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(2013)Adaptive radiation is an important mechanism of evolution, which can lead to emergence of sympatric species or morphotypes. Among other biological interactions, parasitic pressure can have significant evolutionary implications for host populations by reducing the fitness of the host individuals. Parasite community structure of fishes is typically strongly dependent on both host ecology (e.g. habitat and feeding behaviour) and environmental factors (e.g. water quality and temperature). However, the relative importance of these factors for parasite-mediated speciation is not known. Also, host gender-specific differences in parasite communities can have an effect on the differentiation of host morphs. In this Master's thesis, I focused on differences in parasite communities of sympatric morphs of three-spine stickleback (Gasterosteus aculeatus) in two large Icelandic lakes, Thingvallavatn and Mývatn. In these lakes, the habitats of sympatric mud and lava morphs are the same (soft/hard bottom), but the habitat water temperatures are opposite between the lakes. In this unique system, it is thus possible to compare between the effects of host ecology and water temperature on parasite community structure and strength of parasite-mediated selection. Additionally, I studied the effect of host sex on the parasitic pressure. There is also a third stickleback morph, Nitella morph, inhabiting the cold limnetic habitats in Lake Thingvallavatn. I sampled the stickleback morphs from both lakes and identified their parasite species. I discovered a total of five parasite genera: trematodes Apatemon and Diplostomum, and cestodes Diphyllobothrium, Proteocephalus and Schistocephalus. Most of the observed parasites have negative effects on health and fitness of the host. I found more parasites in sticklebacks living in higher temperature in both lakes regardless of the morph. When comparing the cold water morphs in Thingvallavatn, parasite abundance was higher in the limnetic Nitella morph than in the shallow water lava morph. Fish gender had an effect on parasitism only in Thingvallavatn as males of both lava and Nitella morphs were more heavily infected with cestodes. Similarities in parasite communities with water temperature indicate that water temperature mainly determines parasite infections in this system instead of host ecology. As similar fish morphotypes exist in different lakes under opposite parasitic pressure, parasitism has unlikely initiated host differentiation, but differences in infection probably have emerged secondary to the ecological specialization of the morphs to different habitats. These results are among the first to tackle the key question in parasite-mediated divergent selection: at which point of the speciation process parasite communities become differentiated and thus can have an effect on speciation. However, the comparison between the cold water morphs (lava and Nitella) indicates that although water temperature seems to be the main factor controlling infections in this system, its effect may still be over ridden by host ecology. Sex-depended differences in parasitic pressure, on the other hand, are likely to reflect specific characteristics of each fish population and lake. These results suggest complex interactions between host ecology and abiotic environment, such as water temperature, in determining the parasite community structure. Hence both factors have to take into consideration when studying the role of parasites in speciation processes. In future, it is necessary to pinpoint the stage of the host speciation process when parasite infections become differentiated in replicated systems to gain comprehensive understanding of the role of parasites in adaptive radiations.
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(2015)This interdisciplinary study seeks to raise awareness of and generate interest in projects that combine science and art. A number of such projects are discussed and analyzed with the help of the concept 'Ecovention'. The concept is operationalized to include works of art that ecologically restore, reclaim, and remediate damaged ecosystems by physical actions and inventions. They transform the ecosystem and often slowly disappear into the environment, contributing to the overall wellbeing of the ecosystem. These works of art are long-lasting and site-specific. They are built outdoors by using material that is already available in the ecosystem or by bringing in environmental-friendly material into the ecosystem. The central research question for the study is as follows: How significantly does environmental art affect the local ecosystem when the starting point is ecological restoration? This is a qualitative study. The data for the study consist of interviews with experts together with analyses of the historical, cultural, and ecological background material for two Finnish environmental artworks. The two artworks are Agnes Denes's Puuvuori (Tree Mountain - A Living Time Capsule, 1996) and Jackie Brookner's Veden taika (The Magic of Water, 2007- 2010). These works of art were chosen because of the availability of historical and natural scientific research data about how they were planned and how they were constructed. The availability of this kind of data related to environmental art is rare in Finland. The Magic of Water consists of three floating islands in Salo. They are situated in a lagoon that was formerly used as a clarification pool at the Salo Municipal Sewage Treatment Facility. The artwork has succeeded in supplying a peaceful nesting habitat for the birdlife in the area. It has been shown that a colony of black-headed gulls (Larus ridibundus) is a new species nesting in the islands. The Magic of Water did not provide a significant improvement of the water quality by phytoremediation since the islands are relatively small in relation to the area of the lagoon. Tree Mountain - A Living Time Capsule is to be found in Pinsiönkangas, at the most important groundwater area in Ylöjärvi. The artwork reclaims a former gravel pit. Tree Mountain is a 28 meter tall hill in an area of elliptical shape that spans nine hectares. 10,600 pine tree saplings (Pinus sylvestris) and about 40,000 cubic meters of soil from the area was used to build the artwork. Tree Mountain is nowadays owned by the town of Ylöjärvi and Pinsiönkangas is principally a conservation area. The Tree Mountain - A Living Time Capsule is argued to fit well in the regionally precious ridgescenary since the work of art has enough of biological values. Most likely the building of the artwork has had a preventive effect on possible ecological harm and it has made the community take responsibility for taking care of the reclaimed environment in the long term. In the face of high-quality ecological restoration plans it is important to approach the restoration of ecosystems from a holistic perspective. The artist s vision of how an ecosystem can be restored adds a surplus value to ecological restoration work since also the aesthetic and ideological dimensions are reconstructed. The probable positive view of the community towards the restored ecosystem can promote not only the attendance by the community to that particular area in the future, but it can also promote the attendance of a community to other areas as well.
