lying 5d106s S1/22 state was measured to be 2.54±0.10s, while only a lifetime in the range of 50-200 ms could be estimated for the 5d96s2 D3/22 fine-structure level. The storage lifetime of the Pt- ion beam was measured to be a little over 15 min at a ring temperature of 13K. The present study reports the lifetime of an atomic negative ion in an excited bound state with an electron configuration different from that of the ground state.
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| 40. |
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| 41. |
- Claeson, Magdalena, 1976, et al.
(författare)
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Modelling the Future: System Dynamics in the Cutaneous Malignant Melanoma Care Pathway
- 2016
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Ingår i: Acta dermato-venereologica. - : Medical Journals Sweden AB. - 1651-2057 .- 0001-5555. ; 96:2, s. 181-185
-
Tidskriftsartikel (refereegranskat)abstract
- Incidence rates for cutaneous malignant melanoma are increasing worldwide. Estimates of the future number of melanoma cases are important for strategic planning of the care pathway. The aim of this study was to use system dynamics modelling to evaluate the long-term effects of changes in incidence, population growth and preventive interventions. Historical data on invasive melanoma cases in Western Sweden from 1990 to 2006 were obtained. Using computer simulation software, a model estimating the accumulated number of melanoma cases for 2014 to 2023 was developed. Five future scenarios were designed: stable incidence, business-as-usual, 25% reduced patient's delay, 50% reduced doctor's delay, and a combination of the last 2, called improved overall secondary prevention. After 10 years, improved overall secondary prevention would have resulted in a 42% decrease in melanomas >4 mm and a 10% increase in melanomas ≤1 mm, compared with business-as-usual. System dynamics is a valuable tool, which can help policymakers choose the preventive interventions with the greatest impact.
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| 42. |
- Claeson, Magdalena, 1976, et al.
(författare)
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Multiple primary melanomas in Western Sweden; 1990-2013
- 2016
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Ingår i: 3rd International Conference on UV and Skin Cancer Prevention, Melbourne.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- IntroductionIn Sweden, the incidence of cutaneous malignant melanoma rises yearly with 5.5% for men and 5.2% for women and has now reached world standard rates of 17.6 for men and 18.8 for women per 100,000 population. Over the past decades, the incidence of melanoma has been higher in Western Sweden than the national average. Previous international studies have shown that melanoma patients have an elevated risk of developing a new separate primary melanoma. This study aimed at describing multiple primary melanomas (MPMs) in Western Sweden with focus on the number of tumours detected, tumour characteristics and the time to diagnosis of a subsequent melanoma.MethodsData was extracted retrospectively from the Swedish Melanoma Registry and provided information on all invasive and in situ melanoma cases in Western Sweden (1.6 million inhabitants) from 1990 to 2013. Results Within the studied period, 12,152 patients developed 13,291 melanomas. 11,254 of the patients developed only a single primary melanoma. In total, 898 patients (7.4% of all melanoma patients) developed 2,037 MPMs. Preliminary results show that the median Breslow thickness for all invasive melanomas was below 1 mm. The median Breslow thickness for the MPMs was slightly thinner for the second and third invasive melanoma as compared to the first invasive melanoma. Further, there was a higher percentage of in situ tumours among the subsequent melanomas. The median time to diagnosis of a subsequent melanoma was approximately 3 years. DiscussionSubsequent primary melanomas in Western Sweden are most commonly diagnosed with a somewhat thinner Breslow thickness than the first primary melanoma. The comparatively high percentage of melanoma survivors developing MPMs and the short median time to diagnosis of a subsequent melanoma stresses the importance of follow-up for melanoma patients, particularly during the first years.
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| 43. |
- Claeson, Magdalena, 1976, et al.
(författare)
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MultiplePrimary Melanomas: A Common Occurrencein Western Sweden.
- 2017
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Ingår i: Acta dermato-venereologica. - : Medical Journals Sweden AB. - 1651-2057 .- 0001-5555. ; 97:6, s. 715-719
-
Tidskriftsartikel (refereegranskat)abstract
- Patients diagnosed with a single primary cutaneous melanoma are at increased risk of developing multiple primary melanomas. The aim of this study is to describe the epidemiology of multiple primary melanomas (invasive and in situ) in Western Sweden. Data from the Swedish Melanoma Registry from 1990 to 2013 revealed that 898 patients (7.4%) developed 2,037 multiple primary lesions and 11,254 patients developed single lesions. The proportion of subsequent lesions that were melanoma in situ was 47%, compared with 26% of first melanomas (p<0.0001). The median time to diagnosis of a subsequent melanoma was 38 months (95% confidence interval (CI), 53-62 months). In total, 49% of subsequent melanomas were detected within 3 years. Patients and physicians should be aware of the high proportion of multiple primary melanomas in Western Sweden, especially during the first years of follow-up.
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| 44. |
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| 45. |
- Eklund, Gustav, et al.
