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Sökning: WFRF:(Linder Martin)

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1.
  • Bravo, L, et al. (författare)
  • 2021
  • swepub:Mat__t
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2.
  • Tabiri, S, et al. (författare)
  • 2021
  • swepub:Mat__t
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3.
  • Glasbey, JC, et al. (författare)
  • 2021
  • swepub:Mat__t
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4.
  • Khatri, C, et al. (författare)
  • Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study
  • 2021
  • Ingår i: BMJ open. - : BMJ. - 2044-6055. ; 11:11, s. e050830-
  • Tidskriftsartikel (refereegranskat)abstract
    • Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis.SettingProspective, international, multicentre, observational cohort study.ParticipantsPatients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative).Primary outcome30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality.ResultsThis study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p<0.001), age >80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787).ConclusionsPatients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups.Trial registration numberNCT04323644
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5.
  • 2021
  • swepub:Mat__t
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6.
  • 2021
  • swepub:Mat__t
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7.
  • Tinetti, Giovanna, et al. (författare)
  • The EChO science case
  • 2015
  • Ingår i: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 40:2-3, s. 329-391
  • Tidskriftsartikel (refereegranskat)abstract
    • The discovery of almost two thousand exoplanets has revealed an unexpectedly diverse planet population. We see gas giants in few-day orbits, whole multi-planet systems within the orbit of Mercury, and new populations of planets with masses between that of the Earth and Neptune-all unknown in the Solar System. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? How do planetary systems work and what causes the exceptional diversity observed as compared to the Solar System? The EChO (Exoplanet Characterisation Observatory) space mission was conceived to take up the challenge to explain this diversity in terms of formation, evolution, internal structure and planet and atmospheric composition. This requires in-depth spectroscopic knowledge of the atmospheres of a large and well-defined planet sample for which precise physical, chemical and dynamical information can be obtained. In order to fulfil this ambitious scientific program, EChO was designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large, diverse and well-defined planet sample within its 4-year mission lifetime. The transit and eclipse spectroscopy method, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allows us to measure atmospheric signals from the planet at levels of at least 10(-4) relative to the star. This can only be achieved in conjunction with a carefully designed stable payload and satellite platform. It is also necessary to provide broad instantaneous wavelength coverage to detect as many molecular species as possible, to probe the thermal structure of the planetary atmospheres and to correct for the contaminating effects of the stellar photosphere. This requires wavelength coverage of at least 0.55 to 11 mu m with a goal of covering from 0.4 to 16 mu m. Only modest spectral resolving power is needed, with R similar to 300 for wavelengths less than 5 mu m and R similar to 30 for wavelengths greater than this. The transit spectroscopy technique means that no spatial resolution is required. A telescope collecting area of about 1 m(2) is sufficiently large to achieve the necessary spectro-photometric precision: for the Phase A study a 1.13 m(2) telescope, diffraction limited at 3 mu m has been adopted. Placing the satellite at L2 provides a cold and stable thermal environment as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. EChO has been conceived to achieve a single goal: exoplanet spectroscopy. The spectral coverage and signal-to-noise to be achieved by EChO, thanks to its high stability and dedicated design, would be a game changer by allowing atmospheric composition to be measured with unparalleled exactness: at least a factor 10 more precise and a factor 10 to 1000 more accurate than current observations. This would enable the detection of molecular abundances three orders of magnitude lower than currently possible and a fourfold increase from the handful of molecules detected to date. Combining these data with estimates of planetary bulk compositions from accurate measurements of their radii and masses would allow degeneracies associated with planetary interior modelling to be broken, giving unique insight into the interior structure and elemental abundances of these alien worlds. EChO would allow scientists to study exoplanets both as a population and as individuals. The mission can target super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300-3000 K) of F to M-type host stars. The EChO core science would be delivered by a three-tier survey. The EChO Chemical Census: This is a broad survey of a few-hundred exoplanets, which allows us to explore the spectroscopic and chemical diversity of the exoplanet population as a whole. The EChO Origin: This is a deep survey of a subsample of tens of exoplanets for which significantly higher signal to noise and spectral resolution spectra can be obtained to explain the origin of the exoplanet diversity (such as formation mechanisms, chemical processes, atmospheric escape). The EChO Rosetta Stones: This is an ultra-high accuracy survey targeting a subsample of select exoplanets. These will be the bright "benchmark" cases for which a large number of measurements would be taken to explore temporal variations, and to obtain two and three dimensional spatial information on the atmospheric conditions through eclipse-mapping techniques. If EChO were launched today, the exoplanets currently observed are sufficient to provide a large and diverse sample. The Chemical Census survey would consist of > 160 exoplanets with a range of planetary sizes, temperatures, orbital parameters and stellar host properties. Additionally, over the next 10 years, several new ground- and space-based transit photometric surveys and missions will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO's launch and enable the atmospheric characterisation of hundreds of planets.
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8.
  • Meyer, H.F., et al. (författare)
  • Overview of physics studies on ASDEX Upgrade
  • 2019
  • Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
  • Forskningsöversikt (refereegranskat)abstract
    • The ASDEX Upgrade (AUG) programme, jointly run with the EUROfusion MST1 task force, continues to significantly enhance the physics base of ITER and DEMO. Here, the full tungsten wall is a key asset for extrapolating to future devices. The high overall heating power, flexible heating mix and comprehensive diagnostic set allows studies ranging from mimicking the scrape-off-layer and divertor conditions of ITER and DEMO at high density to fully non-inductive operation (q 95 = 5.5, ) at low density. Higher installed electron cyclotron resonance heating power 6 MW, new diagnostics and improved analysis techniques have further enhanced the capabilities of AUG. Stable high-density H-modes with MW m-1 with fully detached strike-points have been demonstrated. The ballooning instability close to the separatrix has been identified as a potential cause leading to the H-mode density limit and is also found to play an important role for the access to small edge-localized modes (ELMs). Density limit disruptions have been successfully avoided using a path-oriented approach to disruption handling and progress has been made in understanding the dissipation and avoidance of runaway electron beams. ELM suppression with resonant magnetic perturbations is now routinely achieved reaching transiently . This gives new insight into the field penetration physics, in particular with respect to plasma flows. Modelling agrees well with plasma response measurements and a helically localised ballooning structure observed prior to the ELM is evidence for the changed edge stability due to the magnetic perturbations. The impact of 3D perturbations on heat load patterns and fast-ion losses have been further elaborated. Progress has also been made in understanding the ELM cycle itself. Here, new fast measurements of and E r allow for inter ELM transport analysis confirming that E r is dominated by the diamagnetic term even for fast timescales. New analysis techniques allow detailed comparison of the ELM crash and are in good agreement with nonlinear MHD modelling. The observation of accelerated ions during the ELM crash can be seen as evidence for the reconnection during the ELM. As type-I ELMs (even mitigated) are likely not a viable operational regime in DEMO studies of 'natural' no ELM regimes have been extended. Stable I-modes up to have been characterised using -feedback. Core physics has been advanced by more detailed characterisation of the turbulence with new measurements such as the eddy tilt angle - measured for the first time - or the cross-phase angle of and fluctuations. These new data put strong constraints on gyro-kinetic turbulence modelling. In addition, carefully executed studies in different main species (H, D and He) and with different heating mixes highlight the importance of the collisional energy exchange for interpreting energy confinement. A new regime with a hollow profile now gives access to regimes mimicking aspects of burning plasma conditions and lead to nonlinear interactions of energetic particle modes despite the sub-Alfvénic beam energy. This will help to validate the fast-ion codes for predicting ITER and DEMO.
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9.
