16 research outputs found
Microanatomic Morphometric Characteristics of the Third Ventricle Floor
Background: Endoscopic third ventriculostomy (ETV) is an effective treatment for hydrocephalus. The in-depth understanding of microanatomy is essential for accurate diagnosis, treatment and complications prevention. The aim of this study is to supplement the knowledge gap regarding the microanatomical metrics and correlations for which the literature includes only scarce mentions at best. Methods: This is a descriptive microanatomical study including 25 cadaver brains. Specimens from donors with neurological, psychiatric disorders or alcohol abuse were excluded. Surgical loops were used for harvesting. High-precision tools were employed to dissect and measure the anatomical landmarks under a surgical microscope. Each measurement was performed in three consecutive attempts and outliers were rejected. RStudio was used for statistical analysis. Distribution was evaluated employing the Shapiro–Wilk test. Normally distributed values were presented as mean and standard deviation, and others as median and interquartile range. Results: The age of the donors was 61.72 (±10.08) years. The distance from the anterior aspect of the foramen of Monro to the anterior margin of the mamillary body was 16.83 (±1.04) mm, and to the posterior margin was 16.76 (±1.9) mm. The distance from the anterior mamillary body margin to the infundibulum was 6.39 (±1.9) mm, to the optic recess was 8.25 (±1.84) mm, and to the apex of the vertebral artery was 5.05 (±1.62) mm. The distance from the anterior commissure to the brain aqueduct was 22.46 (±2.29) mm, and to the infundibulum was 13.93 (±2.54) mm. The mamillary body diameter was 4.91 (±0.34) mm in the anteroposterior and 4.21 (±0.48) mm in the cranio-caudal plane. The intraventricular segment was protruding by 1.63 (±0.46) mm. The diameter of the hypothalamus on the anterior margin of mamillary bodies was 1.37 (±0.75) mm, of the Liliequist membrane was 0.19 (±0.07) mm and of the lamina terminalis was 0.35 (±0.32) mm. Conclusion: The presented microanatomical measurements and correlations are expected to contribute to the improvement of ETV safety
Testing and analysis of a dual-tube latent heat storage system
In order to effectively charge and discharge a latent heat thermal energy storage (LH-TES), a driving temperature difference between charging and discharging needs to exist, resulting in a higher charging than discharging temperature. A dual-tube LH-TES concept was developed in order to make this possible using different media or process parameters in separated tubes without the need for expensive valves and control systems. A storage unit was designed, tested and built using two different refrigerants in the respective charging and discharging processes, showing the feasibility of such a system. An axially finned tube was designed to be assembled on tubepairs, allowing for heat conduction via highly conductive aluminum directly between the circuits, as well as heat transfer between the heat transfer fluid and the phase change storage material. Data from the experimental analysis will be shown and discusse
Socially Aware Heterogeneous Wireless Networks
The development of smart cities has been the epicentre of many researchers’ efforts during the past decade. One of the key requirements for smart city networks is mobility and this is the reason stable, reliable and high-quality wireless communications are needed in order to connect people and devices. Most research efforts so far, have used different kinds of wireless and sensor networks, making interoperability rather difficult to accomplish in smart cities. One common solution proposed in the recent literature is the use of software defined networks (SDNs), in order to enhance interoperability among the various heterogeneous wireless networks. In addition, SDNs can take advantage of the data retrieved from available sensors and use them as part of the intelligent decision making process contacted during the resource allocation procedure. In this paper, we propose an architecture combining heterogeneous wireless networks with social networks using SDNs. Specifically, we exploit the information retrieved from location based social networks regarding users’ locations and we attempt to predict areas that will be crowded by using specially-designed machine learning techniques. By recognizing possible crowded areas, we can provide mobile operators with recommendations about areas requiring datacell activation or deactivation
Error Control Schemes in Wireless Broadband Networks
Abstract-- With rapid advances in wireless packet networking technology, it is becoming possible to provide mobile users not only with data, voice, but also with various communication services. In order to provide these services to mobile users /terminals, it is necessary to have not only sufficient bandwidth for support of high speed transmission, but also effective control over wireless channel errors. Forward error correction coding (FEC) is a widely used method to improve transmission quality in wireless broadband communication systems. In this paper, we present and evaluate three Error Control algorithms in broadband wireless networks and we discuss methods for comparing the performance of codes of various convolutional codes and Reed-Solomon codes