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  • 801.
    Aigner, Harald
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Characterization of FtsH proteases in the annual plant Arabidopsis thaliana2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background FtsH is an ATP-dependent membrane-bound metalloprotease. A. thaliana contains 12 FtsH proteases localized in membranes of chloroplasts and mitochondria where they form homo- or hetero-hexameric complexes. FtsH11 – the main subject of this thesis – is located in the chloroplast envelope.

     

    Methods

    • Field studies with A. thaliana to determine Darwinian fitness. A growth under outdoor conditions often allows discovering of phenotypes that are unascertainable in the controlled environment of growth chambers.
    • Proteomic methods to discover fragments of substrate proteins (limited proteolysis) and changes in the proteome of FtsH protease deficient mutants.

     

    Results ftsh11 has increased amount of: RuBisCO activase, several Calvin cycle enzymes, two enzymes involved in starch synthesis and some chaperons. Some of those enzymes have been identified as possible substrates of FtsH11. Under long photoperiods ftsh11 develops a chlorotic phenotype accompanied by decreasing NADP+/NADPH ratio and increase of ROS damaged proteins. 

  • 802.
    Aigner, Harald
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Comparison of hypothetical 3D-structures of Arabidopsis thaliana FtsH Proteases with the aim to predict FtsH complex formationManuscript (preprint) (Other academic)
    Abstract [en]

    In Arabidopsis thaliana 12 metallo proteases of the FtsH family are located in the organellar membranes of chloroplasts and mitochondria. While it is known for the Arabidopsis FtsH proteases FtsH1, 2, 5 and 8 to form a hetero–oligomeric, hexameric complex in the chloroplast thylakoid membrane and for FtsH3 and 10 in the inner membrane of mitochondria, no data are available for the remaining (low abundant) FtsH proteases . We compared the sequence identity of amino acids predicted to be relevant in complex formation of FtsH proteases in order to predict additional hetero-oligomeric FtsH complexes. Focus was set on FtsH11 and FtsH4, two subunits that might form a complex in mitochondria. 

  • 803.
    Aigner, Harald
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Searching for substrates of the metallo protease FtsH11 of Arabidopsis thaliana using N-terminal proteomics2012Manuscript (preprint) (Other academic)
    Abstract [en]

    FtsH11 is a membrane-bound metalloprotease localized in mitochondria and in the chloroplast envelope of Arabidopsis thaliana. An ftsh11 knock-out mutant has been shown to develop a chlorotic phenotype in prolonged photoperiods. The proteome of the ftsh11 chloroplast revealed increased abundance of several Calvin cycle enzymes, chaperones and some other proteins, however, none of those proteins could be verified to be an FtsH11 substrate (Harald Aigner, Raik Wagner, Lars L.E. Sjögren, Holger Eubel, A. Harvey Millar, Adrian K. Clarke, Christiane Funk, 2012, manuscript submitted). Here, we have used positional proteomics to identify peptides that report FtsH11 processing events. In this work we were able to identify seven chloroplast-localized proteins that are processed in wild type, but not in ftsh11.  

  • 804.
    Aigner, Harald
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Wagner, Raik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Sjögren, Lars
    Eubel, Holger
    Millar, Harvey
    Clarke, Adrian
    Funk, Christiane
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    FtsH11 protease is required for Arabidopsis thaliana to adapt to gtowth in continuous lightManuscript (preprint) (Other academic)
    Abstract [en]

    Continuous light can increase greenhouse food production; however, some of the most important greenhouse horticulture crops are not able to adapt to long photoperiods. Here, we provide evidence that knock-out of the FtsH11 protease causes molecular differences that prevent Arabidopsis thaliana to adapt to prolonged photoperiods. Previously this protease had been shown to be critical for thermotolerance (Chen et al. 2006). We demonstrate that knock-out mutants deficient of FtsH11 develop chlorosis when shifted to continuous light. When grown under normal growth conditions and short days, ftsh11 displayed changes in protein amount of chloroplast proteins involved in the photosynthetic light reaction and the Calvin cycle as well as of the FtsH12 protease. The proteomic changes are accompanied by reduced non-photochemical quenching and faster state transition. A shift to continuous light further enhanced these effects and induced morphological changes of the chloroplast and chlorosis. No changes in the mitochondrial proteome were observed between wild type and ftsh11.

  • 805. Aikio, Anita T.
    et al.
    Pitkänen, Timo
    Fontaine, Dominic
    Dandouras, Iannis
    Amm, Olaf
    Kozlovsky, Alexander
    Vaivads, Andris
    Fazakerley, Andrew
    EISCAT and Cluster observations in the vicinity of the dynamical polar cap boundary2008In: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 26, p. 87-105Article in journal (Refereed)
  • 806.
    Aikio, Anita T.
    et al.
    Department of Physical Sciences, University of Oulu, Finland.
    Pitkänen, Timo
    Department of Physical Sciences, University of Oulu, Finland.
    Fontaine, Dominic
    CETP/UVSQ, Velizy, France.
    Dandouras, Iannis
    CESR/CNRS, Toulouse, France.
    Amm, Olaf
    Finnish meteorological Institute, Helsinki, Finland.
    Kozlovsky, Alexander
    Department of Physical Sciences, University of Oulu, Finland; Sodankylä Geophysical Observatory, Sodankylä, Finland.
    Vaivads, Andris
    Swedish Institute of Space Physics, Ångströmlaboratoriet, Uppsala, Sweden.
    Fazakerley, Andrew
    Mullard Space Science Laboratory, University College, London, UK.
    EISCAT and Cluster observations in the vicinity of the dynamical polar cap boundary2008In: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 26, p. 87-105Article in journal (Refereed)
    Abstract [en]

    The dynamics of the polar cap boundary and auroral oval in the nightside ionosphere are studied during late expansion and recovery of a substorm from the region between Tromsø (66.6 degree cgmLat) and Longyearbyen (75.2 degree cgmLat) on 27 February 2004 by using the coordinated EISCAT incoherent scatter radar, MIRACLE magnetometer and Cluster satellite measurements. During the late substorm expansion/early recovery phase, the polar cap boundary (PCB) made zig-zag-type motion with amplitude of 2.5 degree cgmLat and period of about 30 min near magnetic midnight. We suggest that the poleward motions of the PCB were produced by bursts of enhanced reconnection at the near-Earth neutral line (NENL). The subsequent equatorward motions of the PCB would then represent the recovery of the merging line towards the equilibrium state (Cowley and Lockwood, 1992). The observed bursts of enhanced westward electrojet just equatorward of the polar cap boundary during poleward expansions were produced plausibly by particles accelerated in the vicinity of the neutral line and thus lend evidence to the Cowley-Lockwood paradigm.

    During the substorm recovery phase, the footpoints of the Cluster satellites at a geocentric distance of 4.4RE mapped in the vicinity of EISCAT measurements. Cluster data indicate that outflow of H+ and O+ ions took place within the plasma sheet boundary layer (PSBL) as noted in some earlier studies as well. We show that in this case the PSBL corresponded to a region of enhanced electron temperature in the ionospheric F region. It is suggested that the ion outflow originates from the F region as a result of increased ambipolar diffusion. At higher altitudes, the ions could be further energized by waves, which at Cluster altitudes were observed as BBELF (broad band extra low frequency) fluctuations.

    The four-satellite configuration of Cluster revealed a sudden poleward expansion of the PSBL by 2 degree during ˜ 5 min. The beginning of the poleward motion of the PCB was associated with an intensification of the downward FAC at the boundary. We suggest that the downward FAC sheet at the PCB is the high-altitude counterpart of the Earthward flowing FAC produced in the vicinity of the magnetotail neutral line by the Hall effect (Sonnerup, 1979) during a short-lived reconnection pulse.

