UAV-Assisted Low-Consumption Time Synchronization Utilizing Cross-Technology Communication.

Wireless sensor networks (WSNs) have been used in many fields due to its wide applicability. In this kind of network, each node is independent of each other and has its own local clock and communicates wirelessly. Time synchronization plays a vital role in WSNs and it can ensure accuracy requirements for coordination and data reliability. However, two key challenges exist in large-scale WSNs that are severe resource constraints overhead and multihop time synchronization errors. To address these issues, this paper proposes a novel unmanned aerial vehicle (UAV)-assisted low-consumption time synchronization algorithm based on cross-technology communication (CTC) for a large-scale WSN. This algorithm uses a UAV to send time synchronization data packets for calibration. Moreover, to ensure coverage and a high success rate for UAV data transmission, we use CTC for time synchronization. Without any relays, a high-power time synchronization packet can be sent by a UAV to achieve the time synchronization of low-power sensors. This algorithm can achieve accurate time synchronization with almost zero energy consumption for the sensor nodes. Finally, we implemented our algorithm with 30 low-power RF-CC2430 ZigBee nodes and a Da Jiang Innovations (DJI) M100 UAV on a 1 km highway and an indoor site. The results show that time synchronization can be achieved accurately with almost zero energy consumption for the sensor nodes, and the time synchronization error is less than 30 µs in 99% of cases.

A Novel Mine Cage Safety Monitoring Algorithm Utilizing Visible Light.

The mine cage has an important role in the production of coal mines. It has many safety problems in the transportation of people, such as overloading of personnel and illegal outreach of human limbs. However, the harsh mine environment makes it very difficult to monitor personnel overload and limb extension. To solve these two problems, we propose a novel safety monitoring algorithm of the mine cage based on visible light. With visible light technology, our algorithm cleverly utilizes the existing underground lighting equipment (i.e., miner's headlamp and the miner's lamp deployed on the mine cage) as the transmitter to broadcast the light beacons representing unique identity information through visible light frequency modulation. Next, cheap photodiodes deployed in the mine cage are used as the receiver to perceive the modulated optical signals. Then we use the frequency matching method for personnel counting and the frequency power comparison method for illegal limb extension monitoring. Moreover, a novel method of monitoring the delineated safe area of the mine cage is also proposed to ensure that all the miners are in the delineated safe area. Finally, we conducted extensive experiments with a simulated mine cage model. Results show that our algorithm has superior performance. With the photodiode SD5421-002, the accuracy of personnel overload judgment and safe area monitoring of our algorithm can reach 99%, and the accuracy of limb extension monitoring is more than 96%.

ARS: Adaptive Robust Synchronization for Underground Coal Wireless Internet of Things.

Clock synchronization is still a vital and challenging task for underground coal wireless internet of things (IoT) due to the uncertainty of underground environment and unreliability of communication links. Instead of considering on-demand driven clock synchronization, this paper proposes a novel Adaptive Robust Synchronization (ARS) scheme with packets loss for mine wireless environment. A clock synchronization framework that is based on Kalman filtering is first proposed, which can adaptively adjust the sampling period of each clock and reduce the communication overhead in single-hop networks. The proposed scheme also solves the problem of outliers in data packets with time-stamps. In addition, this paper extends the ARS algorithm to multi-hop networks. Additionally, the upper and lower bounds of error covariance expectation are analyzed in the case of incomplete measurement. Extensive simulations are conducted in order to evaluate the performance. In the simulation environment, the clock accuracy of ARS algorithm is improved by 7.85% when compared with previous studies for single-hop networks. For multi-hop networks, the proposed scheme improves the accuracy by 12.56%. The results show that the proposed algorithm has high scalability, robustness, and accuracy, and can quickly adapt to different clock accuracy requirements.

Intracranial Enterogenous Cysts Close to the Brainstem Treated Through the Nerve Endoscope.

Enterogenous cysts (ECs) are rare, inborn lesions of central nervous system, which mostly occurred in the ventral side of the spinal cord as well as common in children; adult intracranial cysts are rare. Although the morbidity of intracranial ECs is quite low, we also can make a preliminary diagnosis of those patients with the help of imaging examination. In this article, we introduced 1 case of ECs ventral to the brainstem, which present images on magnetic resonance imaging as hypointense lesions on T1-weighted and high-intensity mass on T2-weighted image. In consideration of the difficulty of the surgical approach and the surgical visual field exposure, we use microscope and nerve endoscope to design personalized surgical approach to minimize the surgical injury. Pathologic examination showed that it was typical EC. Not only is the location extremely rare, but also the surgical method is uncommon in this disease. We not only study the intracranial ECs' manifestations, but also discuss the surgical approach and the application of nerve endoscope of our choice,which aims to provides a new surgical therapeutic approach for these lesions.

