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Diesel, which belong to the fossil fuels, have been exposed recently because of global warming and because of decrease of known fossil fuel reserves. It has been estimated that reserves of fossil fuels will last next 40-50 years. Burning of fossil diesels will cause not only carbon dioxide emissions but also particle and metal emissions. There have been attempt to develop alternative energy sources. Growing alternative, which have came to the market, is renewable diesels, which can be produced from many sources such as reeds and biowaste. Biodiesels differ from fossil diesels by their chemical structure. Contrary to fossil diesel, completely renewable diesels do not contain aromatic compounds and they burn more purely. Diesel might end up in soil in accidents. Behaviour of fossil diesels in a ground is well known, however, the behaviour of renewable diesels is not known so well. Even though solubility of renewable diesels is similar with fossil diesels, renewable diesels may have different behavior due to different chemical structure compared with fossil diesels. Soil removal and taking the soil to be cleaned up is the most popular way to clean diesel contaminated soil resulted from diesel leaking. Alternative way to clean diesel contaminated soil is to use bioremediation where the microbes are used. In bioremediation microbes are added to the soil or activity of the microbes is boosted by improving living conditions of microbes by adding nutrients and oxygen. In this master thesis spreading of three different diesels qualities in soil and with water in laboratory were viewed. Results of the laboratory experiment were compared to the result of Katariina Lahti-Leikas’ lysimeter experiment in Jokimaa. Diesel qualities used in experiment were completely fossil EN590, partly renewable ProDiesel and completely renewable NEXBTL. Experiment were executed in soil columns in laboratory conditions where pure lysimeter sand were exposed to diesel. Biostimulation were made to half of the soil columns using urea that every diesel had natural decomposition and biostimulation. Soil columns were watered and hydrocarbons C10-C40 from collected water below the column were analysed. In addition, soil samples were collected and hydrocarbons C10-C40 were analysed. The pH of the soil and water samples were followed throught the experiment. Biostimulation decreased concentration of hydrocarbons in the water in every diesel quality. Biggest concentration were in water from NEXBTL columns which move in soil mostly in NAPL. In soil samples there was not the same kind of decrease in hydrocarbon concentration as in water samples. Diesel moved from the upper part of the soil columns to the lower part of soil columns during the experiment. The reason why biostimulation did not decreased the hydrocarbon concentration in soil is probably because the experiment period was too short. Other things to affect the result are probably wrong comparison of nutrients or lack of oxygen, which have slowed down decomposition of hydrocarbons. The results of this study are consistent with the results of Katariina Lahti-Leikas’ lysimeter experiment in Jokimaa.

Finnish matriculation examination in biology transitioned into a digital examination from traditional pen-and-paper examination in spring of 2018 as a part of larger process aiming to digitalize the entire matriculation examination. Tthe requirements for the exam have also changed: in addition to subject knowledge, the digital examination also requires the candidate to also be master the digital skills outlined in the Finnish high school curriculum, for example the use of image- and data processing programs. It has been suggested hat candidates from higher socioeconomic background benefit more from digital skill teaching. It has also been shown that some teachers overestimate the digital skills of the students, omitting parts of the teaching process that are integral for learning. Tthis study examines whether the matriculation examination answers requiring digital skills differ from questions that can be answered without advanced digital skills. Statistically significantly worse performance in questions requiring digital skills might indicate digital skill teaching that is insufficient compared to the skill level required in matriculation examination. Insufficient teaching may disproportionately affect those from lower socioeconomic background. The data of this study consists of 30 full-length answers from matriculation examinations of spring 2018, autumn 2018 and spring 2019, for a total of 90 full-length answers. The data was a randomized sample provided by Ylioppilastutkintolautakunta (Finnish Matriculation Examination Board). The differences were analysed with Mann-Whitney U-test and Fisher’s z-transformation. The study found that questions requiring digital skills were statistically significantly more popular than questions that didn’t require digital skills. Although the level of cognitive processing outlined by Bloom’s Taxonomy was lower in questions requiring digital skills, there was no statistically significant difference in the success (measured by attained score) between the answers. According to results, the digital proficiency of the candidates was at a sufficient level to answer to the questions.. The study also speculates on factors that could explain the observed differences in answer popularity, cognitive depth and difficulty level of the questions.