  • Stroth, U., et al. (författare)
  • Progress from ASDEX Upgrade experiments in preparing the physics basis of ITER operation and DEMO scenario development
  • 2022
  • Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 62:4
  • Tidskriftsartikel (refereegranskat)abstract
    • An overview of recent results obtained at the tokamak ASDEX Upgrade (AUG) is given. A work flow for predictive profile modelling of AUG discharges was established which is able to reproduce experimental H-mode plasma profiles based on engineering parameters only. In the plasma center, theoretical predictions on plasma current redistribution by a dynamo effect were confirmed experimentally. For core transport, the stabilizing effect of fast ion distributions on turbulent transport is shown to be important to explain the core isotope effect and improves the description of hollow low-Z impurity profiles. The L-H power threshold of hydrogen plasmas is not affected by small helium admixtures and it increases continuously from the deuterium to the hydrogen level when the hydrogen concentration is raised from 0 to 100%. One focus of recent campaigns was the search for a fusion relevant integrated plasma scenario without large edge localised modes (ELMs). Results from six different ELM-free confinement regimes are compared with respect to reactor relevance: ELM suppression by magnetic perturbation coils could be attributed to toroidally asymmetric turbulent fluctuations in the vicinity of the separatrix. Stable improved confinement mode plasma phases with a detached inner divertor were obtained using a feedback control of the plasma β. The enhanced D α H-mode regime was extended to higher heating power by feedback controlled radiative cooling with argon. The quasi-coherent exhaust regime was developed into an integrated scenario at high heating power and energy confinement, with a detached divertor and without large ELMs. Small ELMs close to the separatrix lead to peeling-ballooning stability and quasi continuous power exhaust. Helium beam density fluctuation measurements confirm that transport close to the separatrix is important to achieve the different ELM-free regimes. Based on separatrix plasma parameters and interchange-drift-Alfvén turbulence, an analytic model was derived that reproduces the experimentally found important operational boundaries of the density limit and between L- and H-mode confinement. Feedback control for the X-point radiator (XPR) position was established as an important element for divertor detachment control. Stable and detached ELM-free phases with H-mode confinement quality were obtained when the XPR was moved 10 cm above the X-point. Investigations of the plasma in the future flexible snow-flake divertor of AUG by means of first SOLPS-ITER simulations with drifts activated predict beneficial detachment properties and the activation of an additional strike point by the drifts.
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10.
  • Chen, Qiuyu, et al. (författare)
  • Satellite observations of gravity wave momentum flux in the mesosphere and lower thermosphere (MLT) : feasibility and requirements
  • 2022
  • Ingår i: Atmospheric Measurement Techniques. - : Copernicus GmbH. - 1867-1381 .- 1867-8548. ; 15:23, s. 7071-7103
  • Tidskriftsartikel (refereegranskat)abstract
    • In the recent decade it became evident that we need to revise our picture of how gravity waves (GWs) reach the mesosphere and lower thermosphere (MLT). This has consequences for our understanding not just of the properties of the GWs themselves, but in particular of the global circulation in the MLT. Information on spectral distribution, direction, and zonal mean GW momentum flux is required to test the theoretical and modeling findings. In this study, we propose a constellation of two CubeSats for observing mesoscale GWs in the MLT region by means of temperature limb sounding in order to derive such constraints. Each CubeSat deploys a highly miniaturized spatial heterodyne interferometer (SHI) for the measurement of global oxygen atmospheric band emissions. From these emissions, the 3-D temperature structure can be inferred. We propose obtaining four independent observation tracks by splitting the interferograms in the center and thus gaining two observation tracks for each satellite. We present a feasibility study of this concept based on self-consistent, high-resolution global model data. This yields a full chain of end-to-end (E2E) simulations incorporating (1) orbit simulation, (2) airglow forward modeling, (3) tomographic temperature retrieval, (4) 3-D wave analysis, and (5) GW momentum flux (GWMF) calculation. The simulation performance is evaluated by comparing the retrieved zonal mean GWMF with that computed directly from the model wind data. A major question to be considered in our assessment is the minimum number of tracks required for the derivation of 3-D GW parameters. The main result from our simulations is that the GW polarization relations are still valid in the MLT region and can thus be employed for inferring GWMF from the 3-D temperature distributions. Based on the E2E simulations for gaining zonal mean climatologies of GW momentum flux, we demonstrate that our approach is robust and stable, given a four-track observation geometry and the expected instrument noise under nominal operation conditions. Using phase speed and direction spectra we show also that the properties of individual wave events are recovered when employing four tracks. Finally, we discuss the potential of the proposed observations to address current topics in the GW research. We outline for which investigations ancillary data are required to answer science questions.
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11.
  • Heinze, Karolin, et al. (författare)
  • Validated biomarker assays confirm ARID1A loss is confounded with MMR deficiency, CD8 TIL infiltration, and provides no independent prognostic value in endometriosis-associated ovarian carcinomas.
  • 2021
  • Ingår i: The Journal of pathology. - : Wiley. - 1096-9896 .- 0022-3417. ; 256:4, s. 388-401
  • Tidskriftsartikel (refereegranskat)abstract
    • ARID1A (BAF250a) is a component of the SWI/SNF chromatin modifying complex, plays an important tumour suppressor role, and is considered prognostic in several malignancies. However, in ovarian carcinomas there are contradictory reports on its relationship to outcome, immune response, and correlation with clinicopathological features. We assembled a series of 1,623 endometriosis-associated ovarian carcinomas, including 1,078 endometrioid (ENOC) and 545 clear cell (CCOC) ovarian carcinomas through combining resources of the Ovarian Tumor Tissue Analysis (OTTA) Consortium, the Canadian Ovarian Unified Experimental Resource (COEUR), local, and collaborative networks. Validated immunohistochemical surrogate assays for ARID1A mutations were applied to all samples. We investigated associations between ARID1A loss/mutation, clinical features, outcome, CD8+ tumour-infiltrating lymphocytes (CD8+ TIL), and DNA mismatch repair deficiency (MMRd). ARID1A loss was observed in 42% of CCOC and 25% of ENOC. We found no associations between ARID1A loss and outcomes, stage, age, or CD8+ TIL status in CCOC. Similarly, we found no association with outcome or stage in endometrioid cases. In ENOC, ARID1A loss was more prevalent in younger patients (p=0.012), and associated with MMRd (p<0.001), and presence of CD8+ TIL (p=0.008). Consistent with MMRd being causative of ARID1A mutations, in a subset of ENOC we also observed an association between ARID1A loss-of-function mutation as a result of small indels (p=0.035, versus single nucleotide variants). In ENOC, the association between ARID1A loss, CD8+ TIL, and age, appears confounded by MMRd status. Although this observation does not explicitly rule out a role for ARID1A influence on CD8+ TIL infiltration in ENOC, given current knowledge regarding MMRd, it seems more likely that effects are dominated by the hypermutation phenotype. This large dataset with consistently applied biomarker assessment now provides a benchmark for the prevalence of ARID1A loss-of-function mutations in endometriosis-associated ovarian cancers and brings clarity to the prognostic significance. This article is protected by copyright. All rights reserved.
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13.
  • Stone, Vicki, et al. (författare)
  • The Essential Elements of a Risk Governance Framework for Current and Future Nanotechnologies
  • 2018
  • Ingår i: Risk Analysis. - : Wiley. - 0272-4332 .- 1539-6924. ; 38:7, s. 1321-1331
  • Tidskriftsartikel (refereegranskat)abstract
    • Societies worldwide are investing considerable resources into the safe development and use of nanomaterials. Although each of these protective efforts is crucial for governing the risks of nanomaterials, they are insufficient in isolation. What is missing is a more integrative governance approach that goes beyond legislation. Development of this approach must be evidence based and involve key stakeholders to ensure acceptance by end users. The challenge is to develop a framework that coordinates the variety of actors involved in nanotechnology and civil society to facilitate consideration of the complex issues that occur in this rapidly evolving research and development area. Here, we propose three sets of essential elements required to generate an effective risk governance framework for nanomaterials. (1) Advanced tools to facilitate risk-based decision making, including an assessment of the needs of users regarding risk assessment, mitigation, and transfer. (2) An integrated model of predicted human behavior and decision making concerning nanomaterial risks. (3) Legal and other (nano-specific and general) regulatory requirements to ensure compliance and to stimulate proactive approaches to safety. The implementation of such an approach should facilitate and motivate good practice for the various stakeholders to allow the safe and sustainable future development of nanotechnology.
