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(2020)Jäkälät ovat sieniosakkaan ja yhteyttävän levän muodostamia symbiooseja, joista suurin osa elää maaekosysteemeissä ympäri maapalloa. Jäkälät toimivat ekosysteemeissä tärkeinä indikaattorilajeina, sillä ne ovat usein hyvin herkkiä elinympäristössä tapahtuville muutoksille, esimerkiksi ilmanlaadun huononemiselle. Sticta-suvun syanojäkäliä on tähän mennessä kuvattu noin 200 lajia erityisesti subtrooppisilta ja trooppisilta alueilta. Todellisuudessa lajimäärän arvioidaan olevan paljon suurempi. Afrikan jäkälistä tiedetään vielä suhteellisen vähän, ja tietomme Itä-Afrikan Sticta-lajeista pohjautuvat pääasiassa 1980-luvulla tehtyyn tutkimukseen. Tässä tutkimuksessa tavoitteenani oli tuottaa DNA- analyysiin perustuva selvitys Sticta-suvusta Kenian Taitavuorilla. Tutkimuksessa selvitin myös Sticta-lajien symbioottisten syanobakteerigenotyyppien levinneisyyttä Taitavuorten eri metsäsaarekkeissa ja eri Sticta-lajeissa. Tutkimukseni aineistona oli 176 jäkälänäytettä, jotka ovat kerätty Taitavuorten alueelta sekä Elgonvuoren rinteeltä Länsi-Keniasta Jouko Rikkisen ja Ulla Kaasalaisen toimesta vuosina 2009- 2017. Alustava lajinmääritys morfologian perusteella tapahtui mikroskopoimalla. Neljänkymmenenkahdeksan näytteen tarkempi lajinmääritys tehtiin DNA-menetelmin, selvittämällä jokaisesta näytteestä sienen sekä syanobakteerin genotyyppi. DNA-eristyksen, PCR:n sekä elektroforeesin tein Helsingin luonnontieteellisen museon laboratoriossa kesällä 2018. DNA- sekvensointi tehtiin Sanger-menetelmällä Saksassa GATC Biotech-yrityksen toimesta. Laboratoriotöiden tuloksena sain sieniosakkaan DNA-sekvenssin kaikkiaan 48 jäkälänäytteistä. Sekvenssien perustella 46 näytettä voitiin määrittää ennestään tunnetuiksi Sticta-lajeiksi, ja kaksi näytettä osoittautui Sticta pseudosylvatica -lajille sukua olevaksi, toistaiseksi kuvaamattomaksi lajiksi. Näytteistä löytyi kaikkiaan 21 erilaista syanobakteerigenotyyppiä. Eri metsäsaarekkeista kerättyjen näytteiden syanobakteerikoostumus ei näyttänyt poikkeavan toisistaan, mutta Sticta- lajien syanobakteerikannat poikkesivat toisistaan.
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(2013)The bioluminescent and toxin-producing dinoflagellate Alexandrium ostenfeldii forms dense blooms in coastal areas of the Baltic Sea. Bioluminescence, light production by an organism through a chemical reaction, is a nocturnal, rhythmic phenomenon in surface algae. In this study, the bioluminescence pattern and rhythm of A. ostenfeldii was under investigation. Procedures for continuous bioluminescence measurements, to support dedicated environmental monitoring of toxic dinoflagellate blooms, were developed. The study consisted mainly of laboratory experiments. Semi-continuous field measurements were included for comparison. In the laboratory, the light production of monocultures of A. ostenfeldii was measured with a spectroluminometer or bathyphotometer, continuously during the night, or for several consecutive days. The method to stimulate bioluminescence was varied, as well as the recovery period of the cells after stimulation. Light regimes during growth and pre-measurement adaptation were also taken into account. The experiments confirm that bioluminescence in A. ostenfeldii follows a circadian pattern and can be stimulated with the chosen methods. Bioluminescence could also be stimulated after culturing in continuous light. Measurement parameters for rhythm experiments (stimulation frequency and recovery period), were optimised. Multi-day experiments in complete darkness suggested that sufficient energy was available to maintain bioluminescent response during one night, although an endogenous rhythm remained present. These experiments gave insight to the phenomenon of bioluminescence regulation in A. ostenfeldii, but also gave rise to new questions. Some repeated measurements resulted in very low bioluminescence intensity, without an obvious reason. The light regime is not the only factor controlling bioluminescence. The interplay between bioluminescence and the growth and condition of the cultures is of interest.
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(2014)Havsekosystemen runt om i världen lider av antropogen inverkan såsom näringsutsläpp och utfiske. Speciellt utfiske av högre trofiska nivåer dvs. stora rovfiskar, anses ha ändrat dynamiken i flera näringsvävar. Ändringarna har lett till kraftiga trofiska kaskader som ökat eller minskat primärproduktionen speciellt vid kustliga vattenområden. Speciellt mesopredatorer har ökat i antal, och i Östersjön är storspiggen (Gasterosteus aculeatus) en art som börjat dominera samhället. Storspiggen konsumerar växtavbetare av trådalger, och kan därmed ha en effekt på trådalgstillväxten i Östersjön. Undersökningens syfte är att granska vilken roll storspiggens predation har i trådalgsbältet, och hur ändringarna syns i näringsväven. Undersökningen bestod av ett mesokosmexperiment och en fältundersökning vid Tvärminne zoologiska station. Mesokosmexperimentet bestod av två behandlingar: 10 mesokosm med två trofinivåer (utan storspigg), och 10 mesokosmer med tre trofinivåer (med storspigg). Trofinivåerna bestod av trådalger (Cladophora sp.), märlkräftor (Gammarus sp.) och storspigg. Experimentet pågick 4 veckor, vartefter mesokosmerna tömdes och innehållet analyserades. Med en veckas mellanrum gjordes fältbesök till den närbelägna ön Långskär, för trådalgsprovtagning, observation av storspiggstäthet och magsäcksanalysering av fångade storspiggar. Trådalgsproverna analyserades under mikroskop. Fältundersökningens resultat visade att mängden storspiggshanar och fångade storspiggar minskade längs med säsongen, medan trådalgsbiomassan ökade. Antalet vuxna storspiggar korrelerade negativt med märlkräftor. Mesokosmexperimentets resultat visade att mesokosmen med storspigg hade i medeltal högre trådalgs-biomassa (24%), högre epifytmängder (72%), färre märlkräftor (79%) och lägre färgintensitet än mesokosmerna utan storspigg. I Mesokosmerna utan storspigg hade trådalgsbiomassan inte ökat nämnvärt, men trådalgen var tydligt grönare i färg och saknade epifyter. Av resultaten framgår att storspiggen påverkar primärproduktionen i ekosystemet, genom en trofisk kaskad, då växtavbetarna regleras kraftigt. Primärproduktionen ökar mest i form av epifyter och mikroalger, vilket leder till att trådalgen kvävs och börjar föråldras. Trådalgen och växtavbetarna har därmed ett mutualistiskt förhållande. För att minska mängden skadliga algblomningar i Östersjön, borde näringsvävarnas stabilitet och mångfald tas i beaktande vid fiskeriförvaltningen för att effektivera Östersjöns rehabilitering.
