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排序方式: 共有1225条查询结果,搜索用时 12 毫秒
991.
Dr. Bui Thi Buu Hue Phuong Hong Nguyen Dr. Tran Quang De Mai Van Hieu Eunji Jo Nguyen Van Tuan Than Thi Thoa Le Duc Anh Nguyen Hoang Son Danh La Duc Thanh Dr. Myrielle Dupont-Rouzeyrol Dr. Regis Grailhe Dr. Marc P. Windisch 《ChemMedChem》2020,15(15):1453-1463
We have synthesized 50 benzimidazole (BMZ) derivatives with 1,2-phenylenediamines and aromatic aldehydes under mild oxidation conditions by using inexpensive, nontoxic inorganic salt sodium metabisulfite in a one-pot condensation reaction and screened their ability to interfere with Zika virus (ZIKV) infection utilizing a cell-based phenotypic assay. Seven BMZs inhibited an African ZIKV strain with a selectivity index (SI=CC50/EC50) of 9–37. Structure-activity relationship analysis demonstrated that substitution at the C-2, N-1, and C-5 positions of the BMZ ring were important for anti-ZIKV activity. The hybrid structure of BMZ and naphthalene rings was a structural feature responsible for the high anti-ZIKV activity. Importantly, BMZs inhibited ZIKV in human neural stem cells, a physiologically relevant system considering the severe congenital anomalies, like microcephaly, caused by ZIKV infection. Compound 39 displayed the highest antiviral efficacy against the African ZIKV strain in Huh-7 (SI>37) and neural stem cells (SI=12). Compound 35 possessed the highest activity in Vero cells (SI=115). Together, our data indicate that BMZs derivatives have to be considered for the development of ZIKV therapeutic interventions. 相似文献
992.
Carla E. Garcia Pham Viet Tuan Mario R. Camana 《International Journal of Electronics》2020,107(10):1704-1733
ABSTRACT This paper investigates the solution to an optimisation problem to minimise the total transmission power at the transmitter in a cooperative non-orthogonal multiple access (NOMA) system with simultaneous wireless information and power transfer (SWIPT) and an energy-harvesting user. First, we formulate the optimisation problem to obtain the minimum transmission power at the transmitter under the constraints of minimum signal-to-interference-plus-noise ratio and minimum energy harvesting. Since the problem is not convex, we transform it into a bi-level optimisation problem. Then, conditions to guarantee the feasibility of the problem are provided, and we derive the analytical optimal solution via the Lagrange method meeting Karush–Kuhn–Tucker optimality conditions to solve the lower-level variables of the inner convex problem. Second, we use particle swarm optimisation to find the approximately optimal values of the upper-level variables. Next, we present two baseline schemes based on orthogonal multiple access (OMA) and equal power splitting for performance comparison with the proposed cooperative NOMA system with SWIPT. Finally, simulation results show that cooperative NOMA with SWIPT can reduce the transmit power at the transmitter, compared to two baseline schemes: OMA and EPS. 相似文献
993.
Rate effects on residual strength play an important role in predicting and evaluating the behaviour of reactivated landslides and in the application of test results and procedures. Although the rate dependency of residual strength has been investigated extensively, there is a lack of consistency in the experimental results. In particular, the effect of the shear rate on the residual strength of high-plasticity, low-permeability soils is not well understood. Additionally, field observations suggest that the sliding velocity of a soil block in the residual state is not constant and that its acceleration may affect the residual strength of the soil. However, the effect of acceleration changes on the residual strength of soil has not yet been investigated. The main objectives of this study are to elucidate the rate dependency of the residual strength of high-plasticity soils and investigate the effect of acceleration. In addition, the effect of the test procedure on the rate effect is also examined. A number of kaolin and kaolin–bentonite samples were tested using the Bishop-type ring shear device. The single-stage procedure which the shear rate was not changed during shearing, was conducted on individual specimens with shear rates from 0.02 to 20?mm/min to investigate the rate effect. The accelerations of 0.028 and 0.014?mm/min2 were applied in multi-stage procedure with shear rates increasing gradually from 0.002 to 20?mm/min to examine the acceleration effect. The test results show that the bentonite content significantly affects the rate effect on the residual strength of kaolin–bentonite mixtures. For instance, in the single-stage procedure, the presence of just 10% bentonite changes the rate effect from positive to negative. This may be due to the generation of unknown excess pore water pressure under fast shearing. Furthermore, the test results also show that the type of rate effect observed depends on the test procedure. For mixture samples of 90% kaolin and 10% bentonite, the rate effect is negative in the single-stage procedure but positive in the multi-stage procedure. The analysis of the experimental results suggests that the effect of acceleration can be neglected in determining the residual strength. 相似文献
994.
