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A study of current design practices was conducted to identify organizational and design process differences influencing the use of ergonomic information in manual workspace design. Significant differences regarding the design information sources and objectives existed between preliminary, or division-level, and detailed, or plant-level, design activities. Ergonomic concerns, e.g., health and safety factors and operator feedback, were most clearly present in plant-level design; unfortunately, plant designers also had the least flexibility, in terms of design parameters to vary, and dollars to spend, to retrofit inadequate designs. Results indicate specific factors, (such as designer temporal and geographic proximity to the design implementation), to consider during the development of an effective industrial ergonomics training program.

EDGE is a computer-based ergonomic workspace design system which integrates several models of operator performance with a common graphic interface. In addition to serving as a practical design system, it also serves as a research tool for understanding the ergonomic design process in industry. System users include trained ergonomists and engineers responsible for manual workspace design. The design system centers around a core vocabulary of task-related terms. A common input format, modeled after the traditional “work methods table” addresses the input requirements of the varied human performance models. Output from the performance models is displayed on multiple screens in varying levels of detail. Among the measures of physical stress currently integrated into the system are models of biomechanical strength, NIOSH lifting limits, metabolic energy expenditure, and elemental time prediction.

Efforts to streamline office processes have, in the past, concentrated on augmenting clerical tasks through automated word processing and document preparation technologies. More recently, the needs for improved office productivity have directed productivity boosting technologies at managers and their jobs. This paper presents concepts of managerial productivity within the framework of evolving managerial roles in the changing office environment. Areas where office technologies could augment managerial activities and several socioeconomic considerations for the implementation of new technologies are also discussed.

The paper describes an investigation of the effects of computer-based training (CBT) delivery methods on learning and retention in target recognition and identification tasks. Two training methods (drill and practice, and branching computer aided instruction) were administered to subjects at two locations. Measures of cognitive complexity also were obtained on each subject and compared against test scores. Results confirmed that learning did occur with both CBT methods. Results also suggest that training design is not straightforward, and must consider a number of student and training site factors as well as the topic to be trained. Trends, while not highly significant, do suggest directions for further research.

A research project was conducted to identify current industrial workspace design practices, especially regarding the consideration paid to the human operator in manual workspaces, and to develop an approach for presenting ergonomic information to designers in formats conducive to the design process. Specific operator physical-stress-related performance factors considered in this research include strength capabilities, reach feasibility, and movement times. The paper presents selected results of a survey of 40 engineers/designers, and outlines the criteria for a computer-aided ergonomic design system for manual workspace design.

A heterologous radioimmunoassay for tammar wallaby FSH, using an ovine FSH antiserum and a human FSH tracer, is described. With this assay concentrations of FSH in plasma of intact female tammars are not detectable except rarely at the time of oestrus. However the assay has proved useful in studies of the control of gonadotrophin secretion in intact male and in ovariectomized tammars.In the female tammar, concentrations of LH and FSH in plasma rose within a few days of bilateral ovariectomy. Ovariectomized tammars respond to a luteinizing hormone releasing hormone stimulus (10 μg, i.v.) with a prompt release of LH, peak levels of 16·9 ± 1·4 ng NIH-LH-S19/ml plasma (n= 12) being reached within 25 min of injection. Concentrations of LH and FSH in plasma were reduced to preoperative values in ovariectomized tammars when lutein tissue developed in ovarian cortex grafts autotransplanted under the pouch skin. Ovarian interstitial tissue was not necessary for this effect.After lutectomy during quiescence, the female tammar ovulates again in about 14 days. Injections of progesterone (700 μg/kg per day, i.m.) for 7 days after the operation did not delay this response, but follicular development and ovulation appeared to be retarded in animals given oestradiol-17β (5 μg/kg per day, i.m.) with or without progesterone.

A heterologous double antibody radioimmunoassay employing a rabbit anti-ovine LH antiserum (GDN no. 15) has been developed for the assessment of concentrations of LH in macropodid marsupial pituitary extracts and plasma. In this radioimmunoassay system highly purified ovine, rat, human and kangaroo LH preparations demonstrated apparently parallel dose–response curves, as did serial dilutions of crude pituitary extracts from a wide range of Australian marsupial species and serial dilutions of plasma from ovariectomized, oestrous and LH releasing hormone (LH-RH)-treated marsupials. The assay has been used to monitor changes in immunoreactive LH in the plasma of the female tammar wallaby. Basal concentrations of LH in non-oestrous female wallabies were in the range < 0·20–1·90 ng/ml with many animals having values at or near the limit of detection of the assay. Concentrations of LH were markedly increased following ovariectomy (1·7–7·0 ng/ml), on the day of oestrus (10·0–> 50 ng/ml) and following administration of LH-RH (9·5–> 25·0 ng/ml). Plasma from hypophysectomized animals had no detectable LH immunoactivity, A well-defined LH surge, lasting approximately 12 h, was associated with oestrus. Mating occurred approximately 8 h before, and ovulation approximately 24 h after, the maximal concentration of LH in plasma.

1. The effect of biologically synthesized and purified fluorocitrate on the metabolism of tricarboxylate anions by isolated rat liver mitochondria was investigated, in relation to the claim by Eanes et al. (1972) that this fluoro compound inhibits the tricarboxylate carrier at concentrations at which it has little effect on the aconitate hydratase activity. 2. That the inhibitory action of fluorocitrate is at the level of the aconitate hydratase and not at the level of the tricarboxylate carrier is indicated by the following findings. Although the oxidation of citrate and cis-aconitate, but not that of isocitrate, was inhibited by fluorocitrate, the exchange of internal citrate for external citrate or l-malate was not. Had the tricarboxylate carrier been affected, these latter exchange reactions would have been inhibited. 3. By using aconitate hydratase solubilized from mitochondria it was found that with citrate as substrate the inhibition by fluorocitrate was partially competitive (Ki=3.4×10−8m), whereas with cis-aconitate as substrate the inhibition was partially non-competitive (Ki=3.0×10−8m).