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  • 2701.
    Alentola, Anni Emilia
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Changing the narratives of marginalised bodies - a study about body positivism2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study is to explain and analyse the body positivity movement in the social media platform Instagram, as well as its empowering effects on women active in this movement. The phenomenon based on visuality, body positivism, has more than three million pictures on Instagram, hashtagged under two popular hashtags examined in this thesis: #bodypositivity and #bodypositive. The goal of this movement is to show diversity in the portrayal of women, as well as to encourage acceptance of all body types, skin colours and body flaws - especially marginalised bodies that are often invisible in the current society. The research is conducted with methods of visual content analysis and interviews with women participating in the body positivity movement. This study is framed in feminism theory and this study includes theories of gender-norms, Western beauty standards, the male gaze and questions about identity and body image. The results of this study show that most of the people participating in the movement are white women and are pictured often in their underwear. In the pictures hashtagged with body positivity related hashtags, there are, however, not that many flaws visible - such as cellulite or stretch marks. Nevertheless, after interviewing the women active in this movement - active as picture publishers, conversation holders and as body positive Instagram-user followers - this movement is empowering to the women and helps develop a positive body image and better self-esteem. In addition, this phenomenon can change the narratives of the people with marginalised bodies and modify the image of how women are represented and portrayed in society.

  • 2702. ALEPH, The
    et al.
    ,
    ,
    ,
    Collaborations, SLD
    LEP Electroweak Working Group, the
    SLD Electroweak and Heavy Flavour Groups, the
    Precision Electroweak Measurements on the Z Resonance2006In: Physics Reports, Vol. 427, p. 257-Article in journal (Refereed)
  • 2703.
    Alesini, Anna
    Stockholm University, Faculty of Law, Department of Law.
    Riskplacering vid avtalets återgång enligt köplagen2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 2704.
    Aleson, Dan
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    En effectiveness-studie av KBT-behandlingar för GAD på en specialistmottagning2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Objective: While the efficacy of Dugas and Robichauds (2007) CBT treatment model for GAD has been tested in clinical trials, it is still unclear how the treatment is received in a outpatient setting with clinically referred patients. The present effectiveness study aimed to examine the effect of Dugas and Robichauds (2007) CBT treatment on a large outpatient group (N=188) diagnosed with GAD. In addition other types of CBT treatments delivered to the outpatient group were examined, as well as potential moderators for treatment effect such as age, sex, initial GAD-7 scores and concurrent pharmacological treatment. The treatment for the outpatient group was delivered in a clinic (WeMind, www.wemind.se) specialized in treatments of depression and anxiety.  Method: The study is an analysis of gathered data from CBT treatments of GAD during a 3 year span at the clinic. Patients (N=188) diagnosed with GAD were categorized according to type of CBT treatment received and if treatment was completed with intact data. 71 patients were treated with Dugas and Robichauds (2007) CBT treatment, but 22 of these patients also received other CBT interventions at the same time. 33 patients received other kinds of CBT treatment. A large group (N=84) had missing data or did not complete treatment. Measurements taken at the beginning and end of treatment were Generalized Anxiety Disorder scale-7 (GAD-7), Public Health Questionnaire-9  (PHQ-9) and Penn State Worry Questionnaire (PSWQ). Clinical remission was measured at the end of treatment with the help of the therapists. A completeranalysis design was used with no waitlist or control group. Results: A paired samples T-test for patients treated with Dugas and Robichauds (2007) CBT treatment and measured with GAD-7 and PHQ-9 gave significant results for GAD-7, t70=13,17 (p<0.001) and PHQ-9, t67=10,25 (P<0.001). 46 of the 71 patients (65%) was assessed with clinical remission (no clinical diagnoses after treatment). Effectsize calculated with Cohen's d were GAD-7=1.76, PHQ-9=1.46 and PSWQ=1.76. Moderators were examined by calculating GAD-7 change score (difference pre-post GAD-7) and correlating the change score with age, sex, initial GAD-7 score and pharmacological treatment. Age and sex gave no significant results. Whether concurrent pharmacological treatment had an moderator effect was examined by categorizing the patients into three groups: (1) no pharmacological treatment, (2) stable pharmacological treatment and (3) changed pharmacological treatment (increased dosage or new treatment). Again no significant effect was found. One positive significant correlation was found with initial GAD-7 scores and GAD-7 change score, GAD-7, r=.66, t69=7,36 (p<0.001). Higher initial GAD-7 measurement correlated with a greater change score. Conclusions:The results indicate a large treatment effect for Dugas and Robichauds (2007) CBT treatment model for GAD in an normal outpatient setting, with clinically referred patients and treatment administered by general CBT therapists. The effect was superior compared to the group that received general CBT treatment interventions for GAD. The effect of treatment measured with GAD-7 and PHQ-9 was also drastically improved if other CBT interventions was added to the treatment model, but these interventions did not have an effect on clinical remission. Serious limitations such as a high percentage of drop outs, a completeranalysis model, no control group and no follow up data restrict the possible interpretations of the results.

  • 2705.
    Alestedt, Mathias
    Stockholm University, Faculty of Social Sciences, School of Business.
    A Case Study of Currency Exposure2000Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this case study thesis I investigate how currency fluctuations might affect companies and to what degree it is possible for a normal stock- or bondholder to estimate the impacts from currency fluctuations.

  • 2706.
    Alestig Blomqvist, Peter
    Stockholm University, Faculty of Humanities, Department of Media Studies.
    Från folkmord till pressfrihet?: En studie av medieklimatet i Rwanda 19 år efter folkmordet2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    1994 genomfördes ett av de mest brutala folkmord som världen har skådat. Platsen var Rwanda, ochlandets medier spelade en avgörande roll i att hetsa folkgruppen hutuer mot tutsier. Den här studien utfördes i Sverige och Rwanda 19 år efter att folkmordet startade, under våren2013, med syftet att undersöka hur medieklimatet i landet ser ut i dag. Totalt sju informanterintervjuades, varav två exiljournalister som i dag befinner sig i Sverige och fem journalister iRwanda. Frågeställningarna var som följer: 1) Hur kan det rwandiska medieklimatet klassificeras,utifrån intervjuer med rwandiska journalister? 2) Hur kan den rwandiska medieetiken beskrivas,utifrån intervjuer med rwandiska journalister? 3) Hur påverkar de rwandiska exiljournalisternamedieklimatet i landet, enligt de rwandiska journalisterna?Som teoretisk grund i studien används dels teorier om offentlighet, dels teorier omklassificering av mediesystem och dels normativa teorier om medieetik. Utifrån intervjuernaanalyseras och diskuteras hur mediesystemet i Rwanda ser ut i dag, hur det kan klassificeras, hurmedieetiken ser ut, vilken påverkan exiljournalisterna kan tänkas ha på utvecklingen avmedieklimatet – och avslutningsvis, vart Rwandas medieklimat kan tänkas vara på väg. Resultaten av studien visar att mediesystemet i Rwanda först och främst är i konstantförändring. De senaste åren har, att döma av de fem inhemska journalisternas syn på saken, flerasteg tagits mot ett öppnare medieklimat. I dag har det flera likheter med länder som hör hemma iHallin & Mancinis (2004) Polarized Pluralist Model. Men det är lång väg kvar innan landet kansägas fylla samtliga kriterier, eller motsvarar de västliga ideal som finns inom journalistisk etik.Medierna är inte någon tredje statsmakt, de är fortfarande starkt begränsade och journalisterna ärfortfarande rädda i vissa situationer. Lågt förtroende för journalistkåren är ett problem. Brist påkompetens hos medierna och oseriösa aktörer är ytterligare ett problem som journalisterna pekar på.Samtidigt finns tecken på att medieklimatet fortsätter att röra sig i riktning mot ett mer västligtideal, även om det finns motstridiga krafter. Såväl teknikutveckling, till exempel genom ökatgenomslag av sociala medier, och indirekt påverkan från exiljournalister genom internationellaorganisationer, drar i riktningen mot ett öppnare medieklimat. Ytterligare en kraft är journalisternasegna utmaningar av de uttalade eller outtalade gränserna för yttrandefriheten. Att döma avjournalisternas svar är en stark kraft som verkar i den motsatta riktningen den politiskt oroligasituationen i regionen, med konflikten i grannlandet Kongo som största problem. Direkta hot ochvåld mot journalister har minskat de senaste åren, men rädslan finns kvar och leder till självcensur.

