A Combined Field And Laboratory Investigation Into The Transport Of Fecal Indicator Microorganisms Through A Shallow Drinking Water Aquifer In Bangladesh

This dissertation presents an examination of the causes and mechanisms underlying the widespread contamination of a shallow groundwater aquifer by fecal bacteria. The context for this study is a field site located in a rural area of Bangladesh that represents a microcosm for the many challenges facing the approximately 2 billion people worldwide who rely upon groundwater for their daily needs. The unique contributions of this work include an improved numerical model for fitting column test results, a conceptual model to explain seasonal patterns of well contamination based on the hydraulic interaction of ponds and irrigation/drainage canals and a new understanding of the important role that such canals might play in predicting the microbial contamination of shallow aquifers in flood-protected areas. The mechanisms responsible for filtration of the fecal indicator bacteria, Escherichia coli, during passage through the fine sand aquifer were first investigated through laboratory column experiments using intact sediment cores from the field site as well as repacked sediment that had been dried and, in some experiments, chemically cleaned. To fit the hyper-exponential spatial profiles of attached bacteria in one third of the experiments, a finite difference two-population model with reversible and irreversible attachment modes incorporating bacterial die-off was developed. Where the two-population phenomenon was observed, one population typically was highly irreversible while the other was reversible with a smaller irreversible attachment rate. When applied to transport in the field, this model predicted only a two-fold reduction in bacterial concentrations over a distance of 10 m and transport was limited mainly by the bacterial die-off rate, which was also measured using microcosm experiments. The occurrence of the second population was associated with larger grain size and lower percentage of fine particles and the attachment rates in general increased linearly with increasing percentage of fines. Transport from contaminated surface water to nearby tubewells was studied in the field through measurements of bacterial infiltration below canals and ponds both inside and outside of the flood control embankment. A two-dimensional finite element model of the field-pond-canal system was built and fitted to heads measured at three monitoring wells and 2 surface water bodies. Using parameters from the field measurements, the model was not able to explain the seasonal pattern of E. coli concentrations in tubewells, even when reversible attachment assumptions from the column test results were applied. An alternative conceptual model that incorporates the seasonal shift in flow direction caused by the canal network was developed using the fitted finite element model and could explain the observed pattern of well contamination. The importance of the irrigation/drainage canals in determining the frequency of tubewell contamination by E. coli at the site was further demonstrated by applying a logistic regression model using the intensity of latrines, canals and ponds as predictors, after applying spatial decay rates drawn from the infiltration literature. The resulting Intensity Model found that population density, unsanitary latrines and canals together could explain 48% of the variation in the frequency of E. coli detection in tubewells, but these parameters were only significant at a low spatial decay rate (0.01 m-1). A less complex Proximity Model provides nearly the same explanatory power but only required population with 25 m and the distance to the nearest canal as predictors. These models could be useful in predicting water-related health risks, evaluating contamination risk for groundwater sources based on the sanitary environment around the well or estimating the potential benefits from improvements to sanitation infrastructure in a given region

How do minimum cigarette price laws affect cigarette prices at the retail level?

Objectives: Half of US states have minimum cigarette price laws that were originally passed to protect small independent retailers from unfair price competition with larger retailers. These laws prohibit cigarettes from being sold below a minimum price that is set by a formula. Many of these laws allow cigarette company promotional incentives offered to retailers, such as buydowns and master-type programmes, to be calculated into the formula. Allowing this provision has the potential to lower the allowable minimum price. This study assesses whether stores in states with minimum price laws have higher cigarette prices and lower rates of retailer participation in cigarette company promotional incentive programmes

Cigarette advertising and promotional strategies in retail outlets: results of a statewide survey in California

OBJECTIVE—To examine the extent and types of cigarette advertising materials in stores and to assess tobacco company compliance with the 1998 Master Settlement Agreement (MSA).DESIGN—A cross-sectional analysis of a random sample of 586 stores that sold cigarettes.SETTING— US state of California.MAIN OUTCOME MEASURES—Trained data collectors classified cigarette advertising materials by type (signs, displays, functional items), location (interior or exterior), and placement (below 3 feet (1 m) or near candy).RESULTS—California retail outlets featured 17.2 (SD 16.1) tobacco advertising materials on average, and 94% of stores featured at least some advertising. About 85% of these were within 4 feet (1.3 m) of the counter. About 50% of the stores had ads at or below 3 feet, and 23% had cigarette product displays next to candy. In violation of the MSA, 3% of stores featured signs with cartoons and 11% had large exterior signs.CONCLUSIONS—Tobacco companies are aggressively using stores to market cigarettes. Moreover, the spirit of the MSA—to protect children from cigarette advertising—has not been realised. Future studies should monitor industry use of this venue and assess the impact of exposure to cigarette advertising materials in stores on adult smokers and youth.Keywords: advertising; point-of-sale advertising; tobacco industr

How tobacco companies ensure prime placement of their advertising and products in stores: interviews with retailers about tobacco company incentive programmes