(författare)
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Cryogenic merged-ion-beam experiments in DESIREE : Final-state-resolved mutual neutralization of Li+ and D-
- 2020
-
Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - : American Physical Society (APS). - 2469-9926 .- 2469-9934. ; 102:1
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Tidskriftsartikel (refereegranskat)abstract
- We have developed an experimental technique to study charge-and energy-flow processes in sub-eV collisions between oppositely charged, internally cold, ions of atoms, molecules, and clusters. Two ion beams are stored in separate rings of the cryogenic ion-beam storage facility DESIREE, and merged in a common straight section where a set of biased drift tubes is used to control the center-of-mass collision energy locally in fine steps. Here, we present measurements on mutual neutralization between Li+ and D- where a time-sensitive imaging-detector system is used to measure the three-dimensional distance between the neutral Li and D atoms as they reach the detector. This scheme allows for direct measurements of kinetic-energy releases, and here it reveals separate populations of the 3s state and the (3p + 3d) states in neutral Li while the D atom is left in its ground state 1s. The branching fraction of the 3s final state is measured to be 57.8 +/- 0.7% at a center-of-mass collision energy of 78 +/- 13 meV. The technique paves the way for studies of charge-, energy-, and mass-transfer reactions in single collisions involving molecular and cluster ions in well-defined quantum states.
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| 46. |
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| 47. |
- Eklund, Gustav, et al.
(författare)
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Final-state-resolved mutual neutralization of Na+ and D-
- 2021
-
Ingår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information. - : American Physical Society. - 2469-9926 .- 2469-9934. ; 103:3
-
Tidskriftsartikel (refereegranskat)abstract
- The present paper reports on a merged-beam experiment on mutual neutralization between Na+ and D-. For this experiment, we have used the DESIREE ion-beams storage-ring facility. The reaction products are detected using a position- and time-sensitive detector, which ideally allows for determination of the population of each individual quantum state in the final atomic systems. Here, the 4s, 3d, and 4p final states in Na are observed and in all cases the D atom is in its ground state 1s S-2. The respective branching fractions of the states populated in Na are determined by fitting results from a Monte Carlo simulation of the experiment to the measured data. The center-of-mass collision energy is controlled using a set of biased drift tubes, and the branching fractions are measured for energies between 80 meV and 393 meV. The resulting branching fractions are found to agree qualitatively with the only available theoretical calculations for this particular system, which are based on a multichannel Landau-Zener approach using dynamic couplings determined with a linear combination of atomic orbitals model.
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| 48. |
- Emri, T, et al.
(författare)
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Effect of vitamin E on autolysis and sporulation of Aspergillus nidulans
- 2004
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Ingår i: Applied Biochemistry and Biotechnology. - 1559-0291. ; 118:1-3, s. 337-348
-
Tidskriftsartikel (refereegranskat)abstract
- The morphologic and physiologic effects of vitamin E, a powerful antioxidant, on the autolysis and sporulation of Aspergillus nidulans FGSC26 were studied. In carbon-depleted submerged cultures, reactive oxygen species (ROS) accumulated in the cells and, concomitantly, progressing autolysis was observed, which was characterized by decreasing dry cell masses and pellet diameters as well as by increasing extracellular chitinase activities. Vitamin E supplemented at a concentration of 1g/L hindered effectively the intracellular accumulation of ROS, the autolytic loss of biomass, the disintegration of pellets, and the release of chitinase activities. In surface cultures, vitamin E inhibited autolysis of both A. nidulans FGSC26 and a loss-of-function FlbA autolytic phenotype mutant. In addition, supplementation of the culture medium with this antioxidant also had a negative effect on the sporulation of strain FGSC26 and the FadA(G203R) hypersporulating phenotype mutant. These results suggest that accumulation of ROS was involved in the initiation of both sporulation and autolysis in this filamentous fungus, but that FadA/FlbA signaling was not involved in this vitamin E-dependent regulation. Vitamin E can be recommended as a supplement in fermentations in which the disintegration of pellets and gross autolysis should be avoided.
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| 49. |
- Gatchell, Michael, et al.
(författare)
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Commissioning of the DESIREE storage rings - a new facility for cold ion-ion collisions
- 2014
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Ingår i: XXVIII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2013). - : Institute of Physics (IOP). ; 488:1
-
Konferensbidrag (refereegranskat)abstract
- We report on the ongoing commissioning of the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. Beams of atomic carbon anions (C-) and smaller carbon anion molecules (C-2(-), C-3(-), C-4(-) etc.) have been produced in a sputter ion source, accelerated to 10 keV or 20 keV, and stored successfully in the two electrostatic rings. The rings are enclosed in a common vacuum chamber cooled to below 13 Kelvin. The DESIREE facility allows for studies of internally relaxed single isolated atomic, molecular and cluster ions and for collision experiments between cat-and anions down to very low center-of-mass collision energies (meV scale). The total thermal load of the vacuum chamber at this temperature is measured to be 32 W. The decay rates of stored ion beams have two components: a non-exponential component caused by the space charge of the beam itself which dominates at early times and an exponential term from the neutralization of the beam in collisions with residual gas at later times. The residual gas limited storage lifetime of carbon anions in the symmetric ring is over seven minutes while the 1/e lifetime in the asymmetric ring is measured to be about 30 seconds. Although we aim to improve the storage in the second ring, the number of stored ions are now sufficient for many merged beams experiments with positive and negative ions requiring milliseconds to seconds ion storage.
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| 50. |
- Gatchell, Michael, et al.
(författare)
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First results from the Double ElectroStatic Ion-Ring ExpEriment, DESIREE
- 2014
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Ingår i: XXVIII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2013). - : Institute of Physics (IOP). ; 488
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Konferensbidrag (refereegranskat)abstract
- We have stored the first beams in one of the rings of the double electrostatic ion-storage ring, DESIREE at cryogenic and at room temperature conditions. At cryogenic operations the following parameters are found. Temperature; T= 13K, pressure; p <10(-13) mbar, initial number of stored ions; N > 10(7) and storage lifetime of a C-2(-) beam; tau = 450 S.
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