Periodontal condition in rats with experimental diabetes mellitus after orthodontic surgery

Background. Determine periodontal condition in rats with experimental diabetes mellitus after orthodontic surgery. Methods. In rats, type 1 diabetes mellitus (DM1) was reproduced with aloxane (100 mg / kg, intraperitoneally) once. Orthodontic surgery was performed by fixing the spring, starting from the 12th day. Animal euthanasia was performed on the 35th day of the experiment. The activity of urease, lysozyme, catalase, elastase, as well as the content of malondialdehyde (MDA) and hyaluronic acid were determined in the gum homogenate. In the alveolar bone homogenate, the activity of alkaline phosphatase (AlP) and acid phosphatase (AcP) and elastase was determined, as well as the content of calcium and protein. The antioxidant-prooxidant index (API) was calculated by the ratio of catalase activity and MDA content, and the degree of dysbiosis according to A. P. Levitsky was calculated by the ratio of the relative activities of urease and lysozyme. The mineralizing activity (MA) was calculated by the ratio of the activity of alkaline phosphatase (AlP) and AcP in the bone tissue and the mineralization (MD) degree was calculated by the ratio of the concentration of calcium, and protein. Results. In rats with DM1, the level of elastase, urease, MDA and the degree of dysbiosis increase in the gum, however, the level of lysozyme, hyaluronic acid, and the API index decrease. In the bone tissue of the periodontium of rats with type 1 diabetes, the level of alkaline phosphatase and MA decreases, but the level of AC increases. Orthodontic surgery significantly reduces the degree of dysbiosis in the gums and shows a tendency to increase API and decrease elastase activity. After orthodontic surgery, rats significantly increase the level of alkaline phosphatase and MA. Conclusion. With type 1 diabetes, periodontitis, dysbiosis develops and the mineralizing activity of periodontal bone tissue decreases. Orthodontic surgery tends to improve periodontal conditions

Ultra Reliable UAV Communication Using Altitude and Cooperation Diversity

The use of unmanned aerial vehicles (UAVs) that serve as aerial base stations is expected to become predominant in the next decade. However, in order for this technology to unfold its full potential it is necessary to develop a fundamental understanding of the distinctive features of air-to-ground (A2G) links. As a contribution in this direction, this paper proposes a generic framework for the analysis and optimization of the A2G systems. In contrast to the existing literature, this framework incorporates both height-dependent path loss exponent and small-scale fading, and unifies a widely used ground-to-ground channel model with that of A2G for analysis of large-scale wireless networks. We derive analytical expressions for the optimal UAV height that minimizes the outage probability of a given A2G link. Moreover, our framework allows us to derive a height-dependent closed-form expression and a tight lower bound for the outage probability of an \textit{A2G cooperative communication} network. Our results suggest that the optimal location of the UAVs with respect to the ground nodes does not change by the inclusion of ground relays. This enables interesting insights in the deployment of future A2G networks, as the system reliability could be adjusted dynamically by adding relaying nodes without requiring changes in the position of the corresponding UAVs

Reducing Consumed Energy while Drilling an Oil Well through a Deep Rig Time Analysis

As time goes by, increase in world energy demand forces oil and gas companies to drill deeper in order to produce more oil and gas for balancing world’s offer and demand. This requires drilling layers with various characteristics and dealing with more drilling problems as drilling progresses. Reduction of drilling problems can help drillers to reduce their cost effectively. Rig time break down of more than 300 wells in one south west Iranian oil field has been analysed to determine effective parameters on non-productive time amount. Results show that the most common drilling problems always have been experienced by drilling engineers are Equipment failure, stuck pipe and lost circulation which expose huge expenses to the oil companies. Several factors while drilling will govern how severe mud loss and stuck pipe would occur. These actually make analytical modelling of lost circulation or pipe sticking to somehow complicated. Hereby, employing artificial intelligence can be a leeway with proven capability and accuracy. In this research, operational parameters in Maroun oilfields are introduced to artificial neural networks to predict lost circulation severity, stuck pipe position and stuck pipe severity before happening. Results are well-matched with reality. Key words: Energy; Drilling problems; Lost circulation; Stuck pipe; Rig time analysi

Traumatic Endothelial Corneal Rings

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Optimal Recloser Setting, Considering Reliability and Power Quality in Distribution Networks

International audienceReclosers and fuses are the commonplace protective devices in distribution networks. A recloser can prevent long-time outages by clearing temporary faults before operation of the fuses in the system. Thus, it decreases the rate of long-term outages and improves system reliability and power quality. Despite positive features of reclosers, each operation of a recloser causes a momentary voltage interruption that exacerbates power quality. Nowadays, power quality issues have become more important because of the increasing use of sensitive equipment to voltage interruptions. According to the mentioned concerns, it seems necessary to set reclosers to strike a balance between power quality and the effectiveness of fuse saving scheme. Thus, we proposed a method to set reclosers. Due to the random nature of faults, the proposed method is stochastic based on the Monte Carlo method. The proposed method determines the optimal number of operations, reclosing intervals, and protection zones. The proposed method efficiency is evaluated according to the simulation results, and the proposed method is capable of establishing an optimal trade-off between power quality and protection efficiency