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  • Anttila, Teemu T. T. (2017)
    Industrial clusters are a worldwide phenomenon and a vital economic development strategy. The approach is defined to be an interrelationship between its participants, suppliers and related industries that produce synergy in a particular location. Clustering has become to be a crucial feature in nation’s economic development. However, the approach has not yet been studied widely in Sub-Saharan African countries and the existing number of empirical studies are limited. Therefore, this leaves a gap for an up-to-date study to investigate the possibilities of developing an efficient forest industry cluster in Angola. The purpose of the study was to critically assess and to define the potential of different wood processing industries in connection to develop an efficient forest industry cluster in the Province of Huambo. The objective was to create a comprehensive picture of the existing market situation through a field study and to develop the future concept of wood processing industries. Research methods were qualitative in the empirical part of the study and quantitative in the investment calculations. The primary data were collected through a semi-structured field interviews and observations of existing operators. Interviews were conducted in January and February 2017 to obtain knowledge about the prevailing market situation and about the existing wood product manufacturers. The data were collected with nine interviews, which were transcribed. Pictures and video clips were recorded to support the observations from the factories in the data collection. Based on the field study and observations, investment alternatives were decided and calculated to different wood processing industries. Profitability of the investments were calculated with the Net Present Value (NPV), Internal Rate of Return (IRR), Multiple of Invested Capital (MOIC) and Wood Paying Capability (WPC) at stumpage. Attention was paid to the uncertainty in the calculations with the help of sensitivity analysis. The literature review was based on the cluster theory, collective efficiency and the capital expenditure projects. As a result of this study, an investment model was developed in a shape of a cluster. The cluster model contains five different dimensions: sustainable plantation forestry, production of primary wood products, production of secondary wood products, wood residues sufficient utilization and production of sustainable energy. This study suggests that veneer peeling and sawn timber production could be selected for the primary wood production, carpentry and furniture for the secondary processing and wood residues to produce sustainable energy. The corresponded 10-year investments NPVs varied from USD 606 000 to USD 974 000 at an interest rate of 15%. The maximum IRR achieved was 31.6% and the minimum was 16.8%. The highest WPC at stumpage achieved was USD 69.8 and the lowest was USD 44.1. The MOIC ranged between 2.4 and 4.0 times the invested capital. This study suggests that the Company could develop an efficient forest industry cluster around veneer peeling with the support from other wood processing industries to the region.
  • Krause, Tina (2023)
    The use of fossil fuels is a significant contributor to greenhouse gas emissions, making the transition to zero-carbon energy systems and the improvements in energy efficiency important in climate change mitigation. The energy transition also puts the citizen in a more influential position and changes the traditional dynamics between energy producers and consumers when citizens produce their own energy. Furthermore, due to the opportunity and capacity of the demand side, the energy transition places a greater emphasis on energy planning at the local level, which requires new solutions and changes in the management of the energy system. One rising phenomenon is the potential of bottom-up developments like energy communities. Within the building sector, housing cooperatives have started to emerge as energy communities, offering a way to address the energy transition through bottom-up-driven energy actions that provide renewable energy and other benefits to the local community. This master thesis examines housing cooperatives' energy communities and their role in the energy transition. The research addresses the shared renovation project in Hepokulta, Turku, seen from the energy community perspective. Furthermore, the research highlights the importance of niche development in sustainable transition, acknowledging energy communities as socio-technical niches where development is partly embedded in renewable energy technology and partly in new practices. The concept of energy community is therefore analysed through the lens of Strategic Niche Management, which focuses on expectations, networks, and learning. This research aims to analyse how residents in Hepokulta perceive the energy community project through the niche processes and how the development of energy communities might affect urban development. Analysing the residents' perceptions provide insight into the energy community characteristics and the relationship between residents and the project development processes. Additionally, the analysis identifies matters that could be changed to improve the development. The thesis is a mixed methods research combining quantitative and qualitative data, which was collected through a survey sent to the eight housing cooperatives in Hepokulta. The research showed that residents perceive the shared project in Hepokulta as essential for the area's development. Moreover, many residents overlooked the social aspects of the development, highlighting the absence of the energy community perspective in the renovation. The findings suggest some weaknesses within the three niche processes, including the early involvement of residents and communication. Furthermore, although the residents perceived themselves as important actors and the literature emphasised the importance of the demand side in future energy systems, the research revealed that the connection between project development and the residents is still lacking. However, the analysis indicates that introducing additional actors could help the energy community develop. External assistance could, for instance, benefit the housing cooperatives by facilitating improvements in the decision-making processes, the network between actors, and the sharing of information and skills.
