Polyimides are frequently used as insulating layers in the microelectronics industry. These polymers are tough, have high thermal stability, and have favorable dielectric properties; consequently, polyimides are excellent materials for insulating layers in microelectronic devices. In this research, self-assembled monolayers are investigated for use as an adhesion promoter for metal substrates, and for corrosion protectors of the metal surface. Gold substrates modified by adsorption of 3- and 4-aminothiophenol monolayers, 3- and (4-mercaptophenyl) phthalimide (MPP) monolayers, and by reaction of the 3- and 4-aminothiophenol monolayers with the phthalic anhydride were studied using reflection absorption infrared spectroscopy, contact angle measurement, ellipsometry, and electrochemical measurements. Reactions on the monolayers are used to model the attachment of an insulating polyimide to the substrate. The covalent attachment of the anhydride is confirmed, and the efficiency of the reaction of the aminothiolphenol monolayers is investigated. The reactivity of the aminothiolphenol monolayers is found to depend on the position of the amino-group around the phenyl ring. Impedance spectroscopy is used to investigate the ionic insulating properties of these systems. The 4-mercaptophthalimide monolayer is found to have the highest monolayer resistance to ion transport. This result suggests that it forms the most densely packed monolayer. The monolayer resistance of the surfaces prepared by adsorption of the aminothiolphenol isomers followed by reaction with phthalic anhydride is much lower than the corresponding deposited mercaptophthalimide monolayers. These results suggest that the reaction efficiency is low. Impedance spectroscopy and polarization measurements suggests a higher protection efficiency for 3-mercaptophenylphthalimide. These results will be discussed in the context of the ability of the isomeric mercaptophthalimide monolayers to serve as protectors against substrate corrosion. / Ph. D.

The global progression towards sustainable energy, materials and chemicals requires novel and improved analytical tools to understand and optimize lignocellulosic biomass utilization. In an effort to advance lignocellulose characterization, gain insights into biomass processing, and obtain novel perspectives on cell wall ultrastructure, this study utilizes three principal polymer characterization techniques, namely compressive-torsion dynamic mechanical analysis (DMA), deuterium quadrupolar nuclear magnetic resonance (2H NMR) and rheo-infrared spectroscopy. A novel parallel-plate compressive-torsion DMA protocol is developed to analyze very small solvent-plasticized biomass specimens with or without mechanical integrity. The benefits and limitations of this technique are demonstrated by comparing it to a conventional tensile-torsion DMA while analyzing various solvent-plasticized lignocelluloses. The rheology of wood in various organic solvents is studied through dynamic thermal scans, Time/temperature superposition (TTS) and fragility analysis. Plasticizing solvents and wood grain orientation significantly affected the lignin glass-transition temperature. Dynamic TTS reveals that while all storage modulus data shift smoothly, the thermorheological complexity of solvent-plasticized wood becomes evident in loss component master curves. It is argued that the plasticized lignocellulose TTS is insightful and potentially useful, although it fails to satisfy the classic TTS validity criteria. Subsequently, it is justified that the fragility analysis is a better suited treatment than the WLF model to investigate cooperative segmental motions of plasticized wood. Deuterium quadrupolar NMR reveals a new perspective on the orientation of amorphous wood polymers and two distinct amorphous polymer domains: a highly oriented phase in the S2 layer of the secondary cell wall and an isotropic phase postulated to occur in the compound middle lamella (CML). If the origin of the isotropic phase is confirmed to arise from the CML, then this technique provides a way to independently investigate the morphology and phase dynamics of CML and S2 in an intact tissue, and should bring novel insights into deconstructive strategies specific to the oriented and unoriented domains. Finally the effects of a wood-adhesion promoter (hydroxymethyl resorcinol, HMR) on in-situ wood polymers are studied to elucidate the still unresolved HMR-lignocellulose interactions. DMA, creep-TTS and 2H NMR reveal that HMR increases the crosslink density and restricts the mobility of wood amorphous phase. Rheo-IR spectroscopy shows that the molecular stress-transfer mechanism is altered within the wood cell wall. / Ph. D.

