| 1. |
- Billing, Matilda, et al.
(författare)
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Signaling via Smad2 and Smad3 is dispensable for adult murine hematopoietic stem cell function in vivo
- 2017
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Ingår i: Experimental Hematology. - : Elsevier BV. - 0301-472X.
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Tidskriftsartikel (refereegranskat)abstract
- Transforming growth factor-β (TGFβ) is a member of a large family of polypeptide growth factors. TGFβ signals mainly through the intracellular proteins Smad2 and Smad3, which are highly similar in amino acid sequence identity. A number of studies have shown that these proteins, dependent on context, have distinct roles in the TGFβ signaling pathway. TGFβ is one of the most potent inhibitors of hematopoietic stem and progenitor cell proliferation in vitro, but its role in hematopoiesis in vivo is still being determined. To circumvent possible redundancies at the receptor level and to address specifically the role of the Smad circuitry downstream of TGFβ and activin in hematopoiesis, we studied the effect of genetically deleting both Smad2 and Smad3 in adult murine hematopoietic cells. Indeed, TGFβ signaling is impaired in vitro in primitive bone marrow (BM) cells of Smad2 and Smad3 single knockout models. However, blood parameters appear normal under steady state and in the transplantation setting. Interestingly, upon deletion of both Smad2 and Smad3 in vivo, mice quickly develop a lethal inflammatory disease, suggesting that activin/TGFβ signaling is crucial for immune cell homeostasis in the adult context. Furthermore, concurrent deletion of Smad2 and Smad3 in BM cells in immune-deficient nude mice did not result in any significant alterations of the hematopoietic system. Our findings suggest that Smad2 and Smad3 function to mediate crucial aspects of the immunoregulatory properties of TGFβ, but are dispensable for any effect that TGFβ has on primitive hematopoietic cells in vivo.
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| 2. |
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| 3. |
- Dahl, Maria, et al.
(författare)
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Bone marrow transplantation without myeloablative conditioning in a mouse model for Diamond-Blackfan anemia corrects the disease phenotype
- 2021
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Ingår i: Experimental Hematology. - : Elsevier BV. - 0301-472X. ; 99, s. 2-53
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Tidskriftsartikel (refereegranskat)abstract
- Diamond-Blackfan anemia (DBA) is a congenital erythroid hypoplasia caused by a functional haploinsufficiency of genes coding for ribosomal proteins. Among these genes, the ribosomal protein S19 (RPS19) gene is the most frequently mutated. Previously, a mouse model deficient in RPS19 was developed by our laboratory, which recapitulates the hematopoietic disease phenotype by manifesting pathologic features and clinical symptoms of DBA. Characterization of this model revealed that chronic RPS19 deficiency leads to exhaustion of hematopoietic stem cells and subsequent bone marrow (BM) failure. In this study, we evaluated a nonmyeloablative conditioning protocol for BM transplants in RPS19-deficient mice by transplanting wild-type BM cells to RPS19-deficient recipients given no conditioning or sublethal doses of irradiation before transplant. We describe full correction of the hematopoietic phenotype in mice given sublethal doses of irradiation, as well as in animals completely devoid of any preceding irradiation. In comparison, wild-type animals receiving the same preconditioning regimen and number of transplanted cells exhibited significantly lower engraftment levels. Thus, robust engraftment and repopulation of transplanted cells can be achieved in reduced-intensity conditioned RPS19-deficient recipients. As gene therapy studies with autologous gene-corrected hematopoietic stem cells are emerging, we propose the results described here can guide determination of the level of conditioning for such a protocol in RPS19-deficient DBA. On the basis of our findings, a relatively mild conditioning strategy would plausibly be sufficient to achieve sufficient levels of engraftment and clinical success.
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| 4. |
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| 5. |
- Dahl, Matilda, 1978-
(författare)
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Granskningssamhället och det nya Europa : när de Baltiska staterna sattes på prov
- 2012
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- I den här skriften analyseras det framväxande granskningssamhället, med utgångspunkt i hur de baltiska staterna synades inför EU-inträdet. Då länderna skulle bli en del av det nya Europa öppnade de sig för granskning av bl.a. EU-kommissionen, EBRD och Transparency International. Men frågan är om granskning verkligen är en så neutral praktik som det ges sken av?Genom att jämföra granskning av stater med revision av företag visar författaren på att granskningssamhället inte bara skapar ordning, utan ensärskild ordning. Granskningsförfaranden blir slagkraftiga styrningsmekanismer mot bestämda mål, just eftersom de oftast framställs och uppfattas som värderingsfria och neutrala teknologier. rapporter, siffror och rankningar reflekterar verkligheten samtidigt som de är med och konstruerar den.
