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  • Hirvonen, Juho (2012)
    In this work we study a graph problem called edge packing in a distributed setting. An edge packing p is a function that associates a packing weight p(e) with each edge e of a graph such that the sum of the weights of the edges incident to each node is at most one. The task is to maximise the total weight of p over all edges. We are interested in approximating a maximum edge packing and in finding maximal edge packings, that is, edge packings such that the weight of no edge can be increased. We use the model of distributed computing known as the LOCAL model. A communication network is modelled as a graph, where nodes correspond to computers and edges correspond to direct communication links. All nodes start at the same time and they run the same algorithm. Computation proceeds in synchronous communication rounds, during each of which each node can send a message through each of its communication links, receive a message from each of its communication links, and then do unbounded local computation. When a node terminates the algorithm, it must produce a local output – in this case a packing weight for each incident edge. The local outputs of the nodes must together form a feasible global solution. The running time of an algorithm is the number of steps it takes until all nodes have terminated and announced their outputs. In a typical distributed algorithm, the running time of an algorithm is a function of n, the size of the communication graph, and Δ, the maximum degree of the communication graph. In this work we are interested in deterministic algorithms that have a running time that is a function of Δ, but not of n. In this work we will review an O(log Δ)-time constant-approximation algorithm for maximum edge packing, and an O(Δ)-time algorithm for maximal edge packing. Maximal edge packing is an example of a problem where the best known algorithm has a running time that is linear-in-Δ. Other such problems include maximal matching and (Δ+1)-colouring. However, few matching lower bounds exist for these problems: by prior work it is known that finding a maximal edge packing requires time Ω(log Δ), leaving an exponential gap between the best known lower and upper bounds. Recently Hirvonen and Suomela (PODC 2012) showed a linear-in-Δ lower bound for maximal matching. This lower bound, however, applies only in weaker, anonymous models of computation. In this work we show a linear-in-Δ lower bound for maximal edge packing. It applies also in the stronger port numbering model with orientation. Recently Göös et al. (PODC 2012) showed that for a large class of optimisation problems, the port numbering with orientation model is as powerful as a stronger, so called unique identifier model. An open question is if this result can applied to extend our lower bound to the unique identifier model.
  • Mäki, Jussi Olavi Aleksis (2013)
    With the increasing growth of data traffic in mobile networks there is an ever growing demand from the operators for a more scalable and cost efficient network core. Recent successes in deploying Software-Defined Networking (SDN) in data centers and large network backbones has given it credibility as a viable solution for meeting the requirements of even the large core networks. Software-Defined Networking is a novel new paradigm where the control logic of the network is separated from the network elements into logically centralized controllers. This separation of concerns offers more flexibility in network control and makes writing of new management applications, such as routing protocols, easier, faster and more manageable. This thesis is an empirical experiment in designing and implementing a scalable and fault- tolerant distributed SDN controller and management application for managing the GPRS Tunneling Protocol flows that carry the user data traffic within the Evolved Packet Core. The experimental implementation is built using modern open-source distributed system tools such as the Apache Zookeeper distributed coordination service and Basho’s Riak distributed key-value database. In addition to the design, a prototype implementation is presented and its performance is evaluated.
  • Vainionpää, Noora (nyk. Noora Skants) (Helsingin yliopisto, 2008)
    Basement membranes are specialized sheets of extracellular matrix found in contact with epithelia, endothelia, and certain isolated cells. They support tissue architecture and regulate cell behaviour. Laminins are among the main constituents of basement membranes. Due to differences between laminin isoforms, laminins confer structural and functional diversity to basement membranes. The first aim of this study was to gain insights into the potential functions of the then least characterized laminins, alpha4 chain laminins, by evaluating their distribution in human tissues. We thus created a monoclonal antibody specific for laminin alpha4 chain. By immunohistochemistry, alpha4 chain laminins were primarily localized to basement membranes of blood vessel endothelia, skeletal, heart, and smooth muscle cells, nerves, and adipocytes. In addition, alpha4 chain laminins were found in the region of certain epithelial basement membranes in the epidermis, salivary gland, pancreas, esophagus, stomach, intestine, and kidney. Because of the consistent presence of alpha4 chain laminins in endothelial basement membranes of blood vessels, we evaluated the potential roles of endothelial laminins in blood vessels, lymphatic vessels, and carcinomas. Human endothelial cells produced alpha4 and alpha5 chain laminins. In quantitative and morphological adhesion assays, human endothelial cells barely adhered to alpha4 chain-containing laminin-411. The weak interaction of endothelial cells with laminin-411 appeared to be mediated by alpha6beta1 integrin. The alpha5 chain-containing laminin-511 promoted endothelial cell adhesion better than laminin-411, but it did not promote the formation of cell-extracellular matrix adhesion complexes. The adhesion of endothelial cells to laminin-511 appeared to be mediated by Lutheran glycoprotein together with beta1 and alphavbeta3 integrins. The results suggest that these laminins may induce a migratory phenotype in endothelial cells. In lymphatic capillaries, endothelial basement membranes showed immunoreactivity for laminin alpha4, beta1, beta2, and gamma1 chains, type IV and XVIII collagens, and nidogen-1. Considering the assumed inability of alpha4 chain laminins to polymerize and to promote basement membrane assembly, the findings may in part explain the incomplete basement membrane formation in these vessels. Lymphatic capillaries of ovarian carcinomas showed immunoreactivity also for laminin alpha5 chain and its receptor Lutheran glycoprotein, emphasizing a difference between normal and ovarian carcinoma lymphatic capillaries. In renal cell carcinomas, immunoreactivity for laminin alpha4 chain was found in stroma and basement membranes of blood vessels. In most tumours, immunoreactivity for laminin alpha4 chain was also observed in the basement membrane region of tumour cell islets. Renal carcinoma cells produced alpha4 chain laminins. Laminin-411 did not promote adhesion of renal carcinoma cells, but inhibited their adhesion to fibronectin. Renal carcinoma cells migrated more on laminin-411 than on fibronectin. The results suggest that alpha4 chain laminins have a counteradhesive function, and may thus have a role in detachment and invasion of renal carcinoma cells.
