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Atomic layer deposition (ALD) is a promising processing method for the next generation semiconductor devices. Major advantages of ALD include conformality, uniformity over large areas, precise thickness control, repeatability and high quality of films produced. ALD thin film deposition is done inside an ALD reactor. Typical construction materials of ALD reactors include metal alloys such as stainless steel, aluminum and titanium. These materials contain multiple metallic elements that can be detrimental to the performance, reliability and yield of semiconductor devices. In order to process semiconductor devices with ALD, metal impurity levels originating from the ALD reactor must be controlled. Allowed levels of metal impurities in semiconductor processing are stringent and showing a tightening trend. This has led into the development of new methods for contamination control together with the adoption of more sensitive and robust detection methods for metallic impurities, such as inductively coupled plasma mass spectrometry (ICP-MS). This master thesis focuses on the metallic impurities originating from an ALD reactor and their prevention with ALD coatings. Three typical construction materials, aluminum, titanium and stainless steel were examined. The studied coatings were ALD deposited aluminum oxide (Al2O3), hafnium oxide (HfO2) and their nanolaminate (Al2O3/HfO2). The ability of the coatings to prevent metal impurity transfer from the metals to silicon substrates through the gas phase was studied by exposing the coated metals to two ALD precursors, trimethyl aluminum (TMA) and tris(dimethylamino) cyclopentadienyl hafnium (CpHf(NMe2)3). Metal impurity concentrations on silicon were measured with ICP-MS. Since academic literature concerning control of metal contamination from ALD reactors does not directly exist, the literature part of this thesis was based on relevant related topics. The selected topics included the development of semiconductor industry, role of ALD in this development and new ALD materials and chemistries required. Additionally, protective ALD films and the effects of metal impurities in semiconductor products were reviewed. The overall conclusion of this study was that the ALD coatings provide a worthy solution for metal contamination control. Some differences between the passivation efficiencies of different metal – coating systems were found.

The focus of this thesis is on the recent changes in ethnic and class relations that have taken place in Bolivia since the beginning of the 21st century with the expansion of the economic middle class and the rise of the indigenous movements, Evo Morales and his socialist party to political power. This is approached through the medium of coca leaf, a key symbol of the Central Andean indigenous peoples, and its chewing that has recently been appropriated by all social layers of Bolivia. The recent popularity of coca challenges the race-based class structure of Bolivia, where prejudices on indigenous peoples have been epitomised in coca. The realities of social change are investigated by looking into the contemporary perceptions that Bolivians have towards coca, and how its increasing use reflects the changing identities and relations between different social layers. The city of Tarija was chosen as the primary field site as coca is commonly chewed there publicly. As previous anthropological research on coca has mainly been conducted in rural surroundings, this thesis illuminates how the leaf is used by the urban population of Bolivia. The principle research questions are: How is the chewing of coca leaf perceived and practiced by the different layers, of the contemporary society of Tarija, and how does this contribute to the production of separate ethnic and class identities, but also national and departmental unity? This thesis is mostly based on ethnographic fieldwork conducted in Bolivia between 3 December 2018 and 23 February 2019, of which two months were spent in the city of Tarija and it surroundings, while one month of supplementary research was conducted in other parts of Bolivia. In addition to participant observation, the material collected included 14 recorded interviews as well as 63 informal interviews. Besides ethnographic data, this thesis also analyses the history of coca leaf at the epicentre of racial and social relations of Bolivian society, which also includes its place as one of the main ingredients of the global drug trade. As the perceptions surrounding coca are linked to its possible narcotic qualities and medical applicability, an analysis of the medicinal value of the coca leaf is included to provide a background for the claims made by the interviewees. To approach the multiple meanings of the coca leaf, this thesis employs a locally engaged theory. Anthropological concepts and theories of multiple origins are employed and applied throughout the ethnographical analysis to build a multi-sited and encompassing understanding of coca chewing. The identities are approached from an intersectional perspective to show the complexity of identity building, where gender, age, race and class are in interaction with each other. The reasons that members of different groups give for coca chewing and how these reasons work to create differences between the chewers are analysed to demonstrate how the traditional upper and middle classes of Tarija do not partake in the key symbolism that coca has for the Central Andean indigenous peoples. Instead, they perceive coca as an ancient medicine, a national emblem that works to create unity between all Bolivians