  • 2707. Aletta, F.
    et al.
    Axelsson, Östen
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Kang, J.
    Towards acoustic indicators for soundscape design2014In: Proceeding of Forum Acusticum 2014, 2014, article id SS31_10Conference paper (Other academic)
    Abstract [en]

    Scientific research on how people perceive, experience or understand the acoustic environment as a whole (i.e., soundscape) is still in development, both with regards to acoustic properties, as well as personality and individual differences. In order to predict how people would perceive an acoustic environment, it is central to identify the underlying acoustic properties of soundscapes. In this study these properties were approached by investigating the visual similarity of colour prints of 50 audio spectrograms (time vs. frequency), representing audio recordings of a variety of acoustic environments. In total, 15 female and 15 male students from the University of Sheffield were recruited to assess the 50 spectrograms by sorting them into groups based on how similar they were perceived to be. A distance matrix, derived from the sorting data, was subjected to a Multidimensional Scaling analysis to map the underlying dimensions of similarity among the spectrograms, which are proposed to represent the underlying acoustic properties of the corresponding acoustic environments. Three dimensions were identified. The first dimension relates to Distinguishable–Indistinguishable sound sources, the second dimension to Background–Foreground sounds, and the third dimension to Intrusive–Smooth sound sources. The results also show that established acoustic parameters are inappropriate as indicators of acoustic environments and that further research is needed in this field.

  • 2708. Aletta, Francesco
    et al.
    Axelsson, Östen
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Kang, Jian
    Dimensions Underlying the Perceived Similarity of Acoustic Environments2017In: Frontiers in Psychology, ISSN 1664-1078, E-ISSN 1664-1078, Vol. 8, article id 1162Article in journal (Refereed)
    Abstract [en]

    Scientific research on how people perceive or experience and/or understand the acoustic environment as a whole (i.e., soundscape) is still in development. In order to predict how people would perceive an acoustic environment, it is central to identify its underlying acoustic properties. This was the purpose of the present study. Three successive experiments were conducted. With the aid of 30 university students, the first experiment mapped the underlying dimensions of perceived similarity among 50 acoustic environments, using a visual sorting task of their spectrograms. Three dimensions were identified: (1) Distinguishable-Indistinguishable sound sources, (2) Background-Foreground sounds, and (3) Intrusive-Smooth sound sources. The second experiment was aimed to validate the results from Experiment 1 by a listening experiment. However, a majority of the 10 expert listeners involved in Experiment 2 used a qualitatively different approach than the 30 university students in Experiment 1. A third experiment was conducted in which 10 more expert listeners performed the same task as per Experiment 2, with spliced audio signals. Nevertheless, Experiment 3 provided a statistically significantly worse result than Experiment 2. These results suggest that information about the meaning of the recorded sounds could be retrieved in the spectrograms, and that the meaning of the sounds may be captured with the aid of holistic features of the acoustic environment, but such features are still unexplored and further in-depth research is needed in this field.

  • 2709. Aletta, Francesco
    et al.
    Kang, Jian
    Axelsson, Östen
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics. University of Sheffield, United Kingdom.
    Soundscape descriptors and a conceptual framework for developing predictive soundscape models2016In: Landscape and Urban Planning, ISSN 0169-2046, E-ISSN 1872-6062, Vol. 149, p. 65-74Article in journal (Refereed)
    Abstract [en]

    Soundscape exists through human perception of the acoustic environment. This paper investigates how soundscape currently is assessed and measured. It reviews and analyzes the main soundscape descriptors in the soundscape literature, and provides a conceptual framework for developing predictive models in soundscape studies. A predictive soundscape model provides a means of predicting the value of a soundscape descriptor, and the blueprint for how to design soundscape. It is the key for implementing the soundscape approach in urban planning and design. The challenge is to select the appropriate soundscape descriptor and to identify its predictors. The majority of available soundscape descriptors are converging towards a 2-dimensional soundscape model of perceived affective quality (e.g., Pleasantness–Eventfulness, or Calmness–Vibrancy). A third potential dimension is the appropriateness of a soundscape to a place. This dimensions provides complementary information beyond the perceived affective quality. However, it depends largely on context, and because a soundscape may be appropriate to a place although it is poor, this descriptor must probably not be used on its own. With regards to predictors, or soundscape indicators, perceived properties of the acoustic environment (e.g., perceived sound sources) are winning over established acoustic and psychoacoustic metrics. To move this area forward it is necessary that the international soundscape community comes together and agrees on relevant soundscape descriptors. This includes to agree on numerical scales and assessment procedures, as well as to standardize them.

  • 2710. Aletta, Francesco
    et al.
    Margaritis, Efstathios
    Filipan, Karlo
    Puyana Romero, Virginia
    Axelsson, Östen
    Stockholm University, Faculty of Social Sciences, Department of Psychology, Perception and psychophysics.
    Kang, Jian
    Characterization of the soundscape in Valley Gardens, Brighton, by a soundwalk prior to an urban design intervention2015In: Proceedings of Euronoise 2015 / [ed] C. Glorieux, Nederlands Akoestisch Genootschap and ABAV - Belgian Acoustical Society , 2015, p. 1547-1552, article id 357Conference paper (Other academic)
    Abstract [en]

    The purpose of the present study was to characterize the soundscape of the Valley Gardens in Brighton before the area is converted into a downtown park. Valley Gardens is located in the busy city centre. It extends from the Brighton Pier at the seafront and approximately 1.5 km to the north. It includes Old Stein, Victoria Gardens, St Peter’s Church, and The Level. In 2015 work will commence on redeveloping Victoria Gardens and St Peter’s Church. In order to characterize the soundscape of the Valley Gardens prior to this urban design intervention a soundwalk was conducted. In October 2014, a group of 21 persons -experts in acoustics and officers of the City Council- were guided through the area together, and assessed the soundscape at eight sites: five within the Valley Gardens and three reference sites. The assessments covered the soundscape quality, how appropriate the soundscape is to the place, the dominance of perceived sound sources, and the affective quality of the soundscape. In addition, binaural recordings and sound-level measurements were conducted at each of the eight sites during the soundwalk. Preliminary results indicate that the Valley Gardens was dominated by the sound of road traffic, and that the soundscape was perceived as inappropriate to the place. Consequently, the planned design intervention should reduce the dominance of road-traffic sound and introduce more positive sounds, like the sound of people and nature. This would be done through careful planning of the landscape and human activities within the area. The plan is to follow-up these results with a post-intervention soundwalk.

  • 2711.
    Alevronta, Eleftheria
    et al.
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Ahlberg, Alexander
    Mavroidis, Panayiotis
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    al-Abany, Massoud
    Friesland, Signe
    Tilikidis, Aris
    Laurell, Goran
    Lind, Bengt K.
    Stockholm University, Faculty of Science, Medical Radiation Physics (together with KI).
    Dose-response relations for stricture in the proximal oesophagus from head and neck radiotherapy2010In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 97, no 1, p. 54-59Article in journal (Refereed)
    Abstract [en]

    Background and purpose: Determination of the dose-response relations for oesophageal stricture after radiotherapy of the head and neck. Material and methods: In this study 33 patients who developed oesophageal stricture and 39 patients as controls are included. The patients received radiation therapy for head and neck cancer at Karolinska University Hospital, Stockholm, Sweden. For each patient the 3D dose distribution delivered to the upper 5 cm of the oesophagus was analysed. The analysis was conducted for two periods, 1992-2000 and 2001-2005, due to the different irradiation techniques used. The fitting has been done using the relative seriality model. Results: For the treatment period 1992-2005, the mean doses were 49.8 and 33.4 Gy, respectively, for the cases and the controls. For the period 1992-2000, the mean doses for the cases and the controls were 49.9 and 45.9 Gy and for the period 2001-2005 were 49.8 and 21.4 Gy. For the period 2001-2005 the best estimates of the dose-response parameters are D-50 = 61.5 Gy (52.9-84.9 Gy), gamma = 1.4 (0.8-2.6) and s = 0.1 (0.01-0.3). Conclusions: Radiation-induced strictures were found to have a dose response relation and volume dependence (low relative seriality) for the treatment period 2001-2005. However, no dose response relation was found for the complete material.

