We propose a packet routing strategy with a tunable parameter based on the local structural information of a scale-free network. As free traffic flow on the communication networks is key to their normal and efficient functioning, we focus on the network capacity that can be measured by the critical point of phase transition from free flow to congestion. Simulations show that the maximal capacity corresponds to alpha= -1 in the case of identical nodes' delivering ability. To explain this, we investigate the number of packets of each node depending on its degree in the free flow state and observe the power law behavior. Other dynamic properties including average packets traveling time and traffic load are also studied. Inspiringly, our results indicate that some fundamental relationships exist between the dynamics of synchronization and traffic on the scale-free networks.

A thermal reaction of Li3N and GaCl3 in which benzene was used as the solvent under pressure has been carried out for the preparation of 30-nanometer particles of gallium nitride (GaN) at 280°C. This temperature is much lower than that of traditional methods, and the yield of GaN reached 80%. The x-ray powder diffraction pattern indicated that sample was mainly hexagonal-phase GaN with a small fraction of rocksalt-phase GaN, which has a lattice constant a = 4.100 angstroms. This rocksalt structure, which had been observed previously only under high pressure (at least 37 gigapascals) was observed directly with high-resolution electron microscopy.

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Nanocrystallites of non-stoichiometric copper sul®des were synthesized via the reaction between [Cu(NH 3 ) 4 ] 2z and thiourea in sealed autoclaves at the low temperature of 60 ³C for 3 h. Thiourea played a key role in the process of Cu 9 S 8 nanocrystal formation. Through adjusting the redox atmosphere, Cu 7 S 4 and CuS were obtained from the freshly formed Cu 9 S 8 nanocrystals. The products were characterized by means of X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), FT-IR spectroscopy and transmission electron microscopy (TEM) techniques. The Cu : S atomic ratios for Cu 9 S 8 and Cu 7 S 4 were 9 : 8.08 and 7 : 4.05, respectively, analyzed by inductively coupled plasma (ICP) spectroscopy. The possible mechanism of phase transformation among copper sul®des (Cu 9 S 8 , CuS, and Cu 7 S 4 ) was discussed. The optical properties of the products were also recorded by means of UV±vis absorption, and photoluminescence spectroscopy.

With inflammation increasingly recognized as a key factor that influences fracture healing, the immunologic response is considered to play a pivotal role in determining implant-mediated osteogenesis. Herein, this paper demonstrates that modification of the surface hydrophilicity of Ti surface oxides can be utilized to control immune response by steering the macrophage polarization toward pro- or anti-inflammation phenotype. Enhanced anti-inflammatory and prohealing performance of macrophages is observed on hydrophilic surfaces compared to hydrophobic ones. Further study on the detailed mechanism demonstrates that the surface hydrophilicity controls specific proteins (fibronectin and fibrinogen) adsorption and conformation, which activate different signaling pathways (PI3K and NF-κB) through selective expression of integrin β1 or β2 to influence the behaviors of macrophages. Thus, this study presents a mechanism of macrophage polarization modulated by surface hydrophilicity for the surface design of advanced implant materials with satisfactory anti-inflammatory and osteogenesis-promoting properties.