Quality of decision making and group norms.

Two studies investigated the impact of group norms for maintaining consensus versus norms for critical thought on group decisions in a modification of the biased sampling paradigm (G. Stasser & W. Titus, 1985). Both studies showed that critical norms improved the quality of decisions, whereas consensus norms did not. This effect appeared to be mediated by the perceived value of shared and unshared information: Consensus norm groups valued shared information more highly than critical groups did, and valence was a good predictor of decision outcome. In addition, the 2nd study showed that the group norm manipulation has no impact on individual decisions, consistent with the assumption that this is a group effect. Results suggest that the content of group norms is an important factor influencing the quality of group decision-making processes and that the content of group norms may be related to the group's proneness for groupthink.

Social processes and group decision making: anonymity in group decision support systems.

Various social processes in decision-making groups are considered detrimental to the quality of decisions. It is often assumed that removing the ability for groups to exert strong social influence on its members improves group decisions. Group Decision Support Systems (GDSSs) are increasingly used to remedy the social faults of the decision-making process in groups. In these systems, anonymity is seen as a tool to reduce the impact of the group over its members, and therefore as the key to improved group performance. This meta-analytic review examines the assumption that anonymity in GDSSs is beneficial for group decision-making on a range of performance indicators. In 6 meta-analyses of 12 independent investigations there is no support for this hypothesis. The only reliable effect of anonymity was to lead to more contributions, especially more critical ones. An alternative model is presented to account for the findings. This model argues that performance in decision-making groups depends on the social context and relevant social norms as well as on system characteristics such as anonymity. It is concluded that the integration of anonymity into phases of group decision support does not guarantee improved performance.

The sterilization of honey with cobalt 60 gamma radiation: a study of honey spiked with spores of Clostridium botulinum and Bacillus subtilis.

Unprocessed honey is a recognized wound-healing remedy. However, to make clinical use of honey acceptable, it should be sterile. To find the lowest dose of irradiation needed for sterilization, six batches of honey (a-f) were gamma irradiated with 6, 12, 18, 22 and 25 kGy Cobalt-60. After a dose of 25 kGy the antibacterial activity was not altered. Presumably glucose oxidase (EC 1.1.3.4), which produces hydrogen peroxide, is not easily damaged by irradiation. Amylase activity on the other hand was significantly reduced to 19%, 19%, 21%, 22%, 43% in batches a), b), c), d) and f) respectively, whereas no decrease was observed in batch e). All batches spiked with approximately 10(6) spores from Cl. botulinum or B. subtilis per 50 g honey proved to be sterile after irradiation with a dose of 25 kGy. Honey was also spiked with Cl. botulinum at up to 5000 spores per 50 g honey, which is the upper limit of natural contamination. The sterilizing dose in this case was 18 kGy.

Absence of guar efficacy in complex spaghetti meals on postprandial glucose and C-peptide levels in healthy control and non-insulin-dependent diabetes mellitus subjects.

The effects of guar incorporated into a complex spaghetti meal on the glycaemic response in 11 healthy and 6 non-insulin dependent diabetic (NIDDM) subjects was studied. To this end, subjects consumed spaghetti made of either Triticum aestivum or Triticum durum wheat with or without 20 g% guar, as part of a complex meal containing 27% fat, 19% protein and 51% carbohydrate. In both the healthy as well as the NIDDM subjects the incremental integrated postprandial glucose and C-peptide responses after ingestion of a guar spaghetti meal were not different from the values found after a spaghetti meal without guar. In NIDDM subjects the incremental glucose and C-peptide levels were lower at 60 and 90 min and 90 and 150 min respectively after ingestion of guar aestivum spaghetti. Our negative results of effects of guar on postprandial glucose values may be explained by the presence of normal quantities of fat and protein in the meal and imply that addition of dietary fibre to a complex meal is not useful in the dietary management of NIDDM.

Dietary fibre in the management of diabetes mellitus: a review.

The role of nutritional habits in the emergence of certain diseases in the western world enhanced the interest in nutrition. As a consequence, the importance of what is now called dietary fibre has changed from an unnecessary constituent of plant food to an essential element of healthy nutrition. Several diabetes associations now advise including a defined amount of dietary fibre in an up-to-date dietary treatment of diabetes mellitus. However, there are still many controversies and unanswered questions. This paper reviews briefly the problems of definition and determination of dietary fibre. The possible mechanisms of action are discussed, and a survey of data in the literature that deal with the effect of long-term ingestion of increased amounts of dietary fibre on carbohydrate and lipid metabolism, safety and applicability is presented.

The influence of guar-gum bread on the regulation of diabetes mellitus type II in elderly patients.

The effect of a high-fibre bread mixed with guar-gum (75 g/kg flour) on serum glucose, connecting peptide (C-peptide), haemoglobin A1 (HbA1), high-density-lipoprotein-cholesterol (HDL-cholesterol) and triglycerides was examined in fourteen elderly patients with diabetes mellitus type II. The mean daily consumption of guar gum was 8.1 g. Gastrointestinal disorders were not observed. Consumption of guar-gum bread resulted in a significant decrease in C-peptide values on the 1st day and blood glucose values after 3 weeks (both measured 90 min after breakfast). C-peptide values remained low, while an unaccountable 'rebound' phenomenon was seen in the blood glucose values 90 min after breakfast at the end of the study. No significant change was seen in respect to HDL-cholesterol and triglycerides. However, a small significant increase in HbA1 was noted.