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(2021)Parkinson´s disease (PD) is the second most common neurodegenerative disease in the world after Alzheimer´s disease. There is still no drug that alters the state of the disease. It has been found that Endoplasmic reticulum (ER) stress is one mechanism in PD. ER stress occurs due to accumulation of unfolded proteins. ER stress triggers Unfolded protein response (UPR) that protects against ER stress by decreasing unfolding of proteins. In the beginning, UPR has protective effect, but in prolonged ER stress UPR triggers apoptotic cell death. There are several key mediators in the UPR pathway. Characterisation of ER stress in PD models may be important for the current and future drug development of PD. If ER stress is a significant factor that affects the disease development, it would be important to find a drug that alters these mechanisms and UPR. This may be a way to halt the disease development. Different animal models of PD, like 6-OHDA (6-hydroxydopamine) and MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) model, have similarities in their mechanisms. It has been found that ER stress occurs both in the brain of PD patients and animal models of PD. That is why studying and further characterisation in animal models is relevant. The aim of this study was to characterize ER stress in 6-OHDA rat model. The expression of some key mediators of the UPR were determined in this study. There were male and female Spraque Dawley rats in this experiment. 6-OHDA or saline was injected intrastriatally in 3 spots by stereotaxic surgery. Two weeks after 6-OHDA lesions, amphetamine-induced rotation test was conducted to the rats. The rats were divided into groups based on lesion size according to the results. For this study, the rats were euthanised at week 2 or week 4 post lesion. The rats were euthanised by carbondioxide, and the death was confirmed by decapitation. The brains were collected and stored in -80°C. Striatum and substantia nigra were collected later. Total RNA was isolated from these samples. Part of the RNA sample was used to conduct cDNA synthesis. Finally, the gene expression of Atf4, Ire1α, Xbp1s, Xbp1t, Grp78 and Chop was measured from these cDNA samples by qPCR (quantitative polymerase chain reaction). The qPCR data describes the expression of exact gene. The data was processed prior to statistical analysis. By statistical analysis, it was possible to compare the expression of these genes between 6-OHDA group and vehicle group. In addition, comparison was made between 6-OHDA treated groups at week 2 and 4. According to the results, only Chop expression had increased in 6-OHDA lesioned rats at week 2 compared to the vehicle group. In other genes there were no statistical differences, unlike in several other studies where the expression was found to be increased. Thus, the characterisation of this model requires further studying, possibly by increasing the sample size and studying later time points as well.
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(2023)Gas chromatography (GC) is one of the most widely used method for analysis of lipids and it is commonly combined to a flame ionization detection (FID), since GC-FID is an excellent combination for quantitative analysis of wide range of lipids. Before GC analysis can be performed, lipids must be extracted from the sample and derivatized. Some common extraction methods include Soxhlet and Soxtec extraction, Folch extraction and extraction with the help of acid hydrolysis. To be able to analyse the extracted fatty acids by GC, they must be in a volatile form. This can be achieved by forming fatty acid derivatives by, for example, methylation. The commissioner wishes to have a way to analyse the fatty acid composition of pork by GC in their laboratory. The aim of the study was to take in use an easy, safe-to-use and simple method for determination of fatty acid composition of pork by gas chromatography, using the instruments and equipment already found from the laboratory. The research had three different parts. First, heptane-isopropanol extraction, Bligh & Dyer extraction and Caviezel extraction were compared. Then the chosen extraction method was validated. Finally, two different pork samples were compared to test the method’s ability to differentiate them. Caviezel extraction was chosen as the best extraction method, and it was validated by parameters repeatability and robustness. The method was able to differentiate samples that had similar, but slightly different fatty acid compositions. However, method still requires some fine tuning since the GC column seemed to be highly sensitive to any disturbances.
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(2020)Microbial volatile organic compounds are emitted by diverse set of microbial organisms and they are known to cause health hazards when present in indoor air. Early detection of fungal contaminated buildings and species present is crucial to prevent health problems caused by fungal secondary metabolites. This thesis focuses on analysing emission profiles of different insulation materials and fungal cultures, which allows, in further studies, to develop efficient new ways to detect fungi from contaminated buildings. Studied insulation materials consisted of cellulose and glass wool, which were analysed in multiple different conditions. Humidity of atmosphere was varied between 0-10 microliters and temperature was varied between 30°C and 40°C. In fungal emission profile study 24 different cultures were analysed in two different atmospheres, ambient and micro- aerophilic, and in multiple different inoculums. Analysis for both insulation materials and fungal cultures was done using headspace solid phase microextraction Arrow -tool and headspace in tube extraction –tool together with gas chromatography – mass spectrometry. One goal for this thesis was also test suitability of these methods for detection of fungal secondary metabolites. Comprehensive fungal emission profiles were successfully formed and new information from behaviour of insulation materials in different settings was found. In addition, new information about analysis methods and fungal behaviour in different atmospheres was found. Headspace solid phase microextraction Arrow with gas chromatography – mass spectrometry was found to be efficient, sensitive and timesaving method for indoor air study purposes. There were also many potential fungal culture specific biomarker compounds found for further study purposes.