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(2022)Sustainable consumption has become a widely debated topic in academic discussions, politics, the media, and consumer culture. The objective of this thesis was to identify the stories that are told about overconsumption and how responsibilities for the issue are distributed to different actors in these stories. Stories, in which events logically unfold and actors are positioned into different roles have a key role in the articulation of understandings of phenomena. 13 online news articles and two editorials published in three Finnish news media and the related news discussion forums were chosen as an empirical example of public discussion that shapes and reflects common perceptions on the issue. The news articles and editorials include references to the Earth Overshoot Day, limiting the context of the thesis to overconsumption that is defined based on the limits of the planet’s biocapacity. With the help of a qualitative narrative analysis, four storylines were constructed. These storylines are overconsumption by overpopulation, greed and impossible endless growth; one world, shared challenge, and technology as the problem and the solution. The most frequently mentioned actors across the storylines are citizens, developing and wealthy nations, decision-makers and politicians, businesses, and wealthy elite. Besides reflecting both academic discussions and previous literature on narratives about sustainable consumption, the presence of population dynamics and the conflict between socio-economic development and environmental well-being was notable in the analyzed discussions. The incomplete narrative structures, missing roles, and diverse elements included in the storylines reflect the complexity of the issue and the struggles related to articulating a coherent story with a sufficient solution and actors capable of solving the issue. To clarify the discussion on the topic, it is suggested that the distribution of the responsibilities and opportunities to improve the situation amongst actors should be addressed in the communication on sustainable consumption and the Earth Overshoot Day.
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(2022)Faculty: Faculty of Biological and Environmental Sciences Degree programme: Master’s Programme in Neuroscience Study track: Neuroscience Author: Emma-Helka Erkkilä Title: The brain physiology of stress and the effects of burnout on executive functions Level: Master’s thesis Month and year: 08/2022 Number of pages: 35 Keywords: executive functions, emotion, cognition, stress, burnout Supervisor or supervisors: Docent Kaisa Hartikainen and Lic.Med. Mia Pihlaja Where deposited: Helsinki University Library Additional information: Abstract: BACKGROUND- Burnout as a result of prolonged and excessive stress may impair higher order cognitive functions of the brain such as executive functions and their efficiency. This Master's thesis examines the effects of chronic stress on the brain, more specifically the effects of burnout on executive functions. The aim of this study was to specifically research the effects of burnout on executive and emotional functions and their interaction. The research was conducted at the Behavioral Neurology Research Unit, Tampere University Hospital as part of Sustainable Brain Health project funded by the European Social Fund. MATERIAL AND METHODS- 54 voluntary examinees of whom 51 were analyzed. The examinees were divided into two groups based on BBI-15 survey (27 suffering from burnout and 24 control subjects without burnout). The examinees performed a computer-based Executive reaction time (RT) test, during which a 64-channel electroencephalogram (EEG) was recorded. In additions all examinees received alternating transcutaneous vagus nerve stimulation (tVNS) and placebo stimulation. From the Executive RT test, we obtained objective measures reflecting the efficiency of executive functions (RT and total errors) and specific executive functions such as working memory, inhibition and attention. Additionally, the emotional stimulus included in the test enabled the assessment of the emotional functions and the interaction between emotional and executive functions. The EEG and tVNS results were not in the scope of this master’s thesis, and they will be reported later on. RESULTS- The results of this thesis are preliminary. Distinct positive correlation was observed between burnout assessment based on the BBI-15 survey and the results of the BRIEF-A self-report which measures the subjective experience of challenges in executive functions in daily life. There was no statistically significant (p<0.05) difference between the groups in RTs or errors made in the Executive function RT test. Instead, the groups differed on how the threatening emotional stimulus affected the accuracy of responses. Subjects suffering from burnout made less errors with a threatening emotional stimulus compared to a neutral stimulus and vice versa the control subjects made more errors with the threatening emotional stimulus compared to neutral. This difference was statistically significant (p=0,025). DISCUSSION- Challenges experienced in everyday executive functions were linked with burnout. However, RTs and errors in the Executive reaction time test did not correlate with the severity of the burnout nor were the self-evaluated problems in executive functions depicted in the test performance. Instead, the subjects suffering from burnout differed from the control group in how the threatening stimulus affected the accuracy of responses in the test. It is possible that the subjects suffering from burnout benefit from the increase in arousal caused by the threatening emotional stimulus which was shown as improved accuracy of responses when there was a threatening stimulus, whereas the control group's accuracy of responses was disrupted by the threatening stimulus. We speculate that if the control group’s baseline level of arousal was optimal then the threatening emotional stimulus may have increased arousal to suboptimal level causing decrease in performance. Subjectively experienced challenges in executive functions and objective changes in the interaction between emotions and the executive functions were observed in the study. In conclusion, burnout causes changes in executive functions.