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| 6. |
- Dahl, Matilda
(författare)
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Går det att granska finansmarknaden?
- 2014
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Ingår i: Veckans affärer. - Stockholm : Specialtidningsförlaget. - 0506-4406.
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 7. |
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| 8. |
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| 9. |
- Dahl, Matilda, 1978-
(författare)
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Je suis Gemeinschaft
- 2020
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Ingår i: Om undran inför företagsekonomin. - : Santérus Academic Press Sweden. - 9789173591560
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 10. |
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| 11. |
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| 12. |
- Dahl, Matilda, 1978-
(författare)
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Reform and rescue : International organizations and the organization of markets
- 2018
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Ingår i: Organizing and reorganizing markets. - : Oxford University Press. - 9780198815761 - 9780191853289
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Bokkapitel (refereegranskat)abstract
- Organizing and Reorganizing Markets is an edited volume that brings organization theory to the study of markets. The differences between markets and organizations are often exaggerated. Both are organized. Organizing exists in addition to other processes and phenomena that form markets: the mutual adaption among sellers and buyers as described in mainstream economics and the institutions described in institutional economics and economic sociology. Market organization can be analysed with the same type of theories used for analysing organization within formal organizations. Through the use of many empirical examples, the book demonstrates how this can be done. We argue that the way a certain market is organized can be understood as the (intermediate) result of previous organizing processes. We discuss such questions as ‘What drives market organizing and reorganizing processes? What makes various organizations intervene as market organizers? And how are the specific contents of market organization determined?’ The answers to these questions help us to analyse similarities and differences among organizing processes in formal organizations and those in markets. The arguments are illustrated by in-depth studies of many types of markets. The book is intended to open up markets as a field of study for scholars of organization. Although the chapters have different authors, they use and elaborate upon the same general theoretical framework. The book contributes to the issue of organization outside and among organizations where a fundamental concept is that of partial organization.
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| 13. |
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| 14. |
- Dahl, Matilda, 1978-
(författare)
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States under scrutiny : International organizations, transformation and the construction of progress
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Opinions, rankings and evaluations of states’ development are proliferating. In the context of the transformation and EU accession of the Baltic States, there were many organizations involved in the scrutiny of their efforts to become accepted as modern and European. This scrutiny directed towards states can be seen as a new practice of transnational regulation. Especially in times of major transformation, as was the case in the Baltic States after the collapse of the Soviet bloc, monitoring and evaluation of achievements can be expected to shape how reforms were prioritized and how problems were perceived. In order to gain a better understanding of these transformations it is necessary to study the practice of organizations that scrutinize the states.The aim of the thesis is to analyze the role of scrutiny as a practice of transnational regulation. By analyzing how international organizations scrutinize states, this thesis adds knowledge to how transforming states are constructed in the everyday practices of scrutiny. A main argument is that by evaluating and reporting on states, international organizations can be seen as ‘auditors’ of transformations in states. The thesis compares three such ‘auditors’ and their respective relations to the states under scrutiny, namely: the European Commission, the European Bank for Reconstruction and Development (EBRD) and the NGO Transparency International. The thesis contributes to discussions about the role of transnational regulation in the transformation of states. By comparing the three cases of scrutiny it is concluded that scrutiny produces both comfort and critique for and about these transforming states. In addition, through processes of scrutinizing, states are constructed as auditable and comparable. Scrutiny also inscribes states into a story about progress, it thus offers hope about reforms and of a better future.
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| 15. |
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| 16. |
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| 17. |
- Dahl, Matilda, 1978-, et al.
