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  • 104651. Roy, Bitan
    et al.
    Juricic, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Optical conductivity of an interacting Weyl liquid in the collisionless regime2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 96, no 15, article id 155117Article in journal (Refereed)
    Abstract [en]

    Optical conductivity (OC) can serve as a measure of correlation effects in a wide range of condensed-matter systems. We show that the long-range tail of the Coulomb interaction yields a universal correction to the OC in a three-dimensional Weyl semimetal sigma(Omega) = sigma(0)(Omega)[1 + 1/N+1], where sigma(0)(Omega) = Ne-0(2)Omega/(12hv) is the OC in the noninteracting system, with v as the actual (renormalized) Fermi velocity of Weyl quasiparticles at frequency Omega, and e(0) is the electron charge in vacuum. Such universal enhancement of OC, which depends only on the number of Weyl nodes near the Fermi level (N), is a remarkable consequence of an intriguing conspiracy among the quantum-critical nature of an interacting Weyl liquid, marginal irrelevance of the long-range Coulomb interaction, and violation of hyperscaling in three dimensions, and can directly be measured in recently discovered Weyl as well as Dirac materials. By contrast, a local density-density interaction produces a nonuniversal correction to the OC, stemming from the nonrenormalizable nature of the corresponding interacting field theory.

  • 104652. Roy, Bitan
    et al.
    Juricic, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Unconventional superconductivity in nearly flat bands in twisted bilayer graphene2019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 12, article id 121407Article in journal (Refereed)
    Abstract [en]

    Flat electronic bands can accommodate a plethora of interaction-driven quantum phases, since kinetic energy is quenched therein and electronic interactions therefore prevail. Twisted bilayer graphene, near the so-called magic angles, features slow Dirac fermions close to the charge-neutrality point that persist up to high energies. Starting from a continuum model of slow but strongly interacting Dirac fermions, we show that with increasing chemical doping away from the charge-neutrality point, a time-reversal symmetry breaking, valley pseudospin-triplet, topological p + ip superconductor gradually sets in, when the system resides at the brink of an antiferromagnetic ordering (due to Hubbard repulsion), in qualitative agreement with recent experimental findings. The p ip paired state exhibits quantized spin and thermal Hall conductivities, and polar Kerr and Faraday rotations. Our conclusions should also be applicable for other correlated two-dimensional Dirac materials.

  • 104653. Roy, Bitan
    et al.
    Juricic, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita). Utrecht University, The Netherlands.
    Herbut, Igor F.
    Emergent Lorentz symmetry near fermionic quantum critical points in two and three dimensions2016In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, no 4, article id 018Article in journal (Refereed)
    Abstract [en]

    We study the renormalization group flow of the velocities in the field theory describing the coupling of the massless quasi-relativistic fermions to the bosons through the Yukawa coupling, as well as with both bosons and fermions coupled to a fluctuating U(1) gauge field in two and three spatial dimensions. Different versions of this theory describe quantum critical behavior of interacting Dirac fermions in various condensed matter systems. We perform an analysis using one-loop 6-expansion about three spatial dimensions, which is the upper critical dimension in the problem. In two dimensions, we find that velocities of both charged fermions and bosons ultimately flow to the velocity of light, independently of the initial conditions, the number of fermionic and bosonic flavors, and the value of the couplings at the critical point. In three dimensions, due to the analyticity of the gauge field propagator, both the U(1) charge and the velocity of light flow, which leads to a richer behavior than in two dimensions. We show that all three velocities ultimately flow to a common terminal velocity, which is non-universal and different from the original velocity of light. Therefore, emergence of the Lorentz symmetry in the ultimate infrared regime seems to be a rather universal feature of this class of theories in both two and three dimensions.

  • 104654. Roy, Bitan
    et al.
    Juricic, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Sarma, Sankar Das
    Universal optical conductivity of a disordered Weyl semimetal2016In: Scientific Reports, E-ISSN 2045-2322, Vol. 6, article id 32446Article in journal (Refereed)
    Abstract [en]

    Topological Weyl semimetals, besides manifesting chiral anomaly, can also accommodate a disorder-driven unconventional quantum phase transition into a metallic phase. A fundamentally and practically important question in this regard concerns an experimentally measurable quantity that can clearly distinguish these two phases. We show that the optical conductivity while serving this purpose can also play the role of a bonafide order parameter across such disorder-driven semimetal-metal quantum phase transition by virtue of displaying distinct scaling behavior in the semimetallic and metallic phases, as well as inside the quantum critical fan supporting a non-Fermi liquid. We demonstrate that the correction to the dielectric constant and optical conductivity in a dirty Weyl semimetal due to weak disorder is independent of the actual nature of point-like impurity scatterers. Therefore, optical conductivity can be used as an experimentally measurable quantity to study the critical properties and to pin the universality class of the disorder-driven quantum phase transition in Weyl semimetals.

  • 104655. Roy, Bitan
    et al.
    Juričić, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Collisionless Transport Close to a Fermionic Quantum Critical Point in Dirac Materials2018In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 121, no 13, article id 137601Article in journal (Refereed)
    Abstract [en]

    Quantum transport close to a critical point is a fundamental, but enigmatic problem due to fluctuations, persisting at all length scales. We report the scaling of optical conductivity (OC) in the collisionless regime ((sic)omega >> k(B)T) in the vicinity of a relativistic quantum critical point, separating two-dimensional (d = 2) massless Dirac fermions from a fully gapped insulator or superconductor. Close to such a critical point, gapless fermionic and bosonic excitations are strongly coupled, leading to a universal suppression of the interband OC as well as of the Drude peak (while maintaining its delta function profile) inside the critical regime, which we compute to the leading order in 1/N-f- and epsilon expansions, where N-f counts the fermion flavor number and epsilon = 3 - d. Correction to the OC at such a non-Gaussian critical point due to the longrange Coulomb interaction and generalizations of these scenarios to a strongly interacting three-dimensional Dirac or Weyl liquid are also presented, which can be tested numerically and possibly from nonperturbative gauge-gravity duality, for example.

  • 104656. Roy, Bitan
    et al.
    Juričić, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Correlated fractional Dirac materials2023In: Physical Review Research, E-ISSN 2643-1564, Vol. 5, no 3, article id L032002Article in journal (Refereed)
    Abstract [en]

    Fractional Dirac materials (FDMs) feature a fractional energy-momentum relation E(k) <^> |k|& alpha;, where & alpha; (< 1) is a real noninteger number, in contrast to that in conventional Dirac materials with & alpha; = 1. Here we analyze the effects of short-and long-range Coulomb repulsions in two-and three-dimensional FDMs. Only a strong short-range interaction causes nucleation of a correlated insulator that takes place through a quantum critical point. The universality class of the associated quantum phase transition is determined by the correlation length exponent & nu;-1 = d - & alpha; and dynamic scaling exponent z = & alpha;, set by the band curvature. On the other hand, the fractional dispersion is protected against long-range interaction due to its nonanalytic structure. Rather, a linear Dirac dispersion gets generated under coarse graining, and the associated Fermi velocity increases logarithmically in the infrared regime, thereby yielding a two-fluid system. Altogether, correlated FDMs unfold a rich landscape accommodating unconventional emergent many-body phenomena.

  • 104657. Roy, Bitan
    et al.
    Juričić, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Fermionic multicriticality near Kekule valence-bond ordering on a honeycomb lattice2019In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 99, no 24, article id 241103Article in journal (Refereed)
    Abstract [en]

    We analyze the possibility of emergent quantum multicritical points (MCPs) with enlarged chiral symmetry, when strongly interacting gapless Dirac fermions acquire a comparable propensity toward the nucleation of Kekule valence-bond solid (KVBS) and charge-density-wave (N-b = 1) or s-wave pairing (N-b = 2) or antiferromagnet (N-b = 3) in a honeycomb lattice, where N-b counts the number of bosonic order-parameter components. Besides the cubic terms present in the order-parameter description of KVBS due to the breaking of a discrete Z(3) symmetry, quantum fluctuations generate new cubic vertices near the high-symmetry MCPs. All cubic terms are strongly relevant at the bare level near three spatial dimensions, about which we perform a leading-order renormalization group analysis of coupled Gross-Neveu-Yukawa field theory. We show that due to nontrivial Yukawa interactions among gapless bosonic and fermionic degrees of freedom, all cubic terms ultimately become irrelevant at an O(2 + N-b) symmetric MCP, at leas near two spatial dimensions, where N-b = 1, 2, 3. Therefore, MCPs with an enlarged O(2 + N-b) symmetry near KVBS ordering are stable.

