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Cornea is transparent layer of cells lying in front of lens. The corneal epithelium, a squamous epithelium, covers the ocular surface and ensures proper vision by preserving the integrity of the eye. Corneal epithelium is renewed continuously throughout life from a pool of stem cells (SC). There are still conflicting theories about the localization of stem cells required for the growth, renewal and maintenance of the corneal epithelium. Previous studies demonstrated that the limbus, located in the periphery of the cornea, serves as the stem cell niche (SCN) in adults. However, contrasting evidence from clonal analysis proposes that, in early postnatal life, renewal is fuelled by SCs located in the basal layer of the central cornea. There are alternate patterns of renewal in young and adult mouse cornea and that there is an important, transitional time frame called cornea maturation, when the adult patterns of gene expression, cell dynamics and tissue renewal are established. In the cornea, solid SC markers are still missing, yet studies on human limbal cells have suggested Bmi1 and C/EBPδ as limbal SC markers. There are, indeed, long-lived SCs in the central cornea and that the gene Bmi1 plays a role in these central corneal SCs. However, the physiological importance of these Bmi1+ cells remains obscure. The main aim of this project is to understand the fate and dynamics of these Bmi1+ cells and study the chronology of maturation of the cornea. In this study, I have also tried to correlate the growth of eye size with proliferation of corneal epithelial cells This study was conducted using few different kinds of transgenic mice (Mus musculus). To study the fate of Bmi1+ cells, two different mouse lines were crossed: Bmi1-CreER and ROSA26-LacZ. Mice carrying both alleles were used for lineage tracing experiments. Moreover, Hematoxylin-eosin staining was used to follow the eye morphology. Immunohistochemistry was performed to follow the chronology of maturation of the cornea, proliferation of corneal epithelial cells and the location of Bmi1+ cells in corneal epithelium. From this study, we can propose that cornea maturation is completed by the time of eyelid opening, which take place two weeks after birth. Krt19 is perfect for studying the chronology of the corneal epithelium, immunostaining of Krt19 separates the territory of limbus from central cornea enabling to distinguish limbus distinctly. Proliferating cells reside in basal layer of cornea. Bmi1+ cells found throughout the basal layer of the cornea that locally renews the corneal epithelium concluding Bmi1+ cells as the progenitor cells.

This master’s thesis addresses the role of intermediary organizations in sustainability transitions, specifically in the field of energy. The thesis discusses how intermediary organizations can diffuse and support the development of novel sustainable socio-technical niche-innovations through experiments. Theoretically, this thesis draws mostly upon the sustainability transition literature, particularly strategic niche management theory. Empirically, this thesis focuses on a case study of joint procurement of solar power plants that was implemented as a part of “New and innovative low-carbon business generates competitive advantage for companies and municipalities” (Välke) project in South-western Päijänne during 2016. Välke is a sub-project of Carbon-neutral municipalities (HINKU) and therefore the case study of this thesis links to other similar experiments in the HINKU network. The material of the thesis was collected through 9 semi-structured interviews with different stakeholders involved in the experiment and by using pre-existing secondary material. The material was analysed by qualitative content analysis using an analytical framework adopted from a previous study. The findings show that intermediaries support niche development by aggregating, circulating and applying lessons learned between and within joint procurement experiments. This was done by producing and disseminating documents, but more importantly through personal contact between intermediaries. The network of intermediaries showed hierarchical features as the coordinator of HINKU, the Finnish Environment Institute (SYKE), maintained the repositories of the learned lessons and also formed a link between municipal intermediaries involved with the experiments. Also, during the experiments the more experienced higher profile intermediaries – mostly SYKE – provided assistance to lower profile municipal intermediaries. This support included providing knowledge, but also raising the confidence of lower profile intermediaries. Following, the lower profile intermediaries provided similar assistance to the participants of the experiments. However, the intermediary roles were not stable as lower level intermediaries were adopting some of the roles of the higher profile intermediaries after gaining experience during the experimentation. In order to support the Finnish solar niche, the intermediaries went beyond mere aggregating, circulating and applying lessons between and within experiments. They were actively initiating new experiments in adjusted formsin new geographical locations and advocating the niche. This was partially linked to the strategic nature of the intermediaries, as they were established to catalyse activities that would lead to mitigation of greenhouse gas emissions. However, this active support for a particular socio-technical innovation contradicted the pursuit of intermediaries to be viewed as neutral and credible actors. Partially as a consequence – but also because of the phase of solar niche development in Finland and lack of resource and interest – SYKE chose to withdraw from future joint procurements of solar power plants for private actors. However, SYKE was planning to utilize the governance innovation of joint procurements in order to support other niche-innovations with sustainability gains. The findings show that intermediaries can accelerate energy transitions, at least on a regional scale. They emphasize the importance of cooperation and personal contact between intermediaries and the ability of intermediaries to utilize governance innovations. Also, the findings support stronger inclusion of intermediaries in governance frameworks to hasten energy transition and achieve wider sustainability goals. However, the thesis shows that particularly public intermediary organizations have to work under unclear mandates.

