Voluntarism: is it a useful concept for health education in the accident and emergency department?

As the year 2000 looms closer, the emphasis on health education as a means of attaining the 38 targets for 'Health for All' increases. Despite various initiatives, little, if any, progress has been made in narrowing the health divide. Currently, terms such as 'self-care', 'individual responsibility' and 'community empowerment' are often used with emphasis on individual freedom to choose. The author contends that to assume all individuals have that freedom and act voluntarily, is to deny the impact of social structure on health. Health education and the concept of voluntarism will be critically examined from the perspective of nursing in an accident and emergency department.     

A test piece for mechanical testing of fiber composite materials

This article describes a test piece that minimizes the spread of the results of testing of composite materials on a metal base by extension in the direction of a reinforcing fiber and, from the results, determines the mechanical properties of intermediate and finished products made of these materials.Translated from Izmeritel'naya Tekhnika, No. 10, pp. 39–40, October, 1993.     

Nontuberculous mycobacteriosis as a complication of the Swyer-James syndrome

The chest radiograph of a 35-year-old man with fatigue, exertional dyspnoea and haemoptyses revealed a cavity in the left upper lobe and a shrunken left lung with radiolucency greater than that on the right. Acid-fast rods in sputum were identified as Mycobacterium kansasii on culture. Scintigraphy showed a 9% residual perfusion on the left and abnormal ventilation, compatible with Swyer-James syndrome. This had favoured the development of a mycobacterial infection. There was also a decrease in ciliary function (rate of 4-7 Hz, normal: 10-11). Treatment, begun when tuberculosis had been suspected, was after sensitivity tests changed to a combination of rifampicin (600 mg), ethambutol (1600 mg) and protionamide (500 mg) daily. There was marked regression of the findings within 4 weeks, but treatment was prematurely stopped after 11 months. Two years later there was a recurrence which again responded well to the same drug regimen with additional sulphamethoxazole (1600 mg/d).     

Nonlinear oscillations of a vapor bubble in the region of the main resonance

Nonlinear spherical vapor bubble oscillations in the main resonance region in a viscous incompressible fluid under the action of a periodically varying external pressure are considered using the multiscale method. Saddle-node type bifurcations that appear when the amplitude or frequency of the external effect changes are investigated.Institute of Thermal Physics of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 2, pp. 164–170, August, 1993.     

Microstructure study of Sm,Mn-modified PbTiO3 piezoelectric ceramics by XRD profile-fitting technique

By using the X-ray diffraction profile-fitting technique, the microstructures of Sm, Mn-modified PbTiO₃ piezoelectric ceramic discs, including ferroelectric domain sizes, microstrains, and their variations with the poling strength have been quantitatively investigated. The results manifest that the modified PbTiO₃ ceramics contain a high density of domain walls due to the presence of finely-divided coherent domain structures (tens of nanometres in dimension). The poling treament can evidently influence the domain-size distribution, with a more homogeneous microstructure being developed; however, it simultaneously causes high anisotropic microstrains within the structure which, together with the high density of domain walls, is expected to be responsible for the unusual high electromechanical coupling properties possessed by this material.     

Development of an octocalcium phosphate cement

From previous studies it is known that alpha-tertiary calcium phosphate and dicalcium phosphate form a cement upon mixing with water. In this study this cement was optimized in terms of the milling of the constituents, their molar ratio, the amount of hydroxyapatite added and the water/powder ratio. The optimum Ca/P molar ratio of the cement mixture was 1.36±0.03. X-ray diffraction showed the reaction product to be octocalcium phosphate. Addition of precipitated hydroxypatite of over 3% diminished the final strength of the cement significantly. However, admixtures of only 2% of precipitated hydroxyapatite (a) kept the final compressive strength at 30±5 MPa after soaking in Ringers solution at 37°C, (b) diminished the initial setting time from 27.5 to 10 min and the final setting time from 65 to 40 min, (c) diminished the time in which the final strength was reached from 36 to less than 14 h. The tensile strength of this cement is 19±1% of its compressive strength. The optimum water/powder ratio as found in this study was 0.30 g/g.     

Limitations and benefits of cooperative proxy caching

Cooperating proxy caches are groups of HTTP proxy servers that organize to share cached objects. This paper develops analytical models for proxy cooperation which use speedup in user response time as the performance metric. Speedup expressions are derived for the cooperation upper bound, a proxy mesh, and a three-level proxy hierarchy. The equations compare fundamental design approaches by separating the proxy organization for object delivery from the mechanism for object discovery. Discovery mechanisms analyzed for the mesh and hierarchy models include ideal discovery, Internet cache protocol (ICP) query, and distributed metadata directories. Equations are evaluated using parameter estimates from experiments and from analysis of cache trace logs. Results indicate that proxy cooperation is marginally viable from the standpoint of average user response time, and that the miss penalty for the hierarchy renders it less viable than the mesh. Proxy cooperation can, however, reduce the variability in user response time and the number of long delays. A trace-driven simulation shows that caching constraints have little effect on cooperation performance due to request filtering by lower level caches.     

Control Mechanisms in Network Structures

Formulation of the problem of designing the optimal structure of an active system was considered within the framework of the game-theoretical model of interaction of its participants. Solution and the results of studying the control mechanisms in applications such as in-house management and multiagent systems were presented.     

Relation between abrasion resistance and flexural strength of high volume fly ash concrete

In this paper, abrasion of high volume fly ash (HVFA) concretes made with 50% and 70% of cement replacement with fly ash was assessed in terms of its relation to flexural tensile strength. Comparisons were made between normal Portland cement (NPC) concrete and fly ash concrete. Comparisons were also made between fly ash concretes. Investigation results have shown that the abrasion resistance increased as flexural tensile strength increased. Analysis of the results showed that, for concrete with tensile strength of greater than 4–5 MPa, the abrasion resistance of HVFA concrete with 70% replacement with cement was found to be higher than that of counterpart control NPC concrete and concrete made with 50% fly ash. The comparison between the relation of abrasion to compressive strength and abrasion to flexural tensile strength made in terms of R² of the linear regression showed that a stronger relation existed between abrasion and flexural tensile strength than that of abrasion to compressive strength of the concrete studied.

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Résumé L'étude a pour but d'estimer la relation entre la résistance à l'usure avec la résistance à la traction en flexion des bétons contenant de 50% et 70% de cendres volantes. On a comparé le béton pur au béton contenant des cendres volantes. Des comparaisons ont été faites également entre les différents bétons contenant des cendres volantes. Les resultats de la recherche ont montré que la résistance à l'usure augmente à mesure que la résistance à la traction en flexion de 4∼5 MPa ont une résistance à l'usure plus grande s'ils contienneint 70% de cendres volantes que s'ils étaient purs ou contenaient 50% de cendres volantes. La comparaison entre les relation de la résistance à l'usure en compression et de la résistance à l'usure en traction a été établie en termes de R² de la régression linéaire. On a prouvé qu'une relation plus forte a été obtenue entre la résistance à l'usure et la résistance à la traction en flexion par rapport à la résistance à l'usure en compression du béton étudié.