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31.
The Journal of Supercomputing - Depression is the most prevalent mental disorder that can lead to suicide. Due to the tendency of people to share their thoughts on social platforms, social data...  相似文献   
32.
Legionella pneumophila is the causative agent of Legionnaires’ disease, a serious form of pneumonia. Its macrophage infectivity potentiator (Mip), a member of a highly conserved family of FK506-binding proteins (FKBPs), plays a major role in the proliferation of the gram-negative bacterium in host organisms. In this work, we test our library of >1000 FKBP-focused ligands for inhibition of LpMip. The [4.3.1]-bicyclic sulfonamide turned out as a highly preferred scaffold and provided the most potent LpMip inhibitors known so far. Selected compounds were non-toxic to human cells, displayed antibacterial activity and block bacterial proliferation in cellular infection-assays as well as infectivity in human lung tissue explants. The results confirm [4.3.1]-bicyclic sulfonamides as anti-legionellal agents, although their anti-infective properties cannot be explained by inhibition of LpMip alone.  相似文献   
33.
In this study, two different monomers, namely hexafluorobutyl acrylate (HFBA) and diethylaminoethyl methacrylate (DEAEMA) were individually used to modify graphene oxide (GO) nanosheets via environmentally friendly plasma enhanced chemical vapor deposition (PECVD) method. The results from instrumental analyses confirmed the successful deposition of respective functional material onto the nanomaterials. Modified GOs were used as the nano-fillers to develop composite polyethersulfone (PES) ultrafiltration (UF) membrane with improved surface properties for oily solution treatment. All the developed membranes were characterized with a series of analytical instruments to support the findings of membrane filtration performance. The results indicated that the membrane incorporated with DEAEMA-GOs (coated with hydrophilic polymer) could achieve better results in terms of oil rejection, antifouling resistance and water recovery rate than the membrane incorporated with HFBA-GOs (coated with hydrophobic polymer). This is due to the reduced agglomeration between modified GOs as well as better interaction of hydrophilic-coated GOs with polymer membrane. Compared to the pure water flux of the membrane incorporated with unmodified GO, the membrane incorporated with DEAEMA-GO achieve approximately 85% higher value with oil removal rate remained almost unchanged (98.94% rejection).  相似文献   
34.
The objective of this work was to investigate the effect of chemical composition and segment number (n) on gelation, stiffness, and degradation of hydroxy acid-chain-extended star polyethylene glycol acrylate (SPEXA) gels. The hydroxy acids included glycolide (G), L-lactide (L), p-dioxanone (D) and ?-caprolactone (C). Chain-extension generated water soluble macromers with faster gelation rates, lower sol fractions, higher compressive moduli, and a wide-ranging degradation times when crosslinked into a hydrogel. SPEGA gels with the highest fraction of inter-molecular crosslinks had the most increase in compressive modulus with n whereas SPELA and SPECA had the lowest increase in modulus. SPEXA gels exhibited a wide range of degradation times from a few days for SPEGA to a few weeks for SPELA, a few months for SPEDA, and many months for SPECA. Marrow stromal cells and endothelial progenitor cells had the highest expression of vasculogenic markers when co-encapsulated in the faster degrading SPELA gel.  相似文献   
35.
In this paper we address a hybrid flow shop scheduling problem considering the minimization of the sum of the total earliness and tardiness penalties. This problem is proven to be NP-hard, and consequently the development of heuristic and meta-heuristic approaches to solve it is well justified. So, we propose an ant colony optimization method to deal with this problem. Our proposed method has several features, including some heuristics that specifically take into account both earliness and tardiness penalties to compute the heuristic information values. The performance of our algorithm is tested by numerical experiments on a large number of randomly generated problems. A comparison with solutions performance obtained by some constructive heuristics is presented. The results show that the proposed approach performs well for this problem.  相似文献   
36.
37.
