Skip to main content
Login | Suomeksi | På svenska | In English

Browsing by Title

Sort by: Order: Results:

  • Ojaranta, Arja (2022)
    The subarctic ponds of northern Fennoscandia are often clear-water, fish-free and oligotrophic (relatively low primary production). The ponds in the area are useful physical geography research sites, as the human impact in these areas is relatively small. These ponds are often phosphorus-limited and serve as good indicators of air pollution. Understanding and anticipating changes in water chemistry is particularly important for both the people and the ecosystems in the region. Changes in these ecosystems due to the climate change, for example, can be harmful. The effects of the climate change are and will continue to be strongest in arctic and subarctic areas. The current relatively short growing season is lengthening, so habitats and vegetation zones will either relocate or, alternatively, organisms and plants will have to adapt to the changing conditions. Yet many of the cold-water endemic species worldwide will become extinct. The aim of this thesis was to focus on the biomass of benthic algae growing on the rocks of subarctic ponds. These cyanobacteria, green algae, and diatoms are important primary producers in subarctic ponds and an important part of the food web in these waters. The biomass in this thesis refers to the actual amount of benthic biomass expressed by the amount of dissolved nutrients (not their theoretical, potential amount). The aim of the thesis was to find out how well the physical variables (pond area, average water temperature of the last month of measurement and median solar radiation) and chemical variables (water metal and nutrient concentrations, pH, and conductivity) explain the benthic biomass of subarctic ponds. The Kilpisjärvi area is the only area in Finland that belongs to the old Caledonian orogeny range in the northern part of Fennoscandia. All these 39 ponds were studied, and they are located in Kilpisjärvi in Finnish Lapland, in the areas of about 30 km² of Malla Strict Nature Reserve and about 40 km² of Ailakkavaara, at altitudes of 486–882 m a.s.l. Some of the ponds are located above and some below the tree line. Water samples were collected in August 2020, when data from continuous temperature and radiation meters installed in the late summer of 2019 were also read. During the sampling of the ponds, the biomasses of epilithic, rock-bearing benthic algae groups were measured with a BethoTorch field device and a water pH with a YSI PRO field meter. Water samples were analyzed for metal concentrations by ICP-MS and nutrient concentrations by IC. The results obtained after this spectrometric and chromatographic laboratory analyzes were analyzed statistically, including by means of a generalized linear model (GLM). The water chemistry of the ponds and the biomass of benthic algae are affected by many biotic and abiotic factors. Among other things, geographical location, topography, and climate (in the polar region or the equator) affect both water chemistry and pond biomass. The total metal concentrations in the studied ponds ranged from about 20 to 220 μg/l and the nutrient concentrations from about 2 to 17 mg/l. Based on the results, the chemical variables explained the occurrence of 57 % diatoms, 56 % green algae, and 27 % cyanobacteria, and the physical variables explained 28 % diatoms, 8 % green algae, and 4 % cyanobacteria. According to the F-test, of the chemical variables, the metal concentrations in the water played the largest role in the biomass of benthic algae. The pond area had the largest impact from the physical variables. Surprisingly, nutrients did not appear to play much role in the benthic biomass, although the literature suggests that. The warmer the water, the more likely cyanobacteria are the dominant species and the colder the water more likely are diatoms. This is because the growth peak of cyanobacteria coincides with the warmest time of the year, late summer, and diatoms in springtime immediately after the break-up of ice. The advantage of the BenthoTorch instrument was it is ease of use and speed of measurement, but more specific results could have been obtained, for example, by microscopy of the abundance of the benthic species. In the future, special attention should be paid to the stabilization of chlorophyll-a concentrations in the measurement of benthic algae biomasses. This could produce results that are more consistent and comparable.
  • Öhman, Jenny (2018)
    Många elever i grundskolan anser att fysiken är ganska ointressant. Problemet ofta är att de inte förstår att fysiken faktiskt har med deras egen vardag att göra. Det kan vara svårt för en elev att uppfatta och förstå vad som händer på en atomnivå. Genom att använda sig av vardagliga exempel och ta ner fysiken till en vardaglig nivå väcker man intresse hos eleverna. I bästa fall förstå eleverna fysikaliska fenomen bättre då man tar exempel ur vardagen. Eleverna kan bättre förstå ämnet. Den nya läroplanen har försökt att poängtera att det är viktigt att ta upp vardagliga fenomen i fysikundervisningen, så vi är påväg mot rätt håll. Denna avhandling förklarar fysiken bakom vardagliga fenomen. Fenomenen är tagna från många olika vardagliga sammanhang, som till exempel nyheter och idrott. Elever har olika intressen och därför är det viktigt att ta fenomen från olika sammanhang, så att alla elever kan känna att detta berör just mig och min vardag. Detta material visar också hur man kan utgå från ett fenomen och sedan gå till fysiken, istället för att först fundera på formler och sedan tillämpningar. Många elever har tappat intresset då man talar om formler och är inte lika uppmärksamma sedan när man talar om olika fenomen (om man gör det).
