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  • 301.
    Adenling, Elinor
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Liljeström, Monica
    Umeå University, Faculty of Social Sciences, Department of Education.
    Studentpresentationer i pedagogik2018In: Digitalisering av högre utbildning / [ed] Stefan Hrastinski, Lund: Studentlitteratur AB, 2018, p. 95-98Chapter in book (Other academic)
  • 302.
    Adenling, Elinor
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Olsson, Johanna
    Umeå University, Faculty of Social Sciences, Department of Education.
    Att mötas utan att mötas: Portfolios som pedagogiskt verktyg i nätbaserad utbildning2010In: Undervisning på tvären, Student- och lärarerfarenheter / [ed] Universitetspedagogiskt Centrum, Umeå universitet, Umeå: Universitetspedagogiskt Centrum, Umeå universitet , 2010, p. 11-28Conference paper (Refereed)
  • 303.
    Adenling, Elinor
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Olsson, Johanna
    Umeå University, Faculty of Social Sciences, Department of Education.
    Erfarenheter av portfoliometodiken inom nätutbildning: Kritiska reflektioner och ”halleluja moments”2011In: Högre Utbildning, ISSN 2000-7558, E-ISSN 2000-7558, Vol. 1, no 2, p. 77-87Article in journal (Refereed)
    Abstract [sv]

    Vid Pedagogiska institutionen vid Umeå universitet har nätutbildningen expanderat kraftigt under de senaste två och ett halvt åren, då institutionen började ge fristående helfartskurser i pedagogik via Internet. Vårterminen 2008 läste cirka 60 studenter och inför varje termin har sedan studenttillströmningen ökat, för att under våren 2010 uppgå till 240 studenter. Hösten 2008 infördes, med stöd av interna utvecklingsmedel, examinerande portfoliouppgifter på samtliga nätbaserade kurser med målsättningen att möta de utmaningar som både formen (nätundervisning) och den utökade och heterogena studentgruppen innebar. Syftet var att stärka studenternas förmåga att synliggöra sitt eget lärande, samt att minska anonymiteten mellan lärare och student. Uppgifterna var av självreflekterande karaktär där studenterna uppmanades att relatera det egna lärandet till kursinnehållet och att exempelvis identifiera framtida tillämpningsområden inom studier och arbetsliv. Studenterna fick under terminen individuell återkoppling av en och samma lärare. Intentionen med återkopplingen var bland annat att guida och uppmuntra studenterna till att inta ett personligt förhållningssätt till kursinnehållet. I artikeln argumenteras det för att portfoliometodik i flera avseenden kan sägas harmoniera väl med ett rådande synsätt på examination där ett sociokulturellt synsätt på lärande dominerar och livslångt lärande och självständighet framhålls som eftersträvansvärt. Detta medför att, det både utifrån ett student- och ett lärarperspektiv, kan kännas naturlig och relevant att använda portfolio som examinationsform inom nätutbildning. Samtidigt är det viktigt att problematisera och kritiskt reflektera över portfoliometodik som examinationsform och de förhållningssätt och ideal som skapas, vilket görs i artikeln med hjälp av en Foucaultinspirerad tolkningsram. I artikeln presenteras alltså både ett kritiskt perspektiv, men även de många ”halleluja moments” som arbetet med portfoliouppgifter inneburit för medverkande lärare och institutionen i stort. Erfarenheterna visar att arbetet med portfolio som examinationsform är dubbelbottnat: Å ena sidan kan det exempelvis bidra till en stärkt språklig kompetens och personlig utveckling hos studenterna. Å andra sidan kan portfoliometodik sägas leda till en ökad kontroll och självdisciplinering som sträcker sig bortom själva examinationstillfället.

  • 304.
    Ader, Ulla
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Psychotherapy.
    Lundblad Danielsson, Inga
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Psychotherapy.
    Att lyssna till tonårsröster: Psykisk hälsa hos ungdomar med funktionsnedsättning2012Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med fördjupningsarbetet har varit att via en pilotstudie öka kunskapen om ungdomar med funktionsnedsättning i Umeå, med avseende på psykisk hälsa, och på hur de upplever sin vardag i skolan, med kamrater och i familjen. Psykisk hälsa undersöktes genom att ungdomar med funktionsnedsättning som går i specialklasser (grundsärskolans högstadium, högstadium för ungdomar med Asperger, högstadium för ungdomar med rörelsenedsättningar), fick besvara en enkät under skoltid. För att kunna relatera till den undersökning som Statens Folkhälsoinstitut genomförde hos ungdomar i Sverige 2009 har samma enkät använts.

     

    Resultatet visar att de flesta ungdomar har angett att de mår bra, trivs i skolan, har bra kontakt med sina lärare och med sina föräldrar. Majoriteten mår lika bra som de flesta ungdomar i landet och t.om bättre än de ungdomar i Folkhälsoinstitutets undersökning, som angett att de hade någon funktionsnedsättning.

     

    Inom några områden visades dock lägre resultat. Ungdomarna i vår undersökning uppgav att deras svårigheter påverkade deras vardag i familjen och vid fritidsaktiviteter. De umgås mer sällan med kamrater, motionerar mindre och har färre fritidsaktiviteter. Ungdomar med Asperger skiljer ut sig mest i vår undersökning, de är mindre nöjda med livet och med sig själva, känner sig mer ensamma,  umgås mer sällan med kamrater och har mindre kul, jämfört med ungdomar i grundsärskolan.

     

    Det finns områden där stödet ifrån Barn- och ungdomshabiliteringen kan förbättras, som att utveckla metoder för socialt samspel och stärka ungdomarnas identitet och i samarbete med andra aktörer öka delaktigheten till en mer aktiv fritid.

  • 305.
    Adere, Endale
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE).
    Accounting for Oil and Gas: The effect of the gap between US GAAP and IFRS on Norwegian companies2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Background

    Oil and gas is a main source of revenue for many countries. Norway is one of them. Several companies operate in these countries. The companies demand accounting to communicate to their stakeholders. The two biggest accounting regimes, IASB and USA have their own standards for the upstream activities of those companies. The standard setting bodies mandatorily require companies to comply. Norwegian listed companies, as they are in the IASB regime, must comply with the IASB standard, IFRS 6.

    Problem 

    The IASB standard has a problem of addressing the entire upstream activities of the companies Moreover, the standard has conceptual flaw. However, these oil and gas firms are required to follow it. As a remedy, the entities fill the gap by using the US GAAP, if they are listed, as the regulation requires them to follow IFRS. Thus, using these two standards coupled with the defect of the IASB standard is affecting them.

    Purpose

    The purpose of this thesis is to explain the effects of IFRS 6 on companies by comparing it with the US GAAP standard. In doing so, theories relevant to the issue are described and the technical gaps between the two standards are elaborated.

    Method 

    This thesis uses mixed method. The research design followed is concurrently mixing quantitative and qualitative methods. However, qualitative method dominates in the mixing. As a data collection mechanism, interview, questionnaire and documentation i.e. the annual reports of the companies are used. In the study both deductive and inductive reasoning are used.

    Conclusion

    Subsequent to making the study, the author concludes that the surveyed companies have used the US GAAP to fill the gap that IFRS possess. However, retaining two sets of accounts has economic effect and the companies are paying for that. Moreover, they expend costs for adopting the IFRS when they change their standard from US GAAP to IFRS. Moreover, it is difficult to make conclusion about diffusion of accounting method due to contagion effect. Similarly, although previous studies show that size of a firm is a determinant factor, it is tricky to make conclusion on the studied companies.

  • 306. Aderud, Johan
    Användbarhetsstudie av Nätuniversitetets webbportal: en uppföljning 20052006Report (Other academic)
  • 307.
    Adestam, Martin
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Husberg, Susanne
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    ESG Implementation in Venture Capital Investments: A qualitative study of Swedish State-owned Investors2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The need for sustainable investments has grown dramatically in recent years and so has the pressure on investors, especially state-owned investors, to integrate sustainability factors in their investments. Several researchers state that private equity investors play a major role in creating new businesses and influencing new companies towards sustainability. On the Swedish private equity market, a major part of the funds available to growth companies are provided by the Government. State-owned investor’s role to create sustainable businesses in Sweden is therefore essential. However, research on how to implement ESG issues into venture capital investments is rare. Still today, we could not find any reports on how ESG issues are implemented by Swedish state-owned investors.

