526 research outputs found

    Staphylococcus food poisoning: recommendations for its prevention and control

    Get PDF
    Mr. Dewberry, a Fellow of the Society of Health and of the Institute of Public Health and Hygiene, served with The historic Mediterranean Fever Commission in Malta in 1904-05 and may be the last survivor of that celebrated group. In this article he puts forward several recommendations for the prevention and control of staphylococcus food poisoning. Staphylococcus bacterium is commonly found in nature and the organisms are widespread among healthy persons, being present on the skin, in the throat and in the nasal passages. In the majority of the outbreaks occurring in England and Wales due to the enterotoxin, the incriminated vehicle has been a protein foodstuff (meat), which has been cooked the day previous to its being consumed. There appears to be only one effective way of controlling this type of food poisoning and that is to prevent pathogenic staphylococci from producing the enterotoxin in cooked protein foods. In this regard, guidance in treating stored food, including the maximum temperatures at which to keep cold or hot cooked protein foods is provided. In essence, since enterotoxin is odourless, colourless and tasteless, one cannot depend on the appearance, taste or smell of cooked protein food.peer-reviewe

    Do consensus meetings undermine the validity of assessment centres?

    Get PDF
    In this study the effects of latent-informal processes operating in assessment centre consensus meetings is investigated with a combination of qualitative and quantitative methods. Non-participative observation is carried out in several consensus meetings, and auditory recordings made in three of these. In an analysis of the transcript of a consensus meeting in one organization, evidence is found for several latent-informal processes. These include active attempts by assessors to persuade other assessors, and the group facilitator, to appoint candidates; the use of assessorsтАЩ general impressions of candidates in this persuasion process; and the active use of power derived from an assessorsтАЩ relative seniority in the organization. Evidence consistent with the use of seniority-derived power is also found in a quantitative analysis of the selection decisions made in consensus meetings about 413 candidates. The results of the study are considered in relation to the practical utility of consensus meetings, and it is concluded that the use of such meetings is difficult to justify

    The environmental control and life support system advanced automation project. Phase 1: Application evaluation

    Get PDF
    The Environmental Control and Life Support System (ECLSS) is a Freedom Station distributed system with inherent applicability to advanced automation primarily due to the comparatively large reaction times of its subsystem processes. This allows longer contemplation times in which to form a more intelligent control strategy and to detect or prevent faults. The objective of the ECLSS Advanced Automation Project is to reduce the flight and ground manpower needed to support the initial and evolutionary ECLS system. The approach is to search out and make apparent those processes in the baseline system which are in need of more automatic control and fault detection strategies, to influence the ECLSS design by suggesting software hooks and hardware scars which will allow easy adaptation to advanced algorithms, and to develop complex software prototypes which fit into the ECLSS software architecture and will be shown in an ECLSS hardware testbed to increase the autonomy of the system. Covered here are the preliminary investigation and evaluation process, aimed at searching the ECLSS for candidate functions for automation and providing a software hooks and hardware scars analysis. This analysis shows changes needed in the baselined system for easy accommodation of knowledge-based or other complex implementations which, when integrated in flight or ground sustaining engineering architectures, will produce a more autonomous and fault tolerant Environmental Control and Life Support System

    Space Station Freedom ECLSS: A step toward autonomous regenerative life support systems

    Get PDF
    The Environmental Control and Life Support System (ECLSS) is a Freedom Station distributed system with inherent applicability to extensive automation primarily due to its comparatively long control system latencies. These allow longer contemplation times in which to form a more intelligent control strategy and to prevent and diagnose faults. The regenerative nature of the Space Station Freedom ECLSS will contribute closed loop complexities never before encountered in life support systems. A study to determine ECLSS automation approaches has been completed. The ECLSS baseline software and system processes could be augmented with more advanced fault management and regenerative control systems for a more autonomous evolutionary system, as well as serving as a firm foundation for future regenerative life support systems. Emerging advanced software technology and tools can be successfully applied to fault management, but a fully automated life support system will require research and development of regenerative control systems and models. The baseline Environmental Control and Life Support System utilizes ground tests in development of batch chemical and microbial control processes. Long duration regenerative life support systems will require more active chemical and microbial feedback control systems which, in turn, will require advancements in regenerative life support models and tools. These models can be verified using ground and on orbit life support test and operational data, and used in the engineering analysis of proposed intelligent instrumentation feedback and flexible process control technologies for future autonomous regenerative life support systems, including the evolutionary Space Station Freedom ECLSS
    • тАж
    corecore