  • 104658. Roy, Bitan
    et al.
    Juričič, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita). Universidad Técnica Federico Santa María, Chile.
    Dislocation as a bulk probe of higher-order topological insulators2021In: Physical Review Research, E-ISSN 2643-1564, Vol. 3, no 3, article id 033107Article in journal (Refereed)
    Abstract [en]

    Topological materials occupy the central stage in the modern condensed matter physics because of their robust metallic edge or surface states protected by the topological invariant, characterizing the electronic band structure in the bulk. Higher-order topological (HOT) states extend this usual bulk-boundary correspondence, so they host the modes localized at lower-dimensional boundaries, such as corners and hinges. Here we theoretically demonstrate that dislocations, ubiquitous defects in crystalline materials, can probe higher-order topology, recently realized in various platforms. We uncover that HOT insulators respond to dislocations through symmetry protected finite-energy in-gap electronic modes, localized at the defect core, which originate from an interplay between the orientation of the HOT mass domain wall and the Burgers vector of the dislocation. As such, these modes become gapless only when the Burgers vector points toward lower-dimensional gapless boundaries. Our findings are consequential for the systematic probing of the extended bulk-boundary correspondence in a broad range of HOT crystals and photonic and phononic or mechanical metamaterials through the bulk topological lattice defects.

  • 104659. Roy, Bitan
    et al.
    Juričič, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita). Universidad Técnica Federico Santa María, Chile.
    Mixed-parity octupolar pairing and corner Majorana modes in three dimensions2021In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 104, no 18, article id L180503Article in journal (Refereed)
    Abstract [en]

    We identify time-reversal symmetry breaking mixed-parity superconducting states that feature eight Majorana corner modes in properly cleaved three-dimensional cubic crystals. Namely, when an odd-parity isotropic p-wave pairing coexists with cubic symmetry preserving even-parity octupolar d(x2-y2) + id(3z2-r2) pairing, the gapless surface Majorana modes of the former get localized at the eight corners, thus yielding an intrinsic third-order topological superconductor (TOTSC). A cousin d(xy) + id(3z2-r2) pairing also accommodating eight corner Majorana modes, by virtue of breaking the cubic symmetry, in contrast, yields an extrinsic TOTSC. We identify a doped octupolar (topological or trivial) Dirac insulator as a suitable platform to sustain such unconventional superconductors, realized from an intraunit cell pairing. Finally, we argue that the proposed TOTSC can be experimentally realizable in NaCl and other structurally similar compounds under high pressure.

  • 104660. Roy, Bitan
    et al.
    Kennett, Malcolm P.
    Yang, Kun
    Juričić, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    From Birefringent Electrons to a Marginal or Non-Fermi Liquid of Relativistic Spin-1/2 Fermions: An Emergent Superuniversality2018In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 121, no 15, article id 157602Article in journal (Refereed)
    Abstract [en]

    We present the quantum critical theory of an interacting nodal Fermi liquid of quasirelativistic pseudospin-3/2 fermions that have a noninteracting birefringent spectrum with two distinct Fermi velocities. When such quasiparticles interact with gapless bosonic degrees of freedom that mediate either the long-range Coulomb interaction or its short range component (responsible for spontaneous symmetry breaking), in the deep infrared or quantum critical regime in two dimensions, the system is, respectively, described by a marginal- or a non-Fermi liquid of relativistic spin-1/2 fermions (possessing a unique velocity), and is always a marginal Fermi liquid in three dimensions. We consider a possible generalization of these scenarios to fermions with an arbitrary half-odd-integer spin, and conjecture that critical spin-1/2 excitations represent a superuniversal description of the entire family of interacting quasirelativistic fermions.

  • 104661. Roy, Bitan
    et al.
    Slager, Robert-Jan
    Juričić, Vladimir
    Stockholm University, Nordic Institute for Theoretical Physics (Nordita).
    Global Phase Diagram of a Dirty Weyl Liquid and Emergent Superuniversality2018In: Physical Review X, E-ISSN 2160-3308, Vol. 8, no 3, article id 031076Article in journal (Refereed)
    Abstract [en]

    Pursuing complementary field-theoretic and numerical methods, we here paint the global phase diagram of a three-dimensional dirty Weyl system. The generalized Harris criterion, augmented by a perturbative renormalization-group analysis shows that weak disorder is an irrelevant perturbation at the Weyl semimetal (WSM)-insulator quantum-critical point. But, a metallic phase sets in through a quantum phase transition (QPT) at strong disorder across a multicritical point. The field-theoretic predictions for the correlation length exponent v = 2 and dynamic scaling exponent z = 5/4 at this multicritical point are in good agreement with the ones extracted numerically, yielding v = 1.98 +/- 0.10 and z = 1.26 +/- 0.05, from the scaling of the average density of states (DOS). Deep inside the WSM phase, generic disorder is also an irrelevant perturbation, while a metallic phase appears at strong disorder through a QPT. We here demonstrate that in the presence of generic but strong disorder, the WSM-metal QPT is ultimately always characterized by the exponents v = 1 and z = 3/2 (to one-loop order), originating from intranode or chiral-symmetric (e.g., regular and axial potential) disorder. We here anchor such emergent chiral super-universality through complementary renormalization-group calculations, controlled via. expansions, and numerical analysis of average DOS across WSM-metal QPT. In addition, we also discuss a subsequent QPT (at even stronger disorder) of a Weyl metal into an Anderson insulator by numerically computing the typical DOS at zero energy. The scaling behavior of various physical observables, such as residue of quasiparticle pole, dynamic conductivity, specific heat, Gruneisen ratio, inside various phases as well as across various QPTs in the global phase diagram of a dirty Weyl liquid, are discussed.

  • 104662. Roy, Monika A.
    et al.
    Cousins, Ian
    Stockholm University, Faculty of Science, Department of Environmental Science.
    Harriman, Elizabeth
    Scheringer, Martin
    Tickner, Joel A.
    Wang, Zhanyun
    Combined Application of the Essential-Use and Functional Substitution Concepts: Accelerating Safer Alternatives2022In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 56, no 14, p. 9842-9846Article in journal (Other academic)
  • 104663. Roy, Rupak
    et al.
    Kumar, Brijesh
    Maund, Justyn R.
    Schady, Patricia
    Olivares, E. Felipe
    Malesani, Daniele
    Leloudas, Giorgos
    Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC). Stockholm University, Faculty of Science, Department of Physics. Univ Copenhagen, Niels Bohr Inst, Dark Cosmol Ctr, DK-2100 Copenhagen O, Denmark.
    Nandi, Sumana
    Tanvir, Nial
    Milisavljevic, Dan
    Hjorth, Jens
    Misra, Kuntal
    Kumar, Brajesh
    Pandey, S. B.
    Sagar, Ram
    Chandola, H. C.
    SN 2007uy-metamorphosis of an aspheric Type Ib explosion2013In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 434, no 3, p. 2032-2050Article in journal (Refereed)
    Abstract [en]

    The supernovae (SNe) of Type Ibc are rare and the detailed characteristics of these explosions have been studied only for a few events. Unlike Type II SNe, the progenitors of Type Ibc have never been detected in pre-explosion images. So, to understand the nature of their progenitors and the characteristics of the explosions, investigation of proximate events is necessary. Here we present the results of multiwavelength observations of Type Ib SN 2007uy in the nearby (similar to 29.5 Mpc) galaxy NGC 2770. Analysis of the photometric observations revealed this explosion as an energetic event with peak absolute R-band magnitude -18.5 +/- 0.16, which is about 1 mag brighter than the mean value (-17.6 +/- 0.6) derived for well observed Type Ibc events. The SN is highly extinguished, E(B - V) = 0.63 +/- 0.15 mag, mainly due to foreground material present in the host galaxy. From optical light curve modelling we determine that about 0.3 M-circle dot radioactive Ni-56 is produced and roughly 4.4 M-circle dot material is ejected during this explosion with liberated energy similar to 15 x 10(51) erg, indicating the event to be an energetic one. Through optical spectroscopy, we have noticed a clear aspheric evolution of several line-forming regions, but no dependency of asymmetry is seen on the distribution of Ni-56 inside the ejecta. The SN shock interaction with the circumstellar material is clearly noticeable in radio follow-up, presenting a synchrotron self-absorption dominated light curve with a contribution of free-free absorption during the early phases. Assuming a Wolf-Rayet (WR) star, with wind velocity greater than or similar to 10(3) km s(- 1), as a progenitor, we derive a lower limit to the mass-loss rate inferred from the radio data as M 2.4 10(-5) M-circle dot yr(-1), which is consistent with the results obtained for other Type Ibc SNe bright at radio frequencies.

