19 resultados para ALMOST-PERIODIC SOLUTIONS

em Helda - Digital Repository of University of Helsinki


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The aim of this research is to define what kind of characters and images of teachers appear in Finnish school novels describing social changes and educational political reform from the 1930s to the 1990s written by teachers, particularly grammar school teachers. As comparison material, I use school novels written by Swedish school teachers, in which the changes in Swedish society and educational system and their expressions in the characters of teachers of the school novels are studied. The main focus of my study is centred particularly on school novels in which the images of grammar school teachers are described during times of school reform. From these starting points, the main objectives of the study are novels written by Finnish school teachers Anneli Toijala and Sampo Haahtela and Swedish school teacher Hugo Swensson, who was inspired by Haahtela. The research is qualitative multidisciplinary case analysis. The research method is content analysis, and the approach is hermeneutic. The research is divided into eight main chapters. After the introduction I introduce the essential concepts of my research. In the third main chapter I define the research function. In that context, besides the research objectives, I introduce former research on character description in literature, I define the methodological solutions with grounds and present the research material. Both literary research methods and sociological terminology are applied in the research alongside with pedagogical research. The research results show that images of teachers are diverse. At one end of the spectrum these represent immature pictures of teachers withdrawn into the routines of everyday life; at the other, they advance and reflect the reformist teacher. This becomes clearly evident when comparing the teacher "monsters" of the classic authors to the educational optimists at the end of the 20th century. The results show that the images of teachers in school novels are almost without exception coherent, psychologically credible and consistent, and hardly any different from the images of teachers in the Swedish school novels used as comparison material. On the contrary, plenty of similarities are found. The comprehensive school reform, educational political discourse and teachers' feelings are realistically clarified in the school novels that describe the period. Keywords: literature image, school reform, school novel, teacher image, reflection, internal co-operation in school

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The molecular level structure of mixtures of water and alcohols is very complicated and has been under intense research in the recent past. Both experimental and computational methods have been used in the studies. One method for studying the intra- and intermolecular bindings in the mixtures is the use of the so called difference Compton profiles, which are a way to obtain information about changes in the electron wave functions. In the process of Compton scattering a photon scatters inelastically from an electron. The Compton profile that is obtained from the electron wave functions is directly proportional to the probability of photon scattering at a given energy to a given solid angle. In this work we develop a method to compute Compton profiles numerically for mixtures of liquids. In order to obtain the electronic wave functions necessary to calculate the Compton profiles we need some statistical information about atomic coordinates. Acquiring this using ab-initio molecular dynamics is beyond our computational capabilities and therefore we use classical molecular dynamics to model the movement of atoms in the mixture. We discuss the validity of the chosen method in view of the results obtained from the simulations. There are some difficulties in using classical molecular dynamics for the quantum mechanical calculations, but these can possibly be overcome by parameter tuning. According to the calculations clear differences can be seen in the Compton profiles of different mixtures. This prediction needs to be tested in experiments in order to find out whether the approximations made are valid.

