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  • Raheem, Bamidele (Helsingin yliopisto, 2006)
    African indigenous foods have received limited research. Most of these indigenous foods are fermented and they form part of the rich nutritional culture of many groups in African countries. The industrialization and commercialisation of these indigenous African fermented foods should be preceded by a thorough scientific knowledge of their processing which can be vital in the elimination of hunger and poverty. This study highlighted emerging developments and the microbiology of cereal-based and cassava-based food products that constitute a major part of the human diet in most African countries. In addition, investigations were also carried out on the coagulant of the Calotropis procera plant used in traditional production of Nigerian Wara cheese and on the effects of adding a nisin producing Lactococcus lactis strain originating from human milk to Nigerian Wara cheese. Fermented cereal-based food such as ogi utilize popular African and readily available grains maize, millet or sorghum as substrates and is popular as a weaning diet in infants. In this study, the bulkiness caused by starch gelatinization was solved by amylase treatments in the investigation on cooked and fermented oat bran porridge. A similar treatment could reduce the viscosity of any cereal porridge. The properties of the Sodom apple leaves (Calotropis procera) extract in cheesemaking were studied. C. procera was affected by monovalent (K+ and Na+) and divalent (Mg2+ and Ca2+) cations during coagulation. The rennet strength of this coagulant was found to be 7 % compared to animal rennet at 35 °C. Increasing the incubation temperature to 70 °C increased the rennet strength 28-fold. The molecular weight of the partially purified protease was determined by SDS-PAGE and was confirmed by Zymography to be approximately 60 kilodaltons. The high proteolytic activity at 70 °C supported the suitability of the protease enzyme as a coagulant in future commercial production of Nigerian Wara cheese. It was also possible to extend the shelf life of Wara cheese by a nisin producing lactic acid bacteria Lactococcus lactis LAC309. The levels of nisin in both whey and curd fractions of Wara were investigated, results showed a 3 log reduction of toxicogenic Bacillus licheniformis spiked on Wara after 3 days. These studies are the first in Finland to promote the advancement of scientific knowledge in African foods. Recognizing these indigenous food products and an efficient transfer of technology from the developed countries to industrialize them are necessary towards a successful realization of the United Nations Millenium Development Program.
  • Honkonen, Ilja (Helsingin yliopisto, 2013)
    Currently the majority of space-based assets are located inside the Earth's magnetosphere where they must endure the effects of the near-Earth space environment, i.e. space weather, which is driven by the supersonic flow of plasma from the Sun. Space weather refers to the day-to-day changes in the temperature, magnetic field and other parameters of the near-Earth space, similarly to ordinary weather which refers to changes in the atmosphere above ground level. Space weather can also cause adverse effects on the ground, for example, by inducing large direct currents in power transmission systems. The performance of computers has been growing exponentially for many decades and as a result the importance of numerical modeling in science has also increased rapidly. Numerical modeling is especially important in space plasma physics because there are no in-situ observations of space plasmas outside of the heliosphere and it is not feasible to study all aspects of space plasmas in a terrestrial laboratory. With the increasing number of computational cores in supercomputers, the parallel performance of numerical models on distributed memory hardware is also becoming crucial. This thesis consists of an introduction, four peer reviewed articles and describes the process of developing numerical space environment/weather models and the use of such models to study the near-Earth space. A complete model development chain is presented starting from initial planning and design to distributed memory parallelization and optimization, and finally testing, verification and validation of numerical models. A grid library that provides good parallel scalability on distributed memory hardware and several novel features, the distributed cartesian cell-refinable grid (DCCRG), is designed and developed. DCCRG is presently used in two numerical space weather models being developed at the Finnish Meteorological Institute. The first global magnetospheric test particle simulation based on the Vlasov description of plasma is carried out using the Vlasiator model. The test shows that the Vlasov equation for plasma in six-dimensionsional phase space is solved correctly by Vlasiator, that results are obtained beyond those of the magnetohydrodynamic (MHD) description of plasma and that global magnetospheric simulations using a hybrid-Vlasov model are feasible on current hardware. For the first time four global magnetospheric models using the MHD description of plasma (BATS-R-US, GUMICS, OpenGGCM, LFM) are run with identical solar wind input and the results compared to observations in the ionosphere and outer magnetosphere. Based on the results of the global magnetospheric MHD model GUMICS a hypothesis is formulated for a new mechanism of plasmoid formation in the Earth's magnetotail.
