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(2023)Tämä pro gradu -tutkielma tarkastelee vuosina 2021-2022 Suomessa esitettyjä ilmastoyksiköiden käyttöön liittyviä mainos- ja markkinointiväittämiä ja niiden laatua. Tällaisia väittämiä ovat esimerkiksi yleisesti käytetyt hiilineutraalius- ja kompensaatioväittämät. Työ esittää katsauksen siihen, kuinka tarkkaa ja asianmukaista tietoa vuosina 2021-2022 mainos- ja markkinointiväittämät ovat esittäneet. Työssä väittämiä tarkastellaan tulevien EU-sääntelyn edellytysten sekä helmikuussa 2023 julkaistujen kansallisten suositusten valossa (Laine ym., 2023). Sääntelyn ja kansallisen toimintakentän muutoksien kautta työ tutkii väittämien mahdollista tulevaisuutta ja muutoksia väittämien tulevassa käytössä. Merkittävin yksittäinen ilmastoyksiköihin perustuvien väittämien tulevaisuuden käyttöön vaikuttava tekijä on väittämien tekemiseen käytettyjen ilmastoyksiköiden kaksoislaskennan välttäminen. Kapea-alaisen pilottitutkimuksen avulla työssä testataan kaksoislaskennan riskin arviointiin esitettyä menetelmää (Laininen ym., 2022) sekä arvioidaan väittämiin liittyvää riskiä. Työssä hyödynnetään kahta erillistä aineistoa, joiden avulla tutkitaan mainonnassa ja markkinoinnissa esitettyjen väittämien eroja. Väittämien laatua tutkitaan analysoimalla niiden syvyyttä eli sitä, kuinka tarkkaa tietoa väittämä tarjoaa sekä asianmukaisuutta eli sitä, onko väittämässä annettu tieto selkeää ja yksiselitteistä vai mahdollisesti harhaanjohtavaa. Työssä toteutetun analyysin perusteella suurin osa vuosina 2021-2022 mainonnassa ja markkinoinnissa esitetyistä ilmastoyksiköihin perustuvista väittämistä oli harhaanjohtavia. Mainonnassa ja markkinoinnissa esitettyjen väittämien välillä esiintyi kuitenkin merkittäviä eroja. Analyysin perusteella mainonnassa esitetyt väittämät olivat markkinointiväittämiä heikompilaatuisia sekä syvyydeltään että asianmukaisuudeltaan. Arvioinnin perusteella väittämiin liittyvät nykyiset markkinointikäytännöt eivät yleisesti vastaa niille esitettyjä kansallisia suosituksia eivätkä tulevia EU-sääntelyn edellytyksiä. Väittämien tarkkuuteen ja yksityiskohtaisuuteen liittyvien markkinointikäytäntöjen lisäksi tulee tulevaisuudessa ottaa huomioon väittämiin liittyvä kaksoislaskennan riski, joka pilottitutkimuksen perusteella koskee oletettavasti merkittävää osaa nykyisistä markkinoilla esitetyistä väittämistä.
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(2013)In this master's thesis, I examine 21st century criticism of economic growth. The aim of the study is to understand what economic growth represents to growth critics. The research question is: what are the central themes of contemporary growth critique? The research material consists of three books: Tim Jackson's Prosperity without growth – economics for a finite planet (2009), Peter Victor's Managing without growth – slower by design, not disaster (2008) and the Finnish translation of Serge Latouche's Petit traité de la décroissance sereine (2007, Finnish translation Jäähyväiset talouskasvulle published in 2010). A qualitative content analysis was conducted on the material. In this method, manifest and latent meanings of the text are condensed and categorized in order to identify the key themes of the text. The analysis reveals three central themes in the criticism of economic growth. Each offers a different perspective to economic growth, to the proposed alternatives and to the opposition between growth protagonists and antagonists. First theme is growth as a phenomenon, which focuses on concrete ecological and social impacts of economic growth. The main argument of the growth critics is that the social and ecological costs of growth exceed its benefits in the western countries. In addition, they argue that economic growth cannot be viably combined with reducing ecological impact of human activities. The second theme is growth as an institution, which focuses on the institutional dependence on growth as well as institutional structures supporting growth. The critics' opinion is that these institutions now form a vicious circle in which people serve the economic growth and not vice versa. Also the proposed institutional change for disentangling society from growth is relevant to this theme. The third theme is growth as an ideology, which focuses on economic growth as a hegemonic belief and value system as well as a political goal above other goals. Under this theme, the growth critics promote emancipation and outline an alternative ideology. One main conclusion of the study is that the growth critics are not in favour of the opposite of economic growth, i.e. they do not promote a diminishing economy as an end in itself. Instead, their critique opens up a discussion on an alternative society which does not revolve around the economy and its size. However, this alternative is not pictured very clearly in the research material. It seems that the growth antagonists are able to describe what they oppose more elaborately than what they support. Another conclusion is that there is an internal tension within current growth critique. When examining economic growth as a concrete phenomenon the critics suggest indifference towards economic growth. Yet, under the other two themes the approach is everything but nonchalant since dismantling the institutions and ideology of growth will hardly be achieved without intentional resistance. Since the three books analyzed lean on and draw from earlier and contemporary references critical to economic growth, the three themes might be utilized in analyzing and understanding growth critique in general. However, this should be verified in further studies. What is more, when applied to other texts one might discover new themes not covered in this study. Because this study concentrates on the aspects that the three books representing growth critique have in common, in the future one should examine whether there are different schools of thought within the 21st century growth critique. Another interesting subject for further studies would be to apply the three themes to analyzing degrowth visions and possible degrowth experiments.