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(2023)Urbanisation is rapidly increasing, along with the use of artificial lighting, which poses a growing threat to wildlife, especially nocturnal fauna. Bats are nocturnal mammals that prey on light-sensitive insects, making them particularly vulnerable to the effects of artificial light sources. Responses to artificial lights vary among bat species, with some being strongly repelled while others appear to benefit from them. However, little attention has been given to the impact of light pollution on bats in northerly latitudes, where bright summer nights may influence the effects of artificial light on these animals. In my thesis I compared the presence of bats in artificially illuminated and unilluminated areas in urban parks in Southern Finland. To see the effect of bright nights in the early summer I collected acoustic data during two time periods: bright early summer (June), and dark late summer (August). My aim was to determine if different bat species respond differently to artificial light, if lamp type affects their response, and how natural light influences their activity patterns. I found that northern bats (E. nilssonii) were drawn to street lights in both early and late summer, and they seemed to prefer HPS (high-pressure sodium) lamps to LED (light emitting diode) lamps. Conversely, more light shy bats from the genus Myotis strictly avoided street lamps at all times. The strongest effect of natural light on bats was observed on their activity patterns: the timing of peak activity shifted considerably along with changes in natural light conditions. My results indicate possible changes in the responses of nocturnal wildlife to the changes in spectral composition of illumination along with increasing popularity of LEDs. The significant differences in the responses of different bat taxa to illumination highlight the importance of conservation of dark spaces and times.
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(2022)COVID-19 pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has thus far claimed over six million lives. Vaccines against SARS-CoV-2 have successfully mitigated severe disease and eased the burden on healthcare systems. Neutralizing antibodies play crucial roles both in vaccine derived immunity, and as drugs widely utilized in monoclonal antibody therapy. Neutralizing antibodies primarily target the spike protein, where most of the neutralizing epitopes are located in the receptor binding domain (RBD). Elucidating the sites of vulnerability to neutralization on SARS-CoV-2 can facilitate the development of therapeutics. 7A12 is a newly-discovered IgG antigen-binding fragment (Fab) isolated from a COVID-19 patient in Finland that can neutralize SARS-CoV-2 by targeting the spike protein. In this thesis, a complex of the Fab 7A12 with SARS-CoV-2 spike ectodomain trimer was studied using cryogenic electron microscopy (cryo-EM) single-particle analysis to elucidate the epitope of 7A12 and to gain insight into the neutralization mechanism of 7A12. Cryo-EM data of the complex revealed that Fab 7A12 can bind to both “open” and “closed” conformations of RBD. Rigid-body fitting of the spike trimer and Fab 7A12 models into the cryo-EM density indicates that 7A12 recognizes an epitope in the RBD which is mainly located outside the ACE2 binding site. Together, these results suggest that the 7A12 epitope belongs to class III of SARS-CoV-2 neutralizing epitopes located in the RBD, indicating that 7A12 could neutralize by sterically hindering ACE2 and by preventing the adjacent RBD from changing to ”up” conformation. Furthermore, our results revealed an overlap of 7A12 epitope with the putative binding site of heparan sulfate, a host factor of SARS-CoV-2 infection, which might contribute to neutralization. 7A12-RBD interface mapping delineated the residues comprising the epitope, which do not include mutants found in Beta, Gamma, and Delta variants, while four mutants were found in Omicron within the epitope indicating that 7A12 is likely to neutralize Beta, Gamma, and Delta variants of concern.
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(1998)Cells in tissues have only three serious options in life; they can grow and divide, remain static, or die by apoptosis. Upon growth factor stimulation a cell enters the so called cell cycle which will eventually lead to the division of the cell. Cell cycle can be divided into four phases; G1, S, G2 and M. The current model of the cell cycle control holds that the transitions between different cell cycle states are regulated by cyclin dependent kinases (CDK) with their activator subunits, the cyclins. CDK regulation can be separated into four distinct mechanisms, one of which being phosphorylation on the so called T-loop leading to complete activation. This phosphorylating activity is mediated by apparently a single enzymatic activity termed the CDK activating kinase, CAK. CAK activity was originally isolated as a biochemical purification extract and the enzyme was surprisingly noticed to be structurally related to CDKs. Since a novel cyclin was identified to be associated to it, the enzyme exercising CAK activity was named CDK7 and the cyclin was designated cyclin H. An entirely new perspective on CDK7 function was opened when CDK7 was identified as a subunit of transcription factor IIH (TFIIH) and shown to phosphorylate the carboxy-terminal domain (CTD) of RNA polymerase II (RNAPII). CDK7 has also been suggested to be involved in irradiation sensitivity pathways and nucleotide excision repair functions. To elucidate the intriguing in vivo role of CDK7, proteins interacting with CDK7 were screened for using the yeast two-hybrid method as part of previous studies of the laboratory. The results showed that 15 out of 144 (10,4%) positive clones were identified to encode a peptide sequence of a protein previously known as the inhibitor/interactor of protein kinase C (PKCI). These yeast colonies had an unexpected phenotype; contradictory to a dark blue color of the colonies, indicating strong interaction, the size of the PKCI colonies was small compared to others, indicating a possible growth inhibition effect. Several DNA open reading frames (ORF) coding for proteins related to human PKCI have been identified in a broad range of species representing mammalian, plant, fungal and bacterial kingdoms, all these forming a HIT (conserved triad of histidines) protein family. Another human member, part of this now super family, named FHIT (fragile triad of histidines) was identified with a dinucleoside 5’,5’’’-P1,P3-triphosphate hydrolase activity. These molecules; substrates of FHIT and related enzymes have been proposed to have various intracellular functions, including signalling stress responses. The aim of this study was to extend the investigation of the interaction between CDK7 and PKCI observed in yeast two-hybrid by means of several genetic and biochemical approaches to determine if this observed interaction and growth phenotype has any physiological significance. Investigations included performing yeast two-hybrid screening for PKCI, developing yeast three-hybrid system and carrying out growth rate assays for yeast liquid cultures. These studies also included performing biochemical purifications of over-expressed proteins, immunoprecipitations, western blot analysis and kinase activity assays. Protein extracts originated from transformed yeast cells, transfected mammalian cells or from in vitro transcription and translation reactions. On basis of growth rate assays it can be concluded that PKCI has an inhibitory growth effect in yeast. The preliminary finding of a specific PKCI-CDK7 interaction in yeast two-hybrid, however could not be conclusively verified by the other methods that were used in this study. Studies of PKCI characterisation also included examination of the subcellular localisation of PKCI in mammalian cells by immunofluorescence labelling of HA-PKCI. Results showed PKCI to localize both in the nucleus and in the cytoplasm. Also, studies to elucidate the function of PKCI were performed; whether it possesses enzymatic activity related to that of FHIT. By NMR spectroscopy using bacterially produced GST-PKCI, hydrolase activity towards ADP was indeed observed. Future studies will include elucidation of possible links between growth inhibition and hydrolase activity, in the form of stress signalling functions. The main focus of our future studies will be the generation of mice with targeted PKCI alleles offering powerful means to reveal the function of PKCI through observing phenotypes and through detailed analysis of these mice harbouring wild type, hypomorphic or null alleles.
