Opinnäytteet: Recent submissions

Now showing items 1-20 of 42454
  • Saarinen, Aino (Helsingin yliopisto, 2020)
    In the recent years, a decline in Finnish students’ learning outcomes has been reported in several investigations, such as in the Programme for International Student Assessment (PISA) and in the Trends in International Mathematics and Science Study (TIMSS). Further, variance in learning outcomes between students coming from different backgrounds has increased in Finland. This dissertation investigated (i) whether self-directed learning practices, use of digital learning materials at school, and participation in early education and care (ECEC) are associated with students’ learning outcomes at 15 years of age and (ii) whether these associations are modified by students’ background factors. The participants (N=5660, 5037, and 4634 in Studies I‒III) came from the Finnish PISA 2012 and 2015 datasets that constitute a representative sample of the Finnish 15-year-old students. Learning outcomes in reading, mathematical, and scientific literacy and collaborative problemsolving were evaluated with a comprehensive set of standardized tests. The frequency of learning practices (student-oriented, inquiry-based, and teacher-directed practices, and use of digital learning materials at school) were evaluated with questionnaires fulfilled by students. Participation in ECEC was evaluated with age at entry into ECEC. Background factors under investigation included gender, repetition of a grade, truancy behavior at school, family wealth, maternal education, single-parent family, and immigrant status. The data were analyzed with structural equation models that were controlled for age, gender, and parents’ socioeconomic status (the index of economic, social, cultural status). Frequent use of self-directed teaching practices or digital learning materials at school were associated with students’ weaker learning outcomes in several knowledge domains. Instead, frequenct teacher-directed practices were related to students’ higher learning outcomes. Moreover, frequent use of self-directed teaching practices or digital learning materials had more negative impact on students’ learning outcomes in students with (vs. without) risky background. Additionally, participation in ECEC before preschool was not associated with learning outcomes at 15 years of age. This association was not significantly moderated by parental socioeconomic status (as measured with the index of ESCS). At a trend level, the impact of participation in ECEC before preschool was slightly more positive for offspring of parents with high (vs. low) socioeconomic status. In conclusion, some pedagogical practices within the school system, such as frequent use of self-directed learning practices or digital learning material, were found to increase variance in learning outcomes between students coming from different backgrounds in Finland. No evidence was found that participation in ECEC would be related to learning outcomes at 15 years of age or would increase equality between students coming from different family backgrounds.
  • Arsenovich, Tatyana (Helsingin yliopisto, 2020)
    The Large Hadron Collider (LHC) accelerator at CERN will be updated into High-Luminosity Large Hadron Collider (HL-LHC) between 2025-2027, and as a result, all of the LHC experiments have to be upgraded to meet the goals set for high-quality physics data taking. Also the Compact Muon Solenoid (CMS) Tracker will undergo several planned upgrades aimed to improve the characteristics of its detectors without negative impact on physics potential. In the HL-LHC, the level of radiation will increase significantly, thus, the radiation hardness of the detectors should be improved while at the same time also improving their capability of handling the higher amounts of data. The candidate materials and technologies for the development of the detectors need to be reviewed taking the requirements of the HL-LHC data taking into account. The quality assurance of these detectors is of utmost importance to identify possible failures as soon as possible in the design phase and later during the production of the devices. The quality assurance methods should be verified to be able to reliably provide the needed characterisation parameters. In this thesis, the processing of the samples and their characterisation are described from the reliability point of view. Descriptions of processing steps, theoretical models and measurements methods are accompanied by the discussion of possible failures and suggestions how to prevent them. Special attention is put on the impact of the so-called human factor and the importance of knowledge transfer. The purpose of this work is to study the long-term stability of silicon detectors with Al2O3 thin films grown with the Atomic Layer Deposition (ALD) method and implemented as an insulation and surface passivation layer. The test samples for these studies were processed during 2011-2015 in the cleanroom facilities of the Micronova centre for Micro and Nanotechnology by Dr. E. Tuovinen. Electrical characterisation and characteristic measurements with source were performed in 2014-2018 in the Detector laboratory and cleanroom facilities of Helsinki Institute of Physics (HIP). In addition, Highly Accelerated Temperature and Humidity Stress Tests (HAST) like those performed in the HIP Detector laboratory facilities is suggested as a new approach for studies of the long-term stability of the detectors. Electrical characterisation demonstrated good long-term stability of capacitance, depletion voltage and leakage current characteristics of the test samples with Al2O3 insulation and surface passivation layer. The result of the characterisation demonstrates that samples with surface passivation are able to withstand higher bias voltage than samples without such passivation. Characteristic measurements with a Cs-137 source confirmed that the surface passivation with Al2O3 does not affect the general detector performance. Characterisation of single pixel sensors coated with the Al2O3 after the flip-chip bonding demonstrated that the additional ALD run is not harmful for the structure of the detector and does not affect its behaviour. Thus, ALD-deposited alumina coating can be recommended as a material for additional protection of silicon detector structures.
  • Vennerström, Pia (Helsingin yliopisto, 2020)
    Viral haemorrhagic septicaemia (VHS) was isolated for the first time in Finland in 2000 from a Finnish brackish water fish farm farming rainbow trout in net pens in the Province of Åland, Baltic Sea. The efforts to eradicate the disease from the Åland islands were not successful. Epidemical factors, needed for VHS management in viral haemorrhagic septicaemia virus (VHSV) positive brackish water fish farms, were studied in a 3-year project, the results of which are presented in this thesis. The study compared the ability of four different surveillance procedures and three diagnostic tests to reveal whether a fish population was infected with VHSV. The programme that was conducted as syndromic surveillance, where the farmers sent in samples for diagnostics if any signs of possible fish disease were noticed, clearly outperformed the other three programmes, which were based on active surveillance. A real-time reverse transcriptase polymerase chain reaction method proved to be at least as sensitive in detecting acute VHSV infections as virus isolation in cell culture, which is considered the gold-standard method for diagnosing VHSV. An ELISA method was used to test fish serums for antibodies against VHSV and was found to be a promising tool in VHSV eradication, particularly for screening populations during the follow-up period, before declaring an area free of infection. During the epidemics it was a common suspicion wild fish being the most likely source of the reinfections of VHSV in infected fish farms in the restriction area. Wild fish of 17 different species from VHS-positive fish farms were screened for VHSV during 2005-2008. In addition, uninfected wild perch, roach and farmed whitefish were introduced to a fish farm with rainbow trout experiencing a clinical outbreak of VHS. The wild fish did not test positive on any occasion, but whitefish were infected and started to replicate VHSV for a short time. The replication of the virus in whitefish was verified using a new qRT-PCR method that tests separately for positive- and negative-sense viral sequences in infected organ samples. The presence of VHSV in the environment on fish farms or processing plants farming or handling VHSV-positive fish was studied by testing samples for VHSV from wild blue mussels (Mytilus edulis) living in infected fish farms. Sea water and sediment from infected fish farms were also tested for VHSV. Wild uninfected blue mussels were also challenged with VHSV in two different challenge tests. Wastewater from a processing plant was tested before and after disinfection treatment. Blue mussels were not found to be carriers of VHSV on any occasion. Sea water tested positive for VHSV RNA more often during the wintertime when water temperature was close to 0°C and sunlight (UV light) sparse. Most wastewater samples collected before the disinfection treatment were positive for VHSV, but samples collected after disinfection were all negative regarding VHSV RNA. Contacts between the processing plants and the fish farms in the restriction area of VHS were very common during this study. Processing plants are usually the place where fish food and farming equipment are stored, including boats that are used for the daily servicing of the farming localities. According to the results of this study, this contact was considered a major risk for disease spread, especially during the cold part of the year when daylight is also short. Altogether, this thesis compiles the results of a series of studies targeting factors that could affect the infection pressure of VHSV.
