998 resultados para Anomalous experiences
Resumo:
Evidence demonstrates food insecurity has a detrimental impact on a range of outcomes for children, but little research has been conducted in the UK, and children have rarely been asked to describe their experiences directly. We examined the experiences of food insecure families living in South London. Our mixed-methods approach comprised a survey of parents (n = 72) and one-to-one semi-structured interviews with children aged 5-11 years (n = 19). The majority of parents (86%) described their food security during the preceding year as very low. Most reported they had often or sometimes had insufficient food, and almost all had worried about running out of food. Two thirds of parents had gone hungry. Most parents reported they had been unable to afford a nutritionally balanced diet for their children, and just under half reported that their children had gone hungry. Four themes emerged from the interviews with children: sources of food; security of food, nutritional quality of food, and experiences of hunger. Children's descriptions of insufficient food being available indicate that parents are not always able to shield them from the impact of food insecurity. The lack of school-meals and after-school clubs serving food made weekends particularly problematic for some children. A notable consequence of food insecurity appears to be reliance on low-cost takeaway food, likely to be nutritionally poor.
Resumo:
Ubiquitous computing aims at providing services to users in everyday environments such as the home. One research theme in this area is that of building capture and access applications which support information to be recorded ( captured) during a live experience toward automatically producing documents for review (accessed). The recording demands instrumented environments with devices such as microphones, cameras, sensors and electronic whiteboards. Since each experience is usually related to many others ( e. g. several meetings of a project), there is a demand for mechanisms supporting the automatic linking among documents relative to different experiences. In this paper we present original results relative to the integration of our previous efforts in the Infrastructure for Capturing, Accessing, Linking, Storing and Presenting information (CALiSP). Ubiquitous computing aims at providing services to users in everyday environments such as the home. One research theme in this area is that of building capture and access applications which support information to be recorded (captured) during a live experience toward automatically producing documents for review (accessed). The recording demands instrumented environments with devices such as microphones, cameras, sensors and electronic whiteboards. Since each experience is usually related to many others (e.g. several meetings of a project), there is a demand for mechanisms supporting the automatic linking among documents relative to different experiences. In this paper we present original results relative to the integration of our previous efforts in the Infrastructure for Capturing, Accessing, Linking, Storing and Presenting information (CALiSP).
Resumo:
We show, by using a numerical analysis, that the dynamic toward equilibrium for an electrolytic cell subject to a step-like external electric field is a multirelaxation process when the diffusion coefficients of positive and negative ions are different. By assuming that the diffusion coefficient of positive ions is constant, we observe that the number of involved relaxation processes increases when the diffusion coefficient of the negative ions diminishes. Furthermore, two of the relaxation times depend nonmonotonically on the ratio of the diffusion coefficients. This result is unexpected, because the ionic drift velocity, by means of which the ions move to reach the equilibrium distribution, increases with increasing ionic mobility.
Resumo:
Dispersions of saturated anionic phospholipid dimyristoyl phosphatidylglycerol (DMPG) have been extensively studied regarding their peculiar thermostructural behavior. At low ionic strength, the gel-fluid transition is spread along nearly 17 degrees C, displaying several thermal events in the calorimetric profile that is quite different from the single sharp peak around 23 degrees C found for higher ionic strength DMPG dispersions. To investigate the role of charge in the bilayer transition, we carefully examine the temperature dependence of the electrical conductivity of DMPG dispersions at different concentrations, correlating the data with the corresponding differential scanning calorimetry (DSC) traces. Electrical conductivity together with electrophoretic mobility measurements allowed the calculation of the dependence of the degree of ionization of DMPG vesicles on lipid concentration and temperature. It was shown that there is a decrease in vesicle charge as the lipid concentration increases, which is probably correlated with the increase in the concentration of bulk Na(+). Apart from the known increase in the electrical conductivity along the DMPG temperature transition region, a sharp rise was observed at the bilayer pretransition for all lipid concentrations studied, possibly indicating that the beginning of the chain melting process is associated with an increase in bilayer ionization. It is confirmed here that the gel-fluid transition of DMPG at low ionic strength is accompanied by a huge increase in the dispersion viscosity. However, it is shown that this measured macroviscosity is distinct from the local viscosity felt by either charged ions or DMPG charged aggregates in measurements of electrical conductivity or electrophoretic mobility, Data presented here give support to the idea that DMPG vesicles, at low ionic strength, get more ionized along the temperature transition region and could be perforated and/or deformed vesicle structures.
Resumo:
The photoactivation of a photosensitizer is the initial step in photodynamic therapy (PDT) where photochemical reactions result in the production of reactive oxygen species and eventually cell death. In addition to oxidizing biomolecules, some of these photochemical reactions lead to photosensitizer degradation at a rate dependent on the oxygen concentration among other factors. We investigated photodegradation of Photogem A (R) (28 mu M), a hematoporphyrin derivative, at different oxygen concentrations (9.4 to 625.0 mu M) in aqueous solution. The degradation was monitored by fluorescence spectroscopy. The degradation rate (M/s) increases as the oxygen concentration increases when the molar ratio of oxygen to PhotogemA (R) is greater than 1. At lower oxygen concentrations (< 25 mu M) an inversion of this behavior was observed. The data do not fit a simple kinetic model of first-order dependence on oxygen concentration. This inversion of the degradation rate at low oxygen concentration has not previously been demonstrated and highlights the relationship between photosensitizer and oxygen concentrations in determining the photobleaching mechanism(s). The findings demonstrate that current models for photobleaching are insufficient to explain completely the effects at low oxygen concentration.