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(2021)Bartonella species are facultative intracellular bacteria causing variety of diseases in humans and also infects endothelial cells and erythrocytes. Some Bartonella species utilize VirB/VirD4-type IV secretion system (T4SS) in order to secret Bartonella effector protein A (BepA) which infects endothelial host cells by inhibiting the apoptosis. But the enterotoxin homolog in Bartonella gene A (EhbA) and the enterotoxin homolog in Bartonella gene B (EhbB) are found in the non-BepA Bartonella strains. In my Master’s thesis, I study the host cell binding activity and identify host cell surface receptor of EhbB in Bartonella. In my thesis, the cell adhesion of multimeric B proteins of enterotoxin homologue in Bartonella (Ehb) have been analyzed with cell adhesion assay using HEK293T, HeLa 229, Ea.hy926, and CHO-K1 cells. The assay was conducted with EhbB1 and EhbB 1-1C proteins from Bartonella Bovis strain Bermond and Bartonella strain spp 1-1C and the experiment indicated the cell adhesion activity of both EhbB proteins compared to the controls used in the experiment. Moreover, the binding activity of EhbB1 with Ea.hy926 was studied at several incubation time points, such as; 30 min, 2 hours, 4 hours, 6 hours, and 8 hours. Several incubation period of EhbB1 and EhbB 1-1C with Ea.hy926 cells did not enhance cell surface adhesion because the same absorbance compared to controls. The interaction of EhbB1 with cell membrane HEK293T was studied by using western blot on cell membrane preparation from Ea.hy926 cells which was used to identify possible protein receptor of EhbB1. The experiment suggests that EbB1 is binding to receptors present on the cell membrane of HEK293T which could be protein. The cell adhesion activity of HEK293T cell membrane with EhbB1 was analyzed by inhibition assay. This experiment indicated that EhbB1 protein attached to cell surface receptors present on the HEK29T cell membrane, which inhibited EhbB1 protein to attach to Ea.hy926 cells. This also indicate that the cell surface receptor for EhbB1 could be protein but requires further study.
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(2019)Tiivistelmä – Referat – Abstract Cardiomyocytes derived from human induced pluripotent stem cells (hiPSCs) provide a good model to study their function in human context. The hiPSC technology allows to create patient-specific cell lines. The cell lines can further be differentiated into any cell type retaining the same genetic information as the donor. Heart diseases such as Long QT syndrome (LQTS) and Non-compaction cardiomyopathy are caused due to mutations in ion channels in cardiac cells. The genetic abnormalities in these channels can cause life threatening arrhythmias. However, the diseases remain undiagnosed until later stage of the disease and the first sign could be sudden cardiac death. Hence, understanding the disease mechanism at a cellular level is crucial. The aim of the thesis is to study the functionality of cardiomyocytes from patient specific cells to analyse if the clinical representation of the diseases can be seen at the cellular level. An additional aim is to compare and study the Ca2+ transients in patient-derived and control cells. One way to study the functionality of cardiomyocytes is by Ca2+ imaging. The method involves live cell imaging of differentiated cardiomyocytes using fluorescent dyes (Fluo4 AM and Cal520). The Ca2+ transients of diseases such as LQTS and non-compaction cardiomyopathy are recorded and further analysed by Clampfit software. The main findings of this study include a) different Ca2+ dyes (Cal520 and Fluo4) had different profiles in control cardiomyocytes b) a significantly different profiles were observed between the SCN5A-mutant and control cardiomyocytes c) the effect of adrenaline was most significant at low doses and when exposed for a short time; prolonged exposure to adrenaline leads to adrenaline receptor desensitization. Moreover, different types of arrhythmias have been detected in cell lines such as oscillations, plateau abnormality, multiple peaks etc. In conclusion, detection of Ca2+ transients may be an indicator of heart diseases due to genetic mutations which will further help in taking preventive measures.
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(2019)Twisted-winged parasitoids (Insecta: Strepsiptera) are parasites of other insects, which are characterized by complex life cycles and extreme sexual dimorphism. They have three endoparasitic larval stages. In most Strepsiptera only the motile first instar larvae and adult males are free living whereas the adult females are endoparasites during their entire life. The winged males slightly resemble flies, while females are neotenic. Around 630 extant Strepsiptera species are known but this is probably an underestimation since many species are cryptic. The genus Stylops, parasitoids of mining bees of genus Andrena, is one of the biggest genera of Strepsiptera. Until recently it was thought that only one species, Stylops melittae, occurs in Europe. Studies using DNA-methods revealed that it is in fact a species complex of 30 species. This study investigated which of these species occur in Finland. In addition, it was examined if the female morphology of the species could be used in species identification, since males are rarely found. Andrena host specimens were examined from three major entomological collections and the collecting data of the observed Stylops was recorded to a database. Suitable specimens were DNA barcoded and the acquired DNA barcodes were compered for the ones in databases (BOLD, GenBank). The females were separated from their hosts and photographed for the morphological examination using different imaging methods (focus stacking, SEM). Based on this study there are five species of Stylops in Finland instead of one as previously thought: S. thwaitesi, S. ater, S. japonicus, S. nevinsoni and S. spreta. In addition, there is one species, which is most likely undescribed. All females of these species can be identified based on their morphology. The results include summaries of each species containing information about their morphology, ecology, distribution and abundance. This study gives valuable new information about the twisted-winged parasitoids in Finland. The occurrence of the genus Stylops in Finland based on current taxonomy was examined for the first time. The study gave novel information about the distributions of Stylops-species. Deviating from previous information Stylops japonicus is also found in Europe. Furthermore, the study revealed new information about the host-parasite relationships of the species. Many of the Andrena host species had not been associated with certain Stylops species before. There has not been research focusing on Strepsiptera in Finland for a long time. The material collected for this study works as a good foundation for the possible future studies in Finland. The results were used in the 2019 Red List assessment and two of the Stylops species were in the Red List of threatened species.