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(2021)Tumors contain variable number of different immune cells that infiltrate the tumor microenvironment, such as tumor infiltrating lymphocytes (TILs). More research is needed to understand the functional and clinical importance of various TIL subgroups in cancer. Understanding the differences between individual cancer patients will help development of new treatment methods and discovering why only some patients respond to immunological treatments. Renal cell carcinoma (RCC) is the most common kidney cancer type with good overall survival prognosis when the tumor is surgically removed before it has metastasized. However, the prognosis of RCC is significantly decreased when the cancer has spread. The aim of this master’s thesis project was to characterize the tumor infiltrating lymphocyte populations in patient derived RCC samples. Characterization was done with flow cytometry and a custom antibody panel designed to detect various lymphocyte subpopulations. We also wanted to further study the TILs by expanding the lymphocytes from the tumor samples and test their function in an impendence-based assay against matched autologous tumor cells. Based on the flow cytometry results, the different RCC subtypes in the cohort showed some variation in TILs. Still, more research is needed to investigate these differences. We were able to culture the TILs from the RCC tumor samples, and most of them were CD4+ T cells expressing memory markers CD45RO and CCR7. Some expanded TILs expressed markers related to T cell activity and terminal differentiation. In conclusion, this thesis provided material and insights for future RCC TIL experiments as well as considerations for optimization needed in further studies.
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(2018)Life historyresearch seeks to explain how natural selection and ecological challenges shape organisms to optimize their fitness. A strong immune defense is energetically demanding to upkeep and there may be trade-offs among other life history traits. Investing a lot of energy to upkeep a strong immune defense in conditions where there are less pathogens and parasites might have negative fitness effects. Heliconius eratois a neotropical species of butterfly found widely in South America. The immune defense, ecologicalfactors affecting its immune defense, and possible life history trade-offs of the butterfly are currently not well known. Environmental moisture conditions have been shown to affect the diversity, quality and amount of microorganisms and parasites. The aim of this thesis was to use real-time quantitative PCR (RT-qPCR) to quantify immune gene expression of individuals of the butterfly species Heliconius eratocollected from different environmental moisture conditions. Additionally, individual variation in encapsulation rates, a physiological measure of immunity, was compared across the moisture gradient. Results indicate reduced expression of the gene encoding the antimicrobial peptide attacin in dry conditions, but no difference in encapsulation rates across the moisture gradient. Additionally, differential expression of the prophenoloxidase encoding gene was found between male and female butterflies. These results indicate a possibility of differential immune threats in different environmental moisture conditions in H. erato, but requires further study.
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(2019)The vagus nerve is the longest nerve of the autonomic nervous system. It innervates, among other organs, the stomach, the lungs and the heart, and it reaches several areas of the brain, including the locus coeruleus and the amygdala. The invasive stimulation of this nerve (vagus nerve stimulation, or VNS) is a currently used method for the treatment of refractory epilepsy and pharmaco-resistant depression (Englot et al. 2011; O’Reardon et al., 2006), but the impact that this technique might have on the brain physiology and functions is still under investigation. Various studies (Frangos et al., 2015; Yakunina et al., 2016; Hansen, 2019) have shown that VNS increases noradrenaline production in the brain, a neurotransmitter that is involved in several cognitive processes, such as sleep and mood control. Furthermore, in a study on patients with epilepsy, by Sun et al. in 2017, VNS appeared to have a clear effect on working memory and emotion-attention interaction. Nevertheless, VNS presents all the risks and potential complications that characterize invasive procedures requiring surgery. Therefore, research is now focusing on safer, non-invasive alternatives, such as transcutaneous vagus nerve stimulation (tVNS). This technique allows to stimulate the nerve through its sensory fibres, located in the cymba and tragus of the ear. The scope of the present study was to see whether tVNS would have the same effects on cognitive and affective functions as VNS. The sample for this single blind placebo-controlled study was composed of 30 healthy subjects between 18 and 45 years old. Exclusion criteria included a history of psychiatric, neurological or cardiovascular diseases. All subjects were asked to complete a computer-based task, the Executive Reaction Times-Test. Throughout the test the subjects alternately received an active or a placebo stimulation, and their brain activity was recorded for the whole duration of the test using a 64-channel EEG cap. The Executive-Reaction Times-Test was chosen for this study because it allows to test multiple executive functions simultaneously. The subjects were presented with a series of stimuli on a screen and were asked to react as fast and accurately as possible to “Go” signals, and to refrain from responding when “NoGo” signals appeared. The test started with a triangle pointing either up- or downwards, followed by a brief pause and a traffic light image. The traffic light showed either a red or a green light and included an emotional distractor in the form of a spider or a flower. The red and green lights were alternately used as “Go” or “NoGo” signals, and the rule changed at each test block. In order to complete the task, subjects needed to keep the image of the triangle in their working memory, stay focused on the stimuli and be ready to react or be able to inhibit any responses, thus several main executive functions are being tested: inhibitory control, working memory, attention and emotion-attention interaction. Active stimulation was delivered through clip electrodes that were attached to the tragus of the left ear, whereas placebo stimulation was delivered through clip electrodes that were attached to the left ear lobe. The subjects were not aware of the difference between the two locations. Only the data of 18 subjects was used for the results analysis, because of technical difficulties with the EEG data (some recordings were too noisy, some presented flat channels). The behavioural data was divided into reaction times and errors, which were separately analysed. The EEG data was used to extract the amplitudes of the ERP peaks N2 and P3. The former is a negative peak visible at 200-350ms; the latter is a positive peak visible at 300-500ms. Previous studies have shown the peaks to be associated with response conflict and inhibition (Falkenstein et al., 1999; Donkers et al., 2004; Smith et al., 2013). The behavioural data analysis did not show any significant effect of stimulation on reaction times or error amounts. The ERP analysis, instead, returned interesting results. We observed a main effect of stimulation (p=0.04) in “NoGo” conditions. There was a significant reduction in the N2P3 amplitude and the N2 amplitude in “NoGo” conditions, with active stimulation compared to placebo. These results seem to suggest that with tVNS, fewer cognitive resources are allocated to resolve the inhibitory task, without worsening the subjects’ performance. The lack of significance in the behavioural results might have been due to a ceiling effect, with the Executive Reaction Times-test being too easy for our sample. Overall, the number of errors was too low to conduct a reliable statistical analysis. Nevertheless, the effects we observed on brain physiology would suggest that further research is needed to explore the actual impact of tVNS on cognitive and affective functions.