Resumo:
Anomalous and natural concentrations of Cr(6+), occasionally exceeding the permitted limit for human consumption (0.05 mg/L), have been detected in groundwater in the northwestern region of the state of Sao Paulo. As part of a water-rock interaction investigation, this article describes the chemical and mineralogical characterization of rock samples taken from boreholes in the municipality of Urania, with the objective of identifying Cr-bearing minerals and determining how chromium is associated with these minerals. Rock sample analysis were performed using X-ray Fluorescence, X-ray Diffraction, Scanning Electron Microscopy, electron microprobe and sequential extraction techniques. Chemical analyses indicated that the quartzose sandstones show a geochemical anomaly of chromium, with an average content of 221 ppm, which is higher than the reported chromium content of generic sandstones (35 ppm). Diopside was identified as the primary Cr-bearing mineral potentially subject to weathering processes, with a chromium content of up to 1.2% as Cr(2)O(3). Many of the diopside grains showed dissolution features, confirming the occurrence of weathering. Sequential extraction experiments indicated that 99.3% of the chromium in samples is tightly bonded to minerals, whereas 0.24% is weakly bonded via adsorption. Assuming hypothetically that all adsorbed chromium is released via desorption, the theoretical Cr concentration in water would be one order of magnitude higher than the concentrations of Cr(6+) detected in groundwater. (C) 2010 Elsevier Ltd. All rights reserved.
Resumo:
Sammanfattning: Bakgrund: för många pappor kan det vara en av livets största och bästa stund att närvara vid när deras barn föds. Det finns studier som beskriver pappors upplevelse av sjukhusförlossning, däremot finns det få studier som beskriver pappors upplevelse av planerad hemförlossning. Syftet med den här studien är att beskriva pappans upplevelser och erfarenheter av planerad hemförlossning. Metod: i denna studie medverkar 105 pappor från de nordiska länderna som har deltagit i planerad hemförlossning mellan 2009-2011. Materialet från en öppen enkätfråga analyserades med hjälp av deduktiv ansats. Den öppna frågan löd ”beskriv gärna förlossningen med egna ord”. Resultat: papporna upplevde den planerade hemförlossningen som lugn och säker, mycket tack vare den professionella barnmorskan och den välbekanta miljön. Att få vara hemma med sin partner och om så önskades, sin familj var högt skattat. Födelseprocessen hemma beskrevs av papporna som att ”vi gjorde det tillsammans” och ”det var vår egen förlossning”. Papporna uttryckte delaktighet i förlossningsflödet. De kände också att de fick ett barn och var en del av en vacker förlossning full av kärlek. Konklusion: att välkomna ett barn hemma i en lugn miljö där paret känner sig trygga och ostörda, kan underlätta en positiv och meningsfull förlossningsupplevelse.
Resumo:
In Vietnam, as in other Asian countries, co-operation with foreign universities plays an important role for the development of higher education. This paper is based on personal experiences from teaching a Swedish Master Programme in Education Science at Vietnam National University in Hanoi. Using theories developed by Lev Vygotsky and Donald Schon, the programme is explored as an inter-cultural learning process. Three aspects are focused upon. Firstly, the fact that communication between students and teachers is conducted with the help of translators who support both teachers and students in their attempt to understand and make themselves understood. Secondly, the expressed need to connect the ideas and techniques which are studied in the programme to the students´ professional worlds. Thirdly, the need to construct a framework wherein the students can inquire into their own situations and to encourage them to try new and more productive ways to deal with problems they are confronted with.
Resumo:
We have obtained numerically exact results for the spin-related geometric quantum phases that arise in p-type semiconductor ring structures. The interplay between gate-controllable (Rashba) spin splitting and quantum-confinement-induced mixing between hole-spin states causes a much higher sensitivity of magnetoconductance oscillations to external parameters than previously expected. Our results imply a much-enhanced functionality of hole-ring spin-interference devices and shed new light on recent experimental findings.
Resumo:
The overall aim of this thesis was to explore surgical nurses’ experiences of being confronted with patients’ existential issues when caring for patients with cancer, and to examine whether an educational intervention may support nurses in addressing existential needs when caring for patients with cancer. Previously recorded discussions from supervision sessions with eight healthcare professionals were analysed (I), written descriptions of critical incidents were collected from 10 nurses, and interviews with open questions were conducted (II). An educational intervention on existential issues was pilot tested and is presented in Studies III and IV. The intervention was the basis of a pilot study with the purpose of testing whether the whole design of the educational intervention, including measurements instruments, is appropriate. In Study III and IV interviews with 11 nurses were conducted and 42 nurses were included in the quantitative measurements of four questionnaires, which were distributed and collected. Data was analysed using qualitative secondary analysis (I), hermeneutical analysis (II), and mixed methods using qualitative content analysis and statistical analyses (III-IV). Results in all studies show that existential issues are part of caring at surgical wards. However, although the nurses were aware of them, they found it difficult to acknowledge these issues owing to for example insecurity (I-III), a strict medical focus (II) and/or lacking strategies (I-III) for communicating on these issues. Modest results from the pilot study are reported and suggest beneficial influences of a support in communication on existential issues (III). The results indicate that the educational intervention may enhance nurses’ understanding for the patient’s situation (IV), help them deal with own insecurity and powerlessness in communication (III), and increase the value of caring for severely ill and dying patients (III) in addition to reducing work-related stress (IV). An outcome of all the studies in this thesis was that surgical nurses consider it crucial to have time and opportunity to reflect on caring situations together with colleagues. In addition, descriptions in Studies III and IV show the value of relating reflection to a theory or philosophy in order for attitudes to be brought to awareness and for new strategies to be developed.