Three-dimensional (3D) cellular cultures have been shown to represent tissue formations and functions more accurately than two-dimensional (2D) cultures and have been successfully utilized more accurately in model organisms, e.g., to understand cellular modular functions. However, the applications in non-model organisms are limited, and to our knowledge have not been implemented in ectotherms. At an ecological scale, the technique can enhance our understanding by providing insights on cellular and tissue level molecular mechanisms. A potential implementation of this method in Atlantic salmon is to elucidate the molecular function of the vestigial-like 3 (vgll3) gene, which plays a central role in salmonid maturity, potentially by regulating energy allocation via regulating adipogenesis. In this thesis, a proof of principle study was implemented, where the feasibility of obtaining and maintaining a suspension 3D adipose tissue culture in Atlantic salmon (Salmo salar) was assessed. The harvested visceral white adipose tissue from around the intestinal tissue of mature Atlantic salmon (salmon past smolt stage) was first separated into stromal vascular fraction (SVFs) and mature adipose fraction (MAFs). SVFs contain preadipocytes (precursors of adipocyte cells) in addition to a variety of other cell types. MAFs are mature adipocytes. Both MAFs and SVFs were successfully maintained in-vitro for over four weeks. SVFs were then successfully differentiated into mature adipocytes, demonstrating the feasibility of studying adipogenesis in Atlantic salmon. Proof of this methodology and its further implications may help us to understand the cellular functions of vgll3 and may subsequently help to better understand its causal relation to the maturation process in Atlantic salmon.

Human induced pluripotent stem cells (hiPSCs) are derived from adult differentiated somatic cells and reprogrammed to an embryonic-like state. Pluripotent stem cells can be differentiated into almost any somatic cell type by using directed differentiation methods, but the differentiation efficiency often varies depending on the cell type. hiPSCs and cells differentiated from them can be used as a disease model carrying the patient’s phenotype and genotype. Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease where both upper and lower motor neurons degenerate, leading to paralysis. There is no curative treatment for ALS, and it leads to the death of the patient in 3 to 5 years on average from the first symptoms. The most common genetic cause of familial ALS is a hexanucleotide repeat expansion in C9orf72-gene. ALS pathology is strongly linked to endoplasmic reticulum (ER) stress, which affects cell homeostasis and proteostasis, and leads to apoptosis when prolonged. The primary aim of this research is to characterize the differentiation of four hiPSCs lines towards lower motor neurons and to study the neuroprotective effects of cerebral dopamine neurotrophic factor (CDNF) and CDNF-derived peptide on ER stress and cell viability. This experiment used two control cell lines from two healthy donors and two patient cell lines from two different ALS patients carrying the C9orf72-mutation. To evaluate the efficiency of the differentiation towards motor neurons, molecular markers for pluripotent and neural progenitor cells as well as for maturated motor neurons were analyzed. Relative gene expression levels were measured from weekly time points with qPCR. Immunocytochemical (ICC) antibody staining was performed during differentiation. Endogenic CDNF levels were analyzed from differentiating cells at weekly time points and the effect of CDNF on Thapsigargin (TG) -induced ER stress in motor neurons was analyzed. In addition, cell viability was analyzed in TG-CDNF treatment. All pluripotent and progenitor markers were downregulated in differentiated cells, and the expression of the mature motor neuron markers was upregulated. Mature motor neuron markers were also expressed at the protein level. The endogenous CDNF levels were highest at the progenitor cell stage. The ER stress response was upregulated in TG-treated cells, and there were no differences between treatments against ER stress. Furthermore, TG and growth factor treatments differentially affected the viability of the control and patient cell lines. Treatment decreased viability in control cell lines and increased viability in patient cell lines. Pluripotent stem cells were successfully differentiated toward motor neurons. The differentiation was performed twice, and the results were similar on both individual biological repeats. Analysis of endogenous CDNF expression levels was performed for the first time on hiPSCs lines. In this study, CDNF or its derivate didn’t reduce ER stress but it influenced cell viability, especially in patient cell lines with growth factor treatment. In the future, TG-treatment could be optimized regarding timing and growth factor treatment, or the toxin could be changed to another ER-stress inducing toxin. In addition, the C9orf72 pathology should be identified in order to use differentiated motor neurons as a pre-clinical disease model.

