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Background Short-chain fatty acids (SCFAs), such as butyrate, acetate and propionate, mainly originate from dietary fibre fermentation in the colon. In recent years, additional gastrointestinal (local) and systemic effects of SCFAs have been observed in vitro and in both animals and humans in vivo. Faecal SCFAs have been associated with several conditions and diseases, including irritable bowel syndrome, type 2 diabetes, colorectal cancer, and cardiovascular diseases. Aim(s) The BEAN MAN study was carried out to assess the effects of the partial replacement of red and processed meat with legumes on nutrient intake, nutritional status, and the risk factors of type 2 diabetes, colorectal cancer and cardiovascular diseases. This thesis was part of the BEAN MAN study and investigated the effects of partially replacing red and processed meat with legumes on the concentration and composition of faecal SCFAs in healthy, working-age Finnish men. As a secondary outcome, the intake of dietary fibre and soluble polysaccharides were assessed and correlations between the total and individual SCFAs were analysed. Methods The BEAN MAN study was a 6-week randomized dietary intervention, with two diet groups in a parallel design. The Conventional Finnish diet group (Conventional FIN) was given 760 g/week of red and processed meat, corresponding the average meat consumption of Finnish men. The Flexitarian/Legume group (Flex/Leg) received 200 g/week of red and processed meat, and legume products to provide an equal amount of protein as 560 g of red meat. The faecal samples obtained from the participants before and at the end of the intervention period were freeze-dried, and SCFA were extracted and analysed using gas chromatography. Dietary fibre intake was analysed based on 4-day food records. Results At the endpoint, no significant differences in total (p = 0.560) nor individual SCFAs concentration and composition between the two diet groups were observed (ANCOVA, baseline as a covariate). The dietary fibre intake of the Flex/Leg group was higher (p < 0,001) when compared to the Conventional FIN. This was not the case for soluble polysaccharides. No correlation between the dietary fibre intake and the concentration of total or individual SCFA was found. Conclusion The concentration and composition of faecal SCFAs were not significantly affected by the partial replacement of red and processed meat with legumes during the 6-week intervention. This may highlight a more complex relationship between diet, microbiota and the production of SCFA.

Objectives: Low birth weight has been associated with impaired cognitive abilities especially in childhood and young adulthood. However, the role of a low Apgar score on cognitive functions remains unclear. Apoliprotein E (APOE) gene allele ε4 has been linked to older people’s cognition, but the influence of APOE alleles on cognition of children or middle-aged is not well understood. The present study investigated the effects of low birth weight (< 2000 g) and low Apgar scores (< 7) on later cognitive performance and on the stability of cognitive functions from childhood to middle age. In addition, the influence of APOE ε2 and ε4 alleles on risk group subjects’ cognitive performance was evaluated. It was hypothesized that the groups with perinatal risk factors have impaired cognitive abilities in all the domains and have lower stability within these abilities compared to controls. Low birth weight was hypothesized to contribute lower cognitive abilities more than a low Apgar score. It was also assumed that APOE ε4 allele impairs cognitive performance only at midlife, not in childhood. Methods: The subjects with low birth weight (n = 66) and/or a low Apgar score (n = 60) were selected from a birth cohort born during 1971–1974. The control subjects (n = 95) were free from perinatal risk factors. Cognitive performance was evaluated using Wechsler’s intelligence test. All the subjects completed the test at the age of 40 (n = 221) and some also at the age of 9 (n = 190). The differences between the groups were computed with the analysis of covariance, where family socioeconomic status was controlled. Differences in the stability of cognitive abilities were evaluated with repeated measures ANOVA and correlation analysis. The effect of APOE ε2 and ε4 alleles on cognitive performance was computed with t-test. Results and conclusions: The subjects with low birth weight reached lower scores in all the cognitive domains compared to controls. At midlife, there was also a trend towards lower general intelligence in individuals with a low Apgar score. The lowest stability in cognitive performance between childhood and middle-age was observed among those born with a low birth weight. However, the difference in the stability was not significant between the groups. APOE ε4 allele was related to lower ability of perceptual reasoning in childhood and middle age. According to the results, the effects of low birth weight on cognitive functions seem to extend to middle age. However, it is assumed that environmental factors have an important role in later development in people with low birth weight. Based on the results, the APOE ε4 allele might impact already on early cognitive development. In the future, it is important to examine if this initial impairment in perceptual reasoning is related to abnormal aging among those with APOE ε4 allele.

