The thermodynamics of disorder have been studied for hundreds of years, with physicists using entropy to quantitatively connect the macroscopic properties of a system to its microscopic multiplicity (disorder). Here, we consider the effect of disorder in magnetic materials. The pyrochlore oxides (A2B2O7), comprised of a bipartite lattice of corner-sharing tetrahedra, have been central to the study of geometric frustration for the past several decades. Pyrochlores, in which the A-site is occupied by the magnetic cation dysprosium, tend to exhibit spin ice ordering down to low temperatures, in spite of chemical perturbations to the B-site lattice. With the motivation of this study being the investigation of how adding B-site disorder to the traditional Dy2ScNbO7 form of Dy-pyrochlores, a stoichiometric mixture of Sc-3+ and Nb-5+ was used to synthesize Dy2ScNbO7, the pyrochlore material that is central to this thesis work. We show using magnetometry, heat capacity, muon spin relaxation, and inelastic neutron scattering that the mixed B-site pyrochlore Dy2ScNbO7, does not adopt the spin ice ground state. The low temperature spin dynamics are much faster than other analogous dysprosium pyrochlores, the residual entropy is significantly smaller than that predicted for a spin ice and there are low-lying crystal field excitations. These results all indicate that the B-site disorder appears to destroy the predicted Ising anisotropy of dysprosium. / Thesis / Master of Science (MSc)

Förskolan är en plats för alla barn, där pedagogers uppgift är att skapa de bästa förutsättningarna för alla barn. I förskolan kan olika känslor uppstå och det är en plats där vi utvecklas och lär oss att förstå att alla känslor är okej att känna. Vi har under vår verksamhetsförlagda utbildning kunnat se att barns ilska och frustration sker på samtliga förskolor och vi har upplevt att pedagoger använder olika strategier för att bemöta barnens ilska och frustration. Trots att vi alla känner olika känslor så finns det olika upplevelser kring dem. Alla barn är olika precis som vuxna, men barn har ännu inte utvecklat olika strategier för att hantera sin frustration och ilska. Vårt syfte med studien är att undersöka och synliggöra hur förskollärare samtalar i fokusgrupper och därigenom ger uttryck för hur de upplever förskolebarns ilska och frustration. Studien är baserad på en kvalitativ metod där vi under arbetets gång använt oss av en tematisk analys där de tre temana som framkom är tema 1: Att vara en närvarande pedagog, tema 2: Pedagogers strategier samt tema 3: Pedagogens relationer till barnen.   Resultatet visar att förskollärarnas upplevelser kring barns ilska och frustration är individuellt och ingen situation är den andra lik. Resultatet visade även att utifrån förskollärarnas erfarenheter och upplevelser är de lösningsorienterade vid hantering av barns ilska och frustration.

Our study investigates when people quit playing unaltered Valheim (2021) and what the inciting factors were among those frustrations. Research into occurrences of frustration helped us gain a better understanding of how players' expectations come into play as well as how players allocate their resources when it comes to video games. This understanding allows game developers to mitigate frustration in open-world survival games. The study was conducted by interviewing participants who had played the game for more than 25 hours and had quit playing unaltered Valheim (2021). The participants were obtained from a survey used to screen potential candidates for the interviews. We approach this study through the lens of Conservation of Resource theory and Need Frustration. We observed that participants' prior experience in games played a significant role, apart from the gameplay itself, in deciding whether the game they played was worth the resources they chose to invest. Ultimately, the participants felt that the game was being unfair towards them and to continue playing the unaltered game would be a waste of resources.

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Min studie syftar till att få reda på vad som ligger bakom några av de negativa uttalanden som figurerar kring Arbetsförmedlingen (Af) och genom att berätta om Af:s verksamhet försöka höja kunskapsnivån om Arbetsförmedlingen. Jag har med hjälp av fem kvalitativa intervjuer kommit fram till att det i intervjupersonernas fall i det stora hela handlar om frustration och bemötandet samt okunskap om Af:s verksamhet vilket har lett till felaktiga förväntningar. Ett intressant resultat var att intervjupersonerna trots sina negativa uttalanden inte var särskilt negativa i sin inställning under intervjutillfället, och detta förklarar jag med att det handlar om enstaka händelser, som leder till ilska och frustration, som ligger bakom – det handlar inte om att allt Arbetsförmedlingen gör är negativt. Jag ville också få en inblick i hur fem företag och organisationer ser på Arbetsförmedlingen och höra vilka anledningar de trodde låg bakom de negativa uttalandena. För att få deras perspektiv träffade jag fem personer från olika företag för intervjuer, och det kom fram att de flesta av dessa företag också var relativt positiva till Af. Även här såg jag dock bristande kunskaper om Arbetsförmedlingens verksamhet. Olika åsikter om anledningen till kritiken kom fram, men i stort sett handlar det om bemötandet, resursproblem och massmedias påverkan samt klass och felaktiga förväntningar.Som analysinstrument till dessa totalt tio intervjuer använder jag mig av flera olika teorier: medias påverkan, social psykologi, okunskap och vägledningsteorier. Jag menar att dessa förklarar den bredd resultatet från intervjuerna gav.

