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Global warming is rapidly reducing the Arctic sea ice cover. Along with its major impacts in the Arctic, the sea ice loss is known to affect the climate in remote continental areas. In this thesis, the remote effects are studied by analysing data from experiments carried out using the ECHAM6 atmospheric general circulation model forced with simple sea ice concentration and sea surface temperature configurations. The European and Asian midlatitude winter responses of surface air temperature are investigated, together with anomalies of variables potentially affecting them: sea level pressure, thermal advection, adiabatic and diabatic heating and surface energy fluxes. Arctic sea ice loss was found to have contributed weakly to the European warming from the 1980s to the 2010s. With sea ice and sea surface temperature conditions projected for 2071–2100, the warming response was about 1 °C relative to the 1979–2008 climatology, despite a negative North Atlantic Oscillation phase response. In Asia, the model simulates slight cooling of about 0.5 °C east of the Urals in the past and in the eastern parts of the continent in the future. However, the cooling responses are overwhelmed by the warming effect of global forcings. The effects of internal variability are large, and the role of the thermodynamic processes and surface energy fluxes in the link between the Arctic and Eurasia is not very clear. However, the temperature responses are mostly consistent with previous research, even though the model does not capture the observed past changes well.

Lactobacillus rhamnosus GG (GG) is one of the most studied probiotics worldwide and it has proved to confer health benefits to human. However, the exact mechanism of its probiotic action is still not fully understood. Some proteins secreted by probiotics, such as p75 (Msp1) and p40 (Msp2) in GG, are reported to play an important role in gut epithelial homeostasis. The aim of this work was to develop a static biofilm plate model for analyzing exoproteomes (all secreted proteins) produced by L. rhamnosus GG biofilms. First, different culture volumes (7 mL and 10 mL), incubation times and protein precipitation methods were tested to optimize conditions in order to maximize the protein yield. Next, the impact of different sugars on the exoproteome composition of the GG cells during planktonic and biofilm mode of growth was explored. Finally, the planktonic and biofilm exoproteins were subjected to antigen profiling and protein identification. The 6-well Polystyrene Microtiter plate was used as the static biofilm model for inducing the biofilm formation of GG. Biofilms were formed for 24 h and 48 h and the protein secretion from each time point was assessed by precipitating the supernatant proteins using 10% trichloroacetic acid (TCA)/acetone or 2-D Clean Up kit (GE Healthcare). The purified proteins were subjected to one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (1-DE) and the proteins were visualized using Coomassie blue staining. 1-DE immunoblotting using antibodies raised against whole GG cells was used to analyze antigens produced by the GG biofilms under the optimized biofilm formation conditions. The antigens produced by the GG biofilm cells were compared to those produced by the GG cells during planktonic growth (from over- night cultures) and the cross-reacting proteins were visualized using an IR800-conjugated secondary antibody. The immunoblots were scanned using an Odyssey Infrared Imaging System (Licor). In addition, the impact of two different carbohydrate sources on the antigen profiles was also explored. Finally, in-liquid tryptic digestion coupled with Liquid Chromatography- tandem Mass Spectrometry analysis (LC-MS/MS) was used to identify and compare exoproteomes produced by the biofilm cells cultured in the presence of the tested carbohydrates. The results showed that the commercial 2-D Clean Up kit is better than 10% TCA protein precipitation/acetone washing, because it produced clear protein patterns with less background. However, the TCA/acetone–protocol resulted in detection of higher number of proteins in 1-DE gels. Comparative immunoblot analyses of the planktonic and biofilm exoproteins at 24 h and 48 h time points revealed a clear difference in antigen profiles between the two modes of growth. In addition, the utilized carbon source was found to have a great impact on the antigen abundances and/or export. Using LC-MS/MS, 36 exoproteins were identified from the GG biofilm cultures (identification score ≥ 40, p < 0.05). Most of the identified proteins were associated with cell wall/membrane biogenesis, peptide and sugar transporters and transcription.

This thesis aims to identify and measure labor demand and supply shocks caused by COVID-19 in Finland in 2020 and aims to replicate results from an earlier study by Brinca et al. in 2021. The method utilized is a model estimation on a Bayesian structural vector autoregression framework on quarterly data of hours worked and real wages by work sector. In order to capture the labor market dynamics in Finland within the framework, a literature review is conducted and the theory and methods are then outlined. Informative priors and literature-based parameters are established for the model, and analysis software computation is then used to and estimate the model. The model estimations show that most sectors suffered large negative supply and demand shocks in the first quarter of 2020, with significant heterogeneity between sectoral shock response. It is assessed that sectors with greater possibilities of remote work are less affected by the shocks than sectors of high-contact work. Labor supply shocks account for over 80% of the total shock effects. In the second quarter of 2020, most sectors, in turn, experienced large positive supply and demand shocks that affected the sectors with significant heterogeneity once more, with the previous quarter’s most affected sectors again experiencing the largest shocks. Labor supply shocks again accounted for around 80% of the total shock effects. The results in this thesis share a trend with the earlier study in sector heterogeneity and the shocks’ total impacts, but find an increased share in the effect of labor supply shocks on the total impact of the COVID-19 shocks.

