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  • Leino, Kaisa (2020)
    Tutkin metsien käytön kehystämistä Suomen ja Ruotsin ilmasto- ja energiapolitiikassa.Tutkielman tavoite on tutkia, kuinka metsien käyttöön litttyviä, keskenään ristiriitaisia tavoitteita käsitellään Suomen ja Ruotsin ilmasto- ja energiapolittiikassa ja etenkin biotalous-käsitteen yhteydessä. Biotalous esitetään kummankin maan aineistossa tärkeänä keinona kasvihuonekaasujen vähentämiseksi, mutta sen haasteena ovat metsien hiilivarastojen pieneneminen ja luonnon monimuotoisuuden heikentäminen lisääntyvien metsähakkuiden takia.Tutkimuskysymykseni on, miten metsien käyttöä kehystetään Suomen ja Ruotsin ilmasto- ja energiapolitiikoissa. Tarkentavia tutkimuskysymyksiä ovat: miten biotalouden merkitys kehystetään maiden ilmasto- ja energiapolitiikassa; kuinka metsien käyttöä perustellaan osana biotaloutta; ja kuinka metsiin liittyviä, keskenään ristiriitaisia tavoitteita sovitetaan yhteen? Tutkimusmenetelmänä on kehysanalyysi, joka on diskurssintutkimuksen alalaji. Diskurssintutkimuksen keskeinen idea on, että todellisuus rakentuu kielen kautta, ja sitä tutkimalla on mahdollista tarkastella, millaisia arvoja ja ideologioita argumentoinnissa käytetään. Kehysanalyysin tarkoitus on tutkia tietyn aiheen käsittelyä aineistossa ja tutkia, millaisena ongelmana se esitetään, mitä ratkaisuehdotuksia siihen tarjotaan, ja mitä valitut argumentit kertovat siitä, millaisia arvoja ja ideologioita kehystämisen taustalla on. Tutkimuksen keskeisin tulos on, että Suomen ja Ruotsin ilmasto- ja enerigapolitiikassa on vahva biotalouskehys, joka on seurausta maiden pitkistä metsäteollisuuden perinteistä. Koska maat ovat sitoutuneet kansainvälisiin ilmasto- ja kestävyystavoitteisiin, kuvaan biotalouskehyksiä maiden ilmastonmuutoksen yleiskehyksen näkökulmasta, sillä kansainväliset sitoumukset ja tavoitteet vaikuttavat merkittävästi siihen, kuinka metsien käyttöä kehystetään maiden biotalouskehyksissä. Tutkimukseni perusteella johtopäätökseni on, että biotalous kehystetään keskeisenä osana energiamurroksen toteuttamista, ja että biotalous-käsitettä käytetään sovittelemaan yhteen metsien käyttöön liittyviä ristiriitaisia tavoitteita. Kummankin maan tavoitteena on kestävän energiamurroksen toteuttaminen ilman, että luonnon monimuotoisuus tai muut ympäristöarvot kärsivät. Tutkimuksen tulokset kuitenkin osoittavat, että kestävyytta tarkastellaan lähinnä talouden näkökulmasta, sillä muiden kestävyyden ulottuvuuksien saavuttamiseksi esitetä vakuuttavia toimenpiteitä. Maiden biotalouskehyksissä on paljon yhteisiä piirteitä, mutta myös merkittäviä eroja, joista osa selittyy maiden ilmastonmuutoksen yleiskehyksen kautta. Jotta maiden metsien käyttöön liittyviä ristiriitoja voisi tutkia monipuolisemmin, olisi ilmasto- ja energiapolitiikan tavoitteiden ja ratkaisuehdotusten vertaaminen toteutuneisiin politiikkatoimenpiteisiin hedelmällinen lähtökohta tulevalle tutkimukselle aiheesta. Toinen mielenkiintoinen tutkimusteema olisi tutkia tarkemmin, mistä erot Suomen ja Ruotsin metsäpolitiikassa johtuvat.
  • Pääkkönen, Jekaterina (2019)
    Tämä on tapaustutkimus Helsingin satamasta uudenlaisten turvallisuuskysymysten, hybridiuhkien, aikakaudella. Suomi ja Suomen elinkeino ovat riippuvaisia meriliikenteestä ja tämän vuoksi satamat, meren ja maan risteyskohdat, on määritelty kriittiseksi infrastruktuuriksi. Koska kriittinen infrastruktuuri on yksi mahdollinen hybridivaikuttamisen kohde, tulisi satamien resilienssiä tarkastella myös tällaisten vaikeiden uhkien näkökulmasta. Näin ollen tutkielmassa vastataan kahteen tutkimuskysymykseen: millaisia resilienssiaukkoja Helsingin sataman varautumisessa, ennakoinnissa ja hallinnassa on, ja miten hybridiuhan olemassaolo muuttaa näitä resilienssiaukkoja. Tarkoitus on kartoittaa ensin yleisesti sataman resilienssiaukkoja, koska niitä on ilman hybridiuhkaakin. Löydettyjä aukkoja tarkastellaan kuitenkin tämän jälkeen hybriuhkien näkökulmasta, koska erilaisena uhkana ne vaikuttavat perinteiseen varautumiseen ja hallintaan. Tutkielma osallistuu laajemman WISE-projektin resilienssiaukkoja kartoittavaan työhön. Resilienssiaukkojen havaitsemisen lisäksi tavoite on esittää uusia näkökulmia resilienssin kasvattamiseksi yllätyksellisiä uhkia vastaan ja osoittaa, kuinka hybridiuhat muuttavat perinteistä varautumis- ja hallintatyötä satamassa. Näkökulmana ja teoreettisena viitekehyksenä toimivat korkean luotettavuuden (high reliability organization) ja tolkullistamisen (sensemaking) teoriat. Analyysi perustuu kolmeentoista haastatteluun ja Huoltovarmuuskeskuksen käsikirjaan. Aineistolle on tehty sisällönanalyysi. Tutkimustuloksina on esitetty yhdeksän resilienssiaukkoa, jotka liittyvät redundanssin puutteeseen, liialliseen määrittelyyn, rutinoitumiseen ja asenteeseen, jossa häiriöiden puute nähdään osoituksena organisaation luotettavuudesta. Hybridiuhka puolestaan muuttaa ja monimutkaistaa resilienssiaukkoja erityisesti sen tulkinnallisen luonteen vuoksi. Sen olemassaolo myös kyseenalaistaa perinteisesti resilientteinä pidettyjä toimintatapoja. Nämä tulokset ovat kuitenkin vasta alku, ja seuraavissa tutkimuksissa tulisi syventyä enemmän sataman käytännön toimijoiden tapoihin ja rutiineihin. Myös tilannekuvien tekeminen ja niistä syntyvät määritelmät ovat kiinnostavia jatkotutkimuksen kohteita valituista näkökulmista. Sama aihe tarjoaa myös kiinnostavan väylän syventyä enemmän kriittisen infrastruktuurin resilienssiin ja erityisesti eri toimintojen keskinäisriippuvuuksiin, joiden pintaa tässä tutkielmassa vain raapaistaan.
