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Heat flow is a geothermal parameter for indicating the heat source distribution and evaluating geothermal reservoirs. Only 1,230 heat flow points are distributed unevenly in China, mainly concentrated in high‐temperature geothermal and southeast regions. The Songliao Basin is a potential geothermal field in China. Still, only 20 measurement points are known, making evaluating the geothermal genetic mechanism difficult. Sparse data interpolation using deep learning methods is highly accurate and widely used in fields such as image processing. In this work, we propose a deep neural network for predicting heat flow in the Songliao Basin. More than 4,000 global heat flows and 23 geological and geophysical parameters are used as reference constraints for training. The uncertainty error of the prediction is estimated based on the correlation and distance‐based generalized sensitivity analysis. The results show that the maximum heat flow is 85 mW/m2, the average is 67.1 mW/m2, and the error with the measured data is 10.64%. The previous geophysical and geological interpretation results indicate that the heat flow is higher in the west and lower in the east, with high anomalies in the central region, which may be related to the uplift of the deep mantle and the depression of the shallow low‐velocity sedimentary layer. Some high‐temperature melt bodies are in the deep layers, forming the current potential geothermal field. The measured data validates that the DNN is an effective method for predicting regional‐scale heat flow, providing reliable heat source information for evaluating geothermal resources. Plain Language Summary: Geothermal has received extensive global attention as a new renewable energy resource. Geothermal heat flow (GHF) is crucial among various indicators for assessing potential geothermal fields, with over 20,000 measurement points worldwide. However, due to the expensive cost of drilling measurements, the spatial distribution of heat flow points could be more balanced, posing challenges to geothermal exploration and investigation. Traditional heat flow prediction methods rely on interpolation based on sparse measurement points to estimate the regional heat flow distribution. However, spatial variations in the measurement points often affect the prediction results, leading to lower accuracy. Therefore, this study proposes a deep learning approach to establish the complex relationship between heat flow and geological/geophysical features, aiming to estimate the heat flow distribution in the target area. The proposed method has been successfully applied to heat flow prediction in the Songliao Basin, accompanied by an uncertainty analysis technique that provides confidence intervals for the prediction results. These findings offer direct evidence for the geothermal formation mechanisms and thermal evolution laws in the Songliao Basin. Key Points: We propose a deep neural network (DNN) method for predicting terrestrial heat flowCorrelation and Distance‐based Generalized Sensitivity Analysis (DGSA) methods are used to evaluate the uncertainty of DNN predicted heat flow resultsThe prediction of terrestrial heat flow in the Songliao Basin provides direct evidence for deep heat source channels and geothermal genesis mechanisms [ABSTRACT FROM AUTHOR]

Grotto rock structure detection is precondition of the grotto protection and restoration. As a stable and non-destructive geophysical method, electrical resistivity tomography (ERT) is extensively used to detect the geological structure of the grottoes. However, the traditional ERT measurement scheme is challenging to satisfy the requirements of high accuracy and high resolution in the cliff region. Therefore, we propose a new borehole-to-surface-to-cliff ERT (BSC-ERT) scheme for grotto detection. The sensitivity patterns of five ERT schemes using three configurations (A-MN array, AB-MN array, and AM-BN array) are tested to show the detection capability of different configurations. Two numerical experiments show that the combination of borehole-to-surface ERT (BS-ERT) and surface-to-cliff ERT (SC-ERT) schemes using AM-BN array have better imaging effects and a more reasonable detection range, which is recommended to be implemented for future work. In addition, the numerical experiment also proves that the symmetric effect generated in the AM-BN array in BS-ERT scheme can be suppressed with the combination of the SC-ERT scheme. [ABSTRACT FROM AUTHOR]

The spatial distribution of rock fractures during water injection in hot dry rock (HDR) geothermal is essential information for evaluating geothermal well fracturing. The rock fractures produce anisotropic electrical characteristics, which may facilitate geophysical methods for monitoring fracture distribution. This paper studies the anisotropic magnetotelluric (MT) response in water injection fracturing based on the finite difference method (FEM). It uses the residual phase tensor (PT) method to calculate the characteristics of fracture strike and dip angle. The feasibility analysis of the technique under a different angle and resistivity conditions in geothermal reservoir investigation is discussed in detail. The results demonstrate that the MT can explain the characteristics of anisotropic resistivity structure changes from the water injection fracturing of HDR at the 5 km depth. The time-lapse MT monitoring method can provide a reliable scientific basis for fracture distribution direction and spreading characteristics. [ABSTRACT FROM AUTHOR]

