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Enkätstudie om gymnasieungdomars attityder till stark musik / Questionnaire study on adolescents attitudes towards loud musicLandälv, Daniel, Malmström, Lennart January 2011 (has links)
Bakgrund: Tinnitus och ljudkänslighet är symptom som tycks öka bland ungdomar. En förklaring kan vara att ungdomar tillbringar allt mer och längre tid i bullriga miljöer utan att använda hörselskydd. Syfte: Syftet med studien är att jämföra gymnasieungdomars attityder till stark musik i relation till olika självupplevda hörselsymptom samt med avseende på variablerna norm, risktagande och riskmedvetenhet. Metod: Enkätstudie på 281 gymnasieungdomar i åldrarna 15-19 år, om deras attityder till stark musik. Enkäten bygger bl.a. på frågor och påståenden från Youth Attitude to Noise Scale, Health Belief Model och Theory of Planned Behavior. Resultat: Personer med permanent tinnitus hade mer negativa attityder till stark musik än de som inte hade det. Även självupplevda hörselsymptom relaterade till ljudkänslighet hade ett signifikant samband med mer negativa attityder till stark musik. Tillsammans förklarar de oberoende variablerna permanent tinnitus och frågorna om ljudkänslighet 17,4% av variationen i attityder till stark musik. De psykologiska variablerna norm, riskmedvetenhet och risktagande förklarade 40,8% av variationen i attityder till stark musik. Tillsammans med hörselsymptomsvariablerna permanent tinnitus och ljudkänslighet förklarades 48,0% av variationen i attityder. Slutsatser: De psykologiska variablerna i vår undersökning förklarar mer av ungdomarnas attityder till stark musik än vad de självupplevda hörselsymptomen gör.
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Mångfald eller företagskultur : En fallstudie om den pratadoxala relationen kring mångfald och företagskulturDanielsson, Linn, Olofsson, Alexander January 2012 (has links)
ABSTRACT Course/level: Enterprising and Business Development, Bachelor Thesis, AUT2012, 2EB00E Tutor: Magnus Forslund Authors: Linn Danielsson & Alexander Olofsson Key words: Strong diversity, Consistent Corporate Culture, Core Values, Corporate Strategy, Definition of Diversity, Working with Diversity, Management, Standardization. Title: Diversity or Corporate Culture – A case study on the paradoxical relationship between diversity and corporate cultures in corporations and organizations. Background: Diversity and corporate culture can in various ways result in corporate and organizational advantages. While diversity promotes innovation, creativity and company development corporate culture possesses advantages such as efficiency, community and unity. Diversity and corporate culture seems to create various benefits that are both beneficial for competitive advantage. Problem discussion: I would be beneficial for companies and organizations to maintain both diversity and corporate culture since they complement each other. However, diversity and corporate culture have different purposes and benefit in different ways. The question is how two such different strategies can meet. Question for research: How does diversity and corporate culture co-exist in corporations and organizations? Purpose: The aim of this study is to create further understanding for the co-existence between diversity and corporate culture in corporations and organizations. Method: The study is made qualitatively with a hermeneutic approach and based on a case study on two corporations within the real estate industry. Data has been gathered through semi structured interviews, governing documents, diversity plans and policies combined with theory. Results: The study shows that diversity and corporate culture to some extent co-exist within corporations and organizations. Strong diversity and strong corporate culture cannot fully coexist due to the conflict between strong diversity and strong corporate culture. The study shows that corporate culture is dominant and diversity will only be allowed in controlled forms. / SAMMANFATTNING Kurs/nivå: Enterprising and business development, Kandidatuppsats, C-nivå, VT2012, 2EB00E Handledare: Magnus Forslund Författare: Linn Danielsson & Alexander Olofsson Nyckelord: Stark mångfald, Konsistent företagskultur, Värdegrund, Företagsstrategi, Mångfaldsdefinition, Mångfaldsarbete, Ledning, Standardisering. Titel: Mångfald eller företagskultur – en fallstudie om den paradoxala relationen kring mångfald och företagskultur i företag och organisationer Bakgrund: Mångfald och företagskultur kan på olika sätt bidra med fördelar i företag och organisationer. Medan mångfald verkar för innovation, kreativitet och utveckling besitter företagskulturen fördelar såsom effektivitet, gemenskap och enhetlighet. Mångfald och företagskultur tycks därmed skapa olika fördelar som båda är fördelaktiga för konkurrenskraftighet. Problemdiskussion: Fördelaktigt vore om företag och organisationer kunde tillvarata både mångfaldens och företagskulturens fördelar för att komplettera varandra. Dock tycks mångfald och företagskultur ha olika syften och främjas på olika sätt. Frågan är hur två sådana olika strategier kan mötas. Forskningsfråga : Hur samexisterar mångfald och företagskultur i företag och organisationer? Syfte : Studien syftar till att skapa förståelse för samexistensen mellan mångfald och företagskultur i företag och organisationer. Metod : Studien är kvalitativ utifrån ett hermeneutiskt förhållningssätt och baseras på en fallstudie på två företag inom fastighetsbranschen. Data har främst insamlats genom semistrukturerade intervjuer, styrdokument, mångfaldsplan och policy tillsammans med teori Resultat : Studien visar att mångfald och företagskultur kan samexistera till viss del i en organisation men de kan inte nå en full samexistens då det finns en konflikt mellan en stark mångfald och en stark företagskultur. Det är mångfalden som begränsas utifrån en starkare företagskultur.