  • Hiippala, Kaisa (Helsingin yliopisto, 2020)
    The present doctoral thesis examines the epithelial host-microbe interactions of different Gram-negative commensal bacteria in the human gastrointestinal microbiota, which consists of bacteria, viruses and eukaryotic organisms. Under steady-state conditions, commensal gut bacteria are harmless symbionts co-existing with the host as part of the normal, balanced microbiota and supporting intestinal homeostasis. On the contrary, dysbiotic microbiota with reduced species richness and altered composition is associated with many intestinal and systemic diseases. Constant communication between the microbiota and the host is enabled either by direct contact or secreted effector molecules. During the last decades, the beneficial effects of commensal bacteria on intestinal mucosa, as well as the related molecular mechanisms, have been increasingly investigated. Currently, the research focus is shifting from traditional probiotics to so-called “next-generation probiotics” and their potentially health-promoting molecules, “post-biotics”. In addition to the traditional treatment strategies for intestinal diseases, novel bacteriotherapy alternatives could be utilized to increase the presence or activity of commensal species with immunoregulatory capacity and the ability to enhance the barrier function. First, the colonic mucosal microbiota of pediatric ulcerative colitis (UC) patients was compared to non-inflammatory bowel disease (IBD) controls using colonic biopsies and pyrosequencing. Microbiota richness and diversity did not differ significantly between the UC and control subjects. Compositional microbiota changes were observed in the mucosa of UC patients with increased abundance of Firmicutes and Proteobacteria, especially the family Sutterellaceae, and decreased proportion of Bacteroidetes. Furthermore, the expression of selected host genes related to the barrier function was studied in the UC subjects. Most notably, the expressions of inflammatory cytokine interleukin-8 (IL-8), inflammation marker lipocalin-2 and calcium binding proteins, forming the IBD biomarker calprotectin, were elevated supporting previous findings in the literature. Next, the abundance and prevalence of Sutterella spp., belonging to the family Sutterellaceae that displayed increased abundance in the mucosa of UC patients, were studied using biopsies from IBD, celiac disease (CeD) and non-disease controls. In addition, epithelial interactions of the genus Sutterella were assessed in vitro. A decreasing gradient from the duodenum to the rectum was observed in the abundance of Sutterella spp. in non-disease adult subjects. No difference was detected in the prevalence of Sutterella between pediatric CeD or IBD patients and controls. Sutterella wadsworthensis was able to adhere to mucus, while Sutterella parvirubra had a higher adhesion capacity to enterocytes and showed competitiveness in adhesion against S. wadsworthensis. Sutterella spp. harbor a penta-acylated, less toxic lipopolysaccharide (LPS), which caused only a mild release of proinflammatory IL-8 from the HT-29 enterocyte cell line compared to hexa-acylated Escherichia coli. S. wadsworthensis and its LPS induced a higher IL-8 response in the HT-29 enterocytes compared to the other two species, indicating differences in their proinflammatory capacity. Overall, these findings implicated Sutterella spp. as a highly prevalent, benign gut commensal with mild proinflammatory mucosal interactions. A high-throughput screening method was developed to isolate anti-inflammatory strains from a healthy volunteer who had acted as a donor for fecal microbiota transplantation. In the screening, isolates capable of attenuating inflammation in vitro, i.e. decreasing E. coli LPS-induced IL-8 levels in enterocytes as compared to the LPS control, were considered as potentially anti-inflammatory, and identified using 16S rRNA gene sequencing and finally whole genome sequencing. The majority of the isolates eliciting anti-inflammatory activity belonged to the order Bacteroidales. In vitro epithelial interaction assays studying the Bacteroidales strains revealed no correlation between attenuation capacity and adhesion, indicating that the effect was independent of cell-cell-contact. Furthermore, the culture supernatants of attenuating isolates were also effective in decreasing the LPS induced IL-8 response in enterocytes, which supported our hypothesis concerning the presence of effector molecules. Lastly, one of the Bacteroidales strains isolated from the fecal donor was Odoribacter splanchnicus, which is known as an abundant, short-chain fatty acid producing gut commensal. Bacterial-epithelial interactions of this less studied commensal were assessed in vitro. O. splanchnicus did not adhere to enterocytes or enhance epithelial monolayer integrity, yet the bacterium and its cell-free culture supernatant displayed in vitro inflammation attenuation capacity. Furthermore, the spent medium of the O. splanchnicus strain induced a higher anti-inflammatory cytokine interleukin-10 release in relation to tumor necrosis factor alpha in peripheral blood mononuclear cells compared to O. splanchnicus cells or the E. coli control. Outer membrane vesicles (OMVs) were isolated from O. splanchnicus culture medium. The treatment of enterocyte monolayer with O. splanchnicus OMVs prior to LPS stimulation caused a significant decrease in IL-8 levels. The anti-inflammatory effect was more consistent with OMVs than bacterial cells. Taken together, O. splanchnicus seems to primarily exert beneficial interaction with the host. Commensal bacteria and intestinal gut epithelium are engaged in constant cross-talk mediated by direct cell-cell contact and/or secreted bacterial effector molecules. The delicate balance of mucosal microbiota enhancing the barrier function and keeping the intestinal immune cells alerted at an appropriate level is susceptible to disturbances potentially leading to dysbiosis. In this context, the identification of gut homeostasis promoting bacteria and their metabolites, as undertaken in this study, is a vital part of novel, personalized bacteriotherapy using a defined bacterial cocktail to assist in restoring intestinal equilibrium.
