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Laboratory experiments, numerical simulations and fracturing technology were combined to address the problems in shale oil recovery by CO2 injection. The laboratory experiments were conducted to investigate the displacement mechanisms of shale oil extraction by CO2 injection, and the influences of CO2 pre-pad on shale mechanical properties. Numerical simulations were performed about influences of CO2 pre-pad fracturing and puff-n-huff for energy replenishment on the recovery efficiency. The findings obtained were applied to the field tests of CO2 pre-pad fracturing and single well puff-n-huff. The results show that the efficiency of CO2 puff-n-huff is affected by micro- and nano-scale effect, kerogen, adsorbed oil and so on, and a longer soaking time in a reasonable range leads to a higher exploitation degree of shale oil. In the “injection + soaking” stage, the exploitation degree of heavy hydrocarbons is enhanced by CO2 through its effects of solubility-diffusion and mass-transfer. In the “huff” stage, crude oil in large pores is displaced by CO2 to surrounding larger pores or bedding fractures and finally flows to the production well. The injection of CO2 pre-pad is conducive to keeping the rock brittle and reducing the fracture breakdown pressure, and the CO2 is liable to filter along the bedding surface, thereby creating a more complex fracture. Increasing the volume of CO2 pre-pad can improve the energizing effect, and enhance the replenishment of formation energy. Moreover, the oil recovery is more enhanced by CO2 huff-n-puff with the lower shale matrix permeability, the lower formation pressure, and the larger heavy hydrocarbon content. The field tests demonstrate a good performance with the pressure maintained well after CO2 pre-pad fracturing, the formation energy replenished effectively after CO2 huff-n-puff in a single well, and the well productivity improved.

The integrated simulation and optimization technology of reservoir-wellbore-pipe network is developed to reflect the mutual influence and restriction among reservoir engineering, oil production engineering and surface engineering, and to obtain the scheme with minimum conflict and optimal benefit in each step. This technology is based on the concept of global optimization to maximize production and profit, reduce costs and increase benefit. This paper elaborates the current situation of integrated simulation technology of reservoir-wellbore-pipe network both at home and abroad, discusses its correlation with the primary business of Sinopec and its development from three aspects of modeling, cloud platform and intellectualization. Suggestions on its future development are put forward from underlying data, software platform, popularization and application, and cross-border integration to provide means and guidance for the construction of intelligent oil and gas fields. The results show that the integrated simulation of reservoir-wellbore-pipe network can better reflect the optimization requirements of each step, avoid the ineffective operation of field equipment, and effectively improve the efficiency of research and management. Coupling solution, global optimization method and pressure fitting, which can make the simulation results reflect the real situation, are the key technologies for the network. The theoretical technology and main function research of integrated simulation technology have been mature, but the large-scale application and local function improvement of oil and gas fields are yet to be promoted. In the future, the integrated simulation of reservoir-wellbore-pipe network will develop from digitalization to modeling and intellectualization, from local simulation to cloud computing, and from manual intervention to intelligent decision-making. We suggest speeding up the construction of the unified database and model base of the whole underlying platform, strengthening the construction of software integration and integration platform with independent intellectual property rights, speeding up the popularization and application of intelligent oil and gas field demonstration projects, and strengthening the integration of oil and gas industry with artificial intelligence (AI), big data and block chain for its development.

Summary: Our understanding of human fetal cerebellum development during the late second trimester, a critical period for the generation of astrocytes, oligodendrocytes, and unipolar brush cells (UBCs), remains limited. Here, we performed single-cell RNA sequencing (scRNA-seq) in human fetal cerebellum samples from gestational weeks (GWs) 18–25. We find that proliferating UBC progenitors distribute in the subventricular zone of the rhombic lip (RLSVZ) near white matter (WM), forming a layer structure. We also delineate two trajectories from astrogenic radial glia (ARGs) to Bergmann glial progenitors (BGPs) and recognize oligodendrogenic radial glia (ORGs) as one source of primitive oligodendrocyte progenitor cells (PriOPCs). Additionally, our scRNA-seq analysis of the trisomy 21 fetal cerebellum at this stage reveals abnormal upregulated genes in pathways such as the cell adhesion pathway and focal adhesion pathway, which potentially promote neuronal differentiation. Overall, our research provides valuable insights into normal and abnormal development of the human fetal cerebellum.

