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1.
Alamri  Sagr  Rajhi  Ali A.  Wu  Liang 《Structural chemistry》2022,33(3):671-677
Structural Chemistry - In order to evaluate the electrical response of boron nitride nanocones (BNNCs) to phenol gas, density functional theory (DFT) calculations are employed. The sensitivity and...  相似文献   
2.
Journal of Thermal Analysis and Calorimetry - In this article, the intra-uterine flow with small suspended particles under the impact of heat transfer is investigated. Intra-uterine fluid motion...  相似文献   
3.
This study was conducted to determine the potential interaction of aged garlic extract (AGE) with carvedilol (CAR), as well as to investigate the role of S-allyl-l-cysteine (SAC), an active constituent of AGE, in rats with isoproterenol (ISO)-induced myocardial dysfunction. At the end of three weeks of treatment with AGE (2 and 5 mL/kg) or SAC (13.1 and 32.76 mg/kg), either alone or along with CAR (10 mg/kg) in the respective groups of animals, ISO was administered subcutaneously to induce myocardial damage. Myocardial infarction (MI) diagnostic predictor enzymes, lactate dehydrogenase (LDH) and creatinine kinase (CK-MB), were measured in both serum and heart tissue homogenates (HTH). Superoxide dismutase (SOD), catalase, and thiobarbituric acid reactive species (TBARS) were estimated in HTH. When compared with other groups, the combined therapy of high doses of AGE and SAC given alone or together with CAR caused a significant decrease in serum LDH and CK-MB activities. Further, significant rise in the LDH and CK-MB activities in HTH was noticed in the combined groups of AGE and SAC with CAR. It was also observed that both doses of AGE and SAC significantly increased endogenous antioxidants in HTH. Furthermore, histopathological observations corroborated the biochemical findings. The cytoprotective potential of SAC and AGE were dose-dependent, and SAC was more potent than AGE. The protection offered by aged garlic may be attributed to SAC. Overall, the results indicated that a high dose of AGE and its constituent SAC, when combined with carvedilol, has a synergistic effect in preventing morphological and physiological changes in the myocardium during ISO-induced myocardial damage.  相似文献   
4.
The density functional calculation is performed for centrosymmetric(La–Pm) GaO_3 rare earth gallates, using a full potential linear augmented plane wave method with the LSDA and LSDA+U exchange correlation to treat highly correlated electrons due to the very localized 4f orbitals of rare earth elements, and explore the influence of U = 0.478 Ry on the magnetic phase stability and the densities of states. LSDA+U calculation shows that the ferromagnetic(FM) state of RGaO_3 is energetically more favorable than the anti-ferromagnetic(AFM) one, except for LaGaO_3 where the NM state is the lowest in energy. The energy band gaps of RGaO_3 are found to be in the range of 3.8–4.0 eV, indicating the semiconductor character with a large gap.  相似文献   
5.
Ajuga bracteosa Wall. ex Benth. is an endangered medicinal herb traditionally used against different ailments. The present study aimed to create new insight into the fundamental mechanisms of genetic transformation and the biological activities of this plant. We transformed the A. bracteosa plant with rol genes of Agrobacterium rhizogenes and raised the regenerants from the hairy roots. These transgenic regenerants were screened for in vitro antioxidant activities, a range of in vivo assays, elemental analysis, polyphenol content, and different phytochemicals found through HPLC. Among 18 polyphenolic standards, kaempferol was most abundant in all transgenic lines. Furthermore, transgenic line 3 (ABRL3) showed maximum phenolics and flavonoids content among all tested plant extracts. ABRL3 also demonstrated the highest total antioxidant capacity (8.16 ± 1 μg AAE/mg), total reducing power, (6.60 ± 1.17 μg AAE/mg), DPPH activity (IC50 = 59.5 ± 0.8 μg/mL), hydroxyl ion scavenging (IC50 = 122.5 ± 0.90 μg/mL), and iron-chelating power (IC50 = 154.8 ± 2 μg/mL). Moreover, transformed plant extracts produced significant analgesic, anti-inflammatory, anticoagulant, and antidepressant activities in BALB/c mice models. In conclusion, transgenic regenerants of A. bracteosa pose better antioxidant and pharmacological properties under the effect of rol genes as compared to wild-type plants.  相似文献   
6.
Differential scanning calorimetry (DSC) studies were performed under nonisothermal conditions at various heating rates for glassy Se made by high-energy ball milling. Comparisons were made between the ball-milling technique and the melt-quenching and thin-film techniques. Well-defined endothermic and exothermic peaks were observed at the glass-transition temperature, Tg, and the onset temperature of crystallisation, Tc. The isoconversional method of Vyazovkin was used to determine the variation in the activation energy for crystallisation with temperature, Eα(T). The value of Eα(T) was dependent on the sample preparation method. The thermal stability of the Se glasses was evaluated by calculation of the temperature difference (Tc ? Tg) and the S-parameter. In addition, the glass-forming ability was estimated by the criteria of reduced glass-transition temperature, Trg, and the Hruby number, HR. The structures of the Se samples that resulted from the DSC analysis were identified using an X-ray diffractometer. The glasses formed using the thin film technique were the most stable.  相似文献   
7.