  • Tikkanen-Dolenc, Heidi (Helsingin yliopisto, 2020)
    Background: Type 1 diabetes is a chronic condition with risk of severe long-term complications (cardiovascular disease, diabetic nephropathy, neuropathy and retinopathy) that increase the risk of premature mortality, reduce quality of life and cause a huge economic burden to society. The main cause of death and inability in individuals with type 1 diabetes are cardiovascular events, and it has been shown that diabetic nephropathy is the main driver of the increased risk of cardiovascular morbidity and mortality. Diabetic retinopathy is the leading cause of vision loss and blindness in developed countries. Physical activity has been shown to improve the risk profile of individuals with type 1 diabetes. Consequently, previous cross-sectional data show that lower physical activity is associated with a higher degree of diabetic complications, but the causal relationship is unclear. Aim: The aim of this thesis is to assess how the total amount of leisure-time physical activity (LTPA) and its components of intensity, frequency and duration are associated with the development of diabetic nephropathy, cardiovascular outcomes, diabetic retinopathy and mortality in type 1 diabetes. Subjects and methods: The study subjects of this thesis are participants in the ongoing nationwide, multi-centre Finnish Diabetic Nephropathy (FinnDiane) Study. Currently, more than 5000 individuals with type 1 diabetes have been recruited and thoroughly characterized from all over Finland. LTPA was assessed at baseline by a validated self-report questionnaire. The study design is prospective and observational. Results: The intensity of LTPA was associated with the initiation and progression of diabetic nephropathy. Of the other LTPA components, frequency was also associated with the progression of diabetic nephropathy. A larger amount of total LTPA and its components were associated with lower risk of CVD events during follow-up. Only the association between LTPA frequency and incident CVD remained significant after adjustment for potential confounders. LTPA and all its components were associated with lower risk of all-cause mortality after adjusting for several confounders. However, only the LTPA intensity was associated with cardiovascular death after adjusting for covariates. Also, total LTPA and frequency of LTPA were independently associated with lower risk of mortality in individuals with type 1 diabetes and chronic kidney disease. In addition, frequent LTPA was associated with lower risk of severe diabetic retinopathy. Conclusions: Physical activity was associated with reduced risk of diabetic complications and mortality in individuals with type 1 diabetes. In addition, physical activity also seems to benefit those with diabetic complications – notably, diabetic nephropathy – and appears to be safe.
  • Peltonen, Reetta (Helsingin yliopisto, 2020)
    Background and aims Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. In Finland, 3,538 new cases were diagnosed in 2018. While the incidence of CRC is generally increasing, the mortality rates have been decreasing in many countries due to reduced risk factors, screening, and advances in pathological diagnostics, surgical techniques, and oncological treatments. Approximately half of all CRC patients develop metastatic disease, and up to 75% of the metastases are diagnosed in the liver. Contrary to many other cancers, even metastatic CRC may be treated curatively, if the metastases are limited and can be surgically removed. Currently, approximately 20–30% of the liver metastases can be resected, but over 50% of the patients develop recurrent disease afterwards. Estimating the prognosis after liver resection is of utmost importance, as identifying the patients with a high risk of recurrence enables adjusting the surgical and oncological treatments accordingly, and thus, improving postoperative survival. The aim of this thesis was to evaluate the prognostic significance of 12 biomarkers measured in serum, plasma, and tissue samples of both the primary colorectal tumors and the liver metastases in patients undergoing curative-intent liver resection for colorectal metastases. Materials and methods Altogether 442 patients who underwent liver resection for colorectal metastases at the Helsinki University Hospital between the years 1998 and 2013 were included in this thesis. The four studies are based on the serum samples from all patients (I–III), the plasma samples from a subset of 168 patients (I), and the tumor tissue specimens from a subset of 111 patients who had both primary colorectal tumors and liver metastases operated on at the Helsinki and Uusimaa Hospital District (III and IV). Serum and plasma samples were drawn before liver resection and approximately 3 months afterwards. Tissue specimens included samples of both the primary colorectal tumors and the liver metastases. The concentrations of carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and C-reactive protein (CRP) were retrieved from clinical records (I and II). Those of human chorionic gonadotropin β (hCGβ) in plasma, tumor-associated trypsin inhibitor (TATI) in plasma, and matrix metalloproteinase-8 (MMP-8) in serum were measured by time-resolved immunofluorometric assay (IFMA) methods (I and III). YKL-40 (chitinase-3-like protein-1, CHI3L1), interleukin-6 (IL-6), matrix metalloproteinase-9 (MMP-9), and myeloperoxidase (MPO) were determined in the serum samples using commercially available enzyme-linked immunosorbent assay (ELISA) kits (II and III). The expressions of matrix metalloproteinase-2 (MMP-2), MMP-8, MMP-9, and transketolase-like protein 1 (TKTL1) were analyzed in the immunohistochemically stained tumor tissue samples. Clinical data were retrieved from patient records, and information about the dates of death was obtained from the Central Statistical Office of Finland. Survival analyses were performed using the Kaplan-Meier method and the Cox proportional hazards model. Results Postoperatively elevated CEA (>5.0 µg/l) was found to predict shorter disease-free/relapse-free survival (DFS/RFS) and overall survival (OS). Preoperatively elevated CEA associated only with shorter OS (I and II). Pre- and postoperatively elevated CA19-9 (>26 or >37 kU/l) indicated shorter DFS/RFS and OS, but the additional value compared to CEA was limited (I and II). Preoperatively elevated TATI (>13 µg/l) associated with poor 3-year DFS after liver resection in the whole patient cohort, and especially in patients with synchronous liver metastases. Postoperatively elevated hCGβ (>1.0 pmol/l) associated with poor 3-year OS in the whole cohort, and it was a sign of impaired prognosis especially among male patients and those with primary rectal tumors (I). A biomarker panel comprising YKL-40, IL-6, CRP, CEA, and CA19-9 was found prognostic, as patients with 2–5 elevated biomarkers pre- or postoperatively were at an increased risk of recurrence and death after liver resection (II). High expression of MMP-9 in primary colorectal tumors and high preoperative MPO in serum indicated improved prognosis after liver resection. Additionally, the prognostic significance of these biomarkers, as well as that of MMP-2 and MMP-8, were found to depend on the clinical characteristics of the patients (III). High TKTL1 expression in the primary colorectal tumors associated with impaired prognosis after liver resection in patients with synchronous liver metastases, but with improved prognosis in those with metachronous metastases. Similar tendencies were observed concerning the expression in the liver metastases (IV). Conclusions In conclusion, CEA is a useful prognostic biomarker for most patients undergoing liver resection for colorectal metastases. However, about half of the patients do not have elevated serum levels of CEA despite of metastatic disease, and those patients may benefit from measuring other biomarkers. A biomarker panel comprising YKL-40, IL-6, CRP, CEA, and CA19-9 could be used to identify patients at a high risk of recurrence after liver resection already before the operation. MMP-9 and TKTL1 in primary colorectal tumors may serve for assessing whether the patients benefit from liver resection or need more aggressive chemotherapy, but the synchronicity of the liver metastases should be taken into consideration. Elevated preoperative serum levels of MPO indicate improved prognosis, and low levels imply a high risk of recurrence. The prognostic value of MMP-2, MMP-8, MMP-9, and MPO varies according to clinical factors, possibly due to immunological or hormonal mechanisms. The investigated biomarkers provide new information about CRC with liver metastases and increase our understanding of the disease. They help us define the prognosis after liver resection and adjust the individual patients’ treatment accordingly. Thus, they contribute to enabling the best possible care.