  • Mahmood, Hamid (2019)
    Nucleosides are one of the fundamental building blocks of the cell and are precursors of DNA and RNA and serve as universal signalling molecules for cell surface receptors. These nucleosides play vital roles in myriad of physiological processes, such as cardioprotection, platelet aggregation and coronary vasodilation. In clinical settings, synthetic analogs of nucleosides are used as therapeutic against cancer and other viral diseases. In human, uptake and regulation of nucleosides and their analog drugs is facilitated by the two families solute carrier membrane transporter proteins (SLC); SLC28 and SLC29. SLC29 consists of four human equilibrative nucleoside transporter members (hENT1-4) with different sub-cellular localization, tissue distribution and substrate selectivities. Human equilibrative nucleoside transporter 1 (hENT1) is the major plasma membrane nucleoside transporter and has shown to play an important role in adenosine signalling and anticancer therapies. Despite the significant physiological and pathophysiological role, little is known about the structure and molecular function of ENT homologs. Structural studies of hENT1 and other nucleoside transporter is hampered by their low expression and hydrophobic nature. The aim of this thesis work is to find suitable nanobodies (Nbs) that may serve as crystallization chaperone to facilitate the structural studies of hENT1 transporter. Camelid heavy chain only antibodies (Nanobodies) raised against recombinant hENT1 were screened for their suitability for future structural investigation of hENT1. Selected nanobodies were expressed and purified from E.coli cell in milligram quantities. Affinity of nanobodies with hENT1 was assessed using co-elution on size exclusion chromatography. High affinity binders were further screened for their ability to conformationally stabilize hENT1. In future, high affinity nanobodies will be explored for x-ray crystallization and single particle cryo-electron microscopy of hENT1. For cryo-EM it's important to convert the selected Nbs into megabody which constitute large scaffold proteins. 3D structure determination of hENT1 will be significant in understanding its molecular function and to accelerate rational drug designing against cancer, HIV and other viral infections.
  • Heinonen, Reija (2020)
    Mining of sulfide minerals produces acidic effluents rich in soluble metals and sulfate. The effluents pose a risk to the environment and must therefore be treated prior to their release. Conventionally, effluents are neutralized, and remaining metals are precipitated as hydroxides by means of alkaline minerals or industrial chemicals. The process leads to a formation of large amounts of disposable sludge containing valuable metals. Efforts are needed for more sustainable and resource efficient water treatment in the spirit of circular economy. Nanofibrillated cellulose (NFC) adsorbents are a promising and sustainable alternative to conventional treatments as cellulose is the most abundant natural polymer. In addition, NFC can be prepared from industrial byproducts and its surface properties can easily be modified to adsorb pollutants with different chemical properties. Understanding the adsorption mechanisms is essential for the rational development and use of NFC in water treatment and environmental protection in the future. Based on previous studies, anionic NFC retains metal cations and sulfate anions simultaneously from aqueous solutions. However, the adsorption mechanisms in conditions comparable to e.g. authentic mining water with high metal salt concentrations are poorly understood. In this Master’s Thesis work, adsorption experiments with pure metal salt solutions of increasing metal concentrations (0-800 mM) were carried out to investigate the adsorption mechanisms of metal cations and anions. Based on previous studies five cations with different chemical properties were chosen: Na⁺, Mg²⁺, Mn²⁺, Al³⁺ ja Fe³⁺. The adsorption was examined in both metal chloride and sulfate solutions to also elucidate the co-adsorption of counter ions and their possible effects on metal adsorption on NFC. The Freundlich adsorption isotherm model was utilized to analyze the adsorption of metals. In addition, removal percentages were calculated for both metal cations and their counter anions. NFC was observed to retain all metal cations equally regardless of their different properties and pH-values of the metal salt solutions. The removal percentage of both cations and anions ranged mainly between 14–20 % and the removal capacity of NFC decreased only slightly with increasing initial concentrations. No remarkable differences were observed in the adsorption isotherms of different metals and the adsorption was almost linear in the whole concentration range. Despite the relatively low removal percentages, the amounts of metals adsorbed by NFC (mmol/g dry weight) were tenfold compared to those previously obtained in many studies. According to the results, NFC adsorbed cations non-specifically with weak interactions and the dominating adsorption mechanism resembles physical rather than chemical adsorption. Upon the adsorption of cations, an equal amount of negative charge was co-adsorbed and hence the adsorption of anions was deemed electrostatic in nature.