(författare)
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The poetic teaching space: Gaston Bachelard and a third realm in management education
- 2021
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Ingår i: Culture and Organization. - : Taylor & Francis. - 1475-9551 .- 1477-2760. ; 28:3-4, s. 362-377
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Tidskriftsartikel (refereegranskat)abstract
- How to make students and teachers stopStop and think and feelReading slowReading aloudSavouring silenceBeing there with all our emotions and bodiesAn experimentNot a social experimentNot a psychological experimentBut a poeticAccompanied by a French philosopherGaston Bachelard was always therein the atmosphereOur classroom practiceWith our master’s studentsIn sustainable managementWe searched for poetic momentsTurned into a conversationTurned into a paperA paper about the poetics of teachingPhenomenologizing philosophyRupturing classrooms
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| 18. |
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| 19. |
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| 20. |
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| 21. |
- Dahl, Matilda, 1978-, et al.
(författare)
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Writing, dreams and imagination
- 2020. - 1
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Ingår i: Aesthetics, Organization, and Humanistic Management. - : Routledge. - 9781003091530 ; , s. 47-58
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Studies of philosophy have shown that daydreaming is essential for our imagination. Through daydreaming, the present reality can be expanded as new life worlds take shape. How this happens and how the dreamt realities play a role in today’s organizations we, however, know little about. In this chapter we are working on how to make sense of our research material about daydreaming and trying out different ways of how to write about it. In these attempts we face a fundamental question: is it a dream in itself that an academic text, about a woman who manages (and daydreams on) her farm, can give rise to poetic images?As we search for ways of writing that can give rise to poetic images, we experiment with a triptych in the form of photos, poetry, and a portrait. It turns out to become a kind of triangulation among the pictures we see through the lenses of our cameras, an impressionistic biography, and a rendering of what we hear when we listen to a farmer; as if the poetic image would emerge from these impressions offered by our studied organization. The chapter attempts to open up to ways of writing where different images can be born to evoke poetic aspects of the material at hand rather than merely represent its factual “evidence.”Working with the triptych, and hopefully in reading it, the different texts create a stop in the flow of reading, enabling us to pause and inviting us to a journey.
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| 22. |
- Fredolini, Claudia, et al.
(författare)
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Proteome profiling of home-sampled dried blood spots reveals proteins of SARS-CoV-2 infections
- 2024
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Ingår i: Communications Medicine. - : Springer Nature. - 2730-664X. ; 4:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Self-sampling of dried blood spots (DBS) offers new routes to gather valuable health-related information from the general population. Yet, the utility of using deep proteome profiling from home-sampled DBS to obtain clinically relevant insights about SARS-CoV-2 infections remains largely unexplored.Methods Our study involved 228 individuals from the general Swedish population who used a volumetric DBS sampling device and completed questionnaires at home during spring 2020 and summer 2021. Using multi-analyte COVID-19 serology, we stratified the donors by their response phenotypes, divided them into three study sets, and analyzed 276 proteins by proximity extension assays (PEA). After normalizing the data to account for variances in layman-collected samples, we investigated the association of DBS proteomes with serology and self-reported information.Results Our three studies display highly consistent variance of protein levels and share associations of proteins with sex (e.g., MMP3) and age (e.g., GDF-15). Studying seropositive (IgG+) and seronegative (IgG-) donors from the first pandemic wave reveals a network of proteins reflecting immunity, inflammation, coagulation, and stress response. A comparison of the early-infection phase (IgM+IgG-) with the post-infection phase (IgM-IgG+) indicates several proteins from the respiratory system. In DBS from the later pandemic wave, we find that levels of a virus receptor on B-cells differ between seropositive (IgG+) and seronegative (IgG-) donors.Conclusions Proteome analysis of volumetric self-sampled DBS facilitates precise analysis of clinically relevant proteins, including those secreted into the circulation or found on blood cells, augmenting previous COVID-19 reports with clinical blood collections. Our population surveys support the usefulness of DBS, underscoring the role of timing the sample collection to complement clinical and precision health monitoring initiatives. The COVID-19 pandemic has posed multiple challenges to healthcare systems. A significant gap that remains is a lack of understanding of the impact of SARS-CoV-2 on individuals who did not seek or require hospitalization. To address this, we distribute self-sampling devices to random citizens, aiming to analyze how blood protein levels are affected in people who have had COVID-19 but had no or mild symptoms. Conducting multiple molecular measurements in dried blood, our study confirms clinically known markers and their relationship to infection stages, even if the donors themselves collect the sample. Our work highlights the potential of combining self-sampling with laboratory methods to provide useful information on human health. This convenient patient-centric sampling approach may potentially be useful when studying other diseases. Fredolini et al. present a proteomics analysis of home-sampled dried blood spots taken from the general population in Stockholm during the COVID-19 pandemic. The study provides insights into the molecular effects of SARS-CoV-2 infection in non-hospitalized individuals and demonstrates the compatibility of self-sampled blood spots with proteomics.
