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Background Ischemia-reperfusion (IR) induces increased release of extracellular vesicles in the heart and exacerbates myocardial IR injury. We have previously shown that propofol attenuates hypoxia/reoxygenation (HR)-induced injury in human umbilical vein endothelial cells (HUVECs) and that microvesicles derived from propofol-treated HUVECs inhibit oxidative stress in endothelial cells. However, the role of microvesicles derived from propofol post-treated HUVECs ((HR + P)-EMVs) in IR-injured cardiomyocytes is unclear. In this study, we aimed to investigate the role of (HR + P)-EMVs in cardiac IR injury compared to microvesicles derived from hypoxic/reoxygenated HUVECs (HR-EMVs) and to elucidate the underlying mechanisms. Methods Hypoxia/reoxygenation (HR) models of HUVECs and AC16 cells and a mouse cardiac IR model were established. Microvesicles from HR-injured HUVECs, DMSO post-treated HUVECs and propofol post-treated HUVECs were extracted by ultra-high speed centrifugation, respectively. The above EMVs were co-cultured with HR-injured AC16 cells or injected intracardially into IR mice. Flow cytometry and immunofluorescence were used to determine the levels of oxidative stress and apoptosis in cardiomyocytes. Apoptosis related proteins were detected by Western blot. Echocardiography for cardiac function and Evans blue-TTC staining for myocardial infarct size. Expression of lncCCT4-2 in EMVs and AC16 cells was analysed by whole transcriptome sequencing of EMVs and RT-qPCR. The molecular mechanism of inhibition of myocardial injury by (HR + P)-EMVs was elucidated by lentiviral knockdown of lncCCT4-2, plasmid overexpression or knockdown of CCT4, and actinomycin D assay. Results In vitro and in vivo experiments confirmed that HR-EMVs exacerbated oxidative stress and apoptosis in IR-injured cardiomyocytes, leading to increased infarct size and worsened cardiac function. Notably, (HR + P)-EMVs induced significantly less oxidative stress and apoptosis in IR-inju

© 2017. American Geophysical Union. All Rights Reserved. To understand the mineralogical and chemical changes in oil-bearing reservoirs (e.g., depleted oil reservoirs) during massive CO2 injection, we have carried out a core-flooding experimental study of CO2-oil-brine-rock interactions under a simulated reservoir condition of 100°C and 24 MPa. The experimental condition is based on field data from a CO2-EOR project in the southern Songliao Basin. This oil-bearing CO2-flooding experiment used the same experimental setup, reservoir conditions, and workflow as the oil-free experiment reported by Yu et al. (). The sandstone core samples used in the experiment have similar mineralogical compositions as that used in the previous experiment. Compared with the oil-free experiment, the presence of oil appears to substantially reduce the reaction degree between the CO2 fluid and some sensitive minerals. The dissolution rates of the K-feldspar and carbonate minerals for the oil-bearing experiment are 1/5 and 1/4 of that for the oil-free experiments, respectively. For the silicate minerals represented by the K-feldspar, the presence of oil mainly delays the dissolution during the experiment, and reduces the equilibrium dissolution rate. For the carbonate minerals, the presence of oil appears to primarily affect the dissolution at the beginning of the experiments, and reduce the maximum dissolution rate attained. The core permeabilities for the oil-free and oil-bearing cases are both reduced after experiments. The reduction in permeability is probably due to the precipitation of fine siliceous mineral and clay particles released by the dissolution of the carbonate cement, which may clog some pore throats. The results provide some new insights on the fluid-rock interaction during CO2 injection in depleted oil reservoirs or during CO2-EOR.

