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Oil spillages represent a serious environmental hazard for flora and fauna of marine and coastal ecosystems. Though marine oil spills have decreased since the 1970s, the increasing production of petroleum goods remains a potential source of pollution due to its use and transportation. When aquatic organisms, including fish, are exposed to toxic oil compounds, this can cause sublethal morphological changes and increase mortality. In this context, herring have been frequently studied, and results suggest that particularly herrings eggs and larvae are highly susceptible to oil toxicity. In this thesis, a Bayesian meta-analysis was conducted to investigate the effects of crude and fuel oil on the mortality of herring eggs from the genus Clupea. Observations from laboratory studies, collected during a literature review, served as input for the statistical analysis. To this end, Bayesian inference modeling was applied to generate posterior probability distributions for additional mortality caused by exposure to oil mixtures. Also, oil concentration, oil type, exposure time, and temperature were analyzed to study possible correlations with mortality impacts. The results of this study suggest that acute mortality of exposed herring eggs is similar to mortality observed for individuals exposed to only small concentrations or none at all. Of all evaluated oil types, medium grade crude oil caused the most significant change in instantaneous mortality with increasing oil concentration. Generally, distinct oil types had a greater influence on mortality outcomes than temperatures at the given concentrations. For the lowest temperatures, some correlations for increased mortality were found. Overall, the unexplained variability between the reviewed studies has a relatively small influence on mortality outcomes. In conclusion, the mortality of exposed herrings eggs is most likely delayed due to sublethal effects, rather than immediate, at the modeled concentrations. Altogether, uncertainty amongst the posterior probability distributions is high, indicating a wide possibility range for the monitored parameters' actual values. The reasons for elevated uncertainty likely stem from diverse experimental setups, biological differences between tested species, relatively small sample sizes, and model-related issues. Thus, future research could consider additional variables, information from observational studies and other fish species to reduce uncertainty in mortality outcomes.

In recent decades, ancient DNA recovered from old and degraded samples, such as bones and fossils, has presented novel prospects in the fields of genetics, archaeology and anthropology. In Finland, ancient DNA research is constrained by the poor preservation of bones: they are quickly degraded by acidic soils, limiting the age of DNA that can be recovered from physical remains. However, some soil components can bind DNA and thus protect the molecules from degradation. Ancient DNA from soils and sediments has previously been used to reconstruct paleoenvironments, to study ancient parasites and diet and to demonstrate the presence of a species at a given site, even when there are no visible fossils present. In this pilot study, I explored the potential of archaeological sediments as an alternative source of ancient human DNA. I collected sediment samples from five Finnish Neolithic Stone Age (6,000–4,000 years ago) settlement sites, located in woodland. In addition, I analysed a lakebed sample from a submerged Mesolithic (10,000–7,000 years ago) settlement site, and a soil sample from an Iron Age burial with bones present to compare DNA yields between the two materials. Soil samples were converted into Illumina sequencing libraries and enriched for human mtDNA. I analysed the sequencing data with a customised metagenomics-based bioinformatic analysis workflow. I also tested program performance with simulated data. The results suggested that human DNA preservation in Finnish archaeological sediments may be poor or very localised. I detected small amounts of human mtDNA in three Stone Age woodland settlement sites and a submerged Mesolithic settlement site. One Stone Age sample exhibited terminal damage patterns suggestive of DNA decay, but the time of deposition is difficult to estimate. Interestingly, no human DNA was recovered from the Iron Age burial soil, suggesting that body decomposition may not serve as a significant source of sedimentary ancient DNA. Additional complications may arise from the high inhibitor content of the soil and the abundance of microbial and other non-human DNA present in environmental samples. In the future, a more refined sampling approach, such as targeting microscopic bone fragments, could be a strategy worth trialling.

An increasing number of fisheries utilize rights-based management approaches for achieving economic, social and environmental sustainability. It is widely accepted that fisheries management is to a large extent about managing human behaviour, hence social acceptance is prerequisite for a successful management regime. Based on stakeholder interviews, this study analyses the opinions related to the recently implemented individual transferable quota (ITQ) system for the Finnish herring and sprat fisheries. Similarly, opinions were collected in 2007 by Kulmala et al. related to a possible implementation of ITQs, thus creating a unique opportunity to compile results from both a pre and post individual quota management implementation scenario. In 2007, it was suggested that fishers would largely support an ITQ system in Finland. Accordingly, this study implies that most of the Finnish stakeholders are content with the properties of the new system, however inequalities were perceived among fishers targeting fish for human consumption. In general, the system is expected to achieve its primary goal of improved economic efficiency within the fishery industry.