by connecting them to their shared indigenous roots, while the chewing of the leaf for work-related reasons, as a stimulant, is perceived to be practiced mainly by the rural population and the working class. By further differentiating the zones of coca production to traditional producers and narcotraffickers, and as also demonstrated with an analysis on the public chewing of coca, this thesis argues that through coca chewing, the traditional upper and middle classes are able to overpass the racism previously employed in demonstrations against Evo Morales and his socialist party. Their new rhetoric highlights national unity regardless of class or ethnicity in the name of democracy. The ambiguous relation that the people of Tarija have towards coca reflects the ambiguous relations that exist between the different social layers of the city. The increasing popularity of coca reflects the social change that has diluted the colonial race-based boundaries between social classes, but also the limits of this change, as many of the prejudices and stereotypes previously attached to race and coca, instead of disappearing, have been reassigned to low income levels and political affiliation.

This study examines the use of migrants or asylum seekers as a means of pressure by States towards other States. The term ‘coercive engineered migration’ (CEM) by Kelly Greenhill, denoting cross-border population movements that are deliberately created or manipulated in order to induce political, military and/or economic concessions from a target State or States, is used as the factual framework in this study to describe the phenomenon under examination. Inspired by the recent events between Belarus and its neighbours, this study looks at a situation, where a sending State, outside the EU and CoE, is deliberately sending asylum seekers to its neighbour, the receiving State, being an EU and CoE Member State. The research question guiding this study is: ‘Can an EU and CoE member State receiving asylum seekers in connection to a situation of coercive engineered migration prevent the entry into its territory from said individuals?’ An answer is attempted via doctrinal analysis of the receiving State’s rights under the jus ad bellum and parallel obligations under international human rights law, namely obligations relating to non-refoulement and collective expulsion of aliens under the ECHR. It is submitted that a CEM situation may amount up to a use of force and where it does, in order to draw a balance between the State’s rights and the human rights of the asylum seekers, the receiving State should be able to derogate from its collective expulsion-related obligations under the ECHR and the EU Fundamental Rights Charter in order to close off a portion of its land border to defend itself against the CEM situation deliberately created by the sending State.

This master thesis discusses two main tasks of computational etymology. First, finding cognates in multilingual text. Second, finding underlying correspondence rules by aligning cognates. For the first part, I briefly described two categories of methods in identifying cognates: symbol based and phonetic based. For the second part, I described the Etymon project, which I had been working in. The Etymon project uses a probabilistic method and Minimum Description Length principle to align cognate sets. The objective of this project is to build a model which can automatically find as much information in the cognates as possible without linguistic knowledge as well as find genetic relationship between those languages. I also discussed the experiment that I did to explore the uncertainty in the data source.

Recent evidence suggests paranormal and religious beliefs may result from cognitive biases that all humans share. People who think in an intuitive manner are supposedly more affected by these biases than analytical people. Consequently, mounting evidence suggests those who endorse intuitive thinking style tend to be more religious and have more paranormal beliefs than people with an analytic thinking style. However, less attention has been paid to people who are highly analytical but nevertheless have supernatural beliefs. Since analytical people should be less susceptible to cognitive biases, other factors such as metacognitive tendencies might account for these beliefs. On the other hand, if intuitive thinking style is a major causal factor behind paranormal beliefs, an intuitive sub-group among sceptics could be considered an anomaly. Metacognitive tendencies could be a potential psychological factor behind scepticism. A sample of nearly 3000 Finnish participants revealed that there was an analytical and intuitive subgroup among the believers and sceptics. Particularly, analytic believers had more cognitive biases and lesser tendency to belief flexibility than analytic sceptics. Intuitive sceptics had more cognitive biases than analytic sceptics but they adhered more to flexible thinking than intuitive believers. The results of this thesis underline the multifarious nature of both paranormal beliefs and thinking styles. Although analytical thinking may help the person to overcome the automatic and often erroneous shortcuts that the mind produces, it may fail to suppress overlearned and reflectively practiced beliefs. On the other hand, an intuitive thinking style and cognitive biases may not necessary lead to paranormal believing, especially if the living environment encourages a sceptic worldview. Future studies should address the mechanisms that lead individuals with similar epistemological tendencies to acquire totally different metaphysical beliefs.

