| 1. |
- Eriksson, Frida, 1986, et al.
(författare)
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Interpretative and predictive modelling of Joint European Torus collisionality scans
- 2019
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Ingår i: Plasma Physics and Controlled Fusion. - : Institute of Physics Publishing (IOPP). - 0741-3335 .- 1361-6587. ; 61:11
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Tidskriftsartikel (refereegranskat)abstract
- Transport modelling of Joint European Torus (JET) dimensionless collisionality scaling experiments in various operational scenarios is presented. Interpretative simulations at a fixed radial position are combined with predictive JETTO simulations of temperatures and densities, using the TGLF transport model. The model includes electromagnetic effects and collisions as well as (E)over-right-arrow x (b)over-right-arrow shear in Miller geometry. Focus is on particle transport and the role of the neutral beam injection (NBI) particle source for the density peaking. The experimental 3-point collisionality scans include L-mode, and H-mode (D and H and higher beta D plasma) plasmas in a total of 12 discharges. Experimental results presented in (Tala et al 2017 44th EPS Conf.) indicate that for the H-mode scans, the NBI particle source plays an important role for the density peaking, whereas for the L-mode scan, the influence of the particle source is small. In general, both the interpretative and predictive transport simulations support the experimental conclusions on the role of the NBI particle source for the 12 JET discharges.
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| 2. |
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| 3. |
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| 4. |
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| 5. |
- 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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| 6. |
- Rajan, S., et al.
(författare)
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The Niebauer-Cutter prosthesis in excision arthroplasty of the trapezium
- 1982
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Ingår i: Journal of Hand Surgery, European Volume. - : Sage Publications. - 1753-1934 .- 2043-6289. ; 14:3, s. 295-303
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Tidskriftsartikel (refereegranskat)abstract
- Sixteen patients had excision arthroplasty of the trapezium, using the Niebauer-Cutter prosthesis. The average period of postoperative follow-up was thirteen months. All patients had severe preoperative disabilities and the majority were relieved from resting pain and pain during active use of their hands. The postoperative range of motion with regard to the palmar and radial abduction was found to be satisfactory, while varying degrees of limitation of circumduction was the rule. There was no correlation between the patients' own judgment of the postoperative benefits and the objectively measured range of motion. One patient had a luxation of the prosthesis, while another had a subluxation when opposing the thumb. This frequency of luxation/subluxation seems to be less than that experienced with the other common type of prosthesis, the Swanson prosthesis. Although it is obvious that the ideal prosthesis for treatment of disabilities in the carpometacarpal joint of the thumb is still not available, it was concluded that the Niebauer-Cutter prosthesis is the best choice at the present.
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| 7. |
- Rubboli, Andrea, et al.
(författare)
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Esperienza iniziale sulluso di abciximab nel trattamento di salvataggio della trombosi coronarica acuta nel Laboratorio di Emodinamica [Initial experience with the use of abciximab in the salvage treatment of acute coronary thrombosis in the Hemodynamics Laboratory]
- 1998
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Ingår i: Cardiologia (Rome, Italy). - 0393-1978. ; 43:11, s. 1221-1229
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- The optimal treatment of acute thrombotic complications in the Catheterization Laboratory has not been defined yet, due to the limited efficacy shown by various pharmacological regimens, even when associated to coronary angioplasty (PTCA). The aim of our study was therefore to evaluate the effects of abciximab (ReoPro), a new potent inhibitor of the platelet glycoprotein IIb/IIIa, when administered as a rescue treatment for acute thrombotic coronary occlusion during diagnostic or interventional procedures. Sixteen patients (12 males, 4 females, mean age 59.3 +/- 9.2 years, range 43-77 years), with unstable angina and consecutively treated with abciximab due to clinical instability attributable to coronary thrombosis angiographically proven during PTCA (9 cases) or diagnostic angiography (7 cases), were identified. The individual angiographic films and medical records were then reviewed in order to evaluate the effects of treatment on coronary flow, thrombus size and occurrence of in-hospital adverse events: death, non-fatal acute myocardial infarction (AMI), need for urgent myocardial revascularization and hemorrhage. The administration of abciximab, in association with PTCA (associated in turn with stent implantation in 8 cases), induced a significant increase of coronary TIMI flow grade (0.3 +/- 0.6 vs 2.4 +/- 0.9; p less than 0.05) and a significant decrease of thrombus score (size) 2.4 +/- 0.9 vs 1.3 +/- 0.6; p less than 0.01). No deaths nor need for urgent myocardial revascularization were observed; in 31% of cases (5 patients) evolution towards AMI occurred, while however 94% of cases (15 patients) had a coronary occlusion before treatment. No major hemorrhagic complications were observed, while in 12% of cases (2 patients) a groin hematoma associated with moderate hemoglobin drop, developed. In conclusion, the administration of abciximab, associated with the common rescue interventional procedures, in patients with acute thrombotic coronary occlusion in the Catheterization Laboratory, appears to be effective in restoring adequate coronary flow and reducing the thrombus size (limiting therefore the evolution towards AMI), and safe, not having been associated with significant hemorrhagic complications.
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| 8. |
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| 9. |
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| 10. |
- Aspelin, P., et al.
(författare)
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Cost-effectiveness of iodixanol in patients at high risk of contrast-induced nephropathy
- 2005
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Ingår i: American Heart Journal. - : Elsevier BV. - 0002-8703 .- 1097-6744. ; 149:2, s. 298-303
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Forskningsöversikt (refereegranskat)abstract
- Background: Acute renal failure after contrast-induced nephropathy is a clinically important and costly complication after the use of iodine-based contrast media. We investigated the cost and cost-effectiveness of 2 contrast media in patients at high risk of contrast-induced nephropathy. Methods: The analyses were based on a randomized, prospective, multinational clinical study comparing the nephrotoxic effects of an isosmolar nonionic contrast medium, iodixanol, with those of a low-osmolar nonionic contrast medium, iohexol. Resource utilization data were obtained from the study and from a retrospective review of patients' hospital records. Swedish, German, and French unit prices were applied to resources used. Between-group differences in average costs were analyzed using a nonparametric bootstrap method. Results: Resource utilization data for 125 patients were analyzed. Seven contrast media-related serious adverse reactions, of which 6 were acute renal failures, were noted in 6 patients receiving iohexol. Two patients in the iodixanol group had 1 nonserious reaction each. The mean hospitalization cost per patient was €489, €573, and €393 lower after iodixanol than after iohexol using Swedish, German, and French unit prices, respectively. The mean per-patient costs of treating adverse drug reactions were €371, €399, and €445 lower after iodixanol than after iohexol, using the respective unit prices (P = 0.01). Iodixanol was cost-effective compared with iohexol, with both lower costs and better effects related to fewer adverse drug reactions. Conclusions: The isosmolar contrast medium iodixanol appears to be cost-effective when compared with a low-osmolar contrast medium, iohexol, in diabetic patients with renal impairment undergoing angiography. © 2005, Elsevier Inc. All rights reserved.
