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This study examined the impact of Core Stability Training (CST) on the jump serve speed of elite male volleyball athletes. A total of 20 athletes participated in a 10-week in-tervention, with participants assigned to either the Core Stability Training Group or the Conventional Core Strength Training Group. Core stability metrics, Jump serve arm-swing performance, and jump serve speed were assessed via pre-test, mid-test, and post-test measurements. Results indicated that all measured indicators showed significant improvements in both groups ( P  < 0.05). However, the Core Stability Training Group demonstrated significantly greater enhancements in side plank endurance, 1-minute sit-up performance, plank hold duration, and Jump serve arm-swing performance (assessed via medicine ball forward throw and badminton long throw) compared to the Conventional Group. Post-test data revealed that the jump serve speed of the Core Stability Training Group was significantly higher than that of the control group ( P  = 0.037). Correlation analysis confirmed positive associations between core stability, Jump serve arm-swing performance, and serve speed. The findings suggest that Core Stability Training effectively enhances the jump serve speed of male volleyball athletes. The un-derlying mechanism involves improvements in core stability and the efficiency of force transfer along the kinetic chain, which in turn increases the swing speed of the distal limbs.

To date, researchers have not systematically investigated the geological characteristics of deep shale gas reservoirs in the Western Chongqing Block. Furthermore, the single technique remains insufficient for characterizing the complexity of their multi-scale pore structures. Therefore, this study integrates scanning electron microscopy (SEM), argon ion polishing-field emission scanning electron microscopy (AIP-FESEM), high-pressure mercury intrusion (HPMI), and low-pressure gas adsorption (LPGA) to qualitatively and quantitatively investigate the microscopic pore structure of shale gas reservoirs in the Western Chongqing block. Meanwhile, the pore fractal characteristics were analyzed based on HPMI and LPGA experiments using the mercury saturation model, the Frenkel-Halsey-Hill (FHH) model, and the volume-surface area (V-S) model. The results show that, first, the pore types of the samples in the Western Chongqing block include organic pores, intergranular pores, intragranular pores, intercrystalline pores, and interlayer fractures; second, micropores are the main contributors to the total pore volume, mainly developed in the three ranges of 0.45 ~ 0.5 nm, 0.55 ~ 0.6 nm, and 0.8 ~ 0.85 nm, followed by mesopores and finally macropores; finally, the macropores of the samples exhibit stronger heterogeneity and more complex pore-throat structures compared to mesopores. The heterogeneity of the pore structure is stronger than that of the pore surface, indicating a more complex internal pore structure. Additionally, the microporous structures of the samples are also characterized by relatively complex. The experimental results provide important guidance for the economical and efficient development of shale gas.

As a clean energy source, shale gas plays a vital role in supporting China’s strategic objectives of carbon peaking and carbon neutrality through its efficient development. Due to the low porosity, low permeability, complex pore structure, and strong heterogeneity of deep shale gas reservoirs, the gas-water two-phase seepage law and flow characteristics remain unclear. This study focuses on deep shale gas in the Western Chongqing block as the research subject. Through the gas-water displacement experiments combined with NMR techniques, the gas-water two-phase seepage laws and flow characteristics of the shale gas matrix-fracture system were revealed. The results show that: (1) In the water displacement gas experiment, formation water cannot break through the matrix-type sample, with its displacement velocity decreasing over time and eventually approaching zero. Under the same time conditions, the higher the displacement pressure, the faster the displacement velocity, and the higher the NMR signal. The matrix-fracture type sample breaks through in a short time, and the time when the NMR signal is stable is much less than that of the matrix-type sample. The displacement pressure is negatively correlated with the NMR signal. (2) In the reverse gas displacement experiment, the gas cannot break through the matrix-type sample. For the matrix-fracture type sample, as the displacement pressure increases, the water phase relative permeability increases, the irreducible water saturation decreases, the gas phase relative permeability decreases, the co-permeability zone slightly expands, and the equal permeability point shifts to the lower left. The findings provide a theoretical basis for the efficient development of shale gas in China.

