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Geologic knowledge is often inferred from heterogeneous and sparse datasets. Thus, integrating disparate data is one of the essential phases in geologic research. Integrating geologic and geophysical observations and models is typically performed using proprietary modeling software. The methods for integrating data often utilise concepts based on the relational model for data. The relational model provides the theoretical basis for designing data management systems where the consistency of data is ensured. In this study, the relational model was used for geologic and geophysical data by designing a data model for integrating reflection seismic data from the Finnish Reflection Experiment together with chosen geophysical and geologic data. The data model was implemented in a relational database management system and the data is handled in a manner that ensures the internal and referential consistency of the data. A web GIS application was designed and implemented to visualise the Finnish Reflection Experiment data together with other relevant datasets. The application utilises a service-oriented architecture, where external services providing data or features are utilised to enhance the capabilities of the application. The external services are accessed using widely standardised web technologies and thus it is easy to extend or alter the datasets used in the application. The web GIS application makes it possible to visualise Finnish Reflection Experiment data together with other data using any device with a web browser. The web GIS application has been published as a part of the OpenFIRE service, running in the AVAA portal of the Open Science and Research Initiative. In the OpenFIRE service, additional download service has been designed for the application in collaboration with the AVAA team of the Open Science and Resarch Initiative. In the service, the web GIS application can be used to browse Finnish Reflection Experiment data in a proper context together with other datasets. By modeling data it was possible to improve the quality of the national geologic data repository from which data was used in the web GIS application. The data management processes of the national data repository are recommended to be reviewed using the data management theory methods discussed in this study. Considering that there are currently various ongoing data and research infrastructure programmes without many prototypes in production, the methods discussed and utilised in this study could be considered as examples of design and implementation of a domain-specific data visualisation service and data management practices, especially in the fields of bedrock geology and solid Earth geophysics.

Aim of this study is to develop biogeochemical exploration methods for cobalt. Several different samples were collected from study area, analyzed, and compared to each other. This study took place at Rautio village at North Ostrobothnia and more accurately over the Jouhineva mineralization. Jouhineva is well-known high-grade cobalt-copper-gold mineralization. Elements examined in this study are cobalt, copper, arsenic, zinc, selenium, and cadmium. Samples were collected from three different study profiles from the area. From these three profiles samples collected are: soil, pine, lingonberry, birch, rowan, and juniper. Water samples were collected around the study area from every location possible. Soil samples were analyzed with four different methods: Ionic leaching, aqua regia, weak leaching and pXRF. Ionic leaching and aqua regia had both elevated concentrations of cobalt, but in different locations depending on study profile. Ionic leaching detects rising ions from the ore and therefore elevated concentrations are found at different locations compared to aqua regia. Aqua regia results proved how different orientation of study profile, direction of the ore and glacial flow can affect to the anomalies of elemental concentration. Profile-2 was oriented differently to ore and glacial flow than Profile-1, and therefore elevated concentrations of cobalt and copper were not drifted away from the ore on Profile-2 like they were on Profile-1. Aqua regia and pXRF have very similar copper, arsenic and zinc results. Pine and lingonberry turn out to be the most promising plant species applied for cobalt exploration, and rowan appears to be most suitable for copper exploration. Lower detection limit could significantly improve pine analyses as exploration method and more extensive sampling could remove some of the uncertainties about the method. Lingonberry samples have elevated concentration of copper and arsenic. Birch and juniper produced somewhat unclear results. Despite this, cobalt and copper concentrations in birch leaves were elevated when compared to concentrations found in other studies. In addition to this birch is suitable for arsenic exploration. Juniper had elevated copper concentration in the study area compared to other studies. Water samples collected from the Jouhineva area yielded concentrations of cobalt, copper and arsenic that were above the average concentration in the Kalajoki area waters. Copper and arsenic were above the average concentration of the Kalajoki area in every sample collected from the study area. Cobalt was above the average concentration in all samples that were not collected directly from the pond formed in the old test mine. Zinc concentration was below the average limit in all samples collected from the area. Zinc concentration in the water samples collected from the pond is significantly lower compared to the other samples collected from the area.

