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In this thesis, the migration patterns of the legacy pesticide called atrazine were studied in the Laune aquifer in Lahti, Finland, using the MODFLOW groundwater modelling program connected to the MT3D tool. Three models were built for the thesis. In the first model, the migration of atrazine in the Laune aquifer was studied by simulating the steady release of 1.22 µg/L atrazine concentration from sediments in the Lahti railway area over 15 years. In the second model, the depletion of atrazine from soil deposits was studied over time in both sudden and gradual depletion scenarios for 10 and 30 years. In the third model, the effect of pumping contaminated groundwater from an extraction well and injecting remediated water back into the aquifer from another well was investigated on the atrazine concentration in groundwater in the study area for 15 years. Concentrations of atrazine in the aquifer either increased or decreased from the baseline concentrations in the first model. In certain areas in Laune, atrazine concentrations exceeded the EU safe limit values during the whole modelling period. In the second model, the dilution of atrazine was relatively slow, even in the scenario of sudden depletion. It can take decades for the groundwater concentrations to dilute to EU-safe limits once the limits have been exceeded. In the last model, the pumping and injection of remediated groundwater showed a decline in concentration of atrazine over time. However, the effects were only local. Regional effects would have required a higher number of injection wells covering a larger area. Modelling tools are an important part of ethical ecotoxicological research solving many logistical problems related to field studies. However, as the results are highly depend- ent on the parameters, the results should be critically evaluated and used as part of other research methods. In environmental restoration work, understanding and modelling the pa- rameters related to leaching risk can be used as part of risk management. Understanding the migration of stored pesticides into the environment, the development of environmental restoration methods, and preventive measures are crucial to securing clean drinking water quality and quantity in the future.

The taxonomy of the green macroalgal genus Monostroma is poorly known in the Baltic Sea region and worldwide.Two species of Monostroma are currently reported from the Baltic Sea: the cosmopolitan spring species Monostroma grevillei and a proposed endemic, free-floating summer species Monostroma balticum. However, previous work has highlighted the unclear taxonomic status of M. balticum, and some consider it a growth form of the cosmopolitan species M. grevillei or a monostromatic growth form of Ulva spp. No molecular data exists of M. balticum, and the morphological characteristics distinguishing this species from M. grevillei and similar species are unclear in the literature. The aim of this thesis is to explore the taxonomic status of M. balticum by firstly systematically reviewing the historical and contemporary literature, including the original description, to illuminate the current morphological circumscription of M. balticum and related species. Secondly, using DNA barcoding based on the tufA -marker, fresh collections of foliose monostromatic green algae from the Baltic Sea region are identified molecularly and put into an evolutionary context using phylogenetics. Thirdly, novel plastid genomes are produced from monostromatic green algae to explore the genomic features of these algae and to see if they aid in species delimitation or phylogenetic approaches. Based on the literature review, the morphological and ecological features used in specimen identification currently (micromorphology, free-floatingness and occurrence in summer) may not be enough for accurate identification, and especially the micromorphological features are quite vaguely described in contemporary literature making their use difficult in practise. All monostromatic specimens collected are identified using DNA barcoding as either M. grevillei, Kornmannia leptoderma or Ulva intestinalis, and those specimens mostly resembling the original description of M. balticum are recovered as U. intestinalis. Plastid genomes were produced from M. grevillei, K. leptoderma and U. intestinalis, from the latter species separate genomes were generated from a typical tubular-morphology specimen as well as a “M. balticum”-morphology specimen. M. grevillei and K. leptoderma plastids were unusual in being large, inflated by many introns and intrageneric regions and having many rearrangements. Produced U. intestinalis plastomes are similar and resemble previously published Ulva genomes. The accurate identification of M. balticum -like specimens is discussed, and for future work DNA barcoding is suggested to be the main tool for specimen identification. This thesis provides evidence towards a previous hypothesis that M. balticum is not a distinct species but a specific growth from of U. intestinalis. Investigating historical herbarium specimens, including original material, using molecular methods is proposed to verify if M. balticum should be synonymised formally with U. intestinalis. The potential drivers of the shift in growth form of U. intestinalis are discussed. Finally, the plastid genome landscape in these foliose green algae is discussed.