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(2021)Pohjoisilla soilla on suuri merkitys globaaleissa biogeokemiallisissa kierroissa niiden kerrostaman ja vapauttaman hiilen vaikutuksesta. Ilmastollisten tekijöiden on todettu olevan yhteydessä suon hydrologisiin vaihteluihin, kuten kuivumiseen, vettymiseen, routaantumiseen tai roudan sulamiseen. Muutokset suon hydrologiassa ovat menneisyydessä heijastuneet vuorovaikutteisesti soiden kasvillisuuteen ja niiden rooliin maailmanlaajuisesti merkittävinä hiilinieluina. Pohjoisten ikiroutasoiden ainutlaatuinen ja rikas habitaatti on vaarantunut nykyisen ilmaston lämpenemisen myötä. Maisterintutkielmani tavoitteena on arvioida mahdollisia ilmaston lämpenemisen aiheuttamia vaikutuksia pohjoisiin soihin tutkimalla viimeisten vuosisatojen aikana tapahtuneita muutoksia suokasvillisuudessa. Tutkielmassa selvitin, miten tutkimussuoni kasvillisuus on muuttunut ja millaisia yhteyksiä voidaan havaita eri ilmastovaiheiden merkittävimpiin lämpötilan muutoksiin. Keskityin analysoimaan näitä muutoksia kasvimakrofossiili-analyysin avulla. Näytesarjat ajoitettiin radiometrisin menetelmin. Tulokset osoittivat tutkimussuon käyneen läpi kuivan kasvillisuuden vaiheita sekä ilmastohistorian lämpiminä että kylminä ajanjaksoina. Nykypäivän lämpenemisen aikana eri näytepisteissä on tapahtunut sekä kuivumista että siirtymiä kosteaan suoekosysteemiin ikiroudan sulamisen jälkeisinä ajanjaksoina. Tutkimukseni tulokset auttavat osaltaan ymmärtämään ympäristössä ja ilmastossa tapahtuvien muutosten kompleksista vaikutusta pohjoisiin suoekosysteemeihin. Tutkimuksen perusteella voidaan arvioida nykyisen ilmastonmuutoksen mahdollisia vaikutuksia tutkimussuohon, sekä rinnan muiden tutkimusten kanssa yhteyksiä pohjoisten soiden tulevaisuuden hiilitasapainoon ja suuren mittakaavan biogeokemiallisiin kiertoihin.
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(2019)This thesis aims to find out what are the challenges in the implementation of corporate social responsibility (CSR) strategy in a large labour-intensive company in the service business. Companies have an essential role in sustainable development and they are seen as important actors in spreading awareness of sustainability (Simas et al., 2013). While CSR is a concept that is playing an important part in the modern business world and has been involved in companies’ strategies for years now, there is still a gap between the CSR strategy formulation and implementation (Engert & Baumgartner, 2016). The research presented in this thesis is based on a literature review of CSR strategy implementation and on a single case study in a service business company, SOL Group, with high employee turnover, low wage levels and physical and intense working conditions. The objective of this thesis is to identify potential challenges in the CSR strategy implementation in large companies in service business, and based on the findings, structure hypotheses for further research. The case study data collection included four group interviews with several participants in each, as well as direct observation in the field, and it is supported by documents from the case company and literature. From the literature review, two models were identified: the five levers model by Lacy et al. (2009) and the success factor model by Engert & Baumgartner (2016). These two models were used as theoretical frameworks for analysing the challenges in the successful implementation of CSR strategy in the case company. The main finding was that the major challenge in the successful implementation of CSR strategy is to commit and engage the employees to the strategy implementation. This thesis proposes hypotheses for the future, to continue this research as an attempt to bridge the gap between CSR strategy formulation and implementation. It is hoped that the insight from this thesis helps companies to identify their challenges in the CSR strategy implementation and provides some guidelines on how to proceed if wanting to achieve a full implementation of CSR strategy.
