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Regarding neonates and infants, the videofluoroscopy swallowing study is always conducted with liquids impregnated with a radiopaque material in varied proportions and thickenings. Variations in thickening and barium concentration are known to change the swallowing function. The present study aimed to analyze the rheological and macroscopic properties of barium contrast and liquids commonly used in Brazil with infants under six months old. This study was approved by the Ethics Committee under certificate number 63361616.2.0000.5482. Rheological measurements were performed on samples of breast milk and infant formulas, pure, with thickener, impregnated with liquid barium sulfate, as well as a pure barium sulfate sample. The data collected showed similar viscosity rates between breast milk and the infant formulas Aptamil and Enfamil. Impregnating them with 20% and 33% liquid barium sulfate increased their viscosity. However, they remained in the same classification, despite the quantitative differences in their apparent viscosity. The regular products, in formulation with thickener and thickener plus 20% barium, showed an increase in apparent viscosity close or twice to that of Enfamil A.R. impregnated with 33% barium sulfate. The study allowed a more in-depth understanding of how the products behave at strain rates consistent with the conditions when swallowing. The results indicated in this study confirm the need for knowledge and care in preparing liquids to be offered in videofluoroscopy swallowing studies with neonates and infants. They also emphasize the importance of objectively measuring the viscosities of videofluoroscopic fluids, matching them with the liquids to be prescribed in their diets. [ABSTRACT FROM AUTHOR]

The videofluoroscopy swallowing study is considered a gold standard for the precise diagnosis in feeding/swallowing disorders. Regarding neonates and infants, the evaluation is conducted exclusively with barium sulfate‐impregnated liquids. This exploratory study aimed at analyzing the rheological and macroscopic properties of liquids usually presented during videofluoroscopy swallowing studies in Brazil, considering that products often differ from one country to another. Rheological measurements were taken of one sample of infant formula, one of the breast milk, and another two of these liquids impregnated with barium sulfate. Considering the value of 50 s‐1, average shear rate, the addition of barium sulfate made breast milk 18 times more viscous, and Aptamil 18.5 times more viscous, reaching thresholds close to that of mildly thick. The use of liquids in viscosity as close as possible to what will be proposed in the patient's diet indication is crucial for their safety. Practical applications: This exploratory study highlighted the importance of the knowledge of the macroscopic properties of liquids usually presented during videofluoroscopy swallowing studies. Knowing the flow behavior obtained through rheological studies of untreated breast milk and infant formula, both alone and impregnated with barium sulfate, it provides quantitative information from specific products of routine use in Brazil that can assist speech‐language‐hearing therapists and radiologists cope with the challenging issue of making examination conditions as close as possible to the infant's feeding routine. Such information can contribute to more accurate results which will ensure better treatment indications. [ABSTRACT FROM AUTHOR]

The injection of seawater into oil-bearing reservoirs to maintain reservoir pressure and improve secondary recovery is a well-established, mature operation. Moreover, the degree of risk posed by deposition of mineral scales to the injection and production wells during such operations has been much studied. The current deepwater subsea developments offshore West Africa and Brazil have brought into focus the need to manage scale in an effective way. To this end, the challenge of scale control during the lifecycle of water injection, production, and produced-water reinjection (PWRI) has been reviewed for a number of fields by the authors. This paper outlines the risk assessment process that should be undertaken to select the most economical and effective scale control methodology (which for sulfate-based scale could be seawater injection with scale inhibitor squeeze treatments to maintain production, or sulfate reduction of the injection water with or without the need to scale inhibitor squeeze). In the case of sulfate reduction, parameters to be. investigated include the degree of desulfation required to minimize the scale risk of downhole scale formation, the impact the degree of fluid mixing will have on the resulting brine (from injection to production), and the impact the desulfated brine will have on scale control during PWRI. The paper draws on a wide range of technical inputs to make scale management decisions including: computer modeling techniques (e.g., deposition models that incorporate the kinetics of sulfate scale formation at low supersaturation ratios), reservoir simulation of fluid mixing and reaction; the resulting produced brine chemistry, laboratory-generated coreflood data to assess chemical selection for scale inhibitor squeeze and produced water application; and field results that will demonstrate the impact of the type of injection water source on the long-term manageability of such deepwater projects. Finally, the paper outlines in detail the particular issues associated with the full economic assessment of low-sulfate water injection vs. full sulfate seawater injection. [ABSTRACT FROM AUTHOR]

This paper describes field experience and lessons learned from scale control operations in a deepwater subsea development in the Campos Basin, Brazil; specifically, from bullheading scale inhibitor squeezes from the FPSO host, along the production flowlines, into four low-watercut, horizontal subsea wells, completed with sand control. The relatively small number of high-cost, highly productive wells, coupled with a very high barium-sulfate scaling tendency upon breakthrough of injection water, meant that not only was effective scale management critical to achieve high hydrocarbon recovery, but even wells at low water cuts were deemed to be at sufficient risk to require squeeze application. Use of conventional, water based squeezes have been known to cause significant damage to productivity in low-watercut wells, including those showing a fines-migration tendency, as was the case here. Hence, on the basis of risk mitigation, supported by an. extensive program of laboratory testing, it was decided that for the initial treatments, only the mainflush would be water based, with a mutual-solvent preflush and marine-diesel overflush. Other key challenges associated with treating from the host included the remote location of the wells, the potential to form hydrates, the cleanliness of the lines along which the treatment would pass, the achievement of effective placement over a long producing interval, as well as the need to deploy the chemical package via a support vessel adjacent to the FPSO. All had to be managed because of the high cost and low availability of a deepwater rig that could deploy the treatments directly to the subsea wellheads. This paper will explore in detail the issues associated with inhibitor-squeeze deployment in deepwater, subsea fields, many of which are currently being developed in the Campos basin, Gulf of Mexico, and West Africa, and are a good example of best-practice sharing from another oil basin. [ABSTRACT FROM AUTHOR]

Barite (BaSO 4 ) is a component of drilling fluids used in the oil and gas industry and may cause barium (Ba) contamination if it is spilled onto flooded soils. Under anoxic soil conditions and low redox potential, sulfate can be reduced to a more soluble form (sulfide), and Ba can be made available. To design a solution for such environmental issues, a field study was conducted in a Ba-contaminated flooded area in Brazil, in which we induced Ba phytoextraction from the management of the planting density of two intercropped macrophytes. Typha domingensis and Eleocharis acutangula were grown in four initial planting densities: "Ld" (low density: 4 and 32 plants m -2 ); "Md" (medium density: 8 and 64 plants m -2 ); "Hd" (high density: 12 and 128 plants m -2 ); "Vhd" (very high density: 16 and 256 plants m -2 ). Vhd produced the largest number of plants after 300 days. However, the treatments did not differ in terms of the amount of biomass. The increments in the initial planting density did not increase the Ba concentration in the aerial part. The greatest Ba phytoextraction (aerial part + root) was achieved by Ld treatment, which removed approximately 3 kg of Ba ha -1 . Md and Vhd treatments had the highest Ba translocation factors. Because more plants per area did not result in greater Ba phytoextraction, a lower planting density was recommended for the intercropping of T. domingensis and E. acutangula to promote the phytoextraction of barium, due to possible lower implementation costs in contaminated flooded environments., Competing Interests: Declaration of Competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)