  • 2712. Alexakis, A.
    et al.
    Bäckvall, Jan-Erling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Krause, N.
    Pàmies, O.
    Diéguez, M.
    Enantioselective copper-catalyzed conjugate addition and allylic substitution reactions2008In: Chemical Reviews, ISSN 0009-2665, Vol. 108, no 8, p. 2796-2823Article in journal (Refereed)
  • 2713.
    Alexander, Ezra
    Stockholm University, Faculty of Humanities, Department of English.
    Transmedial Migration: Properties of Fictional Characters Adapted into Actual Behavior2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Research in the field of fictional and possible worlds examines the real and its hypothetical counterparts. The interaction between the actual and the fictional is a cause of debate within this field, and includes questions concerning the ontological status of fictional characters and their relation to reality. The following discussion will engage current positions in this debate. These include questions of reference regarding the correlation between fictional characters and actual personalities. Studying the transmedial migration of character properties from fictional worlds into the actual world engages with the possible as dependent on the actual, as well as the influence fiction can have on reality, by demonstrating how individual characters are perceived as packages of properties, some of which we identify and recognize as adaptable to our own behavior. Transmedial migration requires compatibility between different media. Accordingly, it is explained through the direct correspondence of fictional properties to actual properties, and the indirect correspondence of fictional characters to actual people. I am claiming that an interaction can be observed between different media, such as fictional worlds and the actual world, with particular emphasis on the example of fictional characters and their properties. In order to comprehend this we need a robust framework and the model that I am proposing here comprises the essential elements for such a framework. The transmedial migration of character properties from a textual medium, such as a Sherlock Holmes story, into the physical, social medium of the actual world is the action of adapting a fictional character’s package of properties into an actual person’s behavior. The agency of actual people in adapting fictional character properties to their corporal, social actions is what constitutes transmedial migration. This is a specific example of behavioral learning that recognizes certain behavior by the means of a label or trademark that is acquired from a fictional character. It is conceivable that any number of behavioral attributes, such as attitudes or habits, could be scientifically proven to have transmedially migrated by means of experimentation. Nevertheless, culturally and socially, it is only the definite identification of such character properties that substantiates my argument of transmedial migration through adaptation.

  • 2714. Alexander, Jan
    et al.
    Benford, Diane
    Boobis, Alan
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Scientific Opinion on Hexabromocyclododecanes (HBCDDs) in Food2011In: EFSA Journal, ISSN 1831-4732, Vol. 9, no 7, p. 2296-Article in journal (Other academic)
    Abstract [en]

    EFSA was asked by the European Commission to deliver a scientific opinion on hexabromocyclododecanes (HBCDDs) in food. HBCDDs are additive flame retardants primarily used in expanded and extruded polystyrene applied as construction and packing materials, and in textiles. Technical HBCDD predominantly consists of three stereoisomers (α-, β- and γ-HBCDD). Also δ- and ε-HBCDD may be present but at very low concentrations. HBCDDs are present in the environment and likewise in biota and in food and feed. Data from the analysis of HBCDDs in 1,914 food samples were provided to EFSA by seven European countries, covering the period from 2000 to 2010. The Panel on Contaminants in the Food Chain (CONTAM Panel) selected α-, β- and γ-HBCDD to be of primary interest. Since all toxicity studies were carried out with technical HBCDD, a risk assessment of individual stereoisomers was not possible. Main targets were the liver, thyroid hormone homeostasis and the reproductive, nervous and immune systems. HBCDDs are not genotoxic. The CONTAM Panel identified neurodevelopmental effects on behaviour as the critical endpoint, and derived a benchmark dose lower confidence limit for a benchmark response of 10 % (BMDL10) of 0.79 mg/kg body weight. Due to the limitations and uncertainties in the current data base, the CONTAM Panel concluded that it was inappropriate to use this BMDL to establish a health based guidance value, and instead used a margin of exposure (MOE) approach for the health risk assessment of HBCDDs. Since elimination characteristics of HBCDDs in animals and humans differ, the Panel used the body burden as starting point for the MOE approach. The CONTAM Panel concluded that current dietary exposure to HBCDDs in the European Union does not raise a health concern. Also additional exposure, particularly of young children, to HBCDDs from house dust is unlikely to raise a health concern

  • 2715. Alexander, Jan
    et al.
    Benford, Diane
    Boobis, Alan
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Scientific Opinion on Polybrominated Diphenyl Ethers (PBDEs) in Food2011In: EFSA Journal, ISSN 1831-4732, Vol. 9, no 5, p. 2156-Article in journal (Other academic)
  • 2716. Alexander, Jan
    et al.
    Benford, Diane
    Boobis, Alan
    Bergman, Åke
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Environmental Chemistry.
    Scientific Opinion on Tetrabromobisphenol A (TBBPA) and its derivatives in food: EFSA Panel on Contaminants in the Food Chain (CONTAM)2011In: EFSA Journal, ISSN 1831-4732, Vol. 9, no 12, p. 2477-Article in journal (Refereed)
    Abstract [en]

    EFSA was asked by the European Commission to deliver a scientific opinion on tetrabromobisphenol A (TBBPA) and its derivatives in food. TBBPA and its derivatives are widely used as flame retardants. TBBPA is primarily used as reactive flame retardant covalently bound to epoxy and polycarbonate resins. TBBPA derivatives are used as either reactive or additive intermediates in polymer manufacture. Data from the analysis of TBBPA in 344 food samples were submitted to EFSA by two European countries (Norway and Spain), covering the period from 2007 to 2010. All samples were in the food group “Fish and other seafood”, and all analytical results were reported as less than the limit of quantification (LOQ) (about 1 ng/g wet weight). Toxicological studies with TBBPA have been carried out using different experimental designs with single or repeated administration during gestation, postnatally or in adulthood. The main target is thyroid hormone homeostasis. TBBPA is not genotoxic. There are no indications that TBBPA might be carcinogenic. The Panel on Contaminants in the Food Chain (CONTAM Panel) identified a lower confidence limit for a benchmark response of 10 % (BMDL10) of 16 mg/kg b.w. reported for changes in thyroid hormones as the critical reference point. Due to the limitations and uncertainties in the database, the CONTAM Panel concluded that it was inappropriate to use this BMDL to establish a health based guidance value, and therefore used a margin of exposure (MOE) approach for the health risk assessment of TBBPA. In view of the large MOEs, the CONTAM Panel concluded that current dietary exposure to TBBPA in the European Union does not raise a health concern. Also exposure of infants via human milk does not raise a health concern. Additional exposure, particularly of young children, to TBBPA from house dust is unlikely to raise a health concern.

  • 2717.
    Alexander, John
    Stockholm University, Faculty of Humanities, Department of Media Studies, Cinema Studies.
    Screen play: audiovisual narrative & viewer interaction1999Doctoral thesis, monograph (Other academic)
    Abstract [en]

    How does the viewer, interact, with the on-screen narratives of film, television and computer? What new forms of interaction can be realised with the emerging narratives of CD-ROM and Internet?

    This study considers screen play in terms of the game the viewer plays with audiovisual narrative, and how the viewer negotiates with a story to interpret, revise and reconstruct new stories of their own.

    Aspects of game and narrative theories, cognitive psychology and phenomenology, as well as recent research in the fields of cinema, television and computer studies, are incorporated within a screen play theory, which positions the viewer both as player and storyteller. Thus, screen play can be defined as a fusion of the external screen narrative and the internal and individual scenario.

    In addressing the divide between player and game ?, the mystic gulf, between viewer and narrative ? a re-assessment of early film theory plays an important part in coming to terms with the fin du siècle playground represented by the cinematographe a century ago, and the digital IT playground of the present, and an emergent narrative, in whatever form it may take.

  • 2718. Alexander, Karen A.
    et al.
    Heymans, Johanna J.
    Magill, Shona
    Tomczak, Maciej T.
    Stockholm University, Faculty of Science, Stockholm University Baltic Sea Centre.
    Holmes, Steven J.
    Wilding, Thomas A.
    Investigating the recent decline in gadoid stocks in the west of Scotland shelf ecosystem using a foodweb model2015In: ICES Journal of Marine Science, ISSN 1054-3139, E-ISSN 1095-9289, Vol. 72, no 2, p. 436-449Article in journal (Refereed)
    Abstract [en]

    Abundance and biomass of cod, haddock, and whiting in the waters off of the west coast of Scotland (wcoS) have undergone large changes in recent years, most notably a recent decline. These three species contribute a considerable part of Scottish demersal landings from this area and as such it is important to understand why these stocks are behaving the way they are. A number of explanations for the decline have been proposed, including: seal predation, pressure from Nephrops trawls, and fishing pressure more generally. We used an ecosystem model of the wcoS continental shelf (<200 m depth) to investigate whether these proposed explanations for declining gadoid stocks are feasible. Results suggest that the rise in the grey seal population over recent years has not led to the decline in gadoid stocks; there is insufficient bycatch by the Nephrops fleet to have a large impact on gadoid stocks; however, fishing, as a key driver of the west of Scotland shelf ecosystem, has impacted stocks and by decreasing fishing levels to maximum sustainable yield cod biomass may increase slightly though not returning to previous levels. Although this means we are little further forward in understanding the cause of recent gadoid declines in the area, the development of this model has enabled us to further our knowledge and understanding of aspects of trophic structure and the impacts of fishing on the wcoS.