Kjellstedt, C & Grönqvist, S. Sjuksköterskans upplevelse av otillräcklig smärtlindring. En fenomenologisk studie. Examensarbete i omvårdnad 15 poäng. Malmö högskola: Hälsa och Samhälle, Utbildningsområde, Omvårdnad, 2010.Sjuksköterskan möter dagligen patienter med smärta och har en nyckelposition när det gäller att bedöma patienters smärta samt utvärdera smärtbehandlingen. Syftet med denna studie var att beskriva sjuksköterskans upplevelse och känslomässiga hantering av att inte kunna smärtlindra patienter, ur ett avancerad nybörjar- expert perspektiv. I denna studie användes Giorgis deskriptiv fenomenologi. Totalt fyra djupintervjuer med sjuksköterskor på en somatisk avdelning genomfördes. Patricia Benners stadier avancerad nybörjare och expert användes för att skapa en djupare förståelse för sjuksköterskans upplevelser. Resultatet visar att sjuksköterskor känner sig frustrerade och maktlösa då de inte kan lindra patienters smärta. Att hantera dessa känslor kräver både klinisk erfarenhet och en god gemenskap på avdelningen. Avancerade nybörjares bristande kliniska erfarenhet får till följd att de har ett större behov av stöd från kollegor. Nyckelord: Avancerad nybörjare, deskriptiv fenomenologi, expertsjuksköterska, frustration, smärtlindring, upplevelse. / Kjellstedt, C & Grönqvist, S. Nurse´s experiences of inadequate pain relief. A phenomenological study. Degree project in Nursing 15 Credit Points. Malmö University. Health and Society, Department of Nursing, 2010.A nurse daily meets patients who suffer from pain and has a key role in assessing this pain as well as in evaluating the treatment plan. The aim of this study was to describe some nurses’ experiences and emotional coping of not being able to relieve the patient’s pain, from an advanced beginner- expert nurse perspective. For this study Giorgi’s descriptive phenomenological approach was used. A total of four in depth interviews was conducted with nurses working at a hospital ward. Patricia Benner’s theory of advanced beginners and expert nurses was used to give a deeper understanding of the nurse’s experiences. The result show that nurses experience feelings of frustration and powerlessness when not being able to relieve a patient’s pain. Coping with these feelings needs clinical knowledge as well as a good atmosphere on the ward. Due to their lack of clinical knowledge advanced beginners has a bigger need for support from colleagues. Keywords: Advanced beginners, descriptive phenomenology, expert nurses, frustration, pain relief, experiences.

No description available.

No description available.