  • 807. Aikio, Anita T.
    et al.
    Pitkänen, Timo
    Honkonen, Ilja
    Palmroth, Minna
    Amm, Olaf
    IMF effect on the polar cap contraction and expansion during a period of substorms2013In: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 31, p. 1021-1034Article in journal (Refereed)
  • 808.
    Aikio, Anita T.
    et al.
    Oulu, Finland.
    Pitkänen, Timo
    Oulu, Finland.
    Honkonen, Ilja
    Helsinki, Finland.
    Palmroth, Minna
    Helsinki, Finland.
    Amm, Olaf
    Helsinki, Finland.
    IMF effect on the polar cap contraction and expansion during a period of substorms2013In: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 31, p. 1021-1034Article in journal (Refereed)
    Abstract [en]

    The polar cap boundary (PCB) location and motion in the nightside ionosphere has been studied by using measurements from the EISCAT radars and the MIRACLE magnetometers during a period of four substorms on 18 February 2004. The OMNI database has been used for observations of the solar wind and the Geotail satellite for magnetospheric measurements. In addition, the event was modelled by the GUMICS-4 MHD simulation. The simulation of the PCB location was in a rather good agreement with the experimental estimates at the EISCAT longitude. During the first three substorm expansion phases, neither the local observations nor the global simulation showed any poleward motions of the PCB, even though the electrojets intensified. Rapid poleward motions of the PCB took place only in the early recovery phases of the substorms. Hence, in these cases the nightside reconnection rate was locally higher in the recovery phase than in the expansion phase.

    In addition, we suggest that the IMF Bz component correlated with the nightside tail inclination angle and the PCB location with about a 17-min delay from the bow shock. By taking the delay into account, the IMF northward turnings were associated with dipolarizations of the magnetotail and poleward motions of the PCB in the recovery phase. The mechanism behind this effect should be studied further.

  • 809. Aikio, Anita T.
    et al.
    Pitkänen, Timo
    Kozlovsky, Alexander
    Amm, Olaf
    Method to locate the polar cap boundary in the nightside ionosphere and application to a substorm event2006In: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 24, p. 1905-1917Article in journal (Refereed)
  • 810.
    Ailert Andersson, Natalie
    et al.
    Umeå University, Faculty of Social Sciences, Department of Food and Nutrition.
    Persson, Linn
    Umeå University, Faculty of Social Sciences, Department of Food and Nutrition.
    Föreställningar och attityder till mellanmål hos studenter vid Umeå universitet och Sveriges lantbruksuniversitet2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background In-between meals can include anything consumed between breakfast, lunch and dinner. There are no explicit recommendations about in-between meals in Sweden. Dietary habits are affected by social norms and peers. Usually dietary habits change during college or university. The eating habits created during this time is often kept for the future.

    Objective Examine students’ ideas about and attitudes towards in-between meals.

    Method Eight semi-structured individual interviews were held with students from Swedish University of Agricultural Sciences and Umeå University. The participants were recruited by the authors at both Universities. The interviews were recorded and transcribed word by word. The data collection was analyzed using a qualitative content analysis.

    Results The participants had different views about in-between meals. Some believed in-between meals was a good thing while others thought it was pointless. Lack of time and bad planning were the biggest reasons not to have in-between meals. The participants described that their friends and acquaintances affected their in-between meals. The participants believed that a person’s body shape and what they ate affected how they saw that person. Some of the female participants brought up social pressure about weight and how it restrained their food choices.

    Conclusion Individuals greatly differed in their opinions towards in-between meals and when it should be consumed. Assortment, social norms and peers was affecting student's thoughts and action towards in-between meals. More research is required to see if there is a need for general advice about in-between meals and how they should be mediated. More research is also required about social norms and in-between meals, but also about their health benefits.

  • 811.
    Ailert, Moa
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies.
    Avsikt, insikt och moraliskt ansvar: En genomgång av diskussionen gällande doktrinen om trippel effekt mellan Frances M. Kamm och John Harris.2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 812.
    Aili, Margareta
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Role of YopE and LcrH in effector translocation, HeLa cell cytotoxicity and virulence2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In order to establish an extra-cellular infection the gram-negative bacteria Yersinia pseudotuberculosis uses a type III secretion system (T3SS) to translocate a set of anti-host effectors into eukaryotic cells. The toxins disrupt signalling pathways important for phagocytosis, cytokine production and cell survival. Secretion and translocation via this T3SS is strictly regulated on several levels. In this context, the function of YopE and LcrH during Yersinia infections has been analysed.

    YopE is an essential translocated effector that disrupts the actin cytoskeleton of infected eukaryotic cells, by inactivating small GTPases through its GTPase activating protein (GAP) activity. However, cytotoxicity can be uncoupled from in vitro GAP activity towards the RhoA, Rac1 and Cdc42 GTPases. Furthermore, in vivo studies of the YopE GAP activity revealed that only RhoA and Rac1 are targeted, but this is not a pre-requisite for Yersinia virulence. Hence, YopE must target one or more additional GTPases to cause disease in mice.

    YopE was the only Yersinia effector that blocks LDH release from infected cells. Moreover, translocated YopE could regulate the level of subsequent effector translocation by a mechanism that involved the YopE GAP function and another T3S component, YopK. Loss of translocation control elevated total T3S gene expression in the presence of eukaryotic cells. This indicated the existence of a regulatory loop for feedback control of T3S gene expression in the bacteria that originates from the interior of the eukaryotic cell after effector translocation is completed. This might represent the true virulence function of YopE.

    Exoenzyme S (ExoS) of Pseudomonas aeruginosa has a YopE-like GAP domain with similar activity towards RhoA, Rac1 and Cdc42. However, ExoS is unable to complement hyper-translocation resulting from loss of YopE. This indicates a unique function for YopE in translocation control in Yersinia that might be dependent on correct intracellular localisation. It follows that the Membrane Localisation Domain in YopE was important for translocation control, but dispensable for cytotoxicity and blockage of LDH release.

    YopD and its cognate chaperone LcrH are negative regulatory elements of the T3S regulon and together with YopB, are involved in the effector translocation process. Randomly generated point mutants in LcrH specifically effected stability and secretion of both the YopB and YopD substrates in vitro and prevented their apparent insertion as translocon pores in the membranes of infected cells. Yet, these mutants still produced stable substrates in the presence of eukaryotic cells and most could mediate at least partial effector translocation. Thus, only minimal amounts of the YopB and YopD translocator proteins are needed for translocation and the LcrH chaperone may regulate this process from inside the bacteria.

  • 813. Aili, Margareta
    et al.
    Hallberg, Bengt
    Wolf-Watz, Hans
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Rosqvist, Roland
    GAP activity of Yersinia YopE2002In: Methods in Enzymology, ISSN 0076-6879, E-ISSN 1557-7988, Vol. 358, p. 359-70Article in journal (Refereed)
  • 814.
    Aili, Margareta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Isaksson, Elin L
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Carlsson, Sara E
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Wolf-Watz, Hans
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Rosqvist, Roland
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Francis, Matthew S
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Regulation of Yersinia Yop-effector delivery by translocated YopE2008In: International Journal of Medical Microbiology, ISSN 1438-4221, E-ISSN 1618-0607, Vol. 298, no 3-4, p. 183-192Article in journal (Refereed)
    Abstract [en]

    The bacterial pathogen Yersinia pseudotuberculosis uses a type III secretion (T3S) system to translocate Yop effectors into eukaryotic cells. Effectors are thought to gain access to the cytosol via pores formed in the host cell plasma membrane. Translocated YopE can modulate this pore formation through its GTPase-activating protein (GAP) activity. In this study, we analysed the role of translocated YopE and all the other known Yop effectors in the regulation of effector translocation. Elevated levels of Yop effector translocation into HeLa cells occurred by YopE-defective strains, but not those defective for other Yop effectors. Only Yersinia devoid of YopK exhibits a similar hyper-translocation phenotype. Since both yopK and yopE mutants also failed to down-regulate Yop synthesis in the presence of eukaryotic cells, these data imply that translocated YopE specifically regulates subsequent effector translocation by Yersinia through at least one mechanism that involves YopK. We suggest that the GAP activity of YopE might be working as an intra-cellular probe measuring the amount of protein translocated by Yersinia during infection. This may be a general feature of T3S-associated GAP proteins, since two homologues from Pseudomonas aeruginosa, exoenzyme S (ExoS) and exoenzyme T (ExoT), can complement the hyper-translocation phenotypes of the yopE GAP mutant.