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(2022)Climate change is expected to cause salinity change in the Baltic Sea and therefore may affect organisms living in the Baltic such as plankton. The microbial loop is an important part of the plankton food web. It consists of heterotrophic bacteria, nanoflagellates and ciliates and is connected with the classic plankton food chain through interactions with primary producers and mesozooplankton. Therefore, salinity affects the functioning of the microbial food web not only directly, but also through salinity induced changes on primary producers and mesozooplankton. In this master’s thesis I studied the effects of salinity change on microbial loop components bacteria, nanoflagellates and ciliates in an outdoor mesocosm experiment containing four salinity treatments with salinities of 3.5, 5.5, 7.5 and 9.5, three replicas each. The experiment took place offshore at the Tvärminne Zoological Station. Bacteria were sampled from the mesocosms every other day and nanoflagellates and ciliates every 6th day. Bacteria were analysed with the flow cytometer, nanoflagellates with epifluorescent microscopy and ciliates using an inverted microscope. The effects of salinity on microbial loop components were statistically tested using linear mixed effects models. Results of the experiment show that salinity had an indirect effect on microbial loop components through changes in mesozooplankton composition. There were significant differences between high and low salinity treatments in bacteria abundance and composition, the interaction strength between HNFs and bacteria and in the mean cell size of ciliate communities. These were mainly caused by differences in mesozooplankton community structure between salinity treatments, which had cascading effects on the strength of top-down and bottom-up control on the trophic levels of the microbial loop, leading to changes in bacteria abundances and composition. Based on the results of this thesis, more studies are needed to detect the effects that changes in the composition and functioning of the microbial loop might have on the ecosystem. Further research should also focus on the significance of the structure and diversity of the communities within the microbial loop as well as the functional roles of different species in the microbial food web.
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(2022)The intensification of agriculture is one of the main drivers of biodiversity loss worldwide. One of the intensification shifts has occurred from cattle grazing on biodiversity-rich semi-natural grasslands to ceased grazing or grazing on cultivated species-poor grasslands. While the effect of different grazing pressure on biodiversity in semi-natural grasslands has been studied extensively, little is known of how current grazing regimes on cultivated grasslands affect biodiversity and ecosystem services in different farming systems. Here, we investigated how arthropod abundance and potential ecosystem services are related to varying grazing pressure on cultivated grasslands at conventional and organic farms with meat or dairy production. We sampled aerial arthropods with sticky tape traps in four land-use types within the farms. Relative arthropod abundance was derived from the tapes using an imagery analysis, and the numbers of pollinators and predators from 4 taxonomic groups were counted. The results showed no difference in the relative arthropod abundance in relation to grazing pressure, but there was weak evidence for higher predator abundance at low and high grazing pressure. The relative arthropod abundance showed a positive trend in organic farms. However, pollinator abundance was higher in conventional farms, and predator abundance did not differ between farming systems. Land-use type was related to the occurrence of predators and pollinators: both groups had the lowest abundance in farmyards compared to cultivated pastures, silage fields, and cereal crop fields. Predator numbers were also higher in silage fields than in the other land-use types. However, there was no significant interaction between land-use types and farming systems in their effect on the arthropod groups. The results suggest that grazing pressure on cultivated grasslands has a minor or negligible impact on arthropod abundance in the two commonest farming systems. However, the effect of farming systems on relative arthropod abundance might be obscured by low sample sizes, high abundance of only a few species, and other variables not included here, such as the use of manure or pesticides. In addition, pollinators included only two taxonomic groups, potentially leading to results not applicable to all pollinators. Consequently, more large-scale studies with higher sample sizes and the inclusion of arthropod diversity and data on the key on-farm practices and landscape structure are needed to disentangle the relationship between biodiversity and grazing on cultivated grasslands in Finland.