This body of research focuses on establishing a drug screening pipeline for discovering drugs which increase the differentiation of pluripotent stem cells into cardiac myocytes, known as cardiogenic molecules. Cardiomyocytes can be utilized in regenerative medicine by offering a platform for testing molecules or drugs which may increase cardiomyocyte proliferation and for using cardiomyocytes produced outside of the body for clinical transplant, in order to heal the damage caused by heart attacks. Building on known models and developmental pathways three assays were designed and implemented for in vitro cardiogenic molecule screening. A pipeline comprised of three primary screening systems; an embryoid body (EB) model, a cardiomyocyte directed differentiation model, and a magnetic activated cell sort (MACS) model. The MACS model uses the cell surface receptors Fetal Liver Kinase 1 (FLK1) and/or Platelet Derived Growth Factor Receptor alpha (PDGFRα) as the most practical platform for screening drugs against an enriched mesodermal population of cells. The MACS system was confirmed with flow cytometry to ensure the enrichment of Myl2-eGFP+ (ventricular cardiomyocytes) cells in the FLK1+ cells. Furthermore unique known molecules help elucidate the molecular mechanisms governing cardiomyocyte differentiation, measured by cardiomyocyte purity in in vitro models. Also demonstrated are assay controls which decrease purity and acts as negative controls for the MACS assay such as a late stage GSK-3 Inhibitor treatment used to constitutively activate the canonical Wnt/β-catenin pathway and effectively reduce the cardiomyocyte proliferation. Additionally, an early stage Wnt Inhibitor compound IWP-4 was used as a potential positive control effectively blocking late stage activation of canonical Wnt/β-catenin pathway and increase the in vitro purity of cardiomyocytes. These controls provide two important reference points for the many molecules screened over the course of these experiments for the 3i Regeneration project. Additional molecular inhibitors are used to elucidate the mechanism of action within the MACS cells; including a Sonic Hedgehog inhibitor (cyclopamine), an NKX2.5 activator (ISX-9) and a novel small molecule (C1). These models act as an effective pipeline bringing a potential drug through first an EB model, followed by a cardiomyocyte enriched model, to finally a MACS model targeting FLK1. This pipeline tests the molecules against conditions of increasing resemblance to the native microenvironment of a cardiomyocyte.

Phylogenetics is the study of the evolutionary history of life on Earth, which has shifted from relying on morphological characteristics to molecular data with the advancements in sequencing technology. Understanding Earth's biodiversity is crucial, as it has important implications for conservation, ecology, and evolution. Speciation occurs when barriers restrict gene flow between previously interbreeding populations. One such barrier may be endosymbiotic bacteria, like Wolbachia, which can manipulate host reproduction and create incompatibilities between host lineages. Wolbachia is widely distributed among arthropods and is the most common endosymbiont of insects. The bacterium is known to alter its hosts' biology, serving as a master manipulator of reproduction. Wolbachia-induced phenotypes can lead to the divergence of host lineages and speciation events. The genus Cotesia (Hymenoptera: Braconidae: Microgastrinae) is a highly diverse group of parasitoid wasps, where several species parasitize Melitaeini butterflies, including two cryptic species complexes. The current phylogenies of these species are 20 years old and need an update, as they were built with few markers and contain unresolved nodes. Wolbachia has been observed in this system, but its role remains largely unexplored. In this study, I aim to reconstruct the phylogeny of Cotesia species parasitizing Melitaeini butterflies, using two mitochondrial markers and eight nuclear markers to update our understanding of the differentiation of the cryptic Cotesia species. Additionally, I screened the specimens for Wolbachia to determine its possible role in shaping the Cotesia host phylogeny. I expect different Cotesia lineages to carry divergent Wolbachia strains or have different infection statuses (infected vs. uninfected). With fresh Cotesia specimens collected from various locations in Europe, I amplified and sequenced two mitochondrial markers (16s, COI) and eight nuclear markers (18s, 28s, CfCN, CfEN, EF1A1, LwRh, SLD5, TCEB) for phylogenetic analysis. The phylogenetic analysis revealed two main clades: Clade A, where Cotesia acuminata forms a polyphyletic group, and Clade B, where Cotesia melitaearum forms a monophyletic group. Wolbachia was detected only in one species, Cotesia melitaearum Sp. G, where the strain has persisted for over 20 years. The strains infecting Cotesia belong to supergroup B and are all closely related. The close relationship and low infection rate suggest that Wolbachia is not responsible for the original divergence but may play an ongoing role in restricting gene flow between species. The updated phylogeny is in concordance with the previous works but also strengthens our understanding of the relationships within Clade B. Further work is required to resolve some relationships within Clade B and understand the cryptic species' divergence.

