1. |
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2. |
- Andersson, Carl-Henrik, et al.
(author)
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A Genetic Variant of the Sortilin 1 Gene isAssociated with Reduced Risk ofAlzheimer's Disease
- 2016
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In: Journal of Alzheimer's Disease. - 1387-2877 .- 1875-8908. ; 53:4, s. 1353-1363
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Journal article (peer-reviewed)abstract
- Alzheimer's disease (AD) is a neurodegenerative disorder represented by the accumulation of intracellular tau protein and extracellular deposits of amyloid-β (Aβ) in the brain. The gene sortilin 1 (SORT1) has previously been associated with cardiovascular disease in gene association studies. It has also been proposed to be involved in AD pathogenesis through facilitating Aβ clearance by binding apoE/Aβ complexes prior to cellular uptake. However, the neuropathological role of SORT1 in AD is not fully understood. To evaluate the associations between gene variants of SORT1 and risk of AD, we performed genetic analyses in a Swedish case-control cohort. Ten single nucleotide polymorphisms (SNPs), covering the whole SORT1 gene, were selected and genotyped in 620 AD patients and 1107 controls. The SNP rs17646665, located in a non-coding region of the SORT1 gene, remained significantly associated with decreased risk of AD after multiple testing (pc=0.0061). In addition, other SNPs were found to be nominally associated with risk of AD, as well as altered cognitive function and the CSF biomarker Aβ42, but these associations did not survive correction for multiple testing. The fact that SORT1 has been strongly associated with risk of cardiovascular disease is intriguing as cardiovascular disease is also regarded as a risk factor for AD. Finally, increased knowledge about SORT1 function has a potential to increase our understanding of APOE, the strongest risk factor for AD.
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3. |
- Andersson Sundén, Erik, et al.
(author)
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An assessment of nitrogen concentrations from spectroscopic measurements in the JET and ASDEX upgrade divertor
- 2019
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In: Nuclear Materials and Energy. - : Elsevier. - 2352-1791. ; 18, s. 147-152
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Journal article (peer-reviewed)abstract
- The impurity concentration in the tokamak divertor plasma is a necessary input for predictive scaling of divertor detachment, however direct measurements from existing tokamaks in different divertor plasma conditions are limited. To address this, we have applied a recently developed spectroscopic N II line ratio technique for measuring the N concentration in the divertor to a range of H-mode and L-mode plasma from the ASDEX Upgrade and JET tokamaks, respectively. The results from both devices show that as the power crossing the separatrix, P-sep, is increased under otherwise similar core conditions (e.g. density), a higher N concentration is required to achieve the same detachment state. For example, the N concentrations at the start of detachment increase from approximate to 2% to approximate to 9% as P-sep, is increased from approximate to 2.5 MW to approximate to 7 MW. These results tentatively agree with scaling law predictions (e.g. Goldston et al.) motivating a further study examining the parameters which affect the N concentration required to reach detachment. Finally, the N concentrations from spectroscopy and the ratio of D and N gas valve fluxes agree within experimental uncertainty only when the vessel surfaces are fully-loaded with N.
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4. |
- Bobkov, V, et al.
(author)
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Impact of ICRF on the scrape-off layer and on plasma wall interactions : From present experiments to fusion reactor
- 2019
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In: Nuclear Materials and Energy. - : Elsevier. - 2352-1791. ; 18, s. 131-140
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Journal article (peer-reviewed)abstract
- Recent achievements in studies of the effects of ICRF (Ion Cyclotron Range of Frequencies) power on the SOL (Scrape-Off Layer) and PWI (Plasma Wall Interactions) in ASDEX Upgrade (AUG), Alcator C-Mod, and JET-ILW are reviewed. Capabilities to diagnose and model the effect of DC biasing and associated impurity production at active antennas and on magnetic field connections to antennas are described. The experiments show that ICRF near-fields can lead not only to E x B convection, but also to modifications of the SOL density, which for Alcator C-Mod are limited to a narrow region near antenna. On the other hand, the SOL density distribution along with impurity sources can be tailored using local gas injection in AUG and JET-ILW with a positive effect on reduction of impurity sources. The technique of RF image current cancellation at antenna limiters was successfully applied in AUG using the 3-strap AUG antenna and extended to the 4-strap Alcator C-Mod field-aligned antenna. Multiple observations confirmed the reduction of the impact of ICRF on the SOL and on total impurity production when the ratio of the power of the central straps to the total antenna power is in the range 0.6 < P-cen / P-total < 0.8. Near-field calculations indicate that this fairly robust technique can be applied to the ITER ICRF antenna, enabling the mode of operation with reduced PWI. On the contrary, for the A2 antenna in JET-ILW the technique is hindered by RF sheaths excited at the antenna septum. Thus, in order to reduce the effect of ICRF power on PWI in a future fusion reactor, the antenna design has to be optimized along with design of plasmafacing components.
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5. |
- Bombarda, F., et al.
(author)
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Runaway electron beam control
- 2019
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In: Plasma Physics and Controlled Fusion. - : IOP Publishing. - 1361-6587 .- 0741-3335. ; 61:1
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Journal article (peer-reviewed)
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6. |
- Bonanomi, N., et al.
(author)
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Role of fast ion pressure in the isotope effect in JET L-mode plasmas
- 2019
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:9
-
Journal article (peer-reviewed)abstract
- This paper presents results of JET ITER-like wall L-mode experiments in hydrogen and deuterium (D) plasmas, dedicated to the study of the isotope dependence of ion heat transport by determination of the ion critical gradient and stiffness by varying the ion cyclotron resonance heating power deposition. When no strong role of fast ions in the plasma core is expected, the main difference between the two isotope plasmas is determined by the plasma edge and the core behavior is consistent with a gyro-Bohm scaling. When the heating power (and the fast ion pressure) is increased, in addition to the difference in the edge region, also the plasma core shows substantial changes. The stabilization of ion heat transport by fast ions, clearly visible in D plasmas, appears to be weaker in H plasmas, resulting in a higher ion heat flux in H with apparent anti-gyro-Bohm mass scaling. The difference is found to be caused by the different fast ion pressure between H and D plasmas, related to the heating power settings and to the different fast ion slowing down time, and is completely accounted for in non-linear gyrokinetic simulations. The application of the TGLF quasi-linear model to this set of data is also discussed.
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7. |
- Bravenec, R., et al.
(author)
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Benchmarking the GENE and GYRO codes through the relative roles of electromagnetic and E x B stabilization in JET high-performance discharges
- 2016
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In: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 58:12
-
Journal article (peer-reviewed)abstract
- Nonlinear gyrokinetic simulations using the GENE code have previously predicted a significant nonlinear enhanced electromagnetic stabilization in certain JET discharges with high neutral-beam power and low core magnetic shear (Citrin et al 2013 Phys. Rev. Lett. 111 155001, 2015 Plasma Phys. Control. Fusion 57 014032). This dominates over the impact of E x B flow shear in these discharges. Furthermore, fast ions were shown to be a major contributor to the electromagnetic stabilization. These conclusions were based on results from the GENE gyrokinetic turbulence code. In this work we verify these results using the GYRO code. Comparing results (linear frequencies, eigenfunctions, and nonlinear fluxes) from different gyrokinetic codes as a means of verification (benchmarking) is only convincing if the codes agree for more than one discharge. Otherwise, agreement may simply be fortuitous. Therefore, we analyze three discharges, all with a carbon wall: a simplified, two-species, circular geometry case based on an actual JET discharge; an L-mode discharge with a significant fast-ion pressure fraction; and a low-triangularity high-beta hybrid discharge. All discharges were analyzed at normalized toroidal flux coordinate rho = 0.33 where significant ion temperature peaking is observed. The GYRO simulations support the conclusion that electromagnetic stabilization is strong, and dominates E x B shear stabilization.