Secondary xylem, commonly known as wood, is a valuable commercial commodity. Among the major components of wood are the elongated, thick-walled water-conducting cells known as tracheary elements. Understanding tracheary element differentiation and maturation is of scientific and commercial importance as it may lead to broad understanding of cellular differentiation processes as well as ways to increase both the quality and quantity of wood produced by economically important tree species. One way to begin to understand the regulation of tracheary element differentiation is to identify elements that control expression of genes associated with tracheary elements. In Arabidopsis thaliana, Xylem Cysteine Protease 1 (XCP1) is specifically expressed in tracheary elements where it catalyzes microautolysis. Thus XCP1 can serve as a useful model for identifying factors that regulate tracheary element-specific gene expression. A deletion analysis of the XCP1 promoter was conducted to identify promoter elements that are necessary and sufficient for tracheary element-restricted gene expression. Two regions required for tracheary element-specific gene expression were identified. One of these was assembled as a multimeric bait construct and used in yeast one-hybrid assays to identify candidate transcription factors that bind to the XCP1 promoter region. Subsequently, a southwestern blot analysis was used to identify transcription factors displaying specific binding to a previously reported cis-element, CTTCAAAGCCA, found in the XCP1 promoter and other tracheary element-associated genes from multiple species. / Master of Science

The pharmacologically important alkaloids morphine and codeine are found in latex of opium poppy (Papaver somniferum). Latex is harbored in laticifers, a specialized vascular cell-type. Isolation and characterization of latex-specific genes may provide a useful tool to metabolically engineer increased alkaloid production. Previous research in the Nessler laboratory identified genes that exhibit latex-specific gene expression. Latex-specific genes were an 2-oxoglutarate-dioxygense (DIOX), involved in hydroxylation, desaturation and epoxidation reactions, and two of the major latex proteins, MLP146 and MLP149. MLP-like proteins function in fruit ripening in various species that do not have the laticifer cell type. The latex-specific promoters (LSPs) for the three genes were sequenced. The 2.5 kb DIOX promoter was fused to the reporter gene Β-glucuronidase (GUS) to characterize its expression pattern. To assess the functional sites within the DIOX promoter, deletions were made 1.5 kb and 0.14 kb upstream of the ATG start codon, fused to GUS, and transformed into opium poppy, Arabidopsis thaliana, and tobacco (Nicotiana tabacum). The 2.5 kb DIOX:GUS and 1.5 kb EcoRIDIOX:GUS reporter gene constructs showed vascular specific expression in opium poppy, Arabidopsis, and tobacco. The 0.14 kb SpeIDIOX promoter deletion construct showed no activity in opium poppy, and limited expression in the shoot apical meristem and root hypocotyl axis in Arabidopsis. These results indicate that the minimum active DIOX promoter is greater than 0.14 kb. Over 1 kb of the LSPs were sequenced and analyzed for regulatory elements using the Plant cis-acting regulatory DNA elements database, PLACE (http://www.dna.affrc.go.jp/PLACE). Knowledge of the cis-elements and regulatory regions of LSPs would serve as a tool for metabolic engineering of poppy alkaloids. Sixty-five elements were conserved among 2 of the 3 LSPs. Among the cis-elements identified, some are associated with basic functions such as: light regulation, carbon metabolism and plant defense. Other elements include: WRKY elements that are binding sites of transcription factors known for signaling plant defense genes, a vascular cis-element, and a fruit specific element. The presence of plant defense and vascular cis-elements in the LSPs, correlate with the concept that latex is a protective defense mechanism found in the vascular system. The latex-specific promoters isolated and cis-elements identified in this research are potential tools for driving increased alkaloid production in opium poppy. / Master of Science

Understanding the molecular structure of DNA was considered as greatest achievement in modern biology. It helped in understanding fundamental cellular processes such as replication of DNA, nature of the genetic code and transcription. It also led to technological advancements such as DNA sequencing, genetic engineering and gene cloning. The DNA molecule is highly polymorphic in nature and its structure is dependent on environment, base composition and sequence context. B-DNA, A-DNA, Z-DNA and curved or kinked DNA are some of the well characterized double helical polymorphs. B-DNA is the most prevalent structure in vivo and it can undergo small local variations and global variations. In this thesis we refer to distinct structural property of any particular DNA sequence as deviation