Theses (Faculty of Science and Technology)
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A DE Természettudományi és Technológiai Kar Tanácsának 2009. november 25.-i határozata alapján a jövőben elektronikus formában is elhelyezésre kerülnek a szakdolgozatok a Debreceni Egyetem Egyetemi és Nemzeti Könyvtár által működtetett egyetemi archívumban, a DEAba. A szakdolgozatok az archívumból kizárólag a Debreceni Egyetem IP-címeiről hozzáférhetőek, azokat nem lehet kinyomtatni, és azokból szövegrészeket nem lehet kiemelni.
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Tétel Korlátozottan hozzáférhető A 10 Year Statistical Analysis of Heavy Metal in River and Sediment in River Tisza, HungaryBabar, Nayna; Czédli, Herta; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetIn course of our research, we did 10-year statistical analysis of heavy metals in Tisza river, Szolnok from 2010-2020. In doing so, we measured As, Zn, Hg, Cd, Cr, Mn, Ni, Pb, Cu, Fe from Tisza river. The sampling point was conducted at the Szolnok road bridge (335.5 TKM) from the small circle of the Tisza to the Hármas-Körös. The samples were collected from the period of 01/01/2010-03/12/2020. We did a time-series analysis on heavy metals.Tétel Korlátozottan hozzáférhető 15-membered rigid macrocyclic ligand for Mn2+ complexation: synthesis and coordination chemical characterizationBaghirova, Aghanana; Tircsó, Gyula; DE--Természettudományi és Technológiai Kar--Kémiai IntézetThe investigation of Mn²⁺ chelates as alternatives to Gd³⁺-based MRI contrast agents has gained significant attention due to their promising safety and performance profiles. My research focused on the synthesis and coordination chemistry of a novel 15-membered bipyridine-based macrocyclic ligand, 15-BPyN5. The ligand demonstrated excellent thermodynamic stability (log K_MnL = 13.44), high kinetic inertness, and favorable relaxivity properties (r1p/r2p = 3.60/6.60 mM⁻¹s⁻¹). Dissociation studies revealed slow exchange kinetics with Zn²⁺ ions, with half-lives of 79.0 and 28.7 hours at 25°C and 37°C, respectively, attributed to the rigid coordination environment provided by the bipyridine moiety. These properties highlight the potential of [Mn(15-BPyN5)] as a safe and effective MRI contrast agent. This work paves the way for developing non-toxic alternatives to gadolinium-based agents, offering improved safety and imaging performance.Tétel Korlátozottan hozzáférhető 2024 Update of Retro-Transposons in the Aspergillus and Penicillium Genera and Other Filamentous FungiAdil, Dastan; Michel , Flipphi; Michel , Flipphi; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetRetrotransposons are mobile genetic elements that can generate genomic diversity, impacting gene expression and genomic stability. This thesis investigates the role of Copia-type retrotransposons, specifically Ty1 elements, in filamentous fungi like Aspergillus niger and Penicillium chrysogenum, focusing on their evolutionary and biotechnological significance. The study examines the structural characteristics, integration patterns, and functional impacts of AniTA2, a Copia retrotransposon identified in A. niger, with attention to its influence on genes linked to industrially relevant traits. Further, it discusses the application of Ty1 retrotransposons in industrial strain development, highlighting both their potential to enhance fungal strains and the challenges posed by genomic instability. The research concludes with future possibilities for using genome-editing tools like CRISPR/Cas9 to harness Ty1 elements safely for fungal biotechnology.Tétel Korlátozottan hozzáférhető 33 MVA DISTRIBUTION GRID FOR A NIGERIAN TOWNSHIP USING MEDIUM VOLTAGEMaduagwu, Osinaka; Kosa, Janos; DE--Természettudományi és Technológiai Kar--Fizikai IntézetThe power sector is the backbone of any thriving economy, providing the necessary energy for industrial, commercial, and domestic activities. In Nigeria, as in many developing nations, the power sector has been marred by persistent challenges, hindering the nation's economic growth and development. This dissertation seeks to delve into the intricate workings of the 33 MVA distribution grid in Nigeria, examining its role in the broader context of the nation's power sector, and proposing strategic interventions to address the prevailing issues. Nigeria, with its rapidly growing population and expanding economy, faces a continuous struggle to meet the escalating demand for electricity. The 33 MVA distribution grid plays a pivotal role in the final stage of the power supply chain, distributing electricity to end-users across various regions. However, despite the significance of this grid, there are systemic challenges that have hampered its effectiveness. In this report we are going to have an overview of how I conducted my thesis research report with the help of my supervisor Dr János Kosa. In my research report, we divided it into five main segments of which I wrote a detailed description of each segment to give an idea of what we are working with and how it all builds up together eventually. The following are the five main segments are listed below: 1. Show the Nigerian power grids. 2. Direction of development in Nigeria. 