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The continuous rise in hydrocarbon demand, the production decline in conventional oilfields, and the remarkable improvement in extraction methods have allowed the hydrocarbon industry and subsequently, geoscientists, to turn to studies on both unconventional and mature fields with untapped potential. In such reservoirs, the application of advanced drilling, completion, and production techniques must be preceded by the identification of permeable stratigraphic intervals that favour commercial exploitation. Accordingly, bioturbated deposits can play a key role in providing permeable pathways for enhanced production. Herein, we analyse the effects of bioturbation on the porosity and permeability of the Buda Formation, a highly bioturbated, tight (low-porosity matrix) Upper Cretaceous chalk reservoir from the Texas Gulf Coast Basin, which has been commercially exploited because of the occurrence of natural fractures. Our results show that (in addition to the natural fractures) burrows (and borings) substantially increased the porosity and permeability of this formation, thus, potentially contributing to enhanced hydrocarbon (or groundwater) storage and production. These biogenic structures might also have favoured the development of natural fractures and stylolites in the Buda Formation. However, further studies are required to prove this hypothesis. [ABSTRACT FROM AUTHOR]

Background: Microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are the two major antineutrophil cytoplasmic antibody (ANCA)‐associated vasculitis (AAV). Objectives: To characterize a homogenous AAV cohort and to assess the impact of clinicopathological profiles and ANCA serotypes on clinical presentation and prognosis. Clinical differences in GPA patients according to ANCA serotype and the diagnostic yield for vasculitis of biopsies in different territories were also investigated. Results: This retrospective study (2000–2021) included 152 patients with AAV (77 MPA/75 GPA). MPA patients (96.1% myeloperoxidase [MPO]–ANCA and 2.6% proteinase 3 [PR3]–ANCA) presented more often with weight loss, myalgia, renal involvement, interstitial lung disease (ILD), cutaneous purpura, and peripheral nerve involvement. Patients with GPA (44% PR3–ANCA, 33.3% MPO, and 22.7% negative/atypical ANCA) presented more commonly with ear, nose, and throat and eye/orbital manifestations, more relapses, and higher survival than patients with MPA. GPA was the only independent risk factor for relapse. Poor survival predictors were older age at diagnosis and peripheral nerve involvement. ANCA serotypes differentiated clinical features in a lesser degree than clinical phenotypes. A mean of 1.5 biopsies were performed in 93.4% of patients in different territories. Overall, vasculitis was identified in 80.3% (97.3% in MPA and 61.8% in GPA) of patients. Conclusions: The identification of GPA presentations associated with MPO–ANCA and awareness of risk factors for relapse and mortality are important to guide proper therapeutic strategies in AAV patients. Biopsies of different affected territories should be pursued in difficult‐to‐diagnose patients based on their significant diagnostic yield. [ABSTRACT FROM AUTHOR]

Indiana limestone is composed mainly of calcite and aragonite minerals, which are different crystalline forms of calcium carbonate. Due to its composition of almost pure calcium carbonate (around 97%), it is widely used in the petroleum industry as a standard porous media for laboratory experiments with a huge scope in industrial applications. A method to improve oil recovery is associated with the use of nanoparticles (NP). One of the most promising is presented to be that of silica (Si) NP, because of their compatibility with the reservoir and subsurface abundance. In this work, we applied Si NP at a concentration of 0.5%, prepared in a base fluid of 1000 ppm in crude oil, injected in Indiana limestone and tested them with microtomography (microCT) and micro x‐ray fluorescence (microXRF) techniques to evaluate the impact of the treatment. Combining morphological results with the mapping of the elements, a more complete characterization of the sample is possible for a better understanding of these interactions applied in oil field industries. [ABSTRACT FROM AUTHOR]

Bread is one of the oldest foods of mankind, and among them, the sandwich bread is worldwide known and used. In this study we used the non‐destructive computed microtomography technique (microCT) to evaluate the behavior of bread structure over weeks after the production. In addition, the influence of the storage location of the sandwich bread, we performed a comparative analysis between storage at ambient temperature and refrigerated conditions. The analysis of the reconstructed images shows that the bread suffers loss of structure over the weeks. We also have found that keeping the bread refrigerated loses liquid, drying the bread, and thus increasing the loss of its structure. In addition, the porous structure of the bread was evaluated, and a complete characterization of the microstructural changes was performed over time. [ABSTRACT FROM AUTHOR]