  • 815.
    Aili, Margareta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Isaksson, Elin L
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Hallberg, Bengt
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Wolf-Watz, Hans
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Rosqvist, Roland
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Functional analysis of the YopE GTPase-activating protein (GAP) activity of Yersinia pseudotuberculosis2006In: Cellular Microbiology, ISSN 1462-5814, E-ISSN 1462-5822, Vol. 8, no 6, p. 1020-1033Article in journal (Refereed)
    Abstract [en]

    YopE of Yersinia pseudotuberculosis inactivates three members of the small RhoGTPase family (RhoA, Rac1 and Cdc42) in vitro and mutation of a critical arginine abolishes both in vitro GTPase-activating protein (GAP) activity and cytotoxicity towards HeLa cells, and renders the pathogen avirulent in a mouse model. To understand the functional role of YopE, in vivo studies of the GAP activity in infected eukaryotic cells were conducted. Wild-type YopE inactivated Rac1 as early as 5 min after infection whereas RhoA was down regulated about 30 min after infection. No effect of YopE was found on the activation state of Cdc42 in Yersinia-infected cells. Single-amino-acid substitution mutants of YopE revealed two different phenotypes: (i) mutants with significantly lowered in vivo GAP activity towards RhoA and Rac1 displaying full virulence in mice, and (ii) avirulent mutants with wild-type in vivo GAP activity towards RhoA and Rac1. Our results show that Cdc42 is not an in vivo target for YopE and that YopE interacts preferentially with Rac1, and to a lesser extent with RhoA, during in vivo conditions. Surprisingly, we present results suggesting that these interactions are not a prerequisite to establish infection in mice. Finally, we show that avirulent yopE mutants translocate YopE in about sixfold higher amount compared with wild type. This raises the question whether YopE's primary function is to sense the level of translocation rather than being directly involved in downregulation of the host defence.

  • 816.
    Aili, Margareta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Telepnev, Max
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Hallberg, Bengt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Wolf-Watz, Hans
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Rosqvist, Roland
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    In vitro GAP activity towards RhoA, Rac1 and Cdc42 is not a prerequisite for YopE induced HeLa cell cytotoxicity2003In: Microbial Pathogenesis, ISSN 0882-4010, E-ISSN 1096-1208, Vol. 34, no 6, p. 297-308Article in journal (Refereed)
    Abstract [en]

    The YopE cytotoxin of Yersinia is an essential virulence determinant that is translocated into the eukaryotic target cell via a plasmid-encoded type III secretion system. YopE possess a GTPase activating protein activity that in vitro has been shown to down regulate RhoA, Rac1, and Cdc42. Translocated YopE induces de-polymerisation of the actin microfilament structure in the eukaryotic cell which results in a rounding up of infected cells described as a cytotoxic effect. Here, we have investigated the importance of different regions of YopE for induction of cytotoxicity and in vitro GAP activity. Sequential removal of the N- and C-terminus of YopE identified the region between amino acids 90 and 215 to be necessary for induction of cytotoxicity. Internal deletions containing the essential arginine at position 144 resulted in a total loss of cytotoxic response. In-frame deletions flanking the arginine finger defined a region important for the cytotoxic effect to amino acids 166–183. Four triple-alanine substitution mutants in this region, YopE166-8A, 169-71A, 175-7A and 178-80A were still able to induce cytotoxicity on HeLa cells although they did not show any in vitro GAP activity towards RhoA, Rac1 or Cdc42. A substitution mutant in position 206-8A showed the same phenotype, ability to induce cytotoxic response but no in vitro GAP activity. We speculate that YopE may have additional unidentified targets within the eukaryotic cell.

  • 817.
    Aili Törmä, Maria
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies.
    Fornlämningen Luleå Gammelstad: De äldsta spåren från de arkeologiska undersökningarna inom Nederluleå socken Raä 330:1.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 818.
    Aimaiti, Nuerrennisahan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    A Comparison of Rotation Parameterisations for Bundle Adjustment2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Bundle Adjustment is an iterative process where 3D information is estimated from 2D image measurements. Typically, the position of object points are estimated simultaneously with the position and orientation of the cameras. While the object points and camera positions have a straightforward "natural" parameterisation, several possibilities exist for the rotation. In this thesis, seven parameterisation of the rotation were investigated; Euler angles (two variants), the Rodriguez representation, the axis-and-angle representation, unit quaternions, and two variants of the direction cosine matrix (DCM). The Euler and Rodriguez parameterisation are common in photogrammetry and each has three parameters. The other parameterisations have more parameters and one or more constraint between them.

    The parameterisations were analyzed with respect to singularities, i.e. well-defined rotations that do not have any bounded and/or unique set of parameters. Four bundle adjustment experiments were setup, each corresponding to a singularity for one or more parameterisations. A fitth, singularity-free, experiment was also added. The experiments were perturbation studies that investigated the convergence properties of each parameterisation. The unconstrained parameterisations were solved by a damped and undamped Gauss-Newton algorithm, whereas the parameterisations with constraints were solved using damped and undamped algorithms based on the Gauss-Helmert estimation model.

    As expected, the parameterisations corresponding to the constructed singularity had higher failure rates and required more iterations and execution time than the others when it did converge. Excluding their singular cases, the Euler xyz and Rodriguez representations were the fastest with about 37% of the dcm. Of the singularity-free parameterisation, the unit quaternion was the fastest with 79% of the dcm.

    Surprisingly, the undamped bundle algorithms converged more often and faster than the damped bundle algorithms, even close to singularities. However, the undamped convergence was to a higher degree associated with numerical warnings and convergence toward angular values outside the nominal 2 range.

    The results suggest that if singularities are not expected, the Euler xyz and Rodriguez representations are the best of the tested parameterisations. Otherwise, the unit quaternion is the best. As an alternative to the latter case, the switching algorithm by Singla may be used, at the expense of a more complex algorithm.

  • 819.
    Aimaiti, Nuerrennisahan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Yan, Xu
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Gestire-based Interaction and Implication for the Future2011Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Currently there exists an advanced and natural form of interaction, named gesture-based interaction. It has been applied in some fields successfully, especially in the form of game applications. Although people are filled with wonder at the new interaction, it has not replaced the traditional interaction, like keyboard and mouse. From the user experience point of view, gesture-based interaction has advantages which traditional interactive form cannot offer, but also shortcomings which people seem dissatisfied with. This thesis focuses on expressing user experience of gesture-based interaction by conducting interview method. Finally, this paper presents a new design and tries to find implications for its practical usage in the future.

  • 820.
    Airey, John
    et al.
    Department of Physics and Astronomy, Uppsala University.
    Berge, Maria
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Music and physics don't mix!: What the humorous misuse of disciplinary-specific semiotic resources can tell us about disciplinary boundaries2014Conference paper (Refereed)
    Abstract [en]

    Becoming part of an academic discipline has been described both in terms of becoming fluent in a disciplinary discourse (Airey 2009; Airey & Linder 2009; Northedge 2002) and achieving disciplinary literacy (Airey 2011, 2013; Geisler 1994). In this paper we investigate disciplinary boundaries by documenting the responses of academics to a semiotic disciplinary hybrid. The hybrid we use is the Physikalisches Lied, a bogus piece of sheet music into which disciplinary-specific semiotic resources from the realm of physics have been incorporated to humorous effect.

    The piece is presented to three distinct disciplinary focus groups: physicists, musicians and a group of academics who have had little contact with either discipline. In order to elicit disciplinary responses that are free from researcher prompts, each focus group is first asked the simple, open-ended question What do you see here? Once discussion of this question is exhausted the focus groups are asked to identify as many puns as they can - essentially all the disciplinary items that they feel have been misappropriated - and to attempt to explain what this means from a disciplinary standpoint. The differences in the responses of the three groups are presented and analysed.

    We argue that the semiotic resources focused on by each of the three groups and the nature of the explanation offered provide evidence of the degree of integration into the disciplines of physics and music. Our findings shed light on the process of becoming a disciplinary insider and the semiotic work involved in this process.