    An empirical study was conducted on four major Swedish state-owned investors with the purpose to answer how state-owned investors implement ESG issues in venture capital investments. The study also aimed to identify problems with implementing ESG and how can state-owned investors work to deal with these problems.

    Interviews with investment managers and people working within these organization showed that it is generally up to each investor how ESG issues are being considered in the due diligence and screening process within direct investments. When it comes to post-investment activities the responsibility to work with ESG issues lays upon the board of each firm.

    The study further showed that little is being done to implement ESG issues within indirect investments. The study shows that ESG issues are not included in the valuation of general partner or as criteria for investing in a fund or other partnerships. A final conclusion is that when it comes to how state-owned investors are working with venture capital investments, ESG issues are integrated in how investors think, but it is not implemented in how investors act.

    In order to move from integration to implementation we suggest that investors could use a set of templates in the screening and due diligence process. Every template should be specific for the sector that includes the type of ESG criteria that is relevant for this sector. When it comes to indirect investments, the implementation of ESG issues is harder due to limited possibility to actively directing funds. The focus should be working with co-investors with the same values and beliefs and influence the board of the fund.

  • 308.
    Adestam, Martin
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Rosenberg, Lars
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Vikten av en finansiell strategi under en finansiell kris: - En kvantitativ studie av svenska publika aktiebolag2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien utfördes mot bakgrund av hur den globala finanskrisen, som startade i USA under 2007, påverkade svenska företag. Syftet med studien var att undersöka om svenska företag kan påverka hur de klarar en finansiell kris genom att arbeta med komponenter i den finansiella strategin. En kvantitativ undersökning genomfördes på 59 svenska publika aktiebolag där samband testades mellan riskrelaterade variabler ur den finansiella strategin och variabler som mäter hur företag klarat sig under krisåret 2008. I undersökningen testades soliditet, likviditet, kassalikviditet, andel finansiella tillgångar och andel lager, som delar ur den finansiella strategin. Studien visar att kapitalstrukturhantering, kapitalbudgetering (i form av andel finansiella tillgångar) och rörelsekapitalhantering är alla delar ur den finansiella strategin som visats betydande. Kapitalstrukturhanteringen ska karaktäriseras av låg skuldsättning och kapitalbudgeteringen av låg andel finansiella tillgångar, för att skapa en finansiell strategi som ger företag bättre förutsättningar i en finansiell kris. Kontrollen av rörelsekapital i rörelsekapitalhanteringen är också en betydande del i en sådan strategi, även om inga tydliga riktlinjer gällande nivåer på rörelsekapitalet kan härledas från studien.

  • 309.
    Adhikari, Deepak
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Signaling pathways in the development of female germ cells2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Primordial follicles are the first small follicles to appear in the mammalian ovary. Women are born with a fixed number of primordial follicles in the ovaries. Once formed, the pool of primordial follicles serves as a source of developing follicles and oocytes. The first aim of this thesis was to investigate the functional role of the intra-oocyte signaling pathways, especially the phosphatidylinositol-3 kinase (PI3K) and mammalian target of rapamycin complex 1 (mTORC1) pathways in the regulation of primordial follicle activation and survival. We found that a primordial follicle remains dormant when the PI3K and mTORC1 signaling in its oocyte is activated to an appropriate level, which is just sufficient to maintain its survival, but not sufficient for its growth initiation. Hyperactivation of either of these signaling pathways causes global activation of the entire pool of primordial follicles leading to the exhaustion of all the follicles in young adulthood in mice. Mammalian oocytes, while growing within the follicles, remain arrested at prophase I of meiosis. Oocytes within the fully-grown antral follicles resume meiosis upon a preovulatory surge of leutinizing hormone (LH), which indicates that LH mediates the resumption of meiosis. The prophase I arrest in the follicle-enclosed oocyte is the result of low maturation promoting factor (MPF) activity, and resumption of meiosis upon the arrival of hormonal signals is mediated by activation of MPF. MPF is a complex of cyclin dependent kinase 1 (Cdk1) and cyclin B1, which is essential and sufficient for entry into mitosis. Although much of the mitotic cell cycle machinery is shared during meiosis, lack of Cdk2  in mice leads to a postnatal loss of all oocytes, indicating that Cdk2 is important for oocyte survival, and probably oocyte meiosis also. There have been conflicting results earlier about the role of Cdk2 in metaphase II arrest of Xenopus  oocytes. Thus the second aim of the thesis was to identify the specific Cdk that is essential for mouse oocyte meiotic maturation. We generated mouse models with oocytespecific deletion of Cdk1  or Cdk2  and studied the specific requirements of Cdk1 and Cdk2 during resumption of oocyte meiosis. We found that only Cdk1 is essential and sufficient for the oocyte meiotic maturation. Cdk1 does not only phosphorylate the meiotic phosphoproteins during meiosis resumption but also phosphorylates and suppresses the downstream protein phosphatase 1, which is essential for protecting the Cdk1 substrates from dephosphorylation.

  • 310.
    Adhikari, Deepak
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Flohr, Gilian
    Hogeschool Leiden, Zernikedreef 11,2333 CK Leiden, The Netherlands.
    Gorre, Nagaraju
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Shen, Yan
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Yang, Hairu
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Lundin, Eva
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Lan, Zijian
    University of Louisville Health Sciences Center, Louisville, Kentucky, USA.
    Liu, Kui
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Disruption of Tsc2 in oocytes leads to overactivation of the entire pool of primordial follicles2009In: Molecular human reproduction, ISSN 1360-9947, E-ISSN 1460-2407, Vol. 15, no 12, p. 765-770Article in journal (Refereed)
    Abstract [en]

    To maintain the length of reproductive life in a woman, it is essential that most of her ovarian primordial follicles are maintained in a quiescent state to provide a continuous supply of oocytes. However, our understanding of the molecular mechanisms that control the quiescence and activation of primordial follicles is still in its infancy. In this study, we provide some genetic evidence to show that the tumor suppressor tuberous sclerosis complex 2 (Tsc2), which negatively regulates mammalian target of rapamycin complex 1 (mTORC1), functions in oocytes to maintain the dormancy of primordial follicles. In mutant mice lacking the Tsc2 gene in oocytes, the pool of primordial follicles is activated prematurely due to elevated mTORC1 activity in oocytes. This results in depletion of follicles in early adulthood, causing premature ovarian failure (POF). Our results suggest that the Tsc1-Tsc2 complex mediated suppression of mTORC1 activity is indispensable for maintenance of the dormancy of primordial follicles, thus preserving the follicular pool, and that mTORC1 activity in oocytes promotes follicular activation. Our results also indicate that deregulation of Tsc/mTOR signaling in oocytes may cause pathological conditions of the ovary such as infertility and POF.

  • 311.
    Adhikari, Deepak
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Liu, Kui
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Molecular mechanisms underlying the activation of mammalian primordial follicles2009In: Endocrine reviews, ISSN 0163-769X, E-ISSN 1945-7189, Vol. 30, no 5, p. 438-464Article in journal (Refereed)
    Abstract [en]

    In humans and other mammalian species, the pool of resting primordial follicles serves as the source of developing follicles and fertilizable ova for the entire length of female reproductive life. One question that has intrigued biologists is: what are the mechanisms controlling the activation of dormant primordial follicles. Studies from previous decades have laid a solid, but yet incomplete, foundation. In recent years, molecular mechanisms underlying follicular activation have become more evident, mainly through the use of genetically modified mouse models. As hypothesized in the 1990s, the pool of primordial follicles is now known to be maintained in a dormant state by various forms of inhibitory machinery, which are provided by several inhibitory signals and molecules. Several recently reported mutant mouse models have shown that a synergistic and coordinated suppression of follicular activation provided by multiple inhibitory molecules is necessary to preserve the dormant follicular pool. Loss of function of any of the inhibitory molecules for follicular activation, including PTEN (phosphatase and tensin homolog deleted on chromosome 10), Foxo3a, p27, and Foxl2, leads to premature and irreversible activation of the primordial follicle pool. Such global activation of the primordial follicle pool leads to the exhaustion of the resting follicle reserve, resulting in premature ovarian failure in mice. In this review, we summarize both historical and recent results on mammalian primordial follicular activation and focus on the up-to-date knowledge of molecular networks controlling this important physiological event. We believe that information obtained from mutant mouse models may also reflect the molecular machinery responsible for follicular activation in humans. These advances may provide a better understanding of human ovarian physiology and pathophysiology for future clinical applications.