  • Nurmi, Satu (2015)
    Many drugs are known to bind to melanin, a complex pigment polymer found in several human tissues. Melanin can act as a natural depot by prolonging the effect of the drug and reducing its toxicity. Since it is highly concentrated in the posterior part of the eye, pigment targeted long-acting drug delivery systems are proposed as an option in ocular diseases. In systemic drug delivery, pigment targeted drugs can potentially distribute to any melanin containing tissue. Therefore, the literature review of the thesis concentrates on the characteristics of melanin and melanosomes, drug binding property and melanin distribution in humans and other species. The main objective of the exploratory part was to determine if melanin binding can be studied with SPECT/CT (single photon emission computed tomography / computed tomography) imaging method. Two different melanin binding drugs, chloroquine and nadolol, were selected and labeled with iodine and radioactive iodine (123I). Equilibrium melanin binding of iodinated and non-iodinated drugs was studied in vitro in order to find out if iodination affects to the binding. Melanin binding was studied in vitro also with non-binding reference salicylic acid, I2-salicylic acid and salbutamol. Finally, melanin binding of 123I-choloroquine and 123I-nadolol was studied with SPECT/CT (NanoSPECT/CT, Bioscan Inc., USA) by comparing distribution kinetics between pigmented and albino rat. Drugs were administered intravenously to the tail vena and the distribution was followed in several time points, up to 24 h. Based on in vitro study, iodination increases melanin binding of hydrophilic drugs, nadolol and salicylic acid, significantly. In vivo study showed clear accumulation of 123I-chloroquine in the posterior eye of pigmented rats whereas it was absent from albino rat. Interestingly, 123I-nadolol accumulated in to the nasal cavity of pigmented rats. Aromatic iodination changes electronegative properties of compounds and raises their logP (octanol/water partition coefficient) value affecting to the melanin binding positively. Therefore the effect of the radiotracer to the physicochemical properties of the compound and melanin binding should be determined in vitro. This study showed that SPECT/CT imaging method can be used to study melanin binding in vivo. Because the method is semi-quantitative, also a quantitative method should be incorporated to the study in order to have more powerful data. Additional studies are required for statistical analysis.
  • Nurmi, Satu (2014)
    Many drugs are known to bind to melanin, a complex pigment polymer found in several human tissues. Melanin can act as a natural depot by prolonging the effect of the drug and reducing its toxicity. Since it is highly concentrated in the posterior part of the eye, pigment targeted long-acting drug delivery systems are proposed as an option in ocular diseases. In systemic drug delivery, pigment targeted drugs can potentially distribute to any melanin containing tissue. Therefore, the literature review of the thesis concentrates on the characteristics of melanin and melanosomes, drug binding property and melanin distribution in humans and other species. The main objective of the exploratory part was to determine if melanin binding can be studied with SPECT/CT (single photon emission computed tomography / computed tomography) imaging method. Two different melanin binding drugs, chloroquine and nadolol, were selected and labeled with iodine and radioactive iodine (123I). Equilibrium melanin binding of iodinated and non-iodinated drugs was studied in vitro in order to find out if iodination affects to the binding. Melanin binding was studied in vitro also with non-binding reference salicylic acid, I2-salicylic acid and salbutamol. Finally, melanin binding of 123I-choloroquine and 123I-nadolol was studied with SPECT/CT (NanoSPECT/CT, Bioscan Inc., USA) by comparing distribution kinetics between pigmented and albino rat. Drugs were administered intravenously to the tail vena and the distribution was followed in several time points, up to 24 h. Based on in vitro study, iodination increases melanin binding of hydrophilic drugs, nadolol and salicylic acid, significantly. In vivo study showed clear accumulation of 123I-chloroquine in the posterior eye of pigmented rats whereas it was absent from albino rat. Interestingly, 123I-nadolol accumulated in to the nasal cavity of pigmented rats. Aromatic iodination changes electronegative properties of compounds and raises their logP (octanol/water partition coefficient) value affecting to the melanin binding positively. Therefore the effect of the radiotracer to the physicochemical properties of the compound and melanin binding should be determined in vitro. This study showed that SPECT/CT imaging method can be used to study melanin binding in vivo. Because the method is semi-quantitative, also a quantitative method should be incorporated to the study in order to have more powerful data. Additional studies are required for statistical analysis.