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8. |
- Carvalho, D. D., et al.
(author)
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Deep neural networks for plasma tomography with applications to JET and COMPASS
- 2019
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In: Journal of Instrumentation. - : Institute of Physics Publishing (IOPP). - 1748-0221. ; 14
-
Journal article (peer-reviewed)abstract
- Convolutional neural networks (CNNs) have found applications in many image processing tasks, such as feature extraction, image classification, and object recognition. It has also been shown that the inverse of CNNs, so-called deconvolutional neural networks, can be used for inverse problems such as plasma tomography. In essence, plasma tomography consists in reconstructing the 2D plasma profile on a poloidal cross-section of a fusion device, based on line-integrated measurements from multiple radiation detectors. Since the reconstruction process is computationally intensive, a deconvolutional neural network trained to produce the same results will yield a significant computational speedup, at the expense of a small error which can be assessed using different metrics. In this work, we discuss the design principles behind such networks, including the use of multiple layers, how they can be stacked, and how their dimensions can be tuned according to the number of detectors and the desired tomographic resolution for a given fusion device. We describe the application of such networks at JET and COMPASS, where at JET we use the bolometer system, and at COMPASS we use the soft X-ray diagnostic based on photodiode arrays.
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9. |
- Chankin, A. , V, et al.
(author)
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EDGE2D-EIRENE simulations of the influence of isotope effects and anomalous transport coefficients on near scrape-off layer radial electric field
- 2019
-
In: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 61:7
-
Journal article (peer-reviewed)abstract
- EDGE2D-EIRENE (the 'code') simulations show that radial electric field, Er, in the near scrape-off layer (SOL) of tokamaks can have large variations leading to a strong local E x B shear greatly exceeding that in the core region. This was pointed out in simulations of JET plasmas with varying divertor geometry, where the magnetic configuration with larger predicted near SOL E-r was found to have lower H-mode power threshold, suggesting that turbulence suppression in the SOL by local E. x. B shear can be a player in the L-H transition physics (Delabie et al 2015 42nd EPS Conf. on Plasma Physics (Lisbon, Portugal, 22-26 June 2015) paper O3.113 (http://ocs.ciemat.es/EPS2015PAP/pdf/O3.113.pdf), Chankin et al 2017 Nucl. Mater. Energy 12 273). Further code modeling of JET plasmas by changing hydrogen isotopes (H-D-T) showed that the magnitude of the near SOL E-r is lower in H cases in which the H-mode threshold power is higher (Chankin et al 2017 Plasma Phys. Control. Fusion 59 045012). From the experiment it is also known that hydrogen plasmas have poorer particle and energy confinement than deuterium plasmas, consistent with the code simulation results showing larger particle diffusion coefficients at the plasma edge, including SOL, in hydrogen plasmas (Maggi et al 2018 Plasma Phys. Control. Fusion 60 014045). All these experimental observations and code results support the hypothesis that the near SOL E x B shear can have an impact on the plasma confinement. The present work analyzes neutral ionization patterns of JET plasmas with different hydrogen isotopes in L-mode cases with fixed input power and gas puffing rate, and its impact on target electron temperature, T-e, and SOL E-r. The possibility of a self-feeding mechanism for the increase in the SOL E-r via the interplay between poloidal E x B drift and target T-e is discussed. It is also shown that reducing anomalous turbulent transport coefficients, particle diffusion and electron and ion heat conductivities, leads to higher peak target T-e and larger E-r, suggesting the possibility of a positive feedback loop, under an implicitly made assumption that the E x B shear in the SOL is capable of suppressing turbulence.
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10. |
- Craciunescu, Teddy, et al.
(author)
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Evaluation of reconstruction errors and identification of artefacts for JET gamma and neutron tomography
- 2016
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In: Review of Scientific Instruments. - : American Institute of Physics (AIP). - 0034-6748 .- 1089-7623. ; 87:1
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Journal article (peer-reviewed)abstract
- The Joint European Torus (JET) neutron profile monitor ensures 2D coverage of the gamma and neutron emissive region that enables tomographic reconstruction. Due to the availability of only two projection angles and to the coarse sampling, tomographic inversion is a limited data set problem. Several techniques have been developed for tomographic reconstruction of the 2-D gamma and neutron emissivity on JET, but the problem of evaluating the errors associated with the reconstructed emissivity profile is still open. The reconstruction technique based on the maximum likelihood principle, that proved already to be a powerful tool for JET tomography, has been used to develop a method for the numerical evaluation of the statistical properties of the uncertainties in gamma and neutron emissivity reconstructions. The image covariance calculation takes into account the additional techniques introduced in the reconstruction process for tackling with the limited data set (projection resampling, smoothness regularization depending on magnetic field). The method has been validated by numerically simulations and applied to JET data. Different sources of artefacts that may significantly influence the quality of reconstructions and the accuracy of variance calculation have been identified.
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11. |
- Garcia, J., et al.
(author)
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First principles and integrated modelling achievements towards trustful fusion power predictions for JET and ITER
- 2019
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In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:8
-
Journal article (peer-reviewed)abstract
- Predictability of burning plasmas is a key issue for designing and building credible future fusion devices. In this context, an important effort of physics understanding and guidance is being carried out in parallel to JET experimental campaigns in H and D by performing analyses and modelling towards an improvement of the understanding of DT physics for the optimization of the JET-DT neutron yield and fusion born alpha particle physics. Extrapolations to JET-DT from recent experiments using the maximum power available have been performed including some of the most sophisticated codes and a broad selection of models. There is a general agreement that 11-15 MW of fusion power can be expected in DT for the hybrid and baseline scenarios. On the other hand, in high beta, torque and fast ion fraction conditions, isotope effects could be favourable leading to higher fusion yield. It is shown that alpha particles related physics, such as TAE destabilization or fusion power electron heating, could be studied in ITER relevant JET-DT plasmas.
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12. |
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13. |
- Hellesen, Carl, et al.
(author)
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Validation of TRANSP Simulations Using Neutron emission Spectroscopy with Dual Sight Lines
- 2008
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In: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 79:10, s. 10E510-
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Journal article (peer-reviewed)abstract
- A method to generate modeled neutron spectra from bulk and fast ion distributions simulated by TRANSP has been developed. In this paper, modeled data generated from fuel ion distrubutions modeled with TRANSP is compared to measured data from two neutron spectrometers with different lines of sight; TOFOR with a radial one and the MPRu with a tangential one. The information obtained from the analysis of the measured neutron spectra such as the relative intensity of the emission from different ion populations places additional constraints on the simulation and can be used to adjust the parameters of the simulation.
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14. |
- Häll, Carl Henrik, 1978-, et al.
