| 1. |
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| 2. |
- Andersson, Agneta, et al.
(författare)
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Domiciliary liquid oxygen versus concentrator treatment in chronic hypoxaemia: a cost-utility analysis
- 1998
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Ingår i: European Respiratory Journal. - 1399-3003. ; 12:6, s. 1284-1289
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Tidskriftsartikel (refereegranskat)abstract
- Whether long-term oxygen therapy (LTOT) improves quality of life in chronic hypoxaemia has been questioned. LTOT with an oxygen concentrator (C/C) and gas cylinders for ambulation is considered cumbersome compared to mobile liquid oxygen equipment (L). The hypothesis for this study was that LTOT with liquid oxygen treatment (L) improves patients' health-related quality of life, but that it is also more expensive compared to concentrator (C/C) treatment. A prospective, randomized multicentre trial comparing C/C with L for LTOT was conducted during a six-month period. Fifty-one patients (29 on L and 22 on C/C) with chronic hypoxaemia, regularly active outside the home, participated in the study initially. Costs for oxygen were obtained from the pharmacies. Patient diaries and telephone contacts with members of the healthcare sector were used to estimate costs. Health-related quality of life was measured by the Sickness Impact Profile (SIP) and the EuroQol, instruments at the start and after 6 months. The average total cost per patient for group C/C for the six-month period was US$1,310, and for group L it was US$4,950. Health-related quality of life measured by the SIP instrument showed significant differences in favour of group L in the categories/dimensions of physical function, body care, ambulation, social interaction and total SIP score. In conclusion, liquid-oxygen treatment was more expensive compared to concentrator treatment. However, treatment effects showed that liquid oxygen had a better impact on quality of life.
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| 3. |
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| 4. |
- Bonfiglio, F., et al.
(författare)
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Female-Specific Association Between Variants on Chromosome 9 and Self-Reported Diagnosis of Irritable Bowel Syndrome
- 2018
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Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 155:1, s. 168-179
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: Genetic factors are believed to affect risk for irritable bowel syndrome (IBS), but there have been no sufficiently powered and adequately sized studies. To identify DNA variants associated with IBS risk, we performed a genome-wide association study (GWAS) of the large UK Biobank population-based cohort, which includes genotype and health data from 500,000 participants. METHODS: We studied 7,287,191 high-quality single nucleotide polymorphisms in individuals who self-reported a doctor's diagnosis of IBS (cases; n = 9576) compared to the remainder of the cohort (controls; n = 336,499) (mean age of study subjects, 40-69 years). Genome-wide significant findings were further investigated in 2045 patients with IBS from tertiary centers and 7955 population controls from Europe and the United States, and a small general population sample from Sweden (n = 249). Functional annotation of GWAS results was carried out by integrating data from multiple biorepositories to obtain biological insights from the observed associations. RESULTS: We identified a genome-wide significant association on chromosome 9q31.2 (single nucleotide polymorphism rs10512344; P = 3.57 x 10(-8)) in a region previously linked to age at menarche, and 13 additional loci of suggestive significance (P < 5.0 x 10(-6)). Sex-stratified analyses revealed that the variants at 9q31.2 affect risk of IBS in women only (P = 4.29 x 10(-10) in UK Biobank) and also associate with constipation-predominant IBS in women (P = .015 in the tertiary cohort) and harder stools in women (P = .0012 in the population-based sample). Functional annotation of the 9q31.2 locus identified 8 candidate genes, including the elongator complex protein 1 gene (ELP1 or IKB-KAP), which is mutated in patients with familial dysautonomia. CONCLUSIONS: In a sufficiently powered GWAS of IBS, we associated variants at the locus 9q31.2 with risk of IBS in women. This observation may provide additional rationale for investigating the role of sex hormones and autonomic dysfunction in IBS.
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| 5. |
- Czarniawska, Barbara, 1948, et al.