Suot ovat tärkeä osa maailmanlaajuista hiilen kiertokulkua, koska ne varastoivat suuria määriä hiiltä eloperäiseen materiaaliin turpeen muodossa, joka muodostuu biomassan hitaasta hajoamisesta kylmän, hapettoman ja matalan pH:n ympäristön vuoksi. Soista vapautuu myös metaania (CH4), joka on voimakas kasvihuonekaasu, jonka lämmityspotentiaali on 28 kertaa voimakkaampi kuin hiilidioksidin (CO2). Turvemaiden netto-C-päästöt riippuvat suotyypistä ja ympäristöolosuhteiden muutoksista, kuten pohjaveden korkeudesta tai turpeen lämpötilasta, ja niistä johtuvasta tasapainosta CH4-päästöjen ja turpeen muodostumisesta johtuvan hiilinielun välillä. Tämän tutkimuksen tavoitteena oli selvittää, miten kasviyhteisöt ja muut säätelevät tekijät, kuten lämpötila, pohjaveden korekus, LAI ja suotyyppi vaikuttavat sekä ilmakehän hiilivirtaan että turpeen CH4- ja CO2-pitoisuuksiin. Lisäksi tehtiin stabiiliin hiili-13 isotoopin mittauksia, jolla saadaan lisätietoa metanogeneesin biogeokemiasta. Mittaukset otettiin rahkasammalvaltaisista mättäistä ja saravaltaisista välipinnoista. Mittauspisteille tehtiin kolme kasvillisuuden manipulointia, joilla selvitettiin kasvillisuuden vaikutuksia hiilidynamiikkaan 1. putkilokasvien ja sammaleiden poisto, 2. pelkkä putkilokasvien poisto, 3. Kaikki kasvillisuus tallella. Tutkimuspaikka sijaitsee Etelä-Suomessa Siikanevan suoalueella. Mittaukset tehtiin vuonna 2018 touko-syyskuussa ombrotrofisessa keidasrämeessä ja oligotrofisessa saranevassa. Mittauskausi oli poikkeuksellisen kuiva ja pohjavedenkorkeus oli keskiarvoa matalammalla. Tästä johtuen monia aikaisemmin havaittuja korrelaatioita ei löytynyt. CH4-virtojen suuruus riippui suotyypistä ja kasvillisuuden manipuloinnista. Keskimääräiset turpeen CH4 ja CO2 pitoisuudet olivat hieman korkeammat mittauspisteissä saranavevalla. Pitoisuudet kasvoivat nopeasti syvyyden myötä, 50 cm:n syvyydessä pitoisuudet olivat useita suuruusluokkia suurempia kuin 7-20 cm:n syvyyksissä korkeimpien, mittausten ollessa yli 500 000 ppm. δ13C-CH4-arvot muuttuivat negatiivisemmiksi tyypillisesti syvyyden myötä, kun hydrogenotrofinen metanogeneesi yleistyi. Kasvillisuuden manipuloinneilla oli vaihtelevia vaikutuksia CH4-vuohon, eikä lehtipinta-alaindeksi osoittanut vahvaa lineaarista korrelaatiota CH4:n kanssa. CH4-virtaus oli myös epäherkkä pohjaveden korkeudelle, mutta kasvien välittämä CH4-kuljetus ei todennäköisesti ollut syynä, koska kasvillisuuden poistokäsitellyt mittauspisteet osoittivat myös samanlaista epäherkkyyttä veden korkeudelle. Putkilokasvien ja sammaleiden poistaminen vähensi yleensä CH4-virtoja. Mättäissä, joissa putkilokasvit oli poistettu, mutta sammaleita ei, oli alhaisimmat CH4-virrat. Yhteenvetona voidaan todeta, että useimmat ympäristömuuttujat eivät osoittaneet vahvaa korrelaatiota CH4:n kanssa. Mikään yksittäinen muuttuja ei selittänyt selvästi eroja CH4-vuossa. Turpeen CH4 ja CO2 pitoisuudet riippuvat voimakkaasti syvyydestä ja suotyypistä. Kasvillisuuden poistaminen tyypillisesti vähensi CH4-virtoja.

