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The objective of this thesis is to study resilient urban housing business ecosystems and the role and use of nature-based solutions (NBS) in these ecosystems. Thesis aims to gather knowledge on how nature-based solutions are perceived in urban residential building and planning regime and how these solutions are valued to increase urban resilience. Thesis aims to provide knowledge on who are the actors in key role in designing, implementing, or using nature-based solutions in the case cities urban built environment and residential buildings of the business ecosystem. The benefits from nature-based solutions are presented and challenges hindering the mainstreaming of nature-based solutions as well as ways to overcome them are addressed. This thesis is a qualitative study with an empirical research approach. The empirical part of the study consists of data collected from 11 expert interviews, and two expert workshops. Altogether the empirical data corpus consisted of 15 transcripts. The interviews were semi-structured, thematic interviews where experts from different organizations of urban planning and construction industry were interviewed. Two separate workshops were held during August of 2023 in both case cities Helsinki and Turku. Workshops consisted of researcher presentations and focus group work, and the expert participants represented versatility of the field. Study applies reflexive thematic analysis method for qualitative data analysis. It is a systematic and flexible method that is used for identifying, analysing, and reporting meaning-based multifaceted and conceptual patterns within data by generating codes and themes. Several actor groups and key actors were identified based on the analysis. Also, an open role for a champion was recognized from the analysis. Several benefits derived from NBS and barriers for mainstreamed use were identified. Multiple solutions such as land use planning, urban governance practices including green factor, and economical incentives help to increase use of NBS in urban settings, and to answer the future of more resilient city. Urban resilience can be increased through inclusion of NBS and the associated delivery of ecosystem services in urban areas. Urban greenery and green spaces are highly relevant for well-being of residents. A holistic approach for urban planning and residential housing building is called for with increase in implementation of NBS. City should be designed for people as well as to other species. Experts share a vision of greener and more sustainable city where nature becomes one with the city, and city with the nature. There is still need for more research on long-term review of follow-ups and next steps taken from pilot projects to answer how nature-based solutions could be transferred from experimentations for everyday use and how this knowledge could be transferred for wider audiences.

Land-use change stands behind the current biodiversity crisis and all it entails in terms of ecosystem services. Guinea-Bissau, in West Africa, is originally characterized by a forest- savanna mosaic biome. However, while savannas have long been planted with rice, both rice paddies and forest remnants are now being converted into cashew monocultures – the only cash crop in the country – at unprecedented rates. The ecological impact of such rapid change is largely unknown. To help fill this gap, we examined how three diversity metrics – rarefied species richness, abundance and composition – varied across forest remnants, cashew orchards and rice paddies for amphibians and reptiles in northern Guinea-Bissau. To do so, visual encounter surveys were carried across 21 sampling sites, seven of each habitat type. A total of 703 amphibian and 266 reptile encounters was recorded from nine and 14 taxa, respectively. The results show class-specific responses to habitat type. Amphibians’ diversity in forest remnants and cashew orchards was similar across all metrics, but rice paddies had a higher abundance and unique composition compared to forest remnants. Reptiles’ abundance was highest in cashew orchards and this habitat had a distinct composition, when compared to forest remnants. Rice paddies sustained both lower reptile richness and abundance. Overall, our results are not in agreement with the expected detrimental impacts of cashew expansion, which might be due to the still high heterogeneity of habitat types within the landscape. Rice paddies proved particularly important for amphibians, and for open-habitat reptiles, boosting overall species diversity. In face of the eminent habitat conversion, maintaining heterogeneous landscapes, including the persistence of both forest remnants and rice paddies, will allow minimizing biodiversity loss in West Africa.

