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Bioprinting has emerged as a cutting-edge technology to overcome the shortage of tissues and organs by the precise deposition of living cells and biomaterials into three-dimensional (3D) biomimetic constructs. However, the inadequate choice of bioinks has limited its widespread implementation and clinical transformation. Natural polymers, such as chitosan and alginate, are commonly used as bioinks due to their biocompatibility, biodegradability and similarity to extracellular matrix (ECM). These natural polymers are usually limited by their mechanical strength and have less tunable mechanical characteristics. Instead, synthetic polymers offer adjustable mechanical properties and good printability, and they are often used as sacrificial materials in 3D bioprinting. Hybrid hydrogels consisting of Pluronic F127 (PF) and natural polymers have been suggested to have good printability and rheological behaviors. However, PF tends to be cytotoxic at concentrations required for good printability. Another synthetic copolymer which comprises poly(2-methyl-2-oxazoline) (POx) (A-block) and poly(2-n-propyl-2-oxazine) (POzi) (B-block) was investigated as the potential alternative for PF. In this work, two different hybrid platforms consisting of synthetic POx-b-POzi /natural polymer (chitosan or alginate) and PF /natural polymer (chitosan or alginate) were formulated. The main focus of the study were on their printability and the potential of POx-b-POzi to replace PF as a sacrificial material in 3D bioprinting. POx-b-POzi and PF-based hybrid hydrogels were formulated and their printability was evaluated by rheology, mechanical compression, and 3D printing and printability assessment tests. The results showed that both POx-b-POzi and PF based hybrid hydrogels can be printed into different 3D structures, and the printed structures were successfully crosslinked. Although, the printability assessment tests and rheology showed that PF based hydrogels exhibits greater printability, POx-b-POzi also meets the critical requirements for bioinks.

Recent studies have suggested that iron (Fe) and manganese (Mn) oxides may play a role in the anaerobic oxidation of methane (AOM) in brackish coastal sediments of the Baltic Sea. However, the distribution of these oxides in coastal sediments had not yet been established. In this study sedimentary Fe and Mn dynamics were studied along Pohjanpitäjänlahti which is a silled estuary and the adjacent archipelago in Uusimaa, Finland. The estuary is fed by Fiskarinjoki and Mustionjoki rivers and it discharges into the Gulf of Finland through a narrow, salinity stratified strait. Sediment and porewater samples for chemical profiling were obtained by GEMAX™ coring, sediment slicing and Rhizon™ porewater extraction. Water samples were obtained by Limnos™ water sampler and analyzed for dissolved Fe and Mn. Concentrations of Fe and Mn and speciation of sediments were determined by sequential extraction, including a separate extraction scheme for sulfur-bound phases. The results of this study show that the distributions of iron and manganese are heterogeneous in the coastal zone of the Gulf of Finland. Dissolved Fe concentration decreases rapidly from the river mouth due to salinity induced flocculation and sedimentary Fe concentration decreases steadily offshore. In contrast, dissolved and sedimentary Mn concentrations are highest in the deep inner basin of Pohjanpitäjänlahti. This implies internal shuttling of Mn related to redox conditions in the estuary. The Fe and Mn speciation of inshore sites is dominated by more reactive phases such as poorly-crystalline and crystalline oxides, while at offshore sites, less reactive phases such as sheet silicates are more dominant. Fe and Mn oxides are present in all study sites throughout the sediment cores which make them theoretically available for Fe-Mn- mediated AOM.

Long wave (LW) radiation in the Earth's atmosphere is defined as the radiation at wavelengths longer than 4 µm (infrared). The short wave (SW) radiation wavelengths are less than 4 µm (visible light, ultraviolet). SW radiation is usually from solar origin. The absorbed solar SW radiation is closely balanced by the outgoing LW radiation in the atmosphere. This radiation balance keeps the global average temperature stable. The main cause of the current global warming trend is human expansion of the 'greenhouse effect'. Atmospheric greenhouse gases absorb the thermal LW radiation from a planetary surface. The absorbed radiation is re-emitted to all directions. Some of the energy is transferred back to the surface and the lower atmosphere since part of the re-radiation is directed towards the surface, resulting in increased surface temperature. The local radiation balance is also affected by clouds and aerosols in the atmosphere since they too can absorb and scatter radiation. The effects of clouds and greenhouse gases on the global radiative balance and surface temperature are well known. The aerosols, however, are one of the greatest sources of uncertainty in the interpretation and projection of the climate change. Natural aerosols such as those due to large eruptions of volcanoes and wind-blown mineral dust are recognised as significant sources of climate forcing. In addition, there are several ways in which humans are altering atmospheric aerosols. These include industrial emissions to the lower atmosphere as well as emissions to as high as lower stratosphere by aircraft. In this thesis the effect of aerosols on LW radiation was studied based on narrowband LW calculations in a reference mid-latitude summer atmosphere with and without aerosols. Aerosols were added to the narrowband LW scheme based on their typical schematic observed spectral and vertical behaviour over European land areas. This was found to agree also with spectral aerosol data from the Lan Zhou University Semi-Arid Climate Observatory and Laboratory measurement stations in north-western China. A volcanic stratospheric aerosol load was found to induce local LW warming with a stronger column “greenhouse effect” than a doubled CO2 concentration. A heavy near-surface aerosol load was found to increase the downwelling LW radiation to the surface and to reduce the outgoing LW radiation, acting very much like a thin low cloud in increasing the LW greenhouse effect of the atmosphere. The short wave reflection of white aerosol has, however, stronger impact in general, but the aerosol LW greenhouse effect is non-negligible under heavy aerosol loads.