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(2012)Many pathogens are able to survive and reproduce in the environment outside of host for instance by saprotrophic lifestyle. These kinds of pathogens are called opportunistic as compared to obligatory pathogens that cannot interact or reproduce in the environment outside of host. Opportunistic pathogens are subject to strong selection forces in the environment outside of host for instance while they compete for resources they share with other microbes. Ecological interactions in the environment outside of host can therefore influence on the disease dynamics and evolution of virulence of an opportunistic pathogen. No proper theoretical model that would acknowledge opportunistic reproduction and ecological interactions in the environment out side of host has been developed before. Yet it is essential to develop this kind of theoretical model so that the development and dynamics of opportunistic diseases could be predicted and prevented. In this work, an opportunistic disease model was developed that considers both the opportunistic reproduction and the influence of a superior competitor as compared to pathogenic strain on pathogen growth in the environment outside of host. Differential equations in the model represent the density changes in time in the populations of susceptible and infected host, pathogen and rival strain outside host that is not pathogenic. Evolution of virulence of the new opportunistic pathogen meaning the ability to grow from low density in presence of superior competing strain was modeled in differing circumstances. Opportunistic disease dynamics was modeled in differing circumstances, when non-pathogenic competing strain was either present or absent. Equilibrium equations were solvable to a system, where non-pathogenic competing strain was absent, but to a system where non-pathogenic competing strain was present. Analyses of the model were performed with Math Works MATLAB – program. Reproducing inside host gives an opportunity for new opportunistic pathogen to increase in density under circumstances where competition is moderate enough so that the reproduction in the environment outside host may compensate opportunistic pathogen's weaker ability to compete. Reproduction and competition in the environment outside host produce disease dynamics that differ from more traditional SI-models. Density dependence of the reproduction in the environment outside host stabilizes host-parasite system in the absence of competition in the environment outside host. Instead, in the presence of competition the competitive advantage of the non-pathogen strain destabilizes disease dynamics and prevents extinction of the susceptible host. Reproduction in the environment outside host also enables opportunistic pathogen to remain in the environment in the absence of susceptible hosts and functions thus as a potential mechanism for disease out breaks when circumstances change. However, increasing competition in the environment outside host at the expense of opportunistic pathogen may potentially prevent epidemics. Among other things, the model could be applied to biological control with the intension of removing an opportunistic pathogen naturally by weakening its survival in the environment out side of host in a competiotion situation. This kind of biological control could for example be possible in the case of saprotrophic Flavobacterium columnare –fish pathogen that is found in fish farms.
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(2022)Permafrost peatlands have a significant role in the global carbon cycle, as they store ca. 185 Pg of carbon. Because of the slow decomposition of organic matter, they have sequestered carbon dioxide from the atmosphere and cooled the climate for thousands of years. However, in anaerobic decomposition also methane – a strong greenhouse gas – is produced. Climate change results in changes in permafrost peatland habitats; distribution and proportional share and these changes also affect the CO2 and CH4 fluxes. In this master’s thesis I compare the net ecosystem exchange and pore water methane concentrations in different microhabitats in the Stordalen palsa mire in Abisko, Sweden. In addition, I review the reported climate change-driven habitat changes in the area and its effects on the CO2 and CH4 fluxes. My results suggest that Sphagnum sp. and Sphagnum fuscum -microhabitats were net sinks of CO2 whereas lichen-, shrub- and Eriophorum-microhabitats were net sources. These results were best explained by the proportional coverage of green vegetation, which was highest in both Sphagnum-microhabitats. No discernible differences were found between pore water methane concentrations in different habitats. Permafrost thawing has increased the occurrence of wet habitats in Stordalen. These habitat changes have increased carbon sequestration in the area but at the same time methane emissions have also increased. Because of this, the radiative forcing of the peatland has changed from negative to positive and the on-going habitat changes will likely continue in future. On a longer timespan though, the radiative forcing will likely switch back to negative as carbon sequestration increases and the effects of the methane emissions decrease.