from fibre model B-DNA structural parameters or random sequence DNA. Structural properties of DNA are an outcome of the linear arrangement of the 4 chemically different nucleotide bases and the characteristic features of the two grooves (minor and major) arising due to the asymmetric position of glycosidic bonds of base pairs. DNA structure and properties are expected to vary along its length. Several structural features have been defined for DNA duplex, while DNA stability, bendability and intrinsic curvature are well studied and found to be biologically relevant. These three sequence dependent properties differ in their nature and information content and can be studied both at local and global levels, depending on the length of DNA fragment being examined. Majority of the work in this thesis focuses on the analysis of these three DNA structural features in promoter regions of different eukaryotic systems and their relationship with gene expression. The thesis work is divided in to five sections briefly described below. The sections discuss prevalence of the three structural features, DNA stability, bendability and intrinsic curvature in the promoter regions of six eukaryotic systems namely S. cerevisiae, D. melanogaster, C. elegans, zebrafish, mouse and human. The relationship between DNA structural features of promoter regions of S. cerevisiae with gene expression variability is discussed, followed by application of the structure-based promoter prediction algorithm ‘PromPredict’ in annotating promoter regions of six different eukaryotes. Finally, an analysis of structural features of the flanking sequences of transcription factor binding sites (TFBSs) of six transcription factors and their relationship with the DNA binding affinity is discussed. Each of the projects described below will appear as a separate chapters in the thesis. An overview of the eukaryotic transcription machinery, promoter elements and different DNA structural properties are discussed in the introduction of the thesis (chapter 1). The structural properties of DNA in the promoter regions of eukaryotic genes (chapter 2)Earlier studies in the lab reported that, apart from sequence motifs, promoter re- gions have distinct structural properties, such as lower stability, lesser bendability and more curvature compared to other genomic regions. But those studies were on small datasets and few model systems. Advancement in high-throughput tech- niques has made availability of transcription start site information for many model systems. This work was initiated with the aim of investigating the structural fea- tures in different eukaryotic systems belonging to different domains of life. The quantitative analysis of three different structural features of promoter regions of six different model systems S. cerevisiae, C. elegans, D. melanogaster, zebrafish, mouse and human has been carried out. Further, the composition of different k-mers (k=3, 4 and 6) A-tracts and G-quadruplexes has been studied. The analysis allowed us to understand the similarities and differences in struc- tural features of promoter sequences in different model systems. The core promoter sequences of S. cerevisiae, C. elegans, D. melanogaster, zebra fish, mouse and hu- man have been observed to be less stable and have lower preference for nucleosome formation. S. cerevisiae, C. elegans and D. melanogaster promoter sequences have been shown to be less bendable whereas zebrafish, mouse and human promoter se- quences are flexible in terms of bendability towards major groove as predicted fDNase 1 sensitivity model. S. cerevisiae, C. elegans, D. melanogaster core promoter regions have AT rich oligomers, whereas mouse and human core promoter regions have GC rich oligomers and G-quadruplex motifs. DNA structural features of TATA-containing andTATA-less promoters (chapter 3)Eukaryotic genes can be broadly classified as TATA-containing and TATA-less based on the presence of TATA-box in their promoter sequences. Experiments on both classes of genes have reported that, they have differences in regulation of gene ex- pression and cellular functions. In this chapter, the differences in compositional and structural features of TATA-containing and TATA-less promoters in the above mentioned model systems are discussed. The results suggested that DNA structural features of TATA-containing and TATA-less promoters are distinctly different in all eukaryotes. The TATA-containing promoters are less stable, more flexible and more curved compared to TATA-less promoters in lower eukaryotes. In mouse and hu- man genes, DNA duplex stability and G-quadruplex motifs are very distinguishing features in the two classes of promoters. DNA structural properties of eukaryotic promoter regions and gene expression variability (chapter 4) Gene expression is regulated by various external (environment and evolution) and internal (genetic) factors. Presence of sequence motifs, such as TFBSs and TATA- box, as well as DNA methylation has