26 resultados para K MESONS

em Helda - Digital Repository of University of Helsinki


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We have measured the differential cross section for the inclusive production of psi(2S) mesons decaying to mu^{+} mu^{-1} that were produced in prompt or B-decay processes from ppbar collisions at 1.96 TeV. These measurements have been made using a data set from an integrated luminosity of 1.1 fb^{-1} collected by the CDF II detector at Fermilab. For events with transverse momentum p_{T} (psi(2S)) > 2 GeV/c and rapidity |y(psi(2S))| psi(2S)X) Br(psi(2S) -> mu^{+} mu^{-}) to be 3.29 +- 0.04(stat.) +- 0.32(syst.) nb.

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We have measured the differential cross section for the inclusive production of psi(2S) mesons decaying to mu^{+} mu^{-1} that were produced in prompt or B-decay processes from ppbar collisions at 1.96 TeV. These measurements have been made using a data set from an integrated luminosity of 1.1 fb^{-1} collected by the CDF II detector at Fermilab. For events with transverse momentum p_{T} (psi(2S)) > 2 GeV/c and rapidity |y(psi(2S))| psi(2S)X) Br(psi(2S) -> mu^{+} mu^{-}) to be 3.29 +- 0.04(stat.) +- 0.32(syst.) nb.

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We report a search for narrow resonances, produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV, that decay into muon pairs with invariant mass between 6.3 and 9.0 GeV/c^2. The data, collected with the CDF~II detector at the Fermilab Tevatron collider, correspond to an integrated luminosity of 630 pb$^{-1}$. We use the dimuon invariant mass distribution to set 90% upper credible limits of about 1% to the ratio of the production cross section times muonic branching fraction of possible narrow resonances to that of the $\Upsilon(1{\rm S})$ meson.

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The subject of this work is the poetics of «The Wax Effigy», a short novel or novella by Jurii Tynianov, Russian writer, literary critic, historian of literature and prominent literary theoretician. The plot structure of the novel is based upon a real event, the creation by Bartolomeo Carlo Rastrelli in 1725 of a wax sculpture of the first Russian emperor, Peter the Great. «Construction of the Sham» consists of three chapters, an introduction and a conclusion. Due to the fact that Tynianov was at the same time a prose writer and theoretician of literature it seemed important to consider the reception of his prose and his works on literary theory in relationship to each other. The introduction is devoted to this task. The first chapter is about the history of the creation of the novel and its reception. Tynianov stopped writing one short story in order to write the novel; these two works have some common traits. It seems almost obvious that his work on the first text was a real step toward the creation of the second. In the first story there is an opposition of dead/alive which is semantic prefiguring of a central motif in «The Wax Effigy». An analysis of the reception of the novel demonstrated that almost every critic writing about the novel has described it as nonsense. Critics considered Tynianov's work in terms of «devices» and «content» and could not understand how devices are related to the content of the novel: the novel was thought as a signifier without any signified. Implicitly, critics thought the signified of the novel as a traditional one of the historical novel, as the historiosophical «idea», embodied in the system of literary devices. In this case literature becomes something instrumental, a kind of expression of extraliterary content. In contradistinction to that Tynianov considered literary semantics as an effect of the literary structure. From his point of view the literary sense is immanent to the process of signification accomplished inside the literary text. The second chapter is devoted to a rhetorical analysis of the opposition dead/alive. Tynianov systematically compares both terms of the opposition. As a result of this strategy the wax effigy of the dead emperor becomes «as if» alive and the world of living people «as if» dead. The qualifier «as if» refers to the fact that Tynianov creates an ambiguous semantic system. This rhetoric is related to European Romanticism and his «fantastic literature» (Merimé, Hoffmann, Maupassant etc.). But Tynianov demonstrates a linguistic origin of the strange fantoms created by romantics; he demystifies these idols by parodying the fantastic literature, that is, showing «how it was done». At the same time, the opposition mentioned above refers to his idea of «incongruity» which plays a prominent role in Tynianov s theory but has never been conceptualised. The incongruity is a inner collision of the literary text; from Tynianov's point of view the meaning of the work of literature is always a dynamic collision of semantically heterogeneous elements struggling with each other. In «The Wax Effigy» Tynianov creates a metalevel of the work demonstrating the process of creation of the literary sense. The third chapter is a reconstruction of Tynianov's conception of the historical prose, specifically of the mechanisms by which historical facts are transformed into literary events. Tynianov thought that the task of the historical novelist is to depict his hero as an actor, to demonstrate that as a wearer of many masks he is a creator of appearances, ambiguities. Here, in the «figure of fiction» (Andrei Belyi), the very idea of the historical prose and rhetoric employed in «The Wax Effigy», history and literature meet each other. In his last theoretical work, «On parody» Tynianov writes about the so-called sham structure of parody. In his opinion every parody is a text about other texts and «serious» work which could be read at the same time as a text about «reality». This twofold structure of parody is that of «The Wax Effigy»: that text speaks about ambiguities of the history and about ambiguities of the literary sense, about social reality of the past and - about the working of the literature itself. «The Wax Effigy» is written as a autoreflective text, as an experiment in literary semantics, as a system of literary ambiguities - of hero, rhetoric and the text itself. The meaning of the novel is created not by the embodiment extraliterary idea, but by the process of signification accomplished inside the work of literature. In this sense Tynianov's novel is parody, a break with the tradition of the historical novel preceding «The Wax Effigy».

