| 1. |
- Joffrin, E., et al.
(författare)
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Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
- 2019
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:11
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Forskningsöversikt (refereegranskat)abstract
- For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D-T mixtures since 1997 and the first ever D-T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D-T campaign (DTE2). This paper addresses the key elements developed by the JET programme directly contributing to the D-T preparation. This intense preparation includes the review of the physics basis for the D-T operational scenarios, including the fusion power predictions through first principle and integrated modelling, and the impact of isotopes in the operation and physics of D-T plasmas (thermal and particle transport, high confinement mode (H-mode) access, Be and W erosion, fuel recovery, etc). This effort also requires improving several aspects of plasma operation for DTE2, such as real time control schemes, heat load control, disruption avoidance and a mitigation system (including the installation of a new shattered pellet injector), novel ion cyclotron resonance heating schemes (such as the three-ions scheme), new diagnostics (neutron camera and spectrometer, active Alfven eigenmode antennas, neutral gauges, radiation hard imaging systems...) and the calibration of the JET neutron diagnostics at 14 MeV for accurate fusion power measurement. The active preparation of JET for the 2020 D-T campaign provides an incomparable source of information and a basis for the future D-T operation of ITER, and it is also foreseen that a large number of key physics issues will be addressed in support of burning plasmas.
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| 3. |
- Krasilnikov, A., et al.
(författare)
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Evidence of 9 Be + p nuclear reactions during 2ω CH and hydrogen minority ICRH in JET-ILW hydrogen and deuterium plasmas
- 2018
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 58:2
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Tidskriftsartikel (refereegranskat)abstract
- The intensity of 9Be + p nuclear fusion reactions was experimentally studied during second harmonic (2ω CH) ion-cyclotron resonance heating (ICRH) and further analyzed during fundamental hydrogen minority ICRH of JET-ILW hydrogen and deuterium plasmas. In relatively low-density plasmas with a high ICRH power, a population of fast H+ ions was created and measured by neutral particle analyzers. Primary and secondary nuclear reaction products, due to 9Be + p interaction, were observed with fast ion loss detectors, γ-ray spectrometers and neutron flux monitors and spectrometers. The possibility of using 9Be(p, d)2α and 9Be(p, α)6Li nuclear reactions to create a population of fast alpha particles and study their behaviour in non-active stage of ITER operation is discussed in the paper.
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| 4. |
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| 5. |
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- 2018
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 58:1
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Forskningsöversikt (refereegranskat)
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| 25. |
- Abel, I, et al.
(författare)
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Overview of the JET results with the ITER-like wall
- 2013
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 53:10, s. 104002-
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Tidskriftsartikel (refereegranskat)abstract
- Following the completion in May 2011 of the shutdown for the installation of the beryllium wall and the tungsten divertor, the first set of JET campaigns have addressed the investigation of the retention properties and the development of operational scenarios with the new plasma-facing materials. The large reduction in the carbon content (more than a factor ten) led to a much lower Z(eff) (1.2-1.4) during L- and H-mode plasmas, and radiation during the burn-through phase of the plasma initiation with the consequence that breakdown failures are almost absent. Gas balance experiments have shown that the fuel retention rate with the new wall is substantially reduced with respect to the C wall. The re-establishment of the baseline H-mode and hybrid scenarios compatible with the new wall has required an optimization of the control of metallic impurity sources and heat loads. Stable type-I ELMy H-mode regimes with H-98,H-y2 close to 1 and beta(N) similar to 1.6 have been achieved using gas injection. ELM frequency is a key factor for the control of the metallic impurity accumulation. Pedestal temperatures tend to be lower with the new wall, leading to reduced confinement, but nitrogen seeding restores high pedestal temperatures and confinement. Compared with the carbon wall, major disruptions with the new wall show a lower radiated power and a slower current quench. The higher heat loads on Be wall plasma-facing components due to lower radiation made the routine use of massive gas injection for disruption mitigation essential.
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| 26. |
- Romanelli, F, et al.
(författare)
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Overview of the JET results
- 2011
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 51:9
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Tidskriftsartikel (refereegranskat)abstract
- Since the last IAEA Conference JET has been in operation for one year with a programmatic focus on the qualification of ITER operating scenarios, the consolidation of ITER design choices and preparation for plasma operation with the ITER-like wall presently being installed in JET. Good progress has been achieved, including stationary ELMy H-mode operation at 4.5 MA. The high confinement hybrid scenario has been extended to high triangularity, lower ρ*and to pulse lengths comparable to the resistive time. The steady-state scenario has also been extended to lower ρ*and ν*and optimized to simultaneously achieve, under stationary conditions, ITER-like values of all other relevant normalized parameters. A dedicated helium campaign has allowed key aspects of plasma control and H-mode operation for the ITER non-activated phase to be evaluated. Effective sawtooth control by fast ions has been demonstrated with3He minority ICRH, a scenario with negligible minority current drive. Edge localized mode (ELM) control studies using external n = 1 and n = 2 perturbation fields have found a resonance effect in ELM frequency for specific q95values. Complete ELM suppression has, however, not been observed, even with an edge Chirikov parameter larger than 1. Pellet ELM pacing has been demonstrated and the minimum pellet size needed to trigger an ELM has been estimated. For both natural and mitigated ELMs a broadening of the divertor ELM-wetted area with increasing ELM size has been found. In disruption studies with massive gas injection up to 50% of the thermal energy could be radiated before, and 20% during, the thermal quench. Halo currents could be reduced by 60% and, using argon/deuterium and neon/deuterium gas mixtures, runaway electron generation could be avoided. Most objectives of the ITER-like ICRH antenna have been demonstrated; matching with closely packed straps, ELM resilience, scattering matrix arc detection and operation at high power density (6.2 MW m-2) and antenna strap voltages (42 kV). Coupling measurements are in very good agreement with TOPICA modelling. © 2011 IAEA, Vienna.