been implicated in the regulation of expression of some genes in vertebrates, but a large number of genes lack these sequences. Ear- lier analyses (described in previous sections) in S. cerevisiae, have shown that their promoter sequences have special structural properties, such as low stability, less bendability and more curvature compared to other genomic regions. These strutural features may play a role in transcription initiation and regulation of gene expression. This project was carried out to understand 1. What is the relationship between DNA structural features and gene expres- sion? 2. What is the relationship between gene expression and bidirectionality of a pro- moter region? For this purpose, the information of seven different gene expression variability measures, stochastic noise, responsiveness, stress response, trans variability, mu- tational variance, interstrain variation and expression divergence have been com- pared with structural features in the promoter regions. It is observed that a few of the variability measures of gene expression are linked to DNA structural prop- erties, along with nucleosome occupancy, TATA-box presence and bidirectionality of promoter regions. Interestingly, gene responsiveness is shown to be most, inti- mately correlated with DNA structural features and promoter architecture. The study highlights the importance of sequence dependent structural features in gene regulation. Promoter prediction in eukaryotes using DNA duplex stability (chapter 5) Structural property-based algorithms can discriminate promoter sequences from non-promoter sequences and are far better than sequence motif-based predictors. Compared to other structural features, low stability is found to be the most preva- lent feature in promoter regions. “PromPredict” (in-house algorithm) uses the din- ucleotide free energy values obtained from differential melting stability of DNA du- plexes as a predictor of promoters and has been successfully used earlier to annotate promoter sequences in prokaryotes and rice. Comprehensive analysis of the perfor- mance of PromPredict in S. cerevisiae, D. melanogaster, C. elegans, zebrafish, mouse and human as well as TATA-containing and TATA-less promoter regions of S. cere visiae with TSS data and 48 eukaryotic systems with translation start site (TLS) data revealed that differential stability is a good criterion for promoter prediction. DNA structure in flanking sequences of consensus motifs modulate transcription factor binding (chapter 6) Sequence specific DNA-protein interactions are essential for specific expression pat- terns during the development. There are several factors contribute to DNA-binding specificities of transcription factors (TFs). They include structure and flexibility of TFs, cofactors, chromatin environment and DNA sequence. Along with actual tran- scription factor binding sites (TFBSs), their sequence context (flanking sequences) is also shown to play a major role in gene regulation. Most of the studies have ad- dressed the sequence context at global level but very little is understood about the role of sequences flanking TFBSs in binding of transcription factors. This project was initiated with the aim of understanding the effect of flanking sequences of TFBSs in transcription factor binding affinity. In vitro DNA binding information of six different transcription factors (with three types of DNA bind- ing domains, Zinc finger (GATA4), home domain (AbdA, AbdB and Ubx) and bZIP (fos-jun and Nfil3)) was provided by Aseem Ansari’s lab. The compositional and structural features (minor groove width, propeller twist, wedge and free energy) are compared with the DNA binding profiles of 12mers (or 8mers) of six different transcription factors. It has been observed that some of the DNA structural proper- ties of flanking sequences are strongly correlated with binding affinity. For GATA4 sequences, binding affinity is negatively correlated to GC content or minor groove width at their 5′ -flanking region, showing the significance of narrow minor groove at 5′ -region. On the other hand, the binding affinity of bZIP proteins is negatively correlated to wedge angles, whereas in case of homeodomain proteins, it is posi- tively correlated to propeller twist and GC content. Thus, this study highlights the differential preference for flanking sequences outside the core binding motifs of six different TFs, which interact with DNA through α-helix. ‘The relationship between transcription pre-initiation complexes and gene ex- pression variability in S. cerevisiae’ is briefly described in the appendix section of the thesis. General conclusion Overall, the results presented in this thesis indicate that DNA sequence based structural features are unique to promoter regions and play an important role in gene regulation. Local structural features of flanking sequences of transcription factor binding sites are also instrumental in determining the DNA binding affinity of transcription factors.