  • Hardwick, Bess (2008)
    A parabiologist is an assistant in biological research without formal academic training. In this study, I use volunteer parabiologists to conduct a national survey of oak cynipid gall wasps, tribe Cynipini (Hymenoptera: Cynipidae). My objectives were to produce an updated list of Finnish oak cynipid species, to map the distribution of these species, and to examine factors that could have an effect on local species richness and on the regional distribution and local abundance of individual species. I also wanted to examine whether the two generations of a species tend to occur on the same or on different individual trees. Empirical data on local gall wasp assemblages were collected by over a hundred volunteers from all over Finland, mostly people with a general interest in nature. Since most gall wasps occur as two discrete generations, volunteers sampled oak trees twice during the summer of 2007, with the spring round encompassing 218 trees and the autumn one 180. From each tree, five half-metre branches were examined, followed by a ten-minute scan of the rest of the branches. The recovered samples were then sent to me for identification. Based on tree-specific information supplied by the volunteers, I used generalised linear models to examine the effects of the number of neighbouring oaks, of oak circumference and of sampling location on the species richness of gall wasps, on the local incidence of species and on their local abundance. The survey produced data on 16 oak cynipid species, two of which were new to Finland. These new records bring the total number of species recorded in Finland up to 21. The centre of oak cynipid species richness was in the southwest, but some species were found as far north as Ostrobothnia. Within some species, different generations occurred on different individual trees. For this reason, I separated the generations in the distribution maps and statistical analyses. Against a backdrop of large-scale clines in species richness, local species richness was affected by the number of neighbouring oaks and by tree circumference. Large oaks that are surrounded by many other oaks support the most species-rich communities of oak cynipids, and the local incidence of certain species and of generations within species exhibit similar patterns. To conclude, oak cynipids are suitable targets for sampling by parabiologists, and this survey has improved our knowledge of the Finnish oak cynipid fauna. Oak cynipids have successfully spread beyond the host plant's narrow natural distribution and colonised the planted trees in the north. Since large oaks close to other oaks exhibit the most diverse gall wasp communities, the natural old oak forests in the southwest of Finland are particularly important to these species.
  • Kurkinen, Karoliina (2019)
    Semantics is a study of meaning in language and basis for language comprehension. How these phenomena are processed in the brain is still unclear especially in naturalistic context. In this study, naturalistic language comprehension, and how semantic processing in a narrative context is reflected in brain activity were investigated. Subjects were measured with functional magnetic resonance imaging (fMRI) while listening to a narrative. The semantic content of the narrative was modelled computationally with word2vec and compared to voxel-wise blood-oxygen-level dependent (BOLD) brain signal time courses using ridge regression. This approach provides a novel way to extract more detailed information from the brain data based on semantic content of the stimulus. Inter-subject correlation (ISC) of voxel-wise BOLD signals alone showed both hemispheres taking part in language comprehension. Areas involved in this task overlapped with networks of mentalisation, memory and attention suggesting comprehension requiring other modalities of cognition for its function. Ridge regression suggested cerebellum, superior, middle and medial frontal, inferior and medial parietal and visual cortices bilaterally and temporal cortex on right hemisphere having a role in semantic processing of the narrative. As similar results have been found in previous research on semantics, word2vec appears to model semantics sufficiently and is an applicable tool in brain research. This study suggests contextual language recruiting brain areas in both hemispheres and semantic processing showing as distributed activity on the cortex. This activity is likely dependent on the content of language, but further studies are required to distinguish how strongly brain activity is affected by different semantic contents.
  • Juurikka, Veera (2023)
    Global warming should not rise beyond 1.5°C, which means that all sectors in the economy are needed to reduce greenhouse gas emissions. The need for corporations to account their value chain emissions has sprung a variety of accounting and reporting standards. In response, Greenhouse Gas protocol established the Corporate Value Chain (Scope 3) Accounting and Reporting Standard. However, the success of the scope 3 emission accounting has been determined to be insufficient. The unsuccess of scope 3 emission accounting and reporting can be explained with the challenges that have been widely identified. Nevertheless, the identified challenges do not provide a deeper understanding of why they hinder the success of scope 3 accounting and reporting. This thesis delves into the challenges of scope 3 accounting by investigating four Finnish food industry corporations. The study for this thesis was conducted as semi-structured interviews of seven experts who work with the scope 3 accounting and reporting of their corporation. The interviews were held in May of 2022 and theory guided thematic analysis was used to analyze the results. The results show that there are challenges concerning measurement and evaluation, knowledge and guidance and communication. The measurement and evaluation challenges include data collection challenges, data quality challenges and data processing challenges. The key finding from this study is that most of these challenges are highly connected. The reporting corporation and suppliers’ resources and guidance play a key role in data collection and how accurate data can be obtained for the GHG inventory. These affect the comparability of gained emission factors and how comparable the emission information of products, production lines and corporations are. The findings of this study share understanding of the complexity of scope 3 accounting challenges.
  • Lepistö, Santeri (2023)
    Efficient processing of auditory information begins to emerge early in human ontogeny and establishes foundations for learning language from speech exposure. Here we show that repeated exposure to spoken words causes in neonatal brain attenuated neural responses that are linked to language skills at the age of 24 months. In the study, 75 newborn infants were exposed to repeated presentation of two spoken disyllabic pseudowords. During the word exposure, event-related potentials to presented pseudowords were measured with electroencephalography. The study provides three kinds of findings regarding neonatal brain dynamics and repetitive word exposure. Firstly, the results show that continuous exposure to spoken pseudowords modulates neonatal brain activity and can lead to attenuation of neural responses. This neural suppression likely reflects neonates’ early capacity to recognize spoken words and form neural representations of the stimuli through repetition. Secondly, the attenuated neural responses were bound to the presentation of the first syllable and did not occur after presentation of the second syllable. Thirdly, occurrence of neonatal neural suppression was associated with better expressive language skills later, at the age of 2 years. Altogether, the results provide preliminary evidence that neonatal brain responses to word repetition can be utilized to indicate efficiency of learning language from speech exposure and later state of language development.