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| 27. |
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| 28. |
- Zamora, Juan Carlos, et al.
(författare)
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Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
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Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
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| 29. |
- Axelsson, Robert, et al.
(författare)
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Evaluation of Multi-level Social Learning for Sustainable Landscapes : Perspective of a Development Initiative in Bergslagen, Sweden
- 2013
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Ingår i: Ambio. - : Springer Netherlands. - 0044-7447 .- 1654-7209. ; 42:2, s. 241-253
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Tidskriftsartikel (refereegranskat)abstract
- To implement policies about sustainable landscapes and rural development necessitates social learning about states and trends of sustainability indicators, norms that define sustainability, and adaptive multi-level governance. We evaluate the extent to which social learning at multiple governance levels for sustainable landscapes occur in 18 local development initiatives in the network of Sustainable Bergslagen in Sweden. We mapped activities over time, and interviewed key actors in the network about social learning. While activities resulted in exchange of experiences and some local solutions, a major challenge was to secure systematic social learning and make new knowledge explicit at multiple levels. None of the development initiatives used a systematic approach to secure social learning, and sustainability assessments were not made systematically. We discuss how social learning can be improved, and how a learning network of development initiatives could be realized.
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| 30. |
- Bosveld, Fred C., et al.
(författare)
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The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part B : Results and Process Understanding
- 2014
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Ingår i: Boundary-layer Meteorology. - : Springer Science and Business Media LLC. - 0006-8314 .- 1573-1472. ; 152:2, s. 157-187
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Tidskriftsartikel (refereegranskat)abstract
- We describe and analyze the results of the third global energy and water cycle experiment atmospheric boundary layer Study intercomparison and evaluation study for single-column models. Each of the nineteen participating models was operated with its own physics package, including land-surface, radiation and turbulent mixing schemes, for a full diurnal cycle selected from the Cabauw observatory archive. By carefully prescribing the temporal evolution of the forcings on the vertical column, the models could be evaluated against observations. We focus on the gross features of the stable boundary layer (SBL), such as the onset of evening momentum decoupling, the 2-m minimum temperature, the evolution of the inertial oscillation and the morning transition. New process diagrams are introduced to interpret the variety of model results and the relative importance of processes in the SBL; the diagrams include the results of a number of sensitivity runs performed with one of the models. The models are characterized in terms of thermal coupling to the soil, longwave radiation and turbulent mixing. It is shown that differences in longwave radiation schemes among the models have only a small effect on the simulations; however, there are significant variations in downward radiation due to different boundary-layer profiles of temperature and humidity. The differences in modelled thermal coupling to the land surface are large and explain most of the variations in 2-m air temperature and longwave incoming radiation among models. Models with strong turbulent mixing overestimate the boundary-layer height, underestimate the wind speed at 200 m, and give a relatively large downward sensible heat flux. The result is that 2-m air temperature is relatively insensitive to turbulent mixing intensity. Evening transition times spread 1.5 h around the observed time of transition, with later transitions for models with coarse resolution. Time of onset in the morning transition spreads 2 h around the observed transition time. With this case, the morning transition appeared to be difficult to study, no relation could be found between the studied processes, and the variation in the time of the morning transition among the models.
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| 31. |
- Boy, M., et al.
(författare)
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Interactions between the atmosphere, cryosphere, and ecosystems at northern high latitudes
- 2019
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 19:3, s. 2015-2061
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Tidskriftsartikel (refereegranskat)abstract
- The Nordic Centre of Excellence CRAICC (Cryosphere-Atmosphere Interactions in a Changing Arctic Climate), funded by NordForsk in the years 2011-2016, is the largest joint Nordic research and innovation initiative to date, aiming to strengthen research and innovation regarding climate change issues in the Nordic region. CRAICC gathered more than 100 scientists from all Nordic countries in a virtual centre with the objectives of identifying and quantifying the major processes controlling Arctic warming and related feedback mechanisms, outlining strategies to mitigate Arctic warming, and developing Nordic Earth system modelling with a focus on short-lived climate forcers (SLCFs), including natural and anthropogenic aerosols. The outcome of CRAICC is reflected in more than 150 peer-reviewed scientific publications, most of which are in the CRAICC special issue of the journal Atmospheric Chemistry and Physics. This paper presents an overview of the main scientific topics investigated in the centre and provides the reader with a state-of-the-art comprehensive summary of what has been achieved in CRAICC with links to the particular publications for further detail. Faced with a vast amount of scientific discovery, we do not claim to completely summarize the results from CRAICC within this paper, but rather concentrate here on the main results which are related to feedback loops in climate change-cryosphere interactions that affect Arctic amplification.
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| 32. |
- Bucardo, Filemon, et al.
