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  • Tiittanen, Henri (2019)
    Estimating the error level of models is an important task in machine learning. If the data used is independent and identically distributed, as is usually assumed, there exist standard methods to estimate the error level. However, if the data distribution changes, i.e., a phenomenon known as concept drift occurs, those methods may not work properly anymore. Most existing methods for detecting concept drift focus on the case in which the ground truth values are immediately known. In practice, that is often not the case. Even when the ground truth is unknown, a certain type of concept drift called virtual concept drift can be detected. In this thesis we present a method called drifter for estimating the error level of arbitrary regres- sion functions when the ground truth is not known. Concept drift detection is a straightforward application of error level estimation. Error level based concept drift detection can be more useful than traditional approaches based on direct distribution comparison, since only changes that affect the error level are detected. In this work we describe the drifter algorithm in detail, including its theoretical basis, and present an experimental evaluation of its performance in virtual concept drift detection on multiple datasets consisting of both synthetic and real-world datasets and multiple regression functions. Our experi- ments show that the drifter algorithm can be used to detect virtual concept drift with a reasonable accuracy.
  • Helander, Riina (2019)
    Ruokaturvallisuuden merkitys korostuu tulevaisuudessa muun muassa ilmastonmuutoksen, kuluttajan toiveiden ja globalisaation myötä. Ammattikeittiöissä ruokaturvallisuus painottuu elintarvikehygieniaan ja sitä toteutetaan omavalvonnalla. Omavalvonnan kirjauksia, kuten lämpötilahallintaa, on perinteisesti tehty käsin paperille ja valvonnan mittaukset ovat olleet näytemittauksia jatkuvan valvonnan sijasta. Suomalaisissa ammattikeittiöissä omavalvonta toteutuu pääasiassa hyvin, mutta lainsäädännön tulkinta, resursointi ja epäyhtenäiset toimintatavat saattavat aiheuttaa haasteita. Ihmisen rooli ruokaturvallisuudessa on merkittävä. Tänä päivänä teknologian hyödyntäminen ruokaturvallisuudessa yleistyy ja uusia innovaatioita siihen kehitetään jatkuvasti. Omavalvonta voidaan digitalisoida ja automatisoida. Tämän tutkimuksen tavoitteena oli kehittää digitaalista omavalvonnan palvelua ruokaturvallisuutta edistävästi. Tutkimus oli laadullinen tutkimus, jossa menetelminä käytettiin puolistrukturoitua teemahaastattelua ja lyhyempää kyselyhaastattelua. Teemahaastattelujen haastateltavat olivat ammattikeittiöiden keittiöpäälliköitä tai ylemmän tason esimiehiä ja kyselyhaastatteluihin vastasi keittiöiden työntekijät ja kokit. Lisäksi haastateltiin neljää valvontaviranomaista. Teemahaastattelun teemoja olivat omavalvonnan merkitys, haasteet ja ajankäyttö, digitaalisen omavalvonnan vahvuudet, heikkoudet ja kehittäminen, palveluntarjoajan rooli sekä digitaalisen omavalvonnan vaikutus ruokaturvallisuuteen. Valvontaviranomaisilla teemana oli myös valvontakäynnit. Nauhoitetut aineistot litteroitiin ja analysoitiin sisällönanalyysilla teemoitellen. Haasteita omavalvonnassa tuottivat resursointi, lainsäädännön tulkinta sekä eri tasoinen osaaminen niin ruokaturvallisuudesta kuin digitaalisista työvälineistä. Digitaalinen omavalvonta lisäsi haastateltavien mielestä ruokaturvallisuutta automaattisen lämpötilaseurannan, läpinäkyvyyden ja sitouttamisen myötä. Digitaalista omavalvontaa tulisi kehittää kahdesta näkökulmasta. Ensinnäkin, digitaalisten työvälineiden tulisi ohjata käyttäjää tekemään ruokaturvallisia ratkaisuja, perehdyttää, motivoida ja sitä kautta sitouttaa paremmin omavalvonnan tekemiseen. Toiseksi, teknologian ratkaisuja ja automatisointia tulisi lisätä laajemmin koko omavalvontaan. Eri keittiöiden eri prosessit ja sitä kautta omavalvonnan toimintamallit tulee huomioida kehityksessä.