  • Nyman, Marjut (Helsingin yliopisto, 2007)
    Climate change contributes directly or indirectly to changes in species distributions, and there is very high confidence that recent climate warming is already affecting ecosystems. The Arctic has already experienced the greatest regional warming in recent decades, and the trend is continuing. However, studies on the northern ecosystems are scarce compared to more southerly regions. Better understanding of the past and present environmental change is needed to be able to forecast the future. Multivariate methods were used to explore the distributional patterns of chironomids in 50 shallow (≤ 10m) lakes in relation to 24 variables determined in northern Fennoscandia at the ecotonal area from the boreal forest in the south to the orohemiarctic zone in the north. Highest taxon richness was noted at middle elevations around 400 m a.s.l. Significantly lower values were observed from cold lakes situated in the tundra zone. Lake water alkalinity had the strongest positive correlation with the taxon richness. Many taxa had preference for lakes either on tundra area or forested area. The variation in the chironomid abundance data was best correlated with sediment organic content (LOI), lake water total organic carbon content, pH and air temperature, with LOI being the strongest variable. Three major lake groups were separated on the basis of their chironomid assemblages: (i) small and shallow organic-rich lakes, (ii) large and base-rich lakes, and (iii) cold and clear oligotrophic tundra lakes. Environmental variables best discriminating the lake groups were LOI, taxon richness, and Mg. When repeated, this kind of an approach could be useful and efficient in monitoring the effects of global change on species ranges. Many species of fast spreading insects, including chironomids, show a remarkable ability to track environmental changes. Based on this ability, past environmental conditions have been reconstructed using their chitinous remains in the lake sediment profiles. In order to study the Holocene environmental history of subarctic aquatic systems, and quantitatively reconstruct the past temperatures at or near the treeline, long sediment cores covering the last 10000 years (the Holocene) were collected from three lakes. Lower temperature values than expected based on the presence of pine in the catchment during the mid-Holocene were reconstructed from a lake with great water volume and depth. The lake provided thermal refuge for profundal, cold adapted taxa during the warm period. In a shallow lake, the decrease in the reconstructed temperatures during the late Holocene may reflect the indirect response of the midges to climate change through, e.g., pH change. The results from three lakes indicated that the response of chironomids to climate have been more or less indirect. However, concurrent shifts in assemblages of chironomids and vegetation in two lakes during the Holocene time period indicated that the midges together with the terrestrial vegetation had responded to the same ultimate cause, which most likely was the Holocene climate change. This was also supported by the similarity in the long-term trends in faunal succession for the chironomid assemblages in several lakes in the area. In northern Finnish Lapland the distribution of chironomids were significantly correlated with physical and limnological factors that are most likely to change as a result of future climate change. The indirect and individualistic response of aquatic systems, as reconstructed using the chironomid assemblages, to the climate change in the past suggests that in the future, the lake ecosystems in the north do not respond in one predictable way to the global climate change. Lakes in the north may respond to global climate change in various ways that are dependent on the initial characters of the catchment area and the lake.
  • Ilmonen, Lotta (2003)
    Stamceller definieras ofta enligt det organ de befinner sig i. Det antas att stamceller från ett visst organ kan ge upphov till alla celler av detta organ och bara till dessa celler. Därför har färska forskningar väckt uppmärksamhet då de påvisat att stamceller kan välja otypiska specialiceringslinjer. Experiment har utförts på bestrålade djur. Det har varit oklart vilken betydelse donatorns stamceller har på mottagarens tillväxt i fysiologiska tillstånd. I denna studie har vi använt kimeriska tvillingkalvar i vilkas nonhematopoetiska vävnader donatorns stamceller har spårats. Med tvillingar av olika kön resulterar placentala anastomoser i tidig embryonal utveckling, i en kimerisk, steril kokalv som kallas freemartin. Med hjälp av Y-kromosom riktad in situ hybridisering kan vi spåra donatorns, tjurkalvens celler i mottagarens, freemartin-kalvens vävnader i deras naturliga omgivning. Hematopoetiska celler spårades med att identifiera deras CD45 yt-antigen och kunde därmed, i kombination med in situ hybridiseringen ekskluderas. Vi har hittat nonhematopoetiska celler härstammande från donatorn i vävnader vars ursprung är långt från varandra, så som entodermet och nerv stängen. Nonhematopoetiska celler som härstammar från donatorn var fåtaliga och de var sporadiskt utspridda i vävnaderna. Detta föreslår att de har ringa betydelse i det fysiologiska uppehållet och i utvecklingen av nötkreaturens vävnader.
