| 1. |
- Klintström, Benjamin, et al.
(författare)
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Feature space clustering for trabecular bone segmentation
- 2017
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Ingår i: 20th Scandinavian Conference on Image Analysis, SCIA 2017. - Cham : Springer. - 9783319591285 - 9783319591292 ; , s. 65-75
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Konferensbidrag (refereegranskat)abstract
- Trabecular bone structure has been shown to impact bone strength and fracture risk. In vitro, this structure can be measured by micro-computed tomography (micro-CT). For clinical use, it would be valuable if multi-slice computed tomography (MSCT) could be used to analyse trabecular bone structure. One important step in the analysis is image volume segmentation. Previous segmentation techniques have either been computer resource intensive or produced sub-optimal results when used on MSCT data. This paper proposes a new segmentation method that tries to balance good results against computational complexity. Material. Fourteen human radius specimens where scanned with MSCT and segmented using the proposed method as well as two segmentation methods previously used to segment trabecular bone (Otsu and Automated Region Growing (ARG)). The proposed method (named FCH) uses a combination of feature space clustering, edge detection and hysteresis thresholding. For evaluation, we computed correlations with the reference method micro-CT for 7 structure parameters and measured segmentation time. Results. Correlations with micro-CT were highest for FCH in 3 cases, highest for ARG in 3 cases, and in general lower for Otsu. Both FCH and ARG had correlations higher than 0.80 for all parameters, except for trabecular thickness and trabecular termini. FCH was 60 times slower than Otsu, but 5 times faster than ARG. Discussion. The high correlations with micro-CT suggest that with a suitable segmentation method it might be possible to analyse trabecular bone structure using MSCT-machines. The proposed segmentation method may represent a useful balance between speed and accuracy.
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| 2. |
- Forouzan, Farnoosh, et al.
(författare)
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Artificial neural network models for production of nano-grained structure in AISI 304L stainless steel by predicting thermo-mechanical parameters
- 2009
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Ingår i: International Journal of Iron & Steel Society. ; 6:2, s. 6-13
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Tidskriftsartikel (refereegranskat)abstract
- An artificial neural network (ANN) model is developed for the analysis, simulation, and prediction of the austenite reversion in the thermo-mechanical treatment of 304L austenitic stainless steel. The results of the ANN model are in good agreement with the experimental data. The model is used to predict an appropriate annealing condition for austenite reversion through the martensite to austenite transformation. This model can also be used as a guide for further grain refining and to improve mechanical properties of the AISI 304L stainless steel.
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| 3. |
- Yildiz, H. Emre, et al.
(författare)
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- 2016
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Ingår i: Journal of International Business Studies. - : Springer Science and Business Media LLC. - 0047-2506 .- 1478-6990. ; 47:7, s. 830-857
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Tidskriftsartikel (refereegranskat)abstract
- The concept of psychic distance has several entrenched assumptions that have not been put to sufficient systematic scrutiny. We address this gap by investigating the assumptions of symmetry (i.e., whether psychic distance from Country A to Country B is the same as that from Country B to Country A) and discordance (i.e., whether differences in psychic distance between two countries always lead to lack of fit) of psychic distance in cross-border mergers and acquisitions. We propose a new framework, which differentiates between the extent (i.e., the degree to which two countries are perceived to be similar/different) and effects (i.e., the degree to which distance perceptions create favorable or unfavorable attitudes and responses) of psychic distance perceptions. We argue that relative status positions affect extent and effects of psychic distance. To test our predictions, we collected data through policy-capturing studies in Sweden and China. Our findings reveal that both the extent and the effects of psychic distance perceptions are asymmetric. We also found that psychic distance perceptions create unfavorable (favorable) attitudes among Swedish (Chinese) respondents toward Chinese (Swedish) acquirers. Our follow-up examination confirms that relative status positions are a key driver of these results.
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| 4. |
- Arndt, Anton, 1968-, et al.
(författare)
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Non-uniform displacement within the Achilles tendon durig passive ankle joint motion.
