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With advancements in deep exploration, the deep tight sandstone gas reservoir has become a significant exploration field. However, it remains challenging to develop on a large scale due to the unclear distribution of relatively high-quality reservoirs. In this paper, the petrology, reservoir properties, diagenesis, and structural fracturing of deep tight sandstone reservoirs are systematically studied, focusing on the second member of the Upper Triassic Xujiahe Formation (T3x2) in the Xinchang area, and the types of relatively high-quality reservoirs and their differential controlling are further clarified. According to the matching relationship between pores and fractures, tight sandstone reservoirs can be classified into four types: extremely tight, fractured, porous, and pore-fractured types. Among these, the porous and pore-fractured types are considered effective reservoirs. The formation of tight sandstone reservoirs is closely related to sedimentary microfacies, grain size, diagenesis and tectonic fracturing, with distinct controlling differences across reservoir types. Overall, sedimentary microfacies provide the foundation, while differential diagenesis and tectonic fracturing are the key factors influencing reservoir quality. Among them, the extremely tight sandstone reservoirs can form in various sedimentary microfacies, particularly in medium to fine, lithic-rich sandstones, where strong compaction and cementation are the main factors for the underdevelopment of reservoir space. In contrast, fractured reservoirs mainly form based on porous reservoirs through the superimposition of tectonic fracturing. The porous reservoirs are typically found in relatively high-energy environments such as distributary channels and mouth bars, with medium to coarse feldspar-rich sandstone. Dissolution and chlorite-liner cementation are the key factors for their pore formation. Similarly, pore-fractured reservoirs originate from porous reservoirs that have been further altered by superimposing tectonic fracturing.

Abstract Here, we present the whole genome sequence of Bt S2160-1, a potential alternative to the mosquitocidal model strain, Bti. One chromosome genome and four mega-plasmids were contained in Bt S2160-1, and 13 predicted genes encoding predicted insecticidal crystal proteins were identified clustered on one plasmid pS2160-1p2 containing two pathogenic islands (PAIs) designed as PAI-1 (Cry54Ba, Cry30Ea4, Cry69Aa-like, Cry50Ba2-like, Cry4Ca1-like, Cry30Ga2, Cry71Aa-like, Cry72Aa-like, Cry70Aa-like, Cyt1Da2-like and Vpb4C1-like) and PAI-2 (Cyt1Aa-like, and Tpp80Aa1-like). The clusters appear to represent mosquitocidal toxin islands similar to pathogenicity islands. Transcription/translation of 10 of the 13 predicted genes was confirmed by whole-proteome analysis using LTQ-Orbitrap LC–MS/MS. In summary, the present study identified the existence of a mosquitocidal toxin island in Bacillus thuringiensis, and provides important genomic information for understanding the insecticidal mechanism of B. thuringiensis.

The recent discovery of natural gas within the fifth member of the Xujiahe Formation (T3x5) in the Dongfeng area within the Sichuan Basin highlights the significant exploration potential of this member. However, the unconvincing previous understanding of the sedimentary microfacies, combined with a total lack of studies on the sand body architecture and reservoir distribution, hampers the further exploration of this member. Using core data, log curves, and seismic data, along with sedimentary microfacies analysis, this study investigated the interfaces between the sand bodies of various scales in the Dongfeng area. Furthermore, this study explored the morphological characteristics, types, and stacking patterns of these sand bodies and determined the distributions of sand bodies and reservoirs in the area. The results indicate that the first sand group of the T3x5 member (T3x51) exhibits delta-front deposits, including subaqueous distributary channels, sheet sands, and interdistributary bays. Seven levels of sand body interfaces are identified in the T3x51 sand group. Among them, the interfaces of the first and second levels were identified only in cores, those of the third and fourth levels were recognizable from cores combined with log curves, while those of the fifth, sixth, and seventh levels were distinguishable using seismic data. Three superimposed subaqueous distributary channel complexes are found in the Dongfeng area. Among them, complex 1 in the northwest exhibits the strongest water body energy, while complex 2 in the south displays the weakest. Complex 2 was formed earlier than complexes 1 and 3. Also, complex 1 is further subdivided into three vertically stacked subaqueous distributary channels. The subdivision of sedimentary microfacies in the T3x5 member reveals nine lithofacies types. Among them, stacked pancake-shaped, carbonaceous debris-bearing, massive, and cross-bedded medium-grained sandstones are considered favorable lithofacies. These four lithofacies types exhibit high porosity, as well as low natural gamma-ray (GR) values, low-to-medium deep investigate double lateral resistivity (RD), and high interval transit time (AC) on the log curves. Additionally, the reservoir distribution in the Dongfeng area was delineated based on the characterization of the favorable lithofacies. This study serves as a guide for future exploration and evaluation of the T3x5 member in the Dongfeng area while also augmenting the methodologies for describing tight sandstone reservoirs.

