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Sökning: WFRF:(Johnsson T) > (2015-2019)

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1.
  • Iablonskyi, D., et al. (författare)
  • Interatomic Coulombic Decay Processes after Multiple Valence Excitations in Ne Clusters
  • 2015
  • Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112067-112067
  • Konferensbidrag (refereegranskat)abstract
    • We present a comprehensive analysis of autoionization processes in Ne clusters (similar to 5000 atoms) after multiple valence excitations by free electron laser radiation. The evolution from 2-body interatomic Coulombic decay (ICD) to 3-body ICD is demonstrated when changing from surface to bulk Frenkel exciton excitation. Super Coster-Kronig type 2-body ICD is observed at Wannier exciton which quenches the main ICD channel.
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2.
  • Iablonskyi, D., et al. (författare)
  • Slow Interatomic Coulombic Decay of Multiply Excited Neon Clusters
  • 2016
  • Ingår i: Physical Review Letters. - 0031-9007. ; 117:27
  • Tidskriftsartikel (refereegranskat)abstract
    • Ne clusters (∼5000 atoms) were resonantly excited (2p→3s) by intense free electron laser (FEL) radiation at FERMI. Such multiply excited clusters can decay nonradiatively via energy exchange between at least two neighboring excited atoms. Benefiting from the precise tunability and narrow bandwidth of seeded FEL radiation, specific sites of the Ne clusters were probed. We found that the relaxation of cluster surface atoms proceeds via a sequence of interatomic or intermolecular Coulombic decay (ICD) processes while ICD of bulk atoms is additionally affected by the surrounding excited medium via inelastic electron scattering. For both cases, cluster excitations relax to atomic states prior to ICD, showing that this kind of ICD is rather slow (picosecond range). Controlling the average number of excitations per cluster via the FEL intensity allows a coarse tuning of the ICD rate.
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3.
  • Sanchez-Gonzalez, A., et al. (författare)
  • Auger electron and photoabsorption spectra of glycine in the vicinity of the oxygen K-edge measured with an X-FEL
  • 2015
  • Ingår i: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 48:23
  • Tidskriftsartikel (refereegranskat)abstract
    • We report the first measurement of the near oxygen K-edge auger spectrum of the glycine molecule. Our work employed an x-ray free electron laser as the photon source operated with input photon energies tunable between 527 and 547 eV. Complete electron spectra were recorded at each photon energy in the tuning range, revealing resonant and non-resonant auger structures. Finally ab initio theoretical predictions are compared with the measured above the edge auger spectrum and an assignment of auger decay channels is performed.
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4.
  • Düsterer, S, et al. (författare)
  • Two-color XUV+NIR femtosecond photoionization of neon in the near-threshold region
  • 2019
  • Ingår i: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 21
  • Tidskriftsartikel (refereegranskat)abstract
    • Results of angle-resolved electron spectroscopy of near-threshold photoionization of Ne atoms by combined femtosecond extreme ultraviolet and near infrared fields are presented. The dressed-electron spectra show an energetic distribution into so-called sidebands, being separated by the photon energy of the dressing laser. Surprisingly, for the low kinetic energy (few eV) sidebands, the photoelectron energy varies as a function of the emission angle. Such behavior has not yet been observed in sideband creation and has not been predicted in commonly used theoretical descriptions such as strong field approximation and soft photon approach. Describing the photoionization with a time-dependent Schrödinger equation allows a qualitative description of the observed effect, as well as the prediction of fine structure in the sideband distribution.
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5.
  • Takanashi, T, et al. (författare)
  • Time-Resolved Measurement of Interatomic Coulombic Decay Induced by Two-Photon Double Excitation of Ne2
  • 2017
  • Ingår i: Physical Review Letters. - 0031-9007. ; 118:3
  • Tidskriftsartikel (refereegranskat)abstract
    • The hitherto unexplored two-photon doubly excited states [Ne∗(2p-13s)]2 were experimentally identified using the seeded, fully coherent, intense extreme ultraviolet free-electron laser FERMI. These states undergo ultrafast interatomic Coulombic decay (ICD), which predominantly produces singly ionized dimers. In order to obtain the rate of ICD, the resulting yield of Ne2+ ions was recorded as a function of delay between the extreme ultraviolet pump and UV probe laser pulses. The extracted lifetimes of the long-lived doubly excited states, 390(-130/+450) fs, and of the short-lived ones, less than 150 fs, are in good agreement with ab initio quantum mechanical calculations.
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6.
  • Düsterer, S., et al. (författare)
  • Angle resolved photoelectron spectroscopy of two-color XUV-NIR ionization with polarization control
  • 2016
  • Ingår i: Journal of Physics B: Atomic, Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 49:16
  • Tidskriftsartikel (refereegranskat)abstract
    • Electron emission caused by extreme ultraviolet (XUV) radiation in the presence of a strong near infrared (NIR) field leads to multiphoton interactions that depend on several parameters. Here, a comprehensive study of the influence of the angle between the polarization directions of the NIR and XUV fields on the two-color angle-resolved photoelectron spectra of He and Ne is presented. The resulting photoelectron angular distribution strongly depends on the orientation of the NIR polarization plane with respect to that of the XUV field. The prevailing influence of the intense NIR field over the angular emission characteristics for He(1s) and Ne(2p) ionization lines is shown. The underlying processes are modeled in the frame of the strong field approximation (SFA) which shows very consistent agreement with the experiment reaffirming the power of the SFA for multicolor-multiphoton ionization in this regime.