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Zymoseptoria tritici est l'un des dix plus importants champignons pathogènes des plantes. Son impact économique sur la production de blé et ses caractéristiques biologiques (dimorphisme levure-hyphae, hémi-biotrophie, populations sexuées et diversifiées) fait de Z. tritici un organisme unique parmi les champignons pathogènes des plantes. Au cours des dix dernières années, il a suscité un intérêt croissant de la communauté scientifique conduisant au développement d'outils génomiques et génétiques. Ces efforts ont permis de mieux comprendre les mécanismes impliqués dans sa pathogénie et son évolution. Nous avons focalisé notre étude sur les trois «Mitogen-Activated Kinases» (MAPK) ZtFus3, ZtHog1 et ZtSlt2 de Z. tritici nécessaires au succès de l’infection. Nous avons réalisé une caractérisation phénotypique détaillée du mutant de délétion ZtSLT2 lors de l'infection du blé et du développement fongique in vitro. Nous avons montré que le mutant ΔZtslt2 est non pathogène pour les feuilles de blé, même lorsque la pénétration stomatique est court-circuitée par injection de spores dans la feuille, ce qui suggère que ce mutant présente un défaut dans la colonisation des tissus de la plante. Pendant la croissance in vitro, ZtSLT2 est nécessaire à la pigmentation, des colonies, l’émergence des hyphes aériens, la formation de biofilm et l’hydrophobicité de la colonie. Ces phénotypes sont des marqueurs d'un processus développemental qui se produit pendant le vieillissement de la colonie de Z. tritici (développement de colonies pigmentées et hydrophobes portant des hyphes aériens blancs). Ce processus développemental survient à des moments différents selon le milieu de culture et la température, le plus rapide étant sur milieu pauvre «Pomme de terre Glucose» (PD) à 25 °C (4 jours) et le plus lent sur milieu riche complet «Extrait de Levure, Peptone, Glucose» (YPD) à 18 °C (18 jours). Nous avons montré que les gènes codant pour des enzymes impliquées dans la biosynthèse de la mélanine, des α-1,3-glucanes et des hydrophobines sont surexprimées au cours de ce processus développemental dans la souche sauvage, en particulier après trois jours de culture sur PD à 25 °C par rapport aux autres conditions. Cette surexpression nécessite que la voie ZtSLT2 soit fonctionnelle. L’analyse transcriptomique (RNAseq) de ces conditions différentielles est en cours pour identifier le réseau de gènes nécessitant la protéine Slt2 pour leur expression. Ces gènes cibles de ZtSLT2 sont des facteurs de pathogénicité putatifs.Nous avons également développé un nouvel outil moléculaire pour Z. tritici. Nous avons montré que les promoteurs pMoNIA1 et pZtNIA1 des gènes codant les nitrates réductases de Magnaporthe oryzae et Z. tritici, respectivement, sont régulés par la source d’azote du milieu de la même façon chez Z. tritici. L’expression de gènes sous le contrôle de ces deux promoteurs est maximale en présence de nitrate comme seule source d'azote, mais réduite en présence de glutamate. Ces promoteurs peuvent donc être utilisés pour l'expression conditionnelle de gènes et le remplacement de promoteur chez Z. tritici. Ils seront utiles pour contrôler l'expression des allèles constitutivement actifs des MAP kinase kinases dans le but d’activer les voies des MAPK de manière conditionnelle. / Zymoseptoria tritici is one of the ten more important fungal plant pathogens. Its economic impact on wheat production and its biological characteristics (yeast-fungal dimorphism, hemi-biotrophy, sexual and highly diverse populations) make Z. tritici unique among fungal plant pathogens. It has therefore drawn attention of the scientific community during the last ten years, leading to the development of genomic and genetic tools. These efforts have improved our understanding of its pathogenicity and evolution. We have focused our study on the three Z. tritici Mitogen-Activated Protein Kinase (MAPK) signalling pathways (ZtFUS3, ZtHOG1, and ZtSLT2) which are required for pathogenicity. We provided novel insights in the role of ZtSlt2 MAPK signalling pathway using a detailed phenotypic characterization of SLT2 deletion mutant during wheat infection and in vitro development. We showed that SLT2 