  • Ruuska, Ronja (2023)
    This master’s thesis includes two sections: the present summarizing report and the article manuscript. The purpose of the study is to explore the benefits of an acceptance and commitment therapy (ACT)-based intervention course to university students’ well-being, using both quantitative and qualitative methods. The COVID-19 pandemic has decreased university students’ well-being and increased their risk of burnout. The declined state of student well-being calls for measures in exploring ways of promoting student well-being and preventing study-related burnout. The intervention course aimed to increase students’ psychological flexibility and organized studying skills, as means to positively impact their well-being and studying. A total of 189 participated in the study in the spring of 2021. Students’ risk of burnout was measured pre- and post-intervention, to statistically define whether students experienced that the course impacted their risk of burnout. To explore the course benefits in depth, students’ written reflective reports post-intervention were analyzed using abductive content analysis. The results were statistically compared according to the risk of burnout group assigned pre-intervention. The results showed that the intervention course led to a positive change in students' risk of burnout. The content analysis revealed seven main categories of benefits of the course: 1. improved general well-being, 2. improved self-knowledge, 3. increased psychological flexibility, 4. improved study practices and study motivation, 5. increased self-compassion, 6. gained peer-support, and 7. improved organized studying. These benefits were experienced by students regardless of their initial risk of burnout. The study highlights the potential of ACT-based intervention courses in improving the well-being and studying skills of university students, suggesting a need for further research on burnout prevention through such measures. The prospective publication channel for the research article manuscript is Research in Higher Education by Springer.
  • Nowlan, Kirsten Helene Anna-Marie (2020)
    Mucosal associated invariant T (MAIT) cells are a fairly recently described population of innate-like T cells. In humans, MAIT cells represent an exceptionally abundant population in the blood, where they account for 1–10% of all T cells. However, compared to conventional T cells, which can display an almost unlimited T cell receptor (TCR) repertoire, the specificities of MAIT cell TCRs are limited. This evolutionarily conserved subset displays a semi-invariant TCR which recognises riboflavin metabolites, produced by a wide range of bacteria and fungi, and presented on the major histocompatibility complex (MHC)-class I related (MR1) molecule. The function and significance of MAIT cells in health and disease have only started to be unravelled, and it is becoming increasingly clear that MAIT cells are also modulated in non-microbial diseases. Interestingly, MAIT cells have been shown to exhibit a relatively high expression of the transcription factor, Helios, compared to most other T cell subsets. The function of this translational activator and repressor, encoded by the gene IKZF2, in the MAIT cell population remains obscure. This study focused on the functional role Helios may play in regulating the activation of MAIT cells. Thus, by using siRNA to silence Helios expression, and flow cytometry to analyse any potential alterations in MAIT cell activation markers, we aimed to be able to characterise the kinetics and functional role of Helios in peripheral MAIT cells of healthy individuals. Here, we clearly established a striking upregulation of Helios in MAIT cells following 24 hours of stimulation. Moreover, we were able to achieve a >50% knockdown of Helios at the protein level, in this subset of T cells. Nevertheless, no significant difference in any of the activation markers we investigated was present between the MAIT cells with reduced Helios expression and their controls. This could, however, of occurred as a result of the toxicity that the transfection had on the functionally of the T cells. From these results, it is difficult to conclude any clear role for Helios in the activation of MAIT cells, and consequently, further research needs to be performed before any clear conclusions can be drawn.
  • Luostarinen, Marika (2022)
    This master’s thesis focuses on exploring the impact of basic income experiments and pilots in the Global North on the social dimension of well-being and their implications for families. The background to this research is that basic income has a definition but often basic income experiments do not fully fulfil this definition. Studies indicate that a good economic situation has a positive effect on well-being. Studies also suggest that social relationships, social activities, a sense of belonging, and good interpersonal relationships can increase well-being. By supporting families, society supports individuals and the people close to them. Supporting parents in particular often has a direct impact on the well-being of their children. However, previous studies have focused more on the effects of basic income on employment. The aim is to gain a deeper understanding of the impact of basic income experiments on the social dimension of well-being and the impact on families. Previous research on the effects of poverty on the well-being of families and individuals through social relationships and a sense of belonging serve as a frame of reference for this thesis. The research questions were: What are the results of basic income experiments in the Global North regarding the social dimension of well-being? Based on these results, what kind of problems could basic income address? News articles from the Basic Income Earth Network website (BIEN, from January 9, 2014 to May 31, 2022 (n=2250) are used as the data for this thesis. The methods of the thesis were web scraping and a scoping review. The material of the thesis consisted of the analysis of the results of ten different experiments. Therefore, the final results from the experiments were collected through a scoping review of ten reports for more in-depth analysis (n=10). The results of the thesis indicated that basic income helped those who participated in basic income experiments to deepen their social relationships, improved their sense of belonging, relieved stress, and had a positive effect on family relationships. However, the results also suggested that well-being may be a subjective experience and many factors may have influenced these outcomes. In addition, the results showed that the effects on individuals as well as families were positive and similar, but there were also differences. Future research could focus on a more in-depth study of the effects of the basic income experiment on social well-being and sense of belonging. In addition, the long-term effects should be examined, in particular the impact of basic income on the increased risks of poverty over the course of life and at different stages of life.
