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  • Disputas: 2018-04-05 10:00 Vivi Täckholmssalen (Q-salen), NPQ-huset, Stockholm
    Losvik, Aleksandra
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och botanik.
    Barley defense genes against aphids2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Aphids are insect pests with major importance worldwide. By feeding from plant phloem, they directly withdraw nutrients. The feeding injury is often visible in the form of leaf rolling, chlorosis, necrosis or plant deformation. Their pest status is attributed also to vectoring of plant viruses. Aphid infestation on crop plants is currently managed with the use of pesticides, which may pose a threat to the environment. An alternative approach would be to identify and characterize genetic factors contributing to aphid resistance, as well as agents inducing resistance, with the intention to use this knowledge in breeding programs.

    The aim of this thesis was to identify such resistance genes and characterize their involvement in plant-aphid interactions. This was accomplished using two approaches. Firstly, two putative aphid-resistance genes from barley, CI2c encoding a chymotrypsin inhibitor and LOX2.2 encoding a lipoxygenase, were transformed into Arabidopsis and/or barley and the effects of transformation were studied with regard to the performance of two aphid species. One was the specialist bird cherry-oat aphid (Rhopalosiphum padi L.), which is a pest on major cereals, and the other was a generalist, the green peach aphid (Myzus persicae Sulzer), which is a pest on plants belonging to more than 40 families. The effects of transformation were also studied concerning effects on the expression of other defense-related genes in the transgenic plants. Secondly, the effects of plant treatment with volatiles were studied with regard to induction of plant resistance, followed by tests with bird cherry-oat aphid on the treated plants.

    The study of overexpression of CI2c showed that the gene product transiently reduced green peach aphid fecundity on transgenic Arabidopsis, but indirectly decreased this aphid’s avoidance of barley by suppressing defense. The transformation had no effects on bird cherry-oat aphids’ behaviour or fecundity. Overexpression of LOX2.2 was shown to affect expression of other genes regulated by jasmonic acid and decreased the short-term fecundity of both the bird cherry-oat aphid and the green peach aphid on barley. The study of volatile treatments supported the idea that resistance against aphids can be induced by application of volatiles. Several defense gene sequences were induced by application of methyl salicylate, methyl jasmonate and (Z)-3-hexen-1-ol. Of the three volatiles tested, methyl jasmonate showed the greatest potential as inducing agent, causing a short-term reduction in aphid fecundity.

    To conclude, this thesis supports the ideas that the barley genes CI2c and LOX2.2 play a role in resistance against aphids and that moderate aphid resistance can be induced by external factors. Aphids may be directly affected by the gene product or there may be an indirect effect, caused by changes in the expression of other genes involved in plant defense. The observed negative effects on aphids were of moderate magnitude and it is proposed that acting individually, those genes are not likely to cause a strong negative effect, but they may contribute to provide resistance to aphids.

  • Disputas: 2018-04-06 10:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Pathi Pati, Stalin Reddy
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Development of new Catalytic Methods for the Selective Synthesis of Heterocycles2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In the field of organic chemistry, the development of new catalytic methods for the synthesis of complex molecules from simple precursors is a top priority. The main focus of this thesis concerns the diastereoselective synthesis of heterocyclic compounds using main group elements as Lewis acid catalysts.

    The first part of this thesis deals with an annulation reaction of nitrones with oxiranes, aziridines, and thiiranes using Al(III) or In(III) catalysts. From this protocol, 1,4,2-dioxazinanes, 1,2,4-oxadiazinanes, and 1,4,2-oxathiazinanes were obtained in moderate to high yields with excellent diastereoselectivity. The transformation was found to be stereospecific and proceed via an SN2-mechanism.

    The second and third parts concern the development of In(III)-catalyzed annulation of carbonyl compounds, amines, and alkynyl enones. InBr3 was found to be an efficient catalyst for the activation of alkynyl enones in a multicomponent reaction with aldehydes and amines. The method affords cyclopenta[c]furans in high yields and in good to excellent diastereomeric ratios. Bicyclo[3.n.1]alkenone derivatives were formed via a double Michael addition reaction of cyclic ketones, amines, and alkynyl enones, in the presence of InCl3. The utility of these protocols was also demonstrated by sequential transformations.

    In the fourth part, AgOTf and CuI were found to be efficient catalysts for the activation of pyridine-substituted enynes towards enamines, providing indolizine derivatives in high yield and good diastereomeric ratios.

    In the last part of the thesis, 1,2-aminoarylation of γ,δ-unsaturated oxime esters with arylboronic acids using Ni catalysis is discussed. The protocol demonstrates the potential of Ni-catalysts for the generation of iminyl radicals to furnish functionalized pyrroline derivatives. The utility of this protocol was exemplified by transforming the pyrroline products to the corresponding pyrrole and pyrrolidine derivatives. 

