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  • 1. A. Madsen, Kevin
    et al.
    J. Bergholtz, Emil
    Stockholm University, Faculty of Science, Department of Physics.
    Brouwer, Piet W.
    Josephson effect in a Weyl SNS junction2017In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 95, no 6, article id 064511Article in journal (Refereed)
    Abstract [en]

    We calculate the Josephson current density j (phi) for a Weyl superconductor-normal-metal-superconductor junction for which the outer terminals are superconducting Weylmetals and the normal layer is a Weyl (semi) metal. We describe the Weyl (semi) metal using a simple model with two Weyl points. The model has broken time-reversal symmetry, but inversion symmetry is present. We calculate the Josephson current for both zero and finite temperature for the two pairing mechanisms inside the superconductors that have been proposed in the literature, zero-momentum BCS-like pairing and finite-momentum FFLO-like pairing, and assuming the short-junction limit. For both pairing types we find that the current is proportional to the normal-state junction conductivity, with a proportionality coefficient that shows quantitative differences between the two pairing mechanisms. The current for the BCS-like pairing is found to be independent of the chemical potential, whereas the current for the FFLO-like pairing is not.

  • 2.
    A. Manneh, Ilana
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Supporting Learning and Teaching of Chemistry in the Undergraduate Classroom2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    There is agreement in research about the need to find better ways of teaching chemistry to enhance students’ understanding. This thesis aims to contribute to the understanding of how we better support teaching and learning of undergraduate chemistry to make it meaningful and intelligible for students from the outset. The thesis is concerned with examining the interactions between student, specific content and teacher in the undergraduate chemistry classroom; that is, the processes making up the three relations of the didactic triangle. The data consists of observations of students and tutors during problem-solving activities in an introductory chemistry course and interviews with graduate students.

    Systematic analyses of the different interactions between the student, the chemistry content, and the tutor are made using the analytical tool of practical epistemology analysis. The main findings of the thesis include detailed insights into how undergraduate chemistry students deal with newly encountered content together with didactic models and concrete suggestions for improved teaching and for supporting continuity and progression in the undergraduate chemistry classroom. Specifically, I show how students deal with the chemistry content through a complex interaction of knowledge, experiences, and purposes on different levels invoked by both students and tutors as they interact with each other. Whether these interactions have a positive or negative effect on students’ learning depends on the nature of knowledge, experiences and purposes that were invoked. Moreover, the tutor sometimes invoked other purposes than the ones related to the task at hand for connecting the activity to the subject matter in general. These purposes were not always made continuous with the activity which resulting in confusion among students. The results from these analyses were used for producing hypotheses and models that could support continuity and progression during the activity. The suggested models aim to make the content more manageable and meaningful to students, enabling connections to other experiences and purposes, and helping teachers and tutors to analyze and reflect on their teaching. Moreover, a purpose- and activity-based progression is suggested that gives attention to purposes in chemistry education other than providing explanations of chemical phenomena. The aim of this ‘progression in action’ is to engage students in activities were they can see the meaning of chemical concepts and ideas through their use to accomplish different chemical tasks. A general conclusion is that detailed knowledge about the processes of teaching and learning is important for providing adequate support to both undergraduate students and university teachers in the chemistry classroom.

  • 3.
    A. Manneh, Ilana
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Hamza, Karim M.
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Rundgren, Carl-Johan
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Progression in action for developing chemical knowledgeManuscript (preprint) (Other academic)
    Abstract [en]

    In this paper, we discuss the well-known teaching challenge of how to provide undergraduate students with basic chemistry knowledge without making them experience these basics as meaningless and unintelligible. First, we situate the challenge in a classic dilemma: should we teach the necessary basic facts before the chemical explanations or should the explanations be taught before or in parallel to these facts? Here we draw on examples from interviews with graduate students reflecting on their experiences regarding their studies at the undergraduate level. Second, we suggest a way out of the dilemma, through a shift in perspective from the typical progression of facts and explanations towards a purpose and activity-based progression. We conclude with a discussion of implications of such a shift for university chemistry education together with suggestions for future research.

