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Terrestrial shale oil resources in China are abundant. However, its development in China is still in the early stages. And its scale of transformation and production systems is still being explored. Currently, reservoir numerical simulation on shale oil reservoirs faces two main challenges: (1) multiscale flow of matrix–microfracture–hydraulic fractures in shale oil reservoirs and (2) bidirectional coupling of reservoir–wellbore–nozzle systems. This paper proposes a self-flow model for horizontal shale wells that describes multiscale fractures and production controlled by the nozzle. The model integrates the embedded discrete fracture model (EDFM), pipe flow model, and nozzle flow model. The accuracy of the model has been validated through comparisons with other reference models and field data. Then, this study analyzes the effects of different natural fracture densities, horizontal section lengths, number of fracturing stages, and nozzle diameters on the production capacity during the self-flow period. The results indicate that reservoirs with developed natural fractures can enhance the development efficiency during the self-flow period, and appropriate horizontal section lengths and fracturing stages contribute to achieving maximum economic benefits in development. Additionally, smaller nozzle diameters lead to longer self-flow periods and higher cumulative production. The research findings of this paper can be applied to simulate the production of hydraulic fractured horizontal shale wells.

Efficient and sensitive detection of targets is one of the motivations for constant development and innovation of various biosensors. CRISPR-Cas12a, a new generation of gene editing tools, has shown excellent application potential in biosensor design and construction. By combining with the specific recognition element-aptamer, a single-stranded oligonucleotide obtained by systematic evolution of ligands by exponential enrichment (SELEX) in vitro screening, CRISPR-Cas12a also shows superior performance non-nucleic acid targets detection, such as small molecules, proteins, virus and pathogenic bacteria. However, aptamer and CRISPR-Cas12a (CRISPR-Cas12a/Apt) still face some problems in non-nucleic acid target detection, such as single signal response mode and narrow linear range. The development of diverse CRISPR-Cas12a/Apt biosensors is necessary to meet the needs of various detection environments. In this review, the working principle of CRISPR-Cas12a/Apt was introduced and recent progress in CRISPR-Cas12a/Apt in the application of non-nucleic acid target detection was summarized. Moreover, the requirements of critical parameters such as crRNA sequence, activator sequence, and reaction system in the design of CRISPR-Cas12a/Apt biosensors were discussed, which could provide the reference for the design of efficient and sensitive novel non-nucleic acid target biosensors. In addition, the challenges and prospects of CRISPR-Cas12a/Apt-based biosensor were further presented. [ABSTRACT FROM AUTHOR]

The measurement of cardiac troponin I (cTnI) is of vital importance for the early diagnosis of acute myocardial infarction. In this study, an enhanced electrochemiluminescent immunoassay for the highly sensitive and precise determination of cTnI was reported. A biomimetic chip with nepenthes peristome surface microstructures to achieve single-layer microbead arrays and integrated microelectrode arrays (MEAs) for ECL detection was microfabricated. Ru@SiO2 nanoparticles were prepared as signal amplificators labeling immunomagnetic beads. Dendrimer-encapsulated platinum nanoparticles (Pt DENs) were electrochemically modified on ITO MEAs. The resulting Pt DEN-modified ITO MEAs preserved good optical transparency and exhibited an approximately 20-fold ECL signal amplification compared to that obtained from bare ITO. The method made full use of the biomimetic chip with Pt DENs to develop single-layer immunomagnetic bead arrays with increasingly catalyzed electrochemical oxidation of the [Ru(bpy)3]2+–TPA system. Consequently, a limit of detection calculated as 0.38 pg/mL (S/N = 3) was obtained with excellent selectivity, demonstrating significant potential for the detection of cTnI in clinical diagnostics. [ABSTRACT FROM AUTHOR]

To advance oil and gas exploration in the South Yellow Sea Basin, characteristics of Triassic, including its correlation with regional strata, distribution, lithology characteristics, and karst development characteristics, are studied by geological mapping. Results show that there exist Zhouchongcun Formation and Qinglong Formation in the Triassic. Zhouchongcun Formation corresponds to Dongma Formation in the lower Yangtze Region, Badong Formation in the middle Yangtze Region, and Lekoupo Formation in the upper Yangtze region. The upper Qinglong Formation corresponds to the Nanlinghu Formation and Longshan Formation in Xiyanzi district, and Jialingjiang Formation in the middle and upper Yangtze region. Its lithology is limestone, intercalated with marl, mudstone, and argillaceous siltstone. The lower Qinglong Formation corresponds to the Yinkeng Formation at the lower Yangtze group. The lower Qinglong group has the complex lithologic characteristics, which can be divided into six categories from top to bottom, including limestone weathering crust layer, limestone, marl with mudstone, mudstone with limestone, marl with limestone, and mudstone interbedding limestone and mudstone. Karst phenomenon is well developed in the lower Qinglong Formation, and the thickness of weathering crust, revealed by cz35-2-1 well, reaches 60.5 m. Triassic in the South Yellow Sea Basin is mainly distributed in the central uplift and southern depression, showing the regional differences in distribution. Karstification is probably the main reason for this significant difference. Identification of karst phenomenon and stratigraphic division method towards Triassic drilling coring are two important directions of Triassic study in the South Yellow Sea Basin.