Population growth and the conversion of forests to agricultural lands is a typical phenomenon in the highlands of East Africa. Land use changes set pressure on ecosystem services and natural resources, such as fresh water, which is essential for human well-being. Soil forms the largest free fresh water storage on planet. To maximize the potential of groundwater reservoirs in a continually changing environment it is extremely important to understand the factors controlling the infiltration process. The effect of land use on infiltration has been studied broadly but due to the increasing water scarcity and difficult geographical accessibility, the amount of infiltration studies conducted in the highlands of East Africa is low. The aim of this study was to examine whether land use affects infiltration in Taita Hills (3°25' S, 38°20' E), a tropical highland environment in southeastern Kenya, and whether the changes can be explained by the changes in soil properties. Another aim of this study was to examine whether the collected field infiltration data can be modelled with fixed infiltration models, which could potentially decrease the need for time and water consuming field infiltration measurements in future. This study focused on three land use classes: forests, cultivations and grazing lands. The collected field data consisted of field infiltration measurements (n=50) and corresponding soil organic carbon, soil organic nitrogen, soil bulk density, soil moisture and soil texture samples. The effect of land use on infiltration was examined with the one-way ANOVA and pairwise t-test. The relationship of soil properties and steady state infiltration rates was investigated with simple linear regression models. According to the results of this study infiltration rates vary by land use. The mean infiltration rates were 3900, 1700 and 450 mm/h in forests, cultivations and grazing lands, respectively, which correspond a decrease of 59 % and 88 % in infiltration rates when forests are converted to cultivations and grazing lands, respectively. According to the produced simple regression models soil bulk density explains 61.5 % and soil organic carbon and soil organic nitrogen 24.0 and 34.1 % of the variation of infiltration rates, respectively. Initial soil moisture explained 15.6 % of the variation but is believed to reflect the climatic and structural conditions of the soil instead of representing a direct impact on the infiltration process. The results suggest that soil texture does not explain the variation of infiltration, which is most likely due to the homogenous soil across the study area. Horton's infiltration model was found most suitable to model the infiltration process within the study area, although the overall performance of the models of Philip and Green and Ampt were also sufficient. The Modifield Kostiakov model was not found suitable to model the infiltration process of the study area.

As a full-grown science, cosmology is relatively young. Even though man has pondered the existence and structure of the universe throughout his history, the lack of actual observational data has prevented analytical research. Observational cosmology can be seen to have born in the 1920’s when Edwin Hubble discovered that the galaxies surrounding us are receding in all directions. This led to the conclusion that the universe around us is itself actually expanding. Expansion occurring isotropically in all directions indicates that the universe was once much denser and hotter. So hot that the matter in it has been completely ionized plasma. The decrease in temperature caused by the expansion is calculated to have caused the neutralizing of the plasma, recombination, over thirteen billion years ago. The instant is cosmologically remarkable, since light that until that moment scattered frequently from the charged particles now began to propagate freely. Initially at three thousand Kelvin temperature, the radiation has cooled down due to expansion and is now observed as the three Kelvin cosmic microwave background radiation (CMB). First observations of the existence of the CMB date back to 1965. Since the background radiation has traveled its long journey relatively unchanged, its study can yield direct information on the conditions of the early universe. Theoretically it was expected, well before observational confirmation in 1992, that the CMB should have a structure that reflects those inhomogeneities, that have now undergone their ten billion years of evolution, to become the large scale structure we observe: galaxies, galaxy clusters and the evermore larger entities. In this thesis we examine, how the effects of two cosmological parameters, the matter and baryon densities of the universe, manifest in the pre-recombination dynamics and how these effects are reflected in the structure of the observed CMB anisotropy. Baryons are the “ordinary” matter all around us, protons and neutrons. The concept of “matter” is extended to include the unknown dark matter, the existence of which is only known through its gravitational effects. We will review the equations that are necessary to track the evolution of the primordial perturbations. By a computer program based on those equations we display how the early universe dynamics change with the values of the density parameters. Finally we will show how these effects are reflected in the angular power spectrum that describes the structure of the microwave background.