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14.
  • Ade, Peter, et al. (författare)
  • The Simons Observatory : science goals and forecasts
  • 2019
  • Ingår i: Journal of Cosmology and Astroparticle Physics. - : IOP Publishing. - 1475-7516. ; :2
  • Tidskriftsartikel (refereegranskat)abstract
    • The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations in the early 2020s. We describe the scientific goals of the experiment, motivate the design, and forecast its performance. SO will measure the temperature and polarization anisotropy of the cosmic microwave background in six frequency bands centered at: 27, 39, 93, 145, 225 and 280 GHz. The initial con figuration of SO will have three small-aperture 0.5-m telescopes and one large-aperture 6-m telescope, with a total of 60,000 cryogenic bolometers. Our key science goals are to characterize the primordial perturbations, measure the number of relativistic species and the mass of neutrinos, test for deviations from a cosmological constant, improve our understanding of galaxy evolution, and constrain the duration of reionization. The small aperture telescopes will target the largest angular scales observable from Chile, mapping approximate to 10% of the sky to a white noise level of 2 mu K-arcmin in combined 93 and 145 GHz bands, to measure the primordial tensor-to-scalar ratio, r, at a target level of sigma(r) = 0.003. The large aperture telescope will map approximate to 40% of the sky at arcminute angular resolution to an expected white noise level of 6 mu K-arcmin in combined 93 and 145 GHz bands, overlapping with the majority of the Large Synoptic Survey Telescope sky region and partially with the Dark Energy Spectroscopic Instrument. With up to an order of magnitude lower polarization noise than maps from the Planck satellite, the high-resolution sky maps will constrain cosmological parameters derived from the damping tail, gravitational lensing of the microwave background, the primordial bispectrum, and the thermal and kinematic Sunyaev-Zel'dovich effects, and will aid in delensing the large-angle polarization signal to measure the tensor-to-scalar ratio. The survey will also provide a legacy catalog of 16,000 galaxy clusters and more than 20,000 extragalactic sources.
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15.
  • Aprile, E., et al. (författare)
  • Effective Field Theory and Inelastic Dark Matter Results from XENON1T
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • In this work we expand on the XENON1T nuclear recoil searches and study the individual signals of Dark Matter interactions from operators up to dimension-eight in a Chiral Effective Field Theory (ChEFT) as well as a model of inelastic Dark Matter using data from the two science runs of the detector totalling 1 tonne*year exposure. For these analyses we extended the region of interest from [4.9, 40.9]keVnr to [4.9, 54.4]keVnr to enhance our sensitivity for signals that peak at nonzero energies. We show that the data is consistent with a background only hypothesis, with small excesses in the models which peak between 20 and 50keVnr, obtaining a maximum local discovery significance of 1.7 for the VVs ChEFT model for a WIMP mass of 70GeV/c2, and 1.8 for an iDM particle of 50GeV/c2 with a mass splitting of 100keV/c2. For each model we report 90% confidence level upper limits. We also report limits on three benchmark models of WIMP interaction using ChEFT for which we investigate the effect of isospin breaking interactions, reporting up to 6 orders of magnitude weaker limits with respect to the isospin conserving case driven by cancellations in the expected rate.
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16.
  • Aprile, E., et al. (författare)
  • Emission of single and few electrons in XENON1T and limits on light dark matter
  • 2022
  • Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 106:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Delayed single- and few-electron emissions plague dual-phase time projection chambers, limiting their potential to search for light-mass dark matter. This paper examines the origins of these events in the XENON1T experiment. Characterization of the intensity of delayed electron backgrounds shows that the resulting emissions are correlated, in time and position, with high-energy events and can effectively be vetoed. In this work we extend previous S2-only analyses down to a single electron. From this analysis, after removing the correlated backgrounds, we observe rates <30 events/(electron×kg×day) in the region of interest spanning 1 to 5 electrons. We derive 90% confidence upper limits for dark matter-electron scattering, first direct limits on the electric dipole, magnetic dipole, and anapole interactions, and bosonic dark matter models, where we exclude new parameter space for dark photons and solar dark photons.
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17.
  • Bjurström, Martin F., et al. (författare)
  • Adherence to a restrictive red blood cell transfusion strategy in critically ill patients : An observational study
  • 2024
  • Ingår i: Acta Anaesthesiologica Scandinavica. - : John Wiley & Sons. - 0001-5172 .- 1399-6576.
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundRandomized controlled trials relatively consistently show that restrictive red blood cell (RBC) transfusion strategies are safe and associated with similar outcomes compared to liberal transfusion strategies in critically ill patients. Based on these data, the general threshold for RBC transfusion was changed to 70 g/L at a 9-bed tertiary level intensive care unit in September 2020. Implementation measures included lectures, webinars and feedback during clinical practice. The aim of this study was to investigate how implementation of a restrictive transfusion strategy influenced RBC usage, haemoglobin trigger levels and adherence to prescribed trigger levels.MethodsIn this registry-based, observational study, critically ill adult patients without massive bleeding were included and divided into a pre-cohort, with admissions prior to the change of transfusion strategy, and a post-cohort, with admissions following the change of transfusion strategy. These cohorts were compared regarding key RBC transfusion-related variables.ResultsIn total 5626 admissions were included in the analyses (pre-cohort n = 4373, post-cohort n = 1253). The median volume (interquartile range, IQR) of RBC transfusions per 100 admission days, in the pre-cohort was 6120 (4110–8110) mL versus 3010 (2890–4970) mL in the post-cohort (p < .001). This corresponds to an estimated median saving of 1128 € per 100 admission days after a restrictive RBC transfusion strategy was implemented. In total, 26% of the admissions in the pre-cohort and 19% in the post-cohort (p < .001) received RBC transfusion(s) during days 0–10. Both median (IQR) prescribed trigger levels (determined by intensivist) and actual haemoglobin trigger levels (i.e., levels prior to actual administration of transfusion) were higher in the pre- versus post-cohort (90 [80–100] vs. 80 [72–90] g/L, p < .001 and 89 [82–96] g/L vs. 83 [79–94], p < .001, respectively). Percentage of days without compliance with the prescribed transfusion trigger was higher in the pre-cohort than in the post-cohort (23% vs. 14%, p < .001). Sensitivity analyses, excluding patients with traumatic brain injury, ischemic heart disease and COVID-19 demonstrated similar results.ConclusionsImplementation of a restrictive transfusion trigger in a critical care setting resulted in lasting decreased RBC transfusion use and costs, decreased prescribed and actual haemoglobin trigger levels and improved adherence to prescribed haemoglobin trigger levels.
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19.
  • Dankiewicz, Josef, et al. (författare)
  • Heparin-binding protein: An early indicator of critical illness and predictor of outcome in cardiac arrest.