Abstract Masquerade is a form of camouflage in which animals use their body size, shape, and coloration to resemble inanimate objects in their environment to deceive predators. However, there is a lack of experimental evidence to show that animals actively choose objects that match these body parameters. To explore how the Hainan four‐eyed turtle, Sacalia insulensis, masquerades using suitable stones, we used indoor video surveillance technology to study the preferences of juvenile S. insulensis for stones of different sizes, shapes, and colors. The results indicated that under normal conditions, during the day, juvenile S. insulensis preferred larger oval or round stones, while at night, they preferred oval stones that were closer to their own size, with no significant preference for stone color during either time. When disturbed (by a researcher swinging their arm back and forth above the experimental setup every hour to mimic a predator), the turtles showed a preference for brown stones that were closer to their size and oval in shape. These findings suggest that juvenile S. insulensis prefer stones that resemble their carapace size and shape to masquerade when undisturbed, and that this preference is reinforced when they masquerade to reduce the risk of predation. The preference for stones that resemble their carapace color is significant only when there is a disturbance. To the best of our knowledge, this is the first study to provide evidence that vertebrates can selectively choose objects that resemble their own morphology for masquerading to reduce predation risk.

Abstract Animal camouflage serves a dual purpose in that it enhances both predation efficiency and anti‐predation strategies, such as background matching, disruptive coloration, countershading, and masquerade, for predators and prey, respectively. Although body size and shape determine the appearance of animals, potentially affecting their camouflage effectiveness, research over the past two centuries has primarily focused on animal coloration. Over the past two decades, attention has gradually shifted to the impact of body size and shape on camouflage. In this review, we discuss the impact of animal body size and shape on camouflage and identify research issues and challenges. A negative correlation between background matching effectiveness and an animal's body size has been reported, whereas flatter body shapes enhance background matching. The effectiveness of disruptive coloration is also negatively correlated with body size, whereas irregular body shapes physically disrupt the body outline, reducing the visibility of true edges and making it challenging for predators to identify prey. Countershading is most likely in larger mammals with smaller individuals, whereas body size is unrelated to countershading in small‐bodied taxa. Body shape influences a body reflectance, affecting the form of countershading coloration exhibited by animals. Animals employing masquerade achieve camouflage by resembling inanimate objects in their habitats in terms of body size and shape. Empirical and theoretical research has found that body size affects camouflage strategies by determining key aspects of an animal's appearance and predation risk and that body shape plays a role in the form and effectiveness of camouflage coloration. However, the mechanisms underlying these adaptations remain elusive, and a relative dearth of research on other camouflage strategies. We underscore the necessity for additional research to investigate the interplay between animal morphology and camouflage strategies and their coevolutionary development, and we recommend directions for future research.

An accurate mapping and understanding of remaining oil distribution is very important for water control and stabilize oil production of mature oilfields in ultra-high water-cut stage. Currently, the Tuo-21 Fault Block of the Shengtuo Oilfield has entered the stage of ultra-high water cut (97.2%). Poor adaptability of the well pattern, ineffective water injection cycle and low efficiency of engineering measures (such as workover, re-perforation and utilization of high-capacity pumps) are the significant problems in the ultra-high water-cut reservoir. In order to accurately describe the oil and water flow characteristics, relative permeability curves at high water injection multiple (injected pore volume) and a semi-quantitative method is applied to perform fine reservoir simulation of the Sand group 3–7 in the Block. An accurate reservoir model is built and history matching is performed. The distribution characteristics of remaining oil in lateral and vertical directions are quantitatively simulated and analyzed. The results show that the numerical simulation considering relative permeability at high injection multiple can reflect truly the remaining oil distribution characteristics after water flooding in an ultra-high water-cut stage. The distribution of remaining oil saturation can be mapped more accurately and quantitatively by using the ‘four-points and five-types’ classification method, providing a basis for potential tapping of various remaining oil types of oil reservoirs in late-stage of development with high water-cut.

The Triassic massive sandstone reservoir in the Tahe oilfield has a strong bottom-water drive and is characterized by great burial depth, high temperature and salinity, a thin pay zone, and strong heterogeneity. At present, the water-cut is high in each block within the reservoir; some wells are at an ultra-high water-cut stage. A lack of effective measures to control water-cut rise and stabilize oil production have necessitated the application of enhanced oil recovery (EOR) technology. This paper investigates the development and technological advances for oil reservoirs with strong edge/bottom-water drive globally, and compares their application to reservoirs with characteristics similar to the Tahe oilfield. Among the technological advances, gas injection from the top and along the direction of structural dip has been used to optimize the flow field in a typical bottom-water drive reservoir. Bottom-water coning is restrained by gas injection-assisted water control. In addition, increasing the lateral driving pressure differential improves the plane sweep efficiency which enhances oil recovery in turn. Gas injection technology in combination with technological measures like channeling prevention and blocking, and water plugging and profile control, can achieve better results in reservoir development. Gas flooding tests in the Tahe oilfield are of great significance to identifying which EOR technology is the most effective and has the potential of large-scale application for improving development of deep reservoirs with a strong bottom-water drive.