Lymphedema is a progressive disease, resulting from abnormalities of the lymphatic system. It is characterized by swelling of one or more parts of the body, due to impaired lymph transport. Lymphedema has no definitive treatment and it can have serious effects on the patients' quality of life. However, the recent knowledge expansion of the molecular mechanisms regulating lymphangiogenesis provides new possibilities for the treatment of lymphedema. One of these mechanisms is the angiopoietin-TIE system. It has been shown recently that ANG2 is essential for the formation of lymphatic vasculature. Mice ANG2-deletion caused widespread lymphatic dysfunction, resulting in subcutaneous edema and chylous ascites. Lymphatic development is also regulated by TIE1 receptor, as its deletion in mice resulted in malformed jugular lymph sacs and severe edema. In this study, a model of autocrine TIE receptor activation has been established in endothelial cells to investigate the effect of the WT-ANG2 and four ANG2 mutants (T299M, N304K, C435S and R492Q) in TIE receptor phosphorylation and lymphedema. The role of these variants in direct cell adhesion has also been investigated in vitro using HeLa and lymphatic endothelial cells. The findings revealed that WT-ANG2 and soluble ANG2 variants induced both TIE2 and TIE1 activation in endothelial cells. We also found that N304K, C435S and R492Q mutants are secretion-deficients and retain the co-expressed WT-ANG2 inside the cells, causing a dominant negative effect in both TIE2 and TIE1 receptor activation which is likely associated with the lymphedema in the patients where the mutants were identified.

Parvalbumin (PV) interneurons are GABAergic inhibitory neurons that shape neuronal network activity and plasticity. They are involved in both developmental and adult plasticity and have recently been divided into subpopulations that differ in birthdate, intrinsic properties and are involved in different types of learning; while late born PV neurons, expressing low levels of PV, are required for the acquisition of new information, early born PV neurons, expressing high levels of PV, are involved in the consolidation of the information. PV cells can be enwrapped with perineuronal nets (PNNs), an extracellular matrix structure that stabilizes synapses and indicates a mature state of the cell. The development of PNNs correlates with the closure of critical period of plasticity in development, and the enzymatic removal in adulthood can reopen those periods. Similarly, antidepressants like fluoxetine have been proven to reopen critical periods of plasticity in adulthood (iPlasticity) and decrease PNN structures in PV cells. However, whether the effect of fluoxetine is restricted to a subpopulation of PV interneurons is unknown. In addition, no previous studies have yet investigated the maturity state of the PV subpopulation by analyzing its PNN structures. In this thesis we aimed to elucidate differences in the maturity state of the subpopulations and the fluoxetine effect in those. To do that, we treated a cohort of adult mice with a chronic fluoxetine treatment previously reported to be capable of the reopening of critical periods. Following, we performed an immunohistochemistry analysis to detect PV and PNN levels in the CA3b hippocampal area. In addition, our mice line expressed TdTomato (TdT) in PV cells which allowed a more sensitive detection of PV neurons. After imaging the slices with a confocal microscope, we analyzed the PV and PNN intensity both by manual counting and with a semi-automatic macro script in ImageJ software that we developed and validated. The PV intensity of control mice was used to divide the cells in two groups; low PV and high PV expressing cells. PNNs in those subpopulations in both the control and fluoxetine treated group were analyzed and statistically compared. The low PV subpopulation showed a significantly low PNN intensity compared to the high PV subpopulation, indication a plastic or immature low PV subpopulation and a mature or consolidated high PV subpopulation. Interestingly, fluoxetine selectively decreased the PNN structures in the high PV subpopulation, by bringing the PNN intensity to comparable levels found in the low PV network. No effect of fluoxetine in the low PV network was detected. Fluoxetine induced a change towards a plastic state in the network believed to be involved in memory consolidation by decreasing its PNNs structures. This discovery gives new insights on the understanding of antidepressant plastic actions, suggesting that a chance for strong memories to change could be facilitated with the drug, and explain the antidepressant’s effects when combined with psychotherapy. However, supplementary experiments to compare and define PV subpopulations and a confirmation of the selective effect of fluoxetine are needed to confirm the preliminary hypothesis suggested by our data.