  • 104664.
    Roy, Rupak
    et al.
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Sollerman, Jesper
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Silverman, J. M.
    Pastorello, A.
    Fransson, Claes
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Drake, A.
    Taddia, Francesco
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Fremling, Christoffer
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Kankare, E.
    Kumar, B.
    Cappellaro, E.
    Bose, S.
    Benetti, S.
    Filippenko, A. V.
    Valenti, S.
    Nyholm, Anders
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Ergon, Mattias
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Sutaria, F.
    Kumar, B.
    Pandey, S. B.
    Nicholl, M.
    Garcia-Alvarez, D.
    Tomasella, L.
    Karamehmetoglu, Emir
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Migotto, Katia
    Stockholm University, Faculty of Science, Department of Astronomy. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    SN 2012aa: A transient between Type Ibc core-collapse and superluminous supernovae2016In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 596, article id A67Article in journal (Refereed)
    Abstract [en]

    Context. Research on supernovae (SNe) over the past decade has confirmed that there is a distinct class of events which are much more luminous (by similar to 2 mag) than canonical core-collapse SNe (CCSNe). These events with visual peak magnitudes less than or similar to-21 are called superluminous SNe (SLSNe). The mechanism that powers the light curves of SLSNe is still not well understood. The proposed scenarios are circumstellar interaction, the emergence of a magnetar after core collapse, or disruption of a massive star through pair production. Aims. There are a few intermediate events which have luminosities between these two classes. They are important for constraining the nature of the progenitors of these two different populations and their environments and powering mechanisms. Here we study one such object, SN 2012aa. Methods. We observed and analysed the evolution of the luminous Type Ic SN 2012aa. The event was discovered by the Lick Observatory Supernova Search in an anonymous galaxy (z approximate to 0.08). The optical photometric and spectroscopic follow-up observations were conducted over a time span of about 120 days. Results. With an absolute V-band peak of similar to-20 mag, the SN is an intermediate-luminosity transient between regular SNe Ibc and SLSNe. SN 2012aa also exhibits an unusual secondary bump after the maximum in its light curve. For SN 2012aa, we interpret this as a manifestation of SN-shock interaction with the circumstellar medium (CSM). If we assume a Ni-56-powered ejecta, the quasi-bolometric light curve requires roughly 1.3 M-circle dot of Ni-56 and an ejected mass of similar to 14 M-circle dot. This also implies a high kinetic energy of the explosion, similar to 5.4 x 10(51) erg. On the other hand, the unusually broad light curve along with the secondary peak indicate the possibility of interaction with CSM. The third alternative is the presence of a central engine releasing spin energy that eventually powers the light curve over a long time. The host of SN 2012aa is a star-forming Sa/Sb/Sbc galaxy. Conclusions. Although the spectral properties of SN 2012aa and its velocity evolution are comparable to those of normal SNe Ibc, its broad light curve along with a large peak luminosity distinguish it from canonical CCSNe, suggesting that the event is an intermediate-luminosity transient between CCSNe and SLSNe at least in terms of peak luminosity. In comparison to other SNe, we argue that SN 2012aa belongs to a subclass where CSM interaction plays a significant role in powering the SN, at least during the initial stages of evolution.

  • 104665.
    Roy, Sofie
    Stockholm University, Faculty of Social Sciences, Stockholm Business School.
    Navigating in the knowledge era: metaphors and stories in the construction of Skandia's navigator2003Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Within the dominant knowledge management literature, knowledge is often treated as a given, codifiable, and sharable strategic resource. Various tools have been developed to manage knowledge, and the focus of this thesis is on one such tool; the balanced scorecard. The assumption underlying the balanced scorecard is that organisational actors are to acquire ‘true knowledge’ about what is ‘really going on in the organisation’ by using it. Furthermore, the development of a shared language is supposed to enable the actors to talk about, create a shared understanding for, and deal with reality assumed to exist ‘out there’.

    Rather contrary to these assumptions, this thesis treats knowledge as a process situated in practice, where talk is the practice in focus. What is referred to as knowledge processes are seen as taking place during practice, leading to the construction of knowledge structures. These structures, in turn, give form to the processes. With such an approach, the aim of this study is to create an understanding for the role of balanced scorecards as linguistic tools within knowledge management practices, and to contribute to a conceptualisation of knowledge seen as a process.

    To fulfil this aim, an in-depth study of Skandia’s work with the Navigator, their equivalent to the balanced scorecard, has been conducted. Metaphors and stories have been interpreted as being central as they have been used to spread ideas about the Navigator and to shape the development of knowledge. Moreover, some organisational actors’ practices have been interpreted as storymaking through which actors enact and make sense of their practices. It is concluded that rather than developing shared knowledge about reality ‘out there’, or what is labelled one continent of knowledge, the actors construct several temporary knowledge isles that take various forms and characteristics depending on when and how they are used. These knowledge isles are not manageable in the sense that they can be controlled. Instead they become in-formed, i.e., they are given form through the use of balanced scorecards.

  • 104666. Roy, Souvik
    et al.
    Huang, Zhehao
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Bhunia, Asamanjoy
    Castner, Ashleigh
    Gupta, Arvind K.
    Zou, Xiaodong
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Ott, Sascha
    Electrocatalytic Hydrogen Evolution from a Cobaloxime-Based Metal-Organic Framework Thin Film2019In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 141, no 40, p. 15942-15950Article in journal (Refereed)
    Abstract [en]

    Molecular hydrogen evolution catalysts (HECs) are synthetically tunable and often exhibit high activity, but they are also hampered by stability concerns and practical limitations associated with their use in the homogeneous phase. Their incorporation as integral linker units in metal-organic frameworks (MOFs) can remedy these shortcomings. Moreover, the extended three-dimensional structure of MOFs gives rise to high catalyst loadings per geometric surface area. Herein, we report a new MOF that exclusively consists of cobaloximes, a widely studied HEC, that act as metallo-linkers between hexanuclear zirconium clusters. When grown on conducting substrates and under applied reductive potential, the cobaloxime linkers promote electron transport through the film as well as function as molecular HECs. The obtained turnover numbers are orders of magnitude higher than those of any other comparable cobaloxime system, and the molecular integrity of the cobaloxime catalysts is maintained for at least 18 h of electrocatalysis. Being one of the very few hydrogen evolving electrocatalytic MOFs based on a redox-active metallo-linker, this work explores uncharted terrain for greater catalyst pathways.

  • 104667. Roy, Souvik
    et al.
    Pascanu, Vlad
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pullen, Sonja
    González Miera, Greco
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Martín-Matute, Belén
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ott, Sascha
    Catalyst accessibility to chemical reductants in metal-organic frameworks2017In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 53, no 22, p. 3257-3260Article in journal (Refereed)
    Abstract [en]

    A molecular H-2-evolving catalyst, [Fe-2(cbdt)(CO)(6)] ([FeFe], cbdt = 3-carboxybenzene-1,2-dithiolate), has been attached covalently to an amino-functionalized MIL-101(Cr) through an amide bond. Chemical reduction experiments reveal that the MOF channels can be clogged by ion pairs that are formed between the oxidized reductant and the reduced catalyst. This effect is lessened in MIL-101-NH-[FeFe] with lower [FeFe] loadings. On longer timescales, it is shown that large proportions of the [FeFe] catalysts within the MOF engage in photochemical hydrogen production and the amount of produced hydrogen is proportional to the catalyst loading.

  • 104668. Roy, Souvik
    et al.
    Pascanu, Vlad
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pullen, Sonja
    González-Miera, Greco
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Martín-Matute, Belén
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ott, Sascha
    A MOF-Supported H2 Evolution Photocatalyst with Remarkable Stability and Improved EfficiencyArticle in journal (Refereed)
  • 104669.
    Roy, Travis
    Stockholm University, Faculty of Social Sciences, Department of Education.
    Student Perceptions & The Value of Studying Abroad: A Look at Michigan State University Undergraduate Business Students2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The multitude of existing research conducted within the field of study abroad programs generally reinforces the popular understanding that the practice not only broadens the mind, provides valuable experiences and enhances stagnating perspectives, but also contributes to a skillset that is becoming increasingly necessary for success in the globally focused world of today. Despite the evidence supporting their effectiveness, relatively few undergraduate students in the United States choose to participate in some form of study abroad program. The following analysis will examine the potential reasoning of why this is so.

    Through the administration of questionnaires and interviews along with a comprehensive review of existing research, the following pages examine the attitudes and inhibitions of undergraduate university students as they relate to studying abroad and to what extent these perceptions fall in line with the escalating importance of multicultural competence. Used as an exemplifying case of American undergraduate students, Michigan State University’s Eli Broad College of Business furnished the sample of participants used in this study.

    Largely supported through the data obtained from the conducted interviews, undergraduate students are seen to place a high value on the personal and cultural benefits acquired through study abroad participation while relegating academic focus to a somewhat tangential position. Factors such as a student’s previous international travel experience and awareness of available programs are seen to influence these perceptions to some degree. Despite the significant value placed on such programs, a large percentage of students express concern over a variety of barriers prohibiting them from pursuing enrollment. The financial commitments associated with the participation in a study abroad program were almost unanimously considered to be a serious burden on individuals. These concerns were supplemented and at times exacerbated by other factors such as a student’s availability of time, willingness to suspend important personal relationships and needed class credit.

    Covered in detail below, these findings are seen to support and corroborate much of the existing research that has been previously conducted within this field while providing additional insight by way of student testimony.

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  • 104670.
    Roy, Vilasini
    Stockholm University, Faculty of Humanities, Department of English.
    New Homes and New Names: The African Migrant Novelin the Digital Age2016Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this thesis, I attempt to explore the development of migrant literature in an era of digitalcommunication. The latest developments in communication technology have certainlydestabilized patterns of content creation and dissemination. While many use it uncritically,mostly as a means of information and keeping in contact, there are new avenues open forthose who wish to engage actively and create a space for new dialogue. And though theseonline platforms have not completely overturned hierarchies between literatures from theWest versus the global South, they have certainly altered both the content and form of workoriginating from African countries. By doing so, digital technology has boosted the creationof an African identity that moves away from victimhood by reimagining ideas of what itmeans to be and write from an African perspective where a multiplicity and hybridity ofvoices exist. I have chosen three “digital migrant novels” (Caren Irr’s term): ChimamandaNgozi Adichihe’s Americanah, NoViolet Bulawayo’s We Need New Names, and Open Cityby Teju Cole. I begin by situating these novels in a technologically sophisticated, mediaoriented space, where the geography of nations is challenged by overlapping spaces of digitalcommunication. My aim is threefold – to identify new patterns in migrant identity and to seehow they are affected by technology use; to see whether these patterns correspond to theemergence of an Afropolitan identity (and to understand what permutations this Afropolitanidentity can take on). And and finally, to analyse how digital media communication shapes amigrant’s relationship to homeland and language.