  • Mauranen, Aleksanteri (2018)
    Tässä maisterintutkielmassa tutkin romanialaisen taloustieteilijän Nicholas Georgescu-Roegenin (1904–1994) vaikutusta ekologisen taloustieteen koulukunnan muodostumiseen. Laadullisen sisällönanalyysin keinoin tutkin Georgescu-Roegenin avainajatuksia kahdeksan tekstin (artikkeleita, luentoja ja postuumisti julkaistu käsikirjoitus vuosilta 1970–1989) valossa ja vertaan niitä ekologisen taloustieteen ominaispiirteisiin. Teen myös katsauksen Georgescu-Roegenia käsittelevään kirjallisuuteen ekologisen taloustieteen kentällä. Näin saan kaksi näkökulmaa hänen intellektuaaliseen vaikutukseensa. Kirjallisuuskatsauksen perusteella arvioin myös Georgescu-Roegenin sosiaalista vaikutusta ekologisen taloustieteen syntyvaiheilla. Kaiken kaikkiaan selvitän Georgescu-Roegenin avainajatuksia ekologisen taloustieteen kannalta ja hänen roolejaan koulukunnan varhaisessa kehityksessä. Georgescu-Roegenin keskeiset ajatukset jäsentyvät työssäni 24 teeman alle, jotka vuorostaan muodostavat viisi kattoteemaa. Ensimmäinen kattoteema, entropia ja luonnontieteet, kuvaa Georgescu-Roegenin ajattelun läpäisevää biofyysistä maailmankuvaa, jota ilman hänen johtopäätöksiään ei voi syvällisesti ymmärtää. Toinen kattoteema, ihmiskunnan historia ja tulevaisuus, kattaa hänen käsityksensä ihmisestä ja ihmiskunnasta sekä erityisesti siitä auttamattoman kestämättömästä tilanteesta, johon entropian laki hänen mukaansa ihmiskunnan sitoo. Kolmas kattoteema, varsinainen taloustiede, käsittelee Georgescu-Roegenin käsityksiä taloustieteen filosofisesta perustasta, sen teoreettisista ja käsitteellisistä ongelmista sekä eräitä teknisempiä ja matemaattisempia erityiskysymyksiä. Neljäs ja viides kattoteema muodostuvat pääasiassa jo aiemmissa kattoteemoissa esiin tuoduista ajatuksista uudelleen järjesteltyinä: kritiikki kokoaa Georgescu-Roegenin kritiikkiä erityisesti muita tutkimussuuntauksia kohtaan sen kohteen mukaan järjestettynä, ja ratkaisut puolestaan esittelee hänen ratkaisuehdotuksiaan niin taloustieteen kuin koko ihmiskunnankin tasolla. Ekologisen taloustieteen kannalta Georgescu-Roegenin keskeisimmät ajatukset koskevat erityisesti ensimmäistä ja kolmatta kattoteemaa. Aineen, energian ja entropian lain suuri merkitys taloudellisessa prosessissa sekä Georgescu-Roegenin uudelta taloustieteeltä edellyttämät eettinen normatiivisuus ja poikkitieteellisyys ovat ekologisen taloustieteen peruspilareita. Ekologinen taloustiede vastaa monilta osin niihin kritiikkeihin, joita Georgescu-Roegen oman aikansa taloustieteen suuntauksiin kohdisti. Hänen sosiaalis-intellektuaalinen merkityksensä voidaan tiivistää viiteen rooliin: varhainen tiennäyttäjä ja kriitikko; varhainen kokoaja ja teoreetikko; vaikuttava, mutta hankala mentori; kuuseen kurkottava erakko ja kiistelty klassikko. Mahdollisia jatkokysymyksiä samalta suunnalta voisivat olla esimerkiksi Georgescu-Roegenin pääteoksen, The Entropy Law and the Economic Processin (1971), klassikkoaseman tarkastelu tai samantyyppinen vaikutusanalyysi muista ekologisen taloustieteen varhaisista uranuurtajista. Myös ekologisen taloustieteen käytännön tutkimustodellisuuden suhde sen ääneenlausuttuihin periaatteisiin ansaitsisi lähempää tarkastelua. Entropian lakia olisi kiinnostavaa tutkia taloustieteen näkökulmasta joko analysoimalla aiheesta käytyä runsasta keskustelua tai pureutumalla entropian käsitteen antroposentrisyyden ja objektiivisuuden väliseen jännitteeseen.
  • Martikainen, Tuomo (2019)
    Niittyliekosammal (Rhytidiadelphus squarrosus) esiintyy poh-joisen pallonpuoliskon lauhkealla ja viileällä vyöhykkeellä. Suomessa se esiintyy yleisenä Etelä- ja Keskiosissa sekä har-vinaisena tai puuttuvana Lapissa. Laji on heikko kilpailija ja menestyy parhaiten kulttuurivaikutteisilla kasvupaikoilla. Sen arvellaan myös suosivan mereistä ilmastoa. Niittyliekosammal on kaksikotinen, joten siittiö- ja munape-säkkeet ovat eri kasveissa. Kaksikotisilla sammalilla, joiden primaarinen sukupuolijakauma on teoriassa 1:1, on usein vinou-tunut jakauma populaatiotasolla. Pääsyynä vinoutumaan pidetään sukupuolten erilaisia resurssivaatimuksia. Ympäristötekijöiden lisäksi myös perimä säätelee sukupuolijakaumaa. Kaksikotisuus ja vinoutunut sukupuolijakauma alentavat hedelmöittymistoden-näköisyyttä ja niittyliekosammal lisääntyykin pääasiassa kas-vullisesti. Erikoistuneita leviäimiä lajilla ei tunneta, joten tämä tapahtuu irronneiden versojen tai näiden osien avulla. Tämän opinnäytetyön päätarkoitus oli selvittää niittyliekosam-malen sukupuolijakaumaa sekä mahdollisia eroja siinä eri si-jaintipaikoilla kasvavien populaatioiden välillä. Aineisto ke-rättiin Mäntyharjulta sekä Helsingistä ja tutkittujen näyttei-den kokonaismäärä oli 675 kpl. Sukupuolen määritin sukusolu-pesäkkeiden perusteella ja jakaumien vertailuun käytin riippu-mattomuustestiä. Lajin sukupuolijakaumaa ei ole aikaisemmin tutkittu Suomen oloissa, joten tämän tutkimuksen myötä syntyi myös aineistoa eri maiden väliseen vertailuun. Kasvatuskokeen avulla tutkin myös millä verson osilla lajin suvuton lisäänty-minen tehokkaimmin tapahtuu. Kasvimuseon herbaarionäytteiden pohjalta tarkastelin lisäksi niittyliekosammalen ajallista ja paikallista esiintymistä Suomessa. Tutkimukseen kerätyn aineiston perusteella niittyliekosammalen sukupuolijakauma oli naaraspainotteinen. Jakaumat kuitenkin erosivat toisistaan sekä paikkakuntien että saman paikkakunnan populaatioiden välillä. Sukupuolijakaumat erosivat toisistaan myös maiden välisessä vertailussa. Eri ilmastovyöhykkeet voi-vat osaltaan selittää jakaumien eroja paikkakuntien ja maiden välillä. Lisääntymistä selvittävässä kasvatuskokeessa versojen kasvu painottui ainakin alkuvaiheessa sivuhaaroihin. Alkuperäisten sivuhaarojen kasvu oli tehokkainta verson nuoremmissa osissa. Uusien sivuhaarojen tuotto oli yleisempää versoissa, joissa oli mukana verson alempien osien vanhempaa solukkoa. Verson runsas sivuhaarojen määrä korreloi negatiivisesti irtoamisen jälkeiseen kasvuun. Juurtumahapsiston kasvu oli hyvin vähäistä ja irronneiden lehtien avulla tapahtuvaa kasvua ei ilmennyt. Herbaarionäytteitä oli kerätty aikavälillä 1812–2010. Eliömaa-kunnittaisessa vertailussa näytemäärä heijasti pääpiirteissään lajin kirjallisuudessa mainittua esiintymisrunsautta sekä väestöjakaumaa Suomessa. Itiöpesäkkeitä sisältävät herbaario-näytteet oli kerätty Maamme eteläosissa ja niiden suhteellinen osuus oli suurin Karjalan kannaksella ja Ahvenanmaalla. Kym-menvuotiskausilla 1860–1909 itiöpesäkkeitä sisältävien näyt-teiden osuus oli selkeästi suurempi kuin muina ajanjaksoina.