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| 11. |
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| 12. |
- Aspelin, P, et al.
(författare)
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Nephrotoxic effects in high-risk patients undergoing angiography
- 2003
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 348:6, s. 491-499
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The use of iodinated contrast medium can result in nephropathy. Whether iso-osmolar contrast medium is less nephrotoxic than low-osmolar contrast medium in high-risk patients is uncertain. METHODS: We conducted a randomized, double-blind, prospective, multicenter study comparing the nephrotoxic effects of an iso-osmolar, dimeric, nonionic contrast medium, iodixanol, with those of a low-osmolar, nonionic, monomeric contrast medium, iohexol. The study involved 129 patients with diabetes with serum creatinine concentrations of 1.5 to 3.5 mg per deciliter who underwent coronary or aortofemoral angiography. The primary end point was the peak increase from base line in the creatinine concentration during the three days after angiography. Other end points were an increase in the creatinine concentration of 0.5 mg per deciliter or more, an increase of 1.0 mg per deciliter or more, and a change in the creatinine concentration from day 0 to day 7. RESULTS: The creatinine concentration increased significantly less in patients who received iodixanol. From day 0 to day 3, the mean peak increase in creatinine was 0.13 mg per deciliter in the iodixanol group and 0.55 mg per deciliter in the iohexol group (P=0.001, the increase with iodixanol minus the increase with iohexol, -0.42 mg per deciliter [95 percent confidence interval, -0.73 to -0.22]). Two of the 64 patients in the iodixanol group (3 percent) had an increase in the creatinine concentration of 0.5 mg per deciliter or more, as compared with 17 of the 65 patients in the iohexol group (26 percent) (P=0.002, odds ratio for such an increase in the iodixanol group, 0.09 [95 percent confidence interval, 0.02 to 0.41]). No patient receiving iodixanol had an increase of 1.0 mg per deciliter or more, but 10 patients in the iohexol group (15 percent) did. The mean change in the creatinine concentration from day 0 to day 7 was 0.07 mg per deciliter in the iodixanol group and 0.24 mg per deciliter in the iohexol group (P=0.003, value in the iodixanol group minus the value in the iohexol group, -0.17 mg per deciliter [95 percent confidence interval, -0.34 to -0.07]). CONCLUSIONS: Nephropathy induced by contrast medium may be less likely to develop in high-risk patients when iodixanol is used rather than a low-osmolar, nonionic contrast medium.
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| 13. |
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| 14. |
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| 15. |
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| 16. |
- Aspfors, Jessica, et al.
(författare)
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A metasynthesis of research on mentor education : three emerging dimensions
- 2015
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Konferensbidrag (refereegranskat)abstract
- The aim of this meta-synthesis is to deepen the understanding and knowledge of research focusing on education for mentors of newly qualified teachers (NQTs). Altogether, 10 studies met the criteria for full inclusion and were synthesised. Three overarching dimensions were found as a final synthesis guiding the further development of mentor education: 1) Contextual dimensions, 2) Theoretical-analytical dimensions, and 3) Relational dimensions. The synthesis stresses the importance of a systematic, long-term and research-based mentor education that develops mentors’ (self-)understanding of teaching and mentoring, i.e. is well integrated in the educational context, has a balance of theoretical and practical components, includes rich possibilities for interaction and reflection and prepares for an evidence-informed mentoring.A REVISED AND EXTENDED VERSION OF THIS PAPER HAS LATER BEEN PUBLISHED AS OPEN ACCESS, SEE: http://www.sciencedirect.com/science/article/pii/S0742051X1500030X
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| 17. |
- Aspfors, Jessica, et al.
(författare)
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Att kvalificera sig till mentor – perspektiv på kompetensbehov och utbildning av mentorer för nya lärare
- 2015
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Ingår i: Psykologi i kommunen. - 1892-3364. ; 50:2, s. 17-27
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Tidskriftsartikel (refereegranskat)abstract
- Under senare år har allt mer fokus och resurser riktats mot lärares kompetensutveckling. Ett område för satsningar har bl.a. varit mentorskap. Mycket har skrivits om mentorskap generellt och om nya lärare och deras behov speciellt, men vad vet vi om mentorers kompetensutveckling och lärande? Vilka kompetenser behövs och hur påverkar det utbildning av veiledere/mentorer? I denna artikel sätter vi fokus på kvalificering av mentorer för nya lärare och på den kompetens de kan behöva för att på ett medvetet och framgångsrikt sätt vara mentor för nya lärare. Vi kommer att diskuter vilka kompetenser mentorer kan behöva och hur det i sin tur kan påverka utbildning av veileder/mentorer – såväl till innehåll som till form. Vi kommer inte att gå närmare in på frågan i vilken mån mentorskap är positivt eller inte för nya lärare, eftersom vår bedömning är att det finns mycket forskning som på ett övertygande sätt visar på dess positiva effekter (se t.ex. Bjerkholt, 2012; Dahl et al., 2006; Ingersoll & Strong, 2011; Waterman & He, 2011), även om vissa frågetecken kan resas kring dess räckvidd, exempelvis för skolutveckling (Dahl et al., 2006). Vi tar utgångspunkt i den internationella forskningen på området men ger också konkreta exempel från ett nordiskt perspektiv, i synnerhet från Sverige och Finland. Vi inleder med en bakgrundsteckning kring vad tidigare forskning på området lyfter fram om mentorers professionella utveckling och lärande till att bli mentor.
