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  • Lahin, Tuuli (2023)
    Due to population growth, urbanization, and increase in life expectancy, the urban population is growing, and by 2050 68% of the global population is expected to live in urban areas. Even though the air quality in urban settings has greatly improved in recent decades due to increased legislation, restriction, and monitoring, the negative health impacts associated with pollutants have not completely diminished. Air quality varies on a local scale due to urban form and function, that creates differences in experienced exposure among individuals. These exposure differences among socio-economic groups have been studied, but no clear consensus has been found, as the results have been very diverse and even contradictory. Therefore, conducting local level studies is important in order to identify local patterns of exposure and to recognize them in urban planning. However, previous literature on the topic in Finnish context is lacking. This thesis studies interpolated air pollutant exposure among one susceptible socio-economic group – the elderly – and aims to identify possible hotspots of both in Helsinki, Finland. The distribution of the elderly and air quality is assessed through Moran’s I calculations. Global Moran’s I is used to assess for spatial autocorrelation, and local Moran’s I is applied to identify local clusters. To further examine the relationship, correlation coefficients are calculated through Spearman’s rank correlation coefficient. According to the results, there is a weak positive correlation between the elderly and air quality, indicating that generally air quality tends to be worse when the number of elderly people increase. However, the relationship is stronger among younger age groups, although the differences between age groups is very small. The exposure was also assessed through overlapping high value clusters, which indicate that elderly clusters in the city center are located in areas with low air quality, while elderly clusters in Lauttasaari and Vuosaari are located in areas with good air quality. Previous studies regarding the relationship between age and air pollution exposure have been contradicting in different cities, and therefore these results provide important knowledge about the problem specifically in the context of Helsinki. Additionally, the results are be observed in the light of the larger discourse around socio-economic status and air pollution, but further studies on the topic are still needed. Including multiple socio-economic variables and the dimension of negative health outcomes would aid in identifying 1) the most important socio-economic factors in the context of negative health outcomes associated with air pollution, and 2) those areas where multiple important socio-economic factors and low air quality are overlapping and therefore might have higher risk for negative health outcomes.
  • Lewis, Serena (2021)
    Histamine receptors are known to be expressed throughout the peripheral nervous system and are involved in regulating the gut and immune system. The gut-brain axis, which consists of bidirectional signaling between the central nervous system and gastrointestinal tract, links gut functions to emotional and cognitive controls in the brain. Many animal models are known to express histamine receptors in their gut and brain tissue which can be altered by a compromised gut-brain axis like stress. Histamine receptors also play an important role in many gastric and intestinal disorders. However, the precise expression pattern of histamine receptors in zebrafish gut tissue is unknown, as is whether their expression levels also change with stress. Here, I show that zebrafish gut contains several histamine receptors, but their role involving stress within the gut remains unknown. I found that histamine receptors hrh1 and hrh3 as well as the enzyme that synthesizes histamine, histidine decarboxylase (hdc), are expressed in zebrafish gut and brain in wildtype and hdc knockout adult zebrafish using in situ hybridization. Stress induction on wildtype male zebrafish through chronic social defeat and analysis of histamine receptor and hdc mRNA levels using quantitative real time PCR showed no differences in subordinate, dominate, or control fish. However, it did provide quantitative data that hrh1, hrh2, and hdc mRNA expresses in the adult gut. My results demonstrate the first data to suggest histamine receptors are expressed in zebrafish gut, and that even though stress can alter the gut-brain axis, it may not do so through the regulation of these receptors.
  • Taha, Lamia (2021)
    The endoplasmic reticulum (ER) is an important organelle of the cell where a high number of proteins are synthesized and modified to obtain their final structure. Therefore, the ER stress, which is caused by accumulation of unfolded proteins in the ER, is not to be taken lightly since it could contribute to many diseases, such as cancer and neurodegenerative diseases. The response to the ER stress is the unfolded protein response (UPR), which is an adaptive system that helps in adjusting for increased folding needs within the ER. One of the main protein branches in the UPR is inositol requiring enzyme 1 (IRE1). IRE1 detects the status of protein folding inside the ER and initiates the UPR signaling pathway to achieve either normal folding status or cell death. The aim of this research was to express yeast IRE1 in E.coli and human IRE1 in insect cells, purify with affinity chromatography and study the IRE1’s crystal structure with a small molecule modulator that could possibly enhance its activity. The protein was expressed successfully and purified with glutathione S-transferase (GST) tag, and the activity of the pure protein was determined. The structural studies were not fully completed since the absolute purity and yield that was necessary for crystallization was not achieved due to loss of protein during gel filtration and precipitation. Based on the results it is likely that the structure of the protein could be solved and further biochemical and structural studies with F10 are possible.
