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The interaction between hydrodynamic nonpropagating solitons in a water tank has been investigated within the framework of Larraza & Putterman and Miles theory. It is shown that these solitons, similar to one-dimensional boats, never pass through each other and exchange places, and thus their interaction can be described in terms of two-body potential. The interaction potential for two solitons with opposite polarity and that for solitons with like polarity are found to be pure repulsive and anharmonic, respectively. Based on the results, it is explained well why two solitons of an opposite pair repel each other as a distance is reached. while that of a like pair can oscillate about each other. 相似文献
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Lingzhi Liang Xia Ren Junyi Xu Yurong Ma Yunlin Xue Tao Zhuang Guisen Zhang 《Molecules (Basel, Switzerland)》2022,27(8)
Olanzapine is a commonly used drug in the treatment of schizophrenia, but its clinical application has been restricted by metabolic-related side effects. In order to mitigate the weight gain side effects caused by olanzapine, other drugs with different targets were selected for combined use and evaluated in animal models of schizophrenia. SEP-363856 is a novel psychotropic agent which is under phase III clinical trials for schizophrenia treatment. The aim of the research was to evaluate whether co-administration of olanzapine and SEP-363856 exerts synergistic anti-schizophrenic effects in the apomorphine (APO)-induced climbing test, the MK-801-induced hyperactivity test, and the Morris water maze test, and therefore reduces the weight gain side effects induced by olanzapine. Through isobolographic analysis, the results showed a synergistic interaction in the climbing test; the experimental ED30 (3 mg/kg) was significantly smaller (p < 0.05) than the theoretical ED30 (5 mg/kg). Additionally, such potentiating effects appeared additive in the MK-801 challenge experiment. Co-treatment with an effective dose of olanzapine and a low dose of SEP-363856 reversed MK-801-induced cognitive impairment symptoms in mice. Moreover, combination treatment with olanzapine and SEP-363856 controls sustained weight gain in mice with chronic exposure to olanzapine. These results support further clinical trials to test the effectiveness of co-treatment of olanzapine and SEP-363856 for controlling symptoms and weight gain in patients with schizophrenia during antipsychotic treatments. 相似文献
216.
A nonlinear time-varying dynamic model for right-angle gear pair systems, considering both backlash and asymmetric mesh effects,
is formulated. The mesh parameters that are characteristically time-varying and asymmetric include mesh stiffness, directional
rotation radius and mesh damping. The period-one dynamic motions are obtained by solving the dimensionless equation of gear
motion using an enhanced multi-term harmonic balance method (HBM) with a modified discrete Fourier Transform process and the
numerical continuation method. The accuracy of the enhanced HBM solution is verified by comparison of its results to the more
computational intensive, direct numerical integration calculations. Also, the Floquet theory is applied to determine the stability
of the steady-state harmonic balance solutions. Finally, a set of parametric studies are performed to determine quantitatively
the effects of the variation and asymmetry in mesh stiffness and directional rotation radius on the gear dynamic responses. 相似文献
217.
Dr. Xiaocui Liu Myron Heinz Dr. Junyi Wang Leibo Tan Prof. Max C. Holthausen Prof. Qing Ye 《Angewandte Chemie (International ed. in English)》2023,62(51):e202312608
The reaction of benzoborirene with one equivalent of isocyanides leads to benzene-fused boretes bearing one imine function, while the reaction with two equivalents of isocyanide affords 2,3-dihydro-2,3-diiminoboroles with perfect regioselectivity. The isocyanide double insertion products represent a novel type of 1,2-diimine with a benzoborole backbone. The reduction chemistry of the benzoborole-supported 1,2-diimine was investigated. Single- and two-electron reduction allow for the isolation and full characterization of a radical anion and a dianion, respectively. In stark contrast to the ordinary boroles, which should turn aromatic by accepting two electrons, the antiaromatic character of the benzoborole backbone is highlighted upon reduction, thus presenting a rare example of antiaromatic borole dianion. Detailed quantum chemical calculations provide a rationale for the observed regioselectivity and the electronic structure of the reduced borole diimine species. 相似文献
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An efficient method for the construction of the tetrahydrofolate skeleton is described. Starting from pterin analogues and aromatic amines, 8-deaza-5,6,7,8-tetrahydroaminopterin derivatives and the heterocyclic benzoyl isosteres were synthesized via a novel aziridine intermediate. Following this method, the byproducts of carbon-nitrogen bond hydrogenolysis in traditional synthetic strategy can be completely avoided. 相似文献
220.
Tongchao Xia Yuqi Yang Le Li Yuting Tan Yuan Chen Shengyan Wang Liming Ye Xu Bao Junyi Yang 《Biomedical chromatography : BMC》2022,36(4):e5327
Trans-ferulic acid-4-β-glucoside (FAG) is a monomer extracted from Radix Aconiti Lateralis Preparata, which is a potential candidate for the prevention and treatment of cold injury. To determine the concentration of FAG in rats, it is essential to develop an ultra-performance liquid chromatography coupled with MS/MS method. Chromatographic separation was achieved by an Acquity UPLC BEH C18 column (2.1 × 50 mm, 1.7 μm). A Xevo triple quadrupole tandem mass spectrometer was used to quantitatively determine FAG in the negative-ion mode. The standard calibration curve was linear over the concentration range of 0.1–100 μg/mL and 0.0626–31.28 μg/g for rat plasma and liver tissue homogenate samples, respectively. The inter- and intra-batch precision (% relative standard deviation) of the assay was ≤8.29%, and accuracy (% relative error) ranged from −7.41 to 10.99%. The matrix effect was between 92.99 and 102.39%. The oral absolute bioavailability of FAG was obtained as 1.80%. The results of tissue distribution suggested that FAG spread rarely in the liver and brown adipose, which was not propitious to exert its ability to treat cold injury. In general, these studies were significant to provide necessary information for further study. 相似文献