  • 4.
    A. Manneh, Ilana
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Hamza, Karim
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Rundgren, Carl-Johan
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    The role of anthropomorphisms in students’ reasoning about chemical structure and bonding2018In: Asia-Pacific Forum on Science Learning and Teaching, ISSN 1609-4913, E-ISSN 1609-4913, Vol. 19, no 2, article id 4Article in journal (Refereed)
    Abstract [en]

    Anthropomorphisms are widespread at all levels of the educational system even among science experts. This has led to a shift in how anthropomorphisms are viewed in science education, from a discussion of whether they should be allowed or avoided towards an interest in their role in supporting students’ understanding of science. In this study we examine the role of anthropomorphisms in supporting students’ understanding of chemistry. We analyze examples from undergraduate students’ discussions during problem-solving classes through the use of practical epistemology analysis (PEA). Findings suggest that students invoked anthropomorphisms alongside technical relations which together produced more or less chemically appropriate explanations. Also, anthropomorphisms constitute potentially productive points of departure for rendering students’ explanations more chemically appropriate. The implications of this study refer to the need to deal with anthropomorphisms explicitly and repeatedly as well as to encourage explicit connections between different parts of the explanation - teleological as well as causal.

  • 5.
    A. Manneh, Ilana
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Rundgren, Carl-Johan
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Hamza, Karim M.
    Stockholm University, Faculty of Science, Department of Mathematics and Science Education.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Tutor-student interaction in undergraduate chemistry: a case of learning to make relevant distinctions of molecular structures for determining oxidation states of atoms2018In: International Journal of Science Education, ISSN 0950-0693, E-ISSN 1464-5289, Vol. 40, no 16, p. 2023-2043Article in journal (Refereed)
    Abstract [en]

    In this study, we explore the issues and challenges involved in supporting students’ learning to discern relevant and critical aspects of determining oxidation states of atoms in complex molecules. We present a detailed case of an interaction between three students and a tutor during a problem-solving class, using the analytical tool of practical epistemology analysis (PEA). The results show that the ability to make relevant distinctions between the different parts of a molecule for solving the problem, even with the guidance of the tutor, seemed to be challenging for students. These shifts were connected to both purposes that were specific for solving the problem at hand, and additional purposes for general learning of the subject matter, in this case how to assign oxidation states in molecules. The students sometimes could not follow the additional purposes introduced by the tutor, which made the related distinctions more confusing. Our results indicate that in order to provide adequate support and guidance for students the tutor needs to consider how to sequence, move between, and productively connect the different purposes introduced in a tutor-student interaction. One way of doing that is by first pursuing the purposes for solving the problem and then successively introduce additional, more general purposes for developing students’ learning of the subject matter studied. Further recommendations drawn from this study are discussed as well.

  • 6. A. Viggiano, A
    et al.
    M. Midey and A. Ehlerding, A
    Kinetics of the reactions of ONOO- with small molecules2006In: International journal of mass spectrometry, Vol. 255, p. 65-Article in journal (Refereed)
  • 7.
    A. Zheltukhin, A
    Stockholm University, Faculty of Science, Department of Physics.
    Unification of twistors and Ramond vectors2007In: Physics letters B, Vol. 658, p. 82-Article in journal (Refereed)
  • 8. Aaberge, Rolf
    et al.
    Bourguignon, François
    Brandolini, Andrea
    Ferreira, Francisco H. G.
    Gornick, Janet G.
    Hills, John
    Jäntti, Markus
    Stockholm University, Faculty of Social Sciences, The Swedish Institute for Social Research (SOFI).
    Jenkins, Stephen P.
    Marlier, Eric
    Micklewright, John
    Nolan, Brian
    Piketty, Thomas
    Radermacher, Walter J.
    Smeeding, Timothy M.
    Stern, Nicholas H.
    Stiglitz, Joseph
    Sutherland, Holly
    Tony Atkinson and his Legacy2017In: The Review of Income and Wealth, ISSN 0034-6586, E-ISSN 1475-4991, Vol. 63, no 3, p. 411-444Article in journal (Refereed)
    Abstract [en]

    Tony Atkinson is universally celebrated for his outstanding contributions to the measurement and analysis of inequality, but he never saw the study of inequality as a separate branch of economics. He was an economist in the classical sense, rejecting any sub-field labelling of his interests and expertise, and he made contributions right across economics. His death on 1 January 2017 deprived the world of both an intellectual giant and a deeply committed public servant in the broadest sense of the term. This collective tribute highlights the range, depth and importance of Tony's enormous legacy, the product of almost fifty years’ work.

