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In the current study, using a semi-flexible quadritopic N-donor ligand, 5,5′-bipyrimidine (bpym), a new azide-based coordination polymer, [Co(bpym)(N3)2]n (1), was synthesized and structurally characterized via the single crystal X-ray diffraction along with the elemental analysis. Its treatment activity on the chronic obstructive pulmonary disease (COPD) would be evaluated and the related mechanism was explored. Firstly, the ELISA (enzyme linked immunosorbent assay) detection assay was performed and the levels of the inflammatory cytokines were measured. In addition to this, the NF-κB signaling pathway activation in the lung epithelial cells was measured with the real time RT-PCR (reverse transcription-polymerase chain reaction). Both six-membered rings containing nitrogen and the azide group on the designed drug molecule were confirmed by molecular docking simulation to have activities to the NF-kappaB.

The nature of inert gas bonding has always been an important topic. The bonds of noble gases cover the entire range of chemical bonds, from the weakest van der Waals forces, to non-covalent interactions, and to covalent bonds. Two types of methods were used to investigate the properties of chemical bonds in the inert gas inserted compound MNgBY with the transition metal M = Cu/Ag/Au and substituents Y = O/S/NH, one based on orbital analysis and the other based on electron density analysis. The NBO/NRT analysis shows that in these compounds there exists long-bonding striding the noble gas between the transitional metal and boron, similar to the noble gas insertion compounds HNgX of hydrohalide, and so a three-center four-electron bond exists among the M-Ng-B part. The electron density analyses show that the M-Ng bond between the metal Cu/Ag/Au and noble gas and the Ng-B bond in the Cu/Ag compounds are partial covalent but the Ng-B bond in Au compounds is a typical covalent bond. The large relativistic effects of Au cause the bonds in Au compounds shorter and stronger than the bonds in Ag/Cu compounds. The properties of the M-Ng and Ng-B bonds are not affected by substituents Y, but the bond lengths are sensitive to substituents.

Laser additive manufacturing (LAM) technology was applied to prepare Ti-22Al-25Nb alloy thin-wall sample. The characteristics and evolution mechanism of solidification microstructure were investigated, and the tensile properties at horizontal and vertical directions were discussed. The results indicated that the solidification microstructure in single deposition layer evolved as: plane crystal structure, cellular crystal structure, columnar dendrite structure and equiaxed dendrite structure, from the bottom to the top of the molten pool. During the solidification process, the temperature gradient and solidification velocity decided the grain growth morphology. However, the grain of the as-deposited materials grew up to thick equaxied structure when the upper layer was forming. The tensile properties at horizontal and vertical directions were not much different, both of these exhibited high strength and low ductility.

Understanding the effect of process parameters on microstructure is crucial to control or optimize microstructure for laser direct deposition process. Four thin-wall samples of TC11 titanium alloy are deposited with different process parameters. They showed different macro/micro-structure and mechanical properties. The reason is analyzed by temperature field of samples which are simulated by ANSYS software. Results show that, deposition with low laser power and slow scanning speed is conducive to reducing molten pool temperature and soaking time in β-phase region, refining original β grain and improving the plastic properties of the deposited parts. Deposition with high laser power and rapid scanning speed, combined with interlayer stay, is helpful to increase the cooling rate within α+β phase region, refine intragranular α lamellar and improve the tensile strength of deposited parts.

OBJECTIVE: To investigate the efficacy and safety of lamotrigine monotherapy in children with epilepsy via a systematic review. METHODS: PubMed, Cochrane, CNKI, VIP, CBM, Wanfang Data were searched for randomized controlled trials (RCTs) of lamotrigine monotherapy in children with epilepsy. Literature screening, data extraction, and quality assessment were performed according to the method recommended by Cochrane Collaboration. RevMan 5.2 software was used to conduct the Meta analysis. RESULTS: A total of 9 RCTs involving 1 016 participants were included. Lamotrigine yielded a significantly lower complete control rate of seizure than ethosuximide, but the complete control rate of seizure showed no significant differences between lamotrigine and carbamazepine/sodium valproate. Patients treated with lamotrigine had a significantly lower incidence rate of adverse events than those treated with carbamazepine, but the incidence rate of adverse events showed no significant differences between patients treated with lamotrigine and sodium valproate/carbamazepine. The drop-out rate showed no significant differences between the three treatment groups. CONCLUSIONS: Lamotrigine is an ideal alternative drug for children who do not respond to traditional antiepileptic medication or experience significant adverse reactions; however, more high-quality RCTs with a large sample size and a long follow-up time are needed to confirm these conclusions.