  • Perälampi, Heidi (Helsingin yliopisto, 2020)
    Tavoitteet Talous ja syntyvyys ovat molemmat laajalti tutkittuja alueita, ja näiden kahden välinen yhteys on hyvin todennettu. Tutkimusta, jossa talouden tulkittaisiin vaikuttavan syntyvyyteen elämän kulun kautta on kuitenkin paljon vähemmän. Tämän tutkimuksen ensimmäinen tavoite on tutkia, oliko 90-luvun lamalla vaikutus silloisiin suomalaisiin lapsiin. Hypoteesina on, että jos perheen taloudellinen tilanne heikkeni 90-luvun laman aikaan, ovat silloiset lapset vähemmän halukkaita hankkimaan myöhemmin aikuisuudessa omia lapsia. Toinen tavoite on selvittää, muuttuuko tämä yhteys, riippuen lapsen iästä perheen taloudellisten ongelmien aikana. Metodit Tutkimuksen koehenkilöt valittiin FinnFamily-rekisteriaineistosta, joka koostuu 60 000 suomalaisen perheen seuraamisesta jo neljän sukupolven ajan. 43 432 vuosina 1975-1989 syntynyttä koehenkilöä valittiin FinnFamily-aineistosta tähän tutkimukseen.Koehenkilöitä ja heidän vanhempiaan seurattiin vuoden 2012 loppuun asti. Analyysit tehtiin käyttämällä Coxin regressiota. Koska monet koehenkilöt tulivat samoista perheistä, robustia kovarianssimatriisi-menetelmää käytettiin sallimaan korrelaatio perheenjäsenten kesken. Tulokset ja johtopäätökset Vanhempien taloudellisen tilanteen muutos 90-luvun laman aikaan ei laskenut lapsen todennäköisyyttä saada oma lapsi tulevaisuudessa. Myöskään interaktiosta vanhempien taloudellisen tilanteen muutoksen ja lapsen iän välillä ei saatu näyttöä. Sen sijaan saatiin hypoteesien vastainen tulos, jonka mukaan vanhempien 90-luvun laman aikainen tulojen lasku ja huomattava nousu nostivat lapsen todennäköisyyttä saada myöhemmin oma lapsi. Tulojen laskun osalta tulos säilyi, kun kontrolloitiin koulutustaso, sukupuoli, ikäkohortti ja sisarusten määrä. Laman aikainen tulojen nousu ei ollut tilastollisesti merkitsevästi yhteydessä myöhempään korkeampaan todennäköisyyteen saada lapsi, kun sisarusten määrä kontrolloitiin. Tulos oli odottomaton, ja lisää tutkimusta tarvitaan selventämään syitä ilmiön taustalla. Erityisesti pitkittäistutkimusta, jossa mitattaisiin myös koehenkilöiden subjektiivisia kokemuksia ja narratiiveja vanhempien taloudellisista haasteista tarvitaan jatkossa.
  • Kiikeri, Mika (Helsingin yliopisto, 2020)
    The evaluation of arguments has not previously been approached from the perspective of cognitive factors that mirror decision-making in real time. This study examined how the reinforcement of intuitive and analytical thinking affects the identification of argumentation errors and the difficulty of choice manifested by evaluators in conflict situations. The results were partly in line with the assumptions: argumentation errors were identified in the context of analytical thinking more efficiently than in the context of intuitive thinking. In part, the results were contrary to assumptions. The effect of strengthening analytical thinking was smaller than expected and was possibly influenced by subjects' expectations of the experimental situation. The reinforcement of intuitive thinking, in turn, led to a seemingly contradictory result, as the difficulty of decision-making seemed to either increase or decrease depending on the evaluation method. Indeed, the results provided support for the view that the time spent by individuals to respond reflects uncertainty in response, whereas moving the mouse reflects the difficulty of decision in a conflicting situation as well as the difficulty of the tasks. The results suggest that the evaluation of arguments can be rapid and relatively certain, even if it simultaneously includes ambivalent features that increase decisional conflict.
  • Närvänen, Eija (Helsingin yliopisto, 2020)
    Objective. The FRIENDS programme is a group cognitive behavioural therapy (CBT) programme, developed for the prevention and treatment of child and adolescent anxiety and depression. In the context of prevention, FRIENDS has been extensively researched; however, little research has been conducted on FRIENDS in a treatment setting and with different populations. To help fill this gap, the aim of the present study was to evaluate the effectiveness of the Finnish version of FRIENDS in reducing internalising symptoms in children diagnosed with psychiatric and neuropsychiatric disorders. Methods. The present study was conducted at Helsinki University Hospital (HUS) Child Psychiatry outpatient clinics in the Helsinki metropolitan area, Finland. The participating children (n = 99, mean age = 9.45 years, range 6–13 years, 68.7 % boys) were randomly assigned to either FRIENDS (n = 52) or a waitlist control group (n = 47), which received treatment as usual for a period of 3 months before the intervention. The children’s internalising symptoms were assessed using parent- and teacher-report questionnaires (Child Behavior Checklist and Teacher’s Report Form) at referral to treatment, pre-treatment, post-treatment, and six-month follow-up. Results and conclusions. In both groups, there was a medium-sized statistically significant decrease in parent-reported internalising symptoms immediately after the intervention; however, these improvements were not retained at six-month follow-up. Teacher-reported internalising symptoms followed a similar pattern of decrease during the intervention and increase during follow-up; however, these changes were smaller in magnitude and did not reach statistical significance, possibly due to loss of statistical power caused by missing data. Neither parent- or teacher-reports showed an intervention effect, with children’s internalising symptoms exhibiting similar changes regardless of whether they belonged to the intervention group or the waitlist control group, which received treatment as usual during the wait period. These results raise questions on the durability of treatment effects and the superiority of FRIENDS over active waitlist control conditions or treatment as usual when treating children diagnosed with diverse psychiatric and neuropsychiatric disorders in a community setting where treatment adherence and integrity may not be ideal.