  • Vidén, Henna (2020)
    Euroopan unionin sisämarkkinat mahdollistavat tavaroiden, palvelujen, henkilöiden ja pääoman vapaan liikkuvuuden. Yhä suurempi joukko ammattihenkilöitä hyödyntää sisämarkkinoiden vapaata liikkuvuutta harjoittaakseen ammattiaan toisessa jäsenvaltiossa joko pysyvästi tai tarjotakseen palveluitaan väliaikaisesti ja satunnaisesti. Vaikka kyse on jatkuvasti kasvavasta ilmiöstä, ammattipätevyyden tunnustamista koskevaa oikeustieteellistä tutkimusta ei ole kattavasti tehty. Tämän lainopillisen tutkielman tarkoituksena on ollut vastata tähän puutteeseen luomalla yleiskäsitys siitä, miten ammattipätevyyden tunnustamista säännellään EU-oikeudessa. Tutkimusteemaa on lähestytty ensin luomalla katsaus ammattipätevyyden tunnustamisen historiaan ja siihen, miten sisämarkkinat ja ammattipätevyyden tunnustamista koskeva sekundaarinormisto ovat kehittyneet. Erityisesti unionin tuomioistuimen oikeuskäytännössä syntynyt vastavuoroisen tunnustamisen periaate on vaikuttanut merkittävällä tavalla tutkintotodistusten, tutkintojen ja muiden muodollista pätevyyttä osoittavien asiakirjojen vastavuoroiseen tunnustamiseen ja sitä voidaankin pitää ammattipätevyyden tunnustamisen perustana. Tämä kehitys on johtanut voimassa olevan ammattipätevyysdirektiivin syntymiseen, joka on keskeisin ammattipätevyyden tunnustamista sääntelevä EU-oikeuden instrumentti. Tutkielmassa on keskitytty ennen kaikkea ammattipätevyysdirektiivin keskeisen sisällön käsittelyyn, minkä lisäksi tutkielmassa on nostettu esiin siihen liittyviä haasteita. Ammattipätevyyden tunnustaminen perustuu oletukseen siitä, että ammattihenkilöt voivat hyödyntää perussopimuksen turvaamia perusvapauksiaan. Unionin perusvapaudet eivät kuitenkaan ole luonteeltaan absoluuttisia, sillä niitä voidaan rajoittaa perussopimuksen tunnustamilla rajoitusperusteilla sekä unionin tuomioistuimen oikeuskäytännössä syntyneillä, yleiseen etuun liittyvillä pakottavilla vaatimuksilla. Tutkielmassa on arvioitu näitä rajoitusperusteita unionin lainsäädännön ja oikeuskäytännön valossa. Tutkielman lopuksi on vastattu tutkielman alussa esitettyihin kysymyksiin ja arvioitu tutkielmassa tehtyjä havaintoja erityisesti oikeusvarmuuden näkökulmasta sekä pohdittu ammattipätevyyden tunnustamiseen liittyviä tulevaisuuden näkymiä.
  • Rehn, Aki (2022)
    The application of Gaussian processes (GPs) is limited by the rather slow process of optimizing the hyperparameters of a GP kernel which causes problems especially in applications -- such as Bayesian optimization -- that involve repeated optimization of the kernel hyperparameters. Recently, the issue was addressed by a method that "amortizes" the inference of the hyperparameters using a hierarchical neural network architecture to predict the GP hyperparameters from data; the model is trained on a synthetic GP dataset and in general does not require retraining for unseen data. We asked if we can understand the method well enough to replicate it with a squared exponential kernel with automatic relevance determination (SE-ARD). We also asked if it is feasible to extend the system to predict posterior approximations instead of point-estimates to support fully Bayesian GPs. We introduce the theory behind Bayesian inference; gradient-based optimization; Gaussian process regression; variational inference; neural networks and the transformer architecture; the method that predicts point-estimates of the hyperparameters; and finally our proposed architecture to extend the method to a variational inference framework. We were able to successfully replicate the method from scratch with an SE-ARD kernel. In our experiments, we show that our replicated version of the method works and gives good results. We also implemented the proposed extension of the method to a variational inference framework. In our experiments, we do not find concrete reasons that would prevent the model from functioning, but observe that the model is very difficult to train. The final model that we were able to train predicted good means for (Gaussian) posterior approximations, but the variances that the model predicted were abnormally large. We analyze possible causes and suggest future work.
  • Korhonen, Laura Sofia Katariina (2023)
    In this sociolinguistic study that applies multimodal critical discourse analysis (MCDA) methods the aim was to examine what kinds of ideas of health are expressed in the American dietary guidelines and what kind of health discourse these ideas are a part of. Based on Machin and Mayr’s (2012) ideas on semiotic resources, linguistic and visual patterns, that can communicate ideas, ideologies, power patterns, attitudes and other messages, the study focuses on ten pages of the Dietary Guidelines for Americans, 2020-2025. The expressed sentence structures and word choices, among other visual and linguistic factors, are evaluated, and then connected to the sociocultural background. This qualitative sociolinguistic study found that through the choices the authors and other creators of the U.S. dietary guidelines report 2020-2025 have made, the Guidelines express neoliberal health views and contribute to health discourse that has the potential to sustain similar views. Linguistic and visual analysis concludes that especially the individual’s responsibility and freedom are underlined in the Guidelines’ language and content. The analysis also notes the contrasting expression of the role of the environmental factors, such as the food and retail establishments and manufacturers, and the multimodal aspects that in addition to the neoliberal discourse of health express other discourses of health.