  • Tuokko, Emmi (2022)
    Nitrogen fixation by Sphagnum mosses in a boreal fen ecosystem Emmi Tuokko Master’s Programme in Ecology and Evolutionary Biology Faculty of Biological and Environmental Sciences University of Helsinki May 2022 Faculty: Faculty of Biological and Environmental Sciences Degree programme: Master’s Programme in Ecology and Evolutionary Biology Study track: Ecology and Evolutionary Biology Author: Emmi Tuokko Title: Nitrogen fixation by Sphagnum mosses in a boreal fen ecosystem Level: Master’s thesis Month and year: May 2022 Number of pages: 34 pages + 4 appendix pages Keywords: nitrogen fixation, Sphagnum, boreal fen, acetylene reduction, diazotroph Supervisor: Dr. Juha Mikola Where deposited: HELDA – Digital Repository of the University of Helsinki Abstract: Ecosystems in the North are heavily constrained by nitrogen (N) and the main pathway of N for plants is biological N2 fixation by Sphagnum mosses. Mosses fix N with either free-living, associated or symbiotic diazotrophs and convert it to a plant-accessible form. This way N2 fixation contributes significantly to the level of photosynthesis and carbon sequestration that these ecosystems can maintain. However, diazotrophs are exposed to large fluctuations in abiotic factors and earlier findings have suggested that to affect the rate of N2 fixed. Only a few studies have focused on boreal Sphagnum-dominated fens and thus, I wanted to figure out what environmental factors control N2 fixation activity in this habitat type. Most of the N2 fixing bacteria are heterotrophs but also methanotrophs have been shown to participate in N2 fixation. Therefore, I tested if methane (CH4) flux was connected to N2 fixation activity. As N is a necessary nutrient for plants, I also wanted to see whether the variation in N2 fixation can explain the variation in plant growth and productivity and on the other hand, if the productivity can explain the rate of N2 fixation by providing more energy. To test these interactions, we established the acetylene reduction assay (ARA) on a fen in Northern Finland to measure, how much N2 is fixed. We also recorded environmental factors (soil moisture, soil temperature, air temperature, relative humidity and radiation), measured CO2 and CH4 fluxes and calculated vascular plant coverage and Sphagnum growth from 20 study plots. I expected to find a correlation especially between soil moisture and N2 fixation because earlier studies have shown it to control the fixation activity the most. I found out that leaf area index (LAI) of vascular plants was explained by N2 fixation. This is a significant finding because it has not been proved before. It supports the earlier findings about the connection between N2 fixation and vascular plant photosynthesis. I also discovered that radiation (PAR) and potential gross primary production (GPP1200) explained the variation in N2 fixation in the first measurement. This shows the dependency of N2 fixation on the energy that photosynthesis provides. Contrary to my predictions, none of the other factors explained N2 fixation or were explained by N2 fixation. Further studies about moss-associated N2 fixation are needed especially in the light of future changes in climate and N deposition. Tiedekunta: Bio- ja ympäristötieteellinen tiedekunta Koulutusohjelma: Ekologian ja evoluutiobiologian maisteriohjelma Opintosuunta: Ekologia ja evoluutiobiologia Tekijä: Emmi Tuokko Työn nimi: Rahkasammalten typensidonta boreaalisessa suoekosysteemissä Työn laji: Maisterin tutkielma Kuukausi ja vuosi: 5/2022 Sivumäärä: 34 sivua + 4 sivua liitteitä Avainsanat: typensidonta, rahkasammal, boreaalinen, suo, ARA, diatsotrofi Ohjaaja: Dr. Juha Mikola Säilytyspaikka: HELDA - Helsingin yliopiston digitaalinen arkisto Tiivistelmä: Pohjoisen ekosysteemit ovat erittäin typpirajoitteisia, ja kasvit saavat suurimman osan typestä rahkasammalten biologisen typensidonnan kautta. Sammalet sitovat typpeä joko vapaana elävien tai symbionttisten diatsotrofien välityksellä ja muuttavat typen kasvien käytettävissä olevaan muotoon. Tätä kautta typensidonta vaikuttaa merkittävästi koko ekosysteemin fotosynteesin ja hiilensidonnan tasoon. Diatsotrofit ovat kuitenkin alttiita abioottisten tekijöiden suurelle vaihtelulle, ja aikaisemmat tutkimukset ovat todenneet sen vaikuttavan typensidonnan tasoon. Vain harvat näistä tutkimuksista ovat keskittyneet boreaalisiin minerotrofisiin soihin, joilla rahkasammalet dominoivat, joten halusin selvittää, mitkä ympäristötekijät kontrolloivat typensidonnan aktiivisuutta tällaisessa elinympäristössä. Suurin osa typpeä sitovista bakteereista on heterotrofeja, mutta myös metanotrofien on osoitettu osallistuvan typensidontaan. Sen vuoksi halusin tutkia, onko metaanivuo yhteydessä typensidonnan tasoon. Typen ollessa välttämätön ravinne kasveille halusin myös nähdä, voiko vaihtelu typensidonnan tasossa selittää kasvien kasvua ja tuottavuutta, ja toisaalta, voiko tuottavuus selittää typensidonnan vaihtelua tarjoamalla sille lisää energiaa. Testataksemme näitä yhteyksiä mittasimme typensidontaa asetyleenin pelkistysmenetelmällä Halssiaavalla Sodankylässä. Mittasimme myös ympäristötekijöitä (maan kosteus, maan lämpötila, ilman lämpötila, suhteellinen kosteus, säteily), hiilidioksidi- ja metaanivuota, putkilokasvien peittävyyttä ja rahkasammalten kasvua 20 tutkimusruudulta. Odotin löytäväni korrelaation erityisesti typensidonnan ja maan kosteuden väliltä, sillä aikaisemmat tutkimukset ovat todenneet kosteuden olevan merkittävin typensidontaa säätelevä tekijä. Sain selville, että typensidonta selitti ruutujen välistä vaihtelua putkilokasvien lehtipinta-alassa. Tämä on tärkeä löydös, sillä yhteyttä ei olla todistettu aiemmin. Tulos tukee aiempia löydöksiä typensidonnan ja putkilokasvien fotosynteesin yhteydestä toisiinsa. Ensimmäisten mittausten tulokset osoittivat, että säteily ja potentiaalinen bruttoperustuotanto selittivät typensidontaa. Tämä todistaa typensidonnan riippuvuuden fotosynteesin tarjoamaan energiaan. Vastoin odotuksiani muut tekijät eivät selittäneet typensidontaa, eikä typensidonta selittänyt niitä. Lisätutkimukset sammalten typensidonnasta ovat tarpeen erityisesti ilmastonmuutoksen ja lisääntyvän typpilaskeuman valossa.