  • Heinonen, Ava (2020)
    The design of instructional material affects learning from it. Abstraction, or limiting details and presenting difficult concepts by linking them with familiar objects, can limit the burden to the working memory and make learning easier. The presence of visualizations and the level to which students can interact with them and modify them also referred to as engagement, can promote information processing. This thesis presents the results of a study using a 2x3 experimental design with abstraction level (high abstraction, low abstraction) and engagement level (no viewing, viewing, presenting) as the factors. The study consisted of two experiments with different topics: hash tables and multidimensional arrays. We analyzed the effect of these factors on instructional efficiency and learning gain, accounting for prior knowledge, and prior cognitive load. We observed that high abstraction conditions limited study cognitive load for all participants, but were particularly beneficial for participants with some prior knowledge on the topic they studied. We also observed that higher engagement levels benefit participants with no prior knowledge on the topic they studied, but not necessarily participants with some prior knowledge. Low cognitive load in the pre-test phase makes studying easier regardless of the instructional material, as does knowledge on the topic being studied. Our results indicate that the abstractions and engagement with learning materials need to be designed with the students and their knowledge levels in mind. However, further research is needed to assess the components in different abstraction levels that affect learning outcomes and why and how cognitive load in the pre-test phase affects cognitive load throughout studying and testing.
  • Li, Tingyang (2020)
    This thesis examines the macroeconomic impact of Covid-19, constructing a DSGE model incorporating wage rigidity and consumption habit. This paper captures the characteristics of the Finnish economy, such as high wages and high consumption habits, and aims to analyze the macroeconomic impact of Covid-19 in Finland. Based on the New Keynesian DSGE model and combined with the SVAR method, focusing on the adverse effects of Covid-19 and analyzing how to mitigate its negative effects. After building the DSGE model, Bayesian estimation was performed using the parameters of Kilponen (2016) as the prior distribution, after which impulse response analysis was performed. At the same time, the effectiveness of fiscal policy and monetary policy is analyzed. The results of the empirical model support the conclusions in the theoretical model. The results show that the decline in utility due to insufficient consumption preferences significantly impacts consumption and output, causing aggregate consumption to decline and remain below steady-state levels for a long time. The level of labor supply is negatively affected by underconsumption. But the shock to consumer preference increased investment, offsetting some of the negative shock to output. Inflation and real interest rates also took a downward hit. Real interest rates first fall and then rise but remain below a stable level for a long time as the supply of capital rises when the demand for capital falls. A negative shock to technology causes aggregate consumption and aggregate output, and labor and capital goods to fall. In contrast, a fall in capital value causes Tobin's q to fall. Looking at the impact time of the impulse response, we find that the negative impact on macroeconomic variables is large and long-lasting. A positive government spending shock of one standard deviation would directly increase aggregate output, but its impact on output would be diminished. Compared with fiscal policy and monetary policy, the role of government spending is more likely to bring the economy into a stable state, and its response is more sensitive. We find that fiscal policy has a more significant impact on macroeconomic regulation; this suggests that monetary and fiscal policy need to work together in the context of high inflation and low interest rates. Fiscal policy drives economic recovery and can provide strong support for the realization of monetary policy.
  • Vauterin, Aleksis (2020)
    Many European citizens have growing concerns over climate change. This seems to go together with the debate about the impact of consumers’ personal dietary choices on climate change. Novel food protein sources are entering the European food market to replace or compensate meat protein sources. One protein food alternative are insect-based proteins. However, there is limited research as to how choices of alternative insect-based protein products may influence consumers’ carbon footprints. This study explores the potential of insect protein to reduce the carbon footprint associated with European food consumption. Three scenarios were formed to identify and describe options for reducing current levels of carbon footprints associated with the consumption of conventionally produced chicken meat. In the scenarios, soybean meal-based feeds used in conventional chicken production are replaced with insect-based feeds, and chicken products are replaced with protein food products from insects. Further, two different insect feeding sources are considered and compared to each other. A number of existing global warming potential values from a variety of Life Cycle Assessment studies focusing on chicken and insect production were collected to create a database for use in the scenario analyses. The database was utilised to assess the global warming impact of producing alternative insect protein on the carbon footprint of European food consumption. The results from the three scenarios indicate that the carbon footprint of food consumption can be reduced by replacing conventionally produced chicken meat with insect-based protein food products. However, insect-based protein products would have a positive impact on the carbon footprint only if the insects that are produced for use in feed or food are farmed with low-value side streams. Currently, the shift to an increased use of side streams in insect-based food production faces regulatory challenges in Europe. In the light of European efforts to encourage sustainable food alternatives, and considering the environmental benefits insects could offer as alternative proteins over options of conventional protein sources, there is a need for continued research on the environmental sustainability of insect eating and insect feeding, as well as the safety and regulatory issues related to the use of insect protein in food consumption.