  • Knapič, Samanta (2023)
    White matter (WM) structural connectivity alterations have been linked to depression. This study aimed to identify structural connectivity metrics associated with Major depressive disorder (MDD) and predictive of different symptom phenotypes. The study sample included N=29 control and N=86 subjects with MDD who underwent a clinical interview, Mini-International Neuropsychiatric Interview (MINI), and assessment of depression symptoms severity. Using a 3T MRI scanner, diffusion tensor imaging (DTI) was employed to capture WM connectivity markers at baseline. While no distinct differences between control and MDD groups were observed at the whole-brain network level, significant alterations were evident at the node level. Clinical group demonstrated enhanced connectivity, particularly in the DefaultB and LimbicB subsystems, as evidenced by measures such as eigenvector centrality. Furthermore, notable differences were observed in clustering coefficient and local efficiency, predominantly in DefaultB, LimbicB, and VisPeri networks, with MDD patients showing higher connectivity. Analysis of the association between WM structural connectivity measures, both global (e.g. global efficiency) and local (e.g. clustering coefficient) with MDD symptom scores and related symptoms, revealed no significant correlation at the whole-brain level, both at baseline and post-intervention. Distinct patterns were identified when evaluating node-level metrics averaged across networks, which together with group differences, point to MDD patients exhibiting characteristics consistent with regular networks. Hierarchical clustering based on standardized baseline DTI structural connectivity within the clinical cohort revealed three distinct clusters of MDD patients, with the first cluster exhibiting a higher WHO-5 score, indicating a potential association with better well-being. These findings provide insight into MDD-specific brain regions’ structural alterations and underscore the heterogeneity of depression symptom profiles. Further research is needed, including a higher sample size and control for confounding factors.
  • Berglund, Nora (2022)
    In Finland and in many other European countries, indoor housing of dairy cattle has been increasing at the expense of grazing. According to Finnish legislation, only dairy cows housed in tie-stalls are obligated to graze for 60 days per year between May and September. Pressure to intensify production leads to increase in herd sizes, regional concentration, lack of suitable pastureland near large barns, and automation of milking. Conversely, grazing is regarded as important for animal welfare, maintenance of biodiversity and cultural landscapes. Farmer perceptions towards grazing have not been studied in Finland comprehensively, which need to be understood better in order to provide adequate support for sustainable management of grazing. The research aims at gaining understanding of the external and internal factors driv- ing the farm-level decision making related to grazing regimes. Concept of good farming ideal is used to examine farmers’ decision-making. The data was collected from 26 cattle farms with a gradient of grazing from zero to maximum. Firstly, an online questionnaire was sent out to farmers and secondly, semi-structured inter- views were conducted with 7 dairy producers, to further explore farmer views about grazing, biodiversity, and animal welfare. The results show farmers who practice grazing to perceive it more positively than the farmers who do not graze. Some of the farmers who grazed seemed to consider it almost as an intrinsic value, whereas farmers with no grazing saw it as an inef- ficient production method, which they were afraid would become an obligation. The most im- portant internal factors driving decision-making about grazing based on the questionnaire and interviews, were animal welfare, decreased workload because of grazing, infrastructure of the farm, economic aspects, and benefits of grazing to biodiversity and landscape values. Exter- nal factors found to affect the decision of grazing were incentives, regulations, and consumer expectations. Animal welfare was found to be a basis for production for many and the most important feature valued for good farming, to which grazing was seen to contribute. The re- sults imply subsidies regarding grazing should be higher for grazing to be considered profita- ble and more enjoyable by farmers.
  • Heilala, Maria (2019)
    Despite the advances in the management of breast cancer, discovery of novel and targeted drugs remains a challenge. It has been suggested that drug failure rates in clinical trials might be diminished by improving the predictive potential of preclinical cancer models. Three-dimensional (3D) scaffold-based cell culture has emerged as an attractive platform for mimicking tissue-like microenvironment, since it is well-known that cells respond to the cues in the extracellular matrix (ECM). The aim of this thesis was to develop fibrin-based hydrogels and evaluate their performance in 3D cell culture of breast cancer cells. The fibrin gel formulation was first optimized by testing the effect of different buffers on gel properties. Structural properties were examined with scanning electron microscopy and mechanical properties measured with oscillatory rheometry. Three different fibrin concentrations of the optimized formulation were then used as scaffolds for DU4475 breast cancer cells. After seven days of culture, the morphology, phenotype and proliferation of the resulting cell structures were assessed by using techniques such as light microscopy, immunofluorescent confocal microscopy and Western blot analysis. The desired properties for 3D cell culture were obtained by preparing fibrin gels at high pH in the absence of calcium. The main finding of the thesis was that fibrin concentration strongly affected the phenotype of DU4475 cells, with cells cultured in the softest gel retaining their original characteristics to the greatest extent. In the future, the developed scaffold could possibly be used in drug discovery and personalized medicine by culturing tumor explants from patients. However, the methods used in the study must be further optimized and the results validated with other breast cancer cell lines and with primary tissues.
