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Objective: To study the efficacy of intramuscular midazolam in treating seizures. Design: On arrival, patients with seizures were treated with intramuscular midazolam, a stopwatch was started, and an intravenous line inserted. If the seizure had not stopped within six minutes, standard intravenous anticonvulsants were given. The time to cessation of the seizure was recorded. Setting: Department of Emergency Medicine, Fremantle Hospital, a busy emergency department (50,000 annual attendances, 18% children) in a general community teaching hospital. Main outcome measure: Time to cessation of fitting. Results: Thirty eight patients aged from 15 months to 89 years, were treated with intramuscular midazolam at an average dose of 0.12mg/kg (range 0.07–0.21mg/kg). The seizures terminated in all but two cases in an average time of 1minute 53 seconds overall (range 15 seconds to 6 minutes 7 seconds). In a subgroup of 15 patients with prolonged seizures of 36 minutes duration on average, the seizures ceased in a mean time of 2 minutes 41 seconds, with one failure. The latter time is likely to represent the true response time of seizures to intramuscular midazolam as some of the short‐lived seizures may have ceased spontaneously. All seven children treated with intramuscular midazolam ceased fitting. There were no adverse side effects in any patient. Conclusion: Midazolam given by intramuscular injection was shown to be rapidly effective for the control of generalised convulsive seizures, focal seizures and status epilepticus in adults and in children. This new therapy has exciting applications in the treatment of seizures in children and in the pre‐hospital setting. 1992 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine

At Curtin University of Technology, all final-year undergraduate surveying students must take a field-to-finish survey camp as part of their degree programme. This paper outlines the six exercises now set and their educational rationale, including a novel system where a production environment is replicated by setting penalties for late submission of assignments. In addition, some deliberate 'traps' are set to reinforce routine checks of their observations. The approaches and philosophies used here may be of use/interest to other field-surveying educators.

The former Portuguese colony of East Timor was forcibly absorbed into the Republic of Indonesia in 1975. An armed East Timorese resistance movement maintained a fight for independence for the next quarter of a century. The Indonesian Government allowed a plebiscite of the population in August 1999, the result of which was strongly in favour of independence. Following the poll, there was an outbreak of extreme violence and the structure of the country was virtually destroyed. The Indonesian Government invited a multinational force to restore order. This report is of the medical work conducted while serving in a multifunction non-government organization in East Timor in the post-conflict environment. The work includes developing a tuberculosis clinic, conducting refugee medicine at the border crossing point and establishing a rudimentary health-care system based on a primary-care model. A background in emergency medicine is very useful in situations such as this, where improvisation becomes a core skill.

Seventy‐five consecutive patients attending the Emergency Department at Fremantle Hospital in status epilepticus were treated with intravenous midazolam. All seizures ceased without other therapy, after an average dose of 0.1 mg/kg midazolam. Seven percent of patients had a further seizure in the Emergency Department, a rate comparable to other anticonvulsants. Midazolam is a safe, effective agent for the treatment of status epilepticus, with possible advantages over currently accepted treatment. 1992 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine

The first defence of the America's Cup outside of the USA took place off Fremantle, Western Australia, between October, 1986 and February, 1987. Fremantle Hospital, the nearest hospital to the marinas, was involved in the planning for disasters and for the provision of clinical services to the syndicates involved and the projected crowds of tourists and spectators. The impact of this unique sporting event on the hospital was measured by collecting data from all patients whose presence in Fremantle was related to the yachting. The America's Cup resulted in only 654 attendances and 31 admissions over the 5 months of the event. The figures fell far short of those predicted. A number of conclusions have been drawn.

The conductance of Au-doped Si single crystals was measured during irradiation with 30-nsec $Q$-switched ruby-laser pulses at energy densities above the Si melting threshold (\ensuremath{\sim}0.9 J/${\mathrm{cm}}^{2}$). The sample conductance is determined primarily by the thickness of the molten layer so that the solid-liquid interface velocity can be found from the current transient. The interface velocity during crystallization was found to be 2.7\ifmmode\pm\else\textpm\fi{}0.1 m/sec, in close agreement with calculated values based on a heat-flow model.