  • Troullier, Marco (2022)
    One of the greatest challenges of our time is securing the global protein supply for the growing population in a sustainable manner. Fermentation with lactic acid bacteria has a long history of successful employment for the production of fermented foods and beverages. During this study, the ability of diverse lactic acid bacteria for fermentation and sensory improvement of leguminous and cereal protein concentrates was investigated.The main aim of this study was to overcome the sensory limitations of these plant protein ingredients by finding suitable candidates for the design of new starter cultures for their fermentation. A collection of 82 lactic acid bacteria was screened for fermentation of leguminous and cereal protein concentrates with different nutrient supplementations. Most strains required additional nutrients to adequately acidify the leguminous protein concentrate during a 24-h fermentation, while the cereal-based substrate appeared to be a more complete growth substrate. Descriptive sensory analysis also revealed differences in the aroma perceived by a panel depending on the matrix, supplementation and fermenting strain employed. Three of the strains that produced the most desirable aromas and acidified sufficiently the test matrixes were further studied. All three strains preferentially fermented glucose to lactic acid rather than any other sugar. The concentration of hexanal, one of the volatile compounds involved in grassy and beany off-flavor formation, reduced during fermentations in favor of 1-hexanol, a compound with a significantly higher odor threshold. However, only two of the cultures were able to prevent the growth of contaminating bacteria during fermentation. The results of this study can provide guidance for selecting potential starter cultures and fermentation substrate composition to improve the aroma of plant protein ingredients. Two of the selected strains especially have shown potential to be used as starter cultures for the leguminous protein concentrate. Further studies are required to optimize the performance of the selected strains in the test matrixes and to quantitatively characterize their effect on the substrates’ volatile profile, taste and antinutritional factor content
  • Rantonen, Elina (2021)
    Fibropapillomatoosi (FP) on maailmanlaajuisesti tunnettu merikilpikonnien kasvainsairaus. Se aiheuttaa merikilpikonnille solukuvaltaan hyvänlaatuisia sidekudoskasvaimia, jotka voivat johtaa normaalien elintoimintojen häiriintymiseen. Taudin syntyyn on aiemmissa tutkimuksissa luotettavasti yhdistetty alfaherpesviruksiin kuuluva Chelonid Herpesvirus 5 (CHHV-5), mutta taudin tarkkaa syntymekanismia ei tunneta, ja sen ilmentyminen vaatii myös muita, toistaiseksi tuntemattomia tekijöitä. CHHV-5:n uskotaan säilyvän merikilpikonnien elimistössä latentisti muiden herpesvirusten tapaan, ja sitä on havaittu useissa terveissä kudoksissa sekä FP:tä sairastavilla että terveillä eläimillä. CHHV-5:n tiedetään leviävän ainakin kasvaimista irtoavien infektoituneiden solujen kautta, mutta vasta-ainetasojen ja viruksen esiintyvyyden kartoitukset viittaisivat siihen, että on olemassa myös muita, toistaiseksi tuntemattomia tartuntatapoja. Aiemmissa tutkimuksissa liemikilpikonnien (Chelonia mydas) munuaisissa ja virtsassa on havaittu CHHV-5 DNA:ta, mikä voisi viitata viruseritykseen munuaisten kautta virtsaan. FP:tä havaitaan erityisesti nuorilla liemikilpikonnilla niiden kerääntyessä rannikkoalueille. Yhdysvalloissa Atlantin kaakkoisrannikolla samalla eläinryhmällä on havaittu rutiininomaisissa raadonavauksissa myös runsaasti alkuperältään tuntematonta munuaisytimen soluvälien sidekudostumista. Tämän tutkimuksen tavoitteena oli 1) kuvailla nämä sidekudostumismuutokset yhdistelemällä tautia ilmentäviltä eläimiltä kerättyä patologista, histopatologista ja epidemiologista tietoa, sekä 2) selvittää, voisivatko munuaisten sidekudostumismuutokset olla CHHV-5-tartuntaan liittyvä, aiemmin tunnistamaton kohde-elinvaurio. Opinnäytetyön kirjallisen osuuden on ohjannut Niina Airas ja johtanut Antti Sukura Helsingin yliopistossa. Tutkimuksen kokeelliset osuudet (qPCR-analyysi ja tilastollinen analyysi) on toteutettu Florida Atlantic Universityssä Harbor Branch Oceanographic Institutessa Annie Page-Karjianin johtamassa tutkimusryhmässä hänen ohjauksessaan. Työssä esitetyt histopatologiset tutkimukset on tehnyt Brian Stacy University of Floridassa. Floridan alueella kuolleen tai lopetetun nuoren liemikilpikonnan (62 yksilöä) munuaisten CHHV-5 DNA-kopiomäärät tutkittiin qPCR-menetelmällä, ja munuaisten sidekudostumismuutosten voimakkuus arvioitiin histopatologisesti asteikolla 1-3 (1 – lievä, 2 – kohtalainen, 3 – voimakas) kaksoissokeutetussa tutkimuksessa. Tulostemme perusteella sidekudostumismuutosten voimakkuus ei näyttäisi olevan sidoksissa liemikilpikonnien sukupuoleen, rantautumisaikaan tai kuntoluokkaan. Histopatologisiin muutoksiin ei liittynyt tulehdussolukertymiä tai havaittuja solunsisäisiä taudinaiheuttajia. Kaikilla suuremmilla kilpikonnilla muutokset olivat kohtalaisia tai voimakkaita, kun taas nuoremmilla lieviä tai kohtalaisia, mutta nämä erot eivät olleet tilastollisesti merkitseviä (Kruskal-Wallis, p=0,3). Vaikka 94%:lla (31/33) tutkituista eläimistä ei näkynyt lainkaan silminnähtäviä merkkejä sidekudostumisesta, mikroskooppisesti kohtalaista tai voimakasta munuaisten sidekudostumista havaittiin 90%lla (56/62) eläimistä. Kymmenellä (16%, 10/62) tutkituista eläimistä oli todettu FP, mutta vain viiden (8%, 5/62) eläimen munuaisessa havaittiin CHHV-5-DNA:ta. Näistä eläimistä neljällä oli fibropapillomatoosikasvaimia muualla kuin munuaisissa. Tulosten perusteella CHHV-5 ei vaikuttaisi olevan merkittävä etiologinen tekijä nuorten villien liemikilpikonnien munuaisytimen fibroosimuutoksissa Floridan alueella.