  • Rai, Neha (Helsingin yliopisto, 2020)
    Solar UV-B radiation (290–315 nm), UV-A radiation (315–400 nm), and blue light (400–500 nm) regulate multiple aspects of plant growth and development, and these are mediated by different photoreceptors. In plants, UVR8 is described as a UV-B photoreceptor, while cryptochromes (CRYs) are described as UV-A/blue photoreceptors, based on their absorption maxima and action spectra. However, these photoreceptors are also sensitive to other wavelengths outside the wavelengths of maximum absorption. Based on this property, their roles could differ in full-spectrum sunlight than those reported from experiments performed in controlled environments. In sunlight, both UV-B and UV-A/blue photoreceptors are simultaneously activated, and there is a possibility that their signaling pathways interact. However, an interaction between UVR8 and CRYs regulating transcriptome-wide responses remained unexplored. Furthermore, persistent high solar irradiance is often followed by drought in the field, and studies have indicated that UV and drought interact to regulate plant physiological responses. However, an interaction for metabolic and transcript abundance responses has not been well-described. These gaps in knowledge are addressed in my thesis through three main aims: (1) to identify the individual roles of UVR8 and CRYs in the perception of solar UV-B, short-wave UV-A (315–350 nm, UV-Asw), long-wave UV-A (350–400 nm, UV-Alw) radiation, and blue light by plants, (2) to test the interaction between UVR8 and CRYs under solar UV radiation, and (3) to determine if pre-exposure to solar UV radiation could provide acclimation to subsequent drought stress in plants. To achieve the first two aims, I used Arabidopsis thaliana wild type and mutants impaired in UVR8 and CRYs photoreceptors and exposed them to different ranges of wavelengths of solar or simulated solar UV radiation and blue light under optical filters. To achieve the third aim, I used two accessions of Medicago truncatula (Jemalong A17 and F83005-5). I exposed them to solar UV radiation using optical filters and subjected them to drought stress by restricting watering in a factorial experiment. The results indicated that UVR8 mediates the perception of both UV-B and UV-Asw radiation. In contrast, CRYs mediate the perception of UV-Alw radiation and blue light. A further novel finding is that UVR8 and CRYs interact antagonistically to regulate transcriptome-wide responses under UV-B and UV-Asw radiation. My thesis also provides evidence that UV-B+UV-Asw radiation and mild drought can interact positively to trigger acclimation through an increase in epidermal UV screening in the drought-intolerant accession, F83005-5, and through an increase in transcript abundance of CHALCONE SYNTHASE in the moderately drought-tolerant accession, Jemalong A17. Furthermore, all three studies showed a distinct response to solar or simulated solar UV-B+UV-Asw and UV-Alw radiation, suggesting a need to split UV-A into short and long wavelengths for future studies on UV-A radiation.
  • Nissilä, Juho-Jooel; Savelieva, Kateryna; Ung-Lanki, Sari; Lampi, Jussi; Elovainio, Marko; Pekkanen, Juha (Helsingin yliopisto, 2020)
    Koulun huono sisäilman laatu on yhteydessä oppilaan raportoimiin oireisiin. Tässä tutkimuksessa selvitimme, vaikuttaako vanhempien raportoima huoli lasten koulun sisäilman laadusta koulun todetun sisäilmaongelman ja oireiden lisääntyneen raportoinnin väliseen yhteyteen. Tutkimuksessa käytetty tietokanta kerättiin viidestä suomalaisesta alakoulusta, joissa oli todettu sisäilmaongelma ja viidestä kontrollikoulusta. Oppilaiden vanhemmat (n = 1868) raportoivat kyselyyn vastaamalla kokemansa huolestuneisuuden asteen sisäilman laatuun liittyen. Lisäksi vanhemmat raportoivat lastensa kokemat oireet. Todettujen sisäilmaongelmien, huolen ja viiden oiresumman (hengitystie-, alahengitystie-, silmä-, iho- ja yleisoireet) välisiä assosiaatioita tutkittiin logistisella regressioanalyysilla ja mediaatioanalyysilla. Vanhemmat olivat keskimäärin huolestuneempia kouluissa, joissa oli todettu sisäilmaongelma. Todetut sisäilmaongelmat olivat vahvassa yhteydessä huolestuneisuuden ja kaikkien tutkittujen oiresummien kanssa. Vanhempien huolestuneisuus oli yhteydessä kaikkien tutkittujen oiresummien kanssa. Mediaatioanalyysin tulosten perusteella näyttäisi siltä, että vanhempien huolestuneisuus saattaa selittää valtaosan todetun sisäilmaongelman ja oireraportoinnin välisestä yhteydestä. Jatkotutkimuksia tarvitaan kuitenkin kausaalisten suhteiden tarkemmaksi hahmottamiseksi todettujen sisäilmaongelmien, huolestuneisuuden ja oireraportoinnin välillä. Vanhempien huolestuneisuus saattaa olla keskeinen osa joidenkin suomalaisten koulujen sisäilmaongelmia. Sisäilmakyselyt ovat tärkeä informaationlähde, mutta niiden tuottamien tuloksien tulkinta tulee tehdä varoen, kun vastaajien keskuudessa tiedetään olevan merkittävää huolestuneisuutta. Päätökset rakennusten korjaustöiden aloittamisesta tulee tehdä asiamukaisiin rakennusteknisiin tarkastuksiin perustuen.
  • Välkki, Kristina (Helsingin yliopisto, 2020)
    Suusyöpäleikkauksen jälkeinen infektio hidastaa potilaan paranemista, pitkittää sairaalassaoloaikaa, heikentää potilaan ennustetta ja voi viivästyttää liitännäishoitojen aloittamista. Tämän tutkielman tarkoituksena oli perehtyä suusyöpäpotilaan hoitopolkuun, leikkauksen jälkeiseen infektioriskiin, ja kerätyn tutkimusaineiston perusteella selvittää, kuinka monelle suusyöpäpotilaalle tuli infektio leikkaushoidon jälkeisten ensimmäisten kolmen kuukauden aikana. Tutkimusaineistosta selvitettiin, minkälaisia infektioita suusyöpäpotilailla todetaan leikkauksen jälkeen, ja pyrittiin tunnistamaan infektioiden riskitekijöitä. Erityisesti tarkoituksena oli tutkia infektioiden yhteyttä sairaalassaoloaikaan ja mahdolliseen tehohoitojaksoon. Kyseessä oli retrospektiivinen tutkimus, jonka kohteena olivat HYKS Suu- ja leukasairauksien klinikalla vuosina 2016-2017 primäärikasvaimen vuoksi hoidon arviossa olleet suusyöpäpotilaat. Tutkimuksen tulosmuuttujana oli leikkauksen jälkeinen infektio. Tutkimusaineisto koostui 98:sta suusyöpäpotilaasta, joista 85 potilasta täyttivät aineistolle asetetut kriteerit. Leikkauksen jälkeinen infektio kehittyi 11:lle potilaalle (12,9%), joista kahdelle potilaalle kehittyi kaksi erillistä infektiofokusta. Tavallisimpia leikkauksen jälkeisiä infektioita olivat keuhkokuume ja leikkausalueen infektio suussa. Korkea ikä, yleissairastavuus, pitkälle edennyt syöpäsairaus, sekä leikkaushoidon osalta trakeostomia, kauladissektio ja mikrovaskulaarisiirteen käyttö olivat yhteydessä leikkauksen jälkeisten infektioiden korkeampaan ilmaantuvuuteen. Infektiopotilailla oli pidempi tehohoitojakso ja sairaalassaoloaika. Leikkauksen jälkeisten infektioiden ehkäisemiseen ja varhaiseen toteamiseen on kiinnitettävä jatkossa yhä enemmän huomiota. Tämän tutkimuksen tuloksia voidaan hyödyntää HUS-potilaiden hoidon suunnittelun kehittämisessä sekä yhtenäisten hoitosuositusten laatimisessa. Jatkotutkimuksia tarvitaan suusyöpäpotilaan leikkauksen jälkeisten infektioiden riskitekijöiden tunnistamiseksi entistä tarkemmin sekä tehokkaiden hoitokäytäntöjen optimoimiseksi.
