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To quantitatively study the coupled dynamic behavior of vehicles in collision with semirigid guardrails, a coupled numerical model is established based on the finite element method. This model comprehensively integrates the nonlinear dynamic behavior of both the vehicle body and the guardrail structure. We validate the numerical results by comparing them with experimental findings and theoretical empirical formulas, confirming the accuracy of the coupled numerical model. This quantitative study investigates the influence of vehicle speed, column wall thickness, and collision angle on this coupled dynamic behavior to help optimize practical guardrail engineering designs. The results indicate that the sensitivity values of the collision speed, column wall thickness, and collision angle according to the baseline model are 1.0, 1.0, and 0.741, respectively. The parameters with higher sensitivity values are the key factors to consider in designs. Thus, the coupled numerical model can be used to optimize the design of semirigid guardrails in practical engineering. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have attracted increasing interest due to their excellent properties and various applications such as energy storage, sensors, composites and catalysis. Recently, 2D van der Waals (vdW) layered materials, MoSi2N4 and WSi2N4, have been synthesized successfully by CVD methods. Here, we have investigated the structure, optoelectronic properties and electron–hole excitation characteristics of two-dimensional MoSi2N4, MoSi2P4, and WSi2N4 using first-principles calculations to determine whether they can be applied for photocatalytic hydrolysis. The results showed that replacing N atoms in 2D MoSi2N4 with P atoms could not only reduce the bandgap, but also make the band position more negative, while replacing Mo atoms with W atoms could expand and move the bands towards more positive direction. H+ ions can obtain electrons to generate H2 from the conduction band of WSi2N4 where the conduction band minimum (CBM) and valence band maximum (VBM) is –0.43 and –2.49 eV, respectively. Time-dependent density functional theory is used to explain that the experimentally measured UV–Vis spectra in which visible light absorption is broader and more intense in WSi2N4 than in MoSi2N4 and WSi2N4 is a promising photocatalyst for H2 generation from water. [ABSTRACT FROM AUTHOR]

Four binuclear tridentate copper(I) complexes were synthesized based on the trans effect of the hybrid ligands. The catalytic performance and behavior of the prepared copper(I) complexes were evaluated in the carboxylative cyclization of propargylic amines with CO 2 . The combined use of copper(I) complexes and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) provided a catalytic system for the synthesis of a wide range of oxazolidinones from various propargylic amines and CO 2 under mild reaction conditions (room temperature-40 °C and 1 bar CO 2 ). The key factor for the success of the protocol is the use of copper complexes possessing the quality of hemilabile properties between N-heterocyclic carbenes and nitrogen donors. NMR measurements, density functional theory (DFT) calculations, and previous reports for the coordination behavior of the nickel complexes support the existence of the trans effect between N-heterocyclic carbenes and nitrogen donors.

Purpose: This phase II study was undertaken to determine the efficacy and safety of Loubo® (Lobaplatin) in combination with pemetrexed in treating patients with metastatic breast cancer who failed to respond to anthracycline or taxanes., Patients and Methods: Metastatic breast cancer cases who had previously received an anthracycline and a taxane in either adjuvant or metastatic settings, were enrolled. All patients were recruited from Jiangsu Cancer Hospital and Research Institute, and were treated with Loubo® (Lobaplatin) 35 mg/m2 (intravenous; on day 1) and pemetrexed 500 mg/m2 (intravenous; on day 1) every 21 days. Efficacy and side effects were evaluated after at least two cycles of chemotherapy., Results: All eligible 19 patients completed at least 2 cycles of chemotherapy with pemetrexed and lobaplatin, and were evaluable. Overall, 3 (15.8%) patients achieved partial response, 11 (57.9%) stable disease, 5 (26.3%) progression of disease, with no complete remission. Response rate was 15.8%, disease control rate was 42.1%. The median survival time was 10.3 months. Neutrophil suppression occurred in 36.8% of patients who had grade 2 toxicity, and 26.3% had grade 3, 26.4% had grade 4. Thrombocytopenia was encountered as follows: 21.1% grade 2, 15.8% grade 3 and 5.5% grade 4. Incidences of anemia were 10.5% in grade 2, 5.3% grade 3 and 0% grade 4. Only 5.3% of patients required packed red blood cell transfusion. Grade 3 digestive tract toxicity occurred in 5.5% of patients. Other toxicities included elevated transaminase, oral mucositis and skin rashes., Conclusions: The regimen of lobaplatin and pemetrexed is modestly active in metastatic breast cancer patients who failed anthracycline or taxanes, and the toxicity profile suggesting that the doses of chemotherapy should be further modified.