Background and purpose: Cognitive impairment is a common and well-known consequence of supratentorial infarct, but its prevalence and severity after infratentorial infarct is unclear. We compared the frequency and prognostic value of domain-specific cognitive deficits after supratentorial and infratentorial infarct. Methods: In a consecutive cohort of first-ever stroke patients (N=244) admitted to Helsinki University Hospital, 37 patients had an infratentorial infarct. Patients were assessed by a neuropsychologist 3 months post-stroke in 9 cognitive domains, and functional disability was assessed at 15 months. Frequencies of cognitive deficits were compared using the Pearson chi-square test. The association between cognitive deficits and functional disability at the 15-month follow-up was analysed using logistic regression. Results: There was no significant difference between the frequency of cognitive deficits in patients with infratentorial vs supratentorial infarct. Altogether 73% of patients with infratentorial infarct and 82.1% of patients with supratentorial infarct had impairment in at least one cognitive domain, and 42.3% in the infratentorial group and 47.3% in the supratentorial group had deficits in 3 or more cognitive domains. In the infratentorial group, only visuoconstructional and spatial functions showed at least a convincing trend of association with functional disability at 15 months (OR 9.0, 95%CI 1.3-62.5, p=0.027). In the supratentorial group, both executive functions and attention (OR 2,9, 95%CI 1.5-5.8, p=0.002) and visuoconstructional and spatial functions (OR 2.9, 95%CI 1.5-5.7, p=0.001) showed this association. Conclusion: Cognitive deficits are as common in infratentorial as in supratentorial infarct, and it is important to recognize them to meet the needs of rehabilitation.

Objective: Both stress-related exhaustion and depression have previously been associated with a decline in cognitive performance, but there is a lack of evidence on whether these conditions have different associations with different cognitive domains and whether they have additive effects on cognitive performance. Furthermore, very little is known about the cognitive effects of chronic stress-related exhaustion. Consequently, the aims of this study were to 1) examine the associations between current stress-related exhaustion and cognitive performance, 2) investigate whether different developmental trajectories of stress-related exhaustion are differently associated with cognitive performance, 3) compare the association between stress-related exhaustion and cognitive performance to the relationship between depressive symptoms and cognitive performance, 4) examine if individuals with comorbid stress-related exhaustion and depression have lower cognitive performance than individuals with at most one of these conditions (i.e., whether clinical stress-related exhaustion and clinical depression might have additive effects on cognitive performance). Methods: The data used in the study was a Finnish population-based sample of six cohorts born between 1962 and 1977 from the Cardiovascular Risk in Young Finns Study. Stress-related exhaustion was assessed using the Maastricht Questionnaire, depressive symptoms with the Beck Depression Inventory, and cognitive performance with four subtests of the Cambridge Neuropsychological Test Automated Battery, measuring visuospatial associative learning, reaction time, sustained attention, and executive functions. Cognitive performance and depressive symptoms were assessed in 2012, and stress-related exhaustion in 2001, 2007, and 2012. Participants were 35 to 50 years old in 2012. Linear associations between stress-related exhaustion and cognitive performance (N = 905) and depressive symptoms and cognitive performance (N = 904) were examined by conducting multivariate regression analyses. Age, sex, socioeconomic status, and parents’ socioeconomic status were controlled in the regression models. Additionally, multivariate analyses of variance were performed to investigate the different developmental trajectories of stress-related exhaustion and their relation to cognitive performance (N = 541) and the associations of comorbid stress-related exhaustion and depression with cognitive performance (N = 1273). Results and conclusion: The main finding was that high stress-related exhaustion is associated with slower reaction times, but not with performance in spatial working memory, visuospatial associative learning, or executive functions. Ongoing, chronic stress-related exhaustion was more strongly associated with slower reaction times than short-term exhaustion experienced years ago. Compared to depressive symptoms, high stress-related exhaustion was associated with slower reaction times also when subclinical cases were included, whereas only clinical levels of depressive symptoms had an association with slower reaction times. There were no differences in cognitive performance between individuals with only stress-related exhaustion or depression and those with comorbid stress-related exhaustion and depression, which supports the notion that these conditions do not have additive effects on cognitive performance. These findings add to the existing evidence of the cognitive effects of stress-related exhaustion in the general population and have several practical implications. Further research is needed on the topic, preferably with longitudinal designs, more comprehensive cognitive measures, and clinical assessment of the psychiatric symptoms.