Air pollution is the most severe environmental problem in the world in terms of human health. The World Health Organisation (WHO) estimates that 91% of the world's population is exposed to high air pollutant levels. The risks are particularly high in urban areas, where often high population densities are combined with high air pollutant levels. Urban street canyons are especially prone to high pollutant levels due to the proximity of traffic and reduced exchange of air with the street canyon and air above, referred to as ventilation. As a result, one of the most important topics in city planning is how to avoid designs that impact the air quality negatively. Street trees are often planted in street canyons for aesthetic purposes while they can also improve thermal comfort. The air quality within street canyons is affected by street trees in two ways. They provide leaf surface for air pollutants to deposit on, thus cleaning the air. On the other hand, they block the airflow within the street canyon, thus decreasing the ventilation of air pollutants. In previous studies the latter effect has generally been found stronger. However, due to the various benefits of street trees, leaving them completely out from street canyon designs is rarely an option. The City of Helsinki is planning to develop its current inbound motorways into city boulevards which has raised concerns towards the local air quality levels due to high projected traffic rates. The aim of this study was to find which of five street-tree scenarios, realistic for the city boulevards, is the best in terms of air quality. Pedestrian-level aerosol mass concentrations were used as the measure of air quality. Furthermore the impacts of vegetation and dependency of aerosol mass concentrations on various flow statistics were studied in order to explain the differences between the scenarios. Large-eddy simulation (LES) model PALM was utilised to study the flow field above and within a city boulevard and to model the dispersion of traffic-related aerosols. Aerosol particles of different sizes were represented using a sectional aerosol model SALSA. The suitability of the used LES setup for such intercomparison studies was also investigated. The results showed that the street trees have generally a considerable negative impact (-2% to 54%) on pedestrian-level aerosol mass concentrations. Trees were find to reduce the mean wind speeds within the street canyon, which correlated strongly with the pedestrian-level concentrations. This was particular with a parallel wind direction to the street canyon due to decreased ventilation. Turbulence produced by the street trees was partially able to compensate for the reduced ventilation in some scenarios. The increased turbulence could be observed up to heights exceeding the maximum building height. Based on the results, it is recommended to prefer variable-height street-tree canopies over uniform ones within street canyons similar to the studied one. Uneven canopy increases turbulence and related pollutant transport which partially compensates decreased ventilation due to decreased wind speeds. It is also recommendable to consider minimising the ratio of the total crown volume to the street canyon volume, as ventilation decreases sharply as the ratio increases.

Abstract Objective The objective of this thesis is to create methods to transform the most accessible digitalized version of an apartment, the floor plan, into a format that can be analyzed by statistical modeling and use the created data to find if there are any spatial or temporal effects in the geometry of apartments floor plans. Methods The first part of the thesis was created using a mix of computer vision image manipulation methods combined with text recognition. The second portion was performed using a oneway ANOVA model. Results With the computer vision portion, we were able to successfully classify a portion of the data, however, there is a lot of room for improvement due to the recognition had a lot of room for improvement. From the created data, we were able to identify some key differences concerning our parameters, location, and year of construction. The analysis however sufferers from a quite limited dataset, where few housing corporations play a large role in the final results, so it would be wise to repeat this experiment with a more comprehensive dataset for more accurate results

To understand the formation of disk galaxies it is also important to understand different feedback mechanisms that affect the formation process. Without a feedback process to delay star formation the disk galaxies should not have ongoing star formation in the present day Universe. However, this is not the case since star formation is still taking place. For example, in the Milky Way the star formation rate is still ~1 solar mass per year. Moreover, during the formation process most of the gas inside galaxies is not bound into stars. Instead when disk galaxies form inside a dark matter halo there is much more baryonic matter initially available in gaseous form than in stars. This contradicts the basic CDM model, according to which most of the gas should cool down and form stars in the absence of feedback. The goal of this thesis is to first introduce the theory behind disk galaxy formation and the feedback mechanisms affecting the galaxy formation process with the main focus being on the supernova feedback. After introducing the theory the aim is to compare how supernova feedback affects the formation of a massive Milky Way-like galaxy and a less massive dwarf galaxy using a simulation code developed by Efstathiou (2000). For both galaxies four cases are simulated. Two of them represent a basic galaxy formation model presented in this thesis. One observes a situation in which the galaxy would have a very high star formation efficiency and the second concentrates on a slightly refined model including some parameters, which are ignored in the basic model. The work conducted in this thesis proves that supernova feedback may work throughout the galaxy's lifetime and causes a significant portion of the gas to escape the galaxy. This also shows that supernova driven feedback might be a reason why disk galaxies in the present day Universe still have ongoing star formation. Also the analytic model is surprisingly realistic and produces results which not only explain why there still is star formation in the present day disk galaxies, but also why the stellar mass in disk galaxies is lower than what is predicted by the basic CDM model. In dwarf galaxies with circular speed 70 km/s the ejected gas mass may be up to 60% of the total initial gas mass and in a high star formation case the ejected gas mass may be equal to the final stellar mass. Dwarf galaxies are also more sensitive to changes in the initial parameters compared to massive galaxies. In more massive galaxies with circular speed 280 km/s the ejected gas mass is smaller, but still may be 20% of the total gas mass. Another result was that massive galaxies are not very sensitive to changes in the initial conditions and the effects of supernova feedback. Finally, in the massive galaxies gas may join a galactic fountain, which was not observed in the dwarf galaxies, in which the gas was lost.