The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle model. With the new model, the statistical correspondence between the production decline stage and the reserve-production imbalance is clarified, and the correlation of water cut with the recovery percent of recoverable reserves is discussed, providing quantitative basis of reservoir engineering for dividing development stages of oilfield and defining mature oilfields. According to the statistics of oilfields in eastern China, the time point corresponding to the reserve-production balance coefficient dropping to less than 1 dramatically is well correlated the beginning point of production decline, thus the time when the reserve-production balance coefficient drops dramatically can be taken as the initiation point of production decline stage. The research results show that the water cut and the recovery percent of recoverable reserves have a good statistical match in the high water cut stage, and it is more rational to take both the start point of production decline stage and the water cut of 90% (or the recovery percent of recoverable reserves of 80%) as the critical criteria for defining a mature oilfield. Five production evolution patterns can be summarized as follows: growth—peak plateau—stepped decline, growth—stepped stabilizing—stepped decline, growth—stepped stabilizing—rapid decline, growth—peak plateau—rapid decline, and growth—continuous decline.

Objective: The mechanism by which Notopterygium (NE) regulates the nucleotide‐binding, oligomerization domain (NOD)‐like receptor family and pyrin domain-containing 3 (NLRP3) inflammasome to treat rheumatoid arthritis (RA) was investigated to reveal the scientific implications of NE in RA treatment. Methods: Adjuvant arthritis (AA) rats were replicated. After NE intervention, the anti-inflammatory efficacy of NE in vivo was determined. The mechanism of NE in RA treatment was predicted by network pharmacology, and the key target for further experiments was found through the analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG). The effect of NE on the NLRP3 inflammasome in AA rats was verified. Furthermore, with the induction of inflammation in RAW264.7 cells by lipopolysaccharide (LPS), several techniques, such as Griess assay, enzyme linked immunosorbent assays, electron microscopy, and fluorescence probe technology, were used to investigate the anti-inflammatory and related mechanisms of NE in RA treatment. Results: NE could inhibit inflammation in AA rats. KEGG results showed that NLRP3 participated in the top three pathways of NE in RA treatment. Through Western blotting and immunofluorescence assays, this study demonstrated that NE can regulate NLRP3, pro-Caspase-1, Caspase-1, and CD11b in the ankle joint of AA rats. NE may significantly reduce the LPS-induced inflammatory response of RAW264.7 cells by alleviating mitochondrial damage, reducing the number of mitochondrial deoxyribonucleic Acid and mitochondrial reactive oxygen species, inhibiting NLRP3 inflammasome activation. Conclusion: The anti-inflammatory and antirheumatic effect of NE may involve regulating NLRP3 inflammasome activation through mitochondria. NLRP3 is probably the key target molecule of NE in the treatment of RA.

On the scientific basis, the carbon sink estimation of wetland was summarized up, that is stock-difference method and gain–loss method as a fundamental approach. The major issues when those methods were applied in that estimation had been raised up for attention to be paid. Based upon the science achievements, the research approaches and policy foundation for market trading about the wetland carbon sink had been analyzed for that sink sustainability. It was concluded that the decomposition reduction of wetland plant material and rewetting and suitable restoration of wetland are essential for its sink conservation. Nowadays, China has already set the wetland conservation for its carbon sink sustainability as a part of the national goal in the carbon peaking road-map, further elaboration on the policymaking should be taken for the wetland sink conclusive into the voluntary market and as an offset of the partly compulsory reduction of emission.

Characteristics of pore structure are crucial to oil exploration and development in shale reservoirs, but practical evaluation of shale pore structure remains a longstanding challenge. In this study, based on nuclear magnetic resonance transverse relaxation time (T2) spectra under water-saturated and irreducible conditions, total pore space and moveable fluid space were skillfully determined. Meanwhile, multifractal spectra were used to characterize T2 distributions of total pore space and movable fluid space. The results show characteristic parameters of high probability measure areas of multifractal spectra (multifractal parameters) have strong negative correlations with T2 geometric mean value, and average radii of pore and throat increase with a decrease in the multifractal parameters, indicating the shale reservoirs with low values of the multifractal parameters may have good pore structure. Moreover, clay mineral content has strong positive effects on the multifractal parameters. In contrast, (quartz+feldspar) mineral content negatively influences on the multifractal parameters. Finally, new accurate models for permeability estimation in core scale and well-logging scale of shales are both proposed based on the multifractal parameters, which are also applicable for the other reservoirs. Overall, this study is important and timely for evaluating pore structure and predicting permeability in shale reservoirs.