Caged photolysable compounds have served to be pivotal to neuroscientific investigations; allowing the cognizing of molecular kinetics and properties of neuronal micro-machinery such as neurotransmitter receptors. Precision in terms of temporal and spatial resolution of neurotransmitter release endowed by photolysis has multitudinal applicabilities in the realm of GABAA receptors (GABAARs), their neuronal niche and effects on neuronal and network activity. Caged compounds, in their caged form, may display certain unideal traits such as undesired interactions with the system and antagonistic activity on the target receptor. This study aims to reevaluate the GABAAR antagonistic actions of caged Rubi-GABA, which was found to antagonize these receptors at significantly lower concentrations than those reported in the literature. Furthermore, this study electrophysiologically characterizes the possible antagonistic properties of a novel quinoline-derived UV-photolysable caged GABA compound, 8 DMAQ GABA, whose activity, in its caged form appears to have a much more favorable antagonism profile compared to the widely used RuBi-GABA. To assess the antagonistic effects of these compounds on GABAAR-mediated miniature inhibitory postsynaptic currents (mIPSCs) patch-clamp recordings were carried out in the whole-cell voltage clamp configuration on cortical layer 2/3 cortical pyramidal neurons in acute neocortical slices prepared from 16-18 day-old rat rats. The results of this study indicate a revised antagonism profile for caged Rubi-GABA, with marked GABAAR toxicity in the low micromolar range. The study also scrutinizes the photo-kinetic properties of both caged GABA compounds and reveals that the rate of GABA release from 8-DMAQ is slower than from RuBi-GABA.

The human gut is inhabited by gut microbiota, a complex and diverse ecological community of trillions of microbes that affect both the normal human physiology and countless disease states and susceptibilities. Understanding the composition, functions and the causes and effects of changes in the microbiota is invaluable for understanding diseases that are connected to the microbiota and developing better treatments to the diseases. The gut microbiota varies between individuals and keeps changing over time. Behind the variability are e.g. the person’s age, genetics, diet, environment, and especially diseases and the use of antibiotics. When antibiotic use disrupts the gut microbiota, the changes can persist for years. Antibiotic resistance tends to increase after the use of antibiotics. Since antibiotic resistance in bacterial pathogens is considered a major health threat, the characterization of the human gut resistome (the antibiotic resistance genes (ARGs) found in the gut microbiota) is of great medical interest. Next-generation sequencing techniques have enabled studying also those microbe species that cannot be cultured at the moment. Metagenomics provides information on all genetic material collected from a given environment and enables searching for any sequences of interest within it, e.g. ARG sequences. The development of Parkinson’s disease (PD) is suspected to begin in the enteric nervous system and spread from there toward the central nervous system. The use of antibiotics could be linked to PD through their effects on gut microbiota, and since these effects are modified by the gut resistome, the aim of this study was to find gene sequences coding antibiotic resistance in human gut metagenomics data originating from stool samples of PD patients and healthy controls, and to find out potential differences in the occurrence of antibiotic resistance genes in the gut microbes of the two study groups. DeepARG was the chosen method for searching antibiotic resistance gene sequences in the metagenomics data. The statistical data analyses, including alpha diversity, multivariate analyses, and differential abundance analysis, were performed with the R statistical programming language in RStudio. DeepARG found 840 different ARGs in 192 samples. The ARGs belonged to 29 different ARG classes. The alpha diversity analysis showed a small estimated difference between PD and control groups indicating a possible slightly higher ARG diversity in the PD group. Multivariate analysis did not give any strong suggestions of definite biologically meaningful differences between the study groups. 16 ARGs were deemed differentially abundant in the study groups. BepE, cmeA, cmlv, dfrE, mefC, msrB, opcM, oprM and RbpA seemed to have increased abundance, and arnC, BN537_02049, dfrK, mgrA, murA, tet35 and tetT were suggested to have decreased abundance in PD patients compared to the healthy controls. These ARGs do not appear interconnected in any other way except for some sharing antibiotic types to which they offer resistance, and some having similar resistance mechanisms. In the light of an ongoing, unpublished epidemiological study of the connection between PD and the use of antibiotics it would seem that only three ARGs (msrB, mefC and dfrE) might be somehow relevant in PD development, but their effects, if any, are most likely minor. Eight ARG classes were shown to have differential abundance between PD patients and healthy controls. Bacitracin, fosfomycin and polymyxin classes showed decrease and chloramphenicol, fosmidomycin, puromycin, rifampin and sulfonamide classes showed increase in abundance in PD compared to controls. The change in the abundance of a certain ARG could reflect change in the abundance of the bacteria carrying that resistance gene. If so, the follow-up questions would be how much change in the abundance of bacteria is due to the use of certain antibiotics and how much is caused by environmental factors. It also remains to be studied whether specific antibiotics associated with the ARGs that in this study showed differential abundance in PD patients and healthy controls might have an actual role in PD development. The results of this thesis study are later to be combined with and further studied alongside information coming from ongoing studies on antibiotics use in general population and in PD patients. While this study did not concentrate its efforts into finding novel ARGs, the metagenomics dataset could also in the future be applied for that purpose.