ABSTRACTGenetically modified (GM) soybeans provide a huge amount of food for human consumption and animal feed. However, the possibility of unexpected effects of transgenesis has increased food safety concerns. High-throughput sequencing profiling provides a potential approach to directly evaluate unintended effects caused by foreign genes. In this study, we performed transcriptomic analyses to evaluate differentially expressed genes (DEGs) in individual soybean tissues, including cotyledon (C), germ (G), hypocotyl (H), and radicle (R), instead of using the whole seed, from four GM and three non-GM soybean lines. A total of 3,351 DEGs were identified among the three non-GM soybean lines. When the GM lines were compared with their non-GM parents, 1,836 to 4,551 DEGs were identified. Furthermore, Gene Ontology (GO) analysis of the DEGs showed more abundant categories of GO items (199) among non-GM lines than between GM lines and the non-GM natural varieties (166). Results of Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that most KEGG pathways were the same for the two types of comparisons. The study successfully employed RNA sequencing to assess the differences in gene expression among four tissues of seven soybean varieties, and the results suggest that transgenes do not induce massive transcriptomic alterations in transgenic soybeans compared with those that exist among natural varieties. This work offers empirical evidence to investigate the genomic-level disparities induced by genetic modification in soybeans, specifically focusing on seed tissues.

The Xujiahe Formation in the western Yuanba area of the northeastern Sichuan Basin was slightly affected by late tectonic activity and thus has fewer fractures relative to the central and eastern Yuanba areas. Utilizing core observation, slice identification, logging interpretation, and inclusion analysis, the characteristics and controlling factors of fractures in tight sandstone of the Xujiahe Formation of the western Yuanba area were analyzed.The results show that the study area mainly contains low-angle shear fractures and diagenetic fractures. Fractures in the 2nd and 3rd members of the Xujiahe Formation were primarily filled by calcite and clay respectively. The fractures in the Xujiahe Formation of the study area can be classified into three stages, corresponding to the regional tectonic deformations during the Late Jurassic, the end of the Early Cretaceous, and the Late Himalayan. The fractures of the 1st and 2nd stages were fully or partly filled, but the 3rd stage fracture was not filled. The development of fractures was mainly affected by the fault and fold deformation strength, lithology combination, and stratum thickness. Fractures in the hinge zone and southeast limb of Jiulongshan anticline were mainly generated by bending deformation except for the fault zone. The fault-related fracture was more plentiful in the vicinity of the fault zone. Both bending deformation fracture and fault-related fracture are favorable for petroleum development. Fractures in the conglomerate of 3rd Member of the Xujiahe Formation can terminate at or transect the gravel particle and generally show small apertures. The low-angle fractures and micro-fractures in the quartz sandstones of the 2nd Member of the Xujiahe Formation developed aligning with bedding. Both the 3rd and 2nd members of the Xujiahe Formation in the study area are favorable targets for petroleum exploration and development.

