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Normal maize starch was extruded with and without the addition of fatty acid potassium salts in a twin screw cooker extruder equipped with a slit die rheometer, at 100, 120, 140 or 160 °C barrel temperatures and at screw speeds 20, 91, 161 or 227 rpm. The in line melt viscosity measurements showed that the flow behaviour of the starch system was influenced by the addition of either myristic or palmitic acids used. The examination of functional properties of the extrudates such as bulk density, water solubility index, expansion ratio, degree of gelatinization and water adsorptivity indicated that the addition of fatty acids affected the functionality of starch systems. That is, the extrudate texture became more cohesive and compact whereas the water solubility exhibited by the system was decreased. Structural studies indicated that the crystallinity of starch–fatty acid extrudates was higher than that of the starch systems without fatty acid whereas all extrudates exhibited high glass transition temperatures and their structure was very rigid and brittle.

The structure formation of yogurt gels made from bovine pasteurized milk of various fat contents (0%, 1.5% or 3.5%) and prepared using natural yogurt as a starter was monitored by measuring the rigidity modulus (G') development by means of a dynamic U-tube rheometer of novel design. The results indicated that both the heating pretreatment of the milk and its fat content significantly affect the rate of gelation as well as the final rigidity attained by the gel. That is, the higher the heating temperature employed and the higher the fat content was, the faster the onset gelation appeared to be and the more rigid was the gel network formed. The shape of the gelation curves of yogurt samples made from milk, either with or without fat, heated at 80, 85, 90 or 95 °C for 1 min and fermented at 45 °C, showed three distinctive parts indicating that the yogurt gelation process took place in three consecutive stages. The results are discussed in the light of a proposed mechanism which could explain the above mentioned findings.

The way in which the cerebellum influences the output of the motor cortex is not known. The aim of this study was to establish whether information about force, velocity or duration of movement is encoded in cerebellar thalamic discharge and could therefore be involved in the modulation of motor cortical activity. Extracellular single cell recordings were made from the cerebellar thalamus (66 neurones) and VPLc (49 neurones) of four conscious macaques performing simple wrist movements with various load and gain conditions imposed. A significant correlation (Spearman's; P

The effects of stimulus rise-fall and plateau times on the middle-latency response (MLR) waveform (Na-Pa amplitude and Pa latency) were investigated in 14 normally hearing subjects and an objective MLR threshold was evaluated at low and middle frequencies in ten normally hearing subjects and ten patients with slope of sensorineural hearing loss, using a selected stimulus-envelope time. After analyzing the effects of envelope times on the MLR waveform and the spectra of tone-pips, it was found that a rise-fall time of 4 ms with a plateau of 2 ms (4–2–4) is an acceptable compromise between a synchronous discharge and frequency specificity for estimating the MLR threshold. The MLR threshold produced by 4–2–4 tone-pips approximated the psychoacoustic threshold at low and middle frequencies in the normal and hearing impaired subjects. This demonstrates the clinical usefulness of the MLR in estimating low- and middle-frequency thresholds.

In an intensive Care Unit, mechanical ventilation is required by patients with respiratory failure. The purpose of the mechanical ventilation is to ensure that the patient's blood oxygen (O 2 ) and carbon dioxide (CO 2 ) levels are maintained at correct values. Automation of this process offers the possibility of improved patient care and relief from routine repetitive tasks for the heavily committed intensive care clinical staff. This paper describes an expert system based strategy for automatically adjusting ventilator setting to regulate blood O 2 and CO 2 levels. The system has two levels of expertise. At the lower level, separate control loops have been developed to individually manage blood O 2 and CO 2 . At a higher level of control, an expert system has been established which coordinates the concurrent operation of the two loops in order to ensure that disturbances to patient blood gas levels are handled in the most effective way.

Patient Controlled analgesia (PCA) has become accepted as an important means of self regulated relief from post surgical pain. In commonly used PCA systems, patients use a hand held push button to indicate the presence of pain and initiate a predetermined bolus of drug infusion. A disadvantage of this system is that no means is provided to accommodate variations in the intensity of pain or the sensitivity of the patient to the analgesic in use. The PCA system described in this paper uses a specially designed handset which allows the patient to indicate pain intensity and so vary the level of the drug infusion. Data derived from the handset signals provides a basis for adapting the drug dosage to patient sensitivity as well as pain intensity. In addition a capnograp h and oximeter provide direct monitoring of the patient's state and allow for a larger range of adaption.