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(2024)Background: The infant gut microbiome undergoes major temporal changes in the first year of life, crucial for supporting normal development and long-term health. The immense diversity of fiber structures in breast milk and later in solid foods pose unique selection pressures on the gut microbiome maturation by providing novel substrates for the microbiota. However, the longitudinal impact of complementary food-derived fibers on the taxonomic and functional maturation of the gut microbiome during the gradual transition from breast milk to solid foods is not well understood. Objectives: My objective was to examine how breast milk, its fiber and complementary food fibers in the broader context of overall infant diet may affect the gut microbiome bacterial species composition and support age-appropriate gut bacterial maturation trajectories during first year of life. Methods: Longitudinal and cross-sectional development of 68 infant gut microbiomes and 33 metabolomes were examined with linear mixed models to determine the impact of infant nutrition on gut microbiome taxa and functional development. Nutrition assessments were based on detailed quantitative weighted 3-day food records (months 3,6,9,12) and the intakes of total dietary fiber with its food sources and fiber fractions relied on current internationally approved CODEX-compliant values. Questionnaires were utilized to monitor when various complementary foods were introduced, enabling more comprehensive nutritional analyses. Bacterial species identification was based on MetaPhlAn2 quantification of bacterial species from metagenomic data and metabolomic profiles were generated using four liquid chromatography-mass spectrometry (LC-MS) methods. Results: My examinations place the previously described sequential trajectories in infant gut microbiome maturation into detailed fiber-dependent nutritional context relying on metagenomic species identification. I discovered 176 complementary food derived fiber-bacterial species associations. The majority of the associations (147, 84%) were positive whereas breastfeeding and related variables tended to be inversely associated with the same species, showing strongest inverse correlations to later trajectory species indicative of slower maturation. Both bacterial species and metabolomic profiles displayed pronounced longitudinal shifts in response to solid food fibers. Each introduction of novel dietary source of fiber associated to diversification of the microbiome revealing fiber-species specific temporal patterns. Conclusions: The longitudinal analyses highlight that sufficient fiber intake from appropriate sources during the weaning period likely function to build capacity for the species permanence in the more diverse and stable mature gut microbiome composition and function reached in later childhood.
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(2024)Peatlands are a significant carbon and nitrogen reservoirs, making them potential sources of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions. Variations in water table level change the oxygen content of peat, affecting the oxidation-reduction or redox state of the peat, which is known to influence the biochemical processes and thus greenhouse gas (GHG) emissions. The aim of this study was to assess the effect of controlled anoxic redox conditions and inorganic electron acceptors (TEAs) on redox potential (Eh), and N2O, CH4, and CO2 emissions. In this study during an anaerobic incubation experiment, the rates of formation of these GHGs and Eh values as a function of time were measured from drained (D) and undrained (UD) peat of three nutrient levels: mesotrophic (ME), oligotrophic (OL), and ombrotrophic (OM). Redox conditions were controlled to three levels by nitrate (NO3-), ferric iron (Fe3+), and sulphate (SO42-). In addition, measurements were performed on untreated (Ctrl) peat. The peat was in an anoxic state throughout the incubation (Eh < 300 mV) and the values were in the order of TEA reduction, even though they were mainly in the iron and manganese reduction zones, probably due to the naturally high iron content of the peat. As expected, N2O formation was highest in flasks with added NO3-, and N2O formation was weak and ceased without addition. CH4 formation was reduced in flasks with added NO3- or SO42-, and SO42- addition also inhibited CO2 formation on which NO3- addition had no effect. In contrast, the addition of Fe3+ increased both CO2 and CH4 formation compared to Ctrl treatment, and it is possible that methanogens were involved in the reduction of Fe3+. In Ctrl flask, the redox state did not decrease to the lowest level compared to the other treatments as expected, but the Ctrl treated UD ME peat had the highest CH4 formation at the end of incubation. For all treatments, GHG emissions were higher from nutrient-rich peat in the descending order ME > OL > OM. In general, UD peat also had higher gas formation than D peat. All GHGs were formed the most while Eh values were around 0 mV and the value was especially high for CH4 formation, probably due to the linkage between methanogens and iron. The poor ability of the Pt electrode to detect NO3- or oxygen was the most likely reason for the variable and low Eh values of the flasks with NO3- addition. For the same reason, oxygen leakage of the anaerobic chamber was most likely responsible for the varying Eh values measured from Ctrl treated OM peat. This study suggests that Eh measurement is a useful predictor of the redox state and reactions, but it must be considered together with other measurements and analyses such as microbial analysis, nutrient analysis, and GHG measurements to predict redox processes and GHG emissions in anaerobic peatland. In particular, the role of iron on CH4 emissions requires further research.