Integration of front-end electronics with 2D capacitive micromachined ultrasonic transducer (CMUT) arrays has been a challenging issue due to the small element size and large channel count. We present design and verification of a front-end drive-readout integrated circuit for 3D ultrasonic imaging using 2D CMUT arrays. The circuit cell dedicated to a single CMUT array element consists of a high-voltage pulser and a low-noise readout amplifier. To analyze the circuit cell together with the CMUT element, we developed an electrical CMUT model with parameters derived through finite element analysis, and performed both the pre- and postlayout verification. An experimental chip consisting of 4 X 4 array of the designed circuit cells, each cell occupying a 200 X 200 microm2 area, was formed for the initial test studies and scheduled for fabrication in 0.8 microm, 50 V CMOS technology. The designed circuit is suitable for integration with CMUT arrays through flip-chip bonding and the CMUT-on-CMOS process.  相似文献   
38.
The adsorption of Acid Red 57 (AR57) onto calcined-alunite was examined in aqueous solution in a batch system with respect to contact time, pH and temperature. The first-order, pseudo-second-order kinetic and the intraparticle diffusion models were used to describe the kinetic data and the rate constants were evaluated. The experimental data fitted very well the pseudo-second-order kinetic model and also followed the intraparticle diffusion model up to 90 min. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were also determined. The equilibrium data are successfully fitted to the Langmuir adsorption isotherm. The Langmuir isotherm constant, K(L), was used to evaluate the changes of free energy, enthalpy and entropy of adsorption for the adsorption of AR57 onto calcined-alunite. The results indicate that calcined-alunite could be employed as low-cost material for the removal of acid dyes from textile effluents.  相似文献   
39.

Apart from the the increasing demand of smartphones in human-to-human (H2H) communications, the introduction of machine-to-machine (M2M) devices poses significant challenges to wireless cellular networks. In order to offer the ability to connect billion of devices to propel the society into a new era of connectivity in our homes, officies and smart cities, we design novel radio resource sharing algorithms in a H2H/M2M coexistence case to accommodate M2M communications while not severely degrading existing H2H services. We propose group-based M2M communications that share the same spectrum with H2H communications through device-to-device (D2D) communication, as one of the technology components of 5G architecture. First, we formulate radio resource sharing problem as a sum-rate maximization, problem for which the optimal solution is non-deterministic polynomial-time hard (NP-hard). To overcome the computational complexity of the optimal solution, we model the resource sharing problem as a bipartite graph, then propose a novel interference-aware graph-based resource sharing scheme using a fixed M2M transmit power. To further enhance the protection of H2H services, we introduce an adaptive power control mechanism into the interference-aware graph-based resource sharing scheme. M2M transmit power is efficiently adjusted using one among the two following alternative controllers, namely, either the proportional integral derivative (PID) or the fuzzy logic. The latter is proposed within the aim to assure the desired quality-of-service (QoS) of H2H users and increase the efficiency of M2M spectrum usage. In both cases (fixed and adaptive), a centralized and a semi-distributed instantiations are given. Simulation results show that adaptive M2M radio resource sharing scheme using fuzzy logic is the one that achieves the best compromise. In fact, it guarantees H2H performance in terms of throughput and fairness while maximizing the efficiency of M2M spectrum usage. Simulation results also show that in spite of its quite good performance, semi-distributed M2M resource sharing instantiation achieves them with a decline of up to 10% in terms of H2H throughput compared to the centralized instantiation. This is achieved through a markedly lower communication overhead.

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40.
Experimental study of temperature‐ and frequency‐dependent properties of the commercially available shape memory polymer Tecoflex? EG 72D (TFX) (Lubrizol, USA) using dynamic mechanical analysis (DMA) technique is presented. Temperature scan DMA tests have been carried out in three distinct deformation modes, uniaxial tension, three‐point bending, and simple torsion, using two different testing rigs at different test parameters (frequency, strain amplitude, and heating rate) in temperatures ranging from below to above the glass transition temperature. The influence of different test parameters and some discrepancies in the temperature‐dependent storage and loss moduli (and hence the loss factor) measured by DMA in different deformation modes are discussed.  相似文献   
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