Orientation and Depth Control in Rippling Water for an Autonomous Underwater Robot

This paper describes an algorithmic solution for simple and efficient underwater orientation and depth control. Maintaining a position with an underwater robot is a difficult task. In the case of an Autonomous Underwater Vehicles (AUVs), not only the underwater conditions, but also the environmental effects off the surface need to be considered. There are a large number of algorithms have been designed by researchers based on computer vision, sensor fusion, etc. to estimate the location precisely, yet most of them are specific for the given hardware. Our solution employs a multi-sensor fusion based algorithm, where the data is taken from magnetic and pressure sensors. A PID controller was designed and implemented to ensure proper orientation keeping and depth control in rippling water. The solution has been tested in various environments, and successfully used during the marine challenges of the euRathlon 2015 competition

Simplified coronary flow reserve calculations based on three-dimensional coronary reconstruction and intracoronary pressure data

Background: Measurements of fractional flow reserve (FFR) and/or coronary flow reserve (CFR) are widely used for hemodynamic characterization of coronary lesions. The frequent combination of the epicardial and microvascular disease may indicate a need for complex hemodynamic evaluation of coronary lesions. This study aims at validating the calculation of CFR based on a simple hemodynamic model to detailed computational fluid dynamics (CFD) analysis. Methods: Three-dimensional (3D) morphological data and pressure values from FFR measurements were used to calculate the target vessel. Nine patients with one intermediate stenosis each, measured by pressure wire, were included in this study. Results: A correlation was found between the determined CFR from simple equations and from a steady flow simulation (r = 0.984, p < 10−5). There was a significant correlation between the CFR values calculated by transient and steady flow simulations (r = 0.94, p < 10−3). Conclusions: Feasibility was demonstrated of a simple hemodynamic calculation of CFR based on 3D-angiography and intracoronary pressure measurements. A simultaneous determination of both the FFR and CFR values provides the capability to diagnose microvascular dysfunction: the CFR/FFR ratio characterizes the microvascular reserve

Three-dimensional evaluation of the spatial morphology of stented coronary artery segments in relation to restenosis

To investigate the correlations between the three-dimensional (3D) parameters of target coronary artery segments and restenosis after stent implantation. Sixty-four patients after single, cobalt chromium platform stent (27 BM stents and 37 DES) implantation were investigated retrospectively 12 ± 6 months after the index procedure. 3D coronary artery reconstruction was performed before and after the stent implantation using appropriate projections by a dedicated reconstruction software. The curve of the target segment was characterized by the ratio of the vessel length measured at midline (arc: A) and the distance between the edge points of the stent (chord: C): A/C ratio (ACr). Age, diabetes and hyperlipidaemia were taken into account for the statistical evaluation. 22 patients were diagnosed with ISR, while 42 patients without any restenosis served as controls. The two groups did not differ regarding major cardiovascular risk factors, proportion of the treated vessels or the type of stents. Higher initial ACr values were associated with greater straightening of the vessel curvature in all groups (p < 0.001). Significant negative correlations were found in cases of proximal or distal edge bending angles (p < 0.001). Pre-stent edge bending angles < 7° often showed an increase after the stent implantation, while in case of higher initial values, the bending angles generally decreased. Using multivariate logistic regression modelling we found that the pre-stent ACr was an independent predictor of in-stent restenosis (odds ratio for 1% increase of the ACr: 1.08; p = 0.012). Changes of angles at the stent edges following stent implantation correlate with the initial local bending angles. The ACr predispose to chronic shear stress in the vessel wall, which may contribute to the pathological intimal proliferation

Three-dimensional evaluation of the spatial morphology of stented coronary artery segments in relation to restenosis

To investigate the correlations between the three-dimensional (3D) parameters of target coronary artery segments and restenosis after stent implantation. Sixty-four patients after single, cobalt chromium platform stent (27 BM stents and 37 DES) implantation were investigated retrospectively 12 ± 6 months after the index procedure. 3D coronary artery reconstruction was performed before and after the stent implantation using appropriate projections by a dedicated reconstruction software. The curve of the target segment was characterized by the ratio of the vessel length measured at midline (arc: A) and the distance between the edge points of the stent (chord: C): A/C ratio (ACr). Age, diabetes and hyperlipidaemia were taken into account for the statistical evaluation. 22 patients were diagnosed with ISR, while 42 patients without any restenosis served as controls. The two groups did not differ regarding major cardiovascular risk factors, proportion of the treated vessels or the type of stents. Higher initial ACr values were associated with greater straightening of the vessel curvature in all groups (p < 0.001). Significant negative correlations were found in cases of proximal or distal edge bending angles (p < 0.001). Pre-stent edge bending angles < 7° often showed an increase after the stent implantation, while in case of higher initial values, the bending angles generally decreased. Using multivariate logistic regression modelling we found that the pre-stent ACr was an independent predictor of in-stent restenosis (odds ratio for 1% increase of the ACr: 1.08; p = 0.012). Changes of angles at the stent edges following stent implantation correlate with the initial local bending angles. The ACr predispose to chronic shear stress in the vessel wall, which may contribute to the pathological intimal proliferation

Salivary IL-6 mRNA is a Robust Biomarker in Oral Squamous Cell Carcinoma

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Debrecen város ivóvizének minősége a Víz Keretirányelv tükrében

Dolgozatom során kiemelt szerepet kapott Debrecen város ivóvízellátásának bemutatása, az ivóvíz minőségre vonatkozó határozatok, jogszabályok ismertetése, valamint a megengedett ivóvíz minőségre irányuló határértékek feltüntetése. Munkám során összevetettem Debrecen város ivóvizének minőségét az Európai Unió által kötelező Víz Keretirányelv előírásaival. A VKI első periódusának kezdő évében, valamint a záró évében mért eredményeket hasonlítottam össze, figyeltem a VKI hatását és levontam a következtetéseket.BSc/BAKörnyezetgazdálkodási agrármérnö