Pathologies in the sticky limit of hard-sphere-Yukawa models for colloidal fluids. A possible correction

A known `sticky-hard-sphere' model, defined starting from a hard-sphere-Yukawa potential and taking the limit of infinite amplitude and vanishing range with their product remaining constant, is shown to be ill-defined. This is because its Hamiltonian (which we call SHS2) leads to an {\it exact}second virial coefficient which {\it diverges}, unlike that of Baxter's original model (SHS1). This deficiency has never been observed so far, since the linearization implicit in the `mean spherical approximation' (MSA), within which the model is analytically solvable, partly {\it masks} such a pathology. To overcome this drawback and retain some useful features of SHS2, we propose both a new model (SHS3) and a new closure (`modified MSA'), whose combination yields an analytic solution formally identical with the SHS2-MSA one. This mapping allows to recover many results derived from SHS2, after a re-interpretation within a correct framework. Possible developments are finally indicated.Comment: 21 pages, 1 figure, accepted in Molecular Physics (2003

The shape and measurements of the forced expiratory spirograms in healthy children

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A clinical classification of the idiopathic respiratory distress syndrome of the newborn

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A review of the respiratory distress syndrome in Cape Town

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The history of a War Memorial Children's Hospital in Cape Town

No Abstract. South African Medical Journal Vol. 96(9) (Part 2) 2006: 854-86

Health care of children

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Asphyxia Neonatorum-Neurological Status at One Year Follow-Up

The neurological status at one year follow-up of a group of infants who had suffered from asphyxia neonatorum is described. The situation at the end of the first week is contrasted with that a year later

An assessment of the 'road-to-health' card based on perceptions of clinic staff and mothers

Objectives. To describe the opinions of health personnel and parents at child health clinics in Cape Town; to determine the accuracy and completeness of data recorded on the present 'Road-to-Health' (RTB) card; and to ascertain the views of clinic staff and mothers regarding what information they would like to record.Design. Descriptive prospective study.Setting and subjects. Qualitative interviews of 35 health personnel and 150 mothers/caregivers were conducted at 17 child health clinics. The clinic practices of 32 health personnel were monitored and details of 150 RTH cards were examined.Main outcome measures. Responses of health personnel at public and private child health clinics and of mothers were analysed. Data recorded on the card were extracted under the headings: neonatal data, immunisation schedules, measurements, and weight-for-age chart.Results. Most nurses supported the concept of an RTH card but a large majority recommended that it be replaced with a notebook retained by the mother. A significant proportion of health personnel did not know how to use the weight-for-age chart. Most mothers attending clinics carried the card, but this number dropped for hospital visits and consultations with private doctors. Mothers' understanding of the card was limited. For mothers the weight-for-age chart, immunisation schedule and milestone section are obscure.Conclusion. Health personnel and mothers would like to replace the RTH card with a notebook in the parents' home language. It should contain more information on health matters, adequate space to record weight and infectious diseases, an illustrated milestone chart and an improved schedule for immunisations. Mothers perceived the RTH card as belonging to the clinic and wanted a 'baby's own' document