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The dissertation deals with the prose texts of the Finnish writer Timo K. Mukka, renowned for his depictions of his native Lapland. This research concerns the creation of world view in Mukka s prose, which is approached by studying what Mikhail Bakhtin calls generic change. Such genre change is the most characteristic feature of Mukka s prose. His prose is permeated with two genres in particular and changes between them: the ballad-like, archaistic and romantic prose-poem style and naturalistic, even grotesque expressions. In addition, these genres are associated with sublime and grotesque styles so that generic change tends to involve also stylistic changes in Mukka s prose. This study probes the tension-filled interrelationships between the ballad and naturalistic prose by examining the discourse of Mukka s characters. It is shown that these characters invariably find themselves in what Bakhtin calls the chronotope of the threshold; that is, the plots of Mukka s novels and short stories depict situations in which the characters are faced with decisions and deeds that will profoundly impact their lives. The discourse of the threshold affects the characters speech by filling it with dialogical dimensions. This makes their communication ethically loaded and polyphonic. This study is based on Mikhail Bakhtin s theory of the novel and international Bakhtin s studies. I also take into consideration the theoretical developments of Bakhtin s work; for example, the concept of ressentiment, adapted from the Bakhtin scholar Michel André Bernstein, plays an important role. In order to explicate on the psychology of Mukka s characters such as melancholy, abjection, sadism, and taboo I use the concepts familiar from Freudian psychoanalysis. The corpus of my research consists of the following texts: the long prose texts Maa on syntinen laulu. Balladi (1964), Tabu (1965), Täältä jostakin. Romaani (1965), Laulu Sipirjan lapsista. Romaani (1966), Ja kesän heinä kuolee. Kertomus sairaudesta (1968) ja Kyyhky ja unikko (1970) and the short story collections Koiran kuolema (1967) ja Lumen pelko (1970), and with Tabu published short story Sankarihymni , the short story Katkelma laajemmasta laulelmasta from the collection Rakastaa: Kaksitoista novellia rakkaudesta (1965) and also the short stories which were published in various Finnish journals: YÃt (1965), Liisa (1967), Tyttà (1967) ja Näin hetki sitten ketun (1970). I pay particular attention to the novel Maa on syntinen laulu, because it expresses the generic change characteristic of Mukka s world view in a specifically clear and lively way. The dissertation is in Finnish. Key words: Timo K. Mukka, world view, genre change, ballad, naturalism, grotesque realism, Mikhail Bakhtin, dialogism, polyphony, chronotope, sublime, grotesque, ressentiment, Sigmund Freud, melancholy, taboo, abject, sadism, reduced laughter, modern parody.

