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The spreading of non-indigenous species by human activities is a growing problem globally. Invasive species are generally assumed to have negative impacts on ecosystems, because they threaten biodiversity and the balance of ecological systems. Other simultaneous changes in the ecosystem can impact, or intensify the effects of, the invasion. The invasive rock shrimp Palaemon elegans, is an invasive species that has spread to the Baltic sea via human introduction in the early 2000's. There have also been drastic changes in the ecology of Baltic sea, particularly the increase of primary production. A common mesopredator, the three-spined stickleback Gasterosteus aculeatus, has greatly increased in number in the Baltic sea in recent years. It is presumed to influence the primary production by predation of zooplankton grazers. P. elegans is an omnivore that both grazes filamentous green algae, as well as preys upon the invertebrate grazers that live amongst the algae. If the invasion of P. elegans influences the populations of stickleback, it might also influence the accumulation of primary production. Recent studies have shown, that P. elegans can potentially influence the reproductive behavior of stickleback, but the effect on the success of reproduction has not been proven. This study was composed of two parts: field monitoring and a mesocosm experiment. In the monitoring, individuals of stickleback and P. elegans were caught, counted and measured in three shallow bays and two depths from May to August of 2015. The differences in number of caught individuals were analyzed using Kruskal-Wallis analysis of variance and differences in lengths were analyzed with Mann-Whitney U-test. The effect of P. elegans on sticklebacks was analyzed using covariance analysis. The hypothesis was, that the amount of P. elegans and stickleback or their lengths would show negative correlation, which could be a sign of interaction through predation or resource competition. In the mesocosm experiment stickleback fry were exposed to P. elegans or a non-parent stickleback in tanks with filamentous algae Cladophora glomerata and associated fauna. The resulting differences in in fry number, fry size and the amount of algae between treatments in the tanks were analyzed with Kruskal-Wallis analysis of variance. Correlations between variables were analyzed using Spearman's rank-order correlation. The hypothesis was that P. elegans would have a negative effect on the amount of fry through predation, or the size of the fry through perceived predation risk. In the field study, no significant correlations were found between P. elegans and sticklebacks, and therefore the results do not suggest a causal link between the two species. Differences between the areas were found, which were attributed to physical differences between the areas. In the mesocosm experiment not enough repetitions were accumulated to provide reliable results. The increase of P. elegans in the Baltic sea is most likely not going to affect the three-spined stickleback via direct predation. P. elegans appears in the shallow bays where sticklebacks reproduce later in the year and it consumes mainly algae and invertebrates. Even though P. elegans will feed on fish eggs if there is an opportunity, stickleback males defend their nests fiercely. The invasion of P. elegans in the Baltic sea is very recent, but it can affect the accumulation of filamentous algae due to their great number. It feeds on invertebrates, but can itself be a potential food item in the diet of ie. cod.

With growing fragmentation of elephant habitats across the world, elephants are coming in closer contact with humans, leading to increasing human-elephant conflict over limited space and resources. Laikipia county in Kenya represents one such region where conflict with elephants has been (and continues to be) a widespread problem, stemming from intense land-use zoning since the 1970s. This conflict mainly takes the form of crop raiding by elephants in community farmlands adjoining conservation areas. Electric fencing has been the widely used conflict management tool in the region to prevent elephants from entering croplands. However, the establishment of electric fences can often have hidden political underpinnings, both caused by and resulting in conflicting interests of different land users. As human-elephant conflict is multidimensional, it is essential to incorporate both human and wildlife dimensions when assessing the effectiveness of electric fences in conflict mitigation. While there is a growing body of research on the ecological effects of electric fences, the role of social perceptions in long-term fence effectiveness is often neglected. In this study, I therefore conducted a combined social and ecological assessment of electric fences in Laikipia. For this, I evaluated the perceptions of three local communities (Mutara, Ex Erok and Lorien) towards two major electric fences in Laikipia: the West Laikipia Fence and the Lorien Community Fence. I conducted 188 individual interviews with farmers (and opportunistically pastoralists) in all three communities, comprising questions on demographics, human-elephant conflict, electric fences, and involvement of communities in fence management. I then combined this information with data on fence breaking and crop raiding behaviour of elephants to effectively inform electric fence management strategies in the region. First, I looked at changes in the perceptions of Mutara and Ex Erok between 2016-2022, following upgrades made to the West Laikipia Fence after 2016, through a comparison of results with previous research. Second, I investigated potential factors influencing community perceptions towards fence effectiveness. Third, I mapped fence break and crop raiding hotspots in the three communities. And fourth, I determined the environmental factors affecting crop raiding intensity. Both Mutara and Ex Erok showed more positive perceptions towards fence effectiveness in 2022 as compared to 2016. The main factor found to influence fence perceptions was community involvement in fence management. Communities involved in fence management had more positive fence perceptions than those with no involvement. Crop raiding hotspot mapping revealed that some areas within each community were more affected by crop raiding than others. Fence break hotspot mapping identified fence sections of the West Laikipia Fence more prone to breakages by elephants. Finally, crop raiding intensity in a given farm was found to be strongly affected by the diversity of crops grown there, and weakly by its distance from the nearest roads and electric fences. My results therefore contribute to a better understanding of patterns of crop raiding and fence breakages of elephants in Laikipia. My findings highlight the importance of including sociological data from local communities in assessments of electric fence effectiveness, and also provide empirical evidence on the importance of involving local communities in electric fence management. The findings from this study can serve as a reference to relevant stakeholders for future improvements in electric fence management in Laikipia and elsewhere.