is non-pathogenic on wheat leaves, even when stomatal penetration is bypassed by spore injection, suggesting a defect in leaf colonisation. During in vitro growth, SLT2 is required for melanisation, aerial hyphae emergence, biofilm formation and colony hydrophobicity which are markers of a developmental switch occurring during Z. tritici colony aging (development of melanised and hydrophobic colonies supporting abundant white aerial hyphae). This developmental switch occurs at different times depending on media and temperatures, quickest being on poor plant-derived Potato Dextrose (PD) medium at 25°C (4 days) and slowest on rich complex Yeast Extract Peptone Dextrose (YPD) medium 18°C (18 days). We provided evidence that genes encoding enzymes involved in both melanin and α-1,3-glucan biosynthesis, and hydrophobins are up-regulated during this developmental switch in wild type, in particular at 3 days on PD at 25°C compared to other conditions. This up-regulation clearly requires a functional ZtSLT2 pathway. Transcriptomic analysis (RNAseq) of these differential conditions is ongoing to identify the network of genes requiring SLT2 for their expression. These SLT2 target genes are putative pathogenicity factors. We also provide a new molecular tool for Z. tritici. We showed that pMoNIA1 and pZtNIA1 promoters from nitrate reductases encoding genes of Magnaporthe oryzae, and Z. tritici, respectively, are nitrogen-responsive in Z. tritici to a similar extent. They are fully expressed in presence of nitrate as sole nitrogen source and down-regulated in presence of glutamate, showing they are suitable for conditional gene expression and promoter replacement in Z. tritici. These promoters will be useful to control the expression of constitutively active alleles of MAP Kinase kinases in order to activate MAPK pathways in a conditional manner.

Sammanfattning Kandidatuppsats i företagsekonomi III, Organisation 15 hp, 2FE78E, Ekonomihögskolan vid Linnéuniversitetet i Kalmar, VT 2023 Författare: Alicia Ketabati Augustinsson och Ida Johansson Handledare: Annika Schilling Examinator: Mikael Lundgren Titel: Sprudlande ambassadör eller nitisk kritiker - En studie hur rekryteringsprocessen kan användas för att utveckla en organisation i offentlig sektor   Syfte Syftet med studien är att öka förståelsen för hur undersökning av kandidatupplevelsen kan ligga till grund för utveckling av rekryteringsarbete och employer brand i offentlig sektor. Syftet nås genom att samla in information om kandidaters upplevelse av rekryteringsprocessen i en kommun under en specifik tidsperiod.  Metod En tvärsnittsstudie som med hjälp av en parallell användning av kvantitativ och kvalitativ metod undersöker kandidaters uppfattning om rekryteringsprocess de varit delaktiga i för att genom dessa mätningar öka förståelsen för hur organisationer kan utveckla sin rekryteringsprocess och sitt employer brand.  Slutsats Från mätning av kandidatupplevelsen kan organisationen skapa index och mål att arbeta mot för att utveckla organisationen. Mätningarna kan mynna ut i nyckeltal för organisationen att använda i utvecklingsarbetet för att lättare se förändringar. Arbetsgivare i offentlig sektor bör få en helhetsbild av hur det egna varumärket uppfattas av inte bara arbetsgivarrepresentanter utan även externa parter som exempelvis kandidater. Nyckelord Rekryteringsprocess, employer branding, rekrytering, kandidatupplevelse, net promoter score, index, professionella relationer, förväntningar, offentlig sektor / Abstract Bachelor Thesis Business Administration III, Organization 15 hp, 2FE78E, School of Economics at Linnaeus University of Kalmar, Spring 2023 Authors:  Alicia Ketabati Augustinsson och Ida Johansson Advisor: Annika Schilling Examinator: Mikael Lundgren  Title: Exuberant ambassador or zealous critic - A study of how the recruitment process can be used to develop an organization in public sector    Purpose The aim of the study is to increase the understanding of how examination of the candidate experience can form the basis for the development of recruitment work and employer brand in the public sector. The purpose is achieved by collecting information about candidates' experience of the recruitment process in a municipality