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(2023)The lymphatic system is a network of vessels that permeate a substantial part of the whole body. It plays an essential role in fluid homeostasis by the drainage of interstitial fluid from the blood capillaries, after which the fluid, now called lymph, is transported through the vessel network and back to the blood circulation. The lymphatic system also plays an important role in the transportation of immune cells and in activation and maintenance of the immune system. Due to these crucial functions, there is a growing interest in exploiting the lymphatic system in the treatment of many immunological and inflammatory diseases. In many cases, an ideal treatment method would be to induce lymphatic growth (lymphangiogenesis) to boost immunological functions, facilitate resolution of inflammation and reduce the harm from lymphatic vascular abnormalities. However, there is a gap in knowledge in how to induce lymphangiogenesis in a controlled manner, with the major lymphangiogenic growth factor, vascular endothelial factor C (VEGF-C), tending to create disorganized lymphatic networks. The purpose of this thesis is to investigate factors influencing lymphangiogenesis, in an attempt to find ways to control it. Vaahtomeri research group has preliminary results showing a role of planar cell polarity (PCP) in control of dermal lymphatic vessel sprouting (the initial step for the formation of new lymphatic branches) and lymphatic network expansion. The focus of Vaahtomeri research group has been the core PCP protein Van Gogh-like protein 2 (VANGL2), which together with the other core PCP proteins is known to play an important role in the collective cell polarization and morphogenesis in many tissue types. The role of VANGL2 has previously been studied in the lymphatic system, and so far, VANGL2 has been implicated in both lymphatic valve morphogenesis and in flow-induced control of lymphatic endothelial cell (LEC) polarization. However, there still remains a gap in knowledge in what role VANGL2 plays in lymphangiogenesis and the lymphatic network as a whole. In this thesis, I investigated the role of VANGL2 in lymphangiogenesis, firstly by the use of an in vivo lymph node experiment, which offered a robust model to investigate the role of VANGL2 in the mature lymph node lymphatic network. In the experiment, I induced growth of the lymph node lymphatic network by means of an immunization reaction, and then I compared the lymphatic networks of Vangl2-deleted and control mice. Despite some minor differences between the Vangl2-deleted and control lymphatic networks, this experiment did not show a role for VANGL2 in the mature lymph node lymphatic network. Secondly, I investigated the potential mechanistic role of VANGL2 in control of dermal lymphatic vessel sprouting in growth conditions. This experiment showed a specific role for VANGL2 in sprouting of the lymphatic network, thus providing valuable research in understanding how lymphangiogenesis is regulated. Altogether, the results presented in this thesis work as a steppingstone for finding new treatments relating to the safe induction of lymphangiogenesis.
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(2023)Climate change and its unparalleled and irreversible effects to natural and human systems initiate a need to take immediate action to develop effective measures for climate change adaptation. Both climate change impacts and responses to climate change are found to further aggravate the division between winners and losers that is already present in the pre-existing patterns of development. This is while previous research has found explicit concern for justice to be limited at the urban level. This study seeks to examine urban climate change adaptation strategies critically from the perspective of climate justice to contribute to the understanding of how justice can be identified and advocated for in practice. Justice is conceptualised with four justice dimensions encompassing recognitional, distributive, procedural, and restorative justice dimensions. An Adaptation Justice Index is applied to policy documents to perform a qualitative content analysis. In addition, a literature review is utilised to explore the representations of justice present in the adaptation strategies of eight leading city-level climate change adaptors. Results from the analysis show that on average, procedural justice dimension is the most highlighted among the four dimensions, while restorative justice is the least emphasised. The cities performed the best in allocating responsibilities related to adaptation and in enabling participation in the implementation phase. Strategies frequently emphasise vulnerable people and acknowledge the aim to advance equity and just outcomes with adaptation initiatives. The initiatives described in the strategies, however, seem generally to be insufficient to realise these outcomes. Measures to include the perspectives of vulnerable individuals and communities are found to require improvement to promote empowerment of disadvantaged people for climate justice. The impacts of adaptation measures ought to be scrutinised in more detail to recognise the losses borne by the most disadvantaged in society and to make amends for injustices taking place in the context of climate change and adaptation practice. In conclusion, more research is in order to shed further light to the extent climate justice is accounted for in adaptation practice, especially in the context of the Global South.