  • 2719.
    Alexander, Sahlström
    Stockholm University, Faculty of Social Sciences, Department of Human Geography.
    Vad hände med trädgårdsstaden?: En studie över planeringsteori och stadsideal i Stockholmsnordost kommunförbund2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inledningsvis uppkom denna studie från ett intresse över stadsidealet trädgårdsstaden och hur begrepp och teorier används i stadsplanering. Denna studie har ett fokus på stadsideal i Stockholms nordost kommunförbund, studien behandlar stadsidealet trädgårdsstaden och dess plats i planeringen. Begrepp och teorier centrala för studien bearbetas, men fokus har lagts på begreppet urban sprawl. Djupgående intervjuer utförs med planerare och arkitekter på Stockholms nordost kommunförbund samt Stockholms läns landsting för att sedan analysera källmaterialet med hjälp av innehållsanalys och kritisk diskursanalys (CDA). Detta görs för att på ett ingående sätt analysera vilka sociala praktiker och värderingar som styr stadsideal och planering i Stockholms nordost kommunförbund. Studien visar att det finns generella och specifika mål inom planeringen vilka inte är knutna tillspecifika stadsideal eller teori. Det centrala i diskursen är begrepp för bebyggelseutvecklingen. Det övergripande målet för planeringen är regionala stadskärnor som används i samband med specifika målsättningar och begrepp som förtätning, planera kollektivtrafiknära och hushållning av mark. Att integrera ny bebyggelse med befintlig är även det ett övergripande mål. Studien visar att trädgårdsstaden som stadsideal ses vara oförenligt med övergripande och specifika mål vilket medför att det inte behandlas som ett alternativ i bebyggelseutvecklingen. Urban sprawl som begrepp tolkas olika av respondenterna, men däremot ses lösningen på urban sprawl vara att planera kollektivtrafiknära och hushålla med mark.

  • 2720.
    Alexander, Steven M.
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. University of Maryland, USA; University of Waterloo, Canada.
    Andrachuk, Mark
    Armitage, Derek
    Navigating governance networks for community-based conservation2016In: Frontiers in Ecology and the Environment, ISSN 1540-9295, E-ISSN 1540-9309, Vol. 14, no 3, p. 155-164Article, review/survey (Refereed)
    Abstract [en]

    Governance networks can facilitate coordinated action and shared opportunities for learning among conservation scientists, policy makers, and communities. However, governance networks that link local, regional, and international actors just as often reflect social relationships and arrangements that can undermine conservation efforts, particularly those concerning community-level priorities. Here, we identify three waypoints or navigational guides to help researchers and practitioners explore these networks, and to inspire them to consider in a more systematic manner the social rules and relationships that influence conservation outcomes. These waypoints encourage those engaged in community-based conservation (CBC) to: (1) think about the networks in which they are embedded and the constellation of actors that influence conservation practice; (2) examine the values and interests of diverse actors in governance, and the implications of different perspectives for conservation; and (3) consider how the structure and dynamics of networks can reveal helpful insights for conservation efforts. The three waypoints we highlight synthesize an interdisciplinary literature on governance networks and provide key insights for conservation actors navigating the challenges of CBC at multiple scales and levels.

  • 2721.
    Alexander, Steven M.
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. National Socio-Environmental Synthesis Center, USA.
    Armitage, Derek
    Carrington, Peter J.
    Bodin, Örjan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Examining horizontal and vertical social ties to achieve social-ecological fit in an emerging marine reserve network2017In: Aquatic conservation, ISSN 1052-7613, E-ISSN 1099-0755, Vol. 27, no 6, p. 1209-1223Article in journal (Refereed)
    Abstract [en]

    Most MPA networks are designed only with ecological processes in mind to increase their conservation utility. However, since MPA networks often involve large geographic areas, they also affect and involve multiple actors, institutions, and policy sectors. A key challenge when establishing an effective MPA network is to align the social system' with the biophysical MPA network (the ecological system'). This challenge is often denoted as social-ecological fit'. Facilitating collaborative social interactions among various actors and stakeholders (social connectivity) is equally as important as accomplishing ecological connectivity. New analytical approaches are required to effectively examine this social' dimension of fit. An emerging marine reserve network in Jamaica and the recent invasion of Indo-Pacific lionfish are used as a case study to: (1) examine the extent to which horizontal and vertical social ties bring local and national actors together to collaborate, coordinate, and share knowledge; and (2) assess the extent to which different attributes and features of such multilevel social networks may enhance or inhibit particular aspects of social-ecological fit. Findings suggest that multilevel linkages have played the greatest role in relation to enhancing fit in the marine reserve network in the context of the recent lionfish invasion. However, the long-term propensity of the multi-actor and multilevel networks to enhance social-ecological fit is uncertain given the prevalence of weak social ties, lack of a culture of information sharing and collaboration, and limited financial resources.

  • 2722.
    Alexander, Steven M.
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. National Socio-Environmental Synthesis Center, USA.
    Bodin, Örjan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Barnes, Michele L.
    Untangling the drivers of community cohesion in small-scale fisheries2018In: International Journal of the Commons, ISSN 1875-0281, E-ISSN 1875-0281, Vol. 12, no 1, p. 519-547Article in journal (Refereed)
    Abstract [en]

    Sustainable fisheries require strong management and effective governance. However, small-scale fisheries (SSF) often lack formal institutions, leaving management in the hands of local users in the form of various governance approaches (e.g. local, traditional, or co-management). The effectiveness of these approaches inherently relies upon some level of cohesion among resource users to facilitate agreement on common policies and practices regarding common pool fishery resources. Understanding the factors driving the formation and maintenance of community cohesion in SSF is therefore critical if we are to devise more effective participatory governance approaches and encourage and empower decentralized, localized, and community-based resource management approaches. Here, we adopt a social relational network perspective to propose a suite of hypothesized drivers that lead to the establishment of social ties among fishers that build the foundation for community cohesion. We then draw on detailed data from Jamaica's small-scale fishery to empirically test these drivers by employing a set of nested exponential random graph models (ERGMs) based on specific structural building blocks (i.e. network configurations) theorized to influence the establishment of social ties. Our results demonstrate that multiple drivers are at play, but that collectively, gear-based homophily, geographic proximity, and leadership play particularly important roles. We discuss the extent to which these drivers help explain previous experiences, as well as their implications for future and sustained collective action in SSF in Jamaica and elsewhere.

  • 2723.
    Alexander, Steven M.
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre. National Socio-Environmental Synthesis Center, United States.
    Epstein, Graham
    Bodin, Örjan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Armitage, Derek
    Campbell, Donovan
    Participation in planning and social networks increase social monitoring in community-based conservation2018In: Conservation Letters, ISSN 1755-263X, E-ISSN 1755-263X, Vol. 11, no 5, article id e12562Article in journal (Refereed)
    Abstract [en]

    Biodiversity conservation is often limited by inadequate investments in monitoring and enforcement. However, monitoring and enforcement problems may be overcome by encouraging resource users to develop, endorse, and subsequently enforce conservation regulations. In this article, we draw upon the literature on common-pool resources and social networks to assess the impacts of participation and network ties on the decisions of fishers to voluntarily report rule violations in two Jamaican marine reserves. Data was collected using questionnaires administered through personal interviews with fishers (n = 277). The results suggest that local fishers are more likely to report illegal fishing if they had participated in conservation planning and if they are directly linked to community-based wardens in information sharing networks. This research extends well-established findings regarding the role and impacts of participation on biodiversity conservation by highlighting the importance of synergies between participation and social networks for voluntary monitoring of conservation regulations.