(författare)
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Pediatric norovirus GII.4 infections in Nicaragua, 1999-2015
- 2017
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Ingår i: Infection, Genetics and Evolution. - : ELSEVIER SCIENCE BV. - 1567-1348 .- 1567-7257. ; 55, s. 305-312
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Investigate clinical and epidemiological factors of pediatric GII.4 norovirus infections in children with acute gastroenteritis (AGE) in Nicaragua between 1999 and 2015. Methods: We retrospectively analyzed laboratory and epidemiologic data from 1,790 children amp;lt;= 7 years with AGE from 6 hospitals in Nicaragua (n = 538), and 3 community clinics (n = 919) and households (n = 333) in Leon, between 1999 and 2015. Moreover, asymptomatic children from community clinics (n = 162) and households (n = 105) were enrolled. Norovirus was detected by real-time PCR and genotyped by sequencing the N-terminal and shell region of the capsid gene. Results: Norovirus was found in 19% (n = 338) and 12% (n = 32) of children with and without AGE, respectively. In total, 20 genotypes including a tentatively new genotype were detected. Among children with AGE, the most common genotypes were GII.4 (53%), GII.14 (7%), GII.3 (6%) and GI.3 (6%). In contrast, only one (1.4%) GII.4 was found in asymptomatic children. The prevalence of GII.4 infections was significantly higher in children between 7 and 12 months of age. The prevalence of GII.4 was lowest in households (38%), followed by community clinics (50%) and hospitals (75%). Several different GII.4 variants were detected and their emergence followed the global temporal trend. Conclusions: Overall our study found the predominance of pediatric GII.4 norovirus infections in Nicaragua mostly occurring in children between 7 and 12 months of age, implicating GII.4 as the main norovirus vaccine target.
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| 33. |
- Cadrin-Tourigny, Julia, et al.
(författare)
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A new prediction model for ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy
- 2019
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Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 1522-9645 .- 0195-668X. ; 40:23, s. 1850-1858
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) is characterized by ventricular arrhythmias (VAs) and sudden cardiac death (SCD). We aimed to develop a model for individualized prediction of incident VA/SCD in ARVC patients. METHODS AND RESULTS: Five hundred and twenty-eight patients with a definite diagnosis and no history of sustained VAs/SCD at baseline, aged 38.2 ± 15.5 years, 44.7% male, were enrolled from five registries in North America and Europe. Over 4.83 (interquartile range 2.44-9.33) years of follow-up, 146 (27.7%) experienced sustained VA, defined as SCD, aborted SCD, sustained ventricular tachycardia, or appropriate implantable cardioverter-defibrillator (ICD) therapy. A prediction model estimating annual VA risk was developed using Cox regression with internal validation. Eight potential predictors were pre-specified: age, sex, cardiac syncope in the prior 6 months, non-sustained ventricular tachycardia, number of premature ventricular complexes in 24 h, number of leads with T-wave inversion, and right and left ventricular ejection fractions (LVEFs). All except LVEF were retained in the final model. The model accurately distinguished patients with and without events, with an optimism-corrected C-index of 0.77 [95% confidence interval (CI) 0.73-0.81] and minimal over-optimism [calibration slope of 0.93 (95% CI 0.92-0.95)]. By decision curve analysis, the clinical benefit of the model was superior to a current consensus-based ICD placement algorithm with a 20.6% reduction of ICD placements with the same proportion of protected patients (P < 0.001). CONCLUSION: Using the largest cohort of patients with ARVC and no prior VA, a prediction model using readily available clinical parameters was devised to estimate VA risk and guide decisions regarding primary prevention ICDs (www.arvcrisk.com).
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| 34. |
- Cadrin-Tourigny, Julia, et al.
(författare)
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A new prediction model for ventricular arrhythmias in arrhythmogenic right ventricular cardiomyopathy
- 2022
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Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 43:32, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) is characterized by ventricular arrhythmias (VAs) and sudden cardiac death (SCD). We aimed to develop a model for individualized prediction of incident VA/SCD in ARVC patients. Methods and results: Five hundred and twenty-eight patients with a definite diagnosis and no history of sustained VAs/SCD at baseline, aged 38.2 ± 15.5 years, 44.7% male, were enrolled from five registries in North America and Europe. Over 4.83 (interquartile range 2.44-9.33) years of follow-up, 146 (27.7%) experienced sustained VA, defined as SCD, aborted SCD, sustained ventricular tachycardia, or appropriate implantable cardioverter-defibrillator (ICD) therapy. A prediction model estimating annual VA risk was developed using Cox regression with internal validation. Eight potential predictors were pre-specified: Age, sex, cardiac syncope in the prior 6 months, non-sustained ventricular tachycardia, number of premature ventricular complexes in 24 h, number of leads with T-wave inversion, and right and left ventricular ejection fractions (LVEFs). All except LVEF were retained in the final model. The model accurately distinguished patients with and without events, with an optimism-corrected C-index of 0.77 [95% confidence interval (CI) 0.73-0.81] and minimal over-optimism [calibration slope of 0.93 (95% CI 0.92-0.95)]. By decision curve analysis, the clinical benefit of the model was superior to a current consensus-based ICD placement algorithm with a 20.3% reduction of ICD placements with the same proportion of protected patients (P < 0.001). Conclusion: Using the largest cohort of patients with ARVC and no prior VA, a prediction model using readily available clinical parameters was devised to estimate VA risk and guide decisions regarding primary prevention ICDs (www.arvcrisk.com).
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| 35. |
- Cadrin-Tourigny, Julia, et al.