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(2023)Metsätalouden seurauksena lahopuu on vähentynyt Suomen metsissä ja siten useat lahopuusta riippuvaiset lajit ovat päätyneet uhanalaisiksi. Lahopuun määrän lisäämiseksi metsähakkuiden yhteydessä on alettu jättämään säästöpuita ja tekopökkelöitä. Tekopökkelöt hyödyttävät lahotessaan lahopuusta riippuvaisia lajeja, kuten kolopesiviä myrkkypistiäisiä. Kolopesivät myrkkypistiäiset rakentavat pesänsä yleensä kovakuoriaisten puiden runkoihin kaivamiin koloihin. Tässä tutkimuksessa selvitettiin, millaista myrkkypistiäislajistoa tekopökkelöt tukevat, millaiset ja miten sijoitetut tekopökkelöt ovat hyödyllisimpiä myrkkypistiäisille, onko tekopökkelön vai ympäristön laatu merkittävämpää myrkkypistiäisille ja eroavatko eri ekologisten ryhmien (mesipistiäiset, petoina elävät myrkkypistiäiset ja pesäloiset) myrkkypistiäiset pesäpaikkavaatimuksiltaan. Tutkimuksen aineisto kerättiin kesällä 2021 Keski-Suomessa Viitasaarella, kuusivaltaisilta eri tavoin käsitellyiltä metsäkuviolta. Kuvioista kahdeksan oli harvennuksia, tuoreita päätehakkuita kahdeksan ja vanhoja päätehakkuita kymmenen. Tekopökkelöiden myrkkypistiäislajistoa tutkittiin keinopesien avulla. Keinopesät koostuivat muoviputkilosta, jonka sisällä oli eri kokoisia järviruo’on (Phragmites australis) korsia, monenlaisten myrkkypistiäislajien houkuttelemiseksi. Keinopesiä kiinnitettiin yhteensä 120 kappaletta teko- ja luonnonpökkelöihin, sekä kantoihin. Puulajeina oli kuusi ja koivu, sekä yksi haapa. Pökkelöistä ja metsäkuvioilta mitattiin niiden laatua kuvaavia muuttujia. Keinopesät olivat maastossa keväästä syksyyn, jolloin ne haettiin säilytykseen ulkovarastoon. Keinopesät siirrettiin huoneenlämpöön alkuvuonna 2022 pistiäisten aikuiseksi kehittymisen vauhdittamiseksi. Korret avattiin ja aikuiset myrkkypistiäiset tunnistettiin pesittäin lajilleen mikroskooppia apuna käyttäen. Tilastolliset analyysit suoritettiin R-Studiolla. Yksilö- ja lajimäärän muutoksia suhteessa selittäviin muuttujiin arvioitiin yleistetyillä lineaarisilla sekamalleilla (GLMM). Selittävinä muuttujina toimivat lämpötila, pökkelön korkeus, kaarnan peittävyys, alustan tyyppi, puulaji, lahopuun määrä, ravintokasvien määrä, hakkuutyyppi, pökkelön sijainti ja pesäkolojen määrä. Myrkkypistiäislajiyhteisöjen erilaisuutta arvioitiin NMDS-analyysillä. Sen avulla havainnollistettiin lajiyhteisöjen erilaisuutta eri hakkuutyyppien välillä. Keinopesistä löydettiin kolopesiviä myrkkypistiäisiä ja niiden myrkkypistiäispesäloisia yhteensä yli 3000 yksilöä. Petoina eläviä myrkkypistiäisiä löytyi eniten harvennusmetsistä, joissa oli alhaisempi lämpötila kuin tuoreilla ja vanhoilla päätehakkuilla. Mesipistiäisiä, jotka ruokailevat sekä toukka että aikuisvaiheessa medellä ja siitepölyllä, löytyi eniten tuoreilta ja vanhoilta päätehakkuilta. Näillä kuvioilla oli korkeamman lämpötilan lisäksi aurinkoisempaa ja enemmän ravintokasveja kuin harvennusmetsissä. Kaikkia myrkkypistiäisiä löytyi eniten korkeilta pökkelöiltä, joiden rungoilla oli vain vähän kaarnaa. Myrkkypistiäiset suosivat enemmän teko- ja luonnonpökkelöitä kuin kantoja. Pökkelön ympäristön ominaisuudet olivat kuitenkin tärkeämpiä kuin pökkelön ominaisuudet niin lajimäärälle kuin yksilörunsaudelle. Koska eri ekologisten ryhmien lajit suosivat erilaisia elinympäristöjä, tekopökkelöitä kannattaa jatkossakin tehdä sekä pääte- että harvennushakkuiden yhteydessä. Tekopökkelöitä tehdessä kannattaa myös huomioida niiden monipuolinen sijoittuminen reunoille ja keskelle hakkuuta, jotta niitä jää hakkuualueelle monenlaisiin ympäristöoloihin. Tekopökkelö tulisi katkaista mahdollisimman korkealta, sillä korkeisiin pökkelöihin mahtuu enemmän pesiä kuin mataliin ja matalat pökkelöt ovat alttiimpia kosteudelle, sekä pesien homehtumiselle kuin korkeat pökkelöt.