- 2012
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Ingår i: Knee Surgery, Sports Traumatology, Arthroscopy. - : Springer Science and Business Media LLC. - 0942-2056 .- 1433-7347. ; 20:9, s. 1868-74
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE:An initial step in the understanding of Achilles tendon dynamics is to investigate the effects of passive motion, thereby minimising muscle activation and reducing internal joint forces. Internal tendon dynamics during passive ankle joint motion have direct implications for clinical rehabilitation protocols after Achilles tendon surgery. The aim of this study was to test the hypothesis that tendon tissue displacement is different in different layers of the Achilles tendon during controlled passive ankle joint movements.METHODS:Ultrasound imaging was conducted on the right Achilles tendon of nine healthy recreationally active males. Standardised isokinetic passive dorsi-plantar-flexion movements were performed with a total range of motion of 35°. The tendon was divided into superficial, central and deep layers in the resulting B-mode ultrasound images viewed in the sagittal plane. A block-matching speckle tracking algorithm was applied post-process, with kernels for the measurement of displacement placed in each of the layers.RESULTS:The mean (SD) displacement of the Achilles tendon during passive dorsiflexion was 8.4 (1.9) mm in the superficial layer, 9.4 (1.9) mm in the central portion and 10.4 (2.1) mm in the deep layer, respectively. In all cases, the movement of the deep layer of the tendon was greater than that of the superficial one (P < 0.01).CONCLUSIONS:These results, achieved in vivo with ultrasonographic speckle tracking, indicated complex dynamic differences in different layers of the Achilles tendon, which could have implications for the understanding of healing processes of tendon pathologies and also of normal tendon function.
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| 5. |
- Nagel, Johanna, et al.
(författare)
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Treatment with belimumab in systemic lupus erythematosus does not impair antibody response to 13-valent pneumococcal conjugate vaccine.
- 2017
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Ingår i: Lupus. - : SAGE Publications. - 0961-2033 .- 1477-0962. ; 26:10, s. 1072-1081
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Tidskriftsartikel (refereegranskat)abstract
- Background/purpose: The objective of this study was to explore the impact of systemic lupuserythematosus and belimumab given in addition to standard of care therapy on 13-valentconjugated pneumococcal vaccine (PCV13) response. Methods: Forty-seven systemic lupuserythematosus patients and 21 healthy controls were immunized with a single dose of13-valent conjugated pneumococcal vaccine. Forty systemic lupus erythematosus patientswere treated with traditional disease-modifying anti rheumatic drugs, 11 of those receivedbelimumab in addition, and 32 patients were treated with concomitant prednisolone.Quantification of serotype specific IgG levels to 12 pneumococcal capsular polysaccharideswas performed in serum taken before and four to six weeks after vaccination using multiplexfluorescent microsphere immunoassay. IgG levels against serotypes 23F and 6B were alsoanalyzed using standard enzyme-linked immunosorbent assays. Opsonophagocyticassay was performed on serotype 23F to evaluate the functionality of the antibodies. Preandpost-vaccination log transformed antibody levels were compared to determine theimpact of systemic lupus erythematosus diagnosis and different treatments on antibodyresponse. Results: Systemic lupus erythematosus patients as a group showed lower postvaccinationantibody levels and lower fold increase of antibody levels after vaccinationcompared to controls (p¼0.02 and p¼0.009, respectively). Systemic lupus erythematosuspatients treated with belimumab in addition to standard of care therapy or with only hydroxychloroquinedid not differ compared to controls, whereas the other treatment groups hadsignificantly lower fold increase of post-vaccination antibody levels. Higher age was associatedwith lower post-vaccination antibody levels among systemic lupus erythematosuspatients. Conclusion: Belimumab given in addition to traditional disease-modifyinganti rheumatic drugs or prednisolone did not further impair antibody response to 13-valentconjugated pneumococcal vaccine.
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| 6. |
- Voronova, Liudmila, 1987-
(författare)
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Crisis and journalism culture transformation: The case of Ukraine
- 2017
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Ingår i: Nordmedia conference 2017.