Background: Cervical lymph nodes metastases are one of the most significant prognostic factors in patients with laryngeal carcinoma, whether treatment by surgery or by radiotherapy. The current study retrospected the postoperative radiotherapy of locally advanced supraglottic and glottic laryngeal carcinoma (at a greater risk of lymph node metastasis) to determine the effect of radiotherapy excluding cervical level Ⅳ lymph nodes. Methods: Patients of supraglottic type and glottic type were irradiated with level Ⅳ from January 2012 to June 2013, without level Ⅳ from July 2013 to December 2014, according to physicians’ decision. Ninety-three patients were selective neck irradiation (SNI) of levels Ⅱ-Ⅳ (Group A) and 87 patients were SNI of levels Ⅱ and Ⅲ (Group B). The comparison between Group A and Group B was made with observation of clinical risk of recurrence and radiation complications, as well as overall survival (OS), progress-free survival (PFS) and regional nodal recurrence-free survival. Results: No remarkable difference was observed in the distribution of recurrence, levels of relapse, OS, PFS and regional nodal recurrence-free survival between the 2 groups (p > 0.05). Mean radiation dose at level Ⅳ, thyroid and cervical esophagus showed significant difference between the 2 therapeutic groups (p < 0.01). As regard radiation complications, no significant difference was found in radiation dermatitis of any grade between the 2 groups (p > 0.05). However, there was remarkable difference in clinical hypothyroidism and radiation esophagitis between Group A and Group B (p < 0.05). Conclusions: Radiotherapy after surgery omitting level Ⅳ may improve the quality of life in patients with locally advanced supraglottic and glottic laryngeal carcinoma, won’t worsen the prognosis as well.

Abstract Background Our study aimed to investigate the roles of autophagy against high glucose induced response in retinal pigment epithelium (ARPE-19 cells). Methods The morphological changes and reactive oxygen species (ROS) generation in ARPE-19 cells under high glucose treatment were respectively detected using the transmission electron microscopy and flow cytometry. The expression levels of Parkin, PINK1, BNIP3L, LC3-I and LC3-II in ARPE-19 cells received high glucose treatment were measured by western blot after pretreatment of carbonyl cyanide m-chlorophenylhydrazone (CCCP), 3-methyladenine (3-MA), N-acetyl cysteine (NAC) or cyclosporin A (CsA) followed by high glucose treatment. Results ARPE-19 cells subjected to high glucose stress showed an obvious reduction in the LC3-I expression and significant increase in the number of autophagosomes, in the intracellular ROS level, and in the expression levels of Parkin, PINK1, BNIP3L and LC3-II (p

Gelsemium elegans (Gardner & Champ.) Benth. (GE) has therapeutic effects for pain and malignant tumors but also has high toxicity. Its mechanism of toxicity has not yet been fully clarified, thus limiting its application. Meanwhile, evidence has shown that circRNAs are closely related to the progression of disease. However, very little is known about their expression profiles during intoxication. In this paper, circRNA/mRNA microarrays were respectively performed to detect their expression profiles in mice with acute GE intoxication versus normal controls. CircRNAs were verified by qRT-PCR in subsequent experiments. A regulation pattern of circRNA→miRNA→mRNA was deduced based on intersection analysis of circRNA/mRNA microarrays. The results revealed circRNAs (143) and mRNAs (1,921) were significantly expressed during intoxication. Most of the circRNAs were exonic, and most distributions in chromosomes were transcribed from chr1, chr2, chr7, and chr11. Furthermore, dysregulated expression of mmu-circRNA-013703 and mmu-circRNA-010022 was verified. Then a circRNA-targeted miRNA-mRNA co-expression network was constructed. The network map contained 2 circRNAs, 52 miRNAs, and 752 mRNAs. GO & KEGG analysis further predicted that mmu-circRNA-013703 and mmu-circRNA-010022 may participate in cellular survival/demise-related, neuron/synapse-related, and channel-related pathways. Based on functional modules analysis, a new network was formed, in which mmu-circRNA-013703 VS mmu-miR-361-3p linked to most mRNAs. Most of these mRNAs were known to be involved in the aforementioned functional module. This indicated that mmu-circRNA-013703 functioned as a sponge of miRNAs to regulate the more comprehensive circRNA-miRNA-mRNA co-expression network. Our approach revealed a landscape of dysregulated circRNA-miRNA-mRNA and may be valuable for the identification of new biomarkers during intoxication.