(författare)
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Organisering kring hot och risk
- 2007
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Hur hanteras blödarfeberviruset Marburg, hur förbereder man sig för ett eventuellt utbrott av fågelinfluensan, hur kalkylerar man hälsorisker i Europa och Sverige och hur hanterar man risk i samband med äventyrsturism? Vad har stormen Gudrun lärt oss om att hantera akuta situationer och hur skapar katastrofer som Tjörnbron handlingsföreträde i form av särskilda förutsättningar för organisering? Detta är några exempel på studier inkluderade i Organisering kring hot och risk. Boken tittar även närmare på hur man hanterar effekter av datorkriser, hur konst och vad betraktaren bedömer som hot kan bidra till skapande av handlingsnät samt hur tv-serien Kommissionen belyser det svenska beredningsarbetet. Författarna visar att karaktären av organisering kring hot och risk är beroende av tidpunkten: innan, under eller efter en katastrof eller en hotfull händelse. Beredningsarbetet består av resursmobilisering, att skissa planer, att bygga upp strukturer samt bygga eller mobilisera nätverk. När katastrofen väl inträffar visar det sig dock att även de bästa planer inte alltid fungerar som man vill och responsen på de faktiska händelserna består av improvisation samt av att bygga handlingskedjor och handlingsnät. Det finns inget recept på hur man skall organisera kring hot och risk men boken har identifierat ett återkommande problem: varje misslyckande verkar leda till slutsatsen att det behövs mer av planer och strukturer. Författarna hävdar motsatsen. Bokens budskap är att istället för att skapa oändliga planer och strukturer skall man öva lämpliga skickligheter och improvisationsförmåga. Boken vänder sig till studerande inom organisationsteori respektive riskhantering på universitet och högskola samt yrkesverksamma inom krisberedskap och riskhantering.
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| 6. |
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| 7. |
- Diedrich, Andreas, 1973, et al.
(författare)
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Exploring the Performativity Turn in Management Studies
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- One of the contemporary “turns” in management studies is the “performativity” turn. In this paper, we present a genealogy of the concept of performativity as it has been used in management and organization studies (MOS). Starting with the work of Austin, Bateson, Goffman and Lyotard, we move on to more recent debates surrounding the use of the concept by Butler and the STS researchers Callon, Latour and Law, as well as how their ideas have been further translated within MOS. The focus is on how the concept is defined and on the areas of study where performativity has been used. Taken together, the approach to performativity employed has implications for how the concept is understood and translated. Finally, we discuss the particular ontological position of the performative perspective, and its methodological consequences.
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| 8. |
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| 9. |
- Eijsbouts, C., et al.
(författare)
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Genome-wide analysis of 53,400 people with irritable bowel syndrome highlights shared genetic pathways with mood and anxiety disorders
- 2021
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 53:11, s. 1543-1552
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Tidskriftsartikel (refereegranskat)abstract
- Irritable bowel syndrome (IBS) results from disordered brain–gut interactions. Identifying susceptibility genes could highlight the underlying pathophysiological mechanisms. We designed a digestive health questionnaire for UK Biobank and combined identified cases with IBS with independent cohorts. We conducted a genome-wide association study with 53,400 cases and 433,201 controls and replicated significant associations in a 23andMe panel (205,252 cases and 1,384,055 controls). Our study identified and confirmed six genetic susceptibility loci for IBS. Implicated genes included NCAM1, CADM2, PHF2/FAM120A, DOCK9, CKAP2/TPTE2P3 and BAG6. The first four are associated with mood and anxiety disorders, expressed in the nervous system, or both. Mirroring this, we also found strong genome-wide correlation between the risk of IBS and anxiety, neuroticism and depression (rg > 0.5). Additional analyses suggested this arises due to shared pathogenic pathways rather than, for example, anxiety causing abdominal symptoms. Implicated mechanisms require further exploration to help understand the altered brain–gut interactions underlying IBS. © 2021, The Author(s).
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| 10. |
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| 11. |
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| 12. |
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| 13. |
- Henstrom, M., et al.
