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Coagulation is the main process for removing natural organic matter (NOM), considered to be the major disinfection by-products (DBPs) precursor in drinking water production. In this work, k-means clusters analysis were used to classify influent waters from two different surface drinking water treatment plants (DWTPs) located in the Mediterranean region. From this, enhanced coagulation models based on response surface methodology (RSM) were then developed to optimise coagulation at two water catchments (river and reservoir). The cluster analysis classified the water quality of the raw waters into two groups related to baseline and peak organic loads. The developed enhanced coagulation models were based on the turbidity, total organic carbon (TOC) and UV254 removals. Sensitivity analysis applied to the models (after predictors selection) determined the factors relative individual contributions for each DWTP scenario. Then, profile plots for enhanced coagulation were studied to identify the optimal levels for each case. Models mean R2 were 0.85 and 0.86 in baseline and 0.85 and 0.84 in peak scenario for river and reservoir catchments, respectively. Results of this study indicate that the surface water quality variation in river DWTP is seasonal and is expressed by an increase of turbidity, while in the reservoir DWTP is related to extreme weather events showing high levels of dissolved organic load (TOC and UV254). During baseline cases, where raw waters present low levels of organics, the three factors optimal adjustment should be ensured to optimise coagulation. Then, during peak scenarios, where influent waters present high organics, the optimal for enhanced coagulation relies on the correct adjustment of Cd. The presented work provides models for drinking water production aimed to propose the optimum conditions for enhanced coagulation, considering the influent water characteristics under different weather conditions.

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The diagnostic usefulness of red cell distribution width (RDW) in association with usual biochemical and haematological parameters in detection of iron deficiency has been studied in a representative sample population of 384 children aged six months to six years in Reunion. Traditional parameters measured included serum ferritin (Fri), total iron binding capacity (TIBC), serum iron (SI), transferrin saturation (TSat), free erythrocyte protoporphyrin (FEP), mean corpuscular haemoglobin concentration (MCHC), mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV) and haemoglobin concentration (Hb). RDW is an index of the variation in red cell size (anisocytosis). This recently derived parameter is measured by some models of electronic cell counter. It is not usually used in epidemiological investigations. Of the children studied, 13.6% had Hb less than 11 g/dl. The Pearson correlation coefficients between circulating iron parameters (SI, TSat, TIBC) or iron storage parameters (Fri) and RDW, MCV, MCH and FEP were greater than with Hb. The best correlations were observed for RDW, MCV and MCH with all other parameters. In this study, the upper limit value of RDW was defined as 18% using a Technicon model H-6000 counter. Other iron deficiency criteria were also defined and found to be in agreement with the international reference values for children aged six months to six years; MCV less than 70 fl, MCH less than 22 pg, MCHC less than 32%, FEP greater than 35 micrograms/dl whole blood, SI less than 6 mumols/l, TIBC greater than 85 mumols/l, TSat less than 10% and Fri less than 12 micrograms/l. The combination of sensitivity and specificity was best for RDW and worst for MCHC.(ABSTRACT TRUNCATED AT 250 WORDS)

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Dietary iron intake has been estimated in 337 healthy, menstruating women, of high social conditions by dietary histories. The mean daily iron intake was 11 +/- 0.13 mg, of which 33% was supplied by meat and fish, whereas fruits and vegetables supplied 29%. The mean daily energy intake was 2,088 +/- 27 kcal (8,723 +/- 113 kJ). In 96.5% of the women, iron intake was lower than the Recommended Dietary Allowances (16-18 mg daily). There was a significantly positive correlation between energy intake and iron intake (r = 0.77; p less than 10(-9]. Therefore, the low iron intake may be considered as a consequence of a decrease in the energy intake observed during the last decades in industrialized countries. Iron fortification of one or several foods seems to be advisable to compensate, at least, partly iron intake deficiency.

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Four groups of rats were fed for 49 d on one of four semi-purified diets, without added cholesterol and containing 230 g/kg of the following isolated proteins: casein, whey, soya-bean or sunflower. Whey, soya-bean and sunflower proteins, when compared with casein, decreased the level of serum high-density-lipoprotein (HDL)-cholesterol. These low cholesterol levels were accompanied by an increase in the daily faecal excretion of neutral sterols and bile acids in the case of soya-bean protein, and by a decrease in the liver cholesterol content, when rats were fed on whey protein. Considering the amino acid composition of the four purified proteins, we observed that serum total and HDL-cholesterol levels had a significant positive correlation with tyrosine and glutamic acid, and a negative correlation with cystine and alanine. The present study showed that the hypocholesterolaemic effect of dietary proteins was not related to their animal or vegetable origin.

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Milk intake of mouse pups was controlled by adjusting litter size at birth to four, nine or 20 pups. Litters of nine were considered as control groups. In adult animals many differences were seen among the three groups which had received the same diet ad libitum after weaning. Differences in body lipids largely accounted for the differences in body weight in both males and females. In parametrial adipose tissue, adipose cells, compared to those of controls, were enlarged and more numerous in mice from small litters, and smaller and less numerous in mice from large litters. After an overnight fast, the insulin response to glucose loading was highest in the obese group of mice, while it was absent in the lean group, suggesting permanent impairment in the secretion of insulin. Liver slices from animals which were bred in small litters incorporated more [U14C]-glucose into triglyceride moieties and cholesterol esters. Some of the metabolic changes in adipose tissue were related to cell size. With increasing litter size, glucose was incorporated into glycogen in muscle to a greater extent. Thus early feeding patterns induced permanent morphological, metabolic and hormonal changes in adults. Animals overfed in early life became obese and underfed animals remained lean when adults.

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Lean mice were made obese by feeding, ad libitum, a high-lard diet. They showed an increased fat cell size and number which were maintained when this diet was replaced by the control high-carbohydrate diet for 10 weeks. Obese fed mice showed normal glucose and insulin serum levels, but insulinaemia was elevated after an overnight fast. The insulinaemic response after intraperitoneal injection of glucose was insignificant. Thus hyperinsulinism is not a prerequisite for the development of obesity. High-fat diet influenced, in vitro, glucose metabolism of adipose tissue, liver and muscle: basal lipogenesis was markedly reduced in adipose tissue and liver, and glucose oxidation was decreased in muscle. Insulin sensitivity was reduced by increased fat cell size. De novo formation of fatty acids in liver and adipose tissue did not contribute to the development of obesity. The increased lipoprotein lipase activity of the large fat cells suggested that obesity resulted from a direct storage of dietary fatty acids esterified by glycerol formed from circulating glucose.

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