  • 312.
    Adhikari, Deepak
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Liu, Kui
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    mTOR signaling in the control of activation of primordial follicles2010In: Cell Cycle, ISSN 1538-4101, E-ISSN 1551-4005, Vol. 9, no 9, p. 1673-1674Article in journal (Refereed)
  • 313.
    Adhikari, Deepak
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Zheng, Wenjing
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Shen, Yan
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gorre, Nagaraju
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Hämäläinen, Tuula
    Cooney, Austin J
    Huhtaniemi, Ilpo
    Lan, Zi-Jian
    Liu, Kui
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Tsc/mTORC1 signaling in oocytes governs the quiescence and activation of primordial follicles2010In: Human Molecular Genetics, ISSN 0964-6906, E-ISSN 1460-2083, Vol. 19, no 3, p. 397-410Article in journal (Refereed)
    Abstract [en]

    To maintain the female reproductive lifespan, the majority of ovarian primordial follicles are preserved in a quiescent state in order to provide ova for later reproductive life. However, the molecular mechanism that maintains the long quiescence of primordial follicles is poorly understood. Here we provide genetic evidence to show that the tumor suppressor tuberous sclerosis complex 1 (Tsc1), which negatively regulates mammalian target of rapamycin complex 1 (mTORC1), functions in oocytes to maintain the quiescence of primordial follicles. In mutant mice lacking the Tsc1 gene in oocytes, the entire pool of primordial follicles is activated prematurely due to elevated mTORC1 activity in the oocyte, ending up with follicular depletion in early adulthood and causing premature ovarian failure (POF). We further show that maintenance of the quiescence of primordial follicles requires synergistic, collaborative functioning of both Tsc and PTEN (phosphatase and tensin homolog deleted on chromosome 10) and that these two molecules suppress follicular activation through distinct ways. Our results suggest that Tsc/mTORC1 signaling and PTEN/PI3K (phosphatidylinositol 3 kinase) signaling synergistically regulate the dormancy and activation of primordial follicles, and together ensure the proper length of female reproductive life. Deregulation of these signaling pathways in oocytes results in pathological conditions of the ovary, including POF and infertility.

  • 314.
    Adhikari, Deepak
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Zheng, Wenjing
    Univ Gothenburg, Dept Chem & Mol Biol, SE-40530 Gothenburg, Sweden.
    Shen, Yan
    Univ Gothenburg, Dept Chem & Mol Biol, SE-40530 Gothenburg, Sweden.
    Gorre, Nagaraju
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ning, Yao
    Univ Gothenburg, Dept Chem & Mol Biol, SE-40530 Gothenburg, Sweden.
    Halet, Guillaume
    Univ Rennes 1, CNRS, UMR 6061, Inst Genet & Dev Rennes, F-35043 Rennes, France .
    Kaldis, Philipp
    NUS, A STAR, IMCB, Singapore 138673, Singapore.
    Liu, Kui
    Univ Gothenburg, Dept Chem & Mol Biol, SE-40530 Gothenburg, Sweden.
    Cdk1, but not Cdk2, is the sole Cdk that is essential and sufficient to drive resumption of meiosis in mouse oocytes2012In: Human Molecular Genetics, ISSN 0964-6906, E-ISSN 1460-2083, Vol. 21, no 11, p. 2476-2484Article in journal (Refereed)
    Abstract [en]

    Mammalian oocytes are arrested at the prophase of meiosis I during fetal or postnatal development, and the meiosis is resumed by the preovulatory surge of luteinizing hormone. The in vivo functional roles of cyclin-dependent kinases (Cdks) during the resumption of meiosis in mammalian oocytes are largely unknown. Previous studies have shown that deletions of Cdk3, Cdk4 or Cdk6 in mice result in viable animals with normal oocyte maturation, indicating that these Cdks are not essential for the meiotic maturation of oocytes. In addition, conventional knockout of Cdk1 and Cdk2 leads to embryonic lethality and postnatal follicular depletion, respectively, making it impossible to study the functions of Cdk1 and Cdk2 in oocyte meiosis. In this study, we generated conditional knockout mice with oocyte-specific deletions of Cdk1 and Cdk2. We showed that the lack of Cdk1, but not of Cdk2, leads to female infertility due to a failure of the resumption of meiosis in the oocyte. Re-introduction of Cdk1 mRNA into Cdk1-null oocytes largely resumed meiosis. Thus, Cdk1 is the sole Cdk that is essential and sufficient to drive resumption of meiosis in mouse oocytes. We also found that Cdk1 maintains the phosphorylation status of protein phosphatase 1 and lamin A/C in oocytes in order for meiosis resumption to occur.

  • 315. Adhikary, N C
    et al.
    Misra, Amar P
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Bailung, H
    Chutia, J
    Ion-beam driven dust ion-acoustic solitary waves in dusty plasmas2010In: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 17, no 4, article id 044502Article in journal (Refereed)
    Abstract [en]

    The nonlinear propagation of small but finite amplitude dust ion-acoustic waves (DIAWs) in an ion-beam driven plasma consisting of Boltzmannian electrons, positive ions, and stationary negatively charged dust grains is studied by using the standard reductive perturbation technique. It is shown that there exist two critical values (γc1) and (γc2) of ion beam to ion phase velocity ratio (γ), above and below which the beam generated solitons are not possible. The effects of the parameters, namely, γ, the ratio of the ion beam to plasma ion density (μi), the dust to ion density ratio (μd), and the ion beam to plasma ion mass ratio (μ) on both the amplitude and width of the stationary DIAWs, are analyzed numerically, and applications of the results to laboratory ion beam as well as space plasmas (e.g., auroral plasmas) are explained.

  • 316.
    Adielsson, Peter
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Sjöström, Johan
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    HR-funktionens strategiska roll: En kvalitativ studie i uppfattningen om HR-funktionens värdeskapande2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    HR är ett ämnesområde som traditionellt fått mycket uppmärksamhet inom akademisk forskning där fokus varit på HR som stödjande funktion i form av personalförsörjning. I början av 1990-talet bildades en ny forskningsinriktning som berör HR som en strategiskt viktigt affärsenhet och i takt med den ökade konkurrensen på den Svenska arbetsmarknaden har HR blivit en mer prioriterad funktion för företag. Vi har valt att utifrån ett företagsekonomiskt perspektiv applicera teorier kring strategisk HR, arbetsgivarvarumärke samt talanghantering på svenska organisationer. Tidigare forskning har främst haft fokus på att enbart undersöka HR-avdelningen. Således har vi i den här studien försökt skapa en förståelse för om det finns en skillnad i uppfattningen av HR-funktionen som värdeskapande genom att intervjua specialister samt generalister. Historiskt finns det en problematik i att HR-funktionen enligt tidigare forskning haft svårt att synliggöra värdeskapande då den ofta ses som en ren stödjande funktion. Genom att undersöka Svenska företag inom flera olika branscher, och som uttalat arbetar strategiskt med HR är syftet med studien att undersöka om det finns en skillnad i uppfattningen av HR-funktionens värdeskapande mellan personer som arbetar med HR som generalister gentemot personer som är specialister. Vidare vill vi genom att undersöka hur organisationers strategiska arbete skiljer sig med fokus på strategisk HRM, talanghantering samt arbetsgivarvarumärke öka kunskapsbildningen inom det vetenskapliga ämnesområdet.

     

    Den övergripande slutsatsen i studien är att den interna kommunikationen mellan specialister och generalister bör förbättras för att synliggöra HR-funktionens värdeskapande roll. Med en tydligare kommunikation kommer även det strategiska arbetet med arbetsgivarvarumärket och talanghantering förbättras. Även utvärdering av strategierna har visat sig vara en central faktor för att öka förståelsen för vilket värdeskapande strategierna ger. Utvärdering blir således ett viktigt verktyg för HR-specialister att skapa större uppskattning av funktionen. 

     

     

     

     

     

  • 317.
    Aditya, Pawar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Composing the Umeå pantry: a platform for dialogue on food production and human survival2015In: Participatory Innovation Conference, PIN-C / [ed] Rianne Valkenburg, Coen Dekkers, Janneke Sluijs, The Hague, 2015, Vol. 1, p. 83-90Conference paper (Refereed)
    Abstract [en]

    The Umeå Pantry was a five-week long public art event held in Umeå, Sweden, aimed at making concerns about food production public and supporting local communities interested in food related practices.