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(2020)Tutkielman tarkoituksena oli selvittää ja verrata keskenään kahden luontaisesti kalattoman järven eläinplanktonyhteisöjen rakennetta sekä kalaistutusten vaikutuksia siihen. Tarkoituksena oli myös selvittää äyriäiseläinplanktonin vasteita saalistukseen erilaisen predaatiopaineen vallitessa. Luontaisesti kalattomissa järvissä eliöyhteisö on muovautunut hyvin erilaiseksi visuaalisesti saalistavien kalojen puuttuessa. Näissä järvissä pääpredaattorina toimivat usein selkärangattomat pedot, joiden saalistustekniikka eroaa selvästi kalojen saalistuksesta, ja ne ovat usein kokorajoitteisia ravinnon käytön suhteen. Kalojen visuaalinen saalistus kohdistuu kooltaan suurimpiin ja näkyvimpiin äyriäiseläinplanktoneihin ja ne voivat näin tehokkaasti vaikuttaa eläinplanktonin kokorakenteeseen. Luontaisesti kalattomiin järviin tehdyillä kalaistutuksilla voi olla merkittäviä vaikutuksia koko järven eliöyhteisöön. Oletuksena oli, että äyriäiseläinplankton olisi kooltaan suurempaa kalattomassa järvessä verrattuna istutettuun järveen. Oletimme pienikokoisen Bosmina spp. -vesikirpun suojautuvan selkärangattomien petojen predaatiota vastaan erilaisten korostuneiden morfologisten piirteiden avulla. Myös äyriäiseläinplanktonin vertikaalisen sijainnin oletettiin eroavan järvien välillä. Kuutsjärvi ja Tippakuru sijaitsevat Värriön luonnonpuiston alueella Itä-Lapissa. Molemmat tutkimusjärvet ovat luontaisesti kalattomia latvajärviä, mutta Kuutsjärveen on istutettu taimenta 1980-luvulla ja se muodosti järveen pysyvän taimenkannan. Eläinplanktonnäytteet otettiin limnos -putkinäytteenottimella järven syvimmästä kohdasta koko vesipatsaan syvyydeltä metrin välein kesällä 2010, kolmena eri näytteenottokertana. Näytteet mikroskopoitiin ja niistä määritettiin lajit/suvut mahdollisimman tarkasti ja äyriäiseläinplanktonin koko mitattiin. Näytteistä määritettiin eläinplanktonin tiheydet, äyriäiseläinplanktonin biomassat, keskikoot ja kokojakaumat. Lisäksi mitattiin pienikokoisen Bosmina spp. -vesikirpun ulokkeiden (mucro, antennula) pituudet predaatiopaineen vaikutusten arvioimiseksi. Äyriäiseläinplanktonin vertikaalinen sijainti vesipatsaassa määritettiin. Selvimmin pelagiaalin eläinplanktonyhteisöt erosivat toisistaan kokonaistiheyksien osalta, minkä aiheutti rataseläinten voimakas lisääntyminen kalattomassa Tippakurussa kesän aikana. Eläinplanktonlajisto oli järvissä kuitenkin hyvin samanlainen ja lajirunsaus vain hieman suurempi kalattomassa Tippakurussa. Äyriäiseläinplanktonin biomassat vaihtelivat kuukausien välillä, mutta eivät eronneet merkittävästi järvien välillä. Molemmissa järvissä hallitsevina äyriäiseläinplanktoneina esiintyivät hankajalkaiset ja vesikirppuja esiintyi selkeästi vähemmän. Äyriäiseläinplanktonin keskikoot erosivat joiltain osin järvien välillä ja olivat pääosin suuremmat kalattomassa Tippakurussa. Kalattomille järville tyypillistä hyvin suurikokoista eläinplanktonia ei Tippakurussa kuitenkaan esiintynyt ja erot jäivät tästä syystä oletettua pienemmiksi. Pienikokoisen Bosmina spp. -vesikirpun mucrojen pituuksissa havaittiin kuitenkin selkeä ero. Mucrot olivat kooltaan selvästi suuremmat kalattomassa Tippakurussa koko kesän ajan ja tätä ollaankin pidetty yhtenä luotettavimpana Bosmina spp. -vesikirppujen vasteena selkärangattomien petojen saalistukseen. Äyriäiseläinplanktonin sijainnissa havaittiin eroja lähinnä hankajalkaisten ja vesikirppujen välillä, mutta järvien välillä erot olivat vähäisiä, joitain yksittäisiä tapauksia lukuun ottamatta. Erilaisesta predaatiopaineesta huolimatta järvien eläinplanktonlajisto erosi vain vähän järvien välillä ja erot olivat joiltain osin jopa päinvastaisia oletettuun nähden. Kuutsjärven eläinplanktonlajisto muistutti monelta osin muiden istutettujen järvien lajistoa, koostuen lähinnä pienikokoisesta äyriäiseläinplanktonista ja rataseläimistä. Järvessä esiintyvä taimen ei ole tehokas planktivori, joten se on todennäköisesti vaikuttanut Kuutsjärven eläinplanktonlajistoon lähinnä trofiatasojen välisten vuorovaikutusten kautta, hävittämällä selkärangattomat pedot pelagiaalista. Tippakurussa sen sijaan havaittiin kalattomille järville poikkeuksellisen runsaasti rataseläimiä ja äyriäiseläinplankton oli kooltaan verrattaen pientä. Myös äyriäiseläinplanktonin sijainti oli monilta osin poikkeava muihin tutkimuksiin nähden. Tippakurun pelagiaalissa, poikkeuksellisesti myös päiväsaikaan esiintyneet selkärangattomat pedot G.lacustris ja C. flavicans ovat tehokkaalla, myös suuriin eläinplanktereihin kohdistuneella predaatiollaan todennäköisesti muovanneet Tippakurun eläinplanktonyhteisöstä ja sen vasteista hyvin omaleimaisen sekä poikkeavan muihin kalattomiin järviin nähden. Voimakkaammasta selkärangattomien petojen predaatiosta Tippakurussa kuitenkin kertovat Bosmina spp. -vesikirpun suuremmat mucrot verrattuna Kuutsjärveen, jossa istutettu taimen on hävittänyt selkärangattomat pedot pelagiaalista.
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(2022)Eläinten tunnemaailma on meille melko vieras. Sen takia on tärkeää tutkia, millaiset asiat vaikuttavat siihen, miten tulkitsemme niiden tunteita. Tunteiden tulkintaan voivat vaikuttaa tulkitsijan omat kokemukset. Tämän tutkielman tarkoituksena on tutkia sitä, mitkä asiat vaikuttavat siihen, kuinka hyvin eläintarhakävijät tunnistavat villieläinten tunteita. Erityisesti keskityn siihen, miten vastaajan sukupuoli, ikä, kasvuympäristö ja lapsuuden ja aikuisuuden aikaiset eläinkokemukset vaikuttavat eläintarhakävijöiden kykyyn tunnistaa eläinten tunteita. Tutkimus tehtiin kyselytutkimuksena Korkeasaaren eläintarhassa kesällä 2021. Osallistujille näytettiin videolta eläin ja heidän tuli kertoa, onko eläimen tunnetila neutraali, myönteinen vai kielteinen ja onko se rauhallinen vai kiihtynyt. Tutkimuksessa tutkittiin tiikereiden, berberiapinoiden ja markhorvuohien tunnetilan tunnistamista. Osallistujista kerättiin taustatietoja, kuten ikä ja sukupuoli. Tulosteni perusteella eläinlajilla on vaikutusta tunnetilan tunnistamiseen. Tiikerin myönteisyys tai kielteisyys osattiin arvioida huonommin kuin berberiapinan. Myös vastaajan ikä vaikuttaa tunteiden tunnistukseen. Vanhemmat tunnistivat myönteisyyden tai kielteisyyden nuorempia ihmisiä heikommin. Sukupuoli vaikuttaa yhdessä iän kanssa kiihtyneisyyden tunnistamiseen. Kiihtyneisyyden tunnistivat paremmin 18–30-vuotiaat naiset kuin 61–75-vuotiaat naiset, mutta muiden ryhmien välillä ei havaittu merkitseviä eroja. Kiihtyneisyys tunnistettiin myös paremmin, jos eläimet ovat olleet osana vastaajan elämää vain lapsuudessa sen sijaan, että ne olisivat olleet aina osana elämää. Tulosten perusteella voidaan päätellä, että ihmiset tunnistavat eri eläinten tunteet eri tavalla ja ihmismäisempien eläinten tunteet ovat muita helpommin tunnistettavissa. Iällä ja sukupuolella voi olla vaikutusta ihmisten kykyyn tunnistaa eläinten tunteita. Myös eläinkokemus vaikuttaa ihmisten kykyyn tunnistaa tunteita ja kokemus ei ole sama kuin tiedon omaksuminen. Tuloksiani voidaan hyödyntää esimerkiksi ympäristökasvatuksessa.