  • Katajarinne, Jenni (2022)
    Biodiversity loss and ecosystem service degradation and the related economic costs are increasingly recognized as sources of financial risks. The risks are arising through physical and transition sources of risks caused by dependencies and impacts upon biodiversity and ecosystem services. Therefore, it has become increasingly important for both individual financial institutions as well as central banks and financial supervisors to better understand and manage these risks. However, biodiversity loss is associated with unique complexity and uncertainty, making it a challenging task. The purpose of this thesis was to study the linkages between biodiversity loss and financial stability in Finland. This was done by assessing the financial exposure of Finnish credit institutions to sectors dependent on ecosystem services for their production processes. A quantitative analysis was conducted in order to combine loan data obtained from the Bank of Finland and ecosystem service data obtained from the ENCORE database. The results showed that 23% of loans provided by Finnish credit institutions are exposed to high or very high biodiversity-related financial risks. The sectors associated with most value at risks were real estate and agriculture, forestry and fishing sectors. Disruptions of ecosystem services providing surface water and climate regulation were posing the highest financial risks. The findings represent a first step towards assessing the exposure of the Finnish financial system to biodiversity-related financial risks. The results and previous literature indicate that physical biodiversity-related financial risk exposures are significant for individual financial institutions and for the whole financial system, despite the prevailing methodological challenges and gaps in knowledge. In order to complete a comprehensive biodiversity-related financial risk assessment, further research is needed.
  • Väyrynen, Pia (2017)
    Follicle-stimulating hormone (FSH) regulates mammalian reproduction. The hormonal function of FSH is exerted through its receptor, FSHR. Hormone binding leads to signal transduction by the synthesis of the second messenger (intracellular cAMP) and the activation of other downstream signaling pathways. FSH receptors are mainly found in ovaries and testes where FSH stimulates e.g. follicular growth and spermatogenesis, respectively. It has been previously shown that FSHR mutations are linked to infertility through abnormalities in the receptor function. For example, inactivating FSHR mutation (Ala189Val) leads to arrest of follicular development in females and reduced sperm counts in males. FSH action seems to be especially critical for folliculogenesis and essential for female fertility. The development of gonads and dysfunctions affecting reproduction are the focus of our research group. Studies of recent years have demonstrated extragonadal FSHR expression, including endothelial cells of female reproductive tract and developing placenta. The physiological relevance and function of this extragonadal FSHR is still not well known, especially during embryogenesis. In addition, the expression or function of the mutated FSHR has not been studied in any cells endogenously expressing the receptor. As a consequence, the purpose of this thesis was to study FSHR expression and function in human pluripotent stem cells (hPSCs) as a model for early human development. The study was conducted in a human embryonic stem cell line (hESC H9, 46, XX) and two human induced pluripotent stem cell lines (hiPSC HEL127.6 and HEL128.5; 46, XX). iPSCs were obtained from female patients carrying the A189V mutation in the FSHR gene. Cells were differentiated for 8/12 days using two in vitro cell culturing protocols for distinct differentiation attempts. The first protocol (protocol D) was designed for embryonal cell differentiation, the other (trophoblast protocol) for extraembryonal differentiation. Cells at different stages of differentiation were studied with qRT-PCR and immunocytochemistry. At d8, cells were stimulated with FSH for qPCR studies and for cAMP assay. Control cells (H9) differentiated by protocol D endogenously expressed functional FSHR. These cells responded dose-dependently to FSH stimulation by substantially increasing cAMP production, downregulating FSHR mRNA expression and altering inhibin gene expression. Patient-derived iPSCs carrying the mutation expressed FSHR as well but the receptors were non-functional as expected. Both H9 and patient-derived cells that differentiated into trophoblast-like cells with the other protocol, also expressed FSHR at low level but did not respond to FSH stimulation. Preliminary results with protocol D indicate that the cells resemble extraembryonic cell types. The study has revealed novel information and insight about extragonadal FSHR expression and function during differentiation. However, the exact identity and the biological role of these cells is yet to be confirmed.