  • ROTO, SUOMA (Helsingin yliopisto, 2020)
    Syntymäasfyksia on tila, jossa sikiö tai syntyvä lapsi kärsii hypoksemian lisäksi hiilidioksidiretentiosta ja asidoosista. Se voi johtaa aivotoiminnan häiriöön eli hypoksis-iskeemiseen enkefalopatiaan (HIE), jonka hoitona käytetään vastasyntyneen ruumiinlämmön alentamista 33 asteeseen kolmen päivän ajaksi. Vaikea-asteisessa HIE:ssa mortaliteetti on korkea, ja henkiin jääville lapsille kehittyy usein pysyviä neurologisia vammoja. Asfyksialle altistavia äidin sairauksia sekä raskauden ja synnytyksen aikaisia riskitekijöitä tunnetaan monia, ja toisaalta suuri osa asfyksiatilanteista tulee yllättäen eikä ole ennakoitavissa. Tämän tutkimuksen tavoitteena oli kartoittaa erityisesti ammattilaisten toiminnalla vältettävissä olevia riskitekijöitä, jotka ovat johtaneet keskivaikeaan ja vaikeaan vastasyntyneen HIE:aan ja vaatineet viilennyshoitoa. Tutkimus toteutettiin retrospektiivisenä tapaus-verrokkitutkimuksena vuosina 2013 – 2017 Helsingin yliopistollisen sairaalan synnytyssairaaloissa synnyttäneille äideille. Jokaista 88:aa viilennyshoidettua vastasyntynyttä kohden valittiin samaa sukupuolta oleva, samassa sairaalassa ja samalla menetelmällä seuraavaksi syntynyt lapsi. Tiedot äitien terveydentilasta, raskaudesta ja synnytyksestä kerättiin sairaalan potilastietojärjestelmästä. Riskitekijöiden assosiaatiota HIE:n kehittymiseen arvioitiin logistisella regressioanalyysillä. Kaikista kirjallisuuden perusteella valituista todennäköisistä riskitekijöistä monimuuttuja-analyysiin valikoitiin muuttujat, joiden OR yksimuuttuja-analyysissä oli tilastollisesti merkitsevä. Synnytyksen käynnistäminen (aOR 3.08), äidin tupakointi (aOR 1.45) ja obstetriset hätätilanteet (aOR 3.51), osoittautuivat HIE:n itsenäisiksi riskitekijöiksi. Tutkimusryhmän käynnistetyissä synnytyksissä oli enemmän alatiesynnytyksiä kontrolliryhmään verrattuna (p=0.03). Tutkimustulosten perusteella päivystyskeisarileikkausta tulisi harkita aiempaa herkemmin käynnistettyihin synnytyksiin liittyvissä komplikaatioepäilyissä. Jatkossa tutkimuksia kannattanee suunnata erityisesti sikiön hyvinvoinnin seurannassa käytettävien menetelmien kehittämiseen.
  • Huovinen, Antti (Helsingin yliopisto, 2020)
    Tausta: Traumaattisen aksonaalisen vaurion (TAI) merkitystä prognostisena tekijänä lievässä traumaattisessa aivovammassa ei ole tutkittu tarpeeksi. Yksittäisiä tutkimuksia löytyy TAI:n merkityksestä oireisuuteen ja kokonaisvaltaiseen toipumiseen lievän aivovamman jälkeen, mutta kirjallisuudessa ei löydy viitteitä, jotka suoraan tutkisivat lievillä aivovammapotilailla TAI-leesioiden vaikutusta työhönpaluuseen Tavoitteet: Tavoitteena on tutkia, mikä on traumaattisen aksonaalisen vaurion prognostinen merkitys työhönpaluuseen, posttraumaattisiin persistoiviin oireisiin sekä kokonaisvaltaiseen toipumiseen lievän traumaattisen aivovamman jälkeen. Metodit: Tutkimus sisälsi 113 prospektiivisesti kerättyä lievän aivovamman saanutta työikäistä ja työssäkäyvää potilasta. Akuuttivaiheen jälkeen potilaat lähetettiin HUS Aivovammapoliklinikalle neurologin arvioon noin kuukauden kuluessa tapaturmasta. Tätä edeltävästi potilaat kävivät 3T MRI-tutkimuksessa 3-17 vuorokauden sisällä vammasta. HUS Aivovammapoliklinikalla arvioitiin myös oireisuus Rivermead Post-Concussion Symptom Questionnaire -kyselyllä (RPQ) ja kokonaisvaltainen toipuminen Glasgow Outcome Scale Extended -mittarin (GOS-E) avulla. Työhönpaluu arvioitiin retrospektiivisesti jatkuvana muuttujana ja onnistunut työhönpaluu varmistettiin strukturoidulla puhelinhaastattelulla. Tulokset: 98,2% aivovammapotilaista oli palannut työelämään vuoden kohdalla. Työhönpaluuajan mediaani oli 9 vuorokautta. TAI-potilaat (n=22) eivät tilastollisesti eronneet muista lievän aivovamman saaneista potilaista oireisuuden suhteen, ja heidän kokonaisvaltainen toipuminen oli yhtä hyvää. Työhönpaluuajoissa ei ollut tilastollisesti merkittävää eroa ryhmien välillä. Pohdinta ja johtopäätökset: Tutkimuksessa TAI-potilaat toipuivat yhtä hyvin kuin muut lievän aivovamman saaneet potilaat. Traumaattinen aksonaalinen vaurio ei välttämättä ole prognostinen tekijä työhönpaluulle lievässä aivovammassa. Sen sijaan, että tavoittelisimme yhä tarkempia kuvantamismenetelmiä, jatkossa syytä olisi keskittyä muihin riskitekijöihin sekä suojaaviin tekijöihin, jotka vaikuttavat lievästä aivovammasta toipumiseen.
  • Hiltunen, Jesse (Helsingin yliopisto, 2020)
    Pään ja kaulan alueen karsinoomat ovat ominaisuuksiltaan vaihteleva joukko pahanlaatuisia kasvaimia, jotka tyypillisesti leviävät kaulan imusolmukkeisiin. Näiden syöpien hoito on kirurgia, johon yhdistetään säde- ja lääkehoito, jos epäillään syövän levinneen. Tutkijat kehittävät jatkuvasti lääkkeitä, ja tässä keskeisessä roolissa on yksilöllinen lääketestaus potilaista otetuilla syöpäkudosnäytteillä. Fragmenttikasvatuksessa potilaasta kerätty kudosnäyte käsitellään pienemmiksi kudospaloiksi eli fragmenteiksi, joita voidaan laboratorio-olosuhteissa kasvattaa ja tutkia. Tämän tutkimuksen tavoitteena oli kehittää fragmenttikasvatusta syöpänäytteiden tutkimusmenetelmänä sekä selvittää kahden eri kasvatusmatriisin potentiaalia syöpänäytteiden kasvatuksessa ja lopulta lääketestauksessa. Tavoitteena oli systemaattisesti tutkia potilailta kerätyt syöpänäytteet ja vertailla kahta kasvatusmatriisia keskenään. Kasvatuksista analysoitiin sekä makro- että mikroskooppisia ominaisuuksia eri aikapisteissä. Analyysissa värjättiin useita erilaisia proteiinimerkkiaineita, joiden on todettu ilmentyvän pään ja kaulan alueen karsinoomissa. Ki67 on solukierron mitoosiin liittyvä proteiinimerkkiaine, jota käytettiin osoittamaan kasvatuksissa tapahtuvaa solujakautumista. BMI-1 puolestaan on sikiökauden soluissa ilmenevä proteiini, jonka on kuvattu ilmenevän myös suusyövissä. TUNEL-entsyymivärjäyksellä pyrittiin näyttämään solukuoleman määrää ja sijaintia. Kasvatusten käsittely- ja värjäysprotokollat kehittyivät merkittävästi jo tutkimuksen aikana. Lisäksi värjäystuloksista saatiin mielenkiintoisia viitteitä kasvatusmatriisien ominaisuuksista. Keskeisimmät tulokset olivat BMI-1-positiivisten solujen löytyminen fragmenttikasvatuksista, sekä solukuoleman ja –jakautumisen samankaltaisuus kasvatuksissa ja alkuperäisessä syöpäkudoksessa. Tutkimuksessa verrattiin myös kudoksensäilöntäliuoksessa yön yli säilöttyä syöpäkudosnäytettä välittömästi analysoituun näytteeseen, ja alustavien tulosten mukaan ensin mainitussa kuolevien solujen osuus oli merkittävästi suurempi.