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(2023)Non-native species can have complex effects on the abundance of native species potentially altering the functioning of ecosystems negatively. Invasive species can outcompete local species competing for resources, ultimately causing the extinction of local species. Inter- and intraspecific competition can be especially vigorous for limited resources. Invasive species have been thought to be a leading cause in native species extinction, and their effects on native species can be especially pronounced during reproductive crucial life-history stages, such as nest-building. Based on previous information about invasive species and their effects on ecosystems, and previous studies conducted related to invasive species, I conducted an experiment at the Tvärminne zoological station in Hanko, southern Finland during May and June of 2021. I conducted a laboratory experiment in which the test species used were the invasive fish species round goby, that has increased its range across the Baltic Sea rapidly, and the native fish species sand goby. The purpose was to see, if there was any effect the invasive species has on the nesting success and motivation of the native species. Methods included five different treatments in aquariums. The results did not differ statistically between different treatments, length was close to statistical significance. However, these results do not demonstrate, that the round goby has no effect on the nest building motivation of sand gobies. Some factors of the experimental setup might have been faulty, and future studies with a larger sample are needed to examine the effects of competition on native species’ abundance.
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(2023)Climate change severely threatens ecosystem services and human well-being: vegetation and soils underneath it can be particularly vulnerable to climate warming. Soils hold the largest carbon stock in terrestrial ecosystems, and urban park soils, especially in cool climates, can hold remarkable carbon stocks and may be able to offset some atmospheric CO2 emissions. Land use changes, such as urbanization, influence soil organic carbon formation and soil carbon storages. In this study, I was interested whether three vegetation types (deciduous trees, conifers and lawn) differ in their capacity to store C in their rhizosphere, and whether this is affected by park size. I measured the proportion of tree canopy layer in class A park areas of the city of Helsinki, to estimate soil C storages of these areas and to examine C density (kg C m-2). Proportions of tree canopy layers in different park size groups were measured using QGIS and ortographs. Soil C storages were calculated using existing soil C data and average proportions of conifer and deciduous trees in parks of the city of Helsinki. Park size had a significant effect on proportion of the tree canopy coverage: canopy cover decreases with an increase in park size. Especially large parks are dominated by lawn. The average soil C densities in small, medium and large parks were 23.98 kg C m-2, 23.47 kg C m-2 and 23.15 kg C m-2, respectively. However, the overall proportion of conifer canopy in parks of the city of Helsinki is rather small, resulting in small differences in C densities between different park size categories, despite significant differences in tree canopy coverage between the three size groups. Most of the stored soil C in parks of the city of Helsinki are under lawn, even though it is the least efficient of the three studied vegetation types (deciduous trees, conifers, lawn) in soil C sequestration. Within a park size category and at park level, large parks store the highest amount of carbon per park. Even so, at the city level, the total amount of carbon is highest in the small parks due to their high number. Conifer trees associate with improved C sequestration to soils compared to deciduous trees and lawn. Increasing the amount of conifer trees in urban parks thus likely increase the important C storages of these soils. Results of this study highlight the importance of the contribution of urban parks and especially conifer trees in carbon sequestration. Future research related to urban soil C sequestration and the effects of vegetation type and climatic conditions is needed to better understand soil C accumulation and how the C sequestration of urban park soils could be enhanced.
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(2023)Research into animal emotions is important for improving animal welfare and understanding behavior. Emotional research also provides a better overview of ecology and helps from the point of view of protection. According to the consensus, animals feel different emotions and express their feelings in many ways. Emotional expression is also an important part of communication between animals. In my research, I wanted to study zoo visitors’ ability to interpret animals’ emotions. The study was conducted in Korkeasaari as a survey, where respondents were asked to rate animals’ valence and arousal based on short video clips. According to several theories, valence and arousal are two important dimensions of emotion. Interpretation is based on movements, expressions, and gestures of one animal or several animals. In my research, I used videos of Barbary macaque, Siberian tiger, and Markhor expressing different emotions. The aim of this study was to explore if there are differences in participants ratings between the species. In addition, I explored whether a specific emotion is interpreted better than others. I expected that, based on an evolutionary distance, the emotions of the Barbary macaque would be interpreted best despite the emotion. Secondly, I expected the best identification of negative Valence and high arousal, which would be important for evolution and survival. I found that the valence of the barbary macaque was interpreted best, but the arousal of the markhor was interpreted as well as the Barbary macaques. Different emotions were interpreted differently in each specie. The interpretation of emotions is also influenced by the participant’s demographic factors such as age and gender. Differences in ratings between the species may also be explained by species-specific factors such as the extent of the emotional scale to be expressed or need to express emotions. Together with other similar studies, the aim of this study is to improve animal welfare and to increase interest and knowledge of animal emotions.