  • Aapio, Fanny (2020)
    Food literacy is a noteworthy topic to be studied due to food’s considerable environmental and health effects. When food literacy and its characteristics are known, food literacy can be used as a tool to improve people’s health and the condition of the environment. Thus, this thesis aims to reveal the extent of food literacy among Finnish upper secondary school students. In this context, food literacy emphasises food-related environmental and health knowledge. Environmental knowledge is understanding of the global environmental impact of food. Health knowledge, on the other hand, is the familiarity with the relationship between excessive meat consumption and Finnish common diseases along with beliefs regarding diets and food products as a source of protein. This thesis also aims to identify to what extent does the food literacy differ based on gender, study year and living area. This study was performed as a quantitative sample survey and the data was collected using an online Typeform -questionnaire. The questionnaire reached respondents from many different Finnish localities, mainly from cities. The final data consisted of 1320 individuals and it was analysed using IMB SPSS Statistics 24 software. The following methods were used to analyse data: frequency analysis, an Independent Samples t Test, a One-way ANOVA, and a Post-hoc LSD test. Gender, study year and living area were used as grouping variables to examine the differences between groups. The results show that the students named school as the main source of food literacy. Moreover, the results indicate that awareness regarding food production, dietary health and proteins increase significantly from the first to the third study year. The students acknowledged food production causing environmental problems and that the share of food in the consumer’s climatic impact is considerable. Nevertheless, the students underestimated the climatic impact of cheese and they were unaware of the more specific characteristics of food’s environmental impacts. They also had food-related environmental misconceptions considering packaging, transportation and meat consumption. Moreover, approximately half or more of the students were aware of the connection between excessive meat consumption and the increased risk of distinct common diseases. Most of the students acknowledged a versatile vegetarian diet as being a healthy choice. The study also reveals that female students had notably higher dietary health knowledge than male students. This Master’s thesis study mainly supports the findings of previous studies on food-related knowledge. The results elucidate the extent, characteristics, gaps and misconceptions of students’ food literacy. These findings may be utilized to improve school education on food literacy, alter misconceptions and fill the gaps of knowledge in pursuit of improving the health of people and the condition of the environment.
  • Jokinen, Toni (2019)
    In this thesis I focus on a novel disaster response and preparedness mechanism called forecast-based financing. The mechanism is linked to the changing paradigm of humanitarian response that calls for more localized and more resilience building solutions to addressing and preventing humanitarian crisis. It is also in the core of the anticipation agenda which argues that waiting for disasters to happen is not a sustainable option and that forecast data and pre-agreed triggers and actions should be used in order to prevent both loss of lives and mitigate the cost and impact of disasters. Main hypothesis is that climate related hazards to livelihoods and food security seems to be the sector where forecast-based financing could have most potential for increasing resilience and sustainability. Slow onset crises with long lead-time allow for better targeting and more variety of actions. As the lifetime of the action is longer, there is less chance of action which is in vain. Furthermore, the actions which are more localized, for example direct support to farmers, can decrease their vulnerabilities. I aim at taking a critical approach to assessing this potentiality associated with the forecast-based financing mechanism through case study. The three cases (Mongolia, Kenya, Zimbabwe) were selected from pilots implemented by the main actors: the Red Cross, World Food Programme (WFP) and Food and Agriculture Organization (FAO) and Start Network. This thesis uses a combination of evaluative and heuristic approach to qualitative case study analysis. To answer the first research question, 1) is the forecast-based financing mechanism successful in prioritization of actions in a way that best address the needs and resources of vulnerable populations, I aim at finding out if mechanism is effective (or potentially effective) in delivering impact. For the second research question, 2) are the actions sustainable and do they bring socio-economic benefits that go beyond meeting acute humanitarian needs, I will see if new pathways are found for confirming the defined hypothesis. I am using heuristic approach in terms of finding new links e.g. between actions and needs of either donors, actors or beneficiaries. I asses and analyse available reports and evaluations (secondary data) of the selected operations. I conducted eleven (11) semi-structured key informant interviews (primary data) using practitioner’s perspective for retrieving qualitative data, for further understanding and for triangulation. All key informants were affiliated to the cases. My analysis show that the potentiality for development impacts and long-term transformation of the forecast-based financing is there but it is not utilized in the cases reviewed nor is it perceived in a same way across practitioners of different backgrounds. Currently the mechanism is used more for effective response, not for addressing the root causes of vulnerability. In general, the entitlement or empowering of a person who is affected by disaster currently does not go beyond securing bridge over lean season, avoiding negative coping mechanisms or e.g. better yield or survival of livestock. Sustainability potential of the forecast-based financing seems to be currently underutilized and international funding envelopes do not offer an alternative to the humanitarian funding launched case-by-case. Most of the practitioners interviewed were clearly in favour of linking and using forecast-based financing in some way to long-term programming, thinking outside of the framework of humanitarian response, extending lead time significantly and adding positive reinforcement inputs. I argue that with a lead time that goes long in advance, towards development actions, the mechanism needs to be reframed for the donors and the sources of funding might need to be reconsidered. To implement meaningful resilience actions in slow onset cases, triggers need to be early enough and actions in two phases: 1) anticipatory and benefiting from forecast and 2) early response. At beneficiary level the actions should be geared up to better address underlying socio-economic vulnerabilities and take advantage of the long lead time.