  • Kakko, Eeva-Maija (2021)
    The Arctic is home to many Indigenous peoples, including the Sámi. It is also an economically attractive area for governments and companies. Arctic Railway has been planned by the Finnish government and private parties to span over Sápmi, the Sámi homeland. Sámi youth association Suoma Sámi Nuorat, Sámi art collective Suohpanterror, and environmental NGO Greenpeace Finland have collaborated to fight against the railway and organized demonstrations and other campaigning. The goals of this thesis are to find out what kind of themes have been present in these Sámi organizations and Greenpeace’s protests and communication related to the Arctic Railway. Shared priorities and differences in their priorities are also determined. Moreover, this thesis explores how the Sámi are portrayed in the protests against the Arctic Railway. The data of this thesis is derived from public media sources, including news articles, social media content, and press releases. Case study is used as a research approach, and qualitative content analysis is used as a method. A middle ground concept functions as an analytical tool. It refers to a creative process where groups from different cultures find ways to work together. Indigenous peoples and environmentalists have often built strategic alliances, although also having differences in their priorities. In the middle ground, Indigenous peoples are recognized as active, creative agents, but also the use of stereotypes of Indigenous peoples have been present in these kinds of alliances. The results of this thesis show that the Sámi organizations have discussed the railway´s impacts on the Sámi livelihoods, lands, and culture, affecting their future as a people. They have also brought up that the railway has been planned without their consent, and the project has violated both Finnish law and international Indigenous rights. Greenpeace has focused on protecting the northern forests while raising awareness of Sámi issues and appearing as a supporter of Sámi people. They have had their unique middle ground where both priority differences and convergences have been present. In the protests against the Arctic Railway, the Sámi are portrayed as active agents. They have taken action in different ways: through demonstrations, participation in international events, art, and social media activism. This research can raise awareness about the potential of Indigenous-environmental alliances in promoting Indigenous rights and environmental protection and help build better alliances in the future. Further research could look at how these kinds of alliances have been negotiated.
  • Kohonen, Ilmari (2020)
    Global biodiversity continues to decline. Recent reports of decline in insect abundance and biomass are concerning, given the crucial roles insects play in multiple ecosystem processes, such as pollination, nutrient cycling and as a food resource for higher trophic levels. Based on the current state of the literature, it appears that total insect abundance and biomass are in decline, but there is considerable variation in trajectories in different regions and taxa. Many studies report on either aggregated community abundance or biomass, but few have examined how closely these two variables are correlated. For example, declining trends in large-bodied species could have disproportionately large effects on total biomass, even if total abundance remained stable. This, in turn, could have substantial consequences for predators dependent on insect biomass for food. Whether studying total abundance or biomass, long-term monitoring data are essential for robust estimation of temporal trends. In my thesis, I investigated trends in macro-moth abundance and biomass using data from the Finnish moth monitoring scheme (Nocturna) over a period of 24 years (1993-2016). My main objectives were to explore whether total abundance and biomass have changed over the timeframe examined, and to estimate the degree of correlation between the two variables in these data. As is typical for monitoring programs, only counts of moth individuals have been recorded. In order to obtain information on biomass, I created a predictive model for converting the recorded abundance counts to dry biomass based on species mean wingspan and body robustness. I weighed museum collection specimens of common moth species of variable sizes, and used these data for fitting the model. Additionally, I also investigated how local weather (thermal and precipitation) conditions during the growing season and winter relate to interannual variation in total abundance. Finally, I analysed potentially informative species traits (e.g., wingspan, voltinism, overwintering stage) in relation to population trends of individual species, because such associations could be underlying change in total abundance or biomass. There was no long-term change in total macro-moth abundance or biomass over the 24-year monitoring period. Abundance and biomass were very highly correlated (r > 0.9). In terms of interannual variation, total moth abundance and biomass showed a distinctive pattern suggestive of periodicity, with peaks at approximately 10-year intervals. Local weather conditions were very weakly associated with annual change rates of total abundance, leaving the interannual pattern unexplained. Lichen-feeding and multivoltinism (multiple generations per year) were positively related to population trends, supporting earlier findings. Especially relevant to potential trends in biomass, wingspan showed no relationship with positive or negative trends, which is in line with the high correlation between abundance and biomass in this dataset. My results imply that the total abundance and biomass trends in boreal Europe diverge from those commonly reported from temperate Europe. Further research is required to shed light on factors underlying total insect abundance and biomass trends. The method I developed for converting moth abundance to biomass is applicable to similar work elsewhere.