  • 2724.
    Alexander, Widerberg
    Stockholm University, Faculty of Social Sciences, Department of Sociology.
    Den Andre i svenska valmanifest: En kvalitativ studie av svenska valmanifest och andrafiering inom politisk diskurs2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats är en studie i hur andrafiering används inom Socialdemokraternas och Moderaternas valmanifest, med syfte att se hur det har använts i diskurser inom politisk kommunikation gentemot potentiella väljare, utifrån frågeställningar om vilken funktion det fyller och hur användningen har utvecklats över tid. Vidare lyfts också frågor om hur andrafiering som process går till och vilka som har kommit att konstrueras som Den Andre. För att kunna studera den politiska diskursen har jag utöver teorier om andrafiering och Den Andre, främst använt mig av Laclau & Mouffes diskursteori, som har ett socialkonstruvistiskt perspektiv på språk och diskurs, för att förstå vilka effekter den politiska diskursen kan ha för samhället. Datamaterialet bestod av Socialdemokraternas och Moderaternas valmanifest inför svenska riksdagsval under en 50-års period, från 1964–2014, med totalt 32 valmanifest. Texterna har kodats och analyserats med en kvalitativ innehållsanalys. Resultatet visar på hur det skett en förändring över tid i vilka som andrafieras i valmanifesten, och att även användningen har ändrat karaktär och kommit att få ett allt större utrymme i den politiska diskursen i valmanifesten.

  • 2725.
    Alexanderson, Helena
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Brattforsheden: Vad sanden kan berätta om dess historia2007Other (Other (popular science, discussion, etc.))
  • 2726.
    Alexanderson, Helena
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Optiskt stimulerad luminiscensdatering (OSL) av nedisningshistorien i södra och mellersta Sverige2008In: SGU-rapport 2008-9: FoU-seminarium vid SGU 4 mars 2008 Dokumentation, 2008, p. 40-Conference paper (Other academic)
  • 2727.
    Alexanderson, Helena
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Residual OSL signals from modern Greenlandic river sediments2007In: Geochronometria, ISSN 1897-1695, Vol. 26, p. 1-9Article in journal (Refereed)
    Abstract [en]

    Ripple-laminated sandy deposits at shallow water depths in four rivers on Jameson Land, East Greenland were sampled for optically stimulated luminescence (OSL) dating. Silt-sized grains have significantly higher equivalent doses (~1.1 Gy) than sand grains (~0.1 Gy). This suggests that coarse grain-size fractions are better bleached and more suitable than fine grains for OSL dating of glaciofluvial/fluvial sediments. A sample from a sidebar deposited during the spring flood yielded 1.0 Gy (~500 years) while a subaerial deposit was completely zeroed. The spring flood deposit is considered to be most similar to deglacial conditions and incomplete bleaching of this amount (1 Gy) is generally not a significant source of error for sediments of Pleistocene age. Most samples have rather poor luminescence characteristics and are affected by thermal transfer if preheat temperatures at or above 260°C are used.

  • 2728.
    Alexanderson, Helena
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Sub-till glaciofluvial sediments at Hultsfred, South Swedish Upland2010In: GFF, ISSN 1103-5897, E-ISSN 2000-0863, Vol. 132, no 3&4, p. 153-159Article in journal (Refereed)
    Abstract [en]

    In a gravel pit near Hultsfred, at the eastern margin of the South Swedish Upland, gravelly, sandy and silty-sandy beds covered by a thick, strati?ed gravelly diamicton are exposed. Large folds and shear-planes indicate post-depositional deformation of the sorted sediments, which according to OSL dating have a maximum Middle Weichselian (,60 ka) age. The sand and gravel are interpreted as glacio?uvial sediments that were deposited laterally during a Middle Weichselian deglaciation, or possibly subglacially during the Late Weichselian. The large-scale deformation was due to glaciotectonics, caused by an overriding wet-based ice sheet during the last deglaciation. The subglacial hydrostatical pressure was high and led to the formation of downward-injected clastic dykes. A basal till, which forms the cover moraine in the area, caps the succession. The fairly frequent occurrence of sub-till sediments on the South Swedish Upland demonstrates the limited effect of glacial erosion in parts of this area. During the Last Glacial Maximum, the South Swedish Upland was an ‘island’ of slow-moving, polythermal and at least partly non-erosive ice, surrounded by faster ice-streams in the Baltic and in the Skagerrak. The ice sheet may have left its main impact on the landscape during short periods during advance and deglaciation only.

  • 2729. Alexanderson, Helena
    et al.
    Backman, Jan
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Cronin, Thomas M.
    Funder, Svend
    Ingólfsson, Ólafur
    Jakobsson, Martin
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Landvik, Jon Y.
    Löwemark, Ludvig
    Mangerud, Jan
    März, Christian
    Möller, Per
    O'Regan, Matthew
    Stockholm University, Faculty of Science, Department of Geological Sciences.
    Spielhagen, Robert F.
    An Arctic perspective on dating Mid-Late Pleistocene environmental history2014In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 92, p. 9-31Article in journal (Refereed)
    Abstract [en]

    To better understand Pleistocene climatic changes in the Arctic, integrated palaeoenvironmental andpalaeoclimatic signals from a variety of marine and terrestrial geological records as well as geochronologicage control are required, not least for correlation to extra-Arctic records. In this paper we discuss,from an Arctic perspective, methods and correlation tools that are commonly used to date ArcticPleistocene marine and terrestrial events. We review the state of the art of Arctic geochronology, withfocus on factors that affect the possibility and quality of dating, and support this overview by examples ofapplication of modern dating methods to Arctic terrestrial and marine sequences.Event stratigraphy and numerical ages are important tools used in the Arctic to correlate fragmentedterrestrial records and to establish regional stratigraphic schemes. Age control is commonly provided byradiocarbon, luminescence or cosmogenic exposure ages. Arctic Ocean deep-sea sediment successionscan be correlated over large distances based on geochemical and physical property proxies for sedimentcomposition, patterns in palaeomagnetic records and, increasingly, biostratigraphic data. Many of theseproxies reveal cyclical patterns that provide a basis for astronomical tuning.Recent advances in dating technology, calibration and age modelling allow for measuring smallerquantities of material and to more precisely date previously undatable material (i.e. foraminifera for 14C,and single-grain luminescence). However, for much of the Pleistocene there are still limits to the resolutionof most dating methods. Consequently improving the accuracy and precision (analytical andgeological uncertainty) of dating methods through technological advances and better understanding ofprocesses are important tasks for the future. Another challenge is to better integrate marine andterrestrial records, which could be aided by targeting continental shelf and lake records, exploringproxies that occur in both settings, and by creating joint research networks that promote collaborationbetween marine and terrestrial geologists and modellers.

  • 2730.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Eskola, Kari O
    Helmens, Karin F
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Optical dating of a Late Quaternary sediment sequence from Sokli, northern Finland2008In: Geochronometria, Vol. 32, p. 51-59Article in journal (Refereed)
    Abstract [en]

    Interstadial and non-glacial stadial sediments collected in boreholes from Sokli in northeastern Finland have been dated by optically stimulated luminescence on quartz and feldspar grains. The quartz OSL ages follow stratigraphic order, with one exception, and support the litho- and biostratigraphical correlation with the NW European mainland climate-stratigraphy and the marine oxygen-isotope stages. Feldspar IRSL dates generally overestimate the age, probably due to incomplete bleaching.

    The data show that during the last glacial cycle northeastern Finland was not glaciated until MIS 5b, around 90 ka. Interstadial conditions occurred around ~94 ka (MIS 5c), ~74-80 ka (MIS 5a) and 42-54 ka (MIS 3).

    The OSL ages have large standard errors mainly due to small sample sizes, relatively poor luminescence characteristics and uncertainties in dose-rate determinations.

  • 2731.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Henriksen, Mona
    Landvik, Jon Y
    Ryen, Heidi T
    Chronologies of the glacial history of Svalbard – a review2010In: Arctic Palaeoclimate and its Extremes (APEX) abstract volume, 2010, p. 21-21Conference paper (Other academic)
    Abstract [en]

    The basis of the glacial history of Svalbard lies in stratigraphic studies of terrestrial and marine geological records. Classic litho- and biostratigraphy give us local relative chronologies of events but to compare with other areas and records we are dependent on absolute age control.