(author)
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The Integrated Dial-a-Ride Problem
- 2009
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In: Public Transport. - Berlin / Heidelberg : Springer. - 1866-749X .- 1613-7159. ; 1:1, s. 39-54
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Journal article (peer-reviewed)abstract
- In this paper we present a formulation of the Integrated Dial-a-Ride (IDARP). This problem is to schedule dial-a-ride requests, where some part of each journey may be carried out by a fixed route service. The IDARP is a generalization of the Dial-a-Ride Problem. An arc-based formulation is proposed, and it is shown how the model can be made easier to solve by arc elimination, variable substitution and the introduction of subtour elimination constraints. Small instances of the IDARP can be solved using an exact solution method, and one such instance is studied. We also describe how input and output data can be created and visualized in a geographic information system.
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15. |
- Kirschner, A., et al.
(author)
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Modelling of tungsten erosion and deposition in the divertor of JET-ILW in comparison to experimental findings
- 2019
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In: Nuclear Materials and Energy. - : Elsevier. - 2352-1791. ; 18, s. 239-244
-
Journal article (peer-reviewed)abstract
- The erosion, transport and deposition of tungsten in the outer divertor of JET-ILW has been studied for an H-Mode discharge with low frequency ELMs. For this specific case with an inter-ELM electron temperature at the strike point of about 20 eV, tungsten sputtering between ELMs is almost exclusively due to beryllium impurity and self-sputtering. However, during ELMs tungsten sputtering due to deuterium becomes important and even dominates. The amount of simulated local deposition of tungsten relative to the amount of sputtered tungsten in between ELMs is very high and reaches values of 99% for an electron density of 5E13 cm(-3) at the strike point and electron temperatures between 10 and 30 eV. Smaller deposition values are simulated with reduced electron density. The direction of the B-field significantly influences the local deposition and leads to a reduction if the E x B drift directs towards the scrape-off-layer. Also, the thermal force can reduce the tungsten deposition, however, an ion temperature gradient of about 0.1 eV/mm or larger is needed for a significant effect. The tungsten deposition simulated during ELMs reaches values of about 98% assuming ELM parameters according to free-streaming model. The measured WI emission profiles in between and within ELMs have been reproduced by the simulation. The contribution to the overall net tungsten erosion during ELMs is about 5 times larger than the one in between ELMs for the studied case. However, this is due to the rather low electron temperature in between ELMs, which leads to deuterium impact energies below the sputtering threshold for tungsten.
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16. |
- Kotschenreuther, M., et al.
(author)
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Gyrokinetic analysis and simulation of pedestals to identify the culprits for energy losses using 'fingerprints'
- 2019
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:9
-
Journal article (peer-reviewed)abstract
- Fusion performance in tokamaks hinges critically on the efficacy of the edge transport barrier (ETB) in suppressing energy losses. The new concept of 'fingerprints' is introduced to identify the instabilities that cause transport losses in the ETBs of many of today's experiments, from among widely posited candidates. Analysis of the gyrokinetic-Maxwell equations and gyrokinetic simulations of experiments reveals that each mode type produces characteristic ratios of transport in the various channels: density, heat, and impurities. This, together with experimental observations of transport in some channel or of the relative size of the driving sources of channels, can identify or determine the dominant modes causing energy transport. In multiple H-mode cases with edge-localized modes that are examined, these fingerprints indicate that magnetohydrodynamic (MHD)-like modes are apparently not the dominant agent of energy transport; rather, this role is played by micro-tearing modes (MTMs) and electron temperature gradient (ETG) modes, and in addition, possibly by ion temperature gradient/ trapped electron modes (ITG/TEM) on JET (Joint European 'Torus). MHD-like modes may dominate the electron particle losses. Fluctuation frequency can also be an important means of identification, and is often closely related to the transport fingerprint. The analytical arguments unify and explain previously disparate experimental observations on multiple devices, including DIII-D, JET, and ASDEX-U. Detailed simulations of two DIII-D ETBs also demonstrate and corroborate this.
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17. |
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18. |
- Maggi, C. F., et al.
(author)
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Isotope identity experiments in JET-ILW with H and D L-mode plasmas
- 2019
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In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:7
-
Journal article (peer-reviewed)abstract
- NBI-heated L-mode plasmas have been obtained in JET with the Be/W ITER-like wall (JET-ILW) in H and D, with matched profiles of the dimensionless plasma parameters, rho*, nu*, beta and q in the plasma core confinement region and same T-i/T-e and Z(eff). The achieved isotope identity indicates that the confinement scale invariance principle is satisfied in the core confinement region of these plasmas, where the dominant instabilities are Ion Temperature Gradient (ITG) modes. The dimensionless thermal energy confinement time, Omega(i) tau(E,th), and the scaled core plasma heat diffusivity, A chi(eff)/B-T, are identical in H and D within error bars, indicating lack of isotope mass dependence of the dimensionless L-mode thermal energy confinement time in JET-ILW. Predictive flux driven simulations with JETTO-TGLF of the H and D identity pair is in very good agreement with experiment for both isotopes: the stiff core heat transport, typical of JET-ILW NBI heated L-modes, overcomes the local gyro-Bohm scaling of gradient-driven TGLF, explaining the lack of isotope mass dependence in the confinement region of these plasmas. The effect of E x B shearing on the predicted heat and particle transport channels is found to be negligible for these low beta and low momentum input plasmas.
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19. |
- Nabais, F., et al.
(author)
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Energetic ion losses 'channeling' mechanism and strategy for mitigation
- 2019
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In: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 61:8
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Journal article (peer-reviewed)abstract
- Results from two different sets of JET experiments are presented. In experiments in which toroidicity-induced Alfven eigenmodes (TAEs) localized at different radial locations had the same frequencies and toroidal mode numbers, the occurrence of enhanced losses after the excitation of TAEs in the core of the plasma was observed. On the contrary, enhanced losses were not observed if the TAEs localized at different radial locations had different frequencies and toroidal mode numbers. Numerical modeling indicates that, in the first set of experiments, the enhanced losses were caused by a combined effect of the TAEs localized at different radial locations. The TAEs localized in the plasma core transported energetic ions from the core to outer regions of the plasma. Then, the TAEs localized in outer regions of the plasma interacted with these ions just transported by the core-localized TAEs causing a further radial displacement of the ions to the plasma edge. This process eventually ends up causing the loss of the resonant ions. In the second set of experiments, it was found that TAEs localized in the plasma core and in outer regions did not interact with the same ions and so no enhanced losses were measured. Sheared profiles of the safety factor combined with flat mass density profiles lead to larger differences on the frequencies of the TAEs localized at different radial locations, eventually avoiding loss of energetic ions through the described mechanism.
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20. |
- Neverov, V. S., et al.
(author)
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Determination of isotope ratio in the divertor of JET-ILW by high-resolution H alpha spectroscopy : H-D experiment and implications for D-T experiment
- 2019
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In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:4
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Journal article (peer-reviewed)abstract
- The data of the H alpha high-resolution spectroscopy, collected on the multiple lines of sight, which cover the entire divertor space in poloidal cross-section, during the recent hydrogen-deuterium experiments in JET-ILW (ITER-like wall), are processed. A strong spatial inhomogeneity of the hydrogen concentration, H/(H + D), in divertor is found in many pulses. Namely, the H/(H + D) ratio may be lower in the inner divertor than that in the outer divertor by the values of 0.15-0.35, depending on the conditions of gas puffing and plasma heating. This effect suggests the necessity of spatially-resolved measurements of isotope ratio in the divertor in the upcoming deuterium-tritium experiments. Also, separation of the overlapped T alpha and D alpha spectral lines is shown to be a challenging task especially when the local Doppler-broadened (Gaussian) line shapes are noticeably distorted by the net inward flux of fast non-Maxwellian neutral atoms. We use the respective, formerly developed model of an asymmetric spectral line shape, while analysing the data of the first deuterium-tritium experiment in JET-C (carbon wall), and test the model via comparing the isotope ratio results with another diagnostic's measurements. This model is shown to increase the accuracy of tritium concentration measurements in the divertor.