  • Kervinen, Kaarlo; Lähdeoja, Tuomas; Salmela, Mikko; Paavola, Mika (Helsingin yliopisto, 2020)
    Retrospektiivisen tutkimuksen tavoitteena on selvittää HUS Töölön Sairaalassa vuosina 2007-2016 lukkolevyosteosynteesillä hoidettujen olkaluun alaosan nivelpintaan ulottuvien murtumien (AO-C-tyyppi) lyhyen ja keskipitkän aikavälin toiminnallisia ja radiologisia tuloksia. Samalla saadaan tietoa epätyydyttävää tulosta ennustavista tekijöistä ja voidaan verrata tuloksia kyynärtekonivelaineistoihin. Olkaluun alaosan nivelen sisäinen murtuma johtaa hoitamattomana huonon toimintakyvyn tarjoavaan kyynärpähän. Nuorilla hoitolinja on rutiininomaisesti operatiivinen, avoreduktio ja osteosynteesi kyynärnivelen toiminnan palauttamiseksi. Vanhuksilla osteosynteesi on teknisesti haastavaa murtumien mittavammasta pirstaleisuudesta johtuen sekä murtuman kiinnityksen pettämisiä, luutumattomuutta ja jäykkyyttä ajatellaan esiintyvän enemmän kuin työikäisillä. Kyynärnivelen tekoniveltä on tarjottu ratkaisuksi vanhusten murtumien hoidossa. Töölön sairaalan suuri volyymi tarjoaa myös kansainvälisesti merkittävän kokoisen potilasmateriaalin. Tutkimukseen pyydetään kaikkia 1.1.2007- 30.6.2016 Töölön sairaalassa olkaluun alaosan C-tyypin murtuman vuoksi leikkauksella hoidettuja murtuman syntyhetkellä yli 65-vuotiaita potilaita. Alkuajankohta on valittu siten, että lukkolevyt ovat siihen mennessä vakiinnuttaneet asemansa rutiinihoitona. Soveltuvat potilaat kutsutaan tutkimuskäynnille, jonka yhteydessä yläraajojen toimintakyky tutkitaan kliinisesti sekä vastataan toimintakykymittareiden kysymyksiin. Tutkimuksen päätulosmuuttuja on Oxford Elbox Score (OES) –mittari, joka määrittää kyselylomakkeen avulla kyynärnivelen toimintakyvyn vaikutusta arkielämään. Toissijaisina tulosmuuttujina ovat Mayo Elbow Performance Score (MEPS) –mittari, quick-DASH, kyynärnivelen kliinisesti määritetty toimintakyky ja potilaan subjektiivinen tyytyväisyys kyynärpään toimintaan. Lisäksi otetaan kyynärnivelen rtg-kuvat radiologisten muutosten selvittämiseksi. Potilailta määritetään myös terveen puolen toimintakyky, jolloin kunkin terve puoli toimii vertailuryhmänä. Seuranta-aika tulee olemaan vähintään yksi vuosi vammasta, suurimmillaan noin 8,5 vuotta. Keskeisiä taustatietoja ovat vammamekanismi, murtuman luokka ja vammaan sekä leikkaushoitoon liittyvät komplikaatiot. Tutkimus julkaistaan kyseisen erikoisalan kansainvälisessä lääketieteen lehdessä. Tutkimuksen tuloksia voidaan hyödyntää määrittämään HUS Töölön sairaalassa käytössä olevia hoitolinjoja kyseisen vammatyypin osalta.
  • Malassu, Irina (Helsingin yliopisto, 2020)
    HUS, suu- ja leukasairauksien klinikassa (SLK), Pää- ja kaulakeskuksessa tehdään vuosittain 70–80 ortognaattis-kirurgista leukojen leikkausta aikuisille, joilla on vaikea purentavirhe ja siihen liittyvä vertikaalinen, transversaalinen ja/tai antero-posteriorinen leukojen epäsuhta sekä purennasta aiheutuvaa vakavaa terveydellistä haittaa. Ortognaattis-kirurgista hoitoa voivat tarvita myös potilaat, joiden purenta on muuttunut kasvojen alueen murtuman seurauksena. Ortodonttis-kirurginen hoito on potilaalle raskas sekä fyysisesti että psyykkisesti. Hoito on pitkäkestoinen, vaatii sairaalahoitoa ja potilaan ulkonäössä voi tapahtua suuriakin muutoksia. Siksi hoitoa ennen on selvitettävä ja arvioitava potilaan psykososiaalinen tilanne, leikkauksen hyödyt ja siitä mahdollisesti aiheutuvat haitat sekä potilaan odotusten realistisuus. Tutkimuksemme tavoitteena on selvittää ortognaattis-kirurgisten potilaiden hoidon kulku; perehtyä siihen sekä kirjallisuuden, kliinisen toiminnan sekä ortognaattis-kirurgisen potilaan haastattelun kautta; oppia ymmärtämään ortognaattis-kirurgisen hoidon suunnittelu, hoidon toteutus sekä ongelmat ja hyödyt. Tässä työssä keskitytään erityisesti tapaturmapotilaaseen ja surgery first-tyyppiseen hoitoon. Kliinisenä materiaalina on HUS:n Pää-ja kaulakeskuksessa, Suu- ja leukasairauksien klinikassa keväällä 2019 leikattu potilas. Potilastapauksemme osoittaa, että ortognaattista kirurgiaa voidaan toteuttaa myös potilaille, joiden elämäntilanne on syystä tai toisesta haastava. Päihdetaustaa omaavilla henkilöillä voi esiintyä anestesian sekä postoperatiivisen kivunhallinnan ongelmia. Tällaisissa tapauksissa on mietittävä erityisen tarkasti etukäteen, millaisia haasteita voi tulla vastaan ja miten ne ratkaistaan. Hoitoprosessin aikana huomioitavaa on potilaan informointi vertaistukiryhmistä sekä niihin ohjaaminen tarvittaessa. Myös hoitohenkilökunnan tavoitettavuus sekä potilaalle tarjoama henkinen tuki on välttämätöntä.