  • Länsimäki, Maija-Liisa (1982)
  • Kuukasjärvi, Pirkko (1960)
  • Katila, Pia (Helsingin yliopisto, 2008)
    The study focused on the different ways that forest-related rights can be devolved to the local level according to the current legal frameworks in Laos, Nepal, Vietnam, Kenya, Mozambique and Tanzania. The eleven case studies represented the main ways in which forest-related rights can be devolved to communities or households in these countries. The objectives of this study were to 1) analyse the contents and extent of forest-related rights that can be devolved to the local level, 2) develop an empirical typology that represents the main types of devolution, and 3) compare the cases against a theoretical ideal type to assess in what way and to what extent the cases are similar to or differ from the theoretical construct. Fuzzy set theory, Qualitative Comparative Analysis and ideal type analysis were used in analysing the case studies and in developing an empirical typology. The theoretical framework, which guided data collection and analyses, was based on institutional economics and theories on property rights, common pool resources and collective action. On the basis of the theoretical and empirical knowledge, the most important attributes of rights were defined as use rights, management rights, exclusion rights, transfer rights and the duration and security of the rights. The ideal type was defined as one where local actors have been devolved comprehensive use rights, extensive management rights, rights to exclude others from the resource and rights to transfer these rights. In addition, the rights are to be secure and held perpetually. The ideal type was used to structure the analysis and as a tool against which the cases were analysed. The contents, extent and duration of the devolved rights varied greatly. In general, the results show that devolution has mainly meant the transfer of use rights to the local level, and has not really changed the overall state control over forest resources. In most cases the right holders participate, or have a limited role in the decision making regarding the harvesting and management of the resource. There was a clear tendency to devolve the rights to enforce rules and to monitor resource use and condition more extensively than the powers to decide on the management and development of the resource. The empirical typology of the cases differentiated between five different types of devolution. The types can be characterised by the devolution of 1) restricted use and control rights, 2) extensive use rights but restricted control rights, 3) extensive rights, 4) insecure, short term use and restricted control rights, and 5) insecure extensive rights. Overall, the case studies conformity to the ideal type was very low: only two cases were similar to the ideal type, all other cases differed considerably from the ideal type. The restricted management rights were the most common reason for the low conformity to the ideal type (eight cases). In three cases, the short term of the rights, restricted transfer rights, restricted use rights or restricted exclusion rights were the reason or one of the reasons for the low conformity to the ideal type. In two cases the rights were not secure.