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21. |
- Nordanstig, Joakim, et al.
(author)
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Mortality with Paclitaxel-Coated Devices in Peripheral Artery Disease.
- 2020
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In: The New England journal of medicine. - : Massachusetts Medical Society. - 1533-4406 .- 0028-4793. ; 383, s. 2538-46
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Journal article (peer-reviewed)abstract
- The results of a recent meta-analysis aroused concern about an increased risk of death associated with the use of paclitaxel-coated angioplasty balloons and stents in lower-limb endovascular interventions for symptomatic peripheral artery disease.We conducted an unplanned interim analysis of data from a multicenter, randomized, open-label, registry-based clinical trial. At the time of the analysis, 2289 patients had been randomly assigned to treatment with drug-coated devices (the drug-coated-device group, 1149 patients) or treatment with uncoated devices (the uncoated-device group, 1140 patients). Randomization was stratified according to disease severity on the basis of whether patients had chronic limb-threatening ischemia (1480 patients) or intermittent claudication (809 patients). The single end point for this interim analysis was all-cause mortality.No patients were lost to follow-up. Paclitaxel was used as the coating agent for all the drug-coated devices. During a mean follow-up of 2.49 years, 574 patients died, including 293 patients (25.5%) in the drug-coated-device group and 281 patients (24.6%) in the uncoated-device group (hazard ratio, 1.06; 95% confidence interval, 0.92 to 1.22). At 1 year, all-cause mortality was 10.2% (117 patients) in the drug-coated-device group and 9.9% (113 patients) in the uncoated-device group. During the entire follow-up period, there was no significant difference in the incidence of death between the treatment groups among patients with chronic limb-threatening ischemia (33.4% [249 patients] in the drug-coated-device group and 33.1% [243 patients] in the uncoated-device group) or among those with intermittent claudication (10.9% [44 patients] and 9.4% [38 patients], respectively).In this randomized trial in which patients with peripheral artery disease received treatment with paclitaxel-coated or uncoated endovascular devices, the results of an unplanned interim analysis of all-cause mortality did not show a difference between the groups in the incidence of death during 1 to 4 years of follow-up. (Funded by the Swedish Research Council and others; ClinicalTrials.gov number, NCT02051088.).
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22. |
- Olander, Agnes, et al.
(author)
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Prediction of the Risk of Sepsis by Using Analysis of Plasma Glucose and Serum Lactate in Ambulance Services : A Prospective Study
- 2023
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In: Prehospital and Disaster Medicine. - : Cambridge University Press. - 1049-023X .- 1945-1938. ; 38:2, s. 160-167
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Journal article (peer-reviewed)abstract
- Introduction:The early recognition of patients with sepsis is difficult and the initial assessment outside of hospitals is challenging for ambulance clinicians (ACs). Indicators that ACs can use to recognize sepsis early are beneficial for patient outcomes. Research suggests that elevated point-of-care (POC) plasma glucose and serum lactate levels may help to predict sepsis in the ambulance service (AS) setting. Study Objective:The aim of this study was to test the hypothesis that the elevation of POC plasma glucose and serum lactate levels may help to predict Sepsis-3 in the AS. Methods:A prospective observational study was performed in the AS setting of Gothenburg in Sweden from the beginning of March 2018 through the end of September 2019. The criteria for sampling POC plasma glucose and serum lactate levels in the AS setting were high or intermediate risk according to the Rapid Emergency Triage and Treatment System (RETTS), as red, orange, yellow, and green if the respiratory rate was >22 breaths/minutes. Sepsis-3 were identified retrospectively. A primary and secondary analyses were carried out. The primary analysis included patients cared for in the AS and emergency department (ED) and were hospitalized. In the secondary analysis, patients who were only cared for in the AS and ED without being hospitalized were also included. To evaluate the predictive ability of these biomarkers, the area under the curve (AUC), sensitivity, specificity, and predictive values were used. Results:A total of 1,057 patients were included in the primary analysis and 1,841 patients were included in the secondary analysis. In total, 253 patients met the Sepsis-3 criteria (in both analyses). The AUC for POC plasma glucose and serum lactate levels showed low accuracy in predicting Sepsis-3 in both the primary and secondary analyses. Among all hospitalized patients, regardless of Sepsis-3, more than two-thirds had elevated plasma glucose and nearly one-half had elevated serum lactate when measured in the AS. Conclusions:As individual biomarkers, an elevated POC plasma glucose and serum lactate were not associated with an increased likelihood of Sepsis-3 when measured in the AS in this study. However, the high rate of elevation of these biomarkers before arrival in hospital highlights that their role in clinical decision making at this early stage needs further evaluation, including other endpoints than Sepsis-3.
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23. |
- Olander, Agnes, et al.
(author)
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Prediction of the Risk of Sepsis by Using Analysis of Plasma Glucose and Serum Lactate in Ambulance Services: A Prospective Study
- 2023
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In: Prehospital and Disaster Medicine. - : Cambridge University Press (CUP). - 1049-023X .- 1945-1938. ; 38:2, s. 160-167
-
Journal article (peer-reviewed)abstract
- Introduction: The early recognition of patients with sepsis is difficult and the initial assessment outside of hospitals is challenging for ambulance clinicians (ACs). Indicators that ACs can use to recognize sepsis early are beneficial for patient outcomes. Research suggests that elevated point-of-care (POC) plasma glucose and serum lactate levels may help to predict sepsis in the ambulance service (AS) setting. Study Objective: The aim of this study was to test the hypothesis that the elevation of POC plasma glucose and serum lactate levels may help to predict Sepsis-3 in the AS. Methods: A prospective observational study was performed in the AS setting of Gothenburg in Sweden from the beginning of March 2018 through the end of September 2019. The criteria for sampling POC plasma glucose and serum lactate levels in the AS setting were high or intermediate risk according to the Rapid Emergency Triage and Treatment System (RETTS), as red, orange, yellow, and green if the respiratory rate was >22 breaths/minutes. Sepsis-3 were identified retrospectively. A primary and secondary analyses were carried out. The primary analysis included patients cared for in the AS and emergency department (ED) and were hospitalized. In the secondary analysis, patients who were only cared for in the AS and ED without being hospitalized were also included. To evaluate the predictive ability of these biomarkers, the area under the curve (AUC), sensitivity, specificity, and predictive values were used. Results: A total of 1,057 patients were included in the primary analysis and 1,841 patients were included in the secondary analysis. In total, 253 patients met the Sepsis-3 criteria (in both analyses). The AUC for POC plasma glucose and serum lactate levels showed low accuracy in predicting Sepsis-3 in both the primary and secondary analyses. Among all hospitalized patients, regardless of Sepsis-3, more than two-thirds had elevated plasma glucose and nearly one-half had elevated serum lactate when measured in the AS. Conclusions: As individual biomarkers, an elevated POC plasma glucose and serum lactate were not associated with an increased likelihood of Sepsis-3 when measured in the AS in this study. However, the high rate of elevation of these biomarkers before arrival in hospital highlights that their role in clinical decision making at this early stage needs further evaluation, including other endpoints than Sepsis-3.
