935 resultados para Ultra som


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This is a study of ultra-cold Fermi gases in different systems. This thesis is focused on exotic superfluid states, for an example on the three component Fermi gas and the FFLO phase in optical lattices. In the two-components case, superfluidity is studied mainly in the case of the spin population imbalanced Fermi gases and the phase diagrams are calculated from the mean-field theory. Different methods to detect different phases in optical lattices are suggested. In the three-component case, we studied also the uniform gas and harmonically trapped system. In this case, the BCS theory is generalized to three-component gases. It is also discussed how to achieve the conditions to get an SU(3)-symmetric Hamiltonian in optical lattices. The thesis is divided in chapters as follows: Chapter 1 is an introduction to the field of cold quantum gases. In chapter 2 optical lattices and their experimental characteristics are discussed. Chapter 3 deals with two-components Fermi gases in optical lattices and the paired states in lattices. In chapter 4 three-component Fermi gases with and without a harmonic trap are explored, and the pairing mechanisms are studied. In this chapter, we also discuss three-component Fermi gases in optical lattices. Chapter 5 devoted to the higher order correlations, and what they can tell about the paired states. Chapter 6 concludes the thesis.

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Purpose: Mutations in IDH3B, an enzyme participating in the Krebs cycle, have recently been found to cause autosomal recessive retinitis pigmentosa (arRP). The MDH1 gene maps within the RP28 arRP linkage interval and encodes cytoplasmic malate dehydrogenase, an enzyme functionally related to IDH3B. As a proof of concept for candidate gene screening to be routinely performed by ultra high throughput sequencing (UHTs), we analyzed MDH1 in a patient from each of the two families described so far to show linkage between arRP and RP28. Methods: With genomic long-range PCR, we amplified all introns and exons of the MDH1 gene (23.4 kb). PCR products were then sequenced by short-read UHTs with no further processing. Computer-based mapping of the reads and mutation detection were performed by three independent software packages. Results: Despite the intrinsic complexity of human genome sequences, reads were easily mapped and analyzed, and all algorithms used provided the same results. The two patients were homozygous for all DNA variants identified in the region, which confirms previous linkage and homozygosity mapping results, but had different haplotypes, indicating genetic or allelic heterogeneity. None of the DNA changes detected could be associated with the disease. Conclusions: The MDH1 gene is not the cause of RP28-linked arRP. Our experimental strategy shows that long-range genomic PCR followed by UHTs provides an excellent system to perform a thorough screening of candidate genes for hereditary retinal degeneration.

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Reconfigurable antennas capable of radiating in only specific desired directions increase system functionality in applications like direction finding and beam steering. This paper presents the design simulation, fabrication and measurement of a horizontally polarized, direction reconfigurable Vivaldi antenna, designed for the lower-band UWB (2-6 GHz). This design employs eight circularly distributed independent Vivaldi antennas with a common port, electronically controlled by PIN diodes acting as RF switches. Experimental results show that the reconfigurable antenna has a bandwidth of 4 GHz (2-6 GHz), with 5 dB gain in the desired direction and capable of steering over the 360° range.

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The thesis The portrait interview as a newspaper genre. A qualitative close reading focussing on topical motifs, conventions of narration, and gender defines the portrait interview as a newspaper genre and analyses how the personalities in the portraits are constructed textually. The main body of material consists of 107 portrait interviews in two morning newspapers, Dagens Nyheter (published in Stockholm, Sweden) and Hufvudstadsbladet (published in Swedish in Helsinki, Finland), during two one-week periods (week 46/1999 and week 38/2002). There is also complementary material of 59 portraits from four magazines. The study is carried out within the research traditions of journalistic genre studies, gender and journalism, and critical text analysis. It is comprised of a qualitative close reading focussing on content (topical motifs or themes), conventions of narration, and gender. The methods used to carry out the study are qualitative close reading and quantitative content analysis. The analysis identifies the stylistic elements that differentiate the portrait genre from other journalistic genres, as well as from the autobiographical genre, and explores what opportunities and limitations these elements present for the inclusion of even more women protagonists in the portrait genre. The portrait interview is an exception from the critical mission of journalism in general, with its position as a genre of politeness. Since a typical characteristic of the portrait interview genre is that it pays tribute to the protagonist, the genre reveals the kind of personalities and lives that are seen as admirable in society. Four levels of portrait interview are defined: the prototype portrait, the pure portrait, the hybrid portrait and the marginal portrait. The prototype is a raw version of a portrait that fulfils the criteria but may be lacking in content and stylistics. The pure portrait does not lack these qualities and resembles an ideal portrait. The hybrid is a borderline case which relates to another genre or is a mixture between the portrait and some other genre, most commonly the news genre. The marginal portrait does not fulfil the criteria, and can therefore be seen as an inadequate portrait. For example, obituaries and caricatures are excluded if the protagonist s voice is never quoted. The analysis resulted in three factors that in part help to explain why the portrait interview genre has somewhat more female protagonists than journalistic news texts do in general. The four main reasons why women are presented somewhat more in the portrait genre than in other journalistic genres are: (i) women are shown as exceptions to the female norm when, for example, taking a typical male job or managing in positions where there are few women; (ii) women are shown as representing female themes ; (iii) use of the double bind as a story-generating factor; and (iv) the intimisation of journalism. The double bind usually builds up the narration on female ambiguity in the contradiction between private and public life, for example family and career, personal desire and work. The intimisation of journalism and the double bind give women protagonists somewhat more publicity also because of the tendency of portrait interviews to create conflicts within the protagonist, as an exception to journalism in general where conflicts are created or seen as existing between, for example, persons, groupings or parties. Women protagonists and their lives create an optimal narration of inner conflicts originating in the double bind as men are usually not seen as suffering from these conflicts. The analysis also resulted in gendered portrait norms: The feminine portrait norm and the masculine portrait norm or more concretely, professional life and family life as expectation and exception. Women are expected to be responsible parents and mediocre professionals, while men are expected to be professionals and in their free time engaging fathers. Key words: journalism, genre, portrait interview, gender, interview, newspaper, women s magazine.