(författare)
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Sudden Cardiac Death Prediction in Arrhythmogenic Right Ventricular Cardiomyopathy : A Multinational Collaboration
- 2021
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Ingår i: Circulation: Arrhythmia and Electrophysiology. - : Lippincott Williams & Wilkins. - 1941-3149 .- 1941-3084. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with ventricular arrhythmias (VA) and sudden cardiac death (SCD). A model was recently developed to predict incident sustained VA in patients with ARVC. However, since this outcome may overestimate the risk for SCD, we aimed to specifically predict life-threatening VA (LTVA) as a closer surrogate for SCD. Methods: We assembled a retrospective cohort of definite ARVC cases from 15 centers in North America and Europe. Association of 8 prespecified clinical predictors with LTVA (SCD, aborted SCD, sustained, or implantable cardioverter-defibrillator treated ventricular tachycardia >250 beats per minute) in follow-up was assessed by Cox regression with backward selection. Candidate variables included age, sex, prior sustained VA (≥30s, hemodynamically unstable, or implantable cardioverter-defibrillator treated ventricular tachycardia; or aborted SCD), syncope, 24-hour premature ventricular complexes count, the number of anterior and inferior leads with T-wave inversion, left and right ventricular ejection fraction. The resulting model was internally validated using bootstrapping. Results: A total of 864 patients with definite ARVC (40±16 years; 53% male) were included. Over 5.75 years (interquartile range, 2.77-10.58) of follow-up, 93 (10.8%) patients experienced LTVA including 15 with SCD/aborted SCD (1.7%). Of the 8 prespecified clinical predictors, only 4 (younger age, male sex, premature ventricular complex count, and number of leads with T-wave inversion) were associated with LTVA. Notably, prior sustained VA did not predict subsequent LTVA (P=0.850). A model including only these 4 predictors had an optimism-corrected C-index of 0.74 (95% CI, 0.69-0.80) and calibration slope of 0.95 (95% CI, 0.94-0.98) indicating minimal over-optimism. Conclusions: LTVA events in patients with ARVC can be predicted by a novel simple prediction model using only 4 clinical predictors. Prior sustained VA and the extent of functional heart disease are not associated with subsequent LTVA events.
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| 36. |
- Dellenmark-Blom, Michaela, et al.
(författare)
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Prevalence of Mental Health Problems, Associated Factors, and Health-Related Quality of Life in Children with Long-Gap Esophageal Atresia in Sweden
- 2023
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Ingår i: Journal of Pediatric Surgery. - : Elsevier. - 0022-3468 .- 1531-5037. ; 58:9, s. 1646-1655
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Tidskriftsartikel (refereegranskat)abstract
- Background: Children with long-gap esophageal atresia (LGEA) face a high risk of digestive and respiratory morbidity, but their mental health outcomes have not been investigated. We aimed to identify the prevalence of mental health problems in children with LGEA, associated factors and health-related quality of life (HRQOL).Methods: Twenty-six children with LGEA aged 3-17 were recruited nationwide in Sweden. One of their parents and adolescents aged 11-17 completed information on the child's mental health (Strength and Difficulties Questionnaire), generic (PedsQL 4.0) and condition-specific HRQOL (EA-QOL). Parents gave information on current child symptomatology. Mental health level was determined using validated norms; abnormal >= 90 percentile/borderline >= 80 percentile/normal. Elevated levels were considered borderline/abnormal. Data were analyzed using descriptives, correlation and Mann-Whitney-U test. Significance level was p < 0.05.Results: Twelve children with LGEA aged 3-17 (46%) had elevated scores of >= 1 mental health domain in parent-reports, whereas 2 adolescents (15%) in self-reports. In parent-reports, 31% of the children had elevated levels of peer relationship problems, with associated factors being child sex male (p = 0.037), airway infections (p = 0.002) and disturbed night sleep (p = 0.025). Similarly, 31% showed elevated levels of hyperactivity/inattention, and associated factors were male sex (p = 0.005), asthma (p = 0.028) and disturbed night sleep (p = 0.036). Elevated levels of emotional symptoms, seen in 20%, were related to swallowing difficulties (p = 0.038) and vomiting problems (p = 0.045). Mental health problems correlated negatively with many HRQOL domains (p < 0.05).Conclusions: Children with LGEA risk mental health difficulties according to parent-reports, especially peer relationship problems and hyperactivity/inattention, with main risk factors being male sex, airway problems and sleep disturbances. This should be considered in follow-up care and research, particularly since their mental health problems may impair HRQOL.
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| 37. |
- Hukkinen, Maria, et al.
(författare)
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Management strategies and treatment results of pediatric choledochal malformations in the Nordic countries
- 2020
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Ingår i: HPB. - : Elsevier BV. - 1365-182X. ; 22:1, s. 161-168
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Tidskriftsartikel (refereegranskat)abstract
- Background: Incidence and long-term outcomes of choledochal malformations (CMs) in children remain unclear. Methods: Clinical characteristics, operative details, complications, and follow-up data were collected from eight pediatric surgical centers in Sweden, Norway, Denmark, and Finland, which also answered a questionnaire addressing management practices. Results: During 2000–2017, 126 pediatric CMs were diagnosed, corresponding an incidence of 1:37,400. Diagnostic, treatment, and follow-up practices varied markedly. Of patients with complete clinical data (n = 119), 85% and 11% had type I and IV CMs and were managed by open hepaticojejunostomy at median age of 2.5 (interquartile range 0.46–5.8) years. Associated malformations were more common in fusiform and type IV (23%) than cystic CMs (8%, p = 0.043). Pancreaticobiliary maljunction was more frequently confirmed in patients presenting with pancreatitis (26% vs. 7%, p = 0.005) and with fusiform CMs (56% vs. 25%, p = 0.001). Cholangitis/pancreatitis episodes, occurring in 12% during postoperative follow-up of 4.0 (2.0–7.9) years, associated with longer surveillance (OR 1.32, 95% CI 1.13–1.54, p < 0.001). However, only two thirds of centers continued follow-up until adulthood. No malignancies were reported. Conclusions: CM incidence was higher than traditionally reported among Western populations. Although open hepaticojejunostomy carries good short-term outcomes, long-term morbidity is noteworthy. Standardized evidence-based management strategies and long-term follow-up are encouraged.