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(2023)Research into animal emotions is important for improving animal welfare and understanding behavior. Emotional research also provides a better overview of ecology and helps from the point of view of protection. According to the consensus, animals feel different emotions and express their feelings in many ways. Emotional expression is also an important part of communication between animals. In my research, I wanted to study zoo visitors’ ability to interpret animals’ emotions. The study was conducted in Korkeasaari as a survey, where respondents were asked to rate animals’ valence and arousal based on short video clips. According to several theories, valence and arousal are two important dimensions of emotion. Interpretation is based on movements, expressions, and gestures of one animal or several animals. In my research, I used videos of Barbary macaque, Siberian tiger, and Markhor expressing different emotions. The aim of this study was to explore if there are differences in participants ratings between the species. In addition, I explored whether a specific emotion is interpreted better than others. I expected that, based on an evolutionary distance, the emotions of the Barbary macaque would be interpreted best despite the emotion. Secondly, I expected the best identification of negative Valence and high arousal, which would be important for evolution and survival. I found that the valence of the barbary macaque was interpreted best, but the arousal of the markhor was interpreted as well as the Barbary macaques. Different emotions were interpreted differently in each specie. The interpretation of emotions is also influenced by the participant’s demographic factors such as age and gender. Differences in ratings between the species may also be explained by species-specific factors such as the extent of the emotional scale to be expressed or need to express emotions. Together with other similar studies, the aim of this study is to improve animal welfare and to increase interest and knowledge of animal emotions.
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(2023)Supplementary bird feeding is a popular pastime, as well as one of the most important types of human–wildlife interaction, in Western countries. Bird-feeder sites are visited by birds, mammals, as well as other animals; some of these species are wanted visitors, some unwanted. Supplementary food at feeding sites offers visitors benefits, at least during winter. However, effects at the species, population and community level can be complex, and none of these levels necessarily benefit automatically from supplementary feeding. On the other hand, bird feeding generally increases human wellbeing. Animal attitudes affect the way we think about non-human animals. It has been discovered that how we view animals visiting feeding sites affects the ways in which people feasibly change the supplementary feeding they provide. Research on the subject has mostly been Anglo-American in context to date. Animal attitudes also affect official rules and regulations that govern the supplementary feeding or control measures of wildlife, for example. In this thesis, I have investigated the responses from a 2021 survey by the Finnish Museum of Natural History (Luomus) and BirdLife Finland. The survey was concerned with supplementary bird feeding and recent changes thereof. The survey got over 14,000 responses, over 9,000 of which included answers to open-ended questions. I sifted through the open-ended responses to find out which animal species and other organisms affect supplementary bird feeding provided by the respondents, and why. I utilised both quantitative and qualitative research methods to uncover such organisms and their effects. I used qualitative content analysis as my main method. I discovered that there are many types of primarily animal-/organism-related reasons behind changes in bird-feeding behaviour. I categorised these 28 reasons under seven subcategories within three main categories. Many of the reasons can have both negative (stop/decrease/shorten) and positive (start/increase/extend) effects on supplementary feeding. A discernible portion of the reasons are propped by one animal attitude or another. The category-based assortment of reasons acts as the main finding of this study, and it reflects the complexity of animal attitudes. I have additionally listed all taxons (species/groups of organisms) found in the survey responses along with their effects on supplementary feeding. I have produced novel information on which animal-related factors affect supplementary bird feeding in Finland, and why. Were we to better understand the inherent complexity of animal attitudes, authorities’ facts-based decision-making and a favourable general attitude towards endangered-species conservation could be enhanced. Zoonosis control could also gain new perspectives from novel information.
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Electrophysiological screen reveals 8 genes in zebrafish model of catastrophic childhood epilepsies (2022)Catastrophic childhood epilepsies are characterized by persistent seizures and are frequently associated with cognitive and developmental impairments. Many, approximately 30%, of these epilepsies are rare genetic disorders that do not have effective therapeutic options. The bench to drug process is lengthy and expensive, and thus it is critical to find more affordable drug screening options. Zebrafish are an ideal model organism for screening studies as they share considerable (70%) genetic similarities with humans and are cheap to maintain with efficient breeding capabilities. In the present study, 37 zebrafish lines were screened for epileptic brain activity to identify high priority genes for future pharmacology studies. Each zebrafish line, generated by CRISPR-Cas9 represents a single gene loss of function mutation associated with 3 epilepsy based on genome wide association studies. Larval zebrafish were screened for spontaneous seizure activity using electrophysiological assays. The following 8 genes were significantly associated with spontaneous seizure activity in zebrafish: EEF1A, ARX, GRIN1, GABRB3, PNPO, STRADA, SCN1A, and STXBP1. There is now an open-source database for all 37 zebrafish lines, which contains sequencing information, survival curves, behavioral profiles, and electrophysiological data. The findings reveal novel target genes for future drug development and discovery. Future work is needed to explore whether zebrafish also model co-morbidities commonly seen in human patients with epilepsy.