  • Pensola, Annika (2022)
    This qualitative study examines multimodal storytelling in online corporate stories. Corporate stories are realized in a particular genre, the About page, and moral discourse is conveyed through references to Corporate Social Responsibility (CSR). To examine how CSR has been incorporated into corporate storytelling and how it functions within the About page, the study begins with an examination of the About page as a genre. The research data consists of stories from five Finnish companies working in the textile and apparel industry: Aarre, Vimma, Kaiko, Uhana, and Pure Waste. The companies were chosen as they share similarities regarding multiple aspects (e.g., company size, product range, and target audience). The stories were firstly analyzed for their schematic components and expressive resources (Bateman 2008, 2014), and then further subjected to critical multimodal discourse analysis (Machin and Mayr 2012) to critically examine the expressive forms used in the components. Although the layout structure varied among the stories of the data, the presence of several schematic components was constant in all stories. Based on the current analysis, the components which were present in most of the stories constitute the core components of the genre of About page: mission, essence, founder(s), foundation, products, production, and social responsibility. The analysis revealed that not only is CSR present on the pages as its own schematic component, but direct and indirect references to CSR themes were used as justification and motivation within other schematic components as well, thus framing CSR as an essential component of the corporate identity. These corporate stories cater to the consumer narrative in which social responsibility plays a central role by establishing an environment in which one can keep on purchasing new clothes while adhering to those values. The products are laden with socially responsible attributes, framing social responsibility as a fashion statement.
  • Comănescu, Andrei-Daniel (2020)
    Social networks represent a public forum of discussion for various topics, some of them controversial. Twitter is such a social network; it acts as a public space where discourse occurs. In recent years the role of social networks in information spreading has increased. As have the fears regarding the increasingly polarised discourse on social networks, caused by the tendency of users to avoid exposure to opposing opinions, while increasingly interacting with only like-minded individuals. This work looks at controversial topics on Twitter, over a long period of time, through the prism of political polarisation. We use the daily interactions, and the underlying structure of the whole conversation, to create daily graphs that are then used to obtain daily graph embeddings. We estimate the political ideologies of the users that are represented in the graph embeddings. By using the political ideologies of users and the daily graph embeddings, we offer a series of methods that allow us to detect and analyse changes in the political polarisation of the conversation. This enables us to conclude that, during our analysed time period, the overall polarisation levels for our examined controversial topics have stagnated. We also explore the effects of topic-related controversial events on the conversation, thus revealing their short-term effect on the conversation as a whole. Additionally, the linkage between increased interest in a topic and the increase of political polarisation is explored. Our findings reveal that as the interest in the controversial topic increases, so does the political polarisation.
  • Raivio, Ville (2020)
    Tämä englanninkielinen tutkielma analysoi retoriikkaa Winston Churchillin ja Barack Obaman poliittisissa puheissa. Tutkielma esittelee kahden poliitikon tavat kirjoittaa puheita ja heille ominaiset puhetyylin keinot, sekä analysoi kolme puhetta molemmilta. Tutkielma sisältää johdannon, teoreettisen kirjallisuuden esittelyn, Churchillin sekä Obaman lyhyet elämäkerrat, poliitikkojen puhetyylin ja puheiden kirjoitustapojen esittelyt, kolmen puheen analyysin molemmilta puhujilta sekä yhteenvedon. Tutkielman liitteenä on puheet, joita työssä analysoidaan. Tutkielma esittelee myös molempien poliitikkojen uskonnollisen taustan. Työn teoreettinen aineisto pohjautuu antiikin Kreikan aikaiseen Aristoteleen Retoriikka-teokseen sekä antiikin Rooman aikaiseen tuntemattoman kirjoittajan puheoppaseen Rhetorica ad Herennium. Nämä teokset ovat tärkeimmät retoriikasta laaditut oppaat, joiden teorioihin myöhempien aikakausien kirjat pohjautuvat. Muu aineisto koostuu teoksista, jotka esittelevät poliitikkojen elämäkertoja, heidän puhetapojaan sekä retoriikan termistöä. Puheiden analysoinnissa metodina on kirjallisuustutkimuksen määrittelemä lähiluku. Aineiston kautta selviää, että Winston Churchill ja Barack Obama kirjoittivat puheensa itse uransa alkuvaiheessa, mutta presidentin ja pääministerin asemassa heidän aikansa ei enää riittänyt tähän. Puheissaan Churchill personifioi maita ja hän viittasi Liittoutuneiden ja natsi-Saksan vastaiseen sotaan hyvän ja pahan taisteluna. Hänen puhetyylinsä oli pessimistinen ja pääministeri lupasi kärsimyksiä sekä tuhoa vuodesta toiseen. Barack Obaman puhetyyliin kuuluvat parafraasit, somaattiset fraasit sekä sananlaskut, hänen puheidensa yleinen teema on amerikkalainen unelma. Analyysin tuloksena selviää, että Churchill ja Obama pyrkivät vaikuttamaan kuulijan tunteisiin ennen kaikkea kristillisten kielikuvien ja viitteiden kautta. Tutkielman johtopäätöksenä on, että molemmat poliitikot ovat käyttäneet klassisen retoriikan metodeja puheissaan, lisäksi molemmat ovat käyttäneet kristinuskon sanastoa ja kuvastoa vaikuttaakseen kuulijoihin. Jokaisessa aineiston kuudesta puheesta on kristillisiä käsitteitä, jotka yhdistävät suurinta osaa Yhdysvaltojen ja Iso-Britannian kansalaisista. Jatkotutkimusta varten olisi hyödyllistä laajentaa Churchillin ja Obaman puheiden aineistoa ja lähilukua käyttäen tutkia, millä tavoin poliitikot ovat käyttäneet kristinuskon teemoja vaikuttaakseen kuulijoihinsa. Tämä selventäisi uskon asemaa kahden vaikutusvaltaisen länsimaisen poliitikon retoriikassa ja osana yhteiskunnallista diskurssia.
