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Due to the sharing and open-access characteristics of the wireless medium, wireless sensor networks (WSNs) can be easily attacked by jammers. To mitigate the effects of a jamming attack, one reliable solution is to locate and remove the jammer from the deployed area within the WSN. To realize the jammer’s localization in the WSN, many range-free methods have been proposed. However, most of these methods are sensitive to the distribution of nodes and the parameters of the jammer. For this reason, a jammer location-aware method based on Fibonacci branch search (FBS) is proposed in this article. First, the interference region is estimated by using the interference region mapping service of sensors in wireless sensor networks. Then, the search point is selected in the jamming area and the fitness function is designed according to the average distance from the search point to the boundary sensor. According to the basic branch structure and interactive search rules, the global optimal solution is obtained in the jamming area. Finally, the position of the search point with the best fitness value is used as the estimation of the jammer position. Compared with the existing typical range-free methods, rich simulation experiments demonstrate that the FBS algorithm is superior in the location-aware method for jammers with a higher precision and a lower sensitivity to the distribution of nodes and the parameters of the jammer, respectively.

With the widespread application of Internet of things (IoT), the interference problem becomes more and more serious, which results in not only the poor network performance but also the increased energy consumption of IoT nodes. Therefore, in this paper, we investigate the problem of how to locate the interference sources and infer their communication relationships in the cognitive radio IoT (CR-IoT) deployment scenario. First, we utilize MDS-MAP(P) algorithm with dynamic power control to realize cooperative self-localization of the CR-IoT nodes, which is more energy-efficient than all the IoT nodes equipped with global positioning system (GPS) receivers. Then, we propose a non-cooperative localization method to determine the inference sources with the angle of arrivals (AoAs) measured by the CR-IoT nodes. Finally, the communication relationship between interference sources can be inferred based on the association rule of signals. The network simulation results validate that the proposed methods can locate the interference sources accurately with low energy consumption and correctly infer their communication relationships, which is helpful for the interrupted CR-IoT nodes to take a specific opportunistic transmission policy to reduce their energy consumption.

In heterogeneous environments, the Internet of Things (IoT) combined with mobile ad hoc network (MANET), i.e., MANET-IoT network, becomes more attractive to end users and economically successful. However, the introduction of MANET potentially makes the system more prone to attacks due to its lack of centralized management, weak connectivity, and resource constraints. To enhance the network robustness to intentional attacks, the critical nodes of the MANET-IoT network should be firstly identified and then protected. Most of the existing methods for identifying critical nodes usually focus on static networks or a single topology snapshot in dynamic networks without considering the correlation between topology snapshots, which cannot effectively deal with the dynamic changes in the topology of MANET-IoT networks. In this paper, a dynamic critical node identification (DCNI) method is proposed. First, we propose a comprehensive metric to measure the node importance in the topology snapshot. Then, we introduce a sliding time window to filter out the topology snapshots which have a close correlation with the current snapshot, and fuse the importance values of the same node in different topology snapshots. Finally, the critical nodes are selected based on the ranking result of fused importance. Thereafter, the port hopping mechanism could be applied to the critical nodes for enhancing network defense capability. The simulation results show that the proposed method is more effective in identifying critical nodes than existing static methods in MANET-IoT networks, and the port hopping mechanism can improve network defense significantly to denial of service (DoS) attacks.

As the demand for location services increases, research on location technology has aroused great interest. In particular, signal-based fingerprint location positioning technology has become a research hotspot owing to its high positioning performance. In general, the received signal strength indicator (RSSI) will be used as a location feature to build a fingerprint database. However, at different locations, this feature distinction may not be obvious, resulting in low positioning accuracy. Considering the wavelet transform can get valuable features from the signals, the long-term evolution (LTE) signals were converted into wavelet feature images to construct the fingerprint database. To fully extract the signal features, a two-level hierarchical structure positioning system is proposed to achieve satisfactory positioning accuracy. A deep residual network (ResNet) rough locator is used to learn useful features from the wavelet feature fingerprint image database. Then, inspired by the transfer learning idea, a fine locator based on multilayer perceptron (MLP) is leveraged to further learn the features of the wavelet fingerprint image to obtain better localization performance. Additionally, multiple data enhancement techniques were adopted to increase the richness of the fingerprint dataset, thereby enhancing the robustness of the positioning system. Experimental results indicate that the proposed system leads to improved positioning performance in outdoor environments.