  • Rehana, Sajeda (2016)
    Development is a fundamental issue for many countries especially, developing nations. The media can play an important role in national development by connecting the government, people and development process. Thus, development journalism is one form of media function that emphasizes on advancement of living conditions of people by investigating and scrutinizing development plans, policies and actions of the government. This is why I decided to examine development issues in the media of developing country, Bangladesh. Specifically, my purpose was to explore how Bangladeshi journalists represent development issues in their media as notion of development journalism implies that it should focus on advancement of ordinary people. To conduct the research, I selected three most popular and influential newspapers (e-version) of Bangladesh in which one English and two other Bengali. These are: The Daily Star, Prothom Alo and Jugantor and the data regarding the development news stories were selected from January 2018 to June 2018. By applying mixed method, I carried out the quantitative and qualitative content analysis of development issues, for qualitative approach frame analysis was used. The study was based on the Modernization and Participatory theory of development communication and it explored representative nature of development news published by those newspapers in that period as well frequency of development news and themes in those papers. The findings revealed that development issues get little attention to the Bangladeshi media. Newspapers of this study published less than 3 percent development news in the time duration of January 2018 to June 2018 which showed a disappointing trend towards the practice of development journalism. The analysis also showed that among 13 development news themes, energy and infrastructure was the most published news topic followed by trade and business, education; on the contrary, gender equality and women empowerment, ethnic and minority rights, environmental sustainability, good governance and administrative reforms were the least preferable themes. Among three papers The Daily Star and Prothom Alo covered more diverse themes than that of Jugantor. In addition to those, development priorities exhibited in three newspapers overall reflected Bangladesh’s government development goals; however, discrepancies among them implied development journalism differ on the basis of each newspapers’ structural imperatives. Finally, this study examined the representative nature of development news in three newspapers of Bangladesh. The analysis revealed that journalists of Bangladeshi print media prefer unidirectional or modernization development communication approach (59%) in development journalism practice, it also showed a moderate portion (41%) of the representation of the participatory approach. This indicate they represent a combined approach of development communication approach with persuasive communication and Western-styled development model along with acknowledging the general peoples’ view although the participatory portion is not satisfactory to the expectation level of development journalism practice.
  • Ziyu, Xing (2022)
    This thesis is aimed to investigate the long-run and short-run relationship between renewable, nuclear energy consumption, economic growth and CO2 emissions in Finland. The historic development and current situations of the energy consumption, economic growth and CO2 emissions are discussed. Then Johansen cointegration test and Vector Error Correction Model (VECM) are applied in the empirical analysis to further exploit the causal relationships between the variables. There are four variable employed in this thesis: renewable energy consumption (REC), nuclear energy consumption (NUC), Gross Domestic Product (GDP) and CO2 emissions (COE). The data of the variables span from 1977 to 2020 and mainly come from official databases and reports from the Finnish government and international organizations, such as Statistics Finland, Our World in Data, World Bank, etc. The results indicate that there is the positive bidirectional long-run relationships between NUC, REC and GDP. Also, the unidirectional long-run relationships of GDP, REC, NUC with COE are estimated. The increase in GDP and NUC are estimated to increase COE in the long run, while REC is estimated to decrease COE. Furthermore, the negative short-run relationships between REC, NUC and COE are found, which shows that, in the short run, renewable and nuclear energy consumption in Finland is estimated to reduce the CO2 emissions. The findings from the thesis indicate renewable energy consumption is both economic and environmental-friendly. Nuclear energy is also good for economic growth in the long run and environment in the short run, but needs to be cautiously treated with regard to environmental protection in the long-run strategies. Also, there has been the trend of impact decoupling in Finland in the short term. However, further research is needed to test the EKC hypothesis and its turning point.