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(2020)Gender and sex are the most common criteria to classify people in our society. Along with legal and national core curriculum changes perceptions of gender and sex and their diversity has changed. This change is also reflected in learning materials. Learning materials play an important role in teaching and in the perceptions that students form about the role of gender and ability of different genders to influence society and professions. Gender inequality for men has been evident according to previous textbook studies. Gender stereotypes are also explicit. In this research the research material are human biology textbooks for secondary students during the past three national core curriculums. The purpose of this research is to examine how the gender, sex and their diversity are represented in human biology textbooks. Temporal variation is also examined. The qualitative content analysis was used as a principal method to analyse the data. Based on that method citations have been collected from textbooks. To compress the collected data the citations have been classified into different classes that explain the differences between sexes. The final classification has been made based on whether the differences between sexes appear in anatomy and physiology or behaviour and whether they are explained by biological or non-biological factors. Besides this, the collected data has been quantified and prototypes of male and female has been compiled. In quantitative analysis the textbooks visual representation and gendered words are also counted and analysed by simple quantitative methods. Based on this study the sex and gender are seen as a biological feature in human biology books. The differences between sexes are mainly affected by hormones whether the difference is in behaviour or anatomy and physiology. Genes also play an important role when differences in anatomy and physiology are explained between sexes. Psychological and cultural factors also explain a lot of differences in behaviour. Feminine characters and words were overrepresented in the textbooks compared to masculine characters. These are the result of the major role of motherhood and pregnancy in biology textbooks. The word mother was also used widely. In older textbooks the gender is represented more in texts and the differences between sexes are brought out more than in later textbooks. The gender stereotypes are also more evident in older textbooks and the stereotypical features are linked more to sexes, like conscientiousness in women and competitiveness in men. The gendered terms like “feminine” or “masculine” are also more present in older textbooks. Gender diversity is more talked about in later books, which is expected, as it is present in the latest national core curriculums. Otherwise the gender diversity is not very visible. Heteronormativity is present in all books, but for example the sexuality is treated more subtly than in older books. The temporal variation can be explained by the social change that is reflected in curriculums and textbooks. The textbooks should provide the most diverse picture possible of gender and its diversity. Therefore, images representing non-stereotypical and heteronormative gender roles should also be selected for books, and gendered expressions should be used deliberately in texts. However, it is important for gender equality that gender is not completely erased from textbooks. In gender-sensitive teaching, it is important that gender differences are not considered the norm, but they are also not hidden, but learn to identify gender stereotypes and their effects on one's own actions. There is no wrong way to be a boy or a girl. This material could be expanded by exploring the gender roles described in the textbooks as well. In addition, the research material could be compared to health information textbooks or other aspects of equality could be considered.
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(2012)The purpose of this master's thesis is to study nature values within the Finnish national Natura 2000 network on state owned land. The six goals of this work were achieved: 1) Areas with most nature values were identified by prioritizing habitats of Natura 2000 directive (92/43/EU) within. Areas with high nature value were usually in very natural state and had good connectivity to other similar places, or they were spots of some very rare nature types. 2) It was found out that data used was suitable for identifying conservation values, 3) find out the suitability of Zonation software in conservation area management and maintenance planning and 4) find out how results will change if conservation status is taken into account. As an addition to these 5) the most considerable areas with high conservation value were identified and 6) "Zonation software in a nutshell" was produced in Finnish to assist Finnish state officials to use the software for conservation purposes. These results will help Metsähallitus (The Finnish Forest and Park Service) - Natural Heritage Service - to target resourcing of habitat management and restoration in and around the areas with most considerable nature values. It is essential to sustain these areas and their values so that their nationwide importance can be maintained into the future. Data used in this study covered areas that were classified as Natura 2000 habitats according to European Union Council Directive 92/43/EEC. Analyses were done by using Zonation software, a tool for spatial conservation prioritization. Data consisted of 68 Natura 2000 habitat types and their state of naturalness and representativeness. Zonation took into account the rarity, quality, importance, threat status, biodiversity value, congruity and connectivity of these habitat types. As a result software produces a map of conservation priorities and associated quantitative information, which facilitate identification of areas with most considerable nature values. These were identified both ocularly and with Zonation software. Analyses were done at two levels: all habitat types together and in subgroups following division to major habitat types, such as coastal environments, inland waters, meadows, alpine habitats, peat lands, rocky areas and forests. Results showed that connectivity increased aggregation of areas with high nature values and weighting spread them. Hierarchical analysis was used to find out how nature values changed when the conservation status of the areas were taken into account. The results of hierarchical analysis show that conservation status changed the results a lot. Difference between main analysis and hierarchical analysis was much greater than when taken into account connectivity of feature weights. Hierarchical comparison revealed that many areas with considerable high nature values areas are not presently strictly protected.
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(2018)For a long time protected areas have been vital in conserving species and biodiversity. But due to climate change it is important to study whether the protected area networks are able to fulfill their goals also in a changing climate. Because of climate change the amount of southern species is increasing. At the same time the number of northern species is declining as are the suitable habitats for them. In order to adapt to changes in the climate, species are forced to shift their distributions poleward and upward. As a result, species communities are changing and some species may be threatened with extinction. It is therefore urgent to study whether the protected areas can alleviate the effects of climate change and whether they are capable to protect biodiversity in a changing climate. The aim of the study was to investigate whether the protected areas in Finland have been able to alleviate the effects of climate change in the bird species communities. The study was based on line transect bird censuses carried out in 182 protected areas during the years 1980–1999 and 2000–2015. Community temperature index (CTI) was used to study bird communities’ response to temperature change. Thus, CTI is used as a climate change indicator. CTI is based on the average temperature of the species range. A higher CTI value therefore indicates that a higher proportion of birds in the community are warm-dwelling species whereas the low CTI value indicates the opposite. The aim was to find out how the size of the protected area, connectivity between the protected areas and the type of habitat had affected the change of CTI between research periods. Protected areas were divided into three groups based on their location: northern, central and southern parts. 14 models were built in each part, ranked according to their AIC values. Linear regression analysis was used as the analytical method. During the research period, CTI had risen in 155 protected areas indicating a change in the direction of warmer bird communities. However, we found out that certain features of protected areas were able to alleviate the effects of climate change. Better connectivity decreased the changes in bird communities in the northern and central parts. But in the southern parts a similar effect was not found, possibly due to the smaller size of the protected areas and the lower degree of connectivity. The larger size of the protected area was supposed to reduce the changes in CTI but the results did not support this hypothesis. In all parts open habitats were more effective in alleviating the effects of climate change than the forest habitats. On the basis of the results, increasing the connectivity between protected areas could potentially be advantageous for the species suffering from climate change.