  • Disputas: 2018-04-06 13:00 De Geersalen, Geovetenskapens hus, Stockholm
    Holmberg, Linnéa
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Barn- och ungdomsvetenskapliga institutionen.
    Konsten att producera lärande demokrater2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This dissertation builds on the basic question of how individuals are formed and created as citizens in society today, and how individuals construct themselves as citizens in this society. It takes interest in how they are managed to govern themselves through specific constructions of citizenship, and looks at how the exercise of power establishes certain knowledge that affects their view of themselves and generates truths about how they are expected to live their lives. Simultaneously, the dissertation deals with the concept of freedom: what does it mean in contemporary society, how can one be free today, and what dangers might this liberty involve?

    In a broad sense, the analysis centres on the relationship between education and society; more specifically, it engages with the Swedish education system and its construction and production of desirable citizen subjects. The concrete example deals with the institution called leisure-time centre, with a purpose to investigate and problematise how institutionalised leisure-time is staged and legitimised in Sweden today. The studies take as a common starting point the following research question: how are children and personnel governed discursively in and through leisure-time centres?

    The first empirical contribution provides historical context for the study. In this, the `problematic leisure-time´ of today is outlined based on education policy documents relevant for children aged 6–13 years. These texts are discussed together with similar texts gathered from two other periods in history in order to give perspective on aspects of the leisure-time centre that may seem obvious in our own time.

    The first separate article investigates how talk about activities in leisure-time centres is couched in terms of meaningfulness and consists of an analysis of the ideological tension between democracy and authority, which the governmental authority, the Swedish Schools Inspectorate (Skolinspektionen), must address in its discursive work. 

    The second article explores how the production of systematic reporting and documentation by personnel in leisure-time centres works through specific self-technologies in the form of confessional practices and which can be said to be primarily about constructing a free but loyal collective subject.

    The third article problematises the use of democracy as a method to produce specific citizen subjects in leisure-time centres. Children’s councils are analysed, focusing on how different nuances of influence are staged discursively by participating children and personnel. The article highlights how democracy – through pastoral care and in the name of children’s influence – becomes a governmentalising technology that produces an active, responsible and learning citizen.

    In summary, this dissertation highlights how leisure-time centres are staged and legitimised in Sweden today. The analysis shows how an administration of children and control of the development of society through the autonomous, competent, and voluntarily active individual is apparent; power operates through a perceived freedom in a way that makes the free choice the `right´ choice. With political ideas about forming a forward-looking mentality, children – and personnel – are constructed as a project of learning and improvement.

  • Disputas: 2018-04-13 10:00 Aula Svea, Socialhögskolan, Stockholm
    Storm, Palle
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för socialt arbete - Socialhögskolan.
    Betydelsen av kön och hudfärg i äldreboendets vardag under olika organisatoriska villkor2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Even though nursing home care in Sweden and Canada takes place in different care contexts and utilizes different organisational models, in both countries, the traditional image of an ideal care worker is characterized by femininity and whiteness. However, today, in both countries, the care workforce is becoming far more diverse, with increasing numbers of white men, and non-white women and men.

    The overarching aim of this thesis is to study the meaning of gender and skin colour in the everyday life in Swedish and Canadian nursing homes. The study, based on observations and interviews, focuses on how organizational conditions contribute to creating, maintaining and challenging notions of gender and skin colour.

    The thesis consists of four articles, analysing the following questions:

    How is gender, in interaction with ethnicity and sexuality, expressed by women and men care workers in a Swedish nursing home? How do organizational conditions shape and influence men’s positions and their possibilities to be integrated and accepted as care workers in two Canadian nursing homes characterized by different care models?  How do organizational conditions impact on care workers’ strategies to handle skin colour, racism and language problems in Swedish and Canadian nursing homes characterized by different scope for care workers to exercise discretion? How do non-white men born outside Europe describe their experiences of working in Swedish nursing homes, and what does it mean for them to have a body that differs from the traditional image of a care worker?

    Overall, the findings demonstrate that an interaction of gender and skin colour shapes the workers’ experiences and position in the everyday life of care. The most profound impact is on those who deviate the most from the normative care worker, non-white men care workers. Significantly, the results also show that the ability for the organization to handle diversity is highly dependent on whether or not the workers are able to exercise discretion in their daily work. If these organizational conditions do not exist, there is a high risk that men and non-white workers will be seen as problematic by both co-workers and residents.

    In order to mitigate these risks and manage the increasing diversity of those working in nursing homes, it is essential to recognize the importance of organizational conditions that can create and ensure acceptance and integration of care workers from diverse backgrounds. Therefore, questions about gender and skin colour must be recognized as a priority for management, an organizational matter that should not be left to the individual or the work group to handle.