The aim of this research is to analyze the effects of mass transfer on second grade fluid flow subjected to the heat transfer incorporated with the relaxation time to reach the state of equilibrium on or after the state of upheaval. A new heat model namely Cattaneo–Christov heat flux comprising the relaxation time is employed instead of very commonly used mundane model based on classical theory of heat flux. Flow is considered towards stretching cylinder in the existence of external magnetic field. Suitable transformations are first used to deduce the momentum, heat and concentration equations and are then solved analytically. The effects of physical quantities such as fluid parameter, magnetic field, Schmidt number, relaxation time, curvature parameter, Prandtl number and chemical reaction on momentum, temperature and concentration profile are examined graphically whereas for validation of results convergence analysis along with residual error are obtained numerically. A comparison of obtained results is also given with the existing literature as a limiting case of reported problem and are found an excellent agreement. The temperature profile indicates thinning effect for higher values of Prandtl number and relaxation time. It is also noted that the velocity increases with increasing values of fluid parameter whereas it declines for the case of magnetic field. This study can be used an application of central heating system and to measure the fast chemical reactions rates.  相似文献   
8.
A new, highly selective, simple and accurate method was adopted and validated for the direct quantification of ibandronate sodium monohydrate (IBN) in tablets using sensitive polyvinyl chloride membrane electrodes. Three membranes were fabricated using dibutyl sebacate, nitrophenyl octyl ether and dioctyl phthalate. The fabricated electrodes showed fast response, capability of application in wide pH range and direct determination of IBN in turbid solutions. The most important advantage of the proposed analytical method is that it successfully allows direct determination of IBN in dosage form. The proposed analytical methodology can be applied for the direct quantification of IBN in pharmaceutical formulations.  相似文献   
9.
Herein, we report the synthesis of eight new mononuclear and binuclear Co2+, Ni2+, Cu2+, and Zn2+ methoxy thiosemicarbazone (MTSC) complexes aiming at obtaining thiosemicarbazone complex with potent biological activity. The structure of the MTSC ligand and its metal complexes was fully characterized by elemental analysis, spectroscopic techniques (NMR, FTIR, UV-Vis), molar conductivity, thermogravimetric analysis (TG), and thermal differential analysis (DrTGA). The spectral and analytical data revealed that the obtained thiosemicarbazone-metal complexes have octahedral geometry around the metal center, except for the Zn2+-thiosemicarbazone complexes, which showed a tetrahedral geometry. The antibacterial and antifungal activities of the MTSC ligand and its (Co2+, Ni2+, Cu2+, and Zn2+) metal complexes were also investigated. Interestingly, the antibacterial activity of MTSC- metal complexes against examined bacteria was higher than that of the MTSC alone, which indicates that metal complexation improved the antibacterial activity of the parent ligand. Among different metal complexes, the MTSC- mono- and binuclear Cu2+ complexes showed significant antibacterial activity against Bacillus subtilis and Proteus vulgaris, better than that of the standard gentamycin drug. The in silico molecular docking study has revealed that the MTSC ligand could be a potential inhibitor for the oxidoreductase protein.  相似文献   
10.
A new series of 8-methoxy-2-trimethoxyphenyl-3-substituted quinazoline-4(3)-one compounds were designed, synthesized, and screened for antitumor activity against three cell lines, namely, Hela, A549, and MDA compared to docetaxel as reference drug. The molecular docking was performed using Autodock Vina program and 20 ns molecular dynamics (MD) simulation was performed using GROMACS 2018.1 software. Compound 6 was the most potent antitumor of the new synthesized compounds and was evaluated as a VEGFR2 and EGFR inhibitor with (IC50, 98.1 and 106 nM respectively) compared to docetaxel (IC50, 89.3 and 56.1 nM respectively). Compounds 2, 6, 10, and 8 showed strong cytotoxic activities against the Hela cell line with IC50 of, 2.13, 2.8, 3.98, and 4.94 µM, respectively, relative to docetaxel (IC50, 9.65 µM). Compound 11 showed strong cytotoxic activity against A549 cell line (IC50, 4.03 µM) relative to docetaxel (IC50, 10.8 µM). Whereas compounds 6 and 9 showed strong cytotoxic activity against MDA cell line (IC50, 0.79, 3.42 µM, respectively) as compared to docetaxel (IC50, 3.98 µM).  相似文献   
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