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(2023)The intestinal stem cells (ISCs) adapt in response to environmental factors and continually proliferate to renew the mammalian intestinal epithelium due to its rapid turnover. Overall, intestinal homeostasis is maintained by the differentiation and self-renewal of ISCs, which are regulated by different mechanisms, including epigenetic histone modifications. Earlier studies in the host laboratory have shown that the histone methyltransferase Su(var)3-9 is essential in the nutrient-induced activation of intestinal stem cells. Su(var)3-9 specifically trimethylates histone H3 on lysine 9 (H3K9me3), which is a repressive histone mark, responsible for transcriptional silencing at heterochromatin regions. It influences stem cell maturation, lineage specification, and many other cellular processes. However, the precise mechanisms behind its function in ISCs remain unknown – that knowledge is important for understanding the development of many diseases, including cancer and metabolic disorders. This thesis aimed to investigate the distribution of the heterochromatin mark H3K9me3 in the intestine with an emphasis on ISCs, using the Drosophila midgut and mouse intestinal organoids as models. Confocal microscopy was used together with cell-type-specific fluorescent staining, to obtain the expression of the H3K9me3 specific histone methyltransferase Su(var)3-9, in the midgut. An antibody was used for the detection of H3K9me3 distribution along the anterior/posterior axis in Su(var)3-9 overexpressed flies. Additionally, DNA adenine methyltransferase identification (DamID) was applied in order to find target genes of the H3K9me3 regulation in the genome with the specific chromo domain of M-phase phosphoprotein 8 (MPHOSPH8) that binds to H3K9me3. The number of lineage-labeled differentiated enterocytes was shown to be locally higher in the Su(var)3-9 overexpressed flies compared with the control, although the flies were on starvation without nutrient-induced activation. Moreover, the number of lineage-labeled progenitor cells was not remarkably altered between the samples. However, the intensity of H3K9me3 was significantly higher throughout the whole midguts in the Su(var)3-9 overexpressed flies in comparison to the control. According to one replicate, the DamID in mouse intestinal organoids revealed that the peaks of H3K9me3 were divergent between the samples grown in different conditions. The first sample was assumed to contain more ISCs, whereas the other one was assumed to contain more differentiated intestinal cells. According to my results, the Su(var)3-9 overexpression drives the stem cells against the differentiation of enterocytes. Furthermore, the MPHOSPH8 chromo domain in the organoids was successfully applied in DamID; thus, more replicates should be prepared for additional analysis, because I found several potential target genes of H3K9me3. In the future, it is important to further study the epigenetic regulation of ISCs, for applying the epigenetic marks as targets for the treatment of many human pathophysiological conditions, such as cancer, obesity, and metabolic disorders.
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(2023)Global warming should not rise beyond 1.5°C, which means that all sectors in the economy are needed to reduce greenhouse gas emissions. The need for corporations to account their value chain emissions has sprung a variety of accounting and reporting standards. In response, Greenhouse Gas protocol established the Corporate Value Chain (Scope 3) Accounting and Reporting Standard. However, the success of the scope 3 emission accounting has been determined to be insufficient. The unsuccess of scope 3 emission accounting and reporting can be explained with the challenges that have been widely identified. Nevertheless, the identified challenges do not provide a deeper understanding of why they hinder the success of scope 3 accounting and reporting. This thesis delves into the challenges of scope 3 accounting by investigating four Finnish food industry corporations. The study for this thesis was conducted as semi-structured interviews of seven experts who work with the scope 3 accounting and reporting of their corporation. The interviews were held in May of 2022 and theory guided thematic analysis was used to analyze the results. The results show that there are challenges concerning measurement and evaluation, knowledge and guidance and communication. The measurement and evaluation challenges include data collection challenges, data quality challenges and data processing challenges. The key finding from this study is that most of these challenges are highly connected. The reporting corporation and suppliers’ resources and guidance play a key role in data collection and how accurate data can be obtained for the GHG inventory. These affect the comparability of gained emission factors and how comparable the emission information of products, production lines and corporations are. The findings of this study share understanding of the complexity of scope 3 accounting challenges.
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(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.
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Attitudes and perceptions of Nature-based solutions : A case study in Kuninkaantammi and Kalasatama (2023)Luontopohjaiset ratkaisut (NBS, Nature-based solutions) ovat tietoisesti suunniteltuja ratkaisuja komplekseihin haasteisiin, ja niiden ytimessä ovat ”luonnon” elementit, kuten valikoidut mikrobit ja kasvillisuus. Nämä elementit ovat luontopohjaisen ratkaisun ytimessä, ja näin tekevät NBS:stä usein ekologisesti kestävämmän vaihtoehdon perinteisille teknisille maisemaratkaisuille. Suuri osa olemassaolevasta kirjallisuudesta on siten keskittynyt NBS:n ekologiseen ulottuvuuteen huolimatta niiden sisäsyntyisestä moniulotteisuudesta. Sosiaaliset elementit ovat kuitenkin paitsi olennainen osa NBS:n suunnittelua ja toimintaa, myös niiden pitkän tähtäimen onnistumisen edellytys. Aiempi tutkimus on osoittanut, että luontopohjaisten ratkaisujen menestys riippuu ennen kaikkea niiden paikallisen yhteisön saavuttamasta