  • Disputas: 2018-04-13 10:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Hallgren, Eva
    Stockholms universitet, Humanistiska fakulteten, Institutionen för de humanistiska och samhällsvetenskapliga ämnenas didaktik. Högskolan i Gävle, Avdelningen för utbildningsvetenskap.
    Ledtrådar till estetiskt engagemang i processdrama: Samspel i roll i en fiktiv verksamhet2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The aim of the thesis is to deepen the understanding of role taking and the function of role for developing and exploring the possible content in process drama, with the help of Leontiev’s activity theory and Bakhtin’s dialogism. The relation between role taking, aesthetic engagement and the concept of perezhivanie, used by Vygotsky, is also reflected on and used as analytical tools. A starting point for the study was Bundy’s concept of aesthetic engagement.

    Previous research about process drama has focused on three main themes: teaching and learning a subject matter, engagement, and creative leadership. The purpose of this study is to contribute to the knowledge base on how role is created and maintained in process drama, thereby making it possible to develop and explore a thematic content.

    One single process drama conducted at an English secondary school is closely analysed in the thesis. A whole day session was filmed, transcribed and interpreted into thick descriptions. Interviews and letters written in role are used as complementary data. This made it possible to focus on nuances and subtle changes in the complexity that characterizes a process drama, and to focus on how the students’ role taking starts and develops.  

    The results from the detailed analysis showed, from an activity theory perspective, that process drama can be understood as two activities with two different motives/objects. These two are an educational activity with learning drama as motive/object and a temporary fictional activity where the motive/object is tentative and under construction through the pupils’ in-role-actions. Actions deriving from the educational activity should not be allowed to influence the fictional, otherwise the fictional activity will be diminished.

    How the teacher used power levelling postupaks, when opening dilemmas, and teacher-in-role was of great importance for the pupils’ role taking. Postupaks are a consequence of the format of the temporary fictional activity and the interpretation of the tentative motive/object. Using postupaks in role develops what I call expectagency, a capacity based on mutual agreement in an activity with a playful format, where the negotiations become qualitatively different when done by postupaks. Expectagency is a capability to handle uncertainty and change. The use of postupaks was crucial for both the maintenance of the fiction and the exploration of the thematic content. Going into and being in role is a complex process. Six kinds of postupaks were discerned, aimed at developing and exploring, and six other kinds of postupaks served to re-charge the tension by using aesthetic tools. Another important finding was how the students re-used postures and gestures from an initial freeze frame as tools for role taking during the whole drama, and especially when the tension decreased.   

    The fictional activity is turbo-charged, generating feelings both in and out of role, charged through different kinds of tension; between the two activities, oneself and the role (aesthetic doubling), the use of postupaks and the dramatic tension. This turbo-charged activity is a short cut for perezhivanie. Perezhivanie is tangential to the concept of aesthetic engagement, but from an educational perspective the expanded concept of aesthetic engagement appears to be more useful.

  • Disputas: 2018-04-13 13:00 hörsal 7, hus D, Stockholm
    Hallonsten Halling, Pernilla
    Stockholms universitet, Humanistiska fakulteten, Institutionen för lingvistik.
    Adverbs: A typological study of a disputed category2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The notion adverb is often treated as encompassing leftover items in a class that shows little consistency both within and ​across languages. Adverbs are less frequent than other parts of speech cross-linguistically, they seldom inflect, and they are rarely used as a source for derivation to other categories.

    This dissertation focuses on adverbs that denote properties and that can be used as modifiers within predicating expressions. The adverbs in this group are roughly equivalent to the traditional manner adverbs (She walked slowly). In their role as modifiers, these adverbs are parallel to attributive adjectives, which also denote properties, and are modifiers in referring expressions (slow train). Adjectives often also occur in the predicative function (The train is slow). This study compares adverbs to attributive and predicative adjectives in a sample of 60 genealogically diverse languages from around the world. Simple adverbs are attested in the majority of these languages, including in some languages that do not have simple adjectives. The comparison with attributive and predicative adjectives is carried out at three levels of encoding: the root, the lexeme, and the construction. The analysis shows that a great majority of languages have the same root encoding for adverbs, attributive adjectives, and predicative adjectives. Many languages have a class of lexemes that are used in the functions of both adverbs and attributive adjectives, here called general modifiers. On the construction level, where constructions are analyzed in their entirety, important encoding similarities between adverbs and predicative adjectives are unraveled. In a few languages, adverbs and attributive adjectives are encoded by the same or similar constructions.

    The attested simple adverbs and general modifiers both fall into certain characteristic semantic types. For simple adverbs, a core type is SPEED, which is found among the adverbs of most sample languages. The types VALUE, CARE, and NOISE are also found among the simple adverbs of several languages. For general modifiers, VALUE appears as a core type. These semantic types are further attested in tendencies of adverb lexicalization and in adverbial affixation across languages. 

    This dissertation shows that adverbs constitute a cross-linguistically prototypical part of speech, although they differ in many ways from other categories. The basis for this class, just as for adjectives, is the presence of simple lexemes that tend to have similar semantics in unrelated and geographically distant languages. Adverbs are thus conceptually no less basic than adjectives.