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The subject of our research is the behavior of the economy in response to monetary and technology shocks. To understand these issues we use a Dynamic Money-in-the-Utility-Function framework. We implement a non-separable property of the utility function that implies non-neutrality of real money balances. We construct a toy theoretic model with two representative agents who maximize their functions subject to constraints. We analytically solve the model using a method of log-linearization around the steady state and obtain the system of linear equations. We analyze the response of economic equilibrium with respect to implemented shocks using a method of undetermined coefficients and solve a system of linear difference expectation equations. In addition to analytical solution we also present Impulse Response Functions of the model. We compute the impacts of monetary and technology shocks on the model and find that in case of a positive monetary shock expected inflation effect dominates the liquidity effect, while in case of a positive productivity shock income effect dominates substitution effect. The findings regarding the impact of a technology shock contradict the theory of real business cycles that predicts the domination of substitution effect over the income effect

Dynamic scoring is an approach, which strives to take into account the effects that public policy changes and changes in the law have on the macroeconomic variables. Scoring is an estimate of the effects the policy change is expected to bring. Compared to the traditional approach, dynamic scoring offers more information of the effects, but does this with increased uncertainty. In their paper “Dynamic scoring: A back-of-the-envelope guide” (2006) N. Gregory Mankiw and Matthew Weinzierl use neoclassical growth model, or Ramsey growth model, to examine how large a part of capital and labor income tax cuts pay for themselves by inducing higher economic growth, i.e. the size of the dynamic feedback effect. Their focus is on the changes of tax revenue. They use first a basic model with Cobb-Douglas production and inelastic labor supply, then relax those assumptions for a more general Ramsey model and then in turn include parameters allowing for finite horizon households, imperfect competition, and externalities to capital investment. Depending on the model used, the dynamic feedback effect varies from model to model, for a capital tax cut from 50 to 74 percent and for a labor income tax cut from zero (with inelastic labor supply) to 21 percent. This thesis extends the Mankiw–Weinzierl model by including a tax on consumption to examine how this affects the dynamic feedback effect. In all the models, there is an increase in the dynamic feedback effect: depending on the model used, it varies for a capital tax cut from 60 to 87 percent and for a labor income tax cut from zero (with inelastic labor supply) to 25 percent. The values of some of the key parameters, namely the constant-consumption elasticity of labor supply and the elasticity of substitution between capital and labor, and the tax rates are revised as well. This further increases the dynamic feedback effect all along the line, in some cases even suggesting a capital tax cut to more than compensate the static revenue loss. Including a tax on consumption into the models increases the dynamic feedback effect, working into the same direction as rising the initial rates of capital and labor income taxes. Using alternative tax rates and values of the key parameters also has a significant impact on the size of the dynamic feedback effect.

The physiological effects of drought on trees has been studied excessively but many of them remain unclear. In this thesis I studied tree sugar dynamics under drying-wetting cycle as well as the role of soil hydraulic conductivity on how trees experience drought. I experimented with five Norway spruce seedlings in October and November 2016. The seedlings were in water after which they were put in to PEG solution of -0.5 MPa for 24 h and then transferred back to water. Sugar samples were taken from liquids, needles and roots once for every phase. Osmolality samples were taken from current year needles and water potential samples were taken from current year needles and roots every half an hour during day time. Continuous gas exchange measurements were done with Walz GFS-3000. There was no change in osmolality and no significant change in photosynthesis or transpiration rate. For sugar concentrations there was significant increase of non-structural carbohydrates in needles and significant decrease in roots. There was no change in sugar concentration in liquid. Overall impression was that trees did not suffer much from the PEG treatment. The results supported my hypothesis that changes in soil hydraulic conductivity are more important to effects of drought than changes in soil water potential.