  • 9. Aaboud, M.
    et al.
    Backman, Filip
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Bertoli, Gabriele
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Bohm, Christian
    Stockholm University, Faculty of Science, Department of Physics.
    Carney, Rebecca M. D.
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Clément, Christophe
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Hellman, Sten
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Jon-And, Kerstin
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Kastanas, Alexandros
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Milstead, David A.
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Moa, Torbjörn
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Pasuwan, Patrawan
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Shaikh, Nabila W.
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Silverstein, Samuel B.
    Stockholm University, Faculty of Science, Department of Physics.
    Sjölin, Jörgen
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Strandberg, Sara
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Ughetto, Michaël
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Valdes Santurio, Eduardo
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Wallängen, Veronica
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Zwalinski, L.
    Modeling Radiation Damage Effects for Pixel Sensors in the ATLAS DetectorManuscript (preprint) (Other academic)
    Abstract [en]

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS experiment at the LHC. Given their close proximity to the interaction point, these detectors will be exposed to an unprecedented amount of radiation over their lifetime. The current pixel detector will receive damage from non-ionizing radiation in excess of 1015 1 MeV neq /cm2, while the pixel detector designed for the high-luminosity LHC must cope with an order of magnitude larger fluence. This paper presents a digitization model incorporating effects of radiation damage to the pixel sensors. The model is described in detail and predictions for the charge collection efficiency and Lorentz angle are compared with collision data collected between 2015 and 2017 (≤ 1015  1 MeV neq /cm2).

  • 10. Aad, G.
    et al.
    Abbott, B.
    Abdallah, J.
    Gellerstedt, Karl
    Stockholm University, Faculty of Science, Department of Physics.
    Measurement of the top quark pair production cross section with ATLAS in pp collisions at √s = 7 TeV in dilepton final states2011Report (Other academic)
    Abstract [en]

    A measurement is presented of the production cross section of top quark pairs (σ_{\ttbar{}}) in proton-proton (pp) collisions at √s = 7 TeV recorded with the ATLAS detector at the CERN Large Hadron Collider. Using a data sample of 35 pb−1, candidate events are selected in the dilepton topology with large missing transverse energy, \met{}, and at least two jets.

    A baseline analysis employing kinematic properties of the candidate events to separate the signal from background and using data-driven techniques to determine the most important backgrounds, results in a measurement ofσ_{\ttbar{}} = 173 ± 22(stat.)+18 −16(syst.)+8 −7(lum.) pb,

    where the three uncertainties are from statistics, systematics and integrated luminosity, respectively.

    We also perform a cross section measurement requiring at least one b-tagged jet and a looser kinematic selection that increases the signal-to-background ratio, yielding

    σ_{\ttbar{}} = 171 ± 22(stat.)+21 -16(syst.)+7 −6(lum.) pb.

    Additional studies are performed to corroborate these measurements; a technique that normalizes the \ttbar{} signal yield to the measured rate of Z decays, a two-dimensional template shape fit using the \met{} vs the number of jets to simultaneously measure the production cross sections of \ttbar{}, WW and Z → ττ final states, and a simultaneous measurement of σ_{\ttbar{}} and the b-tagging efficiency using the distribution of the number of tagged jets in each event.

    All the measurements are in good agreement with each other and the Standard Model prediction.