  • Hakomäki, Stina (2023)
    This dissertation is a thematic analysis of the concept of gender in the European Union’s Gender Action Plan III. The Gender Action Plan III (GAP III) is the European Union’s action plan on gender equality and women's empowerment (European Commission 2020). I argue that as a Gender Action Plan, gender is a crucial concept of said action plan and as such should be clearly defined. I further argue that gender should not be limited to women and men. I use thematic analysis and Feminist Critical Discourse Analysis to analyse the language and the meaning of the language that deals with gender (equality) in the GAP III. The theoretical framework of this dissertation consists of the theory and literature on Feminist Foreign Policy (FFP). FFP literature is useful because the GAP III can be analysed (and criticised) over a lot of the same themes as governmental feminist foreign policies (Aggestam & Bergman Rosamond 2018; Bernarding & Lunz 2020; Scheyer & Kumskova 2019). These themes include for instance: the concept of gender and militarism (Ibid.). FFP theory and literature aids me in finding relevant themes and issues in the GAP III. As I analyse the concept of gender in the GAP III, I find that it is defined rather insufficiently. I find that it is often reduced to women and girls. I conclude that the GAP III begins with gender but ends up with women and girls.
  • Grönfors, Helle (2023)
    The literature review focused on liquid chromatographic-mass spectrometric (LC-MS) methods used to quantify B12 vitamers in food matrices. Various MS methods have been used for the detection of B12, offering more specificity than other commonly used analysis techniques. This thesis aimed to develop a method for quantifying the native forms of B12 in different food matrices and avoiding the commonly used conversion to cyanocobalamin during extraction. In the experimental study, an ultra-high-performance LC-tandem MS (UHPLC-MS/MS) method was developed and validated for selectivity, specificity, recovery, repeatability, reproducibility, trueness, and measurement uncertainty to determine B12 vitamers in fermented plant-based foods and microbial cell supernatants. The development was initiated by setting up mass spectrometer conditions and selecting transitions for multiple reaction monitoring (MRM) to achieve selective and sensitive detection method for individual B12 vitamers. This was followed by developing the UHPLC method utilizing a reversed-phased C18 column and gradient elution with 0.5% formic acid and 0.5% FA in methanol. The vitamers were ionized using electrospray ionization in a positive ion mode and detected in an MRM mode using hydroxocobalamin, cyanocobalamin, adenosylcobalamin, and methylcobalamin. All B12 vitamers were detected and separated with the developed and optimized UHPLC-MS/MS method. The internal standard calibration method was necessary to overcome matrix effects when analyzing food samples. The calibration curve content range was 0.2–200 pg/µL, and the results showed good linearity. The instrumental method was selective, precise, repeatable, and reproducible with detection and quantitation limits of 0.03–0.4 pg/µL and 0.2–2 pg/µL, respectively. The measurement uncertainty of the instrumental method varied between 10% and 20%. For the entire method, recoveries for the B12 vitamers ranged from 40% to 200%, and measurement uncertainties from 40% to 60%. Results for the total B12 content in food samples deviated from those determined using a conventional UHPLC-PDA method: Recovery for tempeh was over 90%, but for fortified bread only 20%. These results indicate the need for further development of sample pretreatment. The instrumental method was successfully validated and separated matrix compounds from B12 vitamers in food samples to some extent. The developed sample pretreatment method is a good starting point for developing more effective sample pretreatment methods in the future.
  • Li, Yanru (2022)
    Phage lysins are enzymes that degrade bacterial cell wall. A wild-type Lactococcus lactis strain LAC460 secretes three phage lysins, LysL, LysP, and LysT, encoded by three different prophages. Unlike common phage lysins, these enzymes do not break down the host's cell wall. Therefore, these lysins can attack other L. lactis strains and behave like bacteriocins, antimicrobial proteins. The binding of a phage lysin to bacterial cell wall requires a specific cell wall binding domain (CBD) in the lysin. However, nothing about the CBDs of LysL, LysP and LysT is known. This study aimed to determine the CBDs of these three lysins and the target specificity of the lysins. Putative CBD regions of the lysins were fused with green fluorescent protein (GFPuv). GFPuv-CBD-LysL and GFPuv-CBD-LysT were ligated into the pASG-IBA4 vector and cloned in Escherichia coli DH5α. After all, only the construction of the GFPuv-CBD- LysL was successful resulting in fluorescent transformants. To analyse the binding of GFPuv- CBD-LysL to cells of different L. lactis strains, the fusion proteins were mixed with the LysL sensitive L. lactis MG1614, LysL resistant L. lactis LM0230, and the LysL producing LAC460 cells. With fluorescence microscope it could be seen that the GFPuv-CBD-LysL decorated the cell surface of L. lactis MG1614 with green fluorescence, but LM0230 and LAC460 cells remained non-fluorescent. The fluorescence of the cells was also measured with a fluorometer, showing strong fluorescence from MG1614, but nothing from the other two strains. This showed that the fusion protein specifically bound to the MG1614 cell surface, but it did not bind to the LysL resistant strain LM0230 or the LysL producer LAC460 cell. In conclusion, the results demonstrate that the C-terminus of LysL contains a specific cell wall binding domain. In addition, the results provide an explanation for how LAC460 can secrete LysL without autolysis, as phage lysins not able to bind onto peptidoglycan are unable to lyse cells.
