Crystallization on the Mesoscale : Self-Assembly of Iron Oxide Nanocubes into Mesocrystals

Self-assembly of nanoparticles is a promising route to form complex, nanostructured materials with functional properties. Nanoparticle assemblies characterized by a crystallographic alignment of the nanoparticles on the atomic scale, i.e. mesocrystals, are commonly found in nature with outstanding functional and mechanical properties. This thesis aims to investigate and understand the formation mechanisms of mesocrystals formed by self-assembling iron oxide nanocubes. We have used the thermal decomposition method to synthesize monodisperse, oleate-capped iron oxide nanocubes with average edge lengths between 7 nm and 12 nm and studied the evaporation-induced self-assembly in dilute toluene-based nanocube dispersions. The influence of packing constraints on the alignment of the nanocubes in nanofluidic containers has been investigated with small and wide angle X-ray scattering (SAXS and WAXS, respectively). We found that the nanocubes preferentially orient one of their {100} faces with the confining channel wall and display mesocrystalline alignment irrespective of the channel widths.  We manipulated the solvent evaporation rate of drop-cast dispersions on fluorosilane-functionalized silica substrates in a custom-designed cell. The growth stages of the assembly process were investigated using light microscopy and quartz crystal microbalance with dissipation monitoring (QCM-D). We found that particle transport phenomena, e.g. the coffee ring effect and Marangoni flow, result in complex-shaped arrays near the three-phase contact line of a drying colloidal drop when the nitrogen flow rate is high. Diffusion-driven nanoparticle assembly into large mesocrystals with a well-defined morphology dominates at much lower nitrogen flow rates. Analysis of the time-resolved video microscopy data was used to quantify the mesocrystal growth and establish a particle diffusion-based, three-dimensional growth model. The dissipation obtained from the QCM-D signal reached its maximum value when the microscopy-observed lateral growth of the mesocrystals ceased, which we address to the fluid-like behavior of the mesocrystals and their weak binding to the substrate. Analysis of electron microscopy images and diffraction patterns showed that the formed arrays display significant nanoparticle ordering, regardless of the distinctive formation process.  We followed the two-stage formation mechanism of mesocrystals in levitating colloidal drops with real-time SAXS. Modelling of the SAXS data with the square-well potential together with calculations of van der Waals interactions suggests that the nanocubes initially form disordered clusters, which quickly transform into an ordered phase.

Exercising the self : On the Role of Exercise, Gender and Culture in Physical Self-Perceptions

In modern society, individuals constantly pass judgments on their own body and physical competence as well as that of other people. All too often, the verdict is less favourable. For the person, these physical self-perceptions (PSP) may negatively affect global self-esteem, identity, and general mental well being. The overall aim of this thesis is to examine primarily the role that exercise, but also the roles that gender and culture, play in the formation of PSP. In Study I, using confirmatory factor analyses, strong support for the validity of a first-order, and a second-order hierarchical and multidimensional model of the Physical Self-Perception Profile (PSPP: Fox & Corbin, 1989) was found across three national samples (Great Britain, Sweden and Turkey) of university students. Cross-cultural differences were detected, with the British sample demonstrating higher latent means on all PSPP subdomains except for the physical condition subdomain (Condition), than the Swedish and Turkish samples. In Study II, a higher self-reported exercise frequency was associated with more positive PSP (in particular for Condition) and more importance attributed to PSP in Swedish university students. Males demonstrated higher overall PSPP-scores than females. In Study III, a true-experimental design with randomisation into an intervention and a control group was adopted. Strong support for the effects of an empowerment-based exercise intervention programme on PSP and social physique anxiety (SPA) over six months for adolescent girls was found. The relations of exercise, gender and culture with PSP, SPA and self-esteem are discussed from the standpoints of a variety of theoretical models (the EXSEM-model), and frameworks (self-presentation and objectification theory). The two theories of self-enhancement and skill-development are examined with regard to the direction of the exercise-physical self relationship and motivation for exercise. Arguments for the relevance of exercise and PSP for practitioners in promoting general mental well-being and preventing modern-day diseases are outlined.

The Role of Luxury Fashion Brands : A qualitative research of how the consumption of luxury fashion brands relate to young consumers' self-concept

The market for luxury brands has outpaced other consumption categories through its growth, and has been found in continuous development. As there is an increasing amount of luxury categories, the consumption of luxury fashion brands account for the largest proportion of luxury profits, and the marketing costs for such brands has shown to surpass those of other fashion categories. Consumer researchers have throughout decades emphasized how individuals participate in consumption behavior to form their self-concept in relation to brands. However, previous research has disregarded the multidimensional perspective regarding the theory of self-concept when examining the consumption of brands. Hence, the current research paper aims to strengthen the existing self-concept theory by exploring the role in which luxury fashion brands have by focusing on how the consumption of such brands relate, and contribute, to the consumer’s self-concept. By applying a qualitative method to investigate such purpose, and involving the existing theory of self-concept, brand image, and brand personality, it appeared that luxury fashion brands has a function to operate as a confidence booster for young consumers’ perception of their self-concept. In terms of the theoretical contribution of this paper, this research further illustrates how the theoretical explanation of brand image and brand personality relates to two different dimensions of the consumer’s self-concept. The consumption of luxury fashion brands has shown a significant role in individuals’ consumption behavior by emphasizing a striving, and motivating, part in the self-concept of young consumers.