Background: Real-life data on the role of emergency medical services (EMS) in acute heart failure (AHF) are scarce. Our aim was to describe prehospital treatment of AHF and to compare patients using EMS with self-presented, non-EMS patients. Methods: Data were collected retrospectively from three university hospitals in Helsinki metropolitan area between July 1 2012 and July 31 2013. According to the use of EMS, patients were divided into EMS and non-EMS groups. Results: The study included 873 AHF patients. One hundred were (11.5%) EMS and 773 (88.5%) non-EMS. EMS patients tended to have more comorbidities. Initial heart rate (HR) and peripheral oxygen saturation (SpO2) differed between EMS and non-EMS patients; mean HR 89.2 (SD 22.5) vs. 83.7 (21.5) /min (p=0.02) and SpO2 90.3 (8.6) vs. 92.9 (6.6)% (p=0.01). However, on presentation to ED EMS patients' vital signs were similar to non-EMS patients'. On presentation to ED 46.0% were normotensive and 68.2% "warm and wet". Thirty-four percentage of EMS patients received prehospital medication. In-hospital mortality was 6.0% and 7.1% (p=0.84) and length of stay (LOS) 7.7 (7.0) and 8.5 (7.9) days (p= 0.36) in EMS and non-EMS groups. Conclusion: The use of EMS and administration of prehospital medication was low. EMS patients had initially worse HR and SpO2 than non-EMS patients. However, EMS patients' signs improved and were similar on presentation to ED. There was no difference in in-hospital mortality and LOS. This underscores the need for equal attention to any AHF patient independent of the arrival mode.

Bakeries suffer from yearly quality problems in texture of rye bread during the first two to three months after harvest when using newly harvested rye. A cave on the top of the bread below the crust is a typical defect and so are the large holes just under the crust. Previous studies indicate that the endo-xylanase activity decreases over time in the appropriate storage conditions after harvesting. The aim of this Master’s thesis was to understand the impact of the possible difference in the endo-xylanase activity in the newly harvested rye compared to 10 weeks stored rye, on the bread texture properties. The growing conditions were exceptionally dry and hot for the grain samples in this study that might have affected the results. There were six different rye samples from four different locations in Lithuania, Estonia and Finland. The hypothesis in this study was that the decrease in the endo-xylanase activity during the first months after harvest has an impact on the rye baking functionality. The endo-xylanases in a newly harvested rye flour hydrolyze the arabinoxylans in the rye doughs more efficiently compared to the rye which is stored for 10 weeks causing the breakdown of rye bread structure. The xylanase activity, α-amylase activity, fiber content and ash content of the flour samples were analyzed. Furthermore, the texture and specific volume of the bread samples were analyzed. As expected, the xylanase activity decreased over time in the storage according to the swelling number results. There was a decrease in the endo-xylanase activity, but the decrease was not significant. Despite of the decrease in the xylanase activity over time, the sensory evaluation results did not show any significant differences in the texture of the breads baked with the fresh flour samples compared to 10 weeks stored flour samples. The crumb hardness as well as the chewiness of the breads correlated negatively with the swelling curve and endo-xylanase activity results. The breads baked with the 10 weeks stored flour samples were harder compared to the ones baked with fresh flours. There was a positive correlation between the specific volume and the swelling number results as well as between the specific volume and the endo-xylanase activity results. These results confirm that the xylanase activity decreases over time in the stored grains and the decrease in the xylanase activity results in an increase in crumb hardness and decrease in specific volume of the breads.