  • Katajisto, Paula (2022)
    The research focuses on the productive e-learning exercises in upper secondary school English learning materials provided by four publishers in their e-textbooks. Digital learning materials have become increasingly common, and the introduction of the new National Core Curriculum for general upper secondary schools has prompted publishing houses to publish new materials, with an even bigger focus on the digital version. The aim of this study is to provide a comprehensive description and a critical evaluation of the variety of productive e-learning exercises that the publishers provide. Previous research on this topic in the Finnish context is very limited and learning materials in general have mostly been studied by master’s students in universities. The materials for the analysis come from the productive e-learning exercises that are related to text chapters in the four publishers’ (Sanoma Pro, Otava, Edita, and Studeo) e-textbooks. All the analysed materials are brand new and have not been researched before. The research method for this study is content analysis, which is conducted through both quantitative and qualitative methods. The analysis was conducted by coding the data based on three main categories that are What is the learner expected to do?, Who with?, and With what content?, and in several subcategories under them. The findings show that the available published materials provide a wide variety of different e-learning exercises for the upper secondary school students. Most often the results of the comparative analyses showed similarities, rather than dramatic differences between the four publishers’ materials. With regards to the four characteristics of learning, the results of the study showed that one of them was supported especially well (students’ activity and initiative), two were supported well (sense of community and clear, authentic, and demanding exercises), and only one characteristic was not supported well enough (learning skills) by the analysed e-learning exercises. The current study provides useful data for the, still lacking, learning material research in the Finnish context. The presented findings give insight to the publishers into what factors should be considered when designing exercises for new products. For teachers, the findings can be useful when making use of one of the e-textbooks in the classroom, whilst planning lessons and courses, or when choosing which publisher’s material they would like to use next.
  • Heiskanen, Ilmari (2021)
    Interest towards indoor air quality has increased for several decades from human health perspective. In order to evaluate the quality of indoor air in terms of volatile organic compound (VOC) levels, robust analytical procedures and techniques must be used for indoor air VOC measurements. Since indoor building materials are the greatest source of indoor VOC emissions, same kind of procedures must be used for analysis of emission rates from building materials and their surfaces. Theory part of this thesis reviews background of VOCs and human health, legislation and guideline values, common building materials with emissions and used sampling techniques/approaches for indoor air sampling and surface material emission rate sampling & analysis. Discussed sampling techniques include, for example, material emission test chambers, field and laboratory test emission cells, solid phase microextraction (SPME) fibre applications and Radiello passive samplers. Also new innovative approaches are discussed. Used common analysis instruments are Gas Chromatography (GC) with Mass Spectrometer (MS) or Flame Ionization Detector (FID) for VOCs and High-Performance Liquid Chromatography-Ultraviolet/Visible light detector (HPLC-UV/VIS) for carbonyl VOCs (e.g. formaldehyde) after suitable derivatization. Analytical procedures remain highly ISO 16000 standard series orientated even in recent studies. In addition, potential usage of new modern miniaturized sample collection devices SPME Arrow and In-tube extraction (ITEX) used in experimental part of this thesis are discussed as an addition to indoor air and VOC emission studies. The aim of the experimental part of this thesis was to develop calibrations for selected organic nitrogen compounds with SPME Arrow and ITEX sampling techniques and test the calibration with indoor and outdoor samples. A calibration was successfully carried out with SPME Arrow (MCM-41 sorbent), ITEX (MCM-TP sorbent) and ITEX (Polyacrylonitrile (PAN) 10 % sorbent) with permeation system combined with GC-MS for the following selected organic nitrogen compounds: triethylamine, pyridine, isobutyl amine, allylamine, trimethylamine, ethylenediamine, dipropyl amine, hexylamine, 1,3-diaminopropane, 1-methyl-imidazole, N, N-dimethylformamide, 1,2-diaminocyclohexane, 1-nitropropane and formamide. The overall quality of the calibration curves was evaluated, and the calibrations were compared in terms of linear range, relative standard deviation (RSD) % for accepted calibration levels and obtained Limits of Detection (LOD) values. Also, ways to improve the calibrations were discussed. The calibration curves were tested with real indoor and outdoor samples and quantitative, as well as semi-quantitative, results were obtained.
