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Thermal recovery is one of the most effective techniques for viscous oil production, which has been widely used in the heavy oilfield development. The mechanisms and percolation characteristics of thermal recovery have attracted a lot of attention. However, the displacement characteristics and produced oil properties in the steam flood heavy oil process are rarely addressed. In this paper, steam flooding experiments with two heavy oil viscosities under the temperatures from 120 to 200 °C and velocities from 1 to 3 mL/min were carried out to examine the oil displacement efficiency and the produced oil properties. The results show that the majority of the oil is produced in the low water cut stage. Temperature increment is helpful for prolonging the water breakthrough time. The high injection velocity of steam contributes to a high recovery factor, even if it enters into the high water cut stage. The rheology of the produced oils severely changes because the SARA composition changes, and emulsification occurs during the steam flooding heavy oil process. With the increasing steam temperature, the relative content of resins in the produced oils decreases, and asphaltenes increase. With the increase in the injection volume and the injection velocity of steam, the content of resins and asphaltenes increases. This leads to an increment in the produced oil viscosities. The effect of injection velocity on the rheology properties of the produced oils increases with temperature increment. The finding of this work will provide the technical support for heavy oilfields development. [ABSTRACT FROM AUTHOR]

Compared with a silicon MOSFET device, the SiC MOSFET has many benefits, such as higher breakdown voltage, faster action speed and better thermal conductivity. These advantages enable the SiC MOSFET to operate at higher switching frequencies, while, as the switching frequency increases, the turn-on loss accounts for most of the loss. This characteristic severely limits the applications of the SiC MOSFET at higher switching frequencies. Accordingly, an SRD-type drive circuit for a SiC MOSFET is proposed in this paper. The proposed SRD-type drive circuit can suppress the turn-on oscillation of a non-Kelvin packaged SiC MOSFET to ensure that the SiC MOSFET can work at a faster turn-on speed with a lower turn-on loss. In this paper, the basic principle of the proposed SRD-type drive circuit is analyzed, and a double pulse platform is established. For the purpose of proof-testing the performance of the presented SRD-type drive circuit, comparisons and experimental verifications between the traditional gate driver and the proposed SRD-type drive circuit were conducted. Our experimental results finally demonstrate the feasibility and effectiveness of the proposed SRD-type drive circuit. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease, but its pathogenesis is still unclear. Bioinformatics methods were used to explore the differentially expressed genes (DEGs) and to elucidate the pathogenesis of IPF at the genetic level. The microarray datasets GSE110147 and GSE53845 were downloaded from the Gene Expression Omnibus (GEO) database and analyzed using GEO2R to obtain the DEGs. The DEGs were further analyzed for Gene Ontology (GO) and Kyoto Encyclopedia of Genomes (KEGG) pathway enrichment using the DAVID database. Then, using the STRING database and Cytoscape, a protein–protein interaction (PPI) network was created and the hub genes were selected. In addition, lung tissue from a mouse model was validated. Lastly, the network between the target microRNAs (miRNAs) and the hub genes was constructed with NetworkAnalyst. A summary of 240 genes were identified as DEGs, and functional analysis highlighted their role in cell adhesion molecules and ECM–receptor interactions in IPF. In addition, eight hub genes were selected. Four of these hub genes (VCAM1, CDH2, SPP1, and POSTN) were screened for animal validation. The IHC and RT-qPCR of lung tissue from a mouse model confirmed the results above. Then, miR-181b-5p, miR-4262, and miR-155-5p were predicted as possible key miRNAs. Eight hub genes may play a key role in the development of IPF. Four of the hub genes were validated in animal experiments. MiR-181b-5p, miR-4262, and miR-155-5p may be involved in the pathophysiological processes of IPF by interacting with hub genes. [ABSTRACT FROM AUTHOR]

Rotation and fertilization are important methods used to improve crop yield. In particular, crop rotation is an effective means of enhancing ecosystem diversity; however, there exist relatively few studies regarding the effects of long-term maize–soybean rotation and fertilization on soil microbial communities. To further understand the changes in soil microbial community structure under long-term maize–soybean rotation and fertilization, we used a 9-year-old experimental site with maize–soybean rotation as the research object and soybean continuous cropping as a control. We explored the growth effects of soybean and the changes in soil microbial communities under the soybean–maize rotation system and fertilization treatments by analyzing the physicochemical properties of the soil, crop agronomic traits, yield, and changes in soil microbial community structure. The results show that, in comparison with soybean continuous cropping, the yield of soybeans was increased by 12.11% and 21.42% under maize–soybean rotation with different fertilization treatments, respectively. Additionally, there was a significant increase in the agronomic effects of nitrogen following rotation combined with fertilization. Moreover, the soil pH, SOM, and nutrient status were also improved. Bryobacter, Gemmatimonas, and Rhodanobacter were the dominant bacteria. Rotation treatment increased the relative abundance of Bryobacter and Rhodanobacter, and fertilization treatment increased the relative abundance of Gemmatimonas. Rotation also increased the stability of the bacterial community structure and strengthened the symbiotic relationship between species. The prediction of nitrogen-related functional genes indicates that rotation increased soil ammonification and nitrification. Heterocephalacria and Mrakia were the dominant fungal genera under crop rotation. The abundance of Saccharomyces Mrakia was significantly positively correlated with ammonium nitrogen levels and crop yield. Crop rotation increased the abundance of Saccharomyces Mrakia and reduced the abundance of Fusarium, but fertilization increased the abundance of Fusarium. Functional gene prediction also indicates that the relative abundance of plant pathogens was significantly reduced. This study provides a theoretical basis for soil microbial diversity and ecosystem service function in long-term soybean–maize rotation. [ABSTRACT FROM AUTHOR]