Tiivistelmä – Referat – Abstract Celiac disease (CD) is a serious lifelong condition, in which the immune system attacks an individual’s own tissue when eating gluten. This leads to inflammation and damage to the small intestine. Celiac disease often goes undiagnosed because many of its symptoms are nonspecific. The prevalence of combined undiagnosed and diagnosed CD is estimated to affect 1 in 100 people throughout Europe and USA. CD is a polygenic disease, it is known that the human leukocyte antigen (HLA) system plays a crucial role. HLA-DQ2/DQ8 risk allele genotyping screening test from a whole blood sample (B -HLAKeli) is routinely used to estimate the genetic risk of a patient having CD. HLA genotyping test result is routinely used to rule out celiac disease rather than confirming it; if an individual does not have celiac disease related risk alleles, it is very unlikely that he or she has celiac disease. The Celiac disease diagnosis decision making process is based on the classic triple combination of serological antibody tests, the HLA-DQ2/DQ8 genotyping test and duodenal biopsies. The aim of this master’s thesis was to study evaluate how the two different risk classification praxis for HLA-DQx.5 allele used for celiac disease diagnostics in SYNLAB Finland and Estonia central laboratory and in SYNLAB Suomi central laboratory might influence the clinical process and final diagnosis. In SYNLAB Suomi central laboratory HLA-DQx.5 is classified and interpreted as a risk allele predisposing to celiac disease. In SYNLAB Finland and Estonia central laboratory this allele is classified as CD-non-risk-allele based on recommendations in international guideline. In addition, the aim was to get a general understanding of celiac disease prevalence and risk allele distributions among the study population. From the study population of 196 celiac disease suspect patients, 9% had a celiac disease positive laboratory result and the HLA risk genotype distribution among positive cases was well aligned with the expected values described in the literature. Study results indicated that there’s no additional clinical value if HLA-DQx.5 is classified as a celiac disease predisposing risk allele; the study data implies that it is very unlikely to find celiac disease positive cases from laboratory test perspective among HLA-DQx.5 carriers. Based on the study, approximately 7% of the celiac disease suspects carry the allele HLA-DQx.5 and therefore probably go through additional celiac disease related laboratory testing if this allele is interpreted as a risk allele. According to the study findings and general recommendations based on international guideline of celiac disease diagnosis, it seems that there is no clear clinical benefit if HLA-DQx.5 is classified as a CD risk allele.

High-grade serous carcinoma (HGSC) is the most common and lethal subtype of ovarian cancer. To date, HGSC has typically been diagnosed late, and the survival rate is poor. Relapses are common despite standardised treatment options, and platinum-based chemotherapy resistance remains frequent. The tumours are generally heterogeneous, which makes HGSC complex. Molecular mechanisms of tumour initiation, progression and chemoresistance are insufficiently understood. Thus, efficacious treatment is challenging, and current options do not help some patients. In addition, a population of cancer cells having stem cell-like properties are suggested to play a role in tumour initiation, progression and chemoresistance. There is an urgent need to better understand prognostic biomarkers and treatment responses in HGSC. With diverse analytical methods, the treatment-unresponsive patients and their outcomes could be identified by predictive biomarkers. This thesis aimed to validate potential tissue biomarkers associated with cancer stem cells and poor prognosis in HGSC, evaluate the usability of the RNAscope technique and briefly review the hypotheses on cancer stem cells. Four putative biomarkers were studied: ALDH1A1, BMI1, MYC and SOX2. The RNAscope technique was used to detect and quantify the biomarker expression. Using diagnostic tumour tissue specimens from 95 patients allowed capturing the expression in situ. With comprehensive clinical information, we could test whether the biomarkers distinguished patients with similar background information but different outcomes. This thesis shows that BMI1 could be a potential prognostic biomarker in high-grade serous carcinoma. The results provide information about the expression patterns of previously identified potential HGSC stemness markers. Proteomics studies such as immunohistochemistry could provide complementary information. When the molecular mechanisms and prognostic markers are better understood, they will provide a promising opportunity to develop novel diagnostic methods for predicting the outcomes and deciding treatments for this complex disease.

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.

The increased rates of population growth and urbanization worldwide raises the question of food security and self-reliance in cities. In view of this situation, in recent years there has been a re-emergence of urban agriculture in its traditional form and in new variations, such as on urban rooftops. A number of rooftop urban farms exist in the world; however, very few studies have been done to establish the quality of crops they produce, specifically concerning the concentrations of contaminants. The main purpose of this study was to investigate levels of contamination in edible plants grown on urban rooftops. I determined concentrations of polycyclic aromatic hydrocarbons (PAH) and trace metals in the biomass of three types of horticultural crops grown in the city of Helsinki, Finland. Lettuce, radish and peas were planted on five rooftops in various areas of Helsinki and control samples were acquired from local food stores and markets. Both groups of crops were analyzed for concentrations of 11 trace elements using the Elan 6000 ICP-MS and 16 PAHs using Shimadzu GC-MS-QP2010 Ultra system with the AOC-20i /AOC-20s autosampler. Additionally, lettuce and pea samples from the roofs were analyzed washed and unwashed to establish levels of particulate contamination on the surface of plants that can be mechanically removed through washing. Results obtained suggest that concentrations of PAHs and trace metals in rooftop vegetables in Helsinki are very low and the differences in their concentrations compared to control (store) samples are insignificant. This demonstrates that the consumption of vegetables produced in uncontaminated soil on urban roofs in Helsinki is safe. All samples showed concentrations well below the safety limits for heavy metals and PAHs established in the European Union (EC, 2006). Finally, there was a difference in concentration of PAHs and trace metals between washed and unwashed samples, however most of the results did not show statistical significance.