The concept of sustainability has been discussed a lot in academic and political contexts. While especially the ecological dimension of sustainability has been widely focused on due to various environmental crises, the social dimension has been less studied. In this thesis, I analyse social sustainability through political discourses in the Finnish context. Finland has received good results in the field of social policy and throughout its history, central labour market organisations have had an institutional role in the development of social policies. This thesis analyses how Finnish central labour market organisations discuss social sustainability when they set their objectives for the 2019-2023 government term. Adopting a critical approach, I study the role and representation of social sustainability in the objective documents. My two-part research 1) constructs a definition for social sustainability based on literature, and 2) analyses the empirical data and discourses found within. The findings of this thesis present a five-part definition for social sustainability and four key discursive themes which emerge from the empirical data. The results from empirical data show that in the objective documents social sustainability is for example discussed in a bureaucratic way, sometimes seen as an instrument benefitting the society. The research also underlines the difficulty of defining and analysing the vague concept of social sustainability and discusses how and why social sustainability could be researched in the future.

Chitinolytic enzymes belong to a group of pathogenesis-related proteins, which are induced in plants by a pathogenic attack. They have also been shown to function in abiotic stresses and related to signalling. Chitinases catalyze the degradation of β-1,4-N-acetyl glucosamine units of chitin. Chitin is not found in plants, but for example the shells of invertebrates, cell walls of certain fungi, algae and bacteria contain it abundantly. Lately chitinases have gathered attention because of their potential utilization possibilities in medicine, agriculture, food industry and biofuels. Strong chitinase gene expression and also chitinolytic activity has been found in a spruce (Picea abies L. Karst.) cell culture, which produces apoplastic lignin into the medium. Plant chitinases are known to be induced also in developmental processes. Chitinase-like genes have been shown to be essential in cellulose synthesis and in development of cell walls and tracheary elements and also affected the localisation of lignin in tissues. Therefore, the secretion of chitinases into the culture medium has not necessarily been caused by stress and chitinases might use also some endogenic substrate in addition to chitin. Because chitin is a structural component of plant pathogens but not present in plants and the growing circumstances of the studied aceptic spruce cell culture were stable, the research hypothesis was, that the secreted chitinases in the culture medium were not a stress reaction but related to development and besides chitin of the pathogens they utilize some own polysaccharide substrate of spruce. Additional hypothesis was connection of the strong expression of chitinases and chitinase-like genes in the culture medium and the production of apoplastic lignin by the spruce cell line. The aim of the study was to characterize the chitinases and chitinase-like enzymes of the spruce cell suspension culture medium and developing xylem by isolating, purifying and cloning them and by producing them heterologously. The aim was also to identify the putative endogenous substrates for the chitinases and chitinase-like proteins to reach better understanding about the meaning of the chitinases in the development of the spruce tissues. Two chitinases of the spruce cell suspension culture were isolated and purified by chromatographic methods. One chitinase gene in spruce cell culture and one chitinase-like gene in spruce xylem were cloned, after which the chitinases and chitinase-like proteins were produced in Pichia pastoris yeast. The total proteins of the culture medium, the purified chitinases isolated from the medium and the chitinases and chitinase-like proteins produced in P. pastoris were used to examine their substrate alternatives with the carbohydrate microarray method. The connection between apoplastic lignin and the chitinolytic enzymes in culture medium was not found and obvious candidates for the endogenous substrates were not detected. However, the mannan degradation in the presence of the chitinases was strong enough to give reason to further analyses.