The reactions of metals with GaAs are substantially more complex than comparable metal‐silicon systems. In this paper, phase formation in the Co‐GaAs system is examined in detail and contrasted with other metal‐GaAs and metal‐silicon systems. Both elemental and microstructural characterization techniques are used, and the limitations of each are discussed. Cobalt begins to react with GaAs at 375 °C and initially forms a ternary phase of approximate composition, Co2GaAs. Subsequent reactions or higher‐temperature annealing results in the formation of binary phases CoGa and CoAs. The observed phase formation is controlled by the species with the largest diffusion coefficient, and this species is determined by the temperature. At sufficiently high annealing temperatures, arsenic is lost from the surface, and an epitaxial CoGa phase is formed on the GaAs.

Midazolam meleate, a water soluble 1,4 benzodiazepine, was used intravenously in 20 patients suffering seizures, of whom 12 were in status epilepticus. In all cases, midazolam in a dose of 2.5-15 mg rapidly terminated the seizure. There were no complications from the use of midazolam. The causes of the seizures were varied but alcohol-withdrawal seizures were the single largest cause. Thirteen patients were taking some form of anticonvulsant medication but only three were in the therapeutic range. Midazolam is seen to be an effective agent in the emergency treatment of seizures.

Measurements during pulsed laser irradiation indicate that amorphous Si melts at a temperature 200 \ifmmode\pm\else\textpm\fi{} 50 K below the crystalline value. Below energy densities required to melt the amorphous layer fully, the data are interpreted in terms of an explosive crystallization. The initial liquid layer solidifies to form coarse-grained polycrystalline Si. A thin, self-propagating liquid layer travels through the remaining amorphous Si at a velocity of 10-20 m/s, producing fine-grained polycrystalline Si.

The paper describes an instrument that fills a gap in the range of viscometers available in a lubrication research laboratory, namely a viscometer that covers a wide range of rate of shear at ambient pressures substantially above atmospheric and at various temperature. It is a capillary viscometer in which a selected flow rate is maintained steady and the pressure drop between entrance and exit is measured. The direction of floe can be reversed. Corrections are applied for inertial effects, viscous self-heating and pressure effects. The correction procedures are described and some experimentals results are given for a polymer-containing oil. The instrument has been operated at isotropic pressure up to 0.2 GPa, rates of shear up to 2X105 s−1 and temperature between 20 and 100°C. In principle, it should be possible to extend these ranges.

Observation wards have not been discussed in the Australian literature. In the United Kingdom, the few published reports suggest that they are an essential part of the function of emergency departments. This paper presents the results of a survey of 44 major Australian hospitals regarding their use of observation wards. Half the hospitals that were surveyed had such wards but variations existed in the way that they functioned. Nearly half the remaining hospitals wanted to establish an observation ward. Our concept of observation wards is discussed.

The dynamics of silicon solidification from the melt during pulsed-ruby-laser annealing have been investigated with the use of time-resolved electrical-conductance and optical-reflectance measurements. Melt duration was found to increase with laser-energy density to over 450 nsec at the highest energy used (3.1 J/${\mathrm{cm}}^{2}$). Resolidification velocity was found to vary with time and laser-energy density over a range of 2 to 3 m/sec. The melt threshold was observed to be 0.8 J/${\mathrm{cm}}^{2}$. Measurements of the laser energy absorbed in the sample were made to determine energy coupling parameters for use in numerical calculations. The numerical calculations, based on a thermal model for laser melting, are found to be in good agreement with the experimental results.

Recent advances in the theory of elastohydrodynamic lubrication have greatly increased the demand for information on the physical properties of lubricants at high pressures. Specifically, the viscosity and density and their variation with temperature and pressure enter directly into calculations of the behaviour of lubricants in loaded contacts, whilst for some experimental techniques the dielectric constant at the appropriate conditions is also required. This paper presents measured values of viscosity at pressures up to 15 000 lb/in2 at 30°, 60° and 100°C, and of density and dielectric constant at pressures up to 50 000 lb/in2 at 20° and 100°C for a series of lubricants including mineral, vegetable and synthetic oils. The use of the Clausius-Mosotti relationship to predict dielectric constants at high pressures is shown to be unsatisfactory, and this is demonstrated by application to capacitance measurements obtained in a disc machine.