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24. |
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Overview of the JET results
- 2015
-
In: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 55:10
-
Journal article (peer-reviewed)
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25. |
- Pamela, S., et al.
(author)
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A wall-aligned grid generator for non-linear simulations of MHD instabilities in tokamak plasmas
- 2019
-
In: Computer Physics Communications. - : Elsevier. - 0010-4655 .- 1879-2944. ; 243, s. 41-50
-
Journal article (peer-reviewed)abstract
- Block-structured mesh generation techniques have been well addressed in the CFD community for automobile and aerospace studies, and their applicability to magnetic fusion is highly relevant, due to the complexity of the plasma-facing wall structures inside a tokamak device. Typically applied to non-linear simulations of MHD instabilities relevant to magnetically confined fusion, the JOREK code was originally developed with a 2D grid composed of isoparametric bi-cubic Bezier finite elements, that are aligned to the magnetic equilibrium of tokamak plasmas (the third dimension being represented by Fourier harmonics). To improve the applicability of these simulations, the grid-generator has been generalised to provide a robust extension method, using a block-structured mesh approach, which allows the simulations of arbitrary domains of tokamak vacuum vessels. Such boundary-aligned grids require the adaptation of boundary conditions along the edge of the new domain. Demonstrative non-linear simulations of plasma edge instabilities are presented to validate the robustness of the new grid, and future potential physics applications for tokamak plasmas are discussed. The methods presented here may be of interest to the wider community, beyond tokamak physics, wherever imposing arbitrary boundaries to quadrilateral finite elements is required.
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26. |
- Posada, Marcus, et al.
(author)
-
The integrated dial-a-ride problem with timetabled fixed route service
- 2017
-
In: Public Transport. - : Springer. - 1866-749X .- 1613-7159. ; 9:1-2, s. 217-241
-
Journal article (peer-reviewed)abstract
- This paper concerns operational planning of door-to-door transportation systems for the elderly and/or disabled, who often need a more flexible transportation system than the rest of the population. Highly flexible, but very costly direct transportation is often offered as a complement to standard fixed route public transport service. In the integrated dial-a-ride problem (IDARP), these modes of transport are combined and certain legs of the passengers journeys may be performed with the fixed route public transport system. We extend the IDARP and include timetables for the fixed route services, forcing the fleet of vehicles to schedule the arrival at transfer locations with care. Two mixed integer linear programming formulations of the integrated dial-a-ride problem with timetables are presented and analyzed. The key modeling challenge is that of the transfers between the fleet of vehicles and the fixed route public transport system. The formulations differ in how the transfers are modeled and the differences are thoroughly discussed. The computational study compares the formulations in terms of network size, computational time and memory usage and conclusions about their performances are drawn.
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27. |
- Rosén, Christoffer, 1986, et al.
(author)
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Increased Levels of Chitotriosidase and YKL-40 in Cerebrospinal Fluid from Patients with Alzheimer's Disease.
- 2014
-
In: Dementia and geriatric cognitive disorders extra. - : S. Karger AG. - 1664-5464. ; 4:2, s. 297-304
-
Journal article (peer-reviewed)abstract
- The cerebrospinal fluid (CSF) biomarkers total tau, abnormally phosphorylated tau and amyloid β 1-42 are strongly associated with Alzheimer's disease (AD). Apart from the pathologic hallmarks that these biomarkers represent, other processes such as inflammation and microglial activation are present in the brains of patients with AD. New biomarkers related to these processes could be valuable for the diagnosis and follow-up of AD patients and for the evaluation of inflammation-related pathologies.
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28. |
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29. |
- Silva, C., et al.
(author)
-
Geodesic acoustic mode evolution in L-mode approaching the L-H transition on JET
- 2019
-
In: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 61:7
-
Journal article (peer-reviewed)abstract
- Geodesic acoustic modes (GAMs) may generate strong oscillations in the radial electric field and therefore are considered as a possible trigger mechanism for the L-H transition. This contribution focuses on the characterization of GAMs in JET plasmas when approaching the L-H transition aiming at understanding their possible role in triggering the transition. GAM and turbulence characteristics are measured at the plasma edge using Doppler backscattering for different plasma current and line-averaged densities. The radial location of the GAM often moves further inside when neutral beam injection is applied possibly as a response to changes in the turbulence drive. GAMs are found to have modest amplitude at the transition except for high density discharges where GAMs are stronger, suggesting that the GAM is not responsible for facilitating the transition as the L-H power threshold also increases with density in the high density branch of the L-H transition. Our results suggest that the GAM alone does not play a leading role for causing the L-H transition at JET.
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30. |
- Varje, J., et al.
(author)
-
Synthetic diagnostic for the JET scintillator probe lost alpha measurements
- 2019
-
In: Journal of Instrumentation. - : Institute of Physics Publishing (IOPP). - 1748-0221. ; 14
-
Journal article (peer-reviewed)abstract
- A synthetic diagnostic has been developed for the JET lost alpha scintillator probe, based on the ASCOT fast ion orbit following code and the AFSI fusion source code. The synthetic diagnostic models the velocity space distribution of lost fusion products in the scintillator probe. Validation with experimental measurements is presented, where the synthetic diagnostic is shown to predict the gyroradius and pitch angle of lost DD protons and tritons. Additionally, the synthetic diagnostic reproduces relative differences in total loss rates in multiple phases of the discharge, which can be used as a basis for total loss rate predictions.
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31. |
- Weiland, M., et al.
(author)
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Simulation of neutron emission in neutral beam injection heated plasmas with the real-time code RABBIT
- 2019
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:8
-
Journal article (peer-reviewed)abstract
- In plasmas heated with deuterium beams a deficit of the expected fusion neutron rate is an indicator of the deterioration of the fast-ion confinement, caused, for instance, by magnetohydrodynamic instabilities. The capability of predicting this deficit during the discharge relies on the availability of real-time estimates of the neutron rate from NBI codes which must be fast and accurate at the same time. Therefore, the recently developed real-time RABBIT code for neutral beam injection (NBI) simulations has been extended to output the distribution function and calculate the neutron emission. After the description of this newly installed diagnostics in RABBIT, benchmarks with NUBEAM, a massively used and validated Monte Carlo NBI solver, are discussed on ASDEX-Upgrade and JET cases. A first application for control-room intershot analysis on DIII-D is presented, and the results are compared on a large database with a slower NUBEAM analysis. Further application possibilities, e.g. for real-time control of Alfven eigenmodes, are outlined.
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32. |
- Weiss, Lars, et al.
