Advanced manufacturing technology and work design: Towards a theoretical framework

This paper introduces a theoretical framework to guide research into the psychological effects of advanced manufacturing technology (AMT) on shopfloor operators. The framework has two main aspects. First, based on the emerging literature on the job content implications of AMT, it identifies four key constructs, namely: control, cognitive demand, production responsibility and social interaction. Second, by drawing on the more established job design, stress and related literatures, it predicts how these independent variables differentially affect system performance, job-related strain and job satisfaction. The wider implications and limitations of the theoretical framework are discussed.     

Utilization of prenatal cytogenetic diagnosis in women of advanced maternal age in Australia, 1979–1982

This paper reports the results of a complete national survey to measure utilization rates of prenatal cytogenetic diagnosis (P.C.D.) in women of advanced maternal age in Australia. P.C.D. has been available throughout Australia for the last decade. Every laboratory in Australia providing a P.C.D. service for the years 1979–1982 took part in this study. Utilization rates (both National and State rates) by ages of mothers, are presented. Big interstate differences exist. The 1982 National P.C.D. utilization rate for pregnant women who were 40 years of age and over was 38.8 per cent, and this rate has shown an average annual increase of 9 per cent. In those four States which offered P.C.D. to pregnant women of 35 years or over the median utilization rate was 20 per cent. These Australian rates indicate an under-utilization of P.C.D. services with (in 1982) 50–80 per cent of ‘at risk’ women not being tested. Factors which influence this are discussed.     

Ventilation efficiency

Research indicates that ventilating systems can be designed for higher ventilation efficiency in the zone of occupation than systems designed for complete mixing. Expressions for ventilation efficiency are derived using a two-box theoretic model. These definitions of ventilation efficiency can be used for practical measurements, and also seem to be valid for multibox schemes. Measurements reviewed show that diagonal schemes are the most efficient. Short-circuiting schemes, with warm air supply along the ceiling and high wall exhaust, produce very low efficiencies. The mathematical model predicts high efficiencies using diffuse air supply directly to the zone of occupation, if the air is not used heating.     

东非十足类螃蟹迈纳新胀蟹对红树林海底落叶的清理

本文通过在东非进行的一系列野外和实验室试验,研究了丰富的红树林十足类螃蟹迈纳新胀蟹(Neosarmatium meinerti)对落叶的清理.在地势高的海榄雌(Avicennia meinerti)潮间带,螃蟹掩埋了所有红树林林区海底的落叶,而且会在2小时内平均消耗其中的67%.     

Visual fields in Flamingos: chick-feeding versus filter-feeding

In birds, the position and extent of the region of binocular vision appears to be determined by feeding ecology. Of prime importance is the degree to which vision is used for the precise control of bill position when pecking or lunging at prey. In birds that do not require such precision (probe and filter-feeders), the bill falls outside the binocular field, which extends above and behind the head, thus providing comprehensive visual coverage. Flamingos Phoenicopteridae are highly specialised filter-feeders. They employ a unique technique that does not require accurate bill positioning in which the inverted head is placed between the feet. Feeding flamingos often walk forwards with the head pointing “backwards”. Here we show that in Lesser Flamingos Phoeniconaias minor visual fields are in fact the same as those of birds that feed by precision pecking and that feeding flamingos are blind in the direction of their walking. We suggest that this is due to the requirement for accurate bill placement when flamingos feed their chicks with “crop-milk”, and possibly when building their nest. We propose that chick-feeding may be the ultimate determinant of visual field topography in birds, not feeding ecology.     

Initiale Aktivität und Willkürverhalten bei Tieren

Initiation as a basic property of behavioral activity is functionally analyzed and discussed at the level of voluntary behavior. Fixed action patterns often are not released by stimuli but are generated by the animal itself through brain processes of the Darwinian type. Analogous to mutations, behavioral “subroutines” are brought up by chance and are subjected to selection either by the change in the situation (trial and the elimination of error) or by mental activity suppressing inappropriate behavior even before it is executed.Initiation improves the chance of survival. It is a prerequisite of goal-oriented behavior, an essential constituent of operant conditioning and presumably the first step in the evolution of thought. According to I. Kant a person is free if, by following his own directive, he does what has to be done. This definition meets the two central criteria of initiation: the independence of releasing stimuli and the adaptive value of the behavior generated.