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7.
  • Fukuzawa, H., et al. (författare)
  • Electron spectroscopy of rare-gas clusters irradiated by x-ray free-electron laser pulses from SACLA
  • 2016
  • Ingår i: Journal of Physics B-Atomic Molecular and Optical Physics. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 49:3
  • Tidskriftsartikel (refereegranskat)abstract
    • We have measured electron energy spectra and asymmetry parameters of Ar clusters and Xe clusters illuminated by intense x-rays at 5 and 5.5 keV. A velocity map imaging spectrometer was developed for this purpose and employed at an x-ray free-electron laser facility, SACLA in Japan. The cluster size dependence and the peak fluence dependence of the electron spectra and asymmetry parameters are discussed.
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8.
  • Tachibana, T., et al. (författare)
  • Nanoplasma Formation by High Intensity Hard X-rays
  • 2015
  • Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 5
  • Tidskriftsartikel (refereegranskat)abstract
    • Using electron spectroscopy, we have investigated nanoplasma formation from noble gas clusters exposed to high-intensity hard-x-ray pulses at similar to 5 keV. Our experiment was carried out at the SPring-8 Angstrom Compact free electron LAser (SACLA) facility in Japan. Dedicated theoretical simulations were performed with the molecular dynamics tool XMDYN. We found that in this unprecedented wavelength regime nanoplasma formation is a highly indirect process. In the argon clusters investigated, nanoplasma is mainly formed through secondary electron cascading initiated by slow Auger electrons. Energy is distributed within the sample entirely through Auger processes and secondary electron cascading following photoabsorption, as in the hard x-ray regime there is no direct energy transfer from the field to the plasma. This plasma formation mechanism is specific to the hard-x-ray regime and may, thus, also be important for XFEL-based molecular imaging studies. In xenon clusters, photo-and Auger electrons contribute more significantly to the nanoplasma formation. Good agreement between experiment and simulations validates our modelling approach. This has wide-ranging implications for our ability to quantitatively predict the behavior of complex molecular systems irradiated by high-intensity hard x-rays.
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9.
  • Ahmed, J., et al. (författare)
  • Automated diagnostic of virtualized service performance degradation
  • 2018
  • Ingår i: Proceedings 2018 IEEE/IFIP Network Operations and Management Symposium, NOMS 2018. - New York : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 1-9
  • Konferensbidrag (refereegranskat)abstract
    • Service assurance for cloud applications is a challenging task and is an active area of research for academia and industry. One promising approach is to utilize machine learning for service quality prediction and fault detection so that suitable mitigation actions can be executed. In our previous work, we have shown how to predict service-level metrics in real-time just from operational data gathered at the server side. This gives the service provider early indications on whether the platform can support the current load demand. This paper provides the logical next step where we extend our work by proposing an automated detection and diagnostic capability for the performance faults manifesting themselves in cloud and datacenter environments. This is a crucial task to maintain the smooth operation of running services and minimizing downtime. We demonstrate the effectiveness of our approach which exploits the interpretative capabilities of Self- Organizing Maps (SOMs) to automatically detect and localize different performance faults for cloud services.
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10.
  • Ali, Mina, et al. (författare)
  • The multiple myeloma risk allele at 5q15 lowers ELL2 expression and increases ribosomal gene expression
  • 2018
  • Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 1649-
  • Tidskriftsartikel (refereegranskat)abstract
    • Recently, we identified ELL2 as a susceptibility gene for multiple myeloma (MM). To understand its mechanism of action, we performed expression quantitative trait locus analysis in CD138+ plasma cells from 1630 MM patients from four populations. We show that the MM risk allele lowers ELL2 expression in these cells (Pcombined = 2.5 × 10−27; βcombined = −0.24 SD), but not in peripheral blood or other tissues. Consistent with this, several variants representing the MM risk allele map to regulatory genomic regions, and three yield reduced transcriptional activity in plasmocytoma cell lines. One of these (rs3777189-C) co-locates with the best-supported lead variants for ELL2 expression and MM risk, and reduces binding of MAFF/G/K family transcription factors. Moreover, further analysis reveals that the MM risk allele associates with upregulation of gene sets related to ribosome biogenesis, and knockout/knockdown and rescue experiments in plasmocytoma cell lines support a cause–effect relationship. Our results provide mechanistic insight into MM predisposition.
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12.