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(2015)Ympäristön- ja luonnonsuojelu Suomessa on muuttunut merkittävästi sotien jälkeen. Puhtaasti luonnontuntemukseen ja harrastuneisuuteen pohjaavan luonnonsuojelun rinnalle on kehittynyt 1960- ja 1970-lukujen vaihteessa politisoitunut ja institutionalisoitunut ympäristönsuojelu. Vielä tuolloin ympäristön muutokset koettiin erillisinä ongelmina, kuten ilman saastumisena, elintarvikkeiden myrkkypitoisuuksina ja maiseman pilaantumisena, mutta yksittäisistä ongelmista alkoi kehittyä laajempi kokonaisuus eli ympäristökysymys. Ympäristökysymys käsittää negatiivisesti koettujen ympäristön muutosten tiedostamisen, problematisoinnin, hallinnan ja politiikat. Vaikka ympäristökysymys muodostui ja ympäristöongelmat tunnistettiin yhteiskunnallisiksi ongelmiksi jo 1960-luvun lopulla, kesti ympäristöhallinnon organisoituminen vuosikymmeniä ja ympäristöministeriö perustettiin vasta vuonna 1983. Tutkimuksessani selvitän, millaisena ympäristökysymyksen kehittyminen näyttäytyy Helsingin Sanomien pilapiirroksissa vuosina 1956-1985. Pilapiirros kertoo enemmän kuin pelkkä uutinen; siitä voi tulkita julkaisuajankohdan asenneilmapiiriä sekä ainakin piirtäjänsä mielipiteen, eli paljon sellaista, jota neutraaliin uutistekstiin ei paineta. Lisäksi se, että pilapiirros on tehty ja julkaistu, paljastaa piirroksessa kuvatun aiheen olevan ajankohtainen ja puhuttava. Tutkimuksen aineistona on Helsingin Sanomien pilapiirrokset vuosilta 1956-1985, jotka ovat kaikki Kari Suomalaisen käsialaa. Ajanjaksolle osuu monia suomalaisen ympäristökysymyksen suuria tapahtumia: yksittäisiä taisteluja, kuten Koijärvi, runsaasti uusien luonnon- ja ympäristönsuojeluun liittyvien lakien säätämisiä sekä ympäristöhallinnon organisaation uudistaminen ja oman ministeriön perustaminen. Tutkimus on yhteiskunnallista ympäristötutkimusta ympäristöhistorian kentällä, ympäristötietoisuuden ja ympäristöliikkeiden historiaan painottuen. Tutkimusote on teorialähtöinen, ja sisällönanalyysi on limittynyt aineistonkeruuvaiheeseen. Lopputuloksena on katselmus siitä, miten ympäristökysymys on kehittynyt Suomessa yksittäisten ympäristöongelmien käsittelystä yhteiskunnalliseksi kysymykseksi
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(2018)In this study 39 methicillin-resistant Staphylococcus aureus CC398 isolates from Finnish pigs and pork were sequenced by whole-genome sequencing. Also, phenotypic antimicrobial resistance of the strains was examined. The strains originated from the culture collection of Finnish Food Safety Authority (Evira) and they were isolated between the years of 2008 and 2017. MRSA strains were isolated from both asymptomatic and infected pigs and pork. The strains represented the four most common spa types in Finnish pigs (t034, t2741, t011 and t108). DNA extraction method for S. aureus was optimized by comparing automatic DNA extraction robot and manual DNA extraction method. Extracted DNA samples were sent to Germany to be sequenced with Illumina sequencing. Paired-end raw read sequences were assembled using three different algorithms: Spades, Idba and Velvet. The assembled sequences were analysed by bioinformatics tools. Possible antimicrobial resistance genes, virulence genes, plasmids and SCCmec cassettes were identified. The strains were also typed by spa typing and sequence typing. spa typing was already performed in Evira using PCR and the new spa typing results were compared to the PCR results. Using the assembled sequences, a phylogenetic tree was also constructed. Phenotypic antimicrobial susceptibility testing was performed using broth microdilution panel. The manual extraction method was slightly better since the extracted DNA was purer. The best assembly algorithm was Spades and because of that all sequences were assembled with that algorithm for further analyses. The strains carried only a few virulence genes and many genes that are important for human infection were missing. All the strains carried the same SCCmec cassette type and sequence type ST398 both of which are known to be typical for pig related MRSA. Illumina sequencing and spa typing were not working perfectly since the used program was not able to distinguish spa types t034 and t011 from each other. The problem was probably due to very similar short tandem repeats that these two spa types share. Also, Illumina sequencing is known to produce short reads that could be problematic for sequence assembly. All the strains were resistant to beta-lactams and tetracycline which is typical for MRSA CC398 strains. Many strains were also resistant to clindamycin and trimethoprim. Antimicrobial resistance seemed to be carried by plasmids in some cases because the strains carried several plasmids that are known to contain antimicrobial resistance genes. The antimicrobial resistance profiles were different between different spa types since some spa types were more resistant to certain antimicrobials than others. According to the phylogenetic tree, the strains seemed to be a very heterogenic group. The strains that belonged in the same spa type were most related to each other as expected. There were no differences between strains originating from pigs and strains originating from pork which strongly indicates that bacteria could have spread from pigs to pork. Asymptomatic pigs also carried similar strains as infected pigs. The strains that were causing infections in pigs did not contain any more virulence factors compared to the other strains. The study gave plenty of new information concerning MRSA CC398 in Finnish pigs and pork. The antimicrobial resistance and virulence patterns in addition to other qualities of the strains were very similar that was described in the literature before. The strains seemed not to be very virulent for humans, but the situation must be observed in case of increasing resistance and virulence. The best way to prevent spreading of MRSA is to decrease the amount of MRSA in pig farms since MRSA bacteria are most likely to spread from pigs to the environment and to the people who work in pig farms and from there to the rest of the population.