  • Mattila, Saku (2023)
    Plants are vital to all terrestrial ecosystems by providing ecosystem services through photosynthesis- derived compounds. Throughout the millennia, plant metabolism has diversified in the form of all plant secondary metabolites, ranging from metabolite groups such as terpenes to alkaloids to flavonoids. Many of these secondary metabolites are economically valued for their chemical, pharmaceutical and physical properties. The flavonoids are one of the largest groups and are known to provide competitional advantages and increase of survival of many plant species in extreme environments. One of the critical enzymes in the whole biosynthesis pathway of flavonoids is the dihydroflavonol 4- reductase (DFR). DFR regulates the formation of leucoanthocyanidins, predecessors of colourful anthocyanins. Anthocyanins are an economically significant group of molecules, especially for horticulturists and plant breeders, but also for nutritional and health scientists due to their potential health benefits. Dihydroflavonol 4-reductase is a much-studied enzyme due to its significant role in flavonoid biosynthesis and the economic interests of plant breeders and alike. Previous studies have expanded the knowledge of flavonoid biosynthesis and have identified several amino acid residues in the DFR structure affecting the substrate specificity of the enzyme and, consequently, the flower colours. However, only a single crystal structure model of the dihydroflavonol 4-reductase has been solved so far, originating from the grapevine Vitis vinifera. Although a single crystal structure can facilitate further structure-to-function studies associated with dihydroflavonol 4-reductase, further studies need to be carried out to shine a light on the functional basis of the enzyme. Therefore, this study aims to resolve petunia and gerbera dihydroflavonol 4-reductase crystal structures, expanding the knowledge of structural variations within the uncharted families of angiosperms, Solanaceae and Asteraceae. Several recombinant protein expression systems were utilised in my attempts to solve the crystal structure of the DFRs. These systems ranged from the bacterium Escherichia coli to yeast species such as Saccharomyces cerevisiae and Pichia pastoris, as well as the tobacco plant Nicotiana benthamiana. The genes encoding for Petunia wildtype DFRA, three mutants, and three Gerbera DFR variants were cloned to several expression vectors. Their presence and expression were identified using various genetic methodologies and enzymological assays. The expression of DFRs using an E. coli-based expression system was verified. However, the trials with E. coli were deemed unsuccessful due to the majority of the protein ending in inclusion bodies with no detectable activity. An alternative system using agroinfiltration of N. benthamiana was later utilised, as significant amounts were detected in the plant tissue extracts following the agrobacterial infiltration. Although the proteins were expressed in high quantities, no purification procedures have been established to provide plant tissue-extracted protein in crystallography-grade purity. With the protein supplied by a plant-based system and several small- scale purification steps, purified DFR enzymes could be utilised in crystallisation studies. Due to significant contamination by RuBisCO in the protein samples, alternative systems based on S. cerevisiae and Pichia pastoris were investigated, and a successful Pichia-based expression was established. Several sets of plasmids with variable expression systems were constructed in this study, facilitating future experiments into the dynamics and structure of dihydroflavonol 4-reductases. Ground-breaking techniques based on computational modelling were utilised to hypothesise the role of prior determined amino acid residues in enzyme catalysis and substrate recognition. Possible crystallisation-related issues originating from protein structure were approached using the same techniques, opening new windows and possibilities into determining the structure of Petunia hybrida and Gerbera hybrida dihydroflavonol 4-reductase structures using tools of protein engineering.
  • Korhonen, Keijo (2022)
    The variational quantum eigensolver (VQE) is one of the most promising proposals for a hybrid quantum-classical algorithm made to take advantage of near-term quantum computers. With the VQE it is possible to find ground state properties of various of molecules, a task which many classical algorithms have been developed for, but either become too inaccurate or too resource-intensive especially for so called strongly correlated problems. The advantage of the VQE comes in the ability of a quantum computer to represent a complex system with fewer so-called qubits than a classical computer would with bits, thus making the simulation of large molecules possible. One of the major bottlenecks for the VQE to become viable for simulating large molecules however, is the scaling of the number of measurements necessary to estimate expectation values of operators. Numerous solutions have been proposed including the use of adaptive informationally complete positive operator-valued measures (IC-POVMs) by García-Pérez et al. (2021). Adaptive IC-POVMs have shown to improve the precision of estimations of expectation values on quantum computers with better scaling in the number of measurements compared to existing methods. The use of these adaptive IC-POVMs in a VQE allows for more precise energy estimations and additional expectation value estimations of separate operators without any further overhead on the quantum computer. We show that this approach improves upon existing measurement schemes and adds a layer of flexibility, as IC-POVMs represent a form of generalized measurements. In addition to a naive implementation of using IC-POVMs as part of the energy estimations in the VQE, we propose techniques to reduce the number of measurements by adapting the number of measurements necessary for a given energy estimation or through the estimation of the operator variance for a Hamiltonian. We present results for simulations using the former technique, showing that we are able to reduce the number of measurements while retaining the improvement in the measurement precision obtained from IC-POVMs.
  • Huhtala, Niko (2021)
    This MA thesis explores the use of English on Instagram in the Finnish capital region that consists of the municipalities of Helsinki, Vantaa, Espoo and Kauniainen. Building on previous research on Virtual Linguistic Landscapes and English as a lingua franca, this thesis investigates the extent to which English is used in the study area and how different types of areas and locations differ in terms of English use in the study area. For this purpose, I use geotagged social media data and methods from the fields of natural language processing and geoinformatics. Firstly, I analyse the general linguistic make-up of the study area to understand the use of English in relation to other languages. Secondly, I analyse and compare how the use of English and Finnish are spread geographically across the Finnish capital region on Instagram and identify spatial clusters by means of spatial autocorrelation analysis. Lastly, I seek to provide further insights into the different types of locations where English, Finnish and other languages are used by using the Corine Land Cover inventory for categorising different types of locations. The results of this study show that the English language has a very strong presence as the second most used language in the Virtual Linguistic Landscape of the Finnish capital region. English is used especially often by users who use more than one language on Instagram. The spatial patterns of English use show that the language is used particularly often in the Helsinki city centre, western Helsinki and eastern Espoo and least in north-eastern Helsinki and Vantaa. English has a strong presence in essentially all the studied location types, especially in commercial and urban contexts. The relative proportions of English use are highest at airport areas and lowest in various sport and leisure facilities, where Finnish is used significantly more than any other language. In the analysis, I also include frequent observations on Finnish and other languages, which provide further insights into the rich Virtual Linguistic Landscape of the capital city region.