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(University of HelsinkiHelsingin yliopistoHelsingfors universitet, 2011)Tämä lisensiaatin tutkielma koostuu kolmesta osasta; kirjallisuuskatsauksesta, kokeellisesta osasta ja liitteistä. Iohexol on ionisoitumaton, trijodattu ja vesiliukoinen röntgenvarjoaine. Iohexolia on hyödynnetty lääketieteessä useita vuosia. Iohexolia on käytetty muun muassa angio- ja myelografiassa, lisäksi iohexolia on hyödynnetty arvioitaessa munuaiskerästen suodattumisnopeutta sekä suoliston läpäisevyyden muutoksia. Hevosen tulehduksellisessa suolistosairaudessa (Inflammatory bowel disease, IBD) suoliston rakenne ja sen läpäisevyys muuttuu; tyypillistä on tulehdussolujen kertyminen suoliston seinämään ja myös sidekudosmuodostusta saattaa esiintyä. Suolisto muutoksia saatetaan havaita sekä ohut- että paksusuolessa. IBD aiheuttaa hevoselle laihtumista, johtuen ravintoaineiden puutteellisesta imeytymisestä ja proteiinien menetyksestä suoleen suoliston häiriötilan yhteydessä. Tällä hetkellä IBD:n diagnostiikka perustuu tyypillisiin oireisiin, kliiniseen tutkimukseen, verinäytteisiin, glukoosin imeytymistestiin ja peräsuolesta otettuun koepalaan. IBD:n diagnostiikka on kuitenkin erittäin haastavaa ja tutkimusmenetelmiin liittyy lukuisia ongelmia, jotka vähentävät niiden luotettavuutta IBD:n diagnostiikassa. Tutkimuksemme tarkoituksena on kehittää hevosen IBD:n diagnostiikkaa entistä helpompaan, luotettavampaan ja turvallisempaan suuntaan. Tämän alustavan tutkimuksen tavoitteet olivat: (1) tutkia voidaanko iohexol havaita hevosen seerumissa oraalisen annostelun jälkeen ja (2) muodostaa iohexolin pitoisuuskuvaaja ajan funktiona terveillä hevosilla. Materiaalimme koostui kymmenestä terveestä hevosesta, joilla ei ollut havaittu laihtumista tai ripulia. Ennen iohexolin annostelua hevosille suoritettiin kliininen tutkimus ja verinäytteet otettiin maha-suolikanavan sairauden poissulkemiseksi. Hevosille suoritettiin myös mahalaukun tähystys. 16 tunnin paaston jälkeen 1 ml/kg Iohexolia annosteltiin 10 % -liuoksena nenämahaletkulla suoraan mahaan ja verinäytteet otettiin 0, 30, 60, 120, 180, 240, 300 ja 360 minuuttia annostelun jälkeen. Iohexolin pitoisuus määritettiin käyttämällä korkean erotuskyvyn nestekromatografiaa. Iohexolin pitoisuuksista tietyillä ajanhetkillä muodostettiin kuvaaja. Hevosilla ei havaittu maha-suolikanavan sairauksia. Kaikki hevoset olivat hyvässä kuntoluokassa ja mahalaukun tähystyksessä ei havaittu merkittäviä muutoksia. Verinäytteiden tulokset olivat viiterajoissa. Kaikki hevoset sietivät iohexolia hyvin ja haittavaikutuksia ei havaittu. Iohexol oli havaittavissa seerumissa 60 minuutin kuluttua annostelusta. Kuvaajassa voitiin havaita kaksi huippua. Statistiset menetelmät tukivat löydöksiä. Iohexol testi oli yksinkertainen suorittaa ja siihen ei liittynyt haittavaikutuksia. Annos 1ml/kg oli havaittavissa seerumissa. Iohexolin pitoisuuskuvaaja muodosti kaksi huippua, ja tämänkaltainen ilmiö on kuvattu kirjallisuudessa aikaisemmin useiden lääkkeiden tapauksessa. Hevosella ilmiö liittyy todennäköisesti maha-suolikanavan rakenteellisiin ja fysiologisiin eroavaisuuksiin ja lisätutkimuksia ilmiön varmistamiseksi tarvitaan. Iohexol näyttää olevan potentiaalinen merkkiaine suoliston läpäisevyyden arviointiin ja lisätutkimuksia IBD:tä sairastavien hevosten seerumin iohexolin pitoisuuksista verrattuna terveiden hevosten seerumin iohexolin pitoisuuksiin on suunnitteilla.