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Purpose: Mutations in IDH3B, an enzyme participating in the Krebs cycle, have recently been found to cause autosomal recessive retinitis pigmentosa (arRP). The MDH1 gene maps within the RP28 arRP linkage interval and encodes cytoplasmic malate dehydrogenase, an enzyme functionally related to IDH3B. As a proof of concept for candidate gene screening to be routinely performed by ultra high throughput sequencing (UHTs), we analyzed MDH1 in a patient from each of the two families described so far to show linkage between arRP and RP28. Methods: With genomic long-range PCR, we amplified all introns and exons of the MDH1 gene (23.4 kb). PCR products were then sequenced by short-read UHTs with no further processing. Computer-based mapping of the reads and mutation detection were performed by three independent software packages. Results: Despite the intrinsic complexity of human genome sequences, reads were easily mapped and analyzed, and all algorithms used provided the same results. The two patients were homozygous for all DNA variants identified in the region, which confirms previous linkage and homozygosity mapping results, but had different haplotypes, indicating genetic or allelic heterogeneity. None of the DNA changes detected could be associated with the disease.

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Abstract (Irony as object of research: Is it possible to explore what is between the lines?): The main concern of this article is the interpretation of irony: how is it brought about and how can it be investigated? The method applied is based on authentic texts and their elicited interpretations − a method referred to in this article response analysis. Interpretation of irony in the approach taken is seen as being crucially dependent on the notion of coherence. A text is perceived as being coherent if it (a) makes sense and if it(b) hangs together. Incoherent texts can result in an ironic interpretation; however, the incoherence must also be perceived as being intentional, and intentionality in turn is a sign of the edge of the ironist. Ironic interpretation is defined as a combination of five factors: (1) an ironic edge that (2) reflects the intention of the ironist, and (3) has a target and (4) a victim too. Essential to irony is its fifth factor, the fact that one or more of these four factors must be inferred from co(n)text. This definition of irony is crucial in distinguishing irony from non-irony, and it also helps to discern the differences as well as the similarities between irony and related phenomena.

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Dimerization of thiolbenzoic acid has been studied by infra-red, ultra-violet and n.m.r. spectroscopy and cryoscopy. The results indicate that the tendency to form S - H. O hydrogen bonds is not appreciable.

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The ultraviolet bands of mercury iodide have been excited in uncondensed discharge and photographed with a quartz Littrow spectrograph. The bands in the region λ 2658 to 2530 Å have been analysed into two systems which may form the two components of a2Π-2∑ electronic transition with a2Π interval equal to 858·9 cm-1. These systems and the systems in the region λ 3095 to 2647 Å have the same lower state.

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Den klassiska situationen där konsumentinformationen på ett ensidigt sätt tidigare har levererats av företagen får ge vika för en ny situation där dagens konsument aktivt sprider information för att påverka andra konsumenters köpbeslut genom att prata med andra om köpupplevelser och specifika tjänsteleverantörer t ex genom diskussionsgrupper på Internet. För företagen är situationen kritisk då de håller på att mista sina maktmonopol på informationen. Innehållet i pratet är mycket viktigt för mottagarna av pratet eftersom de flesta kunder om de inte själva har upplevt företaget, skapar sina åsikter och förväntningar om företaget samt om dess varor och tjänster på basen av vad andra berättar om saken. Man kan då säga att pratet har fått en viktigare roll vid formandet av konsumtionsbeslutet. Syftet med denna studie är att skapa förståelse för vilka faktorer som initierar och påverkar prat hos kunder i långsiktiga relationer. På basis av de olika resultaten konstruerades en modell som förklarar sambandet mellan faktorerna. Modellens första del visar att prat initieras på basis av långvariga upplevelser i relationer mellan tjänsteleverantör och kund. Modellens andra del visar att pratet påverkas av kundens personliga karaktäristika och relationsrelaterade faktorer som upplevt engagemang i tjänstekategorin och i tjänsteleverantören samt i relationslängden. Modellens tredje del visar att kundernas prat varierar i aktivitet och omfång beroende på valensen av upplevelserna och beroende på om prataren har starka eller svaga band till pratmottagaren. Det är viktigt och mycket aktuellt att öka förståelsen för kunders kommunikationsbeteende ur ett relationsperspektiv. Ur företagsledningssynvinkel är det viktigt att förstå hur kunders prat påverkar utvecklingen av verksamhetsmiljön. Ur praktiskt tillämpningsperspektiv kan en ökad kunskap om pratet vidare hjälpa företaget att fokusera på vad kunderna anser vara viktigt i en relation. Genom att veta vad kunderna pratar om kan företaget förbättra svagheter i verksamheten, och därigenom minska på andelen negativt prat eller uppmuntra kunder att prata om fördelar som relationen med företaget ger åt kunden.