    The event consisted of a series of performances where participant communities were invited to a dialogue on food concerns and practices in the region. The performances took the form of communal activities such as food harvesting, cooking, workshops, debates and demonstrations.

    The making of the art event highlights the practice of creating forms for engagement and participation of disparate communities around social issues.

    In the broader picture, this project contributes to the understanding of community participatory design and design for social innovation.

  • 318.
    Aditya, Pawar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Open-collaborative libraries: Libraries as generative community centres2015Conference paper (Other (popular science, discussion, etc.))
  • 319.
    Aditya, Pawar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Prototyping boundary objects: Boundary objects as means for negotiating a cultural imaginary2015Conference paper (Other academic)
  • 320.
    Aditya, Pawar
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    The Ability To Make A Difference In Participatory Design Projects2017Conference paper (Refereed)
    Abstract [en]

    The case study presented here is an intensive nine day community participation project in a Swiss town, aimed at fostering community food production. The approach to participatory design presented here seeks to emphasize the in-situ improvisatory ‘doing' of collaborative activities.

    Using notions such as diffusing, reifying and catalyzing the study describes the iterative movement of the project that is bound up in material arrangements and social relations.

    Through a reflection in action approach, the author unpacks how the designer's agency is understood through social interactions and acts of summarizing, materialization and translation.

    The paper concludes by discussing power and agency, both as an outcome and central to the design process. This reflective exploration through the lens of agency seeks to encourage the reflexivity of designers in collaborative practice.

  • 321.
    Adjei, Daniel
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Rwakatiwana, Peter
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Application of Traditional and Agile Project Management in Consulting Firms.: A Case Study of PricewaterhouseCoopers2010Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    AbstractPurposeTo study which and how project management methodologies are applied in consulting firmsApproachThe study begins by reviewing literature on Traditional Project Management (TPM) andAgile Project Management (APM) methodologies ending with characteristics of the twomethodologies that identify a project as applying one methodology or another. The literaturethen reviews the nature of consulting firms emphasising on elements such as the professional,professional services and professional service firms before reviewing how projects areimplemented in consulting firms. A case study design is adopted and semi-structuredinterviews were conducted with PricewaterhouseCoopers-Ghana staff. Patterns from theinterviews are identified and compared with the characteristics of both Traditional and Agileproject management before drawing conclusions on which methodologies are applied andhow they are applied. Since APM is presumed to deal with problems of TPM in complexenvironments, challenges in applying TPM in consulting firms are assessed and the extent towhich APM responds to those challenges are also discussed.FindingsThe findings indicate that TPM is applied in consulting firms mainly for structured projects,whilst APM methods are also applied for some structured projects but very much forunstructured and ‘executory’ projects. APM also deals with some challenges of TPM butthose which are organisation related are not solved by applying APM methods.Research limitationThe limited number of people interviewed for this research is one key issue that limitsgeneralization to all consulting firms. However, it is hoped that this work serves as a basis forfurther research in this field.Practical implicationsThe study shows that whilst TPM will continuously be applied in consulting firms due to thenature of some projects, APM can also be applied to the benefit of consulting projects that areunstructured and ‘executory’. Therefore consulting firms do not need to ‘force’ structure intoall projects.Paper typeMasters Thesis – Research paperKeywordsTraditional project management, agile project management, consulting firms, professional,professional service, professional service firms

  • 322.
    Adjei, Evans
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Family firm and entrepreneurial capital: the importance of entrepreneurial capital for firm survival and growthManuscript (preprint) (Other academic)
    Abstract [en]

    We examined the effects of current (family firms) and past family relations (entrepreneurial capital (EC) -inherited entrepreneurial practices from self-employed parents)on the survival and growth of new entrants, taking into account the regional context and the effects of the 2008 global financial crisis. Moreover, we examined whether familial relations also contribute to job creation. The guiding assumption is that the role of familial relations for start-ups is of primary importance for spatial variations of economic development. Using start-ups with a maximum of 50 employees in 2002 in Sweden, we followed each firm until the firm exited. The results indicate that the resilience of family firms is confounded by EC. Hence, it is not family firms per se that are more resilient but rather firms with entrepreneurial experience from self-employed parents; however, it is family firms that create more jobs. The results further indicate that the impacts of EC are predominantly found in rural regions. The analyses suggest that family firms and EC explain different aspects of the local economic development, which is a finding important for policy-making.

  • 323.
    Adjei, Evans
    et al.
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Eriksson, Rikard
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Lindgren, Urban
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Social proximity and firm performance: the importance of family member ties in workplaces2016In: Regional Studies, Regional Science, ISSN 0080-0694, E-ISSN 2168-1376, Vol. 3, no 1, p. 303-319Article in journal (Refereed)
    Abstract [en]

    This study empirically assesses the role of social proximity, defined as the concentration of family members (FM) in firms, on firm performance. Based on longitudinal micro-data for the period 1995–2010 connecting information on workers and their workplaces in the Swedish labour market, the effects of FM (parents, children, siblings and grandparents) on per capita productivity in 15,359 firms were analysed. The results indicate that FM positively affect firm performance. In particular, the results suggest that in specialized regions (mainly small regions) FM have a positive influence on performance and can thus compensate for relative shortage of regional agglomeration economies.

  • 324.
    Adjei, Evans
    et al.
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Eriksson, Rikard
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Lindgren, Urban
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Holm, Einar
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Familial relationships and firm performance: the impact of entrepreneurial family relationships2019In: Entrepreneurship and Regional Development, ISSN 0898-5626, E-ISSN 1464-5114, Vol. 31, no 5-6, p. 357-377Article in journal (Refereed)
    Abstract [en]

    While the family may serve as a resource for entrepreneurs, it has been studied separately in different disciplines. In this paper, we combine the arguments on familial relationships (family firm literature) and skill variety (regional learning literature) to analyse how different forms of entrepreneurial family relationships (co-occurrences) facilitate firm performance, and how familial relationships moderate the effects of skill variety on firm performance. Using longitudinal data (2002-2012) on a sample of privately owned firms with up to 50 employees with matched information on all employees, our results show that entrepreneur children relationship is the dominant dyad familial relationship in family firms. The fixed effects estimates demonstrate that entrepreneurial family relationships do affect firm performance but that this is dependent on the type of familial relationship. Children and spouses show a positive relationship with firm performance while siblings of the entrepreneur show no significant relationship with performance. The estimates further indicate that familial relationships involving spouses abate the negative effects of having too similar or too different types of skills. The paper thus contributes to new knowledge regarding not only whether family relationships matter for performance, but also in what way they matter.

  • 325.
    Adjei, Evans Korang
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Relatedness through kinship: the importance of family co-occurrence for firm performance2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim of the thesis is to analyse the effects of family co-occurrence and past familial relationships (inherited entrepreneurial abilities) on firm performance. This aim is motivated by the contemporary arguments that social relations (e.g. family ties) are important in the analysis of today’s space economy. In most studies, the point of departure in the analysis of firm performance has often been to analyse and examine the cognitive resources available in a firm, as well as a firm’s geographical closeness to related firms and industries. However, this argument has been challenged, and it is further suggested that social relations, and for that matter family relations (or family co-occurrence), may be important in the analysis of firm performance. To test this argument, the analysis is based on longitudinal data comprising various register data on the Swedish population and firms.

    To examine the aim, three different but related questions were analysed: the first analysed the prevalence of family employment across different regions and how this affects firm performance; the second examined the relationship between entrepreneurs’ familial relations (co-occurrence of different family relations) and skill variety, on one hand, and how the relationship affects firm performance on the other; and the third examined the effects of present family relations (family firms) and entrepreneurial capital (EC, past family relations) on the survival and growth of new entrants. Questions 1 and 2 were explored by applying simple ordinary least squares (OLS) and fixed effects (FE) regressions, respectively. Question 3 was explored by employing an event-history analysis (survival analysis) to determine the time to exit and OLS for the growth analysis.