Social behaviour can be divided into neutral, positive, and negative, depending on the social context. Positive social behaviour involves affiliative prosocial interactions that encourage social and emotional cohesion. Rat (Rattus norvegicus) is a globally distributed common rodent species adapted to living near humans. Rats are intelligent and social animals with reciprocal prosocial behaviour. However, research on the social behaviour of rats is concentrated in laboratory settings and very little is known about the social behaviour of free-living rats. Rats arouse strong prejudice in humans and are considered aggressive. Despite a long history of coexistence, there are still strong conflicts between humans and rats. In this study, I used camera trap data to investigate the types of social behaviour in free-living rats and the time allocation of different behaviours. I investigated how the rats' behaviour is divided into socially neutral or positive and negative behaviour in relation to the total time spent on the behaviour. I also investigated the types of social behaviour that occur when rats approach each other and the frequencies of these different behavioural models. For the behavioural analyses, I used data-driven ethograms that I made and the behavioural analysis software BORIS. I found that the majority (over 96.2 %) of the social behaviour of the free-living rats in my study population was neutral or positive behaviour as measured by the duration of the behaviour categories. I also found that the most significant proportion of social behavioural models in rats was socially neutral or positive. Agonistic behavioural models were rare and occurred mostly between adults. In contrast, rats exhibited a moderate amount of prosocial behaviour, particularly in the form of food sharing and muzzle touching. My study brings new information to the limited previous research on the behaviour of free-living rats. The results suggest that most of the social behaviour in free-living rats would be neutral or positive behaviour, and agonistic behaviour in rats would be relatively rare. To the best of my knowledge, this work is the first study to analyse the social behaviour of free-living rats from camera trap data. Objective research data on the social behaviour of rats may mitigate prejudice against rats and attitudes towards rats may become more positive. This can mitigate conflict between humans and rats and promote peaceful coexistence. This work can be used as a pilot for future studies. The information this work provides can also be used, for example, to educate people about their attitudes towards rats.

In Sápmi, the traditional homelands of the Indigenous Sámi, climate change and green transition have created together a double burden for the Arctic ecosystems and the Sámi. As an effort to mitigate the climate change, the transition towards green sources of energy and mineral intensive technologies have created conflicting interests for land use in Sápmi, as extractivist activities have been located for instance to their traditional reindeer pasture lands. This thesis focuses on representations of Western edited media about green transition related extractive activities in Sámi context. Construction and operation of Fosen wind farm in Norway and expansion of mineral extraction in Giron, Sweden, act as examples of such activities. The research question is: what issues the Western edited media represents when discussing extractive activities regarding green transition, in the Sámi context? The thesis derives from the identified research gap of the matter, as this kind of research regarding the Sámi has not been conducted before. The thesis uses inductive thematic analysis to identify issues the news media articles represent regarding cases of Fosen and Giron. The research data consists of 35 news articles, published between 2016-2024. The applicable case examples were identified in data collection as illustrating the green transition related extractivist activities having significant impact on the Sámi communities. Through thematic analysis, six themes were identified and further analyzed through the framework of Indigenous Environmental Justice (IEJ). The analysis shows that the media represents green transition related extractivism in both negative- and positive lights. Whereas wind power and mineral extraction are represented as essential drivers for sustainable future, they also have negative impacts for the ecosystems in Sápmi and to the Sámi culture and livelihoods. The activities are represented as causing disputes between the Sámi and other stakeholders, due to conflicting interests of land-use and the Sámi’s experiences of violation of rights and unfairness. The activities taking place in Sápmi are often represented as continuation of Western colonialism, planned without sufficient consultation and involvement of the local Sámi communities. Yet, the Sámi are represented as solution-oriented, aiming to actively protect their traditional lands. The struggle of the Sámi with Western extractivism was also represented as part of wider global struggle of Indigenous people, whose traditional homelands these activities have penetrated to. These issues identified support the notions of IEJ about Western legal systems as failing to resolve environmental injustices and current extractivist activities as a form of on-going colonialism. The analysis also shows that the provision of multiple ontologies and legal orders, intergenerational- and other-than-human justice and acknowledgement of the distinct legal status of Indigenous peoples are needed, as argued by IEJ scholars. In the future, as the extractivist activities in the Arctic are expected to intensify, there is an urgent need for critical assessment of the manner the green transition is currently carried out in Western societies, participatory evaluation of impacts of the extractive projects and emphasis on aspects of fairness.