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Progress towards directly measuring the membrane dipole field in lipid bicelles using vibrational Stark effect spectroscopyHu, Wenhui, M.A. 16 February 2012 (has links)
The electrostatic field created by the inward pointing dipole moments of an oriented membrane leaflet has never been measured directly, but is thought to have an important influence on membrane function. Here we present the first direct measurement of the membrane dipole field in lipid bicelles using vibrational Stark effect spectroscopy which is based on the sensitivity of a nitrile oscillator’s vibrational frequency to its local electrostatic environment. The nitrile probe was introduced as the artificial amino acid p-cyanophenylalanine (CN-Phe) in four different locations of a α-helical peptide composed of alternating alanine and leucine residues. This peptide was intercalated into bicelles composed of mixtures of the long chain lipids 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), or 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and the short chain lipid 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) formed in two different sizes, 5 nm and 15 nm in radius. Formation of the bicelle above the phase transition temperature of the lipid mixture was confirmed by ³¹P NMR, and the structure of the [alpha]-helix within the bicelle was confirmed by circular dichroic spectroscopy. The absorption energy of the nitrile probe at 4 positions along the helical axis was measured by Fourier transform infrared spectroscopy, from which we estimate the magnitude of the membrane dipole electrostatic field to be -6 MV/cm. Then we successfully manipulated the dipole field in q = 0.5 DMPC/DHPC bicelles by incorporating the small molecule phloretin into the membrane and measured the corresponding ratiometric fluorescence signal of the co-intercalated voltage gated dye di-8-ANEPPS. We measured 0.7 ± 0.2 cm⁻¹ blue shift in absorption energy of the nitrile probe due to the decrease in dipole field caused by phloretin, corresponding to a dipole field of -4.2 MV/cm. This change was essentially identical to what has been estimated through ratiometric fluorescence methods, indicating that VSE spectroscopy will be useful tool for measurement of the biological effects of electrostatic fields in lipid membranes. / text
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Electrostatic fields at the functional interface of the protein Ral guanine nucleotide dissociation stimulator determined by vibrational Stark effect spectroscopyStafford, Amy Jo 16 February 2012 (has links)
Noncovalent factors, such as shape complementarity and electrostatic driving forces, almost exclusively cause the affinity and specificity for which two or more biological macromolecules organize into a functioning complex. The human oncoprotein p21Ras (Ras) and a structurally identical but functionally distant analog, Rap1A (Rap), exhibit high selectivity and specificity when binding to downstream effector proteins that cannot be explained through structural analysis alone. Both Ras and Rap bind to Ral guanine nucleotide dissociation stimulator (RalGDS) with affinities that differ tenfold instigating diverse cellular functions; it is hypothesized that this specificity of RalGDS to discriminate between GTPases is largely electrostatic in nature. To investigate this hypothesis, electrostatic fields at the binding interface between mutants of RalGDS bound to Rap or Ras are measured using vibrational Stark effect (VSE) spectroscopy, in which spectral shifts of a probe oscillator’s energy is related directly to that probe’s local electrostatic environment and measured by Fourier transform infrared spectroscopy (FTIR). After calibration, the probe is inserted into a known position in RalGDS where it becomes a highly local, sensitive, and directional reporter of fluctuations of the protein’s electrostatic field caused by structural or chemical perturbations of the protein. The thiocyanate (SCN) vibrational spectroscopic probe was systematically incorporated throughout the binding interface of RalGDS. Changes in the absorption energy of the thiocyanate probe upon binding were directly related to the change of the strength of the local electrostatic field in the immediate vicinity of the probe, thereby creating a comprehensive library of the binding interactions between Ras-RalGDS and Rap-RalGDS. The measured SCN absorption energy on the monomeric protein was compared with solvent-accessible surface area (SASA) calculations with the results highlighting the complex structural and electrostatic nature of protein-water interface. Additional SASA studies of the nine RalGDS mutants that bind to Ras or Rap verified that experimentally measured thiocyanate absorption energies are negatively correlated with exposure to water at the protein-water interface. By changing the solvent composition, we confirmed that the cyanocysteine residues that are more exposed to solvent experienced a large difference in absorption energy. These studies reinforce the hypothesis that differences in the electrostatic environment at the binding interfaces of Ras and Rap are responsible for discriminating binding partners. / text
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Quantifying electrostatic fields at protein interfaces using classical electrostatics calculationsRitchie, Andrew William 17 September 2015 (has links)