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The importance of intermolecular interactions to chemistry, physics, and biology is difficult to overestimate. Without intermolecular forces, condensed phase matter could not form. The simplest way to categorize different types of intermolecular interactions is to describe them using van der Waals and hydrogen bonded (H-bonded) interactions. In the H-bond, the intermolecular interaction appears between a positively charged hydrogen atom and electronegative fragments and it originates from strong electrostatic interactions. H-bonding is important when considering the properties of condensed phase water and in many biological systems including the structure of DNA and proteins. Vibrational spectroscopy is a useful tool for studying complexes and the solvation of molecules. Vibrational frequency shift has been used to characterize complex formation. In an H-bonded system A∙∙∙H-X (A and X are acceptor and donor species, respectively), the vibrational frequency of the H-X stretching vibration usually decreases from its value in free H-X (red-shift). This frequency shift has been used as evidence for H-bond formation and the magnitude of the shift has been used as an indicator of the H-bonding strength. In contrast to this normal behavior are the blue-shifting H-bonds, in which the H-X vibrational frequency increases upon complex formation. In the last decade, there has been active discussion regarding these blue-shifting H-bonds. Noble-gases have been considered inert due to their limited reactivity with other elements. In the early 1930 s, Pauling predicted the stable noble-gas compounds XeF6 and KrF6. It was not until three decades later Neil Bartlett synthesized the first noble-gas compound, XePtF6, in 1962. A renaissance of noble-gas chemistry began in 1995 with the discovery of noble-gas hydride molecules at the University of Helsinki. The first hydrides were HXeCl, HXeBr, HXeI, HKrCl, and HXeH. These molecules have the general formula of HNgY, where H is a hydrogen atom, Ng is a noble-gas atom (Ar, Kr, or Xe), and Y is an electronegative fragment. At present, this class of molecules comprises 23 members including both inorganic and organic compounds. The first and only argon-containing neutral chemical compound HArF was synthesized in 2000 and its properties have since been investigated in a number of studies. A helium-containing chemical compound, HHeF, was predicted computationally, but its lifetime has been predicted to be severely limited by hydrogen tunneling. Helium and neon are the only elements in the periodic table that do not form neutral, ground state molecules. A noble-gas matrix is a useful medium in which to study unstable and reactive species including ions. A solvated proton forms a centrosymmetric NgHNg+ (Ng = Ar, Kr, and Xe) structure in a noble-gas matrix and this is probably the simplest example of a solvated proton. Interestingly, the hypothetical NeHNe+ cation is isoelectronic with the water-solvated proton H5O2+ (Zundel-ion). In addition to the NgHNg+ cations, the isoelectronic YHY- (Y = halogen atom or pseudohalogen fragment) anions have been studied with the matrix-isolation technique. These species have been known to exist in alkali metal salts (YHY)-M+ (M = alkali metal e.g. K or Na) for more than 80 years. Hydrated HF forms the FHF- structure in aqueous solutions, and these ions participate in several important chemical processes. In this thesis, studies of the intermolecular interactions of HNgY molecules and centrosymmetric ions with various species are presented. The HNgY complexes show unusual spectral features, e.g. large blue-shifts of the H-Ng stretching vibration upon complexation. It is suggested that the blue-shift is a normal effect for these molecules, and that originates from the enhanced (HNg)+Y- ion-pair character upon complexation. It is also found that the HNgY molecules are energetically stabilized in the complexed form, and this effect is computationally demonstrated for the HHeF molecule. The NgHNg+ and YHY- ions also show blue-shifts in their asymmetric stretching vibration upon complexation with nitrogen. Additionally, the matrix site structure and hindered rotation (libration) of the HNgY molecules were studied. The librational motion is a much-discussed solid state phenomenon, and the HNgY molecules embedded in noble-gas matrices are good model systems to study this effect. The formation mechanisms of the HNgY molecules and the decay mechanism of NgHNg+ cations are discussed. A new electron tunneling model for the decay of NgHNg+ absorptions in noble-gas matrices is proposed. Studies of the NgHNg+∙∙∙N2 complexes support this electron tunneling mechanism.

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It is well known that an integrable (in the sense of Arnold-Jost) Hamiltonian system gives rise to quasi-periodic motion with trajectories running on invariant tori. These tori foliate the whole phase space. If we perturb an integrable system, the Kolmogorow-Arnold-Moser (KAM) theorem states that, provided some non-degeneracy condition and that the perturbation is sufficiently small, most of the invariant tori carrying quasi-periodic motion persist, getting only slightly deformed. The measure of the persisting invariant tori is large together with the inverse of the size of the perturbation. In the first part of the thesis we shall use a Renormalization Group (RG) scheme in order to prove the classical KAM result in the case of a non analytic perturbation (the latter will only be assumed to have continuous derivatives up to a sufficiently large order). We shall proceed by solving a sequence of problems in which theperturbations are analytic approximations of the original one. We will finally show that the approximate solutions will converge to a differentiable solution of our original problem. In the second part we will use an RG scheme using continuous scales, so that instead of solving an iterative equation as in the classical RG KAM, we will end up solving a partial differential equation. This will allow us to reduce the complications of treating a sequence of iterative equations to the use of the Banach fixed point theorem in a suitable Banach space.

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Mobile RFID services for the Internet of Things can be created by using RFID as an enabling technology in mobile devices. Humans, devices, and things are the content providers and users of these services. Mobile RFID services can be either provided on mobile devices as stand-alone services or combined with end-to-end systems. When different service solution scenarios are considered, there are more than one possible architectural solution in the network, mobile, and back-end server areas. Combining the solutions wisely by applying the software architecture and engineering principles, a combined solution can be formulated for certain application specific use cases. This thesis illustrates these ideas. It also shows how generally the solutions can be used in real world use case scenarios. A case study is used to add further evidence.