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(2024)Peatlands are a significant carbon and nitrogen reservoirs, making them potential sources of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions. Variations in water table level change the oxygen content of peat, affecting the oxidation-reduction or redox state of the peat, which is known to influence the biochemical processes and thus greenhouse gas (GHG) emissions. The aim of this study was to assess the effect of controlled anoxic redox conditions and inorganic electron acceptors (TEAs) on redox potential (Eh), and N2O, CH4, and CO2 emissions. In this study during an anaerobic incubation experiment, the rates of formation of these GHGs and Eh values as a function of time were measured from drained (D) and undrained (UD) peat of three nutrient levels: mesotrophic (ME), oligotrophic (OL), and ombrotrophic (OM). Redox conditions were controlled to three levels by nitrate (NO3-), ferric iron (Fe3+), and sulphate (SO42-). In addition, measurements were performed on untreated (Ctrl) peat. The peat was in an anoxic state throughout the incubation (Eh < 300 mV) and the values were in the order of TEA reduction, even though they were mainly in the iron and manganese reduction zones, probably due to the naturally high iron content of the peat. As expected, N2O formation was highest in flasks with added NO3-, and N2O formation was weak and ceased without addition. CH4 formation was reduced in flasks with added NO3- or SO42-, and SO42- addition also inhibited CO2 formation on which NO3- addition had no effect. In contrast, the addition of Fe3+ increased both CO2 and CH4 formation compared to Ctrl treatment, and it is possible that methanogens were involved in the reduction of Fe3+. In Ctrl flask, the redox state did not decrease to the lowest level compared to the other treatments as expected, but the Ctrl treated UD ME peat had the highest CH4 formation at the end of incubation. For all treatments, GHG emissions were higher from nutrient-rich peat in the descending order ME > OL > OM. In general, UD peat also had higher gas formation than D peat. All GHGs were formed the most while Eh values were around 0 mV and the value was especially high for CH4 formation, probably due to the linkage between methanogens and iron. The poor ability of the Pt electrode to detect NO3- or oxygen was the most likely reason for the variable and low Eh values of the flasks with NO3- addition. For the same reason, oxygen leakage of the anaerobic chamber was most likely responsible for the varying Eh values measured from Ctrl treated OM peat. This study suggests that Eh measurement is a useful predictor of the redox state and reactions, but it must be considered together with other measurements and analyses such as microbial analysis, nutrient analysis, and GHG measurements to predict redox processes and GHG emissions in anaerobic peatland. In particular, the role of iron on CH4 emissions requires further research.
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(2020)Ongoing climate warming has unprecedented impacts on glacial melt and associated fjord systems in Greenland. As the glaciers are shrinking, freshwater inflow to the sea is increasing resulting in increased nutrient supply by upwelling. In this study I examined environmental factors impacting marine primary productivity, biomass (chlorophyll a), phytoplankton abundance and species composition along a transect from the glacier front to the outer fjord in Godthåbsfjord, SW-Greenland, in August 2019. Gradients in nitrogen and phosphate concentrations were explained by glacial runoff and coastal water inflow while silicate concentration did not follow these patterns. The main variables explaining phytoplankton biomass distribution were nitrogen together with phosphate concentrations, salinity, and depth. Silicate limited waters were strongly dominated (≥ 90%) by the diatom Chaetoceros socialis, which had a strong influence on phytoplankton community response to environmental conditions. High dominance of C. socialis was also related to high species richness. Nitrogen depleted waters were usually related to relatively high abundances (9–46%) of mixotrophic Dinobryon balticum. Higher number of species and higher dominance of C. socialis was detected closer to the glacier. Phytoplankton abundance and biomass (chlorophyll a) were higher in the inner fjord region, whereas primary productivity had the opposite pattern (higher productivity in the outer fjord). This suggested that an autumn bloom was peaking in the inner fjord, whereas in the outer fjord the autumn bloom was still developing. Thus, glacial surface runoff and subglacial discharge contributed to higher phytoplankton abundance and chlorophyll a concentrations, whereas primary production was also dependent on other factors such as light availability and vertical mixing. Melting of Greenland Ice sheet is predicted to accelerate in the future. Thus, the upwelling effect might increase, leading to transitory increase in marine primary production. Increased surface runoff might increase silicate concentrations benefiting diatom species, although turbid runoff water will also decrease the primary productivity due to light limitation. Nevertheless, if marine-terminating glaciers retreat further and become land-terminating glaciers, lack of nutrient upwelling will lead to faster exhaustion of nitrogen in the upper water column and primary productivity will eventually decrease. Thus, global warming and retrieving of glaciers will change the productivity of the fjord and inevitably shape the rich and unique fjord ecosystems of the Arctic.
