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  • Author: István Kovács x
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Abstract

In this short survey and case study we want to present our research experience through the project developed by our team, that involves the building of a LEGO MINDSTORMS EV3 robotic arm and tracked robot car which mimics the motion of the human arm and legs. We used 3 interconnected LEGO MINDSTORMS EV3 bricks to reach the desired degrees of freedom. Using a Kinect sensor, the system detects the motion of the human user’s arm and creates the skeletal image of the arm. Coordinate geometry and different approximation methods are used to calculate the rotation angles between the bones connecting the joints. In our project the key is inverse kinematics, whitch makes use of the kinematics equations to determine the joint rotation parameters that provide a desired position for each of the robot’s end-effectors – arms and legs (wheels). The combined motion of the LEGO MINDSTORMS EV3 motors results in a complete robotic forward or backward motion and arm movement which is a perfect mimic of the human arm movement.

Abstract

Wood-burning power plants and heating plants produce a great amount of wood ash as a by-product of the combustion process. In 2009 we launched an experiment in which we examined the composition of ash, the nutrient supplying capacity of soil mixed with ash, and the availability of its constituents. In the spring of 2010, we conducted small plot experiments using wood ash applications equivalent to 0; 1; 2.5; 5 and 10 t of wood ash/ha, on slightly acidic clay loam soil using white mustard and rye grass as the test plants. The pH value of the soil rose in a statistically verifiable way as a result of the ash treatments. After the application of ash, the P2O5 and K2O-content of the soil rose significantly; the treatments also increased the magnesium and sulphur content of the arable soil as well as the level of Zinc among the microelements. However, none of the wood ash applications caused verifiable changes in the number of shoots, in the green mass, or in the height of test plants. The increased nutrient supply of the soil through the treatments was not reflected in the nutrient content of the plants during the first year.

Abstract

Research on ecosystem services and landscape functions are highly important in landscape ecology, landscape planning and open space design. The terms of ecosystem service and landscape function have been evolved parallel to each other in the scientific literature but have different focus. The term of landscape functions evolved from the scientific field of landscape ecology; it reflects the goods and services provided by regions, landscapes where the cultural, economic factors are important as well. As a framework assessment method with additional economic assessment, a landscape function analysis could be an additional tool of rural development, as it gives a complex analysis of multiple aspects, thus it is highly appropriate to explore, analyze the potentials, resources and limits of landscapes and land use systems. In the current research a landscape function analysis was compared with the rural development strategies in Hungarian micro-regions. We focused on the level of landscape functions and the objectives of the rural development strategies of the study areas. The local development strategies do not focus on territorial differences nor potentials evolving from natural, cultural resources or local constrains. The only exception is tourism development, where in some cases there is a holistic spatial approach which intends to develop the region as a whole.

Abstract

Introduction: The recent development of large networks dedicated to ST-segment elevation myocardial infarction (STEMI) led to a significant increase in the number of primary percutaneous interventions (p-PCI) parallel with mortality reduction in Acute Coronary Syndrome (ACS). The number of non ST segment elevation myocardial infarction (NSTEMI) is increasing and the highest mortality rates are encountered in patients with cardiogenic shock and/or out of hospital cardiac arrest associated to ACS. The aim of this study was to identify the factors associated with a higher mortality rate in a global population with acute coronary syndromes presented in the emergency department of a county clinical hospital which serves as a regional center for a STEMI network.

Material and method: This is a retrospective study including 684 patients with acute coronary syndrome admitted in the Clinic of Cardiology from the County Clinical Emergency Hospital Tîrgu Mureș in 2014. In all the cases, the factors that correlated with in hospital mortality were identified and analyzed.

Results: The incidence of arterial hypertension was significantly higher in patients admitted with unstable angina (75.0%) and STEMI cases with less than 12 hours onset of symptomatology (68.1%), while impaired renal function correlated with the presence of NSTEMI (66.6%). The presence of a multivessel disease was significantly correlated with cardiogenic shock. The localisation of the culprit lesion in the left anterior descending artery (LAD) significantly correlated with the development of cardiogenic shock, LAD culprit lesions being present in 44.4% of CS cases as compared with 21.7% of noCS cases in STEMI patients. In NSTEMI patients, the localisation of the culprit lesion in the left main artery (LM) significantly correlated with the development of cardiogenic shock, culprit lesions in the left main being present in 47.0% of CS cases as compared with 28.5% of noCS cases in STEMI patients.

Conclusion: Patients presenting with out-of-hospital resuscitated cardiac arrest due to Acute Myocardial Infarction associate higher in-hospital mortality rates. In-hospital mortality seems to be highly correlated with the female gender, STEMI myocardial infarction and the presence of multivascular lesions.

Abstract

Hematological conditions and their treatments have an increased risk of cardiovascular events, and invasive interventions have a higher risk of periprocedural complications in this group of patients. The aim of this review was to evaluate the risk of invasive interventions in patients with hematologic disorders and to underline the role of noninvasive cardiovascular screening in patients with hematological disorders such as Hodgkin and non-Hodgkin lymphoma, anemia, hemophilia, thrombocythemia, polycythemia vera, and leukemia. Based on present knowledge in the field, our opinion is that the screening of patients with hematological diseases is very important to reduce the morbidity and mortality due to cardiovascular events. Noninvasive assessments are suitable for this purpose with a significantly lower risk compared to invasive interventions.