  • Pylkäs, Marjut (2013)
    Gabrielin torvi on kolmiulotteinen matemaattinen kappale, jonka pinta-ala on ääretön, mutta jonka tilavuus on korkeintaan piin suuruinen. Kappaleen olemassaolon huomasi italialainen fyysikko Evangelista Torricelli. Gabrielin torven olemassaolo hämmensi 1600-luvun matemaatikkoja, koska matemaattiset metodit ja tieto eivät olleet vielä kehittyneet niin paljon, että Gabrielin torven kaltaisille kappaleille olisi pystytty antamaan ymmärrettäviä todisteita. Kappaleen nimi viittaa kristillisen mytologian tuomiopäivään, jolloin arkkienkeli Gabriel puhaltaa torveensa ja tunnettu, äärellinen maailmamme loppuu yhdistyen päättymättömään jumalaiseen todellisuuteen. Nimi kuvaa kappaletta hyvin, sillä Gabrielin torvessa yhdistyy äärellinen ja ääretön mielenkiintoisella tavalla. Kochin lumihiutale on Gabrielin torven analogia tasossa. Se on tasokuvio, jonka pinta-ala on äärellinen, mutta sen piirin pituus on ääretön. Tämän kaiken ja muut lumihiutaleen mielenkiintoiset ominaisuudet löysi ruotsalainen matemaatikko Helge von Koch vuonna 1904. Kochin löydökset olivat merkittävä etappi fraktaalitutkimuksen saralla. Gabrielin torvea ja Kochin lumihiutaletta voisi ensisilmäyksellä luulla paradokseiksi, mutta sitä ne eivät kuitenkaan ole. Sekä torvea, että lumihiutaletta voi käyttää peruskoulun ja lukion matematiikan opetuksessa elävöittämään opiskelua ja tuomaan lisää syvyyttä käsitteisiin.
  • Koskela, Aurora (2024)
    Galaxy properties and their environment are known to be correlated, but the dominant physical mechanism behind this correlation is still unknown. The effect of environment can clearly be seen in the transformation of galaxy morphology and colour. The Sérsic profile and the Sérsic index n are a common way to study the light profiles and the ratios of different galaxy components. The COSMOS-Web program’s goal is to conduct a survey of the deep field of the Universe with the recently launched James Webb Space Telescope (JWST). Deep field imaging has previously been done with the Hubble Space Telescope, and JWST will give us new information about the early Universe and the galaxy evolution within it. This thesis presents a comparison study of galaxy properties between galaxy group members and field galaxies, using the new JWST data. The distributions over the Sérsic index, disk and bulge radius, star formation rate and stellar mass, as well as their respective p-values are plotted and calculated. The galaxies were divided into four stellar mass bins µ = log(M ) (8 < µ < 9, 9 < µ < 10, 10 < µ < 11, 11 < µ < 12), redshift bins (z < 0.5, 0.5 < z < 1, 1 < z < 2, 2 < z < 3) and in some cases an additional condition of n < 2.5 and n > 2.5 was used. The galaxy properties over Sérsic index, disk and bulge radii and star formation rate are similar within stellar mass bins, but differences can be seen in the distributions over stellar mass. Differences between distributions over disk radius are found in the case of low redshift z < 0.5 and low Sérsic index. In the highest redshift bin of 2 < z < 3, differences between galaxy disk radii are seen with both n < 2.5 and n > 2.5. The distribution over richness of AMICO-COSMOS galaxy groups and clusters is also presented, showing the groups to be low-mass.
  • Lehtomäki, Wille (2018)
    Työn päätavoitteena on osoittaa viidennen asteen polynomiyhtälön ratkaisukaavan mahdottomuus. Ratkaisukaava on mahdollista muodostaa vain polynomeille, jotka ovat juurtamalla ratkeavia. Juurtamalla ratkeavan polynomin kukin juuri voidaan ilmaista kerroinkunnan alkioiden muodostamana päättyvänä lausekkeena, joka käyttää vain kunnan laskutoimituksia ja juurenottoa. Työn lähtökohdaksi otetaan kuntien laajennukset ja ennen kaikkea polynomin kerroinkunnan laajennukset polynomin juurilla. Kun kerroinkuntaa laajennetaan juuri kerrallaan, syntyy useiden sisäkkäisten kuntalaajennusten torni, jonka huipulla on polynomin kaikki juuret sisältävä polynomin juurikunta. Galois'n teorian keskeisimpiä työvälineitä ovat automorfismit eli kunnan isomorfismit itselleen. Sellaiset laajennuskunnan automorfismit, jotka kiinnittävät laajennuksen lähtökunnan, muodostavat laajennuksen Galois'n ryhmän. Myös polynomille on mahdollista määritellä Galois'n ryhmä: polynomin Galois'n ryhmä on sen juurikunnan Galois'n ryhmä polynomin kerroinkunnan suhteen. Osoittautuu, että kukin Galois'n ryhmän alkio on samaistettavissa jonkin polynomin juurten permutaation kanssa, joten Galois'n ryhmä on siis aina symmetrisen ryhmän aliryhmä. Työn loppupuolella keskiöön nousevat juurilaajennukset eli kunnan laajennukset kunnan alkioiden juurroksilla. Kun sopivaan juurilaajennukseen sovelletaan kuudennessa luvussa todistettavaa Galois'n teorian peruslausetta, osoittautuu, että juurtamalla ratkeavan polynomin Galois'n ryhmästä löytyy aina tietty sisäinen rakenne, jota kutsutaan ratkeavuudeksi. Viimeisessä luvussa osoitetaan, että polynomin Galois'n ryhmän ratkeavuus on välttämätön ja riittävä ehto polynomin juurtamalla ratkeavuudelle. Viiden ja sitä useamman alkion symmetrinen ryhmä ei kuitenkaan ole ratkeava, mutta on olemassa polynomeja, joiden Galois'n ryhmä se on. Näin ollen polynomeille, joiden aste on viisi tai sitä korkeampi, ei ole mahdollista muodostaa yleistä ratkaisukaavaa. Työn päättää esimerkki viidennen asteen polynomista, joka ei ole juurtamalla ratkeava.