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| 23. |
- Fredriksson, Henrik, et al.
(författare)
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Förstudie – Datadriven analys av restider
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Det uppkopplade samhället möjliggör kontinuerlig insamling av trafikdata genom de moderna fordonens navigationssystem, så väl som genom mobiltelefoner och andra GPS-enheter. Den ökade tillgången till trafikdata ger möjligheter analysera att trafiksystemet ur flera olika perspektiv. En typ av trafikdata som kan extraheras ur GPS-data är fordonshastigheter. Genom att analysera hur fordonshastigheter förändras över tid och identifiera avvikelser från ett normaltillstånd så skulle det vara möjligt att upptäcka och förutsäga potentiella brister i trafiksystemet. Många gånger upptäcks brister i infrastrukturen i ett relativt sent skede vilket i sin tur kan innebära både omfattande och kostsamma åtgärder för att komma till rätta med problemen.Syftet med förstudien har varit att utveckla och utvärdera metoder och modeller för att detektera brister och identifiera hastigheter som relativt avviker från normaltillståndet, dvs ett fokus på fordonshastigheter som framför allt är ovanligt låga. Utgångspunkten har också varit att finna lämplig metod för att modellera trafiksituationen med hjälp av uppmätta fordonshastigheter. Det vill säga metoder som syftar till att ur ett övergripande perspektiv beskriva normaltillståndet längs med de studerade vägsträckorna. Analyser av normaltillståndets förändring över tid öppnar upp möjligheten att detektera om brister relaterat till vägsträckors kapacitet och framkomlighet uppstått eller avgöra om normaltillståndet på en vägsträcka är stabilt eller förändras över tid.Det är framför allt de relativt låga fordonshastigheterna som uppstår som blir en indikator på att en vägsträcka har brister. Därför föreslås en metod för att systematiskt identifiera och gruppera uppmätta fordonshastigheter i låga, normala och höga hastigheter. En utgångspunkt har varit robusthet och att möjliggöra jämförelser av hastigheter för olika vägsträckor med olika attribut som antal körfält och skyltad hastighet med varandra. Vi presenterar även ett nytt mått som beskriver hur gruppen med relativt låga hastigheter förhåller sig till friflödeshastigheten som till exempel den skyltade hastigheten. Syftet med måttet är att kvantifiera framkomligheten på en vägsträcka eller vägsegment. Existerande mått och indikatorer baseras idag på fordonshastigheter som spänner från låga till höga hastigheter. Vi har i denna kontext tagit fram ett mått som endast tar hänsyn till vad som anses vara låga hastigheter och friflödeshastighet.Inom förstudien så har även en metod baserad på klusteranalys använts för de studerade vägsträckorna. Klusteranalys har i olika sammanhang visat sig effektivt för att kategorisera och detektera återkommande mönster i hastighetsprofiler. Syftet med klusteranalysen är att undersöka om det finns någon koppling mellan hastighetsprofiler som har liknande beteende och till exempel veckodag och tidpunkt. Genom klusteranalys skulle det vara möjligt att inte bara detektera vilka vägsträckor där det uppstår problem, utan det skulle även vara möjligt att prognostisera vid vilka veckodagar och tidpunkter där det finns risk att köer och andra problem kan uppstå.Förstudien är begränsad till användning av fordonhastigheter som datakälla och de framtagna metoderna och modellerna visar att det finns potential att frikoppla sig från andra datakällor som till exempel fordonsflöden för att detektera brister eller avvikelser som skulle kunna indikera brister i transportsystemet.
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| 24. |
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| 25. |
- Helin, Jenny, et al.
(författare)
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Bachelard’s Backdoor to Happy Business School Phenomenology
- 2023
-
Ingår i: The Oxford Handbook of Phenomenologies and Organization Studies. - : Oxford University Press. - 9780191956508 - 9780192865755 - 0192865757 ; , s. 330-346
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Bachelard, a philosopher, helps introduce a phenomenological sensitivity to organizational investigations. The poetic and the scientific are two different but compatible aspects of organizing. By abandoning a science of organizing dominated by analytical philosophy that dominates US organization theory, we can reconnect to the continental traditions of Bachelard, as well as Husserl and Schütz. Phenomenology returns to questions of reason in lived experiences, forgotten when social science only focuses on instrumental rationality and artificial intelligence.