3. Design a medium voltage grid. 4. Calculation of the grid. 5. Applied switch gears in planned system.Tétel Korlátozottan hozzáférhető A FIRST STEP IN ASSESSING THE DIATOM-BASED ECOLOGICAL STATUS OF INTERMITTENT STREAMS IN THE CARPATHIAN BASINESTHER, SHAMIM; Edina Kundrát-Simon, Viktória B-Béres; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetExtreme weather events such as prolonged droughts or flash floods are currently the most obvious signs of climate change. These disturbances are causing significant environmental stress to the wetland and aquatic communities. In the last century, the average temperature in the Carpathian Basin has increased by approximately 1°C. All of these alterations had a significant impact on the small streams, resulting in a typological shift in many of them: streams that had a permanent water supply became intermittent waters. In recent years, our research group has been studying the effects of stream drying on benthic algal assemblages in small watercourses in the Carpathian Basin. Here, we focus on the differences in diatom indices between (i) intermittent and permanent lowland streams and (ii) different phases of drying such as flowing, standing and dry phasesTétel Korlátozottan hozzáférhető A Novel Approach Utilizing Polylactic Acid and Chitosan for Enhanced Shelf Life and Sustainability.Uurtsaikh, Tselmegzaya; Norbert , Ág; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetBiopolymers, such as chitosan and polylactic acid (PLA), are being thought of more and more as alternatives to synthetic polymers because they are better at being renewable and biodegradable. Reinforcement techniques like grafting and mixing are being used to further enhance their properties. One of the best things about PLA is that it is easy to get, biodegradable, flexible, and can be strengthened with different natural fibers and fillers. Bioplastics are being explored as viable alternatives to traditional synthetic plastics, in light of international agreements concerning plastics.Tétel Korlátozottan hozzáférhető A Quick Study on The Basics of Dynmaical Fields and Their PotentialsABDELRAZEQ, ALHASAN; Trócsányi , Zoltán; DE--Természettudományi és Technológiai Kar--Fizikai IntézetAmong the most compelling topics within this discipline are the dynamics of cosmological fields and the enigmatic forces driving the universe’s accelerated (or decelerated) expansion, commonly attributed to dark energy. This thesis embarks on a systematic study of dynamical fields, delving into their mathematical formulations, physical interpretations, and cosmological implications.Tétel Korlátozottan hozzáférhető Accumulation and translocation of metals in Sudan grass during a 3-month-long field experimentMunuhe, Esther; Tőzsér, Dávid; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetHeavy metal accumulation in plants is a critical aspect of phytoremediation strategies aimed at mitigating environmental pollution. A study was conducted in which we investigated the heavy metal accumulation in Sudan grass ((Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) cultivated in a contaminated area located in Lovász-zug. We monitored metal accumulation in the roots, stems and leaves to assess their remediation potential. Through analysis, we identified notable variations in the accumulation capacity of different metals within the plant organs with time. Based on the results obtained, our study concluded Sudan Grass as a tolerant plant species in soils with low to moderate levels of contamination. The main depository organ of Sudan grass is the root. It can be effectively utilized to phytoremediate heavy metal contaminated soils through extraction, stabilization and transfer processes in the plant organs. The findings prospects Sudan grass as a promising candidate for phytoremediation.Tétel Korlátozottan hozzáférhető Accumulation and translocation of metals in Sudan grass during a 3-month-long field experimentMunuhe, Esther; Tőzsér, Dávid; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetHeavy metal accumulation in plants is a critical aspect of phytoremediation strategies aimed at mitigating environmental pollution. A study was conducted in which we investigated the heavy metal accumulation in Sudan grass ((Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) cultivated in a contaminated area located in Lovász-zug. We monitored metal accumulation in the roots, stems and leaves to assess their remediation potential. Through analysis, we identified notable variations in the accumulation capacity of different metals within the plant organs with time. Based on the results obtained, our study concluded Sudan Grass as a tolerant plant species in soils with low to moderate levels of contamination. The main depository organ of Sudan grass is the root. It can be effectively utilized to phytoremediate heavy metal contaminated soils through extraction, stabilization and transfer processes in the plant organs. The findings prospects Sudan grass as a promising candidate for phytoremediation.Tétel Korlátozottan hozzáférhető Accumulation patterns of metals in selected plant species - meta-analysisYelamanova, Ayash; Edina Kundrát-Simon, Edina; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetThe study investigates the concentration and accumulation of heavy metals in amaranth plant tissues. The results indicate that the accumulation pattern of metals is different. The study also demonstrates that heavy metals were translocated from soil to plant organs. The Bioaccumulation Factor (BAF) was calculated for evaluation of the plants accumulation potential. Therefore, it can be dangerous to consume amaranth