Post-transcriptional modifications (PTMs) in RNA are present in all known RNA species and conserved in all kingdoms of life. Transfer RNA (tRNA) has been shown to have numerous conserved modifications, which exemplifies the importance of modifications having impact on the structure of the tRNA and its function as carrier of the amino acids. Ribosomal RNAs (rRNA) are universally modified as well, and modifications are situated at functionally important spots of the ribosome. Given the fact that types and sites of modifications are conserved, it is likely that these modifications have been selected for and that they optimize the ribosomal structure and functions. Stress, such as temperature or infection by a pathogen, is known to change the presence or abundance of modifications in RNA molecules and thereby affect translation efficacy. In line with that, this master’s thesis project sought to gain insight into the dynamics of PTMs in tRNA and rRNA upon oxidative stress, with the goal of utilizing recently optimized UPLC/MS method for identifying modified ribonucleosides. As the specific aim of the thesis was to estimate the change in PTMs in tRNA and rRNA in response to oxidative stress with 0.5 mM and 2 mM hydrogen peroxide H2O2, 3 immediate goals were: (i) to isolate total tRNA from yeast grown in stress conditions, (ii) to isolate rRNA from yeast 80S ribosomes, and (iii) to identify present modifications using mass spectrometry. Yeast was cultured in presence of H2O2 as a stressor in mentioned concentrations, and both treatments considered showed a difference in survival when compared to the control. Rough cell concentration estimates (OD600) did not show the effect of the stressor on cell survival clearly, but when number of viable cells per mL was estimated, it was clear that growth of the stressed yeast cultures was hindered 2 hours after exposure to H2O2 but recovered during the 24 hours. Firstly, using UPLC/MS analysis, 29 modifications were identified in tRNA from control and H2O2 treated yeast. Most identified modifications showed no change in abundance in treatments, which is to be verified with additional replicates. However, distinct dynamics of stress-related change was found for several modifications, revealing additional modifications that may play a role in stress related modificome reprogramming to the previously known signature modifications of oxidative stress. It was expected that recovery of culture growth after 24 hours may be accompanied with modification level recovery. However, that was not demonstrated here as downregulation at 2 hours followed by upregulation at 24 hours was seen for 2-methylthio-N6-methyladenosine, N4-acetylcytidine and 5-methoxycarbonylmethyl-2-thiouridine, and the reverse was shown for N4-methylcytidine. Upregulation in both time points was also shown here for some modifications. Taken together, these results confirm a complex and dynamic control of tRNA modifications in cellular survival responses. Modifications found to be affected by oxidative stress are most frequently located on the wobble position 34 and anticodon loop position 37, so it is expected that changes in their modification levels could directly affect the tRNA function in translation, making them a specific target for future research. Secondly, modifications in rRNA from control yeast cultures were identified, such as expected methylations of all 4 canonical nucleosides. However, further analysis will be needed to confirm the other identified modifications, due to the potential mRNA and tRNA contamination. Optimizing the method for rRNA modifications identifications by acquiring more modified nucleosides specific for the rRNA to use as standards in the analysis, analyzing rRNA types separately and using tandem mass spectrometry would enable getting a deeper understanding of which modifications are present and where they are positioned. Finally, it would enable reliable identification of the signals of novel modifications present in rRNA, such as the tRNA modification 5-carbamoylmethyluridine signal found here. In conclusion, this thesis work lays the foundation to study the evolutionary conserved function of PTM changes during stress as modulators of translation, using the methodological approaches discussed in-depth within the thesis, primarily to confirm the intriguing results found here.