  • Barillot, T., et al. (författare)
  • Angular asymmetry and attosecond time delay from the giant plasmon resonance in C60 photoionization
  • 2015
  • Ingår i: Physical Review A. Atomic, Molecular, and Optical Physics. - 1050-2947 .- 1094-1622. ; 91
  • Tidskriftsartikel (refereegranskat)abstract
    • This combined experimental and theoretical study demonstrates that the surface plasmon resonance in C 60 alters the valence photoemission quantum phase, resulting in strong effects in the photoelectron angular distribution and emission time delay. Electron momentum imaging spectroscopy is used to measure the photoelectron angular distribution asymmetry parameter that agrees well with our calculations from the time-dependent local density approximation (TDLDA). Significant structure in the valence photoemission time delay is simultaneously calculated by TDLDA over the plasmon active energies. Results reveal a unified spatial and temporal asymmetry pattern driven by the plasmon resonance and offer a sensitive probe of electron correlation. A semiclassical approach facilitates further insights into this link that can be generalized and applied to other molecular systems and nanometer-sized metallic materials exhibiting plasmon resonances.
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13.
  • Barillot, T., et al. (författare)
  • Attosecond time delays in C-60 valence photoemissions at the giant plasmon
  • 2015
  • Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6596 .- 1742-6588. ; 635, s. 112074-112074
  • Konferensbidrag (refereegranskat)abstract
    • We perform time-dependent local density functional calculations of the time delay in C-60 HOMO and HOMO-1 photoionization at giant plasmon energies. A semiclassical model is used to develop further insights.
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14.
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15.
  • Ehnhage, A, et al. (författare)
  • Corrigendum
  • 2016
  • Ingår i: Acta oto-laryngologica. - : Informa UK Limited. - 1651-2251 .- 0001-6489. ; 136:9, s. 982-982
  • Tidskriftsartikel (refereegranskat)
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16.
  • Engström, Gunnar, et al. (författare)
  • The Swedish CArdioPulmonary BioImage Study : objectives and design
  • 2015
  • Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 278:6, s. 645-659
  • Tidskriftsartikel (refereegranskat)abstract
    • Cardiopulmonary diseases are major causes of death worldwide, but currently recommended strategies for diagnosis and prevention may be outdated because of recent changes in risk factor patterns. The Swedish CArdioPulmonarybioImage Study (SCAPIS) combines the use of new imaging technologies, advances in large-scale 'omics' and epidemiological analyses to extensively characterize a Swedish cohort of 30 000 men and women aged between 50 and 64 years. The information obtained will be used to improve risk prediction of cardiopulmonary diseases and optimize the ability to study disease mechanisms. A comprehensive pilot study in 1111 individuals, which was completed in 2012, demonstrated the feasibility and financial and ethical consequences of SCAPIS. Recruitment to the national, multicentre study has recently started.
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18.
  • Gering, E., et al. (författare)
  • Mixed ancestry and admixture in Kauai's feral chickens: invasion of domestic genes into ancient Red Junglefowl reserviors
  • 2015
  • Ingår i: Molecular Ecology. - : John Wiley & Sons. - 0962-1083 .- 1365-294X. ; 24:9, s. 2112-2124
  • Tidskriftsartikel (refereegranskat)abstract
    • A major goal of invasion genetics is to determine how establishment histories shape non-native organisms' genotypes and phenotypes. While domesticated species commonly escape cultivation to invade feral habitats, few studies have examined how this process shapes feral gene pools and traits. We collected genomic and phenotypic data from feral chickens (Gallus gallus) on the Hawaiian island of Kauai to (i) ascertain their origins and (ii) measure standing variation in feral genomes, morphology and behaviour. Mitochondrial phylogenies (D-loop & whole Mt genome) revealed two divergent clades within our samples. The rare clade also contains sequences from Red Junglefowl (the domestic chicken's progenitor) and ancient DNA sequences from Kauai that predate European contact. This lineage appears to have been dispersed into the east Pacific by ancient Polynesian colonists. The more prevalent MtDNA clade occurs worldwide and includes domesticated breeds developed recently in Europe that are farmed within Hawaii. We hypothesize this lineage originates from recently feralized livestock and found supporting evidence for increased G. gallus density on Kauai within the last few decades. SNPs obtained from whole-genome sequencing were consistent with historic admixture between Kauai's divergent (G. gallus) lineages. Additionally, analyses of plumage, skin colour and vocalizations revealed that Kauai birds' behaviours and morphologies overlap with those of domestic chickens and Red Junglefowl, suggesting hybrid origins. Together, our data support the hypotheses that (i) Kauai's feral G. gallus descend from recent invasion(s) of domestic chickens into an ancient Red Junglefowl reservoir and (ii) feral chickens exhibit greater phenotypic diversity than candidate source populations. These findings complicate management objectives for Pacific feral chickens, while highlighting the potential of this and other feral systems for evolutionary studies of invasions.
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23.
  • Larsen, M. H., et al. (författare)
  • Reduced rearing density increases postrelease migration success of Atlantic salmon (Salmo salar) smolts
  • 2016
  • Ingår i: Canadian Journal of Fisheries and Aquatic Sciences. - : Canadian Science Publishing. - 0706-652X .- 1205-7533. ; 73:5, s. 804-810
  • Tidskriftsartikel (refereegranskat)abstract
    • The overall aim of this study was to investigate the effect of rearing density on the postrelease survival of Atlantic salmon (Salmo salar) smolts during seaward migration. Fish were either reared at conventional hatchery density or at one-third of conventional density. Three hundred 1-year-old smolts from each density treatment were individually tagged with passive integrated transponder tags and released 3.2 km upstream of a stationary antenna array in a natural stream. There were no significant differences in length, body mass, or condition between fish from the two density treatments during rearing in the hatchery. However, individuals reared at reduced density had less eroded dorsal fins and opercula relative to those from the high-density treatment. In the stream, the downstream migration success was 16% higher for fish reared at reduced density than for conspecifics kept at high density, but the timing of migration was similar for both groups. These novel results suggest that conventionally high rearing densities may reduce welfare and the postrelease migration success of hatchery-reared Atlantic salmon.