Luonnon monimuotoisuus on vähentynyt viime vuosina globaalisti. Puhutaan jopa kuudennesta massasukupuutosta. Myös Suomessa erityisesti vanhojen metsien sekä niitty- ja perinneympäristöjen lajistot ovat heikentyneet. Suurin syy monimuotoisuuden vähenemiseen on elinympäristöjen katoaminen ihmistoiminnan ja maankäytönmuutosten vuoksi. Suomen uhanalaisia lajeja uhkaavat eniten metsä- ja maatalous ja niiden myötä vähenevät lahopuun ja niittyjen määrät. Luontotyypeistä erityisesti jalopuulehdot ovat katoamassa. Osansa maa-alasta vievät myös vapaa-ajan harrastukset, kuten esimerkiksi golf. Golfkenttien vaikutus monimuotoisuuteen on jakanut mielipiteitä. Golfkentän ekologiseen arvoon vaikuttaa se, millaiseen ympäristöön se on rakennettu. Urbaanissa ympäristössä golfkenttä voi merkittävästi lisätä monimuotoisuutta päinvastoin kuin metsäiseen ympäristöön rakennettuna. Golfkentät ovat kuitenkin usein laikuittaisia sisältäen useita erilaisia, pienialaisia kaistaleita alkuperäistä luontoa. Tässä työssä selvitin golfkentän rakentamisen aiheuttamia vaikutuksia metsäekosysteemin alkuperäiseen eliöyhteisöön sekä golfkentän monimuotoisuutta itsessään sekä verrattuna ympäröiviin alueisiin. Lisäksi pohdin, miten monimuotoisuutta kentällä voitaisiin parantaa. Tutkimuskohteena oli Hirsalan golfkenttä Kirkkonummella Etelä-Suomessa. Kesän 2018 aikana tein kentällä luontokartoituksen määrittämällä kentällä havaitut kasvit, nisäkkäät, linnut, matelijat ja sammakkoeläimet, perhoset sekä maakiitäjäiset (Coleoptera: Carabidae). Maakiitäjäisiä keräsin myös kentän reuna-alueelta sekä kentän ulkopuolelta. Perhosten keräämiseen käytin valorysää ja kolmea syöttirysää, keräys kesti toukokuusta elokuuhun. Maakiitäjäiset keräsin kuoppapyydyksillä (yht. 93) samalla aikataululla. Muut taksonit määritin näkö- ja kuulohavaintojen avulla. Mallinsin perhos- ja maakiitäjäisaineistoilla kentän ja vertailualueiden lajistojen runsausjakaumia. Maakiitäjäisaineistolla vertaisin kentän, kentän reuna-alueen ja kentän ulkopuolisen alueen monimuotoisuuksia Shannonin-Wienerin ja Simpsonin diversiteetti-indekseillä. Kasviaineiston avulla tein golfkentän alueesta luontotyyppikartan QGIS- paikkatieto-ohjelmalla. Muut aineistot täydensivät tilastomenetelmillä saatuja tuloksia. Golfkentän saamat diversiteetti-indeksit olivat pienempiä kuin kentän reunalla tai kentän ulkopuolella saadut arvot. Golfkentän lajistojen runsausjakauma oli epätasaisin muiden alueiden runsausjakaumiin verrattuna. Kentällä dominoi aitosysikiitäjäinen (Pterostichus melanarius, 65 % kentän lajistosta), joka on tunnettu häiriöekosysteemien generalistilaji. Perhosaineiston runsausjakauma ei kuitenkaan poikennut vertailuaineistosta. Golfkentällä havaittiin myös uhanalaisia ja suojeltuja lajeja, kuten liito-orava (Pteromys volans) sekä kartioakankaali (Ajuga pyramidalis). Kentällä ja sen läheisyydessä havaittiin myös useita metsäisiä lajeja, joista osa käytti kenttää esimerkiksi saalistamiseen tai laiduntamiseen. Kentältä löytyi luontotyyppejä niin karuista kalliometsistä tuoreisiin kankaisiin ja pähkinäpensaslehtoon. Kentältä löytyi myös joitain haitallisia