  • Schendzielorz, Nadia (Helsingin yliopisto, 2012)
    Catechol-O-methyltransferase (COMT) metabolises catecholamines such as dopamine, noradrenaline and adrenaline, which are well-characterised neurotransmitters that play important roles in the regulation of physiological processes. The COMT enzyme exists in membrane-bound (MB-COMT) and soluble (S-COMT) forms that are both encoded by the same gene. Presently, the necessity and physiological importance of the existence of two COMT isoenzymes remains partially unknown. The aim of this thesis was to provide new insights into the specific distribution patterns of MB-COMT and S-COMT, to verify the proposed hormonal regulation of COMT and to investigate its possible physiological role in feeding behaviour. We used two different study designs to address the distribution of COMT in the brain. First, we utilised dopaminergic and noradrenergic toxins to assess the presence of COMT in presynaptic neurons originating from selected brain areas. Successful lesioning of the neurons was confirmed by measuring dopamine and noradrenaline levels in their respective projection areas. However, despite successful lesioning, no changes in COMT protein expression or activity could be noted, indicating that COMT is not present in presynaptic dopaminergic and noradrenergic neurons. The specific distribution patterns of MB-COMT and S-COMT were studied in an S-COMT-deficient mouse line (lacking the S-COMT form of COMT). By comparing these mice to wild type mice, we found that the general distribution patterns of both COMT isoforms were similar between the genotypes. Notably, S-COMT-deficient mice did not exhibit nuclear COMT staining, indicating that MB-COMT is not present in cell nuclei. Furthermore, S-COMT-deficient mice allowed us to examine the association of MB-COMT with the plasma membrane. Contrary to previous assumptions, MB-COMT is not associated with the plasma membrane, but instead may be attached to intracellular cytosolic membranes. The proposed regulatory function of oestrogens on COMT activity was studied by subjecting male and female Wistar rats to different hormonal treatments over a two-week period. Antagonising/modulating the effects of oestrogen via the administration of tamoxifen increased COMT activity and expression. Unexpectedly, increasing oestradiol levels in male rats also led to the upregulation of COMT expression in several tissues, underscoring the importance of COMT in the clearance of biologically active oestrogen metabolites. Finally, we used female rodents (rats and mice) to address the possible role of COMT in feeding behaviour. Our studies revealed that acute COMT inhibition affects the feeding pattern of rodents; COMT-inhibited animals have significantly more ''long'' meals (lasting 300 sec or more) than vehicle-treated animals. Notably, a relatively short starvation period of 16 h induced a slight, albeit not significant, decrease in prefrontal and striatal COMT activity in mice. This finding is interesting, especially as COMT activity is thought to be rather robust, and may suggest the increased importance of COMT during altered physiological status. In conclusion, although the specific roles of MB-COMT and S-COMT remain partly obscure, their absence from presynaptic dopaminergic and noradrenergic neuron terminals suggests a secondary (and perhaps more modulatory) role of COMT in neurotransmitter metabolism in the brain. Furthermore, the observed decrease in COMT activity after a relatively short starvation period suggests that COMT has an increased importance during certain physiological states. Finally, the observed regulatory function of oestrogens on COMT activity and protein expression in vivo may be of clinical importance as COMT inhibitors are used as adjuncts in the treatment of PD.
  • Hautala, Harri (Helsingin yliopisto, 2008)
    The immediate effects of two human-related vegetation disturbances, (1) green tree retention (GTR) patch felling and scarification by harrowing and (2) experimental understorey vegetation layer removal, were examined in boreal forest stands in Finland. Effects of GTR patch felling and scarification on tree uprootings, on coarse woody debris (CWD) and on epixylic plant community were followed in upland and in paludified forest types. Uprootings increased considerably during 2-3 years after the fellings and were more frequent (47%) in the paludified than in the upland forest (13%). Scarification reduced 68% of the CWD in the felling area. Cover and especially species richness of epixylics declined in the both areas during 1-2 years after the felling. The increasing size of GTR patch correlated positively with the species richness. Regeneration of understorey vegetation community and Vaccinium myrtillus and Vaccinium vitis-idaea after different removals of vegetation layers in an old-growth forest took four years. The regeneration occurred mainly by vegetative means and it was faster in the terms of species richness than in the cover. In the most severe treatment, recovery occurred merely by sexual reproduction. V. myrtillus recovered mainly by producing new shoots. V. vitis-idaea recovered faster than V. myrtillus, mainly by increasing length growth. For ecological reasons, use of larger GTR patches on paludified biotope would be recommendable. In felling areas, scarification by harrowing could be replaced with some other spot-wise method. After moderate intensity level disturbance, recovery occurs rapidly by vegetative regrowth of the dominating species. High level of intensity may prevent the recovery of vegetation community for years, while enabling also the genetic regeneration of the initial species. Local anthropogenic-related disturbances are currently increasing and they can interact during temporally short times, which should be taken in to account in the future forest management plans.