(author)
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BIOCOMPATIBILITY AND TOLERABILITY OF A PURELY BICARBONATE-BUFFERED PERITONEAL DIALYSIS SOLUTION
- 2009
-
In: Peritoneal Dialysis International. - 1718-4304 .- 0896-8608. ; 29:6, s. 647-655
-
Journal article (peer-reviewed)abstract
- Background: Novel peritoneal dialysis solutions are characterized by a minimal content of glucose degradation products and a neutral pH. Many studies have shown the biocompatibility of neutral lactate-buffered solutions; however, until now, the effect of purely bicarbonate-buffered solutions has not been intensively studied in vivo. Methods: This study was an open label, prospective, crossover multicenter trial to investigate the biocompatibility of a purely bicarbonate-buffered solution (bicPDF) by measuring biocompatibility parameters such as cancer antigen 125 (CA125) in peritoneal effluent. 55 patients were enrolled in the study. After a 2-week run-in phase, 53 patients could be randomized into 2 groups, starting with either standard lactate-buffered peritoneal dialysis fluid (SPDF) for 12 weeks (phase 1) and then switching to bicPDF for 12 weeks (phase 2), or vice versa. Overnight peritoneal effluents were collected at baseline and at the end of phases 1 and 2 and were tested for CA125, hyaluronic acid, vascular endothelial growth factor (VEGF), tumor necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6), interferon gamma (IFN gamma), and transforming growth factor-beta 1 (TGF-beta 1). Total ultrafiltration and residual renal function were also assessed. At the end of the study, pain during fluid exchange and dwell was evaluated using special questionnaires. Results: 34 patients completed the study; 27 of them provided data for analysis of the biocompatibility parameters. CA125 levels in overnight effluent were significantly higher with bicPDF (61.9 +/- 33.2 U/L) than with SPDF (18.6 +/- 18.2 U/L, p < 0.001). Hyaluronic acid levels were significantly lower after the use of bicPDF (185.0 +/- 119.6 ng/mL) than after SPDF (257.4 +/- 174.0 ng/mL, p = 0.013). Both TNF-alpha and TGF-beta 1 showed higher levels with the use of bicPDF than with SPDF. No differences were observed for IL-6, VEGF, or IFN gamma levels. We observed an improvement in the glomerular filtration rate with the use of bicPDF but no differences were observed for total fluid loss. Pain scores could be analyzed in 23 patients: there was no difference between the solutions. Conclusions: The use of a purely bicarbonate-buffered low-glucose degradation product solution significantly changes most of the peritoneal effluent markers measured, suggesting an improvement in peritoneal membrane integrity. Additionally, it seems to have a positive effect on residual renal function.
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33. |
- Zanca, P., et al.
(author)
-
A power-balance model of the density limit in fusion plasmas : application to the L-mode tokamak
- 2019
-
In: Nuclear Fusion. - : Institute of Physics Publishing (IOPP). - 0029-5515 .- 1741-4326. ; 59:12
-
Journal article (peer-reviewed)abstract
- A power-balance model, with radiation losses from impurities and neutrals, gives a unified description of the density limit (DL) of the stellarator, the L-mode tokamak, and the reversed field pinch (RFP). The model predicts a Sudo-like scaling for the stellarator, a Greenwald- like scaling, alpha I-p(8/9), for the RFP and the ohmic tokamak, a mixed scaling, alpha (PIp4/9)-I-4/9, for the additionally heated L-mode tokamak. In a previous paper (Zanca et al 2017 Nucl. Fusion 57 056010) the model was compared with ohmic tokamak, RFP and stellarator experiments. Here, we address the issue of the DL dependence on heating power in the L-mode tokamak. Experimental data from high-density disrupted L-mode discharges performed at JET, as well as in other machines, arc taken as a term of comparison. The model fits the observed maximum densities better than the pure Greenwald limit.
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34. |
-
- 2018
-
In: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 58:1
-
Research review (peer-reviewed)
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35. |
- Abayneh, Sisay A, et al.
(author)
-
Sensitivity of HIV-1 primary isolates to human anti-CD40 antibody-mediated suppression is related to co-receptor use
- 2008
-
In: AIDS Research and Human Retroviruses. - : Mary Ann Liebert Inc. - 1931-8405 .- 0889-2229. ; 24:3, s. 447-452
-
Journal article (peer-reviewed)abstract
- The effect of CD40 ligation on infection by HIV-1 primary isolates with different R5 phenotypes was evaluated with a novel set of anti-CD40 monoclonal antibodies originating from a human phage display library. Five human monoclonal anti-CD40 antibodies of IgG1 subtype characterized by the ability to activate B cells via CD40 were tested for induction of the CC-chemokines RANTES and MIP-1alpha and inhibition of HIV-1 replication in primary monocyte-derived macrophages (MDM). All activating anti-CD40 antibodies were able to induce CC-chemokines in MDM. We chose the most potent antibody, clone B44, for further experiments. This antibody had a suppressive effect on HIV-1 isolates of the R5 phenotype with limited use of CCR5/CXCR4 chimeric receptors. In comparison, HIV-1 isolates with broader use of CCR5/CXCR4 chimeric receptors or with CXCR4 use were less sensitive to anti-CD40-induced suppression. The results indicate that HIV-1 replication is inhibited by human anti-CD40 monoclonal antibodies through the mechanism of CC-chemokine induction. This effect is thus restricted to HIV-1 isolates sensitive to inhibition by CC-chemokines.
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36. |
- Aho-Mantila, L., et al.
(author)
-
Assessment of SOLPS5.0 divertor solutions with drifts and currents against L-mode experiments in ASDEX Upgrade and JET
- 2017
-
In: Plasma Physics and Controlled Fusion. - : IOP PUBLISHING LTD. - 0741-3335 .- 1361-6587. ; 59:3
-
Journal article (peer-reviewed)abstract
- The divertor solutions obtained with the plasma edge modelling tool SOLPS5.0 are discussed. The code results are benchmarked against carefully analysed L-mode discharges at various density levels with and without impurity seeding in the full-metal tokamaks ASDEX Upgrade and JET. The role of the cross-field drifts and currents in the solutions is analysed in detail, and the improvements achieved by fully activating the drift and current terms in view of matching the experimental signals are addressed. The persisting discrepancies are also discussed.
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37. |
- Aiba, N., et al.
(author)
-
Numerical analysis of ELM stability with rotation and ion diamagnetic drift effects in JET
- 2017
-
In: Nuclear Fusion. - : IOP PUBLISHING LTD. - 0029-5515 .- 1741-4326. ; 57:12
-
Journal article (peer-reviewed)abstract
- Stability to the type-I edge localized mode (ELM) in JET plasmas was investigated numerically by analyzing the stability to a peeling-ballooning mode with the effects of plasma rotation and ion diamagnetic drift. The numerical analysis was performed by solving the extended Frieman-Rotenberg equation with the MINERVA-DI code. To take into account these effects in the stability analysis self-consistently, the procedure of JET equilibrium reconstruction was updated to include the profiles of ion temperature and toroidal rotation, which are determined based on the measurement data in experiments. With the new procedure and MINERVA-DI, it was identified that the stability analysis including the rotation effect can explain the ELM trigger condition in JET with ITER like wall (JET-ILW), though the stability in JET with carbon wall (JET-C) is hardly affected by rotation. The key difference is that the rotation shear in JET-ILW plasmas analyzed in this study is larger than that in JET-C ones, the shear which enhances the dynamic pressure destabilizing a peeling-ballooning mode. In addition, the increase of the toroidal mode number of the unstable MHD mode determining the ELM trigger condition is also important when the plasma density is high in JET-ILW. Though such modes with high toroidal mode number are strongly stabilized by the ion diamagnetic drift effect, it was found that plasma rotation can sometimes overcome this stabilizing effect and destabilizes the peeling-ballooning modes in JET-ILW.