  • Kivinen, Anssi (2020)
    The analysis of volatile organics is growing by the year and there is a great interest in fast and simple sample preparation techniques. With solid phase micro-extraction, samples can be extracted non-destructively without a need for solvents. This is both cost effective and ecological, because even most eco-friendly solvents still cause strain on the environment. This thesis focused on studying the effect of extraction conditions on the extraction efficiency. The effect of different sorptive phase materials was tested as well. New single-step sample extraction and preparation method was developed for gas chromatographic mass spectrometric analysis. Three different sorptive phase materials were compared and the extraction conditions were optimized for each. The method developed was used to extract, analyze and determine unknown compounds from a butterfly specimen. Multiple extractions were performed from both headspace and with direct immersion. By progressively changing the extraction conditions, properties of the compounds such as volatility and polarity could be determined by their presence alone. Analysis was performed using with gas chromatography mass-spectrometer using electron ionization quadrupole mass detector in full scan mode.
  • Yassami, Shiva (2022)
    Saccharomyces boulardii is a probiotic yeast related to Saccharomyces cerevisiae but with distinct genetic, taxonomic, and metabolic properties. S. cerevisiae has been used extensively in biotechnological applications. Currently, many strains are available, and multiple genetic tools have been developed, which allow the expression of several exogenous proteins of interest with applications in the fields of medicine, biofuels, the food industry, and scientific research, among others. Although S. boulardii has been widely studied due to its probiotic properties against several gastrointestinal tract disorders, very few studies addressed the use of this yeast as a vector for expression of foreign genes of interest with biotechnological applications. I studied the previously constructed S. boulardii SAC12, which secretes the anti-listerial bacteriocin leucocin C originating from Leuconostoc carnosum 4010. The objective was to study if the bacteriocin leucocin C producing S. boulardii could produce leucocin C in beer fermentation and if leucocin C containing beer can be used as marinade to control Listeria monocytogenes in raw chicken breast strips. The results showed that SAC12 has good ability to secrete LecC, and thus it was used to brew anti-listerial beer. According to results, beer could maintain its anti-listerial activity for 38 days. The anti-listerial effect of the beer stored for different times was analyzed through marinating chicken breast strips (spiked with L. monocytogenes) with the beer for overnight. Results indicated a positive impact of anti-listerial beer in reduction of the viable cells of L. monocytogenes by about 1.6 log from (2.2 ± 0.6) × 10⁷ CFU/g (beer from day 24), and 2.2 log from (1.8 ± 0.3) × 10⁵ CFU/g (beer from day 38). To sum up, the S. boulardii SAC12 efficiently secreted the bacteriocin leucocin C. Brewing beer with S. boulardii SAC12 resulted in beer containing leucocin C. Such beer showed anti-listerial effect when used as marinade for chicken breast strips.
  • Haajanen, Hanna (2020)
    3-Chloro-1,2-propanediol (3-MCPD), 2-chloro-1,3-propanediol (2-MCPD) and 2,3-epoxy-1-propanol (glycidol) and their fatty acid esters are contaminants formed during processing fat containing foodstuffs at high temperatures. Mainly MCPD and glycidyl esters have been found to be formed in the deodorization process of oils, and in vegetable oils, such as palm oil, they have been measured at high concentrations. In accordance with the restrictions imposed by the European Commission, the levels of glycidyl esters must be especially monitored, as they have been identified as potentially carcinogenic compounds. The aim of the study was to introduce and validate a gas chromatographic analysis method for glycidyl esters and MCPD esters for the Customs Laboratory. The method was validated for two matrices: first for oils and then for powdered infant formulas. In addition, the success of the validation was examined by analyzing various oil samples previously received by the Customs Laboratory. The Customs Laboratory is also involved in the activities of the European Union Reference Laboratory, for which it was intended to participate in the reference measurement organized by the EU Reference Laboratory. The method for the determination of 3-MCPD, 2-MCPD and glycidyl esters in oils and infant formulas was carried out according to the guidelines of the European Union Reference Laboratory for Contaminants (EURL-PC). Determination of MCPD and glycidyl ester concentrations in oils and infant formulas included the following steps: fat extraction by liquid-liquid extraction (for infant formulas), addition of standards, solid-phase extraction, conversion of glycidyl esters to 3-MBPD esters, transesterification, neutralization, salting out, derivatization and analysis with gas chromatography-mass spectrometry system. Concentrations were determined using internal standard method. The method was validated for the following parameters: specificity, selectivity, limit of detection and quantitation, reproducibility, repeatability, trueness, linearity and working range, stability and measurement uncertainty. The analytical method developed for the determination of MCPD and glycidyl esters was successfully validated for oils and powdered infant formulas. The developed method proved to be specific and selective. The limit of determination was found to be 6.3 µg/kg, 1.3 µg/kg and 0.8 µg/kg for the oil matrix 3-MCPD, 2-MCPD and glycidyl esters. The limits of determination for the infant formula were 5.4 µg/kg, 3.0 µg/kg and 1.6 µg/kg for 3-MCPD, 2-MCPD and glycidyl esters. Recoveries for MCPD and glycidyl esters in the oil and powdered infant formulas were 83-105%. R2 for calibration lines were greater than 0.99, and the lines were linear over the entire measurement range of 2-1000 µg/kg. The relative standard deviation of repeatability and reproducibility was less than 20% for both matrices. The expanded measurement uncertainty for the MCPD and glycidyl esters of the oil and powdered infant formula was less than 50%. For all parameters, the requirements set by the Customs Laboratory and the performance requirements of Regulation (EU) 1881/2006 were met. A method validated for two matrices can then be accredited. The customs laboratory may use the developed method in the future to control 3-MCPD, 2-MCPD and glycidyl esters levels of oils and powdered infant formulas. In the future, the method could also be validated for new matrices, such as liquid infant formulas.