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I denna avhandling undersÃker jag hur modersmÃ¥lslärare inom den grundläggande utbildningen (Ã¥k 7â9) undervisar i litteratur. De frÃ¥gor jag ställer mig är: Hur fÃrverkligar lärarna sin litteraturundervisning i praktiken, hur fÃrhÃ¥ller de sig till den nya läroplanen i ämnet, Grunderna fÃr läroplanen fÃr den grundläggande utbildningen 2004, samt med vilken ämnes-, litteratur- och kunskapssyn utgÃ¥r de frÃ¥n i sin undervisning? UndersÃkningsresultatet analyseras utifrÃ¥n läroplan och utifrÃ¥n en läsarorienterad, sociokulturell och funktionell litteratursyn och litteraturpedagogik. UndersÃkningen är kvalitativ och riktar sig i form av ett frÃ¥geformulär till alla modersmÃ¥lslärare i hÃgstadierna i huvudstadsregionen. Tretton lärare deltar slutligen och Ã¥tta av dessa svar uppfÃljs genom en tematisk intervju. UndersÃkningen sker vÃ¥ren 2005. Forskningsresultatet visar pÃ¥ att flera av lärarna till stor del bygger upp sin undervisning utifrÃ¥n färdiga uppgifter och koncept och att undervisningen styrs av metoden, av frÃ¥gan hur. Dessa lärares undervisning sker sÃ¥ledes inte utgÃ¥ende frÃ¥n en enhetlig ämnes-, litteratur- och kunskapssyn, utan ämnessynen varierar beroende pÃ¥ uppgift. Recensionen är den arbetsuppgift som är vanligast bland lärarna, även om flera lärare ställer sig tveksamma till den. Ãvriga uppgifter som fÃrekommer bland flera lärare är uppgiftskoncept kring klassiker och litterära samtal infÃr klass. Tematisk litteraturundervisning används även av flera lärare, liksom Netlibris, som innebär att tvÃ¥ klasser frÃ¥n olika skolor Ãver nätet diskuterar en skÃnlitterär text. BÃ¥de Netlibris och tematisk litteraturundervisning är metoder som lärarna fÃrhÃ¥ller sig positiva till och ser pedagogiska fÃrdelar med. Den tematiska undervisningen sker emellertid ofta i form av koncept som Ã¥terkommer i samma form Ã¥r efter Ã¥r. TvÃ¥ lärare strävar dock efter att arbeta utifrÃ¥n en enhetlig ämnessyn â den erfarenhetspedagogiska. Dessa lärare använder sig av färre koncept i sin undervisning. De bygger snarare upp sin undervisning utifrÃ¥n frÃ¥gan varfÃr än hur, vilket innebär att de i hÃgre grad har mÃjlighet att beakta elevernas intressen och behov i utformandet av undervisningen. Detta syns bland annat i valet av bÃcker och teman. En av dessa lärare använder sig även av portfÃlj- och loggboksmetodik och lÃ¥ter, i enlighet med läroplanen, eleverna själva vara med och utvärdera undervisningen och den egna utvecklingen. Lärarna verkar Ãverlag fÃrhÃ¥lla sig mera positiva till de uppgifter som bygger pÃ¥ dialog och som tar fasta pÃ¥ läsaren i läsprocessen. Trots att lärarna betonar dialogens betydelse i litteraturundervisningen, bygger undervisningen ändÃ¥ ofta, och i flera fall helt och hÃ¥llet, pÃ¥ uppgifter som saknar dialog. En av orsakerna till detta kan vara att gamla koncept, trots nya uppgifter, lever kvar i undervisningen. Att lärarna framhÃ¥ller de uppgifter som utgÃ¥r frÃ¥n läsning av gemensamma texter och som tar fasta pÃ¥ en läsarorienterad och sociokulturell litteratursyn, visar dock pÃ¥ att de nya uppgifterna hÃ¥ller pÃ¥ att omkullkasta de gamla; lärarnas litteraturundervisning befinner sig sÃ¥ledes i fÃrändring. Samtliga lärare fÃrhÃ¥ller sig positiva till litteraturundervisning och framhÃ¥ller att litteraturen sedan deras egen skoltid fÃ¥tt en mera framträdande roll i undervisningen. De pÃ¥pekar ocksÃ¥ att modersmÃ¥lsundervisningen idag är mindre färdighetsinriktad och gÃ¥r mot en Ãkad dialog.