  • Raitanen, Henna (2020)
    In this study, the goal was to determine which nutrient, phosphorus or nitrogen, limits the phytoplankton growth at the Vanajavesi freshwater site. The aims were to detect spatial and temporal changes and find out if the wastewater treatment plant (hereafter, WWTP) located by the study site affects the nutrient concentrations and the limiting nutrient. The reliability of determining limiting nutrient by bioassays and measuring the phytoplankton response to different treatments as fluorescence was also evaluated. The study was conducted because knowledge of nutrient limitation is essential when allocating resources to reduce nutrient loading and planning other remediation practices in eutrophicated waterbodies. According to the EU Water Framework Directive, all waterbodies in the EU must be in a good ecological status by the year 2027. This goal is yet to be achieved in Vanajavesi; the ecological status of the river Vanajanreitti is poor and that of lake Vanajanselkä is moderate. The samples for bioassays were taken from five different locations. Three sampling sites were in the river and two by the lake. Based on the direction which the water flows, one of the sampling sites was before the outlet from the WWTP and the rest after it. The bioassays were carried out with the water and natural phytoplankton community taken from the study site. The experiment was conducted five times: in November, March, May, July and August. The temperature and light conditions in the incubation room were set to mimic those in Vanajavesi at each given time. Part of the preparations was to filter out the zooplankton using 50 μm plankton net. There were four different treatments: control without nutrient additions, nitrogen addition, phosphorus addition and nitrogen and phosphorus additions. Fluorescence from the 2 litre incubation bottles was measured every 1-3 days during each experiment. Chlorophyll a was determined in laboratory before and after the experiments. Nutrient concentrations were also determined before each experiment. Small seasonal and temporal changes were observed in the nutrient concentrations and the limiting nutrient. These changes were most likely due to changing seasons, effluent from the WWTP and denitrification at lake Vanajanselkä. Phosphorus limited phytoplankton growth year around at all places. At the end of the summer also nitrogen was limiting. In July co-limitation was detected in all sampling sites. In situations of co-limitation there was either no secondary limiting nutrient, or it was phosphorus. Only once, in August at the sampling point before the outlet from the WWTP, was the secondary limiting nutrient nitrogen. On average the nutrient concentrations were higher in the river than in the lake. Chlorophyll a concentrations and some nutrient concentrations were higher after the WWTP. However, no significant negative impact due to WWTP could be detected, especially at lake Vanajanselkä and the WWTP did not result in a change from phosphorus limitation to nitrogen limitation. Bioassays and the phytoplankton yield measured with a fluorometer was a reliable way of determining the limiting nutrient. Chlorophyll a concentrations verified the fluorescence results. The probe used in this study measured only the fluorescence of chlorophyll a. Even more accurate result of the phytoplankton biomass would have been obtained with a probe that measures also the fluorescence of phycocyanin, the photosynthetic pigment in cyanobacteria, because cyanobacteria has less chlorophyll a than other phytoplankton groups. As Vanajavesi is phosphorus limited or co-limited by phosphorus and nitrogen year around, reductions in phosphorus loading will likely improve the water quality. The main source of phosphorus to Vanajavesi is the nutrient loading from agricultural practises on the drainage basin. Efficient management of this diffuse loading will cause the phytoplankton biomass, especially the biomass of harmful cyanobacteria, to decrease. Nitrogen-fixing cyanobacteria is not dependent on the nitrogen concentrations in the water column, but the concentration of phosphorus. Significantly reducing the phosphorus loading is a prerequisite for the Vanajanreitti and Vanajavesi to be in a good ecological status by the year 2027.
  • Myyryläinen, Jerry (2020)
    Hypolimnetic withdrawal and purification is a new method developed to restore eutrophic lakes, which enables the removal and capture of nutrients such as phosphorus from hypolimnetic water. The method is currently being studied in a pilot-scale project at Lake Kymijärvi, Lahti, Finland. The project employs a closed-circuit system, in which the hypolimnetic water is pumped into a filtering system onshore, where the dissolved phosphorus is first precipitated. There are two possible methods for precipitation: aeration of water, in which dissolved phosphorus is precipitated by iron hydroxides as the water aerates, and addition of calcium hydroxide (Ca(OH)2) (hereafter “chemical treatment”), in which dissolved phosphorus is precipitated as hydroxyapatite. The water then flows through a nutrient filter, which traps the precipitate. The nutrient filter consists of two parallel filters, which enables the simultaneous comparison of two different filter materials. Finally, the water is returned to the lake via a wetland. A closed hypolimnetic withdrawal and purification system like this has not been previously studied as a restoration method. The aim of this master's thesis is to study the operation of the hypolimnetic withdrawal and purification system of Lake Kymijärvi by comparing the phosphorus retention capacity with 1) two different filter materials and 2) two different precipitation methods. The compared filter materials were fine gravel (manufactured by Rudus) and calcitic waste rock (manufactured by Nordkalk). Additionally, the thesis investigates the ratio of phosphorus fractions (Ca-P and Fe-P) of the phosphorus trapped in the filters, the distribution of trapped phosphorus between different filter layers and the effect of the filter materials on the concentrations of calcium, iron, manganese and sulfur of the water flowing through the filters. The operation of the hypolimnetic withdrawal and purification system was tested during four hypolimnetic water test pumping periods in summer 2019. The material for this thesis consisted of water and filter material samples collected from the system during the test pumping periods. The water samples were used to determine the capacity of the filter materials to capture phosphorus and other elements. The filter material samples were used to study the ratio of different phosphorus fractions and the distribution of trapped phosphorus between different filter layers. Both filter materials captured phosphorus efficiently via both precipitation methods. At their highest efficiency, both materials captured over 90 % of dissolved phosphorus and over 75 % of total phosphorus. No statistically significant difference was found in the phosphorus retention capacity between the filter materials, nor the precipitation methods. Of other elements, both filter materials captured iron very efficiently during both precipitation methods, and manganese during the chemical treatment. The phosphorus trapped in the filters was not evenly distributed between different filter layers and most of the phosphorus was trapped in the bottom-most layer in both filters. The phosphorus fractions between the two precipitation methods differed less than expected. After water aeration, all the phosphorus trapped in the filters was bound to iron. Even after the chemical treatment, less than half of the trapped phosphorus was bound to calcium, with the remainder bound to iron. According to the results, it is possible to remove phosphorus efficiently from hypolimnetic water with the system, using whichever of the studied precipitation methods or the filter materials.
