| 1. |
- Bouget, D., et al.
(författare)
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Preoperative Brain Tumor Imaging: Models and Software for Segmentation and Standardized Reporting
- 2022
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Ingår i: Frontiers in Neurology. - : Frontiers Media SA. - 1664-2295. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- For patients suffering from brain tumor, prognosis estimation and treatment decisions are made by a multidisciplinary team based on a set of preoperative MR scans. Currently, the lack of standardized and automatic methods for tumor detection and generation of clinical reports, incorporating a wide range of tumor characteristics, represents a major hurdle. In this study, we investigate the most occurring brain tumor types: glioblastomas, lower grade gliomas, meningiomas, and metastases, through four cohorts of up to 4,000 patients. Tumor segmentation models were trained using the AGU-Net architecture with different preprocessing steps and protocols. Segmentation performances were assessed in-depth using a wide-range of voxel and patient-wise metrics covering volume, distance, and probabilistic aspects. Finally, two software solutions have been developed, enabling an easy use of the trained models and standardized generation of clinical reports: Raidionics and Raidionics-Slicer. Segmentation performances were quite homogeneous across the four different brain tumor types, with an average true positive Dice ranging between 80 and 90%, patient-wise recall between 88 and 98%, and patient-wise precision around 95%. In conjunction to Dice, the identified most relevant other metrics were the relative absolute volume difference, the variation of information, and the Hausdorff, Mahalanobis, and object average symmetric surface distances. With our Raidionics software, running on a desktop computer with CPU support, tumor segmentation can be performed in 16-54 s depending on the dimensions of the MRI volume. For the generation of a standardized clinical report, including the tumor segmentation and features computation, 5-15 min are necessary. All trained models have been made open-access together with the source code for both software solutions and validation metrics computation. In the future, a method to convert results from a set of metrics into a final single score would be highly desirable for easier ranking across trained models. In addition, an automatic classification of the brain tumor type would be necessary to replace manual user input. Finally, the inclusion of post-operative segmentation in both software solutions will be key for generating complete post-operative standardized clinical reports.
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| 2. |
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| 3. |
- Jakola, Asgeir Store, et al.
(författare)
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Quantitative texture analysis in the prediction of IDH status in low-grade gliomas.
- 2018
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Ingår i: Clinical neurology and neurosurgery. - : Elsevier BV. - 1872-6968 .- 0303-8467. ; 164, s. 114-120
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Tidskriftsartikel (refereegranskat)abstract
- Molecular markers provide valuable information about treatment response and prognosis in patients with low-grade gliomas (LGG). In order to make this important information available prior to surgery the aim of this study was to explore if molecular status in LGG can be discriminated by preoperative magnetic resonance imaging (MRI).All patients with histopathologically confirmed LGG with available molecular status who had undergone a preoperative standard clinical MRI protocol using a 3T Siemens Skyra scanner during 2008-2015 were retrospectively identified. Based on Haralick texture parameters and the segmented LGG FLAIR volume we explored if it was possible to predict molecular status.In total 25 patients (nine women, average age 44) fulfilled the inclusion parameters. The textural parameter homogeneity could discriminate between LGG patients with IDH mutation (0.12, IQR 0.10-0.15) and IDH wild type (0.07, IQR 0.06-0.09, p=0.005). None of the other four analyzed texture parameters (energy, entropy, correlation and inertia) were associated with molecular status. Using ROC curves, the area under curve for predicting IDH mutation was 0.905 for homogeneity, 0.840 for tumor volume and 0.940 for the combined parameters of tumor volume and homogeneity. We could not predict molecular status using the four other chosen texture parameters (energy, entropy, correlation and inertia). Further, we could not separate LGG with IDH mutation with or without 1p19q codeletion.In this preliminary study using Haralick texture parameters based on preoperative clinical FLAIR sequence, the homogeneity parameter could separate IDH mutated LGG from IDH wild type LGG. Combined with tumor volume, these diagnostic properties seem promising.
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| 4. |
- Jones, Eleanor P., et al.