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38. |
- Ali, Alaa M. G., et al.
(author)
-
Alcohol Consumption and Survival after a Breast Cancer Diagnosis: A Literature-Based Meta-analysis and Collaborative Analysis of Data for 29,239 Cases
- 2014
-
In: Cancer Epidemiology Biomarkers & Prevention. - 1538-7755 .- 1055-9965. ; 23:6, s. 934-945
-
Journal article (peer-reviewed)abstract
- Background: Evidence for an association of alcohol consumption with prognosis after a diagnosis of breast cancer has been inconsistent. We have reviewed and summarized the published evidence and evaluated the association using individual patient data from multiple case cohorts. Methods: A MEDLINE search to identify studies published up to January 2013 was performed. We combined published estimates of survival time for "moderate drinkers" versus nondrinkers. An analysis of individual participant data using Cox regression was carried out using data from 11 case cohorts. Results: We identified 11 published studies suitable for inclusion in the meta-analysis. Moderate postdiagnosis alcohol consumption was not associated with overall survival [HR, 0.95; 95% confidence interval (CI), 0.85-1.05], but there was some evidence of better survival associated with prediagnosis consumption (HR, 0.80; 95% CI, 0.73-0.88). Individual data on alcohol consumption for 29,239 cases with 4,839 deaths were available from the 11 case cohorts, all of which had data on estrogen receptor (ER) status. For women with ER-positive disease, there was little evidence that pre-or postdiagnosis alcohol consumption is associated with breast cancer-specific mortality, with some evidence of a negative association with all-cause mortality. On the basis of a single study, moderate postdiagnosis alcohol intake was associated with a small reduction in breast cancer-specific mortality for women with ER-negative disease. There was no association with prediagnosis intake for women with ER-negative disease. Conclusion: There was little evidence that pre- or post-diagnosis alcohol consumption is associated with breast cancer-specific mortality for women with ER-positive disease. There was weak evidence that moderate post-diagnosis alcohol intake is associated with a small reduction in breast cancer-specific mortality in ER-negative disease. Impact: Considering the totality of the evidence, moderate postdiagnosis alcohol consumption is unlikely to have a major adverse effect on the survival of women with breast cancer. (C) 2014 AACR.
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39. |
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40. |
- Andersson, Carl-Henrik
(author)
-
The role of microglia in Alzheimer's disease - Investigating mechansims regulating amyloid-β clearance
- 2016
-
Doctoral thesis (other academic/artistic)abstract
- Alzheimer’s disease (AD) is the most common form of dementia today. The disease is characterized by the presence of amyloid plaques and neurofibrillary tangles in the brain, accompanied by a progressive neurodegeneration leading to memory loss. The underlying cause of the disease is largely unknown, but most evidence suggests that altered amyloid-β (Aβ) production is the putative cause of the disease. AD is also characterized by an inflammatory status in the CNS, although it is unclear whether the inflammation is the cause or the consequence of the disease. The aim of this thesis was to examine the role of microglia, the main immune cell in the brain, with regard to AD pathogenesis. This was carried out by experimental studies using the zebrafish as a model system in a combination with clinical analyses investigating biochemical differences and genetic variation in AD patients compared to controls. In paper I, we developed a novel zebrafish larvae model to study Aβ toxicity. The results indicated that injection with Aβ in animals leads to increased neurodegeneration and memory impairments, results similar to the pathological picture of AD. We also observed that oligomerization of the Aβ peptides was crucial for the neurotoxicity and that Aβ-induced neurodegeneration and memory impairments were mediated by separate pathways. In paper II, we used the newly developed zebrafish model to investigate how microglia interacts with injected Aβ. Confocal imaging revealed that microglia engulfs Aβ rapidly and that microglia is protective against Aβ-induced toxicity. Animals with reduced expression of microglia showed elevated levels of Aβ in the brain together with an increased neurodegeneration compared to controls. We also investigated the role of the p2y12 receptor and found that it plays a key role in the microglia-mediated clearance of Aβ in the brain. In paper III, we investigated genetic variation in the purinergic P2Y12 gene in a case-control study and found a haplotype to be associated with increased risk of AD. In paper IV, we performed a genetic analysis of SORT1, encoding sortilin 1, a receptor expressed on microglia, and identified a genetic variant strongly associated with a reduced risk of AD. In paper V, we identified two markers, chitotriosidase and YKL-40, both representing inflammation, to be upregulated in cerebrospinal fluid (CSF) of AD patients. In summary, we developed a new zebrafish model that can be used to study Aβ-induced pathology, where p2y12 was found to be protective against Aβ toxicity. Our data also suggest that AD patients have increased inflammation in the CNS and that P2Y12 together with SORT1 are possible risk genes for AD. This indicates that the zebrafish and humans share molecular mechanisms of neuroinflammation and our new model can in the future be used to explore new target genes for AD diagnosis and development of therapeutics.
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41. |
- Andersson, Henrik, et al.
(author)
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Assaying cardiac biomarkers for toxicity testing using biosensing and cardiomyocytes derived from human embryonic stem cells
- 2010
-
In: JOURNAL OF BIOTECHNOLOGY. - : Elsevier Science B.V., Amsterdam.. - 0168-1656 .- 1873-4863. ; 150:1, s. 175-181
-
Journal article (peer-reviewed)abstract
- Human embryonic stem cell (hESC) derived cardiomyocytes are in the present study being used for testing drug-induced cardiotoxicity in a biosensor set-up. The design of an in vitro testing alternative provides a novel opportunity to surpass previous methods based on rodent cells or cell lines due to its significantly higher toxicological relevance. In this report we demonstrate how hESC-derived cardiomyocytes release detectable levels of two clinically decisive cardiac biomarkers, cardiac troponin T and fatty acid binding protein 3, when the cardiac cells are exposed to the well-known cardioactive drug compound. doxorubicin. The release is monitored by the immuno-biosensor technique surface plasmon resonance, particularly appropriate due to its capacity for parallel and high-throughput analysis in complex media.
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42. |
- Andersson, Henrik, et al.
(author)
-
Monitoring of troponin release from cardiomyocytes during exposure to toxic substances using surface plasmon resonance biosensing
- 2010
-
In: ANALYTICAL AND BIOANALYTICAL CHEMISTRY. - : Springer Science Business Media. - 1618-2642 .- 1618-2650. ; 398:3, s. 1395-1402
-
Journal article (peer-reviewed)abstract
- Troponin T (TnT) is a useful biomarker for studying drug-induced toxicity effects on cardiac cells. We describe how a surface plasmon resonance (SPR) biosensor was applied to monitor the release of TnT from active HL-1 cardiomyocytes in vitro when exposed to cardiotoxic substances. Two monoclonal human TnT antibodies were compared in the SPR immunosensor to analyse the TnT release. The detection limit of TnT was determined to be 30 ng/ml in a direct assay set-up and to be 10 ng/ml in a sandwich assay format. Exposure of the cardiomyocytes to doxorubicin, troglitazone, quinidine and cobalt chloride for periods of 6 and 24 h gave significant SPR responses, whereas substances with low toxicity showed insignificant effects (ascorbic acid, methotrexate). The SPR results were verified with a validated immunochemiluminescence method which showed a correlation of r(2)=0.790.