Quang-Huy Duong Philippe Fournier-Viger Heri Ramampiaro Kjetil Nørvåg Thu-Lan Dam 《Applied Intelligence》2018,48(7):1859-1877
Discovering high utility itemsets in transaction databases is a key task for studying the behavior of customers. It consists of finding groups of items bought together that yield a high profit. Several algorithms have been proposed to mine high utility itemsets using various approaches and more or less complex data structures. Among existing algorithms, one-phase algorithms employing the utility-list structure have shown to be the most efficient. In recent years, the simplicity of the utility-list structure has led to the development of numerous utility-list based algorithms for various tasks related to utility mining. However, a major limitation of utility-list based algorithms is that creating and maintaining utility-lists are time consuming and can consume a huge amount of memory. The reasons are that numerous utility lists are built and that the utility-list intersection/join operation to construct a utility-list is costly. This paper addresses this issue by proposing an improved utility-list structure called utility-list buffer to reduce the memory consumption and speed up the join operation. This structure is integrated into a novel algorithm named ULB-Miner (Utility-List Buffer for high utility itemset Miner), which introduces several new ideas to more efficiently discover high utility itemsets. ULB-Miner uses the designed utility-list buffer structure to efficiently store and retrieve utility-lists, and reuse memory during the mining process. Moreover, the paper also introduces a linear time method for constructing utility-list segments in a utility-list buffer. An extensive experimental study on various datasets shows that the proposed algorithm relying on the novel utility-list buffer structure is highly efficient in terms of both execution time and memory consumption. The ULB-Miner algorithm is up to 10 times faster than the FHM and HUI-Miner algorithms and consumes up to 6 times less memory. Moreover, it performs well on both dense and sparse datasets. 相似文献
995.
Anh Pham Vo Tuan Bao Vo Nguyen Quoc Le Khoa N. 《Wireless Personal Communications》2018,103(2):1859-1870
Wireless Personal Communications - This Letter studies performance of a dual-hop decode-and-forward relaying network employing a wireless-powered relay antenna with transmit antenna selection for... 相似文献
996.
Thang Vu Toan Tuan Nguyen Anh Tiep Nguyen Viet 《Journal of Mechanical Science and Technology》2018,32(3):1297-1305
Journal of Mechanical Science and Technology - Wear is one of the most influential factors in profile grinding. The measuring of grinding wheel wear is costly and time consuming. We introduce a new... 相似文献
997.
Anh Tuan Hoang Xuan Lam Bui Xuan Duong Pham 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(8):929-939
Not only marine species, but human and nature environment have been also affected seriously as the marine environment is polluted by oil spill, heavy metal, and others. In this study, a new sorbent fabricated by adding rice straw into polyurethane foams was investigated. Oil types such as crude oil, fuel oil, diesel oil, kerosene and a solution containing Cd2+, Cu2+ metal ion were used to evaluate the absorption capacity of this new sorbent. The experimental result after 150 minutes showed that, the oil absorption capacity of new sorbent added 25% of rice straw mass and 500 μm of size was highest, correspondingly to 15.086 g/g, 13.964 g/g, 12.226 g/g, 10.746 g/g of crude oil, fuel oil, diesel oil, kerosene, respectively. Moreover, Cd2+, Cu2+ metal ion absorption capacity was 212.9 mg/l and 193.6 mg/l. Besides, the relationship between contact angles and pore diameters, oil absorption capacity and oil surface tension, SEM were considered. 相似文献
998.
Md Arafat Mahmud Huyen T. Pham The Duong Yanting Yin Jun Peng Yiliang Wu Wensheng Liang Li Li Anand Kumar Heping Shen Daniel Walter Hieu T. Nguyen Naeimeh Mozaffari Grace Dansoa Tabi Gunther Andersson Kylie R. Catchpole Klaus J. Weber Thomas P. White 《Advanced functional materials》2021,31(46):2104251
Dimensional engineering of perovskite films is a promising pathway to improve the efficiency and stability of perovskite solar cells (PSCs). In this context, surface or bulk passivation of defects in 3D perovskite film by careful introduction of 2D perovskite plays a key role. Here the authors demonstrate a 2D perovskite passivation scheme based on octylammonium chloride, and show that it provides both bulk and surface passivation of 1.6 eV bandgap 3D perovskite film for highly efficient (≈23.62%) PSCs with open-circuit voltages up to 1.24 V. Surface and depth-resolved microscopy and spectroscopy analysis reveal that the Cl− anion diffuses into the perovskite bulk, passivating defects, while the octylammonium ligands provide effective, localized surface passivation. The authors find that the Cl− diffusion into the perovskite lattice is independent of the 2D perovskite crystallization process and occurs rapidly during deposition of the 2D precursor solution. The annealing-induced evaporation of Cl from bulk perovskite is also inhibited in 2D–3D perovskite film as compared to pristine 3D perovskite, ensuring effective bulk passivation in the relevant film. 相似文献
999.
Nguyen Tuan Thanh Tran Nghi H. Karacolak Tutku 《Analog Integrated Circuits and Signal Processing》2022,112(3):475-484
Analog Integrated Circuits and Signal Processing - This work presents a dual polarized microstrip patch antenna array with improved isolation and gain for in-band full-duplex wireless... 相似文献
1000.
Nguyen Thanh Tuan Nguyen Thanh Phuong Bouchara Frédéric 《Multidimensional Systems and Signal Processing》2022,33(3):945-979
Multidimensional Systems and Signal Processing - Encoding turbulent properties of dynamic textures (DTs) is a challenging issue of video understanding for various applications in computer vision.... 相似文献