In this thesis we consider dynamic X-ray computed tomography (CT) for a two dimensional case. In X-ray CT we take X-ray projection images from many different directions and compute a reconstruction from those measurements. Sometimes the change over time in the imaged object needs to be taken into account, for example in cardiac imaging or in angiography. This is why we're looking at the dynamic (something changing in time, while taking the measurements) case. At the beginning of the thesis in chapter 2 we present some necessary theory on the subject. We first go through some general theory about inverse problems and the concentrate on X-ray CT. We talk about ill-posedness of inverse problems, regularization and the measurement proses in CT. Different measurement settings and the discretization of the continuous case are introduced. In chapter 3 we introduce a solution method for the problem: total variation regularization with Barzilai-Borwein minimization method. The Barzilai-Borwein minimization method is an iterative method and well suited for large scale problems. We also explain two different methods, the multi-resolution parameter choice method and the S-curve method, for choosing the regularization parameter needed in the minimization process. The 4th chapter shows the materials used in the thesis. We have both simulated and real measured data. The simulated data was created using a rendering software and for the real data we took X-ray projection images of a Lego robot. The results of the tests done on the data are shown in chapter 5. We did tests on both the simulated and the measured data with two di erent measurement settings. First assuming we have 9 xed source-detector pairs and then that we only one source-detector pair. For the case where we have only one pair, we tested the implemented regularization method we begin by considering the change in the imaged object to be periodic. Then we assume can only use some number of consecutive moments, based on the rate the object is chancing, to collect the data. Here we only get one X-ray projection image at each moment and we combine measurements from multiple di erent moments. In the last chapter, chapter 6, we discuss the results. We noticed that the regularization method is quite slow, at least partly because of the functions used in the implementation. The results obtained were quite good, especially for the simulated data. The simulated data had less details than the measured data, so it makes sense that we got better results with less data. Already with only four angles, we cold some details with the simulated data, and for the measured data with 8 angles and with 16 angles details were also visible in the case of measured data.

Objective of the study. This Master’s thesis investigates dyslexic university students and their learning experiences. Previous research has shown that dyslexia is related to learning in a variety of ways. However, previous research is primarily focused on children and adoles-cents. Further academic studies set new types of requirements to learning. Thus, it is neces-sary to explore dyslexic university students in order to find out especially the factors that are impeding and enhancing their studies. Efficient progress and the completion of academic studies are important for the students themselves, but also for the university and the society. This research examines the obstacles that dyslexic students face during their studies, and the variety of means and practices they use to overcome these challenges. Methods. The research material consists of ten semi-structured theme interviews. In the in-terviews the students were asked about their study habits, how dyslexia appears in their studies, which impeding and enhancing factors they could name, and what kind of social support they have received during the studies. The interview data were analysed by using a qualitative abductive content analysis. Finally, four different student profiles were formed based on the analysis. Results and conclusions. Results of the study indicated, that the dyslexic students experi-ence various impeding and enhancing factors in their academic studies. In addition to the factors related directly to dyslexia, study exhaustion was named as a major impeding factor. Self-regulation skills, study engagement, and social support were considered to be the most central factors in overcoming those challenges. Student profiles provide direction for differ-ent measures of support. According to the results, the interventions that are most crucially needed relate to the development of self-regulation skills during the studies, and to recogniz-ing and reducing study exhaustion at their early stages.

Background Constipation and dyspepsia are disturbing gastrointestinal symptoms that are often ignored in research on physical comorbidities of schizophrenia. Aims Our aim was to assess dyspepsia and constipation in a sample of outpatients with schizophrenia spectrum psychoses. Methods A general practitioner performed a thorough physical health check for 275 outpatients and diagnosed constipation and dyspepsia. We assessed the possible contribution of several sociodemographic, lifestyle, and clinical variables to constipation and dyspepsia using logistic regression analysis. We also assessed whether these symptoms were associated with abnormal laboratory findings. Results The prevalence of constipation was 31.3%, and of dyspepsia 23.6%. Paracetamol (OR=3.07, 95% CI 1.34–7.02) and clozapine use (OR=5.48, 95% CI 2.75–10.90), older age (OR=1.04, 95% CI 1.01–1.06), and living in sheltered housing (OR=2.49, 95% CI 1.16–5.33) were risk factors for constipation. For dyspepsia the risk factors were female sex (OR=2.10, 95% CI 1.15–3.83), non-steroidal anti-inflammatory drugs (OR=2.47, 95% CI 1.13–5.39), and diabetes medication (OR=2.42, 95% CI 1.12–5.25). Patients with dyspepsia had lower hemoglobin and hematocrit and higher glucose values than those without dyspepsia. Patients with constipation had lower thrombocyte values than patients without constipation. However, these findings were explained by factors predisposing to constipation and dyspepsia. Conclusions Clozapine use markedly increases the risk of constipation and may lead to life-threatening complications. In addition, analgesics and diabetes medication were related to gastrointestinal symptoms. These medications and their association to gastrointestinal symptoms should be kept in mind when treating patients with schizophrenia.

