| 1. |
- Khan, Farooq-Ahmad, et al.
(författare)
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Designing Functionally Substituted Pyridine-Carbohydrazides for Potent Antibacterial and Devouring Antifungal Effect on Multidrug Resistant (MDR) Strains
- 2023
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Ingår i: Molecules. - : MDPI. - 1431-5157 .- 1420-3049. ; 28:1
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Tidskriftsartikel (refereegranskat)abstract
- The emergence of multidrug-resistant (MDR) pathogens and the gradual depletion of available antibiotics have exacerbated the need for novel antimicrobial agents with minimal toxicity. Herein, we report functionally substituted pyridine carbohydrazide with remarkable antimicrobial effect on multi-drug resistant strains. In the series, compound 6 had potent activity against four MDR strains of Candida spp., with minimum inhibitory concentration (MIC) values being in the range of 16-24 mu g/mL and percentage inhibition up to 92.57%, which was exceptional when compared to broad-spectrum antifungal drug fluconazole (MIC = 20 mu g/mL, 81.88% inhibition). Substitution of the octyl chain in 6 with a shorter butyl chain resulted in a significant anti-bacterial effect of 4 against Pseudomonas aeruginosa (ATCC 27853), the MIC value being 2-fold superior to the standard combination of ampicillin/cloxacillin. Time-kill kinetics assays were used to discern the efficacy and pharmacodynamics of the potent compounds. Further, hemolysis tests confirmed that both compounds had better safety profiles than the standard drugs. Besides, molecular docking simulations were used to further explore their mode of interaction with target proteins. Overall results suggest that these compounds have the potential to become promising antimicrobial drugs against MDR strains.
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| 2. |
- Liu, Tang hong, et al.
(författare)
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Differences in aerodynamic effects when trains with different marshalling forms and lengths enter a tunnel
- 2019
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Ingår i: Tunnelling and Underground Space Technology. - : Elsevier BV. - 0886-7798. ; 84, s. 70-81
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Tidskriftsartikel (refereegranskat)abstract
- Unsteady Reynolds-averaged Navier-Stokes (URANS) simulations were performed to simulate trains with different marshalling forms and lengths entering a tunnel. Three models, including a short train, a double train and a long train, were used to analyse the influence of the train configuration on the pressure variations during a train's passage. The results of the numerical predictions were validated against existing experimental data, with which they showed good agreement. The differences in the maximum pressure peak distribution and the pressure fluctuations were analysed by means of Mach diagrams. The results show that the grouping length exerts a considerable influence on the amplitude of the pressure on the train body and that the influence of the grouping length on the pressure variation on the tunnel wall varies with the location in the tunnel. The tunnel space can be divided into three and four zones with regard to the influences on the maximum positive and negative pressure values, respectively. The different marshalling forms also influence the maximum peak values and local profiles of the pressure history curves, although this influence is much slighter than that of the train's grouping length.
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| 3. |
- Xia, Yutao, 1995, et al.
(författare)
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Aerodynamic influences of typical windbreak wall types on a high-speed train under crosswinds
- 2022
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Ingår i: Journal of Wind Engineering and Industrial Aerodynamics. - : Elsevier BV. - 0167-6105. ; 231
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Tidskriftsartikel (refereegranskat)abstract
- The effect of windbreak wall types on their windproof effects on trains has been systematically investigated by comparing the flow field around a high-speed train behind three typical windbreak walls. These three typical windbreak walls are widely used along the windy railway lines in China, which include the earth embankment–type windbreak wall (EW), the road cutting–type windbreak wall (RW), and the straight reinforced concrete–type windbreak wall (SW). We compared the time-averaged crosswind-induced flows and aerodynamic performances of high-speed trains behind these three windbreak walls with the same height using numerical simulations. The results revealed that the windbreak wall geometric shape effects on the aerodynamic load coefficients varied according to the type of aerodynamic load and carriage marshalling positions but barely varied with yaw angles. The total drag coefficients of the train in the EW and RW were approximately 50–60% of that in the SW under the two smaller yaw angles and were only 30–40% for the largest yaw angle. For the absolute value of the side force and rolling moments coefficients, the maximum values for the head and middle cars both appeared in the RW, and the corresponding minimum values were obtained in the SW. The maximum and minimum values for the tail car were obtained at the SW and EW, respectively. The maximum of the rolling moment coefficient among three carriages in the SW was approximately 45–60% of that in the EW and only 30–40% of that in the RW. The time-averaged train surface pressure coefficient and flow patterns were similar between the EW and RW, which showed apparent differences from those in the SW. The SW provided a strong blocking effect on the incoming windward airflow and avoided the direct impact on the train. Compared with the RW, the uplifting effect of the EW's windward slope on the incoming flow further reduced the crosswind effect on trains. In addition, the dominating frequency characteristics of the aerodynamic loads were significantly affected by windbreak wall types. These findings provide a systematic understanding of the time-averaged aerodynamics of trains behind these three typical windbreak walls.
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| 4. |
- Yaqoob, Sana, et al.
(författare)
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Synthesis of Highly Potent Anti-Inflammatory Compounds (ROS Inhibitors) from Isonicotinic Acid
- 2021
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Ingår i: Molecules. - : MDPI AG. - 1431-5157 .- 1420-3049. ; 26:5
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Tidskriftsartikel (refereegranskat)abstract
- In search of anti-inflammatory compounds, novel scaffolds containing isonicotinoyl motif were synthesized via an efficient strategy. The compounds were screened for their in vitro anti-inflammatory activity. Remarkably high activities were observed for isonicotinates 5-6 and 8a-8b. The compound 5 exhibits an exceptional IC50 value (1.42 +/- 0.1 mu g/mL) with 95.9% inhibition at 25 mu g/mL, which is eight folds better than the standard drug ibuprofen (11.2 +/- 1.9 mu g/mL). To gain an insight into the mode of action of anti-inflammatory compounds, molecular docking studies were also performed. Decisively, further development and fine tuning of these isonicotinates based scaffolds for the treatment of various aberrations is still a wide-open field of research.
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