Microbial cellulases, e.g. cellobiohydrolases, are able to degrade cellulose and lignocellulosic biomass to smaller glucose-containing monomers and oligomers. Cellulases are often multi-domain enzymes comprised of different protein domains (i.e. modules), which have different functions. The main two components, which often appear in cellulases, are the cellulose-binding module (CBM) and the catalytic domain. The CBMs bind to cellulose, bringing the catalytic domains close to their substrate and increasing the amount of enzymes on the substrate surface. The catalytic domain performs the cleavage of the substrate, e.g. in the case of cellobiohydrolases hydrolyses or “cuts” the crystalline cellulose chain into smaller soluble saccharides, mainly cellobiose. Unlike aerobic fungi, which utilize free extracellular enzymes to break down cellulose, anaerobic microbes often use a different kind of strategy. Their cellulases are organized and bound to the cell surface in a macromolecular protein complex, the cellulosome. The core of the cellulosome is formed of a scaffolding protein (the scaffoldin) consisting mainly of multiple consecutive cohesin domains, into which the catalytic subunits of enzymes attach via a dockerin domain. This creates a protein complex with multiple different catalytic domains and activities arranged in close proximity to each other. Dockerins and cohesins are known to bind each other with one of the strongest receptor-ligand -pair forces known to nature. Dockerin containing fusion proteins have also been successfully combined in vitro with proteins containing their natural counterparts, cohesins, to create functional multiprotein complexes. In this Master’s thesis work the goal was to 1) produce fusion proteins in which different CBMs were connected to dockerin domains, 2) combine these fusions with cohesin-catalytic domain fusion proteins to create stable CBM and catalytic domain containing enzyme complexes, 3) to characterize these enzyme complexes in respect of their thermostability and cellulose hydrolysis capacity and 4) to ultimately create a robust and fast domain shuffling method for multi-domain cellobiohydrolases (CBH) to facilitate their faster screening. The hypothesis of the experiments was that different CBMs fused with a dockerin domain and the cellobiohydrolase catalytic domain fused with a cohesin domain could be produced separately and then be combined to produce a functional two-domain enzyme with a dockerin-cohesin “linker” in between. In this way time and work could be saved because not every different CBM- catalytic domain -pair would have to be cloned and produced separately. Several CBM-dockerin fusion proteins (in which the CBM were of fungal or bacterial origin) were tested for expression in heterologous hosts, either in Saccharomyces cerevisiae or Escherichia coli. The purified proteins were combined with a fungal glycoside hydrolase family 7 (GH7) cellobiohydrolase-cohesin fusion protein produced in S. cerevisiae. The characterization of the catalytic domain-CBM -complexes formed through cohesin-dockerin interaction included thermostability measurements using circular dichroism and activity assays using soluble and insoluble cellulosic substrate. The results were compared to enzyme controls comprising of the same CBM and catalytic domain connected by a simple peptide linker. The results showed that the cohesin-dockerin –linked cellobiohydrolase complex performed in the cellulose hydrolysis studies in a similar manner as the directly linked enzyme controls at temperature of 50˚C and 60 ˚C. At temperatures of 70 ˚C the complex did not perform as well as the control enzymes, apparently due to the instability of the dockerin-cohesin interaction. The thermostability measurements of the enzymes, together with the previously published data supported the hydrolysis results and this hypothesis. The future work should be aimed at enhancing the thermostability of the cohesin-dockerin interaction as well as on verifying the results on different cellulase fusion complexes.