Despite the success of animal cloning by somatic cell nuclear transfer (SCNT) in many species, the method is limited by its low efficiency. After zygotic genome activation (ZGA) during mouse development, a large number of endogenous retroviruses (ERVs) are expressed, including the murine endogenous retrovirus‐L (MuERVL/MERVL). In this study, we generate a series of MERVL reporter mouse strains to detect the ZGA event in embryos. We show that the majority of SCNT embryos do not undergo ZGA, and H3K27me3 prevents SCNT reprogramming. Overexpression of the H3K27me3‐specific demethylase KDM6A, but not of KDM6B, improves the efficiency of SCNT. Conversely, knockdown of KDM6B not only facilitates ZGA, but also impedes ectopic Xist expression in SCNT reprogramming. Furthermore, knockdown of KDM6B increases the rate of SCNT‐derived embryonic stem cells from Duchenne muscular dystrophy embryos. These results not only provide insight into the mechanisms underlying failures of SCNT, but also may extend the applications of SCNT. Synopsis: MERVL::tdTomato transgenic mice monitor zygotic genome activation in real time, show that H3K27me3 limits SCNT reprogramming and that KDM6A overexpression or KDM6B knockdown improve the development of SCNT embryos. MERVL::tdTomato transgenic mice can be used to monitor ZGA events in real time.KDM6A and KDM6B functionally compensate each other in SCNT embryos.KDM6A overexpression or KDM6B knockdown improve the development of SCNT embryos. MERVL::tdTomato transgenic mice monitor zygotic genome activation in real time, show that H3K27me3 limits SCNT reprogramming and that KDM6A overexpression or KDM6B knockdown improve the development of SCNT embryos. [ABSTRACT FROM AUTHOR]

Gut microbiota plays a vital role in maintaining the health and immunity of wild birds. However, less is known about the comparison of fecal microbiota between different ecological groups of wild birds, particularly in the Yellow River National Wetland in Baotou, China, an important transit point for birds migrating all over the East Asia-Australian and Central Asian flyways. In this study, we characterized the fecal microbiota and potential microbial function in nine bird species of raptors, waders, and waterfowl using 16S rRNA gene amplicon sequencing to reveal the microbiota differences and interaction patterns. The results indicated that there was no significant difference in α-diversity, but a significant difference in β-diversity between the three groups of birds. The fecal bacterial microbiota was dominated by Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes in all groups of birds. Furthermore, we identified five bacterial genera that were significantly higher in raptors, five genera that were significantly higher in waders, and two genera that were more abundant in waterfowl. The bacterial co-occurrence network results revealed 15 and 26 key genera in raptors and waterfowls, respectively. The microbial network in waterfowl exhibited a stronger correlation pattern than that in raptors. PICRUSt2 predictions indicated that fecal bacterial function was significantly enriched in the antibiotic biosynthesis pathway in all three groups. Metabolic pathways related to cell motility (bacterial chemotaxis and flagellar assembly) were significantly more abundant in raptors than in waders, whereas waders were enriched in lipid metabolism (synthesis and degradation of ketone bodies and fatty acid biosynthesis). The fecal microbiota in waterfowl harbored more abundant vitamin B6 metabolism, RNA polymerase, and tyrosine and tryptophan biosynthesis. This comparative study revealed the microbial community structure, microbial co-occurrence patterns, and potential functions, providing a better understanding of the ecology and conservation of wild birds. Future studies may focus on unraveling metagenomic functions and dynamics along with the migration routine or different seasons by metagenomics or metatranscriptomics., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhao, Liu, Gao and Bai.)