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| 26. |
- Helin, Jenny, 1972-, et al.
(författare)
-
Caravan Poetry : An Inquiry on Four Wheels
- 2020
-
Ingår i: Qualitative Inquiry. - : SAGE PUBLICATIONS INC. - 1077-8004 .- 1552-7565. ; 26:6, s. 633-638
-
Tidskriftsartikel (refereegranskat)abstract
- How can we create possibilities for a generative moment between the research participants and ourselves? In a study about (day)dreaming, we searched for ways of doing our research in which we could meet and jointly explore the becoming of life and important matters through our experiences of dreaming. Inspired by Gaston Bachelard's phenomenology of dreaming and in particular his book The Poetics of Space, in which he emphasized the importance of small, intimate spaces for poetic moments to occur, we decided to buy a small countryside caravan. Through this inquiry into a new spatiotemporality for our research encounters, we experienced how the caravan offers a rupture from the mundane ongoingness enabling us to reconnect to the moment, the place, each other, and ourselves. This rupture awakens the verticality of time allowing us to be looking anew and making novel connections. What may be seen as self-evident, but it was not for us, is the recognition that in developing research practices for studying dreaming, we had to first start dreaming ourselves.
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| 27. |
- Helin, Jenny
(författare)
-
Hemkomstens ekonomi : Företagande bortom erövring
- 2023
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- Forskning visar att många av de problem vi har i dag – klimatkris, artdöd, monokultur och ekonomisk ojämlikhet – är en konsekvens av den expansiva erövring som företagande drivs av. Samtidigt är denna erövringens ekonomi så självklar att vi knappt lägger märke till den. Som alternativ introduceras här hemkomstens ekonomi, som handlar om att komma hem i sitt företagande genom att verka i hyperlokala gemenskaper och att varsamt ta hand om det existerande.Hemkomstens ekonomi åskådliggörs i tre företagarporträtt, där text och foton sammanfogas för att skapa en helhetsbild. När allt starkare röster höjs för att företag behöver ställa om, kan detta vara en del av den omställning vi behöver se?
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| 28. |
- Helin, Jenny, et al.
(författare)
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Showering of words that matter
- 2023
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Ingår i: <em>How to Write Differently: A Quest for Meaningful Academic Writing</em>. - : Edward Elgar Publishing.
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 29. |
- Helin, Jenny
(författare)
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Slow reading of deep data
- 2023
-
Ingår i: Feminist Methodologies in Organization and Managment Studies. - : Oxford University Press.
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 30. |
- Helin, Jenny, 1972-, et al.
(författare)
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The power of daydreaming : the aesthetic act of a new beginning
- 2022
-
Ingår i: Culture and Organization. - : Routledge. - 1475-9551 .- 1477-2760. ; 28:1, s. 64-78
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Tidskriftsartikel (refereegranskat)abstract
- What can we learn from a better understanding of the process of daydreaming in an organizational context? That is the main question underpinning this study. Based on a field study with a rural entrepreneur that uses daydreaming as her main strategic tool in the development of her farm, and a reading of Bachelard's work on the phenomenology of 'reverie,' we come to understand daydreaming as an embodied act that emerges at the intersection between relational materiality, vertical temporality and aesthetic space. This conceptualization of daydreaming reminds us that rather than focusing on how to make dreams come true, which is the traditional way of relating to dreams in organizational life, there is a need to enable people to dream anew, because that is when new beginnings can be born, and the particular will to act, through daydreaming, can be released.
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| 31. |
- Hornborg, Alf, et al.
(författare)
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Förord: Hemkomstens ekonomi
- 2023
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Ingår i: Hemkomstens ekonomi : Företagande bortom erövring - Företagande bortom erövring. - 9789144175249 ; , s. 6-9
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Bokkapitel (populärvet., debatt m.m.)
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| 32. |
- Kenward, Ben, et al.