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(2020)In the years 2017-2019 there was quite vivid discussion about the level of logging in Finland. Finland, as forested country, had put high hopes of bioeconomy as a strategyline for future. In addition the demand of cellulose and other woodproducts had been on rising track and there was plans to build numereous pulp- and bioproduct plants in Finland. Hence the pressure to increase the level of logging had been risen. In the meantime European union tried to achieve more ambitious climatepolicy and conceived a new LULUCF (land use, land-use change and forestry)-act, which allows to take into acount carbon sinks of forests in each of the member country. Aspiration to increase logging and mitigate climate change and preserve forestnature did not go together very well. As a method in this study theory-based content analysis is used, in which thoughts of economic historian Karl Polanyi of self-regulated markets, fictitious commodities and double movement is applied. According to Polanyi self-regulated markets wake protective counter movements in society. These counter reactions are spontanious and they can emerge from various parts of society. They softened the hit caused to people and nature by markets. Polanyi called this mechanism doudle movement. The material contains mediasources such as articles from Helsingin Sanomat and Yleisradio and also public documents of the state. According to this study the markets determinate the use of forests and the level of logging in Finland. Public policy doesn’t want to compromise the strong export industry and employer such as forestry. The use of forest is organized by the rules of markets and tree is now used as a commodity as a timber, even if nature is not originally produced to sale. Finnish forestry is a small part of growth demanding global capitalist system. As counter movements in this case appear environmental organizations, scientists, journalists, politics and citizens. Those groups were worried about carbon sinks and biodiversity of forests. Also European unoion acted as counter movement, when it demanded reduction of emissions of other sectors like housing and transport if carbon sinks of forests decrease. All in all the power of counter movements wasn’t high enough to change the direction of forestry in Finland, which is over the years embedded in finnish society. A potential conflict can still emerge, when traditional nature based industry navigates in the field of international commerce, which resemble Polanyi’s selfregulated markets. There was clear evidence of counter movements and they got more value from the discussion of climate change and the overall greening of society. On the other hand also lumber industry could present them as green, because they use renewable resources, which also replace fossil fuels. The larger impact on the level of logging is system-based pendulumus counter movement, like depression, which swing the world economy.
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(2018)Lepakot ovat suuri, monimuotoinen ja ekologisesti merkittävä nisäkäslahko. Viime vuosikymmenien aikana ne ovat paljastuneet myös merkittävien zoonottisten taudinaiheuttajien kantajiksi. Suomessa esiintyy kolmetoista lepakkolajia, joista suurin osa esiintyy täällä levinneisyysalueensa pohjoislaidalla ja joiden kantamista taudinaiheuttajista on tehty vielä hyvin vähän tutkimuksia. Tutkielmassani selvitän korona- ja paramyksovirusten esiintymistä eteläisen Suomen lepakoilla vuosina 2013-2016. Lisäksi pyrin kerätyn aineiston perusteella selvittämään, onko näytteitä luovuttaneiden lepakoiden iällä, näytteiden keruukuukaudella tai näytteiden keruualueella vaikutusta löydettyjen virusten esiintyvyyteen. Aineistona käytettiin muiden tutkimusprojektien yhteydessä lepakoilta kerättyjä uloste- ja anaalipyyhkäisynäytteitä sekä lepakoiden päivehtimispaikoilta kerättyjä ulostenäytteitä. Näytteistä eristettiin RNA ja ne seulottiin koronaviruksia ja paramyksoviruksia tunnistavilla ja optimoiduilla kvantitatiivisilla käänteistranskriptio- PCR-menetelmillä (RT-qPCR) ja löydökset varmistettiin tavallisilla käänteistranskriptio-PCR-menetelmillä (RT-PCR). Jälkimmäisistä reaktioista saadut tuotteet myös sekvensoitiin. Ulostenäytteiden seulonnan tuloksista kertyneestä aineistosta tehtiin tilastolliset analyysit yleistetyillä lineaarisilla sekamalleilla, joissa vastemuuttujana käytettiin viruksen esiintymistä ja mallin muuttujina näytteen luovuttaneen lepakon ikäryhmää ja lajia, näytteen keräyskuukautta ja eliömaakuntaa, josta näyte oli kerätty. Mallien satunnaistekijöinä käytettiin näytteiden keräyskuntaa tai näytteiden keräysvuotta. Sekvenssiaineistosta tehtiin fylogeneettiset analyysit käyttäen suurimman todennäköisyyden (Maximum Likelihood) menetelmää ja Bayesilaista menetelmää, joiden tuloksina saatiin kaksi fylogeneettista puuta. Neljän vuoden aineistosta todettiin yhteensä 18 lepakkoyksilöä, jotka kantoivat koronaviruksia, mutta paramyksoviruksia ei aineistosta löydetty. Tilastolliseen tarkasteluun hyväksyttiin 77 ulostenäytettä, joista 13 oli positiivisia koronaviruksille. Anaalipyyhkäisynäytteistä kerättiin 38 kappaletta ja näistä 5 oli positiivisia koronaviruksille. Päivehtimispaikoilta kerättyjä ulostenäytteitä tutkittiin 28 kappaleitta ja näistä 4 oli koronaviruspositiivisia. Koronaviruksia löydettiin Varsinais-Suomen, Uudenmaan, Etelä-Pohjanmaan ja Pohjois-Savon eliömaantieteellisiltä alueilta. Uloste- ja anaalipyyhkäisynäytteiden perusteella koronaviruksia esiintyy Suomessa pohjanlepakoilla, isoviiksisiipoilla, vesisiipoilla ja viiksisiipoilla. Tutkielmassa esitellään ensimmäinen pohjanlepakon beetakoronaviruslöytö. Tämä virus ryhmittyy fylogeneettisissa puissa samaan haaraan muiden saman lepakkosuvun kantamien beetakoronavirusten kanssa ja on samalla melko läheistä sukua MERS-koronavirukselle. Tutkielmassa esitellään myös ensimmäinen isoviiksisiipan koronaviruslöytö, joka fylogeneettisten analyysien perusteella ryhmittyy samaan fylogeneettisen puun haaraan luxemburgilaisen ruskosiipan alfakoronaviruksen kanssa. Eniten koronaviruksia löydettiin vesisiipoilta, jotka suurimmalta osin ryhmittyivät samaan fylogeneettisen puun haaraan. Merenkurkussa sijaitsevasta Mustasaaren kunnasta kerätystä vesisiipan ulostenäytteestä löydetty sekvenssi kuitenkin sijoittui erilleen muista suomalaisista sekvensseistä ja eteläisestä Euroopasta todettujen sekvenssien joukkoon, mikä voi viitata tämän alueen lepakkopopulaation ja sen kantamien virusten levinneen Suomeen läntistä reittiä. Tutkielman tulokset luovat hyvän pohjan jatkotutkimuksille, joissa voidaan selvittää virusten tarkempaa esiintyvyyttä sekä niiden tarkempia ominaisuuksia.
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