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| 38. |
- Karis, O., et al.
(författare)
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High-kinetic-energy photoemission spectroscopy of Ni at 1s: 6-eV satellite at 4 eV
- 2008
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121 .- 1550-235X. ; 78:23, s. 3-3
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Tidskriftsartikel (refereegranskat)abstract
- Electron correlations are responsible for many profound phenomena in solid-state physics. A classical example is the 6-eV satellite in the photoelectron spectrum of Ni. Until now the satellite structure has only been investigated at the L shell and more shallow levels. Here we report a high-kinetic-energy photoemission spectroscopy (HIKE) investigation of Ni metal. We present 1s and 2p photoelectron spectra, obtained using excitation energies up to 12.6 keV. Our investigation demonstrates that the energy position of the satellite relative to the main line is different for the 1s and the 2p levels. In combination with electronic structure calculations, we show that this energy shift is attributed to unique differences in the core-valence coupling for the K and L-2,L-3 shells in 3d transition metals, resulting in different screening of the core holes.
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| 39. |
- Litjens, Carlijn H. C., et al.
(författare)
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Physiologically-Based Pharmacokinetic Modelling to Predict the Pharmacokinetics and Pharmacodynamics of Linezolid in Adults and Children with Tuberculous Meningitis
- 2023
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Ingår i: Antibiotics. - : MDPI. - 2079-6382. ; 12:4
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Tidskriftsartikel (refereegranskat)abstract
- Linezolid is used off-label for treatment of central nervous system infections. However, its pharmacokinetics and target attainment in cranial cerebrospinal fluid (CSF) in tuberculous meningitis patients is unknown. This study aimed to predict linezolid cranial CSF concentrations and assess attainment of pharmacodynamic (PD) thresholds (AUC:MIC of >119) in plasma and cranial CSF of adults and children with tuberculous meningitis. A physiologically based pharmacokinetic (PBPK) model was developed to predict linezolid cranial CSF profiles based on reported plasma concentrations. Simulated steady-state PK curves in plasma and cranial CSF after linezolid doses of 300 mg BID, 600 mg BID, and 1200 mg QD in adults resulted in geometric mean AUC:MIC ratios in plasma of 118, 281, and 262 and mean cranial CSF AUC:MIC ratios of 74, 181, and 166, respectively. In children using similar to 10 mg/kg BID linezolid, AUC:MIC values at steady-state in plasma and cranial CSF were 202 and 135, respectively. Our model predicts that 1200 mg per day in adults, either 600 mg BID or 1200 mg QD, results in reasonable (87%) target attainment in cranial CSF. Target attainment in our simulated paediatric population was moderate (56% in cranial CSF). Our PBPK model can support linezolid dose optimization efforts by simulating target attainment close to the site of TBM disease.
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| 40. |
- Litjens, Carlijn H. C., et al.
(författare)
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Prediction of Moxifloxacin Concentrations in Tuberculosis Patient Populations by Physiologically Based Pharmacokinetic Modeling
- 2022
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Ingår i: Journal of clinical pharmacology. - : John Wiley & Sons. - 0091-2700 .- 1552-4604. ; 62:3, s. 385-396
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Tidskriftsartikel (refereegranskat)abstract
- Moxifloxacin has an important role in the treatment of tuberculosis (TB). Unfortunately, coadministration with the cornerstone TB drug rifampicin results in suboptimal plasma exposure. We aimed to gain insight into the moxifloxacin pharmacokinetics and the interaction with rifampicin. Moreover, we provided a mechanistic framework to understand moxifloxacin pharmacokinetics. We developed a physiologically based pharmacokinetic model in Simcyp version 19, with available and newly generated in vitro and in vivo data, to estimate pharmacokinetic parameters of moxifloxacin alone and when administered with rifampicin. By combining these strategies, we illustrate that the role of P-glycoprotein in moxifloxacin transport is limited and implicate MRP2 as transporter of moxifloxacin-glucuronide followed by rapid hydrolysis in the gut. Simulations of multiple dose area under the plasma concentration-time curve (AUC) of moxifloxacin (400 mg once daily) with and without rifampicin (600 mg once daily) were in accordance with clinically observed data (predicted/observed [P/O] ratio of 0.87 and 0.80, respectively). Importantly, increasing the moxifloxacin dose to 600 mg restored the plasma exposure both in actual patients with TB as well as in our simulations. Furthermore, we extrapolated the single dose model to pediatric populations (P/O AUC ratios, 1.04-1.52) and the multiple dose model to children with TB (P/O AUC ratio, 1.51). In conclusion, our combined approach resulted in new insights into moxifloxacin pharmacokinetics and accurate simulations of moxifloxacin exposure with and without rifampicin. Finally, various knowledge gaps were identified, which may be considered as avenues for further physiologically based pharmacokinetic refinement.