  • 11. Aad, G.
    et al.
    Åsman, Barbro
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Bohm, Christian
    Stockholm University, Faculty of Science, Department of Physics.
    Clément, Christophe
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Eriksson, Daniel
    Stockholm University, Faculty of Science, Department of Physics.
    Gellerstedt, Karl
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Hellman, Sten
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Hidvégi, Attila
    Stockholm University, Faculty of Science, Department of Physics.
    Holmgren, Sven-Olof
    Stockholm University, Faculty of Science, Department of Physics.
    Johansen, Marianne
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Johansson, K. Erik
    Stockholm University, Faculty of Science, Department of Physics.
    Jon-And, Kerstin
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Lesser, Jonas
    Stockholm University, Faculty of Science, Department of Physics.
    Milstead, David A.
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Moa, Torbjörn
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Nordkvist, Björn
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Ohm, Christian C.
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Ramstedt, Magnus
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Selldén, Björn
    Stockholm University, Faculty of Science, Department of Physics.
    Silverstein, Samuel B.
    Stockholm University, Faculty of Science, Department of Physics.
    Sjölin, Jörgen
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Tylmad, Maja
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Yang, Zhaoyu
    Stockholm University, Faculty of Science, Department of Physics. Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
    Zutshi, V.
    Search for New Particles in Two-Jet Final States in 7 TeV Proton-Proton Collisions with the ATLAS Detector at the LHC2010In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 105, no 16, p. 161801-Article in journal (Refereed)
    Abstract [en]

    A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the LHC and correspond to an integrated luminosity of 315 nb(-1) collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section and signal acceptance for excited-quark (q*) production as a function of q* mass. These exclude at the 95% C. L. the q* mass interval 0: 30< m(q)*< 1:26 TeV, extending the reach of previous experiments.

  • 12. Aafjes-van Doorn, Katie
    et al.
    Lilliengren, Peter
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Clinical psychology.
    Cooper, Angela
    McDonald, James
    Falkenström, Fredrik
    Patients’ Affective Processes Within Initial Experiential Dynamic Therapy Sessions2017In: Psychotherapy, ISSN 0033-3204, E-ISSN 1939-1536, Vol. 54, no 2, p. 175-183Article in journal (Refereed)
    Abstract [en]

    Research has indicated that patients’ in-session experience of previously avoided affects may be important for effective psychotherapy. The aim of this study was to investigate patients’ in-session levels of affect experiencing in relation to their corresponding levels of insight, motivation, and inhibitory affects in initial Experiential Dynamic Therapy (EDT) sessions. Four hundred sixty-six 10-min video segments from 31 initial sessions were rated using the Achievement of Therapeutic Objectives Scale. A series of multilevel growth models, controlling for between-therapist variability, were estimated to predict patients’ adaptive affect experiencing (Activating Affects) across session segments. In line with our expectations, higher within-person levels of Insight and Motivation related to higher levels of Activating Affects per segment. Contrary to expectations, however, lower levels of Inhibition were not associated with higher levels of Activating Affects. Further, using a time-lagged model, we did not find that the levels of Insight, Motivation, or Inhibition during one session segment predicted Activating Affects in the next, possibly indicating that 10-min segments may be suboptimal for testing temporal relationships in affective processes. Our results suggest that, to intensify patients’ immediate affect experiencing in initial EDT sessions, therapists should focus on increasing insight into defensive patterns and, in particular, motivation to give them up. Future research should examine the impact of specific inhibitory affects more closely, as well as between-therapist variability in patients’ in-session adaptive affect experiencing.

  • 13.
    Aagaard, Louise
    Stockholm University, Faculty of Law, Department of Law.
    Underhållsbidrag till make efter äktenskapsskillnad: en probleminventering2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 14.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Berger, David
    Stockholm University, Faculty of Science, Department of Zoology. Uppsala University, Sweden.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    The evolution of alternative developmental pathways: footprints of selection on life-history traits in a butterfly2012In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 25, no 7, p. 1377-1388Article in journal (Refereed)
    Abstract [en]