Antibioottien ylenmääräinen käyttö ja uusien antibioottien puute ovat johtaneet antibiooteille vastustuskykyisten bakteerien aiheuttamien sairauksien yleistymiseen. Lisääntynyt antibioottiresistenssi on maailmanlaajuinen ongelma, joka uhkaa globaalia terveyttä ja ruoan turvallisuutta. Staphylococcus aureus ja Pseudomonas aeruginosa ovat sairaaloissa yleisiä infektioita aiheuttavia mikrobeja. Metisilliiniresistentti S. aureus eli MRSA pystyy aiheuttamaan infektioita lähes missä tahansa kudoksessa. P. aeruginosa on akvaattisissa ympäristöissä yleinen mikrobi, joka on usein luonnollisesti vastustuskykyinen useille antibiooteille. Lisäksi molemmat bakteerit kykenevät biofilmin muodostamiseen, joka heikentää entisestään antibioottien tehoa. Jätevesien puhdistamoilla on yleisesti havaittu esiintyvän S. aureus- ja P. aeruginosa -bakteereita, mutta suurin osa tutkimuksista on keskittynyt tulevan ja käsitellyn jäteveden mikrobimääriiin ja/tai aktiivilietteeseen. Jätevesillä on ehdotettu olevan merkittävä rooli antibioottiresistenssin kehittymisessä ja leviämisesessä. Jätevesien puhdistamot keräävät yhteen kotitalouksien, teollisuuden ja sairaaloiden jätevesiä ja luovat niiden mukana tulleille mikrobeille tilaisuuden sekoittua ja vaihtaa geneettistä materiaalia, kuten antibioottiresistenssigeenejä. Toisaalta ne ovat myös paikkoja, joissa antibioottiresistenssejä bakteereita vastaan voi kehittyä uusia antimikrobiaalisia aineita tuottavia mikrobeja. Pro Gradu tutkielmani on osa TWIN-A konsortion hanketta ”uusia antibiootteja jätteistä”, jonka päämääränä on uusien antimikrobiaalisten aineiden löytäminen jätevesistä ja teollisista komposteista. Pro Gradu tutkielmassani kartoitan S. aureus ja P. aeruginosa bakteerien esiintymistä jätevedenpuhdistamoiden eri prosesseissa reaaliaika-PCR:n perusteella. Tutkimukseni tuloksia voidaan käyttää hankkeen jatkotutkimuksissa sekä jätevedenpuhdistamoiden riskinarvioinnissa. S. aureus -bakteeria kartoitettiin metisilliiniresistenttiä koodaavan mecA-geenin avulla ja S. aureus -bakteerille spesifistä nukleaasia koodaavan nucA-geenien avulla. P. aeruginosa -bakteeria kartoitettiin gyrB- ja ecfX-geenien avulla. Lisäksi näiden geenien kartoituksessa oli apuna koettimet.GyrB- ja ecfX-geeneissä olevilla muutoksilla on havaittu olevan vaikutusta bakteerin virulenssikykyyn. Kartoitettuja geenejä havaittiin esiintyvän yleisesti jätevedenpuhdistamojen prosesseissa, mutta pitoisuudet olivat alle määritysrajan. MecA-geenin esiintymisfrekvenssi oli nucA-geeniä suurempi, joka voi johtua siitä, että mecA-geeniä esiintyy myös muilla stafylokokki-lajeilla, kun nucA-geeni on spesifinen S. aureus-lajille. Myös gyrB-geenin esiintymisfrekvenssi oli korkeampi kuin ecfX-geenin, joka selittynee gyrB-geenin heikommalla lajispesifisyydellä. Kaikkien kartoitettujen geenien esiintyminen oli painottunut välppeeseen, aktiivilietteisiin, raakalietteeseen, palautuslietteeseen ja tiivistämölietteisiin. Välppeen läheinen kontakti ihmisen kanssa ja suuri orgaanisen aineen määrä selittävät korkeita esiintymisfrekvenssejä tässä prosessissa. Mikrobeille otolliset olot ja mikrobien sorptio aktiivilietteeseen selittävät kartoitettujen bakteerien yleisyyden aktiivilietteissä ja sen jälkeisissä prosesseissa mädättämölle asti. Mädättämöllä anaerobinen mädätys johtaa kartoitettujen geenien vähenemiseen. Mädättämöliete käsitellään Suomessa pääosin kompostoimalla, jossa lämpötilan nousu tappaa suurimman osan patogeeneistä. Kartoitettujen geenien poistuminen jätevedenpuhdistusprosesseista aktiivilietteen mukana, selittää myös geenien matalamman esiintymisfrekvenssin käsitellyssä jätevedessä verrattuna tulevaan jäteveteen. Tulosten perusteella kartoitetut bakteerit ja niiden antibioottiresistenssigeenit eivät aiheuta riskiä ympäristölle. Vaikka havaitut pitoisuudet olivat alle määritysrajan on kuitenkin hyvä pitää mielessä, että ympäristötekijöistä riippuen antibioottiresistenssigeenit ja bakteerit voivat kertyä ympäristöön ja sopivissa olosuhteissa lisääntyä ekspotentiaalisesti. Multiresistenssien bakteerien on myös havaittu selviävän paremmin jätevedenpuhdistusprosesseista, jonka vuoksi tilannetta olisi hyvä seurata tulevaisuudessa.