  • 821.
    Airey, John
    et al.
    Uppsala University.
    Berge, Maria
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    That’s funny!: The humorous effect of misappropriating disciplinary-specific semiotic resources2014Conference paper (Other academic)
    Abstract [en]

    The socialization of disciplinary outsiders into an academic discipline has been described both in terms of becoming fluent in a disciplinary discourse (Airey, 2009; Airey & Linder, 2009; Northedge, 2002) and achieving disciplinary literacy (Airey, 2011, 2013; Geisler, 1994). In this paper we investigate disciplinary boundaries by documenting the responses of academics to a semiotic disciplinary hybrid. The hybrid we use is the Physikalisches Lied, a bogus piece of sheet music into which disciplinary-specific semiotic resources from the realm of physics have been incorporated to humorous effect.

    The piece is presented to three distinct disciplinary focus groups: physicists, musicians and a group of academics who have had little contact with either discipline. In order to elicit disciplinary responses that are free from researcher prompts, each focus group is first asked the simple, open-ended question What do you see here? Once discussion of this question is exhausted the focus groups are asked to identify as many puns as they can—essentially all the disciplinary items that they feel have been misappropriated—and to attempt to explain what this means from a disciplinary standpoint. The differences in the responses of the three groups are presented and analysed.

    We argue that semiotic material focused on by each of the three groups and the nature of the explanation offered, provide evidence of the degree of integration into the disciplines of physics and music. Our findings shed light on the process of becoming a disciplinary insider and the semiotic work involved in this process.

     

    References

    Airey, J. (2009). Science, Language and Literacy. Case Studies of Learning in Swedish University Physics. Acta Universitatis Upsaliensis. Uppsala Dissertations from the Faculty of Science and Technology 81. Uppsala Retrieved 2009-04-27, from http://publications.uu.se/theses/abstract.xsql?dbid=9547

    Airey, J. (2011). The Disciplinary Literacy Discussion Matrix: A Heuristic Tool for Initiating Collaboration in Higher Education. Across the disciplines, 8(3).

    Airey, J. (2013). Disciplinary Literacy. In E. Lundqvist, L. Östman & R. Säljö (eds.), Scientific literacy – teori och praktik (pp. 41-58): Gleerups.

    Airey, J., & Linder, C. (2009). A disciplinary discourse perspective on university science learning: Achieving fluency in a critical constellation of modes. Journal of Research in Science Teaching, 46(1), 27-49.

    Geisler, C. (1994). Academic literacy and the nature of expertise: Reading, writing, and knowing in academic philosophy. Hillsdale, NJ: Erlbaum.

    Northedge, A. (2002). Organizing excursions into specialist discourse communities: A sociocultural account of university teaching. In G. Wells & G. Claxton (eds.), Learning for life in the 21st century. Sociocultural perspectives on the future of education (pp. 252-264). Oxford: Blackwell Publishers.

  • 822.
    Airijoki, Jenny
    Umeå University, Faculty of Social Sciences, Department of applied educational science.
    Vägledning genom sociala medier: Studie- och yrkesvägledares uppfattning om Internet som vägledningsverktyg2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

    Syftet med undersökningen är att beskriva om Internet och sociala medier kan användas inom studie- och yrkesvägledningens verksamhetsområde, men även om det finns problem och hur framtiden kan se ut. Människan är i behov av vägledning genom livet då flera studie- och yrkesrelaterade val genomförs. Denna studie är en kvalitativ semistrukturerad intervjustudie. Studiens mål är att besvara frågeställningarna med hjälp av fem studie- och yrkesvägledare som informanter. Deras erfarenheter och kunskaper ger en bild av hur Internet och Facebook används. Tillsammans med Skolverkets styrdokument, Krumboltz (1999) teori om Planned Happenstance och Peavys (2007) konstruktivistiska vägledning kopplas allt ihop. Resultatet visar att Internet och Facebook som socialt medium utvecklas och användningen av dessa forum i yrkesrollen som studie- och yrkesvägledare varierar från person till person. Många av intervjudeltagarna tror att utvecklingen av dessa forum kommer att fortsätta, men ”face to face” kontakten är fortfarande den viktigaste. Intervjudeltagarna ser Facebook som ett komplement till skolornas lärplattformar och klassinformationen. De tillfrågade studie- och yrkesvägledarna påtalar också att man med hjälp av Facebook och Internet kan förmedla information snabbare till eleverna. Slutsatsen är att den snabba utvecklingen av Internet och sociala medier får en större inverkan på studie- och yrkesvägledarrollen.

  • 823.
    Airijoki, Johan
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Westerdahl, Johanna
    Umeå University, Faculty of Social Sciences, Department of Education.
    Engagemang, nytänkande och ansvar?: En studie av anställdas inställning till LKAB:s värdegrundsarbete.2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den 1 februari år 2012 genomförde LKAB en organisationsförändring som bland annat innefattade införandet av explicita värderingar. Dessa värderingar är engagemang, nytänkande och ansvar vilket sammanfattas till ENA. Värderingarna är framtagna i en process som involverade medarbetarna. Syftet med denna organisationsförändring är, bland annat, att höja attraktionskraften av det egna varumärket, bygga en gemensam företagskultur samt minska avståndet mellan omvärldens uppfattningar och företagets verksamhet. Vi har i denna studie valt att beskriva och analysera hur LKAB:s anställda upplever företagets nylanserade explicita värderingar. Bland de svarande finns det en omfamnande samt en avståndstagande bild till LKAB:s värderingsarbete. De svarande beskriver främst företaget i termer av produktion och ekonomi. Ingen av de svarande beskriver spontant LKAB med orden engagemang, nytänkande och ansvar vilket delvis kan bero på att ENA är en relativt nyligen genomförd organisationsförändring. De två bilder som framgår när de svarande beskriver syftet med ENA-arbetet är dels att det är ord som inte fyller någon funktion och dels att de är ord som har en betydelse i verksamheten.Alla de svarande kände inte till orden. Men bland de svarande som kände till ENA så relaterades orden till allt ifrån att hålla ordning på arbetsutrustningen till företagets historia samt dess framtid.

  • 824. Airoldi, Luisa
    et al.
    Vineis, Paolo
    Colombi, Alessandro
    Olgiati, Luca
    Dell'Osta, Carlo
    Fanelli, Roberto
    Manzi, Luca
    Veglia, Fabrizio
    Autrup, Herman
    Dunning, Alison
    Garte, Seymour
    Hainaut, Pierre
    Hoek, Gerard
    Krzyzanowski, Michal
    Malaveille, Christian
    Matullo, Giuseppe
    Overvad, Kim
    Tjonneland, Anne
    Clavel-Chapelon, Francoise
    Linseisen, Jakob
    Boeing, Heiner
    Trichopoulou, Antonia
    Palli, Domenico
    Peluso, Marco
    Krogh, Vittorio
    Tumino, Rosario
    Panico, Salvatore
    Bueno-De-Mesquita, Hendrik B
    Peeters, Petra H
    Lund, Eiliv
    Agudo, Antonio
    Martinez, Carmen
    Dorronsoro, Miren
    Barricarte, Aurelio
    Chirlaque, M Dolores
    Quiros, Josè R
    Berglund, Goran
    Järvholm, Bengt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Hallmans, Göran
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Nutritional Research.
    Day, Nicholas E
    Allen, Naomi
    Saracci, Rodolfo
    Kaaks, Rudolf
    Riboli, Elio
    4-Aminobiphenyl-hemoglobin adducts and risk of smoking-related disease in never smokers and former smokers in the European Prospective Investigation into Cancer and Nutrition prospective study.2005In: Cancer Epidemiology Biomarkers & Prevention, ISSN 1055-9965, Vol. 14, no 9, p. 2118-24Article in journal (Refereed)
  • 825.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Bechinger, Burkhard
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Macromolecular Crowding at Membrane Interfaces: Adsorption and Alignment of Membrane Peptides2008In: Journal of Molecular Biology, ISSN 0022-2836, E-ISSN 1089-8638, Vol. 375, p. 376-385Article in journal (Refereed)
    Abstract [en]

    Association of proteins to cellular membranes is involved in various biological processes. Various theoretical models have been developed to describe this adsorption mechanism, commonly implying the concept of an ideal solution. However, due to the two-dimensional character of membrane surfaces intermolecular interactions between the adsorbed molecules become important. Therefore previously adsorbed molecules can influence the adsorption behavior of additional protein molecules and their membrane-associated structure. Using the model peptide LAH4, which upon membrane-adsorption can adopt a transmembrane as well as an in-planar configuration, we carried out a systematic study of the correlation between the peptide concentration in the membrane and the topology of this membrane-associated polypeptide. We could describe the observed binding behavior by establishing a concept, which includes intermolecular interactions in terms of a scaled particle theory.