Wind speed is one of the important monitoring parameters to ensure mine safety. The commonly used mine wind speed sensor can be divided into ultrasonic type, impeller type and hot wire type according to the design principle. The accuracy of the latter two methods is not high enough because they are susceptible to steam and coal dust in mines. The ultrasonic wind speed sensor has better measuring accuracy. In this paper, ultrasonic wind speed sensor, ultrasonic sending and receiving circuit combined with ADC sampling function of the chip, to obtain the received ultrasonic amplitude change data, statistics of ultrasonic waveform changes caused by blowing, according to the number of changes in the wind speed frequency, and then calculate the real-time wind speed.

Background Breast cancer is the most frequently diagnosed malignancy among women and the second leading cause of cancer death worldwide. Among which nuclear estrogen receptor (nER) negative breast cancer is always with much poor prognosis. Recently, membrane G protein coupled estrogen receptor (GPER), a newly recognized estrogen receptor has been documented to take essential part in the development and treatment of breast cancer. The present study was designed to investigate the anti nER negative breast cancer effect of cryptotanshinone (CPT), an important active compound of traditional Chinese medicine Danshen and its possible molecular pathway. Methods The following in vitro tests were performed in nER negative but GPER positive breast cancer SKBR-3 cells. The effect of CPT on cell proliferation rate and cell cycle distribution was evaluated by MTT cell viability test and flow cytometry assay respectively. The role of PI3K/AKT pathway and the mediated function of GPER were tested by western blot and immunofluorescence. Technique of gene silence and the specific GPER agonist G-1 and antagonist G-15 were employed in the experiments to further verify the function of GPER in mediating the anticancer role of CPT. Results The results showed that proliferation of SKBR-3 cells could be blocked by CPT in a time and dose dependent manner. CPT could also exert antiproliferative activities by arresting cell cycle progression in G1 phase and down regulating the expression level of cyclin A, cyclin B, cyclin D and cyclin-dependent kinase 2 (CDK2). The antiproliferative effect of CPT was further enhanced by G-1 and attenuated by G-15. Results of western blot and immunofluorescence showed that expression of PI3K and p-AKT could be downregulated by CPT and such effects were mediated by GPER which were further demonstrated by gene silence test. Conclusion The current study showed that the antiproliferative action of CPT on SKBR-3 cells was realized by inhibition of GPER mediated PI3K/AKT pathway. These findings provide further validation of GPER serving as useful therapeutic target.

To investigate if steady-state resonant solution exist for any system of weakly interacting waves in a dispersive medium, a trio is considered in the Bretherton equation based on the homotopy analysis method (HAM). Time-independent spectrum was found when all components were travelling in the same direction. Within the trio, the amplitude of longer component is larger than that of shorter one. As the difference of wave number between components in trio increases or the nonlinearity of whole system increases, the amplitudes of all components tends to increase simultaneously. These findings are helpful to enrich and deepen our understanding about resonant solutions in any dispersive medium, especially for a two-dimensional scenario.