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  • 104671.
    Royan, Media
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Transnationalism Practices by the Kurdish Diaspora Elite: -The role of the Swedish Kurdish diaspora elite -2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Abstract

    In the past, the main focus of migration studies was the investigation of influences of immigrants on the host society and their integration into the country of settlement. However, transnationalism studies currently place much greater emphasis upon the other side – which is the effect of living in diaspora, in the society of origin with trans-border citizenship. The cultural, social and political interactions and connections between Sweden as a country of settlement and Kurdistan (especially Iraqi Kurdistan), create a transnational social space where the members of the Kurdish elite can play a major role in improvement of Kurdistan. From here, their adoption of a double identity makes it possible for them to permanently define and redefine their position in Swedish society while simultaneously participating in the inherent development of Kurdistan.

    The merging of the members of the Kurdish elite’s discourse in rebuilding of democracy and development with regard to reconstruction, leads to more focus on the role of diaspora and understanding the Swedish Kurdish elite’s impact on “functionalizing” and major contribution in the current state of Kurdistan. The ways of expression, increasing academic value, multicultural behavior, and the elite’s activities in civil society organization in between two or several states, their appearance in the international scene, experiences of living in both host / home societies, and multi-relations in a diasporic context continuing and re-adjusting national identities are essential indications of trans-border identity formation of Kurdish diaspora.

    After the liberation of Kurdistan (northern Iraq 2003), members of the Kurdish elite experienced transnationalism mainly through transferring their success in performing various activities for their homeland and at the same time integrating more into the host countries that received them. During this research, the researcher met and interviewed a number of members of Kurdish elites who had very interesting stories about the Kurdish diaspora, and more especially the important role they play in the transnational space that connects the Kurdish homeland to many European countries and the United States. Using a phenomenology method, the researcher classifies the elements that can characterize the practices of Kurdish diaspora elite as transnationalism. 

    Sweden is one of the main countries where the Kurdish elite diaspora gathered and are organized to contribute to the development of Kurdistan. Since the Kurdish diaspora is the largest nation that lacks a state, the Kurdish diaspora has formed a long-distance nation in host country.

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    Transnationalism Practices by the Kurdish Diaspora Elite
  • 104672.
    Roychowdhury, Krishanu
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Moessner, Roderich
    Das, Arnab
    Dynamics and correlations at a quantum phase transition beyond Kibble-Zurek2021In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 104, no 1, article id 014406Article in journal (Refereed)
    Abstract [en]

    Kibble-Zurek theory (KZ) stands out as the most robust theory of defect generation in the dynamics of phase transitions. KZ utilizes the structure of equilibrium states away from the transition point to estimate the excitations due to the transition using adiabatic and impulse approximations. Here we show, the actual nonequilibrium dynamics lead to a qualitatively different scenario from KZ, as far correlations between the defects (rather than their densities) are concerned. For a quantum Ising chain, we show, this gives rise to a Gaussian spatial decay in the domain wall (kinks) correlations, while KZ would predict an exponential fall. We propose a simple but general framework on top of KZ, based on the “quantum coarsening” dynamics of local correlators in the supposed impulse regime. We outline how our picture extends to generic interacting situations.

  • 104673.
    Royen, P.
    et al.
    Stockholm University, Faculty of Science, Department of Physics.
    Gurell, J.
    Stockholm University, Faculty of Science, Department of Physics.
    Lundin, P.
    Stockholm University, Faculty of Science, Department of Physics.
    Norlin, L-O
    Mannervik, S.
    Stockholm University, Faculty of Science, Department of Physics.
    Monitoring the weak collisional excitation of a stored ion beam reveals the radiative decay rate of extremely long-lived metastable levels2007In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 76, no 3, p. 030502-Article in journal (Refereed)
    Abstract [en]

    A fast ion beam stored in an ion storage ring will suffer from collisional interaction with the residual gas even in extreme ultrahigh vacuum. Normally these effects are negligible or easy to correct for. For measurements of extremely long radiative lifetimes of metastable levels we have found that correction for collisional effects is very important and usually limits the accuracy. We now suggest that by monitoring the process of collisional excitation of the metastable level of interest the lifetime value could be determined directly with improved accuracy. The method is applied to available data from our recent measurement of the 5d 2D5∕2 level in Ba+, yielding a value of 32.0±2.9 s, thus squeezing the error bar by 35%.

  • 104674.
    Royen, Peder
    Stockholm University.
    Laser spectroscopic investigations of some diatomic molecules1987Doctoral thesis, comprehensive summary (Other academic)
  • 104675. Royer, P.
    et al.
    Decin, L.
    Wesson, R.
    Barlow, M. J.
    Polehampton, E. T.
    Matsuura, M.
    Agundez, M.
    Blommaert, J. A. D. L.
    Cernicharo, J.
    Cohen, M.
    Daniel, F.
    Degroote, P.
    De Meester, W.
    Exter, K.
    Feuchtgruber, H.
    Gear, W. K.
    Gomez, H. L.
    Groenewegen, M. A. T.
    Hargrave, P. C.
    Huygen, R.
    Imhof, P.
    Ivison, R. J.
    Jean, C.
    Kerschbaum, F.
    Leeks, S. J.
    Lim, T.
    Lombaert, R.
    Olofsson, Göran
    Stockholm University, Faculty of Science, Department of Astronomy.
    Posch, T.
    Regibo, S.
    Savini, G.
    Sibthorpe, B.
    Swinyard, B. M.
    Vandenbussche, B.
    Waelkens, C.
    Witherick, D. K.
    Yates, J. A.
    PACS and SPIRE spectroscopy of the red supergiant VY CMa2010In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 518, p. L145-Article in journal (Refereed)
    Abstract [en]

    With a luminosity > 10(5) L-circle dot and a mass-loss rate of similar to 2 x 10(-4) M-circle dot yr(-1), the red supergiant VY CMa truly is a spectacular object. Because of its extreme evolutionary state, it could explode as supernova any time. Studying its circumstellar material, into which the supernova blast will run, provides interesting constraints on supernova explosions and on the rich chemistry taking place in such complex circumstellar envelopes. We have obtained spectroscopy of VY CMa over the full wavelength range offered by the PACS and SPIRE instruments of Herschel, i.e. 55-672 micron. The observations show the spectral fingerprints of more than 900 spectral lines, of which more than half belong to water. In total, we have identified 13 different molecules and some of their isotopologues. A first analysis shows that water is abundantly present, with an ortho-to-para ratio as low as similar to 1.3:1, and that chemical non-equilibrium processes determine the abundance fractions in the inner envelope.

  • 104676.
    Roza, Manfred
    et al.
    National Aerospace Laboratory (NLR), , Training and Simulation Systems.
    Voogd, Jeroen
    Netherlands Organisation for Applied Scientific Research (TNO), , Behavioural and Societal Sciences.
    Giannoulis, Constantinos
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    The GM-VV: It’s Relationship to the VV&A Overlay for the FEDEP2011In: 2011 Fall Simulation Interoperability Workshop, Orlando, FL, USA: SISO , 2011Conference paper (Refereed)
    Abstract [en]

    The Generic Methodology for Verification and Validation (GM-VV) is a generic methodology for VV&A to justify the acceptability of models, simulation, underlying data and results for an intended use. This methodology is currently in the processes of standardization within the SISO. The GM-VV attains its genericness from an abstractly defined reference framework approach, instead of trying to cover or merge all possible and existing VV&A methods into a single one-size-fits-all VV&A method implementation. This means that the GM-VV is neither prescriptive in nature, nor directly tied to any specific M&S application domain, standard, technology, organization or other distinctive M&S context related VV&A details. The GM-VV provides a three tier reference framework that consists of a conceptual, an implementation and a tailoring framework. The first two are aimed at facilitating communication, understanding and implementation of VV&A across and between different M&S contexts. The tailoring framework is applied to cost-efficiently develop and apply concrete VV&A method instantiations that meet the individual M&S organization, project, technology or application domain needs and constraints. This paper demonstrates how the established VV&A overlay for the FEDEP (IEEE 1516.4) is encompassed by the GM-VV and how it can be derived from its reference framework. A mapping between the VV&A Overlay terminology, definitions and concepts, and those of the GM-VV is provided. Detailed mappings of the VV&A overlay roles, processes and products onto the GM-VV implementation framework components illustrate the tailoring of GM-VV towards a VV&A method instance that fits a specific M&S technology, the FEDEP (1516.3). These mappings serve as an educational example to improve the understanding of the GM-VV purpose, usage and relationship to other VV&A standards.