  • Kukkamäki, Mikael Valter (2024)
    The rapid growth and increased requirements within the game development process have made it largely dependent on time, effort and complexity. Game engines were developed to reduce these constraints, by providing game developers with useful features and tools. However, there also lies a deep problem, which is the dependency formed between game developers and the engine administration, the upper management who controls the engine. This dependency relies on the engine administration to maintain their engine without causing harm towards their users. A major conflict happened in the autumn of 2023 between the indie development community and Unity Technologies. Motivated by this conflict we set goals within this thesis to assess the relationship and dependency between game developers and engine administration, and to provide awareness towards trust issues and the impact towards the game industry. In this thesis, we approach this problem with three methods: survey, interviews, and a case study. Development teams participated in the survey, from which three developers were selected for interviews. The game developers described multiple events that formed the basis for the case study, which focused on the past events within Unity Engine. The results show that Unity has considerable value for game developers, but trust in Unity has been significantly impacted by the recent actions of its administration. Developers were met with serious considerations to change their game engine, whether the administration would not regain their lost trust. Despite this, the developers still hope that the engine recovers and the administration takes action to regain their trust. As a conclusion, we emphasize the interaction between game developers and engine administration, what would lead to their mutual interest, in other words creating games.
  • Makkonen, Lauri (2018)
    Tutkielmassa esitellään Eulerin gammafunktio ja siihen liittyviä keskeisiä tuloksia. Gammafunktio on kertomafunktion yleistys reaaliluvuille lukuun ottamatta ei-positiivisia kokonaislukuja. Tutkielma liittyy matemaattisen analyysin alaan, joka käsittelee reaaliarvoisia funktioita. Tutkielmassa käytetään lauseita, jotka on todistettu matematiikan perusopinnoissa, joten ne oletetaan tunnetuiksi. Kertomafunktion yleistäminen oli 1600-luvulla merkittävä interpolaatio-ongelma, jota pohtivat monet suuret matemaatikot. Vuonna 1729 Euler ratkaisi ongelman esittämällä gammafunktion äärettömänä tulona ja seuraavana vuonna esitti sen integraalimuodon. Tämä integraalimuoto esitellään nykyisin yleensä ensimmäisenä, kun puhutaan gammafunktiosta. Tutkielman alussa perustellaan, miksi gammafunktio on sellainen kuin se on. Gammafunktion eri esitysmuotoja esitellään kronologisessa järjestyksessä tukeutuen oivaltaviin näkökulmiin, minkä jälkeen gammafunktio määritellään tarkasti. Gammafunktioon liittyvät keskeiset lauseet todistetaan. Tärkeimpänä lauseena Bohrin-Mollerupin lause, jonka mukaan kaikista kertomafunktion yleistyksistä vain gammafunktio on logaritmisesti konveksi. Viidennessä luvussa todistetaan gammafunktiolle Weierstrassin tuloesitys, johon liittyy oleellisesti myös Eulerin-Mascheronin vakio. Weierstrassin tuloesitystä käytetään tutkielmassa muissa todistuksissa. Tämän jälkeen esitellään joitakin esimerkkejä ja sovelluksia. Gammafunktiota sovelletaan erittäin laajasti monilla aloilla. Se on keskeinen työkalu toki analyysissä, mutta myös tilastotieteessä, todennäköisyyslaskennassa ja lukuteoriassa. Tutkielmassa esitellään vain osa näistä sovelluksista. Gammafunktion avulla saadaan laskettua myös n-ulotteisen pallon tilavuus. Tutkielman lopuksi esitellään kompleksiarvoinen gammafunktio. Luvussa esitellään myös gammafunktion yhteys Riemannin zetafunktioon. Tämä analyyttisen lukuteorian sovellus on gammafunktion yksi tärkeimmistä sovelluksista.