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(2017)Lämpenevä ilmasto muuttaa boreaalisten metsien lajikoostumusta. Uudet lajit levittäytyvät yhä pohjoisemmaksi lämpenemisen siirtäessä kullekin lajille luontaisia elinympäristöjä. Lisäksi perustuotannon, karikkeen hajoamisen ja ravinteiden saatavuuden on ennustettu muuttuvan, mikä asettaa uusia sopeutumistarpeita kasvien typpitaloudelle. Erityisesti pitkäikäiset puut kohtaavat merkittävän haasteen suotuisten elinympäristöjen siirtyessä nopeammin kuin puut kykenevät itse leviämään uusiin kasvuympäristöihin. Tässä pro gradu- työssä tarkastelen elinympäristön muutoksen vaikutuksia neljän rauduskoivupopulaation (Betula pendula) puiden elinvoimaisuutta ilmentäviin ominaisuuksiin sekä niiden tuottaman karikkeen laatuun ja hajoamiseen. Hyödynsin tutkimuksessani olemassa olevaa koeasetelmaa, jossa pohjois-eteläsuuntaista gradienttia edustavista populaatioista (alkuperistä) kloonattuja rauduskoivun taimia on istutettu yhteisille "common garden" -kasvupaikoille Tuusulaan, Joensuuhun ja Kolariin. Erityisesti etelään päin siirron on tarkoitus simuloida ilmaston lämpenemistä. Tutkimusaineistoni koostuu 233 taimesta, joista määritin pituuskasvun, lehtien hiili- (C), typpi- (N) ja vesipitoisuuden sekä typen takaisinottotehokkuuden, lehtialaindeksin ja herbivorivioituksen. Lisäksi määritin maatuvan lehtikarikkeen massahäviön ja lehtikarikkeesta vapautuvan typen määrän 3 kk kestäneessä maatumiskokeessa. Aineiston keräsin puiden neljäntenä kasvukautena aikavälillä 27.6.2014 – 6.3.2015. Tulosten tilastolliseen analysoimiseen käytin varianssi- ja korrelaatioanalyysejä. Vihreiden lehtien N-pitoisuus (%) pieneni lineaarisesti pohjois-eteläsuuntaisesti, kun taas typen takaisinottotehokkuus heikkeni ja muodostuvan lehtikarikkeen N % kasvoi, kun populaatioita siirrettiin pohjoiseen tai etelään alkuperäiseltä kasvupaikaltaan. Siirto vähensi myös pituuskasvua ja lehtien vesipitoisuutta. Herbivorivioitus ja lehtialaindeksi eivät reagoineet siirtoon. Vihreiden lehtien N % korreloi positiivisesti typen takaisinottotehokkuuden kanssa. Mitä suurempi takaisinottotehokkuus, sitä pienempi oli typpipitoisuus lehtikarikkeessa. Maatuvan karikkeen massahäviö kasvoi, mitä suurempi oli maatuvan karikkeen N-pitoisuus. Erityisesti Joensuun ja Tuusulan kasvupaikoilta kerätyn karikkeen massahäviö oli sitä suurempaa, mitä pohjoisemmasta alkuperästä oli kyse. Typpeä ei vapautunut maatumiskokeen aikana, eikä typen vapautuminen korreloinut lehdistä mitattujen ominaisuuksien kanssa. Tulokseni osoittavat, että rauduskoivun pituuskasvu, lehtien vesipitoisuus ja sisäinen typpitalous ovat parhaimmillaan alkuperäisellä kasvupaikalla, ts. populaatiot ovat paikallisesti sopeutuneita. Muutokset typen takaisinottotehokkuudessa näyttävät liittyvän rauduskoivun kasvuun, joka heikkeni elinympäristön muuttuessa. Populaatioiden pohjois-etelä-siirto heikensi typen takaisinottotehokkuutta ja lisäsi maatuvan karikkeen massahäviötä. Tulokseni osoittavat, että tulevaisuuden muuttuvat ilmasto- ja ympäristöolosuhteet voivat heikentää puiden elinvoimaisuutta pohjoisissa ekosysteemeissä, mutta toisaalta samanaikaisesti kiihdyttää karikkeen maatumista parantamalla muodostuvan kasvikarikkeen laatua.