  • Louhi, Jarkko (2023)
    The rapid growth of artificial intelligence (AI) and machine learning (ML) solutions has created a need to develop, deploy and maintain AI/ML those to production reliably and efficiently. MLOps (Machine Learning Operations) framework is a collection of tools and practices that aims to address this challenge. Within the MLOps framework, a concept called the feature store is introduced, serving as a central repository responsible for storing, managing, and facilitating the sharing and reuse of extracted features derived from raw data. This study gives first an overview of the MLOps framework and delves deeper into feature engineering and feature data management, and explores the challenges related to these processes. Further, feature stores are presented, what they exactly are and what benefits do they introduce to organizations and companies developing ML solutions. The study also reviews some of the currently popular feature store tools. The primary goal of this study is to provide recommendations for organizations to leverage feature stores as a solution to the challenges they encounter in managing feature data currently. Through an analysis of the current state-of-the-art and a comprehensive study of organizations' practices and challenges, this research presents key insights into the benefits of feature stores in the context of MLOps. Overall, the thesis highlights the potential of feature stores as a valuable tool for organizations seeking to optimize their ML practices and achieve a competitive advantage in today's data-driven landscape. The research aims to explore and gather practitioners' experiences and opinions on the aforementioned topics through interviews conducted with experts from Finnish organizations.
  • Armijos, Jacqueline (2023)
    This thesis analyses COVID-19 vaccine discourse in online news in December 2022 by applying APPRAISAL, in particular, the APPRECIATION subsystem, and corpus-based methods such as frequency, keyword, and concordance line. The analysis addresses three research questions based on a dataset of 599 concordance lines, from the Coronavirus corpus representing twenty English speaking countries. The study identifies the top twenty adjectives associated with COVID-19 vaccines, classifying them into four main categories according to their social value and particular characteristics. The main findings show that positive attitudes emerge through interpersonal meaning in online news. Mainly, journalists portray the vaccine discourse under WHO’s ideology, hoping for a ‘New normality’. On the other hand, negative attitudes showcased challenges and controversies. Hence, the study emphasizes the importance of shaping public health communication and opinions built on transparent scientific and consensual information. That is the study stresses the value of providing the public with accurate and well-supported information to shape a better understanding and opinions related to health concerns. Finally, the methodological contribution suggests implementing uniqueness as a new subcategory, but the existing subcategory, balance, deserves more attention whether to implement it or not in future studies. The study also highlights the impact of political ideologies on COVID-19 vaccine discourse, and thus recommends future research on attitudes in non-English-languages areas.
  • Leskelä, Laura (2021)
    Physical and social anhedonia have shown some promise as possible indicators of later mental illness, especially of depression and schizophrenia. However, previous studies have focused on college students and clinical populations, limiting their generalizability into the whole population. Most previous studies have also been cross-sectional. The aim of this longitudinal study with a general population sample is to examine whether high social or physical anhedonia in young adulthood precedes later psychiatric diagnoses. In addition, cross-sectional connections between demographic factors (sex, age, marital status, education) and social and physical anhedonia were examined. The study sample (n=453) of young adults was recruited through the Health 2000 study, which is a representative sample of the adult Finnish population. In the beginning of the study, participants filled in the self-report Chapman Revised Anhedonia Scales, and their demographic factors were clarified using a questionnaire (marital status, education level) and health records (age, sex). After this there was a follow-up period of 9 to 12 years. The psychiatric diagnoses of the participants from the follow-up period were retrieved from the Finnish Hospital Discharge Register, which includes both inpatient and outpatient specialized psychiatric care. Two sets of analyses were done: analyses of variance (ANOVA) examining the cross-sectional associations between anhedonia and demographic factors (age, sex, marital status, education) and Cox regression analyses examining longitudinal associations between aforementioned variables and later psychiatric diagnoses. Male sex was associated with both higher physical and higher social anhedonia. 63 participants (13%) received at least one psychiatric diagnosis during the follow-up period. Three diagnostic groups were examined; one for receiving a depression diagnosis, one for receiving any anxiety diagnosis and one for receiving any psychiatric diagnosis. Physical or social anhedonia during young adulthood was not found to be associated with later psychiatric diagnoses. Instead, lack of marriage/cohabitation and female sex were found to be possible risk factors for receiving a diagnosis. Contrary to the hypotheses of this study, no association between anhedonia and later psychiatric diagnoses were found. However, the relatively small amount of diagnoses during the follow-up period restricted the statistical strength of the results. The results of this study suggest that anhedonia is not a major predictor of for receiving a later depression diagnosis, any anxiety diagnosis or any psychiatric diagnosis in the general young adult population.