  • Rauramo, Suvi (2000)
    Tutkielmassa tarkastellaan, millaisia kerronnallisia konventioita tietokonepelit käyttävät temmatakseen pelaajan "sisään" tarinamaailmaan. Komparatiivista lähestymistapaa soveltaen tutkielma pyrkii kartoittamaan yhteneväisyyksiä ja eroavaisuuksia tietokonepelien ja aikaisempien audiovisuaalisten medioiden välillä. Tutkimuksen empiirisenä aineistona on 36 PlayStation- ja PC-peliä vuosilta 1996-2000. Elokuvan kerronnan teoriaa hyväksi käyttäen eritellään, miten tietokonepeleissä käytetään audiovisuaalisen kerronnan elementtejä. Pelin maailmarakenne nousee keskeiseksi jäsentäväksi tekijäksi. Maailman taustalla oleva looginen rakenne viime kädessä säätelee pelaamista. Maailma rajoittaa pelaajan toimintaa huomattavasti, vaikka peli pyrkiikin usein kätkemään rajoitukset diegeettisesti. Maailman yhtenäisyys ja jatkuvuus ovat elintärkeitä spatiaalisen immersion luomisen kannalta. Tutkielma vahvistaa, että navigointi maailmassa on keskeinen kerronnallinen voima. Fokalisoijahahmon liikuttaminen tai nondiegeettisen näkymän kontrollointi vaikuttaa tarinan purkautumiseen, kameran liikkeeseen, otosten siirtymiin sekä joskus myös kerronnallisen näkökulman vaihteluun. Kerronnallisten peruselementtien - maailman, sen rajauksen ja sen sisäisten siirtymien - analysoinnin perusteella tutkielmassa muodostetaan tietokonepeleille tyypilliset kerronnalliset näkökulmat. Tietokonepelit käyttävät useita kerronnallisia näkökulmia: ensimmäisen persoonan näkökulmaa, seuraajanäkökulmaa, neljännen seinän näkökulmaa, lintunäkökulmaa tai jumalnäkökulmaa. Kuitenkin yleensä vain yhtä tai kahta näkökulmaa käytetään kussakin pelissä. Hahmo on alisteisessa asemassa maailmaan nähden silloinkin, kun hahmo on fokalisoija. Tätä korostaa kuvan rajaaminen kaukaa: hahmo on (hyvin) pieni, kun taas ympäröivä maailma nousee pääosaan. Lisäksi kerronta on usein nondiegeettistä, jolloin näkymä ei ole lainkaan sidoksissa hahmoon. Maailma, eikä hahmo, on pelaajan huomion keskipiste. Pelien kerronta näyttää kehittyvän kohti lyhyempiä otospituuksia ja entistä monipuolisempaa kameran sijoittelua ja liikettä. Suuntaus vie entistä moninaisempiin kerronnallisiin näkökulmiin ja kerronnan tasoihin, mikä on perustavanlaatuinen edellytys kehittyneelle tarinankerronnalle. Keskeiset lähteet ovat Edward Braniganin Narrative comprehension and film (1992) ja Lev Manovichin The language of new media (ilmestyy 2000).
  • Hacklin, Saara (Helsingin yliopisto, 2012)
    Maurice Merleau-Ponty (1908-1961) has been known as the philosopher of painting. His interest in the theory of perception intertwined with the questions concerning the artist s perception, the experience of an artwork and the possible interpretations of the artwork. For him, aesthetics was not a sub-field of philosophy, and art was not simply a subject matter for the aesthetic experience, but a form of thinking. This study proposes an opening for a dialogue between Merleau-Pontian phenomenology and contemporary art. The thesis examines his phenomenology through certain works of contemporary art and presents readings of these artworks through his phenomenology. The thesis both shows the potentiality of a method, but also engages in the critical task of finding the possible limitations of his approach. The first part lays out the methodological and conceptual points of departure of Merleau-Ponty s phenomenological approach to perception as well as the features that determined his discussion on encountering art. Merleau-Ponty referred to the experience of perceiving art using the notion of seeing with (voir selon). He stressed a correlative reciprocity described in Eye and Mind (1961) as the switching of the roles of the visible and the painter. The choice of artworks is motivated by certain restrictions in the phenomenological readings of visual arts. The examined works include paintings by Tiina Mielonen, a photographic work by Christian Mayer, a film by Douglas Gordon and Philippe Parreno, and an installation by Monika Sosnowska. These works resonate with, and challenge, his phenomenological approach. The chapters with case studies take up different themes that are central to Merleau-Ponty s phenomenology: space, movement, time, and touch. All of the themes are interlinked with the examined artworks. There are also topics that reappear in the thesis, such as the notion of écart and the question of encountering the other. As Merleau-Ponty argued, the sphere of art has a particular capability to address our being in the world. The thesis presents an interpretation that emphasises the notion of écart, which refers to an experience of divergence or dispossession. The sudden dissociation, surprise or rupture that is needed in order for a meeting between the spectator and the artwork, or between two persons, to be possible. Further, the thesis suggests that through artworks it is possible to take into consideration the écart, the divergence, that defines our subjectivity.