  • Silvennoinen, Meeri (2022)
    Malaria is a major cause of human mortality, morbidity, and economic loss. P. falciparum is one of six Plasmodium species that cause malaria and is widespread in sub-Saharan Africa. Many of the currently used drugs for malaria have become less effective, have adverse effects, and are highly expensive, so new ones are needed. mPPases are membrane integral pyrophosphatases that are found in the vacuolar membranes of protozoa but not in humans. These enzymes pump sodium ions and/or protons across the membrane and are crucial for parasite survival and proliferation. This makes them promising targets for new drug development. In this study we aimed to identify and characterize transient pockets in mPPases that could offer suitable ligand binding sites. P. falciparum was chosen because of its therapeutical interest, and T. maritima and V. radiata were chosen because they are test systems in compound discovery. The research was performed using molecular modelling techniques, mainly homology modelling, molecular dynamics, and docking. mPPases from three species were used to make five different systems: P. falciparum (apo closed conformation), T. maritima (apo open, open with ligand, and apo closed) and V. radiata (open with ligand). P. falciparum mPPase does not have a 3D structure available, so a homology model was built using the closest structure available from V. radiata mPPase as a template. Runs of 100 ns molecular dynamics simulations were conducted for these five systems: monomeric mPPase from P. falciparum and dimeric mPPases for the others. Two representative 3D structures for each of the five trajectories, the most dissimilar one to another, were selected for further analysis using clustering. The scrutinized 3D structures were first analyzed to identify possible binding pockets using two independent methods, SiteMap and blind docking (where no pre-determined cavity is set for docking). A second set of experiments using different scores (druggability, enclosure, exposure, …) and targeted docking were then run to characterize all the located pockets. As a result, only half of the catalytic pockets were identified. None of the transient pockets were identified in P. falciparum mPPase and all of them were located within the membrane. Docking was performed using compounds that have shown inhibiting behavior in previous studies but did not give good results in the tested structures. In the end none of the transient pockets were interesting for further study.
  • Palo-oja, Peter (2018)
    Developmental dyslexia (DD) affects the accuracy and the fluency of reading without influencing the intelligence of an individual. Problems in phonological awareness (PA), the ability to manipulate the sound structure of words, has been proposed to be the key predictor of DD across languages. Diffusion tensor imaging (DTI) has been used to investigate white matter (WM) structure in DD. The DTI research has concentrated mainly on fractional anisotropy (FA) values, that measure the integrity of WM, and volume of the WM tracts, but also on lateralization differences. Structural alterations have been reported in multiple WM tracts, but left arcuate fasciculus (AF) have most consistently been associated with problems in phonological processing. Also, individuals with DD have been reported to have less prominent leftward lateralization in AF, and inferior fronto-occipital fasciculus (IFOF) compared to non-DD individuals. The participants consisted of 23 individuals with confirmed DD and 21 without DD. In this thesis the reading-related WM tracts were evaluated using deterministic tractography, and the goal was to 1) compare DD and non-DD participants in the FA and volume in reading circuitry, 2) study the associations between reading skills and FA and volume of the WM tracts, and 3) study the lateralization differences in FA and volume. The results of this thesis did not support the current view of the neuroanatomy of DD. Although groups did not differ in FA or in volume of the reading related WM tracts, the groups differed in the lateralization of the WM tracts. Both DD and non-DD participants manifested a rightward lateralization of WM volume in the AF, opposing the earlier findings. Furthermore, DD participants had a unique rightward lateralization of volume in uncinate fasciculus. Subthreshold results in correlations between reading skills and DTI indices also hint toward the heterogeneity found in the DTI research of DD, and do not confirm the role of the AF as the neural correlate of the phonological processing. It seems that no single abnormality in WM structure is responsible of DD. Rather, it seems that DD compiles a vast spectrum of symptoms, with possibly multiple trajectories, and individual compensatory mechanisms in adult samples.
  • Koskinen, Anssi (2020)
    The applied mathematical field of inverse problems studies how to recover unknown function from a set of possibly incomplete and noisy observations. One example of real-life inverse problem is image destriping, which is the process of removing stripes from images. The stripe noise is a very common phenomenon in various of fields such as satellite remote sensing or in dental x-ray imaging. In this thesis we study methods to remove the stripe noise from dental x-ray images. The stripes in the images are consequence of the geometry of our measurement and the sensor. In the x-ray imaging, the x-rays are sent on certain intensity through the measurable object and then the remaining intensity is measured using the x-ray detector. The detectors used in this thesis convert the remaining x-rays directly into electrical signals, which are then measured and finally processed into an image. We notice that the gained values behave according to an exponential model and use this knowledge to transform this into a nonlinear fitting problem. We study two linearization methods and three iterative methods. We examine the performance of the correction algorithms with both simulated and real stripe images. The results of the experiments show that although some of the fitting methods give better results in the least squares sense, the exponential prior leaves some visible line artefacts. This suggests that the methods can be further improved by applying suitable regularization method. We believe that this study is a good baseline for a better correction method.