     

    This presentation will focus on the Middle to Late Quaternary terrestrial record to which a range of different absolute dating techniques have been applied; these techniques all have their pros and cons regarding materials, resolution, age range, etc. Amino acid chronology, although not a strictly absolute dating method, may provide some age inferences. Radiocarbon dating of organic material such as shell and bone is still the most common technique and one that is generally considered reliable. It is however limited by its age range to the last ~50 ka, and our interest goes further back than so. Various versions of luminescence dating, particularly optically stimulated luminescence (OSL), have therefore become strong contenders during the recent decade, mainly due to their longer age range and applicability to a wider range of deposits than radiocarbon dating. Luminescence dating nevertheless has its drawbacks too, for Svalbard these are mainly related to the risk of incomplete bleaching (leading to age overestimation) and poor resolution (leading to large uncertainties for final ages). Other techniques that have been used on fossil material include electron spin resonance (ESR) and uranium-thorium (U/Th) dating. In common for most techniques is that we cannot date glacial events, but the intervening non-glacial (interstadial, interglacial) episodes. Cosmogenic exposure dating is an exception, which is also able to provide information on the thickness of ice sheets through time.

     

    From a geologist’s point of view we will discuss these different techniques, their usefulness and what we can expect of them. Do the dating methods meet our wishes regarding resolution? Are results from different methods comparable? The discussion will be based on our experience from the ongoing SciencePub project (www.ngu.no/sciencepub) and on literature and we will show examples of method applications and comparisons.

  • 2732.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Håkansson, Lena
    Dating the glacial history of northeast Greenland2007In: First Conference on Arctic Palaeoclimate and its Extremes, 2007Conference paper (Other (popular science, discussion, etc.))
  • 2733.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Johnsen, Timothy
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Murray, Andrew S.
    Nordic Laboratory for Luminescence Dating, Department of Earth Sciences, Aarhus University Risø DTU, DK-4000 Roskilde, Denmark .
    Re-dating the Pilgrimstad Interstadial with OSL: a warmer climate and a smaller ice sheet during the Swedish Middle Weichselian (MIS 3)?2010In: Boreas, ISSN 0300-9483, E-ISSN 1502-3885, Vol. 39, no 2, p. 367-376Article in journal (Refereed)
    Abstract [en]

    Pilgrimstad in central Sweden is an important locality for reconstructing environmental changes during the last glacial period (the Weichselian). Its central location has implications for the Scandinavian Ice Sheet as a whole. The site has been assigned an Early Weichselian age (marine isotope stage (MIS) 5 a/c; >74 ka), based on pollen stratigraphic correlations with type sections in continental Europe, but the few absolute dating attempts so far have given uncertain results. We re-excavated the site and collected 10 samples for optically stimulated luminescence (OSL) dating from mineral- and organic-rich sediments within the new Pilgrimstad section. Single aliquots of quartz were analysed using a post-IR blue single aliquot regenerative-dose (SAR) protocol. Dose recovery tests were satisfactory and OSL ages are internally consistent. All, except one from an underlying unit that is older, lie in the range 52–36 ka, which places the interstadial sediments in the Middle Weichselian (MIS 3); this is compatible with existing radiocarbon ages, including two measured with accelerator mass spectrometry (AMS). The mean of the OSL ages is 44±6 ka (n=9). The OSL ages cannot be assigned to the Early Weichselian for all reasonable adjustments to water content estimates and other parameters. The new ages suggest that climate was relatively mild and that the Scandinavian Ice Sheet was absent or restricted to the mountains for at least parts of MIS 3. These results are supported by other recent studies completed in Fennoscandia.

  • 2734.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Landvik, Jon Y.
    Ryen, Heidi T.
    Chronology and styles of glaciation in an inter-fjord setting, northwestern Svalbard2011In: Boreas, ISSN 0300-9483, E-ISSN 1502-3885, Vol. 40, no 1, p. 175-197Article in journal (Refereed)
    Abstract [en]

    A 30-m-thick sedimentary succession at Leinstranda on the southwestern coast of Brøggerhalvøya, northwestern Svalbard, spans the two last glacial–interglacial cycles and reveals information on glacial dynamics, sea-level changes and the timing of these events. We investigated the deposits using standard stratigraphical and sedimentological techniques, together with ground-penetrating radar, and established an absolute chronology based mainly on optically stimulated luminescence dating. We identi?ed facies associations that represent depositional settings related to advancing, overriding and retreating glaciers, marine and littoral conditions and periglacial surfaces. The environmental changes show an approximate cyclicity and reflect glaciations followed by high sea levels and later regression. The luminescence chronology places sea-level highstands at 185±8 ka, 129±10 ka,99±8 ka and 36±3 ka. These ages constrain the timing of recorded glaciations at Leinstranda to prior to c. 190 ka, between c. 170 and c. 140 ka (Late Saalian) and between c. 120 ka and c. 110 ka (Early Weichselian). The glaciations include phases with glaciers from three different source areas. There is no positive evidence for either Middle or Late Weichselian glaciations covering the site, but there are hiatuses at those stratigraphic levels. A high bedrock ridge separates Leinstranda from the palaeo-ice stream in Kongsfjorden, and the deposits at Leinstranda reflect ice-dynamic conditions related to ice-sheet evolution in an inter-fjord area. The environmental information and theabsolute chronology derived from our data allow for an improved correlation with the marine record, and for inferences to be made about the interaction between land, ocean and ice during the last glacial–interglacial cycles.

  • 2735.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Murray, Andrew
    Problems and potential of OSL-dating deglacial and interstadial sediments in Sweden2009Conference paper (Other academic)
    Abstract [en]

    Several recent OSL-ages from Sweden have been inconsistent with geological interpretation, commonly due to age overestimation, and have been met with some scepticism. We explore the problems and potential of OSL-dating in Sweden by analysing quartz OSL-ages from several known-age deglacial sites in southern and central Sweden and by investigating their luminescence properties. Two problems for obtaining good and reliable ages are incomplete bleaching and low-sensitivity quartz. Incomplete bleaching is partly, but not entirely, the cause of age overestimation and can be avoided by selecting suitable sediment facies. Low sensitivity leads to practical problems in measurements and larger uncertainties in dose estimates. On the other hand, potential for good OSL-dating is shown by high-sensitivity quartz from sites that contain both Dala sandstone clasts and sediments that may have had extensive reworking during the Quaternary.

    This knowledge is useful for interpreting OSL-results from unknown-age interstadial sites. Most interstadial sites in Sweden contain only fragmentary records and represent single events and OSL-ages from such sites lack a context to which the results can be related. It is for example rarely possible to get OSL-samples from a stratigraphic succession that spans a significantly longer time than the resolution of the method or find sites where dates from more than one stratigraphically overlying interglacial, interstadial or deglacial bed can be compared. As interstadial OSL-ages thus largely have to stand on their own, multiple samples and detailed data analyses are necessary to give credibility to the results given the Swedish record of OSL-difficulties. From a luminescence point of view, sites fulfilling the positive criteria identified for deglacial deposits should be selected, but the setting and nature of the most geologically interesting interstadial sites are not always obliging.

  • 2736.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Murray, Andrew
    Småland, south Sweden – a bleak place for luminescence dating or an area that will change Scandinavian glacial history?2007In: 9th International Conference “Methods of absolute chronology”, 2007Conference paper (Other (popular science, discussion, etc.))
  • 2737.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology (INK).
    Murray, Andrew S
    Problems and potential of OSL dating Weichselian and Holocene sediments in Sweden2010In: Abstracts and Proceedings of the Geological Society of Norway, NGF Number 1, 2010, 2010, p. 3-4Conference paper (Other academic)
    Abstract [en]

    Recent OSL dating of various Late Quaternary deposits in Sweden has resulted in several sets of ages that appear inconsistent with geological interpretation; they usually overestimate the expected age. We explore the problems and potential of OSL dating in Sweden by analysing quartz OSL-ages from several known-age sites in Sweden and by investigating their luminescence properties. Two difficulties in obtaining accurate and precise ages are incomplete bleaching and low-sensitivity quartz. Incomplete bleaching can give rise to age overestimation, but the importance of this effect can be minimised by selecting suitable sediment facies, although for some settings unexplained overestimates still remain. Low quartz OSL sensitivity leads to practical problems in measurements and larger uncertainties in dose estimates, but not necessarily to systematic age overestimation. Sites that contain Dala sandstone clasts and/or sediments that may have had extensive reworking during the Quaternary seem to provide high-sensitivity quartz. We consider such sites to show the most potential for accurate and precise OSL-dating in Sweden.