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| 18. |
- Aspfors, Jessica, et al.
(författare)
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Collaboration or assessment? Some perspectives on mentoring in Finland and Sweden.
- 2010
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Ingår i: The conference Promoting Learning and Well-Being of Students and teacher at University of Jyväskylä, Finland, 7-9 June 2010..
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Konferensbidrag (refereegranskat)abstract
- Collaboration or assessment? Some perspectives on mentoring in Finland and Sweden JESSICA ASPFORS, Faculty of Education, Åbo Akademi University, Finland GÖRAN FRANSON, Faculty of Education and Business Studie, University of Gävle, Sweden HANNU L. T. HEIKKINEN, Finnish Institute for Educational Research, University of Jyväskylä, Finland In this presentation, some tensional trends within mentoring, which we call a contradiction between collaboration and assessment, will be addressed. The aim is threefold: firstly to describe and compare the development of mentoring programs in Finland and Sweden at a system level, secondly to illustrate how the various mentoring systems have been experienced by the persons involved and thirdly to discuss the political and ideological circumstances and the possible effects of these solutions. The study is based on empirical data from the Finnish and Swedish contexts, both on the level of mentors’ and NQTs’ experiences, based on interviews and/or focus group discussions and on the national policy level, based on policy documents on teacher education and, in the Swedish part, the responses of teacher educators to them. The tentative result indicates profound differences between the two national initiatives of mentoring in Finland and Sweden. The mentoring process in Finland, peer group mentoring, is clearly based on social constructivist assumptions on knowledge and learning. The integration of formal, informal and nonformal learning as well as the equality and professional autonomy as persons and professionals is central. The proposed system of a mandatory induction system in Sweden is, however, very different with mentoring, probation year, registration of teachers and possible assessment of NQTs as central components. In the presentation these issues will be discussed upon in terms of teachers’ continuing professional learning and development.
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| 19. |
- Aspfors, Jessica, et al.
(författare)
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Contested Architectures of Mentoring : Support, Supervision or Collective Self-Development
- 2013
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Konferensbidrag (refereegranskat)abstract
- In this paper, we describe contested practices of mentoring within and between Australia, Finland and Sweden. Our study is based on national policy documents and empirical data from participants involved in mentoring. The theoretical framework will build on practice theory (Kemmis & Grootenboer, 2008; Kemmis & Heikkinen 2012). The aim is to demonstrate three archetypes persisting in literature and practices: mentoring as supervision, support and collective self-development. In Australia, we find the three kinds of mentoring jostling with one another. In Finland, the perspective of collective self-development is emphasized. In Sweden, the traditional model of mentoring (support) has been typical since 1995, with a current reform of teacher induction which turns mentoring more into supervision.Our paper will show (1) that the meanings of 'mentoring' are contested within and between the countries involved; (2) that the three forms of mentoring identified represent three different projects: (a) assisting newly qualified teachers (NQTs) to pass through probation or (b) traditional mentoring of NQTs by more experienced teachers or (c) peer-group mentoring (PGM); and (3) that these three projects, that could be simultaneously present, also involve and imply quite different practice architectures in the form of different materialeconomic, social-political and cultural-discursive arrangements.
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| 20. |
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| 21. |
- Aspfors, Jessica, et al.
(författare)
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Mentoring as Dialogue, Collaboration and/or Assessment?
- 2012
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Ingår i: Transitions and Transformations in Learning and Education. - Dordrecht : Springer Berlin/Heidelberg. - 9789400723115 - 9789400723122 ; , s. 271-290
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Bokkapitel (refereegranskat)abstract
- In this chapter, some tensional trends within mentoring, which we call a contradiction between collaboration and assessment, are addressed. The aim is threefold: First, to describe and compare the development of mentoring programmes in Finland and Sweden at the system level; second, to illustrate how the various mentoring systems have been experienced by the persons involved; and third, to discuss the political and ideological circumstances and the possible effects of these solutions. The study is based on empirical data gathered in Finland and Sweden and examines the experiences of mentors and newly qualified teachers (NQTs) as well as the relevant national policies. The findings indicate profound differences between the two national initiatives of mentoring in Finland and Sweden. The mentoring process in Finland, using peer group mentoring, is based on social constructivistic assumptions regarding knowledge and learning. The integration of formal, informal and non-formal learning, as well as the equality and professional autonomy as a person and as a professional, is central. The system of mandatory induction in Sweden is very different, with mentoring, a probation year and the registration of teachers being central components. In such a system, the mentors' role of avoiding direct or indirect involvement in the assessment may become more challenging.
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| 22. |
- Aspfors, Jessica, et al.
(författare)
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Research on mentor education for mentors of newly qualified teachers : A qualitative meta-synthesis
- 2015
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Ingår i: Teaching and Teacher Education. - : Elsevier BV. - 0742-051X .- 1879-2480. ; 48, s. 75-86
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this meta-synthesis is to deepen the understanding and knowledge of qualitative research focusing on education for mentors of newly qualified teachers. Altogether, 10 studies were included and synthesised. Four common themes emerged in the initial analysis: School and mentoring context, Theory and practice, Reflection and critical thinking and Relationships. Furthermore, three overarching dimensions were found as a final synthesis guiding the further development of mentor education: 1) Contextual dimensions, 2) Theoretical-analytical dimensions, and 3) Relational dimensions. The synthesis stresses the importance of a systematic, long-term and research-informed mentor education that develops mentors' (self-)understanding of teaching and mentoring.
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| 23. |
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| 24. |
- Belfrage, Henrik, et al.
(författare)
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Management of violent behaviour in the correctional system using qualified risk assessments.