Background: About 81% of cigarette manufacturers' marketing expenditures in the USA is spent to promote cigarette sales in stores. Relatively little is known about how these expenditures help the manufacturers achieve their marketing goals in stores. A better understanding of how tobacco companies influence the retail environment would help researchers and tobacco control activists to monitor industry presence in stores

Evolving water point mapping to strategic decision making in rural Malawi

There is a need to evolve from the simple mapping of water points, now often numerous, to effective decision making using these data. This paper outlines new developments of mWater as the preferred online Management Information System (MIS) tool to analyse significant volumes of water and sanitation data in Malawi. mWater exemplifies an evolving strategic decision-making tool used to formulate rural water supply investment strategies. A time series of 25,000 water points have been mapped since 2011 to build a complete asset register of water infrastructure to support government endeavours to reach Sustainable Development Goal 6. This comprehensive live database allows real-time analysis of over sixty variables, including linkage to concurrent mWater sanitation and waste data. This paper briefly illustrates several emergent uses of the facility to exemplify its potential in strategic decision making using Big Data. It is currently being rolled out across the entire country

Status of the PICASSO Project

The Picasso project is a dark matter search experiment based on the superheated droplet technique. Preliminary runs performed at the Picasso Lab in Montreal have showed the suitability of this detection technique to the search for weakly interacting cold dark matter particles. In July 2002, a new phase of the project started. A batch of six 1-liter detectors with an active mass of approximately 40g was installed in a gallery of the SNO observatory in Sudbury, Ontario, Canada at a depth of 6,800 feet (2,070m). We give a status report on the new experimental setup, data analysis, and preliminary limits on spin-dependent neutralino interaction cross section.Comment: 3 pages, 2 figures. To appear in the Proceedings of the TAUP 2003 conference, 5-9 September, 2003, University of Washington, Seattle, US

Recent Progress and Recommendations on Celiac Disease From the Working Group on Prolamin Analysis and Toxicity

Celiac disease (CD) affects a growing number of individuals worldwide. To elucidate the causes for this increase, future multidisciplinary collaboration is key to understanding the interactions between immunoreactive components in gluten-containing cereals and the human gastrointestinal tract and immune system and to devise strategies for CD prevention and treatment beyond the gluten-free diet. During the last meetings, the Working Group on Prolamin Analysis and Toxicity (Prolamin Working Group, PWG) discussed recent progress in the field together with key stakeholders from celiac disease societies, academia, industry and regulatory bodies. Based on the current state of knowledge, this perspective from the PWG members provides recommendations regarding clinical, analytical and legal aspects of CD. The selected key topics that require future multidisciplinary collaborative efforts in the clinical field are to collect robust data on the increasing prevalence of CD, to evaluate what is special about gluten-specific T cells, to study their kinetics and transcriptomics and to put some attention to the identification of the environmental agents that facilitate the breaking of tolerance to gluten. In the field of gluten analysis, the key topics are the precise assessment of gluten immunoreactive components in wheat, rye and barley to understand how these are affected by genetic and environmental factors, the comparison of different methods for compliance monitoring of gluten-free products and the development of improved reference materials for gluten analysis

Statement of the Prolamin Working Group on the Determination of Gluten in Fermented Foods Containing Partially Hydrolyzed Gluten

On August 12, 2020, the U.S. Food and Drug Administration (FDA) has finalized a rule related to gluten-free labeling for foods containing fermented, hydrolyzed ingredients. The FDA believes that there is no scientifically valid analytical method e ective for determining gluten in fermented or hydrolyzed foods. In the absence of an analytical method, the FDA has decided to evaluate gluten-free claims on these foods based only on evidence that the food or ingredient used is gluten-free before fermentation or hydrolysis. For example, barley-based beers from which gluten is removed during brewing using special filtration, adsorption and/or enzymatic treatment are therefore excluded from bearing a gluten-free label. The Prolamin Working Group (PWG) acknowledges that the FDA rule is a regulatory act and might have to take into consideration several aspects other than scientific evidence, including risk assessment. Nevertheless, the PWG thinks that science has to be the most important driver for regulatory acts in risk management.Fil: Scherf, Katharina Anne. Karlsruher Institut Für Technologie; AlemaniaFil: Catassi, Carlo. Università Politecnica Delle Marche; ItaliaFil: Chirdo, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Ciclitira, Paul J.. University of East Anglia; Reino UnidoFil: Feighery, Conleth Francis. Universidad de Dublin; IrlandaFil: Gianfrani, Carmen. Institute of Biochemistry and Cell Biology; ItaliaFil: Koning, Frits. Leiden University; Países BajosFil: Lundin, Knut E. A.. University of Oslo; NoruegaFil: Masci, Stefania. No especifíca;Fil: Schuppan, Detlef. No especifíca;Fil: Smulders, Marinus J. M.. Wageningen University and Research; Países BajosFil: Tranquet, Olivier. No especifíca;Fil: Troncone, Riccardo. University Federico II; ItaliaFil: Koehler, Peter. No especifíca