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(2018)Short-chain aliphatic amines (SCAA) are present in multiple different matrices in the environment at low concentration levels. SCAA are considered to be environmentally relevant compounds due to their role as precursors in the formation of carcinogenic N-nitrosoamines in various matrices and new particle formation in the atmosphere. SCAA are characteristically highly volatile, polar, reactive and basic compounds. Consequently, the quantitative determination of SCAA tends to be rather challenging. In the literature part of this thesis, different analytical methods used for the determination of SCAA in environmental samples are reviewed. The typical approach for the analysis of SCAA has been the use of derivatization techniques. Derivatization converts SCAA into less polar and less volatile form, which enables the use of conventional separation techniques, such as gas chromatography (GC) and high-performance liquid chromatography (HPLC). However, the methods involving derivatization can be quite time consuming, require the usage of excess reagents and are mainly applicable for the analysis of primary and secondary SCAA. To reduce the amount of reagent and solvent consumption, microextraction techniques have been implemented as part of the derivatization methods. For the analysis of free SCAA, mainly ion chromatography (IC) and GC have been used. In recent years, also novel online mass spectrometry techniques have been used for the determination of free SCAA in atmospheric air. In the experimental part of this thesis, a novel solid-phase microextraction (SPME) device called SPME Arrow was used for the extraction of free SCAA. Different SPME Arrow sorbent materials were tested, including commercial and custom sorbents, extraction conditions were optimized and the performance of SPME Arrow was compared to conventional SPME fiber. The developed method was applied for the determination of SCAA in wastewater samples and atmospheric air samples. In general, the performance of the custom sorbent coated SPME Arrow was not adequate due to the deterioration of coating, although the preliminary results indicated possible selectivity towards dimethylamine. Considering the commercial sorbent coated SPME devices, the SPME Arrow was better than the SPME fiber in terms of limit of quantification and performance in real sample analysis. When the SPME Arrow was used for wastewater sample analysis, no matrix interferences were observed, opposite to the results obtained with the SPME fiber. In addition, the SPME Arrow could be used for the determination of SCAA in atmospheric air samples following prior preconcentration by using denuder for sampling.
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(2018)Sugar and Sugar alcohol are indicative compounds in the environmental aerosol which make them really important. The concentration of sugar and sugar alcohol reveal biogenic and anthropogenic information such as climate, air quality, wood consumption, the activity of plantation and pollution. The conventional analysis methods of sugar and sugar alcohol are reverse phase High Performance Liquid Chromatography–Mass Spectrometry (HPLC-MS/MS), and Gas Chromatography-Mass Spectrometry (GC-MS/MS). However, both of them have some limitations due to the sugar and sugar alcohol aerosol sample which are not easy to analyze. For reverse phase HPLC-MS/MS, the separation of analytes is not satisfied. For the GC-MS/MS, the derivatization process requires extra work and the derivatization compound is not stable. Besides, the matrix effect from the aerosol sample is a significant challenge which needs to be solved. Hence, the hydrophilic interaction chromatography (HILIC) and the Solid Phase Extraction (SPE) are introduced. The retention factors of HILIC column are the hydrophilic partition, the hydrogen bonding, and the electrostatic interactions. Polar stationary phase is used in HILIC mode, and the highly organic solvent is employed in mobile phase. Hence, a stagnant aqueous-rich layer is generated in HILIC mode, which can separate sugars and sugar alcohol efficiently. Furthermore, the interference and the matrix effect are solved by SPE. The development and the optimization of SPE-HILIC-MS/MS method for sugars were done in the experimental part. Eventually, the real environmental aerosol was analyzed by the optimized parameters and methods. The sugars and sugar alcohols were analyzed successfully from atmospheric aerosol samples.
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(2019)We humans utilise many kinds of chemicals, some of them are safe to use and some of them are dangerous to use. There are chemicals that fall into grey area in the terms of safety. Surfactants are one of them. They are used abundantly and they find their ways to the environment. It is an established fact that surfactants can more or less hinder normal functions of cells, and in the worst cases can cause cell deaths. Despite of this, it is not completely understood what harm surfactants can do to the living organisms in the environment. We live and work in houses that are cleaned with washing chemicals and surfactants. Recently, surfactants were supposed to exist in indoor air, and new studies prove this hypothesis. Literature explains that there might be the possibility that surfactants can adsorb into aerosols. However, analysis methods capable to be used directly for determination of surfactants in aerosol condensate samples are not available. In this M.Sc. thesis a new surfactant determination method was developed with capillary electrophoresis using UV detection and tetraborate complex formation. First surfactant determination methods, found from the literature for environmental samples were reviewed and described in this M.Sc. thesis. Then their suitability for experimental studies was evaluated. Among many options, capillary electrophoresis coupled with ultraviolet detection was selected. The method was developed for determination of didecyldimethylammonium chloride (DDAC) and polyethylene glycol monoalkyl ether (Genapol X-80), which are representatives of cationic and nonionic surfactans, respectively, and represent the surfactants in cleaning chemicals. In the experimental work method development was focused on composition of the electolyte solutions, since they played an important roles in separation and sensitivity of the analytes. First Tricine was selected for electrolyte, because it provided the best responses in the preliminary tests. However, in the later studies it, unfortunately, proved to be unsuitable for the determination of cationic and nonionic surfactants. Therefore, in accordance with published literature tetraborate electrolyte was chosen. As application studies, we demonstrated that the studied surfactants are present in water vapour by analysing seperately DDAC and Genapol X-80 in collected water condensates by laboratory scale piloting tests.The developed method was also applied to authentic samples of indoor water condensates and washing solutions that were collected from two elementary schools with air quality issues. Surfactants were detected in these samples too.