    Developmental pathways may evolve to optimize alternative phenotypes across environments. However, the maintenance of such adaptive plasticity under relaxed selection has received little study. We compare the expression of life-history traits across two developmental pathways in two populations of the butterfly Pararge aegeria where both populations express a diapause pathway but one never expresses direct development in nature. In the population with ongoing selection on both pathways, the difference between pathways in development time and growth rate was larger, whereas the difference in body size was smaller compared with the population experiencing relaxed selection on one pathway. This indicates that relaxed selection on the direct pathway has allowed life-history traits to drift towards values associated with lower fitness when following this pathway. Relaxed selection on direct development was also associated with a higher degree of genetic variation for protandry expressed as within-family sexual dimorphism in growth rate. Genetic correlations for larval growth rate across sexes and pathways were generally positive, with the notable exception of correlation estimates that involved directly developing males of the population that experienced relaxed selection on this pathway. We conclude that relaxed selection on one developmental pathway appears to have partly disrupted the developmental regulation of life-history trait expression. This in turn suggests that ongoing selection may be responsible for maintaining adaptive developmental regulation along alternative developmental pathways in these populations.

  • 15.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    Diapause induction and relaxed selection on alternative developmental pathways in a butterfly2015In: Journal of Animal Ecology, ISSN 0021-8790, E-ISSN 1365-2656, Vol. 84, no 2, p. 464-472Article in journal (Refereed)
    Abstract [en]

    Seasonal phenotypic plasticity entails differential trait expression depending on the time of season. The facultative induction of winter diapause in temperate insects is a developmental switch mechanism often leading to differential expression in life-history traits. However, when there is a latitudinal shift from a bivoltine to univoltine life cycle, selection for pathway-specific expression is disrupted, which may allow drift towards less optimal trait values within the non-selected pathway. We use field- and experimental data from five Swedish populations of Pararge aegeria to investigate latitudinal variation in voltinism, local adaptation in the diapause switch and footprints of selection on pathway-specific regulation of life-history traits and sexual dimorphism in larval development. Field data clearly illustrated how natural populations gradually shift from bivoltinism to univoltinism as latitude increases. This was supported experimentally as the decrease in direct development at higher latitudes was accompanied by increasing critical daylengths, suggesting local adaptation in the diapause switch. The differential expression among developmental pathways in development time and growth rate was significantly less pronounced in univoltine populations. Univoltine populations showed no significant signs of protandry during larval development, suggesting that erosion of the direct development pathway under relaxed selection has led to the loss of its sex-specific modifications.

  • 16.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    Latitudinal phenological adaptation: diapause induction and differentiation between alternative developmental pathways in a butterflyManuscript (preprint) (Other academic)
    Abstract [en]

    1. Seasonal phenotypic plasticity entails differential trait expression depending on the time of season. The facultative induction of winter diapause in temperate insects is a developmental switch mechanism often leading to differential expression in life history traits. However, when there is a latitudinal shift from a bivoltine to univoltine life cycle, selection for pathway-specific expression is disrupted, which may allow drift towards less optimal trait values within the non-selected pathway.

    2. We use field- and experimental data from five Swedish populations of Pararge aegeria to investigate latitudinal variation in voltinism, local adaptation in the diapause switch, and footprints of selection on pathway-specific regulation of life history traits and sexual dimorphism in larval development.

    3. Field data clearly illustrated how natural populations gradually shift from bivoltinism to univoltinism as latitude increases. This was supported experimentally as the decrease in direct development at higher latitudes was accompanied by increasing critical daylengths, suggesting local adaptation in the diapause switch.

    4. The differential expression among developmental pathways in development time and growth rate was significantly less pronounced in univoltine populations. Univoltine populations showed no significant signs of protandry during larval development, suggesting that erosion of the direct development pathway under relaxed selection has led to the loss of its sex-specific modifications.

