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The tear film is a thin liquid layer enveloping the cornea and conjunctiva. It serves as a crucial protective barrier safeguarding the ocular surface from environmental factors. Its functions also include ensuring optimal hydration and maintaining a consistently smooth optical surface. The tear film consists of three discernible layers. The outermost layer is the remarkably thin tear film lipid layer, measured on the nanometer scale, yet crucial for impeding evaporation and maintaining ocular surface homeostasis. The tear film lipid layer forms from meibum: a complex mixture of lipids secreted by Meibomian glands. Meibum mainly consists of lipids from five different classes, with wax esters constituting about 50 % of meibum’s composition. The majority of tear film lipids are branched. Branched lipids are methyl-branched either from the penultimate or antepenultimate carbon, with the former being more common. Due to challenges in obtaining sufficient and uncontaminated meibum samples, there is a high demand for synthetically produced lipids. Pure samples of lipids of varying structures are needed as standards in studies regarding meibum composition. Additionally, lipids and lipid mixtures are required for biophysical studies concerning tear film models and researching the molecular mechanisms associated with ocular surface diseases. Given the demand for various tear film lipids, it is surprising that there have been no prior attempts to synthesize branched lipid species or study their effect on lipid assembly, despite their prevalence in meibum. To meet the demand for various tear film lipids, especially branched species, we aimed to design a synthetic approach capable of producing a wide range of such tear film lipid analogs. This method proved successful in synthesizing the most abundant tear film lipid, the iso-branched wax ester C18:1/26:0. The results of this synthesis are presented in this thesis.

Since the release of the Lord of the Rings movie trilogy (2001, 2002, 2003) New Zealand has been visited by millions of people wanting to experience the mythical Middle-earth they saw on the silver screen. The Kiwi director Peter Jackson's interpretation of the epic story of adventure, sacrifice and friendship in the fantasy land created by the English author J.R.R. Tolkien has widely be seen as an 'authentic' and New Zealand as a fair representation of the Middle-earth with its lush valleys, barren wastelands and remote mystical mountains. Film tourism contains any tourist activity that is induced by the viewing of the moving image. It is a relatively new field of study and even though the Lord of the Rings is the most studied topic within the film tourism literature, the on-site tourism experience process is still not fully understood. The research concentrates on the experiences of three different types of Lord of the Rings tours; Hobbiton Movie Set is the only built set left in New Zealand, Nomad Safaris besides the movies also concentrates to the other activities and the rugged landscape around the Queenstown area, whereas Adventure Safari Movie Tours tries to compensate the fact all of its locations are in public parks by re-enactments and movie clips. The main focus of the study is to find out how the tour participants experience their tours; what elements are in present in a film tourism experience, and what qualities make the locations and experiences authentic? As the main source of material is used reviews written on the TripAdvisor website. Triangulation is the most appropriate method to analyse user-generated data as it gives an opportunity to combine qualitative and quantitative methods. Content analysis can be used to analyse the reviews, but because of the subjectivity of experiences it is also relevant to compare the results of the study to the researcher's own experiences and observations from the chosen Lord of the Rings tours. Film tourist experience is a complex research matter as it is highly subjective sum of many parts. The experience starts already in the planning phase when the expectations are formed, and the anticipation builds up during the travel to the attraction. The experience at the attraction itself holds in both the physical and social aspects, and authentic locations and interactions are the key to the satisfying film tourist experience. With the help of the guides' interpretative skills the narratives turn into myths and reality merges with hyperreal fantasy. Memorabilia, such as rocks, t-shirts and pictures gained from the attraction help in the post-trip recollection phase and work as a status symbols. The results indicated that the sample reflected the typical Lord of the Rings tour participant as identified in previous research, with reviewers being mainly part of the working-age population (25-49 year olds), predominantly female, and from the Western and English-speaking markets, majority being from Australia and USA. The biggest negative factor in the film tourist experience is the bad value for the money. Whereas a good tour guide is the most important part in the value creation. Passionate tour guides are even able to turn weaker locations into experiences worth paying. The scenery seems to be the balancing factor, as a bad tour guide combined to the beautiful location seems to lead to an average experience. Hobbiton is seen as the most authentic and iconic of the three studied locations because of its lifelike details and the surrounding pastoral landscape. The set is the actual piece where the outdoor scenes of the Hobbiton where filmed. The Nomad Safaris participants on the other hand immerse into the beauty of the natural landscape and are not even missing any set structures.