<p>Yb2Ti2O7 is one member of a series of magnetic compounds with the pyrochlore lattice structure. For specific types of single-ion anisotropy and exchange interactions, the geometry of the pyrochlore lattice frustrates near-neighbor interactions and coaxes a wide variety of unusual magnetic ground states from such compounds. Yb2Ti2O7 is unique among these compounds in that the source of the frustration is not immediately obvious when one considers the combination of single-ion anisotropy (XY-like) and the nature of the exchange interactions (ferromagnetic) present therein. A conventional magnetic transition was indeed initially expected based on the observation of specific heat anomaly near 200mK. However, many studies produced no signs of long-range magnetic order below this temperature. Intriguingly, above the transition, evidence for unusual two-dimensional correlations came in the form of rods of magnetic diffuse neutron scattering. This thesis contains four articles that detail the results of several neutron scattering studies on Yb2Ti2O7. The goal of these studies was to determine the nature of the static and dynamic spin correlations throughout the magnetic field vs. temperature phase diagram of Yb2Ti2O7.</p> <p>We first performed a time-of-flight neutron scattering experiment on a single crystal of Yb2Ti2O7, which we prepared using the optical floating zone method. This initial study provided a comprehensive survey of the phase diagram, including the previously unexplored response to a magnetic field. We found that the rods of diffuse scattering change qualitatively upon cooling below the temperature of the reported specific heat anomaly, showing signs for the development of short-range three-dimensional correlations. Additionally, we discovered that a relatively small magnetic field applied along the [110] direction could remove the diffuse scattering entirely, and produce sharp spin wave excitations in the inelastic channel, indicating long range spin correlations.</p> <p>We further quantified the temperature dependence of the diffuse scattering in zero-field using a triple-axis neutron spectrometer. The crossover from two-dimensional correlations to short-range three-dimensional correlations was found to begin at 400mK and reach completion near the temperature of the specific heat anomaly, ∼200mK. Our measurements of the low temperature specific heat of several single crystal samples, as well as a powder sample, revealed that significant sample-dependence of the magnetic properties exists. The single crystal samples were shown to have broader features in the specific heat at relatively low temperatures compared to the powder samples, pointing to some amount of structural disorder in the single crystals.</p> <p>To understand the nature of the structural defects in the single crystals, we compared the structure of a crushed single crystal of Yb2Ti2O7 to that of a powder sample using neutron powder diffraction. The major conclusion of that work was that the single crystal is non-stoichiometric, containing 2.3% excess ytterbium on the (non-magnetic) titanium sublattice. The introduction of additional magnetic moments into the system is expected to be the cause of the sample-dependence of the specific heat anomaly.</p> <p>Finally, we fit the spin wave dispersions in the field-polarized state, as measured by time-of-flight inelastic neutron scattering, to an effective spin-1/2 anisotropic exchange Hamiltonian. The microscopic parameters extracted from these fits place Yb2Ti2O7 close to exotic Quantum Spin Liquid phases predicted for the anisotropic spin-1/2 pryochlore model. The exchange parameters also reveal that the source of the frustration in Yb2Ti2O7 comes from the “quantum spin ice” nature of its exchange interactions.</p> / Doctor of Philosophy (PhD)

The rare earth pyrochlore oxides, with formula R2B2O7, are a chemically versatile family of materials that exhibit a diverse array of magnetic phenomena. In this structure the R and B site cations each form a corner-sharing tetrahedral network, a motif that is prone to intense geometric magnetic frustration. As a consequence of their magnetic frustration, rare earth pyrochlores are observed to host a number of remarkable states such as spin ice and spin liquid states. In this thesis we endeavor to explore the phase diagrams of the rare earth pyrochlores through the lens of chemical pressure. Chemical pressure is applied by varying the ionic radius of the non-magnetic B site cation, which either expands or contracts the lattice, in analogy to externally applied pressure. We apply positive chemical pressure by substituting germanium at the B site and negative chemical pressure by substituting lead at the B site. We also consider the effect of platinum substitution, which has nominally negligible chemical pressure effects. In the ytterbium pyrochlores, we find that positive chemical pressure tunes the magnetic ground state from ferromagnetic to antiferromagnetic. Remarkably, we also find that the ytterbium pyrochlores share a ubiquitous form to their low temperature spin dynamics despite their disparate ordered states. In the terbium pyrochlores, we find that positive chemical pressure promotes ferromagnetic correlations - the opposite effect of externally applied pressure. Our studies of platinum pyrochlores reveal that platinum, while non-magnetic, is able to facilitate superexchange pathways. Thus, the magnetic ground states of the platinum pyrochlores are significantly altered from their titanate analogs. The work in this thesis highlights the delicate balance of interactions inherent to rare earth pyrochlore magnetism and shows that chemical pressure is a powerful tool for navigating their phase spaces. / Thesis / Doctor of Philosophy (PhD) / Rare earth pyrochlores have the chemical formula R2B2O7, where R is a magnetic rare earth element and B is a non-magnetic element. Materials of this type are widely studied because they have a propensity to exhibit exotic magnetic properties. In this thesis, we study the effect of varying the size of the non-magnetic B site atom, which is termed chemical pressure. As B is made larger or smaller, the crystal lattice expands or contracts, mimicking the effect of externally applied pressure. High-pressure synthesis techniques were used to prepare R2B2O7 compounds with B site cations that are typically too small (germanium), too large (lead), or too unstable (platinum) under ambient pressure conditions. Our characterizations of these high-pressure materials have revealed that their magnetism is remarkably sensitive to the application of chemical pressure.