  • Merikoski, Jori (2016)
    We study growth estimates for the Riemann zeta function on the critical strip and their implications to the distribution of prime numbers. In particular, we use the growth estimates to prove the Hoheisel-Ingham Theorem, which gives an upper bound for the difference between consecutive prime numbers. We also investigate the distribution of prime pairs, in connection which we offer original ideas. The Riemann zeta function is defined as ζ(s) := \sum_{n =1}^{∞} n^{-s} in the half-plane Re s > 1. We extend it to a meromorphic function on the whole plane with a simple pole at s=1, and show that it satisfies the functional equation. We discuss two methods, van der Corput's and Vinogradov's, to give upper bounds for the growth of the zeta function on the critical strip 0 ≤ Re s ≤ 1. Both of these are based on the observation that ζ(s) is well approximated on the critical strip by a finite exponential sum \sum_{n =1}^{T} n^{-s} = \sum_{n =1}^{T} exp\{ -s log n \}. Van der Corput's method uses the Poisson summation formula to transform this sum into a sum of integrals, which can be easily estimated. This yields the estimate ζ(1/2 + it) = \mathcal{O} (t^{\frac{1}{6}} log t), as t → ∞. Vinogradov's method transforms the problem of estimating an exponential sum into a combinatorial problem. It is needed to give a strong bound for the growth of the zeta function near the vertical line Re s = 1. We use complex analysis to prove the Hoheisel-Ingham Theorem, which states that if ζ(1/2 + it) = \mathcal{O} (t^{c}) for some constant c > 0, then for any θ > \frac{1+4c}{2+4c}, and for any function x^{θ} << h(x) << x, we have ψ (x+h) - ψ (x) ∼ h, as x → ∞. The proof of this relies heavily on the growth estimate obtained by the Vinogradov's method. Here ψ(x) := \sum_{n ≤ x} Λ (n) = \sum_{p^k ≤ x} log p is the summatory function of the von Mangoldt's function. From this we obtain by using van der Corput's estimate that the difference between consecutive primes satisfies p_{n+1} - p_{n} < p_{n}^{\frac{5}{8} + \epsilon} for all large enough n, and for any \epsilon > 0. Finally, we study prime pairs, and the Hardy-Littlewood Conjecture on their distribution. More precisely, let π _{2k}(x) stand for the number of prime numbers p ≤ x such that p+2k is also a prime. The following ideas are all original contributions of this thesis: We show that the average of π _{2k}(x) over 2k ≤ x^{θ} is exactly what is expected by the Hardy-Littlewood Conjecture. Here we can choose θ > \frac{1+4c}{2+4c} as above. We also give a lower bound of π _{2k}(x) for the averages over much smaller intervals 2k ≤ E log x, and give interpretations of our results using the concept of equidistribution. In addition, we study prime pairs by using the discrete Fourier transform. We express the function π _{2k}(n) as an exponential sum, and extract from this sum the term predicted by the Hardy-Littlewood Conjecture. This is interpreted as a discrete analog of the method of major and minor arcs, which is often used to tackle problems of additive number theory.
  • Nguemgne Fotso, Rostandine (2019)
    Cameroon is a country located in Central Africa. The country has an export-led economy, which means that the country highly depends on exports to ensure its population well-being. Sawnwood exports represent 14% of Cameroon’s total exports. Sawnwood is therefore one of the most important export products for Cameroon. Since Cameroon signed the EU-Cameroon voluntary partnership agreement policy in 2010, Cameroon’s sawnwood exports were impacted. The aim of this study is therefore, to examine the export competitive performance of Cameroon’s sawnwood industry from 2001 to 2017. Based on the literature, a set of three methods analyzing the competitiveness of Cameroon’s sawnwood exports were chosen. These methods are: The Revealed Comparative Advantage Index (RCA) and RSCA index which were used to analyze the competitiveness and international specialization of Cameroon in exporting sawnwood. The Spearman Rank Correlation was used to study the export competitive performance of Cameroon’s sawnwood across years and to analyze the level of competition between Cameroon, Finland, China and Ghana. Lastly, the Constant Market Share Analysis was used to explain the drivers of Cameroon’s sawnwood export competitiveness. This study also compiles information on forest in Cameroon and provides an overview of Cameroon sawnwood industry, it can therefore serve as a base for further studies on sawnwood in Cameroon. Results show that Cameroon has a competitive advantage and is the highest specialized in exporting sawnwood compared to Finland, China and Ghana. Nevertheless, the export competitive performance of Cameroon across years is not continuous and highly depends on external factors. Results also show that Cameroon has reduced its exports to EU and has diversified its importers portfolio by redirecting its exports trade flows towards Asia, especially China which has less stringent imports policies compared to EU. Cameroon will need to improve its production technologies and management practices to ensure a long run competitiveness on the global sawnwood market.