The PaaS platform based on cloud computing technology provides a large number of professional and flexible services in the fields of intelligent voice and computer vision. The large-scale application of 5G technology enables the software and hardware of the Internet of Things to use the PaaS service to improve the intelligence level of the system and reduce development costs. However, the problem of service invocation and service selection in the process of combining the IoT system with multiple PaaS platforms directly affects the interaction between the IoT perception layer and the application layer. This paper proposes a 5G multi-PaaS-oriented IoT dual middleware model. The unified communication protocol DMCP is designed. DMCP implements unified parsing of messages based on variable-length data items, which reduces the protocol conversion between the perception layer terminal device and multiple PaaS platforms. Complexity and high communication efficiency. Designed the PaaS service selection algorithm DMPS, DMPS comprehensively according to the equipment demand preferences and the overall performance of PaaS services, to achieve accurate service selection in the multi-PaaS platform at the application layer. Finally, examples and comparative tests verify the feasibility and effectiveness of the proposed model, protocol and algorithm.

Ubiquitous power Internet of things is an important direction of the development of smart grid, and distribution Internet of things is the application of ubiquitous power Internet of things in the field of distribution. As the terminal unit of state perception, intelligent decision-making and control subject in the distribution Internet of things, intelligent distribution and transformation terminal is the foundation to realize the distribution Internet of things. In order to solve the problems of complex software architecture of traditional distribution and transformation terminal, which is not conducive to expansion, maintenance and transplantation, Microservice + container technology is adopted as the software architecture of intelligent distribution and transformation terminal, which reduces the complexity of development, improves the efficiency of operation and maintenance, and meets the diverse and rapidly changing service requirements of distribution network.

Critical nodes have global significance for the network, the existing methods on the identification of critical nodes in Ad-hoc network usually based on the premise of topology is known, considering that there exists a link if the two nodes are in the other’s communication range, so the topology we get at last is relatively complex, but there are many links that aren’t exist in real which leading the identification of critical nodes with deviation. For this problem, in the paper we used Delaunay triangulation to optimize the network topology, based on identifying virtual backbone nodes by the unified connected dominating set, we measured the importance of the nodes by the average betweenness centrality. Experimental results show that the method proposed can identify the critical nodes in Ad-hoc networks effectively.

In this paper, a novel lost packets recovery scheme which encrypts the effective parts of an original packet into two shadow packets based on (2, 2)-threshold XOR-based visual Secret Sharing (VSS) is proposed. The two shadow packets used as watermarks would be embedded into two normal data packets with digital watermarking embedding technology and then sent from one sensor node to another. Each shadow packet would reveal no information of the original packet, which can improve the security of original packet delivery greatly. The two shadow packets which can be extracted from the received two normal data packets delivered from a sensor node can recover the original packet lossless based on XOR-based VSS. The Performance analysis present that the proposed scheme provides essential services as long as possible in the presence of selective forwarding attack. The proposed scheme would not increase the amount of additional traffic, namely, lower energy consumption, which is suitable for Wireless Sensor Network...

Antioxidant action is critical for maintaining the normal cardiovascular function and vascular endothelial cell is an important target of estrogen action through estrogen receptor (ER) pathway. This study is carried out to explore the antioxidant effect of carnosol in bovine aortic endothelial cells (BAECs) via ER pathway. The ER subtype specific estrogenic effect of carnosol was further demonstrated by luciferase reporter gene assay in human embryonic kidney (HEK) 293 cells. Carnosol was extracted from Chinese medicine Rosmarinus officinalis. ER positive BAECs were employed in cell proliferation assay and cell apoptosis tests. Oxidative stress by intracellular reactive oxygen species (ROS) were measured via 2'7'-dichlorofluorescein (DCF) production. ERα and ERβ specific antagonists 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy)phenol]-1H-pyrazole (MPP) and 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-yl]phenol (PHTPP) were employed as tools in the experiment. ER negative HEK 293 cells were employed in luciferase reporter gene assay. The results indicate that carnosol can effectively attenuate H(2)O(2) induced slowing down of cell growth and increasing of cell apoptosis. At the meantime, carnosol pretreating can also effectively reduce the H(2)O(2) induced intracellular ROS elevation in BAECs. ERα and ERβ antagonist, especially ERα antagonist, can effectively decrease the above antioxidant effects of carnosol. The reporter gene analysis further demonstrates that the action of carnosol on inducing ERE dependent luciferase expression is realized via ER pathway. The conclusion is that carnosol can exert antioxidant effects towards oxidative stress induced by H(2)O(2) in BAECs. And such effects are realized via ER, especially ERα pathway. The results contribute to explain the mechanism of cardiovascular protective function of carnosol in postmenopausal women.