Paralytic shellfish poisoning toxins belong to a group of marine biotoxins that can cause severe food poisoning. The marine biotoxins have highly varying properties, such as molecular weight, solubility and toxicity. They accumulate into shellfish during harmful algal blooms. The global fish industry monitors sea food prior to releasing them to the market to ensure the safety of consumers, and permitted levels of marine biotoxins are regulated worldwide. Possible bioterrorism use of marine biotoxins is a concern to the governments due to their high toxicity and availability. The main emphasis in this thesis is on paralytic shellfish poisoning toxins, saxitoxin and its analogues. Saxitoxin is listed under the Chemical Weapons Convention. The paralytic shellfish poisoning toxin analogues share physico-chemical properties such as solubility, but they differ highly from each other in toxicity. The most toxic analogues of paralytic shellfish poisoning toxins are the Saxitoxin and Neosaxitoxin. The toxicity of the paralytic shellfish poisoning toxins is due to the blocking of the voltage gated sodium channels, which is a reversible process. The symptoms of paralytic shellfish poisoning can be numbness, weakness and even paralysis, which can lead to respiratory failure. The paralytic shellfish poisoning can be lethal and there is no antidote. A new liquid chromatography- tandem mass spectrometric method using multiple reaction monitoring was developed. Several different hydrophilic interaction liquid chromatography type analysis columns were compared. A liquid chromatography- high resolution mass spectrometric analysis methods using full scan and product ion scan were developed for several of the paralytic shellfish poisoning toxin analogues. The limit of detection and limit of quantification for Saxitoxin analyzed with the high resolution mass spectrometry method were 0.2 ng/ml and 0.7 ng/ml respectively. In average the detection and quantification limits obtained with the high resolution mass spectrometry were around ten times better than the values obtained using triple quadrupole mass spectrometry. New sample preparation methods were developed for four different matrices (mussel, urine, milk and juice) applying solid phase extraction as the primary sample clean-up technique to be used in proficiency tests. Proficiency test samples analyzed during this thesis contained mussel, urine and unknown saxitoxin samples. The proficiency test samples were analyzed using three different chromatography-based analysis techniques to determine the presence of paralytic shellfish poisoning toxins. A comparison was done between the developed triple quadrupole mass spectrometric method, high resolution mass spectrometric method and a standardized fluorescence detection method.

This project has aimed to investigate and propose improvements to the methods used in the System for Integrated ModeLing of Atmospheric coMposition (SILAM) model for simulating biogenic volatile organic compound (BVOC) emissions. The goal is to study an option in SILAM to use the Model for Emission of Gases and Aerosols in Nature, Version 3 (MEGAN3) as an alternative to SILAM’s existing BVOC calculation algorithm, which is a more simplified approach. SILAM is an atmospheric chemical transport, dispersion, and deposition modelling system owned and continuously developed by the Finnish Meteorological Institute (FMI). The model’s most well-known use is in forecasting air quality in Europe and southeast Asia. Although traffic and other urban emissions are important when modelling air quality, accurate modelling of biogenic emissions is also very important when developing a comprehensive, high-quality regional and sub-regional scale model. One of the motivations of this project is that if BVOC emission simulation in SILAM were improved, the improvements would be passed into subsequent atmospheric chemistry algorithms which form the molecules responsible to produce secondary organic aerosols (SOA). SOA have significant impacts on local and regional weather, climate, and air quality. The development in this project will therefore offer the potential for future improvement of air quality forecasting in the SILAM model. Because SILAM requires meteorological forecast as input boundary conditions, this study used output generated by the Environment-High Resolution Limited Area Model (Enviro-HIRLAM), developed by the HIRLAM Consortium in collaboration with universities in Denmark, Finland, the Baltic States, Ukraine, Russia, Turkey, Kazakhstan, and Spain. Enviro-HIRLAM includes multiple aerosol modes, which account for the effects of aerosols in the meteorological forecast. Running SILAM with and without the aerosol effects included in the Enviro-HIRLAM meteorological output showed that aerosols likely caused a minor decrease in BVOC emission rate. This project has focused on the boreal forest of Hyytiälä, southern Finland, the site of the Station for Measuring Ecosystem-Atmosphere Relations - II (SMEAR-II, 61.847°N, 24.294°E) during a one day trial on July 14, 2010. After performing a test run over the Hyytiälä region in July 2010 for analysis, it was found that SILAM significantly underestimates BVOC emission rates of both isoprene and monoterpene, likely because of an oversimplified approach used in the model. The current approach in SILAM, called ‘Guenther Modified’, uses only a few equations from MEGAN and can be classified as a strongly simplified MEGAN version, with selected assumptions. It references a land cover classification map and lookup table, taking into account only three parameters (air temperature, month, and solar radiation) when performing the calculations. It does not take into account several other important parameters, which affect the BVOC emission rates. Based on qualitative analysis, this appears to be a simplified but limited approach. Therefore, based on these findings, the next step to improve SILAM simulations is to propose a full implementation of MEGAN as a replacement to the current logic in SILAM, which is to use land classification and a lookup table for BVOC emission estimates. MEGAN, which is a much more comprehensive model for simulating BVOC emissions from terrestrial ecosystems. MEGAN includes additional input parameters, such as Leaf Area Index (LAI), relative humidity, CO2 concentration, land cover, soil moisture, soil type, and canopy height. Furthermore, this study found that in the future, simulations involving BVOCs could also potentially be improved in SILAM by adding modern schemes for chemical reactions and SOA formation in future development of SILAM. After gaining in-depth understanding of the strengths and limitations of BVOC in the SILAM model, as practical result, some recommendations for improvements to the model are proposed.