MicroRNAs have been reported to play critical roles in the regulation of non‐small‐cell cancer (NSCLC) development, but the role of microRNA (miR)‐331‐3p in NSCLC is still unclear. In this study, the expression levels of miR‐331‐3p in NSCLC tumor tissues and adjacent normal tissues were examined by quantitative RT‐PCR, and the relationship between miR‐331‐3p expression and patient clinicopathological characteristics was analyzed. The effects of miR‐331‐3p on epithelial‐mesenchymal transition (EMT), migration, and metastasis of NSCLC cells were determined in vitro and vivo. Direct functional targets of miR‐331‐3p were identified by luciferase reporter assay, western blot assay, immunohistochemical staining, and rescue assay. The downstream pathway regulated by miR‐331‐3p was identified by immunofluorescence, immunoprecipitation, and Rac1 activity examination. Our results showed that miR‐331‐3p was significantly downregulated in NSCLC tumor tissues and was correlated with clinicopathological characteristics, and miR‐331‐3p could be an independent prognostic marker for NSCLC patients. Furthermore, miR‐331‐3p significantly suppressed EMT, migration and metastasis of NSCLC cells in vitro and in vivo. Both ErbB2 and VAV2 were direct functional targets of miR‐331‐3p. The activities of Rac1, PAK1, and β‐catenin were regulated by miR‐331‐3p through ErbB2 and VAV2 targeting. These results indicated that miR‐331‐3p suppresses EMT, migratory capacity, and metastatic ability by targeting ErbB2 and VAV2 through the Rac1/PAK1/β‐catenin axis in NSCLC. Our results showed that microRNA (miR)‐331‐3p was significantly downregulated in non‐small‐cell cancer (NSCLC) tumor tissues and was correlated with clinicopathological characteristics, and miR‐331‐3p could be an independent prognostic marker for NSCLC patients. Furthermore, miR‐331‐3p significantly suppressed EMT migration and metastasis of NSCLC cells in vitro and in vivo. Both ErbB2 and VAV2 were direct functional targets of miR‐331‐3p. The activities of Rac1, PAK1, and β‐catenin were regulated by miR‐331‐3p through ErbB2 and VAV2 targeting. These results indicated that miR‐331‐3p suppresses EMT, migratory capacity, and metastatic ability by targeting ErbB2 and VAV2 through the Rac1/PAK1/β‐catenin axis in NSCLC.

For shale gas development, it is essential to clarify the main controlling factors of EUR and realize its accurate prediction. Based on data from 123 wells in the Weiyuan block, this study combines Pearson correlation analysis, RF-RFE algorithm, and Boruta algorithm to screen out the main controlling factors of EUR. The GBDT, RF, SVR, MLP, and ERT algorithms optimized by the Optuna framework are then used to build EUR prediction models, and the optimal model is further interpreted using SHAP. The results show that: (1) Five main controlling factors are selected: drilled length of type I reservoir, thickness of the L1 1 1 sub-member, fracturing fluid volume, vertical depth, and 360-day flowback rate. (2) Optuna-GBDT outperforms other models on both the training and test sets, with an R 2 of 0.8214 on the test set, demonstrating high prediction accuracy. (3) The global feature importance ranking based on the mean absolute SHAP values of each feature is as follows: thickness of the L1 1 1 sub-member > drilled length of type I reservoir > 360-day flowback rate > fracturing fluid volume > vertical depth. The first four features contribute positively to the model output to different degrees, while vertical depth has a more complex effect on the model in this study, not showing a simple positive or negative trend. The Optuna-GBDT model, combined with SHAP-based interpretation, provides a practical and efficient idea for EUR prediction in shale gas wells.

The primary horizontal well network in the Weiyuan block is vertically deployed in the Long1 1 1 sub-layer, and it is difficult to fully utilize the 43.9–53.6 m thick Wufeng formation-Long1 1 sub-member. To enhance the reserves utilization degree, this study proposes a method for evaluating the vertical utilized degree of shale gas reserves based on the calibrated estimated ultimate recovery (EUR) iterative utilized thickness and a quantitative evaluation method of shale gas reservoir productivity based on reservoir classification. The reserves utilization degree and vertical utilization thickness of the primary well network in the Weiyuan block are evaluated, the distribution characteristics of remaining reserves are clarified, and the three-dimensional development potential is analyzed. The results show that: (1) The horizontal well hydraulic fracture network of the primary well network in the production area mainly utilized the Wufeng formation-Long1 1 3 sub-layer, and the utilized thickness is between 3.49 and 19.40 m, with an average of 13.79 m. Vertically, only 30% of the reservoir is utilized. (2) The well-control reserve recovery of the primary well network in the production area is 75%, the average EUR of half-branch wells is 0.87 × 10 8 m 3 , the average well-control geological reserves of half-branch wells are 1.16 × 10 8 m 3 , and the total well-controlled geological reserves in the whole area are 906.7 × 10 8 m 3 . (3) The total remaining geological reserves are 1690.5 × 10 8 m 3 , the average remaining reserves abundance is 4.31 × 10 8 m 3 /km 2 , the average thickness of unutilized reserves is 26.16 m, and the high-value areas are all located in the eastern part of the production area. (4) Under the condition of the same thickness, the ratio of gas production capacity of Type I and Type II reservoirs is 3.7:1. (5) According to the favorable area screening principle, the favorable area is screened out to be 116.7 km 2 , and the total geological reserves are 700.7 × 10 8 m 3 . This study provides a new development idea for improving shale gas production in the Weiyuan block.