  • 104677. Roza, Manfred
    et al.
    Voogd, Jeroen
    Giannoulis, Constantinos
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Towards A Generic Data Information Model for VV&A2008In: 2008 Spring Simulation and Interoperability Workshop, SISO , 2008Conference paper (Refereed)
  • 104678. Rozemeijer, J. C.
    et al.
    van der Velde, Y.
    Deltares, Utrecht, Netherlands.
    McLaren, R. G.
    van Geer, F. C.
    Broers, H. P.
    Bierkens, M. F. P.
    Integrated modeling of groundwater-surface water interactions in a tile-drained agricultural field: The importance of directly measured flow route contributions2010In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 46, p. W11537-Article in journal (Refereed)
    Abstract [en]

    Understanding the dynamics of groundwater-surface water interaction is needed to evaluate and simulate water and solute transport in catchments. However, direct measurements of the contributions of different flow routes from specific surfaces within a catchment toward the surface water are rarely available. For this study, we physically separated the tile drain discharge toward a 43.5 m ditch transect from the groundwater-plus-overland flow routes. Direct groundwater flow and ephemeral overland flow were jointly captured in three sheet pile in-stream reservoirs, while the effluent from three tile drain outlets was collected in vessels. Our flux measurements showed that, in response to a rainfall event, the tile drain contribution to the total ditch discharge decreased from 80% to 28%. We used these flow route measurements to calibrate a field-scale integrated water transport model. The HydroGeoSphere code was used because it simultaneously solves the flow regimes in the variably saturated domain, the tile drain domain, and the surface flow domain. This simultaneous solution is needed for a correct representation of the mutual interactions between groundwater flow, tile drain flow, and ditch water flow. Our model produced a flow distribution between the flow paths which deviated only 2% from the measured flow distribution. A sensitivity analysis showed that model parameters related to tile drain entrance resistance and to the resistance to water flow through the surface water system controlled the water flow route distribution but with little effect on groundwater levels. This indicates that a model calibration based on groundwater levels alone does not necessarily produce a correct representation of the flow route contributions.

  • 104679. Rozemeijer, J. C.
    et al.
    van der Velde, Y.
    Soil Physics, Ecohydrology and Groundwater management Group, Wageningen University, P.O. Box 47, NL-6700 AA Wageningen, The Netherlands.
    van Geer, F. C.
    Bierkens, M. F. P.
    Broers, H. P.
    Direct measurements of the tile drain and groundwater flow route contributions to surface water contamination: From field-scale concentration patterns in groundwater to catchment-scale surface water quality2010In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 158, no 12, p. 3571-3579Article in journal (Refereed)
    Abstract [en]

    Enhanced knowledge of water and solute pathways in catchments would improve the understanding of dynamics in water quality and would support the selection of appropriate water pollution mitigation options. For this study, we physically separated tile drain effluent and groundwater discharge from an agricultural field before it entered a 43.5-m ditch transect. Through continuous discharge measurements and weekly water quality sampling, we directly quantified the flow route contributions to surface water discharge and solute loading. Our multi-scale experimental approach allowed us to relate these measurements to field-scale NO(3) concentration patterns in shallow groundwater and to continuous NO(3) records at the catchment outlet. Our results show that the tile drains contributed 90-92% of the annual NO(3) and heavy metal loads. Considering their crucial role in water and solute transport, enhanced monitoring and modeling of tile drainage are important for adequate water quality management.

  • 104680. Rozemeijer, Joachim C.
    et al.
    Van der Velde, Ype
    Van Geer, Frans C.
    De Rooij, Gerrit H.
    Torfs, Paul J. J. F.
    Broers, Hans Peter
    Improving Load Estimates for NO(3) and P in Surface Waters by Characterizing the Concentration Response to Rainfall Events2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, p. 6305-6312Article in journal (Refereed)
    Abstract [en]

    For the evaluation of action programs to reduce surface water pollution, water authorities invest heavily in water quality monitoring. However, sampling frequencies are generally insufficient to capture the dynamical behavior of solute concentrations For this study, we used on-site equipment that performed semicontinuous (15 min interval) NO(3) and P concentration measurements from June 2007 to July 2008 We recorded the concentration responses to rainfall events with a wide range in antecedent conditions and rainfall durations and intensities. Through sequential linear multiple regression analysis, we successfully related the NO(3) and P event responses to high-frequency records of precipitation, discharge, and groundwater levels We applied the regression models to reconstruct concentration patterns between low-frequency water quality measurements. This new approach significantly improved load estimates from a 20% to a 1% bias for NO(3) and from a 63% to a 5% bias for P. These results demonstrate the value of commonly available precipitation, discharge, and groundwater level data for the interpretation of water quality measurements. Improving load estimates from low-frequency concentration data Just requires a period of high-frequency concentration measurements and a conceptual, statistical, or physical model for relating the rainfall event response of solute concentrations to quantitative hydrological changes.

  • 104681. Rozemeijer, Joachim
    et al.
    van der Velde, Ype
    Wageningen Univ, Soil Phys Ecohydrol & Groundwater Management Grp, NL-6700 AA Wageningen, Netherlands.
    de Jonge, Hubert
    van Geer, Frans
    Broers, Hans-Peter
    Bierkens, Marc
    Application and Evaluation of a New Passive Sampler for Measuring Average Solute Concentrations in a Catchment Scale Water Quality Monitoring Study2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, no 4, p. 1353-1359Article in journal (Refereed)
    Abstract [en]

    We present a field based testing, optimization, and evaluation study of the SorbiCell sampler (SC-sampler); a new passive sampling technique that measures average concentrations over longer periods of time (days to months) for various substances. We tested the SC-sampler within a catchment-scale monitoring study of NO(3) and P concentrations in surface water and the drain effluent. Based on our field experiences, we optimized the flow velocity control and the sample volume capacity of the SC-samplers. The SC-samplers were capable of reproducing the NO(3) concentration levels and the seasonal patterns that were observed with weekly conventional grab sampling and continuous water quality measurements. Furthermore, we demonstrated that average measurements produce more consistent load estimates than “snapshot” concentrations from grab sampling. Therefore, when the purpose of a monitoring program is to estimate reliable (trends in) average concentrations or loads, the SC-samplers are a cost-effective alternative for grab sampling.

  • 104682.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Aesthetics of Remanence: Analogue Video in the Age of Retrospectacle2017Conference paper (Refereed)
    Abstract [en]

    This paper proposes a new conceptual frame for the study of analogue video aesthetics in digital culture. Updating Guy Debord’s notion of a “society of the spectacle” (1994), it will argue that we have entered an age of retrospectacle whose dominant signifier is an aesthetics of “remanence”—a term that fuses the magnetic materiality of analogue video with the cultural situation in which it finds itself today.

    Today, a variety of digital media objects have rendered the “VHS style” look ubiquitous. As retro fixation fixates the image of remanence decay in digital code, it raises important questions about the tension between historical authenticity and artifice. Comparing three very different works produced through processes of analogue-digital remediation, the paper will show how the aesthetics of remanence constitutes a shared visual variable of digital culture, whose relation to the concept of authenticity remains highly heterogeneous and irreducible to simulacra.

    Mark Leckey’s video art work “Fiorucci Made Me Hardcore” (1999) is a “disarmingly sincere” (Higgins 2015) treatment of technostalgia; rapper Joey Bada$$’s music video “Fromdatomb$” (David M. Helman, 2012) manifests hip hop’s credo of keepin’ it realby adding traces of analogue grain to its  digital texture; and the ‘80s action pastiche Kung Fury (David Sandberg, 2015) playfully undermines both historical authenticity and medium specificity through its indiscriminate alloy of analogue and digital problems.

  • 104683.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Analogue Video in the Age of Retrospectacle: Aesthetics, Technology, Subculture2016In: Alphaville: Journal of Film and Screen Media, ISSN 2009-4078, no 12, p. 39-58Article in journal (Refereed)
    Abstract [en]

    This article explores the various manifestations of analogue video in digital culture. Introducing the framing concept of an aesthetics of remanence, it argues that the “society of the spectacle” (Debord) has entered an age of retrospectacle, a dominant signifier of which is the remediation and/or simulation of analogue videography. The concept of remanence connects the material conditions of magnetic tape with analogue video’s aesthetic expressions, and the cultural situation in which analogue video finds itself today. By looking at three different cases related to retro gaming, contemporary hip hop, and “old skool” rave, the article shows how the aesthetics of remanence remains highly susceptible to subcultural sensibilities—while it also functions as their shared visual variable. The short film Kung Fury (David Sandberg, 2015) is a playfully post-ironic recuperation of failed media technologies. The music video “Fromdatomb$” (David M. Helman, 2012) is a complex exploration of the idea(l) of the historical real. And the work of video art Fiorucci Made Me Hardcore (Mark Leckey, 1999) is a creative treatment of nostalgia which invites us to reconsider the medical origins of the term.