(författare)
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Norwegian house mice (Mus musculus musculus/domesticus) : distributions, routes of colonization and patterns of hybridization
- 2010
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Ingår i: Molecular Ecology. - 0962-1083 .- 1365-294X. ; 19:23, s. 5252-5264
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Tidskriftsartikel (refereegranskat)abstract
- We investigated the distributions and routes of colonization of two commensal subspecies of house mouse in Norway: Mus musculus domesticus and M. m. musculus. Five nuclear markers (Abpa, D11 cenB2, Btk, SMCY and Zfy2) and a morphological feature (tail length) were used to differentiate the two subspecies and assess their distributions, and mitochondrial (mt) D-loop sequences helped to elucidate their colonization history. M. m. domesticus is the more widespread of the two subspecies, occupying the western and southern coast of Norway, while M. m. musculus is found along Norway's southeastern coast and east from there to Sweden. Two sections of the hybrid zone between the two subspecies were localized in Norway. However, hybrid forms also occur well away from that hybrid zone, the most prevalent of which are mice with a M. m. musculus-type Y chromosome and an otherwise M. m. domesticus genome. MtDNA D-loop sequences of the mice revealed a complex phylogeography within M. m. domesticus, reflecting passive human transport to Norway, probably during the Viking period. M. m. musculus may have colonized earlier. If so, that leaves open the possibility that M. m. domesticus replaced M. m. musculus from much of Norway, with the widely distributed hybrids a relict of this process. Overall, the effects of hybridization are evident in house mice throughout Norway.
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| 5. |
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| 6. |
- McLinden, C. A., et al.
(författare)
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OSIRIS: A Decade of Scattered Light
- 2012
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Ingår i: Bulletin of the American Meteorological Society. - 0003-0007 .- 1520-0477. ; 93:12, s. 1845-1863
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Tidskriftsartikel (refereegranskat)abstract
- Into year 11 of a 2-yr mission, OSIRIS is redefining how limb-scattered sunlight can be used to probe the atmosphere, even into the upper troposphere.
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| 7. |
- Nilsson, Robert, et al.
(författare)
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New pulsating white dwarfs in cataclysmic variables
- 2006
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 1365-2966 .- 1745-3925 .- 1745-3933. ; 370:1, s. 56-60, s. 49-61
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Tidskriftsartikel (refereegranskat)abstract
- The number of discovered non-radially pulsating white dwarfs (WDs) in cataclysmic variables (CVs) is increasing rapidly by the aid of the Sloan Digital Sky Survey (SDSS). We performed photometric observations of two additional objects, SDSS J133941.11+484727.5 (SDSS 1339), independently discovered as a pulsator by Gansicke et al., and SDSS J151413.72+454911.9, which we identified as a CV/ZZ Ceti hybrid. In this Letter we present the results of the remote observations of these targets performed with the Nordic Optical Telescope (NOT) during the Nordic-Baltic Research School at Moletai Observatory, and follow-up observations executed by NOT in service mode. We also present three candidates we found to be non-pulsating. The results of our observations show that the main pulsation frequencies agree with those found in previous CV/ZZ Ceti hybrids, but specifically for SDSS 1339 the principal period differs slightly between individual observations and also from the recent independent observation by Gansicke et al. Analysis of SDSS colour data for the small sample of pulsating and non-pulsating CV/ZZ Ceti hybrids found so far seems to indicate that the r - i colour could be a good marker for the instability strip of this class of pulsating WDs.
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| 8. |
- Sioris, C. E., et al.