  • 17.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Gotthard, Karl
    The development and expression of seasonal polyphenism in life-history traits in the butterfly Pararge aegeriaManuscript (preprint) (Other academic)
  • 18.
    Aalberg Haugen, Inger Marie
    Stockholm University, Faculty of Science, Department of Zoology.
    The diapause switch: Evolution of alternative developmental pathways in a butterfly2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Diapause decision is a classic example of a threshold switch mechanism with cascading effects on morphology, behaviour and life-history traits. This thesis addresses the downstream effects of the insect diapause switch, with the main focus on pathway-specific regulation of life-history traits, using the speckled wood butterfly (Pararge aegeria) as a study species. The ultimate pathway decision is made towards the end of larval development and allows the larvae to take into account up-to-date information from the environment about future conditions (Paper I, IV). However, already from an early point in development the larvae are sensitive to environmental cues and continuously adjust their growth trajectory in accordance to current information about the environmental conditions to be expected in future (Paper IV). An asymmetry in the ability to change from one developmental pathway to another at a late point in larval development suggests that the diapause and the direct pathway require different physiological preparations (Paper IV). Pathway-specific regulation of traits downstream of the diapause switch is maintained by ongoing selection. When the direct pathway is not regularly expressed, as with a shift from bivoltinism to univoltinism, relaxed selection on the unexpressed pathway leads to genetic drift and loss of protandry (Paper II, III). Natural populations display local adaptations in the diapause switch with an increase in critical daylengths as there is a gradual shift from bivoltinism to univoltinism (Paper III). This thesis highlights two aspects of the diapause decision, the determination of how and when this decision is made as well as the way the resulting pathways are moulded by selection in order to produce adaptive seasonal polyphenism in life-history traits.

  • 19. Aalbers, J.
    et al.
    Agostini, F.
    Alfonsi, M.
    Amaro, F. D.
    Amsler, C.
    Aprile, E.
    Arazi, L.
    Arneodo, F.
    Barrow, P.
    Baudis, L.
    Benabderrahmane, M. L.
    Berger, T.
    Beskers, B.
    Breskin, A.
    Breur, P. A.
    Brown, A.
    Brown, E.
    Bruenner, S.
    Bruno, G.
    Budnik, R.
    Butikofer, L.
    Calvén, Jakob
    Stockholm University, Faculty of Science, Department of Physics.
    Cardoso, J. M. R.
    Cichon, D.
    Coderre, D.
    Colijn, A. P.
    Conrad, Jan
    Stockholm University, Faculty of Science, Department of Physics.
    Cussonneau, J. P.
    Decowski, M. P.
    Diglio, S.
    Drexlin, G.
    Duchovni, E.
    Erdal, E.
    Eurin, G.
    Ferella, Alfredo
    Stockholm University, Faculty of Science, Department of Physics.
    Fieguth, A.
    Fulgione, W.
    Rosso, A. Gallo
    Di Gangi, P.
    Di Giovanni, A.
    Galloway, M.
    Garbini, M.
    Geis, C.
    Glueck, F.
    Grandi, L.
    Greene, Z.
    Grignon, C.
    Hasterok, C.
    Hannen, V.
    Hogenbirk, E.
    Howlett, J.
    Hilk, D.
    Hils, C.
    James, A.
    Kaminsky, B.
    Kazama, S.
    Kilminster, B.
    Kish, A.
    Krauss, L. M.
    Landsman, H.
    Lang, R. F.
    Lin, Q.
    Linde, F. L.
    Lindemann, S.
    Lindner, M.
    Lopes, J. A. M.
    Undagoitia, T. Marrodan
    Masbou, J.
    Massoli, F. V.
    Mayani, D.
    Messina, M.
    Micheneau, K.
    Molinario, A.
    Morå, Knut D.
    Stockholm University, Faculty of Science, Department of Physics.
    Morteau, E.
    Murra, M.
    Naganoma, J.
    Newstead, J. L.
    Ni, K.
    Oberlack, U.
    Pakarha, P.
    Pelssers, Bart
    Stockholm University, Faculty of Science, Department of Physics.
    de Perio, P.
    Persiani, R.
    Piastra, F.
    Piro, M. C.
    Plante, G.
    Rauch, L.
    Reichard, S.
    Rizzo, A.
    Rupp, N.
    Dos Santos, J. M. F.
    Sartorelli, G.
    Scheibelhut, M.
    Schindler, S.
    Schumann, M.
    Schreiner, J.
    Lavina, L. Scotto
    Selvi, M.
    Shagin, P.
    Silva, M. C.
    Simgen, H.
    Sissol, P.
    von Sivers, M.
    Thers, D.
    Thum, J.
    Tiseni, A.
    Trotta, R.
    Tunnell, C. D.
    Valerius, K.
    Vargas, M. A.
    Wang, H.
    Wei, Y.
    Weinheimer, C.
    Wester, T.
    Wulf, J.
    Zhang, Y.
    Zhu, T.
    Zuber, K.
    DARWIN: towards the ultimate dark matter detector2016In: Journal of Cosmology and Astroparticle Physics, ISSN 1475-7516, E-ISSN 1475-7516, no 11, article id 017Article in journal (Refereed)
    Abstract [en]