Through comprehensively applying geological and geophysical data, as well as core and thin section observation, the characteristics of reservoirs and fractures in the second member of the Xujiahe Formation (hereinafter referred to as Xu2 Member) in the Yuanba area, northern Sichuan Basin, were studied. Combined with the analysis of the main controlling factors of production capacity, the types and characteristics of the sweet spots in the tight sandstone gas reservoir were determined. The evaluation standards and geological models of the sweet spots were established. The results are as follows: (1) There are bedding-parallel fracture-, fault-induced fracture-, and pore-dominated sweet spots in the tight sandstone gas reservoirs of the Xu2 Member. (2) The bedding parallel fracture-dominated sweet spots have developed in quartz sandstones with well-developed horizontal fractures and micro-fractures. They are characterized by high permeability and high gas output during production tests. This kind of sweet spots is thin and shows a limited distribution. Their logging responses show extremely low gamma-ray (GR) values and medium-high AC values. Moreover, the bedding parallel fracture-dominated sweet spots can be mapped using seismic methods. (3) The fault-induced fracture-dominated sweet spots have well-developed medium- and high-angle shear fractures. Their logging responses show an increase in peaks of AC values and total hydrocarbon content and a decrease in resistivity. Seismically, the areas with well-developed fault-induced fracture-dominated sweet spots can be effectively mapped using the properties such as seismic entropy and maximum likelihood. (4) The pore-dominated sweet spots are developed in medium-grained feldspathic litharenites with good reservoir properties. They are thick and widely distributed. (5) These three types of sweet spots are mainly determined by sedimentation, diagenesis, and tectonism. The bedding parallel fracture-dominated sweet spots are distributed in beach-bar quartz sandstones on the top of the 1st sand layer group in the Xu2 Member, which develops in a shore-shallow lake environment. The fault-induced fracture-dominated sweet spots mainly occur near faults. They are increasingly developed in areas closer to faults. The pore-dominated sweet spots are primarily distributed in the 2nd and 3rd sand layer groups, which lie in the development areas of distributary channels near provenances at western Yuanba area. Based on the geological and seismic data, a comprehensive evaluation standard for these three types of sweet spots of the tight sandstone reservoirs in the Xu2 Member has been established, which, on the one hand, lays the foundation for the development and evaluation of the gas reservoir, and on the other hand, deepens the understanding of sweet spot in the tight sandstone gas reservoirs.

Abstract Background Widely targeted metabolomics was applied to estimate the differences in the metabolite profiles of maize seeds from 3 natural genotypic varieties and 4 genetically modified (GM) lines. Results Pairwise comparison with their isogenic controls revealed 71, 121, 43 and 95 differentially accumulated metabolites (DAMs) in GM maize seeds of C0030.2.4, C0030.3.5, C0010.1.1 and C0010.3.1, respectively. KEGG pathway enrichment analysis showed that most of these DAMs participated in the biosynthesis of secondary metabolites and purine metabolism in GM maize C0030.2.4 and C0030.3.5, but participated in tryptophan metabolism and 2-oxocarboxylic acid metabolism in C0010.3.1 seeds and in metabolic pathways and the biosynthesis of secondary metabolites in C0010.1.1 seeds. The data also showed that the differences in metabolite accumulation, both total DAMs and co-DAMs, among the different natural genotypic varieties (418 DAMs and 39 co-DAMs) were greater than those caused by genetic modification (330 DAMs and 3 co-DAMs). Conclusions None of the DAMs were identified as new or unintended, showing only changes in abundance in the studied maize seeds. The metabolite profile differences among the 3 non-GM lines were more notable than those among GM lines. Different genetic backgrounds affect metabolite profiling more than gene modification itself. Graphic abstract

By using core, logging curves, and experiment data, favorable lithofacies types in the 2nd Member of Triassic Xujiahe Formation in the Xinchang area, Sichuan Basin were classified, standard of the favorable lithofacies was established, planar distribution regularities of the favorable lithofacies were identified, and forming mechanisms of the favorable lithofacies and their control effect on production were examined. (1) The 2nd Member of Xujiahe Formation has twelve types of lithofacies, among which multiple layer medium-coarse grain sandstone lithofacies, parallel bedding medium-coarse grain sandstone lithofacies, massive bedding medium-coarse grain sandstone lithofacies, inclined bedding medium-coarse grain sandstone lithofacies, and charcoal-bearing medium-coarse grain sandstone lithofacies with better physical properties and higher gas content are favorable lithofacies; they feature low gamma, low neutron porosity, low resistivity, and high acoustic travel time on logging curves. (2) The sedimentary process controls spatial distribution of sand bodies which are the material basis of the favorable lithofacies; post diagenetic fluids would differentially reconstruct the favorable lithofacies; tectonic activities and abnormal formation pressure made strata slide along the weakness plane, giving rise to fractures in different types of rocks, which can enhance the reservoir permeability significantly. (3) The development degree of favorable lithofacies is a major factor affecting stable production of gas well.

