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This article discusses a study on bacterial diversity and antibiotic resistance in estuarine sediments in Brazilian coastal areas. The researchers used molecular techniques to study environmental DNA and identify the main phyla of bacteria present, as well as detect the presence of antibiotic resistance genes (ARGs). The study found significant differences in the quantity of ARGs between different sampling points, with some points showing a greater diversity of ARGs than others. The predominant phyla of bacteria found in all samples were Proteobacteria, Actinobacteria, and Firmicutes. The study also identified specific bacteria, such as Enterococcus faecium, Acinetobacter sp, Klebsiella pneumoniae, and Enterobacter cloacae, that are listed for priority surveillance by the World Health Organization. It is important to note that this study is a preprint and has not yet undergone peer review. [Extracted from the article]

2021 MAY 15 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- According to news reporting based on a preprint abstract, our journalists obtained [...]

Primary depositional mineralogy has a major impact on sandstone reservoir quality. The spatial distribution of primary depositional mineralogy in sandstones is poorly understood, and consequently, empirical models typically fail to accurately predict reservoir quality. To address this challenge, we have determined the spatial distribution of detrital minerals (quartz, feldspar, carbonates, and clay minerals) in surface sediment throughout the Ravenglass Estuary, United Kingdom. We have produced, for the first time, high-resolution maps of detrital mineral quantities over an area that is similar to many oil and gas reservoirs. Spatial mineralogy patterns (based on x-ray diffraction data) and statistical analyses revealed that estuarine sediment composition is primarily controlled by provenance (i.e., the character of bedrock and sediment drift in the source area). The distributions of quartz, feldspar, carbonates, and clay minerals are controlled by a combination of the grain size of specific minerals (e.g., rigid vs. brittle grains) and estuarine hydrodynamics. The abundance of quartz, feldspar, carbonates, and clay minerals is predictable as a function of depositional environment and critical grain-size thresholds. This study may be used, by analogy, to better predict the spatial distribution of sandstone composition and thus reservoir quality in ancient and deeply buried estuarine sandstones. [ABSTRACT FROM AUTHOR]

Cancer, Health and Medicine, Life Sciences, Oncology, Risk and Prevention, Toxicology Keywords: Cancer; Health and Medicine; Life Sciences; Oncology; Risk and Prevention; Toxicology EN Cancer Health and Medicine Life Sciences Oncology Risk and Prevention Toxicology 1271 1271 1 03/24/23 20230228 NES 230228 2023 FEB 28 (NewsRx) -- By a News Reporter-Staff News Editor at Cancer Weekly -- Fresh data on toxicology are presented in a new report. According to the news editors, the research concluded: "However, based on the ILCRdermal values obtained, the risk of cancer associated with exposure by dermal contact with the PAHs present in the sediments was moderate, with a mean ILCRdermal value of 2.77 x 10-6. [Extracted from the article]

2019 MAR 2 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- Investigators publish new report on Biology - Marine Biology. According to news [...]

The McMurray Formation of northern Alberta in Canada contains multiscale complex geologic features that were partially formed in a fluvial-estuarine depositional environment. The inclined heterolithic strata deposited as part of fluvial point bars contain continuous centimeter-scale features that are important for flow characterization of steam-assisted gravity drainage processes. These channels are common, extensive, and imbricated over many square kilometers. Modeling the detailed facies in such depositional systems requires a methodology that reflects heterogeneity over many scales. This article presents an object-based facies modeling technique that (1) reproduces the geometry of multiscale geologic architectural elements seen in the McMurray Formation outcrops and provides a grid-free framework that models these geologic objects without relating them to a grid system. The grid-free object-based modeling can be applied to any depositional environment and allows for the complete preservation of architectural information for consistent application to any gridding scheme, local grid refinements, downscaling, upscaling, drape surface, locally variable azimuths, property trend modeling, and flexible model interaction and manipulation. Features millimeters thick or kilometers in extent are represented very efficiently in the same model. [ABSTRACT FROM AUTHOR]

