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More than 100 million tons of tight oil reserves have been discovered in the Xin’anbian area of the Ordos basin in recent years, of which the main reservoir is the Chang-7 Member of the Yanchang Formation. To identify the characteristics of the tight sandstone reservoir and their the development of the Chang-7 Member in the study area, casting thin sections, scanning electron microscopy (SEM), high-pressure mercury injection, cathodoluminescence and other technical methods were used to analyze the reservoir rock types and their physical properties and pore structure. Based on reservoir diagenesis research and quantitative evaluations of reservoir pores, a reservoir pore evolution mode was established. The results showed that the main rock types in the tight sandstone reservoirs in the Chang-7 Member of the Xin’anbian area were lithic feldspathic sandstone and feldspathic detritus sandstone and that the reservoir space types were mainly feldspar dissolved pores, with a few residual intergranular pores, clay intercrystalline pores, and microfractures. The reservoirs were classified as having low porosity and low permeability and extra-low porosity and extra-low permeability. The porosity and permeability of the reservoirs were between 4 ~ 10% and 0.01 ~ 1 mD, respectively, and were mainly controlled by compaction, cementation, and dissolution. Compaction and cementation reduced the porosity and permeability, while dissolution increased the porosity and permeability. The Chang-7 Member reservoir mainly experienced weak-medium compaction, medium-strong cementation, and different degrees of dissolution. The average loss of porosity due to cementation was around 25%, while the average loss due to compaction was around 13%. This research determined four key stages in the porosity evolution of the Chang-7 Member in the study area: (1) the porosity was reduced to 26% from the Triassic to the Early Jurassic period, which was mainly due to compression compaction; (2) the reservoir was seriously damaged by cementation from the Middle Jurassic to Late Jurassic period, where the porosity decreased to 5%; (3) in the Early Cretaceous period, the porosity increased to 11% due to dissolution; and (4) the porosity was reduced to 7% from the late Early Cretaceous to early Late Cretaceous period, which was mainly due to cementation. [ABSTRACT FROM AUTHOR]

The meteoric diagenetic environment has multiphase characteristic, but the scales of the reservoirs in different meteoric diagenetic environments have been rarely considered. On the basis of geological and well-logging analyses, three distinct phases of the meteoric diagenetic process were observed in the Ordovician of the Jingxi area in Ordos Basin, China. The phreatic zone formed in the first phase is partially preserved, whereas those formed in the second and third phases are completely retained. Strata in the western (close to the Central Uplift Belt) and eastern parts underwent bedding-parallel meteoric dissolution and cross-layer meteoric dissolution, respectively. The distributions of the dissolution formation thicknesses in two successive phases of the meteoric diagenetic process exhibit complementarity at the same positions in the plane. The favorable reservoirs at the top of the Ordovician are mainly distributed in the western parts. The second phase of the meteoric diagenetic process is most conducive to the formation of carbonate reservoirs. By dividing and comparing the multiphases of the meteoric diagenetic environment of carbonates, the favorable karst reservoirs can be predicted in each phase. [ABSTRACT FROM AUTHOR]

The research on cementation periods of deep marine carbonate reservoirs has significance to understand multiphase fluid activities and pore evolution history. Taking the Changxing Formation of the Yuanba area in northeast Sichuan Basin as a case, the formation and distribution characteristics of the reservoir cements were investigated by microscopic observation and fluid inclusions. The results show that the reservoir cements in the Changxing Formation are mainly distributed in intragranular pores, intergranular pores, and fractures in allochemical dolomites and dolomitic biolithite limestones. The cementation of reservoirs can be divided into four periods. In the first period, the intragranular calcite cements and a few non-transformed intergranular calcite cements occurred, which give out dark light or no light under cathodoluminescence, and they had low contents of Fe, Mn, and Ba, and formed in the shallow diagenetic environment. In the second period, the dolomite cements in intergranular pores and fractures occurred, which mainly give out bright light under cathodoluminescence, and they had relatively high contents of Fe, Mn, and S, and relatively low contents of K + Na, Sr, and Ba, and high homogenization temperatures of fluid inclusion, indicating that the cements formed in the middle burial diagenetic environment in early Middle Jurassic. In the third period, the intergranular calcite cements and fracture calcite cements occurred, which mainly give out dark light or no light under cathodoluminescence, and they had high contents of K + Na, Ba, and S, and wide homogenization temperature of fluid inclusion, indicating that the cements formed in the middle-deep burial diagenetic environment in middle-late Middle Jurassic. In the fourth period, the pyrite, quartz, rutile, and strontium minerals occurred, with symbiotic relationship, and they give out no light under cathodoluminescence, and formed in the deep burial environment, perhaps, in the hydrothermal environment. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the role of miR-671-5p in in vitro and in vivo models of ischemic stroke (IS). Middle cerebral artery occlusion and reperfusion (MCAO/R) in C57BL/6 mice as well as oxygen–glucose deprivation and reoxygenation (OGD/R) in a mouse hippocampal HT22 neuron line were used as in vivo and in vitro models of IS injury, respectively. miR-671-5p agomir, miR-671-5p antagomir, pcDNA3.1-NF-κB, and negative controls were transfected into cells using riboFECT CP reagent. miR-671-5p agomir, pcDNA3.1-NF-κB, and negative vectors were administered into MCAO/R mice via intracerebroventricular injection. The results showed that miR-671-5p was significantly downregulated and that miR-671-5p agomir alleviated injury and neuroinflammation induced by ischemic reperfusion. A dual-luciferase reporter assay confirmed that NF-κB is a direct target of miR-671-5p. Reverse experiments showed that miR-671-5p agomir reduced neuroinflammation via suppression of NF-κB expression in both in vitro and in vivo models of IS. Our data suggest that miR-671-5p may be a viable therapeutic target for diminishing neuroinflammation in patients with IS. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s11064-021-03321-1. Correction to: Neurochemical Research (2021) 46:1801-1813 https://doi.org/10.1007/s11064-021-... The original version of the article, Fig. Correction to: miR-671-5p Attenuates Neuroinflammation via Suppressing NF- B Expression in an Acute Ischemic Stroke Model. [Extracted from the article]