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(2024)Itämeri ja Suomenlahti ovat voimakkaan ihmisvaikutuksen alaisena, mikä on aiheuttanut suuria muutoksia monissa kalapopulaatioissa. Tästä huolimatta tieto rantavyöhykkeen kalaston tilasta näissä olosuhteissa on vähäistä ja paikoittaista: tietoa niiden pitkän ajan kehityksestä 2000-luvun Itämeressä ei ole. Tutkin touko-syyskuussa 2023 rantavyöhykkeen kalastoa poikasnuottaamalla Hangon Tvärminnessä, läntisellä Suomenlahdella. Selvitin kalojen runsauden alueella laskemalla sekä kalojen määrän pyyntiponnistusta kohti että kalaston yksilötiheyden. Kartoitin kalaston lajikoostumuksen laskemalla lajien suhteelliset runsaudet, sekä laskemalla ajallisia ja alueellisia diversiteetti-indeksejä. Vuodenaikaisvaihtelua selvitin vertailemalla kuukausittaisia saaliita, sekä arvioimalla poikasten määrän ajallista vaihtelua. Vertailemalla tuloksiani tietoihin vuodelta 1992 tutkin kalastossa tapahtuneita pitkän ajan muutoksia. Kalojen runsaus romahti yli 90 % vuodesta 1992 vuoteen 2023. Yksilömäärän lasku koski lähes kaikkia lajeja, ollen rajoittumatta sellaisiin, jotka suosivat tiettyjä ympäristön olosuhteita. Vuoden 2023 saaliissa oli kolme uutta lajia, kun taas kymmentä vuonna 1992 esiintynyttä taksonia ei havaittu. Runsaimmat lajit 2023 olivat kolmipiikki (Gasterosteus aculeatus L., 1758), salakka (Alburnus alburnus L., 1758), liejutokko (Pomatoschistus microps Krøyer, 1838) ja hietatokko (Pomatoschistus minutus Pallas, 1770), jotka muodostivat yli 90 % saaliista. Silakka (Clupea harengus membras L., 1761), kilohaili (Sprattus sprattus L., 1758) ja ahven (Perca fluviatilis L., 1758) olivat erittäin runsaita 1992 mutta erittäin harvassa 2023, kun salakan määrä taas kasvoi yli kaksikymmenkertaisesti. Poikasten ilmaantuminen runsaissa määrin tapahtui kuukautta myöhemmin vuonna 2023, todennäköisesti johtuen kylmemmistä alkukesän lämpötiloista. Kalamäärän romahdus on todennäköisesti seurausta sekä vuosittaisesta poikasmäärän vaihtelusta että kalojen vähenemisestä pitkällä aikavälillä. Silakan, kilohailin ja ahvenen vähäiset määrät johtuvat todennäköisesti poikasmäärän vuosittaisvaihtelusta, joskin tämän varmistaminen vaatii vuosittaisia mittauksia. Salakan määrän runsas kasvu viittaa rehevöitymisen ja vesien lämpenemisen vaikutukseen. Tulokseni korostavat tähän mennessä huonosti tunnettujen pitkän ajan muutosten laajuutta Itämeren rantavyöhykkeen kalastossa.