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24.
  • Manschwetus, B., et al. (författare)
  • Two-photon double ionization of neon studied with intense attosecond pulse trains
  • 2016
  • Ingår i: International Conference on Ultrafast Phenomena, UP 2016. - 9781943580187 ; Part F20-UP 2016
  • Konferensbidrag (refereegranskat)abstract
    • We focused an intense attosecond pulse train into a neon gas target and observed Ne2+ resulting from two-photon double ionization. By modifying the photon spectrum we find that the process is dominated by the sequential ionization via the Ne+ ion.
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25.
  • Manschwetus, B., et al. (författare)
  • Two-photon double ionization of neon using an intense attosecond pulse train
  • 2016
  • Ingår i: Physical Review A. - : American Physical Society (APS). - 2469-9926 .- 2469-9934. ; 93:6
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a demonstration of two-photon double ionization of neon using an intense extreme ultraviolet (XUV) attosecond pulse train (APT) in a photon energy regime where both direct and sequential mechanisms are allowed. For an APT generated through high-order harmonic generation (HHG) in argon we achieve a total pulse energy close to 1μJ, a central energy of 35 eV, and a total bandwidth of ∼30 eV. The APT is focused by broadband optics in a neon gas target to an intensity of 3×1012Wcm−2. By tuning the photon energy across the threshold for the sequential process the double ionization signal can be turned on and off, indicating that the two-photon double ionization predominantly occurs through a sequential process. The demonstrated performance opens up possibilities for future XUV-XUV pump-probe experiments with attosecond temporal resolution in a photon energy range where it is possible to unravel the dynamics behind direct versus sequential double ionization and the associated electron correlation effects.
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26.
  • Nyholm, Tufve, et al. (författare)
  • A national approach for automated collection of standardized and population-based radiation therapy data in Sweden
  • 2016
  • Ingår i: Radiotherapy and Oncology. - : Elsevier BV. - 0167-8140 .- 1879-0887. ; 119:2, s. 344-350
  • Tidskriftsartikel (refereegranskat)abstract
    • Purpose: To develop an infrastructure for structured and automated collection of interoperable radiation therapy (RT) data into a national clinical quality registry. Materials and methods: The present study was initiated in 2012 with the participation of seven of the 15 hospital departments delivering RT in Sweden. A national RT nomenclature and a database for structured unified storage of RT data at each site (Medical Information Quality Archive, MIQA) have been developed. Aggregated data from the MIQA databases are sent to a national RT registry located on the same IT platform (INCA) as the national clinical cancer registries. Results: The suggested naming convention has to date been integrated into the clinical workflow at 12 of 15 sites, and MIQA is installed at six of these. Involvement of the remaining 3/15 RT departments is ongoing, and they are expected to be part of the infrastructure by 2016. RT data collection from ARIA (R), Mosaiq (R), Eclipse (TM), and Oncentra (R) is supported. Manual curation of RT-structure information is needed for approximately 10% of target volumes, but rarely for normal tissue structures, demonstrating a good compliance to the RT nomenclature. Aggregated dose/volume descriptors are calculated based on the information in MIQA and sent to INCA using a dedicated service (MIQA2INCA). Correct linkage of data for each patient to the clinical cancer registries on the INCA platform is assured by the unique Swedish personal identity number. Conclusions: An infrastructure for structured and automated prospective collection of syntactically inter operable RT data into a national clinical quality registry for RT data is under implementation. Future developments include adapting MIQA to other treatment modalities (e.g. proton therapy and brachytherapy) and finding strategies to harmonize structure delineations. How the RT registry should comply with domain-specific ontologies such as the Radiation Oncology Ontology (ROO) is under discussion.
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27.
  • Näslund, Joacim, 1985, et al. (författare)
  • Environment-dependent plasticity and ontogenetic changes in the brain of hatchery-reared Atlantic salmon
  • 2017
  • Ingår i: Journal of Zoology. - : Wiley. - 0952-8369 .- 1469-7998. ; 301:1, s. 75-82
  • Tidskriftsartikel (refereegranskat)abstract
    • Lowered rearing density has repeatedly been shown to increase the performance of hatchery-reared salmonids stocked into natural environments. One possible mechanism for this pattern could be that lower densities enhance brain development, which has been shown to be the case in other hatchery enhancement strategies, like environmental enrichment. Here, we investigated the size of the brain in hatchery-reared Atlantic salmon Salmo salar kept at standard (high) and reduced (low) tank densities. In contrast to our predictions, we found that fish reared at high density had larger dry mass of cerebellum and telencephalon, correcting for body size. No differences were detected for total brain mass. Furthermore, we found that the relative size of both telencephalon and cerebellum, in relation to total brain mass, changed with body size. Cerebellum increased in relative size with increased body size, while the opposite pattern was observed for telencephalon. Overall, these results reveal substantial brain plasticity depending on the surrounding environment as well as ontogenetic adaptive changes in the brain of the Atlantic salmon.