Phase equilibrium conditions of gas hydrate in several systems were measured by the step-heating method using the cylindrical transparent sapphire cell device. The experimental data for pure CH 4 or CO 2 + deionized water systems showed good agreement with those in the literatures. This kind of method was then applied to CH 4 /CO 2 + sodium dodecyl sulfate (SDS) aqueous solution, CH 4 /CO 2 + SDS aqueous solution + silica sand, and (CH 4 + C 2 H 6 + C 3 H 8 ) gas mixture + SDS aqueous solution systems, where SDS was added to increase the hydrate formation rate without evident influence on the equilibrium conditions. The feasibility and reliability of the step-heating method, especially for porous media systems and gas mixtures systems were determined. The experimental data for CO 2 + silica sand data shows that the equilibrium pressure will change significantly when the particle size of silica sand is less than 96 μm. The formation equilibrium pressure was also measured by the reformation of hydrate.

To understand the characteristics of pro-apoptotic gene SjBAD of Schistosoma japonicum, such as its biology, immunology, and transcriptional expression, and evaluate its potential of the recombinant protein as a vaccine candidate for schistosomiasis.SjBAD was amplified by PCR and subeloned into a pET-28a(+) vector, and the recombinant plasmid was transformed into competent E. coli BL21 for producing recombinant protein. The expressions of SjBAD in different development stages of schistosomula and 42-day male and female worms were determined by real-time PCR. The immunogenicity of the recombinant protein was analyzed by Western blotting and ELISA. The potential of this protein as a vaccine candidate molecule was assessed by testing the worm reduction rate and liver egg reduction rate in the BALB/c mice immunized by the recombinant antigen SjBAD.SjBAD was successfully cloned, the recombinant plasmid pET-28a(+)-SjBAD was successfully expressed in E. coli, and the molecular weight of the recombinant protein was around 22 kDa. Western-blotting showed that the recombinant protein had good immunogenicity. The recombinant protein could induce high level of specific IgG antibodies in the BALB/c mice. SjBAD was expressed in all tested 7-, 14-, 21-, 28-, 35- and 42-day worms, and was highly expressed in 14-day schistosomula, while the expression level in 42-day male worms was higher than that in 42-day female worms. Two in- dependent animal trials showed that 30.82% and 27.87% worm reduction rates, as well as 42.52% and 45.84% liver eggs reduction rates were obtained in the rSjBAD vaccinated group compared with those of the blank control group (both P0.05).The proapoptotic gene SjBAD is successfully cloned and expressed. The gene is expressed in different development stages of S. japonicum. The rSjBAD vaccinated BALB/c mice can obtain a partial protective immunity against S. japonicum infection.

The AR model method was applied in this paper to analyze the information extraction of vehicle vibration signals in highway traffic flow. Based on the sample data and appropriate AR model method, the feature vectors were used to distinguish different vehicle models. The proposed feature method in vehicle signal recognition technology can achieve the requirement of auxiliary determination. It demonstrated that the feasibility of model identification and feature extraction using the highway vehicle vibration signal. The result showed that the AR model is an effective method in vehicle type classification.

Diabetic neuropathic pain is a common clinical problem and remains difficult to treat with classic analgesics. Spinal dorsal horn neurons are important in mediating nociceptive signaling, and the hyperactivity of these neurons is critical in diabetic neuropathy. In this study, we determined the GABA B receptor expression level in dorsal horn neurons in streptozotocin (STZ)-induced diabetes in rats by using reverse-transcription polymerase chain reaction (RT-PCR) and western blot analyses. Mean blood glucose concentrations were significantly higher and the paw withdrawal threshold was significantly lower in STZ-treated rats than in saline-treated rats. Immunohistochemical staining showed that the GABA B receptor was extensively expressed in the spinal dorsal horn neurons. The GABA B1 mRNA level decreased in a time-dependent manner in STZ-treated rats compared with saline-treated controls. Furthermore, the protein expression level revealed by western blot analysis was lower in STZ-treated rats than in saline-treated rats. These data suggest that GABA B receptors are downregulated in the spinal dorsal horn in this model of STZ-induced diabetic neuropathic pain. The reduction of GABA B expression may contribute to the hyperactivity of spinal dorsal horn neurons and diabetic neuropathic pain.