(författare)
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Functional variants in the sucrase-isomaltase gene associate with increased risk of irritable bowel syndrome
- 2018
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Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 67:2, s. 263-270
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Tidskriftsartikel (refereegranskat)abstract
- Objective IBS is a common gut disorder of uncertain pathogenesis. Among other factors, genetics and certain foods are proposed to contribute. Congenital sucraseisomaltase deficiency (CSID) is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to IBS. We tested sucrase-isomaltase (SI) gene variants for their potential relevance in IBS. Design We sequenced SI exons in seven familial cases, and screened four CSID mutations (p.Val557Gly, p. Gly1073Asp, p.Arg1124Ter and p.Phe1745Cys) and a common SI coding polymorphism (p.Val15Phe) in a multicentre cohort of 1887 cases and controls. We studied the effect of the 15Val to 15Phe substitution on SI function in vitro. We analysed p.Val15Phe genotype in relation to IBS status, stool frequency and faecal microbiota composition in 250 individuals from the general population. Results CSID mutations were more common in patients than asymptomatic controls (p=0.074; OR=1.84) and Exome Aggregation Consortium reference sequenced individuals (p=0.020; OR=1.57). 15Phe was detected in 6/7 sequenced familial cases, and increased IBS risk in case-control and population-based cohorts, with best evidence for diarrhoea phenotypes (combined p=0.00012; OR=1.36). In the population-based sample, 15Phe allele dosage correlated with stool frequency (p=0.026) and Parabacteroides faecal microbiota abundance (p=0.0024). The SI protein with 15Phe exhibited 35% reduced enzymatic activity in vitro compared with 15Val (p<0.05). Conclusions SI gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to IBS. This may help the identification of individuals at risk, and contribute to personalising treatment options in a subset of patients.
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| 14. |
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| 15. |
- Karling, Pontus, et al.
(författare)
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Function and dysfunction of the colon and anorectum in adults: working team report of the Swedish Motility Group (SMoG).
- 2009
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Ingår i: Scandinavian journal of gastroenterology. - : Informa UK Limited. - 1502-7708 .- 0036-5521. ; 44:6, s. 646-60
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Forskningsöversikt (refereegranskat)abstract
- Symptoms of fecal incontinence and constipation are common in the general population. These can, however, be unreliably reported and are poorly discriminatory for underlying pathophysiology. Furthermore, both symptoms may coexist. In the elderly, fecal impaction always must be excluded. For patients with constipation, colon transit studies, anorectal manometry and defecography may help to identify patients with slow-transit constipation and/or pelvic floor dysfunction. The best documented medical treatments for constipation are the macrogols, lactulose and isphagula. Evolving drugs include lubiprostone, which enhances colonic secretion by activating chloride channels. Surgery is restricted for a highly selected group of patients with severe slow-transit constipation and for those with large rectoceles that demonstrably cause rectal evacuatory impairment. For patients with fecal incontinence that does not resolve on antidiarrheal treatment, functional and structural evaluation with anorectal manometry and endoanal ultrasound or magnetic resonance (MR) of the anal canal may help to guide management. Sacral nerve stimulation is a rapidly evolving alternative when other treatments such as biofeedback and direct sphincter repair have failed. Advances in understanding the pathophysiology as a guide to treatment of patients with constipation and fecal incontinence is a continuing important goal for translational research. The content of this article is a summary of presentations given by the authors at the Fourth Meeting of the Swedish Motility Group, held in Gothenburg in April 2007.
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| 16. |
- Khan, M. Shafiquzzaman, et al.
(författare)
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Annoyance of idling diesel engine noise evaluated by multivariate analysis
- 1995
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Ingår i: Noise Control Engineering Journal. - : Institute of Noise Control Engineering (INCE). - 0736-2501 .- 2168-8710. ; 43:6, s. 197-207
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Tidskriftsartikel (refereegranskat)abstract
- Judgments of annoyance caused by the sound of an idling diesel engine were determined by 80 subjects. The diesel-engine sounds were recorded and the spectra were subsequently modified electronically to produce various test signals. The subjects listened to eight different sounds in a paired-comparison procedure. Each sound signal was presented to the subjects at a time-averaged A weighted sound level of 80 dB. Two different prediction models of the annoyance response were developed by use of principal component analysis and partial least-squares regression. A new descriptor, the 'ear resonance range,' was discovered as a result of employing these analysis methods. The first prediction model, based on psychoacoustic measures, utilized the ear resonance range along with loudness and kurtosis to predict the annoyance judgments of the test signals. The second model utilized critical-band sound-pressure levels as the basis for the annoyance predictions. Both models were confirmed by internal and external validations and gave good predictions. The critical-band sound-pressure-level prediction model may provide a better means than the psychoacoustic-measure model to evaluate options for minimizing the annoyance of the sound from an idling diesel engine.