  • Kaipainen, Jussi (2015)
    Pollution is of concern for human health and the environment. Authorities have set concentration frames for many pollutants. Therefore, monitoring is required in industrial and farming activities, for example. Methods based on gas chromatography - tandem mass spectrometry are mainly utilized in the study of trace pollutants in the environmental samples. The main reason for that being versatility and robustness of the technique, which is capable of analysis of numerous compound groups covering all the main pollutants. This thesis focuses on recent gas chromatography - tandem mass spectrometry method development in environmental analysis. Samples of air particulate matter and from aqueous environment are covered. Optimization of tandem mass spectrometry parameters, such as excitation energies, the choice of precursor ions and product ions are shown. Tandem mass spectrometry techniques increase sensitivity and selectivity of the analysis by reducing baseline due to specific fragmentation. For the reason of comparison, conventional one dimensional mass spectrometric applications are shown and advantages and disadvantages of both approaches are discussed. Research papers published during past decade were reviewed. Studied material included research results of gas chromatography- tandem mass spectrometry applications for determination of organic compounds, such as endocrine disruptive compounds, organometals, illicit drugs, pharmaceuticals, pesticides, brominated and chlorinated organic compounds, some volatile organic compounds, organonitrogen compounds and polycyclic aromatic hydrocarbons, in environmental samples. Sample collection and preparation techniques utilized in applications are reviewed as well. In the experimental part of this study, gas chromatography - mass spectrometry method for the determination of carboxylic acids, phenols and sugars in aerosol particles was developed. The experimental part covers also the study of fatty acids, which are analyzed utilizing the same method. Fatty acids are qualitative trace markers for agriculture based pollution in air. Result of the practical application of fatty acids as trace marker is presented as well. Developed method for determining fatty acids was utilized in field campaign in Bologna, Italy. C18/C16 –ratio is trace marker of agricultural based emission. Campaign results of C18/C16 –ratio and is presented in this thesis. Day-of-week trend of fatty acid emission is covered as well. The utilization of tandem mass spectrometry will reduce common matrix effects of gas chromatography - mass spectrometry and in this way will make analysis more sensitive. Tandem mass spectrometry methods will complete to the requirements of environment monitoring and thus are highly recommended in environmental analysis.
  • Wei, Haoyu (2022)
    Ultrasonic guided lamb waves can be used to monitor structural conditions of pipes and other equipment in industry. An example is to detect accumulated precipitation on the surface of pipes in a non-destructive and non-invasive way. The propagation of Lamb waves in a pipe is influenced by the fouling on its surface, which makes the fouling detection possible. In addition, multiple helical propagation paths around pipe structure provides rich information that allows the spatial localization of the fouled area. Gaussian Processes (GP) are widely used tools for estimating unknown functions. In this thesis, we propose machine learning models for fouling detection and spatial localization of potential fouled pipes based on GPs. The research aims to develop a systematic machine learning approach for ultrasonic detection, interpret fouling observations from wave signals, as well as reconstruct fouling distribution maps from the observations. The lamb wave signals are generated in physics experiments. We developed a Gaussian Process Regression model as a detector, to determine whether each propagation path is going across the fouling or not, based on comparison with clean pipe. This binary classification can be regarded as one case of the different fouling observations. Latent variable Gaussian Process models are deployed to model the observations over the unknown fouling map. Then Hamiltonian Monte Carlo sampling is utilized to perform full Bayesian inference for the GP hyper-parameters. Thus, the fouling map can be reconstructed based on the estimated parameters. We investigate different latent variable GP models for different fouling observation cases. In this thesis, we present the first unsupervised machine learning methods for fouling detection and localization on the surface of pipe based on guided lamb waves. In these thesis we evaluate the performance of our methods with a collection of synthetic data. We also study the effect of noise on the localization accuracy.
  • Wei, Haoyu (2022)
    Ultrasonic guided lamb waves can be used to monitor structural conditions of pipes and other equipment in industry. An example is to detect accumulated precipitation on the surface of pipes in a non-destructive and non-invasive way. The propagation of Lamb waves in a pipe is influenced by the fouling on its surface, which makes the fouling detection possible. In addition, multiple helical propagation paths around pipe structure provides rich information that allows the spatial localization of the fouled area. Gaussian Processes (GP) are widely used tools for estimating unknown functions. In this thesis, we propose machine learning models for fouling detection and spatial localization of potential fouled pipes based on GPs. The research aims to develop a systematic machine learning approach for ultrasonic detection, interpret fouling observations from wave signals, as well as reconstruct fouling distribution maps from the observations. The lamb wave signals are generated in physics experiments. We developed a Gaussian Process Regression model as a detector, to determine whether each propagation path is going across the fouling or not, based on comparison with clean pipe. This binary classification can be regarded as one case of the different fouling observations. Latent variable Gaussian Process models are deployed to model the observations over the unknown fouling map. Then Hamiltonian Monte Carlo sampling is utilized to perform full Bayesian inference for the GP hyper-parameters. Thus, the fouling map can be reconstructed based on the estimated parameters. We investigate different latent variable GP models for different fouling observation cases. In this thesis, we present the first unsupervised machine learning methods for fouling detection and localization on the surface of pipe based on guided lamb waves. In these thesis we evaluate the performance of our methods with a collection of synthetic data. We also study the effect of noise on the localization accuracy.