The seas and oceans are the scene of multiple human actions, all of which cause pressures on the marine environment. Marine spatial planning (MSP) systematizes the evaluations of the spatial impacts of the human actions and take into consideration the cumulative impacts of the actions. A probabilistic model is constructed to estimate the impacts of oil shipping and offshore wind power on 16 species. The quantitative indicators of impacts are the loss of breeding success of 5 birds, the loss of the early development stages of 3 fish species and the change in the probability of presence/absence of 3 benthic species and 5 algae. The thesis model works as an independent application, but can be merged as such into an MSP tool that works with a geoinformatic system (GIS) interface. The impacts of offshore wind power and oil shipping, and especially the possible oil spill, have been studied at other marine areas, but there are only few studies about their impacts in the brackish water conditions of the Baltic Sea. The study area of this thesis is the eastern Gulf of Finland (EGOF). The model is constructed using Bayesian networks (BNs) which are graphical probabilistic models. The most important human pressures caused by the actions are identified based on literature and placed in the model accordingly. The pressures caused by operational offshore wind power are the disturbance to birds and underwater noise. The pressures caused by oil shipping are underwater noise and the oil exposure of species after a possible oil spill. The attenuation of the pressures as a function of increasing distance from the source of pressure is calculated mathematically, where possible. Expert elicitation is conducted to fill in the gaps in existing data over the subject. Altogether 6 experts were interviewed and another two were consulted informally. The different types of data are integrated in the BN, which allows quantified comparisons between different management options and alternative scenarios. The model predicts that both human actions have negative impacts on the marine environment of the EGOF. The impacts of an offshore wind mill will realize without uncertainty but they will be negligible. An oil spill, on the other hand, is unlikely to happen, but if it does, the losses will be extensive. The disturbance of the wind mill on birds extends to some hundreds of metres from the mill, depending on the bird species. The losses of the early development stages of fish caused by the underwater noise of a wind mill are nearly certainly below 20% at all distances from the mill for all studied species. With the most likely sound pressure levels of tankers, the losses to the early development stages of the fish also remain below 20% with a high level of certainty at all distances. At these tanker noise levels, the harmless noise class of <90 dB re 1µPa will be reached at some kilometres of the fairway, depending on the original noise level from a tanker. Three alternative oil shipping scenarios for 2020 were compared. The differences among the scenarios are negligible both when it comes to the impacts of underwater noise on fish and to the probability of a species to get exposed to oil. The model successfully describes the impacts of the human pressures that are known to take place, such as the impacts of offshore wind power, but requires a GIS environment and drift models to be able to predict the probabilities of an oil exposure. The applicability of the model can be increased by taking into consideration additional human actions and a wider selection of human pressures. The thesis model is a part of a MSP tool produced in TOPCONS (Transboundary tools for the spatial planning and conservation of the Gulf of Finland) project, which is a prototype of a tool that can be later applied at marine areas worldwide.

Legumes and grains are grown worldwide, with the rise of consumption the importance of identification of metabolites like phenolic compounds within them are just as essential. Phenolic compounds are secondary metabolites with multiple beneficial properties such as antimicrobial, antioxidant and anti-inflammatory. Using Py-GC/MS (pyrolysis-gas chromatography/mass spectrometry) as a faster method of identification of phenolic compounds are the basis of this investigation. A total phenolic analysis using Folin-Ciocalteu analysis has taken place to determine the presence of phenolic compounds with the eight samples – wheat, barley, oats, pigeon pea, chickpea, fava beans, green peas, and potato peels. UPLC coupled with a PDA and FLR detector will be another instrument used to determine the types of phenolic compounds present in the eight samples. Py-GC/MS was able to identify compounds with the phenol moiety but not phenolic compounds of interest. The total phenolic content analysis was able to establish that phenolic compounds were present in all eight samples. Ferulic acid, gallic acid, vanillic acid and 3,4- dihydroxyphenylacetic acid were some of the phenolic compounds identified within the eight samples, using the UPLC chromatograms and measured standards.