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Abstract: In this research, we measure the iron bioavailability of micronized ferric orthophosphate when it is used to fortify low-fat fluid milk enriched with calcium and petit suisse cheese using the prophylactic-preventive method in rats. Four groups of male weaned rats received a basal diet (control diet; 6.5 ppm Fe), a reference standard diet (SO4Fe; 18.2 ppm Fe), a basal diet using iron-fortified fluid milk as the iron source (milk diet; Fe ppm 17.9), and a basal diet using iron-fortified petit suisse cheese as the iron source (cheese diet; 18.0 ppm Fe) for 22 d. The iron bioavailability of the different sources was calculated as the ratio between the mass of iron incorporated into hemoglobin during the experiment and the total iron intake per animal. The relative biological values with regard to the reference standard (RBV%) were 61% and 69% for the milk and cheese diet, respectively. These results show that according to this method, the iron bioavailability in both fortified foods can be considered as medium bioavailability rates.

Although previous functional brain imaging studies have found that the insula responds selectively to facial expressions of disgust, it remains unclear whether the insula responds selectively to disgust-inducing pictures. In this fMRI study, healthy volunteers viewed pictures of contamination, human mutilation, attacks and neutral scenes during scanning, and then rated pictures for the ‘basic’ emotions. The anterior insula responded to contamination and mutilation but not attacks, while the ventral visual areas responded to attacks and mutilations more strongly than contamination. The above activations were predicted by disgust and arousal ratings respectively. Additionally, mutilations uniquely activated the right superior parietal cortex. These results support selective disgust processing at the insula, and suggest distinct neural responses to contamination and mutilation.

The study employed the signal-detection paradigm as a model for investigating age related biological vs cognitive (decision) effects on perceptual behavior. Old and young subjects reported the presence or absence of sugar in threshold level solutions and tap water. It was found that the aged subjects displayed a higher detection threshold. They also obtained a higher (stricter) criterion of decision, fewer false-positives and a greater false-negatives-to-total-errors ratio. These findings were interpreted as strategic behavior motivated by the elderly subjects' greater need to perform well through reducing the error rate.A post-hocinterview found that most subjects equated the term 'error' with false-positives only. Therefore, the negative response bias found among the elderly subjects may represent a strategic attempt to reduce the rate of false-positive errors. It is also speculated that it may reflect a need to save energy, since negative responses imply an unwillingness to commit oneself to exert effort.

This study intended to explore age-related strategies of information seeking and decision making, utilizing a content-free task. Better understanding of skills and motives of aged behavior might contribute to more effective intervention for their welfare. Young and old female participants were engaged in detecting the presence of sucrose in solutions of various concentrations. They also reported the number of samplings required for an affirmative or negative decision about each test solution. Compared to young people, the aged sampled more (repetitions) and had a higher detection threshold (intensity of stimulus), indicating higher requirements for information. It was assumed that the sampling curve would be bell-shaped and peak at the point of least certainty about the presence or absence of sucrose (probability of detection = 0.5). Such curve was observed only among the young females when the samplings across concentrations were pooled according to probability of detection. In the aged, the sampling curve was rather monotonic, indicating low utility and interchangeability of information resources. This was attributed to a preset sampling strategy, labeled as over-resourcing, considering the higher baseline and low utility. The implications of such strategy to experimental procedures and every day life were discussed.