  • Syrjänen, Ossi (2015)
    Gaussin-Bonnet'n lause on differentiaaligeometriassa keskeinen tulos, joka on nimetty Carl Friedrich Gaussin ja Pierre Ossian Bonnet'n mukaan. Lause liittää avaruuden geometrian ja topologian toisiinsa, hyödyntäen geometrisia ja topologisia invariantteja, eli sopivissa muunnoksissa muuttumattomia suureita. Ensimmäisessä luvussa esitellään sileät monistot ja ensimmäisiä perustavanlaatuisia askelia differentiaaligeometrian suuntaan. Aiheen geometrinen luonne ei pelkkien sileiden monistojen tapauksessa nouse vielä ilmiselvästi esiin, vaikka tangenttivektorit ja -avaruudet pystytäänkin jo määrittelemään. Siinä missä topologinen monisto yleistää euklidisen avaruuden ''hyvät'' topologiset ominaisuudet, saadaan sileisiin monistoihin siirryttäessä käyttöön myös keinoja käsitellä suuntia sekä tehdä differentiaalilaskentaa. Perusmääritelmien lisäksi käsitellään muita tärkeitä tuloksia, kuten differentiaalimuotoja ja pintapuolisesti monistoilla integroimisen teoriaa. Toisessa luvussa tartutaan varsinaiseen Riemannin geometriaan ja edetään sileistä monistoista Riemannin monistoihin. Vihdoin selkeämpi geometrisyys tulee esille, kun monistoille määritelty Riemannin metriikka mahdollistaa etäisyyksistä ja kaarevuudesta puhumisen. Konnektioiden avulla mahdollistetaan sileä siirtymä tangenttiavaruudesta toiseen ja päästään käsiksi suunnistetun derivaatan yleistykseen kovarianttiin derivaattaan sekä euklidisen avaruuden suoran viivan yleistyksiin geodeeseihin. Tämän koneiston avulla pystytään määrittelemään monta eri tilanteisiin sopivaa kaarevuuden käsitettä, joiden avulla avaruuden muodosta saadaan tietoa. Viimeisessä, kolmannessa, luvussa määritellään muutamia aiempiin aiheisiin kuulumattomia Gaussin-Bonnet'n lauseen kannalta tarpeellisia käsitteitä. Tilan säästämiseksi algebrallista topologiaa vaativat todistukset sivuutetaan. Lisäksi ''Umlaufsatzin'' eli kiertokulmalauseen todistus sivuutetaan. Lopuksi todistetaan Gaussin-Bonnet'n kaava ja sen avulla itse Gaussin-Bonnet'n lause. Gaussin-Bonnet'n lause on erittäin merkittävä tulos mm. siksi, että se yhdistää niin erilaiset suureet toisiinsa: lokaalista geometriasta kumpuavan Gaussin kaarevuden ja Eulerin karakteristikan, joka on globaali topologinen invariantti. Gaussin-Bonnet'n lause toimii vain 2-ulotteisten monistojen tapauksessa, mutta sille on olemassa monia korkeampiulotteisia yleistyksiä. Näiden yleistysten avulla joitain lauseen geometrisistä ja topologisista seurauksista saadaan hyödynnettyä muissakin monistoissa. Näitä edistyneempiä tuloksia ja muuta, esoteerisempaa, Riemannin geometriaa ei tässä tutkielmassa käsitellä.