  • 104684.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies, Cinema Studies.
    Autopticon: An Archaeology of Video as Psychiatric Apparatus 1953-19702018Conference paper (Other academic)
    Abstract [en]

    In 1953, the staff at Agnews State Hospital in California discovered that the installation of TV sets had rendered their mental patients more docile (Tucker et. al.). Incidentally, the same year Houston’s jail installed North America’s reportedly first CCTV system for prison surveillance (BusinessWeek). This paper traces the parallel emergence of video surveillance and video therapy between 1953 and 1970, and the technical transformations that both underwent with the coming of videotape. It shows how the institutional overlaps between the two gave rise to a movement of “video self-confrontation” practitioners and proponents, culminating with the 1970 publication of the anthology Videotape Techniques in Psychiatric Training and Treatment (edited by Milton M. Berger). A forgotten psychiatric avant-garde which thrived on two remarkable postulates: that the invention of video is as important for psychiatry as the microscope was for biology and that it is a “gift” allowing us to see ourselves as others see us.

    Foucault’s failure to address the relation between mass media and modern surveillance inspired Thomas Mathiesen to introduce synopticism as a supplementary concept to panopticism. He argued that the panoptic principle of the few seeing the many was paralleled by mass media as an “enormously extensive system enabling the many to see and contemplate the few”. This paper argues that Mathiesen himself overlooked a third operative function – seeing oneself – conditioned by the media’s acquired capacity to record and instantly replay moving images. The paper thus suggests that the historical practice of video self-confrontation, premised on particular configurations of patient(s), therapist(s), and video devices, can be understood as an autoptic apparatus – one that draws on but reconfigures both panoptic and synoptic functions.

  • 104685.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies, Cinema Studies.
    Das Autopticon: Videotherapie und/als Überwachung2018In: Montage/AV. Zeitschrift für Theorie und Geschichte audiovisueller Kommunikation, ISSN 0942-4954, Vol. 27, no 1, p. 171-189Article in journal (Refereed)
  • 104686.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies, Cinema Studies.
    (Dis)figurations of The fourth kind: the new materialism of a video-film hybrid2014Conference paper (Refereed)
    Abstract [en]

    The aesthetic characteristics and cultural connotations of video have informed cinema ever since video’s emergence. Parallel to the development of video art, filmmakers like Jean-Luc Godard, Michael Haneke and Atom Egoyan have engaged themselves creatively with the electronic medium – often in (inter)medial constellations with film. This paper takes a closer look at one particular video-film hybrid. A medially complex, split-screen, science-fiction pseudo-documentary – with one part of the image constituting faux-found footage and the other an admitted re-enactment – The Fourth Kind (Olatunde Osunsanmi, 2009) employs the aesthetic strategy of representing an alien entity by way of its violent effect upon both human bodies and the electromagnetic image itself. With this notion of figuration qua video disturbance, made possible by the fluid pictoriality of the electromagnetic image, the border between the bodies in and the body of the image breaks down.

    Taking up on Gilles Deleuze’s claim that the task of art is to render invisible forces visible, the paper shows how video in The Fourth Kind thus functions according to a logic similar to the one developed by Deleuze in relation to Francis Bacon’s painting. Insofar as this logic manifests the dynamics of (dis)figuration, whereby a direct bond between the materiality of the medium and the corporeality of the figure(s) is generated, The Fourth Kind not only constitutes a philosophically fruitful example of a video-film constellation, but suggests a particular intermedial relation between video and painting as well. Ultimately, it manifests a New Materialist critique of representation, inasmuch as it is the medium’s increasing resistance to fulfilling its figurative function which produces its affective impact – the failure to record a resemblance of the figure(s) allowing the medium to show its true (sur)face.

  • 104687.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Electronic Labyrinths: An Archaeology of Videographic Cinema2019Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This study scans six decades of film history in search for video images, the imaginaries within which they are framed, and (taking cues from the archaeological methods of Friedrich Kittler and Michel Foucault) their technical, historical, and institutional conditions of existence. The British experimental science fiction film Anti-Clock (Jane Arden and Jack Bond, 1979) revolves around a video device with the capacity to confront subjects with their own repressed memory images. While being fictional, these “memory monitors” have real conditions of existence: the emergence of video therapy and surveillance practices, conceptions of video as a recording medium, and the video processing allowing for this imaginary medium’s cinematic treatment. Framing such films as videographic cinema, this study provides a mapping and tracking of works such as Anti-Clock. From prospective imaginaries of surveillance and control to retrospective ones concerned with memory and history, the two-part dissertation tracks an epistemic shift occurring between videographic cinema’s emergent phase conditioned by video as a medium for live transmission (1950s-1980s), and its remanent phase in which the video images and imaginaries become reconditioned by the reconception of video as a recording technology (1970s-2010s).

    Chapter 1 looks at the emergence of videographic cinema through 1960s science fiction films and political thrillers in which the electronic image came to connote imminent futures of surveillance and control. Chapter 2 studies films that responded to the perceived threats of broadcast TV by imagining more or less outrageous reality TV formats. Drawing on research published by a forgotten avant-garde of psychiatrists, Chapter 3 shows how video in the 1960s gave rise to a utopian belief in self-confrontation techniques whose progressive promises were complicated by explicit overlaps between video therapy and surveillance practices. Video self-confrontation techniques also inform Chapter 4, which tracks the emergence of the videographic psyche (based on an analogy between videographic and mental images) as it was invented/discovered by 1970s artists, therapists, and filmmakers – soon to crystallise into the conception of video as a means for confronting subjects with their own repressed memories. Chapter 5 zooms out to map a larger post-millennial media landscape in which the obsolescence of analogue video granted a nostalgic appeal to its particular noisy aesthetics, fusing the cultural connotations of a certain retro “VHS style” with the material conditions of magnetic recording. Continuing the mapping of analogue video in the digital age, Chapter 6 zooms in on a selection of recent films that excavate obsolete video formats to scrutinise historical events and the media conditions of their description. Having started as an archaeology of videographic cinema, the dissertation thus ends by considering videographic cinema itself as a form of archaeology.

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  • 104688.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Expanded epistemologies: Animation meets live action in contemporary Swedish documentary film2016In: Journal of Scandinavian Cinema, ISSN 2042-7891, E-ISSN 2042-7905, Vol. 6, no 2, p. 189-197Article in journal (Refereed)
    Abstract [en]

    This short subject studies configurations of animation and live action in contemporary Swedish documentary film. While digitization has challenged the indexical images verifying function, animation has been elevated to the level of legitimate document. The epistemological boundaries of documentary film have consequently been expanded, and now include the inner worlds of social subjects. In Gomd (Hidden) (Heilborn and Aronowitsch, 2002), animation and live action are repeatedly juxtaposed in order to visualize a refugee childs experienced Otherness. In Still Born (Sandzen, 2014), ultrasound footage is fused with digital film and animation to manifest the merging perspectives of a mourning mother and her aborted child.

  • 104689.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Injecting art into everyday life: the curious case of Hassel - the private investigators2015In: Daughters of Chaos: Practice, Discipline, A Life: 8th International Deleuze Studies Conference Stockholm 2015, 2015Conference paper (Refereed)
    Abstract [en]

    The purpose of this paper is to engage with the problem of repetition in commodity culture, or what could be defined as "the constant reproduction of the same thing" (Adorno and Horkheimer 1979). From the Frankfurt School's critique of the "culture industry" to the postmodern nihilism of Jean Baudrillard, a discourse of cultural pessimism develops according to which the commodification of the new promises that nothing changes, we enter an era of "pseudo-cyclical time" (Debord 1983) to finally pass into a post-historical hyper-real "where things are being replayed ad infinitum" (Baudrillard 2007). Deleuze is hardly blind to the problem that the cultural pessimists formulate, but his stance is radically different towards it: he advances the thesis that difference (in) itself is life's (un)founding principle, and that the constant reproduction of the same thing is a mere surface effect. The notion of repetition is radically reformulated, becoming the profound process through which difference is made, and art is granted a crucial differentiating function. Subsequently, "there is no other aesthetic problem than that of the insertion of art into everyday life. The more our daily life appears standardised, stereotyped and subject to an accelerated reproduction of objects of consumption, the more art must be injected into it" (Deleuze 2004).

    With the Wallander franchise reaching its 50th sequel and Beck about to appear in his 40th film, the "Swedish detective wonder" seems to be the realisation of the pessimists’ nightmare: Scandinavian crime fiction is a culture industry, if there ever was one. Acknowledging this (post)modern predicament, the paper will nevertheless take up on Deleuze's suggestion and investigate a curious case within this phenomenon: Måns Månssons highly idiosyncratic Hassel – The Private Investigators (2012). A roguish re-imagination of one of Swedish police fiction's most classical franchises, the film constitutes an artistic intervention into the seemingly unbreakable wave of Scandinavian crime fiction films – a covert work of conceptual art injected right into the channels of commercial distribution. Hassel is a film about replay ad infinitum, a "counter-actualisation" (Nilsson 2012) of the genre's action-driven, resolution-oriented logic. It follows a group of private investigators engaging in the endless re-enactment of historical events in order to solve the 30-year-old Palme murder. The film is packed with postmodern puns concerning the simulacral quality of their investigation and would thus seem to corroborate the pessimism of Baudrillard. The paper will nevertheless show how the aesthetic strategies taken by the filmmaker, including the choice to shoot the film on the obsolescent medium of S-VHS, push the film's mechanical repetitions to an unbearable point at which it breaks into the simultaneous expression of a seemingly insoluble problem and a potential solution to the very problem that it expresses.