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28.
  • Orgel, Csilla, et al. (författare)
  • Gridmapping the Northern Plains of Mars: A New Overview of Recent Water‐ and Ice‐Related Landforms in Acidalia Planitia.
  • 2019
  • Ingår i: Journal of Geophysical Research - Planets. - 2169-9100. ; 124:2, s. 454-82
  • Tidskriftsartikel (refereegranskat)abstract
    • We used a grid‐mapping technique to analyze the distribution of 13 water‐ and ice‐related landforms in Acidalia Planitia as part of a joint effort to study the three main basins in the northern lowlands of Mars, that is, Acidalia, Utopia, and Arcadia Planitiae. The landforms were mapped at full Context Camera resolution along a 300‐km‐wide strip from 20°N to 84°N. We identified four landform assemblages: (1) Geologically recent polar cap (massive ice), which superposes the latitude‐dependent mantle (LDM) (LA1); (2) ice‐related landforms, such as LDM, textured terrain, small‐scale polygons, scalloped terrain, large‐scale viscous flow features, and gullies, which have an overlapping distribution (LA2); (3) surface features possibly related to water and subsurface sediment mobilization (LA3; kilometer‐scale polygons, large pitted mounds, small pitted mounds, thumbprint terrain); and (4) irregularly shaped pits with raised rims on equator‐facing slopes. Pits are likely the result of an energetic release of volatiles (H2O, CO2, and CH4), rather than impact‐, volcanism‐, or wind‐related processes. LDM occurs ubiquitously from 44°N to 78°N in Acidalia Planitia. Various observations suggest an origin of air fall deposition of LDM, which contains less ice in the uppermost tens of meters in Acidalia Planitia than in Arcadia and Utopia Planitiae. However, LDM may be thicker and more extended in the past in Acidalia Planitia. The transition between LDM‐free terrain and LDM is situated further north than in Utopia and Arcadia Planitiae, suggesting different past and/or present climatic conditions among the main basins in the northern lowlands.
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29.
  • Ramsdale, J. D., et al. (författare)
  • Grid-based mapping: A method for rapidly determining the spatial distributions of small features over very large areas
  • 2017
  • Ingår i: Planetary and Space Science. - : Elsevier BV. - 0032-0633. ; 140, s. 49-61
  • Tidskriftsartikel (refereegranskat)abstract
    • The increased volume, spatial resolution, and areal coverage of high-resolution images of Mars over the past 15 years have led to an increased quantity and variety of small-scale landform identifications. Though many such landforms are too small to represent individually on regional-scale maps, determining their presence or absence across large areas helps form the observational basis for developing hypotheses on the geological nature and environmental history of a study area. The combination of improved spatial resolution and near-continuous coverage significantly increases the time required to analyse the data. This becomes problematic when attempting regional or global-scale studies of metre and decametre-scale landforms. Here, we describe an approach for mapping small features (from decimetre to kilometre scale) across large areas, formulated for a project to study the northern plains of Mars, and provide context on how this method was developed and how it can be implemented. Rather than. "mapping" with points and polygons, grid-based mapping uses a "tick box" approach to efficiently record the locations of specific landforms (we use an example suite of glacial landforms; including viscous flow features, the latitude dependant mantle and polygonised ground). A grid of squares (e.g. 20 km by 20 km) is created over the mapping area. Then the basemap data are systematically examined, grid-square by grid-square at full resolution, in order to identify the landforms while recording the presence or absence of selected landforms in each grid-square to determine spatial distributions. The result is a series of grids recording the distribution of all the mapped landforms across the study area. In some ways, these are equivalent to raster images, as they show a continuous distribution-field of the various landforms across a defined (rectangular, in most cases) area. When overlain on context maps, these form a coarse, digital landform map. We find that grid-based mapping provides an efficient solution to the problems of mapping small landforms over large areas, by providing a consistent and standardised approach to spatial data collection. The simplicity of the grid-based mapping approach makes it extremely scalable and workable for group efforts, requiring minimal user experience and producing consistent and repeatable results. The discrete nature of the datasets, simplicity of approach, and divisibility of tasks, open up the possibility for citizen science in which crowdsourcing large grid based mapping areas could be applied.
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30.
  • Ramsdale, Jason D., et al. (författare)
  • Gridmapping the northern plains of Mars: Geomorphological, Radar and Water-Equivalent Hydrogen results from Arcadia Plantia.