  • Torsti, Pilvi (2003)
    Tutkimuksen tavoite oli kaksiosainen: historian käytön analysointi sodanjälkeisessä Bosnia ja Hertsegovinassa erityisesti nuorten näkökulmasta sekä Bosnian serbi-, kroaatti-, ja bosniakkinuorten historiallisen ajattelun tarkastelu. Tutkimustavoite konkretisoitui seuraavaan kolmeen pääanalyysiin: Analyyseista ensimmäinen käsitteli yleistä historian läsnäoloa sodanjälkeisessä Bosniassa. Jäsentelin analyysin historiallisten ilmiöiden, kuten historiakulttuurin, historiatietoisuuden ja historiapolitiikan ympärille. Toinen pääanalyysi keskittyi kolmeen erilliseen 8. luokan historian oppikirjaan (8. luokka on peruskoulun viimeinen luokka), joita Bosnian kolme kansallista ryhmää ovat käyttäneet sotavuosista lähtien. Koulukirjakäsittely rakentui sodan, rauhan ja kansakunnan käsitteiden ympärille. Keskuskäsitteiden katsotaan olevan keskeisiä yhteiskuntahistoriallisia käsitteitä sodanjälkeisessä Bosniassa. Kolmas pääanalyysi käsitteli kansainvälistä Nuoret ja Historia -tutkimusta, jonka keräsin kahdeksasluokkalaisilta bosnialaisilta 1999–2000. Nuorten historiallista ajattelua ja käsityksiä kuvannut tilastollinen analyysi perustui 907 oppilaan vastauksiin ja keskittyi samojen kolmen pääkäsitteen representaatioihin kuin oppikirja-analyysi. Bosnian kansallisten ryhmien vastauksia verrattiin muiden maiden tuloksiin sekä keskenään. Analyysi historian läsnäolosta kuvasti historiakulttuurin jakautumista kolmeen erilliseen ja osin jopa vastakkaiseen kulttuuriin sodanjälkeisessä Bosniassa. Historian oppikirjat havainnollistivat, kuinka kolmen kansanryhmän esitykset menneestä luovat viholliskuvia muista kansanryhmistä maan sisällä. Kirjat rakentavat kolmea erilaista historiantulkintaa neljän miljoonan asukkaan yhteiskunnan sisällä ja rinnastavat usein menneen ja nykyisen. Samaan aikaan Nuoret ja Historia –tutkimus osoitti, että valtaosassa kysymyksiä Bosnian kansalliset ryhmät erottuivat toisistaan vain marginaalisesti. Eurooppalaisessa vertailussa Bosnian nuoret muodostivat oman yksittäisen ryhmänsä: he uskoivat vahvasti rauhaan tulevaisuudessa eivätkä pitäneet sotia tärkeinä historian muutosvoimina.
  • Torsti, Pilvi (2003)
    The task of the research was binary: to determine the use of history in the post-war Bosnia and Herzegovina from the perspective of young people, and to define the historical thinking of youth among Bosnian Serbs, Croats and Bosniacs. The task coalesced into three main analyses. The first analysis discussed the general presence of history in post-war Bosnian society. The analysis was organised around history-related phenomena: history culture, historical consciousness and history politics. Three separate 8th-grade (the 8th grade is the last year of obligatory schooling) history textbooks used by the three Bosnian national communities were the subject of the second analysis, which focused on the representations of three socio-historical concepts central in post-war Bosnian society: war, peace and nation. The third analysis of the historical thinking of the youth was based on the international Youth and History survey which I conducted among 8th-grade pupils in Bosnia in 1999-2000. The descriptive statistic analysis of the answers of 907 pupils concentrated on the representations of the same three concepts as in the textbooks analysis. The answers of the Bosnian national groups were compared to each other and to other European country samples. The description of the presence of history illustrated the division of history culture into three separate – and even opposing – cultures in post-war Bosnia and Herzegovina. History textbooks further demonstrated how presentations of the past among the three communities create hostile images of the country’s other national groups. They construct three different interpretations of the past within a society of four million people often equating the past with the present. Finally, the Youth and History survey analysis showed that in most questions, the national groups differed only marginally in their thinking. In the European comparison, Bosnians formed a single group and demonstrated great belief in future peace and did not consider wars important factors of change in history.