Schizophrenia is a debilitating psychiatric disorder associated with reduced life expectancy. The biological mechanism of schizophrenia is nebulous; however, many findings point to the central nervous system and neurons, where a reduction in dendritic spines has been indicated by previous research. The genetic findings support the involvement of synapses in the pathogenesis of schizophrenia. To study the biological properties stemming from genetics, relevant model systems and efficient methods are needed. Induced pluripotent stem cell (iPSC) technology offers a robust method for modeling the biological processes underlying schizophrenia. Somatic cells, e.g. fibroblasts, can be reprogrammed back to a pluripotent state resembling embryonic stem cells, and further differentiated into any cell type of the body, which might not be otherwise accessible. This allows establishing and characterizing neuronal cultures from patient and control cell lines, potentially revealing biological differences associated to the disease phenotype. The field of schizophrenia research has adopted iPSC technology and multiple studies have been conducted. These include assessments of synaptic density in the produced neuronal cultures, many of which reported decreased density associated with schizophrenia. In this thesis, a modified version of Nehme et al. (2018) protocol was used to differentiate iPSCs into neurons in co-cultures with human iPSC-derived astrocytes. The overarching aim was to construct an immunocytochemistry (ICC) -based assay to measure synaptic density in the produced co-cultures. First, suitable markers for characterization by ICC were tested and selected. The markers were selected to inform about neuronal identity, maturity, and synapses of the differentiated neurons. Next, the culturing conditions were optimized regarding the cell density and coating of the culturing wells. Finally, to estimate the utility of the assay, a pilot study was performed with three cell lines derived from a healthy control and a monozygotic twin pair discordant for schizophrenia. iPSCs from these cell lines were differentiated into neurons in co-cultures with astrocytes, and then characterized with ICC using selected markers and image analysis software. The synaptic density was quantified for each cell line. The performance of the assay was evaluated with analysis of variance (ANOVA) and restricted maximum likelihood model (RELM). An assay to quantify synaptic structures in mature neurons was established. The average synaptic density for all cell lines was approximately 1 synapse per 100μm of neurite. Analysis of the data produced with the assay revealed a notable batch effect and technical variation. This suggests that further optimization is needed to reduce variance from undesired sources. The pilot data suggests that the differences in synaptic density between cases and controls may be modest, further highlighting the need for minimizing noise in the assay to improve signal to noise ratio. However, indicated by power analysis, large sample sizes are needed to identify meaningful differences between cases and controls. In light of these results, more attention should be drawn to the methodology in the field of iPSC-based studies, as the principals of the assay constructed here were similar to other synaptic assays used in previous publications.

As a genome editing tool, CRISPR-Cas9 has provided a robust way to generate mutations in the gene of interest, at a certain time point, and in selected cell populations. The impairment of dopaminergic neurons in the substantia nigra is addressed to be one of the main pathologies of Parkinson’s disease. The histopathology of Lewy Bodies, with an undetermined role, accompanies the demise of DA neurons. Development of strategies for the prevention the neurodegeneration has a potential to slow down the progression of Parkinson’s disease. In this study, a novel, neuron-specific CRISPR-Cas9 system was developed for the purpose of dissecting neuroprotective pathways in primary dopaminergic neurons. The optimization of the tool was done by targeting EGFP at TH-positive neurons obtained from transgenic animals expressing EGFP in dopaminergic neurons. Complete loss of EGFP was achieved at day 6 after the introduction of the CRISPR-Cas9 via lentiviral vectors. There were no survival or transduction efficiency differences. Two significant pathways for the survival of dopaminergic neurons, the microRNA biogenesis and GDNF/RET signaling were selected to collect the preliminary data. Dicer, Trbp, Translin, Ago-2 and Ret were targeted with single sgRNAs, which were specifically designed to create indel mutations in these genes, and specific lentivirus vectors were produced with each guide. After transduction with the lentivirus vectors, survival of the TH-positive neurons was unaffected. Data obtained from the quantitative PCR suggested that there was 50-70% decline in transcript levels of Trbp. However, the unchanged transcript levels of the other miRNA-related targets suggest the need for further optimization of the specific guides. Knockdown of Ret was validated by inhibition of pharmacological benefits of GDNF. Overall, this research has shown the further development of this CRISPR-Cas9 tool would be useful to dissect neuroprotective signaling pathways in dopaminergic neurons.

This thesis explores the relationship between energy justice and demand response electricity pricing schemes in the residential market. As energy retailers make the transition towards demand response contracts, many opportunities arise for justice and injustice. It is vital that consumers are protected from arising injustices, and that the benefits of demand response schemes are distributed across the population. I use a popular energy justice framework to evaluate the demand response schemes of three European electricity retailers for their adherence to the principles of energy justice. The eight evaluative criteria are availability, affordability, due process, good governance, sustainability, intragenerational equity, intergenerational equity and responsibility. The three retailers are Tibber, E.ON Next, and Helen. Through this evaluation, I demonstrate that novel developments in energy systems by some energy retailers can positively inform the policies and practices of conventional retailers. There is room for growth in customer communication, stakeholder involvement, and smart home integration. My evaluation shows that retailers are yet to meet the aspirations of energy justice with their demand response schemes, but the potential for promoting justice clearly exists. I conclude with a set of recommendations Helen can take to meet the goals of energy justice in their electricity contracts.