In this master’s thesis biochemistry of cancer, glucose transporters in cancer therapy and the importance of imaging are explored, and the synthesis of applicable glycoconjugates is introduced. Bioorthogonal applications of functionalizable glycoconjugates, such as, drug delivery, imaging, cancer therapy and studying biological phenomenon inside living cells, are reviewed. The basic theories on biochemistry of cancer, cancer imaging with [18F]-2-fluoro-2- deoxy-D-glucose-Positron Emission Tomography (18FDG-PET) and glucose transporters are discussed in the literature review section. The databases used to scan relevant literature were SciFinder and Helsinki University Library (Helka) web article search. The first of the glycoconjugates synthesized, 1,2,3,4-Tetra-O-benzyl-6-O-propargyl-D- glucopyranose, is already published in the literature as an intermediate on the route towards improved delivery agents for BNCT. The final product has been assessed in in vitro studies, cellular uptake and cytotoxicity studies giving outstanding results. The boron delivery capacity of the molecule is prominently superior compared to the agents in clinical use at the moment. The glucoconjugate can also be functionalized for the use in other applications with the use of the propargyl conjugation site. The second synthesis covers two potential bioorthogonal chemistry glycoconjugates: α-D-Mannopyranoside, phenyl 6-azido-6-deoxy-3,4-O-[(1S,2S)-1,2- dimethoxy-1,2-dimethyl-1,2-ethanediyl]-1-thio-, 2-trifluoromethanesulfonate and -2-(4- methylbenzenesulfonate). These mannopyranoside derivatives are functionalizable glycoconjugates with a wide range of applications in biological research. They both contain three conjugation sites that can be functionalized for further applications. The carbohydrate part is recognized by cells, the azide functional group at C-6 can be modified through click chemistry, the thiol can be activated in glycosylation reactions and the triflate or tosylate in C-2 can be substituted in an SN2 reaction, for example with [18F] to enable imaging. This elegant toolkit offers a wide range of biorthogonal opportunities for chemists and biologists alike.

Ensuring quality and reliable wireless network in crowd events, such as sport events in the stadium or exhibitions in large convention halls, has been challenging. Standard 802.11 Wi-Fi is based on CSMA (Carrier sense multiple access) technology; however using TDMA (Time Division Multiple Access) instead might bring benefits such as energy savings, fair use of bandwidth and more predictable performance in crowded networks. Using TDMA with standard Wi-Fi hardware has been proposed before, but the proposed solutions would require changes to the MAC layer, which means modifying NIC drivers and even firmware. The goal of this thesis is to investigate, whether a simple TDMA could be implemented on the application layer for crowded Wi-Fi networks. 'Application Layer TDMA' means that the network stack would be left unchanged, and the applications on different devices would agree on a schedule of sending packets on their dedicated time slots. The experiment of the thesis has been carried out in an RF shielded laboratory in Helsinki University and from the experiment we have evaluated the performance of the application layer TDMA and compared with CSMA/CA.

DP-SGD (Differentially Private Stochastic Gradient Descent) is the gold standard approach for implementing privacy in deep learning settings. DP-SGD achieves this by clipping the gradients during training and then injecting noise. The algorithm aims to limit the impact of any data point from the training dataset on the model. Therefore, the gradient of an individual sample will give information until a certain point, thus limiting the chances of an inference attack discovering the data used for the model training. While DP-SGD ensures the privacy of the model, there is no free lunch, and it has its downsides in terms of the utility-privacy trade-off and an increase in computational resources for training. This thesis aims to evaluate different DP-SGD implementations in terms of performance and computational efficiency. We will compare the use of optimized clipping algorithms, different GPU processing unit architectures, speed-up by compilation, lower precision in the data representation, and distributed training. These strategies effectively reduce the computational cost of adding privacy to the deep learning training compared to the non-private baseline.

The aim of the research was to explore the new possibilities of indoles activation via photoredox catalysis. The interest in general was focused on synthesis of related biaryls through C(sp2)-C(sp2) radical mediated cross-coupling reactions. Conducted literature overview revealed that photochemical methods are undergoing rapid development, being highly promising tools in a way to our goals. As a result, it was discovered that 3-bromoindoles may interact with acridinium and iridium based photocatalysts, producing free radicals that can be coupled with aryl of interest. The further method development helped to optimize the reaction condition to achieve good to excellent biaryls yield. In addition, new ground-up synthetic routes toward several indoles, their derivatives and one of Fukuzumi catalyst were disclosed and supplemented by spectral data. The obtained results might also be useful for developing more complicated dual catalysis systems.