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(2024)Nuclei isolation is a method used e.g. as a part of chromatin structure research. DNA structure can be examined in its 3D form from isolated nuclei because DNA is still wrapped around the histone proteins. Examining the chromatin structure can offer information e.g. about gene expression and how it is regulated. Isolating nuclei from plant cells demand more optimization compared to animal cells because of the cell wall, chloroplasts and secondary metabolites. The presence of organellar DNA can hamper the later DNA analysis. Secondary metabolites can hinder the actual isolation process. Finding the suitable isolation protocol for species of interest may need careful optimization of different aspects. Different species can differ from each other based on the structural and biochemical characteristics and because of this the same protocol may not ensure as good results for them. Different tissue types of the same species may have also differences in their biochemical and structural characteristics. In this thesis work, three different isolation protocols were used for three plant species; Pinus sylvestris, Betula pendula and Arabidopsis thaliana. The purpose of the work was to compare the results from each nuclei isolation protocol. Optimization of isolation protocol for P. sylvestris and B. pendula would help the isolation process for later research. Thesis work was done to get guidance for this optimization. Samples handled with different protocols were different from each other based on the sample concentration (particles/mL) and the average size of isolated particles. Chloroplast contamination was tested with chloroplast specific primers with PCR. None of the samples were free from chloroplasts.
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Identifying the disease-causing variant in a large family with a late-onset dominant distal myopathy (2024)Distal myopathies are a group of rare progressive genetic muscle disorders that are extremely varied both genetically and clinically. Typical symptoms include weakness and atrophy limited to the skeletal muscles of distal extremities in hands and legs. The age of onset ranges from early childhood to late adulthood depending on the disease. Currently around 30 genes have been associated with distal myopathies, most of them causing a dominant disease. The objective of the thesis was to identify the disease-causing variant in a family affected by autosomal dominant distal myopathy with early adulthood onset. Affected family members expressed weakness and atrophy in muscles of both hands and legs. To narrow down the chromosomal location of the disease-causing variant, linkage analysis was conducted with genome-wide single nucleotide polymorphism data of family members. Because of the progressive nature of the disease and uncertain disease status of one family member, linkage analysis had to be repeated a few different times with different settings. Both disease statuses and pedigree size were altered to account for the possibility of presymptomatic carriers or incomplete penetrance. Analyses with different parameters led to discovery of multiple possible co-segregating regions. Rare co-segregating small-scale and structural variants as well as repeat expansions in these regions were examined from next-generation sequencing data with multiple bioinformatic detection tools. The segregation of possible candidate variants was validated with Sanger sequencing and PCR. Ultimately, no likely rare co-segregating variant of any type of genetic variation with a likelihood to cause a disease such as distal myopathy was identified by any detection method used. Lack of potential disease-causing variant could be due to incomplete penetrance of the variant or if it was in non-coding regions, such as a deep intronic splicing variant in a gene currently not known to be connected to muscles.
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(2024)Background and objectives: Since early adolescence, the bedtimes and wake-up times begin to delay gradually until the early adulthood. This so-called shift to eveningness reaches its maximum at around the age of 20, and it usually occurs earlier in girls than boys. Eveningness has been previously associated with depression, anxiety, sleep problems, somatic symptoms, and other health-related issues in adolescents and adults. The aim of this study is to examine the associations between adolescents’ chronotype and their physical and mental well-being. Methods: This study examined how the self-reported chronotype was associated with self-reported problems related to adolescents’ physical and mental well-being. The chronotypes were divided into 5 types: Definitive Morning-types, Moderate Morning-types, Intermediate-types, Moderate Evening-types, and Definitive Evening-types. The participants were 7th, 8th and 9th graders, and the sample consisted of 6522 students from 83 schools in Finland. Some of the data was gathered at three time points, some at two time points, and some at one time point during the academic year. The associations between chronotype and well-being variables were studied cross-sectionally and some of them also longitudinally. Results: The main findings were that eveningness was associated with difficulty concentrating in lessons, susceptibility to give up easily on difficult tasks, school burnout symptoms, feelings of nervousness and anxiety, excessive worrying, difficulty relaxing, irritability, restlessness, difficulty falling asleep, waking up at night, daytime tiredness, and low mood as compared to morningness. Eveningness was also associated with neck and shoulder pain, lower back pain, and headache, as well as pain in the head and lower back due to the use of digital devices. Eveningness was associated with decreased concentration in lessons and increased susceptibility to give up on difficult tasks across time. On the other hand, feeling lonely and not being accepted as part of the group were associated with morningness. Conclusions: In conclusion, the physical and mental health problems were emphasized among Evening-type adolescents, as compared to Morning-type adolescents. Since adolescents shift toward eveningness, the need for thorough management of sleep and circadian problems should be highlighted, in order to intervene and improve the mental and physical well-being of adolescents both at school and at home.