The Seychelles magpie robin Copsychus sechellarum is among the most threatened of the twelve avian species endemic to Seychelles. Originally relatively abundant and widespread in Seychelles, its population has severely diminished, mainly on account of introduced predators and habitat destruction. The lowest count was recorded in 1965, when the number of birds was between eight and fifteen, all confined to just one island. In 1990 a successful recovery program was implemented, and the population has now recovered to approximately 150 birds on four islands. Translocations to new islands are a major part of the recovery program. So far Seychelles magpie robins have been translocated to three islands, and three more target islands still need to be chosen if the long-term goals of the project are to be reached. Determining habitat suitability at the translocation target area is essential before attempting a translocation. Cockroaches are a major part of the bird's diet. Cockroach abundance has been shown to be a good indicator of magpie robin habitat quality, but it is very laborious and time consuming to measure. The objective of this study is to build a model that can be used to predict cockroach abundance, and thereby Seychelles magpie robin habitat quality, with relatively simple and inexpensive measurements. The data for this project was collected on Cousin, Cousine and Aride islands in Seychelles during October and November 2004. Several potential predictors of cockroach abundance were measured using simple and low-cost methods. The measured variables were Seychelles skink Mabuya sechellensis abundance, altitude from sea level, slope gradient, rock type, canopy cover, shrub cover, litter depth, soil depth, the relative canopy cover of different tree species, and percentage of ground covered by litter, rock, grass, woody vegetation and bare ground. These variables were measured in several 25 × 25 m plots on each island. Cockroach abundance had been measured in the same plots previously. Several multiple linear regression models were built using these variables, with cockroach abundance as the dependent variable. The Akaike Information Criterion was used to rank the models and to find the most important explanatory variables. Stepwise regression was used as a secondary method in order to see if two different methods point to the same result. Both methods indicated that slope gradient and granitic rock type are the two most important predictors of those tested. These are features that are invariably associated with granitic terrain, and both are positively correlated with cockroach abundance. A simple comparison of average cockroach abundance between granitic and coralline rock types also showed a significant difference, with granitic terrain providing higher cockroach abundance. The islands in Seychelles can be divided into two main categories: granitic and coralline islands. Steep slopes and granitic rock are both features associated with granitic terrain and granitic islands only. Therefore, based on the results of this study, granitic islands are likely to provide higher cockroach abundance and thus better Seychelles magpie robin habitat quality. Hence it is recommended that Seychelles magpie robin translocation efforts are focused preferentially on granitic islands.

Not much attention is paid on the conservation of invertebrates despite their importance to the ecosystems in general and their benefits and ecosystem services to us, humans. This study is part of a project aiming to start the Sampled Red List Index (SRLI) for spiders. The IUCN Red List Index (RLI) is used for measuring the overall extinction risk of groups of species and the sampled approach is a way to evaluate the trajectory towards extinction of megadiverse groups without the need to assess every species of the whole group of interest. A random sample of 200 spider species were selected from the global checklist and assessed according to IUCN Red List Categories and Criteria. Given the availability of data, I was able to calculate the extent of occurrence and area of occupancy for 80 species, of which 70 species had an EOO above 20000 km² and 75 species an AOO above 2000 km², the thresholds below which species can be considered threatened. The trends in EOO and AOO were assumed to be stable for most species (49 species) given the inexistence of monitoring data for any taxon. Evidence of decline was found for only 10 species, usually inferred from habitat loss. Habitat data was collected for 118 species. The most common habitat type was forest (73 species), followed by grasslands (24 species) and artificial habitats (22 species). For 44 species the habitat trend was inferred to be stable, only declining, according to available knowledge, for 14 species and increasing for one species. For the remaining 141 species the habitat trend could not be inferred and was thus assumed to be unknown. The most commonly mentioned threat types were agriculture (11 species), fires (7 species) and logging (6 species). For 39 species there were no known threats and for the rest of the 132 species the threats were unknown. Conservation actions in place were observed for 104 species, most commonly site and area protection (100 species) and resource and habitat protection (88 species). Conservation actions such as education and awareness (8 species), resource and habitat protection (7 species) and site and area management (6 species) were to take into consideration. All the 200 species were estimated to be in need of further basic research especially on threats (143 species and distribution (140 species), but also on life history and ecology (135 species). Due to several knowledge shortfalls, including the Wallacean (distribution of species), Prestonian (population trends) and Hutchinsonian (response to environmental change), no threat category could be reached for the vast majority of the species. The results show that an IUCN category could be reached for only 59 species, of which 55 were assessed as Least Concern and a threatened category was reached for only 4 species (t as Critically Endangered and one as Vulnerable). The baseline SRLI at this first point in time was 0.95 (in a 0-1 scale, where 0 means all species are extinct and 1 for all species are Least Concern). We hypothesize however that among the 141 Data Deficient species there should be a higher proportion of threatened species than among the 59 evaluated. This would be due to two reasons. First, the scarcity of information on many species might in part be due to their rarity. Second, widespread species were often the only for which an assessment could be reached, creating a bias in the dataset towards a large base SRLI value. The strategy currently imposed by IUCN is therefore clearly inadequate for taxa with scarce information, which represent the vast majority of species. I propose the future use of a different, non-random, approach to the selection of species in the SRLI and its adoption for other taxa which represent in fact most extant and threatened species.