Long non­coding RNA SNHG16 inhibits the oxygen­glucose deprivation and reoxygenation­induced apoptosis in human brain microvascular endothelial cells by regulating miR­15a­5p/bcl­2.

MicroRNA (miR) 15a­5p can promote ischemia/reperfusion (I/R)­induced apoptosis of cerebral vascular endothelial cells, which is inhibited by long non­coding RNAs (lncRNAs). The present study investigated the potential of lncRNAs targeting miR­15a­5p to regulate oxygen­glucose deprivation and reoxygenation (OGD­R)­induced apoptosis of human brain microvascular endothelial cells (hBMECs). hBMECs were transfected with or without miR­15a­5p or its mutant, together with p­small nucleolar RNA host gene 16 (SNHG16) or its mutant. Following OGD­R, proliferation, apoptosis and miR­15a­5p, SNHG16 and Bcl­2 expression levels were determined using MTT, flow cytometry, reverse transcription­quantitative PCR or western blotting. The potential interaction of SNHG16 with miR­15a­5p was analyzed by pull­down, luciferase and immunoprecipitation assays. OGD­R induced apoptosis of hBMECs and increased miR­15a­5p expression levels in a time­dependent manner. miR­15a­5p overexpression decreased the proliferation of hBMECs and promoted apoptosis by decreasing Bcl­2 expression levels. SNHG16 was pulled­down by miR­15a­5p and anti­Ago2. miR­15a­5p overexpression significantly decreased SNHG16­regulated luciferase activity and hBMEC survival by increasing apoptosis. SNHG16 overexpression decreased miR­15a­5p expression levels in hBMECs. SNHG16 gradually decreased following OGD­R and its overexpression decreased miR­15a­5p expression levels and promoted the proliferation of hBMECs by decreasing apoptosis. SNHG16 enhanced Bcl­2 expression levels in hBMECs, which was abrogated by miR­15a­5p. Bioinformatics suggest that SNHG16 may antagonize the binding of miR­15a­5p to the 3'UTR of Bcl­2 mRNA. These findings suggest that SNHG16 may protect hBMECs from OGD­R­induced apoptosis by antagonizing the miR­15a­5p/bcl­2 axis. Thus, targeting SNHG16­based mechanisms may provide novel therapeutic strategies for treatment of ischemic stroke.

[Optimization of a novel mucoadhesive drug deliver system with ion-exchange resin core loaded with berberine hydrochloride using central composite design methodology].

A novel mucoadhesive microcapsule with drug-resin complex core loaded with berberine hydrochloride (BH) was developed and optimized. Drug-ion exchange resin (IER) complex was prepared by static method which stirring IER in drug solution at certain conditions. The influences of different IERs, different temperature, pH values and concentrations of drug solution on the drug loading were investigated. IER complex was coated by emulsion-solvent evaporation method. The coating fluid formulation was optimized using central composite design-response surface methodology, where the ratio between Carbopol 934 and IER (X1), the ratio between Eudragit and IER (X2) and the ratio between Eudragit RL and RS (X3) were taken as independent variables. Time of cumulative release 85% (Y1) and percentage of gastric retention (Y2) were taken as response variables. Drug loading achieved a high level and more drug available in the condition of IER (IRP 88), 37 degrees C, pH 5 and 1.0 mg x mL(-1) drug solution. When X1 = 0.75, X2 = 0.9, X3 = 0.6, the time of cumulative release reached 85% at 300 min, the highest percentage of gastric retention in the range of this experiment were procured.

Moesin Expression Is Associated with Glioblastoma Cell Proliferation and Invasion.

AIM: To investigate the effect of moesin expression on cell proliferaton and invasion of human glioblastoma cell lines in vitro. MATERIALS AND METHODS: Glioblastoma LN229 and U87 cells were transfected with the H4645-plenti-EGFP-moesin expression vector for moesin up-regulation. Moesin and ß-catenin expression levels in the transfected cells were analyzed by real-time polymerase chain reaction (PCR) and Western blotting. Cell proliferation was measured using the CCK8 assay. Cell invasion and migration ability were assessed using a transwell cell invasion and wound-healing assay. RESULTS: Moesin mRNA and protein expression were significantly increased in the two transfected LN229-H4645 and U87-H4645 cell lines. ß-catenin expression was increased by moesin up-regulation in the transfected LN229-H4645 and U87-H4645 cell lines. The CCK-8 assay revealed that up-regulating moesin results in a significant increase in glioblastoma cell proliferation. Glioblastoma cell invasion and migration were increased by moesin up-regulation. CONCLUSION: Up-regulation of moesin expression in glioblastoma cells correlated with increases in cell proliferation, invasion and migration, suggesting moesin's role in glioblastoma progression.