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(2024)Vaatetusala on tärkeä hyvinvointia tuottava teollisuudenala. Se on myös hyvin kuormittava ympäristölle. Kiihtyvä kulutus ja vaaralliset työolot ovat osa alan haastetta. Kiertotaloudesta on kaavailtu näihin ongelmiin ratkaisua. Sen tavoitteena on korvata vaatteiden lineaarinen tuotantomalli luonnon kiertokulkuun perustuvalla mallilla sekä mahdollistaa talouskasvun ja luonnonvarojen kulutuksen irtikytkentä lisäämällä samalla hyvinvointia. Kiertotalousprojektia leimaavat heikkoa kestävyyttä peilaavat teknis-taloudelliset ratkaisut eivät yksinään mahdollista riittävää muutosta vaan kulutuskulttuurin haastaminen on välttämätöntä. Tässä tutkielmassa on selvitetty käytäntöteorian keinoin, millaisia kiertotalouteen liittyviä käytäntöjä suomalaisissa pienissä vastuullisissa vaatetusalan yrityksissä toteutetaan. Aineistosta havaittiin kahdeksan eri käytäntöä, jotka liittyivät liiketoiminnan ja tuotannon eri osiin sekä erilaisiin kiertotalouspalveluihin. Kertotalous näyttäytyi vaatetusalalla yritysten näkökulmasta sekä inspiroivana mahdollisuutena että vakavana uhkana yritystoiminnalle. Talouskasvun ja kulutuksen irtikytkennän dilemma oli osoittautunut haastavaksi ratkaista, etenkin innovatiivisen liiketoimintaosaamisen ollessa toistaiseksi yrityksissä puutteellista. Tutkimuskirjallisuuden havaintoja mukaillen kiertotalousliiketoiminta on hyvin haastavaa ja edellyttää vaatetusalalla vallitsevien normien kyseenalaistamista, joka on pienille yrityksille lähes mahdotonta yksin. Muutos voisi mahdollistua, mikäli kuluttajat nousisivat yritysten aktiivisiksi kanssatoimijoiksi, julkisen sektorin tukiessa toimintaa. Toistaiseksi vaatetusala kuitenkin noudattaa perinteistä, lineaarista tuotantomallia ja kiertotalousprojekti sekä sen tavoittelema laajamittainen yhteiskunnallinen muutos on jäämässä utopistiseksi visioksi.
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(2024)Alzheimer's disease (AD) is a degenerative brain disorder that exhibits deterioration as one gets older. Although much remains to be learned about the pathophysiology of AD, there is strong evidence links amyloid beta (Aβ) plaques, which are responsible for cognitive impairment, to GABAergic interneurons. Model systems are of prime importance for adequately studying the pathophysiology of this disorder; however, existing in vitro models have limitations in producing patient-specific cells. The development of induced pluripotent stem cell (iPSC) technology has provided a novel opportunity for the effective production of disease-relevant cell types while preserving the molecular traits of the patient. In this thesis, the differentiation protocol established by Nicholas et al. (2013) was used to promote the development of interneurons derived from iPSCs. To enhance the efficiency of differentiation, the protocol was modified with the use of small molecules combined in different ways. The end result of the differentiation was characterized using immunocytochemistry (ICC) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The combination of molecules that produced greater efficiency in differentiation was selected, and the optimized protocol was carried out with iPSCs derived from an AD patient harbouring the APP Swedish mutation. The differentiation of cortical interneurons, demonstrated by the expression of pan-neuronal and specific GABAergic neuronal markers, signifies the successful generation of differentiated interneurons in the context of AD. AD iPSCs upregulated several markers related to AD pathology, such as APP and BACE1. However, the cell lines tolerated the small molecules differently, and thus, the protocol needs more optimization in the future. In summary, iPSC-based differentiation protocols are capable of producing disease-specific cell types that would be helpful in developing accurate AD models for revealing the mechanisms of Aβ pathology.