Urban greenspaces are valuable resources for humans and are an integral part of the urban landscape. They are also popular sites for various social and cultural activities, such as dog walking. Dog ownership rates are increasing globally at a rapid rate, hence increasing the dog populations within urban cities. The increasing number of dogs could potentially have negative consequences to the quality of urban parks. Furthermore, there is a lack of research on the impacts of dogs on urban environments. The aim of this study is to gain a better understanding of the impacts of dogs on path-side soils in urban greenspaces. Soil samples were collected from both Helsinki and Lahti. The impact of dog urine was studied by comparing path-side soil samples between areas with high dog activity (i.e., parks) and similar areas with low to no dog activity (i.e., cemeteries). Soil samples were collected three times during the growing season in 2021 at three different treatments: close by 1) an evergreen tree, 2) a lamppost, and 3) a lawn area. The samples were analyzed for soil pH, electrical conductivity, organic matter, soil moisture, NO3--N, and NH4+-N. Net N mineralization and net nitrification rates were also calculated. The results indicated that dog urine is a significant contributor to the input of nitrogen in urban parks. Soil NO3-N and NH4+-N concentrations were significantly higher in parks than in cemeteries and exhibited clear seasonal trends. Soil pH was generally lower and electrical conductivity higher in parks than in cemeteries. Poles and trees exhibited the greatest concentrations, suggesting that the impact of dog urine is highly localized around path-side objects. None of the treatments in cemeteries showed little to no changes throughout the growing season. Lastly, the net nitrification rates were significantly higher in parks during spring and summer. In contrast, net mineralization rates were generally higher in cemeteries than parks. These results confirm that urban planners need to take into consideration the impact of dogs to mitigate any potential negative consequences to the quality of urban parks.