Aims of the study. Evidence suggests that a slow breathing method called resonance frequency breathing may improve sleep quality, but many previous studies have suffered from methodological shortcomings. Music listening is a popular self-help strategy to promote sleep, but previous research assessing the efficacy of music in improving sleep has yielded inconsistent results. Sleep is known to promote the retention of newly learned material, but the effects of slow breathing and music listening on overnight declarative memory consolidation are unknown. This study explores the effects of two interventions, slow breathing approximating resonance frequency and music listening, on objective sleep quality and overnight declarative memory consolidation. Methods. This study was a randomized, controlled trial with a crossover design. 20 participants (10 females) were randomly allocated to an experimental group, who did a 30-minute slow breathing exercise, or a comparison group, who listened to relaxing music for 30 minutes. Participants’ sleep was measured on two consecutive nights with polysomnography. On one night, participants completed their assigned intervention before going to bed; the other night was used as a no-treatment control condition. Memory performance was measured with a word pair association task. Linear mixed-effects modeling was used to analyze the data. Results and conclusions. Slow breathing improved declarative memory performance, but it did not improve sleep quality when compared to the control condition. Music listening did not affect memory performance, but it improved sleep quality as manifested in reduced wake after sleep onset, decreased duration of stage N1, stage N2, and non-REM sleep, and an increased percentage of stage N3 sleep when compared to the control condition. The results suggest that music listening can improve objective sleep quality and slow breathing can promote overnight learning, but more research is needed to understand the exact mechanisms underlying these associations.

School choice was introduced to the current comprehensive schooling system in Finland during the mid-1990s as a result of several small policy changes. Student sorting is still mainly based on proximity, but students are allowed to apply to another school. The ease of applying and being accepted into other than your assigned school varies between municipalities. Even though the proportion of students exercising choice is considerable, the effects of the Finnish reform are relatively understudied and the research is mostly conducted by educational scientists, leaving out the logic of economics through which school choice was originally justified. The purpose of this thesis is to study the effects of school choice on segregation of schools using joint application data of ninth graders ending comprehensive school and applying to secondary education in 1996 to 2004. Segregation of schools is measured over time at municipal level using municipalities with at least two schools. The very well-known Duncan index and variation between schools are used to measure segregation of schools. Also, isolation index is used to measure segregation of schools by foreign speaking students. Indices are adjusted to measure segregation from randomness. The development of these measures is studied more closely for the Capital City region. In addition, fixed effects model is used to explain the segregation indices by the share of students attending local school and residential segregation. Segregation increases steadily from 1996 to 2004 in Helsinki by high school attendance, high school graduation and GPA. Segregation is lower and stays almost constant for Vantaa, where school choice has been more limited from the beginning. All measures for segregation of schools by foreign students for Helsinki and Vantaa are somewhat inconclusive. Using municipality fixed effects model to explain segregation indices by schools’ share of local students and residential segregation indicates that in cities with high share of students attending their neighborhood school segregation of schools by high school attendance and graduation decreases. However, results are insignificant for the rest of the measures and it seems that residential segregation explains the segregation of schools for all measures. Fixed effect model may suffer from endogeneity. The results indicate increasing segregation of schools by ability in Helsinki after the reform and the fixed effect model to some extent supports these findings. Measures are still quite moderate. More data on before the reform is required to make any causal interpretations on the effects of the school choice reform. The evidence suggests that the underlying residential segregation plays a key role in segregation of schools. School choice is believed to alleviate the pressure of ‘selection by mortgage’. Therefore, the effects of the reform on residential segregation should be studied before we consider limiting school choice in Finland.

My master’s thesis aims to determine the impact of soil treatments and the hemi-parasite Rhinanthus minor (yellow rattle) on the soil properties of newly established perennial wildflower meadow. As urbanization and urban green spaces increase, the need for viable methods for establishing biodiverse meadows on existing lawns grows. I joined a lawn to meadow project based at Lammi Biological Station wherein four soil treatments (untreated, scarified, overturned, and replaced with meadow substrate) were employed in eight meadow blocks. Within those blocks, yellow rattle was sown into half of the plots to determine if it can hamper the growth of competitive grass species. My aim was to explore the meadow blocks’ chemical soil properties (phosphate, nitrate + nitrite, ammonium, total carbon, total nitrogen, and pH). The soil properties were measured using LECO analysis, photometric analysis, and a pH meter. In the newly established meadows at Lammi biological stations, there is evidence that soil properties do change as a result of different soil treatments and the introduction of a hemi-parasitic plant. The initial soil properties show that soil turnover results in increased nitrate + nitrite and decreased total nitrogen compared to untreated meadow soil and lawn controls, respectively. Meadow soils replaced with a substrate exhibited nutrient poor conditions typical of low nutrient preferring meadow plants. The effects of yellow rattle on aboveground community structure are not investigated here, but after the first growing season, its presence increased nitrate + nitrite in the first ten cm of soil. Nitrogen mineralization as a result of grass introduced to soil microbes and nutrient dense yellow rattle leaves may be the cause of these changes to the soil properties. Meadow establishment can take 3 – 5 years, so the use of these methods should continue to be observed. I would expect larger differences to manifest as the experiment continues, namely, decreased soil nutrients as more growing seasons pass.

