Zhukromann4462

Single-walled carbon nanotubes (SWCNTs) are potential antibacterial material, and their antibacterial activity in aqueous solutions relies on surfactants to create strong interactions with bacterial cells. Here, we designed and synthesized a new family of cationic surfactants by introducing different positively charged hydrophilic heads, i.e., -(CH2)6N+(CH3)3Br-, -(CH2)2N+(CH3)3Br- and -(CH2)2N+PyridineBr-, to cardanol obtained from cashew nut shell liquid. These surfactants can efficiently disperse SWCNTs in aqueous solutions because benzene rings and olefin chains in cardanol enable strong π-stackings on SWCNTs. A much higher fraction of SWCNTs can be dispersed individually as compared to the commonly used surfactants, e.g., dodecylbenzene-sulfonate sodium (SDBS). SWCNTs dispersed in the cardanol-derived surfactants demonstrate significantly improved antibacterial activities. At the concentration of 0.5 wt.%, their minimum inhibitory concentration is 0.33 and 0.02 μg/mL against E. coli and S. aureus, respectively, which is only 0.8-1.5% of that of SDBS dispersed SWCNTs. The intense antibacterial activity can be attributed to better dispersion of SWCNTs and positive charges introduced by hydrophilic heads, which attract to negatively charged bacterial cell surfaces. These cardanol-derived surfactants are promising as sustainable surfactants for enabling various SWCNT applications. © 2020 IOP Publishing Ltd.Breathing variations during 4D CT imaging often manifest as geometric irregularities known as respiratory-induced image artifacts and ultimately effect radiotherapy treatment efficacy. To reduce such image artifacts we developed Respiratory Adaptive Computed Tomography (REACT) to trigger CT acquisition during periods of regular breathing. For the first time, we integrate REACT with clinical hardware and hypothesize that REACT will reduce respiratory-induced image artifacts ≥ 4 mm compared to conventional 4D CT. 4D image sets were acquired using REACT and conventional 4D CT on a Siemens Somatom scanner. Scans were taken for 13 respiratory traces (12 patients) that were reproduced on a lung-motion phantom. Motion was observed by the Varian RPM system and sent to the REACT software where breathing irregularity was evaluated in real-time and used to trigger the imaging beam. REACT and conventional 4D CT images were compared to a ground truth static-phantom image and compared for absolute geometric differences wit© 2020 Institute of Physics and Engineering in Medicine.The electronic structure and thermoelectric transport in SnSe and its alloy with Cu2Se have been studied using the First principles technique and semi classical Boltzmann transport theory. Our study reveals that SnSe is p-type with indirect band gap of 0.66 eV, while the alloy is phase separated and n-type with negligible indirect band gap of 0.064 eV. In both cases, two fold degeneracy in band extrema have been observed within the range of 25 meV. Delocalization of Se lone pair has been observed due to Cu substitution in Sn sites, which is supposed to lower its lattice thermal conductivity. A chemical potential map has been generated obeying thermodynamic restrictions to predict the possible existence of secondary phases. Our study shows the existence of SnSe2 as a secondary phase, while the possibility of Cu2Se as a secondary phase is negligible due to its higher formation energy. We calculated the transport coefficients as a function of carrier concentration and temperature to understand the range of optimr carrier scattering are most dominant in the alloy. Alloy scattering with U = 2 eV also contribute significantly. © 2020 IOP Publishing Ltd.A vibration sensor is presented mimicking the structure of the Pacinian Corpuscle. A multi-step casting process is used to create a 5 mm diameter sensor with a liquid metal core, elastomer dielectric, and graphite counter electrode creating a spherical capacitive sensing element with sensitivities on the order of 10 ∆pF/mm. A model for the capacitance change of the spherical capacitor as it is formed is developed and its findings support the sensitivities observed. Various elastomer dielectric compositions with integrated barium titanate nanoparticles are tested to increase the dielectric constant. The biological acoustic filter within the corpuscle is mimicked using alternating cast layers of oligomers and elastomers around the spherical sensor element. Vibration sensing is characterized over the low frequency range of 10-300Hz and the minimum detectable sensitivity is found to be 1 µm with a low power requirement of 7 mW. DNA inhibitor The artificial Pacinian corpuscle has potential applications in tactile sensing and seismic monitoring devices. Not subject to copyright in the USA. Contribution of the US Army Research Laboratory.Graphene oxide (GO) and gold ions (Au3+) can be simultaneously reduced and self-assembled into a three-dimensional (3D) graphene/Au composite (GA/Au) porous structure at room temperature via a one-step γ-ray irradiation. The microstructure of GA/Au composites were observed under different magnifications and the pores observed to be a uniform 3D honeycomb-like porous structure. In addition, Au nanoparticles were homogeneously attached to graphene sheets and had a typical diameter of 6 nm. These GA/Au composites were analyzed and characterized by X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), and thermal gravity analysis (TGA). Due to synergistic catalysis between graphene and Au nanoparticles, GA/Au composites catalyzed 4-nitrophenol with excellent catalytic performance, even at concentrations up to 6.48×10-3 M. When the concentration of 4-nitrophenol was 2.16×10-3 M and 4.22×10-3 M, the first-order kinetic constants were 2.00 and 1.43 min-1, respectively. © 2020 IOP Publishing Ltd.Due to the increasing aging population and the high probability of sport injury among young people nowadays, it is of great demand to repair/regenerate diseased/defected osteochondral tissue. Given that osteochondral tissue mainly consists of a subchondral layer and a cartilage layer which are structurally heterogeneous and mechanically distinct, developing a biomimetic bi-phasic scaffold with excellent bonding strength to regenerate osteochondral tissue is highly desirable. Three-dimensional (3D) printing is advantageous in producing scaffolds with customized shape, designed structure/composition gradients and hence can be used to produce heterogeneous scaffolds for osteochondral tissue regeneration. In this study, bi-layered osteochondral scaffolds were developed through cryogenic 3D printing, in which osteogenic peptide/β-tricalcium phosphate/poly(lactic-co-glycolic acid) water-in-oil composite emulsions were printed into hierarchically porous subchondral layer while poly(D,L-lactic acid-co-trimethylene carbonate) water-in-oil emulsions were printed into thermal-responsive cartilage frame on top of the subchondral layer.