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(2020)High Nature Value (HNV) farming systems hold significant natural values but have decreased drastically during the process of agricultural modernization. Biodiversity in Europe is dependent on these extensively farmed areas because they maintain habitats for many endangered species; e.g. 30% of Europe's butterfly species have declining populations and most live in natural and semi-natural habitats. European common agricultural policy (CAP) favour conventional agriculture, leading HNV agriculture in a foul position. HNV areas are often abandoned or replaced with intensive farming practices. Participatory agricultural innovation processes offer solutions to the distress of HNV farmlands. In these processes different actors – such as farmers, entrepreneurs, advisors, NGO and municipality representatives – are brought together to find localized solutions to the challenges of the area. HNV-Link project was active during years 2016-2019 identifying, developing and improving innovations in ten European HNV farming areas. In this thesis I examine the success of innovations in seven Learning Areas (LA) in terms of socio-economic viability, environmental conservation and cultural region. The data in this thesis is both quantitative and qualitative. I use mixed methods- approach where the statistical analysis and qualitative content analysis support each other. I carried out a survey for the LA coordinators where they responded how was the impact of the innovations to social, economic and environmental wellbeing. I complement the survey with data gathered by the project in 2016-2017. I conduct a qualitative content analysis to innovation fiches using Atlas.ti programme and a statistical analysis with IMB SPSS statistics programme with non-parametric tests. I compare the relation of socio-economic and environmental impact of the innovations, explicit aim of HNV conservation, recognition of environmental topics in the fiches and cultural region. Innovations were successful both socio-economically and environmentally. There was a possible synergy between economic and environmental impacts, which indicates economic viability of the LA’s improving HNV conservation. Innovations with explicit HNV conservation objective had more positive environmental impact than the ones without. Innovations with high recognition of environmental themes in fiches had slightly more positive environmental impact, but the difference was so weak that they fail to express the environmental outcomes reported in the survey. Congruent patterns didn’t occur inside cultural regions which might be due to the similarities of the areas or small sample size. The results display the inherent unpredictability of innovation processes, and the importance of holistic understanding and long-term monitoring of them.
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(2021)The heath vegetation in the Jauristunturit study area is highly affected by the reindeer fence that was built in the mid-1950s between Finland and Norway, to prevent summer grazing in the Norwegian side. In the study area, the Finnish and Norwegian pastures are used during different seasons, causing differences in reindeer grazing history, and with time differences in vegetation. Additionally, local topography also impacts the vegetation composition and structure creating variation in local vegetation patterns. My research questions are: How vegetation patterns differ between summer- and winter- grazed areas, and which plant functional groups have the most significant difference? How local topography affects vegetation patterns, and does the effect of topography differ between summer and winter pastures? The data was collected from five 400 m long transects that crossed the fence and had vegetation plots with 10-m intervals. The %-cover and height of each vascular plant, bryophyte, and lichen species were estimated from 0.25 m2 plots. Later, species data was grouped into functional groups and general linear models were used to analyze differences in cover, height, species number, biomass, and leaf-area indices between countries. Topography indices were calculated in GIS for each plot and analyzed with random forest models to find out the most important topography indices explaining vegetation patterns. The vegetation data was collected by four teams, and therefore, the comparability in the collected data between teams was analyzed. Significant vegetation differences were found in the ground layer, with higher cover and biomass of bryophytes on the Finnish side (mean biomass 168.2 vs. 65.2 g m-2). Reindeer lichens were more abundant on the Norwegian side (mean biomass 197.0 vs. 2.9 g m-2) which is visible in aerial and satellite images and in the field. Among vascular plants, evergreen dwarf shrubs had higher biomass and leaf area index on the Finnish side and dwarf birch had higher cover and height on the Norwegian side. Topography indices had a higher level of variance explained on the Norwegian side, and higher at the ground layer compared to vascular plants. Elevation had the greatest impact on vegetation, and after that, topography protection index for 50 m and depth to water stream network for 2 and 10 ha. The differences between data collectors were not considered to have a major impact on the results. The results indicate that there are significant differences in vegetation between summer- and winter-grazed areas, mainly in the ground layer, and most differences are caused by differences in reindeer grazing history, but also local topography has an impact.
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(2021)In the process of decomposition soil carbon is transformed into CO2 by microbial respiration, which makes decomposition a key process for understanding carbon cycling an releases of CO2. Since the northern permafrost regions contain half of all belowground carbon and the tundra regions are expected to be markedly affected by climate warming, it is of particular interest to understand how warming will affect decomposition in the tundra. Decomposition is however influenced by many factors, from climatic factors such as temperature and precipitation to the belowground organisms inhabiting the soils and the aboveground system dictating the litter that falls to the ground and is decomposed. Further, grazing has been shown to oppose some of the effects of warming on tundra. In this thesis I analyzed data collected from two long-term field experiments, one in Kilpisjärvi (NW Finland) and the other close to Kangerlussuaq Fjord (SW Greenland), both using fencing for manipulation of grazing regime and open-top chambers for artificial warming. My aim was to not only investigate how warming and grazing affect decomposition, but also to understand whether the magnitude of changes in decomposition can be explained by changes in plant community traits and soil characteristics. I found that in contrast to my hypothesis, warming decreased decomposition in Kangerlussuaq, where the soil was drier and contained less carbon than in Kilpisjärvi. I found no effects of grazing on decomposition, plant community traits nor soil characteristics in neither of the study locations. Neither did I find any consistent associations between changes in decomposition and changes in plant community traits, indicating that the effect of litter quality on decomposition is minor in these areas likely rather limited by climate. I found an association for increased decomposition when plant community C:N ratio and C:P ratio increased as a response to warming, but only in Kilpisjärvi, and since increased plant community C:N and C:P ratios are linked to resistant litter this positive effect is unlikely driven by enhanced litter quality. However, I did find a positive relationship between increased root biomass and increased decomposition as a response to warming that was consistent across areas and grazing regimes, indicating that warming can boost decomposition in different tundra habitats by promoting root growth.