  • 2019
  • Ingår i: Journal of Geophysical Research - Planets. - 2169-9100. ; 124:2, s. 504-27
  • Tidskriftsartikel (refereegranskat)abstract
    • A project of mapping ice‐related landforms was undertaken to understand the role of subsurface ice in the northern plains. This work is the first continuous regional mapping from CTX (ConTeXt Camera, 6 m/pixel; Malin et al., 2007) imagery in Arcadia Planitia along a strip 300 km across stretching from 30°N to 80°N centered on the 170°W line of longitude. The distribution and morphotypes of these landforms were used to understand the permafrost cryolithology. The mantled and textured signatures occur almost ubiquitously between 35°N and 78°N and have a positive spatial correlation with inferred ice stability based on thermal modeling, neutron spectroscopy, and radar data. The degradational features into the LDM (latitude‐dependent mantle) include pits, scallops, and 100‐m polygons and provide supporting evidence for subsurface ice and volatile loss between 35 and 70°N in Arcadia with the mantle between 70 and 78°N appearing much more intact. Pitted terrain appears to be much more pervasive in Arcadia than in Acidalia and Utopia suggesting that the Arcadia study area had more widespread near‐surface subsurface ice and thus was more susceptible to pitting or that the ice was less well buried by sediments. Correlations with ice stability models suggest that lack of pits north of 65–70°N could indicate a relatively young age (~1 Ma); however, this could also be explained through regional variations in degradation rates. The deposition of the LDM is consistent with an air fall hypothesis; however, there appears to be substantial evidence for fluvial processes in southern Arcadia with older, underlying processes being equally dominant with the LDM and degradation thereof in shaping the landscape.
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31.
  • Serviss, J. T., et al. (författare)
  • An antisense RNA capable of modulating the expression of the tumor suppressor microRNA-34a
  • 2018
  • Ingår i: Cell Death & Disease. - : Springer Science and Business Media LLC. - 2041-4889. ; 9:7
  • Tidskriftsartikel (refereegranskat)abstract
    • The microRNA-34a is a well-studied tumor suppressor microRNA (miRNA) and a direct downstream target of TP53 with roles in several pathways associated with oncogenesis, such as proliferation, cellular growth, and differentiation. Due to its broad tumor suppressive activity, it is not surprising that miR34a expression is altered in a wide variety of solid tumors and hematological malignancies. However, the mechanisms by which miR34a is regulated in these cancers is largely unknown. In this study, we find that a long noncoding RNA transcribed antisense to the miR34a host gene, is critical for miR34a expression and mediation of its cellular functions in multiple types of human cancer. We name this long noncoding RNA lncTAM34a, and characterize its ability to facilitate miR34a expression under different types of cellular stress in both TP53-deficient and wild-type settings.
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32.
  • Singh, Vinayak, et al. (författare)
  • Identification of aminopyrimidine-sulfonamides as potent modulators of Wag31-mediated cell elongation in mycobacteria.
  • 2017
  • Ingår i: Molecular Microbiology. - : Wiley. - 0950-382X .- 1365-2958. ; 103:1, s. 13-25
  • Tidskriftsartikel (refereegranskat)abstract
    • There is an urgent need to discover new anti-tubercular agents with novel mechanisms of action in order to tackle the scourge of drug-resistant tuberculosis. Here, we report the identification of such a molecule - an AminoPYrimidine-Sulfonamide (APYS1) that has potent, bactericidal activity against M. tuberculosis. Mutations in APYS1-resistant M. tuberculosis mapped exclusively to wag31, a gene that encodes a scaffolding protein thought to orchestrate cell elongation. Recombineering confirmed that a Gln201Arg mutation in Wag31 was sufficient to cause resistance to APYS1, however, neither overexpression nor conditional depletion of wag31 impacted M. tuberculosis susceptibility to this compound. In contrast, expression of the wildtype allele of wag31 in APYS1-resistant M. tuberculosis was dominant and restored susceptibility to APYS1 to wildtype levels. Time-lapse imaging and scanning electron microscopy revealed that APYS1 caused gross malformation of the old pole of M. tuberculosis, with eventual lysis. These effects resembled the morphological changes observed following transcriptional silencing of wag31 in M. tuberculosis. These data show that Wag31 is likely not the direct target of APYS1, but the striking phenotypic similarity between APYS1 exposure and genetic depletion of Wag31 in M. tuberculosis suggests that APYS1 might indirectly affect Wag31 through an as yet unknown mechanism.
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33.
  • Tervaniemi, MH, et al. (författare)
  • NOD-like receptor signaling and inflammasome-related pathways are highlighted in psoriatic epidermis
  • 2016
  • Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6, s. 22745-
  • Tidskriftsartikel (refereegranskat)abstract
    • Psoriatic skin differs distinctly from normal skin by its thickened epidermis. Most gene expression comparisons utilize full-thickness biopsies, with substantial amount of dermis. We assayed the transcriptomes of normal, lesional and non-lesional psoriatic epidermis, sampled as split-thickness skin grafts, with 5′-end RNA sequencing. We found that psoriatic epidermis contains more mRNA per total RNA than controls and took this into account in the bioinformatic analysis. The approach highlighted innate immunity-related pathways in psoriasis, including NOD-like receptor (NLR) signaling and inflammasome activation. We demonstrated that the NLR signaling genes NOD2, PYCARD, CARD6 and IFI16 are upregulated in psoriatic epidermis and strengthened these findings by protein expression. Interestingly, PYCARD, the key component of the inflammasome, showed an altered expression pattern in the lesional epidermis. The profiling of non-lesional skin highlighted PSORS4 and mitochondrially encoded transcripts, suggesting that their gene expression is altered already before the development of lesions. Our data suggest that all components needed for the active inflammasome are present in the keratinocytes of psoriatic skin. The characterization of inflammasome pathways provides further opportunities for therapy. Complementing previous transcriptome studies, our approach gives deeper insight into the gene regulation in psoriatic epidermis.