The European spruce bark beetle Ips typographus (L.) is a severe pest of the Norway spruce Picea abies (Karst.). The species usually attacks weakened trees, but in a consequence of a strong abiotic disturbance event, population may increase sufficiently to threaten even healthy trees. In addition to available trees for feeding and reproduction, temperature is the most important factor limiting the damage of the pest. Limiting potential of the pest’s enemies is potentially important but poorly known. There are several predator and parasite species limiting the success of I. typographus. These species are commonly known as natural enemies or natural enemy complex. Occurrences of these species are investigated in this study. Regardless of intensive studies about natural enemies, there are still remarkable gaps in knowledge. While natural enemies could theoretically be used to control pest populations, practical applications in forestry are in a very limited use. Mechanical methods, mainly sanitation and salvation loggings, are instead used to prevent outbreaks from escalating. These management practices prevent outbreak from spreading, although damage caused by loggings may also harm trees and expose these to pathogens. Possibility of using natural enemies as a part of pest control in forestry is considered in this study. Field study was conducted in SE Finland. I. typographus and natural enemy complex were sampled in 2018 by means of trapping logs settled with fixed number of I. typographus individuals. This was conducted in three different stand classes representing different gradation phases in forests to find differences between regulating potential of enemies. Stand classes were chosen based on the visible symptoms of bark beetle infestation and disturbance history. Classes were healthy (no attack), early outbreak (first symptoms and increased pest population) and declined outbreak (earlier outbreak, pest already declined near endemic level). Trapping logs with settled I. typographus were allocated to these classes, and insects emerging from trapping logs were later collected for sampling in sealed funnel traps. I. typographus population level was simultaneously monitored using pheromone traps. Differences between insect occurrences in different stand classes were statistically analysed by Kruskal-Wallis test with 0.05-level of significance for each identified enemy species and families. Spearman correlation was also used to detect any possible relations between different enemy species. Predators emerging from the logs were identified to six coleopteran families. Species were Thanasimus formicarius (Cleridae), Plegaderus vulneratus (Histeridae), Epuraea spp. (Nitidulidae), Rhizophagus spp. (Monotomidae) and from Staphylinidae Quedius plagiatus, Nudobius lentus, Phloeonomus spp., Leptusa spp. and Placusa spp. Family Elateridae was inspected as a single tested group. Predatory flies and parasitic wasps also emerged from the logs, although these were excluded from the current study. Three species had significant preference to certain outbreak classes. P. vulneratus proved most promising regulator in this study. It reproduced rapidly already during the first year of infestation. T. formicarius had significant preference for stand class, but failed to occur in sufficient numbers during the first year of infestation to have impact on the I. typographus population. Staphylids Phloeonomus spp. were very common at all stand classes but preferred healthy class. For both P. vulneratus and Phloeonomus spp. preferences for stand classes were significant, but the regulation effectiveness of these species is relatively unknown. Results suggested that limited resources in the healthy class, similar to managed forests forces both bark beetles and predators into same space, potentially increasing mortality. This result was observed by increased total numbers of beetles in the trapping logs of healthy class in comparison to outbreak classes, while simultaneously prey-predator ratio was also lower. This means that in addition to removing resources, sanitation loggings could also have increasing effect on enemy induced mortality. Small amount of deadwood potentially sustains higher endemic population of enemies, potentially increasing stands resistance to further insect induced disturbances. While some enemies were more common at the declined outbreak class, this claim was not supported by this study.

Colorectal cancer (CRC) is one of the most common types of cancers, encompassing approximately 10 % of all cancer cases worldwide. Regulation of cell proliferation and cell fate decisions is crucial for maintaining cellular homeostasis and preventing CRC initiation, a process in which the Wingless (Wnt)/β-catenin signalling pathway is known to play an important role. For instance, somatic mutations occurring in the Apc gene lead to aberrant activation of the Wnt/β-catenin pathway, which further leads to the accumulation of β-catenin into the nucleus where the TCF/LEF transcription factors, including TCF1, TCF3, TCF4, and LEF1, bind β-catenin to activate downstream Wnt target genes and promote CRC development. TCF1 is encoded by the gene Tcf7 that can be alternatively spliced to produce long (p45) and short (p33) isoforms whose function in CRC development has remained poorly understood. Previously, deletion of Tcf7 has been found to increase intestinal adenoma formation in mice with one mutated Apc allele (ApcMin/+), which are predisposed to development of multiple intestinal adenomas. To study how heterozygous deletion of the p45 isoforms affects intestinal adenoma formation and the cellular transcriptome, we have studied ApcMin/+ mice, which have a heterozygous mutation of Tcf7 gene encoding only the p33 isoform (AmTp45∆/+). In our study, we used immunohistochemistry and RT-qPCR together with a single-cell RNA sequencing (scRNA-seq) analysis. Heterozygous deletion of the p45 isoforms in the ApcMin/+ mice dramatically increased the numbers of intestinal tumours, spleen size and its white pulp areas but it had no effect on cell proliferation or expression of the Wnt-target gene Prox1 in intestinal adenomas. In addition, ApcMin/+ mice with both heterozygous p45 and Lef1 deletions developed significantly more intestinal tumours. Without the Apc mutation, neither of these mouse models developed intestinal adenomas or spleen abnormalities. RT-qPCR analysis showed decreased expression of Tcf7 in the small intestine of the AmTp45∆/+ mice. scRNA-seq analysis revealed that the AmTp45∆/+ mice downregulated various Wnt antagonists and stem cell markers and upregulated several genes that function in different metabolic pathways. Overall, these results support the concept that Tcf7 functions in synergy with Apc to repress intestinal malignancy. Our results establish a basis for comparison of the relative importance and specific functions of the TCF/LEF1 family members in CRC development.