- 2004
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Ingår i: Legal and Criminological Psychology. - : Wiley-Blackwell. - 1355-3259 .- 2044-8333. ; 9:1, s. 11-22
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Tidskriftsartikel (refereegranskat)abstract
- Purpose. This study focused on whether institutional violence in a maximum-security correctional institution could be prevented using comprehensive risk assessments followed by adequate risk management. And, could this be shown by a decrease in risk factors for violence according to the HCR-20 Risk Assessment Scheme in the study group? Methods. Offenders with a history of violent criminality were subject to real-life assessments using the HCR-20 Risk Assessment Scheme. The assessments were followed by discussions with members of staff, in which risk management strategies were designed. Thus, the members of staff were fully aware of every inmate's personality characteristics (e.g. psychiatric diagnoses), what risk factors for violence they displayed, and how best to manage those risk factors. With the aim of evaluating the possible effects of our interventions, approximately one third of the study group was reassessed after a mean of 12 months. Results. The follow-up showed no significant decrease in important risk factors for violence in the study group. However, the number of violent incidents showed a remarkable decrease during the study period. Conclusions. Not being able to reduce important risk factors for violence does not necessarily mean that one cannot decrease the risk for, or the incidence of, violence. This study indicates that proper and adequate risk management, using the best protective factors available, can reduce violence even though important risk factors cannot be decreased. The study also supports the theoretical assumption that changes in risk factors are more possible in some populations (e.g. general psychiatric) than in others (e.g. correctional) depending on the nature of the study group and the risk factors that are at hand (e.g. dynamic vs. static). This seems to be important to bear in mind when performing evaluation research using risk assessment instruments.
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| 25. |
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| 26. |
- Belfrage, Henrik, et al.
(författare)
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Prediction of violence using the HCR-20 : a prospective study in two maximum-security correctional institutions
- 2000
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Ingår i: Journal of forensic psychiatry (Print). - : Routledge. - 0958-5184 .- 1469-9478. ; 11:1, s. 167-175
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Tidskriftsartikel (refereegranskat)abstract
- The HCR-20 and the PCL:SV were used in a prospective study of 41 long-term sentenced offenders in two correctional, maximum-security institutions. The aim was to test the validity of these instruments in the prediction of institutional violence. All assessments were made by a comprehensive examination of the offenders' files, completed with clinical interviews ranging from 1 to 3 hours. The mean follow-up time was 8 months. Our results show high predictive validity for the HCR-20's clinical and risk management items, but for almost none of its historical items. The results suggest that violence inside correctional institutions can be predicted with a certain degree of validity by using the HCR-20 and the PCL:SV, even within a selective 'high-risk' group of offenders such as that under study here.
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| 27. |
- Benson, Mikael, 1954, et al.
(författare)
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Altered levels of the soluble IL-1, IL-4 and TNF receptors, as well as the IL-1 receptor antagonist, in intermittent allergic rhinitis
- 2004
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Ingår i: Int Arch Allergy Immunol. - : S. Karger AG. - 1018-2438 .- 1423-0097. ; 134:3, s. 227-32
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The effects of cytokines are modulated by soluble cytokine receptors (SCR) and receptor antagonists. Therefore, allergic disease may depend on altered proportions between cytokines, their SCR and receptor antagonists, rather than absolute changes in cytokine levels. Little is known about SCR in intermittent allergic rhinitis (IAR). OBJECTIVE: To examine the concentrations of SCR, i.e. sIL-1R2, sIL-4R, sIL-6R and sTNFR1, as well as the interleukin-1 receptor antagonist (IL-1Ra) in nasal fluids from allergen-challenged patients with IAR and healthy controls. METHODS: 30 patients with birch- or grass-pollen-induced IAR and 30 healthy controls were studied. In the patients nasal fluids were obtained before as well as 1 and 6 h after allergen provocation. RESULTS: Both symptom scores and rhinoscopic signs of rhinitis increased in the patients after allergen challenge. Comparisons between patients and controls showed that sIL-4R was lower in patients before and 1 and 6 h after provocation. IL-1Ra was lower before and 1 h after provocation. In addition, lower concentrations of sTNFR1 were found in patients after 1 h, while sIL-1R2 concentrations were higher after 1 h. Comparisons of patients before and after challenge showed that IL-1Ra and sTNFR1 decreased after 1 h, while sIL-1R2 increased. No significant differences were found compared to 6 h. sIL-6R did not significantly differ between the study groups. CONCLUSIONS: After allergen challenge, significant changes in the nasal fluid levels of IL-1Ra, sIL-1R2 and sTNFR1 were found. By contrast, sIL-4R remained at lower levels than in controls both before and after challenge. Since sIL-4R modulates IgE synthesis, this may play a role in the pathogenesis of IAR.
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| 28. |
- Benyamine, Isak, 1963-
(författare)
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Bedömning som meningsskapande resurs i handledningssamtal : Multimodala och kvalitativa diskurser i konstnärlig högskoleutbildning
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this investigation is to describe assessment as a meaning-making process in individual supervision of students in higher education of the aesthetic field. The qualitative analyses focus on how assessment is expressed within the supervision, in relation to the artistic professional field. The study was conducted within a multimodal socio-semiotic perspective. Sadler’s notion of quality and Bourdieu’s field concept of habitus, contributes to the social practice within the professional field, and in the full analysis of the empirical material.The case study examines assessment in an authentic environment. The data consists of video recordings from ten supervisions that took place in two different courses at two different colleges. The video recordings were transcribed through a multimodal framework and focused on the teachers’ and student’s speech, body movements, gazes and gestures during the sessions. Four selected supervision sessions were analysed based on the research questions and on the theoretical framework.The analyses revealed that assessment in higher education of the aesthetic field can be expressed as a process whereby the quality is related to the professional field. The students, as well as their teachers, are immersed in relationships, traditions and institutions that shape their artistic choices and judgments.The results indicate that students' meaning-making is linked to their previous experience in the artistic field. Teachers’ expectations of this experience have crucial implications for how the supervision sessions are shaped and designed. The shift of focus in the supervisions goes from the fulfilment of goals stated in the curriculum, to the meaning making, values, and perspectives that are recognized within the field of the arts. The study underlines the importance of conceptualization of the artistic processes.The overall results confirm previous studies showing that instruction and supervision in higher education of the aesthetic field develops in relation to the teacher's authority, expertise and in relation to students' independence.
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| 29. |
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| 30. |
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| 31. |
- Bouchet, P., et al.