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34.
  • Vilsboll, T., et al. (författare)
  • Dapagliflozin Plus Saxagliptin Add-on Therapy Compared With Insulin in Patients With Type 2 Diabetes Poorly Controlled by Metformin With or Without Sulfonylurea Therapy: A Randomized Clinical Trial
  • 2019
  • Ingår i: Diabetes Care. - : American Diabetes Association. - 0149-5992 .- 1935-5548. ; 42:8, s. 1464-1472
  • Tidskriftsartikel (refereegranskat)abstract
    • OBJECTIVE This study evaluated whether an oral combination of a sodium-glucose cotransporter 2 inhibitor and a dipeptidyl peptidase 4 inhibitor achieved glycemic control similar to basal insulin in patients with type 2 diabetes, poorly controlled with metformin, without increasing hypoglycemia or body weight. RESEARCH DESIGN AND METHODS In a multinational, open-label, randomized, phase 3 trial ( reg. no. ), adults with type 2 diabetes inadequately controlled on metformin, with or without sulfonylurea, were randomized (1:1) to receive dapagliflozin (DAPA) plus saxagliptin (SAXA) or titrated insulin glargine (INS). The primary end point was change in glycated hemoglobin A(1c) (HbA(1c)) from baseline to week 24. DAPA + SAXA treatment was tested for noninferiority versus INS. RESULTS The efficacy data set included 643 patients (mean +/- SD HbA(1c), 9.1 +/- 1.0% [75 +/- 11 mmol/mol]). At week 24, DAPA + SAXA treatment versus INS resulted in noninferior reductions in HbA(1c) (adjusted mean +/- SE change, -1.7 +/- 0.1% vs. -1.5 +/- 0.1% [18.3 +/- 0.7 mmol/mol vs. 16.8 +/- 0.7 mmol/mol]; P = 0.118), significantly different body weight change (between-group difference, -3.64 kg [95% CI -4.20 to -3.09]; P < 0.001), fewer patients with confirmed hypoglycemia (21.3% vs. 38.4%, P < 0.001), more patients achieving HbA(1c) <7.0% (53 mmol/mol) without hypoglycemia (20.9% vs. 13.1%, P = 0.008), and a similar proportion of patients achieving HbA(1c) <7.0% (33.2% vs. 33.5%, P = 0.924). Mean reductions in 24-h glucose measurements from baseline to week 2 were greater with DAPA + SAXA than with INS (P < 0.0001). No patients in the DAPA + SAXA group and three patients (0.9%) in the INS group experienced severe hypoglycemia. CONCLUSIONS Adding DAPA + SAXA to insulin-naive patients with poorly controlled type 2 diabetes achieved similar glycemic control, a lower risk of hypoglycemia, and a clinically relevant body weight difference compared with basal INS.
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35.
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36.
  • Warmlander, Sebastian K. T. S., et al. (författare)
  • Amulets rather than iron bars. Metallographic analysis indicates uneven material quality in Vendel Period iron rings from Aselby in Stora Tuna parish, Dalecarlia
  • 2018
  • Ingår i: Fornvännen. - : Royal Academy Letters, History & Antiquities. - 0015-7813 .- 1404-9430. ; 113:1, s. 1-6
  • Tidskriftsartikel (refereegranskat)abstract
    • 29 iron rings with diameters between 9 and 15 cm were excavated in 1989 at a Vendel Period settlement site with a longhouse, located at Aselby in Dalecarlia, Sweden. Most of the rings had between one and three smaller rings attached. Rings of this type and size are fairly common at Scandinavian Vendel and Viking Period sites - settlements, cemeteries and cult precincts - but their function remains debated. The rings from Aselby have been interpreted as iron/steel bars, to be used or traded as raw material for e.g. weapons production. Previous metallurgical analysis of one Aselby ring showed it to consist of somewhat uneven but still decent-quality carbon steel. General conclusions should however not be drawn from a single observation. Here, we have sampled six Aselby rings for metallographic examination of the cross-sections. The material quality and carbon content of the sampled rings were found to be very uneven, and relatively large inclusions of unworked slag were common. We conclude that the rings were not bars of raw material. Instead, they may have been amulet rings, intended for ritual use. If so, our results suggest that the material properties of amulet rings may have been less important during rituals it may have sufficed that the rings had the right shape.
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37.