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| 41. |
- Maret-Ouda, John, et al.
(författare)
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Aspiration pneumonia after antireflux surgery among neurologically impaired children with GERD
- 2020
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Ingår i: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 55:11, s. 2408-2412
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND OBJECTIVE: Aspiration pneumonia is a common and serious complication to gastroesophageal reflux disease (GERD) among neurologically impaired children. Medication of GERD does not effectively prevent aspiration pneumonia, and whether antireflux surgery with fundoplication is better in this respect is uncertain. The objective was to determine whether fundoplication prevents aspiration pneumonia among children with neurological impairment and GERD.METHODS: This was a population-based cohort study from Denmark, Finland, Norway and Sweden, consisting of neurologically impaired children with GERD who underwent fundoplication. The risk of aspiration pneumonia before fundoplication (preoperative person-time) was compared with the risk after surgery (postoperative person-time). Multivariable Cox regression provided hazard ratios (HRs) with 95% confidence intervals (CIs). Except for confounding adjusted for by means of the "crossover like" design, the HRs were adjusted for age, sex, year of entry and respiratory diseases.RESULTS: Among 578 patients (median age 3.5 years), the preoperative person-time was 956 years and the postoperative person-time was 3324 years. Fundoplication was associated with 56% decreased overall HR of aspiration pneumonia (HR 0.44, 95% CI 0.27-0.72), and the HRs decreased over time after surgery. The risk of other types of pneumonia than aspiration pneumonia was not clearly decreased after fundoplication (HR 0.79, 95% CI 0.59-1.08). The 30-day mortality rate was 0.7% and the complication rate was 3.6%.CONCLUSIONS: Antireflux surgery decreases, but does not eliminate, the risk of aspiration pneumonia among neurologically impaired children with GERD. Fundoplication may be a treatment option when aspiration pneumonia is a recurrent problem in these children.TYPE OF STUDY: Cohort study.LEVEL OF EVIDENCE: Prognosis study-level I.
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| 42. |
- Pakarinen, Mikko P, et al.
(författare)
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Outcomes of biliary atresia in the Nordic countries - a multicenter study of 158 patients during 2005-2016
- 2018
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Ingår i: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 53:8, s. 1509-1515
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Tidskriftsartikel (refereegranskat)abstract
- Background/purpose: Biliary atresia is the most common reason for newborn cholestasis and pediatric liver transplantation. Even after normalization of serum bilirubin after portoenterostomy, most patients require liver transplantation by adulthood due to expanding fibrosis. We addressed contemporary outcomes of biliary atresia in the Nordic countries. Methods: Data on center and patients characteristics, diagnostic practices, surgical treatment, adjuvant medical therapy after portoenterostomy, follow-up and outcomes were collected from all the Nordic centers involved with biliary atresia care during 2005-2016. Results: Of the 154 patients, 148 underwent portoenterostomy mostly by assigned surgical teams at median age of 64 (interquartile range 37-79) days, and 95 patients (64%) normalized their serum bilirubin concentration while living with native liver. Postoperative adjuvant medical therapy, including steroids, ursodeoxycholic acid and antibiotics was given to 137 (93%) patients. Clearance of jaundice associated with young age at surgery and favorable anatomic type of biliary atresia, whereas annual center caseload >. 3 patients and diagnostic protocol without routine liver biopsy predicted early performance of portoenterostomy. The cumulative 5-year native liver and overall survival estimate was 53% (95% CI 45-62) and 88% (95% CI 83-94), respectively. Portoenterostomy age <. 65. days and annual center caseload >. 3 patients were predictive for long-term native liver survival, while normalization of serum bilirubin after portoenterostomy was the major predictor of both native liver and overall 5-year survival. Conclusions: The outcomes of biliary atresia in the Nordic countries compared well with previous European studies. Further improvement should be pursued by active measures to reduce patient age at portoenterostomy. Retrospective prognosis study: Level II.
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| 43. |
- Palmer, C. N. A., et al.
(författare)
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Paradoxical Lower Serum Triglyceride Levels and Higher Type 2 Diabetes Mellitus Susceptibility in Obese Individuals with the PNPLA3 148M Variant
- 2012
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:6
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Tidskriftsartikel (refereegranskat)abstract
- Background: Obesity is highly associated with elevated serum triglycerides, hepatic steatosis and type 2 diabetes (T2D). The I148M (rs738409) genetic variant of patatin-like phospholipase domain-containing 3 gene (PNPLA3) is known to modulate hepatic triglyceride accumulation, leading to steatosis. No association between PNPLA3 I148M genotype and T2D in Europeans has been reported. Aim of this study is to examine the relationship between PNPLA3 I148M genotypes and serum triglycerides, insulin resistance and T2D susceptibility by testing a gene-environment interaction model with severe obesity. Methods and Findings: PNPLA3 I148M was genotyped in a large obese cohort, the SOS study (n = 3,473) and in the Go-DARTS (n = 15,448), a T2D case-control study. Metabolic parameters were examined across the PNPLA3 I148M genotypes in participants of the SOS study at baseline and at 2- and 10-year follow up after bariatric surgery or conventional therapy. The associations with metabolic parameters were validated in the Go-DARTS study. Serum triglycerides were found to be lower in the PNPLA3 148M carriers from the SOS study at baseline and from the Go-DARTS T2D cohort. An increased risk for T2D conferred by the 148M allele was found in the SOS study (O.R. 1.09, 95% C.I. 1.01-1.39, P = 0.040) and in severely obese individuals in the Go-DARTS study (O. R. 1.37, 95% C.I. 1.13-1.66, P = 0.001). The 148M allele was no longer associated with insulin resistance or T2D after bariatric surgery in the SOS study and no association with the 148M allele was observed in the less obese (BMI<35) individuals in the Go-DARTS study (P for interaction = 0.002). This provides evidence for the obesity interaction with 148M allele and T2D risk in a large-scale cross-sectional and a prospective interventional study. Conclusions: Severely obese individuals carrying the PNPLA3 148M allele have lower serum triglyceride levels, are more insulin resistant and more susceptible to T2D. This study supports the hypothesis that obesity-driven hepatic lipid accumulation may contribute to T2D susceptibility.
