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The electronic structure and thermoelectric properties of monolayer Bi 2 Te 2 Se were studied by density functional theory and semi-classical Boltzmann transport equation. The band gap with TB-mBJ can be improved for monolayer Bi 2 Te 2 Se. Monolayer Bi 2 Te 2 Se have ultra-low thermal conductivity comparing with other well-known two-dimensional materials. The monolayer Bi 2 Te 2 Se can improve electrical conductivities. ZT increases with increasing temperature for monolayer Bi 2 Te 2 Se. Comparing to GGA, TB-mBJ has larger ZT value in p-type doping. Monolayer Bi 2 Te 2 Se have larger ZT comparing with other well-known two-dimensional materials. Our calculated results show that our calculation greatly underestimates ZT value, therefore, monolayer Bi 2 Te 2 Se should have a higher ZT value. • Monolayer Bi 2 Te 2 Se have ultra-low thermal conductivity. • The monolayer Bi 2 Te 2 Se can improve electrical conductivities. • TB-mBJ can't reduce the electronic thermal conductivity. • Comparing to GGA, TB-mBJ has larger ZT value in p-type doping. • Monolayer Bi 2 Te 2 Se have larger ZT comparing with other well-known two-dimensional materials. [ABSTRACT FROM AUTHOR]

Sepsis is characterized as exceed inflammation response and multiple organs dysfunction. Many articles suggested that mesenchymal stem cells can alleviate the inflammation and improve the survival rate of inflammatory animal models, however, the mechanism is still unclear. This study aimed to test the hypothesis that rat adipose-derived mesenchymal stem cells (ADMSCs) produce a amount of soluble tumour necrosis factor receptor 1 (sTNFR1), which ameliorated liver injury and inflammation and increased the survival rate of septic rat model.120 adult male Sprague-Dawley rats were randomly divided into 4 groups: sham-operated (Sham), sepsis-induced by cecal ligation and puncture (CLP), shNC (injected 1 × 106 ADMSCs with transfected with scramble shRNA 1 h after CLP), and shsTNFR1 (injected 1 × 106 ADMSCs with transfected with sTNFR1 1 h after CLP). The serum sTNFR1 levels were the lowest in Sham and highest in shNC group. ADMSCs could decrease the levels of pro-inflammatory cytokines such as TNF-α, IL-6, AP-1 c-jun and NF-κB p56 after CLP administration, whereas this result was weaken by shsTNFR1 administration. Moreover, shNC had an increased levels of the anti-inflammatory factor IL-10 compared with CLP, and this change could be weakened in shsTNFR1 administration. More importantly, ADMSCs could improve the survival rate of CLP-induced septic rats. Therapeutically administered ADMSCs secrete sTNFR1, which alleviated the liver injury and inflammatory response. Additionally, ADMSCs also ameliorated the systematic inflammation and increased the survival rate of septic rats. • ADMSCs could produce numerous sTNFR1 under inflammatory stimulation. • ADMSCs transplanted into the injury organ, liver. • ADMSCs could alleviate the liver injury and inflammation via secreting sTNFR1. [ABSTRACT FROM AUTHOR]

Hybrid wireless mesh networks are more suitable to tunnels in underground mines because mesh clients can perform the routing functionality and provide end-user applications. Types of data transmitted among hybrid wireless mesh networks in underground mines are diverse and power supply of clients is limited. Using virtual potential field, a routing algorithm is proposed to support data-differentiated service in hybrid wireless mesh networks. Based on network parameters, the hybrid wireless mesh networks are abstracted as potential fields. The hop count is used to build the depth potential field. The residual energy of nodes is converted into penalty factor to symbolize the used buffer spaces of nodes, which is used to construct resource potential field to support different types of data. According to the different demands of data transmission, the proportion of these two potential fields is adjusted by a regulatory factor to form a hybrid potential field. The data packets are driven to move toward the gateway in the hybrid potential field at the same time to achieve high quality of service. Simulation results demonstrate that the proposed routing algorithm has shown better performance on end-to-end delay, delivery ratio, and network lifetime, compared with similar algorithms. [ABSTRACT FROM AUTHOR]