The thesis explores possibilities for mental health promotion in urban planning trough a case study of the community space in Lapinlahti, Helsinki. Lapinlahti is a former psychiatric hospital, and the area has in the 2010’s been developed through community efforts into a center for mental wellbeing and culture in Helsinki, a “Lapinlahti for all”. The future use of the area has been contested for the past years, with the City of Helsinki and the organizations at Lapinlahti having different views on how the area and it’s cultural and historical mental health legacy should be preserved and developed. In the discussions, statements and visions, the area’s mental health value has also been translated into urban planning, taking many forms. Mental health is a value that has traditionally not been prioritized or regarded as a value of its own in urban planning, and although the relationship between urban form and wellbeing is well known, urban (mental) health is seldom tied to cities physical- and land-use planning (Kim et al, 2022; Corburn 2004). The thesis approaches this topic by analyzing mental health as a planning objective, discussing how different understandings and approaches to mental health have affected the planning visions surrounding Lapinlahti. The thesis uses a theoretical framework of urban governance and critical discourse analysis (CDA) to seek an understanding to the different approaches to the area’s development, and identify the different understandings, connections and visions that surround Lapinlahti. The study identifies three discursive constructions of Lapinlahti: Lapinlahti as a site for cultural heritage, Lapinlahti as a place for mental health, and Lapinlahti as a site for development. The results show that all actors in their development schemes have considered the area’s mental health value from a cultural-historical perspective, viewing the area as a site for mental health history. This history is however understood and manifested in different ways for the actors, influencing different visions for how the area should be developed and what interests and/or values that should guide the development. The thesis continues with presenting three approaches for mental health promotion in urban planning, concluding that planning should be attentive of how the space is governed, the relationship between mental health and the space, and the activities and meanings embedded in space.

Prostate cancer is one of the most common cancers diagnosed in men. Somatic copy number alterations (SCNA), such as the deletion of PTEN or NKX3.1 and the amplification of MYC, have been associated with prostate cancer progression and could serve as potential biomarkers during diagnosis. One approach to utilize this information would involve screening a large number of prostate tissue sections for SCNAs and subsequently validating the findings using a secondary method. This process could enable more personalized treatment options for cancer patients. This thesis aimed to create a robust and reproducible workflow for SCNA identification. This was achieved by optimizing a chromogenic immunohistochemistry (IHC) protocol using immunostaining chambers and open-source 3D-printed laboratory hardware. The optimized protocol was then transferred to an automated liquid handling robot, and a panel of three antibodies for PTEN, NKX3.1, and MYC was developed for SCNA screening with IHC. Additionally, a chromogenic in situ hybridization (CISH) protocol was optimized to validate the results of the IHC. The immunostaining chambers required a lower antibody dilution to perform comparably to the manual IHC stainings. The automated protocol using the liquid handling robot produced high-quality stains with optimized dilutions. The optimized CISH protocol successfully identified the presence of the target gene, but unclear signals and merging of the signals obstructed detailed analysis. While complete deletion of PTEN was detectable, determining the number of gene copies per cell proved challenging due to signal variability and sample-dependent problems. Further optimization of the CISH protocol or development of an automated analysis workflow tailored to address these challenges is needed for more accurate analysis.

Grasslands occur on every continent except Antarctica and are a key part of agricultural and urban landscapes in many parts of the world. In Finland, many of the grassland species are threatened nowadays. Fragmentation, worsening quality and shrinking area of habitats are the biggest threats to grassland species. Many grassland plants, however, can be found in urban habitats such as road verges, different meadows and rocky outcrops. Suitable urban habitats could be important for these species if the degradation of their habitats continues elsewhere. Indicator species could provide information about the ecological quality of urban habitats and thus the suitability for grassland specialists. My aim for this thesis was to determine how indicator species can be used to assess the ecological quality of urban grasslands by answering the following research questions: 1. Does habitat type affect the abundance and occurrence of known quality indicator species of semi-natural grasslands? 2. Which species are characteristic to different urban grassland habitat types? 3. How different sites relate to each other in terms of vegetation? 4. How do the measures used to answer the other three questions compare together? I collected vegetation data from 28 study sites in the cities of Espoo, Helsinki and Vantaa, southern Finland. In addition, a dataset consisting of 116 sites from these cities, collected by another person, was included here. The study sites were divided into eight habitat types: dry and mesic landscape grasslands, dry and mesic road verges, dry and mesic valuable grasslands, rocky outcrops and valuable rocky outcrops. From all study sites, I collected a list of plant species observed within a standardized time frame by doing an on-site vegetation inventory. In addition, I observed the frequencies of plant species within 1 x 1 m vegetation quadrats. I used one-way ANOVA and Tukey-Kramer test as well as Welch’s ANOVA and Games-Howell test to study the effect of habitat type on abundance and occurrence of semi-natural grassland indicator species. I used IndVal to identify which species are indicators for the habitat types and their combinations. I used NMDS to study the grouping of different habitat types and their species. Habitat type affects the abundances and occurrences of semi-natural grassland indicator species in urban settings and these species can be used in evaluation of the ecological quality of urban grasslands. Indicator species produced from observed data seem to have a limited potential in evaluating the ecological quality of urban grasslands, but they provide a good method for classifying urban grassland habitats, especially valuable rocky outcrops and valuable grasslands. Study sites do form groups according to their vegetation, but these groups do not entirely follow the habitat type division used in the study. With right standardization for the use, indicator species can be a valuable tool in assessing the ecological quality of urban grasslands.