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(2020)Boreal mires are natural sources of methane and contribute considerably to the global methane budget. Therefore, in order to comprehend the overall impact that these ecosystems have on climate change, it is essential to understand the factors that influence processes involved in methane production and consumption. Factors affecting methane flux vary between different mires, but there is also great spatial and temporal variation in flux within mires. In previous studies, temperature and water table position have been shown to influence methane flux, but vegetation could aid in explaining the small-scale variation. Vegetation can indicate spatial variation in water table position, but also affect methane flux directly by the transportation of methane through plant tissues, and by providing substrate for microorganisms through primary production. Furthermore, redox potential is a poorly studied factor that can reflect if chemical conditions in peat are suitable for methane production or consumption, making it a useful tool in predicting methane flux. In this thesis, I seek to identify if small-scale spatial variation in the methane flux occurs within the studied mire area. In addition, I strive to identify important controllers of the observed spatiotemporal variation in methane flux, with a specific focus on the effect of vegetation properties and redox potential. Methane and carbon dioxide fluxes were measured with the closed chamber technique at a boreal fen in Sodankylä (67°22'06.6"N 26°39'16.0"E) during the growing season in 2019. Flux measurements were carried out at nine measurement plots belonging to three different vegetation types: flark, lawn and string. Coverage and height of plant functional groups were followed during the summer and continuous redox potential was measured for each plot. CH4 fluxes of different plots and vegetation types were compared to study the spatial variation in methane flux. Generalized additive models (GAM) were used to determine which variables are best to explain spatiotemporal variation in methane flux over the growing season. Mean methane flux during the summer was 0.94 ug CH4 m-2 s-1 which is in the same magnitude as observed in a previous study at the fen. Some small-scale spatial variation in the methane fluxes was observed at the study site, with strings having lower flux than flaks and lawns. However, overall the spatial variation was small, while temporal variation in methane flux over the growing season was considerable. The best model, that was a combination of vegetation, redox potential and environmental variables, and it explained 72 % of the observed variation in methane flux. Vascular plant variables were the most important variables in the model, whereas moss functional groups were of lesser importance. Redox potential in deeper peat layers was also important in the model, but redox potential closer to the surface was not found to be significant. Vegetation is an important controller of methane flux, and this information could potentially be used when predicting methane flux over larger areas by using remote sensing to map vegetation characteristics. Redox potential, on the other hand, is relatively easy to measure, and the result suggests that it could provide a useful tool for improving the predictions of methane flux.
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(2020)The Clustered Regularly-Interspaced Short Palindromic Repeats (CRISPR) and CRISPR associated protein (Cas9) (CRISPR-Cas9) system is a widely used gene editing technology due to its potential to alter the genome precisely in desired locations. Due to the potential of the CRISPR-Cas9 system, the objective of the thesis is to improve the precise editing of genes by modifying the CRISPR-Cas9 platform. Ultimately, the aim is to develop a platform that can edit any mutation and repair it to a normal, functional gene in patient cells. In general, CRISPR-Cas9 provides opportunities in treating monogenic diseases, for example by modifying long-term hematopoietic stem cells in immunodeficiencies. CRISPR-Cas9 can target disease-causing mutation sites and introduce double-strand breaks. Afterwards, the native DNA repair machinery of a cell repairs the cut site either by more efficient, error-prone non-homologous end joining (NHEJ) or precise homology-directed recombination (HDR). In most clinically oriented genome editing studies, the desired repair outcome is the latter because it allows precise repair of the mutation according to the exogenous repair template. Despite all its positive features, the optimization of CRISPR-based editing system is crucial before medical use; CRISPR-Cas9 induces a p53-mediated DNA damage response, which leads to a transient G1 cell cycle arrest and hampers HDR-based precision genome editing. Other problems include the repair pathway depending on the cell cycle phase, repair template proximity, and off-target activity. This thesis demonstrates that Cas9 fusions allow addressing the problems mentioned above. Cas9 fusions with DNA repair proteins ensure improved editing efficiency at the close proximity to the target site in HEK293T, BJ5-ta and RPE reporter cell lines. In addition, Cas9 coupled with the engineered cell cycle timer, AcrⅡA2-cdt1, favors the editing at the S/G2 cell cycle phases avoiding the p53-mediated response. AcrⅡA2-cdt1 is a reversible, phage-derived CRISPR inhibitor that selectively inhibit CRISPR-Cas9 at the G1 cell cycle phase and releasing it at the S phase. This thesis provides extensive look on the CRISPR-Cas9 editing and its challenges in immortalized cell lines and primary cells. In the thesis, the generation of reporter cell lines is prior to the validation of the novel Cas9-fusions. Furthermore, the optimization of primary T cell and CD34+ hematopoietic stem cell electroporation with different electroporation systems brings the study closer to clinical applications. The thesis provides insights about the effect of the target site and the cell type for genome editing outcomes. The editing efficiencies depend on the Cas9 fusion protein, cell type and its proliferation rate. The editing efficiency in primary T cells and CD34+ hematopoietic stem cells can significantly improve by optimizing transfection and culturing conditions, such as concentration of the CRISPR-Cas9 complex, cell culturing time and electroporation program. Cas9 fusions improve the safety and efficiency of the CRISPR-Cas9 system depending the cell type and the proliferation rate of the cell. Timing the induction of double-strand breaks also improves the editing efficiency. Overall, the methods used in the thesis give useful tools for eventual translational applications.