Biochars are soil amendment materials produced via pyrolysis of biomass. They are resistant to degradation and can be used as a way to sequester carbon from the atmosphere. Biochars can improve soil structure and water and nutrient retention capacity, and significant positive effects on soil aggregate stability, water retention capacity and nutrient availability have been observed in acidic soils with low carbon content. The positive effects of biochar on soil properties can also increase crop yields. However, most studies on the effects of biochar have been conducted in tropical or temperate climates, and currently very little is known on its effects on the yield formation of cereals, and more specifically, barley. The aim of this study was to determine the effects of softwood biochar on field soil moisture and nutrient contents, as well as its effects on yield components of barley (Hordeum vulgare L.) 8 years after its application (0, 5, 10, 20 and 30 t ha-1) to boreal soil. In addition, the effects of organic and mineral fertilizers, alone and together with biochar, on soil moisture, nutrient contents and barley yield components were studied. Biochar did not have significant effects on soil moisture or nutrient contents or on barley yield components. Fertilization had significant effects on contents of soil moisture and nutrients, electrical conductivity, pH and the biomass, leaf chlorophyll content, number and weight of seeds and the final yield of barley. The non-significant effects of biochar can be due to the high amount of carbon already present in the soil, and similar results have been observed on the research site in previous years. The added biochar may also have been misplaced by soil management or degraded by weathering. The growing season of 2018 was drier and warmer than the long-term average and drought during the beginning of the growing season combined with issues with weeds negatively affected crop development and yield components.

Osprey Pandion haliaetus has been under a strict surveillance of the nature conservationists and a conservation icon since the early 70’s. At that time the accumulation of persistent environmental toxins and pollutants lowered the populations of many birds of prey to low levels, threatening the survival of entire species. Nowadays osprey is one of the successful models of endangered species protection. Because of its status osprey is very thoroughly studied raptor. Due to environmental toxins many birds of prey suffered from eggshell thinning and lost clutches till the end of 1970’s. Eggshell thinning has later stopped and is now reverting, but after the start of intense studying of the birds other threats have been observed to reduce reproductive success. Many earlier studies have suggested that extreme weather conditions may have an effect on the nesting success of diurnal birds of prey. In osprey´s case many researchers have examined the effects of different weather patterns to foraging success and food delivery, but a specific review over their effects on the nesting success hasn’t been conducted so far. In this study I focus on the effects of different weather factors and their contemporary nesting success. I study a nature conservation based supplementary feeding pond‘s effect to the local osprey population’s reproductive success, combined with the weather variables and the density of nesting pairs. Osprey is recorded to fly approximately 3–15 km on its foraging trips. At their longest these fishing trips can be over 40 km long one-way. The Osprey Center, working in Pohtiolampi at Kangasala (61° 26.876' N, 24° 7.705' E), in Southern Finland, feeds the local ospreys with living rainbow trout from an old fish farm pool. In theory, the birds nesting or living near the supplementary feeding pond benefit from this in a form of easy sustenance. The fish move near the water surface and are thus available all the time. Especially during bad weather conditions the pond is frequently visited by nesting ospreys. In this study I examine 1) does supplementary feeding have an effect on the nesting success of the local osprey population, 2) what is the role of weather factors affecting the breeding success and 3) does supplementary feeding have an effect on nesting density? I used 16 years of weather and breeding data (1997–2012) and evaluated the individual and combined weather variables and their possible effects on nesting success and brood production, comparing study and control area. I set my study area in a shape of a circle with 30 km radius. Pohtiolampi feeding pond was placed in the center of the study area, surrounded by a vast labyrinthine lake area. For the control area’s and study area's ecosystems to be as much alike as possible, I established the control area, also in a form of a circle and continuing the next 30 km, to start where the study area ended (see: Map 1.). I calculated the covariance and Akaike weights of different weather variables and annual nesting success with R (2.15.0) statistical calculation program. Collinearity was assessed with variance inflation factors (VIF). Generalized linear mixed models (GLM), to asses simultaneously the role of weather variables and the nesting success of both study and control area, were used. Finally the scenarios were arranged in significance order by their AICc values (Akaike information criterion adjusted for finite sample size). After the comparing analysis, I repeated the calculations also without the division to study and control area, gaining information about the effects of weather variables in general. I also calculated the proportional effects of different land use types to the nesting density of the local osprey population by using ArcGIS mapping tool and compared the results between study and control area. My results indicate that supplementary feeding does not influence the nesting success. Same annual average of young fledged the nests each year, regardless of the area. Weather variables, however, showed some effect on the nesting success when viewing the entire population. The assembled weather data shows examples of weaker nesting success in summers with prolonged storms, rainy weather or low average temperature. However, levels of significance, derived from the data, are still too low to be used as generalizations. Only three day long storms had a better AIC weight than the null model. I presume that the good fishing waters, wind shelter and shoreline forests are possible explanations to this trend. Most harmful weather to the osprey nestlings was a prolonged storm (? 7 m/s wind) and rainy summers. The nesting density of osprey was recorded to be significantly higher in the study area than in the control area, when viewing the total land acreage. Moreover, I recorded that the density in the study area grew up to almost four times the number of control area, when studying the acreage of potential nesting areas. When viewing the area of foraging waters the difference was reduced to 1.5 fold. I conclude that the local osprey population benefits from the supplementary feeding area by nesting more densely near the abundant food source and thus producing more young per km².