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Individuality and the Community in the Development of K. E. Nipkow's Theory of Religious Education from 1960 to 1990 The purpose of this study was to describe and analyze the development occurred between 1960 and 1990 of the theory of religious education as proposed by K. E. Nipkow, the German Religious Education specialist, from the point of view of individuality and the community. Nipkow's methodological approach of dialectic convergence theory resulted in a dialogue between theological and educational factors, which supported the thirty-year development of Nipkow's models, theoretical foundations, and theory of religious education. Nipkow's doctoral dissertation, published in 1960, deals with individuality in the thinking of Pestalozzi, Humboldt and Schleiermacher. Nipkow regarded individuality as one of the basic concepts of education, which were to be interpreted anew as social and historical situations changed. In the late 1960s Nipkow developed the so-called experiential hermeneutically oriented context model for the needs of religious education. In this model, individuality is expressed in the attention paid to pupils' life situations and the educational reality. The multi-dimensional theoretical framework of religious education in 1975 emphasized supporting identity as a fundamental task of religious education. The concept of individuality was thus given a new form, in accordance with contemporary theories of developmental psychology. Other fundamental tasks, such as the socio-ethical task, the task of critical religious thinking, and that of ecumenical learning, meant a more specific emphasis on the community. It was an outline of a liberating education, which faced the individualistic-existential and social-ecclesiastical challenges of the time with a critical attitude. The further development of the theoretical outline in 1982 continued to uphold the perspectives of both individuality and the community, as Nipkow combined a historical-social dimension with theories of developmental psychology, especially that of life-span research. According to him, the development of the individual and communal life-reality belonged together. The fundamental task of religious education came to be learning to live and believe together. Nipkow transferred the idea of dialogue into inter-generational learning and developed elementarization as a methodology of Religious Education, which takes into account the point of departure of each age group. His theory of educational responsibility in the church (1990) contained the tasks of walking alongside the individual and the renewal of church communities as prerequisites of communicating the Christian faith in an era characterized by multifaceted Christianity. The "geisteswissenschaftliche" school and its concepts (Ger. Individualität; Bildung) were found to be the explanatory factor of the concepts of individuality and the community in the development of Nipkow's theory of religious education. The concept of education employed by Nipkow (Ger. Bildung) implies, on one hand, the individuality, autonomy, freedom and personal responsibility of people of different ages, and on the other hand, the dialogical nature of education in the community facilitated by this concept. Theologically, Nipkow associates himself in his views on individuality and the community with Schleiermacher's understanding of faith, of which openness towards the world was characteristic. The significance of individuality and the community in Nipkow's thinking was, furthermore, deepened by his participation, as a member of working parties, in the educational discussions of the World Council of Churches.

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K-Cl cotransporter 2 (KCC2) maintains a low intracellular Cl concentration required for fast hyperpolarizing responses of neurons to classical inhibitory neurotransmitters γ-aminobutyric acid (GABA) and glycine. Decreased Cl extrusion observed in genetically modified KCC2-deficient mice leads to depolarizing GABA responses, impaired brain inhibition, and as a consequence to epileptic seizures. Identification of mechanisms regulating activity of the SLC12A5 gene, which encodes the KCC2 cotransporter, in normal and pathological conditions is, thus, of extreme importance. Multiple reports have previously elucidated in details a spatio-temporal pattern of KCC2 expression. Among the characteristic features are an exclusive neuronal specificity, a dramatic upregulation during embryonic and early postnatal development, and a significant downregulation by neuronal trauma. Numerous studies confirmed these expressional features, however transcriptional mechanisms predetermining the SLC12A5 gene behaviour are still unknown. The aim of the presented thesis is to recognize such transcriptional mechanisms and, on their basis, to create a transcriptional model that would explain the established SLC12A5 gene behaviour. Up to recently, only one KCC2 transcript has been thought to exist. A particular novelty of the presented work is the identification of two SLC12A5 gene promoters (SLC12A5-1a and SLC12A5-1b) that produce at least two KCC2 isoforms (KCC2a and KCC2b) differing by their N-terminal parts. Even though a functional 86Rb+ assay reveals no significant difference between transport activities of the isoforms, consensus sites for several protein kinases, found in KCC2a but not in KCC2b, imply a distinct kinetic regulation. As a logical continuation, the current work presents a detailed analysis of the KCC2a and KCC2b expression patterns. This analysis shows an exclusively neuron-specific pattern and similar expression levels for both isoforms during embryonic and neonatal development in rodents. During subsequent postnatal development, the KCC2b expression dramatically increases, while KCC2a expression, depending on central nervous system (CNS) area, either remains at the same level or moderately decreases. In an attempt to explain both the neuronal specificity and the distinct expressional kinetics of the KCC2a and KCC2b isoforms during postnatal development, the corresponding SLC12A5-1a and SLC12A5-1b promoters have been subjected to a comprehensive bioinformatical analysis. Binding sites of several transcription factors (TFs), conserved in the mammalian SLC12A5 gene orthologs, have been identified that might shed light on the observed behaviour of the SLC12A5 gene. Possible roles of these TFs in the regulating of the SLC12A5 gene expression have been elucidated in subsequent experiments and are discussed in the current thesis.