Osteoprotegerin (OPG) is a new member of the tumor necrosis factor (TNF) receptor superfamily, which can inhibit the differentiation and activity of osteoclasts by binding to nuclear factor kappa B receptor activator (RANK) competitively with nuclear factor kappa B receptor activator ligand (RANKL). The previous experiments found that OPG can induce apoptosis of mature osteoclasts in vitro, which can inhibit the activity of mature osteoclasts, thereby exerting its role in protecting bone tissue. In addition, pyroptosis is a new type of cell death that is different from apoptosis. It is unclear whether OPG can induce mature osteoclast pyroptosis and thereby play its role in protecting bone tissue. In this study, the results showed that compared with the control group, the survival rate of osteoclasts in the OPG group was significantly reduced, and the contents of IL-1β, IL-18, and LDH in the supernatant both increased. Many osteoclast plasma membranes were observed to rupture in bright fields, and OPG induced loss of their morphology. Flow cytometry was used to analyze the pyroptosis rate; OPG significantly increased the osteoclast pyroptosis rate. To further reveal the mechanism of OPG-induced osteoclast pyroptosis, we examined the expression level of pyroptosis-related genes and proteins, and the results found that OPG increased the expression of NLRP3, ASC, caspase-1, and GSDMD-N compared with the control group. In summary, OPG can induce osteoclast pyroptosis, and its mechanism is related to the expression levels of ASC, NLRP3, caspase 1 and GSDMD, which were included in the classical pathway of pyroptosis. [ABSTRACT FROM AUTHOR]

Avian influenza A virus H5N1 is a highly pathogenic and persistently a major threat to global health. Vaccines and antibodies targeting hemagglutinin (HA) protein are the primary management strategies for the epidemic virus. Although camelids possess unique immunological features, the immune response induced by specific antigens has not yet been thoroughly investigated. Herein, we immunized an alpaca with the HA antigen of the H5N1 virus and performed single-cell transcriptome profiling for analysis of longitudinal peripheral blood mononuclear cell (PBMCs) behavior using single-cell sequencing technology (scRNA-seq). We revealed multiple cellular immunities during the immunization. The monocytes continued to expand after immunization, while the plasma cells reached their peak three days after the second antigen stimulation. Both monocytes and B cells were stimulated by the HA antigen and produced cell-type-specific cytokines to participated in the immune response. To our knowledge, this is the first study to examine the HA-specific immunological dynamics of alpaca PBMCs at the single-cell level, which is beneficial for understanding the anti-viral immune system and facilitating the development of more potent vaccines and antibodies in camelid animals. [ABSTRACT FROM AUTHOR]

The effective use of nutrient-rich crop straw is an important way to use resources efficiently and to sustain agricultural development. This meta-analysis study collected and analyzed the data of 6788 observations published in 238 peer-reviewed papers to investigate differences in soil C-N fractions and yields of paddy soils under different straw-return amounts. This large dataset was also used to quantify the degree of influence of factors such as climate characteristics, soil properties, N fertilizer application rates, straw-rotting agent addition, rice varieties, and straw return methods. The results showed that straw return amounts improved soil alkaline-hydrolysable N (7%), total N (10%), organic C (11%), the C:N ratio (8%), rice N accumulation (12%), and overall yield (18%). The most significant effect was in northeast China fields for total soil nitrogen (TN) content and yield with increases of 13% and 22%, respectively. We also found more effective N utilization and a greater rice yield when 220–260 kg ha−1 N fertilizer was applied with 20–30 kg ha−1 straw-rotting agent with the total amount of straw return. These findings have important implications for choosing appropriate conditions and field management practices and to improve rice yield in China. [ABSTRACT FROM AUTHOR]

Environmental and occupational exposure to cadmium has been shown to induce kidney damage, liver injury, neurodegenerative disease, and osteoporosis. However, the mechanism by which cadmium induces autophagy in these diseases remains unclear. Studies have shown that cadmium is an effective inducer of oxidative stress, DNA damage, ER stress, and autophagy, which are thought to be adaptive stress responses that allow cells exposed to cadmium to survive in an adverse environment. However, excessive stress will cause tissue damage by inducing apoptosis, pyroptosis, and ferroptosis. Evidently, oxidative stress-induced autophagy plays different roles in low- or high-dose cadmium exposure-induced cell damage, either causing apoptosis, pyroptosis, and ferroptosis or inducing cell survival. Meanwhile, different cell types have different sensitivities to cadmium, which ultimately determines the fate of the cell. In this review, we provided a detailed survey of the current literature on autophagy in cadmium-induced tissue damage. A better understanding of the complex regulation of cell death by autophagy might contribute to the development of novel preventive and therapeutic strategies to treat acute and chronic cadmium toxicity. [ABSTRACT FROM AUTHOR]

The inevitable frequency errors owing to the frequency mismatch of a transmitter and receiver oscillators could seriously deteriorate the imaging performance in distributed inverse synthetic aperture radar (ISAR) system. In this paper, for this issue, a novel method is proposed to calibrate the linear time-varying frequency errors (LTFE) between the transmitting node and the receiving node. The cost function is constructed based on the entropy minimization principle and the problem of LTFE calibration is transformed into cost function optimization. The frequency error coefficient, which minimizes the image entropy, is obtained by searching optimum solution in the solution space of cost function. Then, the original signal is calibrated by the frequency error coefficient. Finally, the effectiveness of the proposed method is demonstrated by simulation and real-data experiments. [ABSTRACT FROM AUTHOR]