RESUMO
Using the Oxford Human Milk Pasteuriser human milk was exposed to lower temperature and shorter time periods than employed in classical holder pasteurisation. Heating human milk at 62.5 degrees C for 5 min completely destroyed Escherichia coli, Staphylococcus aureus, and group B beta-haemolytic streptococci inoculated into the samples. Heating at 56.0 degrees C for 15 min destroyed over 99% of the inoculated organisms. The mean percentage remaining activity of certain antimicrobial proteins after heat treatment at 62.5 degrees C for 30 min, 62.5 degrees C for 5 min and 56 degrees C for 15 min were as follows: IgA 67, and 90%; lactoferrin 27, 59 and 91%; and lysozyme 67, 96 and 106%, respectively. These results suggest that human milk can be effectively pasteurised using less heat treatment than in classical holder pasteurisation. Lower temperature and shorter heat treatment also preserves substantially more of the activity of the antimicrobial proteins present in human milk.
Assuntos
Temperatura Alta , Leite Humano/microbiologia , Escherichia coli/isolamento & purificação , Feminino , Humanos , Imunoglobulina A/análise , Lactoferrina/análise , Leite Humano/análise , Leite Humano/imunologia , Muramidase/análise , Staphylococcus aureus/isolamento & purificação , Streptococcus agalactiae/isolamento & purificação , Fatores de TempoRESUMO
We present a simple nonlinear system that exhibits multiple distinct stochastic resonances. By adjusting the noise and coupling of an array of underdamped, monostable oscillators, we modify the array's natural frequencies so that the spectral response of a typical oscillator in an array of N oscillators exhibits N-1 different stochastic resonances. Such families of resonances may elucidate and facilitate a variety of noise-mediated cooperative phenomena, such as noise-enhanced propagation, in a broad class of similar nonlinear systems.
RESUMO
The role of the nurse teacher in the clinical area is a major issue in nurse education today. When attempting to define the role, identification of teacher behaviours that are effective and valued by students is essential. Whilst there is no shortage of literature addressing nurse educationalists' opinions of the nature of the present and future role, there is a paucity of papers reflecting students' views, and UK students in particular. The aim of this descriptive survey was to discover the views of third year RGN diploma level student nurses regarding the link teacher behaviours that help them to learn. One hundred and two student nurses completed a written questionnaire seeking information about the number and length of link teacher visits, and ratings of the level of helpfulness of 5 categories of link teacher behaviours. The Statgraphics statistical package aided the production of descriptive statistics, and also validation of the internal construct of the behaviour categories. Results showed that the majority of students were dissatisfied with the amount of link teacher contact they receive. A minimum length of time for each visit was established. The link teacher behaviours found to be most helpful were related to interpersonal skills and personality followed by nursing competence, evaluation and teaching ability. The findings contribute to the literature addressing UK students' views, and will inform the development of a higher quality link teacher support system for senior student nurses.