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43. |
- Andersson, Kent, 1967-, et al.
(author)
-
Introduktion till Operationsanalys : En antologi med essäer av studerande i militärteknik 2011
- 2012
-
Other publication (other academic/artistic)abstract
- I ämnesplanen definieras militärteknik som ”den vetenskap som beskriver och förklarar hur tekniken inverkar på militär verksamhet på alla nivåer, strategisk, operativ och taktisk, samt hur officersprofessionen påverkar och påverkas av tekniken.”[1] En militärteknikers uppgift brukar, utgående från definitionen, uttryckas som att beskriva och förklara den militära nyttan med tekniken. För att kunna göra detta behövs verktyg. Och många av dem kommer från den vetenskapliga disciplinen Operationsanalys.Syftet med den här antologin är att introducera studerande i militärteknik på Försvarshögskolan till två av de mest refererade boktitlarna i operationsanalys – Methods for conducting military operational analysis editerad av Andrew G. Loerch och Larry B. Rainey samt Military Operations Research, quantitative decision making av N.K. Jaiswal.Kapitlen utgörs av essäer skrivna av studerande på den högre stabsofficersutbildningen med teknisk inriktning, som examinationsuppgift i en fördjupningskurs. Essäerna är till del referat av kapitel i de två böckerna ovan, men kryddade med exempel satta i svenskt sammanhang och med de studerandes egen värdering av metodernas användbarhet.[1]Försvarshögskolan, Ämnesplan militärteknik, 2007.
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44. |
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45. |
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46. |
- Andersson, Richard, 1990-
(author)
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Managerial Dilemmas of a Borderland Position : Professional Standardization in the Swedish School-age Educare
- 2023
-
Doctoral thesis (other academic/artistic)abstract
- The overarching aim of the thesis is to explore how local school management actors, i.e. school principals and municipal management staff, interpret and enact changes in their organizations following the demands and intentions derived from the teacher certification reform in Swedish School-age Educare. Through four individual research articles and a summary chapter, this compilation thesis focuses on the local organizing efforts and areas of conflict in enacting the initiatives of quality development and equivalence within the educational program. As a novel entity when compared to the institutional and professional properties of the neighboring school forms, and with little prior research into the managerial practice of the educational program, this thesis contributes to the understanding of professional standards-implementation and educational management outside of the compulsory school system. The thesis takes its theoretical point of departure in a symbolic interactionist approach toorganizational sensemaking – providing a framework for exploring actors’ interpretations, interactions and actions in making sense of the reform in relation to themselves, their organizations and extended environments. Guided by constructivist grounded theory methodology, the sub-studies ofthe thesis are carried out through case studies and qualitative interview studies.The main findings of the thesis show that managerial actors in Swedish School-age Educare interpret and enact the intentions and demands of the reform based on three co-constructive and dilemmatic factors that encompass the identity, quality and resource-based aspects of the educational program. Managers, across both the municipal and local school level, untangle and maneuver within and between these factors by means of contextual rationality and pragmatic problem-solving – resulting in a wide variation in outcomes between individual organizations. This is apparent incommon activities affected by the content of the reform, such as professional development of current staff, recruitment procedures and hiring routines and the re-structuring of staff responsibilities. As a result of this, issues arise in relation to the initial reform intentions and logic of qualitative equivalence through professional standardization in School-age Educare, with further implications for local managerial practice towards improvement and change in the educational program.
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47. |
- Andersson Sundén, Erik, et al.
(author)
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Evaluation of neutron spectrometer techniques for ITER using synthetic data
- 2013
-
In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 701, s. 62-71
-
Journal article (peer-reviewed)abstract
- A neutron spectrometer at ITER is expected to provide estimates of plasma parameters such as ion temperature, Ti, fuel ion ratio, nt/nd, and Qthermal/Qtot, with 10-20% precision at a time resolution, Δt, of at least 100 ms. The present paper describes a method for evaluating different neutron spectroscopy techniques based on their instrumental response functions and synthetic measurement data. We include five different neutron spectrometric techniques with realistic response functions, based on simulations and measurements where available. The techniques are magnetic proton recoil, thin-foil proton recoil, gamma discriminating organic scintillator, diamond and time-of-flight. The reference position and line of sight of a high resolution neutron spectrometer on ITER are used in the study. ITER plasma conditions are simulated for realistic operating scenarios. The ITER conditions evaluated are beam and radio frequency heated and thermal deuterium-tritium plasmas. Results are given for each technique in terms of the estimated time resolution at which the parameter determination can be made within the required precision (here 10% for Ti and the relative intensities of NB and RF emission components). It is shown that under the assumptions made, the thin-foil techniques out-perform the other spectroscopy techniques in practically all measurement situations. For thermal conditions, the range of achieved Δt in the determination of Ti varies in time scales from ms (for the magnetic and thin-foil proton recoil) to s (for gamma discriminating organic scintillator).
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48. |
- Andersson Sundén, Erik, et al.
(author)
-
Instrumentation for neutron emission spectrometry in use at JET
- 2010
-
In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 623:2, s. 681-685
-
Journal article (peer-reviewed)abstract
- The present contribution discusses two neutron spectrometers: the time-of-flight spectrometer (TOFOR) and the magnetic proton recoil spectrometer (MPRu). TOFOR uses fast plastic scintillators equipped with digital time-stamping electronics to register the time of each eligible scintillation event. The time trace for each detector is acquired practically dead-time free. The detectors of the MPRu are of phoswich type and each detector is connected to a digital transient recorder card that stores the full waveform for an event. By using phoswich detectors, pulse-shape discrimination techniques can be applied offline to distinguish signal events from background. A future upgrade of TOFOR could be digital “hybrid” cards, which store correlated time and waveform information. This information can be used to decrease the background level in the ttof spectrum, thereby increasing the operating range.
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49. |
- Andersson Sundén, Erik, et al.
(author)
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The thin-foil magnetic proton recoil neutron spectrometer MPRu at JET
- 2009
-
In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 610:3, s. 682-699
-
Journal article (peer-reviewed)abstract
- Neutrons are produced in fusion energy experiments with both deuterium (D) and deuterium–tritium (DT) plasmas. Neutron spectroscopy is a valuable tool in the study of the underlying fuel ion populations. The magnetic proton recoil neutron spectrometer, originally installed at JET in 1996 for 14-MeV neutron measurements, has been upgraded, with the main aim of improving its signal-to-background ratio (S/B), making measurements of the 2.5-MeV neutron emission in D plasmas possible. The upgrade includes a new focal-plane detector, based on the phoswich technique and consequently less sensitive to background, and a new custom-designed digital data acquisition system based on transient recorder cards. Results from JET show that the upgraded MPRu can measure 2.5-MeV neutrons with S/B=5, an improvement by a factor of 50 compared with the original MPR. S/B of 2.8×104 in future DT experiments is estimated. The performance of the MPRu is exemplified with results from recent D plasma operations at JET, concerning both measurements with Ohmic, ion cyclotron resonance (ICRH) and neutral beam injection (NBI) plasma heating, as well as measurements of tritium burn-up neutrons. The upgraded instrument allows for 2.5-MeV neutron emission and deuterium ion temperature measurements in plasmas with low levels of tritium, a feature necessary for the ITER experiment.
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50. |
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