    High surface concentration of the peptide shifts the molecules from an in-planar into a transmembrane conformation, a process driven by the reduction of occupied surface area per molecule. In a cellular context, the crowding-dependent alignment might provide a molecular switch for a cell to sense and control its membrane occupancy. Furthermore, crowding might have pronounced effects on biological events, such as the cooperative behavior of antimicrobial peptides and the membrane triggered aggregation of amyloidogenic peptides.

  • 826.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Chemistry.
    Bertani, Philippe
    Henklein, Peter
    Bechinger, Burkhard
    Structure, dynamics and topology of membrane polypeptides by oriented 2H solid-state NMR spectroscopy2007In: European Biophysics Journal, ISSN 0175-7571 (Print) 1432-1017 (Online), Vol. 36, no 4-5, p. 451-60Article in journal (Refereed)
    Abstract [en]

    Knowledge of the structure, dynamics and interactions of polypeptides when associated with phospholipid bilayers is key to understanding the functional mechanisms of channels, antibiotics, signal- or translocation peptides. Solid-state NMR spectroscopy on samples uniaxially aligned relative to the magnetic field direction offers means to determine the alignment of polypeptide bonds and domains relative to the bilayer normal. Using this approach the 15N chemical shift of amide bonds provides a direct indicator of the approximate helical tilt, whereas the 2H solid-state NMR spectra acquired from peptides labelled with 3,3,3-2H3-alanines contain valuable complimentary information for a more accurate analysis of tilt and rotation pitch angles. The deuterium NMR line shapes are highly sensitive to small variations in the alignment of the Cα–Cβ bond relative to the magnetic field direction and, therefore, also the orientational distribution of helices relative to the membrane normal. When the oriented membrane samples are investigated with their normal perpendicular to the magnetic field direction, the rate of rotational diffusion can be determined in a semi-quantitative manner and thereby the aggregation state of the peptides can be analysed. Here the deuterium NMR approach is first introduced showing results from model amphipathic helices. Thereafter investigations of the viral channel peptides Vpu1–27 and Influenza A M222–46 are shown. Whereas the 15N chemical shift data confirm the transmembrane helix alignments of these hydrophobic sequences, the deuterium spectra indicate considerable mosaic spread in the helix orientations. At least two peptide populations with differing rotational correlation times are apparent in the deuterium spectra of the viral channels suggesting an equilibrium between monomeric peptides and oligomeric channel configurations under conditions where solid-state NMR structural studies of these peptides have previously been performed.

  • 827.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Chemistry.
    Borowik, Tomasz
    Byström, Roberth
    Umeå University, Faculty of Science and Technology, Chemistry.
    Bokvist, Marcus
    Umeå University, Faculty of Science and Technology, Chemistry.
    Lindström, Fredrick
    Umeå University, Faculty of Science and Technology, Chemistry.
    Misiak, Hanna
    Sani, Marc-Antoine
    Umeå University, Faculty of Science and Technology, Chemistry.
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Chemistry.
    How is protein aggregation in amyloidogenic diseases modulated by biological membranes?2008In: European Biophysics Journal, ISSN 0175-7571, E-ISSN 1432-1017, European Biophysics Journal, ISSN 1432-1017 (Online), Vol. 37, no 3, p. 247-55Article in journal (Refereed)
    Abstract [en]

    The fate of proteins with amyloidogenic properties depends critically on their immediate biochemical environment. However, the role of biological interfaces such as membrane surfaces, as promoters of pathological aggregation of amyloidogenic proteins, is rarely studied and only established for the amyloid-β protein (Aβ) involved in Alzheimer’s disease, and α-synuclein in Parkinsonism. The occurrence of binding and misfolding of these proteins on membrane surfaces, is poorly understood, not at least due to the two-dimensional character of this event. Clearly, the nature of the folding pathway for Aβ protein adsorbed upon two-dimensional aggregation templates, must be fundamentally different from the three-dimensional situation in solution. Here, we summarize the current research and focus on the function of membrane interfaces as aggregation templates for amyloidogenic proteins (and even prionic ones). One major aspect will be the relationship between membrane properties and protein association and the consequences for amyloidogenic products. The other focus will be on a general understanding of protein folding pathways on two-dimensional templates on a molecular level. Finally, we will demonstrate the potential importance of membrane-mediated aggregation for non-amphiphatic soluble amyloidogenic proteins, by using the SOD1 protein involved in the amyotrophic lateral sclerosis syndrome.

  • 828.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Byström, Roberth
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Oliveberg, Mikael
    Department of Biochemistry and Biophysics, Stockholm University, 10691 Stockholm, Sweden.
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    SOD1 associates to membranes in its folded apo-stateManuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease accompanied by misfolding and intracellular deposition of superoxide dismutase 1 (SOD1). Although the molecular details behind this misfolding process are yet poorly understood, increasing evidence suggest that SOD1 is most susceptible to misfolding in its metal-free and relatively unstable apo-state. Here, we addressed the question, if misfolding and aggregation of SOD1 involves erroneous interactions with membranes as has been implicated for the Aβ peptide in Alzheimers disease. To examine this possibility we subjected various apo SOD1 variants to the presence of different membrane systems. The results reveal that wild type apoSOD1 but to less extent destabilized ALS mutations interact with charged vesicles under physiologically relevant conditions, thereby acquiring pronounced helical structural features. As the data further show, the protein binds to the membranes by an electrostatically driven mechanism, which requires a folded apo-state conformation and a negative membrane surface potential. Unfolded SOD1 molecules show no appreciable affinity to the membrane surfaces yielding a correlation between increased stability, i. e. occupancy of folded molecules and extend of membrane association. Since this trend opposes the correlation between decreased SOD1 stability and progression of neural damage, the results suggest that membrane association is not part of the ALS mechanism. An explanation could be that the observed membrane association of apo SOD1 is reversible and does not ‘bleed out’ in irreversible aggregation as observed for other precursors of protein-misfolding diseases.

  • 829.
    Aisenbrey, Christopher
    et al.
    Institut de Chimie Universit0 Louis Pasteur Strasbourg—CNRS, UMR 7177 4, Rue Blaise Pascal, 67000 Strasbourg (France); Max-Planck-Institut f>r Biochemie Am Klopferspitz 18A, 82152 Martinsried (Germany).
    Cusan, Monica
    Lambotte, Stephan
    Jasperse, Pieter
    Georgescu, Julia
    Harzer, Ulrike
    Bechinger, Burkhard
    Specific Isotope Labeling of Colicin E1 and B Channel Domains For Membrane Topological Analysis by Oriented Solid-State NMR Spectroscopy2008In: ChemBioChem (Print), ISSN 1439-4227, E-ISSN 1439-7633, Vol. 9, no 6, p. 944-951Article in journal (Refereed)
    Abstract [en]

    An approach is presented to selectively label the methionines of the colicin E1 and B channel domains, each about 200 residues in size, and use them for oriented solid-state NMR investigations. By combining site-directed mutagenesis, bacterial overexpression in a methionine auxotroph E. coli strain and biochemical purification, quantitative amounts of the proteins for NMR structural investigations were obtained. The proteins were selectively labeled with 15N at only one, or at a few, selected sites. Multidimensional heteronuclear correlation high-resolution NMR spectroscopy and mass spectrometry were used to monitor the quality of isotopic labeling. Thereafter the proteins were reconstituted into oriented phospholipid bilayers and investigated by proton-decoupled 15N solid-state NMR spectroscopy. The colicin E1 thermolytic fragment that carries a single 15N methionine within its hydrophobic helix 9 region exhibited 15N resonances that are characteristic of helices that are oriented predominantly parallel to the membrane surface at low temperature, and a variety of alignments and conformations at room temperature. This suggests that the protein can adopt both umbrella and pen-knife conformations.