  • 104690.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Playing with history: Be kind rewind and the dubious pleasure of historical revisionism2015In: Play/Perform/Participate: Conference Guide, 2015Conference paper (Refereed)
    Abstract [en]

    Be Kind Rewind (2008), Michel Gondry's post-cinematic celebration of VHS aesthetics and culture, has been hailed as a "glowing valentine to creativity in opposition to commerce" (Gonsalves 2009) with a "fairytale quality to it, a heart-warming sense of make-believe" (Kerr 2009). Taking analog video's sensitive storage quality as its starting point, the film revolves around the accidental de-magnetization of a whole video rental store, and the subsequent attempts to recreate this lost archive of film history by way of no-budget shot-on-video remakes.

    The purpose of this paper is to examine the ambiguous implications of the attitude towards (film) history that the film proposes, in which the celebration of creativity coincides with an apology for complete historical revisionism. Particular focus will be given to the original film-within-the film, a silent black and white pseudo-documentary around which the portrayed community is gathered, both as participants and as spectators, in a dialectics of playful self-delusion that constitutes the ideological core of the film.

    While structuralist theorists like Jean-Louis Comolli (1980) have criticized the deluding function of the cinematic "apparatus", a much more affirmative approach can be found in thinkers like Jacques Rancière and Gilles Deleuze. Rancière (2009) argues that documentary film, as a form of memory-making, is best defined as "myth", while Deleuze (1989) questions not only "myth" as a creative category, but "truth" itself, arguing that political documentary film must engage not in "the myth of a past people, but the story-telling of a people to come." While Be Kind Rewind seems to manifest Deleuze's destructive-creative approach to historiography (here manifested in the intermedial interplay between VHS and film), the paper will argue that it also highlights how an uncritical affirmation of "the powers of the false" (Deleuze 1989) remain haunted by the ghost of an "anything goes", a nihilist shadow latent in the affirmation of historical revisionism and the community that it potentially produces.

  • 104691.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Re-negotiating the real: documentary animation and its indexical other(s)2015In: The real and the intermedial, 2015, p. 46-47Conference paper (Refereed)
    Abstract [en]

    While the "real" in the documentary film is irreducible to the indexical quality of its image, it has also been claimed that "one crucial parameter of persuasion in documentary could not occur were it not for the veridical stamp of documentary's indexical sign-status" (Renov 1993). The purpose of this paper is to investigate how a number of animated documentaries face up to this challenge, engaging in a re-negotiation of the documentary "real" by setting up intricate intermedial relations between animation and its indexical other(s). The paper will argue that the insertion of photographic and videographic "verifiers" in films as historically disparate as The Sinking of the Lusitania (Winsor McCay, 1918) and Waltz with Bashir (Ari Folman, 2009) point towards the persistence of the indexical as a prerequisite for a film's documentary claim. Taking a closer look at two Swedish examples, Hidden (Gömd, Hanna Heilborn and David Aronowitsch, 2002) and Tussilago (Jonas Odell, 2010), the paper will nevertheless also show how intermedial imbrications of animated and non-animated images can disassociate the indexical image from its verifying function, while at the same time relocating the indexical itself from the image to the sound.

  • 104692.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Technostalgic bodies: the paradox of "old skool rave" videos2016Conference paper (Refereed)
    Abstract [en]

    The purpose of this paper is to rethink video artist Mark Leckey’s work Fiorucci Made Me Hardcore (1999) in the light of the recent phenomenon of decades-old “old skool rave” videos posted, viewed and commented on, on YouTube. Fiorucci Made Me Hardcore fuses fragments of found footage from the 1970s Northern Soul movement to the early days of Acid House parties. Manipulating the speed of the decayed VHS tapes that constitute the source material, and creating a disjunction between the jerky images and the intrinsically disjointed sound, the video effectively evokes the malfunctioning memories of a “technostalgic” body – deeply affected by the audiovisual material yet unable to reproduce the original event.

    Charlotte Higgins (2015) suggests that Fiorucci Made Me Hardcore “anticipated the YouTube generation’s easy manipulation of digital sources. It activated a painful yearning for a recent past just out of reach”. Posted on YouTube by the artist himself, Fiorucci Made Me Hardcore can now also be said to constitute a part of a virtual community whose nostalgic discourse seems to clash with the very logic of the source material itself. As Simon Reynolds (2011) points out, rave culture’s ecstatic imperative of dancing into the future contradicts the nostalgic tendency that it developed nonetheless. As such, it is a powerful example of our culture’s obsession with its immediate past. In addition to discussing the videos, this paper will address the discursive laments for a “superior past” that dominate the YouTube comments, suggesting that this “retro” culture carries very specific corporeal implications.

    Originally defined as a pathological condition, nostalgia has been reframed as a cultural geist. For Jean Baudrillard (2010), nostalgia for the real was precisely what fuelled its disappearance, while Fredric Jameson (1991) saw it as an affectless and depersonalised style. Digitisation has generated a specific “analog nostalgia” (Marks 2002) that has become an intrinsic component of popular culture. Laura U. Marks suggests that it expresses a “longing for analog physicality.” Paradoxically, nostalgia for bodily experience produced through the digital remediation of “old skool rave” videos is precisely what keeps the technostalgic viewer immobile in front of the screen. Engaging with these different definitions of nostalgia, the paper will thus suggest that Fiorucci Made Me Hardcore and the “old skool rave” videos produce technostalgic bodies that are stuck somewhere between a virtual Saint Vitus Dance and a veritable paralysis suggestive of a more general tendency of our culture and age.

  • 104693.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    The Banality of Benevolence: Archival Ambiguities in Pablo Larraín's No2017Conference paper (Other academic)
    Abstract [en]

    Pablo Larraín’s No (2012) is a semi-fictional account of the production process behind the 1988 television campaign that helped defeating Chilean dictator Augusto Pinochet. An estimated 30% of the film consists of archival footage, while the rest is shot on the obsolete analogue video format U-matic in order to match the archival materials. In her 2014 book The Archive Effect: Found Footage and the Audiovisual Experience of History, Jamie Baron suggests that the insertion of archival images into films is best understood from the point of view of their effect. Archival documents “exist as ‘archival’ only insofar as the viewer […] perceives certain documents within [a] film as coming from another, previous – and primary – context of use”. It follows that any confusion regarding these temporal relations also condition the archival documents’ historiographic function. Through videographic means, No’s archive effect is almost entirely and intentionally neutralised. Ideally, the audience loses the capacity to distinguish between the two original temporalities, so that “the archive becomes fiction and what is fiction becomes archive” (Larraín). This paper discusses the technological conditions, conceptual implications, and critical reactions to Larraín’s strategy. Drawing on Jean Baudrillard’s critique of historical film, the paper concludes that No’s playful neutralisation of the archive effect finally effects what Baudrillard calls the system’s “nihilism of neutralisation”, that is to say its “power to pour everything, including what denies it, into indifference.”

  • 104694.
    Rozenkrantz, Jonathan
    Stockholm University, Faculty of Humanities, Department of Media Studies, Cinema Studies.
    The precariousness of Jewish visibility: Surviving antisemitism in Swedish cinema2022In: Journal of Scandinavian Cinema, ISSN 2042-7891, E-ISSN 2042-7905, Vol. 12, no 1, p. 87-104Article in journal (Refereed)
    Abstract [en]

    The article examines Jewish 'self-images' in Swedish post-war film. Before World War II, antisemitic caricatures were prevalent in Swedish film and visual culture. Following the Holocaust, Jews as such were virtually erased from Swedish screens. Written by and starring Marie-Louise Ekman, Hallo Baby (Bergenstrahle 1976) was a rare exception, the first Swedish post-war film to explore Swedish-Jewish identity. The 2002 comedy Livet i 8 bitar (Bit by Bit) (Metzger) remains the last of only a handfid of films to fit said description. Significantly, both films draw heavily on established antisemitic tropes in their figurations of 'Jewishness'. Through historically contextualized readings of the two films, including their reception, the article thus shows how the tradition of antisemitic caricature that prevailed until World War II has continued to condition Jewish self-representation in the post-war era.

  • 104695.
    Rozenska, Agnieszka
    Stockholm University, Faculty of Humanities, Department of Baltic Languages, Finnish and German. Stockholm University.
    Der Slogan als zentrale Profilierungsaussage: Eine Analyse am Beispiel der Landtagswahl 2008 in Bayern2010Independent thesis Advanced level (degree of Master (One Year)), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Abstract

     

    The aim of the thesis is a political-linguistic analysis of slogans used during the 2008 election campaign to the Landtag of Bayern. The purpose of this analysis is to establish whether political slogans represent each party’s profile and in what way. What do the potential voters learn about the parties from their slogans? How do the slogans differ among the parties? What issues are raised in them? How are they used in a political battle?

    In the theoretical part of the thesis, the word slogan is defined and characterized from a linguistic point of view. The function of political slogans is presented, as well as the role of slogans in political communication. In addition, the first part introduces the criteria of political slogan analysis compiled by Monika Toman-Banke and explains the role and procedure of the Landtag elections 2008 in Bayern, Germany. The empirical part is devoted to the analysis of political parties, such as: die Christlich-Soziale Union (CSU), die Freie Demokratische Partei (FDP), die Grünen, die Sozialdemokratische Partei Deutschlands (SPD), die Freien Wähler, die Republikaner und die Linke.