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(2022)With the growth and concentration of urban areas, methods for minimizing the impacts of fragmentation and habitat loss on biodiversity are needed. Spatial Conservation Prioritization (SCP) methods, which holistically assess the connectivity of urban areas, provide an effective tool for prioritizing conservation efforts, but producing these analyses require large amounts of high-quality data on e.g., the spatial distribution of biodiversity features in the area. An index-based approach is a simpler way to evaluate the ecological quality of single corridors, and could be a cheaper alternative to SCP methods, especially in cases where prior environmental data is limited or there is a frequent need for new analyses. In this study, I created an index-based method to evaluate the ecological quality and functionality of wildlife corridors. The three-step approach included a literature review on factors affecting the functionality of wildlife corridors as well as the building and testing of the index. The main objective in creating the index was to provide a tool that is easy to use and interpret, and that could be used in decision-making to minimize human impact on nature. The index is based on scientific literature and provides information on the ecological functionality of wildlife corridors in facilitating the dispersal of organisms. From the literature review I identified certain key elements of functionality for wildlife corridors. These elements included sufficient width of the corridor to form an undisturbed core habitat, the absence of barriers and disturbance within the corridor and the connectivity of the corridor habitat itself. When tested on fictitious example corridors, the index was able to differentiate wildlife corridors according to their ecological quality. To further test the index, it was applied on a real-world wildlife corridor located in Uusimaa as a case study. The index was found to be effective on evaluating the ecological functionality of wildlife corridors, but further development needs were also discovered. The most important next steps are to fine-tune the parameter values given to factors hindering dispersal (resistance values) based on an extended literature review, and systematic testing on real-world corridors to spot irregularities and possible mistakes. At its current state the index can be used to identify features that impede or promote the ecological functionality of the corridor, even without extensive prior inventories on the areas’ biodiversity features.
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(2024)Cameroon’s forests and forest lands are home to diverse indigenous peoples and local communities. Cameroon has endured many colonial administrations and missionary influences throughout its history with British, French, and German rule having all left their mark on the nation’s land, plantation, and forestry sectors while realising their interests. In particular, the representation of indigeneity remains tainted within and beyond today’s land use sector and forest policy arena, and its related businesses and financial services. This thesis analyses the British colonial business media landscape to examine the dominant discourses surrounding the indigenous within the context of Cameroon’s land, forests, and plantations. Through understanding the narratives that have historically been broadcast to society and the public via business media, a greater understanding of the current status quo within the forestry sector, and therefore the workings of ‘inequality machines’ and neocolonialism, can be investigated. Furthermore, business media such as newspapers and magazines historically played a central role in the colonial enterprise, informing and shaping entrepreneurial activities but also legitimising the colonial project and providing narratives to enable the realisation of interests and profits. This research examines local and indigenous narratives and considers how these representations link to the colonial enterprise. Qualitative research methods are adopted, using a systematic literature search to identify articles from four prominent British business media sources (The Economist, The Guardian, The Observer and The Times). Search criteria, in the form of two key word search strings, selected 303 relevant articles and constructed the archival landscape of Cameroon in British colonial business media from the 1850s through to the early 2010s. Newspaper articles were inductively coded using Atlas TI software with the aim to explore the main research questions: • How does British business media represent and legitimise the treatment of indigenous peoples in the context of Cameroon’s land, forests, and plantations? • How has this evolved over time? Results from coding demonstrate the emergence of 4 main code groups that aid the legitimisation and justification of indigenous exploitation in the context of indigenous representation: Comparing, Centring, Controlling and Fearing. Power dynamics, temporality, and the linkages between these core themes, also play a predominant role. What emerges as most influential is the way in which British business media shifts its representation and legitimisation of the treatment of indigenous peoples through time, whilst continuing to reinforce power inequalities. Ultimately, indigenous representation and narratives within the British business media ‘seem’ to improve, but this is largely from the colonisers’ perspective, or to be received by the colonial gaze.
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(2022)Puberty initiation is a crucial physiological process in human development. A group of hypothalamic neurons secreting the gonadotropin-releasing hormone (GnRH) and expressing the kisspeptin receptor (KISS1R) plays a key role in launching puberty. Furthermore, cellular KISS1R signaling has been shown to regulate GnRH expression and secretion. Although the in vitro differentiation of human pluripotent stem cells into GnRH-secreting neurons has been successful, it is of high interest to generate KISS1R expressing GnRH neurons. By utilizing the CRISPR activation technology, this study aimed to establish a conditional KISS1R-activation cell line using H9 human embryonic stem cells. Through controlling dCas9VP192 abundance using the Tet-On system combined with the dihydrofolate reductase destabilizing domain, the transcriptional activation of KISS1R was temporally regulated by the addition of two antibiotic drugs - doxycycline and trimethoprim. KISS1R expression was primarily assessed by qPCR and verified by immunocytochemistry and the use of a KISS1R-GFP reporter cell line. The main finding of this study is the achievement of a 6217 ± 2286 fold change in KISS1R transcription by introducing two guide RNAs (N = 3). Nevertheless, leaky gene activation was observed without drug treatment (fold change of 63 ± 51). Concludingly, this study successfully led to the generation of a KISS1R-activation cell line. After further characterization and refinement of the activation protocol, the established cell line will enable to investigate whether KISS1R upregulation modulates in vitro GnRH neuron differentiation, electrophysiology, hormone expression, and secretion in the future. Respective outcomes may lead to advances in understanding and treating pubertal disorders.