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(2023)The Arctic region is experiencing an intensification in the hydrological cycle due to climate change. Lakes in the Arctic respond quickly to environmental changes and act as archives to past climates. Naturally occurring stable isotopes of water, specifically the isotopes of oxygen and hydrogen, provide a valuable tool for investigating local hydrological conditions and reconstructing past climates. In this study, stable isotopes of water in Värriö, Northeastern Finland, were analyzed to gain insights into the local hydrology and assess the use of palaeoclimatological methods for reconstructing past climates. Precipitation, groundwater, and lake water were analyzed to characterize the local isotope hydrology. To assess the reconstruction of past climate conditions, a set of modern chironomid head capsules were collected and analyzed for their isotopic composition. Chironomid head capsules are commonly used to reconstruct past climate conditions. The results indicated that precipitation in Värriö is sourced from the Barents Sea to a considerable extent, which has implications for the isotopic composition of surface waters. The isotopic composition of lake water in Kuutsjärvi was found to reflect the precipitation isotopic composition well due to a lack of evaporative enrichment. The study also noted the seasonal effects of spring thaw on the lake, and the contribution of groundwater as a controller of these effects. The analysis of chironomid head capsules in this study yielded values that differed from present-day conditions. The possible reason for the offset in values was explored, but not identified. This highlights the importance of accurate calibration of chironomid head capsule values and knowledge of chironomid ecology when using this method for palaeoclimatological research. Overall, this study demonstrates the utility of stable isotopes of water for characterizing local hydrological conditions and reconstructing past climates.
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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)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)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)Due to population growth, urbanization, and increase in life expectancy, the urban population is growing, and by 2050 68% of the global population is expected to live in urban areas. Even though the air quality in urban settings has greatly improved in recent decades due to increased legislation, restriction, and monitoring, the negative health impacts associated with pollutants have not completely diminished. Air quality varies on a local scale due to urban form and function, that creates differences in experienced exposure among individuals. These exposure differences among socio-economic groups have been studied, but no clear consensus has been found, as the results have been very diverse and even contradictory. Therefore, conducting local level studies is important in order to identify local patterns of exposure and to recognize them in urban planning. However, previous literature on the topic in Finnish context is lacking. This thesis studies interpolated air pollutant exposure among one susceptible socio-economic group – the elderly – and aims to identify possible hotspots of both in Helsinki, Finland. The distribution of the elderly and air quality is assessed through Moran’s I calculations. Global Moran’s I is used to assess for spatial autocorrelation, and local Moran’s I is applied to identify local clusters. To further examine the relationship, correlation coefficients are calculated through Spearman’s rank correlation coefficient. According to the results, there is a weak positive correlation between the elderly and air quality, indicating that generally air quality tends to be worse when the number of elderly people increase. However, the relationship is stronger among younger age groups, although the differences between age groups is very small. The exposure was also assessed through overlapping high value clusters, which indicate that elderly clusters in the city center are located in areas with low air quality, while elderly clusters in Lauttasaari and Vuosaari are located in areas with good air quality. Previous studies regarding the relationship between age and air pollution exposure have been contradicting in different cities, and therefore these results provide important knowledge about the problem specifically in the context of Helsinki. Additionally, the results are be observed in the light of the larger discourse around socio-economic status and air pollution, but further studies on the topic are still needed. Including multiple socio-economic variables and the dimension of negative health outcomes would aid in identifying 1) the most important socio-economic factors in the context of negative health outcomes associated with air pollution, and 2) those areas where multiple important socio-economic factors and low air quality are overlapping and therefore might have higher risk for negative health outcomes.