    The results show that family co-occurrence in firms (be they family or non-family firms) positively affect labour productivity. At the same time, the results show that some specific family relationships are more important than others in terms of impacting labour productivity. Moreover, the results indicate that family firms, in particular, benefit the most from having family members employed in the firm, especially when this involves family relationships such as couples and/or children. The co-occurrence of couples and/or children in family firms moderates the negative impacts of similarities and unrelatedness of skills on productivity. The results show that the impacts of family co-occurrence are greater in smaller specialized regions than diverse and larger ones. Thus, while the family positively correlates with firm performance, this is mainly the case in specialized regions. The results further show that family firms are not more resilient, as the literature argues; but this effect is confounded by EC. The implication is that it is not family firms per se that are resilient but rather firms with entrepreneurial experience from parents, especially in rural regions; meanwhile, family firms create more jobs. However, the analysis could not identify a clear regional effect of the role of family firm on job creation. In this sense, the present thesis provides important insight into why the family constitutes an important part of the firm production setup. The findings show that it is necessary and important to consider the family, and family firms, in the larger regional development framework. Moreover, while reflecting on the uniqueness of the family as a social group whose shared identity and mutual trust can enhance firm performance and regional development, we should also not lose sight of the fact that there is a latent risk: it is not a problem—until it becomes a problem.

  • 326.
    Adjei Korang, Evans
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History.
    Regional Income differences in Ghana: the importance of socio-demography and ethnicity2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Following the increased attention income differences/inequality has gained within the area of economic geography and among policy-planning; this study seeks to explore and analyze the factors affecting income differences in the regions of Ghana. From the use of regional (10 regions) panel data for 1960, 1970, 1984 and 2000; the results show a direct link between socio-demographic factors and regional income differences/inequality and also the impact of ethnic and religious composition on regional income differences. It was identified that ethnicity and religious compositions have different impacts on regional income differences. Christians have positive effect on regional income due to their fairly representation in almost all the regions likewise the Akans, but have negative effect on regional income. And also high population density in a region reduces the mean regional income, similarly high concentration of population aged 60years and over reduces the regional income. Evidence from the results empirically conclude that regions with high share of aged population, Akans, Muslims and high population density have low regional income compared with regions with high share of Christians. 

  • 327.
    Adjei Korang, Evans
    et al.
    Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Eriksson, Rikard
    Umeå University, Faculty of Social Sciences, Department of Geography. Umeå University, Faculty of Social Sciences, Centre for Regional Science (CERUM).
    Skogen som resurs in Region Västernorrland: näringslivsnalys 2002-20152019Report (Other academic)
    Abstract [sv]

    Med utgångspunkt i perspektivet att ekonomisk utveckling i grund och botten är betingat på de kompetenser som används i produktionen av varor och tjänster, har denna rapport analyserat skogsnäringarnas utveckling i Västernorrland 2002-2015 med avseende på sysselsättning, antal arbetsgivare och arbetsinkomster. Särskilt fokus ligger på hur Västernorrlands skogsindustri är kopplad till övriga delar av näringslivet i form av det humankapital som de delar med varandra. Detta görs empiriskt genom analyser av regionens skill-relatedness, det vill säga flöden av arbetskraft mellan sektorer i regionen, för att grafiskt visa i vilken grad olika sektorer är relaterade till varandra. Utifrån argumentet att humankapital är en central resurs för regional utveckling låter vi data visa hur regionens skogsnäringar är kopplade till övriga näringslivet, och därigenom belysa branschöverskridande relationer bortom gängse föreställningar om kopplingar drivna av det officiella industriklassificeringssystemet. 

    Även om inkomstutvecklingen och andelen kvinnor i Västernorrland följer riksgenomsnittet har både antalet företag och sysselsatta utvecklats betydligt sämre i Västernorrland. Generella utbildningsnivån har ökat både i riket och i regionen, men Västernorrland har generellt en lägre utbildningsnivå. Skogsnäringarna i Västernorrland bryter delvis mot detta generella regionala mönster. Både antalet sysselsatta och antalet arbetsställen inom skogsnäringarna har kraftigt minskat i antal och tvärtemot regionens generella utveckling har också andelen högutbildade (med minst treårig universitetsexamen) minskat liksom andelen kvinnor. Trots dessa kraftiga rationaliseringar på personalsidan är utvecklingen för skogsnäringarna inom Västernorrland betydligt mindre negativ än för riket i övrigt. Det gäller framförallt inkomstnivåerna bland de anställda. Inkomstnivåerna i Sveriges skogsnäring har sjunkit i relativa termer men ökat med drygt 20% i Västernorrland och ligger 2015 på en något högre nivå än övriga näringar i regionen. Det kan i sin tur tyda på en positiv omvandling mot mer kvalificerade arbetstillfällen, även om det också inneburit kraftiga rationaliseringar. 

    För att belysa hur skogsnäringarna är inbäddade i regionens struktur av kompetenser har vi kartlagt graden av specialisering (hur representerad en industri är i regionen relativ i riket), graden av relatedness(hur väl en industri är kopplad till andra industrier genom personalflöden), och graden av inbäddning (förekomsten av andra industrier i regionen som delar liknande kompetensresurser). När det gäller den relativa närvaron av skogsnäringar i regionen utifrån antalet sysselsatta finner vi att ingen av skogsnäringarna har en betydande relativ specialisering i Västernorrland. Det är endast tillverkning av wellpapp och pappers- och pappförpackningar som har en specialiseringsgrad över 1 (dvs högre än riksgenomsnittet). Det innebär med andra ord att trots ett relativt högt bidrag till regionalt förädlingsvärde och skatter är näringarna underrepresenterade på regionens arbetsmarknad. Det återspeglas bland annat i den relativt kraftiga minskningen av sysselsatta och arbetsställen vi identifierat (och som pågått långt innan den period denna rapport analyserar) men också den relativt kraftiga ökningen av inkomster (högre än riksgenomsnittet för skogsnäringarna och i paritet med regionen i övrigt). Skogsnäringarna har med andra ord genomfört produktivitetshöjande rationaliseringar vilket i sig kan gynna regionen.

    Utifrån vårt analytiska ramverk är det dock aningen mer problematiskt att de relativt få arbetsgivarna inom skogsnäringarna också är relativt isolerade i regionen utifrån ett kompetensresursperspektiv. Det är endast tillverkning av andra byggnads- och inredningssnickerier, skogsförvaltning, drivning och pappers- och papptillverkning som har en genomsnittlig koppling till andra näringar i regionen över gränsvärdet för en kompetensrelaterad verksamhet. Detta återspeglas också i hur inbäddad skogsnäringen är utifrån den relativa koncentrationen av kompetensrelaterade verksamheter. Det är endast ovan nämnda fyra näringar som är tydligt inbäddade i regionens näringslivsstruktur, och endast två (pappers- och papptillverkning och tillverkning av byggnads- och inredningssnickerier) som har ett inbäddningsindex över regionens medelvärde. Det innebär att skogsnäringarna generellt är relativt perifera när vi pratar om vilka kompetensresurser skogsnäringen delar med övriga regionen. Dock är teknisk konsultverksamhet direkt eller indirekt relaterat till flertalet skogsnäringar, vilket kan peka på ökade tekniknivåer och ökat behov av tekniska specialistkunskaper. Även om företag kan kompensera för en svag regional inbäddning genom utomregionala nätverk, innebär framförallt en svag inbäddning att det kan vara svårare för arbetskraften att finna nya produktiva uttryck för sina kompetenser i regionen vid framtida rationaliseringar. Det i sin tur kan driva på utflyttning till andra regioner.

    Utifrån en smart specialiseringsagenda drar vi slutsatsen att policyinsatser bör verka för att öka graden av inbäddning för regionens nyckelindustrier då det kan underlätta en framgångsrik omvandling som bygger på regionens redan existerande kompetensresurser. 

  • 328.
    Adjeiwaah, Mary
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Quality assurance for magnetic resonance imaging (MRI) in radiotherapy2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Magnetic resonance imaging (MRI) utilizes the magnetic properties of tissues to generate image-forming signals. MRI has exquisite soft-tissue contrast and since tumors are mainly soft-tissues, it offers improved delineation of the target volume and nearby organs at risk. The proposed Magnetic Resonance-only Radiotherapy (MR-only RT) work flow allows for the use of MRI as the sole imaging modality in the radiotherapy (RT) treatment planning of cancer. There are, however, issues with geometric distortions inherent with MR image acquisition processes. These distortions result from imperfections in the main magnetic field, nonlinear gradients, as well as field disturbances introduced by the imaged object. In this thesis, we quantified the effect of system related and patient-induced susceptibility geometric distortions on dose distributions for prostate as well as head and neck cancers. Methods to mitigate these distortions were also studied.