Tämän kirjallisuuskatsauksen tavoitteena on kuvata dystrofiinin rooli ja merkitys lihaksen normaalissa toiminnassa, koota yhteen nykytietämys Duchennen lihasdystrofian patofysiologiasta sekä käydä läpi sairauden tutkimuksissa yleisimmin käytettäviä eläinmalleja. Duchennen lihasdystrofia on vakava, etenevä, perinnöllinen lihasrappeumasairaus, joka johtaa lihasheikkouteen, liikkumisen vaikeutumiseen, pyörätuolista riippuvuuteen, avustettuun hengitykseen ja lopulta ennenaikaiseen kuolemaan. Sairaus on poikalapsien yleisin neuromuskulaarinen sairaus, johon sairastuu noin 1/5000 syntyvästä poikalapsesta. Sairaus johtuu X-kromosomissa sijaitsevan dystrofiinigeenin mutaatioista, jonka seurauksena ei synny toimivaa dystrofiiniproteiinia. Ihmisten lisäksi homologiset sairaudet esiintyvät koiralla, hiirellä sekä kissalla. Dystrofiini ilmenee luusto- ja sydänlihaskudoksissa sekä pieninä määrinä aivoissa ja muualla kehossa. Lihassyissä dystrofiini sijaitsee lihassolukalvon alla, jossa se yhdistää solun tukirangan lihassolukalvoon sekä sitä ympäröivään tyvikalvoon. Dystrofiini muodostaa yhdessä muiden proteiinien kanssa dystrofiini-glykoproteiinikompleksin, joka toimii useissa tehtävissä solujen signaloinnissa sekä lihassolukalvon eheyden ylläpidossa lihassupistusten aikana. Ilman dystrofiiniä lihaksista tulee hyvin alttiita vaurioille, jonka seurauksena on etenevä lihaskudoksen korvautuminen side- ja rasvakudoksella, toiminnan heikkeneminen sekä kardiomyopatia. Sairauteen ei ole vielä olemassa parantavaa hoitoa, ja hoitojen tarkoituksena onkin oireiden kontrollointi sekä elämänlaadun parantaminen. Sairauden synnyn ja uusien hoitomuotojen etsimiseen hyödynnetään erilaisia eläinmalleja, joista osalla esiintyy spontaaneja mutaatioita dystrofiinigeenissä ja osa on geneettisesti muokattuja. Yleisimmin käytetyt eläinmallit ovat mdx-hiirimalli (engl. X-linked muscular dystrophy mouse) sekä kultaisennoutajan lihasdystrofia -malli. Dystrofiinin puutoksen aiheuttavia mutaatioita on kultaisennoutajan lisäksi todettu useilla muilla koiraroduilla, ja usein sairauden löytyminen uusissa roduissa on seurausta eläinlääkärissä heränneestä epäilystä.

