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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Analysis of multi-generational father-son pairs using a YFiler Plus PCR amplification kit and a ForenSeq DNA signature prep kit

Folwick, Margo 11 November 2021 (has links)
Y-chromosome testing has become more prevalent in recent years as a means of identifying forensic samples using STRs or identifying biomarkers for disease or determining geographic origins of populations. Additionally, Y-chromosome analysis is especially useful in paternity testing as the Y chromosome is inherited paternally and the male-specific region of the Y chromosome does not undergo any recombination events, allowing the genotypic data of both the father and son to be identical. Though in most cases a father-son pair will have the same Y-allelic data, random mutations like allele insertions and deletions can occur, which can interfere and result in incorrect conclusions in regards to paternity testing, forensic analysis, or genealogy. Though the exact mechanism of Y loci mutability is unknown, postulations of factors that can cause mutations have been studied, as well as attempts to determine mutation rate specific to each locus. A multi-generational pedigree consisting of 9 males was analyzed using two different methodologies: capillary electrophoresis and next-generation sequencing. The samples were amplified using either a ForenSeq™ Signature DNA Prep Kit (Verogen, San Diego, CA) or a YFiler™ Plus PCR Amplification Kit (Thermo Fisher Scientific, Waltham, MA). Between the two methods, five Y-STR loci were identified as being discordant between a father-son pair. Next-generation sequencing identified an allele insertion at DYS385a/b, resulting in a potential tri-allelic locus, but was disproved after comparison with the capillary electrophoresis data of the sample. The capillary electrophoresis data identified four discordances between father-son pairs, one of which was an allele mutation with a gain of a repeat at DYS458. At DYS 389II, an allele insertion was identified, but was contradicted after comparison with the next-generation sequencing data. There was a potential null allele at DYS518 and either an OL variant allele or a 2 base pair deletion at DYS481. Following peak height ratio, stutter, and comparative analysis between the genotypic data of the two analysis methods, two of these discordances were proven to be errors, one was a definitive mutational event, and the other two could neither be confirmed nor denied due to differences in loci tested in each kit.
292

Využití kapilární elektroforézy pro stanovení tenzidů ve vodách / Application of capillary electrophoresis for determination of surfactants

Langová, Lenka January 2009 (has links)
Tensides rank among the surfactants with ability to reduce surface tension. This ability is used to remove impurities. Surfactants can be divided into four basic groups: anionic, cationic, nonionic and zwitterionic. Anionic surfactants belong to the most widespread surfactants in the Czech Republic today. They get into sewage waters from various cleansing and washing agents which are used both in households and industry. So this diploma thesis deals with their assessment by application of capillary electrophoresis.
293

Analytické metody na mikrofluidním čipu / Analytical methods on a chip

Slavík, Jan January 2013 (has links)
This work deals with fabrication and test of microfluidic chip for separating substances. For separation of substances is used electrophoresis and detection is by integrated electrodes.
294

Établissement des diagrammes de spéciation à plusieurs températures du plutonium (V) pour prédire son comportement dans les eaux de surface / Establishment of speciation diagrams of plutonium (V) at several temperatures in order to predict its behavior in surface waters.

Alexandre, Jean-Charles 21 November 2018 (has links)
Dans le cadre de la surveillance environnementale, le devenir du plutonium au sein des différents milieux et en particulier au sein des eaux de surface est important notamment en raison de sa radiotoxicité. Dans ces milieux, la forme pentavalente du plutonium est prédominante et est fortement complexée par les carbonates. Le couplage EC-ICP-MS, technique ayant déjà été éprouvée pour la spéciation des actinides, a été retenu pour déterminer les constantes thermodynamiques associées à la formation de ces complexes.L’étude menée sur le plutonium (VI) a permis d’obtenir des constantes de stabilité à 25°C. A partir de ces valeurs, les coefficients d’interaction spécifique ont été ré-évalués par rapport à celles reportées par l’AEN. Le diagramme de spéciation en solution du Pu(VI) en présence d’ions carbonate a été établi. Il suggère la complexation de la forme plutonyle par les ions carbonate dès pH=3.Les travaux réalisés sur les actinides (V) (Np et Pu) ont permis de déterminer à la fois les constantes de stabilité des complexes carbonates puis les enthalpies et entropies molaires de réaction à partir de l’étude menée en température. Expérimentalement, l’analogie entre le neptunium et le plutonium a été confirmée. Afin de mieux comprendre le comportement du plutonium au sein d’eaux de surface, la détermination des enthalpies et entropies a été nécessaire. Les diagrammes de spéciation établis à partir de ces données montrent une quasi similarité dans la répartition chimique des espèces du plutonium pentavalent sans considération de la localisation de l’eau de surface analysée. / In the field of environmental control, the behavior of plutonium in various media and particularly in surface waters is relevant taking into account its radiotoxicity. Carbonate ions widely present in these media mainly complex pentavalent plutonium. In this field, CE-ICP-MS coupling, which was already used for actinides speciation, has been considered for the determination of thermodynamic constants associated to plutonium carbonate complexes.The study developed on plutonium (VI) allowed determining the stability constants at 25°C. From these values, the specific interaction coefficients based on the values recommended by the NEA have been reevaluated. The speciation diagram of Pu(VI) in aqueous carbonate solution has been established and shows the complexation of the plutonyl form by carbonates complex beyond pH=3.The works realized on the complexation of actinides (V) (Np and Pu) by carbonate ions at different temperatures allowed determining both the stability constants and the molar enthalpies and entropies of reaction. Experimentally, the analogy between neptunium and plutonium has been observed and allowed the determination of values which are more precise and consistent with those of the literature. For a better understanding of the plutonium behavior in surface waters, the determination of enthalpies and entropies has been necessary. The speciation diagrams established from these values show a near similarity in the chemical distribution of plutonium species without any further consideration of the analyzed surface water location.
295