  • Absetz, Maija (2019)
    Käsittelen valtaeliitin oikeudenmukaisuuskäsityksiä vuoden 1984 työttömyysturvalaista. Sosiaaliturvan eriarvoistavia vaikutuksia ennen 1990-luvun lamaa käsitteleviä tutkimuksia on tehty vain vähän, joten tämä tutkimus lisää tietoa jo 1980-luvulla tapahtuneesta sosiaaliturvasta johtuneesta eriarvoistumisesta. Tarkastelen ajanjakson valtaeliitin osapuolten välisiä suhteita ja vallan jakautumista. Lisäksi analysoin ja arvoin valtaeliitin osapuolien perusteluja oikeudenmukaiseen työttömyysturvaan. Arvioin työttömien oikeuksien ja velvollisuuksien muutoksia verrattuna edelliseen vuonna 1971 laadittuun työttömiä koskevaan lainsäädäntöön. Perustelen kuinka vuoden 1984 työttömyysturvauudistuksella oli työttömien oikeuksia heikentäviä vaikutuksia. Valtaeliitti tutkimuksessani tarkoittaa työmarkkinoiden keskusjärjestöjä (Suomen Työnantajien Keskusliitto, Suomen Ammattiliittojen Keskusjärjestö) sekä parlamentaarisen lainsäädäntöprosessin virallisia osapuolia eli hallitusta ja eduskuntaa. Aineistona käytän aiheeni kannalta oleellisia lainsäädäntöprosessissa laadittuja asiakirjoja: päälähteinäni ovat työttömyysturvakomiteanmietinnöt, vuoden 1984 hallituksen esitys työttömyysturvalaiksi ja vuoden 1984 valtiopäivämietintöjä. Lisäksi täydennän aineistoani Helsingin Sanomien uutisoinnin ja työmarkkinajärjestöjen pöytäkirjojen avulla. Analysoin tutkimuskirjallisuutta ja alkuperäislähteitä lähdekritiikin, triangulaation ja hermeneutiikan keinoin. Aineiston perusteella voidaan osoittaa, että työmarkkinajärjestöt vaikuttivat lainsäädäntöprosessiin. Työmarkkinajärjestöjen ja Suomen Sosialidemokraattisen Puolueen tukema työttömyysturvauudistus vahvisti työttömyysturvan ansiosidonnaisuutta ja lisäsi työttömyysturvan tasoeroja työttömien välillä. Ansiosidonnaisuutta voimistettiin, vaikka hallituksen enemmistö ja osa oppositiosta olisi halunnut luopua ansioturvajärjestelmästä ja siirtyä kaikille kuuluvaan perusturvaan. Kaikkien työttömien työttömyysturvan tasoa nostettiin, mutta ammattiliittojen työttömyyskassojen hallinnoiman ansioturvaan oikeutettujen lyhyen aikaa työttömänä olleiden perheellisten työttömien työttömyysturvaa nostettiin kaikista eniten. Työttömien väliset tuloerot kasvoivat sekä perusturvan ja ansioturvan välillä että ansioturvan sisällä, mutta työttömien ja palkansaajien välinen taloudellinen kuilu kapeni. Uusien työttömien ryhmien (yrittäjät, osa-aikatyöntekijät) oikeudet olivat muita ryhmiä heikompia. Tarveharkinnasta ei luovuttu, vaikka käytäntöä pidettiin epäoikeudenmukaisena. Työttömyysturvauudistus perustui yhä oletukseen kokoaikatyöstä, jossa työttömyysjaksot selitettiin katkoksina työurassa. Työttömyyden syiden selittämisessä keskityttiin työttömän vaikutukseen omaan työttömyyteensä ennemmin kuin työttömyyden rakenteellisiin syihin. Työttömien oikeuksia kavennettiin suhteessa vanhaan lainsäädäntöön. Työttömyysturvassa siirryttiin aiempaa velvoittavampaan tulkintaan alueellisesta liikkuvuudesta, ammattisuojan kesto yhtenäistettiin lyhyemmän keston mukaisesti ja uusia karensseja laadittiin työttömien aktiivisen työn vastaanottamisen varmistamiseksi. Tutkimus antaa viitteitä siitä, että sosiaaliturvaa kiristettiin jo talouden nousukaudella, vaikka leikkaukset työttömyysturvaan tehtiin vasta 1990-luvulla. Sosiaaliturvan kiristävää vaikutusta voisi tutkia vielä monipuolisemmin kuin vain työttömyysturvan osalta. Vuoden 1984 työttömyysturvauudistuksesta olisi perusteltua myös tutkia lainsäätäjien taloususkomuksia. Jatkotutkimuksessa tulisi selvittää Suomen asema verrattuna 1980- luvun kansainvälisen sosiaaliturvan ja talouskasvun keskinäiseen suhteeseen.