yhteydestä ja omistajuudesta. Näiden suhteiden muodostuminen tapahtuu usealla tasolla, mukaan lukien psykologisella ja asuinaluetasolla. Siksi tämä tutkimus tarkastelee luontopohjaisiin ratkaisuihin yhdistettäviä merkityksiä ja näkemyksiä paikallisen, karttapohjaisen, audio-visuaalisen kyselyn kautta. Vastauksista nousee esiin kaksi primääristä huomiota: Ensiksi, aineistosta on mahdollista erottaa NBS- ja äänimaailmamieltymysten, sekä avointen paikan merkitysten pohdintojen kautta vähintään kaksi paikallista arkkityyppiä, jotka lähestyvät luontopohjaisia ratkaisuja uniikeilla tavoilla. Toiseksi, erot näiden arkkityyppien reaktioissa paikallisiin luontopohjaisiin ratkaisuihinsa voivat selittyä osin luontosuhteen ja paikallishistorian kautta. Nämä löydöt korostavat yhtäältä olemassaolevan henkilökohtaiseen psykologiseen ulottuvuuteen keskittyvän NBS-tutkimuksen merkitystä, ja toisaalta paikallisen ja yhteisötason ymmärrystä kokonaisen
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(2023)Adolescent ill-being has in recent years become a prominent health concern globally. Ill-being during adolescence can have negative consequences for future health and wellbeing, as important patterns of health are formed during this time. This highlights the importance of early identification of risk factors and overarching patterns of mental and physical ill-being and arguments for early intervention during adolescence. The aim of this study was to identify risk factors and co-occurrence of subjective ill-being symptoms in the form of depressive symptoms and subjective health complaints. This study also examined whether the subjective ill-being of students was reflected in cortisol patterns in a naturalistic setting. This since stress has been identified as a key etiological factor in ill-being, through the damaging effect of prolonged exposure to elevated cortisol levels. By applying a novel measure of school atmosphere, the study also aimed to examine the potential protective role of the social atmosphere in school on subjective ill-being and cortisol levels. A total of 329 students from eleven Finnish-Swedish upper secondary schools participated in the cross-sectional study by answering a questionnaire. The salivary cortisol samples were collected from a subsample of the participants, with of a total of 209 participant that met the salivary sampling criteria applied in the study. The methodological framework for the statistical analysis of the study consisted of independent samples t-test, ANOVA, Pearson’s correlation, and multiple linear regression. The results showed a higher prevalence of ill-being in girls and second year students. A significant co-occurrence was found for the subjective ill-being measures of depressive symptom and subjective health concerns. The subjective ill-being was however not reflected in the daily cortisol patterns of students in a naturalistic setting. Furthermore, a positive school atmosphere was significantly negatively associated with subjective ill-being of student in the form of depressive symptoms and subjective health complaints. When controlling for covariates, the subjective meaning of school experienced by the students was identified as a significant protective factor against symptoms of ill-being. These findings identify students in need of additional support and highlights the need of applying an overarching view on student ill-being in future adolescent research. Since no associations was found between daily cortisol patterns and subjective ill-being this study contributes to the understanding of HPA axis in early disorder onset. This study also highlights the importance of subjective meaning in a school context and posits increasing the subjective meaning as a prominent strategy to decrease ill-being among Finnish-Swedish upper secondary school students. Further studies are however needed to assess the causality and to examine these relationships further.
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(2023)Normal sex differentiation depends largely on the healthy development of the bipotential gonad, which is identical in both sexes during early stages of embryonic development. Sex differentiation towards the female phenotype is initiated by the expression of pro-ovarian genes, among which Forkhead Box L2 (FOXL2) is an important regulator. Moreover, FOXL2 was found to be one of the genes most widely implicated in female disorders of sex development (DSD). However, there is a lack of understanding regarding its precise role during ovarian differentiation and development. In order to study the gene during early gonadal development, human embryonic stem cells (hESCs) were used as a model. An inducible FOXL2 activation line was generated in vitro, by applying the CRISPR/Cas9 technique in combination with the tetON and destabilized DHFR systems. The cells were also subjected to gonadal differentiation, based on a previously established protocol. The results showed that the establishment of the activation line was successful, and expression of FOXL2 could only be observed in cells that were treated with trimethoprim and doxycycline. Similar findings were observed in the differentiated activator cells, as again only the induced cells expressed FOXL2. On the other hand, both induced and non-induced differentiated cells showed expression of bipotential gonadal marker genes LHX9, EMX2, GATA4 and WT1. However, in the induced cells a lower relative expression of these markers could be observed. Therefore it seems that relative expression of bipotential gonadal markers was affected by FOXL2 activation. The expression of female gonadal marker genes RSPO1, FSHR, WNT4, AMH and FST was not influenced by FOXL2 activation during gonadal differentiation, as most of the markers showed similar levels of expression in both induced and non-induced cells. Therefore further research needs to be conducted to determine optimal time point of FOXL2 activation during differentiation. Nevertheless, an in vitro model could be generated, which could help in the future to further study the role of FOXL2 in gonadal differentiation, and to better understand pathological mechanisms underlying female DSDs.