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(2022)In the past few years, there has been an increased consideration on the stem cell niche as a key factor to regulate stem cell maintenance and differentiation. Research on characterization of the stem cell microenvironment boosted after the determination of long-term three-dimensional (3D) tissue cultures, or so-called organoids. Organoids are derived from stem cells which self-organize in 3D multicellular structures upon embedding in an extracellular matrix mimic, such as Matrigel®. Their main advantage is these structures resemble the architectural distribution of the tissue of origin in vivo. Likewise, the cellular components of organoids vary depending on multiple variables as the tissue of origin and the growth factors they have access to. As a result of advances in this technique, some stem cell niches have been well characterized, as in the case of intestinal stem cells (ISCs), while others remain elusive as in case of the human gastric stem cells (hGSCs). Along with the remarkable development of 3D cultures, the interest of ECM proteins in stem cell regulation increased. Matrigel® is a rich matrix composed of several adhesive proteins such as laminins and collagens. Aside from providing structural support, the extracellular matrix (ECM) proteins forming this matrix contribute to cell adhesion and signalling. However, Matrigel® composition cannot be modified or even well-characterized due to its origin from Engelbreth-Holm-Swarm (EHS) mouse sarcoma cells. Additionally, it has been demonstrated that contains a high batch-to-batch variability. Other techniques to study the effects of individual ECM proteins have been used such as coating of tissue culture plates with ECM proteins. However, the biomechanical properties in this model are far from being physiological. Therefore, although preliminary results can be obtained using this technique, results extrapolation to an in vivo model can be questioned. To date, there is a lack of a reproducible, high-throughput and reliable technique to test the effect of ECM proteins on human gastric stem cells behavior. This Master’s thesis presents a novel transwell device containing a polyethylene glycol (PEG)-based hydrogel enriched with human ECM proteins to test their effect on human gastric stem cell regulation. Preliminary results showed that gastric organoid-derived epithelial cells (GODE) grown on hydrogels with ECM proteins that are localized at base of the gastric glands, such as Laminin-211, had a higher stem cell marker expression than the control grown on ECM proteins that are uniformly localized in vivo. Additionally, when GODE were grown on hydrogels containing ECM proteins that are localized at the surface of the native gastric epithelium, expression of surface gastric mucins markers was enhanced. These preliminary results highlight the utility of the optimized transwell device to further shed light on how the human gastric stem cells are regulated and what is the effect of the ECM proteins surrounding them.
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(2016)Magnetic field has a central role in many dynamical phenomena in the solar corona, and the accurate determination of the coronal magnetic field holds the key to solving a whole range of open research problems in solar physics. In particular, realistic estimates for the magnetic structure of Coronal Mass Ejections (CMEs) enable better understanding of the initiation mechanisms of these eruptions as well as more accurate forecasts of their space weather effects. Due to the lack of direct measurements of the coronal magnetic field the best way to study the field evolution is to use data-driven modelling, in which routinely available photospheric remote sensing measurements are used as a boundary condition. Magnetofrictional method (MFM) stands out from the variety of existing modelling approaches as a particularly promising method. The approach is computationally inexpensive but still has sufficient physical accuracy. The data-based input to the MFM is the photospheric electric field as the photospheric boundary condition. The determination of the photospheric electric field is a challenging inversion problem, in which the electric field is deduced from the available photospheric magnetic field and plasma velocity measurements. This thesis presents and discusses the state-of-the-art electric field inversion methods and the properties of the currently available photospheric measurements. The central outcome of the thesis project is the development and testing of a novel ELECTRICIT software toolkit that processes the photospheric magnetic field data and uses it to invert the photospheric electric field. The main motivation for the toolkit is the coronal modelling using MFM, but the processed magnetic field and electric field data products of the toolkit are usable also in other applications such as force-free extrapolations or high-resolution studies of photospheric evolution. This thesis presents the current state of the ELECTRICIT toolkit as well as the optimization and first tests of its functionality. The tests show that the toolkit can already in its current state produce photospheric electric field estimates to a reasonable accuracy, despite the fact that some of the state-of-the-art electric field inversion methods are yet to be implemented in the toolkit. Moreover, the optimal values of the free parameters in the currently implemented inversion methods are shown to be physically justifiable. The electric field inversions of the toolkit are also used to study other questions. It is shown that the large noise levels of the vector magnetograms in the quiet Sun cause the inverted electric field to be noise-dominated, and thus the magnetic field data from this region should not be considered in the inversion. Another aspect that is studied is the electric field inversion based only on line-of-sight (LOS) magnetograms, which is a considerable option due to much shorter cadence and better availability of the LOS data. The tests show that the inversions based on the LOS data have large errors when compared to the vector data based inversions. However, the results are shown to have reasonable consistency in the horizontal components of the electric field, when the region of interest is near the centre of the solar disk.