  • Honkavaara, Juhana (Helsingin yliopisto, 2012)
    The effects of MK-467, a peripherally acting α2-adrenoceptor antagonist, on the cardiopulmonary changes induced by dexmedetomidine, a specific and selective α2- adrenoceptor agonist, were investigated in dogs. Plasma concentrations of both drugs were also quantified, along with influence of MK-467 on the quality of clinical sedation achieved with dexmedetomidine. The main focus of this study was on preventing or attenuating the cardiovascular effects of dexmedetomidine. The effects of three different doses of MK-467, administered simultaneously with the agonist, on the main hemodynamic parameters were evaluated and compared with a single dose of both dexmedetomidine and MK- 467 administered alone. Respiratory effects were evaluated with arterial blood gases, and indices such as oxygen delivery were calculated. The pharmacokinetic interaction between the two drugs was evaluated in vivo and general information on the disposition of intravenously administered MK-467 in dogs was produced. The degree of clinical sedation was subjectively assessed during the studies. The effect of MK-467 on the quality of reversal of dexmedetomidine-induced sedation with atipamezole was also determined. M K-467 dose-dependently reduced or prevented all relevant cardiovascular changes induced by dexmedetomidine. The heart rate, arterial and central venous blood pressure, cardiac index, systemic vascular resistance and oxygen delivery remained within acceptable physiological limits throughout the observational period with all doses of MK-467 administered with the agonist. Moderate hypotension was seen with the highest dose of MK-467. No significant differences in respiratory function were observed between treatments. MK-467, when administered alone, induced sinus tachycardia along with increases in the cardiac index and reductions in systemic vascular resistance. Arterial blood pressures remained unchanged. The degree of clinical sedation was reduced by MK-467, most likely by increasing the disposition of dexmedetomidine, which led to lower plasma concentrations of the agonist. However, the differences in clinical sedation were minor. MK-467 did not interfere with the ability of atipamezole to reverse dexmedetomidine-induced sedation.
  • Beijar, Katarina (2000)
    Syftet med denna studie var att undersöka i vilken utsträckning boendeformen kan sägas påverka de äldres upplevelser av ensamhet vid grupphem. Det som särskilt intresserade mig var om ensamhet uppkommer på äldre dagar eller om det är en känsla som i varierande grad finns inom individen. Jag har också varit intresserad av den negtiva aspekten av ensamhet och hur ensamhetskänslor skulle kunna avhjälpas. Det intresserade mig också att undersöka om man kan tala om positiv ensamhet. Under forskningens gång blev jag intresserad av hur ensamheten relaterades till språk, mat och vardag. Jag intervjuade år 1997 tio åldringar, åtta kvinnor och två män. De var då 69-89 år gamla. Jag använde halvstrukturerad temaintervju som metod och utgick i intervjuerna från Weiss' (1973) teori om social och emotionell isolering. Resultatet blev ganska mycket annorlunda än vad jag hade tänkt mig mycket beroende på att jag medvetet frågade annat än vad som direkt hade med ensamhet att göra. Kunde ensamheten relateras till gruppboende som bostadsform? Enligt min mening kan man inte dra sådana slutsatser. Det sociala livet upplevdes inte som speciellt givande och nästan alla intervjuade drog sig undan till sina rum. Enligt Tornstams gerotranscendensteori är det naturligt för de äldre att dra sig undan och förbereda sig inför döden. Robert Weiss teori om emotionell isolering passar in på dessa människor som inte upplevde gemenskap med varandra. Nästan ingen kände att de behövdes och denna känsla kan också hänföras till Weiss' teori om emotionell isolering. Tid, funktionsförmåga och hälsa tycktes inverka på hur invånarna trivdes i grupphemmen. Den som hade känt sig ensam tidigare i livet kände sig fortfarande ensam och den som hade haft få kontakter tidigare men ändå varit nöjd var det fortfarande. Största förändringen upplevde kanske de som börjat känna sig ensamma på äldre dagar. Gruppbostad som boendeform verkar enligt min mening fungera bra för de äldre trots att de framförde en visst missnöje med bostadssituationen. Den kritik som framfördes skulle säkert också ha förekommit gällande andra typer av institutionsboende.