Determination of organic phosphorus in soil samples by capillary zone electrophoresis coupled to electrospray ionization mass spectrometry

Giannakoudi, Theodora January 2020 (has links)
Chemical substances that are either produced by nature or by humankind have a consequence on the environment when they are accumulated to a great extent. One of nature’s major problem is that of the eutrophication of surface waters, which is caused by inorganic and organic phosphorus compounds and, in particular, from a group known as Inositol Phosphates. There are six different forms of these inositols and are commonly found in soil and sediment samples. The conducted project was aimed to develop an analytical method that could efficiently analyze and separate all six with repeatable results. As such, soil samples were collected two times from two forest locations and two crop field locations. The first time the soil samples were left overnight to dry in a drying oven while on the second time, the samples left to dry at room temperature. When the samples were considered dry enough, they processed to reach grain size and extracted with a mixture of NaOH and Titriplex® III. The extracted soil samples, the standard solutions containing inositols, and the spiked extracted soil samples with inositol solution were all analyzed with an instrumental combination of a Capillary Electrophoresis instrument coupled manually to an Electrospray mass spectrometer, where the first was operated at reversed mode and the second at negative mode. To achieve the best feasible separation, several background electrolyte solutions were created along with a large number of sheath liquids regulated by an LC pump, two Capillary Electrophoresis methods, and twenty-five distinct MS methods, all tested through extensive screening to obtain the best possible combination of parameters. Out of the obtained results from the runs, four background electrolyte solutions, two MS methods, one sheath liquid controlled by one specific flow rate, and one Capillary Electrophoresis method exhibited promising potentials with a satisfying outcome. However, the intense pulsation of the spray cone observed for many of the runs, the manual protrusion of the Capillary Electrophoresis fused silica capillary, and some random errors, the repeatability of the method is called into question.
296

A comparison of the Illumina MiSeq FGX™ System against capillary electrophoresis in the analysis of two-person mixtures

McEvoy, David Patrick 15 July 2020 (has links)
The following is a comparison study of the Globalfiler™ PCR Amplification Kit analyzed on an ABI 3130 Genetic Analyzer Capillary Electrophoresis (CE) versus the ForenSeq™ DNA Signature Prep Kit analyzed on the MiSeq FGx™ System. The MiSeq FGx™ System measures results by Allele Read Count (ARC), while the CE measures results as Relative Fluorescent Units (RFU). Mixture samples were prepared in ratios of 1:1, 1:4, and 1:10 in replicates of four using a female major contributor and a male minor contributor, intended to represent some commonly seen mixture samples ratios in forensic cases [48]. Both systems performed equally well for the 1:1 mixture while the MiSeq FGx™ System had improved accuracy and precision for the 1:4 mixture compared to CE (4.033 + 1.506 ARC and 4.678 + 2.093 RFU, respectively). The MiSeq FGx™ System showed increased variation in the 1:10 mixture compared to CE (10.347 + 5.184 ARC and 9.311 + 3.363 RFU, respectively). Over the four replicates, the MiSeq FGx™ System had a total of 15 out of 528 possible alleles (2.84%) dropout compared to a total of 13 out of 384 possible alleles (3.39%) dropout on CE. The additional loci analyzed by the MiSeq FGx™ System results in a lower percentage of alleles lost due to dropout compared to CE. Isoalleles in sequence data may reveal the presence of minor contributor alleles that would otherwise be masked by the major contributor in length-based STR analysis. The presence of isoalleles are most helpful in mixture ratios greater than 1:1, where it is easier to assign alleles to a specific contributor. In certain cases, deconvolution of loci with shared alleles may not be improved by sequencing if intra-contributor isoalleles are present. Unless using known reference profiles, it is difficult to accurately assign alleles to contributors when intra-contributor isoalleles are present. Additionally, the sequencing data from the MiSeq FGx™ System provided information to aid the separation of stutter from true alleles. Previous studies report a significant increase in the amount of alleles present at some loci due to differences by nucleotide sequence, which may improve the discriminating power of those loci [31,52,53,54]. With all its potential, there is still much room for sequencing technology to improve before it becomes a standard analysis method in forensic laboratories.
297

Analysis of reproduction proteins from butterflies / Analys av reproduktionsproteiner från fjärilar