  • 2013
  • Ingår i: Resuscitation. - : Elsevier BV. - 1873-1570 .- 0300-9572. ; 84:7, s. 935-939
  • Tidskriftsartikel (refereegranskat)abstract
    • AIM: To investigate plasma levels of the neutrophil-borne heparin-binding protein (HBP) in patients with induced hypothermia after cardiac arrest (CA), and to study any association to severity of organ failure, incidence of infection and neurological outcome. METHODS: This study included 84 patients with CA of mixed origin who were treated with hypothermia. Plasma samples from 7 time points during the first 72h after return of spontaneous circulation (ROSC) were collected and analyzed for HBP with an ELISA. Outcomes were dichotomized: a cerebral performance category scale (CPC) of 1-2 at 6 months follow-up was considered a good outcome, a CPC of 3-5, a poor outcome. Patient data, including APACHE II and SOFA-scores were retrieved from the computerized system for quality assurance for intensive care. RESULTS: At 6h and 12h after CA, plasma levels of HBP were significantly higher among patients with a poor outcome. A receiver operated characteristics (ROC)-analysis yielded respective areas under curve (AUC) values of 0.68 and 0.70. This was similar to APACHE II and SOFA-score AUC values. There was a significant correlation between early elevated HBP-values and time to ROSC. HBP-levels were not higher in patients with infections at any time. CONCLUSIONS: Elevated HBP is an early indicator of organ failure and poor neurological outcome after CA, independent of microbial infection, and should be further evaluated in prospective trials. The temporal profile of HBP is suggestive of a role in the pathogenesis of critical illness after CA.
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20.
  • Elmlund, Hans, et al. (författare)
  • Cryo-EM Reveals Promoter DNA Binding and Conformational Flexibility of the General Transcription Factor TFIID
  • 2009
  • Ingår i: Structure. - : Elsevier BV. - 0969-2126 .- 1878-4186. ; 17:11, s. 1442-1452
  • Tidskriftsartikel (refereegranskat)abstract
    • The general transcription factor IID (TFIID) is required for initiation of RNA polymerase II-dependent transcription at many eukaryotic promoters. TFIID comprises the TATA-binding protein (TBP) and several conserved TBP-associated factors (TAFs). Recognition of the core promoter by TFIID assists assembly of the preinitiation complex. Using cryo-electron microscopy in combination with methods for ab initio single-particle reconstruction and heterogeneity analysis, we have produced density maps of two conformational states of Schizosaccharomyces pombe TFIID, containing and lacking TBP. We report that TBP-binding is coupled to a massive histone-fold domain rearrangement. Moreover, docking of the TBP-TAF1(N-terminus) atomic structure to the THID map and reconstruction of a TAF-promoter DNA complex helps to account for TAF-dependent regulation of promoter-TBP and promoter-TAF interactions.
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22.
  • Gimsing, Peter, et al. (författare)
  • Effect of pamidronate 30 mg versus 90 mg on physical function in patients with newly diagnosed multiple myeloma (Nordic Myeloma Study Group): a double-blind, randomised controlled trial
  • 2010
  • Ingår i: LANCET ONCOLOGY. - : Elsevier Science B.V., Amsterdam.. - 1470-2045 .- 1474-5488. ; 11:10, s. 973-982
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Compared with placebo, prophylactic treatment with bisphosphonates reduces risk of skeletal events in patients with multiple myeloma. However, because of toxicity associated with long-term bisphosphonate treatment, establishing the lowest effective dose is important. This study compared the effect of two doses of pamidronate on health-related quality of life and skeletal morbidity in patients with newly diagnosed multiple myeloma. Methods This double-blind, randomised, phase 3 trial was undertaken at 37 clinics in Denmark, Norway, and Sweden. Patients with multiple myeloma who were starting antimyeloma treatment were randomly assigned in a 1:1 ratio to receive one of two doses of pamidronate (30 mg or 90 mg) given by intravenous infusion once a month for at least 3 years. Randomisation was done by use of a central, computerised minimisation system. Primary outcome was physical function after 12 months estimated by the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire (scale 0-100). All patients who returned questionnaires at 12 months and were still on study treatment were included in the analysis of the primary endpoint. This study is registered with ClinicalTrials. gov, number NCT00376883. Findings From January, 2001, until August, 2005, 504 patients were randomly assigned to pamidronate 30 mg or 90 mg (252 in each group). 157 patients in the 90 mg group and 156 in the 30 mg group were included in the primary analysis. Mean physical function at 12 months was 66 points (95% CI 62.9-70.0) in the 90 mg group and 68 points (64.6-71.4) in the 30 mg group (95% CI of difference -6.6 to 3.3; p=0.52). Median time to first skeletal-related event in patients who had such an event was 9.2 months (8.1-10.7) in the 90 mg group and 10-2 months (7.3-14.0) in the 30 mg group (p=0.63). In a retrospective analysis, eight patients in the pamidronate 90 mg group developed osteonecrosis of the jaw compared with two patients in the 30 mg group. Interpretation Monthly infusion of pamidronate 30 mg should be the recommended dose for prevention of bone disease in patients with multiple myeloma.
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23.
  • Günther, Mattias, et al. (författare)
  • Incidence, demographics, and outcomes of penetrating trauma in Sweden during the past decade
  • 2021
  • Ingår i: Frontiers in Neurology. - : Frontiers. - 1664-2295. ; 12
  • Tidskriftsartikel (refereegranskat)abstract
    • Trauma injury is the sixth leading cause of death worldwide, and interpersonal violence is one of the major contributors in particular regarding injuries to the head and neck. The incidence, demographics, and outcomes of penetrating trauma reaching hospitals in Sweden are not known. We report the largest, nationwide epidemiological study of penetrating injuries in Sweden, using the Swedish Trauma Registry (SweTrau). A multi-center retrospective descriptive study of 4,776 patients was conducted with penetrating injuries in Sweden, between 2012 and 2018. Due to the increase in coverage of the SweTrau registry during the same period, we chose to analyze the average number of cases for the time intervals 2013–2015 and 2016–2018 and compare those trends to the reports of the Swedish National Council for Crime Prevention (Brå) as well. A total of 663 patients had Injury Severity Score (ISS) ≥ 15 at admission and were included in the study. Three hundred and sixty-eight (55.5%) were stab wounds (SW), 245 (37.0%) gunshot wounds (GSW), and 50 (7.5%) other traumas. A majority of the cases involved injuries to the head, neck, and face. SW increased from 145 during 2013–2015 to 184 during the second period of 2016–2018. The increase was greater for GSW from 92 to 141 during the same respective periods. This trend of increase over time was also seen in head, neck, and face injuries. The 30-day mortality was unaffected (48–47%) in GSW and trended toward lower in SW (24–21%) when comparing 2013–2015 with 2016–2018. Patients with head trauma had 45% mortality compared to 18% for non-head trauma patients. Head trauma also resulted in worse outcomes, only 13% had Glasgow outcome score (GOS) 5 compared to 27% in non-head trauma. The increasing number of cases of both SW and GSW corresponded well with reports from Brå although further studies also are needed to address deaths outside of hospitals and not registered at the SweTrau. The majority of cases had injuries to the head, neck, and face and were associated with higher mortality and poor outcomes. Further studies are needed to understand the contributing factors to these worse outcomes in Sweden and whether more targeted trauma care of these patients can improve outcomes.
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24.
  • Heyn, Hans-Martin, 1987, et al. (författare)
  • Requirement Engineering Challenges for AI-intense Systems Development
  • 2021
  • Ingår i: ICSE '21: Proceedings of the 1st Workshop on AI Engineering – Software Engineering for AI.
  • Konferensbidrag (refereegranskat)abstract
    • Availability of powerful computation and communication technology as well as advances in artificial intelligence enable a new generation of complex, AI-intense systems and applications. Such systems and applications promise exciting improvements on a societal level, yet they also bring with them new challenges for their development. In this paper we argue that significant challenges relate to defining and ensuring behaviour and quality attributes of such systems and applications. We specifically derive four challenge areas from relevant use cases of complex, AI-intense systems and applications related to industry, transportation, and home automation: understanding, determining, and specifying (i) contextual definitions and requirements,(ii) data attributes and requirements, (iii) performance definition and monitoring, and (iv) the impact of human factors on system acceptance and success. Solving these challenges will imply process support that integrates new requirements engineering methods into development approaches for complex, AI-intense systems and applications. We present these challenges in detail and propose a research roadmap.
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25.