vieraslajeja, kuten keltamajavankaali (Lysichiton americanus). Kentän rakentaminen on heikentänyt ja muuttanut alkuperäistä metsäekosysteemin eliöyhteisöä. Kenttää voidaan pitää häiriöekosysteeminä, jossa generalistilajit viihtyvät spesialistilajien kadotessa. Alueella voi myös olla vielä jäljellä rakentamisesta aiheutuvaa paikallista sukupuuttovelkaa esimerkiksi kasvi- ja hyönteislajien suhteen. Kenttä yhdessä ympäröivän luonnon kanssa muodostaa laikuittaisen elinympäristön, joka mahdollistaa monien lajien ravinnonhankinnan ja pesimisen kentällä ja sen läheisyydessä. Kentän monimuotoisuutta voitaisiin parantaa lisäämällä kentällä lahopuun sekä niittyjen määrää. Luonnonkasvien lisääminen ja niiden hallittu hoitamattomuus voi lisätä hyönteisten ja kasvinsyöjien määriä ja näin edelleen vaikuttaa kaskadiefektin kautta ylemmille ravintoketjun tasoille. Myös lampien ympärille olisi hyvä jättää suojavyöhykkeet. Alkuperäisiä luontokaistaleita tulisi vaalia, erityisesti kentällä sisällä olevaa pähkinäpensaslehtoa. Kentällä esiintyvät haitalliset vieraslajit ja puutarhakarkulaiset tulisi poistaa, etteivät ne vie elintilaa alkuperäislajeilta. Pöntötyksillä voidaan myös lisätä yksittäisten lajien tilaa lisäämällä niille mahdollisia pesimis- ja levähdyspaikkoja.

Sleep is one of the most vital functions of newborns and infants, and it is essential for neuronal network development. Therefore, long-term sleep disturbances have been associated with growth delays and behavioral disorders. Commonly reported infant sleep disturbances, such as night awakenings and difficulties falling asleep, cause distress to parents. Yet, the development of infant sleep in the home environment has not been fully elucidated due to lack of objective measurement parameters. In the current study, we assessed the feasibility of a motion sensor, attached to wearable pants, and ECG textile electrodes to monitor sleep-related respiration and heart rate of newborns and infants. First, we compared signals recorded by the motion sensor’s measurement channels to the standard respiratory piezo effort belt’s signal during daytime EEG recordings. According to our results, the motion sensor’s gyroscope proved to measure respiratory rate most accurately, while the ECG signal transmitted by the sensor was reliable in interpretable sections. We then provided wearable garments and smartphones to families with infants to assess overnight home-use. Our results indicate that different sleep states could likely be identified based on respiration fluctuation visible in the gyroscope’s signals. Moreover, the wearable system was considered practical and easy to use by the parents. Future studies should focus on validating the sensor with clinically approved measures, in order to train the algorithms to automatically identify different sleep-wake states. By doing so, the wearable sensor could provide information on natural infant sleep structure development over long time periods. Additionally, clinical validation of the sensor may result in the development of a companion diagnostic tool for infant cardiorespiratory and movement disorders.