In this study, the characterization of the "Santa Luzia" statue was carried out through three non‐destructive X‐ray techniques: X‐ray Fluorescence (XRF), Digital Radiography (DR), and Computed Tomography (CT). The wooden statue dates from the 18th century. It was carved in Portugal and is currently located at the Santa Luzia church—one of the oldest churches built in Rio de Janeiro. The portable XRF system used in this study is composed of an Ag target X‐ray tube and an silicon drift detector detector with energy resolution of 122 eV at 5.9 keV. Several spectra were obtained in different regions of the statue. For the DR and CT evaluations, a portable 120 kV X‐ray tube and a 410 × 410 mm a‐Si flat panel detector with a pixel size of 200 μm were used. Individual radiographs of the parts of the statue were acquired and merged into a single image, in order to show its complete radiography. Finally, the CT images of the head of the statue were taken in angular steps of 2 degrees and, after the reconstruction process, the data were analyzed by means of appropriate software. The elements found in the XRF analysis suggest the presence of the pigments lead white, red lead, zinc white, titanium white, vermilion and emerald green. All of them are in accordance with the pigments used by the artists during the statue's historical period. The 3 exceptions were the zinc white and titanium white pigments, which may be an evidence of modern interventions, and the emerald green pigment, which appears to be a repainting of the green region. The radiographic images showed the manufacturing process of the statue, as well as its structural condition. The assembling of wooden blocks, the presence and type of nails and spikes, and regions of different densities were found in the analysis. In the statue's head, the joining of the face with the main part of the statue is clearly visible, and also the hollow glass eye. The CT analysis was able to better detail this section as a spherical cavity in the central part of the head, as well as the presence of a high‐density fragment inside the hole for the fixation of the aureole. The type of glass eye was identified as blown‐glass eye, which is commonly used in devotional statues. [ABSTRACT FROM AUTHOR]

The culture of coffee is very important in Brazilian scenery. Brazil is the world's largest coffee producer, responsible for 30% of the planet's production, and it is among the 15 largest coffee consuming nations. More and more, consumers look for better quality of coffee, and the presence of determinate composts would prejudice the health of the consumers. Therefore, this study suggests a method to identify and quantify commercially roasted ground coffee impurities/contaminants using computed microtomography (micro‐CT) and x‐ray fluorescence (XRF) techniques. A set of different commercially roasted ground coffees were investigated. The micro‐CT results showed that most of the coffee powder samples analyzed showed some contaminant, and in a specific brand, the amount of contaminants was higher than 9%. The 3D data provided information about the size and shape of these contaminants. The XRF results showed the macro elements P, S, Cl, K, and Ca and the micro elements Mn, Fe, Cu, Zn, Rb, and Sr. The elemental concentrations are in agreement with the values reported in the literature, except for the same specific brand, where the values found were much higher. The combined data of both techniques showed that the amount of impurities/contaminants in the ground coffee results in an increase of the macro and micro nutrients and also modifies the flavor and fragrance of the product, leading to an overall poor quality of the final beverage. [ABSTRACT FROM AUTHOR]

Objective The aim of the present study was to detect preclinical changes in SLE patients in retinal microvascularization or retinal and optical nerve structure by optical coherence tomography. Methods This cross-sectional, single-centre study aimed to describe structural changes [macular and retinal nerve fibre layer (RNFL) thickness] by structural spectral-domain optical coherence tomography (SD-OCT) and perifoveal vascular [vessel density (VD) and vascular perfusion (VP) and foveal avascular zone (FAZ) structural parameters] findings by OCT angiography (OCTA) in 78 SLE patients and 80 healthy volunteers. In addition, we analysed their association with clinical and laboratory parameters, medications received, disease duration, and SLE activity and damage. Results Structural parameters by SD-OCT and perifoveal vascular parameters by OCTA were decreased in SLE patients compared with controls. OCTA parameters (VD, VP and FAZ circularity) and macular thickness were also decreased in patients with longer disease duration (>10 years). The presence of aPLs was associated with a decreased RNFL thickness, mainly in the inferior quadrants. Patients developing APS also showed decreased RNFL thickness and OCTA flow changes. SD-OCT and OCTA results were not associated with disease activity. Foveal structural parameters were lower in patients with higher damage score. Conclusion SD-OCT and OCTA can detect preclinical structural and microcirculatory changes in SLE patients. Structural and perifoveal vascular macular changes in SLE patients are related to disease duration. Macular structural parameters were impaired in patients with higher disease damage. APS seems to be associated with preclinical damage to the optic nerve and impairment of the perifoveal microvasculature. [ABSTRACT FROM AUTHOR]