  • Heyn, Hans-Martin, 1987, et al. (författare)
  • Setting AI in Context: A Case Study on Defining the Context and Operational Design Domain for Automated Driving
  • 2022
  • Ingår i: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. ; 13216 LNCS, s. 199-215
  • Konferensbidrag (refereegranskat)abstract
    • [Context and motivation] For automated driving systems, the operational context needs to be known in order to state guarantees on performance and safety. The operational design domain (ODD) is an abstraction of the operational context, and its definition is an integral part of the system development process. [Question/problem] There are still major uncertainties in how to clearly define and document the operational context in a diverse and distributed development environment such as the automotive industry. This case study investigates the challenges with context definitions for the development of perception functions that use machine learning for automated driving. [Principal ideas/results] Based on qualitative analysis of data from semi-structured interviews, the case study shows that there is a lack of standardisation for context definitions across the industry, ambiguities in the processes that lead to deriving the ODD, missing documentation of assumptions about the operational context, and a lack of involvement of function developers in the context definition. [Contribution] The results outline challenges experienced by an automotive supplier company when defining the operational context for systems using machine learning. Furthermore, the study collected ideas for potential solutions from the perspective of practitioners.
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26.
  • Hjorth, Martin, et al. (författare)
  • Thalidomide and dexamethasone vs. bortezomib and dexamethasone for melphalan refractory myeloma: a randomized study.
  • 2012
  • Ingår i: European journal of haematology. - : Wiley. - 0902-4441 .- 1600-0609. ; 88:6, s. 485-496
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
    • Objectives: Thalidomide and bortezomib have been frequently used for second-line therapy in patients with myeloma relapsing after or refractory to initial melphalan-based treatment, but no randomized trials have been published comparing these two treatment alternatives. Methods: Thalidomide- and bortezomib-naïve patients with melphalan refractory myeloma were randomly assigned to low-dose thalidomide + dexamethasone (Thal-Dex) or bortezomib + dexamethasone (Bort-Dex). At progression on either therapy, the patients were offered crossover to the alternative drug combination. An estimated 300 patients would be needed for the trial to detect a 50% difference in median PFS between the treatment arms. Results: After inclusion of 131 patients, the trial was prematurely closed because of low accrual. Sixty-seven patients were randomized to Thal-Dex and 64 to Bort-Dex. Progression-free survival was similar (median, 9.0 months for Thal-Dex and 7.2 for Bort-Dex). Response rate was similar (55% for Thal-Dex and 63% for Bort-Dex), but time to response was shorter (P < 0.05) and the VGPR rate higher (P < 0.01) for Bort-Dex. Time-to-other treatment after crossover was similar (median, 13.2 months for Thal-Dex and 11.2 months for Bort-Dex), as was overall survival (22.8 months for Thal-Dex and 19.0 for Bort-Dex). Venous thromboembolism was seen in seven patients and cerebrovascular events in four patients in the Thal-Dex group. Severe neuropathy, reactivation of herpes virus infections, and mental depression were more frequently observed in the Bort-Dex group. In the quality-of-life analysis, no difference was noted for physical function, pain, and global quality of life. Fatigue and sleep disturbances were significantly more prevalent in the Bort-Dex group. Conclusions: Thalidomide (50–100 mg daily) in combination with dexamethasone seems to have an efficacy comparable with that of bortezomib and dexamethasone in melphalan refractory myeloma. However, the statistical strength of the results in this study is limited by the low number of included patients.
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27.
  • Ho, Du, et al. (författare)
  • Mass estimation of a quadcopter using IMU data
  • 2017
  • Ingår i: 2017 International Conference on Unmanned Aircraft Systems (ICUAS), June 13-16, 2017, Miami, FL, USA. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781509044955 - 9781509044962 ; , s. 1260-1266
  • Konferensbidrag (refereegranskat)abstract
    • In this paper, an approach to estimate the mass of a quadcopter using only inertial measurements and pilot commands is presented. For this purpose, a lateral dynamic model describing the relation between the roll rate and the lateral acceleration is formulated. Due to the quadcopter’s inherent instability, a controller is used to stabilize the system and the data is collected in closed loop. Under the effect of feedback and disturbances, the inertial measurements used as input and output are correlated with the disturbances, which complicates the parameter estimation. The parameters of the model are estimated using several methods. The simulation and experimental results show that the instrumental-variable method has the best potential to estimate the mass of the quadcopter in this setup.
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28.
  • Ho, Du, et al. (författare)
  • Vertical modeling of a quadcopter for mass estimation and diagnosis purposes
  • 2017
  • Ingår i: Proceedings of the Workshop on Research, Education and Development on Unmanned Aerial Systems, RED-UAS, Linköping, Sweden, 3-5 October, 2017. - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538609392 - 9781538609408
  • Konferensbidrag (refereegranskat)abstract
    • In this work, we estimate a model of the vertical dynamics of a quadcopter and explain how this model can be used for mass estimation and diagnosis of system changes. First, a standard thrust model describing the relation between the calculated control signals of the rotors and the thrust that is commonly used in literature is estimated. The estimation results are compared to those using a refined thrust model and it turns out that the refined model gives a significant improvement. The combination of a nonlinear model and closed-loop data poses some challenges and it is shown that an instrumental variables approach can be used to obtain accurate estimates. Furthermore, we show that the refined model opens up for fault detection of the quadcopter. More specifically, this model can be used for mass estimation and also for diagnosis of other parameters that might vary between and during missions.
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29.
  • Holmström, Oscar, et al. (författare)
  • Point-of-Care Digital Cytology With Artificial Intelligence for Cervical Cancer Screening in a Resource-Limited Setting
  • 2021
  • Ingår i: JAMA Network Open. - : American Medical Association (AMA). - 2574-3805. ; 4:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Importance: Cervical cancer is highly preventable but remains a common and deadly cancer in areas without screening programs. The creation of a diagnostic system to digitize Papanicolaou test samples and analyze them using a cloud-based deep learning system (DLS) may provide needed cervical cancer screening to resource-limited areas.Objective: To determine whether artificial intelligence-supported digital microscopy diagnostics can be implemented in a resource-limited setting and used for analysis of Papanicolaou tests.Design, Setting, and Participants: In this diagnostic study, cervical smears from 740 HIV-positive women aged between 18 and 64 years were collected between September 1, 2018, and September 30, 2019. The smears were digitized with a portable slide scanner, uploaded to a cloud server using mobile networks, and used to train and validate a DLS for the detection of atypical cervical cells. This single-center study was conducted at a local health care center in rural Kenya.Exposures: Detection of squamous cell atypia in the digital samples by analysis with the DLS.Main Outcomes and Measures: The accuracy of the DLS in the detection of low- and high-grade squamous intraepithelial lesions in Papanicolaou test whole-slide images.Results: Papanicolaou test results from 740 HIV-positive women (mean [SD] age, 41.8 [10.3] years) were collected. The DLS was trained using 350 whole-slide images and validated on 361 whole-slide images (average size, 100 387 x 47 560 pixels). For detection of cervical cellular atypia, sensitivities were 95.7% (95% CI, 85.5%-99.5%) and 100% (95% CI, 82.4%-100%), and specificities were 84.7% (95% CI, 80.2%-88.5%) and 78.4% (95% CI, 73.6%-82.4%), compared with the pathologist assessment of digital and physical slides, respectively. Areas under the receiver operating characteristic curve were 0.94 and 0.96, respectively. Negative predictive values were high (99%-100%), and accuracy was high, particularly for the detection of high-grade lesions. Interrater agreement was substantial compared with the pathologist assessment of digital slides (kappa = 0.72) and fair compared with the assessment of glass slides (kappa = 0.36). No samples that were classified as high grade by manual sample analysis had false-negative assessments by the DLS.Conclusions and Relevance: In this study, digital microscopy with artificial intelligence was implemented at a rural clinic and used to detect atypical cervical smears with a high sensitivity compared with visual sample analysis.