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(2023)The anthropause following the beginning of the COVID-19 pandemic in 2020 was followed by a heavy decline in people’s mobility and outdoor activities, which has had differing effects on biodiversity in urban areas. In Finland, outdoor activities were allowed, and as a result, the use of greenspaces increased notably in relation to pre-pandemic times. My objective was to study how people’s outdoor activities developed during the pandemic in the form of recreational bird-watching in the Helsinki metropolitan area (including Espoo, Vantaa, and Kauniainen). To accomplish this, I retrieved data on the number of bird observers from Tiira (a Finnish bird information service focused on bird observations), and related this data to the pandemic periods, also taking into account variables such as daily temperature and the use of parks. I found the highest number of bird-watchers during both lockdowns in 2020 and 2021. I also found that the number of bird-watchers was significantly higher after all restrictions were lifted, in 2022, when contrasted with pre-pandemic times. It is notable that the lockdowns happened at the same time as the bird Spring migration, a naturally popular time among bird-watchers. Thus, I consider that this may have had a synergistic role in people taking the opportunity to dedicate more time for bird-watching since they had more time to go outside due to strict restrictions. After all the restrictions were lifted in 2022, some bird-watchers continued to spend more time in bird-watching due to habit or increased appreciation for the activity or outdoors. The findings highlight the importance and potential of citizen science in observing birds and enabling more efficient conservation efforts for them. The results showing the development of bird-watching activities during the pandemic could also potentially be used as a proxy for other outdoor activities, and combined with other studies on the relations of COVID-19 on humans and other species could help to better understand the complex socio-ecological relationships in cities and greenspaces.
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(2023)Tiivistelmä - Referat - Abstract To aim for a just and sustainable society, it is essential to consider how we manage cities and to reflect on the role of young people as agents for successful future generations. The school system must take on the responsibility of developing a sense of social justice amongst young people. However, few learning activities are established to promote learning about environmental and intergenerational justice issues, and are usually limited to a top-down approach based on STEM disciplines (Science, Technology, Engineering and Mathematics). In this work, I argue that education in sustainability needs to be opened to a relational approach that introduces new justice perspectives, becoming a driver for active citizenship and public participation. The thesis is based on ten workshops conducted in Kumpula, Helsinki, involving 197 students from two upper secondary schools. The novelty of this work consists in addressing a specific range of upper secondary school students (16 to 19) and combining cognitive and relational learning activities to elicit reflections on environmental justice. I used a learning activity based on a Role-play method to actively involve students in working with justice perceptions and nature-based solutions. The analysis is based on a mixed methods- approach where the statistical analysis (pretest-posttest) and qualitative content analysis support each other. The innovative integration of cognitive and relational learning contributed to a deeper knowledge of urban green space management. This approach elicited new recognition justice perspectives by enhancing the participants’ awareness of community values and needs, comprehending both humans and non-humans. After the learning activity, students were generally more willing to make their voice heard by policy makers and to participate in public discussions. Based on the findings, more resources and time would be needed to build a long-term project in order to assess the permanence of relational and cognitive learning and more widely the efficacy of this approach for transformative learning.
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(2023)Good understanding of animal emotions is vital for improvement of animal welfare. Emotions are affective states that are defined by positive or negative valence depending on the pleasantness of the situation, as well as the state of arousal or excitement. As subjective experiences, emotions are hard to measure directly. Lateralization, a phenomenon in which emotion processing is done asymmetrically in different hemispheres of the brain, has been used to study changes in valence. The state of arousal is known to cause changes in the activation of the autonomic nervous system, which lead to changes in peripheral blood circulation. These neurologically mediated changes in blood flow can lead to changes in surface temperature that can be detected by infrared thermography (IRT). IRT is a technology that’s based on converting infrared radiation to images. From these images, the surface temperature of an animal can be quantitatively measured. Previous studies have focused mostly on negative emotions, which are known to affect surface temperatures. Positive and neutral affective states are in need of more research, as they have been studied less. Lateralization is also still a fairly new area of research. In this thesis I investigated if there would be detectable surface temperature patterns in riding horses at Cypis-talli, Espoo, that could be linked with mainly positive and neutral emotional states. I also explored the possibility of finding lateralization effects related to emotional states in horses. Additionally, I wanted to know if these changes in surface temperature would be situational or dependent on individual variation. We used naturally occurring situations in the horses’ lives to observe them in three situations: one where the horses got fed, one where they were taken outside to the paddocks after feeding, and one where the horses were momentarily separated from their paddocking buddies. During all situations the horses’ eyes and nasal region were measured with a thermal camera. Numerical data was collected from the images and analysed with linear mixed models and post-hoc pairwise comparisons. I found that there were significant changes in surface temperature in the eyes and nasal region of the horse that were likely related to changes in arousal. The surface temperature of the eyes and nasal region dropped when the horses got their feed, got taken outside to the paddocks and when they were separated and reunited with another familiar horse. Another finding was that there appeared to be a lateralization effect in the eyes and nasal region on the nasal cavities. There seemed to be a lot of individual variation in temperature throughout. An interesting finding was that the health condition of the horse significantly affected the temperature changes in many cases. My results suggest that surface temperature effects that have been previously seen in other species via IRT can also be detected in horses, and that the changes in temperature are most likely related to the emotional state and health status of the animal. Nasal temperature could be useful for measurement in future studies, but further research to validate its use in detection of emotional or health related states is required.