Johdanto Ennen teho-osastolle saapumista aloitettu viilennyshoito kylmillä suonensisäisillä nesteillä ei vaikuta parantavan sairaalan ulkopuolella sydänpysähdyksen saaneiden potilaiden funktionaalista ennustetta. Hypoteesinamme oli, että tämä johtuu tehottomasta viilennyksestä ja hoidon sivuvaikutuksista. Aineisto ja menetelmät Post hoc-analyysi alijoukosta potilaita (n = 352), jotka olivat mukana TTH48-tutkimuksessa (NCT01689077) ja joko saivat kylmiä suonensisäisiä nesteitä ennen teholle saapumista, tai eivät saaneet. Tietoja kerättiin potilaiden lähtötilanteesta, sydänpysähdykseen liittyvistä tekijöistä, viilennysmenetelmistä, sivuvaikutuksista ja kehon lämpötilasta eri hoidon vaiheissa. Ensisijainen päätepiste oli kesto spontaanin verenkierron palautumisesta tavoitelämpötilaan (<34°C) ja toissiajiset päätepisteet olivat verenkiertoon liittyvät sivuvaikutukset, elektrolyyttihäiriöt ja hypoksia ensimmäisten 24 tunnin aikana tehohoidossa. Vähintään yhden tunnin ero ajassa tavoitelämpötilaan määriteltiin ennalta merkittäväksi. Tulokset Tutkimukseen mukaan otetuista 352 potilaasta 110 saivat kylmiä suonensisäisiä nesteitä ennen teho-osastolle saapumista. Mediaani aika spontaanin verenkierron palautumisen ja tavoitelämpötilan saavuttamisen välillä oli pidempi ryhmässä, joka sai kylmiä nesteitä verrattuna ryhmään, joka ei saanut (318 vs. 281 min, p < 0.01). Kylmien nesteiden käyttö ennen tehoosastolle saapumista ei assosioitunut tavoitelämpötilan saavuttamisen kestoon lineaariregressiomallissa sisältäen hoitokeskuksen, painoindeksin, sydämen vajaatoiminnan, diabeteksen ja sydänpysähdyksen keston (standardoitu beta vaikutuskerroin: 0.06, 95% luottamusvälit B:lle -49 ja 16, p = 0.32). Ryhmien välillä ei ollut eroa hypoksian yleisyydessä tehoosastolle saapuessa (1.8% ja 3.3%, p = 0.43) tai elektrolyyttitasapainon häiriöissä (hyponatremia: 1.8% ja 2.9% p = 0.54; hypokalaemia: 1.8% ja 4.5%, p = 0.20). Sairaalakuolleisuudessa ei ollut eroa ryhmien välillä. Johtopäätökset Tavoitteellisen lämpötilan hallinnan aloittaminen kylmillä suonensisäisillä nesteillä ennen tehoosastolle saapumista ei lyhentänyt kestoa spontaanin verenkierron palautumisesta tavoitelämpötilaan pääsemiseen. Emme löytäneet tilastollisesti merkitsevää eroa kuolleisuudessa tai sivuvaikutusten yleisyydessä ennen teho-osastolle saapumista kylmien nesteiden antamisen perustella jaotelluissa ryhmissä.