In order to obtain optimum decision making in selecting main diesel engine for ships, the life cycle cost technology is proposed. The breakdown structure and calculation model of life cycle cost for main diesel engine of ships are established. Taking a specific selection for main diesel engine of one ship as the instance, the purchase cost and life cycle cost for three types of main diesel engine are compared and analyzed. The type of main diesel engine is selected based on the calculation result of life cycle cost. The instance shows that the life cycle cost technology is a powerful decision-making tool, which is worthy of popularization and application in ship design and development stages.

Antioxidant action is critical for maintaining the normal cardiovascular function and vascular endothelial cell is an important target of estrogen action through estrogen receptor (ER) pathway. This study is carried out to explore the antioxidant effect of carnosol in bovine aortic endothelial cells (BAECs) via ER pathway. The ER subtype specific estrogenic effect of carnosol was further demonstrated by luciferase reporter gene assay in human embryonic kidney (HEK) 293 cells. Carnosol was extracted from Chinese medicine Rosmarinus officinalis. ER positive BAECs were employed in cell proliferation assay and cell apoptosis tests. Oxidative stress by intracellular reactive oxygen species (ROS) were measured via 2'7'-dichlorofluorescein (DCF) production. ERα and ERβ specific antagonists 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy)phenol]-1H-pyrazole (MPP) and 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-yl]phenol (PHTPP) were employed as tools in the experiment. ER negative HEK 293 cells were employed in luciferase reporter gene assay. The results indicate that carnosol can effectively attenuate H(2)O(2) induced slowing down of cell growth and increasing of cell apoptosis. At the meantime, carnosol pretreating can also effectively reduce the H(2)O(2) induced intracellular ROS elevation in BAECs. ERα and ERβ antagonist, especially ERα antagonist, can effectively decrease the above antioxidant effects of carnosol. The reporter gene analysis further demonstrates that the action of carnosol on inducing ERE dependent luciferase expression is realized via ER pathway. The conclusion is that carnosol can exert antioxidant effects towards oxidative stress induced by H(2)O(2) in BAECs. And such effects are realized via ER, especially ERα pathway. The results contribute to explain the mechanism of cardiovascular protective function of carnosol in postmenopausal women.

Gamma-glutamyl transpeptidase (γ-GTP) was localized in prenatal and neonatal rat kidneys using an immunohistochemical method with monoclonal antibodies to rat kidney γ-GTP. γ-GTP was demonstrated on the brush border and basolateral membrane of proximal convoluted tubules from the 18th fetal day. The basolateral membrane of proximal tubules revealed strong reaction at 1 and 3 days after birth. The reaction of basolateral membrane decreased with the maturation of nephrons, however, moderate reaction was still observed at 30 days of age in the S3 segment. Throughout the postnatal development of the kidney, the S3 exhibited the strongest immunostainingand S1 showed the weakest reaction, and proximal tubules in the deep layer of the cortex always provided a stronger reaction than those in the superficial layer of the cortex. Maturating cuboidal and squamous epithelial cells of descending Henle's loop showed a positive reaction on the luminal and lateral cell membranes. On immunoelectron microscopy, γ-GTP was found on the brush border, basolateral membrane, membranes of pinocytotic vesicles and apical invaginations in proximal tubular cells at 1-7 days after birth. However, tight junctions were devoid of the reaction. The development of basal infolding and localization of γ-GTP there seemed to relate closely to the development of surrounding capillaries. γ-GTP was localized on the cell membrane and occasionally in the cytoplasm of interstitial cells of renal interstitium.

