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Understanding water and N transport through the soil profile is important for efficient irrigation and nutrient management to minimize nitrate leaching to the groundwater, and to promote agricultural sustainable development in desert oases. In this study, a process‐based water and nitrogen management model (WNMM) was used to simulate soil water movement, nitrate transport, and crop growth (maize [Zea maysL.]) under desert oasis conditions in northwestern China. The model was calibrated and validated with a field experiment. The model simulation results showed that about 35% of total water input and 58% of the total N input were leached to <1.8 m depth under traditional management practice. Excessive irrigation and N fertilizer application, high nitrate concentration in the irrigation water, together with the sandy soil texture, resulted in large nitrate leaching. Nitrate leaching was significantly reduced under the improved management practice suggested by farm extension personnel; however, the water and nitrate inputs still far exceeded the crop requirements. More than 1700 scenarios combining various types of irrigation and fertilizer practices were simulated. Quantitative analysis was conducted to obtain the best management practices (BMPs) with simultaneous consideration of crop yield, water use efficiency, fertilizer N use efficiency, and nitrate leaching. The results indicated that the BMPs under the specific desert oasis conditions are to irrigate the maize with 600 mm of water in eight times with a single fertilizer application at a rate of 75 kg N ha−1

At Koongarra, Australia, three drill cores from the Cahill Schist Formation containing U-ore, and regolith above it containing secondary U-ore, were studied to ascertain the distribution of rare earth elements (REEs) and U. The unaltered schist has a REE trend similar to the Post Archaean Australian Shale (PAAS), which is, therefore, used as a normalising standard. Unweathered rock from the zone of primary U mineralisation contained strong enrichment of the heavy REEs, and this pattern is retained during most of the weathering. Strongly bleached and very weathered shallow samples from this zone do not show enrichment of HREEs. In general, however, weathering appears to have little effect on the pattern of REEs in the bulk rock at this site. Zones rich in Mn oxy-hydroxides, occurring as coatings on fissure surfaces, contain large concentrations of Ce and U, with a clear Ce anomaly (Ce/ Ce*= 3.8). The Ce and U apparently occur together as microcrystalline oxides within (1–2 μm diameter) globules on mineral surfaces in the Mn-rich zones.

• Visual involvement was assessed in 21 patients with Friedreich's ataxia and in 17 patients with spastic ataxia by neuro-ophthalmic examination and by recording visual evoked responses (VERs). Two thirds of the patients with Friedreich's ataxia had some degree of visual impairment and an abnormal VER, whereas only three of the 17 patients with spastic ataxia showed abnormalities. The patients with Friedreich's ataxia could be subdivided into two groups, one with and the other without visual involvement; there was no correlation between the presence and severity of visual involvement and age or duration of symptoms in the group as a whole. Patients with the most severe degrees of visual impairment usually had flat VERs, whereas in less severely affected cases, the responses were reduced in amplitude, were delayed, and showed an increased degree of temporal dispersion. The findings have pathophysiological implications and raise the question of heterogeneity in Friedreich's ataxia.

Three patients who were admitted to hospital because of syncope were found to have malignant head and neck tumours. A patient who presented with malignant external otitis with syncope and postural hypotension is also described. It is postulated that the syncope and postural hypotension result from compressive irritation of the glossopharyngeal nerve either in the neck or at the base of the skull.

We investigated pupillary responses to parasympathetic (pilocarpine) and sympathetic agents (tyramine, cocaine, and phenylephrine) in a 51-year-old woman with tonic pupils, loss of muscle stretch reflexes in the limbs, and hemifacial loss of sweating and flushing (Ross' syndrome). A smaller pupillary response to tyramine and cocaine eyedrops on the symptomatic side indicated that outflow was disrupted in the postganglionic section of the ocular sympathetic pathway. A greater response to phenylephrine eyedrops on this side was consistent with denervation supersensitivity to adrenergic agents. Loss of thermoregulatory sweating and flushing and emotional blushing in the forehead, cheek, and chin indicated that sympathetic disruption was proximal to the bifurcation of the common carotid artery, probably in the superior cervical ganglion. A similar degenerative process may be responsible for loss of muscle stretch reflexes, tonic pupils, and other autonomie disturbances in Ross' syndrome.

A case of poisoning caused by an excessive dose of herbal laxative tablets is reported. The patient's symptoms included coma and prolonged peripheral neuropathy. The clinical features were characteristic of podophyllin poisoning. Podophyllin was a component of the laxative tablets, but the container gave no indication of their potential toxicity. Methods of reducing the risk of inadvertent poisoning by herbal remedies are suggested. (Med. J Aust 1984; 140: 495‐496)