  • 830.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Chemistry.
    Sizun, Christina
    Koch, Joachim
    Herget, Meike
    Abele, Rupert
    Bechinger, Burkhard
    Tampé, Robert
    Structure and dynamics of membrane-associated ICP47, a viral inhibitor of the MHC I antigen-processing machinery2006In: The Journal of Biological Chemistry, ISSN 0021-9258, Vol. 281, no 41, p. 30365-72Article in journal (Refereed)
    Abstract [en]

    To evade the host's immune response, herpes simplex virus employs the immediate early gene product ICP47 (IE12) to suppress antigen presentation to cytotoxic T-lymphocytes by inhibition of the ATP-binding cassette transporter associated with antigen processing (TAP). ICP47 is a membrane-associated protein adopting an alpha-helical conformation. Its active domain was mapped to residues 3-34 and shown to encode all functional properties of the full-length protein. The active domain of ICP47 was reconstituted into oriented phospholipid bilayers and studied by proton-decoupled 15N and 2H solid-state NMR spectroscopy. In phospholipid bilayers, the protein adopts a helix-loop-helix structure, where the average tilt angle of the helices relative to the membrane surface is approximately 15 degrees (+/- 7 degrees ). The alignment of both structured domains exhibits a mosaic spread of approximately 10 degrees . A flexible dynamic loop encompassing residues 17 and 18 separates the two helices. Refinement of the experimental data indicates that helix 1 inserts more deeply into the membrane. These novel insights into the structure of ICP47 represent an important step toward a molecular understanding of the immune evasion mechanism of herpes simplex virus and are instrumental for the design of new therapeutics.

  • 831.
    Aisenbrey, Christopher
    et al.
    Umeå University, Faculty of Science and Technology, Chemistry.
    Sudheendra, U. S.
    Ridley, Helen
    Bertani, Philippe
    Marquette, Arnaud
    Nedelkina, Svetlana
    Lakey, Jeremy H.
    Bechinger, Burkhard
    Helix orientations in membrane-associated Bcl-XL determined by 15N-solid-state NMR spectroscopy2007In: European Biophysics Journal, ISSN 0175-7571 (Print) 1432-1017 (Online), Vol. 37, no 1, p. 71-80Article in journal (Refereed)
    Abstract [en]

    Controlled cell death is fundamental to tissue hemostasis and apoptosis malfunctions can lead to a wide range of diseases. Bcl-xL is an anti-apoptotic protein the function of which is linked to its reversible interaction with mitochondrial outer membranes. Its interfacial and intermittent bilayer association makes prediction of its bound structure difficult without using methods able to extract data from dynamic systems. Here we investigate Bcl-xL associated with oriented lipid bilayers at physiological pH using solid-state NMR spectroscopy. The data are consistent with a C-terminal transmembrane anchoring sequence and an average alignment of the remaining helices, i.e. including helices 5 and 6, approximately parallel to the membrane surface. Data from several biophysical approaches confirm that after removal of the C-terminus from Bcl-xL its membrane interactions are weak. In the presence of membranes Bcl-xL can still interact with a Bak BH3 domain peptide suggesting a model where the hydrophobic C-terminus of the protein unfolds and inserts into the membrane. During this conformational change the Bcl-xL hydrophobic binding pocket becomes accessible for protein–protein interactions whilst the structure of the N-terminal region remains intact.

  • 832. Aitio, Antero
    et al.
    Bernard, Alfred
    Fowler, Bruce A.
    Nordberg, Gunnar F.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Environmental Medicine.
    Biological Monitoring and Biomarkers2007In: Handbook on the Toxicology of Metals, 3rd Edition / [ed] Gunnar F. Nordberg, Bruce A. Fowler, Monica Nordberg and Lars T. Friberg, San Diego: Elsevier, 2007, 3, p. 65-78Chapter in book (Other academic)
    Abstract [en]

    Biomonitoring was developed for the assessment of the health risks from exposure to metals at work, and the approaches and concepts of biomonitoring are derived from such exposures. At present, biomonitoring is increasingly used to assess exposure from the environment. Biomonitoring and assessment of external exposure are complementing activities, where the exposure assessments are much more widely applied, especially when the number of chemicals concerned is considered; environmental analysis also offers the distinct advantage of speciation analysis, which is very poorly developed for biomonitoring. Biomonitoring, on the other hand, provides information on exposure from all sources, and via all absorption routes, and also considers accumulation of the chemical in the body. Biomonitoring using exposure biomarkers thus considers interindividual differences in the absorption, whereas use of effect biomarkers also considers interindividual differences in sensitivity. Few effect biomarkers, however, have been validated. Biomarkers of susceptibility have so far not been adapted for use in metal toxicology. The major challenges of biomonitoring are the development of monitoring methods, which are inexpensive enough to be applied at a frequency that makes possible meaningful biomonitoring of metals with a short half-time; development of exposure biomarker guidance values specific to individual species of different metals; expansion of the repertoire of validated effect biomarkers; and validation and application to effect monitoring of the "omic" technologies.

  • 833.
    Aittamaa, Johan
    et al.
    Umeå University, Faculty of Social Sciences, Basic training programme for Police Officers.
    Årbro, Eva
    Umeå University, Faculty of Social Sciences, Basic training programme for Police Officers.
    Säkerheten vid Luleå Hockeys matcher2008Independent thesis Basic level (professional degree), 5 credits / 7,5 HE creditsStudent thesis
    Abstract [sv]

    I denna rapport tar vi upp ansvarsfrågan kring säkerhetsarbetet vid Luleå Hockeys hemmamatcher i Coop arena. Vi har genom att studera lagtext, intervjua företrädare från polisen, Luleå Hockey och LuleåFans, Luleå Hockeys supporterklubb, försökt skapa oss en bild av dels hur det juridiska ansvaret fördelas och dels hur samarbetet fungerar de olika aktörerna emellan. Enligt ordningslagen har Luleå Hockey ansvaret för säkerheten i Coop arena. Polisen är alltid närvarande vid matcher och har även extra bevakning vid derbymatcher mellan Luleå Hockey och Skellefteå AIK. Denna bevakning behöver dock inte Luleå Hockey betala något för eftersom de är en ideell förening. I arbetet har vi kommit fram till att problemen inte alls var så stora som vi trodde men att det trots allt finns en del problem, framför allt tycker både Luleå Hockeys säkerhetsansvarige och LuleåFans talesperson att Luleå Hockeys ledning inte prioriterar säkerhetsfrågorna tillräckligt mycket. I arbetet framkommer också kritik mot lagen om tillträdesförbud vid idrottsarrangemang som är både krånglig och svår att tillämpa som den är utformad i dagsläget.

  • 834.
    Aittamaa, Jonas
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Senning, Magnus
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Outsourcing & Insourcing: Vad ligger bakom företagens beslut?2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    SAMMANFATTNING

    Karaktäristiskt för dagens företagsvärld är omvärldsförändringar och ständiga fluktuationer på marknaden. Större krav på företags effektivitet är numera ett faktum i och med den stadigt växande konkurrensen. Innovation, flexibilitet och framförallt att vara snabb i utvecklingen för att kunna bibehålla sin ställning och tillfredställa kundernas behov är alla aspekter som har kommit att bli allt viktigare. För att lyckas med detta har många företag valt att inrikta sig mot det som man inom företag anser vara sin kärnverksamhet, det vill säga den interna kompetens som gör företag unika och som differentierar dem från konkurrenter. Outsourcing har därför kommit att bli ett organisationsfenomen som möjliggör detta.

    Med outsourcing menas; ”den process som innebär att aktiviteter som bildar en funktion och som tidigare utförts internt inom företaget, istället köps från en extern leverantör”.

    Dock visar forskning på att så mycket som 60 procent av alla outsourcingprojekt misslyckas. Detta grundar sig på det faktum att alltför många företag börjat utkontraktera delar av verksamheten med bristande förståelse om vilka negativa effekter som kan uppstå. Detta har medfört att många företag börjat ifrågasätta sin egen outsourcingstrategi vilket i sin tur lett till att tidigare utkontrakterade funktioner återförs till verksamheten, det vill säga att funktionerna insourcas.

    Vi har valt att genomföra en kvalitativ studie med målet att försöka svara på varför företag valt att outsourca delar av verksamheten för att därefter granska vilka motiv som föreligger för att insourca de tidigare utkontrakterade delarna. Vidare har vi även använt oss av en hermeneutisk kunskapssyn och ett deduktivt angreppssätt.