  • Karttunen, Maria (2020)
    The goal of this thesis is to examine whether the EU’s climate policy towards Africa is normative after signing the Paris Agreement. This is done by analysing the goals and means of EU climate policy in this context. The aim is also to find out what elements besides normativity form the EU’s climate policy in this case. The research material consists of public documents from various EU institutions, the Joint Africa-EU Strategy and its Action Plans, and joint statements by EU and African actors. Qualitative abductive content analysis was used as the research method. In the context of international climate policy, the EU is described as a normative actor motivated by the promotion of universal norms instead of its own interests. Criteria, based on the Normative Power Europe theory, guide the assessment of the normativity of the EU’s climate policy towards Africa. According to the applied criteria, both the objectives and the means of climate policy should be normative in order for the policy to be considered normative. In its relations with Africa, EU climate policy is not purely normative but a combination of norm diffusion and pursuit of self-interest. EU seeks to secure its energy supplies and European security and increase the opportunities of European industry in Africa. In terms of means, the asymmetric balance of power is a problem for normativity. It makes the EU’s persuasion towards Africa and using the development aid as means of norm diffusion seem like coercion. Thus, the EU climate policy is not always normative. Depending on the context, it is either normative, imperialist or status quo policy.
  • Kankaanpää, Liisa (2023)
    This master’s thesis focuses on the relationship immigrants have with urban nature and the possible link between spending time in nature and integration. The research questions focus on the experiences immigrants have with urban nature, the meaning and value they give to it as well as its possible effects on their integration. Five individual, semi-structured interviews were conducted in order to answer these questions. The transcribed interview material was analysed using a thematic analysis method. The results of this analysis showed six themes, divided into two domains: reasons for spending time in nature and factors affecting nature behaviour. Interviews demonstrated nature’s positive effects on overall well-being and thus also integration, even though interviewees were not themselves very aware of this connection. However, all described that their ways of spending time in nature had changed between their home country and Finland. Many also demonstrated a “nature-lover” identity: nature had been important to them already from early childhood. Nature’s role in immigrant integration has been proved in various studies, yet its applications remain limited, and the existing knowledge is fragmented. Few studies concentrate on the ways individuals can take advantage of nature-related activities in their own integration. This thesis shows that spending time in nature and doing different nature-related activities can prove useful in integration but seems to relate more to the person’s individual identity rather than their ethnicity or immigration status.
  • Rautanen, Pauliina Eeva Maria (2021)
    Growth Differentiation Factor-15 (GDF15) is a neurotrophic factor associated with anorexia and weight loss. It is elevated in obesity and various diseases. It signals by forming a tripartite complex with the coreceptor Glial cell line-derived neurotrophic factor (GDNF) family receptor alpha-like (GFRAL) and the receptor Rearranged during transfection (RET). Targeting this pathway has therapeutic potential for the treatment of obesity and anorexia-cachexia syndrome, but many aspects are still unclear. What is the affinity of binding between these proteins? Does GDF15 induce dose- and time-dependent RET phosphorylation and activate intracellular signaling pathways, and are there differences between GDF15 and GDNF signaling, as the different bend angles of their complexes suggest? Can soluble GDF15-GFRAL mediate the effects of GDF15 outside of the brainstem, and what is the function of the short cytoplasmic domain of GFRAL? Furthermore, how well is the pathway evolutionally conserved between species? Binding affinities were assessed with microscale thermophoresis, whereas RET phosphorylation and intracellular signaling assays were performed utilizing immunoprecipitation and western blotting. GFRAL-RET binding is low-affinity (350 nM ± 223) similarly to GFRα1-RET binding (GDNF family receptor alpha-1), whereas GDF15-RET binding without GFRAL does not occur. GDF15 appears to compete for binding to GFRAL or RET, differing from GDNF mechanisms, but noise in the data may have affected the results. The data provide ideas about the ligand-receptor complex formation. Furthermore, RET phosphorylation by GDF15 is dose- and time-dependent. Firstly, the strongest RET and ERK activation occur at GDF15 concentrations typical of disease states. Secondly, RET activation by GDF15 is rapid and sustained like by GDNF activation, whereas ERK activation by GDF15 is rapid and much more transient than by GDNF. Thirdly, AKT activation by GDF15 is much weaker than by GDNF. The differences may be caused by different conformations of binding surfaces for adaptor proteins being available on RET because the bend angles of the complexes are different. Moreover, soluble GDF15-GFRAL does not activate RET, although soluble GDNF-GFRα1 does. Also, the short cytoplasmic domain of GFRAL is not necessary for activating AKT and ERK pathways, but may be needed to activate RET. Furthermore, GDF15 from cynomolgus monkey, but not rat or mouse, activates RET with human GFRAL, indicating sequence similarity in the active site of GDF15. In conclusion, novel aspects of GDF15 signaling and differences between GDF15 and GDNF signaling were discovered.
  • Mehta, Saumya (2020)
    Type 2 diabetes mellitus (T2DM) has been shown to be associated with hyperglycemia, insulin resistance, hyperinsulinemia and impaired insulin secretion from pancreatic β-cells leading to micro- and macro-vascular complications including multiorgan failures. At the cellular level, the mechanism of insulin resistance is associated with complex PI3K-Akt mediated insulin signaling pathway. Moreover, lipid phosphatase SHIP2 (Src homology 2 domain containing inositol 5-phosphatase 2) plays a vital role as a negative regulator of the insulin signaling pathway downstream of PI3K by hydrolyzing phosphatidylinositol- 3,4,5-trisphosphate (PIP3) into phosphatidylinositol- 3,4- biphosphate (PIP2). Scientific reports have shown that inhibition of SHIP2 activity might improve Akt phosphorylation and thus PI3K-Akt mediated insulin signaling pathway. Considering this, I am interested in the SHIP2 inhibitors with drug like properties such as improved solubility, pharmacokinetic and bioavailability properties with little to no contraindications. In the present thesis, I have attempted to detect indirectly the capacity of 8 novel small molecule SHIP2 inhibitors, #160, #161, #162, #163, #167B, #170A, #171, #172 for their ability to phosphorylate Akt kinase in L6 myotubes using immunoblotting as a tool and compared data using graphical representation to pick up the best candidate. Two inhibitors, #163 and #170A were further chosen for alamarBlue® cytotoxicity assay. Treatment with #163 did not display direct cytotoxic effects on the myotubes. The viability of myotubes was not affected at low concentrations of #170A, but it started to reduce at concentrations >200 µM. In my study, I came up with #163 and #170A as the best lead candidates for further analysis. In future, more trials need to be performed with these inhibitors. Moreover, there are several other novel small molecule SHIP2 inhibitors identified from chemical library that need to be tested. Briefly, in this thesis, I have first time reported 8 novel small molecule SHIP2 inhibitors which could be a significant step in the discovery of new T2DM drugs for more efficient, cost effective and safe treatment of the disease with least contraindications.
