No description available.

Yes / This paper makes use of a leading UK supermarket’s loyalty card based data which records information on purchase decisions by consumers who shop at its stores in order to assess the effectiveness and impact of the UK reduced salt campaign. We present an empirical analysis of consumption data to assess the effectiveness of the UK Food Standard Agency’s (FSA) ‘reduced salt campaign’ on the basis of information on health related announcements undertaken by the FSA under its ‘low salt campaign’. We adopt a general approach to determining structural breaks in consumption data, including making use of minimum LM unit root tests whereby structural breaks are endogenously determined from the data. We find evidence supporting the effectiveness of the FSA’s reduced salt campaign.

Abdulrahman Al-Humiany (1999) A Comparison of the Responses to Enviromental Stress of the Gram-Positive Bacterium Staphylococcus xylosus and the Gram-Negative Bacterium Halomonas Halo. PhD Thesis, Department of Molecular Biology and Biotechnology, University of Sheffield. Salt tolerance of the Gram-negative bacterium, Halomonas Halo, was compared with the salt tolerance of a newly isolated Gram-positive coccus Staphylococcus xylosus. Both organisms grew over a range of salinities from 0.1 - 3.0 M NaCI in both rich medium containing yeast extract and in minimal medium. In the absence of yeast extract, growth of S. xylosus was very slow at 3.0 M NaCl and its optimum salinity for growth was 0.1 M NaCl, whereas Halomonas Halo showed optimum growth at 0.5 M NaCl. Growth experiments replacing NaCI with KC1 and the effect of Na+ on the rate of respiration showed that Halomonas Halo had a greater requirement for Na+ for growth than S. xylosus. When betaine was added to the minimal medium, it greatly increased the growth rate of both organisms at 3M NaCl. The precursor of betaine, choline, was also effective in increasing the growth rate of Halomonas Halo, but was much less effective for S. xylosus. Both organisms transported betaine into the cells by an energy dependent transport system; transport rates were broadly similar, but it appeared that the halotolerant S. xylosus took up betaine more efficiently than Halomonas Halo. Halomonas Halo and S. xylosus were shown to grow across a pH range from 5.5 - 8.5, but S. xylosus showed optimum growth across the full range whereas Halomonas Halo showed a distinct optimum at pH 7.0. The proton motive force (Ap) was found to be low in both organisms and at pH 8.5, it fell below the theoretical minimum (150 mV) which is required for ATP synthesis. Ap was significantly reduced by the inhibitor carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and to a much lesser extent by monensin. Both inhibitors completely stopped the growth of both organisms at pH 7.0. The possibility that compatible solutes may protect enzymes from thermal denaturation was examined, but the results were inconclusive.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

published_or_final_version / Chemistry / Master / Master of Science

Salt can be removed by viscous flow and dissolution to form a salt weld. A complete weld forms when salt is completely removed by these processes. Where salt removal is incomplete, a partial weld forms. Though welds are frequently mentioned in the literature, the details of weld formation and the properties of salt welds are poorly understood. In Chapter 1, I use analytical and numerical models to quantify the role of viscous flow during salt welding. Where salt flow is limited by boundary drag against the salt contacts, evacuation is slow and up to ~50 m of salt will be left behind in a partial weld. Where salt flow is laterally unrestricted, a vanishingly thin (<< 1 m) smear of salt will remain. I conclude that layer-parallel wall rock translation or dissolution must act to remove any remnant salt to create a complete weld. In Chapter 2, I characterize partial welds containing halite and anhydrite on reflection seismic data by treating welds as thin beds. Below the temporal resolution of reflection seismic data, typically ~25-50 m for modern surveys with peak frequencies of ~10-30 Hz, reflections from the upper and lower evaporite contacts converge and interfere to form a single composite reflection. Thus, partial and complete welds are typically indistinguishable using travel-time differences alone. I then use amplitude information from synthetics and seismic examples to estimate remnant evaporite thickness. In Chapter 3, I investigate fluid flow near and through salt welds. I conclude dissolution during boundary flow can remove up to a few meters of salt per million years. Though dissolution plays a volumetrically insignificant but important role in weld formation, as runaway dissolution can create pathways for focused cross-weld migration of subsurface fluids. I identify features that influence cross-weld migration of subsurface fluids and then develop an empirical relationship between weld geometry and the tendency seal or leak hydrocarbons. I find that in the Campos Basin, offshore Brazil, salt welds containing remnant evaporites thinner than ~50 m that are broader than ~25 km2 in area are likely to leak. / text

The purpose of this study was to assess the amount of sodium in the diet of normal adults. The population consisted of 86 adults, 49 females and 37 males, who were participants in the Family Heart Study (FHS). Of this population 26 were studied during the baseline assessment period and were just entering the program. The remaining 60 people were studied after participating in the FHS for one year. Three methods were used to assess sodium intake: a salt questionnaire, a salt preference test and the sodium content of a 24-hour urine collection. The salt questionnaire consisted of questions to assess the frequency of intake of high sodium foods and the use of salt at the table and in cooking. The salt preference test was done using a baked potato salted to taste by the participants. The salt questionnaire and salt preference test were compared to the amount of sodium in a 24-hour urine collection. There was no relationship among any of these measures of salt intake. The urinary analysis for sodium indicated that the participants in this study had a moderately high sodium intake (143 mEq/day), similar to other studies in the U.S. Males excreted more sodium than females. The group assessed at baseline and the group assessed after one year in the study both excreted the same amount of sodium. The year one group had switched to Lite salt and reduced their use of salt during cooking; however, they used salty foods with the same frequency as the baseline group. The urinalysis demonstrates that the changes made by the year one group were not significant in reducing their salt intake. The amount of sodium excreted showed no relationship to blood pressure. This finding is similar to other studies in the U.S. because most people consume over 70 mEq sodium/day, which is above the proposed threshold to prevent hypertension. The genetic variability in the U.S. population obscures any relationship of sodium intake to blood pressure. Some of the major problems in assessing sodium intake are the variability from day to day and the ubiquity of sodium in our foods. It was concluded that urinary assessment of sodium was the best method available at this time, although multiple collections are necessary to compensate for the variability of sodium intake. / Graduation date: 1981

The effect of reducing sodium chloride in Cheddar cheese was studied. Milled curd from a split-lot was salted at selected NaCl concentrations and analyzed through aging by sensory and rheological tests. Estimation of differences in compositional analysis, lactic acid populations, degree of proteolysis, water activity, and pH were also determined. Consumer panel analysis of the cheese on a hedonic scale over seven months aging showed no significant differences in overall desirability between cheese containing 1.75 - 0.88% NaCl. At 0.75% NaCl in cheese, ratings were lower, but flavor and texture scores were considered acceptable. Addition of even a small amount of salt (0.38 - 0.44%) significantly improved sensory characteristics relative to an unsalted cheese. Regression analysis of trained panel evaluations to predict consumer response showed that "firmness" and "adhesiveness" were the most important attributes for favorable consumer ratings of texture. Trained panel determination of "Cheddar intensity" and "unpleasant aftertaste" were found to be the two most important factors for determining consumer panel flavor scores. These four attributes, as rated by the trained panel, correlated with salt concentration in cheese. Instron evaluation of reduced sodium Cheddar cheese showed a decrease in firmness, chewiness, and gumminess and an increase in determinations showed an increase in proteolysis and water activity and a decrease in pH of the finished cheese. Lactic acid bacterial populations were significantly higher in the cheese containing reduced NaCl concentrations with the highest population differences observed through one month of age. / Graduation date: 1984

No description available.

No description available.