Distributed Source Coding (DSC) is one of the most promising collaborative information processing technologies for Wireless Video Sensor Networks (WVSN) because its low complexity video encoder is suitable for resource limited sensor nodes. Generic sensor nodes with limited energy are restricted with computation and communication capabilities, therefore, traditional video coding such as MPEG-4 or H.264 is too complicated for sensor nodes. In this paper, the concept and the predominant methods of distributed source coding are introduced briefly. Moreover, how to apply distributed source coding appropriately in multi-source multi-camera wireless video sensor network is investigated. Traditional distributed source coding technology is asymmetric but sensor nodes in WVSN are homogenous, therefore, symmetric distributed source coding appropriate for multi-camera wireless video sensor networks is discussed. Moreover, multi-source symmetric distributed source coding is investigated because there are a mass of sensor nodes in the WVSN. As we known, it is the first exploration about multi-source distributed source coding technology.

Mobility models characterize mobile users' movements of location, velocity and acceleration for the difficulty to obtain traces in real world. A classification of proposed and applied mobility models for MANET (mobile ad hoc networks) are given in this article firstly. The probability distribution of nodes is a basic foundation for the theoretic research of mobility models for MANET, such as the work of network connectivity, average path length, network capacity etc. Researchers have found non-uniform node distribution impairs the validity and credibility of many aspects of wireless ad hoc networks, such as protocol evaluation and connectivity, for they are both based on uniformity node distribution assumption. Integral geometry method is employed in this paper to analyze the node probability distribution of random direction mobility model in MANET. The results of this paper provide precise theoretic foundations, simulations and applications of ad hoc network of random direction mobility model.

The interfacial tensions between methane and aqueous solutions of different contents of VC-713 (a terpolymer of N-vinylpyrrolidone, N-vinylcaprolactam, and dimethylamino-ethyl-methacrylate) were measured at different temperatures and pressures in the hydrate formation region. The surface adsorption free energies of methane were calculated accordingly in order to investigate the effect of this kinetic inhibitor on the nucleation of hydrate. The results show that the presence of VC-713 lowers the interfacial tension, increasing the concentration of methane on the surface of the aqueous phase, and thus promotes nucleation of hydrate at the gas/liquid interface. Additionally, the measured interfacial tension data suggest that VC-713 tends not to form micelles in water. Subsequently, the lateral growth rate of hydrate film on the surface of a methane bubble suspended in the aqueous phase was measured at different pressures to investigate the effect of VC-713 on the growth of hydrate. The results show that the lateral growth rate of hydrate film from aqueous VC-713 solution is much lower than that from pure water, demonstrating that VC-713 significantly inhibits the hydrate growth. The mechanism of the inhibition is also discussed.

WSN (Wireless Sensor Network) is constrained by limited radio propagation range as well as battery life. Multicast is an efficient method to support group communication and decrease communicating energy. It is challenging to design multicast routing protocol for WSN. The mesh-based protocol ODMRP (On-Demand Multicast Routing Protocol) is our focus. Its forwarding group can be used not only for delivering multicast traffic from base station to sensor nodes but also for reverse routing from sensor nodes to the base station to assemble data. The feasibility and improvement of ODMRP for WSN are analyzed by modeling and simulation. Results show that associated with network design including node density and initial energy we can apply ODMRP efficiently.

In this paper, we firstly study the connectivity of ad hoc networks and establish the correlations of connectivity with average node degree. Then, based on the simulation result of connectivity, we present a probabilistic flooding algorithm that can tradeoff the efficiency and reliability by using weighting factor. Thus, we treat the well-known contradictions in our new algorithm. Our simulation results show that, with the choice of an optimal flooding probability by using weighting factor, we can get a great deal of overhead gain with a little loss of packet delivery ratio.

We make some modifications in this paper to the DAP-NAD-CJ (deterministic adaptable priority net access delay with cycle jump) algorithm for multicast applications. The new algorithm assigns wireless channel access slot unevenly between stations in the network so that the multicast source can access channel as fast as possible. We then proved by calculations and simulations that the modified algorithm outperforms DAP-NAD-CJ greatly in both single priority and multi-priority networks.

In this paper, we proposed an improved NAD (network access delay) algorithm for MIL-STD-188-220C that is named as DAP-NAD-CJ. In our new algorithm, the implicit token passing scheme was modified so that tokens can effectively jump over stations without message, and thus can find active stations as fast as possible. Firstly, we analyzed our algorithm mathematically in the case of single priority network. Then simulations were presented in a multi-priority network. Mathematical and simulation results showed that our DAP-NAD-CJ algorithm outperforms DAP-NAD and DAP-NAD-R algorithms