Xu, Jiawei January 2011 (has links)
Male butterflies have some certain pathways to prevent the female butterfly which has mated with them from mating with other butterflies. Research shows that some proteins from the male butterflies may play an important role in this mechanism. To investigate how the pathway works, the proteins contained in the spermatophore which is injected into the female butterfly by the male one during mating are very important. In this study, the butterfly spermatophore proteins were mainly studied. The proper procedures to obtain the spermatophore from the female body were developed. Since capillary electrophoresis (CE) has many advantages for separation and detection of low amounts of sample, it was used in this study in order to separate the proteins obtained from spermatophores. Finally, Mass Spectrometry (MS) was performed to analyze the proteins after separation in order to identify the proteins. This thesis mainly introduced the following points: 1. The method for obtaining spermatophores from butterfly bodies and the procedures for extracting proteins from spermatophores. 2. Optimized methods and conditions of Capillary Zone Electrophoresis (CZE) for butterfly spermatophore proteins. Several CZE methods and sets of conditions were compared in order to find the optimized ones. 3. Protein samples were applied to Mass Spectrometry (MS) to try to analyze and identify them. Moreover, the effect of using ZiptipsTM for sample pretreatment was discussed.
298

Elektroforetické stanovení tantalu v recyklátech chladicích kapalin / Electrophoretic Determination of Tantalum in Recycled Coolants

Gogulin, Semen January 2021 (has links)
This master thesis deals with the development of electrophoretic methods for determination of tantalum in recycled coolants used in the production of tantalum capacitors, as well as the separation of tantalum from chemically similar niobium. Developed methods are based on the formation of negatively charged complexes of tantalum and niobium with a number of ligands added to the separation electrolyte, especially tartaric and citric acid and 4-(2-pyridylazo)resorcinol. The separations were performed in a fused silica capillary of the inner diameter of 50 µm and the effective length of 36.5 cm, a negative voltage of -25 kV was applied to the capillary. Using a separation electrolyte containing 0.1 mol·l-1 of tartaric and citric acid at pH = 2, separation of niobium and tantalum was achieved in less than 3 minutes; the absorption spectrometric detection was carried out in the ultraviolet region at a wavelength of 200 nm, the detection limit was 2.8 ppm of tantalum, and the quantification limit was 9.2 ppm of tantalum. Addition of 4-(2-pyridylazo)resorcinol reduced the detection limit to 0.8 ppm of tantalum and the quantification limit to 2.6 ppm of tantalum; the electrolyte contained 0.1 mmol·l-1 of 4-(2-pyridylazo)resorcinol, 10 mmol·l-1 of tartaric acid, 10 mmol·l-1 of citric acid, and 25 mmol·l-1...
299

Dose-Response Effects of Chronic Lithium Regimens on Spatial Memory in the Black Molly Fish

Creson, Thomas K., Woodruff, Michael L., Ferslew, Kenneth E., Rasch, Ellen M., Monaco, Paul J. 01 January 2003 (has links)
Lithium is widely used in the management of bipolar disorder, yet memory impairment is a serious side effect. To assess the effects of lithium on spatial working and reference memories, we have employed a plus maze utilizing spontaneous alternation (SA) and place-learning paradigms in two experiments with the black molly fish. Four treatment groups were gavaged with 20 μl of a 10, 100, or 1000 mM lithium chloride (LiCl) solution or ddH2O vehicle every 12 h for 22 to 24 days. On Day 15, subjects began an 8-day SA task or a 10-day place-learning task. Results indicate that there is a significant difference in SA performance among the treatment groups for Days 1, 2, and 3. Results of the place-learning task indicate that the 1 M dose group needed significantly more trials to reach criterion and made significantly fewer correct first choices than the other dose groups. Capillary ion analysis determinations of plasma and brain lithium levels illustrate linear dose-response relationships to doses administered. Regression analyses indicate that there is a relationship between SA performance and plasma/brain lithium levels during the initial part of testing. Collectively, the results indicate that chronic lithium administration impairs spatial working and reference memories.
300

Modifikace kapilární stěny grafenem pro separační aplikace / Modification of capillary wall by graphene for separation applications

Ptáčková, Aneta January 2021 (has links)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Aneta Ptáčková Supervisor: PharmDr. Lukáš Lochman, Ph.D. Title of thesis: Modification of capillary wall by graphene for separation applications Capillary electrophoresis (CE) is a highly efficient separation method. Substances are separated due to their different mobility in an electric field. The CE modes of operation can be modified in different ways, e.g. capillary electrochromatography or micellar electrokinetic capillary chromatography. Modification of the inner wall of the capillary is believed to help improve separation efficiency and selectivity. Graphene is carbon with a hexagonal structure in form of two-dimensional sp2 single-atom-thick sheets. Graphene seems to be a suitable material for separation application due to its excellent properties such as large surface area and affinity to aromatic ring through π-π interactions. Our work is focused on the modification of the capillary wall by graphene. One of the methods of capillary wall modification is the Layer-by-Layer method via layering of differently charged substances bounded by electrostatic forces. Another method is chemical coating employing covalent interactions. Different combinations of polymers...

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