during a specific period of time. Method A cross-sectional study which, with the help of a parallel use of quantitative and qualitative methods, examines candidates' perception of the recruitment process they have been involved in in order to increase the understanding of how organizations can develop their recruitment process and their employer brand through these measurements. Conclusion From measuring the candidate experience, the organization can create indexes and goals to work towards to develop the organization. The measurements can result in key figures for the organization to use in development work to more easily see changes. Employers in the public sector should get an overall picture of how their own brand is perceived by not only employer representatives but also external parties such as candidates. Key words Recruitment process, employer branding, recruitment, candidate experience, net promoter score, index, professional relationships, expectations, public sector

The video streaming business has grown substantially during the last decades. To optimize the user experience in video streaming, it is important to know how the user satisfaction relates to the technical qualities for the video streaming services, such as bufferings and startup times.  The Net Promoter Score (NPS) is a widely used management tool used in surveys to measure customer satisfaction and loyalty. The users are categorized into three user groups based on a survey question. This thesis investigates whether it is possible to find correlations between the three user groups based on NPS ratings and measured technical qualities from video streams. Initial data exploring through information visualization suggested that the data should be separated into live streams and video-on-demand. Statistical analysis showed that the NPS user groups have no correlations to how long the users are watching the streams, nor to how long the video takes to start. The results showed, that the users watching live streams seem to be more sensitive to lower qualities than those watching video- on-demand. However, this could also be due to the fact that the measured technical qualities during live streams are generally lower. The buffering and the seek time proved to have correlations to the measured user satisfaction, but several other factors such as the actual video content could also have big impacts on the user’s ratings. The users which had experienced more buffering and longer seek times were more likely to rate the service with a lower score, than the average user. / Mängden videor som streamas över Internet har ökat väsentligt under de senaste årtiondena. För att kunna optimera upplevelsen för de som streamar videor är det viktigt för företagen som erbjuder dessa tjänster att veta hur kundnöjdheten relaterar till de tekniska egenskaperna. Dessa kan inkludera faktorer såsom buffring och starttider. Net Promoter Score (NPS) är ett verktyg som används inom många olika branscher för att mäta kundnöjdhet och lojalitet. Användarna delas in i tre grupper beroende på hur de svarar på en enkätfråga. Detta examensarbete undersöker huruvida det är möjligt att hitta korrelationer mellan kundnöjdhet baserad på de tre användargrupperna från NPS-verktyget och uppmätta tekniska kvaliteter från en streamingtjänst. Efter att inledande informationsvisualiseringar påvisade skillnader mellan live-strömmar och video-on-demand har dessa grupper hanterats separat. Statistisk analys visade att de tre NPS-grupperna inte har några korrelationer med starttiden eller hur länge användarna tittar på videor. Resultatet visade även att användarna som tittar på live-strömmar verkar vara känsligare för lägre tekniska kvaliteter än de som tittar på video-on-demand. Detta kan dock även bero på att de uppmätta tekniska egenskaperna under live-strömmarna generellt är lite lägre. Buffringen och söktiden visade sig ha samband med den uppmätta kundnöjdheten, men flera andra faktorer, såsom det faktiska videoinnehållet, kan också ha en inverkan på användarnas betyg. Användarna som hade upplevt mer buffring och längre söktider var mer benägna att ge tjänsten ett lägre betyg än den genomsnittliga användaren.

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