  • Ture, Tsegaye (2021)
    The introductory section of the thesis discusses on the European General Data Protection Regulation, abbreviated GDPR, background information and historical facts. The second section covers basic concepts of personal data and GDPR enforcement. The third section gives detailed analysis on data subject rights as well as best practices for GDPR compliance to avoid penalties. The fourth section concentrates on the technical aspects of the right to be forgotten, solely concentrating on the technical aspects of permanent erasure/deletion of personal or corporate data in compliance with the customer’s desire. Permanent deletion or erasure of data, technically addressing the issue of the right to be forgotten and block chain network technology are the main focus areas of the thesis. The fifth section of the thesis profoundly elaborates block chain and the relation with GDPR compliance in particular. Then the thesis resumes explaining about security aspects and encryption, confidentiality, integrity and availability of data as well as authentication, authorization and auditing mechanisms in relation to the GDPR. The last section of the thesis is the conclusion and recommendation section which briefly summarizes the entire discussion and tries to suggest further improvements
  • Stenholm, Noora (2015)
    Involuntary displacements are more common than ever, and the reasons vary from natural disasters, wars and conflicts to environmental degradation and development-induced displacement. Typically, the victims of these phenomena inhabit the Global South, and are further impoverished due to the lack of having a say where and how to live. The lack of social justice and recognition of social development is typical in large-scale involuntary displacements, and also affects to the abilities of people to reconstruct and recover after resettlement. The linkage between forced migration and risk to impoverishment has been widely acknowledged especially in cases that lack participatory measures and proper compensation for the victims. When the impacts are recognized, it is understood that forced resettlement has effects in the economic, social, and physical spheres of life, and can be a major burden for the urban poor. However, involuntary displacement also disrupts the attachments and constructions of sense of place, which have further impacts on social cohesion. The question of community reorganization is crucial in the context where resettlement is simultaneous and combines various heterogeneous groups. The aim of this research is to examine the extent and quality of rehabilitation after involuntary displacement in an urban environment in Sri Lanka. The focus in this research is given to women, as gender is a significant factor in resettlement outcomes, yet it is often ignored in planning and implementation. Gender roles and norms in Sri Lanka are still fixed and conventional, making it an interesting approach to study resettlement and rehabilitation and the daily interactions and perceptions on them. A case study for this research took place in four resettlement sites in the outskirts of Colombo Metro Region, Sri Lanka, which is in the midst of significant urban development plans that aim to relocate tens of thousands of slum dwellers in the need to release prime lands for investments, simultaneously beautifying the city and fighting frequent flooding. The methodological approach applied in this study addresses feminist geography while it looks at rehabilitation measures in the everyday life point of view. It utilized semi-structured interviews of resettled women as a key research method. The case study took place in upgraded underserved settlements that inhabit tsunami-displaced people and development-induced displaced people. Also local experts were interviewed in order to gain a broader understanding of the dynamics and urban policies in the Colombo Metro Region. The case evidences that rehabilitation is a slow process of adaptation, and that physical assets alone cannot improve the livelihoods of slum dwellers. More emphasis should be put into the social relations and community dynamics if participatory measures and development-from-within are to fully deliver. Also full tenure is needed in order to the people to adapt to the mainstream society. For women the question of belonging and reconstructing the sense of place is essential as they spend a lot of their time at home and the immediate environment, and are traditionally in charge of homemaking. Therefore the sense of place and community are essential in the creation of social cohesion and management of the new neighborhood, and along with gender sensitive approaches should not be overlooked if sustainable resettlement is to be pursued as a consequence of ever more crowded cities of the South.
  • Horn, Janina (2020)
    Tutkielman tavoitteena on esittää, että lukion todennäköisyyslaskennan käsitteet ja teoriat voidaan opettaa ja opiskella oppikirjojen perinteisistä esimerkeistä poikkeavassa kontekstissa. Kontekstiksi valitaan todennäköisyyslaskennan mallien todellinen sovellusalue. Samalla luodaan tehtäväpaketin muodossa ainerajat ylittävä opetusprojekti lukioon. Tutkielmassa perustellaan, miksi evoluutio ja populaatiogenetiikka ovat hyvä asiayhteys lukion todennäköisyyslaskennen opetuksessa ja toisin päin. Opetusprojektin toteutus noudattaa soveltaen tutkivan oppimisen menetelmää. Oppiainekohtaisten tavoitteiden saavuttamisen lisäksi yksi opetusprojektin päätavoitteista on oppilaiden ajattelutaitojen kehittäminen, sillä opiskeltavien asioiden syvällinen ymmärtäminen tapahtuu ajattelun kautta. Tutkielmassa on rakennettu tehtäväpaketti, joka koostuu 15 tehtävästä. Tehtävät liittyvät todennäköisyyslaskentaan, evoluutioon ja populaatiogenetiikkaa. Tehtävät alkavat yksinkertaisista käsitteiden määrittelytehtävistä ja peruslaskutehtävistä muuttuen vähitellen tiedon soveltamista vaativiksi ongelmanratkaisutehtäviksi. Opiskelijalla on aktiivinen rooli tiedonhakijana, ja opiskelijoiden keskinäiset keskusteltu ja yhteistyö ovat keskeisessä roolissa prosessissa, jonka tavoite on uuden tiedon rakentaminen.
