W De Corte

High contrast sets of colours for colour CRTs under various conditions of illumination

Abstract The Carter and Carter algorithm to compute high-contrast sets of colours is extended to cope with the presence of ambient illumination. Several application results are graphically represented in the CIE 1931 and the CIE 1976 colour triangle. A simulation study, based on the new algorithm, further investigates the effects of illumination strength (I), type of ambient (A), phosphor type (P), and number of displayed colours (N) on the possibility of generating discriminable colours. The limitations of the present methodology with regard to the definition of ergonomically optimal colours are also discussed.

EPIDEMIOLOGY OF AKI IN THE ICU

Abstract Up to a little while ago there was no uniform definition for acute kidney injury (AKI). Recently, the Acute Dialysis Quality Initiative proposed the RIFLE consensus classification for AKI. This classification was adapted and modified by the Acute Kidney Injury Network into the AKI staging system. This classification defines 3 stages of severity of AKI, including less severe AKI. The incidence of AKI in ICU patients is increasing; severe AKI, treated by renal replacement therapy (RRT), has now an incidence comparable to that of acute lung injury/acute respiratory distress syndrome (ALI/ARDS), and less severe AKI has an incidence comparable to that of sepsis. The prognosis of patients with AKI treated with RRT is still dim, with mortality rates between 50% and 60%. It is important to know that AKI is not only a consequence of severe disease, but also contributes to its worse outcome. Severe AKI, and less severe AKI, as defined by the AKI classification, have an independent association with mortality.

Recent developments in the computation of ergonomically optimal contrast sets of CRT colours

Abstract A new algorithm, for the computation of high contrast sets of colours, is presented. Compared to existing analytic procedures, the new COLOUR algorithm is superior in conceptual, technical and practical respects. The versatility of the program is illustrated on a well-known problem concerning the specification of an optimal colour set for an airborne display. Other issues, related to the practical utility of the method, are also discussed.

Randomized clinical trial on the influence of anaesthesia protocol on intestinal motility during laparoscopic surgery requiring small bowel anastomosis

Hyperperistalsis of the small bowel during laparoscopic surgery may cause mucosal prolapse and reduce exposure, making laparoscopic suturing or stapling more demanding for the surgeon. Although it is commonly accepted that both opioids and volatile anaesthetics induce intestinal paralysis, intestinal hyperactivity during anaesthesia is not uncommon. This randomized trial investigated the effect of different volatile anaesthetics on intestinal motility and the impact on surgeon satisfaction.

Colour solid of CRT phosphors when ambient illumination is present

Abstract Two sets of plots are developed which visualize the CRT colour gamut when ambient illumination is present. the first set of plots represent the solid of CRT colours projected on the 1931 CIE x,y and the 1976 CIE u′, v′ chromaticity plane. It is demonstrated that, earlier, such drawings of the CRT envelope are not correct when the screen is illuminated. The second series of plots visualize the CRT colour solid in full three-dimensional x, y, L space with L the luminance axis. Both sets of pictures may help to perform colour selection and device comparison tasks.

The influence of propofol and sevoflurane on intestinal motility during laparoscopic surgery

Volatile anaesthetics have an influence on small bowel peristalsis during laparoscopic surgery. A recent study concluded that desflurane increased intestinal motility compared to sevoflurane. Hence, a desflurane‐based anaesthesia protocol may reduce surgical exposure during intestinal suturing or stapling due to small bowel hyperperistalsis. The effect of propofol on intestinal motility is not well studied. We tested the hypothesis that a propofol–remifentanil anaesthesia increases intestinal contractions in comparison with a sevoflurane–remifentanil anaesthesia.

Shifts in Perceived Job Content during Early Employment

Abstract This paper focuses on shifts in perceived job content among two occupational panels (office technology workers and machine operators) during the first year of their professional career. A shortened version of Fines Functional Job Analysis is used to measure perceived job content, and at each of the two time stages (i.e. stage T1 and stage T2) the data related to the three domains of People, Things, and Data are optimally scaled and then recoded to a categorical indicator of job content complexity. Shifts in perceived job content are studied by application of log-linear analysis to the multidimensional contingency table obtained by the cross-tabulation of the T1 and the T2 data. The results indicate that there is no general progress or decline in job content activities over time, except for the Things domain. The findings also suggest that there is a substantial symmetry between job progression and degression, and that the bulk of content switches is to adjacent levels of complexity.

Ergonomically Optimal Colours for Colour-Defective CRT Operators

The extension to colour-defective observers of the algorithmic approach (De Corte, 1985a, 1985b, 1985c) for the design of optimal contrasting sets of colours for CRT displays is discussed. The net result is a more practically valuable and a more extensively applicable method. Examples report the computation of optimal colour sets, restricted in saturation, desaturation, and suited either for normal trichromats or colour defective observers. Finally, further developments, which imply a dynamic interplay between computational and experimental results, are considered.

Computation of unique optimal ambients and optimal contrast sets of colours for cathode ray tubes

Abstract An algorithmic scheme named COLSET was recently developed which aims at computing ergonomically optimal colours and ambients for colour CRT work. However, the procedure does not necessarily produce the globally best solution. If only locally optimal estimates were to be obtained, then repeated application of COLSET might result in different guidelines for both colours and ambients. A simulation study, involving several replicated estimations, is reported here to assess this stability or uniqueness issue. The results indicate that with three to five replications there is reasonable certainty that globally best estimates will be found.

Fatigue assessment of a lightweight steel-concrete bridge deck concept

This paper presents results of a constant amplitude fatigue test on a lightweight steel-concrete deck concept, in which a network of longitudinal and transverse concrete ribs transmit shear forces between thin top and bottom steel plates. In order to achieve a lightweight composite structure, the concrete volume is only 32% of the volume between the plates. In previous research the deck was tested statically, indicating that the lightweight steel-concrete sandwich bridge deck concept possesses the necessary static resistance to bridge loads. This paper describes a constant amplitude fatigue test on a full-scale bridge deck test panel (3.60 m × 1.50 m) up to 6 million cycles. During this dynamic test, the deflection of the bridge deck, and steel and concrete strains are recorded on predetermined intervals in order to evaluate the fatigue behavior of the sandwich deck as a function of the number of cycles. The results indicate that the lightweight steel-concrete sandwich bridge deck concept possesses the necessary fatigue resistance to traffic loads.