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(2014)The subject of this study is choice of law in international arbitration. The study focuses especially on the choice of substantive law, and the topic discussed is written from the perspective of the International Arbitration Rules of the U.S. arbitration institute ICDR. The ICDR (International Centre for Dispute Resolution) is the part of AAA (American Arbitration Association) which administers the international caseload. The study examines how the choice of applicable substantive law should be made in international arbitration according to the ICDR rules. The rules give the arbitrators a wide discretion in this sense, since they do not require the use of conflict rules to determine the substantive law. The study also discusses what exactly is meant by law and what kind of rules can be applied to solve the dispute. Questions related to the enforcement of an arbitral award is also brought up in the study, since it explores whether issues either with the choice of law or with the application of the substantive law can prevent the enforcement of the award. In addition to this, the arbitral institute ICDR is being presented in the study, since it is globally seen a significant provider of arbitration services. One of the objectives of the study is to demonstrate the specific characteristics of arbitration organized in the United States. The study is written in English.
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(2022)The literature review of this thesis presents the most utilized sample preparation and analysis methods for determination of trace elements from refinery feedstocks and end products during the last decade. The advantages and disadvantages of used methods and trends are presented. The challenges associated especially on silicon determination are discussed and possible solutions provided by publications are highlighted. The experimental part of this thesis is conducted in Neste’s Research and Development unit in Porvoo. The experimental part includes method development, study of siloxane compounds behavior and method validation for various sample matrices. The method development was performed by introduction of peristaltic pump to inductively coupled plasma- mass spectrometer (ICP-MS) sample introduction for two different methods (ASTM D8110M, NM 534) to replace previously used free aspiration method. The study of behavior of volatile siloxane compounds in different sample matrices including liquified waste plastics (LWP), and determination of these compounds was done with ICP-MS. The studied siloxanes showed great challenges due to their high volatility with the chosen methods. The method (ASTM D8110M, NM534) validation for different sample matrices were also done with ICP-MS. The validated matrices included several renewable matrices such as liquified waste plastics, fatty acids and other liquified waste samples and heavy fossil distillates. Repeatabilities of silicon concentration of sample as such and as spiked in intra- and inter-day, and spiked recoveries played an important role for method validation.
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(2023)Atmospheric aerosol particles play a significant role in urban air pollution, and understanding their size distribution is essential for assessing pollution sources and urban aerosol dynamics. In this study, we use a novel method developed by Kontkanen et al. (2020) to determine size-resolved particle number emissions in the particle size range of 3-800 nm at an urban background site and a street canyon site in Helsinki. Our results show overall higher particle number emissions in the street canyon compared to the urban background. On non-NPF event days, the particle number emissions of 3-6 nm particles in the urban background are highest in the noon. The emissions to the size range of 6-30 nm are highest during the morning or afternoon at both sites, indicating traffic is the main particle source in this size range. The emissions of larger particles are relatively low. Seasonal analysis suggests higher emissions during the summer in comparison to the winter which might be linked to higher product of mixing layer height (MLH) and particle number concentration in summer. Further investigations into particle emissions from different wind sectors suggest higher particle emissions from the urban sector than from the road sector in the urban background, contrary to the results for NOx concentrations. More research is needed to better understand the underlying factors. In addition, a comparison between particle number emissions estimated using FMI measurement MLH data and ERA5 model MLH data reveals that FMI data provides a more reliable representation of the MLH in the study area. Overall, the methods show limitations in accurately capturing particle dynamics in Helsinki. Future studies should address these limitations by employing more accurate NPF event classification and refining sector division methods.
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(2020)Rapid learning or fast mapping reflects the human brain’s ability to form new memory traces to novel words during exposure without the need for a long overnight consolidation period before the word can be used in conversation. This ability to acquire new words almost instantaneously may very well reflect how well-tuned the human language systems are to the phonemes of the native language. However, the neural basis of rapid learning has been largely unknown until recent neuroimaging studies. In this study on adult learners (n = 15), I recorded brain’s event-related potentials elicited by three different types of auditory bi-syllabic stimuli (native words, native pseudowords and pseudowords with unfamiliar phonemes, all acoustically closely matched) in a passive EEG-recording session before and after subjects participated in two types of training conditions. In the attend condition, subjects listened to a flow of stimuli while pressing a button when a target stimulus appeared. In the articulation condition subjects repeated out loud the heard stimuli. An auditory memory recognition test was administered after training to allow the comparison of neural learning effects to observable change in behaviour. Larger evoked responses were expected to correlate with better performance in the recognition task. All analyses were time-locked to the onset of the second syllable (critical disambiguation point/recognition point). A two-peak waveform was observed to all stimuli after both conditions, with the earlier peak appearing circa 40 ms and the later peak circa 140 ms after second syllable onset. Unlike in similar previous studies where responses increased as a result of learning, all responses decreased in magnitude. No statistically significant differences between the conditions were observed. This may have been due to either the small sample size, test subject fatigue or suppression effects due to repetition, masking any possible learning effects. For the late peak, native pseudowords evoked significantly stronger responses than native words or non-native pseudowords. Performance in the memory recognition task was good (above chance for all stimuli in both conditions), and as such learning cannot be excluded even though statistically significant differences in the evoked responses were not found. Further research and re-exploration of the data acquired here utilising source modelling might enable to assess in more detail the effect of attentive listening vs. articulation in rapid learning.