Label-free quantitative proteomic (LFQ) and widely targeted metabolomic analyses were applied in the safety evaluation of three genetically modified (GM) maize varieties, BBL, BFL-1, and BFL-2, in addition to their corresponding non-GM parent maize. A total of 76, 40, and 25 differentially expressed proteins (DEPs) were screened out in BBL, BFL-1, and BFL-2, respectively, and their abundance compared was with that in their non-GM parents. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that most of the DEPs participate in biosynthesis of secondary metabolites, biosynthesis of amino acids, and metabolic pathways. Metabolomic analyses revealed 145, 178, and 88 differentially accumulated metabolites (DAMs) in the BBL/ZH58, BFL-1/ZH58, and BFL-2/ZH58×CH72 comparisons, respectively. KEGG pathway enrichment analysis showed that most of the DAMs are involved in biosynthesis of amino acids, and in arginine and proline metabolism. Three co-DEPs and 11 co-DAMs were identified in the seeds of these GM maize lines. The proteomic profiling of seeds showed that the GM maize varieties were not dramatically different from their non-GM control. Similarly, the metabolomic profiling of seeds showed no dramatic changes in the GM/non-GM maize varieties compared with the GM/GM and non-GM/non-GM maize varieties. The genetic background of the transgenic maize was found to have some influence on its proteomic and metabolomic profiles.

The phosphinothricin N-acetyltransferase gene (pat) is widely used to confer resistance to the herbicide phosphinothricin for genetically modified (GM) crops. A quantitative sandwich enzyme-linked immunosorbent assay (ELISA) is developed to detect PAT/pat in GM crops. Two anti-PAT/pat monoclonal antibodies (mAbs), 1F5-1F2 and 1B6-2D3, with titers of 1:1,024,000 and 1:896,000, respectively, against overexpressed His-PAT/pat, were screened out, raised, and characterized. An ELISA method was established with the 1F5-2F2 mAb for capture and the biotin-labeled 1B6-2D3 mAb for detection of PAT/pat. The linear detection range of the method was approximately 1.5625–12.5 ng/mL, with a sensitivity of 0.085 ng/mL and a coefficient of variation (CV) less than 5.0%. No cross-reactivity was found with other herbicide resistance proteins, especially PAT/bar. The established sensitive and specific ELISA was successfully applied in the detection of PAT/pat expression in GM crops.

Abstract As a high-resolution geophysical method employed by the oil and gas industry, well logging can be used to accurately investigate reservoirs. Challenges associated with shale gas reservoir exploration increase the importance of applying elastic parameters or velocity at the logging scale. An efficient shale rock physics model is the foundation for the successful application of this method. We propose a procedure for modelling shale rock physics in which an appropriate modelling method is applied for different compositions of shale rock. The stiffnesses of the kerogen and fluid (oil, gas or water) mixture are obtained with the Kuster-Toksöz model, which assumes that the fluid is included in the kerogen matrix. A self-consistent approximation method is used to model clay, where the clay pores are filled with formation water. The Backus averaging model is then used to simulate the influence of laminated clay and laminated kerogen. Elastic parameter simulations using well logging data show the importance of treating the volume fractions of laminated clay and kerogen carefully. A comparison of the measured compressional slowness and modelled compressional slowness shows the efficiency of the proposed modelling procedure.

