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Den mänskliga populationen har tredubblats på 70 år och det råder konsensus om att människan är den dominerande faktorn till klimatförändringarna och den negativa påverkan på ekosystemens processer. Det betonar att den globala utvecklingen främst vilar i mänsklighetens händer, inte minst den urbana utvecklingen då städer i hög grad driver på klimatpåverkan. Därför behövs social-ekologiska hållbara system i städerna utvecklas för att bidra till global hållbarhet och för att främja människors välbefinnande. I städer är grönområden viktiga för människors välbefinnande och gynnar även den ekologiska anknytningen som är betydande för miljöfrämjande värderingar vilket understryker vikten av invånares integreringsmöjligheter med grönområden. Studier pekar däremot på att upplevd otrygghet kan hindra integreringen med grönområden och att kvinnor i högre utsträckning upplever barriärer än män. Samuelsson, Peterson, Legeby, Brandt, & Barthel (2018) studie syftade till att undersöka människors upplever i Stockholm ur ett miljöpsykologiskt perspektiv. Med den studien som utgångspunkt syftar detta examensarbete till fördjupad förståelse för hur den urbana miljön påverkar registrerade upplevelser baserat på upplevd trygghet och även ur ett könsperspektiv. Samuelsson et al. (2018) utgick från en upplevelse- och deltagande baserad metodik för att förena rumsliga och erfarenhetsmässiga aspekter. I detta examensarbete utfördes därmed två statistiska kvantitativa analyser där den första syftade till att studera samband mellan upplevelser baserat på upplevd trygghet och miljökvalitet. Resultatet visade att positiva trygga upplevelser registrerats främst i grönområden och negativa otrygga i byggd stadsmiljö. Baserat på så få negativa registrerade upplevelser i grönområden syftade den andra analysen till att enbart analysera skillnaden mellan kön och positivt registrerade upplevelser i grönområden och i byggd stadsmiljö. Resultatet visade att kvinnor skattar både byggd stadsmiljö och grönområden i högre grad än män. Resultatet visade även att grönområden i högre grad skattats som positiva än byggd stadsmiljö. Det fanns ingen interaktionseffekt mellan kön och miljökvalitet, men en tendens till ett signifikant resultat. Utifrån behovet att utveckla hållbara social-ekologiska system i städer för att främja global hållbarhet finns även ett behov att studera människors upplevelser i den urbana miljön. Utifrån resultaten i examensarbetet dras slutsatsen om att åtgärder i stadsutvecklingsprocessen främst bör riktas att designa den byggda stadsmiljön för att främja människors välbefinnande och att grönområden ska bibehållas och stärkas. Studier har visat på att kvinnor i högre utsträckning upplever barriärer för att interagera med grönområden men detta resultat visade inga belägg för det utan tvärtom att kvinnor skattar upplevelser i grönområden högre än män. Därmed anses det vara intressant att i framtida studier studera andra individuella skillnader som kan påverka upplevelserna, exempelvis fysiska och psykiska barriärer. Det vore även intressant att vidare studerar hur element i den urbana miljön, som belysning och bullernivåer, påverkar människors upplevelser och upplevda trygghet. Dessutom bidrar det här examensarbetet med betydande förbättringsförslag till hur framtida PPGIS-undersökningar kan utformas för att förbättra analysmöjligheterna. The human population has tripled in 70 years and there is a consensus that humankind is the dominant factor in climate change and that ecosystem processes are adversely affected. It emphasizes that global development is primarily in the hands of humanity and, not least, the urban development as cities are greatly driving climate change. This requires sustainable urban systems to contribute to global sustainability and to promote people's well-being. In cities, green spaces are particularly important for people's well-being and also promote the ecological connection that is important for environmental-promoting values. It underlines the importance of residents' integration opportunities with green spaces. Studies, on the other hand, suggest that perception of unsafety can hinder integration with green spaces and that women experience barriers to a greater extent than men. Samuelsson, Peterson, Legeby, Brandt, & Barthel (2018) study aimed to investigate people's experiences in Stockholm from an environmental-psychology perspective. Based on this study, this thesis aims at a deeper understanding of how the urban environment affects experiences based on perceived safety and from a gender perspective. Samuelsson et al. (2018) study was based on an experience- and participation-based approach to combining spatial and experiential aspects. In this work, two quantitative statistical analyses were carried out in which the first analysis was aimed to study whether there were links between experiences, based on perceived safety, and environmental quality. The result showed that positive safe experiences were recorded mainly in green areas and negative unsafe in built urban environments. Based on a small percentage of negative experiences in green areas the second analysis aimed to analyze only the difference between gender and positively recorded experiences in green areas and in built urban environments. The results showed that women estimating both built urban environment and green spaces in a higher grade than men based on perceived safety. The results also showed that green spaces were more appreciated as positive experiences than built urban environments. There was no statistical interaction between gender and environmental quality, but a tendency of a significant result. Based on the necessity to develop sustainable social-ecological systems in cities to promote global sustainability, there is also a need to study people's experiences in the urban environment. Based on the results of this thesis, it is concluded that actions in the urban development process should primarily focus on designing the built urban environment in order to promote people's well-being and green spaces should primarily be maintained and strengthened. Studies have shown that women in a greater extent experience barrier to integrate with green spaces, but this thesis showed no evidence of this, instead women rate experiences in green spaces higher than men. Therefore, it is considered interesting to study individual differences that can affect experiences instead, such as physical and mental barriers. It would also be interesting if future studies aimed to study how elements of the urban environment, such as lighting and noise levels, affect people's experiences and perceived safety. In addition, this thesis contributes significant improvement proposals to how future PPGIS surveys can be designed to improve analysis opportunities.