(författare)
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JWST MIRI Imager Observations of Supernova SN 1987A
- 2024
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 965:1
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Tidskriftsartikel (refereegranskat)abstract
- There exist very few mid-infrared (IR) observations of supernovae (SNe) in general. Therefore, SN 1987A, the closest visible SN in 400 yr, gives us the opportunity to explore the mid-IR properties of SNe, the dust in their ejecta, and the surrounding medium and to witness the birth of an SN remnant (SNR). The James Webb Space Telescope, with its high spatial resolution and extreme sensitivity, gives a new view on these issues. We report on the first imaging observations obtained with the Mid-InfraRed Instrument (MIRI). We build temperature maps and discuss the morphology of the nascent SNR. Our results show that the temperatures in the equatorial ring (ER) are quite nonuniform. This could be due to dust destruction in some parts of the ring, as had been assumed in some previous works. We show that the IR emission extends beyond the ER, illustrating the fact that the shock wave has now passed through this ring to affect the circumstellar medium on a larger scale. Finally, while submillimeter Atacama Large Millimeter Array observations have hinted at the location of the compact remnant of SN 1987A, we note that our MIRI data have found no such evidence.
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| 32. |
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| 33. |
- Dahl, Caroline, et al.
(författare)
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Ekosystemtjänsternas bidrag till god urban livsmiljö
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Ekosystemtjänster uppmärksammas alltmer som ett viktigt inslag för en hållbar utveckling av städer och samhällen. Dessa handlar inte bara om ett miljö- och biodiversitetsperspektiv, utan också om hur ekosystemen bidrar till människans livsmiljö och stadens attraktivitet, samt de praktiska och rekreativa nyttor som befintlig och anlagd natur kan skapa i den byggda miljön.Denna rapport har tillkommit på Naturvårdsverkets initiativ, vilka också delvis har finansierat den. Arbetet har sammanfallit med ett opinionsbildande projekt, projektlett av Tankesmedjan Movium ochfinansierat av Vinnova, kallat Påverkansplattform för urbana ekosystemtjänster. Båda dessa aktiviteterhar efterfrågat kartläggning av nuläget och redovisningar av lärande exempel, varför vi har valt att arbeta integrerat med aktiviteterna. I rapporten har vi försökt att kombinera generella reflektioner med konkreta exempel. Vi har också valt att hämta lärdomar från såväl praktik som akademi och har bjudit in några av de ledande forskarna från Sveriges lantbruksuniversitet att utifrån sin forskningshorisont kommentera sådant som vi tycker oss kunna konstatera i praktiken. Det kan i något fall bli motsägelsefullt, men så är också frågan kring ekosystemtjänster i urban miljö komplext beskaffad. Som alla komplext beskaffade frågor hyser den därmed inneboende målkonflikter, åtminstone på ett generellt och övergripande plan.I rapporten konstaterar vi att det är viktigt och grundläggande att ekosystemtjänster behandlas som en tillgång för livsmiljöer i staden, och därmed också för arbetet med att planera, gestalta, anlägga och förvalta dessa miljöer. Utgångspunkten för ett sådant arbete behöver vara platsernas förutsättningar och de förväntningar som vi har på dessa miljöer. Möjligen kan det uppfattas som lite motsägelsefullt för en rapport med namnet ”Ekosystemtjänsteras bidrag till en god urban livsmiljö”, men vi är övertygande om att utgångspunkten för arbetet med ekosystemtjänster bör inte vara ekosystemtjänsterna själva, snarare en ökad platsspecifik kunskap och en ökad tydlighet kring samhällets uttalade målsättningar. Varför inleder vi med ett sådant påstående? Jo, för att påminna om att ekosystemtjänsterna utgår från oss människor och tjänsterna svarar mot våra behov. Det är alltså en slags konsumtion av tjänster som vi pratar om och som i all hållbar konsumtion handlar det om att balansera mellan tillgång och efterfrågan. Vi menar alltså att det inte alltid handlar om att maximera uttaget av en viss ekosystemtjänst, utan det handlar snarare om vilket behov som vi har identifierat på en viss plats eller i ett visst sammanhang samt hur ekosystemtjänsterna kan levererar på den platsen utifrån identifierade behov. Det är måhända en hårfin perspektivförskjutning, men vi menar att tar vi inte med oss detta synsätt in i diskussionen om ekosystemtjänster så befarar vi att vi får ett oönskat överutnyttjande av naturens ”gratistjänster”.Det pågår mycket lovvärt arbete i landet för att hitta system och verktyg som strävar efter att finna helhetssyn och mångfunktionalitet i ekosystemtjänsterna. Det finns dock en risk att verktyg blir väl generella när man försöker att fånga upp alla aspekter av hur man kan arbeta med ekosystemtjänsterna. Då riskerar implementeringsglappen också att bli för stora när generella verktyg ska appliceras på en specifik plats. Att istället lära av hur andra har gjort och ta del av varandras erfarenheter kan då vara ett värdefullt komplement och Naturvårdsverket har därför bett Tankesmedjan Movium att ta fram denna exempelsamling. Vår förhoppning är att denna rapport ska hjälpa stadsbyggnadsprocessens olika aktörer och skeden att förstå nyttan med urban natur och att ta in ekosystemtjänsterna i befintliga arbetssätt och processer.
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| 34. |
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De första ljuva åren : lärares första tid i yrket
- 2001
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Samlingsverk (redaktörskap) (populärvet., debatt m.m.)abstract
- Kan den första tiden för nyblivna lärare utvecklas till att bli ett stöd i den professionella utvecklingen i stället för att vara en svår och omtumlande period? I denna antologi problematiseras lärarnas första tid som yrkesverksamma. Frågor som har att göra med deras utbildning, yrkessituation och professionella utveckling analyseras och diskuteras av nyblivna lärare, skolledare, fackliga organisationer och lärarutbildare. Nyutexaminerade pedagoger, verksamma i alltifrån förskolan till gymnasiet, beskriver sina erfarenheter från den första tiden i yrket. Till grund för diskussionen om att hitta former och innehåll som stödjer lärares professionella utveckling ligger en kritisk granskning av lärarutbildningarna, svensk och internationell forskning om den första tiden som lärare samt olika former och system för att stödja nya lärare. Boken vänder sig till lärare i slutskedet av sin grundläggande lärarutbildning, nyblivna lärare, mentorer, skolledare samt till lärarutbildare och forskare inom högskola och universitet.
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| 35. |
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| 36. |
- Eklund, Daniel, 1984-, et al.