Hybrid wireless mesh networks are suitable for complex environment communication in coal mine. Mesh clients with application service and routing function in hybrid wireless mesh networks can form a highly robust hybrid network with mesh routers. The processes of nutrient flux transfer and path choice in Physarum network are similar to data transmission and routing selection in hybrid wireless mesh networks. In this article, we use Physarum-inspired autonomic optimization model to design a Physarum-inspired multi-parameter adaptive routing protocol to improve the service quality of coal mine hybrid wireless mesh networks. Physarum-inspired multi-parameter adaptive routing protocol has achieved distributed routing decision by drawing the hybrid wireless mesh network parameters into Poisson’s equation of Physarum-inspired autonomic optimization model to measure the quality of link and implements two adjustment strategies to make the protocol more adaptive. The resource-dependent adjustment, which considers the irreversible energy consumption and recoverable buffer occupation, makes the energy consumption problem prominent when there is a lack of energy. The position-dependent adjustment makes routing decision efficient according to the load of different positions, which is caused by many-to-one data transmission model in coal mine. Based on NS2, simulation experiments are performed to evaluate the performance of Physarum-inspired multi-parameter adaptive routing protocol, and the results are compared with those of ad hoc on-demand distance vector, HOPNET, ANT-DSR, and Physarum-inspired routing protocols. The experimental results show that the route path selected by Physarum-inspired multi-parameter adaptive routing protocol is better than those selected by the other four protocols in the performance of average end-to-end delay and delivery ratio. The balance of energy consumption and network load is achieved and the network lifetime is effectively prolonged when using Physarum-inspired multi-parameter adaptive routing protocol. [ABSTRACT FROM AUTHOR]

Mesh clients in hybrid wireless mesh networks can perform the routing functionality, as well as provide end-user applications that are more suitable for tunnels, to improve the connectivity of backbone networks. In this article, based on the diversity of data and limited power supply of mesh clients in hybrid wireless mesh networks in underground mines, we propose a multi-criteria routing metric to support data-differentiated service. This routing metric divides data into two types: urgent and non-urgent. End-to-end delay is calculated when transmitting urgent data, and hop count and link load are measured when transmitting non-urgent data. In order to optimize the utilization of mesh clients and to prolong the network lifetime, mesh clients and mesh routers are given different weights in the calculation of hop count. Based on the QualNet7.1 simulation platform, the performance of the proposed routing metric in transmitting urgent and non-urgent data is evaluated through numerous simulations. Simulation results indicate that the routes selected using the proposed routing metric can effectively reduce the average end-to-end delay when transmitting urgent data and reduce the utilization rate of mesh clients while simultaneously guaranteeing the capability of the network when transmitting non-urgent data. This finding satisfies the differentiated service requirements of data of different types for hybrid wireless mesh networks in coal mines. [ABSTRACT FROM AUTHOR]

Energy is an extremely critical resource for battery-powered wireless sensor networks. Since data transmission typically consumes more energy than any other activities on a sensor node, it is of great importance to design energy optimized routing algorithm to achieve both energy efficiency and energy balance together, in order to prolong the network lifetime. In this paper, with the help of the concept of potential field in physics, we design a distributed energy optimized routing by constructing a hybrid potential field. The goal of this basic approach is to force packets to move toward the sink at the same time to achieve energy balance among neighbors. We adopt the social welfare function from social sciences to predict equality of residual energy of neighbors after selecting different next nodes, which is used to compute the potential value in energy balance potential field. Simulation results show that the algorithm effectively extends the network lifetime, has good performance on energy balance of sensors, and decreases the average hop of data transmission with the increase of the number of sinks, compared with similar algorithms. [ABSTRACT FROM AUTHOR]