Nickel (Ni) compounds are classified as carcinogenic to humans but the underlying mechanisms are still poorly understood. Furthermore, effects related to nanoparticles (NPs) of Ni have not been fully elucidated. The aim of this study was to investigate genotoxicity and mutagenicity of Ni and NiO NPs and compare the effect to soluble Ni from NiCl2. We employed different models; i.e., exposure of (1) human bronchial epithelial cells (HBEC) followed by DNA strand break analysis (comet assay and γ‐H2AX staining); (2) six different mouse embryonic stem (mES) reporter cell lines (ToxTracker) that are constructed to exhibit fluorescence upon the induction of various pathways of relevance for (geno)toxicity and cancer; and (3) mES cells followed by mutagenicity testing (Hprt assay). The results showed increased DNA strand breaks (comet assay) for the NiO NPs and at higher doses also for the Ni NPs whereas no effects were observed for Ni ions/complexes from NiCl2. By employing the reporter cell lines, oxidative stress was observed as the main toxic mechanism and protein unfolding occurred at cytotoxic doses for all three Ni‐containing materials. Oxidative stress was also detected in the HBEC cells following NP‐exposure. None of these materials induced the reporter related to direct DNA damage and stalled replication forks. A small but statistically significant increase in Hprt mutations was observed for NiO but only at one dose. We conclude that Ni and NiO NPs show more pronounced (geno)toxic effects compared to Ni ions/complexes, indicating more serious health concerns. Environ. Mol. Mutagen. 59:211–222, 2018. © 2017 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society

Table S1. Chromatid- and chromosome-type aberrations and mitotic index. Figure S1. Apoptotic and Necrotic indices by CBMN Cyt assay. Figure S2. Representative metaphases of BEAS-2B cells (DOCX 267 kb).

The structural behavior in aqueous mixtures of negatively charged silver nanoparticles (Ag NPs) together with the cationic surfactants cetyltrimethylammonium bromide (CTAB) and dodecyltrimethylammonium chloride (DTAC), respectively, has been investigated using SANS and SAXS. From our SANS data analysis we are able to conclude that the surfactants self-assemble into micellar clusters surrounding the Ag NPs. We are able to quantify our results by means of fitting experimental SANS data with a model based on cluster formation of micelles with very good agreement. Based on our experimental results, we propose a novel mechanism for the stabilization of negatively charged Ag NPs in a solution of positively charged surfactants in which cluster formation of micelles in the vicinity of the particles prevents the particles from aggregating. Complementary SAXS and DLS measurements further support this novel way of explaining stabilization of small hydrophilic nanoparticles in surfactant-containing solutions.