    DARk matter WImp search with liquid xenoN (DARWIN(2)) will be an experiment for the direct detection of dark matter using a multi-ton liquid xenon time projection chamber at its core. Its primary goal will be to explore the experimentally accessible parameter space for Weakly Interacting Massive Particles (WIMPs) in a wide mass-range, until neutrino interactions with the target become an irreducible background. The prompt scintillation light and the charge signals induced by particle interactions in the xenon will be observed by VUV sensitive, ultra-low background photosensors. Besides its excellent sensitivity to WIMPs above a mass of 5 GeV/c(2), such a detector with its large mass, low-energy threshold and ultra-low background level will also be sensitive to other rare interactions. It will search for solar axions,galactic axion-like particles and the neutrinoless double-beta decay of Xe-136, as well as measure the low-energy solar neutrino flux with <1% precision, observe coherent neutrino-nucleus interactions, and detect galactic supernovae. We present the concept of the DARWIN detector and discuss its physics reach, the main sources of backgrounds and the ongoing detector design and R&D efforts.

  • 20. Aalst, Will
    et al.
    Shaw, Michael J.Szyperski, ClemensStirna, JanisStockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.Persson, Anne
    The Practice of Enterprise Modeling: first IFIP WG 8.1 Working Conference (PoEM 2008), proceedings2009Conference proceedings (editor) (Other academic)
  • 21. Aalto, A
    et al.
    Nikkinen, J
    Peltomäki, Jarkko
    Vähämaa, S
    Profitability and Diversification Benefits of Momentum Strategies on Commodity Index Futures2011In: International Journal of Accounting and Finance, ISSN 1752-8232, Vol. 3, no 1, p. 21-32Article in journal (Refereed)
  • 22. Aalto, Juha
    et al.
    Riihimäki, Henri
    Meineri, Eric
    Hylander, Kristoffer
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Luoto, Miska
    Revealing topoclimatic heterogeneity using meteorological station data2017In: International Journal of Climatology, ISSN 0899-8418, E-ISSN 1097-0088, Vol. 37, no Suppl. 1, p. 544-556Article in journal (Refereed)
    Abstract [en]

    Climate is a crucial driver of the distributions and activity of multiple biotic and abiotic processes, and thus high-quality and high-resolution climate data are often prerequisite in various environmental research. However, contemporary gridded climate products suffer critical problems mainly related to sub-optimal pixel size and lack of local topography-driven temperature heterogeneity. Here, by integrating meteorological station data, high-quality terrain information and multivariate modelling, we aim to explicitly demonstrate this deficiency. Monthly average temperatures (1981-2010) from Finland, Sweden and Norway were modelled using generalized additive modelling under (1) a conventional (i.e. considering geographical location, elevation and water cover) and (2) a topoclimatic framework (i.e. also accounting for solar radiation and cold-air pooling). The performance of the topoclimatic model was significantly higher than the conventional approach for most months, with bootstrapped mean R-2 for the topoclimatic model varying from 0.88 (January) to 0.95 (October). The estimated effect of solar radiation was evident during summer, while cold air pooling was identified to improve local temperature estimates in winter. The topoclimatic modelling exposed a substantial temperature heterogeneity within coarser landscape units (>5 degrees C/1 km(-2) in summer) thus unveiling a wide range of potential microclimatic conditions neglected by the conventional approach. Moreover, the topoclimatic model predictions revealed a pronounced asymmetry in average temperature conditions, causing isotherms during summer to differ several hundreds of metres in altitude between the equator and pole facing slopes. In contrast, cold-air pooling in sheltered landscapes lowered the winter temperatures ca. 1.1 degrees C/100m towards the local minimum altitude. Noteworthy, the analysis implies that conventional models produce biassed predictions of long-term average temperature conditions, with errors likely to be high at sites associated with complex topography.