Kaurapohjaiset elintarvikkeet ovat terveellisiä. Monet niiden terveyshyödyt johtuvat kauran liukoisen ravintokuidun suuresta β-glukaanipitoisuudesta. β-glukaanin terveysvaikutukset ovat riippuvaisia sen molekyylipainosta ja viskositeetista. Viskositeetilla on myös muuta merkitystä kaurapohjaisissa elintarvikkeissa kuten kaurajugurteissa ja kauramaidoissa. Aiemmassa Folafibre-tutkimusprojektissa oli tutkittu kaurakuidun folaattipitoisuuden (B9 vitamiini) kasvattamista fermentoimalla sitä eri mikrobeilla. Hyvin folaattia tuottaneet mikrobit myös alensivat kaurakuituvalmisteen viskositeettia, ja erittivät glykosyylihydrolaaseja ja/tai proteaasia. Oli kuitenkin jäänyt epäselväksi, olivatko entsyymit ainut syy viskositeetin alenemiseen, ja kuinka paljon kullakin niistä oli vaikutusta viskositeettiin. Lisäksi tämän alan kirjallisuudessa on pidetty epäselvänä, onko esim. tärkkelyksen ja β-glukaanin välillä jotain interaktioita jotka mm. nostavat niiden viskositeettia yli yksittäisten polymeerien viskositeetin summan. Näitä voitaisiin selvittää puhdistamalla viskositeettia alentaneista mikrobikannoista kyseiset entsyymit ja tutkimalla niiden vaikutusta kaurakuidun viskositeettiin. Yhdeksi mikrobiksi valittiin Exiguobacterium sp. RB3 kanta, koska em. syiden lisäksi tässä bakteerisuvussa esiintyy psykrofiilejä ja mikrobeja jotka voivat kasvaa korkeassa pH:ssa, jolloin sen erittämät entsyymit saattaisivat olla aktiivisia matalissa lämpötiloissa ja korkeassa pH:ssa, ja olla siten teollisesti kiinnostavia. Toiseksi mikrobiksi valittiin Bacillus sp. ABM5119, koska sitä oli käytetty monissa Folafibre-projektin tutkimuksissa. Työn tavoitteena oli puhdistaa Bacillus sp. ABM5119:n endo-β-1,4-glukanaasi, ja Exiguobacterium sp. RB3:n α-amylaasi ainakin siinä määrin, että ne ovat muista endoaktiivisista glykosyylihydrolaaseista ja proteaaseista puhtaita, ja sitten mitata puhdistettuja entsyymejä ja proteaasia käyttäen niiden vaikutus yhdessä ja erikseen keitetyn kaurakuituvalmisteen viskositeettiin. Lisäksi tavoitteena oli karakterisoida Exiguobacterium sp. RB3 amylaasin olennaisimmat biokemialliset ominaisuudet, sekvensoida sen geenin amylaasia koodaava alue, ja selittää sen ominaisuuksia myös sekvenssistä johdettavissa olevan tiedon perusteella. Keitetyn kaurakuitupreparaatin viskositeettia alentavat eniten α-amylaasi ja endo-β-1,4-glukanaasi. Proteaasi ei vaikuta kaurakuitupreparaatin viskositeettiin, kun kuitupreparaatti on keitetty. Endo-β-1,4-glukanaasi alentaa viskositeettia yhtä hyvin kuin β-1,3-1,4-glukanaasi. Synergiaa viskositeetin alentamisessa α-amylaasilla ja endo-β-1,4-glukanaasilla ei havaittu, mutta havaittiin että β-glukaani saattaa estää tärkkelyksen retrogradaatiota. Hyvin pienetkin entsyymiaktiivisuudet vaikuttavat viskositeettiin. Jos halutaan β-glukaanin viskositeetin ja siten terveysvaikutusten säilyvän, täytyy esim. kauramaidon valmistuksessa käytettävien entsyymivalmisteiden olla β-glukanaaseista hyvin puhtaita. Mikrobifermentaatioissa tapahtuvat viskositeetin alenemat johtuvat lähinnä mikrobien erittämistä glykosyylihydrolaaseista, ei niinkään esim. niiden metabolian sivutuotteista kuten happiradikaaleista. Exiguobacterium sp. RB3 α-amylaasi on rakenteeltaan Bacillus licheniformis α-amylaasin kaltainen glykosyylihydrolaasiryhmän 13 entsyymi. Se sitoo rakenteeseensa kolme kalsiumiatomia, ja kalsiumpitoisuus vaikuttaa sen aktiivisuuteen. Se on aktiivisimmillan pH alueella 5,0 – 7,5. Se sietää detergenttejä, toisin kuin eräs aiemmin karakterisoitu Exiguobacterium-α-amylaasi. RB3 α-amylaasin turnover number oli korkea, 29000 1/s. Exiguobacterium-suvun psykrofiilisessä haarassa esiintyy kahta eri α-amylaasia, joista yksi on tässä karakterisoitu, ja toinen on selvästi erilainen rakenteeltaan ja biokemiallisilta ominaisuuksiltaan.

In recent years, the science community has increasingly emphasized the influence of behavior, lifestyles, and culture on greenhouse gas emissions. Finland’s emissions per capita (~10 tCO2/yr.) are amongst the highest in the world, and it has been calculated that to comply with the Paris Agreement and to limit global warming to well below 2 °C, Finnish households should reduce their carbon footprint by 70 % by 2030. This requires drastic lifestyle changes, especially regarding mobility, housing, and nutrition. However, knowing this is not enough to change behaviors. Human behavior is influenced by several different internal and external factors such as knowledge, values, and social structures. This master’s thesis is a case study conducted in the Environmental Change and Global Sustainability (ECGS) master’s program at the University of Helsinki with the aim to enrich theories about pro-environmental behavior by providing insights on the future aspirations of sustainability science students, who have both extensive knowledge and experience in the field of sustainability. The data for this study was collected through an anonymous, online questionnaire with four open-ended questions. In total, 61 out of 274 ECGS students answered the questionnaire, after which qualitative content analysis with both inductive and deductive elements was applied to analyze the results. The results confirm that ECGS students are indeed well aware of the most impactful lifestyle changes for reducing personal carbon footprint. Despite their extensive knowledge on sustainability, the students’ future aspirations still come quite close to the dominant cultural vision of a good life in Finland. The implications of these findings once again confirm the importance of facilitating sustainable ways of living through changes in societal structures, discourses, and norms.