Tiivistelmä – Referat – Abstract Ikääntymiseen liittyvien biologisten ilmiöiden, kuten rappeutumisen ja sairauksien tutkiminen on ensiarvoisen tärkeää, koska näistä ilmiöistä on haittaa niin yksilölle kuin koko yhteiskunnalle. Erityisen kiinnostavaa on, jos sairaudet ja rappeutuminen pystytäisiin parantamaan tai niiden haitallisia vaikutuksia voitaisiin vähentää. Ikääntymiseen voidaan yhdistää monia vakavia sairauksia kuten hermostorappeumasairaudet, syöpä ja diabetes. Hermostorappeumasairauksille on tunnusomaista proteiiniaggregaattien muodostuminen. SBC003-yhdiste on luonnon yrtistä eristetty molekyyli, joka on potentiaalinen lääke hermostorappeumasairauksiin. Aikaisemmin tehdyt tutkimukset hermostorappeuma sairausmalleilla osoittavat yhdisteellä olevan voimakas konsentraatiosta riippuvainen hermosoluja suojaava vaikutus. Malliorganismit ovat tärkeitä, koska niillä pystytään testaamaan potentiaalisten molekyylien vaikutusta vahingoittamatta kuitenkaan ihmistä. Hiivasta on tullut mielenkiintoinen malliorganismi ikääntymisen ja ikääntymiseen liittyvien sairauksien tutkimuksessa. Monet biologiset prosessit ja aineenvaihduntareitit ovat konservoituneet hiivasta aina ihmiseen asti. Lisäksi geneettiset muutokset on helppo jäljittää. Ikääntymisen tutkimisessa leivinhiiva (Saccharomyces cerevisiae) on osoittautunut erinomaiseksi malliorganismiksi. Hiivan kronologinen ikääntyminen on osoittautunut myös hyväksi menetelmäksi tutkittaessa solujen post-mitoottista ikääntymistä. Hiivasoluissa pystytään havaitsemaan nopeasti, edullisesti ja helposti proteiiniaggregaattien aiheuttamat haitalliset vaikutukset. Käytettäessä hiivaa malliorganismina tutkimuksessa pystytään luomaan suora linkki geenien ja kemiallisten yhdisteiden välille. Hiivalla tehdyt solujen sairausmekanismien tutkimukset ovat vertailukelpoisia ihmisten sairauksien kanssa. Nämä seikat tekevät hiivasta kiinnostavan malliorganismin myös hermostorappeumasairauksien lääkeainetutkimuksessa. Työn tavoitteena oli selvittää, voidaanko hiivasairausmalleja käyttää SBC003-yhdisteen vaikutuksien arvioimiseen hermostorappeumasairauksissa, ja onko tutkittavalla yhdisteellä pelastava vaikutus haitallisia aggregaatteja muodostavia proteiineja vastaan hiivasairausmalleissa. Lisäksi tarkoitus oli tutkia, onko SBC003-yhdisteellä vaikutusta ikääntymisestä aiheutuvaan elinvoimaisuuden heikkenemiseen hiivasoluissa. Tutkimuksissa käytettiin seuraavia menetelmiä ja koejärjestelyjä 1. spottitestejä ja 2. elinkiertotestejä ravistelukasvatuksina, joiden elinvoimaisuutta mitattiin näytteillä, joita puolestaan analysoitiin edelleen Bioscreen-kasvatuksia apuna käyttäen. Spottitestien ja elinkiertotestien tuloksien mukaan SBC003-yhdisteellä saattaa olla pelastava vaikutus haitallisia FUS-aggregaatteja vastaan hiivan ihmisen sairausmallin soluissa. Tutkimustulosten mukaan SBC003-yhdisteellä on solun elinvoimaisuutta parantava vaikutus soluihin, jotka rappeutuvat ikääntymisen seurauksena. Saatujen tulosten varmentamiseksi pitäisi elinkierotestit ja spottitestit toistaa ja lisäksi tehdä sekä geneettisiä että epigeneettisiä tutkimuksia.