  • Muniandy, Maheswary (2014)
    The study of obesity has drawn wide-spread interest because of its far-reaching consequences. Obesity is on the rise and has been linked to several clinical complications such as type 2 diabetes and hypertension. Obesity is defined as a condition in which body mass index (BMI) is greater than 3m2/kg. BMI itself is highly heritable with the rate of heritability in twin and adoption studies ranging from 45%–85%. The study was designed to analyze the differences in gene expression in MZ twin pairs discordant for BMI. A total of 26 twin pairs were selected based on a within-pair BMI difference of more than 3 kg/m2 when compared to his or her twin. The twins for this study belonged to either FinnTwin16 (birth cohort 1975-1979) or FinnTwin12 (birth cohort 1983-1987). Samples were extracted from the participants and used in microarray experiments. The resulting data was processed using various packages of the Bioconductor software. The quality control process identified one sample as faulty and as a result the sample as well as the sample of the twin were discarded. This resulted in a sample size of 50 twins. Differential analysis carried out using the limma package of Bioconductor revealed 980 genes that were differentially expressed. These genes were then processed further in the Ingenuity Pathway Analysis (IPA) tool as well as the BiNGO tool. This revealed the molecular networks, gene pathways and gene annotations that were pertinent to the genes uploaded. IPA also provided a list of functions and diseases these genes were involved in. As the final step, the prevalent themes across these results were summarized. This analysis provided many leads that should be investigated further in future studies. It is suggested that future studies start with precise, concrete biological questions that narrow down the scope of biological analysis. This is in view of the extensive amount of data available via microarray studies and the myriad of hypothesizes that can be investigated.
  • Rantanen, Frida (2024)
    Essential thrombocythemia (ET) is a clonal hematopoietic disease characterized by an abnormal increase of platelets in the circulation, with increased risk of thrombosis and hemorrhage. Despite megakaryocytes having a central role in the disease, few studies have investigated their gene expression in ET. The aim of this study is to characterize the gene expression profiles of megakaryocytes from ET patients harboring different driver mutations, and increase the knowledge of the molecular mechanisms underlying the pathophysiology of the disease. In this study, samples were obtained from healthy donors and ET patients with JAK2 V617F, CALR Type I, CALR Type II driver mutations and triple-negative patients. Following megakaryocyte culture from peripheral blood and RNA sequencing, the data was pre-processed and analyzed using differential gene expression analysis. The downstream analysis was conducted using pathway enrichment analysis tools. The analysis revealed that all mutants shared common deregulated genes related to processes involving platelets and coagulation. However, it was shown that CALR and JAK2 V617F mutants also have distinct patterns of gene expression. CALR Type I mutants had a unique gene expression signature consisting of genes related to immune response, as well as metabolic, regulatory, proliferative, and inflammatory pathways, while CALR Type II mutants had unique genes related to ribosomes. The CALR mutants also shared a common anti-inflammatory response signature which set them apart from JAK2 V617F mutants. In conclusion, this study shows that the gene expression profiles of ET mutants are heterogeneous. Moreover, the results provide new insights into the gene expression profiles of CALR mutants that distinguish them from the other mutants. Further experiments using single-cell RNA sequencing methods could build upon these findings and uncover the observed gene expression discrepancies between CALR and JAK2 mutants with increased accuracy.
  • Säkkinen, Niko (2020)
    Predicting patient deterioration in an Intensive Care Unit (ICU) effectively is a critical health care task serving patient health and resource allocation. At times, the task may be highly complex for a physician, yet high-stakes and time-critical decisions need to be made based on it. In this work, we investigate the ability of a set of machine learning models to algorithimically predict future occurrence of in hospital death based on Electronic Health Record (EHR) data of ICU-patients. For one, we will assess the generalizability of the models. We do this by evaluating the models on hospitals the data of which has not been considered when training the models. For another, we consider the case in which we have access to some EHR data for the patients treated at a hospital of interest. In this setting, we assess how EHR data from other hospitals can be used in the optimal way to improve the prediction accuracy. This study is important for the deployment and integration of such predictive models in practice, e.g., for real-time algorithmic deterioration prediction for clinical decision support. In order to address these questions, we use the eICU collaborative research database, which is a database containing EHRs of patients treated at a heterogeneous collection of hospitals in the United States. In this work, we use the patient demographics, vital signs and Glasgow coma score as the predictors. We devise and describe three computational experiments to test the generalization in different ways. The used models are the random forest, gradient boosted trees and long short-term memory network. In our first experiment concerning the generalization, we show that, with the chosen limited set of predictors, the models generalize reasonably across hospitals but that only a small data mismatch is observed. Moreover, with this setting, our second experiment shows that the model performance does not significantly improve when increasing the heterogeneity of the training set. Given these observations, our third experiment shows that
  • Williams Moreno Sánchez, Bernardo (2022)
    The focus of this work is to efficiently sample from a given target distribution using Monte Carlo Makov Chain (MCMC). This work presents No-U-Turn Sampler Lagrangian Monte Carlo with the Monge metric. It is an efficient MCMC sampler, with adaptive metric, fast computations and with no need to hand-tune the hyperparameters of the algorithm, since the parameters are automatically adapted by extending the No-U-Turn Sampler (NUTS) to Lagrangian Monte Carlo (LMC). This work begins by giving an introduction of differential geometry concepts. The Monge metric is then constructed step by step, carefully derived from the theory of differential geometry giving a formulation that is not restricted to LMC, instead, it is applicable to any problem where a Riemannian metric of the target function comes into play. The main idea of the metric is that it naturally encodes the geometric properties given by the manifold constructed from the graph of the function when embedded in higher dimensional Euclidean space. Hamiltonian Monte Carlo (HMC) and LMC are MCMC samplers that work on differential geometry manifolds. We introduce the LMC sampler as an alternative to Hamiltonian Monte Carlo (HMC). HMC assumes that the metric structure of the manifold encoded in the Riemannian metric to stay constant, whereas LMC allows the metric to vary dependent on position, thus, being able to sample from regions of the target distribution which are problematic to HMC. The choice of metric affects the running time of LMC, by including the Monge metric into LMC the algorithm becomes computationally faster. By generalizing the No-U-Turn Sampler to LMC, we build the NUTS-LMC algorithm. The resulting algorithm is able to estimate the hyperparameters automatically. The NUTS algorithm is constructed with a distance based stopping criterion, which can be replaced by another stopping criteria. Additionally, we run LMC-Monge and NUTS-LMC for a series of traditionally challenging target distributions comparing the results with HMC and NUTS-HMC. The main contribution of this work is the extension of NUTS to generalized NUTS, which is applicable to LMC. It is found that LMC with Monge explores regions of target distribution which HMC is unable to. Furthermore, generalized NUTS eliminates the need to choose the hyperparameters. NUTS-LMC makes the sampler ready to use for scientific applications since the only need is to specify a twice differentiable target function, thus, making it user friendly for someone who does not wish to know the theoretical and technical details beneath the sampler.