Municipal environmental authorities are required to conduct environmental monitoring. Unmanned aerial vehicles, UAVs, may be helpful in environmental monitoring but their applicability as a tool for municipal environmental monitoring has not been studied. In this thesis it was studied, how municipalities have been utilizing UAVs. Additionally, UAVs applicability for environmental monitoring and inspection work was tested using a litter monitoring experiment as an example. In the first part of the study, a questionnaire was sent to municipal environmental authorities in Finland, to municipalities in Sweden and to those participating in Eurocities WG Waste group (n = 512), covering the used applications, their utilization frequencies and successfulness, reasons for failures and future plans. The results were analyzed using descriptive statistics. In the second part of the study, a UAV was utilized in a litter monitoring experiment on four sites in Helsinki. Litter by category and leaves were counted based on visual observations from UAV imagery. The accuracy of UAV imagery detection was assessed by comparing its and ground assessment (GA) results. On one site, a control group also carried out UAV imagery detections in order to assess the magnitude of bias or offset occurring when both the GA and the litter detection from UAV imagery are conducted by a single individual. The Wilcoxon signed rank and Cronbach’s α reliability tests were used for statistical analysis of the results. Response rate of the questionnaire was low, 3.7% (n = 19). The pool of used applications was extensive and covered a variety of monitoring and inspecting targets with emphasis on the presumably manually piloted applications. Utilization was very successful. The most important reasons for failures were poor weather followed by lack of information and expertise. UAVs were included in the future plans of most participants for municipal environmental monitoring purposes. The UAV imagery detection accuracies of litter and leaves compared to the GA results were high, 90.5% for litter and 87.5% for litter and leaves, and no statistically significant differences existed between the assessment results. Especially leaves proved challenging to detect from UAV imagery. The control group’s detection accuracies were 67.9% without and 49.0% with leaves, and with leaves the results differed with statistical significance (p = 0.028). The internal reliability of the control group was relatively high, α = 0.776 without and α = 0.805 with leaves. UAVs are deemed sufficiently accurate and versatile as monitoring and inspecting tools for municipal environmental authorities. They have the capability to complement ground assessments or, with certain prerequisites, even function as an independent monitoring method. Further application and detection method development and research on municipal UAV utilization are needed.

Monen eri eläinryhmän edustajat käyttävät sosiaalista informaatiota sekä lajinsisäisesti, että lajienvälisesti erilaisten kelpoisuuteen vaikuttavien päätösten tekemisessä. Sosiaalinen informaatio voidaan jakaa tahallisiin ja tahattomiin signaaleihin ja informaation havainnoija voi käyttää tahattomia signaaleja hyväkseen johtaen siihen, että signaalin tuottaja kärsii huonommasta kelpoisuudesta. Tästä johtuvat valintapaineet voivat luoda informaation peittämisstrategioita signaalin tuottajassa. Tämä voi puolestaan johtaa osapuolten väliseen adaptaatioiden sykliin, jota kutsutaan myös koevolutiiviseksi kilpavarusteluksi. Pesäloiset ja niiden isäntälajit ovat klassinen esimerkki tällaisesta vuorovaikutussuhteesta. Leppälintu (Phoenicurus phoenicurus) on ainoa käen (Cuculus canorus) isäntälaji, joka pesii pelkästään koloissa. Kolopesintä tekee leppälinnusta erityisen isännän, eikä sen puolustautumiskäyttäytymistä ole laajalti tutkittu. Tutkimukseni päähypoteesi on, että leppälinnut piilottavat sosiaalista informaatiota käeltä puolustamalla niiltä pesäänsä vähemmän munintavaiheessa verrattuna haudontavaiheeseen. Aiemmissa tutkimuksissa näitä kahta vaihetta ei olla juurikaan vertailtu, vaikka käki loisii pesän pelkästään isännän munintavaiheessa. Testasin päähypoteesiani kenttäkokeilla, joissa ensin vertailin sitä, miten usein leppälinnut ovat läsnä pesillään muninnan ja haudonnan aikana sekä sitä, miten ne puolustavat molemmissa vaiheissa eri uhkia vastaan: pesäloinen, saalistaja ja kontrolli. Leppälinnut olivat enemmän pesillään haudonnan aikana ja tämä johtuu luultavasti siitä, että silloin linnut ovat panostaneet enemmän pesintäyritykseensä ja siitä, että naaraan täytyy pysyä pesällä pidempiä aikoja. Kaiken kaikkiaan, linnut puolustivat pesiään enemmän haudontavaiheessa, mutta niiden reaktio käkeä vastaan oli alhainen molemmissa vaiheissa. Jos siis leppälinnut peittävät informaatiota käiltä, ne eivät muuta tätä käyttäytymistä muninnan ja haudonnan välillä. Lintujen varoittelu lisääntyi saalistajan läsnä ollessa, mutta muu puolustautuminen ei vaihdellut uhkien mukaan. Tulokseni osoittavat, että saalistus saattaa olla pesäloisintaa suurempi uhka leppälinnuille tai että leppälinnut eivät tunnista käkeä uhkaksi. Kolopesintä vaikuttaa olevan leppälinnun paras puolustus käkeä vastaan, mutta lisää tutkimusta tarvitaan näiden kahden välisen dynamiikan tarkastelemiseksi.