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(2023)Forests play a key role in mitigating climate change and maintaining biodiversity. The ability of forests to sequester carbon dioxide and store it in wood biomasses and soils reduces the amount of carbon dioxide in the atmosphere. However, forests are cut down for various reasons, such as economic ones, releasing carbon dioxide from the trees into the atmosphere. One way to combat climate change and biodiversity loss is to provide forest owners a voluntary incentive scheme that provides a new objective for forest owners to use their forests. The use of forests in the future will be decided by the new forest owners, i.e., the younger generation of forest owners. For this reason, it’s important to study their preferences for a voluntary incentive scheme. The study examined the characteristics of absentee and non-absentee forest owners under the age of 40 and compared the preferences for a voluntary incentive scheme directed to these two groups. The survey response rate was low (7,3%). Choice experiment method and a binary logistic regression model was used to find out the forest owners’ preferences in relation to accept the programme. In the binary logistic regression model, absentee residence was the only factor that positively and reliably increases the acceptance of the programme. Absentee and non-absentee forest owners appreciate similar aspects of forest property, for example relaxation and financial security. The biggest difference between these two groups came with consideration of forestry work and/or wood for household as nonabsentee forest owners valued that aspect higher. The study points out that knowledge of a METSO programme is relatively low, as 35% of absentee and 23% of non-absentee forest owners who responded have heard of the programme. Some young forest owners may not have a clear idea on how to manage forests, because forest ownership is new to them and therefore it is often difficult for novice forest owners to know which forest management practices to apply in one's own forests. According to the study, economic income from the forest property is important, but it isn’t an important source of economic security for a large number of young forest owners, especially when the share of absentee forest owners’ characteristics and preferences are on the rise among forest owners.
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(2023)In this master’s thesis project, I studied the association of lipid molecules phosphatidylinositol 4-phosphate (PI4P) and phosphatidylinositol 3-phosphate (PI3P) with autophagy in neurons. One of the aims of the study is to determine the level of basal autophagy in primary hippocampal neurons and to come up with a protocol for autophagosome observation without forcing radical changes in cell culture conditions. Other mammalian cells have extremely weak basal autophagy, but they increase it significantly in response to starvation, for example. However, neurons are extremely sensitive to any changes in their surroundings. They change their morphology, behaviour and biochemical properties, and often they simply do not survive. Therefore, the goal is a protocol for successful autophagy observation with minimal external influence. Despite the debate around basal autophagy in neurons, I observed high levels of basal autophagy in neuronal cells incubated in media without supplements. Also, my observations revealed that the inhibition of the last step of autophagosome processing with Bafilomycin A1, was enough to cause the massive accumulation of large autophagosomes. Results demonstrated that primary hippocampal neurons exhibit high levels of basal autophagy, suggesting that on the contrary to other mammalian cells neurons might not have enough potential to increase autophagy when it is induced pharmacologically or by stressful conditions. This would explain why autophagy induction is often claimed to be ineffective for neuronal cultures. The main goal is to observe and compare PI4P presence on autophagosomes in normal conditions and when autophagosome:lysosome fusion is inhibited with Bafilomycin A1. The side goal is to observe PI3P presence on autophagosomes as well. I transfected primary hippocampal neurons with fluorescent probes for PI4P or PI3P as well as for autophagosome-related protein LC3. Localization data was collected with live-cell imaging on a confocal microscope. As expected, PI3P was not detected on autophagosomes located in soma. It is involved in the initial vesicle biogenesis in distal axons but not in later events taking place closer to the cell body. PI4P showed high degree of colocalization with LC3, indicating PI4P presence on autophagosomes, but only when the fusion was presumably inhibited by Bafilomycin A1. These results suggest that PI4P appears on autophagosomes either as a result of compensatory pathway, where autophagosomes fuse with late endosomes instead of lysosomes; or as a molecule normally involved in autophagosome:lysosome fusion. Literature supports the latter explanation, but it cannot be confirmed without further research. These results give an insight into PI4P role in neuronal autophagy and might be relevant for the future research of autophagy disruption and aggregate accumulation in neuronal diseases as a consequence of abnormal lipid signalling, lipid metabolism and transport.
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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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(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)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)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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