  • Watz, Johan, 1977-, et al. (författare)
  • Wood addition in the hatchery and river environments affects post-release performance of overwintering brown trout
  • 2019
  • Ingår i: Freshwater Biology. - : Wiley. - 0046-5070 .- 1365-2427. ; 64:1, s. 71-80
  • Tidskriftsartikel (refereegranskat)abstract
    • Habitat structural complexity affects the behaviour and physiology of individuals, and responses to the environment can be immediate or influence performance later in life through delayed effects. Here, we investigated how structural enrichment, both pre-release in the hatchery rearing environment and post-release in the wild, influenced winter growth and site fidelity of brown trout stocked into side channels of a regulated river. Experiencing structural enrichment in the rearing environment during 3 months in autumn had no pre-release effect on growth, but a delayed positive effect after release during the subsequent winter. Moreover, trout recaptured in wood-treated sections of the side channels had grown more than trout recaptured in control sections. Wood enrichment in the side channels also increased overwinter site fidelity. These results show that adding structure during a relatively short period may alter growth trajectories, and adding wood to side channels is a cost-effective method to enhance winter habitat carrying capacity for juvenile salmonids in regulated rivers.
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38.
  • Went, M, et al. (författare)
  • Author Correction: Identification of multiple risk loci and regulatory mechanisms influencing susceptibility to multiple myeloma
  • 2019
  • Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 213-
  • Tidskriftsartikel (refereegranskat)abstract
    • The original version of this Article contained an error in the spelling of a member of the PRACTICAL Consortium, Manuela Gago-Dominguez, which was incorrectly given as Manuela Gago Dominguez. This has now been corrected in both the PDF and HTML versions of the Article. Furthermore, in the original HTML version of this Article, the order of authors within the author list was incorrect. The PRACTICAL consortium was incorrectly listed after Richard S. Houlston and should have been listed after Nora Pashayan. This error has been corrected in the HTML version of the Article; the PDF version was correct at the time of publication.
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39.
  • Went, M, et al. (författare)
  • Identification of multiple risk loci and regulatory mechanisms influencing susceptibility to multiple myeloma
  • 2018
  • Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9:1, s. 3707-
  • Tidskriftsartikel (refereegranskat)abstract
    • Genome-wide association studies (GWAS) have transformed our understanding of susceptibility to multiple myeloma (MM), but much of the heritability remains unexplained. We report a new GWAS, a meta-analysis with previous GWAS and a replication series, totalling 9974 MM cases and 247,556 controls of European ancestry. Collectively, these data provide evidence for six new MM risk loci, bringing the total number to 23. Integration of information from gene expression, epigenetic profiling and in situ Hi-C data for the 23 risk loci implicate disruption of developmental transcriptional regulators as a basis of MM susceptibility, compatible with altered B-cell differentiation as a key mechanism. Dysregulation of autophagy/apoptosis and cell cycle signalling feature as recurrently perturbed pathways. Our findings provide further insight into the biological basis of MM.
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40.
  • Zetterberg, Fredrik R., et al. (författare)
  • Monosaccharide Derivatives with Low-Nanomolar Lectin Affinity and High Selectivity Based on Combined Fluorine-Amide, Phenyl-Arginine, Sulfur-π, and Halogen Bond Interactions
  • 2018
  • Ingår i: ChemMedChem. - : Wiley. - 1860-7179. ; 13:2, s. 133-137
  • Tidskriftsartikel (refereegranskat)abstract
    • The design of small and high-affinity lectin inhibitors remains a major challenge because the natural ligand binding sites of lectin are often shallow and have polar character. Herein we report that derivatizing galactose with un-natural structural elements that form multiple non-natural lectin-ligand interactions (orthogonal multipolar fluorine-amide, phenyl-arginine, sulfur-π, and halogen bond) can provide inhibitors with extraordinary affinity (low nanomolar) for the model lectin, galectin-3, which is more than five orders of magnitude higher than the parent galactose; moreover, is selective over other galectins.
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41.
  • Zhang, Y. H., et al. (författare)
  • Computed tomography volumetry of esophageal cancer - the role of semiautomatic assessment
  • 2019
  • Ingår i: Bmc Medical Imaging. - : Springer Science and Business Media LLC. - 1471-2342. ; 19
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundThe clinical and research value of Computed Tomography (CT) volumetry of esophageal cancer tumor size remains controversial. Development in CT technique and image analysis has made CT volumetry less cumbersome and it has gained renewed attention. The aim of this study was to assess esophageal tumor volume by semi-automatic measurements as compared to manual.MethodsA total of 23 esophageal cancer patients (median age 65, range 51-71), undergoing CT in the portal-venous phase for tumor staging, were retrospectively included between 2007 and 2012. One radiology resident and one consultant radiologist measured the tumor volume by semiautomatic segmentation and manual segmentation. Reproducibility of the respective measurements was assessed by intraclass correlation coefficients (ICC) and by average deviation from mean.ResultsMean tumor volume was 46ml (range 5-137ml) using manual segmentation and 42ml (range 3-111ml) using semiautomatic segmentation. Semiautomatic measurement provided better inter-observer agreement than traditional manual segmentation. The ICC was significantly higher for semiautomatic segmentation in comparison to manual segmentation (0.86, 0.56, p<0.01). The average absolute percentage difference from mean was reduced from 24 to 14% (p<0.001) when using semiautomatic segmentation.ConclusionsSemiautomatic analysis outperforms manual analysis for assessment of esophageal tumor volume, improving reproducibility.
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