    The following thesis proves that political slogans, more or less direct, convey a lot of information about the profile of a given political party. Moreover, it is easy to distinguish what issues are important to which party. The topics of the slogans in the 2008 Landtag elections did not differ much from the previous election. Most of the parties concentrated on weakening the CSU’s power and the willingness to revive the political scene in Bayern, which meant criticizing the CSU and the political situation in Bayern.

     

     

     

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  • 104696.
    Rozenska, Agnieszka
    Stockholm University, Faculty of Humanities, Department of Journalism, Media and Communication (JMK).
    "Outsider" - moder: en undersökning av identitetskonstruktioner i TV-serie "United States of Tara"2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Abstract

    Syftet med denna uppsats är att undersöka hur bilden av ”moderskapet” gestaltas i den amerikanska TV-serien ”United States of Tara”. De frågor som ligger till grund för undersökningen är: hur skapas och definieras identiteten av modern i serien ”United States of Tara”? Hur konstrueras relationen mellan modern och de andra familjemedlemmarna i serien? Hur förändras framställningen av den kvinnliga huvudpersonen Tara från det första till det sista avsnittet?

    Analysen utgår från en metod för analys av TV-program som presenteras i boken ”How to Study Television” (1995) av Keith Selby & Ron Cowdery, med fokus på begreppen narrativ och konstruktion.

    Materialet består av första säsongens första avsnitt och sista säsongens sista avsnitt av serien ”United States of Tara”.

    De teoretiska utgångspunkterna som ligger till grund för undersökningen är en teoriblandning av begrepp som: representation, performativitet, identitet, identitetsordningar samt Rosalind Gills teorier kring den postfeministiska kvinnan.

    Resultatet visar på att i serien ”United States of Tara” presenteras en ovanlig bild av modern, en outsider-moder som, i enlighet med den postfeministiska synen på kvinnan, genomgår en tydlig förändring under seriens gång från en svag och förvirrad kvinna till en självsäker person.

     

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  • 104697.
    Rozental, Alexander
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Clinical psychology.
    Measuring negative effects / methodological challenges2018Conference paper (Other academic)
    Abstract [en]

    Although undermined for decades, the field of negative effects in psychotherapy has become a niche of interest in the last years. This has led to a growing body of evidence in a vast array of domains, including a deeper theoretical understanding, more accurate methodological developments and accordingly more empirical studies examining this topic. As a result of this proliferation, a diversity of conceptualizations and approaches have emerged, which are necessary to be articulated in order to gain consistency for future research projects as well as for a better application of the obtained results in the clinical practice. The current structured discussion aims to present an update of the current state and the future challenges in the study of negative effects. Hence, some of the diverse research lines that arose will be outlined, including the methodological challenges, the study of negative effects within PRN infrastructures, the role of routine outcome monitoring in identifying deterioration, the alliance ruptures, the study of negative effects in technology mediated treatments and the therapist’ perspectives. By targeting these topics, the most pending issues that should be addressed will be discussed, aiming to shed light on the unanswered questions and fostering an integrated course of action for the next years with the researchers interested in the topic.

  • 104698.
    Rozental, Alexander
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Clinical psychology.
    Negative effects of Internet-based cognitive behavior therapy: Monitoring and reporting deterioration and adverse and unwanted events2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Internet-based cognitive behavior therapy (ICBT) has the potential of providing many patients with an effective form of psychological treatment. However, despite helping to improve mental health and well-being, far from everyone seem to benefit. In some cases, negative effects may also emerge. The overall aim of the present thesis was to establish the occurrence and characteristics of such incidents in ICBT using a combination of quantitative and qualitative methods. Study I determined deterioration, non-response, and adverse and unwanted events in a sample of 133 patients undergoing ICBT for social anxiety disorder. The results indicated that up to 6.8% fared worse during the treatment period, depending on the self-report measure and time point, as determined using the Reliable Change Index (RCI), while the non-response rate was between 29.3 to 86.5% at post treatment assessment, and 12.9% experienced other negative effects. Study II investigated the responses to open-ended questions on adverse and unwanted events among 556 patients in four separate clinical trials of ICBT; social anxiety disorder, panic disorder, major depressive disorder, and procrastination. In total, 9.3% reported negative effects, with a qualitative content analysis revealing two categories and four subcategories; patient-related, i.e., gaining insight and experiencing new symptoms, and treatment-related, i.e., difficulties applying the treatment interventions and problems related to the treatment format. Study III explored the number of patients achieving reliable deterioration, as determined using the RCI on the individual raw scores of 2866 patients from 29 clinical trials of ICBT. The results showed that the deterioration rate was higher among patients in a control condition, 17.4%, in comparison to treatment, 5.8%. Predictors were related to decreased odds of deterioration for patients receiving treatment; clinical severity at pre treatment assessment, being in a relationship, having a university degree, and being older. As for the control condition, only clinical severity at pre treatment assessment was associated with decreased odds of deterioration. Study IV examined a newly developed self-report measure for monitoring and reporting adverse and unwanted events, the Negative Effects Questionnaire. The results suggested a six-factor solution with 32 items; symptoms, quality, dependency, stigma, hopelessness, and failure. One-third of the patients reported experiencing unpleasant memories, stress, and anxiety, with novel symptoms and a lack of quality in the treatment and therapeutic relationship having the greatest negative impact. The general finding of the present thesis is that negative effects do occur in ICBT and that they are characterized by deterioration, non-response, and adverse and unwanted events, similar to psychological treatments delivered face-to-face. Researchers and clinicians in ICBT are recommended to monitor and report negative effects to prevent a negative treatment trend and further the understanding of what might contribute to their incidents. Future research should investigate the relationship between negative effects and treatment outcome, especially at follow-up, to examine if they are transient or enduring. Also, interviews could be conducted with those achieving reliable deterioration to explore if and how it is experienced by the patients and to see if it is attributed to the treatment interventions or other circumstances.

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  • 104699.
    Rozental, Alexander
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Clinical psychology.
    Negative effects of psychological treatments: An exploratory factor analysis of the Negative Effects Questionnaire for monitoring and reporting adverse and unwanted events2017Conference paper (Other academic)
    Abstract [en]

    Research conducted during the last decades has provided increasing evidence for the use of psychological treatments for a number of psychiatric disorders and somatic complaints. However, by focusing only on the positive outcomes, less attention has been given to the potential of negative effects. Despite indications of deterioration and other adverse and unwanted events during treatment, little is known about their occurrence and characteristics. Hence, in order to facilitate research of negative effects, a new instrument for monitoring and reporting their incidence and impact was developed using a consensus among researchers, self-reports by patients, and a literature review: the Negative Effects Questionnaire. Participants were recruited via a smartphone-delivered self-help treatment for social anxiety disorder and through the media (N = 653). An exploratory factor analysis was performed, resulting in a six-factor solution with 32 items, accounting for 57.64% of the variance. The derived factors were: symptoms, quality, dependency, stigma, hopelessness, and failure. Items related to unpleasant memories, stress, and anxiety were experienced by more than one-third of the participants. Further, increased or novel symptoms, as well as lack of quality in the treatment and therapeutic relationship rendered the highest selfreported negative impact. In addition, the findings were discussed in relation to prior research and other similar instruments of adverse and unwanted events, giving credence to the items that are included. The instrument is presently available in eleven different languages and can be freely downloaded and used from www.neqscale.com.

  • 104700.
    Rozental, Alexander
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Clinical psychology.
    Negative effects of psychotherapy: Monitoring and reporting deterioration and adverse and unwanted events2017Conference paper (Other academic)
    Abstract [sv]

    Internetbaserad kognitiv beteendeterapi (IKBT) har goda förutsättningar att hjälpa människor övervinna psykisk ohälsa och förbättra sitt välmående. Trots detta är det långtifrån alla patienter som erfar en förbättring, vissa kan till och med försämras eller uppleva andra typer av negativa effekter. Aktuell presentation summerar resultatet från fyra studier inom ramen för en doktorsavhandling i psykologi som har undersökt förekomst och kännetecken av negativa effekter i IKBT. Kvantitativa och kvalitativa ansatser har använts för att utforska fenomenet bland cirka 3000 patienter. Sammanfattningsvis försämras 5,8 % av alla patienter som får IKBT, jämfört med 17,4 % i väntelista, där bland annat högre ålder, högre utbildningsnivå och att vara i ett förhållande minskar oddsen för försämring i IKBT. På öppna frågor rapporterar även 9,3 % av alla patienter nya symptom och problem att fullfölja behandlingsprogrammen som negativt. Ett nytt självskattningsformulär utvecklades för att lättare mäta dessa typer av negativa effekter, the Negative Effects Questionnaire, bestående av 32 items där faktorerna symptom och bristande kvalitet på behandlingen förklarade den största delen av variansen. Implikationerna av fynden kommer att diskuteras, liksom vikten av fortsatt forskning för att minska risken för negativa effekter inom IKBT samt kognitiv beteendeterapi.

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