Background Injection of adipose-derived stem cells (ASCs) is a promising treatment for facial contour deformities. However, its treatment mechanisms remain largely unknown. The study aimed to explain the molecular mechanisms of adipogenic differentiation from ASCs based on the roles of long noncoding RNAs (lncRNAs). Methods Datasets of mRNA–lncRNA (GSE113253) and miRNA (GSE72429) expression profiling were collected from Gene Expression Omnibus database. The differentially expressed genes (DEGs), lncRNAs (DELs) and miRNAs (DEMs) between undifferentiated and adipocyte differentiated human ASCs were identified using the Linear Models for Microarray Data method. DELs related co-expression and competing endogenous RNA (ceRNA) networks were constructed. Protein–protein interaction (PPI) analysis was performed to screen crucial target genes. Results A total of 748 DEGs, 17 DELs and 51 DEMs were identified. A total of 13 DELs and 279 DEGs with Pearson correlation coefficients > 0.9 and p-value < 0.01 were selected to construct the co-expression network. A total of 151 interaction pairs among 112 nodes (10 DEMs; eight DELs; 94 DEGs) were obtained to construct the ceRNA network. By comparing the lncRNAs and mRNAs in two networks, five lncRNAs (SNHG9, LINC02202, UBAC2-AS1, PTCSC3 and myocardial infarction associated transcript (MIAT)) and 32 genes (i.e., such as phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), protein tyrosine phosphatase receptor type B (PTPRB)) were found to be shared. PPI analysis demonstrated PIK3R1 , forkhead box O1 (FOXO1; a transcription factor) and estrogen receptor 1 (ESR1) were hub genes, which could be regulated by the miRNAs that interacted with the above five lncRNAs, such as LINC02202-miR-136-5p-PIK3R1, LINC02202-miR-381-3p-FOXO1 and MIAT-miR-18a-5p-ESR1. LINC02202 also could directly co-express with PIK3R1. Furthermore, PTPRB was predicted to be modulated by co-expression with LINC01119. Conclusion MIAT, LINC02202 and LINC01119 may be potentially important, new lncRNAs associated with adipogenic differentiation of ASCs. They may be involved in adipogenesis by acting as a ceRNA or co-expressing with their targets.

We have reported on the lateral photovoltaic effect of LaTiO3 films epitaxially grown on (100) SrTiO3 substrates. Under illumination of continuous 1064 nm laser beam on the LaTiO3 film through SrTiO3 substrate, the open-circuit photovoltage depended linearly on the illuminated position. The photosensitivity can be modified by bias current. These results indicated that the LaTiO3 films give rise to a potentially photoelectronic device for near infrared position-sensitive detection.

Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification and detection technology that enables the amplification of DNA within 30 min at a constant temperature of 37-42 °C by simulating in vivo DNA recombination. In this study, based on the regulatory sequence of the cauliflower mosaic virus 35S (CaMV-35S) promoter and the Agrobacterium tumefaciens nopaline synthase gene (nos) terminator, which are widely incorporated in genetically modified (GM) crops, we designed two sets of RPA primers and established a real-time RPA detection method for GM crop screening and detection. This method could reliably detect as few as 100 copies of the target molecule in a sample within 15-25 min. Furthermore, the real-time RPA detection method was successfully used to amplify and detect DNA from samples of four major GM crops (maize, rice, cotton, and soybean). With this novel amplification method, the test time was significantly shortened and the reaction process was simplified; thus, this method represents an effective approach to the rapid detection of GM crops. [ABSTRACT FROM AUTHOR]

Reference plasmids are an essential tool for the quantification of genetically modified (GM) events. Quantitative real-time PCR (qPCR) is the most commonly used method to characterize and quantify reference plasmids. However, the precision of this method is often limited by calibration curves, and qPCR data can be affected by matrix differences between the standards and samples. Here, we describe a digital PCR (dPCR) approach that can be used to accurately measure the novel reference plasmid pKefeng6 and quantify the unauthorized variety of GM rice Kefeng6, eliminating the issues associated with matrix effects in calibration curves. The pKefeng6 plasmid was used as a calibrant for the quantification of Kefeng6 rice by determining the copy numbers of event-(77 bp) and taxon-specific (68 bp) fragments, their ratios, and their concentrations. The plasmid was diluted to five different concentrations. The third sample (S3) was optimized for the quantification range of dPCR according to previous reports. The ratio between the two fragments was 1.005, which closely approximated the value certified by sequencing, and the concentration was found to be 792 copies/μL. This method was precise, with an RSD of ~3%. These findings demonstrate the advantages of using the dPCR method to characterize reference materials. [ABSTRACT FROM AUTHOR]

We have reported on the lateral photovoltaic effect of LaTiO3 films epitaxially grown on (100) SrTiO3 substrates. Under illumination of continuous 1064nm laser beam on the LaTiO3 film through SrTiO3 substrate, the open-circuit photovoltage depended linearly on the illuminated position. The photosensitivity can be modified by bias current. These results indicated that the LaTiO3 films give rise to a potentially photoelectronic device for near infrared position-sensitive detection. [ABSTRACT FROM AUTHOR]