Pleistocene fluvial, estuarine, marine, and deltaic deposition systems were identified in the uppermost 80 m (262 ft) of the central Gulf of Thailand modern continental shelf, situated approximately 70 m (-230 ft) below sea level. Integration of offshore three-dimensional (3-D) seismic reflection data, high-resolution shallow-penetration two-dimensional (2-D) seismic reflection sparker and boomer profiles, and shallow geotechnical borehole measurements enabled the identification of seven depositional sequences. The 3-D plan-view images at successive time slices exhibit single meandering channels (as much as 600 m [1969 ft] wide and channel belts (as much as 10 km [6.2 mi] wide) deposited in the shelf during times of subaerial exposure. Additional geomorphic features imaged include incised valleys, interfluves, oxbow lakes, neck and chute cutoffs, and point-bar meander scrolls showing evidence of expansion and translation. The high-resolution 2-D profiles, with a tuning thickness of approximately 25 cm (~9.8 in.), enabled the discrimination of high-frequency stratigraphic discontinuities (sequence boundaries) and allowed a detailed bed-scale seismic facies characterization of fluvial (point bars), deltaic (clinoforms), estuarine, and marine deposits within a sequence-stratigraphic context. The complete succession shows that most fluvial systems lie within incised valleys in the lower parts of each depositional sequence, fluvial channels show a degradational stacking pattern, and no evidence of fluvial aggradation is observed; aggradation is limited to hemipelagic sedimentation during marine incursions. A shallow (<35 m [<115 ft]) single-story incised valley was described in detail, placing particular emphasis on the recognition criteria and the controls on valley formation and preservation potential of different systems tracts in an inner-shelf location. The 3-D characterization of this system allowed differentiation of sand-prone point-bar deposits and mud-prone abandonment channel facies. The sinuous but continuous mud-filled channel may act as a lateral muddy barrier or baffle that can potentially subdivide a reservoir system into discrete compartments. [ABSTRACT FROM AUTHOR]

Petrophysical properties were determined for six facies in Lower Silurian sandstones of the Appalachian basin: fluvial, estuarine, upper shoreface, lower shoreface, tidal channel, and tidal flat. Fluvial sandstones have the highest permeability for a given porosity and exhibit a wide range of porosity (2-18%) and permeability (0.002-450 md). With a transition-zone thickness of only 1-6 m (3-20 ft), fluvial sandstones with permeability greater than 5 md have irreducible water saturation (Siw) less than 20%, typical of many gas reservoirs. Upper shoreface sandstones exhibit good reservoir properties with high porosity (10-21%), high permeability (3-250 md), and low Siw (<20%). Lower shoreface sandstones, which are finer grained, have lower porosity (4-12%), lower permeability (0.0007-4 md), thicker transition zones (6180 m [20-600 Pc]), and higher Siw. In the tidal-channel, tidal-fiat, and estuarine facies, low porosity (average < 6%), low permeability (average <0.02 md), and small pore throats result in large transition zones (30-200 m; 100-650 Pc) and high water saturations. The most favorable reservoir petrophysical properties and the best estimated production from the Lower Silurian sandstones are associated with fluvial and upper shoreface facies of incised-valley fills, which we interpret to have formed predominantly in areas of structural recesses that evolved from promontories along a collisional margin during the Taconic orogeny. Although the total thickness of the sandstone may not be as great in these areas, reservoir quality is better than in adjacent structural salients, which is attributed to higher energy depositional processes and shallower maximum burial depth in the recesses than in the salients. [ABSTRACT FROM AUTHOR]

The article discusses research on whether human activities endanger estuaries based on the paleoconstruction of estuarine sediments. It references a study by P. I. Macreadie et al published in the journal "Global Change Biology." The authors hypothesized that the increased flow of human-derived nutrients and effluent into estuaries can reduce water quality and promote the growth of undesirable aquatic primary resources, which can change the composition of organic matter within sediments.