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30.
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31.
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32.
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33.
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34.
  • Jeremiasen, Martin, et al. (författare)
  • Improvements in esophageal and gastric cancer care in Sweden-population-based results 2007-2016 from a national quality register
  • 2020
  • Ingår i: Diseases of the esophagus. - : Oxford University Press (OUP). - 1120-8694 .- 1442-2050. ; 33:3
  • Tidskriftsartikel (refereegranskat)abstract
    • The Swedish National Register for Esophageal and Gastric cancer was launched in 2006 and contains data with adequate national coverage and of high internal validity on patients diagnosed with these tumors. The aim of this study was to describe the evolution of esophageal and gastric cancer care as reflected in a population-based clinical registry. The study population was 12,242 patients (6,926 with esophageal and gastroesophageal junction (GEJ) cancers and 5,316 with gastric cancers) diagnosed between 2007 and 2016. Treatment strategies, short- and long-term mortality, gender aspects, and centralization were investigated. Neoadjuvant oncological treatment became increasingly prevalent during the study period. Resection rates for both esophageal/GEJ and gastric cancers decreased from 29.4% to 26.0% (P=0.022) and from 38.8% to 33.3% (P=0.002), respectively. A marked reduction in the number of hospitals performing esophageal and gastric cancer surgery was noted. In gastric cancer patients, an improvement in 30-day mortality from 4.2% to 1.6% (P=0.005) was evident. Overall 5-year survival after esophageal resection was 38.9%, being higher among women compared to men (47.5 vs. 36.6%; P<0.001), whereas no gender difference was seen in gastric cancer. During the recent decade, the analyses based on the Swedish National Register for Esophageal and Gastric cancer database demonstrated significant improvements in several important quality indicators of care for patients with esophagogastric cancers. The Swedish National Register for Esophageal and Gastric cancer offers an instrument not only for the control and endorsement of quality of care but also a unique tool for population-based clinical research.
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35.
  • Karsten, Agneta Linder-Aronson, et al. (författare)
  • The resistance to axial dislodgement of nickel titanium compression arch wire hooks - an in vitro study
  • 2019
  • Ingår i: Australasian Orthodontic Journal. - : Australian Society of Orthodontists. - 2207-7472. ; 35:1, s. 21-26
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: To evaluate the level of force required to axially dislodge nickel titanium compression hooks (Trillium Compression Hook (TM), Hespeler Orthodontics) placed on orthodontic arch wires in vitro. Materials and methods: Nickel titanium compression hooks were placed on arch wires with a specially designed pair of pliers. The resistance to axial dislodgement was tested on a total of 260 hooks placed in a standardised way on round (0.016 '', 0.018 '', 0.020 ''), square (0.020 x 0.020 '') and rectangular (0.016 x 0.022 '', 0.019 x 0.025 '', 0.021 x 0.025 '') stainless steel (Rocky Mountain Orthodontics), nickel titanium, or beta-titanium (Hespeler Orthodontics) arch wires. The forces required to displace the hooks were recorded using an Instron tensile testing machine. The data were compared with the results reported in similar studies on stainless steel crimpable arch wire hooks. Results: The forces required to dislodge the compression hooks varied between 45.0 N and 161.9 N. The hook's resistance to dislodgement was found to be high in all tested hook/wire combinations. The lowest recorded average dislodging force was found in the 0.020 '' nickel titanium group and the highest average force was in the 0.016 x 0.022 '' beta-titanium group. Conclusion: The forces needed to dislodge the tested nickel titanium compression arch wire hooks exceed the force levels previously reported for stainless steel crimpable arch wire hooks.
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36.
  • Krivosheeva, Olga, et al. (författare)
  • Kinetic and Equilibrium Aspects of Adsorption and Desorption of Class II Hydrophobins HFBI and HFBII at Silicon Oxynitride/Water and Air/Water Interfaces
  • 2013
  • Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 29:8, s. 2683-2691
  • Tidskriftsartikel (refereegranskat)abstract
    • Hydrophobins are relatively small globular proteins produced by filamentous fungi. They display unusual high surface activity and are implied as mediators of attachment to surfaces, which has resulted in high scientific and technological interest. In this work we focus on kinetic and equilibrium aspects of adsorption and desorption properties of two representatives of class II hydrophobins, namely HFBI and HFBII, at a negatively charged hydrophilic solid/water interface and at the air/water interface. The layers formed at the air/liquid interface were examined in a Langmuir trough, whereas layers formed at the solid/liquid interface were studied using dual polarization interferometry (DPI) under different flow conditions. For comparison, another globular protein, lysozyme, was also investigated. It was found that both the adsorbed amount and the adsorption kinetics were different for HFBI and HFBII, and the adsorption behavior of both hydrophobins on the negatively charged surface displayed some unusual features. For instance, even though the adsorption rate for HFBI was slowed down with increasing adsorbed amount as expected from packing constraints at the interface, the adsorption kinetics curves for HFBII displayed a region indicating adsorption cooperativity. Further, it was found that hydrophobin layers formed under flow partly desorbed when the flow was stopped, and the desorption rate for HFBII was enhanced in the presence of hydrophobins in solution.
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37.
  • Kullman, Eric, et al. (författare)
  • Covered versus uncovered self-expandable nitinol stents in the palliative treatment of malignant distal biliary obstruction: results from a randomized, multicenter study
  • 2010
  • Ingår i: GASTROINTESTINAL ENDOSCOPY. - : Elsevier Science B. V., Amsterdam. - 0016-5107 .- 1097-6779. ; 72:5, s. 915-923
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Covered biliary metal stents have been developed to prevent tumor ingrowth. Previous comparative studies are limited and often include few patients. Objective: To compare differences in stent patency, patient survival, and complication rates between covered and uncovered nitinol stents in patients with malignant biliary obstruction. Design: Randomized, multicenter trial conducted between January 2006 and October 2008. Setting: Ten sites serving a total catchment area of approximately 2.8 million inhabitants. Patients: A total of 400 patients with unresectable distal malignant biliary obstruction. Interventions: ERCP with insertion of covered or uncovered metal stent. Follow-up conducted monthly for symptoms indicating stent obstruction. Main Outcome Measurements: Time to stent failure, survival time, and complication rate. Results: The patient survival times were 116 days (interquartile range 242 days) and 174 days (interquartile range 284 days) in the covered and uncovered stent groups, respectively (P = .320). The first quartile stent patency time was 154 days in the covered stent group and 199 days in the uncovered stent group (P = .326). There was no difference in the incidence of pancreatitis or cholecystitis between the 2 groups. Stent migration occurred in 6 patients (3%) in the covered group and in no patients in the uncovered group (P = .030). Limitations: Randomization was not blinded. Conclusions: There were no significant differences in stent patency time, patient survival time, or complication rates between covered and uncovered nitinol metal stents in the palliative treatment of malignant distal biliary obstruction. However, covered stents migrated significantly more often compared with uncovered stents, and tumor ingrowth was more frequent in uncovered stents.
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38.