As the first part of a programme in which the properties of lubricants under conditions encountered in the elastohydrodynamic régime will be measured, a low-shear-rate viscometer operating at pressures up to 120 000 lb/in2 has been constructed. It is of the falling body type in which the time of fall under gravity of a hemispherically ended cylindrical sinker through the test fluid is measured. The relationship between viscosity and fall time is of the form: A major correction is applied for the effect of pressure on the density of the fluid and a smaller one for the changes in dimensions of the viscometer under pressure. A means of measuring the change of density of the fluid is incorporated in the viscometer.

We review the difficulties encountered in the design and operation of apparatus for rheological studies on liquids at pressures up to 900 MN m−2 and temperatures from −30 to 120°C. Such rheological information is required in connection with elastohydrodynamic lubrication in which high pressures and shear rates are encountered.

British aerodynamic gas-bearing gyros of the highest precision for use in Naval equipment are required to have long durability of low starting friction for the brief periods of rubbing contact before the rotor becomes gas-borne. Start failures in service have caused the Navy Department to initiate a two-phase programme of investigation and research into the problem. The first phase, intended to enable production to continue and reasonable performance to be obtained, is reported in references [1, 2]. The second phase, described herein, has been of a more fundamental nature and has been intended to amend hitherto empirical processes to a sound scientific basis and to gain understanding of bearing surface behavior. The paper describes trials and results of experiments carried out jointly by Admiralty Compass Observatory and Shell Research Ltd. on various aspects of bearing cleaning, boundary-lubricant behavior, and bearing surface materials. Glow discharge cleaning, examined by radiotracer technique, has been found to be very much more efficient than organic solvents, as well as permitting a big reduction in process time. Proposals for a simplified and more effective cleaning process and for boundary lubrication with a fatty acid are given. Examinations of surface films by friction machine, radiotracer techniques, electron diffraction, and ellipsometry have established that chemical bonding occurs between bearing surfaces and boundary lubricant and have enabled film thicknesses of molecular proportions and molecular orientations to be determined. Preliminary work is reported on the effects of processes described on ceramic bearing materials.

Transient electrical conductance measurements have been made on 0.45‐μm silicon‐on‐sapphire during pulsed laser annealing with 25‐ns ruby irradiation. The photoconductive contribution to the transient current was sufficiently small that the entire melt and resolidification process could be directly observed. The technique yields quantitative measures of melt depths, melting velocities (5–13 m/s), and solidification velocities (2.8–3.3 m/s). Combined with the complementary techniques of time‐resolved reflectivity, energy transmission, and calorimetric energy absorption, transient conductance provides a powerful new diagnostic for investigating melt dynamics.

Solid phase epitaxial growth of electron beam deposited amorphous germanium on GaAs has been obtained. Contamination at the Ge/GaAs interface is observed to impede and even prevent epitaxy of the deposited Ge layer. Complete epitaxy of the Ge was obtained by thermal annealing (400 °C for 1 h) of layers deposited on in situ sputter cleaned GaAs substrates.

The solid state reaction between a Co thin film and (100) GaAs was investigated using Rutherford backscattering spectrometry. At 400 °C a reacted layer of composition Co:Ga:As=2:1:1 was observed to form. This reaction product obeys diffusion controlled growth kinetics and maintains its composition for annealing (400 °C) from 15 min up to 24 h.

The measured solidification velocities in silicon after pulsed laser melting are analyzed in terms of thermodynamic and kinetic considerations. Both interface and thermal transport limited growth regimes are observed. From the observed kinetics in the 1–6‐m/s regime, the undercooling at the liquid‐solid interface can be calculated. At velocities ≤6 m/s the undercooling increases with interface velocity at the rate of 15±5 deg/m/s.

Energetic ion beams used outside the traditional role of ion implantation are considered for semiconductor applications involving interface modification for self-aligned silicide contacts, composition modification for formation of buried oxide layers in Si on insulator structures and reduced disorder in high energy ion beam annealing for buried collectors in transistor fabrication. In metals, aside from their use in modification of the composition of near surface regions, energetic ion beams are being investigated for structural modification in crystalline to amorphous transitions. Pulsed beams of photons and electrons are used as directed energy sources in rapid solidification. Here, we consider the role of temperature gradients and impurities in epitaxial growth of silicon.