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(2023)Diets of wild owls have been studied by pellets, when the nutritional value of owl prey remains unclear. Fatty acids are an essential part of animal nutrition, acting as energy reserve, building blocks of membranes and precursors for signaling molecules. I studied whether Finnish owl species have species-specific characteristics in the fatty acid profiles of adipose tissue due to different diets and feeding habits. I also compared fatty acid profiles between wild and captive owls to elucidate if the diet of captive owls resembles the diet in the wild. Fatty acids from visceral adipose tissue and a liver were transesterified to fatty acid methyl esters, which were identified and quantified by gas-chromatographs linked to either a mass spectrometry or flame ionisation detector. The fatty acid compositions were compared with Principal Component Analysis and statistical significance of the separations between species, origins and tissues were studied by Soft Independent Modelling of Class Analogies. Differences in the relative concentrations of individual fatty acids and their structural category sums were evaluated by the Kruskal-Wallis test followed by the Wilcoxon rank-sum test. Compared to wild owls, captive owl (snowy owl Bubo scandiacus and Eurasian eagle-owl Bubo bubo) adipose tissues had lower relative concentrations of many long-chain polyunsaturated fatty acids (PUFAs), such as arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. The captive owls also had lower n-3 PUFA/n-6 PUFA ratio than the wild owls. I suggest that these differences arise from anthropogenic food given to the prey of the captive owls. In the future, the feeding and breeding of captive owls could be improved and potential health hazards prevented by giving the owls a diet rich in long-chain PUFAs, either by giving the prey more versatile diet or adding supplements to the owl’s diet. The adipose tissues of wild Eurasian eagle-owls contained higher total relative concentrations of monounsaturated fatty acids than the species belonging to the Strix genus. On the other hand, long-chain PUFAs were more prominent in the Strix owls. I suggest that these differences in the fatty acid composition are due to the disparities in feeding behaviour: the Eurasian eagle-owls eat carrions and large prey that cannot be swallowed whole, which may lead to consuming more the body outer parts of the prey. The fatty acid composition of the eagle-owls can also be affected by urban prey that have consumed anthropogenic food. In the future, the fatty acid composition of wild prey should be examined to be able to evaluate the prey composition of owls and its effect on the owl fatty acid profile with physiological consequences, the knowledge that could be used in the future decision-making that supports the conservation of owls.
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The effect of mowing height on CO2 fluxes and drivers of a clay soil under mixed forage cultivation (2023)Enhancement of soil carbon sink has large potential to mitigate climate change. Earlier studies have suggested that improved management practices could promote climate change mitigation and improve soil fertility. To find out if the carbon sink of a clay soil under improved grassland management in Southern Finland can be enhanced by increasing mowing height at harvest, an experiment was set up with two different mowing heights (6 and 15 cm). Net ecosystem carbon exchange, based on total ecosystem respiration and photosynthetic capacity were monitored with chamber methods during three growing seasons from 2019 to 2021. Also, plant biomass, leaf area index, soil temperature, soil pH, soil water retention capacity, and soil grain size distribution were studied at both mowing height treatments. In this study, negative value is the CO2 flux from the atmosphere to the ecosystem and positive value is the CO2 flux from the ecosystem to the atmosphere. Negative NEE means that the ecosystem gains C when the absolute value of GPP is greater than TER and vice versa. The higher mowing height increased CO2 uptake by plants and caused more negative NEE for the higher mowing height after the grass was harvested. These results indicate that higher mowing height might be better for mitigating climate change. However, mowing height did not have a significant effect on biomass, LAI, TER or soil properties in the experiment. Short lasting and non-existent differences between mowing heights are probably explained by more pronounced compensation growth reaction at the lower mowing height as growth conditions were otherwise similar except for mowing height treatment at both treatments. More frequent measurements, especially after the harvest, could better reveal the dynamics of grass height differences and its effects on GHGs. Better detection of the effect of mowing height on the carbon balance would require even more regular and continuous measurements after harvesting and fertilization in different soil types with experimental setups such as applied in this study.
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(2023)The aim of this study was to identify which bird impact types are considered significant in practice in Finnish environmental assessment reports regarding wind power. Increasing numbers of wind turbines can impact birds directly and indirectly, which could contribute to the loss of bird diversity. Amid climate change mitigation attempts, biodiversity loss should not be overlooked. Environmental impact assessment is an example of a policy tool for identifying and reducing the negative environmental effects of a project, including bird impacts. All wind power-related EIA reports with significant bird impacts were collected from the joint website of Finland’s environmental administration and analyzed with the help of qualitative content analysis. The 18 cases were divided according to the types of impacts found in the literature. Although all four impact types including collisions, displacement due to disturbance, barrier effect, and habitat change were considered significant in the EIAs, collisions were the most frequent. Very little comparable data about the significance of different impact types were found. However, collisions were the most researched impact type, which could have also contributed to the evaluation of its significance. The results corresponded to previous literature for the most part as Accipitriformes (diurnal birds of prey excluding falcons), according to several studies, are more vulnerable to the impacts of wind turbines. They were estimated to face significant impacts more often compared to other bird orders present in the materials. The reasonings between the cases were quite similar, despite the ambiguity of the significance assessment. In the cases where the reason for significance was stated, the level of protection of the species was the most common. The results also support the argument about how the impact type, the object of the impact, and the significance of an impact vary depending on the locations. The findings of this thesis suggest that scientific data is used at least partially in significance assessments. The results are useful in future research, developing EIA practices, and enhancing bird protection. Looking at significant impacts is relevant also in the future as the assessment of significance is not uncomplicated.