The functional aspects of proteins are largely dictated by highly selective protein- protein and protein-ligand interactions, even in situations of high structural homology, where electrostatic factors are the major contributors to selectivity. The vibrational Stark effect (VSE) allows us to measure electrostatic fields in complex environments, such as proteins, by the introduction of a vibrational chromophore whose vibrational absorption energy is linearly sensitive to changes in the local electrostatic field. The works presented here seek to computationally quantify electrostatic fields measured via VSE, with the eventual goal of being able to quantitatively predict electrostatic fields, and therefore Stark shifts, for any given protein-interaction. This is done using extensive molecular dynamics in the Amber03 and AMOEBA force fields to generate large ensembles the GTPase Rap1a docked to RalGDS and [superscript p]²¹Ras docked to RalGDS. We discuss how side chain orientations contribute to the differential binding of different mutations of Rap1a binding to RalGDS, where it was found that a hydrogen-bonding pocket is disrupted by the mutation of position 31 from lysine to glutamic acid. We then show that multi-dimensional umbrella sampling of the probe orientations yields a wider range of accessible structures, increasing the quality of the ensembles generated. A large variety of methods for calculating electrostatic fields are presented, with Poisson- Boltzmann electrostatics yielding the most consistent, reliable results. Finally, we explore using AMOEBA for both ensemble-generation as well as the electrostatic description of atoms for field calculations, where early results suggest that the electrostatic field due to the induce dipole moment of the probe is responsible for predicting qualitatively correct Stark shifts.
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Barnbokens dilemma - både och eller antingen eller? : om pedagogik och estetik i den polemiska barnboksdebattenWiberg, Lina January 2010 (has links)
The discussion on whether the aesthetics or the pedagogy of children´s literature is the most important trait of the genre has been going on for quite some time. As children´s literature rose from a will to educate it is argued that pedagogy is forever imbued in the literature that addresses the child as its main reader. Literary scholars voices concern that the discussions about aesthetic expressions are being shunned in favor of that of educational values but does one exclude the other? In this essay I focus on two of Swedens most prominent authors of children´s literature, Lennart Hellsing and Ulf Stark. They are both part of the aesthetics/pedagogy debate, in their fictional works for children as well as with articles and essays on the subject. And even though they have similar standpoints regarding children´s literature their main directives with their own works differ. While Hellsing, an aesthetically oriented author has pedagogy as his foremost objective, Stark vehemently dissociates himself from that point of view thinking that literature for children should aim to be literature for literature´s sake. In this essay I try to find the opposite directives of these two writers in their own stories for children, that is to say pedagogic designs in Stark´s Liten och Stark and aesthetic intentions in Hellsings Krakel Spektakel-boken.
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Extraction of hydrocarbons from oil sand using supercritical carbon dioxidFang, Yi Unknown Date
No description available.
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Non-linear Optical Properties Of Two Dimensional Quantum Well StructuresAganoglu, Ruzin 01 February 2006 (has links) (PDF)
In this work optical properties of two dimensional quantum well structures are studied. Variational calculation of the eigenstates in an isolated quantum well structure with and without the external electrical field is presented. At weak fields a quadratic Stark shift is found whose magnitude depends strongly on the finite well depth. It is observed that under external electrical field, the asymmetries due to lack of inversion symmetry leads to higher order nonlinear optical effects such as second order optical polarization and second order optical susceptibility.
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Extraction of hydrocarbons from oil sand using supercritical carbon dioxidFang, Yi 11 1900 (has links)
This study investigates the extraction of hydrocarbons from oil sand using supercritical carbon dioxide (SC CO2). Experiments were carried out on three different types of oil sands. After some preliminary experiments, the feasibility of extracting hydrocarbons from oil sands by SC CO2 was confirmed and three experimental factors (pressure, temperature and mixing rate) were identified for further study. A two to the three factorial design was used to determine the significance of each factor and the significance of the interaction of the factors on the extraction efficiency. The extraction efficiency was calculated from Dean-Stark extraction analysis and was compared to the extraction efficiency based on gravimetric analysis. The results show that the extraction efficiency increased with pressure at a constant temperature. The effect of temperature on extraction efficiency is complex. The highest extraction efficiency was obtained at the high pressure (24.1MPa), high temperature (60C) and a mixing rate of 250rpm. / Environmental Science
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First-order geometric evolutions and semilinear evolution equations : a common mutational approachLorenz, Thomas January 2004 (has links) (PDF)
Heidelberg, Univ., Diss., 2004
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