Abstract

Introduction: Premature ventricular complex (PVC) is the most common cardiac arrhythmia, which in some circumstances can lead to syncope, arrhythmia-induced cardiomyopathy and sudden death. In idiopathic PVCs, the first choice of treatment is radio-frequency ablation. Identification of the substrate location makes it possible to determine the ablation site, leading to an increased success rate. Complications are related mainly to the ablation technique, peri-procedural anticoagulation therapy, and the access site. Pericardial tamponade is a rare complication. A case in which the ablation procedure of idiopathic PVCs, complicated by cardiac tamponade, is presented in this paper.

Case presentation: A 56-year-old female presented with symptomatic premature ventricular contractions. She had frequent palpitations, dyspnea, and exercise intolerance for ten years. Holter-monitoring demonstrated a total burden of 30,549 PVCs with monomorphic morphology, and with both bigeminal and trigeminal patterns. Surface ECG suggested a left-sided, left aortic cusp localization of the PVC, with a possible epicardial origin. Three-dimensional mapping was performed including the RVOT (right ventricular outflow tract) region, aorta, and coronary sinus. The ablation clinical status suggested a cardiac tamponade, which was confirmed by echocardiography. Radioscopy-controlled pericardial puncture was performed with the extraction of 300 ml of blood. Following this maneuver, the general status of the patient improved. During follow-up checks after twenty-four hours, Holter-monitoring recorded 5000 PVCs with a significant improvement in the clinical status of the patient.

Discussions: Pericardial tamponade after radio-frequency ablation is a rare complication. The risk of tamponade in a right chamber perforation is more dangerous in patients on anticoagulation therapy or with pulmonary hypertension. In order to prevent this side effect complication of the interventional procedures, certain safety maneuvers should be followed, including the use of irrigated-type catheters, or when possible, contact force catheters, ensuring invasive arterial blood pressure monitoring during intervention, and after heparin administration and the determination of ACT every twenty minutes. Transthoracic echocardiograph examination and pericardial puncture set should be readily available in the electrophysiology laboratory.

Abstract

Severe limb ischemia represents a critical condition, being associated with high morbidity and mortality rates. Patients with critical limb ischemia (CLI) require urgent initiation of interventional or surgical treatment, as restoration of the blood flow is the only way to ensure limb salvage in these critical cases. At the same time, in acute limb ischemia, a dramatic form of sudden arterial occlusion of the lower limbs, the integrity of the limb is also seriously threatened in the absence of urgent revascularization. From patients with CLI, 40% are “no option CLI”, meaning patients in whom, due to anatomical considerations or to the severity of the lesions, there is no possibility to perform interventional or surgical treatment or they have failed. Therapeutic angiogenesis has been proposed to serve as an effective and promising alternative therapy for patients with severe limb ischemia who do not have any other option for revascularization. This review aims to present the current status in therapeutic angiogenesis and the role of different approaches (gene or cell therapy, intra-arterial vs. intramuscular injections, different sources of cells) in increasing the rates of limb salvage in patients with severe ischemia of the lower limbs.

Abstract

Introduction: The location of culprit lesions on the left main is associated with an increased procedural risk in acute coronary syndromes. Our study aims to evaluate the utility of CT angiography determined Syntax score (CCTA) in comparison with the classical angiographic Syntax score for predicting the procedural success in percutaneous coronary interventions (PCI) of left main lesions.

Methods: We included 23 patients presenting to the Cardiology Clinic with an acute coronary syndrome. All patients underwent coronary angiography ± angio CT multisclice for assessment of the target lesion, defined as a significant (>50%) left main disease. Patient population consisted in: group 1 – 13 patients (56.52%), in whom revascularization indication was based on lesion severity assessment by CCTA score correlated with the angio Syntax score (SS), and group 2 – 10 patients (43.48%), in whom revascularization indication was based only on angio SS. According to the SS, the study population was divided into subgroup A – low SS (<22), subgroup B – intermediate SS (23–32) and subgroup C –high SS (>32). All patients were followed for 1 year.

Results: Despite similar SS in both groups (35.38 in group 1 vs. 32.4 in group 2), the use of Angio CT multislice increased the rate of PCI indication – 76.92% PCI in group 1 versus 50% PCI in group 2. In patients with high SS, PCI rate was 66.66% in group 1 compared with 50% in group 2 (p<0.05). High calcium score >100 was recorded in 50% of patients in the low SS subgroup (<22), 50% in the medium SS subgroup (23–32) and 22.22% in the high SS (>33) subgroup. One-year follow-up showed an overall mortality of 8.69%, slightly higher in group 2 (10%), as compared to group 1 (mortality of 7.69%).

Conclusions: Additional evaluation by angio CT of culprit left main stenoses in acute coronary syndromes provides more information about the complexity of atherosclerotic plaques in this location, and could be extremely useful in establishing the indication for PCI in high risk stenoses, showing a predictive significance for post-procedural 1 year follow up mortality.