Accurate prediction of reservoir porosity and permeability is essential for prospecting hydrocarbon reserves and petroleum production capacity. We propose an innovative reservoir porosity and permeability prediction method through identifying sedimentary-diagenetic facies, determining the porosity-permeability trends using core measurement data, extrapolating the spatial distribution of the sedimentary-diagenetic facies using log data through the Bayes discriminant analysis and predicting the reservoir porosity and permeability. The essence of the method was illustrated and its effectiveness was demonstrated using the Eocene beach-bar sandstones in the Dongying Depression, Bohai Bay Basin, eastern China. The Eocene beach bar sandstones are classified into fine sandstone, siltstone, and argillaceous siltstone based on grain sizes, sorting, and matrix contents. The major diagenetic processes that influence the porosity and permeability of the beach-bar sandstones are compaction, carbonate cementation and feldspar dissolution. Seven sedimentary-diagenetic facies were identified in the beach-bar sandstones based on the lithological types, and their corresponding diagenesis and influence extent on reservoir properties. The variation ranges of porosity and permeability (log K) of these sedimentary-diagenetic facies are typically less than 6% and 1.2, respectively. Both the porosity and permeability have well defined functional relationships with depth. The sedimentary-diagenetic facies can be identified effectively from logging data through the use of the Bayes discriminant analysis and corresponding cross-plots. The porosity and permeability (log K) of the well evaluated in the study were predicted with errors in the range of ±3% and ±0.6, respectively, based on the distribution and the fitting equation of the trend lines for the seven sedimentary-diagenetic facies. The predicted porosities and permeability of sedimentary-diagenetic facies match the measured porosities a

CO2 geological sequestration (CGS) in depleted or high-water-cut oil reservoirs is a viable option for reducing anthropogenic CO2 emissions and enhancing oil recovery. The Upper Cretaceous Qingshankou Formation in the central Changling (fault) Depression, Songliao Basin, East China is the selected site for a pilot injection of the CO2 INJECTION project. The target reservoir depth is about 2400–2500 m. Lithologic features and diagenetic minerals of the reservoir and cap rocks have been investigated by optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). In the Qingshankou Formation, the reservoir rock is a typical arkose with moderately to good sorting, and very fine to fine grain sizes. Minerallogically it is dominated by quartz (19–31 vol.%), plagioclase (19–28 vol.%), and K-feldspar (2–26 vol.%). Calcite and ankerite constitute the most common diagenetic minerals. The lithology of the cap rock is mainly silty mudstone and composed of quartz (average of 12.9–27.0 wt.%), albite (14.2–35.5 wt.%), K-feldspar (1.3–2.7 wt.%), mixed-layer illite/smectite (24.9–68.8 wt.%), chlorite (3.15–14.7 wt.%) and some kaolinite. The main antigenic minerals in the CO2 INJECTION well are made up of albite (average of 29.7 wt.%), K-feldspar (average of 4.5 wt.%), calcite (average of 7.5 wt.%) and ankerite (average of 9.1 wt.%).To assess the long-term CO2 EOR-related fluid–rock interaction processes and evaluate the safety of CO2 geological storage in the Qingshankou Formation, reactive geochemical transport simulations using a simple 2D model were performed. The simulation results show that (1) the migration of free CO2 plume did not penetrate the low permeability cap rock after 800 years; (2) ankerite and dawsonite are the major sequestration minerals after CO2 injection, while albite, K-feldspar and calcite are the major dissolution minerals; (3) the sandstone permeability appears to have been reduced more significantly compared to porosity changes aft

CO2-wettability of sandstones is a key variable which determines structural and residual trapping capacities and strongly influences multi-phase fluid dynamics in the rock. An increasing number of researchers has now estimated this wettability by conducting contact angle measurements on quartz, however, there is a large uncertainty associated with the reported data. We demonstrate clearly that the main factor which leads to this broad data spread is due to surface contamination. It is clear that typically inappropriate cleaning methods were used which resulted in artificially high contact angle measurements. We used surface cleaning methods typically prescribed in the surface chemistry community and found that the water contact angle θ on a clean quartz substrate is low, 0–30°, and that θ increases with pressure. We conclude that quartz is strongly water-wet at high pressure conditions.

In grape and some other fruits used for wine making, abscisic acid (ABA) has been demonstrated to be involved in regulating fruit development. ABA metabolism has been characterized in the model plant Arabidopsis thaliana and shown to involve at least three catabolic pathways that inactivate free ABA. Abscisic acid UDP-Glycosyltransferase (ABA-UGT), a member of Glycosyltransferase (GTs) protein family 1, is a key enzyme in the abscisic acid metabolism which leads to the deactivation of ABA. ABA-UGT catalyzes the glucosylation process from abscisic acid to its conjugated metabolite abscisic acid glucose ester (ABA-GE) in planta. ABA-GE is a terminal product of the ABA metabolic pathway and does not appear to have any biological function. Thus, manipulation of ABA-UGT in wine-making fruits will offer a possibility to control the metabolism of ABA with the potential to optimize the ripening of fruit. In this study, genomic and biochemical approaches were used to attempt to identify ABA-UGT in Vitis vinifera, the European grapevine species most widely used in wine making. The identification of ABA-UGT can be a foundation for further research about how ABA is involved in the fruit development and other processes in grapevine.