  • Klingenberg, Daniela (2011)
    Bakteriesläktet Stenotrophomonas består av 12 arter. De existerar överallt i naturen, men speciellt S. maltophilia, S. rhizophila och S. pavanii är associerade med växter. Stammar av den mest förekommande arten, S. maltophilia, har konstaterats ha fördelaktiga effekter på växters tillväxt och hälsa, förmåga att bryta ner svårnerbrytbara föreningar samt producera biomolekyler av bioteknologiskt och ekonomiskt värde. Många S. maltophilia -stammar är även multiresistenta mot antibiotika och kan fungera som opportunistiska människopatogener. Under ett INCO-projekt (1998-2002) isolerades rhizobiestammar från det tropiska baljväxtträdet Calliandra calothyrsus Meisn. rotknölar från länder i Centralamerika, Afrika och Nya Kaledonien. Rhizobiekollektionen identifierades vid Kvävegruppen (Helsingfors universitet), där det framkom att en del stammar tillhörde släktet Stenotrophomonas. Många av Stenotrophomonas-stammarna inducerade i växtförsök vita, tumör- eller rotknölsliknande strukturer på Calliandra-plantors rötter. Bakterierna kunde förutom rotknölar även isoleras från ytsteriliserade rötter och stammar. Syftet med mitt arbete var att undersöka i) stammarnas arttillhörighet, ii) om stammarna har samma ursprung, iii) om det finns andra skillnader än koloniutseende mellan fasvariationer av samma stam, iv) har tillväxtfrämjande (eng. plant growth promoting, PGP) egenskaper eller annan fördelaktig inverkan på växter, och v) likt rhizobier har förmåga att inducera uppkomsten av rotknölar. För att kunna dra slutsatser om Stenotrophomonas-stammarnas geografiska ursprung undersöktes stammarnas genetiska diversitet och gruppering med AFLP-fingerprinting. Med hjälp av kommersiella API-test för bakterieidentifikation undersöktes skillnader mellan faserna vad beträffar enzymatiska egenskaper samt förmåga att använda olika kol- och energikällor. Stammarnas förmåga att infektera rothår och inducera rotknölar undersöktes både genom växtförsök med värdväxten Calliandra och genom PCR-amplifiering av stammarnas nodA- och nodC-gener för rotknölsbildning. Stammarnas PGP-aktivitet utreddes in vitro främst genom odlingsmetoder. Stenotrophomonas-bakteriernas inverkan in vivo på växternas tillväxt, kväveinnehåll och uppkomsten av rotknölar undersöktes genom växthusförsök med baljväxterna Phaseolus vulgaris och Galega orientalis. Både den genetiska och fenotypiska diversiteten hos Stenotrophomonas-stammarna var mycket liten, vilket indikerar att de har ett gemensamt ursprung. Stenotrophomonas-bakterierna fick till stånd förändringar i rothåren hos Calliandra-plantornas rötter och de ökade även mängden rothår. Däremot uppkom det inga rotknölar hos Calliandra-plantorna. Av de testade PGP-egenskaperna kunde stammarna producera IAA, proteas och lipas. De uppvisade även tillväxtfrämjande effekt på G. orientalis, både enskilt och vid saminokulering med R. galegae HAMBI 540 samt aktiverade effektiva rhizobiers rotknölsbildning hos P. vulgaris i växthus. Det krävs vidareforskning för att utreda vilka mekanismer de uppkomna positiva effekterna grundar sig på. Resultaten i detta arbete bekräftar dock tidigare forskningsresultat angående Stenotrophomonas-bakteriers positiva inverkan på växter.
  • Kautto, Mikko (2001)
    The thesis explores patterns of welfare state adjustment in Nordic welfare states in a Western European context, with a focus on changes in the 1990s. Its theoretical starting points are in the contemporary controversy between the power resource theory and the welfare regime approach that have underlined the role of ideology and politics as explanatory factors for the character of welfare states and their enduring divergence; and the new convergence thesis that sees 'external' factors, such as globalisation and EU, push for declining differences among welfare states. For both strands of thinking a crucial empirical question concerns how policy reforms affect diversity among welfare states, i.e. the patterning of differences and similarities that differentiate types of welfare states. To consider this problematic two research questions are formulated: Are there systematic patterns of differences among welfare states? Do welfare states converge over time? Empirically the study addresses variation and trends in statutory fiscal and welfare policies with the help of statistics, especially with Eurostat's social protection expenditure data. The study outlines an ideal typical picture of the Nordic welfare model for gauging change, and employs basic statistical parameters, tables, graphical methods and clustering techniques that suit the case-oriented approach in general, but the aim of examining types in particular. Three studies are included in the thesis. Financing of welfare states and redistribution strategies are examined in two broader studies including fifteen Western European countries. The third study is a more focused case study on welfare state adjustment in Finland and Sweden between 1990-98. The study concludes with four generalisations: Firstly, over the period examined the Nordic countries as a group had moved further away from the ideal typical picture of the Nordic welfare model. Secondly, in a relative comparison and in most of the areas examined the Nordic countries still clustered together and showed family resemblance. Thirdly, there were signs for convergence in several instances, although not to the extent to abolish diversity. Fourthly, these convergence processes meant that the distinctiveness of the Nordic countries by late-1990s was less evident than earlier.