    For typical Swedish material, the scatter in doses makes OSL-ages less precise and the method cannot usually compete with radiocarbon dating for young (Late Weichselian-Holocene) sediments unless the deposits simply lack organic material. The lowest overall uncertainty for the samples in this study is 4% of the age (average is 7%) and we expect that OSL ages from Sweden cannot be much better known than this. A 5-10% precision in age is, however, usually not a problem for older sediments and OSL can advantageously be used to date for example interstadial deposits. Nevertheless, given the Swedish record of OSL-difficulties it is important to work with multiple samples and adapt analytical protocols to each site or sample to give credibility to the results.

  • 2738.
    Alexanderson, Helena
    et al.
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Murray, Andrew S.
    Was southern Sweden ice free at 19–25 ka, or were the post LGM glacifluvial sediments incompletely bleached?2007In: Quaternary Geochronology, ISSN 1871-1014, Vol. 2, no 1-4, p. 229-236Article in journal (Other (popular science, discussion, etc.))
    Abstract [en]

    Glacifluvial deposits along an ice-marginal zone in Småland, southern Sweden, have been dated using post-IR blue OSL. To test for incomplete bleaching, we adopted two strategies: analysis of modern analogues and small-aliquot dose distributions. Samples of modern fluvial sediments show no significant incomplete bleaching; they yield equivalent doses of only 0.5-2 Gy (~0.25-4% of our glacifluvial sediment doses). Small-aliquot dose distributions do not provide any evidence for incomplete bleaching. The sediments are believed to have been deposited during deglaciation and appear to fall into two age groups: 19-25 ka (mainly sandur sediments) and 33-73 ka (mainly deltaic sediments). Compared to the expected ages (13-15 ka), even the younger glacifluvial OSL ages appear up to 10 000 years (~25 Gy) too old. The ages are nevertheless stratigraphically consistent and correspond between sites; we deduce that the 19-25 ka ages are true deposition ages. For glacifluvial sedimentation to take place on the South Swedish Upland at this time either a very early deglaciation is required, or alternatively ice-free conditions just prior to the LGM. The deltaic sediments (33-73 ka) were most likely not significantly bleached during deposition and thus they date events prior to the latest ice advance.

  • 2739. Alexanderson, K.
    et al.
    Kivimäki, M.
    Ferrie, J. E.
    Westerlund, Hugo
    Stockholm University, Faculty of Social Sciences, Stress Research Institute. Karolinska Institutet, Sweden.
    Vahtera, J.
    Singh-Manoux, A.
    Melchior, M.
    Zins, M.
    Goldberg, M.
    Head, J.
    Diagnosis-specific sick leave as a long-term predictor of disability pension: a 13-year follow-up of the GAZEL cohort study2012In: Journal of Epidemiology and Community Health, ISSN 0143-005X, E-ISSN 1470-2738, Vol. 66, no 2, p. 155-159Article in journal (Refereed)
    Abstract [en]

    Background Factors that increase the risk of labour market exclusion are poorly understood. In this study, we examined the extent to which all-cause and diagnosis-specific sick leave predict subsequent disability pension (DP).

    Methods Prospective cohort study of 20 434 persons employed by the French national gas and electric company (the GAZEL study). New sick-leave spells >7 days in 1990–1992 were obtained from company records. Follow-up for DP was from 1994 to 2007.

    Results The HR, adjusted for age and occupational position, for DP was 3.5 (95% CI 2.7 to 4.5) in men and 2.6 (95% CI 1.9 to 3.5) in women with one or more sick-leave spells >7 days compared with those with no sick leave. The strongest predictor of DP was sick leave with a psychiatric diagnosis, HR 7.6 (95% CI 5.2 to 10.9) for men and 4.1 (95% CI 2.9 to 5.9) for women. Corresponding HRs for sick leave due to circulatory diagnoses in men and women were 5.6 (95% CI 3.7 to 8.6) and 3.1 (95% CI 1.8 to 5.3), for respiratory diagnoses 3.9 (95% CI 2.6 to 5.8) and 2.6 (95% CI 1.7 to 4.0), and musculoskeletal diagnoses 4.6 (95% CI 3.4 to 6.4) and 3.3 (95% CI 2.2 to 4.8), respectively.

    Conclusions Sick leave with a psychiatric diagnosis is a major risk factor for subsequent DP, especially among men. Sick leave due to musculoskeletal or circulatory disorders was also a strong predictor of DP. Diagnosis-specific sick leave should be recognised as an early risk marker for future exclusion from the labour market.

  • 2740.
    Alexandersson, Camilla
    et al.
    Stockholm University, Faculty of Social Sciences, Department of Education.
    Lundh, Johanna
    Stockholm University, Faculty of Social Sciences, Department of Education.
    ”Men jag är ju den där förlorade generationen…(skratt)” - Äldres erfarenheter och upplevelser av delaktighet, datorer och IT2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of Information and Communication Technology (ICT) is a natural part of many people's everyday life today. At the same time the risk of digital divides are highlighted by several community agencies in society. One of the risk groups mentioned here are elderly people, risking of falling behind and also to be left out the whole democratic process, because of lack of access to or knowledge of computers and the Internet. The aim of this study is to highlight elderly people's experiences of computers and IT and their participation and involvement in the IT society of today. The study is inspired by the ethnographic method and has a perspective of Social constructionism in which age can be understood as a social created category. The empirical material is based on six interviews with elderly people taking a computer course for beginners, as well as participant observations carried out during the computer course. It appears in the result, that a feeling of being forced is connected to keeping up with the technological development in our society, which can be stressful and frustrating. At the same time the informants feels that it is important to “keep up” with the society, and a curiosity is expressed towards technology. Informants learn computers in an active way. Meaningfulness in learning the computer is seen in everyday life as to maintain contact with grandchildren, search for information and to manage on your own. At the time, an underlying view of themselves and others exist, where the age is given importance in that it is harder to learn when you are old, or that older teachers are preferred since they have more understanding. In contrast to this it is expressed that good teachers will not depend on age, and those in the informants surroundings that supports them are usually young.

  • 2741.
    Alexandersson, Kristina
    et al.
    Stockholm University, Faculty of Social Sciences, School of Business.
    Meinshausen, Anne
    Stockholm University, Faculty of Social Sciences, School of Business.
    Den gode världsmedborgaren: En fallstudie av svenska IT-företags sociala ansvarstagande i Ryssland2003Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Har företag ett ansvar mot samhället? Uppsatsen tar upp den etiska frågan om företags sociala ansvar. Vid ett flertal tillfällen har den alldeles för tidigt avlidna och tidigare utrikesministern Anna Lindh uttryckt en vilja att svenska företag skall visa stor respekt för de mänskliga rättigheterna när de etablerar sig utomlands.

  • 2742.
    Alexandersson, Pelle
    Stockholm University, Faculty of Social Sciences, Department of Psychology.
    Psykometrisk prövning av PG-13; ett självskattningsinstrument för ihållande sorg2010Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Frågan om ”normal” respektive ”patologisk” sorg har under en lång tid varit ett omdiskuterat ämne inom psykologin och psykiatrin. En grupp forskare har tagit fram kriterier på ett syndrom som fått benämningen ihållande sorg (”prolonged grief”). Studier har visat på att ihållande sorg är ett distinkt syndrom separat från depression, posttraumatisk stressyndrom och generaliserat ångestsyndrom. Ihållande sorg föreslås ingå som en diagnos i de kommande versionerna av de diagnostiska manualerna DSM och ICD. Syftet med denna studie var att översätta självskattningsinstrumentet Prolonged Grief Disorder (PG-13) till svenska, och undersöka dess reliabilitet och validitet genom bland annat en explorativ och konfirmatorisk faktoranalys. Studien genomfördes på ett annonsrekryterat heterogent sample (n=162 varav 90 % var kvinnor) vad gäller typ av dödsfall och relation till den avlidne. Respondenterna besvarade en webb- eller pappersenkät som bestod av 75 items. PG-13 bedöms ha en hög reliabilitet, god begrepps- och samtidig validitet samt en måttlig diskriminativ validitet.

  • 2743.
    Alexandersson, Per
    Stockholm University, Faculty of Science, Department of Mathematics.
    Combinatorial Methods in Complex Analysis2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The theme of this thesis is combinatorics, complex analysis and algebraic geometry. The thesis consists of six articles divided into four parts.