  • Peiponen, Susanna (2008)
    Several canine clinical gastrointestinal problems, such as inflammatory bowel disease and small-intestinal bacterial overgrowth, are believed to be associated with bacteria. These conditions often lead to chronic diarrhea. Many canine gastrointestinal problems are treated with antibiotics, but due to increasing problems with antimicrobial resistance alternative therapies should be considered. One of these therapies is suggested be probiotic bacteria treatment, especially with members of the genus Lactobacillus due to their health-conferring properties. The probiotic characteristics of bacteria are linked to host specificity which is an important criterion for selection of a probiotic. Most of the commercial probiotic strains meant for dogs are not from canine origin. In addition many substances available in the Finnish market contain Enterococcus faecium, whose safety has been questioned due to it's pathogenic characteristics. This study was based on the study project investigating the effect of host-specific canine LAB on long term gastro-intestinal symptoms. The study was a randomized, double-blinded and placebo controlled trial. This study examined the changes in the canine faecal LAB microbiota caused by fed canine host-specific probiotic LAB. The purpose was to become familiar to the isolation of gastro-intestinal microbiota and to assess the potential alterations in the faeces by applicable methods. The most important methods were polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE). During the study DGGE analysis proved to be a working method for analyzing bacterial communities. When the method becomes more familiar, it will probably be as common in use as agarose gel electrophoresis due to it's advantages. Some alterations of the microbiota could be seen on the DGGE analysis. During the experiment the bands resembling those of standard strains were dominant. This implies the Lactobacillus strains of interest being able to survive the canine intestine. However, after feeding seized the bands formed by the strains of interest disappeared and were replaced with bands of indigenous LAB. Also after the feeding seized, some new bands appeared on DGGE gel. This implies a contribution of fed probiotic mixture to the enhanced prevalence of potential novel microbes.
  • Honkasalo, Mikko (Helsingin yliopisto, 2015)
    Diabetes is a common chronic disease with growing prevalence in Finland like worldwide. It shortens the life expectancy and the quality of life. Despite the development in medication and devices there has been only modest improvement in the outcome, especially among type 1 diabetic patients. The aim of this study was to compare the outcome of overall diabetes care in municipalities with different primary health care models of organising the follow-up of type 1 diabetes and type 2 diabetes with special treatment problems. The study also aimed at estimating the feasibility of various indicators of the standard of diabetes care. The outcome, use and costs of health services connected with diabetes and its complications were compared in two suburban communities, Kouvola and Nurmijärvi. In Kouvola the follow-up of all patients had been based on family doctors already over 15 years whereas in Nurmijärvi the follow-up of T1D patients and the complicated T2D patients had been centralized to 1-2 doctors for the same time. The diabetic populations of these municipalities resembled each other. In the centralized system T1D became cheaper for the municipality. Differences in the quality parameters were minor. Both these results were obviously due to more consultations of the specialist level in Kouvola. However, T1D patients were significantly more satisfied with the centralized follow-up model. In conclusion, the centralized follow-up of the most demanding diabetes in PHC is cost-effective and results in high patient satisfaction. The centralized model is better in the follow-up of T1D but in T2D there were no differences between these two models.
  • Rosenback Susanna (Helsingfors universitet, 2010)
    Syftet med studien var att undersöka sambanden mellan de diabetesassocierade autoantikropparna ICA, IAA, GADA, IA-2A och klinisk manifestation, HLA-genotyp, släktanamnes samt demografiska faktorer såsom ålder och kön hos finländska barn under 15 år med nydiagnostiserad typ 1 diabetes. Analyserna baserades på ett utdrag ur det finländska pediatriska diabetesregistret (2257 barn). Antikroppsfrekvenserna fastställdes utgående från halterna i serum. Alla barn HLA-genotypades och indelades i DR3- och DR4-positiva. Småbarnen (?5 år) hade ofta 3-4 positiva antikroppar. Äldre barn hade färre autoantikroppar men en allvarligare metabolisk dekompensering vid diagnostillfället. Diabetisk ketoacidos var vanligare hos flickor. I gruppen med endast en positiv autoantikropp var IA-2A-barnen oftare acidotiska, i övrigt påverkade inte antikroppsprofilen den kliniska bilden. Högriskgenotypen DR4/non-DR3 var associerad med IA-2A, som verkar fungera som en markör för betacelldestruktion. Det omfattande patientmaterialet gav stöd åt tidigare rapporter om samband mellan autoantikroppar och ålder, kön samt genotyp. Den allvarligare metaboliska dekompenseringen hos äldre barn tyder på att de inte diagnostiseras lika snabbt som småbarn.