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.
Böngészés
legfrissebb feltöltések
- TételKorlátozottan hozzáférhetőSynthesis and study of zwitterionic, Gd (III)-chelating macromolecules based on poly (glycidyl methacrylate)The purpose of this study is to complex Gd(III) ions using functionalized poly(glycidyl methacrylate), which was created. It was unsuccessful to functionalize the polymer after its initial synthesis using picolinic derivatives. We revised our approach and decided to functionalize the monomer (glycidyl methacrylate) first before polymerizing it. Amino acids were substituted for the original chelating agent. This turned out to be quite effective, and evidence from DOSY NMR, SEC chromatography, and proton affinity spectrums could support functionalization and polymerization. The relaxivitives were 4 times better when comparing complexation characterization to the Gd(III) aqua complex. This study adds to current research into better contrast agents with higher relaxivities that would allow for lower dosages of these agents without compromising the accuracy of the images produced by the diagnostic equipment.
- TételKorlátozottan hozzáférhetőAnisogamy is not related to life-history traits in AnuraAnisogamy is the ratio of the size of male and female gametes, that can explain the main aspects of sex differences. In our study, we investigated the relationship between anisogamy and various reproductive traits, such as SSD, mating systems, parental care, and clutch size and volume. The prediction was that anisogamy is associated with clutch size and clutch volume and not linked to SSD, mating systems, and parental care. The PGLS analysis did not reveal a significant correlation between any of these variables.
- TételKorlátozottan hozzáférhetőThe Effects of Heavy Metals on Human MetabolismThe impact of technological advancements is evident in the increasing levels of heavy metals in drinking water, which have surpassed the recommended limits imposed by regulatory bodies worldwide. Drinking water is a primary source of human exposure to heavy metals, such as arsenic, lead, nickel, cadmium, and mercury, and the consequences of consuming contaminated water have gradually gained attention from relevant personnel and departments. Occupational exposure to heavy metals occurs when these metals are used in industrial processes or materials, including color pigments and alloys. The detrimental effects of heavy metal contamination on human metabolism have been observed worldwide, including a series of adverse effects. The toxicity of heavy metals is attributed to the generation of reactive oxygen species, which cause oxidative damage and lead to health problems. Hence, water contaminated with heavy metals has high morbidity and mortality rates globally. This paper aims to raise awareness about the sources, distribution, and effects of various heavy metals on human metabolism.
- TételKorlátozottan hozzáférhetőThe effect of boron ion toxicity on Saccharomyces cerevisiae’s fermentation and alcohol yieldSaccharomyces cerevisiae has been used to produce various products from fermented beverages to bread, making it a relevant species to study due to its importance in food biotechnology. Due to its high importance across many industries for alcoholic beverage production thanks to its fermentation capacity, and high ethanol tolerance, this is an important species to study to continue improving production methods. The aim of this study was to analyze the growing of Saccharomyces cerevisiae in media with different concentrations of boron to determine the effect and toxicity of this metal ion. The alcohol concentration in the fermentation broths was measured by gas chromatography. Eight different concentrations of boric acid were used to test the growth and fermentation capacity of the strain. In all concentrations, boron showed no toxic or stimulating effect in either process, which proved that this metal ion has no effect on Saccharomyces cerevisiae’s metabolism.
- TételKorlátozottan hozzáférhetőToxicity of various metal ions on the enzymatic activity of Peroxidases in Zea mays germinating seedsThe aims of this experiment were to determine the effect of Potassium, Magnesium, Copper, Sodium, Lithium, Barium, and Calcium ions on the growth rate and enzymatic activity of Peroxidase in Zea mays roots and coleoptiles using pyrogallol and 24 well spectrophotometer. We deduced that overall excess metal ions used in this experiment did have a detrimental effect on the growth rate of Zea mays seedlings due to an increase in the production ROS (Reactive Oxygen Species) due to which the plant was increasing the activity of Peroxidase enzyme. We concluded that Zea mays that had lower growth rates, and subsequently higher enzyme activity were in fact because the majority of the damages to roots and shoots were done by the ROS for which the plants were increasing the Peroxidase enzyme activity. Moreover, we also concluded that as the growth rate decreased, the Peroxidase enzyme activity was increased in seedlings treated with excess metal ions, suggesting that ROS might be one of the significant factors in causing damage to the plant's roots and shoots and hindering their growth.