Tämä tutkielma tarkastelee aistiverbien koleksifikaatiotyyppejä Itämeren kielialueen kielissä, eli miten tämän kielialueen kielet erottelevat aistiverbien perusmerkityksiä leksikaalisesti, ja toisaalta mitä perusmerkityksiä kielet ilmaisevat samalla lekseemillä, eli koleksifikoivat. Tutkielma edustaa sekä leksikaalista typologiaa että areaalista kielitiedettä. Aikaisemmassa tutkimuksessa on havaittu areaalisia koleksifikaatiotyyppejä, niin aistiverbien kuin muidenkin semanttisten kenttien kohdalla. Itämeren kielialueen kielet ovat olleet kontaktissa tuhansia vuosia ja niistä löytyy monia areaalisia piirteitä, ulottuen fonologiasta leksikkoon. On myös esitetty, että alueen uralilaiset kielet ovat indoeurooppalaistuneet kontaktin myötä, ja toisaalta alueen indoeurooppalaisista kielistä on löydetty uralilaisia piirteitä. Tämän tutkielman tarkoituksena on tarkastella, onko Itämeren kielialueen kielissä havaittavissa jaettuja aistiverbien koleksifikaatiotyyppejä, ja onko koleksifikaatioissa havaittavissa ns. indoeurooppalaistumista tai uralilaistumista. Tutkielmassa verrataan Itämeren kielialueen kieliä sekä keskenään että verrattuna sukukieliin, joita puhutaan alueen ulkopuolella. Tutkielman aineisto kerättiin kyselylomakkeella, jossa äidinkielisiä puhujia pyydettiin kääntämään omalle äidinkielelleen englanninkielisiä lyhyitä lauseita, joissa esiintyi aistiverbejä. Lopullinen aineisto sisältää 199 vastausta 40 kielellä, joista kahdeksan on uralilaisia kieliä ja 32 Euroopassa puhuttavia indoeurooppalaisia kieliä. Itämeren kielialueen kielistä tutkimuksessa on edustettuna 14 kieltä, jotka kuuluvat viiteen eri kielihaaraan. Itämeren kielialueen ulkopuoliset kielet aineistossa muodostavat kontrolliryhmän, jota vasten kielikontaktien mahdollisia vaikutuksia voidaan verrata. Analyysissä jokaisesta kielestä tunnistettiin mahdolliset koleksifikaatiot, ja kieltenvälinen vertailu tapahtui sekä kielihaaran että -kunnan tasolla. Itämeren kielialueen kieliä verrattiin sekä suhteessa toisiinsa että suhteessa alueen ulkopuolella puhuttuihin sukukieliin. Tutkimuksesta selviää, että Itämeren kielialueen kielet eivät jaa yhtä yhteistä aistiverbien koleksifikaatiotyyppiä, vaan kielistä löytyy useita erilaisia tyyppejä. Tulokset osoittavat myös, että koleksifikaatiotyypit ovat hyvin samanlaisia samaan kielihaaraan kuuluvien lähisukukielten kesken. Osa Itämeren kielialueen kielistä kuitenkin poikkeaa huomattavasti lähisukukielistään, ja koleksifikaatiotyypeistä löytyy yhtäläisyyksiä myös kielisukulaisuusrajojen yli. Sama koleksifikaatiotyyppi löytyy mm. ruotsista, virosta ja meänkielestä, jotka samalla poikkeavat lähisukukielistään. Myöskin latvia ja liettua poikkeavat toisistaan, ja liettuan koleksifikaatiotyyppi muistuttaa slaavilaisista kielistä löytyvää mallia. Osa tuloksista näyttää heijastelevan kielikontaktien vaikutusta. Tutkimuksesta selviää myös, että osa koleksifikaatiotyypeistä on hyvin yleisiä kielikunnasta ja -haarasta riippumatta, joten kielikontakti ei välttämättä ole ainoa yhtäläisyyksiä ja eroavaisuuksia selittävä tekijä.