In the development of tight reservoirs, the permeability of the rock possesses strong stress sensitivity with the dynamic change of formation pressure and effective stress. To quantify the stress sensitivity of permeability in tight reservoirs and its impacts on the oil production, we carried out a systematic experimental study using core samples from both tight sandstone and limestone reservoirs in Sichuan Basin. In particular, the stress sensitivity of permeability for each type of rocks was examined at reservoir conditions by two methods: (a) constant pore pressure with variable confining pressure and (b) constant confining pressure with variable pore pressure. The results show that both tight sandstone and limestone reservoirs have strong stress sensitivity of permeability, while the stress sensitivity of permeability for sandstone reservoir is larger than limestone reservoir. In addition, it is found that the variable pore pressure method can better reflect the characteristics of the stress sensitivity of permeability during the development of tight reservoirs than variable confining pressure method. The stress sensitivity of permeability for tight sandstone can be attributed to the impacts of narrow throats, while the stress sensitivity of permeability for tight limestone is dominantly influenced by the micro- and nanoscale fractures. For tight reservoirs with high stress sensitivity, the producing pressure drop can be controlled by selecting a reasonable producing pressure drop to reduce the damage in permeability caused by the stress sensitivity.

Mg–2Y–0.6Nd–0.6Zr alloy was first deformed by equal channel angular pressing (ECAP), then rolled and deformed under ultralow temperature conditions (liquid nitrogen immersion), and finally annealed. Optical microscopy (OM), electron backscatter diffraction technology (EBSD), and transmission electron microscopy (TEM) were used to analyze the evolution of the multiscale microstructure and changes in the mechanical properties of the alloy under ultralow temperatures and various annealing conditions. The results showed that the alloy treated with ECAP obtained fine grains, and a large number of fine twins were formed during the ultralow-temperature rolling process, which promoted the improvement of its hardness and strength and provided numerous preferential nucleation sites. The annealing made it easier to induce recrystallization and improve the recrystallization nucleation rate. The twin boundary produced by the alloy after ultralow-temperature rolling and the uniform fine grains formed by annealing resulted in excellent strength and plasticity of the alloy. The twins formed after rolling under ultralow temperatures were mainly {101-2} <1-011> tensile twins. The alloy had comprehensive mechanical properties with a tensile strength of 186.15 MPa and an elongation of 29% after annealing at 350 °C for 10 min.

Traditional cancer treatment modalities such as surgery, chemotherapy, and radiation therapy have seen significant advancements in the past. However, inherent drawbacks, including systemic toxicity and high recurrence rates. Consequently, The nanoparticles, with their targeting and multifunctionality, have captured significant attention. This work synthesizes HMNPs-C60-N-GQDs-SS-PEI (HMNPs:Fe3O4@SiO2@mSiO2-C18) nanoparticles, integrating diverse functionalities for enhanced cancer therapy. The inclusion of SiO2 and C60 significantly improves the loading efficiency of gallic acid (GA). The magnetic properties of HMNPs enable efficient targeting to cancer sites under external magnetic fields. The -SS- linkage ensures drug release exclusively in tumor cells over-expressing glutathione (GSH), minimizing adverse effects on normal tissues. Introduction of Polyethyleneimine (PEI) imparts positive charge to facilitate accumulation on negatively charged tumor surfaces and enhances biocompatibility. Additionally, the fluorescence properties of N-doped graphene quantum dots (N-GQDs) facilitate real-time monitoring of material distribution in vivo during mouse and clinical therapy. Furthermore, the nano-magnetic targeting material demonstrates efficient drug loading and precise control over drug release, addressing issues such as the poor biocompatibility and high biotoxicity associated with traditional materials. This study not only achieves effective tumor treatment but also offers a promising direction for developing efficient multifunctional nano-targeting materials.

This study used quantitative methods to assess students' Chinese language learning attitudes and learning habits on Kahoot, a game-based learning platform. Kahoot enables teachers to transform bland Chinese vocabulary memorization into exciting, game-like situations. It makes Chinese language learning fun and interactive. The study aims to compare Kahoot team play mode with individual play mode. Sixty-four fifth graders participated. In the experimental group, students grouped by themselves or the teacher to compete with one another. They enjoyed working together to share what they knew and learned from each other. Students were tested prior to the course (pretest) and following the course (post-test). Observation notes, lesson plans, and surveys were also included. Analysis of the multiple types of data strengthens the conclusion that Kahoot can be an effective tool for teaching Chinese vocabulary, sentences, and culture. [ABSTRACT FROM AUTHOR]