(författare)
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Vitamin D enhances IL-1β secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients
- 2013
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Ingår i: International journal of mycobacteriology. - Netherlands : Wolters Kluwer. - 2212-5531. ; 2:1, s. 18-25
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Tidskriftsartikel (refereegranskat)abstract
- The emergence of multidrug-resistant strains of Mycobacterium tuberculosis (MTB), the bacterium responsible for tuberculosis (TB), has rekindled the interest in the role of nutritional supplementation of micronutrients, such as vitamin D, as adjuvant treatment. Here, the growth of virulent MTB in macrophages obtained from the peripheral blood of patients with and without TB was studied. The H37Rv strain genetically modified to express Vibrio harveyi luciferase was used to determine the growth of MTB by luminometry in the human monocyte-derived macrophages (hMDMs) from study subjects. Determination of cytokine levels in culture supernatants was performed using a flow cytometry-based bead array technique. No differences in intracellular growth of MTB were observed between the different study groups. However, stimulation with 100nM 1,25-dihydroxyvitamin D significantly enhanced the capacity of hMDMs isolated from TB patients to control the infection. This effect was not observed in hMDMs from the other groups. The interleukin (IL)-1β and IL-10 release by hMDMs was clearly increased upon stimulation with 1,25-dihydroxyvitamin D. Furthermore, the 1,25-dihydroxyvitamin D stimulation also led to elevated levels of TNF-α (tumor necrosis factor-alpha) and IL-12p40. It was concluded that vitamin D triggers an inflammatory response in human macrophages with enhanced secretion of cytokines, as well as enhancing the capacity of hMDMs from patients with active TB to restrict mycobacterial growth.
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| 37. |
- Eriksson, Eva Wiman, et al.
(författare)
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A prospective 10-year follow-up polygraphic study of patients treated with a mandibular protruding device
- 2015
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Ingår i: Sleep and Breathing. - : Springer Science and Business Media LLC. - 1520-9512 .- 1522-1709. ; 19:1, s. 393-401
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Tidskriftsartikel (refereegranskat)abstract
- This 10-year follow-up prospective study aimed to evaluate the effects of treatment with a mandibular protruding device (MPD) on respiratory parameters and subjective symptoms in patients with obstructive sleep apnea (OSA) or snoring. Seventy-seven consecutive patients diagnosed with OSA or snoring were treated with an MPD. At baseline and the 10-year follow-up, a polygraphic examination and questionnaires on sleep quality were administrated and weight, and neck size was measured. At the 10-year follow-up, we examined 64 of the 77 patients and recorded their current treatment (45 MPD, 9 continuous positive airway pressure (CPAP), and 10 no treatment). For MPD patients, 89 % reported MPD use every night and 9 % several nights a week. Compared to baseline, MPD users with OSA had a significantly decreased oxygen desaturation index (ODI) (p = 0.006) and increased lowest arterial oxygen saturation, SaO(2) nadir (p = 0.007) after 10 years. MPD treatment was successful for 70 % of OSA patients, yet 89 % subjectively considered themselves cured, indicating overestimation of the treatment effect. OSA patients who responded to treatment maintained baseline weight and neck size, while these increased for non-responders. Of the baseline snorers still using an MPD, 93 % maintained an ODI value of < 5. All CPAP users had an ODI value of < 5. Both OSA and snorers using an MPD had significantly fewer self- and relative reports of snoring, apnea, daytime tiredness, and poor night sleep quality (p < 0.001). MPD treatment is well tolerated and effective in a long-term, 10-year perspective. Weight gain may jeopardize MPD effects. Both patients and relatives reported significantly less snoring and fewer periods of apnea.
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| 38. |
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| 39. |
- Fransson, Anette E, et al.
(författare)
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Hydrogen Inhalation Protects against Ototoxicity Induced by Intravenous Cisplatin in the Guinea Pig
- 2017
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Ingår i: Frontiers in Cellular Neuroscience. - : Frontiers Media SA. - 1662-5102. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Permanent hearing loss and tinnitus as side-effects from treatment with the anticancer drug cisplatin is a clinical problem. Ototoxicity may be reduced by co-administration of an otoprotective agent, but the results in humans have so far been modest.Aim: The present preclinical in vivo study aimed to explore the protective efficacy of hydrogen (H2) inhalation on ototoxicity induced by intravenous cisplatin.Materials and Methods: Albino guinea pigs were divided into four groups. The Cispt (n = 11) and Cispt+H2 (n = 11) groups were given intravenous cisplatin (8 mg/kg b.w., injection rate 0.2 ml/min). Immediately after, the Cispt+H2 group also received gaseous H2 (2% in air, 60 min). The H2 group (n = 5) received only H2 and the Control group (n = 7) received neither cisplatin nor H2. Ototoxicity was assessed by measuring frequency specific ABR thresholds before and 96 h after treatment, loss of inner (IHCs) and outer (OHCs) hair cells, and by performing densitometry-based immunohistochemistry analysis of cochlear synaptophysin, organic transporter 2 (OCT2), and copper transporter 1 (CTR1) at 12 and 7 mm from the round window. By utilizing metabolomics analysis of perilymph the change of metabolites in the perilymph was assessed.Results: Cisplatin induced electrophysiological threshold shifts, hair cell loss, and reduced synaptophysin immunoreactivity in the synapse area around the IHCs and OHCs. H2 inhalation mitigated all these effects. Cisplatin also reduced the OCT2 intensity in the inner and outer pillar cells and in the stria vascularis as well as the CTR1 intensity in the synapse area around the IHCs, the Deiters' cells, and the stria vascularis. H2 prevented the majority of these effects.Conclusion: H2 inhalation can reduce cisplatin-induced ototoxicity on functional, cellular, and subcellular levels. It is proposed that synaptopathy may serve as a marker for cisplatin ototoxicity. The effect of H2 on the antineoplastic activity of cisplatin needs to be further explored.
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| 40. |
- Fransson, Anette Elisabeth, et al.