AIM: To study the role of hepatic sinusoidal capillarization and perisinusoidal fibrosis in rats with alcohol-induced portal hypertension and to discuss the pathological mechanisms of alcohol-induced hepatic portal hypertension. METHODS: Fifty SD rats were divided into control group (n=20) and model group (n=30). Alcoholic liver fibrosis rat model was induced by intragastric infusion of a mixture containing alcohol, corn oil and pyrazole (1 000:250:3). Fifteen rats in each group were killed at wk 16. The diameter and pressure of portal vein were measured. Plasma hyaluronic acid (HA), type IV collagen (CoIV) and laminin (LN) were determined by radioimmunoassay. Liver tissue was fixed in formalin (10%) and 6-μm thick sections were routinely stained with Mallory and Sirius Red. Liver tissue was treated with rabbit polyclonal antibody against LN and ColIV. Hepatic non-parenchymal cells were isolated, total protein was extracted and separated by SDS-PAGE. MMP-2 and TIMP-1 protein expression was estimated by Western blotting. RESULTS: The diameter (2.207 ± 0.096 vs 1.528 ± 0.054 mm, P

AIM: To study the effects of Radix Puerariae flavones (RPF) on liver lipid metabolism in ovariectomized (OVX) rats. METHODS: Forty adult female Wistar rats were randomly divided into four groups: OVX group; sham-OVX group; OVX + estrogen group and OVX + RPF group. One week after operation rats of the first two groups were treated with physiological saline, rats of OVX + estrogen group with estrogen (1 mg/kg·b.w.) and rats of OVX + RPF group with RPF (100 mg/kg·b.w.), respectively for 5 weeks. After the rats were killed, their body weight, the weight of the abdominal fat and uterus were measured, and the levels of total cholesterol (TC) and triglyceride (TG) in liver homogenate were determined. RESULTS: Compared with the sham-OVX group, the body mass of the rats in OVX group was found increased significantly; more abdominal fat in store; TC and TG in liver increased and uterine became further atrophy. As a result, the RPF was found to have an inhibitive action on those changes of various degrees. CONCLUSION: RPF has estrogen-like effect on lipid metabolism in liver and adipose tissue.

AIM: To observe the effect of compound Biejiaruangan decoction (CBJRGC) (composite prescription of Carapax trionycis for softening the liver) on proliferation, activation, excretion of collagen and cytokine of hepatic stellate cells (HSCs) and to find the mechanism of prevention and treatment of hepatic fibrosis by CBJRGC. METHODS: Using MTT, immunohistochemistry and image analysis technology, the related indexes for proliferation, activation, excretion of collagen and cytokine of hepatic stellate cells were detected in 24 h, 48 h, and 72 h after adminstration of different dosages of CBJRGC. RESULTS: Statistical analysis showed that serum collected from rat perfused with CBJRGC could restrain the proliferation of HSC in 48 h and 72 h especially in high and medium dosage groups, markedly decrease the expression of desmin, synapsin and platelet derived growth factor (PDGF) in HSC in 24 h, 48 h and 72 h, as well as the expression of α-SMA, collagen III, TIMP and TGFβ1 in 48 h and 72 h, decrease the excretion of collagen I in 72 h. CBJRGC serum had no significant effect on collagens I, III and TIMP in 24 h. CONCLUSION: CBJRGC serum has a good curative effect on hepatic fibrosis. Its main mechanism may be related to the following factors. The drug serum can restrain the proliferation and activation of HSC, decrease the number of activated HSC and the total number of HSC, the excretion of collagens I, III, enhance the degradation of collagen and restore the balance of synthesis and degradation of collagen, inhibit the expression of transforming growth factor β1 (TGFβ1) and platelet derived growth factor (PDGF) in HSC, block and delay the process of hepatic fibrosis. Synapsin is a new marker of activation of HSC, which provides a theoretical and testing basis for neural regulation in the developing process of hepatic fibrosis.