  • Liu, Haiqin (Helsingin yliopisto, 2020)
    During the past decade, the demographic changes brought about by international mobility have diversified education in Finland. One type of diversification is the increasing number of teachers of immigrant background. However, how immigrant teachers experience the Finnish educational system has not yet been amongst the topics of full-scale academic research (Nishimura-Sahi, Wallin & Eskola, 2017). There is an emerging need to address this research gap by giving voice to immigrant teachers who are rarely heard. This doctoral thesis sets out to investigate the experiences and perceptions of immigrant teachers working in Finland, taking Chinese immigrant teachers of the Chinese language as a case study. The findings of this PhD study are presented in the form of three academic publications and an extended summary. The first article looks into the social discourses on Finnish education in general and Chinese language education in particular, that could potentially influence immigrant Chinese teachers’ presumptions and expectations about being a Chinese language teacher in Finland. The first article forms the background of the doctoral study. The second article and the third article examine the intercultural experiences and the perceptions of Chinese immigrant teachers in Finland. The second article reveals the multiple facets of immigrant teachers’ experiences which are connected to how the teachers perceive their positions in Finland. The third article examines the teachers’ cross-national comparisons on Chinese language education, which also reveal how the teachers perceive their positions in comparison with colleagues working in another context. The findings in all of the three publications suggest a strong link between experiences, perceptions and intercultural imaginations, as well as constructed discourses. The findings of this doctoral study lead to both theoretical and practical implications. Theoretically, a new model for understanding the experiences of immigrant teachers was developed. This model takes into account the multiple facets of immigrant teachers’ experiences, the power relations in the context under review and their influence on intercultural imagination and discourses. Practically, the findings suggested that 1) stakeholders should listen to the needs and concerns of immigrant teachers and provide equal treatment to all kinds of teachers; 2) regular continued professional development training plays a very important role in helping teachers to update their subject knowledge and teaching skills, but also in providing opportunities for all types of teachers to learn together; 3) intercultural teacher education and training should also help the teachers to become aware of the ongoing discourses, and reflect critically on their own cultural assumptions.
  • Maaperä, Ilona (Helsingin yliopisto, 2020)
    CONSENT, ENGAGEMENT AND THE SENSE OF COMMUNITY The Educational Activities of The Settlement Movement in Helsinki 1920–1939 This doctoral dissertation focuses on the educational activities of the Finnish Settlement Movement in Kalliola Settlement in Helsinki between 1920 and 1939. Kalliola Civic Institute, a part of the settlement, concentrated in educating the working class living in Helsinki. The theoretical base of this thesis relies on the concepts of consent and engagement. I study how consent was created and maintained. I study the work of Kalliola Settlement and especially the work of its civic institute and the clubs for children and youngsters. I look at the whole process of governing, with a special interest in the role of Christian faith in the work and as the motivator of the work. This study is based on data preserved in Helsinki City Archives: action reports, registration forms, minutes of meetings, diaries, instructions and financial details. In the settlement the governing was constructed by personal interaction and the sense of community. In building up this community and its governing system the settlement used many methods: indoctrination for the younger ones, softer influencing for the adults. The settlement had a large number of regular meetings, which helped to control all the activities of the settlement. The sense of community was enhanced in many ways. An individual could spend almost all his or her leisure time in the settlement. An important feature was the students’ union, which arranged regular parties and meetings. There were a lot of religious activities to attend. The participants had a total freedom of choice. One did not have to be a member of the organization – as a result it was probably easier for a worker to try for example religious activities as there was no coercion of doing that. The activities of the settlement movement differed from other organizations doing the same. The work of the settlement comprised all ages of man, from children to adults. There were Sunday schools and clubs for children, educational courses for adults, an organization inside the settlement doing social work and a wide variety of options for spending one´s leisure time. All these were important for the totality of the settlement. The civic institute offered education, but it was also an important passage to the other functions of the settlement. Other similar institutes called workers' institutes emphasized a scientific base for their teaching. The settlement wanted to offer an option which took into account even the spiritual, religious needs of its students. The founders of the settlement had a religious conviction for their work. The work of the settlement was supported by society. The most important financiers were industrial companies, who willingly supported work whose aim was to ensure the peaceful development of society in the difficult situation after the civil war. The church financed the settlement, because it was interested in maintaining its role in the lives of the workers. The civic institute also had a role for the financing, it got state aid. The governing system worked well in the beginning. Gradually the workers disappeared and were substituted by middle class women doing office work. In this process the hold of the settlement started to loosen, the students were no longer willing to comply with the system and spend their whole leisure time in the settlement.
  • Niemi, Justiina (Helsingin yliopisto, 2020)
    Propionibacterium freudenreichii is a dairy propionic acid bacterium and it is used as adjunct culture in Swiss-type cheese manufacture. The bacterial strain is known for its GRAS (Generally Recognized as Safe) status, and it is safe to use in food. Based on previous studies, P. freudenreichii requires anaerobic conditions to start bacterial growth. Bacterial viruses ‘bacteriophages’ uses two life cycles, lysogenic or lytic cycle. The life cycle of bacteriophages affects bacterial cell lysis or division. Researchers are interested in fortifying foods naturally with vitamin B12. P. freudenreichii is known for its ability to actively produce vitamin B12. This master's thesis aims were to study 1) The effect of oxygen contentration on Propionibacterium freudenreichii subsp. freudenreichii JS7 strain and 2) the effect of oxygen consentration on the prevalence of bacteriophage in P. freudenreichii JS7 strain. In this study, P. freudenreichii JS7 strain was grown at different oxygen concentrations. Bacterial growth was observed by cell density measurements and cell plating. In the preliminary experiment, the strain was grown 1) anaerobically 2) two stages which includes aerobic and anaerobic growth conditions and 3) aerobically. Based on the partial results of the preliminary experiment, the fermentation was performed in a bioreactor in an anaerobic growth condition. The cell plating results of the bioreactor experiment were used to study the effect of oxygen concentration on the presence of bacteriophage in a bacterial strain by using three primer pairs. The polymerase chain reaction was applied to study the presence of the bacteriophage genome as a plasmid, free, and prophage which means that phage genome is integrated into the bacterial chromosome. Based on the results of this study, the cell density of P. freudenreichii JS7 strain increases faster in anaerobic oxygen concentration comparing to aerobic and two staged oxygen concentrations. Based on the results of the bioreactor study, the bacterium can anaerobically form different size of colonies for the cell plating. The bacteriophage genome may be present as a plasmid, free and integrated into the bacterial chromosome. The results of the bacteriophage study might give signs that P. freudenreichii JS7 could be able to utilize the lysogenic life cycle in anaerobic growth condition.