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(2023)Triple Negative Breast Cancer (TNBC) has the worst prognosis among all breast cancer subtypes. The lack of hormonal receptors and Her2 expression makes targeting with hormone-based treatments or anti-Her2 antibodies ineffective. Furthermore, TNBCs exhibit the highest expression of the oncogene MYC which negatively affects immune cell function. Natural Killer (NK) cells target transformed cells like cancer cells and have demonstrated promising clinical efficacy as treatments for hematological malignancies. However, NK cells have not yet been as successful in treating solid cancers, like breast cancer. The mechanism behind the lack of efficacy is not well understood, and therefore studies elucidating the mechanism are critical for improving the efficacy of NK cell therapies. In this study, we show that MYC-overexpression by itself does not affect the NK cell cytotoxicity of TNBC cell lines, however, if the NK cell response is initiated through antibody-dependent cellular cytotoxicity (ADCC) then MYC expression inhibits NK cell-mediated killing. Many TNBC cell lines are resistant to classical NK cell cytotoxicity, which we show can be overcome with ADCC-inducing antibodies. MYC overexpression has an inhibitory effect in two out of three NK cell donors, when overexpressed in the presence of ADCC-enabling antibodies. This indicates some degree of heterogeneity in MYC regulation of ADCC-dependent cytotoxicity. Our results also demonstrate that when MYC is overexpressed in TNBC cell lines, NK cell activating ligands are downregulated on the tumor cell surface, which could explain the MYC-mediated inhibition of NK cells. This is consistent with other studies where MYC overexpression downregulates NK cell activating ligands in cancer cell lines and inhibits NK cell killing. Altogether, we demonstrate a functional role of MYC in the inhibition of ADCC-dependent NK cell cytotoxicity in TNBC. These findings could explain the inhibitory function of tumor cells on NK cells and provide the rationale for exploring MYC-overexpression as a biomarker for predicting a response of breast cancer patients to NK cell-based immunotherapies.
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(2023)Lethal congenital contracture syndrome 1 (LCCS1) is a severe developmental disorder that is part of the Finnish disease heritage. The affected foetuses die in utero and show a lack of motor neurons accompanied by severe atrophy of the ventral spinal cord and muscles and severe contracture of joints, which result in a lack of involuntary movements. Other associated symptoms include hydrops, micrognatia (small jaw), pulmonary hypodysplasia and small size. The syndrome leads to prenatal death before 32nd gestational week, but the cause remains elusive. LCCS1 is caused by a homozygous mutation, FINmajor, in GLE1 RNA export mediator (GLE1) -gene. The mutation is a c.432- 10A > G substitution at the border of intron three and exon four, resulting in a new splice acceptor site 10 nucleotides upstream of the intron-exon junction. This results in aberrant splicing and nine extra nucleotides in the mRNA, corresponding to three extra amino acids in the GLE1 protein of the affected individuals. GLE1 is an important player in RNA biology in cells. In humans it has two isoforms, GLE1A and GLE1B, that have distinct roles. While GLE1A plays a role in cells’ stress response by mediating the formation and disassembly of stress granules in the cytoplasm, GLE1B is found at the nuclear envelope where it mediates mRNA transport from the nucleus to the cytoplasm. Earlier studies using HeLa cells and zebrafish have demonstrated that FINmajor in GLE1 knock-down background disrupts the mRNA export from nucleus to cytoplasm and leads to apoptosis in neural precursors and abnormal arborization of motor neurons, thus mimicking some of the phenotypic features observed in human patients. Kuure group has generated a mouse model with endogenous FINmajor, but it fails to morphologically phenocopy the human disorder (unpublished data). Importantly, human-origin non-cancerous models with endogenous FINmajor mutation have not yet been used in the studies of GLE1 and LCCS1. My aim in the thesis was to create a human embryonic stem (hES) cell line carrying homozygous FINmajor mutation in its genome. A relatively new tool, CRISPR/CAS -system allows for precise genetic engineering in a variety of model organisms. By optimizing the system to efficiently edit the GLE1 gene, I was able to introduce FINmajor mutation in hES cells, creating a new model system to study this disorder. While previous models had relied on temporary silencing of the gene with morpholinos or siRNAs, the hES cell line with GLE1 FINmajor mutation will for the first time give insights on how the mutation affects cellular functions, mRNA biology and cell differentiation in LCCS1. This way the hES cell line I have generated will yield new information on the development, progression and manifestation of the syndrome to better understand its mechanisms.
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