  • Bohm, Katja (2018)
    Mid-Proterozoic mafic dyke swarms in southern Finland are associated with rapakivi magmatism. The dyke swarms are commonly referred to as “Subjotnian” (1.64–1.54 Ga), being older than the rift-filling Jotnian sandstones. Mafic rocks from five dyke swarms located in Åland, Satakunta, Häme, Suomenniemi and Sipoo were studied in this thesis. An X-ray fluorescence (XRF) analysis was made of 110 rock samples from 101 mafic dykes and one mafic intrusion. The analyses were made of the same rock samples as previous paleomagnetic studies. Overall, the Subjotnian mafic dykes in southern Finland are hyperstene-normative tholeiitic basalts or basaltic andesites with varying MgO contents (3–15 wt%). Some dykes show alkaline features with higher total alkali and/or Nb/Y values. They vary from quartz- to olivine-normative types. The dykes of the Åland swarm form two geohemical groups. The division is accompanied with a switch in magnetic polarity and distinct virtual geomagnetic pole positions. These observations imply that two separate magmatic events/pulses that have an age difference have taken place in Åland. The Satakunta dykes form two geochemical groups of which the other includes presumably Svecofennian dykes that show high Nb/Y values at given Zr/Y ratios. The dykes of the Häme swarm form three geochemical groups. Although some Suomenniemi dykes show geochemical and paleomagnetic affinities to Häme dykes, they probably represent a distinct igneous event of the event that formed the nearby Häme swarm. The Sipoo dykes are very homogeneous in their geochemistry and can be distinguished from the emplacement events that formed the other Subjotnian swarms. The Subjotnian dyke swarms in southern Finland that are believed to have emplacement ages of >1.63 Ga (Häme, Suomenniemi and Sipoo swarms in S-SE Finland) generally have higher Nb/Y (and Zr/Y) values than the dyke swarms that are believed to record younger magmatic events at <1.58 Ga (Åland and Satakunta swarms in SW Finland). Some Satakunta dykes, however, have geochemical and/or paleomagnetic implications that suggest they have an older Subjotnian age than the dated 1.57 Ga dyke in Satakunta. Further chronological work on the Satakunta dyke swarm is needed to verify the age of the dykes. Many of the Subjotnian dykes show a secondary magnetization component, called the “B-component”, whose direction is always close to, but distinct of, the Present Earth Field (PEF) at the sampling location. There was no correlation between the B-component and the magma types of the dykes. The B-component occurs mostly in dykes that are very altered. Thus, the results support previous suggestions that the B-component formed due to hydrothermal alteration of the rocks and the subsequent formation of new magnetic minerals.
  • Spehar, Mikael (2020)
    The oldest rocks in Finland are the Archaean grey gneisses of eastern and northern Finland. The Archaean of the Karelian craton spans about 1000 Ma of crustal growth and evolution and forms the core of the Fennoscandian shield. The Karelian province is a complex patchwork of different rock types. The individual formations are of small territorial extent in accordance with often postulated small Archaean plates. Overall, the Karelian craton is a granitoid-greenstone terrain with prevailing TTGs and younger granites, which show increasing level of potassium. The craton also includes a distinct sodic variety of granites that combines features of classical Archaean TTGs and late Archaean high-K granites. A minor number of Mg-rich lithologic units, including adakites and sanukitoids, are reported as well. A small number of A-type granites, syenites and S-type granites are widely distributed and of local nature only. Peculiarly, a large number of TTGs is peraluminous. The formation of Karelian craton may be explained by accretion of small plates, perhaps during the late Archaean supercraton event in a process that at least in later stages included active plate marginal processes.