Playing video games is a popular way to spend time and mobile gaming is one of the most growing entertainment industries in the world. Gaming is often associated with high level of motivation from the user as well as many negative and positive outcomes. Commitment towards games has invited countless of researches to examine what makes them so intriguing and motivating. This growing understanding gives developers more tools to design even better games and allows game-like features to be used in other contexts as well. This master’s thesis examines automatically gathered early log-data (n=100 000) from two free-to-play mobile games in order to create a model for retention. A model created using early log-data (first three days of play) creates opportunities to recognize potential players in an early phase and to evaluate early iterations of games that are in development. Furthermore, individual features are analyzed to study, what are the factors that influence coming back to the game at a later point (30 days after the installation of the game). The research questions in this thesis are: 1) Can commitment towards mobile games be modeled using early log-data? 2) How accurate predictions the created model can do? 3) What are the most important in-game features that predict retention? The model is created using a decision tree analysis, which was selected as a method due to its transparency and because it has been used before in earlier studies with similar designs. In both games, the rate of coming back to the game after 30 days of installation was 7.6%. A working model for retention was formulated which was able to predict coming back to the game with 33% accuracy. The most important in-game features that affect retention were the number of victories, the number of starts and the number of in-app-purchases during the three-day period after the game’s installation. Surprisingly, in-game rewards and achievements were the most insignificant features when predicting retention although they are often specifically designed to elevate user motivation. These results can influence design decisions made in game development by setting the focus on the factors that influence player commitment and behavior. Achievements and in-game rewards might feel too artificial and superficial compared to winning in game. If the system gives direct feedback of the effect of time and monetary sacrifice to the player’s performance, one might be able to reduce the number of players that decide to leave the game. The results also can be used to examine how game-like features are used in non-game systems where the goal is to tie together the high-level of motivation seen in games and socially impactful endeavors. Further studies of in-game behavior might also give new insights on game addiction and its negative effects on player well-being and business.

Tutkielma käsittelee toiminnallisia tehtäviä varhennetun englannin opetukseen suunnatuissa oppikirjoissa Jump in ja Go. Vuosiluokkien 1-2 A1-kielen opetussuunnitelman perusteissa korostetaan, että opetuksessa tulisi korostua toiminnallisuus ja työtavoissa tulisi yhdistyä leikinomaisuus, musiikki, draama, pelit ja liike sekä eri aistien hyödyntäminen. Tutkielman tarkoituksena on selvittää, miten paljon ja millaisia toiminnallisia tehtäviä varhennetun englannin oppimateriaaleissa on, sekä millaisia elementtejä nämä toiminnalliset tehtävät sisältävät. Aiemmat tutkimukset ovat osoittaneet, että toiminnalliset työtavat voivat tukea oppimista ja ovat myös varhennettua kieltä opettavien opettajien suosimia tehtävätyyppejä. Aineistona tutkimuksessa käytettiin Otavan Jump in -oppimateriaalia sekä Sanoma Pron Go -oppimateriaalia, jotka on molemmat suunnattu varhennetun englannin opetukseen. Tutkielmassa analysoitiin oppilaille tarkoitettuja oppikirjoja sekä opettajan digiopetusmateriaalia, mutta vain oppikirjojen sisältämät tehtävät analysoitiin yksityiskohtaisesti. Oppikirjojen toiminnalliset tehtävät analysoitiin fokusoiden niiden sisällöllisiin elementteihin. Analysoidut sisältöelementit olivat liike, musiikki, kirjoittaminen, lukeminen, draama sekä värittäminen/piirtäminen. Pelit luokiteltiin toiminnallisiksi tehtäviksi, mutta ne analysoitiin erikseen niiden suuren määrän vuoksi. Tutkimuksen pohjalta voidaan todeta, että molemmat oppimateriaalit sisälsivät toiminnallisia tehtäviä, mutta tehtävät ja niiden elementit olivat erilaisia. Liike ja puhuminen olivat yleisimmät elementit toiminnallisissa tehtävissä, kun taas peleissä puhuminen oli yleisin elementti. Oppimateriaalien välillä oli myös eroavaisuuksia, sillä Go -oppikirjan toiminnalliset tehtävät sisälsivät enemmän draamaelementtejä, kun taas Jump in -oppikirja otti paremmin huomioon oppilaat, joiden lukutaito ei ole vielä vahva.