  • Mäkinen, Theresa (2022)
    The topic of forest fires has gathered a lot of media attention in recent years as it relates closely to climate change and other sustainability issues. The media has an important role in communicating these issues as it affects, how the public percieves them, how different sustainability problems are defined and what kind of solutions are seen plausible. I became interested in how the media represents the issue of forest fires. My aim in this thesis is to find out, how the Colombian news media has framed the Amazon rainforest fires. As my material I used the news articles from the Colombian news media El Tiempo. I definined my timeframe from July 2019 to september 2019 because at that time the news subject was of high interest. After the initial search I went through the articles and left out any irrelevant ones. I was left with 24 news articles. As an analytic tool I utilized qualitative frame analysis guided by Robert Entman´s definition of frames and used ATLAS.ti to make an initial thematic coding. After that I mapped out all the actors that were cited in the news articles and divided them into groups. Using these actor groups, I searched for the frames. There were eight actor groups, politicians and political organizations being the most prominent one. Looking at how these actors talked about the forest fires, two main frames came out: populist and scientific. The populist frame concentrated mainly on Jair Bolsonaro. In this frame there was a lot of nationalist and economic arguments and responsability was directed away from him. There seemed to be a lot of enemies also. The second frame concentrated in deforestation, climate change and the forest fires being a global issue. In this frame international actors used economic and political pressure in order to affect Bolsonaro´s policy solutions. The research showed, how difficult it can be to solve shared global problem and made visible a historical political division between authoritarianism and democracy. An other important notion is the lack of marginalized groups in the news media.
  • Dunkel, Eveliina (2023)
    Urban areas have a central role in human’s impacts on the planet. A persistent, fundamental and systemic transformation of urban areas to be more sustainable is a widely recognized pursuit. Involving a variety of stakeholders in decision-making and discussing how, why, and to whose benefit urban areas should be changed is central for governing urban transformations. The study elaborates which features and negotiations key stakeholders relate to sustainable urban transformation. This is done through a frame analysis, and a serious game is used in data collection to facilitate discussion between participants. The results of this study show how urban sustainability and transformation can be framed in many ways that highlight different aspects. Role of private businesses, a competitive setting between cities, trust between different groups and accountability to citizens are elaborated in the negotiations on sustainable urban areas. Urban transformation is discussed especially related to low-carbon traffic, greening urban areas, preventing climate-change related flooding, adding possibilities to participate decision-making and more adaptive city planning. The study concludes that open communication between stakeholders of urban transformation is crucial to build trust and understanding between groups, but demand for openness may contradict with the interest for urban areas to appear in good light to and desirable for businesses and new residents.
  • Österblad, Ika (2016)
    Parasitoid host interactions are intimately associated with food web dynamics as well as with evolutionary change. The parasitoid s possibility to expand its host range or switch to different hosts is affected by parasitic strategy. Strong specialization to a narrow host repertoire can arise e.g. if the larva spends considerable time in close contact with an active, developing host (koinobiosis). In contrast, an ectoparasitic larva, growing rapidly on a sessile host, does not have to be equally tightly adapted to host physiology. This may permit a wider host range. However, there are other restricting factors, such as egg production capacity. Extant parasitoids show a staggering species diversity, most notably among the Hymenoptera. Theories concerning speciation in association with host range have been developed, but draw from knowledge of merely a small part of this diversity. This study adds information by showing a number of radical host shifts in the evolutionary history of the ichneumonid wasp genus Gelis. Species of this genus exploit either insect prepupae or spider eggs. These are similar in being rather defenceless, aside from a protective silk covering. Nonetheless, differences are large enough to restrict Gelis species to each utilise only one of the two groups. In order to trace ancient host group shifts, host data was mapped onto a phylogeny constructed through bayesian analysis of sequence data. Sequences from the COI (mitochondrial) and ITS2 (nuclear, noncoding) regions were used. The results suggested at least four host group shifts within the genus. In addition, wing reduction was found to have occurred in two different lineages. Through COI barcode sequence clustering supported by morphological traits, a previously undescribed species from the G. bicolor-species complex was detected. The phylogenetic analyses also indicated the existence of further cryptic species, and the genus Thaumatogelis Schwarz was found to be nested within Gelis.