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(2022)Mercury is a toxic heavy metal that ends up in aquatic ecosystems both as atmospheric deposition as well as from the catchment area surrounding the water body. Under the right circumstances, inorganic mercury can be methylated into methylmercury, which accumulates in organisms and food webs and is harmful to humans and animals. Humans are exposed to methylmercury mainly through consumed fish as almost all the total mercury content in fish muscle consist of methylmercury. Mercury content of fish is affected by numerous different factors, such as the food consumed by the fish, the characteristics of the fish species and fish individual, level of lake eutrophication, mercury concentration in water and catchment area. Thesis studies total mercury content and mercury bioaccumulation in cyprinid fish. The species included in the study are roach (Rutilus rutilus), bream (Abramis brama), bleak (Alburnus alburnus), white bream (Blicca bjoerkna), blue bream (Ballerus ballerus), ide (Leuciscus idus), tench (Tinca tinca), rudd (Scardinius erythrophthalmus) and crucian carp (Carassius carassius). Three main research questions were: (1) Can diet of different cyprinid fish explain the mercury content? (2) Is mercury content consistent between fish species in different lake types, or does lake type affect mercury content? (3) Is mercury bioaccumulation consistently similar between fish species between lake types? The fish samples for this study were gathered prior to MSc during July-August in 2020 and 2021 from Kukkia, Hauhonselkä and Pääjärvi, which are classified as mesotrophic lakes, and from eutrophic Vesijärvi, Tuusulanjärvi and Hulausjärvi. Total length, weight, sex, sexual maturity, condition factor (K), fish diet and muscle total mercury content were determined from each fish. The diet of the fish and the differences in the total mercury content were tested with analysis of variance. Mercury bioaccumulation was tested with using linear regression analysis and the slope coefficient obtained from the regression equation was tested for bleak and roach with t-test. From the abundant species of the study the highest length corrected (to length 16.6 cm) mercury contents were measured in bleak and roach, while the contents were lower in white bream and bream. The mercury content differed most clearly in species whose feeding behaviour was very specialized. For example, the differences in mercury contents between bleak, which mainly consumes surface insects and zooplankton, and bream, which prefers benthic food, were clear in every lake studied. Mercury contents were mainly higher in mesotrophic lakes compared to eutrophic lakes, but results varied by species. In addition to fish diet and lake type, fish’s metabolism, growth rate and life cycle length probably influenced the species-specific mercury contents. When comparing the abundant species, the bioaccumulation of mercury was steepest in bleak and roach. Compared to these species’ bioaccumulation was slower in white bream and bream. When comparing mercury bioaccumulation within species between different lake types, the differences were species-specific. For example, the bioaccumulation of bleak was consistently steeper in mesotrophic lakes compared to eutrophic lakes, but the bioaccumulation of white bream was steeper in eutrophic lakes. Based on this study, it can be concluded that mercury content and bioaccumulation in cyprinid fish were influenced by e.g., species-specific characteristics, fish diet and level of the lake productivity. In addition to these factors, mercury content and bioaccumulation of fish may have been affected by the land use of the lake catchment area, as well as the anoxic areas of the lakes, which are propitious places for methylation. This study provided valid information on which factors may be relevant for cyprinid fish when observing their mercury content and bioaccumulation.
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(2019)Parvoviruses are among the smallest known viruses. The parvovirus genome is a single stranded DNA, approximately 5 kb in size. The virion has a small (20 to 30 nm), rugged, non-enveloped icosahedral capsid. Parvoviruses can cause a number of diseases. Possibly the most recognized human parvovirus is parvovirus B19 (B19V), which can cause the so-called fifth disease, anemias and fetal death. Another relatively well characterised parvovirus is human bocavirus 1 (HBoV1), which causes respiratory tract infections in young children. Bufavirus (BuV) tusavirus (TuV) and cutavirus (CuV) are emerging parvoviruses, discovered during the years 2012-2016 using next generation sequencing methods. All three viruses were originally discovered in feces of patients suffering from diarrhea. BuV was originally found in Burkina Faso and has since been detected in fecal samples with polymerase chain reaction (PCR)-based methods from Europe, Asia and Africa. The seroprevalence of BuV differs between countries. TuV was found in a single stool sample from Tunisia, but no further reports of it have since emerged. CuV was found in 2016 and it has been linked to cutaneous T-cell lymphoma, but it is not known if the virus is the cause of the cancer or if the virus simply prefers quickly dividing cancer cells for its replication. BuV, TuV and CuV belong to the Protoparvovirus genus, but it is still unclear whether TuV is a human pathogen. More research is needed to study the epidemiology of these viruses and their role in illnesses. There were two main aims in this thesis: to set up an IgM µ-capture enzyme immunoassay (EIA) for human protoparvoviruses using BuV1 as an example and to screen three stool sample cohorts for BuV, TuV and CuV using an in-house multiplex quantitative PCR (qPCR). The IgM EIAs developed for B19V and HBoV1 was used as the base for developing human protoparvovirus IgM EIA, using Virus-like particles (VLP) as antigens. Setting up the EIA required a great amount of optimization and finally troubleshooting, since the assay did not work as expected. The troubleshooting revealed that the ambiguous results in the IgM µ-capture EIA were possibly due to degraded VLPs or that the sensitive µ-capture format requires extremely carefully purified VLPs. More optimizing is needed for this assay, however, the work done in this thesis offers a good base for further development of protoparvovirus IgM EIA. All three viruses were found in the stool samples during multiplex qPCR screening. Based on the qPCR and sequencing results one sample was positive for BuV DNA, one sample for TuV DNA and a total of 12 samples for CuV DNA. This is the first time TuV DNA has been found since its discovery. In addition to that, CuV DNA was identified in fecal samples for the first time since the discovery, previously CuV DNA had been found mostly in skin biopsies. As for TuV, based on the parvovirus phylogenetic analyses, its sequence is more closely related to rodent parvoviruses than CuV or BuV. More research is needed, possibly with animal and human samples, to establish the role of TuV as a human virus.
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(2022)Clathrin-mediated endocytosis is the most common pathway by which cells internalize cargoes from the membrane. It is a critical process in cell communication, development, and homeostasis. In order to study endocytic dynamics, it is critical that one can clearly distinguish receptors that have entered the cell from those which remain on the cell membrane. Current techniques for investigating endocytosis rely on removing membrane-bound components with harsh treatments which may interfere with cell physiology, and often depend on antibodies which are not widely available and - even when they are - may give unreliable signals and may affect receptor behavior and internalization rates. Additionally, a large portion of studies on clathrin-mediated endocytosis have been done on a single receptor, the transferrin receptor. Here we have developed a new assay which resolves the above issues through use of a novel protein probe. This fusion protein will allow us to resolve the issues with current endocytic assays mentioned above, and in theory can be used to study any membrane receptor which is endocytosed. Our preliminary results show that we can use our protein to effectively track endocytosed receptors without interference from signal of receptors remaining on the cell membrane. This shows that our protein may be a powerful tool for studying endocytosis across a wide variety of membrane-bound receptors.
