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Excretion of biopterin and the related pteridines neo-pterin and pterin was measured in urine samples from a group of 25 male and 51 female depressed outpatients receiving lithium therapy, and compared to 61 male and female control subjects. The ratio of neopterin to biopterin excreted (N/B) was significantly higher in the patients than controls (p< 0.01), and the significant (p< 0.01) positive correlation between urinary neopterin and biopterin shown by the controls was absent in the patients, indicating disrupted biosynthesis of BH4. Urinary cortisol excretion was similar in all groups, but creatinine excretion was diminished in the patients, suggesting a nephrogenic effect of lithium. Serum folate was shown to correlate with urinary biopterin in female unipolar patients. Two groups of elderly females with senile dementia of Alzheimer type (SDAT) were examined for urinary pteridine excretion. In group I (n= 10), N/B was significantly higher than in 24 controls (p< 0.05) and the ratio B/B+ N significantly lower, indicating diminished tetrahydrobiopterin biosynthesis. A second study on 30 patients and 24 age-matched controls confirmed these findings. However, as N correlated with B in both patients and controls, the alteration in BH4 metabolism in SDAT is possibly different to that shown in depression. Lithium had no effect in vivo or in vitro on wistar rat brain or liver BH4 biosynthesis or salvage enzyme dihydropteridine reductase at a range of concentrations and duration of dosing period. In general, no significant effects were shown by the tricyclic antidepressant imipramine, the anticonvulsant sodium valproate, the vitamin folic acid or the anticholinergic agent methylparatyrosine, indicating that BH_4 may differ in man and rat. The synthetic corticosteroid dexamethasone had no effect on rat brain metabolism, nor did stimulation of natural cortisol by stress-immobilisation, although hypothalamic-pituitary-adrenal axis disturbances are know in depression.

Factors affecting the diversity and abundance of wading birds during the breeding season were studied on an area of moorland and marginal hill farmland in part of Upper Teesdale. Several vegetation types, on both peat and mineral soils, were available as breeding sites. Low vegetation height and an open, treeless habitat favoured by most wader species was maintained by a combination of management for grouse moor and sheep grazing. The interpretation of multivariate analyses suggested that vegetation type and altitude were the most important determinants of distribution for Lapwing, Redshank, Snipe, Curlew, Golden Plover and Dunlin. Wader species richness and abundance decreased with altitude, approximately one species being lost for every 100m increase in altitude. Both relationships were independent of vegetation type and were thought to be food-related. Within the marginal hill farmland, fields with a cover of Juncus effusus exceeding 5% had the highest breeding densities of waders and were preferentially selected by Lapwing, Redshank, Snipe and Curlew. The proximate factors involved in the selection of fields by these species were typically associated with wet habitats, e.g. marshy patches, the cover and distribution of J. effusus, and flat areas. Species richness was greatest on the large, wet, unmanaged fields. Only Lapwing commonly bred on the drier hay meadows. Three wader species, Common Sandpiper, Oystercatcher and Ringed Plover were notably restricted to bodies of permanent standing water. Of these only Common Sandpiper were abundant, breeding densities varying in accordance with stream width and the number of shingle banks which were used as feeding areas. The formation of Cow Green Reservoir in 1970 seems to have been responsible for attracting Ringed Plover as a new breeding species to Upper Teesdale. Changes of land use in upland areas have important consequences for many wader species. From a consideration of factors affecting the diversity and abundance of wading birds in Upper Teesdale, the implications of such changes were discussed with reference to the management and conservation of upland areas as habitats for breeding waders.

The introductory section is taken up with an examination of the moral climate of the society in which Mme de Lafayette wrote. The eclectic nature of honnetete is pointed out, together with its lack of concern for perfection to which it preferred a pursuit of refined pleasure guided by reason, Mme de Lafayette's ethics are found to be those of her generation in the setting of her novel, whilst her conception of love presents greater complexities, Mme de Villedieu is seen to preach a doctrine of hedonism which reflects exactly 'mondain' mentality, A study of the feminine novel from 1678 to 1703, at which point it seems to have suffered a relative eclipse, shows that whereas women writers portrayed passion and not amorous dalliance, they remain faithful to the ideal held by an earlier generation: that of pure love. Their conception of passion as omnipotent, together with the absolute virtue of the protagonists, means that there is no real moral dilemma. The heroes and heroines are thus represented as being worthy of pity, and their helplessness leads them to adopt a fatalistic attitude. The didactic aim, which had been so strong in the novel, tends thus to be replaced by a desire to move the reader. The moral notions, which act as an accurate guide to the ethics implied in the novels, reflect this change of emphasis from the struggle of will to the portrayal of sensitivity and suffering virtue. Such notions as 'la delicatesse', which has replaced 'la gloire' in importance, seem to hold the key to the understanding of this new ideal, A comparison with the contemporaneous masculine novel demonstrates the unity of tone in the novels of women writers; from the masculine novel is absent such evidence of moral preoccupation as we have found in the main part of this study. Thus it is to the works of women writers from the publication of the Princesse de Cleves until the end of the reign of Louis XIV that the credit must go for the development of the cult of sensibility in the novel.

The purpose of this study was to identify factors that contributed to differences in clinical problem solving among nursing students within and across three levels of university-based education. Formal education as well as scores on a knowledge test of basic Medical-Surgical Nursing, the Watson-Glaser Critical Thinking Appraisal (WGCTA), and nursing practice experience were used to predict performance on three written clinical simulations of Medical-Surgical Nursing. A cross-sectional, convenience sample of 59 currently enrolled nursing students completed all instruments. Subjects were asked to give their hypotheses regarding the likely physiological alterations exhibited by the simulation patients. They also indicated the information they used to formulate their hypotheses and data they would gather to confirm their initial hypothesis. Separate data analyses were conducted for each of the simulations. The results revealed that the most difficult simulation was Wound Dehiscence, followed by Congestive Heart Failure and Hypoglycemia Reaction. Within the total sample the best predictors of the Wound Dehiscence simulation performance were formal education and Nursing Assistant Experience. The best predictors of Hypoglycemia were Nursing Assistant Experience and nursing knowledge, and for the Congestive Heart Failure simulation, they were knowledge and problem solving. The within education group analyses revealed variations in performance on the simulations that were attributable to individual differences in knowledge, general problem solving and experience. A comparison of the best problem solvers with the others revealed that they excelled in identifying the information needed to generate the hypotheses. The results of the study are discussed in terms of their implications for further research and nursing education. Among the key questions raised by the results were: How does nursing experience enhance students' ability to identify key information in simulated clinical problems? Why is critical thinking a significant predictor of one's ability to specify data needed to confirm hypotheses? The findings also highlights the need to further refine instruments used in assessing nurses' clinical judgement. Foremost among the implications for education were: (1) to provide more opportunities for nursing students to apply knowledge and clinical problem solving skills; and (2) foster active reflection in and on their practice to facilitate the integration and synthesis of skills associated with critical thinking/problem solving.