  • Kautto, Mikko (2001)
    Tutkimus tarkastelee pohjoismaisten hyvinvointivaltioiden muutoksia länsi-eurooppalaisessa vertailussa keskittyen 1990-luvun tapahtumiin. Tutkimuksen teoreettinen tausta liittyy viimeaikaista vertailevaa hyvinvointivaltiotutkimusta ohjanneeseen vastakkainasetteluun. Valtaresurssiteorian ja siitä ammentavan hyvinvointiregiimi-näkökulman mukaan etenkin ideologiset ja poliittiset eroavuudet selittävät hyvinvointivaltioiden kehitystä ja hyvinvointivaltioiden välisiä 'laadullisia' eroja. Regiimiajattelun mukaan maiden kehitys on malli- tai polkuriippuvaa, ja siksi se näkee erojen säilyvän. Uusi konvergenssiteesi puolestaan haastaa tämän näkemyksen esittäessään, että 1990-luvun muuttuneissa oloissa ulkoiset syyt, ennen kaikkea globalisaatio ja Euroopan unionin toiminta, selittävät kehitystä ja johtavat hyvinvointivaltioiden välisten erojen supistumiseen. Molempien näkökulmien kannalta keskeinen empiirinen kysymys on missä määrin kansalliset sosiaali- ja yhteiskuntapolitiikan muutokset hämärtävät ns. hyvinvointivaltiomalleja erottavia rajoja. Typologioiden osuvuus ja pysyvyys ovat siten paitsi empiirisisesti myös teoreettisesti perusteltavissa olevia kysymyksiä. Tältä pohjalta tutkimuksessa asetetaan kaksi tutkimuskysymystä. Onko hyvinvointivaltioiden välillä systemaattisia eroja? Konvergoituvatko hyvinvointivaltiot? Tutkimuksen lähtökohtana käytetään ideaalityyppistä pohjoismaista mallia, jonka perusteella valitaan tarkasteltavat ulottuvuudet ja jota vasten arvioidaan muutosta. Pohjoismaisten hyvinvointivaltioiden muutosta tarkastellaan sekä yksittäisten piirteiden että piirteiden kokonaisuuden näkökulmasta. Tutkimuksen empiirisissä osissa tarkastellaan sosiaaliturvan rahoituksen ja sosiaalipolitiikan kehittymistä vertailukelpoisen tilastoaineiston, ennen kaikkea Eurostatin sosiaalimenotilastojen valossa. Menetelminä käytetään tilastollisia tunnuslukuja, taulukoita, graafisia menetelmiä sekä ryhmittelyanalyysiä, jotka soveltuvat tapauksien erojen ja yhtäläisyyksien sekä tyyppien arvioimiseen. Tutkimus sisältää kolme artikkelia. Ensimmäisessä vertaillaan sosiaaliturvan rahoitusta, toisessa uudelleenjaon strategioita (tulonsiirrot/palvelut). Molempiin vertailuihin on otettu 15 läntisen Euroopan maata (14 EU-maata ja Norja). Kolmas tutkimus tarkastelee lähemmässä vertailussa hyvinvointivaltion sopeuttamista Suomessa ja Ruotsissa vuosien 1990 ja 1998 välisenä aikana. Tutkimusten tulosten perusteella tehdään neljä loppupäätelmää. Ensinnäkin, tarkastelluilla ulottuvuuksilla ja ajanjaksolla pohjoismaat olivat ryhmänä siirtyneet kauemmaksi ideaalityyppisestä pohjoismaisesta mallista. Toiseksi, suhteellisessa vertailussa pohjoismaat erottuivat edelleenkin yhtenäisenä ryhmä. Kolmanneksi, tutkimus paikansi konvergenssikehitystä useilla ulottuvuuksilla, joskaan tämä kehitys ei poistanut maaryhmien välisiä eroja. Neljänneksi, konvergenssiprosessien seurauksena pohjoismaiden erilaisuus suhteessa muihin läntisen Euroopan maihin oli tarkastelluilla ulottuvuuksilla vähemmän selkeä kuin aikaisemmin.