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(2020)Russia’s energy security is considered to rest on hydrocarbon exports, as the country’s economy and political regime depends on revenue generated in energy trade. Today, Russia faces a problem, as interests toward climate change mitigation and renewable energy have increased globally. Particularly the EU, Russia’s primary gas trade partner, seeks to reduce fossil fuel consumption due to its climate policy targets and concerns over energy security. Via the Yamal LNG project, Russia begun to diversify its markets toward East Asia in 2017. The project is expected to spur energy infrastructure development in the Arctic region, as it ships liquefied natural gas (LNG) along the Northern Sea Route. This study finds out how the stakeholders of the Yamal LNG project consider it to connect with the energy security of Russia, to which climate change mitigation poses a potential threat. Since securitization of energy is the result of a social process where political actors contest over the meanings of energy, the study also looks at whose interests the Yamal LNG project actually secures as “energy security”, and how that concept becomes projected as a general national interest, instead of having energy transition among the top objectives of energy policy. Neo-Gramscian analytical approach and frame analysis are used to deliver results from a data consisting of 11 research interviews and 40 archival sources. The stakeholders make sense of Yamal LNG’s relation to energy security and energy transition through four frames, which reflect distinct interest groups. The stakeholders appeal on others by utilizing the frames discursively, as they strategically contest over the meanings of energy. Ultimately, a hegemonic group consisting of the Russian state, JSC Yamal LNG shareholders, industrial organizations, and fossil energy lobbies determines the meanings of Yamal LNG’s production as general interests. Subordinate groups, including environmental NGOs and local indigenous residents, consent as they face combinations of discursive, organizational and material power. With the concession of others, the hegemonic group is able to project a “reality” that presents natural gas production as compatible with energy transition and climate change mitigation as an inferior interest to energy security. The Yamal LNG case shows that incumbent fossil energy regimes can effectively counter attempts to direct energy policy on low-carbon paths by pleading to security, which is a topic that research often neglects.
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(2019)Synthetic biology is an emerging interdisciplinary field of biology that aims to system-atically design artificial biological systems. As synthetic biologists seek increasingly complex control over cellular processes to achieve robust and predictable systems. A new frontier in synthetic biology is engineering synthetic microbial consortia. This ap-proach employs the concept of division of labor, instead of introducing large genetic cir-cuitry to homogenous cell populations. In this approach, different cell types are assigned to execute a portion of the overall circuit. Each cell type communicates with their co-worker subpopulations to complete the circuit. The main advantage of this strategy is the reduced metabolic burden on each cell type. Thus, leading to more reliable and stable overall performance. In this work, to simplify cellular communication between the mem-bers of the consortium, we used the simple architecture of quorum sensing machinery. We constructed a toolbox that contains promoter, receptor and quorum sensing signal synthase genes along with fluorescent reporters. Using this toolbox, we constructed dif-ferent cell types that can be used in synthetic consortia forming various communication topologies. We characterized the constructed cell types individually and in co-cultures.
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(2012)The Arctic region is experiencing significant environmental, social and geopolitical changes as climate change impacts the region and thaws the Arctic sea-ice. The notable amount of emerging hydrocarbon and other resources as well as new navigation routes have attracted a lot of interest by a variety of Arctic and non-Arctic actors. The European Union (EU) has been one of these actors. The Arctic affairs have gained increasing attention within its institutions since the launching of the EU s Arctic policy in 2008. The purpose of this study is to find out how the Arctic is perceived in the eyes of the EU as well as how and to what extent the environmental dimension emerge in relation to other topics. A secondary purpose is to examine how these perceptions have changed since 2008. A comprehensive material is used, covering all relevant EU documents. The material is analyzed using a three-staged coding method within Grounded theory. The EU documents discuss several important topics relating to the Arctic region. This study identifies six categories of these topics. These relate to the changes that the Arctic region is facing, the emerging resources, the geopolitical situation and the governance of the region, the EU s role in the Arctic as well as the protection of the Arctic environment. The qualitative approach is mixed with quantitative aspect to find out how much attention each of these concepts get in the documents and how significant the environmental dimension is compared to the other concepts. The EU is globally recognized as an ambitious environmental actor. This study shows that the environmental aspects are well represented also in the EU s Arctic policy documents. The focus of the documents has changed over the years from Arctic resources and a range of problems towards the importance of cooperation and environmental protection in the region. Environmental protection has been motivated by the responsibilities that the EU feels towards the region. However, a goal has simultaneously been to be acknowledged as a legitimate Arctic actor, which would highly benefit the EU in a number of ways. There is nonetheless reason to presume that the EU is serious in pursuing protection of the Arctic environment and this cannot be seen merely as a means to achieve other ends.
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(2019)Neurotrophin, Brain-derived neurotrophic factor (BDNF) and its cognate receptor Tropomyosin receptor kinase B (TrkB), have been concomitantly linked with neuronal plasticity as well as antidepressant mechanism of action. Adult hippocampal neurogenesis involves proliferation and survival of new-born neurons and has been related to antidepressant mechanisms and cognitive improvement. Environmental enrichment (EE) enhances adult hippocampal neurogenesis (AHN) and induces anxiolytic-like effects. This study postulates that EE-living conditions could restore the abnormal serotonergic modulation on AHN of our transgenic mice. In this study, a transgenic mouse line wherein TrkB receptor is compromised from serotonergic neurons and AHN found to be impaired was used. To assess the behavioural effects and the changes in learning and memory tasks produced by 10-weeks of EE, a behavioural battery test was performed. Our results suggested anxiolytic-like effects from EE in the transgenic mice. Likewise, cognitive improvements were also observed in both control and transgenic mice promoted by EE. Moreover, hyperactivity observed in transgenic mice in standard conditions could be rescued, and no phenotypical differences were observed between control and transgenic mice subjected to EE. To further study the effects of EE on AHN, cellular proliferation and survival were studied through the incorporation of BrdU. The results indicate that the abnormal serotonergic regulation of AHN was rescued upon EE-living conditions. Moreover, molecular methods used to measure the alteration of gene expression revealed significant upregulation of genes related to neuronal plasticity and epigenetic modifications. Altogether, these results suggest EE promotes the neuronal plasticity, rescues the impaired regulation of AHN and modulates the genetic expression of the transgenic mice. Findings from this study could provide new insights regarding novel targets that could modulate adult brain plasticity.