  • Salumäe, Astrid (2020)
    In biotechnological protein production and metabolic engineering, regulating the expression of genes is essential. For this, expression systems composed of promoters, terminators and transcription factors are essential. So far, majority of these systems use native promoters and transcription factors. That however rises two problems: 1) these systems usually work in only a set of closely related species, 2) native regulatory components can cause unintended expression levels due to the complexity of cellular regulation. Recently, a synthetic expression system (SES) was established for a wide range of fungal species. The transcription factor used in this system comprises an activation domain that originates from a virus. However, in the field of biotechnology and especially food industry, viral DNA constructs are not favorable because of customer concerns. In this paper, plant-derived activation domains were screened in Trichoderma reesei and Pichia pastoris using mCherry as a target gene for measuring the expression levels. The best expression systems were also tested for protein production in T. reesei and P. pastoris. We tested the production of two different proteins – a bacterial xylanase and a phytase. Two of the novel activation domains provided similar expression levels to the viral activation domain in both fungi. In addition, we developed optimized expression systems for an unconventional yeast from Zygosaccharomyces spp. using the novel transcription factors. The best SES version was used for secretion signal sequence screening for xylanase protein production. To further improve the use of T. reesei as a production host, the CRISPR-Cas9 system with the Cas9 D10A nickase version was tested for transformation of T. reesei. Here, we demonstrated the genomic integration and expression of Cas9 D10A nickase in T. reesei using the SES system with the novel plant-derived activation domain. Furthermore, we successfully transformed the T. reesei Cas9 D10A nickase expressing strain using only guide-RNAs and a donor DNA.
  • Ilona, Kortelahti (2024)
    Nuclei isolation is a method used e.g. as a part of chromatin structure research. DNA structure can be examined in its 3D form from isolated nuclei because DNA is still wrapped around the histone proteins. Examining the chromatin structure can offer information e.g. about gene expression and how it is regulated. Isolating nuclei from plant cells demand more optimization compared to animal cells because of the cell wall, chloroplasts and secondary metabolites. The presence of organellar DNA can hamper the later DNA analysis. Secondary metabolites can hinder the actual isolation process. Finding the suitable isolation protocol for species of interest may need careful optimization of different aspects. Different species can differ from each other based on the structural and biochemical characteristics and because of this the same protocol may not ensure as good results for them. Different tissue types of the same species may have also differences in their biochemical and structural characteristics. In this thesis work, three different isolation protocols were used for three plant species; Pinus sylvestris, Betula pendula and Arabidopsis thaliana. The purpose of the work was to compare the results from each nuclei isolation protocol. Optimization of isolation protocol for P. sylvestris and B. pendula would help the isolation process for later research. Thesis work was done to get guidance for this optimization. Samples handled with different protocols were different from each other based on the sample concentration (particles/mL) and the average size of isolated particles. Chloroplast contamination was tested with chloroplast specific primers with PCR. None of the samples were free from chloroplasts.
  • Heikkinen, Aino (2018)
    Chronic psychosocial stress is a major risk factor for anxiety disorders, but the molecular background is still poorly known. Chronic social defeat stress (CSDS) is a mouse model simulating the psychosocial stress that humans face in their life. In CSDS, the examined mice are confronted by an aggressor mouse daily for 10 days, leading to defeat behavior and predisposing to anxiety-like symptoms. Some individuals develop these symptoms (susceptible) whereas others do not (resilient). Chronic stress has been shown to alter myelin-related gene transcription and myelin microstructure. Myelin is a membranous component around axons increasing the velocity of action potentials, and it is produced by oligodendrocytes (OLs). In this study, I investigated if CSDS affects the number of OLs or the size of the myelinated area (estimating the amount of myelin) in two inbred mouse strains that differ in their innate level of anxiety: the non-anxious C57BL/6NCrl (B6) and anxious DBA/2NCrl (D2). I studied three brain regions previously associated with anxiety: the medial prefrontal cortex (mPFC), bed nucleus of stria terminalis (BNST) and ventral hippocampus (vHP). The mice used in this study were previously exposed to CSDS and divided into resilient or susceptible phenotypes, and their brains were collected together with control mice. I performed two immunohistochemical staining experiments to calculate the number of OLs and to measure the myelinated area. I used anti-CNPase for OL cell counts and BlackGold II to stain myelin. I manually calculated the number of OLs using CNPase and cell morphology as markers. I built a macro to measure the BlackGold II stained myelinated area. I also measured the thickness of the corpus callosum (CC, major white matter tract) using the CNPase stained images to examine if the thickness is affected by CSDS. I observed a strain and region-specific effect of chronic stress in the BNST; B6 resilient mice had more OLs than susceptible mice whereas no differences were seen in the D2 strain, or other B6 brain regions. The size of the myelinated area did not differ between the phenotypes in either strain. Moreover, there was no significant correlation between the myelinated area and OL cell number. The CC thickness did not differ between the phenotypes. My findings indicate that myelin and OLs are affected by stress in a region specific manner and possibly contribute to the stress-resilient behavior. The response is genetic background-dependent, as I saw differences in B6 mice but not in D2 mice. Because CC thickness did not differ between the phenotypes, we suggest that CSDS does not induce extensive white matter atrophy in the mice brain. The mechanism underlying this dynamic myelin plasticity during stress requires more investigation, but this study provides evidence that alterations in OLs associate with chronic stress.