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Several excited states of Ds and Bs mesons have been discovered in the last six years: BaBar, Cleo and Belle discovered the very narrow states D(s0)*(2317)+- and D(s1)(2460)+- in 2003, and CDF and DO Collaborations reported the observation of two narrow Bs resonances, B(s1)(5830)0 and B*(s2)(5840)0 in 2007. To keep up with experiment, meson excited states should be studied from the theoretical aspect as well. The theory that describes the interaction between quarks and gluons is quantum chromodynamics (QCD). In this thesis the properties of the meson states are studied using the discretized version of the theory - lattice QCD. This allows us to perform QCD calculations from first principles, and "measure" not just energies but also the radial distributions of the states on the lattice. This gives valuable theoretical information on the excited states, as we can extract the energy spectrum of a static-light meson up to D wave states (states with orbital angular momentum L=2). We are thus able to predict where some of the excited meson states should lie. We also pay special attention to the order of the states, to detect possible inverted spin multiplets in the meson spectrum, as predicted by H. Schnitzer in 1978. This inversion is connected to the confining potential of the strong interaction. The lattice simulations can also help us understand the strong interaction better, as the lattice data can be treated as "experimental" data and used in testing potential models. In this thesis an attempt is made to explain the energies and radial distributions in terms of a potential model based on a one-body Dirac equation. The aim is to get more information about the nature of the confining potential, as well as to test how well the one-gluon exchange potential explains the short range part of the interaction.

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The analysis uses data from an integrated luminosity of approximately 172 pb-1 of ppbar collisions at sqrt(s)=1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. The Lambda_b and B0 relative branching fractions are measured to be: B(Lambda_b to Lambda_c+ mu nu)/B(Lambda_b to Lambda_c+ pi) = 16.6 +- 3.0 (stat) +- 1.0 (syst) +2.6 -3.4 (PDG) +- 0.3 (EBR), B(B0 to D+ mu nu)/B(B0 to D+ pi) = 9.9 +- 1.0 (stat) +- 0.6 (syst) +- 0.4 (PDG) +- 0.5 (EBR), B(B0 to D*+ mu nu)/B(B0 to D*+ pi) = 16.5 +- 2.3 (stat) +- 0.6 (syst) +- 0.5 (PDG) +- 0.8 (EBR) This article also presents measurements of the branching fractions of four new Lambda_b semileptonic decays: Lambda_b to Lambda_c(2595)+ mu nu, Lambda_b to Lambda_c(2625)+ mu nu, Lambda_b to Sigma_c(2455)0 pi mu nu, Lambda_b to Sigma_c(2455)++ pi mu nu, relative to the branching fraction of the Lambda_b to Lambda_c mu nu decay. Finally, the transverse-momentum distribution of Lambda_b baryons produced in p-pbar collisions is measured and found to be significantly different from that of B0 mesons.

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A combined mass and particle identification fit is used to make the first observation of the decay Bs --> Ds K and measure the branching fraction of Bs --> Ds K relative to Bs --> Ds pi. This analysis uses 1.2 fb^-1 integrated luminosity of pbar-p collisions at sqrt(s) = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron collider. We observe a Bs --> Ds K signal with a statistical significance of 8.1 sigma and measure Br(Bs --> Ds K)/Br(Bs --> Ds pi) = 0.097 +- 0.018(stat) +- 0.009(sys).

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We search for b to s\mu^+\mu^- transitions in B meson (B^+, B^0, or B^0_s) decays with 924pb^{-1} of p pbar collisions at sqrt(s)=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We find excesses with significances of 4.5, 2.9, and 2.4 standard deviations in the B^+ to \mu^+\mu^-K^+, B^0 to \mu^+\mu^-K^*(892)^0, and B_s^0 to \mu^+\mu^-\phi decay modes, respectively. Using B to J/psi h (h = K^+, K^*(892)^0, phi) decays as normalization channels, we report branching fractions for the previously observed B^+ and B^0 decays, BR(B^+ to \mu^+\mu^-K^+)=(0.59\pm0.15\pm0.04) x 10^{-6}, and BR(B^0 to \mu^+\mu^-K^*(892)^0)=(0.81\pm0.30\pm0.10) x 10^{-6}, where the first uncertainty is statistical, and the second is systematic. These measurements are consistent with the world average results, and are competitive with the best available measurements. We set an upper limit on the relative branching fraction BR(B_s^0 to \mu^+\mu^-\phi)/BR(B_s^0 to J/\psi\phi)