Key message: We fine-mapped QBp.caas-3BL for black point resistance in an interval of 1.7 Mb containing five high-confidence annotated genes and developed a KASP marker suitable for selection of QBp.caas-3BL. Wheat black point, which occurs in most wheat-growing regions of the world, is detrimental to grain appearance, processing and nutrient quality. Mining and characterization of genetic loci for black point resistance are helpful for breeding resistant wheat cultivars. We previously identified a major QTL QBp.caas-3BL in a recombinant inbred line (RIL) population of Linmai 2/Zhong 892 across five environments. Here we confirmed the QTL in two additional environments. The genetic region of QBp.caas-3BL was enriched with newly developed markers. Using four sets of near isogenic lines, QBp.caas-3BL was narrowed down to a physical interval of approximately 1.7 Mb, including five annotated genes according to IWGSC reference genome. TraesCS3B02G404300, TraesCS3B02G404600 and TraesCS3B02G404700 were predicted as candidate genes based on the analyses of sequence polymorphisms and differential expression. We also converted a SNP of TraesCS3B02G404700 into a breeding-applicable KASP marker and verified its efficacy for marker-assisted breeding in a panel of germplasm. The findings not only lay a foundation for map-based cloning of QBp.caas-3BL but also provide a useful marker for selection of resistant cultivars genotypes in wheat breeding. [ABSTRACT FROM AUTHOR]

Classification using the l-norm-based representation is usually computationally efficient and is able to obtain high accuracy in the recognition of faces. Among l-norm-based representation methods, linear regression classification (LRC) and collaborative representation classification (CRC) have been widely used. LRC and CRC produce residuals in very different ways, but they both use residuals to perform classification. Therefore, by combining the residuals of these two methods, better performance for face recognition can be achieved. In this paper, a simple weighted sum based fusion scheme is proposed to integrate LRC and CRC for more accurate recognition of faces. The rationale of the proposed method is analyzed. Face recognition experiments illustrate that the proposed method outperforms LRC and CRC. [ABSTRACT FROM AUTHOR]

To study systems-level properties of the cell, it is necessary to go beyond individual regulators and target genes to study the regulatory network among transcription factors (TFs). However, it is difficult to directly dissect the TFs mediated genome-wide gene regulatory network (GRN) by experiment. Here, we proposed a hierarchical graphical model to estimate TF activity from mRNA expression by building TF complexes with protein cofactors and inferring TF's downstream regulatory network simultaneously. Then we applied our model on flower development and circadian rhythm processes in Arabidopsis thaliana. The computational results show that the sequence specific bHLH family TF HFR1 recruits the chromatin regulator HAC1 to flower development master regulator TF AG and further activates AG's expression by histone acetylation. Both independent data and experimental results supported this discovery. We also found a flower tissue specific H3K27ac ChIP-seq peak at AG gene body and a HFR1 motif in the center of this H3K27ac peak. Furthermore, we verified that HFR1 physically interacts with HAC1 by yeast two-hybrid experiment. This HFR1–HAC1–AG triplet relationship may imply that flower development and circadian rhythm are bridged by epigenetic regulation and enrich the classical ABC model in flower development. In addition, our TF activity network can serve as a general method to elucidate molecular mechanisms on other complex biological regulatory processes. Network biology: transcription factor activity network reveals novel pathway Transcription factor and its combinatorial regulations are fundamentally important in coordination among complex regulatory processes. An international team of researchers led by Yong Wang and Luonan Chen at Chinese Academy of Sciences proposed a novel hierarchical graphical model to infer TF activity network from its mRNA expression, protein co-factors, and downstream regulations. The TF mediated genome-wide gene regulatory network reveals HFR1-HAC1-AG pathway regulating circadian rhythm and flower development in Arabidopsis thaliana. This HFR1-HAC1-AG pathway may enrich the classical ABC model in flower development and imply epigenetic regulation via circadian rhythm. The TF activity network can serve as a general method to elucidate molecular mechanisms on other complex biological regulatory processes. [ABSTRACT FROM AUTHOR]