(författare)
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Inhalation of Molecular Hydrogen, a Rescue Treatment for Noise-Induced Hearing Loss
- 2021
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Ingår i: Frontiers in Cellular Neuroscience. - : Frontiers Media S.A.. - 1662-5102. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- Noise exposure is the most important external factor causing acquired hearing loss in humans, and it is strongly associated with the production of reactive oxygen species (ROS) in the cochlea. Several studies reported that the administration of various compounds with antioxidant effects can treat oxidative stress-induced hearing loss. However, traditional systemic drug administration to the human inner ear is problematic and has not been successful in a clinical setting. Thus, there is an urgent need to develop rescue treatment for patients with acute acoustic injuries. Hydrogen gas has antioxidant effects, rapid distribution, and distributes systemically after inhalation.The purpose of this study was to determine the protective efficacy of a single dose of molecular hydrogen (H-2) on cochlear structures. Guinea pigs were divided into six groups and sacrificed immediately after or at 1 or 2 weeks. The animals were exposed to broadband noise for 2 h directly followed by 1-h inhalation of 2% H-2 or room air. Electrophysiological hearing thresholds using frequency-specific auditory brainstem response (ABR) were measured prior to noise exposure and before sacrifice. ABR thresholds were significantly lower in H-2-treated animals at 2 weeks after exposure, with significant preservation of outer hair cells in the entire cochlea. Quantification of synaptophysin immunoreactivity revealed that H-2 inhalation protected the cochlear inner hair cell synaptic structures containing synaptophysin. The inflammatory response was greater in the stria vascularis, showing increased Iba1 due to H-2 inhalation.Repeated administration of H-2 inhalation may further improve the therapeutic effect. This animal model does not reproduce conditions in humans, highlighting the need for additional real-life studies in humans.
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| 41. |
- Fransson, Anette M. C., 1954-, et al.
(författare)
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A prospective 10-year cephalometric follow-up study of patients with obstructive sleep apnea and snoring who used a mandibular protruding device
- 2020
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Ingår i: American Journal of Orthodontics and Dentofacial Orthopedics. - : Elsevier. - 0889-5406 .- 1097-6752. ; 157:1, s. 91-97
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: This 10-year prospective cephalometric study evaluates the influence of a mandibular protruding device (MPD) in people with obstructive sleep apnea and snoring.Methods: A baseline study population of 77 people was followed biennially. After 10 years, 65 people (45 MPD users and 20 stopped-MPD users) were reexamined. At baseline and after 10 years, a lateral cephalogram was taken in the upright position.Results: MPD users showed significant changes in all cephalometric variables except for maxillary protrusion. The maxillary incisors were retroclined by a mean -4.2 degrees (standard deviation [SD] 3.95; P <0.001), mandibular incisors were proclined by a mean 3.2 degrees (SD, 5.02; P <0.001), and SNB was reduced by a mean -0.6 degrees (SD 1.41; P = 0.01). In those who had stopped MPD use, these initial cephalometric values were retained. Significant changes in decreased overjet and overbite were seen in the MPD group but not in the MPD-stopped group. The length of the mandible (Cd-Pg) increased by a mean of 5.1 mm (SD 6.78; P <0.001) and 6.1 mm (SD 5.99; P <0.001) in MPD and MPD-stopped groups, respectively. The hyoid bone-mandibular plane distance (hy-ML) increased by a mean of 3.3 mm (SD, 2.90; P <0.001) and 3.8 mm (SD 3.67; P = 0.001) in MPD and MPD-stopped groups, respectively.Conclusions: Long-term nocturnal MPD use causes retroclination of the maxillary incisors and proclination of the mandibular incisors with consequent decreased overjet and overbite. Both MPD and MPD-stopped users obtained increased mandibular length and lower position of the hyoid bone, which can be a normal physiological change with age.
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| 42. |
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| 43. |
- Fransson, Anette M. C., 1954-, et al.
(författare)
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Gender differences in oral appliance treatment of obstructive sleep apnea
- 2024
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Ingår i: Sleep and Breathing. - : Springer. - 1520-9512 .- 1522-1709. ; 28:4, s. 1723-1730
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Although overall success rates for treating obstructive sleep apnea (OSA) with an oral appliance (OA) are high, they are significantly higher among females. To verify published data, the study's purpose was to evaluate a participant sample after one year of OA use. The primary outcome was treatment response, with responders defined as having an apnea-hypopnea index (AHI) < 10 at follow-up and/or reduced by ≥50% of baseline. Secondary measures were from standardized questionnaires.METHODS: A sample of 314 participants, predominately with moderate-to-severe OSA, were enrolled and instructed to use an OA every night. At baseline and one-year follow-up, polygraphic recordings and questionnaires, including sleepiness (measured using the Epworth sleepiness scale) and quality-of-life (measured using the Functional Outcomes of Sleep Questionnaire), were collected.RESULTS: Among the 314 participants, 192 completed the one-year evaluation: 51 females (27%) and 141 males (73%). Overall, OA treatment resulted in 78% and 77% responders among females and males, respectively. Neither the difference in improvement nor the absolute change in AHI differed significantly based on gender, at any OSA severity level. There were no significant gender differences in sleepiness or quality of life. Treatment-related adverse reactions were more common among females.CONCLUSION: Both females and males with OSA respond well to OA therapy, with nonsignificant gender differences in outcomes. Thus, the hypothesis that females respond better to OA treatment is rejected.
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| 44. |
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| 45. |
- Fransson, Anette M. C., 1954-, et al.
(författare)
-
The outcome of oral appliance therapy on position-dependent obstructive sleep apnea : A multicenter randomized controlled trial
- 2022
-
Ingår i: American Journal of Orthodontics and Dentofacial Orthopedics. - : Elsevier. - 0889-5406 .- 1097-6752. ; 162:3, s. 386-393
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: This multicenter trial on patients with obstructive sleep apnea (OSA) treated with an oral appliance aimed to determine the effect of sleeping positions.METHODS: A cohort of 314 patients with OSA were enrolled and evaluated at 8 weeks and 1 year, focusing on treatment effects. At baseline and the 2 follow-ups, new polygraphic registration comparing the proportion of treatment responders without position-dependent OSA (non-position-dependent OSA [non-POSA]) and with POSA was used.RESULTS: At the 8-week and 1-year follow-up, 205 and 139 patients were included, respectively. The proportion of responders (apnea-hypopnea index [AHI] <10 and/or ≥50% reduction in AHI) was 56% for the non-POSA group and 69% for the POSA group (not significant [NS]). The responders increased at the 1-year follow-up: 68% and 77% for the non-POSA and POSA groups (NS), respectively. The absolute change in AHI in all sleeping positions at 8 weeks was -12.9 (interquartile range, -25.0 to -0.5) in the non-POSA group and -10.5 (interquartile range, -19.9 to -5.3; NS) in the POSA group. However, the decrease in supine AHI was significantly greater among subjects with POSA. In contrast, the decrease in nonsupine AHI was significantly greater in the non-POSA group, an effect that remained at the 1-year follow-up.CONCLUSIONS: Our hypothesis that subjects with POSA at baseline would have a higher treatment response rate after oral appliance treatment compared with subjects without POSA was rejected. However, those with POSA had a significantly higher supine AHI decrease, and those without POSA had significantly less nonsupine AHI.