A data-constrained non-linear optimization approach has been developed to characterize microscopic distributions of mineral phases and pores in a sandstone sample using X-ray CT data sets acquired at 35keV and 45keV beam energies as constraints. The approach minimizes discrepancy between the expected and measured linear absorption coefficients and maximizes Boltzmann distribution probability. It enables integration of both the 3D X-ray CT data-constraints and global level information, and leads to more accurate predictions of microscopic 3D compositional distributions in material samples. Permeability simulations and comparisons with experimentally measured porosity indicate that DCM characterisation agrees reasonably with experimental observations. However, segmentation of CT images leads to under-estimation of porosity and permeability.

X-ray microtomography (micro-CT) with micron resolution enables new ways of characterizing microstructures and opens pathways for forward calculations of multiscale rock properties. A quantitative characterization of the microstructure is the first step in this challenge. We developed a new approach to extract scale-dependent characteristics of porosity, percolation, and anisotropic permeability from 3-D microstructural models of rocks. The Hoshen-Kopelman algorithm of percolation theory is employed for a standard percolation analysis. The anisotropy of permeability is calculated by means of the star volume distribution approach. The local porosity distribution and local percolation probability are obtained by using the local porosity theory. Additionally, the local anisotropy distribution is defined and analyzed through two empirical probability density functions, the isotropy index and the elongation index. For such a high-resolution data set, the typical data sizes of the CT images are on the order of gigabytes to tens of gigabytes; thus an extremely large number of calculations are required. To resolve this large memory problem parallelization in OpenMP was used to optimally harness the shared memory infrastructure on cache coherent Non-Uniform Memory Access architecture machines such as the iVEC SGI Altix 3700Bx2 Supercomputer. We see adequate visualization of the results as an important element in this first pioneering study.

In this study, the effects of CO2 intrusion are investigated quantitatively on reservoir evolution, choosing three factors thought to dominate this process (i.e. detrital mineral assemblage, formation water, and intruded CO2 volume) for sensitivity analysis. Two-dimensional models were constructed to investigate CO2-water-rock reactions and reservoir porosity changes under various conditions. Subsequent to determination of the potential conditions leading to the formation of tight reservoirs, a three-dimensional model was then constructed applying given heterogeneities in porosity, permeability and mineral assemblages to evaluate porosity distribution. Results show that the processes underlying the formation of tight reservoirs are controlled by various factors rather than any single one. Reservoirs containing Ca-rich minerals (i.e. calcite and anorthite) and Ca2+-rich formation water are apt to become tight as a result of CO2 intrusion because of large-scale carbonate precipitation. Although minerals are heterogeneously distributed, they exhibit some similar characteristics as their common ions link them. Results show that it is possible to predict both high-quality and tight reservoirs. In the study area, favourable reservoirs are found in regions with initially high porosity, high permeability and high feldspar mineral contents, while regions that are characterised by low porosity and permeability as well as Ca2+-rich formation water and a high content of Ca-rich minerals tend to become tight after CO2 intrusion., In this study, the effects of CO2 intrusion are investigated quantitatively on reservoir evolution, choosing three factors thought to dominate this process (i.e. detrital mineral assemblage, formation water, and intruded CO2 volume) for sensitivity analysis. Two-dimensional models were constructed to investigate CO2-water-rock reactions and reservoir porosity changes under various conditions. Subsequent to determination of the potential conditions leading to the formation of tight reservoirs, a three-dimensional model was then constructed applying given heterogeneities in porosity, permeability and mineral assemblages to evaluate porosity distribution. Results show that the processes underlying the formation of tight reservoirs are controlled by various factors rather than any single one. Reservoirs containing Ca-rich minerals (i.e. calcite and anorthite) and Ca2+-rich formation water are apt to become tight as a result of CO2 intrusion because of large-scale carbonate precipitation. Although minerals are heterogeneously distributed, they exhibit some similar characteristics as their common ions link them. Results show that it is possible to predict both high-quality and tight reservoirs. In the study area, favourable reservoirs are found in regions with initially high porosity, high permeability and high feldspar mineral contents, while regions that are characterised by low porosity and permeability as well as Ca2+-rich formation water and a high content of Ca-rich minerals tend to become tight after CO2 intrusion.