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41.
Two novel sulfaguanidine series, six N-(N,N′-dialkyl/dibenzyl-carbamimidoyl) benzenesulfonamide derivatives and nine N-(N-alkyl/benzyl-carbamimidoyl) benzenesulfonamide derivatives, were obtained by desulfidative amination of easily accessible dimethyl arylsulfonylcarbonimidodithioates under catalyst- and base-free conditions. The newly synthesized compounds were tested for the inhibition of four different isozymes of human carbonic anhydrase (hCA I, II, IX and XII, EC 4.2.1.1). Both series reported here were inactive against the off-target isozymes hCA I and II (Ki>100 μM). Interestingly, all investigated compounds inhibited both target isozymes hCA IX and XII in the submicromolar to micromolar ranges in which Ki values spanned from 0.168 to 0.921 μM against hCA IX and from 0.335 to 1.451 μM against hCA XII. The results indicated that N-(N-alkyl/benzyl-carbamimidoyl) benzenesulfonamides were slightly more potent inhibitors than N-(N,N′-dialkyl/dibenzyl-carbamimidoyl) benzenesulfonamides. Among the evaluated compounds, N-n-octyl-substituted N-carbamimidoylbenzenesulfonamide showed the most significant activity with a Ki value of 0.168 μM against hCA IX, which was four-fold more selective toward this isozyme versus hCA XII. Again, another derivative from N-(N-alkyl/benzyl-carbamimidoyl) benzenesulfonamide series, N-p-methylbenzyl-substituted N-carbamimidoylbenzenesulfonamide, demonstrated superior inhibitory activity against hCA XII with a Ki value of 0.335 μM.  相似文献   
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Wireless Personal Communications - The paper addresses the narrowband direction of arrival estimation problem in the presence of multiplicative noise, namely, the local scatterers affect the...  相似文献   
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Water Resources Management - The present study develops a novel form of optimization framework to assess environmental flow in the reservoirs in which upstream and downstream river ecosystems and...  相似文献   
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Linear and weakly nonlinear stability analyses of thermosolutal convection in a couple-stress fluid with effects of helical force and rotation are performed. The governing nondimensional equations are solved using the normal modes. We have shown the effect of the helical force parameter, solutal Rayleigh number, Couple stress parameter, Lewis number, Taylor number, and Prandtl number on stationary and oscillatory convection regions and presented graphically. Solutal Rayleigh number, Couple stress parameter, Lewis number, and Taylor number have a stabilizing effect on the system whereas the helical force parameter has a destabilizing effect on the system. To study heat transport by convection we have derived the Ginzburg–Landau equation.  相似文献   
46.
Niobia (1 mol. %) doped Ceria Stabilized Zirconia (NbCSZ) powders were synthesized using a co-precipitation method. The synthesized powders were uniaxially compacted and sintered in air. The two-step sintering method was adopted to sinter the samples, and the sintering schedule was optimized based on density, grain size, the phase present, and the hardness of the sintered sample. It was observed that the two-step sintering method effectively suppressed the grain growth of NbCSZ samples and helped in achieving a finer grain size of 1.57 μm along with the hardness of 1195 HV10 and optimum fracture toughness value 6.20 MPa m1/2. The Low-Temperature Degradation (LTD) behavior of the sintered samples was estimated through an accelerated hydrothermal aging test, which revealed that the samples are highly resistant to LTD and shown no phase change even after 150 h of study. Moreover, the cytocompatibility of the NbCSZ was tested by culturing MG63 cells on the samples for 7 days. The NbCSZ was found to be highly biocompatible as evident from cell viability and metabolic activity assay.  相似文献   
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The Journal of Supercomputing - Recommender systems play an important role in dealing with the problems caused by the great and growing amount of information, and the collaborative filtering method...  相似文献   
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Production, assembly or logistic systems exist in widespread domains. It is agreed that more than 50% of life-cycle performance, costs and environmental impacts of such systems are due to those decisions that are made in their early design stages (Reich, Res Eng Design 28(4):411–419, https://doi.org/10.1007/s00163-017-0270-7, 2017). However, the large scale and multi-disciplinary essence of such systems make their design considerably challenging. Most of the design approaches follow a sequential approach such that the design in each lower level is finalized/frozen before proceeding to the next level. However, such approaches do not properly address the interaction between different design disciplines which may later lead to design inconsistencies. Therefore, this paper aimed to propose a modelling framework that allows having an integrated approach in the early design stages of such systems. To this end, first the framework prescribed developing an executable meta-architecture that can embody all the design requirements. Second, the framework describes the interconnections between the meta-architecture with certain supporting algorithms and optimization models. This allows generating and simulating different design alternatives and observing the impact of different design decisions on system integrated performance. Therefore, the proposed framework with its providing outcomes can be used to support the decision making in early design stages of such systems. The framework is applied in a real case study from the warehousing domain, which serves to show the practical application of the proposed framework.  相似文献   
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