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Konferensbidrag (refereegranskat)abstract
- Journalism culture is described by scholars as “one of the resources journalists draw upon to coordinate their activities as reporters, photographers, and editors” (Zelizer 2005, p. 204). Importantly, journalism cultures should be analyzed not only in connection to the contexts, but also in and as processes (Voronova 2014, p. 221). While most journalism cultures in the world face similar challenges, such as commercialization and digitalization, some of them are challenged by more radical challenges, such as war conflicts. Ukrainian journalism culture since 2013 is undergoing a painful process of continuously adjusting to and counteracting the circumstances of conflict, with external and internal propaganda (e.g. coming from the so-called “people’s republics” of Donetsk and Luhansk), economic pressure being a consequence of the more general crisis, and guidelines coming from the state institutions, such as the Ministry of Information Policy (MIP) (e.g. Bolin, Jordan & Ståhlberg 2016, Pantti 2016, Nygren & Hök 2016). Nygren et al. (2016), based on content analysis and interviews with journalists, conclude that one of the main challenges for the Ukrainian journalists today is a conflict between the ideal of neutrality in coverage and favoring of “patriotic journalism” in practice. This paper takes this discussion further and suggests to look at how the professional journalism organizations in Ukraine reflect upon this conflict, which journalists themselves define as a split between journalists and “Glory-to-Ukraine-journalists” (Sklyarevskaya 2016, October 20th). How does the participation of Ukrainian journalism organizations in the discussion of objectivity vs. patriotism look like on different levels – international, regional, national and local? Is there a possibility to retain a national culture of journalism in the situation of crisis, or does it inevitably end up in splitting to many journalism cultures that have their own rules, beliefs and ideals? Using Hanitzsch’s model of deconstruction of journalism culture (Hanitzsch 2007, Nygren et al 2016), and focusing specifically on the dimension of epistemological beliefs, this paper analyzes a specific case: project ”Two countries – one profession” initiated and supported by the OSCE Representative on Freedom of the Media. The project consists of regular round tables where senior representatives from Ukrainian and Russian professional journalism organizations meet to discuss ways to improve professional standards and safety of journalists, as well as collaborative projects between young journalists from the two countries. The project is perceived as contradictory and provocative by a part of the Ukrainian media community (e.g. Rudenko 2016, December 15th). The paper is based on analysis of observations of meetings between the National Union of Journalists of Ukraine and the Russian Union of Journalists, interviews with representatives of these and other media organizations and experts in Ukraine, focus groups with the young journalists involved in the project, and negative and positive reactions to this project by the Ukrainian media community.
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| 7. |
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| 8. |
- Hamdan, Sadeque, et al.
(författare)
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On the binary formulation of air traffic flow management problems
- 2023
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Ingår i: Annals of Operations Research. - : Springer. - 0254-5330 .- 1572-9338. ; 321, s. 267-279
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Tidskriftsartikel (refereegranskat)abstract
- We discuss a widely used air traffic flow management formulation. We show that this formulation can lead to a solution where air delays are assigned to flights during their take-off which is prohibited in practice. Although air delay is more expensive than ground delay, the model may assign air delay to a few flights during their take-off to save more on not having as much ground delay. We present a modified formulation and verify its functionality in avoiding incorrect solutions.
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| 9. |
- Kegelaers, Jolan, et al.
(författare)
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Promoting mental health in esports
- 2024
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Ingår i: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- There is growing recognition of the demands and health challenges experienced by esports athletes. The purpose of this perspective paper is to draw specific attention to the mental health of competitive gamers and spur on both future research and applied initiatives focussing on this important but under-addressed topic. We will briefly discuss the prevalence of mental health concerns, domain-specific stressors, and the need for comprehensive mental health support systems tailored to the esports context. It is our hope that, with this perspective paper, we can help set a new research agenda addressing mental health in esports.
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| 10. |
- Ademuyiwa, Adesoji O., et al.
(författare)
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Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries
- 2016
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Ingår i: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 1:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally.Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression.Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed.Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas.
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