The development of water drive gas reservoirs (WDGRs) with fractures or strong heterogeneity is severely influenced by water invasion. Accurately simulating the rules of water invasion and drainage gas recovery countermeasures in fractured WDGRs, thereby revealing the mechanism of water invasion and an appropriate development strategy, is important for formulating water management measures and enhancing the recovery of gas reservoirs. In this work, physical simulation methods were proposed to gain a better understanding of water invasion and to optimize the water control of fractured WDGRs. Five groups of experiments were designed and conducted to probe the impacts of the distance between the fractures and the gas well, the drainage position, the drainage timing and the aquifer size on the water invasion and production performance of a gas reservoir. The gas and water production and the internal pressure drop were monitored in real time during the experiments. Based on the above experimental works, a theoretical analysis was conducted to quantitatively evaluate the performance of the gas reservoir recovery via the gas well production performance, water invasion, dynamic pressure drop and residual gas and water distribution analysis. The results show that when the fracture scale was appropriate, a gas well drilled close to a fracture (Experiment 1-3) or a high-permeability formation could also produce gas and achieve drainage efficiently. The recovery factor of Experiment 1-3 reached 62.5%, which was 24.6% and 21.1% higher than those of Experiments 1-1 and 1-2, respectively, which had wells drilled in low-permeability areas. Draining water near an aquifer can effectively inhibit water invasion during the early stage of gas recovery. The setup in Experiment 2-1 effectively inhibited water invasion and avoided the formation of water-sealed volumes of gas to recover 30% more gas than recovered with that of Experiment 1-1 without drainage wells. A shorter distance between the drainage well and the aquifer increased the drainage capacity and decreased the gas production capacity, respectively (Well 2 at Point A vs Point B). A larger aquifer had a lower gas recovery, which reduced the economic benefit. For example, due to an infinitely large aquifer, the reserves in Experiment 4-1 were developed by a single well, the gas recovery was only 33.4%. These research results are expected to be beneficial for the preparation of development plans and the optimization of water control measures for WDGRs.

Inflammation has long been accepted as a key component of carcinogenesis. During inflammation, inflammasomes are potent contributors to the activation of inflammatory cytokines that lead to an inflammatory cascade. Considering the contributing role of inflammasomes in cancer progression, inflammasome inhibitors seem to have a promising future in cancer treatment and prevention. Here, we summarize the structures and signaling pathways of inflammasomes and detail some inflammasome inhibitors used to treat various forms of cancer, which we expect to be used in novel anticancer approaches. However, the practical application of inflammasome inhibitors is limited in regard to specific types of cancer, and the associated clinical trials have not yet been completed. Therefore, additional studies are required to explore more innovative and effective medicines for future clinical treatment of cancer.

For fractured gas reservoirs with strong water drive, gas phase trapping affects the gas recovery significantly. The recovery may be less than 50% for some reservoirs while it is only 12% for Beaver River gas field. The gas phase trapping mechanism has been revealed by the results of depletion experimental test. The residual pressure of the trapped gas is as high as 11.75 MPa with a 12.8 cm imbibition layer resulting in gas recovery deceased 49.5% compared with that without imbibition layer. A mathematical model is built to calculate the imbibition thickness based on capillary pressure and relative permeability of the matrix. The gas phase trapping are analyzed by two representative wells in Weiyuan gas field, the intermittent production reinforces the imbibition thickness and result in gas trapped in the matrix block with high residual pressure for the low performace gas wells, the extremely low gas recovery can be explained more rationally. That lays a foundation of improving the gas recovery for fractured reservoirs.

Low-permeability to ultralow-permeability reservoirs of the China National Petroleum Corporation are crucial to increase the reserve volumes and the production of crude oil in the present and future times. This study aimed to address the two major technical bottlenecks faced by the low-permeability to ultralow-permeability reservoirs by a comprehensive use of technologies and methods such as rate-controlled mercury injection, nuclear magnetic resonance, conventional logging, physical simulation, numerical simulation, and field practices. The reservoir characteristics of low-permeability to ultralow-permeability reservoirs were first analyzed. The water flooding development adjustment mode in the middle and high water-cut stages for the low-permeability to ultralow-permeability reservoirs, where water is injected along the fracture zone and lateral displacement were established. The formation mechanism and distribution principles of dynamic fractures, residual oil description, and expanding sweep volume were studied. The development mode for Type II ultralow-permeability reservoirs with a combination of horizontal well and volume fracturing was determined; this led to a significant improvement in the initial stages of single-well production. The volume fracturing core theory and optimization design, horizontal well trajectory optimization adjustment, horizontal well injection-production well pattern optimization, and horizontal well staged fracturing suitable for reservoirs with different characteristics were developed. This understanding of the reservoir characteristics and the breakthrough of key technologies for effective development will substantially support the oil-gas valent weight of the Changqing Oilfield to exceed 50 million tons per year, the stable production of the Daqing Oilfield with 40 million tons per year (oil-gas valent weight), and the realization of 20 million tons per year (oil-gas valent weight) in the Xinjiang Oilfield.