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The systemic autoinflammatory disorders are a group of rare diseases characterized by periodically recurring episodes of acute inflammation and a rise in serum acute phase proteins, but with no signs of autoimmunity. At present eight hereditary syndromes are categorized as autoinflammatory, although the definition has also occasionally been extended to other inflammatory disorders, such as Crohn s disease. One of the autoinflammatory disorders is the autosomally dominantly inherited tumour necrosis factor receptor-associated periodic syndrome (TRAPS), which is caused by mutations in the gene encoding the tumour necrosis factor type 1 receptor (TNFRSF1A). In patients of Nordic descent, cases of TRAPS and of three other hereditary fevers, hyperimmunoglobulinemia D with periodic fever syndrome (HIDS), chronic infantile neurologic, cutaneous and articular syndrome (CINCA) and familial cold autoinflammatory syndrome (FCAS), have been reported, TRAPS being the most common of the four. Clinical characteristics of TRAPS are recurrent attacks of high spiking fever, associated with inflammation of serosal membranes and joints, myalgia, migratory rash and conjunctivitis or periorbital cellulitis. Systemic AA amyloidosis may occur as a sequel of the systemic inflammation. The aim of this study was to investigate the genetic background of hereditary periodically occurring fever syndromes in Finnish patients, to explore the reliability of determining serum concentrations of soluble TNFRSF1A and metalloproteinase-induced TNFRSF1A shedding as helpful tools in differential diagnostics, as well as to study intracellular NF-κB signalling in an attempt to widen the knowledge of the pathomechanisms underlying TRAPS. Genomic sequencing revealed two novel TNFRSF1A mutations, F112I and C73R, in two Finnish families. F112I was the first TNFRSF1A mutation to be reported in the third extracellular cysteine-rich domain of the gene and C73R was the third novel mutation to be reported in a Finnish family, with only one other TNFRSF1A mutation having been reported in the Nordic countries. We also presented a differential diagnostic problem in a TRAPS patient, emphasizing for the clinician the importance of differential diagnostic vigiliance in dealing with rare hereditary disorders. The underlying genetic disease of the patient both served as a misleading factor, which possibly postponed arrival at the correct diagnosis, but may also have predisposed to the pathologic condition, which led to a critical state of the patient. Using a method of flow cytometric analysis modified for the use on fresh whole blood, we studied intracellular signalling pathways in three Finnish TRAPS families with the F112I, C73R and the previously reported C88Y mutations. Evaluation of TNF-induced phosphorylation of NF-κB and p38, revealed low phosphorylation profiles in nine out of ten TRAPS patients in comparison to healthy control subjects. This study shows that TRAPS is a diagnostic possibility in patients of Nordic descent, with symptoms of periodically recurring fever and inflammation of the serosa and joints. In particular in the case of a family history of febrile episodes, the possibility of TRAPS should be considered, if an etiology of autoimmune or infectious nature is excluded. The discovery of three different mutations in a population as small as the Finnish, reinforces the notion that the extracellular domain of TNFRSF1A is prone to be mutated at the entire stretch of its cysteine-rich domains and not only at a limited number of sites, suggesting the absence of a founder effect in TRAPS. This study also demonstrates the challenges of clinical work in differentiating the symptoms of rare genetic disorders from those of other pathologic conditions and presents the possibility of an autoinflammatory disorder as being the underlying cause of severe clinical complications. Furthermore, functional studies of fresh blood leukocytes show that TRAPS is often associated with a low NF-κB and p38 phosphorylation profile, although low phosphorylation levels are not a requirement for the development of TRAPS. The aberrant signalling would suggest that the hyperinflammatory phenotype of TRAPS is the result of compensatory NF-κB-mediated regulatory mechanisms triggered by a deficiency of the innate immune response.