Breeding-dispersal and philopatry are important life-history traits when it comes to the ecology of animals. A number of factors such as sex, age, habitat stability, population density, predation and various environmental factors influence the movement patterns of species. Philopatry, in general, can be used by organisms as a predator avoidance strategy and to improve feeding efficiency. Dispersal on the other hand has been shown to help avoid inbreeding and competition within groups or between kin. Among the different types of dispersal and philopatry, breeding dispersal and site fidelity to breeding sites have been studied in many vertebrates. Many birds and some ungulate species have been the focus of these studies and have shown that breeding success influences site fidelity. Among ungulates, the reindeer genus (Rangifer tarandus spp.) however, has received little attention for this topic. A species of special conservational value is the wild forest reindeer (Rangifer tarandus fennicus), which is a rare, and near-threatened subspecies of reindeer living in Finland. Knowledge of factors influencing the dispersal and site fidelity for this species is lacking but has important implications for the conservation and management of this and other vulnerable species. In my thesis I investigated the philopatry of wild forest reindeer females from eastern Finland and tested if the calving site fidelity was influenced by breeding success, predator pressure and the female’s age. Given the high densities of predators in the study area (Kainuu) and thus high predator pressure on reindeer, I expected (i) the philopatry of the wild forest reindeer female’s to be stronger in areas with higher predator pressure but (ii) higher dispersal movement when wild forest reindeer females had no breeding success the previous year. Additionally, I expected (iii) the dispersal distances of wild forest reindeer females to be negatively correlated with their age. For this study I used long-term GPS monitoring data of 53 collared wild forest reindeer females, which were followed for varying periods (2-6 years) between 2010-2021 from Eastern Finland. I found that the inter-year distances between calving sites per female had a median distance of 2.84 km, confirming that female wild forest reindeer show philopatry to calving sites, as do other reindeer subspecies. Even though the movement ranged from 4.8 m to 36.99 km, showing substantially longer dispersal for some individuals. The model outcomes indicate some association between predation pressure and site fidelity, and reduced philopatry following calf mortality, although none of these associations were significant. The age of the mother did also not show any significant influence on a female’s site fidelity. Nonetheless, these results would suggest that a mother's choice to leave or return to the same calving site might be influenced by the previous year's calf mortality but more complex variables like anthropogenic disturbances, environmental factors, as well as intrinsic factors and the physical condition of the mother most likely also play a role in this.