(författare)
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The atmospheric limb sounding satellite (ALISS)
- 2014
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Ingår i: Proceedings of the International Astronautical Congress, IAC. - 0074-1795. - 9781634399869 ; 4, s. 2382-2392
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Konferensbidrag (refereegranskat)abstract
- The Atmospheric Limb Sounding Satellite (ALISS) is a joint Canadian-Swedish concept that is currently under study by agencies, industrial partners and academic institutions in both countries. Launch is not anticipated before late 2020. ALISS has significant heritage, resembling the current Odin mission in terms of some of the countries involved and the types of instruments. However, ALISS will have a focus on the upper troposphere in addition to Odin's primarily stratospheric focus. The ALISS mission has objectives relating to climate-chemistry coupling, UV radiation, dynamics, atmospheric composition in the upper troposphere and lower stratosphere, and in conjunction with nadir sensors, air quality, by virtue of the array of key atmospheric constituents that it will measure with an unprecedented combination of vertical and horizontal resolution for satellite-borne instruments. ALISS consists of four atmospheric limb remote sensing instruments. Three of these have space heritage and are: the Canadian-designed Atmospheric Tomography System (CATS) that is a derivative of the highly successful Optical Spectrograph and InfraRed Imaging System (OSIRIS) instrument, the Swedish-designed Stratosphere Troposphere Exchange And climate Monitoring Radiometer (STEAMR) that is a follow-on instrument to the sub-millimetre radiometer (SMR) that currently operates with OSIRIS on Odin, and a Global Positioning System Radio Occultation instrument. The fourth instrument, also Canadian, is the Spatial Heterodyne Observations of Water (SHOW). SHOW will measure profiles of water vapour using its near-infrared absorption. Among other things, the ALISS package will deliver atmospheric composition (O3, H2O, NO2, HNO3, BrO, CO, aerosol, and others) measurements within the extremely important upper troposphere and lower stratosphere region for chemistry and climate studies. One application of interest would be using these measurements in conjunction with total column measurements from nadir-viewing instruments as well as data assimilation systems in order to better monitor and forecast air quality. Also, the heritage of these instruments implies the ALISS measurements will be extremely valuable in the continuation of climate-quality time series of important constituents such as stratospheric aerosols, water vapour, and ozone. Continuity of these vertically resolved data records is currently threatened by a looming gap in satellite-based limb sounders. This talk will outline the ALISS concept and the utility of the measurements.
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| 9. |
- Solheim, N., et al.
(författare)
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Randomized controlled trial of intra-articular ketorolac on pain and inflammation after minor arthroscopic knee surgery
- 2018
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Ingår i: Acta Anaesthesiologica Scandinavica. - : Wiley. - 0001-5172 .- 1399-6576. ; 62:6, s. 829-838
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Tidskriftsartikel (refereegranskat)abstract
- Background: Ketorolac is an effective non-steroidal anti-inflammatory drug, commonly used with local anaesthetics as part of local infiltration analgesia protocols following orthopaedic surgery. However, systemic uptake and drug action may be the major mechanism after local infiltration. The aims of this project were to study the effects of a small, systemically ineffective dose of ketorolac given intra-articularly for post-operative pain and also to study synovial inflammatory biomarkers. We investigated whether ketorolac affects pro-inflammatory biomarkers in an invitro model, as well.Methods: In this placebo-controlled, blind, randomized study, we analysed intra-articular ketorolac (5mg) in ambulatory minor knee surgery patients with moderate or severe pain (n=44). We assessed post-operative pain intensity (n=44) and analysed microdialysis samples taken from knee synovial tissue every 20min (n=34). We also tested cyclooxygenase-independent effects of ketorolac in synovial cells stimulated by prostaglandin E-2 and chondroitin sulphate invitro.Results: Intra-articular ketorolac (5mg) administration did not reduce pain or synovial pro-inflammatory cytokines CXCL1, IL-8, and MCP-1, 0-120min after knee arthroscopy. Female gender was a risk factor for moderate or severe pain (relative risk 1.45, 95% confidence interval 1.04-2.01). Paradoxically, ketorolac increased the release of CXCL1 and IL-8 in prostaglandin E-2 and chondroitin sulphate-stimulated synovial cells invitro.Conclusion: Ketorolac prescribed at a low dose intra-articularly does not produce any detectable analgesic effect after minor knee surgery.
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| 10. |
- Wendin, K, et al.
(författare)
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Low-fat mayonnaise: Influences of fat content, aroma compounds and thickeners
- 1997
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Ingår i: FOOD HYDROCOLLOIDS. - : OXFORD UNIV PRESS. - 0268-005X. ; 11:1, s. 87-99
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The effects of fat content and thickeners, propylene glycol alginate (PGA; 1.40%) and guar gum (1.55%), on sensory and instrumental quality descriptors on reduced fat mayonnaises (15 and 30% fat) with and without added aroma compounds, citral (semi-polar)
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