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(2022)Spontaneous and voluntary movements of infants effectively reflect the developmental integrity of brain networks. When it comes to the research of motor development, the use of intelligent technology has shown to provide objective, automated, and scalable methods for movement assessment. In addition to intelligent technology, research on the usage of surveys – in this case parental surveys – has looked at the untapped potential that parental viewpoint. Guardians have a unique and holistic image of the child’s development, thus data from parental surveys could be used to further help us to assess infant’s development. For this study, I studied how the parents’ time estimate on the positions their child spends time in holds up against the machine-learning based data obtained with the smart jumpsuit. Using the data acquired from the smart jumpsuit during the recordings, we can see the amount of time the child spends in each position. Aim was to study the relationship between these variables and gain further understanding on the utilization of parental perspective in the assessment of motor development. Data was collected from 19 video recordings and videos were annotated with Anvil video annotation software for child’s posture and movements, and the annotations were used for training a machine learning-based classifier of the smart jumpsuit. Only data regarding postures was extracted for further analysis. Parental surveys were carried alongside of recordings. In the survey of parental estimate, we asked the parent to assess how much time the child spends in a specific posture. Positions which the survey focused on were prone, supine, side, sitting, crawling, and standing. Data from the recordings as well as data from parental surveys were visualized with radar plots. In addition, correlation was visualized in a linear regression. Positions which had both correlation of higher than 0.5 and a significant p-value were sitting (p < .001**), crawl posture (p < .05*), standing (p < .001**), and supine (p < .05*). Results suggested that parents were successfully assess the time spent in following postures: sitting, crawling, standing, and supine. This indicates that parents have a holistic understanding of their child’s motor development, and the knowledge could be useful in the overall assessment of development, especially when it comes to children with developmental delay. The parent’s ability to accurately assess a child’s motor development helps the parent support the child’s development.
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(2023)Faculty: Faculty of Biological and Environmental Sciences Degree programme: Master’s Programme in Neuroscience Study track: Cell and Systems Physiology Author: Mélina GUILLON Title: Inflammatory activation of Macrophages by Triglyceride-Rich Lipoproteins in Atherosclerosis Level: Master’s thesis Month and year: August 2023 Number of pages: 38 Keywords: Atherosclerosis, Inflammation, Triglycerides-Rich Lipoproteins, Emulsion Particles Supervisor or supervisors: Dr. Katariina Öörni Where deposited: Helsinki University Library Additional information: Background: Inflammation is a key factor in atherosclerotic cardiovascular disease (ASCVD) and is present at all phases. It has been shown that reducing inflammation by blocking cytokine pathways diminishes the risk of stroke and myocardial infarction. Despite the well-established linked between lipoproteins and atherosclerosis, little is known on the specific effect of lipids on inflammation. In this study, we investigated the impact of triglycerides-rich lipoproteins’ (TRLs) lipids on inflammation in the context of atherosclerosis. Methods: TRLs were isolated and purified from pooled plasma of healthy volunteers, and emulsion particles (EPs) generated by sonication using lipids extracted from TRLs. TRLs and EPs were characterized in size, triglycerides, and cholesterol content. THP-1 cells were treated with EPs, TRLs, and modified EPs (oxidation, vortexed, and lipolysis with PLA2), and the release of pro-inflammatory cytokines (IL-1β and TNF-α) was detected with ELISA. Results: EPs were successfully synthesized by sonication using an ultrasonic probe. EPs induced cytokine secretion from THP-1 cells (N=4). Modified EPs (Oxidized EPs, vortexed EPs, and PLA2-treated EPs) did not increase cytokine secretion (N=4). Conclusion: Our findings suggest that TRLs’ lipids contribute to inflammation and that TRLs may play a crucial role in the pathogenesis and pathophysiology of ASCVD. Inflammatory properties of TRLs should be extensively investigated in the future for the development of preventive and curative strategies.
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(2022)The composition and dynamics of the early life gut microbiota plays a major role in establishing neonatal immunity and is suggested to have multiple impacts on the child’s long-term health. Meanwhile, the composition of the infant gut microbiome has been shown to be affected by the birth mode, infant health and diet. However, the characterization of the infant gut microbiome and its impact on the host’s health is still challenging as the contribution and importance of multiple co-factors on the early microbiome during infant growth is still poorly understood and characterized. The Health and Early-life microbiota (HELMi) is a cohort of more than 1000 healthy Finnish infants currently followed from birth to 4-5 years old. By now, the HELMi dataset comprises more than 400 whole genome shotgun metagenomes obtained from stool samples from 80 infants and parents, but also an in-depth characterization of the families’ lifestyle, environment, health and nutrition, allowing for a precise and cutting-edge characterization of the early gut microbiota. Based on the datasets from the HELMi, this project used Metaphlan3, Kraken and Braken to determine the best computational approach for the taxonomic profiling of the metagenomic reads. Then a PERMANOVA test was performed to evaluate and determine the factors significantly associated with the compositional microbiota variation within the infant gut metagenomes. This study first identified technical factors introducing bias in taxonomic profiling (e.g., DNA extraction batch), which served as confounders in the analysis of environmental and host variables. The investigation of these biological factors indicates that pre-natal and peri-natal variables such as the mode of delivery significantly impact the infant gut microbiota, while we did not identify any significant impact of breastfeeding habits and medication exposures in this study.
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