Carbon capture and storage may become an inevitable means in mitigating climate change. However, it is a new technology involving a great deal of uncertainties. It is of utmost importance to understand on one hand, the risks caused by the technology and on the other, what is holding it back. This way unforeseen setbacks and environmental or other damage could be avoided. This thesis is a part of a wider research project on the risk governance of carbon dioxide capture and storage (RICCS). The present study gives additional insights to CCS risk analysis by diving into the stories that the media tells about the risks. I analyze the media coverage on the risks of CCS in the most wide spread newspapers of Norway and Finland with the aim of identifying what kind of risk framings are portrayed by the media; how strong is the presence of uncertainties and what kind of uncertainties are brought up. The media is seen as a mirror of public perception, but also one of the players influencing it. The possible effects that the analyzed articles could have on public perception of risks are discussed. The theoretical framework consists of theories of systemic risks, narrative policy analysis and framing of environmental risks in the media. I describe the nature of systemic risks. Then I move on to framing, more specifically how environmental risks are framed in the media and how it can effect public perception. After this I explain how narrative analysis can be used as a tool for identifying framings. Then I describe Klinke and Renn's Prometheus theory that I will use for analyzing the level of uncertainty in the framing of the articles and for discussing the implications of my findings. The results show that the risks caused by CCS are mainly the lock-in in fossil fuels, it's possible negative effect on developing renewable energy and environmental and health risks in general. The risks towards successful CCS seem to be mainly connected to funding, which connects to emissions' prices, the climate agreement and viability of investments. The differences between the two countries are quite related to the situation in which each country is in terms of CCS development. Norway is very active and pushing CCS forward. Consequently, the Norwegian articles are generally not very critical of the technology itself, but discuss what is holding it back. Generally, the Finnish articles bring out more aspects on the issue, both positive and negative, leaving quite an ambiguous image to the reader. The implications of my findings for future policy practices are quite extensive and therefore not very useful, since most policy recommendations seem more or less relevant. What is interesting though, is that based on my findings I could identify the turning points in which public perception is most relevant. These are: What kind of energy production is supported? Is CCS an acceptable mitigation means? Is the risk of leakage taken as severe? These issues represent turning points for the future of CCS technology and deliberative processes can be crucial when discussing them.

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.

Physical fitness has declined during the last decades in adolescents. Furthermore, several studies have found a positive association between physical fitness and brain volume in adolescents, which is noteworthy since the adolescent brain undergoes substantial changes during growth and maturation. However, despite the importance of the cerebellum on adolescents' cognition and coordination, there remains a paucity of evidence on the associations between physical fitness and cerebellum characteristics. Thus, a cross-sectional approach was used to explore the relationship of cardiorespiratory fitness (CRF), power, speed-agility, coordination and overall neuromuscular performance index (NPI) with total gray matter (GM) volume of the cerebellum as well as lobules VI & VIIb, and crus I volume in 40 (22 girls; 18 boys) adolescents. Peak oxygen uptake (V̇O2peak) was measured by the maximal ramp test on a cycle ergometer, lower limb power was determined with standing long jump (SLJ), speed-agility was assessed with the 10 x 5-m shuttle-run test, upper limb coordination was determined with the Box and Block Test (BBT) and NPI was calculated as the sum of SLJ, BBT and shuttle-run z-values. Lean mass (LM) and body fat percentage (BF%) were measured using a bioelectrical impedance analysis. Cerebellum GM volume, lobules VI & VIIb, and crus I volumes were measured by magnetic resonance imaging (MRI). Results demonstrated that V̇O2peak/LM was negatively associated (β = -.045 P= .014) with cerebellum GM volume. No statistically significant associations were found between SLJ, shuttle-run, BBT scores or NPI and cerebellum characteristics in all participants. However, a poorer shuttle-run time was associated (β = -.363 P = .024) with smaller crus I volume in girls and V̇O2peak/LM was negatively associated (β = -.501 P = .031) with lobule VIIb volume in boys. These findings suggest that, in general, CRF and speed agility are associated with cerebellum characteristics in adolescents and there may be sex differences. The results extend our knowledge of the associations between physical fitness and brain volume, but more studies should be conducted to understand the relationship further.