    Teoriavsnittet innehåller totalt sju delar som behandlar vårt problem. Den första delen tar upp beslutet om köp eller egentillverkning. Den andra handlar om kärnkompetens. De fyra efterföljande delarna behandlar fenomenet outsourcing, eller mer specifikt vad det innebär, motiv, risker och avslutningsvis outsourcingprocessen. Den sjunde och sista delen behandlar innebörden samt risker och fördelar med insourcing.

    I empirikapitlet presenteras sammanställningen av de fyra intervjuer som vi utfört i vår empiriska studie. För att på bästa sätt kunna tydliggöra respondenternas åsikter följer dispositionen i detta avsnitt en likvärdig struktur som dispositionen i teoriavsnittet.

    Det insamlade materialet från empirin sammankopplas i analysavsnittet till teorin. Vi ser att motiven till outsourcing kan delas in i två faktorer, kostnadseffektivisering och fokusering på kärnverksamheten. Vidare väljer företag att återinföra tidigare utkontrakterade funktioner i verksamheten i huvudsak beroende på låg kvalitet från leverantören och att den ekonomiska vinningen av att outsourca verksamheten inte motsvarat förväntningarna. Vår slutsats av detta är att dåligt förarbete och beslutsunderlag vid outsourcing är en anledning till insourcing. En annan är omvärldsförändringar som kan innebära skillnader i de ekonomiska förutsättningarna.

  • 835.
    Aittamaa, Lina
    et al.
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    Ek, Linda
    Umeå University, Faculty of Social Sciences, Department of Psychology.
    "Det är väl mest jag själv som är problemet"Berättelser om nedstämdhet2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Forskare har påpekat vikten av att förstå erfarenheter av att vara deprimerad eller nedstämd. I linje med detta syftade denna studie till att undersöka och belysa upplevelser av och reflektioner kring vardagen som nedstämd. Vidare var syftet att visa på kulturella resurser (diskurser) som finns tillgängliga för att berätta om en vardag som nedstämd. Vi genomförde halvstrukturerade intervjuer med personer som sökt till ett behandlingsprogram för depression, och som därmed definierat sig själva som nedstämda. Vi analyserade 28 intervjuer med hjälp av tematisk analys och diskursanalytiska metoder. Vi fann att informanterna använde sig av åtminstone fem olika typer av förklaringar som kretsade kring tidiga erfarenheter, personlighet, livskris, eget ansvar och biologi. Vidare fann vi att berättelserna kring nedstämdheten på flera sätt kunde beröra hur levnadssituationen hos informanterna såg ut. Ofta var dock levnadssituationen på samma gång helt frånvarande när det kom till att förklara nedstämdheten. Vårt resultat visade att individfokuserade diskurser var dominerande för att berätta om nedstämdhet, medan diskurser med fokus på yttre omständigheter, exempelvis livssituation, var marginaliserade.

  • 836.
    Aizsalnieks, Janis
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Sustainable development strategy in the EU and Latvia-comparative study2003Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 837.
    Ajaikumar, Samikannu
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ahlkvist, Johan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Larsson, William
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Kordas, K
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Highly active and selective bimetallic catalysts supported on transition metal oxides for the oxidation of α-pinene using molecular oxygen2010Conference paper (Other academic)
  • 838.
    Ajaikumar, Samikannu
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ahlkvist, Johan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Larsson, William
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kordas, K
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Synthesis and characterization of Cu and Cu-M (M=Co, Ni, Au and Zn) bimetallic catalysts supported on TiO2 modified SBA-152010Conference paper (Other academic)
  • 839.
    Ajaikumar, Samikannu
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ahlkvist, Johan
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Larsson, William
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kordas, K
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry Centre, Åbo Akademi University, Piispankatu 8, FIN-20500, Turku/Åbo, Finland.
    Oxidation of α-pinene over gold containing bimetallic nanoparticles supported on reducible TiO2 by DPU method2011In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 392, no 1-2, p. 11-18Article in journal (Refereed)
    Abstract [en]

    A series of bimetallic catalysts Au–M (where M = Cu, Co and Ru) were supported on a reducible TiO2 oxide via deposition-precipitation (DP) method with a slow decomposition of urea as the precipitating agent. The characteristic structural features of the prepared materials were characterized by various physico-chemical techniques such as X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). XPS results indicated the formation of alloyed bimetallic particles on the TiO2 support. TEM results confirmed the fine dispersion of metal nanoparticles on the support with an average particle size in the range of 3–5 nm. An industrially important process, oxy-functionalization of α-pinene was carried out over the prepared bimetallic heterogeneous catalysts under liquid phase conditions. Reaction parameters such as the reaction time, temperature, and the effect of solvent were studied for optimal conversion of α-pinene into verbenone. The major products obtained were verbenone, verbenol, α-pinene oxide and alkyl-pinene peroxide. The activity of the catalysts followed the order; AuCu/TiO2 > AuCo/TiO2 > Cu/TiO2 > Au/TiO2 > AuRu/TiO2. Upon comparison of the various catalysts, AuCu/TiO2 was found to be an active and selective catalyst towards the formation of verbenone. The temperature, nature of the catalysts and the choice of solvents greatly influenced the reaction rate.

  • 840.
    Ajaikumar, Samikannu
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Chemistry, Anna University, Guindy, Chennai, India.
    Backiaraj, Muthaiah
    Mikkola, Jyri-Pekka
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry Centre, Åbo Akademi University, Turku/Åbo, Finland.
    Pandurangan, Arumugam
    Transesterification of diethyl malonate with n-butanol over HPWA/MCM-41 molecular sieves2013In: Journal of porous materials, ISSN 1380-2224, E-ISSN 1573-4854, Vol. 20, no 4, p. 951-959Article in journal (Refereed)
    Abstract [en]

    Mesoporous Si-MCM-41 and Al-MCM-41 (Si/Al = 100) materials were synthesized via a hydrothermal method. Three different ratios (10, 20 and 30 wt%) of heteropoly tungstic acid (HPWA) was loaded on Si-MCM-41 by wet impregnation techniques. The characteristic structural features of the prepared materials were studied by various physico-chemical techniques such as X-ray diffraction (XRD), Nitrogen physisorption (BET), temperature programmed desorption of ammonia (TPD) and transmission electron microscopy (TEM). Transesterification of diethyl malonate (DEM) with n-butanol under autogeneous conditions in a temperature range from 50 to 125 °C was selected as the test reaction for the as synthesized materials. The reactants were fed with various mole ratios in order to determine the optimal feed composition leading to maximum yields of transesterified products. The results indicated that the conversion of diethylmalonate depends on the HPWA concentration on the support, temperature, reaction time and mole ratio of the reactants. Further, the catalytic efficiency of HPWA/MCM-41 was compared with that of Al-MCM-41. The solid acid HPWA/MCM-41 catalysts have several advantages in comparison to conventional mineral acid catalysts which are heterogeneous, eco-friendly, highly active and selective in the formation of transesters.

  • 841.
    Ajami, Nina
    et al.
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Coffey, Christina
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Lewén-Johansson, Birgitta
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Äldre som aktiva IT-användare? – En studie av ålderspensionärers inställning till datoranvändning.2000Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 842.
    Ajami, Nina
    et al.
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Trillkott, Magnus
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Virtuella världar - En studie om virtuellt varandeIndependent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 843.
    Ajang, Peter Ebong
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Assessing the role of work Motivation on Employee Performance2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The main purpose of this study was to” assess the role of work motivation on employee performance”. This study in an assessment of this purpose used deductive approach in which a qualitative survey was carried out among students at of Umeå Business School (USBE) who are assumed to be future employees .The survey was intended to get their responses on what they feel is (are) the best factors that could motivate them as future employees among a list of ten motivational factors. In this light the study sets to identify the most ranked factors among the ten motivational factors.

    The analysis from the empirical findings showed that Job satisfaction”was the most ranked factor for both sub groups that made up the sample survey. However a study from previous researches used in this study showed that different results could be obtained from different groups of already working employees. This study therefore can be seen as an introduction to a more detailed study to be carried by future researchers on the field of employee’s motivation.