As a response to Arctic climate warming, Arctic vegetation is changing. Studies have shown a greening trend both in satellite-derived data (spectral greening) and in field measurements (vegetation greening). Some studies indicate that the increase in vegetation productivity in the Arctic is one of the drivers of the increase in organic carbon in lakes, lake brownification. The aim of this thesis is to bring more knowledge about this possible connection between vegetation change and lake brownification in a circumpolar context. My two main research questions are: 1) How has the summer terrestrial NDVI value, in short, the normalized vegetation index to estimate the amount of green vegetation, changed during the past 20 years in the study areas and is there variation between lake groups? and 2) How has the amount of organic carbon changed in the studied lakes? These questions are complemented by the following sub-questions: Have summer temperature or precipitation affected NDVI change? What is the relationship between summer NDVI and lake organic carbon, and between the change in temperature/precipitation and the change in lake organic carbon? I conducted a circumpolar study about multi-decadal greening and climate trends around 15 Arctic and subarctic lakes divided into five groups, using satellite-derived vegetation data (NDVI). I then compared these data with sediment data to study if potential greening has a connection to the lakes’ total organic carbon load. The study areas are located in South-Central Canada, Alaska, North Finland, Russia – Yakutia and Russia – Chukotka. I found that summer surface air temperature has increased significantly in all of the study areas during 1961-2018. Total summer precipitation has not significantly changed during the study period, but the trend has been positive in all study areas except for Russia, Chukotka. Winter precipitation has significantly decreased in Alaska, and in both of the Russian areas, and significantly increased in Jänkäjärvi, Finland during 1961-2018. NDVI has increased significantly in Jänkäjärvi (Finland), Rauchuagytgyn and Illerney (Russia, Chukotka) during 2000-2021. In these lakes the environmental variables were affecting NDVI. The connection between NDVI in the study areas and lake TOC was positive, but not statistically significant. The situation was the same for the comparison between temperature and TOC for most of the lakes. When comparing the change in summer and winter precipitation and the change in TOC, for most of the lakes, precipitation had decreased while TOC increased. In conclusion, the results indicate that environmental conditions are changing in the study areas and that in some areas that has led to an increase in summer terrestrial NDVI values. It may also be that catchment area greening can increase lake TOC. However, this connection needs more research, for instance with a larger sample size. This study with its varying results also supports the notion of heterogeneous Arctic environments.

Tiivistelmä – Referat – Abstract Sekajätteen koostumuksen tunteminen on tärkeää, kun kierrätystavoitteiden tiukentuessa suunnitellaan toimenpiteitä jätteen määrän vähentämiseksi ja kierrätyksen lisäämiseksi sekä kun arvioidaan toteutettujen toimenpiteiden vaikuttavuutta. Muovipakkausten erilliskeräys aloitettiin pääkaupunkiseudulla vuonna 2016 ja syksystä 2017 lähtien kaikki halukkaat asuinkiinteistöt ovat voineet tilata kiinteistölleen oman muovipakkausten keräysastian. Kiinteistökohtaisen keräyksen lisäksi kotitalouksien muovipakkauksia kerätään myös osalla pääkaupunkiseudun ekopisteistä, joihin muovipakkauksia voivat viedä kaikki alueen asukkaat, myös ne, joilla muovipakkausten erilliskeräystä ei ole järjestetty omalla kiinteistöllä. Tutkimuksen tavoitteena on selvittää, miten muovipakkauskeräyksen aloittaminen on vaikuttanut pääkaupunkiseudun kotitalouksien sekajätteen määrään ja koostumukseen sekä miten muovipakkausten määrä pääkaupunkiseudun kotitalouksien sekajätteessä on muuttunut muovipakkauskeräyksen aloituksen jälkeen. Tutkimuksessa selvitetään myös, miten muovipakkausten erilliskeräys omalla kiinteistöllä vaikuttaa muovipakkausten määrään sekajätteessä pääkaupunkiseudun isoilla yli 19 huoneiston kiinteistöillä. Tuloksia verrataan aiempiin pääkaupunkiseudun kotitalouksien sekajätteen koostumustutkimuksiin. Tutkimus toteutetaan keräämällä yli 15 000 pääkaupunkiseudun asukkaan sekajäte viikon ajalta ja lajittelemalla tutkimuskuormista otetut n. 100 kg:n kokoomanäytteet käsin. Otantamenetelmän käytetään ositettua otantaa. Kotitaloudet jaetaan viiteen eri tutkimusryhmään huoneistomäärien mukaan. Tutkimusryhmät ovat 1 huoneiston kiinteistöt, 2 - 4 huoneiston kiinteistöt, 5 - 9 huoneiston kiinteistöt, 10 - 19 huoneiston kiinteistöt ja yli 19 huoneiston kiinteistöt. Yli 19 huoneiston kiinteistöt jaetaan vielä kahteen ryhmään sen mukaan, onko niissä järjestetty kiinteistökohtainen muovipakkausten erilliskeräys vai ei. Tutkimuksen mukaan pääkaupunkiseudun kotitalouksissa tuotettiin vuonna 2018 keskimäärin 157 kg sekajätettä vuodessa, joka on noin 20 kg vähemmän kuin vuonna 2015. Muovipakkausten määrä kotitalouksien sekajätteessä oli vähentynyt keskimäärin yli 30 %, joka on n. 8 kg asukasta kohti vuodessa. Samaan aikaan markkinoille on laskettu yhä enemmän muovipakkauksia. Pääkaupunkiseudun isoissa, yli 19 huoneiston kiinteistöissä, joissa on muovipakkausten erilliskeräys omalla kiinteistöllä, laitettiin muovipakkauksia sekajätteeseen keskimäärin 14 kg asukasta kohti vuodessa. Yli 19 huoneiston kiinteistöillä, joissa muovipakkausten erilliskeräystä ei ole järjestetty, laitettiin muovipakkauksia sekajätteeseen kesimäärin 17 kg asukasta kohti vuodessa. Muovipakkauskeräyksen aloittaminen on vähentänyt muovipakkauksten määrää pääkaupunkiseudun kotitalouksien sekajätteessä. Pääkaupunkiseudun asukkaat ovat ottaneet muovipakkauskeräyksen hyvin vastaan ja yhä useammat asukkaat lajittelevat muovipakkauksena. Muovipakkauksia lajitelevat myös sellaisissa kiinteistöissä asuvat, joilla ei ole muovipakkauskeräystä omalla kiinteistöllään.