    In Study I, mean worst system related residual distortions of 3.19, 2.52 and 2.08 mm at bandwidths (BW) of 122, 244 and 488 Hz/pixel up to a radial distance of 25 cm from a 3T PET/MR scanner was measured with a large field of view (FoV) phantom. Subsequently, we estimated maximum shifts of 5.8, 2.9 and 1.5 mm due to patient-induced susceptibility distortions. VMAT-optimized treatment plans initially performed on distorted CT (dCT) images and recalculated on real CT datasets resulted in a dose difference of less than 0.5%.

     The magnetic susceptibility differences at tissue-metallic,-air and -bone interfaces result in local B0 magnetic field inhomogeneities. The distortion shifts caused by these field inhomogeneities can be reduced by shimming.  Study II aimed to investigate the use of shimming to improve the homogeneity of local  B0 magnetic field which will be beneficial for radiotherapy applications. A shimming simulation based on spherical harmonics modeling was developed. The spinal cord, an organ at risk is surrounded by bone and in close proximity to the lungs may have high susceptibility differences. In this region, mean pixel shifts caused by local B0 field inhomogeneities were reduced from 3.47±1.22 mm to 1.35±0.44 mm and 0.99±0.30 mm using first and second order shimming respectively. This was for a bandwidth of 122 Hz/pixel and an in-plane voxel size of 1×1 mm2.  Also examined in Study II as in Study I was the dosimetric effect of geometric distortions on 21 Head and Neck cancer treatment plans. The dose difference in D50 at the PTV between distorted CT and real CT plans was less than 1.0%.

    In conclusion, the effect of MR geometric distortions on dose plans was small. Generally, we found patient-induced susceptibility distortions were larger compared with residual system distortions at all delineated structures except the external contour. This information will be relevant when setting margins for treatment volumes and organs at risk.  

    The current practice of characterizing MR geometric distortions utilizing spatial accuracy phantoms alone may not be enough for an MR-only radiotherapy workflow. Therefore, measures to mitigate patient-induced susceptibility effects in clinical practice such as patient-specific correction algorithms are needed to complement existing distortion reduction methods such as high acquisition bandwidth and shimming.

  • 329.
    Adjeiwaah, Mary
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Bylund, Mikael
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Lundman, Josef A.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Söderström, Karin
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Zackrisson, Björn
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Jonsson, Joakim H.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Garpebring, Anders
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nyholm, Tufve
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Dosimetric Impact of MRI Distortions: A Study on Head and Neck Cancers2019In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 103, no 4, p. 994-1003Article in journal (Refereed)
    Abstract [en]

    Purpose: To evaluate the effect of magnetic resonance (MR) imaging (MRI) geometric distortions on head and neck radiation therapy treatment planning (RTP) for an MRI-only RTP. We also assessed the potential benefits of patient-specific shimming to reduce the magnitude of MR distortions for a 3-T scanner.

    Methods and Materials: Using an in-house Matlab algorithm, shimming within entire imaging volumes and user-defined regions of interest were simulated. We deformed 21 patient computed tomography (CT) images with MR distortion fields (gradient nonlinearity and patient-induced susceptibility effects) to create distorted CT (dCT) images using bandwidths of 122 and 488 Hz/mm at 3 T. Field parameters from volumetric modulated arc therapy plans initially optimized on dCT data sets were transferred to CT data to compute a new plan. Both plans were compared to determine the impact of distortions on dose distributions.

    Results: Shimming across entire patient volumes decreased the percentage of voxels with distortions of more than 2 mm from 15.4% to 2.0%. Using the user-defined region of interest (ROI) shimming strategy, (here the Planning target volume (PTV) was the chosen ROI volume) led to increased geometric for volumes outside the PTV, as such voxels within the spinal cord with geometric shifts above 2 mm increased from 11.5% to 32.3%. The worst phantom-measured residual system distortions after 3-dimensional gradient nonlinearity correction within a radial distance of 200 mm from the isocenter was 2.17 mm. For all patients, voxels with distortion shifts of more than 2 mm resulting from patient-induced susceptibility effects were 15.4% and 0.0% using bandwidths of 122 Hz/mm and 488 Hz/mm at 3 T. Dose differences between dCT and CT treatment plans in D-50 at the planning target volume were 0.4% +/- 0.6% and 0.3% +/- 0.5% at 122 and 488 Hz/mm, respectively.

    Conclusions: The overall effect of MRI geometric distortions on data used for RTP was minimal. Shimming over entire imaging volumes decreased distortions, but user-defined subvolume shimming introduced significant errors in nearby organs and should probably be avoided.

  • 330.
    Adjeiwaah, Mary
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Bylund, Mikael
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Lundman, Josef A.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Thellenberg Karlsson, Camilla
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Jonsson, Joakim H.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Nyholm, Tufve
    Umeå University, Faculty of Medicine, Department of Radiation Sciences. Medical Radiation Physics, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.
    Quantifying the effect of 3T MRI residual system and patient-induced susceptibility distortions on radiotherapy treatment planning for prostate cancer2018In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 100, no 2, p. 317-324Article in journal (Refereed)
    Abstract [en]

    Purpose: To investigate the effect of magnetic resonance system- and patient-induced susceptibility distortions from a 3T scanner on dose distributions for prostate cancers.

    Methods and Materials: Combined displacement fields from the residual system and patient-induced susceptibility distortions were used to distort 17 prostate patient CT images. VMAT dose plans were initially optimized on distorted CT images and the plan parameters transferred to the original patient CT images to calculate a new dose distribution.

    Results: Maximum residual mean distortions of 3.19 mm at a radial distance of 25 cm and maximum mean patient-induced susceptibility shifts of 5.8 mm were found using the lowest bandwidth of 122 Hz per pixel. There was a dose difference of <0.5% between distorted and undistorted treatment plans. The 90% confidence intervals of the mean difference between the dCT and CT treatment plans were all within an equivalence interval of (−0.5, 0.5) for all investigated plan quality measures.

    Conclusions: Patient-induced susceptibility distortions at high field strengths in closed bore magnetic resonance scanners are larger than residual system distortions after using vendor-supplied 3-dimensional correction for the delineated regions studied. However, errors in dose due to disturbed patient outline and shifts caused by patient-induced susceptibility effects are below 0.5%.

  • 331. Adlard, B.
    et al.
    Donaldson, S. G.
    Odland, J. O.
    Weihe, P.
    Berner, J.
    Carlsen, A.
    Bonefeld-Jorgensen, E. C.
    Dudarev, A. A.
    Gibson, J. C.
    Krümmel, E. M.
    Olafsdottir, K.
    Abass, K.
    Rautio, A.
    Bergdahl, Ingvar A.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Mulvad, G.
    Future directions for monitoring and human health research for the Arctic Monitoring and Assessment Programme2018In: Global Health Action, ISSN 1654-9716, E-ISSN 1654-9880, Vol. 11, no 1, article id 1480084Article in journal (Refereed)
    Abstract [en]

    For the last two and a half decades, a network of human health experts under the Arctic Monitoring and Assessment Program (AMAP) has produced several human health assessment reports. These reports have provided a base of scientific knowledge regarding environmental contaminants and their impact on human health in the Arctic. These reports provide scientific information and policy-relevant recommendations to Arctic governments. They also support international agreements such as the Stockholm Convention on Persistent Organic Pollutants (POPs) and the Minamata Convention on Mercury. Key topics discussed in this paper regarding future human health research in the circumpolar Arctic are continued contaminant biomonitoring, health effects research and risk communication. The objective of this paper is to describe knowledge gaps and future priorities for these fields.

  • 332.
    Adler, John
    Umeå University, Faculty of Social Sciences, Statistics.
    Statistical models for estimating career mobility2003Licentiate thesis, monograph (Other academic)
  • 333. Adler, P H
    et al.
    Malmqvist, Björn
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Predation on black flies (Diptera: Simuliidae) by the carnivorous plant Pinguicula vulgaris (Lentibulariaceae) in northern Sweden2004In: Entomologica Fennica, ISSN 0785-8760, Vol. 15, p. 124-128Article in journal (Refereed)
  • 334.
    Adler, Robert
    et al.
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Eriksson, Andreas
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Visuella Effekter Inom Genrespecifik Musikvideoproduktion2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today almost every artist has a music video. With today’s technology it has become a lot easier for smaller companies or amateur filmers to produce and distribute their work. But how important is an artist’s music video and where do people find their music these days? Other questions we wanted to answer were if there is a typical way a music video looks like based on its genre. And is it possible to break these stereotypical ways of producing music videos and thereby create a higher level of enjoyment from the viewer? Our main idea of achieving this was by the use of visual effects in a genre, which in our opinion usually don’t showcase these types of effects. The genre we decided to work with was singer/songwriter, which we think is one genre that doesn’t typically use visual effects. To back up our opinions we studied a lot of music videos from different genres to really see what was typical for each of them. Furthermore we made a survey to find answers for our questions about people’s views on the importance of a well-made music video and where they watch and find them. After we had found some of our answers we produced a music video, one with, and one without visual effects. We then showed these to a number of people and asked them questions about their opinions. Based on our results from studying different music videos and the surveys we came up with a conclusion. And we can say that using visual effects in a genre were they typically aren’t used is possible and it can enhance a viewers enjoyment of the music video. Although we also found out that it should be done with moderation and in good relations with the specific genre.