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| 17. |
- Langley, Ann, et al.
(författare)
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Boundary work among groups, occupations, and organizations: From cartography to process
- 2019
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Ingår i: Academy of Management Annals. - : Academy of Management. - 1941-6520 .- 1941-6067. ; 13:2, s. 704-736
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Tidskriftsartikel (refereegranskat)abstract
- © Academy of Management Annals. This article reviews scholarship dealing with the notion of “boundary work,” defined as purposeful individual and collective effort to influence the social, symbolic, material, or temporal boundaries, demarcations; and distinctions affecting groups, occupations, and organizations. We identify and explore the implications of three conceptually distinct but interrelated forms of boundary work emerging from the literature. Competitive boundary work involves mobilizing boundaries to establish some kind of advantage over others. In contrast, collaborative boundary work is concerned with aligning boundaries to enable collaboration. Finally, configurational boundary work involves manipulating patterns of differentiation and integration among groups to ensure that certain activities are brought together, whereas others are kept apart, orienting the domains of competition and collaboration. We argue that the notion of boundary work can contribute to the development of a uniquely processual view of organizational design as open-ended, and continually becoming, an orientation with significant future potential for understanding novel forms of organizing, and for integrating agency, power dynamics, materiality, and temporality into the study of organizing.
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| 18. |
- Lindberg, Kajsa, 1969, et al.
(författare)
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Assembling Health Care Organizations. Practice, Materiality and Institutions
- 2012
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- The health care sector is the largest sector of the economy in most developed countries. With ageing populations in Europe and North-America, the health sector is expected to undergo significant changes in the future as it needs to handle more patients within stable budgets. Given its weight and importance in economic and financial terms and its importance for citizens, the health care sector has been extensively studied in various disciplines, including management studies. In many cases, health care organizations are examined from a systems theory perspective or a field of professional expertise and jurisdictional struggles. Assembling Health Care Organizations: Practices, Materialities, and Institutions integrates an institutional theory perspective and a materialist view of the technologies, devices, biological specimens, and other material resources mobilized and put to work in health care work.
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| 19. |
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| 20. |
- Lindberg, Kajsa, 1969, et al.
(författare)
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Emergent coordination and situated learning in a Hybrid OR: The mixed blessing of using radiation
- 2019
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Ingår i: Social Science & Medicine. - : Elsevier BV. - 0277-9536. ; 228, s. 232-239
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Tidskriftsartikel (refereegranskat)abstract
- Mobilising knowledge and coordinating actions in order to make use of new innovations and technologies is a major challenge in the health care sector. Drawing upon a longitudinal, qualitative study of a Hybrid Operating Room in Sweden, we illustrate how the staff from a variety of medical specialties need to coordinate their tasks and competencies, and learn how to use the technology in a safe way. This study shows that learning across highly-professionalized communities is a recursive process of emergent coordination and situated learning, which includes the acknowledgement of others' expertise, task interdependence, and the pragmatic accommodation of latitude and control. Moreover, there was continuous negotiations between the different communities about what should constitute approved practice based on the task being performed. This obstructed the development of a dominant community with the authority to independently exclude other communities. We thus conclude that emergent coordination of tasks and expertise is an important aspect of learning how to use technologies that break with conventions of established and previously separated practices.
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| 21. |
- Lindberg, Kajsa, 1969, et al.
(författare)
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Objects-in-Use and Organizing in Action Nets: A Case of an Infusion
- 2013
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Ingår i: Journal of Management Inquiry. - : SAGE Publications. - 1552-6542 .- 1056-4926. ; 22:2, s. 212-227
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Tidskriftsartikel (refereegranskat)abstract
- In this article, the authors engage in, and contribute to, the discussion about the role of objects (material arrangements) in processes of organizing. The point of departure of the study was a critical incident at a hospital when a drop infusion pump failed. By following the action, that is, to apply an action net perspective, initiated by incident aiming to secure the ongoing care and treatment of patients on the ward, the authors are able to illustrate the relation between objects-in-use (such as boundary objects) and ongoing organizing practices, and how such organizing activities are dependent on, and conditioned by, material arrangements and objects. Furthermore, they also show that objects, far from being stable entities, are also being constructed, deconstructed, and reconstructed—dependent on what is appropriate in a specific time and place, and as part of ongoing organizing.