Introduction: EU medical device regulation (MDR) sets requirements for medical device software (MDSW) development. Following international standards, such as IEC 62304 and IEC 82304-1, is considered best practice to ensure compliance with regulation. At first glance, MDR and standards seem counter-intuitive to the DevOps approach. DevOps has been successful in regular software development, and it could improve MDSW development. In addition, standalone software is more prevalent as a medical device and as software does not need to be embedded into a physical device, the DevOps approach should be more feasible. Methods: In this thesis, a systematic approach of multivocal literature review was conducted. The goal is to find the state-of-the-art of DevOps in MDSW development, what DevOps techniques and practices are suggested by academic literature and industry experiences, and what the challenges and benefits of DevOps are in MDSW. 18 scientific articles and 10 sources of gray literature were analyzed. Results: The DevOps benefits of improved quality and faster release cycle can be achieved up to a certain point. Regulations prevent Continuous Deployment, but Continuous Integration (CI) and Continuous Delivery (CD) are possible. The most promising improvements can be made by automated documentation creation and bringing tasks of regulatory experts and developers closer together by streamlining the regulatory process. Existing DevOps tools can be extended to support compliance requirements. Third-party platforms and AI/ML solutions remain problematic due to regulations.

The temperature and the salinity fields (i.e. the hydrography) of the Baltic Sea determine the density and hence the stratification and density depended circulation of the sea. These features are affected by the changes in the hydrologic circulation, most importantly by the changes in the atmospheric circulation and in the water exchange with the North Sea. The aims of this thesis are to study the hydrographical conditions and changes for the period 1971 - 2007 of the surface and bottom layers of the Baltic Sea and the model sensitivity to number of variables. The surface layer is well studied, but on the whole Baltic Sea scale, the bottom layer studies are rare in number. The halocline and thermocline depths are also included, since they provide information about the mixing. By combining the information from the surface and the bottom, the overview for the whole hydrographical state is provided. For the analysis, three hindcast simulations based on the three-dimensional North-Baltic Sea model are used. The simulations differ in the number of vertical layers, initial conditions and the strength of the bottom drag coefficient. The results show that the vertical stratification is weaker in model than what is observed in in-situ measurements. The simulations differ remarkably in the salinity level and in its evolution. On average, the salinity is decreasing 0.1 - 0.4 ppt per decade except on the deepest parts of the Baltic Proper. The temperature is increasing at the surface and above the permanent halocline on average 0.2 - 0.4 degree Celsius per decade. Large regional differences between the west and east coast of the basins were found. The bottom temperature increase up to 1 degree Celsius per decade was found in the eastern coast of the eastern Gotland Basin, whereas on the Swedish coast the changes are more moderate and during some months, opposite. On the opposite site of the Bothnian Sea and the Gotland Basin, monthly anomalies up to degree Celsius were found for autumn months. In the deeper layers, the temperature decreases 0.2 - 0.4 degree Celsius per decade. The study showed that the Baltic Sea is undergoing a rapid change. In order to get a more detailed view of the changes in stratification and circulation, the changes in density should be studied next.