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(2022)MRS or magnetic resonance spectroscopy is an imagining technique which can be used to gain information about the metabolite concentration within a certain volume of interest. This can be used for example in brain imagining. The brain consists of three main types of tissue: cerebrospinal fluid, white and gray matter. It is important to know the different volume fractions of these tissues as the resolution in MRS is significantly lower than that of magnetic resonance imagining (MRI). The tissues all have different metabolite profiles and in order to get meaningful data the volume fractions need to be taken into account. This information can be gained from the segmentation of an image formed by using MRI. In this work a software tool was created to find these volume fractions with the input of a .rda file that is created by the scanner and Nifti file. The Nifti file is the image formed by using MRI and the .rda file is the manufacturers raw data format for spectroscopy data which has the relevant information about the volumes of interest. The software tool was created using Python and JavaScript programming languages and different functions of FSL. FSL is a comprehensive library of analysis tools used in brain imaging data processing. The steps for the software tool are: determining the coordinates of the volume of interest in FSL voxel coordinates, creating a mask in the correct orientation and location, removing non-brain tissue from the image using FSL’s tool tailored for that purpose (BET), segmenting the image using FSL’s segmenting tool (FAST), registering the mask on the segmented images and calculating the volume fractions. The software tool was tested on imaging data that was obtained at Meilahti Kolmiosairaala for the purpose of the testing. The testing data set included five different spectroscopy volumes from different parts of the brain and a T1 weighted image. The software tool was given the relevant information about the volume of interest in the form of a .rda file and the T1 weighted image in the form of a Nifti file. The software tool then determined the different volume fractions from all of the five volumes of interest. There is variation on the volume fraction of different brain areas within different brains and it is not possible to have an absolute reference value. The results of the test corresponded to the possible volume fractions that can be expected from the volumes in question.
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(2019)Linear elastic properties of ex vivo porcine lenses were characterized by compression and indentation tests. Compression tests were performed on un-glued lenses (N = 76), the average stiffness 12 ± 3 kPa (± sigma) and thickness 7.0 ± 0.3 mm were measured at 24 - 30 hours post mortem. For glued lenses (N = 70), the average stiffness was 15 ± 4 kPa and thickness 7.2 ± 0.4 mm. The shear modulus was 1.5 ± 0.3 kPa (N = 10) on average measured at 12 hours post mortem with indentation test. Compared to intact lenses, decapsulated lenses were 41% less stiff (N = 5) as measured with the compression test and the shear modulus was 65 % less (N = 10) as determined by indentation.
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(2021)Understanding the biomes and niches within forest ecosystems is key to maintaining and predicting micro-organism led processes, such as, nutrient recycling and disease proliferation. Insect-vectored fungi occupy the tree bark biosphere as incidental associates. Also, more selective transmission of fungi is seen via the beetle’s specialised structure called the mycangium. Mites carried by these insects, have also been described to vector fungi. Within these fungi are mycoviruses that express cryptic, beneficial, or detrimental effects to the host. The positive and negative effects on fungal host phenotypes encourage investigations into unknown virospheres. A study into the distribution of mycoviruses within bark-beetle vectored fungi in Finnish forests has yet to be carried out. The master’s thesis work continued an evaluation of viromes from 52 forest, bark-beetle vectored, fungal isolates transformed into 4 RNA libraries via high throughput sequencing platforming, using Illumina chemistry. Scots pine, Pinus sylvestris, and Norway spruce, Picea abies, logs were sampled. A further 31 fungal isolates were screened, via RT-PCR, for 22 putative viral sequences recovered from the RNA libraries. Patterns in viral sequence host range, co-infectivity and similarities between viral sequences were investigated. The viral sequences described in this study were unique to the databases searched against and could be looked at when maintaining the Finnish forest ecosystem. It was shown that positive-sense ssRNA viruses could play a major role in the virome of bark-beetle vectored fungi as 77.3 % of viral sequences described were classified as so. Mitovirus infections were most frequent across the two forests and, the interspecies-infective Ophiostomatoid mitovirus 2 strain was seen to infect at least four species, across two fungal genera. The description of Kuraishia capsulata narna-like virus 1 showing RNA dependent RNA polymerases (RdRp) across 2 genomes segments, supports current growing evidence, which in turn could contribute to the new classification of viruses within the Narnaviridae family.