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| 22. |
- Lindberg, Kajsa, 1969, et al.
(författare)
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One table - Several practices: Material controversies in the hybrid operating room
- 2018
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Ingår i: Hoholm T., La Rocca A., Aanestad M. (eds.): Controversies in Healthcare Innovation. - London : Palgrave Macmillan. - 9781137557803 ; , s. 53-74
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- In Chapter 3, Lindberg and Walter present a study of the introduction and use of a ‘hybrid operating room’ at a major Swedish hospital. Hybrid operating rooms are complex as they are both technology and knowledge intensive, and imply the collaboration of several disciplinary groups with different specializations and multiple understandings. Based on field material from an ethnographically inspired longitudinal study, the authors describe negotiations between the stubborn materiality of the table used in this particular room and the need to perform safe medical procedures, based on previous experiences gained in their separate practices. The table was translated into a multifunctional tool that brought about new types of flexibility, enabling as well as restricting what and how can be done in the hybrid room.
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| 23. |
- Lindberg, Kajsa, 1969, et al.
(författare)
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Performing boundary work: The emergence of a new practice in a hybrid operating room
- 2017
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Ingår i: Social Science & Medicine. - : Elsevier BV. - 0277-9536. ; 182, s. 81-88
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses the processes of boundary work, in relation to the introduction of new technology, unfolding during the emergence of new medical practices. Inspired by Gieryn's fluid and practical view of boundaries and boundary work, and by Actor-Network Theory's description of scripting processes, we study the processes of negotiating and (re-)constructing boundaries in order to reveal both the interactions between different kinds of boundary work and their situatedness in the context of the emerging practice. We conducted a longitudinal and qualitative study of a generic Hybrid Operating Room at a Swedish university hospital, where sophisticated imaging devices are combined with open surgery procedures in a single room; consequently, medical requirements regarding radiology, surgery and anesthesia, as well as the specificities of the new technology, all need to be met at the same time. The study shows how the visibility of boundaries is a result of as well as a condition for boundary work, how boundary work is a dynamic and iterative process, and how it unfolds in a recursive relationship between practice and boundaries. (C) 2017 Elsevier Ltd. All rights reserved.
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| 24. |
- Lindberg, Robert, et al.
(författare)
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C-cavity fiber laser employing a chirped fiber Bragg grating for electrically gated wavelength tuning
- 2020
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Ingår i: Optics Express. - : OSA - The Optical Society. - 1094-4087. ; 28:7, s. 9208-9215
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Tidskriftsartikel (refereegranskat)abstract
- We present a novel C-cavity concept for tunable lasers. The laser is based on a semiconductor optical amplifier (SOA), serving both as a gain medium as well as a modulator, and a chirped fiber Bragg grating (C-FBG) which acts as the end mirrors on both cavity ends. Driving the SOA with a pulse pair with variable delay enables wavelength tuning by targeting different regions in the C-FBG with the circulating pulse. The cavity design allows for wide tuning while maintaining a constant repetition rate, we show a tuning range of 35 nm -limited by the C-FBG's reflection bandwidth. Time-multiplexed operation with four different wavelengths is also demonstrated. Furthermore, the laser performance and dynamics under different operating conditions are analyzed and discussed.
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| 25. |
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| 26. |
- Margulis, Walter, et al.