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(2021)Electronic waste is the fastest growing type of waste stream in the world, and this development results from the rapidly accelerating digitalization. Electronic devices become obsolete on an accelerating speed, as there are constantly more powerful devices coming to the market. The most significant environmental impacts of this development are greenhouse gas emissions and natural resource consumption. Circular economy has been proposed as a solution to these environmental challenges, and the goal of this approach is to preserve the value of the materials in the circulation as efficiently as possible. One way of implementing the principles of circular economy is the product-as-a-service-based business model. This research examines the differences between the product-as-a-service-based model and ownership-based model in terms of the environmental impacts that are related to the laptop and tablet procurements. The results of this thesis will be utilized in implementing the actions of the City of Helsinki’s Roadmap for Circular and Sharing Economy. This research was conducted as streamlined life cycle assessment, in which the systematic literature review was used for tracking the environmental impacts of the products’ life cycle stages and components. In addition, expert interviews were carried out in order to collect information about the reuse and recycling practices of the supplier companies that follow these previously mentioned business models. Finally, based on the results of the systematic literature review and the interviews, the company specific differences were assessed in terms of the greenhouse gas emissions and material waste that result from the procurements. The City of Helsinki’s annual procurement volumes were used in this assessment. Based on the results of this research, production and use are the most significant life cycle stages in terms of the devices’ greenhouse gas emissions. Printed circuit boards/printed wiring boards, integrated circuits, displays, and casings are the components with the most significant impact. The results suggest that increasing the lifespan of the devices provides opportunities for significantly lowering impacts in both impact categories, if the devices are efficiently recycled after this.
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(2022)Environmental sustainability and environmentally responsible management have found their way as discussion topics in the Finnish contemporary art field. The contemporary art event Helsinki Biennial chose to make environmental sustainability as one of their corner stones of producing the event (Taskinen et al 2021). In this master’s thesis I assess the environmental responsibility of Helsinki Biennial and how its environmental actions reflect on the expectations of the contemporary art field in Finland from a managerial perspective. The research was conducted through autoethnographic and content analysis methods. This research will try to answer three questions 1. What environmental actions were taken and how were they selected? (R1) 2. How do the environmental action taken compare to the current expectations of environmentally responsible management in the Finnish contemporary art field? (R2) I am also interested in finding out 3. What types of hopes and concerns about future work are identified by Helsinki Biennial organizers and other experts in the Finnish contemporary art field? (R3) The results show that Helsinki Biennial compared well on the expectations of the field. Based on the answers of the interviewees, there is a lot of potential and moti-vation within the field which waits to be unleashed, for example through new financ-ing and travel policies and by increasing the knowledge and time resource of em-ployees. This study also found out about the future visions regarding environmental matters within the contemporary art field.
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Epäorgaaninen hiili Itämeressä : komponenttien jakautuminen ja niiden väliset vuorovaikutussuhteet (2010)Carbon dioxide (CO2) is the most significant greenhouse gas produced by mankind. The oceans play a significant role in the global carbon cycle. Due to its restricted size the Baltic Sea doesn't play an important role as a global reservoir. However, due to its large annual fluctuations, alternations in salinity in the different basins, and a wide drainage-basin with varying soil, it is an excellent study system. The aim of this research was to examine both the vertical and the horizontal distributions of the components of the inorganic carbon in the Baltic Sea, their interactions and annual fluctuations. In addition, the long-term alterations of the surface water pH were reviewed. The study was performed at the Finnish Meteorological Institute as a part of an international research programme regarding the Baltic Sea (BONUS: Baltic-C). The total alkalinity in the Baltic Sea was found to be determined mainly by salinity. Surface water alkalinity is controlled by mixing of highly saline waters originating in the North Sea and waters of low salinity from the rivers draining into the Baltic Sea. The amount of total alkalinity entering the Baltic Sea through the rivers is dependent on the soil quality in the catchment area. According to the alkalinity-salinity-relation, the Baltic Sea can be divided into four distinguishable basins. The alkalinity is lowest in the Bothnian Bay and grows towards the Kattegat as a function of salinity. Salinity controls alkalinity, which together with biological activity controls the concentration of total inorganic carbon. The distribution of total inorganic carbon is very similar to that of total alkalinity. The results in this study support earlier findings on total inorganic carbon and total alkalinity in the Baltic Sea. As the atmospheric partial pressure of carbon dioxide (pCO2) rises, the partial pressure in the surface waters rises as well. In addition to the concentration of total inorganic carbon, the biological activity has a great impact on the annual fluctuations of pCO2. The primary production forms the basis of the biological uptake of carbon dioxide in the surface waters. The results indicate that the Baltic Sea fluctuates from being a source to being a sink for atmospheric CO2 according to the annual fluctuations in primary production. However, simultaneous measurements on the atmospheric pCO2 are needed to ascertain the assumptions on the direction of CO2 flux between the sea and the atmosphere. The rise of the pCO2 in water leads to descending pH levels, because of a relative shift in the components of total inorganic carbon. The results indicate a slight decreasing trend in pH levels In the Baltic Sea during the 30-year observation period, however more research on the subject is needed. The reliability of pCO2-values calculated from known parameters was estimated by comparing them to the measured values. The study shows that pCO2 results for the Baltic Sea derived from the program developed for the oceans, should be used with caution.
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