Kiinnostus käyttää psykedeelejä, kuten lysergihapon dietyyliamidia (LSD) ja psilosybiiniä, erinäisten psykiatristen sairauksien hoidossa ei ole jättänyt huomiotta päihteiden väärinkäyttöä. Tutkimukset ovat osoittaneet alustavia positiivisia vaikutuksia LSD:n käyttämisessä erinäisten addiktioiden, kuten kokaiini-, nikotiini- ja alkoholiriippuvuuksien hoidossa. LSD:n on raportoitu auttaneen joitain alkoholismista kärsiviä pysymään raittiina jopa 6-12 kuukautta yksittäisen LSD annoksen jälkeen. Valitettavasti näitä tuloksia on hankala tulkita, ja vaikutusten taustalla olevat mekanismit tunnetaan huonosti. Tutkimme hiirimallimme avulla, kuinka yksittäinen LSD annos vaikuttaa ahmimiskäyttäytymiseen. Käytimme sukroosiliuosta ahmivaa eläinmallia palkkionottamiskäyttäytymisen mallintamiseen, mikä on yksi addiktioihin liittyvän käyttäytymisen tunnusmerkeistä. Tutkimuksemme tavoitteena oli selvittää vaikuttaako LSD palkkionottamiskäyttäytymiseen, ja siten mahdollisesti aivojen palkkiojärjestelmään. LSD -annostelu (0,05 ja 0,1 mg/kg, i.p.) vähensi akuutisti sukroosiliuoksen ahmimiskäyttäytymistä, mutta vaikutus loppui viikon kuluessa. Tästä havaitusta akuutista vaikutuksesta huolimatta erot ryhmien välillä eivät olleet tilastollisesti merkittäviä. Täten oletettiin, että nettovaikutukset aivojen palkkiojärjestelmään ovat epätodennäköisiä. Kuitenkin pelkän i.p. injektion (10 ml/kg) havaittiin vaikuttavan veden juomiseen. Havaitsimme merkittävän piikin veden juonnissa injektointipäivänä, mikä palautui normaalitasolle jo seuraavaan päivään mennessä. Nämä tulokset johtivat jatkotutkimukseemme, jossa osoitettiin injektion aiheuttavan piikin vedenjuontiin riippumatta siitä, injektoidaanko saliinia vai LSD:tä. Tätä vaikutusta ei enää havaittu, mikäli injektioita annettiin perättäisinä päivinä, mutta jopa yhden tai kahden päivän väli injektioiden välillä riitti palauttamaan injektion aiheuttaman piikin vedenjuontiin. Koska onnistuimme poistamaan vedenjuontiin aiheutuneen vaikutuksen toistetuilla saliini-injektioilla, eikä vaikutus palautunut injektoitaessa LSD:tä, voimme todeta, että vaikutus liittyi injektiotoimenpiteeseen. Keskeisin havaintomme tässä tutkimuksessa oli, ettei LSD:llä ole merkittävää akuuttia vaikutusta sukroosiliuoksen ahmimiskäyttäytymiseen tässä hiirimallissa.