Radiation detectors are devices used to detect ionizing radiation. They can be manufactured from different materials for different purposes. Chemical vapour deposition (CVD) diamond detectors are semiconductor radiation detectors manufactured from artificial diamond grown using the CVD method. The physical properties of diamond make diamond detectors fast and radiation hard, and hence they are a favourable option for precise timing measurements in harsh radiation environments. The work presented in this thesis was done as part of a detector upgrade project of the TOTEM experiment at the Large Hadron Collider of CERN, the European Organization for Nuclear Research. The upgrade program includes the development and the building of a timing detector system based on CVD diamond in order to include the capability to perform precise timing measurements of forward protons. A new I-V measurement setup was built for the purpose of quality assurance measurements of diamond crystals before their further processing to timing detectors. When the setup was operated, different problems were observed, including electrical discharging, instabilities of leakage currents and unexpectedly high leakage current levels. The undesired effects disappeared, when the electrical contact used for supplying bias voltage to the measured samples was modified. Results of both quality assurance and measurements for the setup development are presented.

Subarctic ponds are important habitats for many freshwater species. The recent increase in global temperatures have stressed on the study of these habitats as rising water temperatures may have severe consequences to these cold and harsh ecosystems. Despite its importance, this topic has been largely overlooked in scientific research. Diatoms are microscopic, single-celled benthic algae, which are important indicators for environmental quality. Elevation is one of the main environmental variables controlling the composition and richness of diatom species as it shapes communities through several environmental variables such as temperature and water chemistry. The aim of this thesis was to illustrate the variability in diatom species richness and community composition along an elevational gradient in Kilpisjärvi and reveal the most important environmental drivers. As an additional focus, the applicability of the BenthoTorch sampling device was tested in measuring benthic algae biomass. Field and laboratory measurements were done using universal standards. Statistical analyses included multiple univariate and multivariate data analysis techniques. It was found that water pH, aluminium concentration and air temperature explained the variation in species richness and community composition the most. Elevation had only a secondary, non-significant role in shaping the diatom communities in subarctic ponds. Nearby sites showed similar compositions in terms of water chemistry and diatom communities. Biotope characterisation did not provide any further insight into the differences or similarities of diatom community composition or species richness. There were some differences in how genera responded to environmental variables. The centre of distributional range of many taxa was below the mid-point of the elevational gradient but species often occupied the whole elevational gradient. Rare taxa appeared at the ends of the elevational spectrum. The amount of singleton taxa was high (25.8%) and can be expected to increase with climate change. The BenthoTorch did provide reasonable results for benthic algae in the subarctic when compared to previous literature, but further research is required to grasp its full potential. More examination into the relationship between explanatory variables can be suggested (e.g. total phosphorus and ion balance) to gain better understanding on the changes in diatom species richness and community composition along elevational gradients.