The antibiotic resistance of pathogenic bacteria is becoming a major problem in treating bacterial infections and development of new antibiotics is very challenging. In traditional phage therapy the bacteriophages, viruses that infect bacteria, are being used as an optional treatment to eliminate infectious agents. Methicillin resistant Staphylococcus aureus (MRSA) is resistant to several currently used antibiotics and is one of the most common antibiotic resistant bacteria causing infections. Therefore, it is a potential target for the phage therapy. Some of the Staphylococcus aureus strains produce several different enzymes and toxins which can be harmful to patients. Products developed for phage therapy purposes need be free from the material originated from host bacteria. In this study, three different methods were tested for the purification of bacteriophages infecting S. aureus. The main goal was to produce phage lysates with purity and phage concentration suitable for therapeutic purposes using a fast and aseptic procedure upgradable for large volumes. The tested methods were ultrafiltration with filter tubes from two different manufacturers (Sartorius Vivaspin 6 ja Merck Millipore Amicon Ultra 4), polyethylene glycol (PEG) precipitation and ion exchange chromatography. Three different bacteriophage strains were used. One was isolated from a commercial Russian phage therapy product (vB_SauM_fRuSau02) and the other two from feces of pigs (vB_SauS_fPf-Sau02 and vB_SauS_fPfSau03). Host bacteria strains for the first bacteriophage were S. aureus strains TB4 and 13KP originally isolated from human infections. Two host strains for the latter two phages were MRSA strains isolated from healthy pigs. Purification of the phage lysates was evaluated by measurement of enterotoxins produced by S. aureus bacteria, measurement of free double stranded DNA (dsDNA), and by cytotoxicity test in cell cultures. All evaluation methods were commercially available tests. To determine how much of the bacteriophages were lost in the process, the phage concentrations of the lysates were determined before and after the purification and recovery rates were calculated for the viruses. After two separate ultrafiltrations, the recovery rates of the bacteriophages were mainly good, but there was a lot of variation in the results. The lowest recovery rate calculated was 5%, the highest 57%, and the mean of all the rates 24%. In this study the ion exchange chromatography was combined with ultrafiltration which was used in pre-cleaning of the lysates and changing the phages in a buffer suitable for the chromatography. The recovery rates from the ion exchange chromatography varied between 14-26% but the results may be affected by the ultrafiltration steps performed before and after, since a lot of variation was seen in ultrafiltration processes. PEG precipitation was performed for one phage lysate only in order to compare the laboriousness of the method and the rates of the recovery to the other methods used. The rate of recovery from the PEG precipitation was 9,5% which was fairly low. The purity of this lysate was not evaluated since the method was estimated to be too laborious compared to the other methods. Ultrafiltration turned out to be an efficient method in the removal of small protein molecules, such as enterotoxins from bacteriophage lysates. With two sequential ultrafiltrations 96-99% of the enterotoxins in the lysates were removed. The removal of the free dsDNA was also successful but there was variation between the phage lysates. Approximately 67-93% of the free dsDNA was removed but it is possible that some of the measured DNA originated from lysed bacteriophages as their genome also consists of dsDNA. Ion exchange chromatography produced extremely well purified phage products. The fractions had no enterotoxins left or the amount was below the detection limit of the test (<0,5-1 ng/g). Ion exchange chromatography was able to remove 96-99% of the free dsDNA of the lysates. It is possible that some of the DNA left in the lysates originated from the bacteriophages lysed during the process or in storage after that. When comparing how simple and fast the methods were, the ultrafiltration turned out to be superior. It can be used in fast production of bacteriophage products for the treatment of S. aureus infections. The purification achieved with the ultrafiltration should be adequate for a topical use of the product. When higher purity products are required, e.g. for administrating the product intravenously, ion exchange chromatography might be a safer option.

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.

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.