(författare)
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Intracavity interrogation of an array of fiber Bragg gratings
- 2021
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Ingår i: Optics Express. - : OSA - The Optical Society. - 1094-4087. ; 29:1, s. 111-118
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we explore the interrogation of an array of fiber Bragg gratings as part of a laser cavity. A semiconductor optical amplifier in a sigma-shaped fiber cavity provides gain and is gated periodically at a rate that matches the roundtrip time associated with each grating of the array. The interrogator exhibits clear laser properties such as a threshold and linewidth narrowing. Besides improving the signal-to-noise ratio and enabling the re-use of wavelengths, it is found that this interrogation scheme enables monitoring of weak gratings spaced by less than 1 cm. Intracavity grating interrogation studied here is found to be a simple and powerful way to increase the number of sensor points for industrial applications.
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| 27. |
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| 28. |
- Wheeler, David C., et al.
(författare)
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The dapagliflozin and prevention of adverse outcomes in chronic kidney disease (DAPA-CKD) trial : baseline characteristics
- 2020
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Ingår i: Nephrology, Dialysis and Transplantation. - OXFORD ENGLAND : Oxford University Press (OUP). - 0931-0509 .- 1460-2385. ; 35:10, s. 1700-1711
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Tidskriftsartikel (refereegranskat)abstract
- Background. The Dapagliflozin and Prevention of Adverse outcomes in Chronic Kidney Disease (DAPA-CKD; NCT03036150) trial was designed to assess the effect of the sodium-glucose co-transporter 2 (SGLT2) inhibitor dapagliflozin on kidney and cardiovascular events in participants with CKD with and without type 2 diabetes (T2D). This analysis reports the baseline characteristics of those recruited, comparing them with those enrolled in other trials. Methods. In DAPA-CKD, 4304 participants with a urinary albumin:creatinine ratio (UACR) <= 200mg/g and estimated glomerular filtration rate (eGFR) between 25 and 75mL/min/1.73m(2) were randomized to dapagliflozin 10mg once daily or placebo. Mean eGFR was 43.1mL/min/1.73m(2) and median UACR was 949 mg/g (108mg/mmol). Results. Overall, 2906 participants (68%) had a diagnosis of T2D and of these, 396 had CKD ascribed to a cause other than diabetes. The most common causes of CKD after diabetes (n = 2510) were ischaemic/hypertensive nephropathy (n = 687) and chronic glomerulonephritis (n = 695), of which immunoglobulin A nephropathy (n = 270) was the most common. A total of 4174 participants (97%) were receiving an angiotensinconverting enzyme inhibitor or angiotensin receptor blocker, 1882 (43.7%) diuretics, 229 (5.3%) mineralocorticoid receptor antagonists and 122 (2.8%) glucagon-like peptide 1 receptor agonists. In contrast to the Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE), the DAPA-CKD trial enrolled participants with CKD due to diabetes and to causes other than diabetes. The mean eGFR of participants in the DAPA-CKD trial was 13.1mL/min/1.73m(2) lower than in CREDENCE, similar to that in the Finerenone in Reducing Kidney Failure and Disease Progression in DKD (FIDELIO-DKD) trial and the Study Of diabetic Nephropathy with AtRasentan (SONAR). Conclusions. Participants with a wide range of underlying kidney diseases receiving renin-angiotensin system blocking therapy have been enrolled in the DAPA-CKD trial. The trial will examine the efficacy and safety of dapagliflozin in participants with CKD Stages 2-4 and increased albuminuria, with and without T2D.
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| 29. |
- Yang, Xiong, et al.
(författare)
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Continuously tunable, narrow-linewidth laser based on a semiconductor optical amplifier and a linearly chirped fiber Bragg grating
- 2019
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Ingår i: Optics Express. - : Optical Society of America. - 1094-4087. ; 27:10, s. 14213-14220
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Tidskriftsartikel (refereegranskat)abstract
- We describe a simple, narrow-linewidth, tunable fiber-based laser with a high degree of tuning accuracy. A polarization independent semiconductor optical amplifier (SOA) is used as the gain medium in a unidirectional fiber ring cavity with a circulator connected to a 6-meter long chirped fiber Bragg grating (CFBG). The laser wavelength is chosen by setting the modulation frequency of the SOA the same as the harmonics of the fundamental repetition rate of the light reflected at a specific point on the CFBG. Careful management of the drive current and pulse width helps to generate laser light of narrow linewidth (less than 0.03 nm) with low power variation (1.46 dB) over a tuning range of 40 nm.
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| 30. |
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