Metallic nanoparticles possess unique properties due to their size and are widely used in e.g. consumer products. From this follows a need to identify and assess potential risks of human and environmental exposure. Their size facilitates uptake in organisms and disruption of various biological processes. Together with a high reactivity, mainly due to their large surface area in solution, they are both commonly used in different applications and of a potential safety concern. Risk assessment requires hence in-depth knowledge on the particle characteristics and their behavior in solution but also how these properties change with time and exposure conditions and whether these characteristics can be linked to toxicity following nanoparticle exposure. This thesis addresses these aspects with a main focus on metal nanoparticles and elaborates on the importance of characterization, how such measurements can be done, and on interactions with surfactants and biomolecules and toxic effects.Silver nanoparticles are, due to their antibacterial properties, often used in sportswear to prevent sweat odor. During laundry they may be dispersed and interact with surfactants of the washing powder, influencing their properties and stability in solution. These aspects are addressed in Papers I, III and V on silver nanoparticles of different size and surface coatings. The stability was shown to depend on the surface charge and the concentration of the surfactant. The stability and extent of silver release were reduced upon sequential exposure, indicating the importance of the particle history on their bioaccessibility, mobility and potential toxicity. A mechanism was proposed for how silver nanoparticles are stabilized in surfactant solutions.Toxic effects of silver nanoparticles of different size and coatings on cultivated lung cells, Paper II, and effects of copper-containing nanoparticles on different blood cells, Paper IV, were studied in vitro. The smallest particles were most cytotoxic and the “Trojan horse” mechanism played an important role, meaning that the nanoparticles facilitate cellular uptake followed by ion-release.Difficulties in the determination and interpretation of the zeta potential, related to the surface charge, of metal nanoparticles in complex solutions are elucidated in Paper VI. Guidelines are provided on how to accurately assess this property. QC 20170111

Title: Understanding resistance to organizational change: a cognitive approach Authors: Emmy Morehed & Sara Skoglund Level: Degree thesis, 30 hp Keywords: Organizational change, Resistance to change, Cognitive perception Background: Organizational change is a naturally occurring phenomenon and is vital for the survival of organizations. However, the majority of organizational change initiatives result in failure. Resistance to change has been found to be the key reason for this organizational change failure. It is therefore important for change agents to understand and manage the change recipients’ resistance to change, in order to achieve organizational change success. Research question: What role does the change recipients’ cognitive perception of organizational change have, when assessing their resistance to change? Purpose: The purpose of this study is to develop our understanding of the change recipients’ resistance to organizational change, as it is cognitively perceived, in order to enhance the existing knowledge of resistance and how it in turn can be successfully managed by change agents. In this way, our purpose includes contributing with a theoretical development in regards to the change recipients’ cognitive perception of organizational change as well as providing change agents with managerial implications. Method: A qualitative research approach was applied, which included a case study design consisting of multiple cases. Semi-structured interviews and observations were the methods used for collecting the empirical data. The ten respondents were selected from one Swedish company, based on a theoretical sampling method. The data analysis method included both a within-case analysis as well as a cross-case analysis. Theoretical framework: The structure of the theoretical framework is based on three themes. The first theme considers organizational change, where our working definition and theories regarding organizational change are presented. The second theme considers resistance to change, where we define and present the theories regarding resistance to change. The third and last theme considers the change recipient’s cognitive perception of organizational change, where we provide our definitions of, and the theories regarding, the cognitive elements. Findings: The change recipients’ cognitive evaluation of organizational change have an important role, when assessing their resistance to change. In regards to the change process, knowledge required to handle the change is found to be the most important cognitive element. Change usefulness is found to be the second most important one. Advantages and disadvantages, as well as change necessity, are not found to be important cognitive elements.