Software development industry has been revolutionized through adoption of software develop- ment methods such as DevOps. While adopting DevOps can speed up development through collaborative culture between development and operations teams, speed-driven adoption can have an adverse impact on security aspects. DevSecOps is a concept that focuses on embed- ding security culture and activities into DevOps. Another contributing factor to the more agile development landscape is the widespread adoption of open source components. However, the risk of putting too much trust into the open source ecosystem has resulted in a whole new set of security issues that have not yet been adequately addressed by the industry. This thesis is commissioned by Neste Corporation. The company has set an initiative to in- corporate methods that enable better transparency, agility, and security into their software development projects. This thesis collects research data on secure software development prac- tices by combining findings of a literature review with a case study. The qualitative case study is done by interviewing eight stakeholders from four different software development teams. The literature review shows that securing software is very much an ongoing effort, especially in the open source ecosystem. Therefore, it might be not surprising that the results from the case study revealed multiple shortcomings on the subject matter despite obvious efforts from the participating teams. As a result, this thesis presents potential ideas for the case company to consider integrating into their software development projects in order to kickstart their secure software development journey.

Concerns about the state of the environment and the global climate change has created a need for more efficient and greener ways to produce chemicals and fuels. One solution to these challenges is to find improved ways of utilizing biomass. This thesis deals with the valorization of pectin rich biomasses. Bioengineering yeast to express the alternative galacturonic acid catabolism pathway opens up an opportunity to use these underutilized biomasses in a more efficient way. In order to bioengineer yeast, understanding of the metabolic pathways and the enzymes functioning on these pathways is required. In order to map out certain degradation steps, access to non-commercial compounds and structural analogues is a necessity. The aim of this thesis was to develop a synthetic route to D-tagaturonate, and its structural analogues, which are intermediates on the galacturonic acid catabolism pathway. The chosen multistep synthetic route to D-tagaturonate proved to be challenging. The end product was not obtained, however, the laboratory work showed that the synthetic route is feasible after some minor adjustments. On a general level, new information on the limitations of widely utilized protective groups could be uncovered. These findings will help to optimize the synthetic route to D-tagaturonate. In addition, these findings show that there is still room for improvement in orthogonal protective group strategies applicable to the synthesis of complex organic molecules such as carbohydrates.

Boron neutron capture therapy (BNCT) is an emerging cancer treatment method that is currently limited by suboptimal boron delivery strategies. A wide range of biomolecules have been investigated as potential tumor targeting boron carriers. Carbohydrates excel on several aspects by providing high solubility and low cytotoxicity. This work focuses on the synthesis of an orthogonally protected glycoconjugate for a GLUT1 targeting approach to BNCT. Knowledge of suitable glycoconjugate structures for this targeting strategy is emerging, and the aim of this work was to explore further functionalization of these structures, which will be necessary for future labeling of the boron carriers. The seven-step synthesis of an orthogonally protected mannopyranoside – and structural determination with NMR spectroscopy and mass spectrometry – is described in detail. The attachment of a boron cluster to the target molecule was performed, and early-stage fluorination trials were carried out. While important insights were obtained from these functionalization attempts, the functionalization of the target molecule will require some additional effort in the future. The protecting group strategies are currently being redesigned based on the information obtained through this work.

Software companies have problems connecting business goals to actual software development tasks. This means that a lot of software development is done without linkage to business goals, which can lead to wasting time and money, and to bloated- and hard to maintain software and failed software projects. Roadmapping is a popular method to communicate future product development efforts but a problem with roadmaps is that they usually do not communicate the value the roadmapped future work is expected to create. This thesis presents an action oriented case study on three software planning techniques that fit into a lean software product development organization. The case study is about benefits of using Lean canvas, Impact mapping and Lego serious play as tools for value-oriented product development planning. Lean canvas and Impact mapping are promising techniques for helping a company connect business goals to actual software development tasks. They therefore aid in avoiding waste and creating value through putting effort only on the development tasks that create value. Lego serious play is an strategic planning method that utilizes Lego bricks and the knowledge of the whole development team to improve decision making and building shared knowledge. Results from the study show that Lean canvas proved to fulfil its promises to be a lightweight technique that improves shared understanding of the business model. Lego serious play has a similar benefit of improving shared understanding in the team, but it is more geared towards visualizing problems and finding solutions for them. Impact mapping was proved to be an effective way to find value creating tasks and to visualize the value assumptions behind each task. Based on these findings, an approach for value-oriented roadmapping is sketched.