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| 44. |
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| 45. |
- Raoof, Mustafa, 1966-, et al.
(författare)
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Health-Related Quality-of-Life (HRQoL) on an Average of 12 Years After Gastric Bypass Surgery
- 2015
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Ingår i: Obesity Surgery. - : Springer Science and Business Media LLC. - 0960-8923 .- 1708-0428. ; 25:7, s. 1119-1127
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Tidskriftsartikel (refereegranskat)abstract
- It is evident that morbidly obese patients have a low health-related quality-of-life (HRQoL), and this low HRQoL has become a common reason for them to seek bariatric surgery. Several HRQoL studies demonstrate a dramatic postoperative improvement, but most of these have had a short follow-up period.An observational, cross-sectional study for HRQoL was conducted to study 486 patients (average age of 50.7 +/- 10.0 years, with 84 % of them being female) operated with gastric bypass (GBP) in the period 1993 to 2003 at the University Hospitals of A-rebro and Uppsala. Mean follow-up after gastric bypass was 11.5 +/- 2.7 years (range 7-17). Two HRQoL instruments were used, SF-36 and the Obesity-related Problems scale (OP). The study group was compared with two control groups, both matched for age and gender, one from the general population and one containing morbidly obese patients evaluated and awaiting bariatric surgery.The study group scored better in the SF-36 domains (all four physical domains and the vitality subscore) and OP scale compared to obese controls, but their HRQoL scores were lower than those of the general population. HRQoL was better among younger patients and in the following subgroups: men, patients with satisfactory weight loss, satisfied with the procedure, free from co-morbidities and gastrointestinal symptoms, employment, good oral status and those not hospitalised or regularly followed up for non-bariatric reasons.Long-term follow-up after GBP for morbid obesity showed better scores in most aspects of HRQoL compared to obese controls but did not achieve the levels of the general population. Patients with better medical outcome after gastric bypass operation had better HRQoL.
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| 46. |
- Ruge, T., et al.
(författare)
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Acute hyperinsulinemia raises plasma interleukin-6 in both nondiabetic and type 2 diabetes mellitus subjects, and this effect is inversely associated with body mass index
- 2009
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Ingår i: Metabolism. - 1532-8600 .- 1532-8600. ; 58:6, s. 860-6
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Tidskriftsartikel (refereegranskat)abstract
- Hyperinsulinemia is a characteristic of type 2 diabetes mellitus (T2DM) and is believed to play a role in the low-grade inflammation seen in T2DM. The main aim was to study the effect of hyperinsulinemia on adipokines in individuals with different levels of insulin resistance, glycemia, and obesity. Three groups of sex-matched subjects were studied: young healthy subjects (YS; n = 10; mean age, 26 years; body mass index [BMI], 22 kg/m(2)), patients with T2DM (DS; n = 10; 61 years; BMI, 27 kg/m(2)), and age- and BMI-matched controls to DS (CS; n = 10; 60 years; BMI, 27 kg/m(2)). Plasma concentrations of adipokines were measured during a hyperinsulinemic euglycemic clamp lasting 4 hours. Moreover, insulin-stimulated glucose uptake in isolated adipocytes was analyzed to address adipose tissue insulin sensitivity. Plasma interleukin (IL)-6 increased significantly (P < or = .01) in all 3 groups during hyperinsulinemia. However, the increase was smaller in both DS (P = .06) and CS (P < .05) compared with YS (approximately 2.5-fold vs approximately 4-fold). A significant increase of plasma tumor necrosis factor (TNF) alpha was observed only in YS. There were only minor or inconsistent effects on adiponectin, leptin, and high-sensitivity C-reactive protein levels during hyperinsulinemia. Insulin-induced rise in IL-6 correlated negatively to BMI (P = .001), waist to hip ratio (P = .05), and baseline (fasting) insulin (P = .03) and IL-6 (P = .02) levels and positively to insulin-stimulated glucose uptake in isolated adipocytes (P = .07). There was no association with age or insulin sensitivity. In a multivariate analysis, also including T2DM/no T2DM, an independent correlation (inverse) was found only between BMI and fold change of IL-6 (r(2) = 0.41 for model, P < .005). Hyperinsulinemia per se can produce an increase in plasma IL-6 and TNFalpha, and this can potentially contribute to the low-grade inflammation seen in obesity and T2DM. However, obesity seems to attenuate the ability of an acute increase in insulin to further raise circulating levels of IL-6 and possibly TNFalpha.
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| 47. |
- Stadil, Tatjana, et al.