The purpose of this study is to clarify what land use management mechanisms is used in municipalities to support wooden multistorey building and what is the impact of the land use management mechanisms in it. Finally, the objective is to conclude what explain the differences in used land use management mechanisms in municipalities to support wooden multistorey construction and the impact of the land use management mechanisms. The materials in this study were gathered in municipal websites and half structured theme interviews in two case municipalities. The results show that the two case municipalities use very different land use management mechanisms and the achieved results of supporting wooden multistorey buildings differ greatly. Great results have been gotten with formal land use management mechanisms such as zoning, but zoning only for wooden multistorey buildings contain also risks. Using only informal land use planning, such as incentives have gotten poor results, but together side by side formal and informal planning seem to achieve the best results. To conclude, the usage of what different land use management mechanisms municipalities should be using is dependent on background factors such as housing demand and attractiveness of residence milieu which reduces the risks of wooden multistorey construction, resulting that stronger support towards wooden multistorey construction can be used. In addition, better strategy, and implementation of the strategy in supporting wooden multistorey construction with land use management leads to a better result, but on the other hand the risks in wooden multistorey construction can explain the lack of success in wooden multistorey buildings and furtherly explain poor city strategy and leadership towards wooden multistorey construction.

Belt and Road initiative (BRI) has provided by the Chinese government's global infrastructure development strategy in 2013. The New Eurasian Land Bridge (NELB) is the core of the land route of BRI across Eurasia. The main purpose is to build the modern railway infrastructure lines in the Eurasian region. The thesis hypothesis NELB effectively strengthens the capacity of Russia and China for railway transport trade. It influences the further participation of China and Russia in Global Value Chains (GVCs). The study has used the Eora MRIO database on GVCs' output in China and Russia, which takes the data from 2000 to 2018 as a sample. It has combined with the World Integrated Trade Solution (WIST), World Bank and OECD database on the country's trade volume of the export sector and NELB-related indices. It has applied the combination of panel data and time series. The thesis has found that NELB contributed differently to China and Russia. In general terms of GVCs participation, NELB has absorbed Foreign direct investment (FDI) and Information and Communications Technology (ICT) input to China and Russia trade. NELB has benefited China by strengthening its soft infrastructure in financial investment. Moreover, it has benefited Russia's hard infrastructure in the railway transit stations or port establishment. In terms of bilateral trade on GVCs participation. It has conducted China's export and transport of large-scale machinery and equipment to Russia. It also has enhanced Russia's export and transport of energy materials or raw materials to China. Furthermore, NELB has shown the influence on the China and Russia's main export sectors' upgrading and governance in GVCs.

Introduction: Many studies, globally, have aimed at elucidating reasons to choose a career in dentistry. The most common motives found are reasonable working hours and aspiration to help. The aim of this study was to explore whether eventual past personal experience of orthodontic treatment and particularly the interpersonal skills of the treating orthodontist are of significance in this respect. Materials and methods: An electronic questionnaire, consisting of multiple choice and descriptive questions about dental history and experiences in dental care, was sent to dental and, as controls, psychology students within the same Faculty of Medicine, University of Helsinki, Finland. The answers between the two groups were compared and differences tested statistically. Results: The questionnaire was answered by 143 (46.0%) dental students and 94 (17.6%) psychology students. Dental students, compared to psychology students, had more positive views of their dentition and dental treatment in general (P=0.000). Among participants, 47.9% of dental students and 57.4% of psychology students had received orthodontic treatment. Of those, dental students had perceived their orthodontic treatment as less painful (P=0.001) and less uncomfortable (P=0.000) than psychology students. Moreover, dental students reported more often experiences of orthodontist taking into account their situation in life during treatment (P=0.011), and gave more positive descriptions of the orthodontist’s interpersonal skills (P=0.031). Conclusions: Dental students, compared to psychology students, had statistically significantly more positive personal experiences related to dentistry and orthodontics, supporting our hypothesis that positive experiences with orthodontic treatment likely increases the probability of choosing dentistry as the future career.