Tämän tutkimuksen aiheena oli kehittää elektroniikkateollisuuteen liimoja, joilla on keskenään erilaiset elastiset moduulit. Tavoitteena oli muokata liimojen ominaisuuksia muuttamalla käytettyä siloksaanipohjaista polymeeriä. Ensimmäisessä vaiheessa difenyylisilaanidiolista (DPSD) syntetisoitiin dimeerejä ja trimeerejä; bis-DPSD:a ja tris-DPSD:a. Toisessa vaiheessa syntetisoitiin moolilmassaltaan pieniä kopolymeerejä, joiden synteesiin käytettiin kolmea edellämainittua DPSD:a tetrametoksisilaanin (TMOS) ja trimetoksi[2-(7-oksabisyklo[4.1.0]hept-3-yl)etyleeni]silaanin (ECHETMOS) reaktiossa. Ensimmäiseen kopolymeeriin käytettiin DPSD:a, toiseen dimeeristä bis-DPSD:a ja kolmanteen trimeeristä tris-DPSD:a. Kolmannessa vaiheessa kopolymeereistä valmistettiin liimaa lisäämällä kopolymeereihin täyteaineita, additiiveja ja katalyyttiä, jolla valmis liima saatiin kovetettua. Valmis liima saadaan ristisilloittumaan lämpökatalyytillä, kun ECHETMOS:n epoksiryhmät aukeavat ja reagoivat renkaanavautumispolymerisaatiossa. Tutkimuksen kirjallisessa osuudessa perehdyttiin siloksaani- ja silseskvioksaanipolymeerien reaktioihin, sovelluksiin ja niistä valmistettujen materiaalien ominaisuuksiin. Siloksaani- ja silseskvioksaanipolymeerejä käytetään elektroniikkateollisuudessa optisissa sovelluksissa. Ensin keskityttiin silaanien ja siloksaanien optisten ominaisuuksien tutkimukseen. Tämän jälkeen tutkittiin difenyylisilaanidiolin vaikutusta optisiin sovelluksiin käytetyissä siloksaanipolymeereissä. Dimeeristen ja trimeeristen difenyylisilaanidiolien oletettiin vaikuttavan valmiin liiman elastiseen moduuliin, koska ne ovat selvästi pidempiä ja jäykempiä yksiköitä verrattuna monomeeriseen DPSD:n. Työssä kuitenkin havaittiin, että DPSD:n kondensaatioreaktio trimeeriksi ei onnistunut toivotusti. Sen sijaan osoittautui, että tris-DPSD muodosti ainoastaan rengasmaisia rakenteita lineaaristen sijaan, jolloin tris-DPSD:ssa ei ollut jäljellä enää yhtään vapaita OH-ryhmiä, joiden avulla polymeeriä olisi voinut muodostua. Sen takia trimeerien vaikutusta polymeerin rakenteen jäykkyyteen ei päästy tutkimaan. Bis-DPSD säilyi lineaarisena, mutta tris-DPSD:a muodostui kaikissa reaktioissa, joista saatiin bis-DPSD:a. Käytännössä tämä aiheutti kovettumisongelmia liimoissa, koska liimoihin jäi tällöin aina myös monomeerista tris-DPSD:a, eli materiaalia ei saatu täysin ristisilloitettua. Monomeerista DPSD:a käyettäessä kopolymerointi TMOS:n ja ECHETMOS:n kanssa onnistui, ja tästä kopolymeeristä saatiin mekaanisesti kestävää liimaa.

Työssä esitellään ääretönharmonisten funktioiden ominaisuuksia. Ääretönharmoniset funktiot ovat äärettömän Laplacen yhtälön viskositeettiratkaisuja. Työn päämääränä on todistaa, että ääretönharmoniset funktiot ovat derivoituvia. Aluksi tutustutaan viskositeettiratkaisun määritelmään. Sen jälkeen esitellään vertailuperiaate kartiofunktioiden suhteen, ja osoitetaan, että ääretönharmoniset funktiot noudattavat kyseistä vertailuperiaatetta. Tällä ominaisuudella on useita hyödyllisiä seurauksia, jotka johdetaan kappaleessa 3. Erityisesti voidaan osoittaa, että funktiot, jotka noudattavat vertailuperiaatetta kartiofunktioiden suhteen ovat lokaalisti Lipschitz-jatkuvia. Kappaleessa 4 tutkitaan muokattua versiota äärettömästä Laplacen yhtälöstä. Muokatun version etuna on se, että ratkaisujen olemassaolo, yksikäsitteisyys ja säännöllisyys seuraavat standardista kvasilineaaristen osittaisdifferentiaaliyhtälöiden teoriasta. Kappaleessa 5 todistetaan, että ääretönharmoniset funktiot ovat derivoituvia. Sitä varten osoitetaan ensin, että ääretönharmoniselle funktiolle löydetään tangenttitaso jokaisessa määrittelyjoukon pisteessä. Tangenttitason olemassaolo seuraa pitkälti kappaleessa 3 johdetuista tuloksista. Lopuksi todistetaan, että ääretönharmonisen funktion tangenttitaso on yksikäsitteinen. Derivoituvuus seuraa suoraan tangenttitason yksikäsitteisyydestä. Kappaleen 4 tulokset muokatun version ratkaisusta ovat keskeisiä työkaluja todistettaessa tangenttitason yksikäsitteisyyttä.