(författare)
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Surgical repair of long-gap esophageal atresia : A retrospective study comparing the management of long-gap esophageal atresia in the Nordic countries
- 2019
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Ingår i: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 54:3, s. 423-428
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Tidskriftsartikel (refereegranskat)abstract
- Background:Several surgical procedures have been described in the reconstruction of long-gap esophageal atresia (LGEA). We reviewed the surgical methods used in children with LGEA in the Nordic countries over a 15-year period and the postoperative complications within the first postoperative year.Methods:Retrospective multicenter medical record review of all children born with Gross type A or B esophageal atresia between 01/01/2000 and 12/31/2014 reconstructed within their first year of life.Results:We included 71 children; 56 had Gross type A and 15 type B LGEA. Delayed primary anastomosis (DPA) was performed in 52.1% and an esophageal replacement procedure in 47.9%. Gastric pull-up (GPU) was the most frequent procedure (25.4%). The frequency of chromosomal abnormalities, congenital heart defects and other anomalies was significantly higher in patients who had a replacement procedure. The frequency of gastroesophageal reflux (GER) was significantly higher after DPA compared to esophageal replacement (p = 0.013). At 1-year follow-up the mean body weight was higher after DPA than after organ interposition (p = 0.043).Conclusion: DPA and esophageal replacement procedures were equally applied. Postoperative complications and follow-up were similar except for the development of GER and the body weight at 1-year follow-up. Long-term results should be investigated.Type of study:Treatment study.
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| 48. |
- Stadil, Tatjana, et al.
(författare)
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Surgical treatment and major complications within the first year of life in newborns with long-gap esophageal atresia gross type A and B : a systematic review
- 2019
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Ingår i: Journal of Pediatric Surgery. - : Elsevier BV. - 0022-3468 .- 1531-5037. ; 54:11, s. 2242-2249
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Forskningsöversikt (refereegranskat)abstract
- Background: The surgical repair of long-gap esophageal atresia (LGEA) is still a challenge and there is no consensus on the preferred method of reconstruction. We performed a systematic review of the surgical treatment of LGEA Gross type A and B with the primary aim to compare the postoperative complications related to the different methods within the first postoperative year.Methods: Systematic literature review on the surgical repair of LGEA Gross type A and B within the first year of life published from January 01, 1996 to November 01, 2016.Results: We included 57 artides involving a total of 326 patients of whom 289 had a Gross type A LGEA. Delayed primary anastomosis (DPA) was the most applied surgical method (68.4%) in both types, followed by gastric pull-up (GPU) (83%). Anastomotic stricture (53.7%), gastro-esophageal reflux (GER) (32.2%) and anastomotic leakage (22.7%) were the most common postoperative complications, with stricture and GER occurring more often after DPA (61.9% and 40.8% respectively) compared to other methods (p < 0.001).Conclusion: The majority of patients in this review were managed by DPA and postoperative complications were common despite the surgical method, with anastomotic stricture and GER being most common after DPA.
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| 49. |
- Svensson, Jan F
(författare)
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On the treatment of acute appendicitis in children
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Acute appendicitis is a common condition in children and the treatment of this condition is both straightforward and complex at the same time. An appendectomy is the most common acute surgical intervention in children and the vast majority of children make a swift recovery without any complications. The surgical modality is however shifting from open to minimal access surgery and now further onto non-operative treatment. A well-performed clinical examination is still imperative but is currently aided by both evolving scoring systems and imaging. Imaging is developing from ultrasound via computed tomography-scanning to magnetic resonance imaging. The traditional belief that an inflamed appendix always progresses to gangrene and perforation does not hold its ground. Spontaneous resolution of acute appendicitis appears to be common. The aim of this thesis was to present modern benchmarks of different treatment modalities of acute appendicitis today, to present current evidence of non-operative treatment of acute appendicitis and to test if non-operative treatment of acute appendicitis in children is safe and feasible. All clinical studies have been based on children treated at the Astrid Lindgren Children´s Hospital, Stockholm, Sweden. In paper I we conducted a review of all children who underwent an appendectomy for acute appendicitis between 2006 and 2010. 1744 patients were operated, 1009 had a laparoscopic operation. We found no difference in the rate of complications between the two methods. We found that the operating time was longer for laparoscopic surgery and that the initial assumption that the postoperative length of stay in the laparoscopic group was shorter than in the open group was not due to the surgical modality but to a general trend over time. In paper II we studied recurrence of acute appendicitis in children after successful non-operative treatment of an imaging-confirmed appendiceal abscess. 89 patients were included in this study. Nine patients had an appendectomy during the 5.1 years of follow-up but only 2 had a recurrent acute appendicitis. Hence, the recurrence rate was 2.4% during 5.1 years of follow-up. This finding supports the strategy of not performing interval appendectomies on a routine basis. In paper III we performed a meta-analysis on randomised controlled trials on non-operative treatment of acute appendicitis in adults. We included 4 trials with a total of 896 patients. There were no difference in treatment failure but there were fewer complications in the non-operative treatment group. 73% of patients were found not to have had an appendectomy during 1 year of follow-up. We concluded that a randomised controlled trial in children was warranted. In paper IV we conducted a randomised controlled pilot trial of non-operative treatment versus surgery of acute appendicitis in children. We enrolled 50 patients in the trial, 26 were randomised to surgery. In the surgery group, all patients had a histologically confirmed acute appendicitis; none of these patients had any significant complications. Of the patients treated non-operatively with antibiotics, 92% had initial resolution of symptoms and only one patient (5%) had recurrence of acute appendicitis during the one-year follow-up period. Overall, 62% of patients have not had an appendectomy during the follow-up.
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