  • 335.
    Adler, Sara
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Cryptosporidium hominis in children-symptoms and risk factors. Data from a large water-borne outbreak in Sweden.2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 336. Adler, Sara
    et al.
    Widerström, Micael
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindh, Johan
    Lilja, Mikael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Symptoms and risk factors of Cryptosporidium hominis infection in children: data from a large waterborne outbreak in Sweden2017In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 116, no 10, p. 2613-2618Article in journal (Refereed)
    Abstract [en]

    Cryptosporidium is a major cause of diarrheal disease worldwide. In developing countries, this infection is endemic and in children, associated with growth faltering and cognitive function deficits, with the most severe impact on those aged <2 years. Little has been reported about symptoms and risk factors for children in industrialized countries, although the disease incidence is increasing in such regions. In November 2010, a large waterborne outbreak of C. hominis occurred in the city of Östersund in Sweden. Approximately 27,000 of the 60,000 inhabitants were symptomatic. We aimed to describe duration of symptoms and the risk factors for infection with C. hominis in children aged <15 years in a Western setting. Within 2 months after a boil water advisory, a questionnaire was sent to randomly selected inhabitants of all ages, including 753 children aged <15 years. Those with ≥3 loose stools/day were defined as cases of diarrhoea. The response rate was 70.3%, and 211 children (39.9%) fulfilled the case definition. Mean duration of diarrhoea was 7.5 days (median 6, range 1-80 days). Recurrence, defined as a new episode of diarrhoea after ≥2 days of normal stools, occurred in 52.5% of the cases. Significant risk factors for infection, besides living within the distribution area of the contaminated water plant, included a high level of water consumption, male sex, and a previous history of loose stools. The outbreak was characterized by high attack and recurrence rates, emphasizing the necessity of water surveillance to prevent future outbreaks.

  • 337.
    Adlerborn, Björn
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Parallel Algorithms and Library Software for the Generalized Eigenvalue Problem on Distributed Memory Computer Systems2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    We present and discuss algorithms and library software for solving the generalized non-symmetric eigenvalue problem (GNEP) on high performance computing (HPC) platforms with distributed memory. Such problems occur frequently in computational science and engineering, and our contributions make it possible to solve GNEPs fast and accurate in parallel using state-of-the-art HPC systems. A generalized eigenvalue problem corresponds to finding scalars y and vectors x such that Ax = yBx, where A and B are real square matrices. A nonzero x that satisfies the GNEP equation is called an eigenvector of the ordered pair (A,B), and the scalar y is the associated eigenvalue. Our contributions include parallel algorithms for transforming a matrix pair (A,B) to a generalized Schur form (S,T), where S is quasi upper triangular and T is upper triangular. The eigenvalues are revealed from the diagonals of S and T. Moreover, for a specified set of eigenvalues an associated pair of deflating subspaces can be computed, which typically is requested in various applications. In the first stage the matrix pair (A,B) is reduced to a Hessenberg-triangular form (H,T), where H is upper triangular with one nonzero subdiagonal and T is upper triangular, in a finite number of steps. The second stage reduces the matrix pair further to generalized Schur form (S,T) using an iterative QZ-based method. Outgoing from a one-stage method for the reduction from (A,B) to (H,T), a novel parallel algorithm is developed. In brief, a delayed update technique is applied to several partial steps, involving low level operations, before associated accumulated transformations are applied in a blocked fashion which together with a wave-front task scheduler makes the algorithm scale when running in a parallel setting. The potential presence of infinite eigenvalues makes a generalized eigenvalue problem ill-conditioned. Therefore the parallel algorithm for the second stage, reduction to (S,T) form, continuously scan for and robustly deflate infinite eigenvalues. This will reduce the impact so that they do not interfere with other real eigenvalues or are misinterpreted as real eigenvalues. In addition, our parallel iterative QZ-based algorithm makes use of multiple implicit shifts and an aggressive early deflation (AED) technique, which radically speeds up the convergence. The multi-shift strategy is based on independent chains of so called coupled bulges and computational windows which is an important source of making the algorithm scalable. The parallel algorithms have been implemented in state-of-the-art library software. The performance is demonstrated and evaluated using up to 1600 CPU cores for problems with matrices as large as 100000 x 100000. Our library software is described in a User Guide. The software is, optionally, tunable via a set of parameters for various thresholds and buffer sizes etc. These parameters are discussed, and recommended values are specified which should result in reasonable performance on HPC systems similar to the ones we have been running on.

  • 338.
    Adlerborn, Björn
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Karlsson, Lars
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kågström, Bo
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Distributed one-stage Hessenberg-triangular reduction with wavefront scheduling2018In: SIAM Journal on Scientific Computing, ISSN 1064-8275, E-ISSN 1095-7197, Vol. 40, no 2, p. C157-C180Article in journal (Refereed)
    Abstract [en]

    A novel parallel formulation of Hessenberg-triangular reduction of a regular matrix pair on distributed memory computers is presented. The formulation is based on a sequential cacheblocked algorithm by K degrees agstrom et al. [BIT, 48 (2008), pp. 563 584]. A static scheduling algorithm is proposed that addresses the problem of underutilized processes caused by two-sided updates of matrix pairs based on sequences of rotations. Experiments using up to 961 processes demonstrate that the new formulation is an improvement of the state of the art and also identify factors that limit its scalability.

  • 339.
    Adlerborn, Björn
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kågström, Bo
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Karlsson, Lars
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Distributed one-stage Hessenberg-triangular reduction with wavefront scheduling2016Report (Other academic)
    Abstract [en]

    A novel parallel formulation of Hessenberg-triangular reduction of a regular matrix pair on distributed memory computers is presented. The formulation is based on a sequential cache-blocked algorithm by Kågstrom, Kressner, E.S. Quintana-Ortí, and G. Quintana-Ortí (2008). A static scheduling algorithm is proposed that addresses the problem of underutilized processes caused by two-sided updates of matrix pairs based on sequences of rotations. Experiments using up to 961 processes demonstrate that the new algorithm is an improvement of the state of the art but also identifies factors that currently limit its scalability.

  • 340.
    Adlerborn, Björn
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kågström, Bo
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kressner, Daniel
    A parallel QZ algorithm for distributed memory HPC systems2014In: SIAM Journal on Scientific Computing, ISSN 1064-8275, E-ISSN 1095-7197, Vol. 36, no 5, p. C480-C503Article in journal (Refereed)
    Abstract [en]

    Appearing frequently in applications, generalized eigenvalue problems represent one of the core problems in numerical linear algebra. The QZ algorithm of Moler and Stewart is the most widely used algorithm for addressing such problems. Despite its importance, little attention has been paid to the parallelization of the QZ algorithm. The purpose of this work is to fill this gap. We propose a parallelization of the QZ algorithm that incorporates all modern ingredients of dense eigensolvers, such as multishift and aggressive early deflation techniques. To deal with (possibly many) infinite eigenvalues, a new parallel deflation strategy is developed. Numerical experiments for several random and application examples demonstrate the effectiveness of our algorithm on two different distributed memory HPC systems.

  • 341.
    Adlerborn, Björn
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kågström, Bo
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kressner, Daniel
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Parallel Variants of the Multishift QZ Algorithm with Advanced Deflation Techniques2007In: Applied Parallel Computing - State of the Art in Scientific Computing: 8th International Workshop, PARA 2006, Springer , 2007, p. 117-126Conference paper (Refereed)
    Abstract [en]

    The QZ algorithm reduces a regular matrix pair to generalized Schur form, which can be used to address the generalized eigenvalue problem. This paper summarizes recent work on improving the performance of the QZ algorithm on serial machines and work in progress on a novel parallel implementation. In both cases, the QZ iterations are based on chasing chains of tiny bulges. This allows to formulate the majority of the computation in terms of matrix-matrix multiplications, resulting in natural parallelism and better performance on modern computing systems with memory hierarchies. In addition, advanced deflation strategies are used, specifically the so called aggressive early deflation, leading to a considerable convergence acceleration and consequently to a reduction of floating point operations and computing time.