  • Pasanen, Amanda (2022)
    Urban energy transitions play a key role in achieving climate targets and keeping the climate crisis from escalating. The district heating system of Helsinki has been characterised as a path-dependent and locked in system that will face difficulties in transitioning away from fossil fuels. In 2021 the city owned energy company Helen announced that it will quit coal burning in 2024, which is five years ahead of the national coal ban prohibiting coal use for energy in 2029. The coal phase out of Helsinki is a concrete example of a demanding coal phase out in a northern city with high energy demand. This thesis aims at answering the research question on how the multilevel policy mix, consisting of policy instruments on the municipal level, the national level, and the international level, contributed to the coal phase out of Helsinki. Through a case study approach relying on ten expert and stakeholder interviews as well as complementary material consisting of key strategy documents, this thesis aims to widen the understanding of the role of policy and politics in sustainability transitions and urban energy transitions. This study covers both policymaking and implementation processes as well as system impacts of the policy mix contributing to the coal phase out of Helsinki. Through empirical reviews the thesis contributes to the conceptualisation of policy mixes on multiple governance levels by studying the combined impact of policy instruments formed at the local, national, and international level. Regulatory policies on the national and international level (emissions trading, national ban on coal, taxation etc.), policies supporting low-carbon solutions on the national level (tax-exemptions) and climate target setting as well as support for low-carbon solutions on the municipal level (deregulation, innovation competitions) altogether contributed to the coal phase out. The findings of this study are in line with previous research emphasising the destabilisation of fossil fuel regimes to achieve transitions towards sustainability. Incorporating the elements of policy processes and strategies as well as policy effects and feedbacks into the concept of policy mixes is important to assess the efficacy and long-term impacts of policy mixes. The coherence of policies on multiple governance levels and the balance between regime destabilising and niche creating policies is also important in ensuring transitions towards sustainability. The results of this study support previous research findings on cities being important arenas and actors for sustainability transitions. Policies from different governance levels intersect on the urban level and decisions on infrastructure transformation are made on the municipal level.
  • Jeltsch, Markku Michael (1997)
  • Zhou, Quan (2020)
    Leaf senescence is a developmental and physiological phase in plants to end leaf development. Environment factors such as drought stress, extreme temperature, and pathogen threat and internal factors including age and reactive oxygen species induce leaf senescence. Some phytohormones such as jasmonic acid and salicylic acid play a key function in cell death in plants. WRKY transcription factors is known as one of the largest transcription factor family in plants which regulates a variety of plants processes. WRKY75 which belong to WRKY transcription factors has shown multiple functions in plant development like regulation of Pi starvation responses and root development and flowering. In my thesis, I focused on the role of WRKY75 in senescence and stress responses. WRKY75 was identified as a positive regulator of cell death in Arabidopsis. WRKY75 can promote salicylic acid biosynthesis by promote transcript levels of SID2 and also cause hydrogen peroxide accumulation by suppressing the transcription of CAT2. Hydrogen peroxide and salicylic acid can promote WRKY75 transcription at the same time. To evaluate the function of WRKY75 transcription factor in SA signalling and cell death, three lesion mimic mutants acd5, cat2, dnd1 and their corresponding wrky75 double mutant were used. Interestingly, no different phenotypes were found between acd5, cat2, dnd1 and their corresponding wrky75 double mutants in cell death and hydrogen peroxide accumulation detection in Arabidopsis leaves. Meanwhile, marker genes transcription levels were not different in both short day and long day growth condition. However, different phenotypes were observed in botrytis infection. Based on these results, we formed a hypothesis that gene redundancy could influence genetic characterization of WRKY75. To overcome this problem, SRDX-WRKY75 chimeric repressor transgenic lines were generated. The SRDX domain act as a dominant negative regulator to suppress WRKY75 target genes. In future research, these new lines can be used to test transcript levels for putative WRKY75 target genes.