plants grown in polluted soil, because they greatly absorb much of these toxic metals.Tétel Korlátozottan hozzáférhető Accuracy Assessment of Airborne-Based Photogrammetry using UAVOyewole, Eriifeoluwa; Szabó, Gergely; DE--Természettudományi és Technológiai Kar--Földtudományi IntézetAccuracy assessment using unmanned aerial vehicles (UAVs) involves evaluating the accuracy and precision of the data collected through photogrammetric methods. This can be done by comparing the UAV data to a ground truth dataset, such as GPS or survey data. The accuracy assessment process involves establishing ground control points (GCPs) to ensure accurate positioning, and then comparing the UAV data to the ground truth data through statistical analysis. This statistical analysis includes calculating square values, absolute vertical difference, mean, standard deviation, and root mean square error (RMSE) values. The results of the accuracy assessment is used to draw conclusions about the validity of the photogrammetric method used in the study and to provide recommendations for future research or applications.Tétel Korlátozottan hozzáférhető Adsorption of bovine serum albumin on silica aerogel surface: Detailed kinetic model of the systemRanga, Madalina; Forgács, Attila; DE--Természettudományi és Technológiai Kar--Kémiai IntézetIn this thesis, I investigated the interaction of bovine serum albumin (BSA) and mesoporous silica aerogel, which can be used as a potential drug carrier and tissue scaffold in the biomedical field. Since bovine serum albumin is similar to human serum albumin (HSA), it is suitable for modeling the aerogel-protein system.During the experiments, BSA adsorption was observed on the mesoporous silica surface, which was confirmed by light microscopic examinations. The obtained UV-vis kinetic data were corrected using the Dual-Wavelength Method of background correction, to eliminate the background caused by the turbidity of the aerogel suspension. The results suggest that a complex process occurs after the injection of BSA solution into the aerogel suspension.Tétel Korlátozottan hozzáférhető Advanced glycation end productsDat, Pham Thai; Barna, Teréz; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetAdvanced glycation end products (AGEs) are a heterogeneous group of compounds formed by non-enzymatic interactions between the carbonyl groups of reducing sugars and free amino groups of proteins, lipids, or nucleic acids. Browning, fluorescence, and protein cross-linking may occur as a result of the Maillard process, which produces AGEs. AGEs can be produced in the body, but they can also come from outside the body, such as smoking and certain foods. The concept of AGEs receptor - RAGE is mentioned. In this thesis research, the theory on AGEs classifications, absorption, and toxic AGE will be reviewed. In addition, the contents of AGEs in food and beverages, the AGEs reduction in food processing will be discussed.Tétel Korlátozottan hozzáférhető Allogeneic reactions of pre-activated CAR T cells on target-negative cancer cellsLi, Artyom; Nagy, Lőrinc; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetT cells were isolated from 2 donor's PBMCs and transduced with HER2-CAR construct. The study evaluated the cytotoxic activity of HER2-CAR T cells against three cell lines: HER2-negative MDA cells and HER2-positive MDA-HER2 and MDA-HER2-231 cells. The results demonstrated significant cytotoxicity against MDA-HER2 cells, confirming the specificity of HER2-CAR T cells, while no cytotoxic effects were observed for HER2-negative MDA cells and MDA-HER2-231 cells, which had low expression of HER2 antigen. It implies that HER2-CAR T cells are unlikely to target healthy tissues with low expression of HER2. The same pattern was observed in the case of pre-activated T cells, and regardless of IL-2 and the donor of T cells.Tétel Korlátozottan hozzáférhető Alternative pathways of N-assimilation of Nicotinic acid in bacteria and fungi.Ben Lakhdhar, Aziz; Flipphi, Michel; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetThe thesis reviews different pathways by which certain species within the fungal and bacterial kingdoms degrade Nicotinic acid and its derivatives and use them as a Nitrogen source. Several pathways are observed in bacteria, while very little is known about fungi, with the pathway for Aspergillus nidulans being the only one studied in detail. The observed bacterial pathways include those of Arthrobacter nicotinovorans, several Bacillus species, Pseudomonas putida, Eubacterium barkeri, and some Ochtrobactrum species. The complete degradation leads to the production of Ammonium in each case. These pathways also highlight the involvement and importance of Nicotinic acid in energy production in the cell as it leads to nicotinamide adenine dinucleotide (NAD) which is involved in many energy-creating pathways.Tétel Korlátozottan hozzáférhető AN EXPERIMENTAL STUDY ON THE COMPETITION BETWEEN PISTIA STRATIOTES AND CERATOPHYLLUM DEMERSUM IN A FRESHWATER HABITATNjoroge, Beatrice; TÖRÖK, PÉTER; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetFreshwater ecosystem conservation is a desirable objective for the world especially with the current rise in human induced pressures like rapid globalization and climate change which have resulted in the rise of both invasive alien species numbers and their impacts as well on the ecosystem. The freshwater habitats as compared to marine and