  • Lackner, Christian, et al. (författare)
  • Tram to Pedestrian Collisions—Priorities and Potentials
  • 2022
  • Ingår i: Frontiers in Future Transportation. - : Frontiers Media SA. - 2673-5210. ; 3
  • Tidskriftsartikel (refereegranskat)abstract
    • To improve mobility in cities in line with environmental goals, in urban traffic, trams represent an increasingly important means of transport. Due to the close interaction with other road users, this makes collisions with trams fairly frequent. This study has investigated accidents between trams and vulnerable road users resulting in personal injury, aimed at identifying priorities for simulating collisions between trams and pedestrians to assess passive safety measures. Tram accident data collection established throughout Europe from multiple sources and with varying degree of details, have been combined and analysed. These analyses comprise risk assessments per km-driven and general tram accident partner and site type evaluations, with more detailed analyses on accident site distance to the closest tram stop and injured body regions, respectively. In total, 7,535 tram-pedestrian accident resulting in 8,802 pedestrian injuries, collected in the year 2000–2021, was analysed. Accident risk ranges from 0.934 accidents per number of tram (million) km-driven, for slight injuries to 0.063 for fatal injuries. Pedestrians represent a large proportion of tram accident collision partners, especially for severe and fatal accidents. In accidents between trams and pedestrians, 3% of reported injuries are fatal, 23% severe and 74% minor. Generally, low-speed accidents close to tram stops often leading to minor injuries were observed to be of significant importance (<20m to the GPS location of a stop). Analysis of accidents was done bases on gender of the pedestrian showing overall similar involvements in accident with slight difference for various age groups and sites. Regardless of injury severity, the most frequently injured body region in accidents involving a tram is the head. Likewise, injuries sustained to the thorax, especially for higher injury severities are of high relevance, followed by injuries to the lower extremities. Based on this study, recommendations for developing reasonable tram-pedestrian accident scenarios for virtual testing can be derived for further optimisation of pedestrian safety of trams.
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39.
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40.
  • Lenhoff, Stig, et al. (författare)
  • Intensive therapy for multiple myeloma in patients younger than 60 years. Long-term results focusing on the effect of the degree of response on survival and relapse pattern after transplantation
  • 2006
  • Ingår i: Haematologica. - 0390-6078 .- 1592-8721. ; 91:9, s. 1228-1233
  • Tidskriftsartikel (refereegranskat)abstract
    • Background and Objectives. From 1994 to 1997 we conducted a population-based, prospective study on intensive therapy in newly diagnosed symptomatic myeloma patients younger than 60 years, comparing their survival to that of a conventionally treated historic population. Long-term results are presented, including the impact of the degree of response on survival and relapse pattern after transplantation. Design and Methods. The prospective population was formed of 397 patients and the historic population of 313 patients. Both populations were calculated to comprise more than 75% of the expected number of new cases. Results. After a median follow-up of 7 years survival was longer in the prospective population than in the historic one (median 60 versus 39 months; p=0.0002). When comparing only patients eligible for intensive therapy the median survival was 63 versus 44 months (p < 0.0001). Attaining a complete response was associated with prolonged event-free survival but not overall survival. The pattern of relapse after transplantation was heterogeneous but could be divided into four major groups; insidious, classical, plasmacytoma form and transformed disease. The median survival after relapse was 29 months. The relapse pattern and time to relapse predicted outcome. Patients relapsing with an insidious or classical form of disease with skeletal events only, or after a long lasting first response were likely to respond well to conventional salvage therapy. In contrast, relapse with multiple symptoms, transformed disease or a short duration of first response implied bad prognosis. Interpretation and conclusions. The relapse pattern after autologous transplantation is heterogeneous and response to salvage therapy is variable. The degree of response and event-free survival after transplantation are not reliable surrogate markers for survival.
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41.
  • Leo, Christoph, et al. (författare)
  • Holistic pedestrian safety assessment for average males and females
  • 2023
  • Ingår i: Frontiers in Public Health. - : Frontiers Media S.A.. - 2296-2565. ; 11
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: An integrated assessment framework that enables holistic safety evaluations addressing vulnerable road users (VRU) is introduced and applied in the current study. The developed method enables consideration of both active and passive safety measures and distributions of real-world crash scenario parameters. Methods: The likelihood of a specific virtual testing scenario occurring in real life has been derived from accident databases scaled to European level. Based on pre-crash simulations, it is determined how likely it is that scenarios could be avoided by a specific Autonomous Emergency Braking (AEB) system. For the unavoidable cases, probabilities for specific collision scenarios are determined, and the injury risk for these is determined, subsequently, from in-crash simulations with the VIVA+ Human Body Models combined with the created metamodel for an average male and female model. The integrated assessment framework was applied for the holistic assessment of car-related pedestrian protection using a generic car model to assess the safety benefits of a generic AEB system combined with current passive safety structures. Results: In total, 61,914 virtual testing scenarios have been derived from the different car-pedestrian cases based on real-world crash scenario parameters. Considering the occurrence probability of the virtual testing scenarios, by implementing an AEB, a total crash risk reduction of 81.70% was achieved based on pre-crash simulations. It was shown that 50 in-crash simulations per load case are sufficient to create a metamodel for injury prediction. For the in-crash simulations with the generic vehicle, it was also shown that the injury risk can be reduced by implementing an AEB, as compared to the baseline scenarios. Moreover, as seen in the unavoidable cases, the injury risk for the average male and female is the same for brain injuries and femoral shaft fractures. The average male has a higher risk of skull fractures and fractures of more than three ribs compared to the average female. The average female has a higher risk of proximal femoral fractures than the average male. Conclusions: A novel methodology was developed which allows for movement away from the exclusive use of standard-load case assessments, thus helping to bridge the gap between active and passive safety evaluations.
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42.
  • Lindén, Anja, et al. (författare)
  • Protocolised reduction of non-resuscitation fluids versus usual care in patients with septic shock (REDUSE): a protocol for a multicentre feasibility trial
  • 2023
  • Ingår i: Bmj Open. - : BMJ. - 2044-6055. ; 13:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Introduction Administration of large volumes of fluids is associated with poor outcome in septic shock. Recent data suggest that non-resuscitation fluids are the major source of fluids in the intensive care unit (ICU) patients suffering from septic shock. The present trial is designed to test the hypothesis that a protocol targeting this source of fluids can reduce fluid administration compared with usual care.Methods and analysis The design will be a multicentre, randomised, feasibility trial. Adult patients admitted to ICUs with septic shock will be randomised within 12 hours of admission to receive non-resuscitation fluids either according to a restrictive protocol or to receive usual care. The healthcare providers involved in the care of participants will not be blinded. The participants, outcome assessors at the 6-month follow-up and statisticians will be blinded. Primary outcome will be litres of fluids administered within 3 days of randomisation. Secondary outcomes will be proportion of randomised participants with outcome data on all-cause mortality; days alive and free of mechanical ventilation within 90 days of inclusion; any acute kidney injury and ischaemic events in the ICU (cerebral, cardiac, intestinal or limb ischaemia); proportion of surviving randomised patients who were assessed by European Quality of Life 5-Dimensions 5-Level questionnaire and Montreal Cognitive Assessment; proportion of all eligible patients who were randomised and proportion of participants experiencing at least one protocol violation.Ethics and dissemination Ethics approval has been obtained in Sweden. Results of the primary and secondary outcomes will be submitted for publication in a peer-reviewed journal.
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43.
  • Linder, Anna, et al. (författare)
  • Grading Bias and Young Adult Mental Health
  • 2022
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Various grading reforms and trends of more lenient grading have contributed to grade inflation in Sweden and other countries. Previous research shows that over-grading increases higher education enrolment, achievements and earnings, but no study has yet addressed the potential impact of grading bias on health. In this paper, we hypothesize that over-grading has a protective impact on mental health, either through a direct effect of performance feedback, or through mechanisms such as self-efficacy and university admission distortions. We test this hypothesis using Swedish individual-level register data for individuals graduating from upper secondary school in the years 2001-2004. Grading bias, which we interpret as over-grading, is constructed as the residual of final upper secondary school grades having controlled for results in a standardised test, itself not subject to grading leniency. Over-grading is further isolated by considering only within-school variation in over-grading and controlling for prior grades and school production. We show that over-grading has substantial significant protective impacts on the mental health of young adults, but only among female students. That grades themselves, independent of knowledge, substantially impact the production of health highlights an important health production mechanism, and also implies that any changes to the design of grading systems must consider these wider health implications.
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44.