Energy deposition and heat-flow determine the temperature distributions in pulsed-beam irradiated structures. In laser irradiated Si, transient conductance measurements indicated a liquid/solid interface velocity of 2.8 m/sec during crystallization in agreement with a heat flow model. With pulsed ionbeam annealing of metal-Si structures, melting starts at the interface; epitaxial NiSi2 layers have been formed. Ion-beammixing experiments on polycrystalline and epitaxial Au-Ag bilayers show that intermixing is more pronounced in the polycrystalline structures as is the case with thermal annealing. Superlattice structures are formed in the epitaxial structures.

High intensity pulsed laser irradiation of semiconductor materials results in ultra-fast melting and resolidification of a thin surface layer. An experimental probe has been developed based on the discontinuous change in electrical conductivity of a semiconductor material upon melting. Real time monitoring of the dynamics of pulsed laser melting and resolidification can be obtained by transient electrical conductance measurements. Melting velocities from 5 to 200 m/s and resolidification velocities of 1 to 20 m/s have been observed in silicon with this technique. Simultaneous measurement of the optical reflectance provides additional complementary information on laser melting dynamics. Data from both electrical conductance and optical reflectance measurements are presented for silicon and gallium arsenide. The real time experimental data provide strong evidence for a simple thermal model for melting and resolidification during nanosecond pulsed laser annealing.

Measurements were made of the conductance of single crystal Au-doped Si and silicon-on-sapphire (SOS) during irradiation with 30 nsec ruby laser pulses. After the decay of the photoconductive response, the sample conductance is determined primarily by the thickness and conductivity of the molten layer. For the single crystal Au-doped Si, the solid-liquid interface velocity during recrystallization was determined from the current transient to be 2.5 m/sec for energy densities between 1.9 and 2.6 J/cm2, in close agreement with numerical simulations based on a thermal model of heat flow. SOS samples showed a strongly reduced photoconductive response, allowing the melt front to be observed also. For complete melting of a 0.4 μm Si layer, the regrowth velocity was 2.4 m/sec.

Transient electrical conductance has been used to measure the resolidification velocity in silicon containing implanted solutes. Nonequilibrium segregation of the solutes occurs during the rapid resolidification following pulsed laser melting. The velocity of the liquid-solid interface is observed to depend on the type and concentration of the solute. A 25% reduction in solidification velocity is observed for an implanted indium concentration of three atomic percent. Implanted oxygen is also shown to reduce the solidification velocity. The dependence of the velocity on solute concentration impacts a variety of segregation, trapping and supersaturated solution studies.

Solid phase epitaxial growth of electron beam evaporated Ge layers on unheated GaAs has been demonstrated. The amorphous Ge layers grow epitaxially on the GaAs surface during anneals at 400°C. A technique for growing these epitaxial layers without the need for in-situ heat treatment of the GaAs prior to Ge deposition is described.

The transient conductance technique has been used in a detailed study of the liquid-solid interface dynamics during pulsed laser melting of Si and silicon-on-sapphire. Average melt and regrowth velocities, as well as the maximum melt depth, can be obtained with the technique. The measurements are found to agree well with a computer simulation based on a thermal model of the melt and subsequent solidification. The melt-in velocity has been observed to exceed 200 m/sec. Under 2.5 ns UV irradiation, the critical velocity for amorphization of Si has been measured at 15 m/sec.

COMPOUNDS of sulphur, phosphorus, zinc and chlorine are added to lubricating oils to control wear under arduous conditions by forming films on rubbing surfaces. The films are extremely thin and frequently amorphous. Only rarely has it been possible to identify compounds present although electron probe microanalysis can show the distribution of elements. We here present new information, obtained from electron spectroscopic measurements, mainly concerning the binding energies of photoelectrons (ejected with AlKα X rays) the magnitudes of which are characteristic of particular atoms and electrons, and which may therefore be used for analytical purposes. We also made some observations of the kinetic energies of Auger electrons, which are also well defined and of analytical value. These energies depend on the charge on the atom, so that for states of combination of an element where the charges on the atoms are sufficiently different, valuable ‘chemical shifts’ are observed; sulphur is a favourable case with a shift of about 6 eV from sulphide to sulphate. Only electrons that escape without collision are of value, so the analysed depth was limited to a few tens of A, the region of interest in lubrication.