Lymphangiogenesis is the process that leads to the formation of lymphatic vessels from pre-existing vessels. Vascular endothelial growth factor C (VEGF-C), the ma- jor lymphangiogenic growth factor, is produced as an inactive precursor and needs to be proteolytically processed into a mature form in order to activate its receptors VEGFR-3 and VEGFR-2. A deficiency of VEGF-C during embryonic lymphangiogenesis results in embryonic lethality due to the lack of lymphatic vasculature. Hennekam lymphangiectasia-lymphedema syndrome (OMIM 235510) is in a subset of patients associated with mutations in the collagen- and calcium-binding EGF domains 1 (CCBE1 ) gene. CCBE1 and VEGF-C act at the same stage during embryonic lymphangiogenesis and their deficiency results in similar lymphatic defects. The mechanism behind the lymphatic phenotype caused by CCBE1 mutations is un- known. The aim of this study was to investigate the potential link between VEGF-C and CCBE1 that could contribute to the lymphatic phenotype. In this study, 293T cells were used to observe the effect of CCBE1 on VEGF-C pro- cessing. The co-transfection of constructs coding for CCBE1 and VEGF-C showed processing of the inactive pro-VEGF-C into the active, mature form. However, this processing was efficient only in 293T cells. When CCBE1 from 293T supernatant was purified, A disintegrin and metalloproteinase with thrombospondin type 1 motif 3 (ADAMTS3) co-purified with CCBE1. The levels of pro-VEGF-C and active VEGF-C were monitored by immunoblotting or immunoprecipitating metabolically labeled supernatant with specific antibodies or receptors followed by autoradiography. The activity of the processed VEGF-C was verified by proliferation of Ba/F3 cells stably expressing VEGFR-3/EpoR or VEGFR-2/EpoR chimeras. Furthermore, a VEGFR-3 phosphorylation assay was performed in PAE (Porcine Aortic Endotheial) cells to study details of the CCBE1-mediated regulation of VEGF-C. We found that CCBE1 increases the proteolytic processing of pro-VEGF-C, thereby resulting in increased activity of VEGF-C. CCBE1 itself has no effect on VEGF-C activity but regulates VEGF-C by modulating the activity of the ADAMTS3 protease. We also found that both pro- and mature- VEGF-C can bind to VEGFR-3 but only mature form is able to induce VEGFR-3-mediated signaling. In addition to cleaving VEGF-C, ADAMTS3 was found to directly or indirectly mediate CCBE1 cleavage. The N-terminal amino acid sequence of the ADAMTS3-processed VEGF-C confirmed that ADAMTS3 is the protease responsible for the activation of VEGF-C by 293 cells. Hence, we have identified a mechanism that regulates VEGF-C activity. This mechanism suggests the possible use of CCBE1 as a therapeutic means to treat diseases that involve the lymphatic system.

Forest certification has been used as a tool to promote forestry responsibility towards sustainable forest management. Forest Stewardship Council (FSC) is one of the certification systems that is well recognised in Europe. Nevertheless, compared to other European countries, the number of FSC chain of custody (CoC) certifications in Finland is relatively low. Semi-structured interviews were conducted with six FSC CoC certified companies to explore their experiences towards implementing and maintaining the system in their companies. The sample group was comprised of wood and paper product industries in manufacturing and trading sectors. Thematic analysis of the interviews revealed the challenges companies encountered. The results indicated that there were eight types of challenges, including three internal and five external ones, hindering the development of FSC CoC certification in Finland. Internal challenges included competence, financial resources, and a lack of motivation to change. External challenges included insufficient marketing and demand, uncertain cost benefit, keen competitor programmes, limited supply, and long trademark approval time. Meanwhile, the relevant solutions these companies adopted to deal with the challenges were discussed. Since external challenges out-numbered internal ones, it seemed that certified companies are not able to tackle the existing challenges alone. Joint-effort among other actors in the forestry sector, for instance, the national authority, FSC national office, certification bodies are essential to influence the rate of certification uptake. Furthermore, participants discussed about the future development of FSC CoC certification system in Finland. Interviewees believed that the enactment of the EU Timber Regulation (EUTR) and the introduction of forest certification into national public procurement policy could positively impact the development of the system. The results of this study could be used as a reference for potential certificate users to prepare themselves for implementing FSC CoC certification system. In addition, the study could shed a light on the development of FSC in Finland in the future.