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(2015)The aim of this study is to explore factors that affect novice teachers' well-being and thereby gain increased understanding for teachers' situation in Finland. The purpose of this study is to examine how novice teachers experience their first year of teaching and well-being, which factors affect novice teachers' well-being, how novice teachers perceive mentoring, what can lead to teacher resignation and how it can be prevented. In this qualitative study I have used phenomenographic analysis. In this analysis the focus is on description and understanding of experiences. The data was collected through semi-structured interviews and there were six respondents in total. The respondents were all novice teachers. Three of the respondents work as primary school teachers and the other three respondents have left the teaching profession. The interviews were arranged in September-November 2014. The findings show that the transition from student teacher to newly qualified teacher is a period filled with confusion, insecurity and excitement. Many of the respondents felt unprepared for the working life. All the respondents highlighted the importance of support during the first year of teaching. All the respondents felt mentally energetic and were emotionally invested in work, even though they all described the first year of teaching as an exhausting and tiring period of their lives. The findings also indicate that there are several factors that affect the well-being of a novice teacher. The respondents felt that it was challenging to find themselves, their working methods and routines. They also noticed having too high demands placed on themselves. The working environment is mentioned as one of the most important factors that influence teachers' well-being. The results also show that there are huge differences in how new teachers are being introduced to the school environment in Finland. All of the respondents felt that they were welcomed to their schools, but only three of the respondents received an own mentor. Respondents explained that they mostly needed help and guidance with different practical things. They also think that a supporting work climate is the most fundamental thing that promotes teachers' well-being. The findings of the study show that there are several factors that influence teacher resignation, for example a desire for greater challenges and more opportunities for career development. The teaching profession can be frantic, stressful and the workload can become overwhelming. Many respondents also think that teachers are underpaid and overworked. Respondents think that more effective mentoring methods could prevent teachers from leaving their profession. It is important to keep on developing new methods that support novice teachers during their first year of teaching.
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(2017)Tutkielma käsittelee suomenruotsissa esiintyviä suomenkielisiä substantiiveja sekä suomen ja suomenruotsin välistä koodinvaihtoa. Tutkielmassa pyritään etsimään mahdollisia säännönmukaisuuksia suomenruotsiin upotettujen suomenkielisten substantiivien suvussa ja taipumisessa. Tavoitteena on myös ottaa selvää, mitä suomenruotsiin upotettuja suomenkielisiä substantiiveja käytetään kirjallisessa ja/tai suullisessa ilmaisussa. Lisäksi tutkielmassa keskustellaan koodinvaihdosta ja lainasanoista kielitieteellisinä ilmiöinä. Tutkielman aineistona käytetään Korp-tietokantaa, joka sisältää 56 korpusta kirjoitettua suomenruotsia. Lukumäärä koostuu verkkoteksteistä (2), viranomaisteksteistä (4), kauno- ja tietokirjallisuudesta (6), lehtiteksteistä (30) ja lehtikirjoituksista (14). Toisena niin sanottuna vertailuaineistona käytetään Talko-tietokantaa, joka sisältää noin 1 000 suomenruotsalaisten käymää keskustelua. Kunkin keskustelun pituus on 40–60 minuuttia ja kustakin keskustelusta on litteroitu noin 20 minuutin mittainen osuus tietokantaan haettavaksi. Tutkielmassa käytetään 27:n suomenruotsissa esiintyvän suomenkielisen substantiivin sanavartaloita hakusanoina edellä mainituissa tietokannoissa. Tutkielman metodi on pääosin kvalitatiivinen, sillä tuloksia analysoidaan esimerkkilauseiden avulla. Toisaalta metodi on osittain kvantitatiivinen ja vertaileva, koska hakusanoista lasketaan prosenttiosuuksia ja aineistoja vertaillaan keskenään. Molemmat tutkimusaineistot osoittavat, että suomenruotsalaiset käyttävät suomenkielisiä substantiiveja pääsääntöisesti en-sukuisina tai niin, että substantiivit eivät kuulu kumpaankaan ruotsin kielen suvuista vaan esiintyvät virkkeissä perusmuodossa. Suomenruotsiin upotetut suomenkieliset substantiivit näyttävät myös usein mukautuvan ruotsin kielioppiin ja taivutusmalleihin. Toisaalta monikon epämääräinen muoto saa joidenkin hakusanojen kohdalla kaksi eri taivutusmuotoa. Puhutun ja kirjoitetun kielen erot ovat pienet. Suomenkieliset substantiivit esiintyvät kuitenkin perusmuodossa hieman useammin puhutussa kuin kirjoitetussa kielessä.