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| 46. |
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| 47. |
- Fransson, Claes, 1951-, et al.
(författare)
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Emission lines due to ionizing radiation from a compact object in the remnant of Supernova 1987A
- 2024
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 383:6685, s. 898-903
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Tidskriftsartikel (refereegranskat)abstract
- The nearby Supernova 1987A was accompanied by a burst of neutrino emission, which indicates that a compact object (a neutron star or black hole) was formed in the explosion. There has been no direct observation of this compact object. In this work, we observe the supernova remnant with JWST spectroscopy, finding narrow infrared emission lines of argon and sulfur. The line emission is spatially unresolved and blueshifted in velocity relative to the supernova rest frame. We interpret the lines as gas illuminated by a source of ionizing photons located close to the center of the expanding ejecta. Photoionization models show that the line ratios are consistent with ionization by a cooling neutron star or a pulsar wind nebula. The velocity shift could be evidence for a neutron star natal kick.
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| 48. |
- Fransson, Erik, 1990, et al.
(författare)
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Complexions and grain growth retardation: First-principles modeling of phase boundaries in WC-Co cemented carbides at elevated temperatures
- 2021
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Ingår i: Acta Materialia. - : Elsevier BV. - 1359-6454. ; 216
-
Tidskriftsartikel (refereegranskat)abstract
- WC-Co cemented carbides combine superb hardness with high toughness making them ideal for usage in metal machining and in wear resistant tools. Controlling the WC grain size is important during sintering as grain size plays a crucial role for the mechanical properties of the material. Experimental studies have observed different growth rates and grain morphologies in W-rich and C-rich materials, but the mechanism behind this has not been clarified. Here, we consider the possibility of an interface-stabilized state, a complexion, at the WC/Co phase boundary in cemented carbides, namely thin WC films with cubic structure. An interfacial phase diagram is derived using ab-initio calculations and first-principles modeling. Cluster expansions are employed to model carbon vacancies and Monte Carlo simulations to sample the configurational entropy. Force-constant fitting is used to extract the harmonic free energy for ground-state structures and the effects from anharmonicity and electronic excitations are effectively incorporated from a companion study on WC bulk phases. We predict the stabilization of thin cubic WC films at liquid phase sintering temperatures but only at W-rich conditions. This is consistent with experimental findings where thin films with cubic stacking have been observed predominantly in W-rich materials. We use this knowledge to suggest an explanation for the observed different growth rates and grain morphologies in W-rich and C-rich cemented carbides.
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| 49. |
- Fransson, Erik, 1990, et al.
(författare)
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Dynasor - A Tool for Extracting Dynamical Structure Factors and Current Correlation Functions from Molecular Dynamics Simulations
- 2021
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Ingår i: Advanced Theory and Simulations. - : Wiley. - 2513-0390. ; 4:2
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Tidskriftsartikel (refereegranskat)abstract
- Perturbative treatments of the lattice dynamics are widely successful for many crystalline materials; however, their applicability is limited for strongly anharmonic systems, metastable crystal structures and liquids. The full dynamics of these systems can, however, be accessed via molecular dynamics (MD) simulations using correlation functions, which includes dynamical structure factors providing a direct bridge to experiment. To simplify the analysis of correlation functions, here the dynasor package is presented as a flexible and efficient tool that enables the calculation of static and dynamical structure factors, current correlation functions as well as their partial counterparts from MD trajectories. The dynasor code can handle input from several major open source MD packages and thanks to its C/Python structure can be readily extended to support additional codes. The utility of dynasor is demonstrated via examples for both solid and liquid single and multi-component systems. In particular, the possibility to extract the full temperature dependence of phonon frequencies and lifetimes is emphasized.
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| 50. |
- Fransson, Erik, 1990, et al.
(författare)
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First-principles modeling of complexions at the phase boundaries in Ti-doped WC-Co cemented carbides at finite temperatures
- 2021
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Ingår i: Physical Review Materials. - : American Physical Society (APS). - 2475-9953. ; 5:9
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Tidskriftsartikel (refereegranskat)abstract
- WC-Co cemented carbides have a unique combination of high hardness and good toughness, making them ideal as tool materials in applications such as metal machining or rock drilling. Dopants are commonly added to retard grain growth and thereby creating a harder material. Thin films with cubic structure have been observed experimentally at phase boundaries between hexagonal WC and fcc Co-rich binder when doping with, e.g., Ti, V, or Cr. These films are generally considered to play a crucial role in the grain growth inhibition effect. Therefore, the thermodynamics of these thin cubic films is important to understand. Here, we construct, using ab initio calculations and modeling, an interfacial phase diagram for thin cubic films in Ti-doped WC-Co. We consider C <-> vacancy and W <-> Ti substitutions by constructing alloy cluster expansions and use Monte Carlo simulations to calculate the configurational free energy. Furthermore, force-constant fitting is used to extract the harmonic free energy for the ground-state structures. Additionally, we use information from thermodynamic databases to couple our atomic-scale calculations to overall compositions of typical WC-Comaterials. We predict that Ti segregates to WC/Co phase boundaries to form thin cubic films of two metallic layer thickness, both at solid-state and liquid-phase sintering temperatures. Furthermore, we predict that these films are stable also for low doping concentrations when no Ti-containing carbide phase precipitates in the material. We show that Ti essentially only segregates to the inner layer of the thin cubic film leaving an almost pure W layer towards Co, an ordering which has been observed in recent experimental high-resolution transmission electron microscopy studies.
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