Japanese encephalitis virus (JEV) infection alters microRNA (miRNA) expression in the central nervous system (CNS). However, the mechanism contributing to miRNA regulation in the CNS is not known. We discovered global degradation of mature miRNA in mouse brains and neuroblastoma (NA) cells after JEV infection. Integrative analysis of miRNAs and mRNAs suggested that several significantly downregulated miRNAs and their targeted mRNAs were clustered into an inflammation pathway. Transfection with miRNA 466d-3p (miR-466d-3p) decreased interleukin-1β (IL-1β) expression and inhibited JEV replication in NA cells. However, miR-466d-3p expression increased after JEV infection in the presence of cycloheximide, indicating that viral protein expression reduced miR-466d-3p expression. We generated all the JEV coding proteins and demonstrated NS3 helicase protein to be a potent miRNA suppressor. The NS3 proteins of Zika virus, West Nile virus, and dengue virus serotype 1 (DENV-1) and DENV-2 also decreased miR-466d-3p expression. Results from helicase-blocking assays and in vitro unwinding assays demonstrated that NS3 could unwind pre-miR-466d and induce miRNA dysfunction. Computational models and an RNA immunoprecipitation assay revealed arginine-rich domains of NS3 to be crucial for pre-miRNA binding and degradation of host miRNAs. Importantly, site-directed mutagenesis of conserved residues in NS3 revealed that R226G and R202W reduced the binding affinity and degradation of pre-miR-466d. These results expand the function of flavivirus helicases beyond unwinding duplex RNA to degrade pre-miRNAs. Hence, we revealed a new mechanism for NS3 in regulating miRNA pathways and promoting neuroinflammation. IMPORTANCE Host miRNAs have been reported to regulate JEV-induced inflammation in the CNS. We found that JEV infection could reduce expression of host miRNA. The helicase region of the NS3 protein bound specifically to miRNA precursors and could lead to incorrect unwinding of miRNA precursors, thereby reducing the expression of mature miRNAs. This observation led to two major findings. First, our results suggested that JEV NS3 protein induced miR-466d-3p degradation, which promoted IL-1β expression and JEV replication. Second, arginine molecules on NS3 were the main miRNA-binding sites, because we demonstrated that miRNA degradation was abolished if arginines at R226 and R202 were mutated. Our study provides new insights into the molecular mechanism of JEV and reveals several amino acid sites that could be mutated for a JEV vaccine., (Copyright © 2020 American Society for Microbiology.)

Linoleic acid (18 : 2, n-6) and α-linolenic acid (18 : 3, n-3) are polyunsaturated fatty acids (PUFAs), which are essential for mammalian health, development and growth. However, the majority of mammals, including humans, are incapable of synthesizing n-6 and n-3 PUFAs. Mammals must obtain n-6 and n-3 PUFAs from their diet. Fatty acid desaturase (Fad) plays a critical role in plant PUFA biosynthesis. Therefore, we generated plant-derived Fad3 single and Fad2-Fad3 double transgenic mice. Compared with wild-type mice, we found that PUFA levels were greatly increased in the single and double transgenic mice by measuring PUFA levels. Moreover, the concentration of n-6 and n-3 PUFAs in the Fad2-Fad3 double transgenic mice were greater than in the Fad3 single transgenic mice. These results demonstrate that the plant-derived Fad2 and Fad3 genes can be expressed in mammals. To clarify the mechanism for Fad2 and Fad3 genes in transgenic mice, we measured the PUFAs synthesis-related genes. Compared with wild-type mice, these Fad transgenic mice have their own n-3 and n-6 PUFAs biosynthetic pathways. Thus, we have established a simple and efficient method for in vivo synthesis of PUFAs.

Following fertilization, the zygotic genome is activated through a process termed zygotic genome activation (ZGA), which enables zygotic gene products to replace the maternal products and initiates early embryonic development. During the ZGA period, the embryonic epigenome experiences extensive recodifications. The H3K27me3 demethylase UTX is essential for post-implantation embryonic development. However, it remains unclear whether UTX participates in preimplantation development, especially during the ZGA process. In the present study, we showed that either knockdown or overexpression of UTX led to embryonic development retardation, whereas simultaneous depletion of UTX and overexpression of ZSCAN4D rescued the embryonic development, indicating that UTX positively regulated Zscan4d expression. Using a transgenic mice model, we also found that UTX was required for preimplantation embryonic development. In conclusion, these results indicate that UTX functions as a novel regulator and plays critical roles during ZGA in addition to early embryonic development., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)