  • 844.
    Ajang, Peter Ebong
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    Njofor, Victorine Numfor
    Umeå University, Faculty of Social Sciences, Umeå School of Business.
    An Assessment of Market Growth Strategies in a multinational company: The case of Komatsu Forest AB2007Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Setting strategies for an organisation is full of complexities (which strategy or strategic process to use) and these complexities arise from the ambiguous and non-routine processes. This is so because, strategy development is about the future and this future is unknown, as the paths companies follow are dynamic. Due to these complexities, managers tend to embark on knowledge gain through competencies in the management of companies. In order for future managers who have not had organisational experience to understand how strategic management is in real company situation, a case study on the types of market growth strategies and strategy development process in a multinational company is done in this thesis. How these strategies implemented affects market share is also an elaborate part of this study

    This study was done as a case study in Komatsu Forest AB; a multinational company that manufactures forestry machines. In this light, the study sets to identify the market growth strategies implemented by this company, its strategy development process and how the strategies have affected its market share.

    As basis for an empirical research process, a theoretical framework was compiled from existing literatures on market growth strategies and strategy development process, where the strategies were considered both at the business level and corporate level. A deduction research approach was appropriate for the study whereby qualitative empirical data was collected through semi-structured face-to-face interviews. The interviews were conducted with two employees of the company (Market analyst and the spokesman for the company) who were considered to be knowledgeable in the subject area. This allowed a thorough understanding of particular issues pertaining to the company.

    The analysis of the empirical findings showed that this company implements acquisition, partnership/networks and diversification at the corporate level and high pricing, differentiation at the business level as its market growth strategies. This company develops these strategies through a planned process; meaning that strategies are intended and these strategies have a positive impact on the company as its overall market situation has increased. This study offer some contributions for this company on how some strategic adjustments can be made in order to improve the current market situation and some recommendations for its management in better decision making.

  • 845.
    Ajdinovic, Dzejla
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Resonemang och problemlösning i Matematik 1b: En uppgiftsanalys av två läroböcker2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Studien undersökte möjligheten att utveckla problemlösnings- och resonemangsförmåga i svenska läroböcker. Under studiens gång genomfördes en läromedelsanalys av två läroböcker för gymnasiekursen Matematik 1b, Matematik 5000 och Matematik Origo. Analysen tog hänsyn till olika aspekter av förmågorna, olika svårighetsgrader på uppgifterna samt olika centralt innehåll i ämnesplanen. Av 2223 uppgifter i Matematik 5000 kunde problemlösningsförmågan utvecklas i 5% och resonemangsförmågan i 6%. Motsvarande andelar i 1747 uppgifter i Matematik Origo var 7% respektive 10%. Analysen visade också att större andel av uppgifterna på de två högre svårighetsnivåerna gav möjlighet att utveckla förmågorna än de på den lägsta nivån i båda böckerna. Det framkom även att inte alla aspekter av förmågorna fick lika stort utrymme att utvecklas. I båda böckerna var det geometri-kapitlet som fokuserade på dessa förmågor i störst andel av uppgifterna.

  • 846. Ajeani, Judith
    et al.
    Ayiasi, Richard Mangwi
    Tetui, Moses
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. Makerere University School of Public Health (MakSPH), Makerere University College of Health Sciences, Kampala, Uganda.
    Ekirapa-Kiracho, Elizabeth
    Namazzi, Gertrude
    Kananura, Rornald Muhumuza
    Kiwanuka, Suzanne Namusoke
    Beyeza-Kashesya, Jolly
    A cascade model of mentorship for frontline health workers in rural health facilities in Eastern Uganda: processes, achievements and lessons2017In: Global Health Action, ISSN 1654-9716, E-ISSN 1654-9880, Vol. 10, article id 1345497Article in journal (Refereed)
    Abstract [en]

    Background: There is increasing demand for trainers to shift from traditional didactic training to innovative approaches that are more results-oriented. Mentorship is one such approach that could bridge the clinical knowledge gap among health workers.

    Objectives: This paper describes the experiences of an attempt to improve health-worker performance in maternal and newborn health in three rural districts through a mentoring process using the cascade model. The paper further highlights achievements and lessons learnt during implementation of the cascade model.

    Methods: The cascade model started with initial training of health workers from three districts of Pallisa, Kibuku and Kamuli from where potential local mentors were selected for further training and mentorship by central mentors. These local mentors then went on to conduct mentorship visits supported by the external mentors. The mentorship process concentrated on partograph use, newborn resuscitation, prevention and management of Post-Partum Haemorrhage (PPH), including active management of third stage of labour, preeclampsia management and management of the sick newborn. Data for this paper was obtained from key informant interviews with district-level managers and local mentors.

    Results: Mentorship improved several aspects of health-care delivery, ranging from improved competencies and responsiveness to emergencies and health-worker professionalism. In addition, due to better district leadership for Maternal and Newborn Health (MNH), there were improved supplies/medicine availability, team work and innovative local problem-solving approaches. Health workers were ultimately empowered to perform better.

    Conclusions: The study demonstrated that it is possible to improve the competencies of frontline health workers through performance enhancement for MNH services using locally built capacity in clinical mentorship for Emergency Obstetric and Newborn Care (EmONC). The cascade mentoring process needed strong external mentorship support at the start to ensure improved capacity among local mentors to provide mentorship among local district staff.

  • 847. Ajob, Leith
    et al.
    Brännström, Ingrid
    Ott, Michael
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Werneke, Ursula
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Psychiatry. Fellow of the Royal College of Psychiatrists (FRCPsych).
    ABC om Wernickes encefalopati2017In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 114, no ELZTArticle in journal (Refereed)
  • 848. Ajroud-Driss, Senda
    et al.
    Adams, David
    Coelho, Teresa
    Polydefkis, Michael
    Gonzalez-Duarte, Alejandra
    Quan, Dianna
    Kristen, Arnt
    Berk, John
    Agarwal, Sonalee
    Partisano, Angela
    Gollob, Jared
    Sweester, Marianne
    Chen, Jihong
    Suhr, Ole B.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Impact of Patisiran on overall health status in hATTR amyloidosis: Results from the APOLLO trial2018In: Journal of the peripheral nervous system, ISSN 1085-9489, E-ISSN 1529-8027, Vol. 23, no 4, p. 272-273Article in journal (Other academic)
  • 849. Ajroud-Driss, Senda
    et al.
    Adams, David
    Coelho, Teresa
    Polydefkis, Michael
    Gonzalez-Duarte, Alejandra
    Quan, Dianna
    Kristen, Arnt
    Berk, John L.
    Partisano, Angela M.
    Gollob, Jared
    Sweetser, Marianne T.
    Chen, Jihong
    Agarwal, Sonalee
    Suhr, Ole B.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.
    Impact of Patisiran on Overall Health Status in hATTR Amyloidosis: Results from the APOLLO Trial2019In: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 92, no 15Article in journal (Other academic)
  • 850. Ajuria, Jon
    et al.
    Arnaiz, Maria
    Botas, Cristina
    Carriazo, Daniel
    Mysyk, Roman
    Rojo, Teofilo
    Talyzin, Alexandr V.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Goikolea, Eider
    Graphene-based lithium ion capacitor with high gravimetric energy and power densities2017In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 363, p. 422-427Article in journal (Refereed)
    Abstract [en]

    Hybrid capacitor configurations are now of increasing interest to overcome the current energy limitations of supercapacitors. In this work, we report a lithium ion capacitor (LIC) entirely based on graphene. On the one hand, the negative-battery-type- electrode consists of a self-standing, binder-free 3D macroporous foam formed by reduced graphene oxide and decorated with tin oxide nanoparticles (SnO2-rGO). On the other hand, the positive-capacitor-type- electrode is based on a thermally expanded and physically activated reduced graphene oxide (a-TEGO). For comparison purposes, a symmetric electrical double layer capacitor (EDLC) using the same activated graphene in 1.5 M Et4NBE4/ACN electrolyte is also assembled. Built in 1 M LiPF6 EC:DMC, the graphene-based LIC shows an outstanding, 10-fold increase in energy density with respect to its EDLC counterpart at low discharge rates (up to 200 Wh kg(-1)). Furthermore, it is still capable to deliver double the energy in the high power region, within a discharge time of few seconds.

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