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(2013)I arbetet granskas det finska tillräknelighetsinstitutet ur ett de lege ferenda-perspektiv. Avsikten är att lyfta fram det finska tillräknelighetsinstitutets svagheter och skissa upp en ny modell för hur det borde se ut för att dessa svagheter skulle avhjälpas. För att hitta lösningar på det finska tillräknelighetsinstitutets problemområden, har jag gjort en jämförande analys av det norska tillräknelighetsinstitutet och det svenska påföljdssystemet för psykiskt störda lagöverträdare samt de svenska planerna på att återinföra tillräknelighet som en brottsförutsättning. Enligt finsk rätt saknar en otillräknelig gärningsman straffansvar. Om domstolen konstaterar att gärningsmannen var otillräknelig vid gärningstillfället, finns det inga påföljder som kan dömas ut domstolsvägen. Ansvaret övergår istället på psykiatrin som bestämmer huruvida gärningsmannen uppfyller kriterierna för vård oberoende vilja och kan tas in på en psykiatrisk anstalt. Om gärningsmannen har varit otillräknelig vid gärningstidpunkten men senare tillfrisknat från den psykiska störningen och därför inte längre har ett vårdbehov, uppfylls inte kriterierna för tvångsvård. Gärningsmannen går därmed fri. Nedsatt tillräkneliga gärningsmän är straffrättsligt ansvariga. Nedsatt tillräknelighet är en strafflindringsgrund men kan lika väl leda till fullt straff. Påföljderna för otillräkneliga, tillfrisknade otillräkneliga och nedsatt tillräkneliga skiljer sig markant även om gärningen bakom är den samma. Dessutom ligger påföljdsbestämningen i händerna på olika instanser, domstolarna och psykiatrin. I finsk rätt finns det inte heller någon möjlighet att beakta samhällets behov av skydd gentemot återfallsbenägna otillräkneliga gärningsmän. Detta rimmar illa med det allmänna rättsmedvetandet som inte kan acceptera att gärningsmän som begått allvarliga angrepp mot andras liv, hälsa eller frihet kan komma att inte omfattas av någon påföljd alls. Dessa omständigheter utgör svagheterna i det finska tillräknelighetsinstitutet. Genom en rättskomparativ analys till Norge och Sverige har jag granskat vilka lösningar de har kommit till ifråga om psykiskt störda och samtidigt återfallsbenägna gärningsmän. I båda länderna har behovet av samhällsskydd insetts och påföljdsbestämningen sker i domstolarna. I Norge kan allmänfarliga otillräkneliga gärningsmän dömas till en straffrättslig særreaktion medan psykiskt störda lagöverträdare i Sverige är straffrättsligt ansvariga. Sverige har nämligen frångått tillräknelighetsfrågan. I de planerade svenska förnyelserna är samhällsskyddet också ett genomsyrande tema. Ingetdera systemet är tillfredssällande som helheter. Genom att däremot använda mig av de grundläggande lösningarna beträffande samhällsskydd och domstolsprövning och genom att stöda mig på den norska och svenska argumentationen har jag tagit fram en ny straffrättslig påföljd för otillräkneliga, tillfrisknade otillräkneliga och nedsatt tillräkneliga gärningsmän. Den nya påföljden benämns vårdfängelse. Grundelementen i vårdfängelset är samhällsskydd, ändamålsenlig vård, rättsskydd och ett tillfredsställt allmänt rättsmedvetande.
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(2019)Syftet med avhandlingen är att studera hur familjevårdare upplever sitt nuvarande sociala nätverk samt hur nätverket förändrats till följd av att familjen börjat fungera i familjevård. Jag har sett på familjevårdares sociala nätverk och på det sociala stöd de får, för att ta reda på om stödet är tillräckligt och vad som eventuellt saknas. Studiens målsättning var även att lyfta fram familjevårdares egna erfarenheter och synpunkter angående deras sociala nätverk och behov av socialt stöd. Genom kvalitativa temaintervjuer har jag tagit del av åtta erfarna familjevårdares berättelser ur fem olika familjer. Intervjuerna har analyserats med hjälp av kvalitativ innehållsanalys, för att få fram synpunkter relevanta för min studie. Systemteori och social nätverksteori har tillämpats då jag analyserat intervjuerna. Jag har med andra ord utgått ifrån att nätverket är en helhet och att olika faktorer i nätverket påverkar varandra. Jag har även sett på funktionen och behovet av socialt stöd och hur detta har förändrats över tid. Familjevårdarna lyfte fram stora förändringar i det sociala nätverket. De betonade det positiva med ett nytt nätverk, så som nya kontakter och en möjlighet att få hjälpa barn. Samtidigt hade det ofta varit en stor förändring att släppa in myndigheter och professionella i sitt liv. Familjevårdarna uttryckte även svårigheter med att samarbeta med olika parter. De slutsatser som har kunnat dras utgående från analysen är att det sociala nätverket ofta genomgått stora förändringar både då en familj blivit fosterfamilj och även senare, då familjen fortsatt fungera i familjevård. Fosterbarnens behov förändras och familjen kan även få nya fosterbarn, vilket leder till nya behov av stöd. En fosterfamilj har andra kriterier för relationer och andra behov av socialt stöd än tidigare. Viktigt är att dessa behov uppfylls samt att de olika relationerna och stöden kompletterar varandra och tillsammans bildar en fungerande helhet. Ett fungerande samarbete med professionella inom socialvården är mycket viktigt för familjevårdare. Mer information om familjevård behövs i vårt samhälle. Detta kunde dels vidga synen på familjer och öka förståelsen, men även bidra till att hitta flera familjevårdare.
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