(författare)
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Preschoolers Distribute Scarce Resources According to the Moral Valence of Recipients' Previous Actions
- 2011
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Ingår i: Developmental Psychology. - : American Psychological Association (APA). - 0012-1649 .- 1939-0599. ; 47:4, s. 1054-1064
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Tidskriftsartikel (refereegranskat)abstract
- Children aged 3 years and 41/2 years old watched a puppet, struggling to achieve goals, who was helped by a 2nd puppet and violently hindered by a 3rd. The children then distributed wooden biscuits between the helper and hinderer. In Experiment 1, when distributing a small odd number of biscuits, 41/2-year-olds (N = 16) almost always gave more to the helper. Children verbally justified their unequal distributions by reference to the helper's prosocial behavior or the hinderer's antisocial behavior. In Experiment 2, when biscuits were more plentiful, 41/2-year-olds (N = 16) usually gave equal numbers to helper and hinderer, indicating that 41/2-year-olds usually preferred not to distribute unequally unless forced to by resource scarcity. Three-year-olds (N = 16 in Experiment 1, N = 20 in Experiment 3) gave more biscuits equally often to the helper and to the hinderer. In many cases, this was because they were confused as to the identities and actions of the puppets, possibly because they were shocked by the hinderer's actions. Two fundamental moral behaviors are therefore demonstrated in young preschoolers: indirect reciprocity of morally valenced acts and a preference for equality when distributing resources, although the cognitive bases for these behaviors remain unclear. These results join other recent studies in demonstrating that the seeds of complex moral understanding and behavior are found early in development.
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| 33. |
- Rörby, Emma, et al.
(författare)
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The stem cell regulator PEDF is dispensable for maintenance and function of hematopoietic stem cells
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- Pigment epithelium derived factor (PEDF), a ubiquitously expressed 50 kDa secreted glycoprotein, was recently discovered to regulate self-renewal of neural stem cells and have a supportive effect on human embryonic stem cell growth. Here, we analyzed expression of PEDF in the murine hematopoietic stem cell (HSC) compartments and found that PEDF is highly expressed in primary long-term HSCs. Therefore, we characterized the hematopoietic system in a knockout mouse model for PEDF and using this model we surprisingly found that PEDF is dispensable for HSC regulation. PEDF knockout mice exhibit normal hematopoiesis in steady state conditions and the absence of PEDF lead to normal regeneration capacity in a serial competitive transplantation setting. Additionally, PEDF-deficient cells exhibit unaltered lineage distribution upon serial transplantations. When human cord blood stem and progenitor cells were cultured in media supplemented with recombinant PEDF they did not show changes in growth potential. Taken together, we report that PEDF is not a critical regulatory factor for HSC function during regeneration in vivo or growth of human stem/progenitor cells in vitro.
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| 34. |
- Sandberg, Margareta, 1947-, et al.
(författare)
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Blood flow changes in the trapezius muscle and overlying skin following transcutaneous electrical nerve stimulation
- 2007
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Ingår i: Physical Therapy. - : Oxford University Press (OUP). - 0031-9023 .- 1538-6724. ; 87:8, s. 1047-1055
-
Tidskriftsartikel (refereegranskat)abstract
- Background and Purpose: Various researchers have studied the effects of transcutaneous electrical nerve stimulation (TENS) on hemodynamics. The purpose of this study was to examine the effects of TENS on local blood flow in the trapezius muscle and overlying skin. Subjects: Thirty-three women who were healthy, aged 25 to 55 years, were randomly assigned to receive 1 of 3 different modes of TENS. Methods: Skin and muscle blood flow were monitored noninvasively using a new application of photoplethysmography for 15 minutes of TENS applied at high frequency (80 Hz) and sensory-level intensity and at low frequency (2 Hz) and motor-level intensity and for 15 minutes after stimulation. Subliminal 80-Hz TENS was used as a control. Blood flow was monitored simultaneously on stimulated and nonstimulated shoulders. Results: Blood flow in the trapezius muscle, but not skin blood flow, increased significantly with motor-level 2-Hz TENS, whereas no increase occurred with sensory-level 80-Hz TENS or subliminal 80-Hz TENS. Discussion and Conclusion: Muscle contractions induced by motor-level 2-Hz TENS appear to be a prerequisite for increasing blood flow in the trapezius muscle. However, high stimulation intensity may prevent increased blood flow in the overlying skin.
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| 35. |
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