terrestrial areas have been recorded to be more susceptible to biological invasion due to factors like its landscape position, geographical isolation, interconnectivity and how its more prone to disturbances from human activities. Invasion from nonnative aquatic plants in such a valuable ecosystem is a significant threat as it could result in native plant species decline or even loss. This research seeks to understand the mechanisms, mainly focusing on shading and allelopathy, that facilitate the competitiveness of Pistia stratiotes, an invasive plant and how this affects Ceratophyllum demersum, a native plant in Europe. This was done by studying the results of a mesocosm experiment which was conducted placing both freshwater plants in four varying treatments. The Ceratophyllum demersum recorded a slight decline in its relative growth rate and total biomass due to shading from the Pistia stratiotes, on the other hand there was increase on the same parameters due to the allelopathic effects of Pistia stratiotes on the algae present in the water column. In studying this interaction, the research shows that floating macrophytes can affect submerged macrophytes both positively and negatively, also it underscores the importance of nutrient conditions in freshwater habitats, suggesting that controlling nutrient enrichment can mitigate Pistia stratiotes invasion in freshwater habitats.Tétel Korlátozottan hozzáférhető An overview on the current perspectives of Sickle cell in Nigeria.Chidi-Oparaojiaku, Adaukwu Joy Odichinma; Batta, Gyula; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetA literature review on the current state of sickle cell disease in Nigeria. I shed more light on the the burden created by sickle cell disease by delving into the various factors that contribute to the burden's growth. In order for this to be achieved, I read and wrote a detailed report on the status of sickle cell disease in Nigeria, to raise awareness about the disease and, hopefully, reduce the number of people affected in the future. I finally discussed some small measures that could be taken to reduce this burden by reducing the inefficiencies in the hospital care and management.Tétel Korlátozottan hozzáférhető Analysis Of Aromatic Compounds In Crude Oil Using Mass SpectrometryAdemola-Adesina, Mofiyinfoluwa; Nagy, Tibor; DE--Természettudományi és Technológiai Kar--Kémiai IntézetCrude oil is a naturally occurring, unrefined petroleum product composed of hydrocarbon deposits and other organic materials. I separated a crude oil sample into different fractions using the SARA fractionation method. I then used a ESI Q-TOF mass spectrometer to analyse the aromatic fractions gotten from the SARA fractionation. The raw data obtained from the mass spectrometer was exported into the excel program and sorted based on elemental composition and the m/z, intensities, carbon number,DBE etc. were determined. These parameters are then used to create diagrams, which provides more information on how to study the characteristics of the aromatic compound.Tétel Korlátozottan hozzáférhető Analysis of Cluster Shapes in the ATLAS Forward Proton DetectorIbrahim, Sara Ali Mahmoud; Zilizi, Gyula; Maciej, Trzebiński; DE--Természettudományi és Technológiai Kar--Fizikai IntézetATLAS is a general-purpose detector at the Large Hadron Collider (LHC), and it is equipped with two sets of special detectors, called Roman Pots, ALFA and AFP. The aim of this research work is to analyse the different classes of cluster hits and hence deepen the knowledge on how protons form the cluster hits in the AFP detector. In the years 2016-2018, ATLAS Collaboration took data of diffractive events with the newly installed Forward Proton detectors and since these devices are relatively new, there is a lot about their performance to be understood. The data used here is from 2017 low pile-up runs. To analyse these data, C++ and ROOT data analysis framework were the used tools. Methodology was as follows: first the basic properties of hits formed in the AFP detector were studied, then after making some event displays, I categorised various cluster shapes. Comparing some cluster shapes, it was observed that some shapes are more probable to occur than others. Moreover, it was concluded that cluster reconstruction in AFP should correctly recognise clusters in about 99% of the cases. This would help identify the origin of the cluster hits and lead to indications on how algorithms should form clusters.Tétel Korlátozottan hozzáférhető Analysis of coffee samples by GC-MS methodUdofia, Abimbola Kufre; Nagy, Tibor; DE--Természettudományi és Technológiai Kar--Kémiai IntézetCoffee is by far the most popularly consumed beverage worldwide and the most highly traded cash crop. It is enjoyed by many not only its caffeine but also because of its rich complex flavour. The aroma and rather strong taste of coffee is produced majorly by hundreds of volatile compounds that are generated during the roasting of harvested coffee beans. In this experiment we would be using a Gas chromatography with a mass spectrometer as the detector (GCMS) in order to elucidate the volatile components of 12 roasted coffee samples each from a different manufacturer. We would like to highlight the differences and similarities in coffee volatile compound content in relation to the differences in manufacturing processes, geographical origin of the coffee beans as well as cultivar of coffee.