    Part A: Spectral properties of the Schrödinger equation

    This part consists of Papers I-II, where we study a univariate Schrödinger equation with a complex polynomial potential. We prove that the set of polynomial potentials that admit solutions to the Schrödingerequation is connected, under certain boundary conditions. We also study a similar result for even polynomial potentials, where a similar result is obtained.

    Part B: Graph monomials and sums of squares

    In this part, consisting of Paper III, we study natural bases for the space of homogeneous, symmetric and translation-invariant polynomials in terms of multigraphs. We find all multigraphs with at most six edges that give rise to non-negative polynomials, and which of these that can be expressed as a sum of squares. Such polynomials appear naturally in connection to expressing certain non-negative polynomials as sums of squares.

    Part C: Eigenvalue asymptotics of banded Toeplitz matrices

    This part consists of Papers IV-V. We give a new and generalized proof of a theorem by P. Schmidt and F. Spitzer concerning asymptotics of eigenvalues of Toeplitz matrices. We also generalize the notion of eigenvalues to rectangular matrices, and partially prove the a multivariate analogue of the above.

    Part D: Stretched Schur polynomials

    This part consists of Paper VI, where we give a combinatorial proof that certain sequences of skew Schur polynomials satisfy linear recurrences with polynomial coefficients.

  • 2744.
    Alexandersson, Per
    Stockholm University, Faculty of Science, Department of Mathematics.
    On Eigenvalues of the Schrodinger Operator with an Even Complex-Valued Polynomial Potential2012In: Computational methods in Function Theory, ISSN 1617-9447, E-ISSN 2195-3724, Vol. 12, no 2, p. 465-481Article in journal (Refereed)
    Abstract [en]

    In this paper, we generalize several results in the article Analytic continuation of eigenvalues of a quartic oscillator of A. Eremenko and A. Gabrielov [4]. We consider a family of eigenvalue problems for a Schrodinger equation with even polynomial potentials of arbitrary degree d with complex coefficients, and k < (d + 2)/2 boundary conditions. We show that the spectral determinant in this case consists of two components, containing even and odd eigenvalues respectively. In the case with k = (d + 2)/2 boundary conditions, we show that the corresponding parameter space consists of infinitely many connected components.

  • 2745.
    Alexandersson, Per
    Stockholm University, Faculty of Science, Department of Mathematics.
    On eigenvalues of the Schrödinger operator with a complex-valued polynomial potential2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, we generalize a recent result of A. Eremenko and A. Gabrielov on irreducibility of the spectral discriminant for the Schroedinger equation with quartic potentials.

    In the first paper, we consider the eigenvalue problem with a complex-valued polynomial potential of arbitrary degree d and show that the spectral determinant of this problem is connected and irreducible. In other words, every eigenvalue can be reached from any other by analytic continuation. We also prove connectedness of the parameter spaces of the potentials that admit eigenfunctions satisfying k > 2 boundary conditions, except for the case d is even and k = d/2. In the latter case, connected components of the parameter space are distinguished by the number of zeros of the eigenfunctions.

    In the second paper, we only consider even polynomial potentials, and show that the spectral determinant for the eigenvalue problem consists of two irreducible components. A similar result to that of paper I is proved for k boundary conditions.

  • 2746.
    Alexandersson, Per
    Stockholm University, Faculty of Science, Department of Mathematics.
    Schur polynomials, banded Toeplitz matrices and Widom's formula2012In: The Electronic Journal of Combinatorics, ISSN 1097-1440, E-ISSN 1077-8926, Vol. 19, no 4, p. P22-Article in journal (Refereed)
    Abstract [en]

    We prove that for arbitrary partitions lambda subset of kappa, and integers 0 <= c < r <= n, the sequence of Schur polynomials S(kappa+k.1c)/(lambda+k.1r)(x(1), ... , x(n)) for k sufficiently large, satisfy a linear recurrence. The roots of the characteristic equation are given explicitly. These recurrences are also valid for certain sequences of minors of banded Toeplitz matrices. In addition, we show that Widom's determinant formula from 1958 is a special case of a well-known identity for Schur polynomials.

  • 2747.
    Alexandersson, Per
    Stockholm University, Faculty of Science, Department of Mathematics.
    Stretched skew Schur polynomials are recurrent2014In: Journal of combinatorial theory. Series A (Print), ISSN 0097-3165, E-ISSN 1096-0899, Vol. 122, p. 1-8Article in journal (Refereed)
    Abstract [en]

    We show that sequences of skew Schur polynomials obtained from stretched semi-standard Young tableauxsatisfy a linear recurrence, which we give explicitly.Using this, we apply this to finding certain asymptotic behavior of these Schur polynomials and present conjectures on minimal recurrences for stretched Schur polynomials.

  • 2748.
    Alexandersson, Per
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics.
    Gabrielov, Andrei
    On Eigenvalues of the Schrödinger Operator with a Complex-Valued Polynomial Potential2012In: Computational methods in Function Theory, ISSN 1617-9447, E-ISSN 2195-3724, Vol. 12, no 1, p. 119-144Article in journal (Refereed)
    Abstract [en]

    We consider the eigenvalue problem with a complex-valued polynomial potential of arbitrary degree d and show that the spectral determinant of this problem is connected and irreducible. In other words, every eigenvalue can be reached from any other by analytic continuation.

    We also prove connectedness of the parameter spaces of the potentials that admit eigenfunctions satisfying k > 2 boundary conditions, except for the case d is even and k = d/2. In the latter case, connected components of the parameter space are distinguished by the number of zeros of the eigenfunctions.

    The first results can be derived from H. Habsch, while the case of a disconnected parameter space is new.

  • 2749.
    Alexandersson, Per
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics.
    Shapiro, Boris
    Stockholm University, Faculty of Science, Department of Mathematics.
    Around multivariate Schmidt-Spitzer theorem2014In: Linear Algebra and its Applications, ISSN 0024-3795, E-ISSN 1873-1856, Vol. 446, p. 356-368Article in journal (Refereed)
    Abstract [en]

    Given an arbitrary complex-valued infinite matrix $\infmatA=(a_{ij}),$$i=1,\dotsc,\infty;$ $j=1,\dotsc,\infty$  and a positive integer $n$ we introduce anaturally associated  polynomial basis $\polybasis_\infmatA$ of$\C[x_0,\dotsc,x_n]$.We discuss some properties of the locus of  common zeros of all polynomials in $\polybasis_A$ having  a given degree $m$; the latter locus can beinterpreted as the spectrum of the $m\times (m+n)$-submatrix of $\infmatA$ formed by its  $m$ first rows and$(m+n)$ first columns. We initiate the study of the asymptotics of these spectra when $m\to \infty$ inthe case when $\infmatA$ is a banded Toeplitz matrix.In particular, we present and partially prove a conjectural multivariate analogof the well-known Schmidt-Spitzer theorem which describes  the spectral asymptotics for the sequence of principal minors of an arbitrarybanded Toeplitz matrix.Finally, we discuss relations between polynomial bases $\polybasis_\infmatA$ andmultivariate  orthogonal polynomials.

  • 2750.
    Alexandersson, Per
    et al.
    Stockholm University, Faculty of Science, Department of Mathematics.
    Shapiro, Boris
    Stockholm University, Faculty of Science, Department of Mathematics.
    Discriminants, Symmetrized Graph monomials and Sums of Squares2012In: Experimental Mathematics, ISSN 1058-6458, E-ISSN 1944-950X, Vol. 21, no 4, p. 353-361Article in journal (Refereed)
    Abstract [en]

    In 1878, motivated by the requirements of the invariant the-ory of binary forms, J. J. Sylvester constructed, for every graphwith possible multiple edges but without loops, its symmetrizedgraph monomial, which is a polynomial in the vertex labels ofthe original graph. We pose the question for which graphs thispolynomial is nonnegative or a sum of squares. This problem ismotivated by a recent conjecture of F. Sottile and E. Mukhin onthe discriminant of the derivative of a univariate polynomial andby an interesting example of P. and A. Lax of a graph with fouredges whose symmetrized graph monomial is nonnegative butnot a sum of squares. We present detailed information about sym-metrized graph monomials for graphs with four and six edges,obtained by computer calculations.

52535455565758 2701 - 2750 of 104663
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