EFFECT OF STORAGE ON THE RHEOLOGICAL BEHAVIOUR OF BABY FOODS

The effect of storage temperature on rheological behaviour of four varieties of baby foods was studied. After 24-month storage at 15C and 25C, the constant A in Weltman model increased significantly for the vegetables, meat and fish samples, and decreased significantly for the fruit samples. After 24-month storage at 5C and 15C there were no significant changes in flow behavior index, consistency index and yield stress of the Herschel-Bulkley model for the vegetables, meat, fish and fruit samples. Increase in storage temperature decreased the consistency index and yield stress of the fruit samples.     

NMR IMAGING, CALORIMETRIC, and MATHEMATICAL MODELING STUDIES of FOOD FREEZING

Nuclear magnetic resonance imaging (MRI), calorimetry, and temperature measurements were used to monitor cylindrical potato sections frozen at -11C and -42C. MRI showed the advance of the nonsymmetric freezing zone and loss of signal intensity as liquid water turned to ice. Differential calorimetry was used to follow heat removal during transient freezing. Measured times to 95% enthalpy change were 24 min (-42C) and 49 min (-11C), as compared to modeled values of 29 min (-42C) and 100 min (-11C). Times to 95% change in the NMR signal, integrated over the area of the image, were 21 min (-42C) and 56 min (-11C). Changes in NMR signal intensity could be correlated with the amount of unfrozen water remaining after a steady-state had been reached. At -42C, NMR indicated 25% unfrozen water remaining as compared to 26% by calorimetry, and 22% by modeling. At -11C, NMR measured 67% unfrozen water remaining as compared to 48% by calorimetry, and 25% by equilibrium modeling.     

Kinetic model for water/oil absorption of mesquite gum (Prosopis juliflora) and gum arabic (Acacia senegal)

The water and oil uptake of mesquite and arabic gums in powdered form was studied at temperatures of 23, 35 and 45°C. A previously proposed equation to predict osmotic equilibrium was tested using the experimental data with both gums and a good statistical fit was obtained. Mesquite gum showed the highest water and oil absorption at all temperatures studied. Temperature dependence of the reciprocal of the S₁ and WL_∞ were determined using an Arrhenius equation. The activation energy for water and oil absorption for gum arabic was 21.98 and 39.57 kJ mol⁻¹, compared to that of mesquite gum having values of 15.79 and 46.16 kJ mol⁻¹, respectively. A second order kinetic model was obtained for water and oil absorption for both gums.     

Accuracy of patient recall of opportunistic smoking cessation advice in general practice

OBJECTIVE: To determine the accuracy of patient recall of a question about smoking in a specified consultation in general practice; the accuracy of smokers' recall of advice to stop smoking; and predictors of accurate recall. DESIGN: Analysis of 1075 audiotapes was compared blind with matching patient questionnaires administered after the consultation to calculate sensitivity and specificity for patient recall as a dichotomous variable. Predictors of recall were determined by logistic regression. SETTING: General practitioner training practices, New South Wales, Australia. SUBJECTS: Thirty-four trainees and consecutive samples of their patients 16-65 years of age. RESULTS: Patient recall of a question about smoking had a high false positive rate of 21% but a sensitivity of 93%. Smokers over-reported advice to stop smoking (specificity 82%; sensitivity 92%). Predictors of accuracy of a question about smoking included patient sex (women 1.58 times more likely than men to be accurate); smoking status (smokers 1.7 times as likely as non-smokers to be accurate); and interval since consultation (those who completed their questionnaires within a week were 1.84 times more likely to be accurate). CONCLUSIONS: Patient recall is systematically biased towards over-reporting of a question about smoking status and, among smokers, of advice to quit. Although we recommend its continued application in health services evaluation, findings should be interpreted with caution, particularly if subjects are male or the interval between recall of smoking cessation advice and the occasion of service in which it might have occurred is considerably delayed.


     

Detecting delaminations in a composite beam using anti-optimization

The present study proposes a detection technique for delaminations in a laminated beam. The proposed technique optimizes the spatial distribution of harmonic excitation so as to magnify the difference in response between the delaminated and intact beam. The technique is evaluated by numerical simulation of two-layered aluminum beams. Effects of measurement and geometric noise are included in the analysis. A finite element model for a delaminated composite, based on a layer-wise laminated plate theory is used in conjunction with a step function to simulate delaminations     

An anthropocentric approach to knowledge-based preventive maintenance

It is common knowledge today that application of sound manufacturing concepts and techniques will only provide cost-effective, long-term return when manufacturing functions are totally integrated with the operators, maintenance engineers and other associated personnel. This paper presents a human-centred methodology and its associated knowledge-based tool, to utilize equipment failure information for the purpose of machine down-time minimization. Based upon a structured and rigorous assessment of each breakdown, and combined with total employee participation, continuous improvement of maintenance function and operational effectiveness of equipment can be made a reality.     

Fertilization in vitro. A review over the medical indications and suggestion to unified guidelines for public fertility clinics in Denmark

Medical indications for in vitro fertilization and embryo transfer (IVF-ET) internationally and in Denmark are reviewed. Reports from large international centres document that tubal infertility, unexplained infertility, endometriosis and male infertility are equally good indications for IVF. Traditionally, tubal infertility has been the only medical indication qualifying for IVF treatment within the National Health Service in Denmark. Thus, in this country, couples with unexplained and male infertility and with endometriosis have to pay up to 25,000 D.Kr. per IVF-ET treatment in private fertility clinics. Since there is no scientific basis for this discrimination, it is urged that the present rules are changed, so that couples with unexplained and male infertility and endometriosis are also allowed IVF treatment free of charge in the public fertility clinics.     

Expression of a human homeobox-containing gene is regulated by 1,25(OH)2D3 in bone cells

The seasonal variation in the nutrient composition of Enhydra fluctuans and Marsilea quadrifolia, two edible semi-aquatic plants, was studied in order to promote their consumption as green leafy vegetables. Both plants had a high crude protein content throughout all harvesting seasons. Enhydra fluctuans had a low ash content and was a good source of beta-carotene (3.7 to 4.2 mg/100 g on a fresh weight basis). Marsilea quadrifolia exhibited wide fluctuations between seasons and was not very promising in nutrient composition when compared to other commonly used green leafy vegetables.