Women's subjective and objective health over time : the role of psychosocial conditions and physiological stress responses

Today, health problems are likely to have a complex and multifactorial etiology, whereby psychosocial factors interact with behaviour and bodily responses. Women generally report more health problems than men. The present thesis concerns the development of women’s health from a subjective and objective perspective, as related to psychosocial living conditions and physiological stress responses. Both cross-sectional and longitudinal studies were carried out on a representative sample of women. Data analysis was based on a holistic person-oriented approach as well as a variable approach. In Study I, the women’s self-reported symptoms and diseases as well as self-rated general health status were compared to physician-rated health problems and ratings of the general health of the women, based on medical examinations. The findings showed that physicians rated twice as many women as having poor health compared to the ratings of the women themselves. Moreover, the symptom ”a sense of powerlessness” had the highest predictive power for self-rated general health. Study II investigated individual and structural stability in symptom profiles between adolescence and middle-age as related to pubertal timing. There was individual stability in symptom reporting for nearly thirty years, although the effect of pubertal timing on symptom reporting did not extend into middle-age. Study III explored the longitudinal and current influence of socioeconomic and psychosocial factors on women’s self-reported health. Contemporary factors such as job strain, low income, financial worries, and double exposure in terms of high job strain and heavy domestic responsibilities increased the risk for poor self-reported health in middle-aged women. In Study IV, the association between self-reported symptoms and physiological stress responses was investigated. Results revealed that higher levels of medically unexplained symptoms were related to higher levels of cortisol, cholesterol, and heart rate. The empirical findings are discussed in relation to existing models of stress and health, such as the demand-control model, the allostatic load model, the biopsychosocial model, and the multiple role hypothesis. It was concluded that women’s health problems could be reduced if their overall life circumstances were improved. The practical implications of this might include a redesign of the labour market giving women more influence and control over their lives, both at and away from work.

Illuminating Inner Life : A Comparison of Virginia Woolf's To the Lighthouse and Arthur Schnitzler's Fräulein Else

In the early 20th century, authors increasingly experimented with literary techniques striving towards two common aims: to illumine the inner life of their protagonists and to diverge from conventional forms of literary representations of reality. This shared endeavour was sparked by changes in society: industrialisation, developments in psychology, and the gradual decay of empires, such as the Victorian (1837–1901) and the Austro-Hungarian (1867–1918). Those developments yielded a sense of uncertainty and disorientation, which led to a so-called “turn [inwards]” in the arts (Micale 2). In this context, this essay examines Virginia Woolf’s (1882–1941) development of her literary technique by comparing To the Lighthouse (1927), written in free indirect discourse, with Arthur Schnitzler’s (1862–1932) Fräulein Else (1924), written in interior monologue. Instead of applying Freud’s theories of consciousness, I will demonstrate how empiricist psychology informed and partly helped shape the two narrative techniques by referring to Ernst Mach’s (1838–1916) idea of the unstable self, and William James’ (1842–1910) concept of the stream of consciousness. Furthermore, I will show that there is a continuous progression of literary ideas from Schnitzler’s Viennese fin-de-siècle connected to impressionism, towards Woolf’s Bloomsbury aesthetics connected to Paul Cézanne’s post-impressionist logic of sensations. In addition to that, I address how the women’s movement, starting in the end of the 19th century, inspired Woolf and Schnitzler to utilise their techniques as a means of revealing women’s restricted position in society. Methodologically, I will analyse the two novels’ narrative techniques applying close reading and by that point out their differences and similarities in connection to the above-mentioned theories as well as the two author’s literary approaches. I argue that this comparison demonstrates that modernist literary techniques of representing interiority evolved from interior monologue towards free indirect discourse. This progression also implicates that modernism can be seen as a continuum reaching back to the fin-de-siècle and culminating in the 1920s. 

Muslim Women Managing Women's Shelters : Somaya, the Muslimwoman and Religion as Resource

This article focuses on Sisters’ Shelter Somaya in Sweden, an organization unique in its claim to be a women’s shelter by and for Muslim women, and in its combining of Islamic and secular feminisms. Examining the organization’s self-presentations, the author argues that there is, however, an ongoing shift from an emphasis on its Muslim profile to a dissolution of the very same. Looking into potential loss in the process (for clients, activists, allies, and feminism at large), the analysis draws on current research on anti-Muslim intolerance and normative secularism. The concept of the “Muslim woman” is employed to illustrate the stereotyping that continuously associates Muslim women with “victims” inhabiting shelters rather than capable “managers”. Intersectionality is pointed at as an emic strategy adopted by Somaya to overcome division, but also critically analysed as a consensus-creating signifier that hinders diversity. Thus,the article raises the increasingly important issue of the relationship between religion, gender, and feminism in the post-secular turn, and the author calls for critical self-reflection and creative affirmation in the interaction with heterogeneous others.