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Hydrophobins are a group of particularly surface active proteins. The surface activity is demonstrated in the ready adsorption of hydrophobins to hydrophobic/hydrophilic interfaces such as the air/water interface. Adsorbed hydrophobins self-assemble into ordered films, lower the surface tension of water, and stabilize air bubbles and foams. Hydrophobin proteins originate from filamentous fungi. In the fungi the adsorbed hydrophobin films enable the growth of fungal aerial structures, form protective coatings and mediate the attachment of fungi to solid surfaces. This thesis focuses on hydrophobins HFBI, HFBII, and HFBIII from a rot fungus Trichoderma reesei. The self-assembled hydrophobin films were studied both at the air/water interface and on a solid substrate. In particular, using grazing-incidence x-ray diffraction and reflectivity, it was possible to characterize the hydrophobin films directly at the air/water interface. The in situ experiments yielded information on the arrangement of the protein molecules in the films. All the T. reesei hydrophobins were shown to self-assemble into highly crystalline, hexagonally ordered rafts. The thicknesses of these two-dimensional protein crystals were below 30 Å. Similar films were also obtained on silicon substrates. The adsorption of the proteins is likely to be driven by the hydrophobic effect, but the self-assembly into ordered films involves also specific protein-protein interactions. The protein-protein interactions lead to differences in the arrangement of the molecules in the HFBI, HFBII, and HFBIII protein films, as seen in the grazing-incidence x-ray diffraction data. The protein-protein interactions were further probed in solution using small-angle x-ray scattering. Both HFBI and HFBII were shown to form mainly tetramers in aqueous solution. By modifying the solution conditions and thereby the interactions, it was shown that the association was due to the hydrophobic effect. The stable tetrameric assemblies could tolerate heating and changes in pH. The stability of the structure facilitates the persistence of these secreted proteins in the soil.

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The study analyses European social policy as a political project that proceeds under the guidance of the European Commission. In the name of modernisation, the project aims to build a new idea for the welfare state. To understand the project, it is necessary to distance oneself from both the juridical competence of the European Union and the traditional national welfare state models. The question is about sharing problems, as well as solutions to them: it is the creation and sharing of common views, concepts and images that play a key role in European integration. Drawing on texts and speeches produced by the European Commission, the study throws light on the development of European social policy during the first years of the 2000s. The study "freeze-frames" the welfare debate having its starting points in the nation states in the name of the entity of Europe. The first article approaches the European social model as a story in itself, a preparatory, persuasive narrative that concerns the management of change. The article shows how the audience can be motivated to work towards a set target by using discursive elements in a persuasive manner: the function of a persuasive story is to convince the target audience of the appropriateness of the chosen direction and to shape their identity so that they are favourably disposed to the desired political targets. This is a kind of "intermediate state" where the story, despite its inner contradictions and inaccuracies, succeeds in appearing as an almost self-evident path towards a modern social policy that Europe is currently seen to be in need of. The second article outlines the European social model as a question of governance. Health as a sector of social policy is detached from the old political order, which was based on the welfare state, and is closely linked to economy. At the same time the population is primarily seen as an economic resource. The Commission is working towards a "Europe of Health" that grapples with the problem of governance with the help of the "healthisation" of society, healthy citizenship and health economics. The way the Commission speaks is guided by the Union's powerful interest to act as "Europe" in the field of welfare policy. At the same time, the traditional separateness of health policy is effaced in order to be able to make health policy reforms a part of the Union's wider modernisation targets. The third article then shows the European social policy as its own area of governance. The article uses an approach based on critical discourse analysis in examining the classification systems and presentation styles adopted by Commission communications, as well as the identities that they help build. In analysing the "new start" of the Lisbon strategy from the perspective of social policy, the article shows how the emphasis has shifted from the persuasive arguments for change with necessary common European targets in the early stages of the strategy towards the implementation of reforms: from a narrative to a vision and from a diagnosis to healing. The phase of global competition represents "the modern" with which European society with its culture and ways of life now has to be matched. The Lisbon strategy is a way to direct this societal change, thus building a modern European social policy. The fourth article describes how the Commission uses its communications policy to build practices and techniques of governance and how it persuades citizens to participate in the creation of a European project of change. This also requires a new kind of agency: agents for whom accountability and responsibilities mean integration into and commitment to European society. Accountability is shaped into a decisive factor in implementing the European Union's strategy of change. As such it will displace hierarchical confrontations and emphasise common action with a view to modernising Europe. However, the Union's discourse cannot be described as being a political language that would genuinely rouse and convince the audience at the level of everyday life. Keywords: European social policy, EU policy, European social model, European Commission, modernisation of welfare, welfare state, communications, discoursiveness.