Anthocyanins are pigment molecules responsible for the majority of flower colors existing in nature. Emerging from the flavonoid biosynthetic pathway, anthocyanin biosynthetic pathway branches into orange pelargonidin derivates, red cyanidin derivates and blue delphinidin derivates. Dihydroflavonol 4-reductase (DFR), a NADPH-dependent oxidoreductase, catalyzes the first anthocyanin specific step after the branching point for all three branches. In some cases, DFR exhibits substrate specificity leading to some flowering plant species’ inability to produce certain colors; like petunias lacking orange colors. Ornamental plant industry thrives on breeding of novel colors and color patterns, and thus understanding of the capabilities of anthocyanin biosynthesis is of key importance. The aim of this study is to gain insight into the amino acid residues causing substrate specificities in Petunia hybrida. The study focused on an amino acid region that has been previously identified as affecting substrate specificities in Gerbera hybrida. To examine the effects of three different mutations in this region, enzyme activity was examined both in vitro and in vivo. Experiments consisted of kinetic assays with protein extracts from infiltrated Nicotiana benthamiana and determination of anthocyanin content from stable transformations of Petunia hybrida. Anthocyanin content was determined from transformed petunia flowers with high performance liquid chromatography. Kinetic assays show distinct substrate specificity profiles for all three mutations, indicating a correlation between the studied residues and substrate specificity. The transformed petunias also exhibited altered anthocyanin content, with two of the three mutant transformants exhibiting increased pelargonidin production. The observed effects of these mutations support the previous results indicating that this region has a role in determining substrate specificities of DFR enzymes.

As biodiversity is declining globally, there is a crucial need to understand the connections between diversity and ecosystem functioning. Research has shown that diversity tends to lead to higher productivity, but our understanding of the underlying reasons is still limited. For example, biotic interactions with mycorrhizal fungi could cause these diversity effects in plant communities, but few studies have assessed the subject. In this thesis, I studied the impacts of arbuscular mycorrhizal symbiosis on diversity effects with three research questions. First of all, I aimed to determine whether mycorrhizal symbiosis affects the diversity–productivity relationship across plant communities. Secondly, I divided diversity effects into two parts: complementarity and selection effects. These effects can be determined statistically. Finally, I studied how different species within the community respond to diversity. To answer these questions, I conducted a greenhouse study with varying plant communities. I manipulated the plant species diversity and used a fungicide treatment to suppress mycorrhizal fungi. After the growing period, I measured the biomasses of the plants as an indicator of productivity. I tested the effectiveness and side effects of the fungicide by estimating mycorrhizal colonization rates in plant roots and by testing its effects on non-mycorrhizal plant species. The fungicide treatment did not affect diversity–productivity relationship nor diversity effects significantly. However, fungicide treatment failed to reduce the overall mycorrhizal colonization rate and had varying effects on different plant species. One of the plant species benefitted from species diversity whereas other species experienced either no effect or a negative effect of increased diversity. No specific trait explained the varying responses on diversity. More research is needed to understand plants’ complex responses to decreasing biodiversity and biotic interactions, as well as to clarify whether fungicide is a fitting method for mycorrhizal suppression studies.