  • Taskinen, Juuso (2019)
    Human umbilical vein endothelial cells are responsible for maintaining and forming new vessels from existing ones, in a biological process called sprouting angiogenesis. Sprouting angiogenesis is a crucial mechanism for the resolution of hypoxia and normal development of tissues. It also plays a key role in internal plague hemorrhages, which can lead to embolisms and other cardiovascular complications. Angiogenesis is also crucial for cancer development. Sprouting angiogenesis is initiated by hypoxic tissue excreted vascular endothelial growth factor gradient, which induces normal endothelial cells into either a proliferative stalk cell or a signal sensing tip cell phenotype. Both of these cell types depend on the rapid flow of lipids to their plasma membrane, either to form plasma membrane protrusions in tip cells or as new plasma membrane material in dividing stalk cells. This flow is envisioned to involve both vesicle-mediated and non-vesicular mechanisms. A major non-vesicular route of lipid transfer occurs at membrane contact sites via lipid transport proteins. Furthermore, lipids can be transported to the plasma membrane by the direct fusion of vesicles or endosomes with the plasma membrane This thesis set out to explore the role of two membrane contact site proteins, oxysterol-binding protein- related protein 2 and protrudin, in angiogenesis and lipid transfer. Their role was examined by RNA-sequencing transient knock-down samples of these proteins in HUVECs. The RNA-sequencing data was examined by differential expression, gene ontology overrepresentation and gene set enrichment analyses. Gene expression analysis provided almost 10 000 significantly changed transcripts (adjusted p-values < 0.05), in each silenced cell type. The distribution of differentially expressed genes in oxysterol-binding protein- related protein 2 silenced cells, is skewed toward negative fold changes, whereas the distribution of differentially expressed genes in protrudin silenced samples is normally distributed. The results also show significant changes in gene ontologies related to proliferation, cell cycle, angiogenesis as well as hypoxia in both sample types. Gene set enrichment analysis showed upregulation in angiogenesis related pathways, such as the PI3K-Akt and MAPK pathways, in both samples. Significant downregulation was present in cell cycle related pathways and cholesterol biosynthesis pathway in both ORP2 and protrudin silenced samples.
  • Kuivala, Tea (2023)
    Lynch syndrome (LS) is the most common cancer predisposition disease caused by dominantly inherited pathogenic variant (PV) of a mismatch repair (MMR) gene leading to a defective gene allele. The four major MMR genes encode MMR proteins – MSH2, MSH6, MLH1 ja PMS2 – that participate in the proofreading and repairing of the daughter strand for mismatches after every replication. The inherited PVs predispose to cancer development as only one somatic allele loss is required for biallelic loss according to the Knudson’s “two-hit” hypothesis. The biallelic loss of an MMR-gene leads to disrupted protein function altering the MMR process. When mismatches are left unrepaired, genomic instability is caused, which can eventually lead to tumorigenesis. Especially, the risk of colorectal cancer (CRC) and endometrial cancer (EC) is increased in LS. The predisposition syndrome, LS, is important to detect as early as possible to decrease the risk of cancer by prevention and surveillance. The MMR genes and their defects vary in their consequences to the repair process considerably, and thus, it is crucial to know the different characteristics and functional effects of them when estimating the level of cancer risk. Variants of uncertain significance (VUS) are especially prevalent among LS variants. More information about their impact to the disease can be acquired by in vitro and in silico methods, for instance. The main goal of the efforts for early detection and prevention is to reduce cancer morbidity and mortality. In this thesis, the pathogenicities of MSH2 and MSH6 variants were studied with DiagMMR assay, which has been developed for studying the protein function of these genes. In addition to the traditional agarose gel electrophoresis (AGE), the samples were also analyzed by a fragment analyzer, Labchip, that bases its function on capillary electrophoresis. This way the MMR detection efficiency of the methods could be compared. Samples were collected as skin biopsies from controls and LS patients with known MMR gene variants by Helsinki University Central Hospital (HUCH). InSiGHT database, that collects the different MMR-gene variants and their pathogenicity classification, was used to ensure that different kinds of variations, both pathogenic (class 5) and currently internationally unlisted variants, were analysed. The skin samples were cultured to acquire primary fibroblasts for nuclear protein extraction. The level of pathogenicity was revealed by MMR-protein activity when substrate DNA with a mismatch was added to the extract. Then, restriction enzymes were used for producing fragments of different lengths, depending on the repair action, and the MMR efficiency was visualized by both electrophoretic methods. Additionally, MAPP-MMR tool was used for studying the MSH2 mismatch variants in silico. By comparing the results from these two methods, we show that the more quantitative Labchip brings diagnostic value to DiagMMR suggesting 100% specificity (n=10) and 90,9% (n=11) sensitivity in reference to the variant information. For example, MSH6 c.3103C>T, which is listed as pathogenic in InSiGHT, was more consistent in giving a MMR deficient (dMMR) result with Labchip. Difference in the functional detection could be seen particularly with the MSH6 variants, but the differences were less notable when Labchip results were compared to the previous interpretations of the samples made based on the validated DiagMMR protocol. With the unlisted MSH6 variants, c.3139dupT was detected as dMMR by Labchip which was in unison with the previous interpretation. Another one, MSH6 c.551delA, was seen as MMR proficient (pMMR) in all the results by both the methods, and with the previous interpretation being unclear, which highlights the importance of further testing of this variant. There was also one unlisted variant (c.1805T>C) among MSH2 for which we got uniform dMMR results in two patients. The high MAPP-MMR score (25.150) for the MSH2 p.Leu602Pro amino acid change also supported the evidence gained of the pathogenic nature of this variant. As a conclusion, DiagMMR can be used reliably for MMR efficiency analysis, especially when performed together with a more quantitative analysis method.