  • Linder, Anna, et al. (författare)
  • Grading bias and young adult mental health
  • 2023
  • Ingår i: Health Economics. - : Wiley. - 1099-1050 .- 1057-9230. ; 32:3, s. 675-696
  • Tidskriftsartikel (refereegranskat)abstract
    • We study exposure to grading bias and provide novel evidence of its impact on mental health. Grading bias, which we interpret as over-grading, is constructed as the residual of final upper secondary school grades having controlled for results in a standardized test, itself not subject to grading leniency. Grading bias is further isolated by considering only within-school variation in over-grading and controlling for prior grades and school production. Using Swedish individual-level register data for individuals graduating from upper secondary school in the years 2001-2004, we show that over-grading has substantial significant protective impacts on the mental health of young adults, but only among female students. That grades themselves, independent of knowledge, substantially impact the production of health highlights an important health production mechanism, and implies that any changes to the design of grading systems must consider these wider health implications.
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45.
  • Linder, David, et al. (författare)
  • An energy release rate approach to cemented carbide fracture toughness for computational materials design
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • Integrated computational materials engineering and computational materials design have the potential to greatly accelerate materials development at reduced cost compared to conventional experimentally-based methods. These methodologies, however, require physically-based property models to be truly predictive. Fracture toughness is a critical material property of cemented carbides for high-performance mining and metal cutting tools. In the present work, a fracture toughness model framework based on the energy release rate formalism is presented and applied to conventional and alternative-binder cemented carbides. The framework is physically-based and designed to be modular, where each sub-model can be independently modified or replaced without disturbing the calculation-flow of the overall framework. In the presented examples, the sub-models are based on e.g. finite element simulations and atomistic calculations as well as limited calibration to experimental data. The model framework is intended for integration with previously developed computational tools and models, such as a composite hardness model and a grain growth model, for computational design of novel and improved cemented carbides with the aim to potentially substitute cobalt as the dominating binder phase in cemented carbides.
  •  
46.
  • Linder, David, et al. (författare)
  • Indentation behavior of highly confined elasto-plastic materials
  • Tidskriftsartikel (refereegranskat)abstract
    • The effect of geometric confinement is well-known from hardness measurements of thin films on stiff substrates and has been modeled both phenomenologically and using e.g. Finite Element Analysis. However, these models are mainly focused on a specific experiment or a certain material family. In the present work, Finite Element Analysis is used to gain a better understanding of the interplay between geometric constraints in various microstructures and a wide range of materials properties. It is shown that a very simple model can be used to replicate thin film hardness data where the film is softer than the substrate as well as how materials properties alter the indentation behavior of materials confined in one to three dimensions. It is shown that qualitative agreement with nanoindentation of the metallic binder phase in the complex 3D-microstructure of a cemented carbide is achieved using an axisymmetric “pill-box” model with classical plasticity. It is also shown that the effect of higher-order confinement can be described by the Korsunsky thin film hardness model by re-optimizing the fitting parameters. 
  •  
47.
  • Linder, David, et al. (författare)
  • Indentation behavior of highly confined elasto-plastic materials
  • 2020
  • Ingår i: International Journal of Solids and Structures. - : Elsevier. - 0020-7683 .- 1879-2146. ; 193-194, s. 69-78
  • Tidskriftsartikel (refereegranskat)abstract
    • The effect of geometric confinement is well-known from hardness measurements of thin films on stiff substrates and has been modeled both phenomenologically and using e.g. Finite Element Analysis. However, these models are mainly focused on a specific experiment or a certain material family. In the present work, Finite Element Analysis is used to gain a better understanding of the interplay between geometric constraints in various microstructures and a wide range of materials properties. It is shown that a very simple model can be used to replicate thin film hardness data where the film is softer than the substrate as well as how materials properties alter the indentation behavior of materials confined in one to three dimensions. It is shown that qualitative agreement with nanoindentation of the metallic binder phase in the complex 3D-microstructure of a cemented carbide is achieved using an axisymmetric “pill-box” model with classical plasticity. It is also shown that the effect of higher-order confinement can be described by the Korsunsky thin film hardness model by re-optimizing the fitting parameters.
  •  
48.
  • Linder, David, et al. (författare)
  • Martensite transformation in cemented carbides with alternative binders
  • 2016
  • Ingår i: World PM 2016 Congress and Exhibition. - : European Powder Metallurgy Association (EPMA). - 9781899072484
  • Konferensbidrag (refereegranskat)abstract
    • The recent interest in substitution of cobalt in cemented carbides has led to renewed efforts into finding alternative binders. Promising candidates are Fe and Ni-based systems which generally can be divided into austenitic (fcc) and martensitic (bct) binders. The martensitic transformation may drastically change the properties, thus, when designing an alternative binder it is important to know at what temperature and composition the martensitic transformation takes place. Furthermore, it is of interest to understand how the transformation is affected by the binder mean free path and the stresses in the binder introduced by the carbide grains. Another aspect, that is important for high temperature properties, is the tempering of martensite as well as reversion to austenite. The effect of these processes is here investigated along with how they influence the behavior of the cemented carbides at different temperatures, thereby determining their application range.
  •  
49.
  • Linder, David, et al. (författare)
  • Modeling confined ductile fracture – a void-growth and coalescence approach
  • Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
    • In a composite material a soft, ductile matrix can be confined by a hard, brittle phase, altering its deformation and fracture behavior. Increasing confinement leads to embrittlement of the matrix and, in turn, also the composite. From a materials design perspective, it is usually desired to avoid brittle fracture without compromising the hardness of the material. Understanding confined ductile fracture is therefore critical for modeling the mechanical response of composite materials with fine microstructure. The present work is focused on confined ductile fracture of a thin ductile film, with elasto-plastic power-law hardening behavior, sandwiched between ideal linear elastic substrates. Fracture of the ductile layer is modeled by growth and coalescence of prescribed voids in 2D. Influences of material properties, initial void volume fraction, geometric constraints and elastic mismatch are investigated. The results show a loss of ductility with decreasing film thickness that is accompanied by a severe decrease in fracture initiation toughness as well as an increased stress at the interface. The influence of materials properties is significant in all cases while the effect of initial void volume fraction is comparatively less critical for highly confined materials than for bulk materials. Increasing confinement also results in increasing normal stress at the phase interface, promoting interface decohesion prior to ductile fracture of the film. The present approach and results are a step towards more detailed prediction of composite fracture toughness and crack-growth resistance.
  •  
50.
  • Linder, David, et al. (författare)
  • Modeling confined ductile fracture - A void-growth and coalescence approach
  • 2020
  • Ingår i: International Journal of Solids and Structures. - : Elsevier BV. - 0020-7683 .- 1879-2146. ; 202, s. 454-462
  • Tidskriftsartikel (refereegranskat)abstract
    • In a composite material a soft, ductile matrix can be confined by a hard, brittle phase, altering its deformation and fracture behavior. Increasing confinement leads to embrittlement of the matrix and, in turn, also the composite. From a materials design perspective, it is usually desired to avoid brittle fracture without compromising the hardness of the material. Understanding confined ductile fracture is therefore critical for modeling the mechanical response of composite materials with fine microstructure. The present work is focused on confined ductile fracture of a thin ductile film, with elasto-plastic power-law hardening behavior, sandwiched between ideal linear elastic substrates. Fracture of the ductile layer is modeled by growth and coalescence of prescribed voids in 2D. Influences of material properties, initial void volume fraction, geometric constraints and elastic mismatch are investigated. The results show a loss of ductility with decreasing film thickness that is accompanied by a severe decrease in fracture initiation toughness as well as an increased stress at the interface. The influence of materials properties is significant in all cases while the effect of initial void volume fraction is comparatively less critical for highly confined materials than for bulk materials. Increasing confinement also results in increasing normal stress at the phase interface, promoting interface decohesion prior to ductile fracture of the film. The present approach and results are a step towards more detailed prediction of composite fracture toughness and crack-growth resistance.
  •  
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