During the past decade, central banks have become even more central to modern economies than before. Their main goal is price stability, and they try to achieve it with various methods. The effectivity of the traditional methods, especially controlling the short-term interest rates, has become smaller due to the zero lower bound constraint, and new unconventional methods have been introduced. This thesis investigates the effects of the unconventional monetary policy actions of the European Central Bank. Structural vector autoregressive models are one of the main tools in studying the effects of the monetary policy. To identify a monetary policy shock, one traditionally needs to impose restrictions to the model. However, that requires restrictive assumptions about the dynamics of the model which is being studied. To overcome this issue, one can identify the shocks statistically by some properties of the data, without any additional restrictions. A key benefit of statistical identification is the possibility to test the plausibility of previously used sign or zero restrictions. In the empirical application of this thesis, a Bayesian vector autoregressive model identified statistically based on non-normality of the error terms is utilised to study the effects of the European Central Bank's unconventional monetary policy. The Bayesian estimation was performed with a Differential Evolution Markov Chain algorithm, allowing fast calculation. The empirical analysis resulted in two key findings. First, the impulse response functions implied by the model are in line with previous studies and the statistically identified model gives support to the previously used sign restrictions. Second, the model is sensitive to the sample period which suggests that the effects of the European Central Banks policy actions might have changed over time.

Transcranial direct current stimulation (tDCS) is a method that in recent years has gained the attention of researchers. In certain contexts, tDCS can be utilised in modulating brain function and cognitive performance, and it has been found to modulate symptoms and neural correlates of some pathologies. Due to differences in protocols between studies, the literature is inconclusive on the effects of tDCS on some brain areas and networks. In this study the effects of tDCS directed to medial prefrontal cortex (mPFC) on functional networks of the brain in resting state are examined. 36 healthy female subjects were divided into control and tDCS-groups of equal sizes. Functional networks were examined using functional magnetic resonance imaging (fMRI) in resting state before one stimulation session of 20 minutes with 2 mA current or sham stimulation, and after the session. Functional networks were identified with independent component analysis (ICA), which was performed on the set of images with both groups combined. The groups were then compared on a network level. The tDCS group showed increased functional connectivity in and around the left anterior cingulate cortex (ACC) in language network compared to the sham group. Other networks identified by ICA that showed no statistically significant differences between groups were posterior and anterior default mode, dorsal attention, sensorimotor, orbitofrontal, left and right frontoparietal, medial and lateral visual network, basal ganglia and the cerebellum. The results of this study were partially in line with previous studies that have found increases in the functional connectivity of brain regions associated with reward processing. There is a need for systematic examination of the effects of different tDCS protocols on functional networks in future studies.