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Acceleration of objects in fluids widely exists in biological propulsions and contains rich unsteady fluid mechanisms. In this paper, the instantaneous drag force on accelerating normal flat plates (circular, elliptical, square, and rectangular plates) in a wide range of dimensionless acceleration ( a * = 1 6 ∼ 2) is measured, and the underlying mechanism for force generation is investigated. At first, we find that the drag force coefficient generally scales with the square root of a * when a * < 1.0 , coinciding with the scaling law given by Reijtenbagh et al. (PRL. 2023,130,174001). However, the drag force coefficient more linearly scales with a * rather than a * when a * > 1.0 , thereby indicating acceleration plays two distinct roles on the force generation depending on a * . Moreover, two scaling laws are built to quantitatively describe the two distinct roles of a * on the drag force generation. Based on fluid impulse, the drag force is largely contributed by the added mass of the accelerating plates (added mass force) and vorticity generation fed by the shear layer on the edge of the plates (vortex creation force). When a * < 1.0 , the vortex creation force scales with a * and almost contributes to the total drag force. When a * > 1.0 , the added mass force scaling with a * contributes to most of the drag force. Furthermore, the two force generation mechanisms associated with acceleration ( a * ) are independent, and a criterion based on the energy ratio is proposed to identify the transition of the two force generation mechanisms. The present results uncover the role of acceleration in force generation and explain the inconsistencies of using one quasi-steady model in describing the force on accelerating plates. [ABSTRACT FROM AUTHOR]

Background: This study explored the significance of consolidation maintenance chemotherapy after concurrent chemoradiotherapy with different regimens in patients with esophageal squamous cell carcinoma. Method: A prospective randomized controlled phase III clinical trial was designed and registered in the China Clinical Trials Registry (Registration number: ChiCTR‐TRC‐12002719). Survival data were analyzed in terms of intention‐to‐treat (ITT) and per‐protocol (PP) sets for patients undergoing cisplatin and 5‐fluorouracil (PF) (group A), or cisplatin and paclitaxel (TP) (group B). Results: The incidence risk of grade III–IV leukopenia in group B was higher than in group A (49.2% vs. 25.5%, p = 0.012). The survival rates at 1, 2, 3, and 5 years were 83.8%, 62.6%, 53.1%, and 41.3%, respectively. Consolidation chemotherapy after concurrent chemoradiation therapy had no benefit on median progression‐free survival (PFS) (p = 0.95) and overall survival (OS) (p = 0.809). According to the ITT analysis, the median PFS in group A and group B was 28.6 months and 30.3 months (X2 = 0.242, p = 0.623), while the median OS was 31.0 months and 50.3 months (X2 = 1.25，p = 0.263). For the PP analysis, the median PFS in group A and group B were 28.6 months and 30.3 months (p = 0.584), while the median OS was 31.0 months and 50.3 months (p = 0.259), respectively. Patients receiving consolidation chemotherapy did not show significant OS benefits (46.9 months vs. 38.3 months; X2 = 0.059, p = 0.866). Conclusion: Similar PFS and OS were found between PF and TP regimens with concurrent chemoradiotherapy. Consolidation chemotherapy did not show any significant OS benefits. [ABSTRACT FROM AUTHOR]

The genesis and primary compositions of carbonatite melts are enigmatic owing to their reactivity and resulting contamination in the mantle and crust. This overprints earlier uncontaminated compositions and obscures their origins. The subvolcanic Badou carbonatite in the North China Craton is characterized by brecciated textures and comprises pristine clinopyroxene, mica, and apatite phenocrysts in a mixed, carbonate–silicate matrix. Here, we provide mineralogical, textural, and major and trace elemental results to reveal the mantle derivation of the Badou carbonatite melt, and its compositional modification during interaction with crustal materials. Clinopyroxene and apatite phenocrysts have initial Sr isotopes (0.70920–0.71037) similar to brecciated calcite (0.71028–0.71159) and the whole rock (0.70953–0.71061), indicating a common source. Rare Mg-rich clinopyroxene and mica contain high Cr and Ni contents, recording direct mantle derivation without immiscibility from silicate melts. Abundant feldspars and aegirine, occurring as both phenocrysts and fine-grained matrix, formed an antiskarn at relatively low temperatures indicating extensive silica contamination upon crustal emplacement. Silica contamination is further indicated by britholite-rich apatite rims and relict quartz cores in clinopyroxene. Zircon xenocrysts were partly assimilated, indicated by Zr and Hf enrichment in late-stage silicates, and partly underwent decomposition to baddeleyite in a decreasing silica activity environment. The assimilation process consumed the carbonate melt, forming refractory silicate minerals and CO2 vapor, leading to near-surface gas overpressure with a decrease in magma viscosity. This elevates the potential for explosive activity, which, in turn, provides a positive feedback mechanism for silica assimilation. The complex evolution of the carbonatite melt in the crust might be responsible for the compositional gap between the natural rocks and experimental outcomes, and results in different eruption styles. [ABSTRACT FROM AUTHOR]

In this paper, we develop a multi-objective integrated optimization method for feeder buses of rail transit based on realistic considerations. We propose a bus stop selection method that considers the influence of shared motorcycles, which can score the importance of alternative bus stops and select those with the highest scores as objectives. The objective of the model in this paper is to minimize both the travel costs of passengers and the operating costs of the bus company. This is achieved by optimizing feeder bus routes, the frequency of departures, and interchange discounts to enhance the connectivity between feeder buses and rail transit. In addition, to ensure the feasibility of generated routes in the real road network, a genetic algorithm encoded with priority is used to solve this model. We use the Xingyao Road subway station in Kunming as an example, and the results show that the optimization method is effective. [ABSTRACT FROM AUTHOR]

Temperature-induced metal–insulator transition (MIT) in vanadium dioxide (VO2) has been under intense research interest for decades both theoretically and experimentally. Due to the complex nature of electron correlations, the underlying physics behind the MIT in VO2 has yet to be fully grasped. In this work, we utilize the fine resolution of the scattering-type scanning near-field optical microscope to investigate the MIT in an epitaxial VO2 thin film on the (100)R TiO2 substrate with mid-infrared light. Bidirectional tweed-like metal–insulator phase coexistence patterns are observed and understood under the Landau free energy paradigm. More interestingly, delayed metallic nucleation is observed near the surface cracks due to local strain relief. This research proposes ideas in investigating the temperature–pressure phase diagram and tuning the interplay between local strain and MIT in oxide thin films. [ABSTRACT FROM AUTHOR]