  • 342.
    Adlerborn, Björn
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kågström, Bo
    Umeå University, Faculty of Science and Technology, Department of Computing Science. Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Kressner, Daniel
    SB–MATHICSE–ANCHP, EPF Lausanne.
    PDHGEQZ user guide2015Report (Other academic)
    Abstract [en]

    Given a general matrix pair (A,B) with real entries, we provide software routines for computing a generalized Schur decomposition (S, T). The real and complex conjugate pairs of eigenvalues appear as 1×1 and 2×2 blocks, respectively, along the diagonals of (S, T) and can be reordered in any order. Typically, this functionality is used to compute orthogonal bases for a pair of deflating subspaces corresponding to a selected set of eigenvalues. The routines are written in Fortran 90 and targets distributed memory machines.

  • 343.
    Adman, Per
    et al.
    Uppsala universitet.
    Eckerberg, Katarina
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Öhlander, Magnus
    91 forskare: I dag bör vi alla klimatprotestera: ”Vi vuxna har en skyldighet att engagera oss”2019In: Aftonbladet, ISSN 1103-9000, , p. 1Article in journal (Other (popular science, discussion, etc.))
    Abstract [sv]

    Runt om världen skolstrejkas det mot att alltför lite görs för att stoppa klimatförändringarna. Hundratusentals ungdomar i över hundra länder har engagerat sig i vad som blivit till en global rörelse.

    I dag planeras för de mest omfattande protesterna hittills.

    Budskapet är det samma som klimatforskarnas, alltså att rådande klimatpolitik och utsläppsnivåer måste läggas om radikalt snarast, annars hotar en global katastrof. Tusentals belgiska och engelska forskare har i öppna brev bekräftat att budskapet stämmer. Därför har alla vi vuxna medborgare en skyldighet att engagera oss. I slutändan krävs politiskt ledarskap. De folkvalda måste axla sitt ansvar, erkänna situationens allvar, diskutera och besluta om nödvändiga policyer och se till att dessa genomförs; det är vår skyldighet som demokratiska medborgare att pressa dem till detta, så länge de inte gör det på eget initiativ.

  • 344. Adnan, Muhammad
    et al.
    Iqbal, Javed
    Bibi, Shamsa
    Hussain, Riaz
    Akhtar, Muhammad Nadeem
    Rashid, Muhammad Abid
    Eliasson, Bertil
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ayub, Khurshid
    Fine Tuning the Optoelectronic Properties of Triphenylamine Based Donor Molecules for Organic Solar Cells2017In: Zeitschrift fur physikalische Chemie (Munchen. 1991), ISSN 0942-9352, Vol. 231, no 6, p. 1127-1139Article in journal (Refereed)
    Abstract [en]

    Geometrical parameters, electronic structures and photophysical properties of three new triphenylamine (TPA) and diphenylamine (DPA) based electron donor materials M1-M3 (for organic solar cells) have been investigated through density functional theory (DFT) methods at the B3LYP/6-31G(d) level of the theory. TPA and DPA are used as donor moieties due to their electron donating ability while benzothiazole, cyanide and cyanomethylacetate (CMA) moieties have been taken as acceptor moieties. The time dependent-DFT (TD-DFT) method has been employed [TD-B3LYP/6-31G (d)] for the computation of excited state properties in the gas phase and in solvent (chloroform). The polarization continuum model is applied for calculations in the solvent phase. The designed molecules exhibited broad absorption in the visible and near infra-red region of spectrum with respect to a reference molecule "R" of a similar class of compounds. Based on reorganization energies calculations, these materials could act as excellent hole transport materials.

  • 345.
    Adner, Kristin
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Axelsson, Therese
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Acceptance and Commitment Therapy i arbetet med barn och ungdomar: Behandlares erfarenheter och upplevelser av att anpassa och utöva metoden2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study has examined therapists’ adjustments of ACT with children and adolescents and experiences of practicing the method with said group. Interviews were conducted with seven psychologists and data was analyzed using thematic analysis. Results showed general child-therapeutic adjustments, combining ACT with tCBT and modifications of the ACT principles. Challenges were working with a context with a different agenda, to be flexible and daring to be active and weird. Another challenge was working with a method that isn’t implemented in the workplace and has an uncertain future. Possibilities included using ACT for oneself, working towards positive goals and having fun. Additionally, a view of ACT as a philosophy of life was presented. Dilemmas concerning the use of a method lacking evidence were also presented. Future research can examine the impact of the different ACT principles on psychological flexibility in youths and how challenges in treatment can be overcome.

  • 346. Adolf, Carole
    et al.
    Wunderle, Stefan
    Colombaroli, Daniele
    Weber, Helga
    Gobet, Erika
    Heiri, Oliver
    van Leeuwen, Jacqueline F. N.
    Bigler, Christian
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Connor, Simon E.
    Galka, Mariusz
    La Mantia, Tommaso
    Makhortykh, Sergey
    Svitavska-Svobodova, Helena
    Vanniere, Boris
    Tinner, Willy
    The sedimentary and remote-sensing reflection of biomass burning in Europe2018In: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 27, no 2, p. 199-212Article in journal (Refereed)
    Abstract [en]

    Aim: We provide the first European-scale geospatial training set relating the charcoal signal in surface lake sediments to fire parameters (number, intensity and area) recorded by satellite moderate resolution imaging spectroradiometer (MODIS) sensors. Our calibration is intended for quantitative reconstructions of key fire-regime parameters by using sediment sequences of microscopic (MIC from pollen slides, particles 10-500 mu m) and macroscopic charcoal (MAC from sieves, particles > 100 mu m). Location: North-south and east-west transects across Europe, covering the mediterranean, temperate, alpine, boreal and steppe biomes. Time period: Lake sediments and MODIS active fire and burned area products were collected for the years 2012-2015. Methods: Cylinder sediment traps were installed in lakes to annually collect charcoal particles in sediments. We quantitatively assessed the relationships between MIC and MAC influx (particles/cm(2)/year) and the MODIS-derived products to identify source areas of charcoal and the extent to which lake-sediment charcoal is linked to fire parameters across the continent. Results: Source area of sedimentary charcoal was estimated to a 40-km radius around sites for both MIC and MAC particles. Fires occurred in grasslands and in forests, with grass morphotypes of MAC accurately reflecting the burned fuel-type. Despite the lack of local fires around the sites, MAC influx levels reached those reported for local fires. Both MIC and MAC showed strong and highly significant relationships with the MODIS-derived fire parameters, as well as with climatic variation along a latitudinal temperature gradient. Main conclusions: MIC and MAC are suited to quantitatively reconstructing fire number and fire intensity on a regional scale. However, burned area may only be estimated using MAC. Local fires may be identified by using several lines of evidence, e.g. analysis of large particles (> 600 mu m), magnetic susceptibility and sedimentological data. Our results offer new insights and applications to quantitatively reconstruct fires and to interpret available sedimentary charcoal records.

  • 347. Adolf, Katja
    et al.
    Wagner, Ludwig
    Bergh, Anders
    Umeå University, Faculty of Medicine, Medical Biosciences, Pathology.
    Stattin, Pär
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Urology and Andrology.
    Ottosen, Peter
    Borre, Michael
    Birkenkamp-Demtröder, Karin
    Orntoft, Torben Falck
    Tørring, Niels
    Secretagogin is a new neuroendocrine marker in the human prostate.2007In: Prostate, ISSN 0270-4137, Vol. 67, no 5, p. 472-84Article in journal (Refereed)
  • 348.
    Adolfsson, Amanda
    Umeå University, Faculty of Social Sciences, Department of Law.
    Assisterad befruktning. Den ofrivilligt barnlösas rätt att bli förälder eller barnets bästa?2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 349.
    Adolfsson, Anna
    et al.
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Jonsén, Jennie
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Local participation and the urban poor2003Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 350.
    Adolfsson, Camilla
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    En polisutbildning med hänsyn till det intersektionella?2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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