Lactic acid bacteria are natural habitants of human gastrointectinal tract. Among the most important are bacteria of genus Lactobacillus and genus Bifidobacterium that contain a lot of probiotic species. Probiotic species are used as food supplements. This work was focused on DNA separation from crude cell lysates of 4 food supplements using magnetic carrier P(HEMA-co-GMA) covered by carboxyl groups. DNA was reversible adsorbed to the carriers in the presence of PEG 6000 (16%) and NaCl (2 M) (final concentrations) and eluted into TE buffer. Lysis of cells from food supplements was performed by lysozyme, SDS and proteinase K. The amount of lysozyme was optimalized. Concentration of separated DNA was measured by spectrophotometric method. The amount of isolated DNA was suitable for PCR. Isolated DNA was used for PCR with universal primers, PCR specific for genus Lactobacillus and genus Bifidobacterium and for 9 different species-specific PCRs: Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus casei/paracasei, Streptococcus thermophilus, Bifidobacterium longum, Bifidobacterium bifidum and Bifidobacterium infantis. Amplicons were detected by agarose gel electrophoresis (1,8%). It was shown that DNA amplification methods are quick and precise for identification of studied species. The results of bacteria identification were compared with data provided by the manufacturer. In all food supplements, bacteria of genus Lactobacillus and Bifidobacterium were detected. However, only some species provided by manufacturer were identified by PCR in each tablet.

My master thesis is focused on design and realization fully automated system which will be used for the characterization of the organic FET structure, based on DPP derivatives with follow optimization of the characterization process. Program „MeasFET“ has been created at the LabVIEW surroundings that drives hardware gadgets was build-up during last year. Furthermore, initial tests were taken for optimalization process of charge carrier mobility measurements in derivatives DPP.

The content of this diploma thesis is a design of construction and selection of suitable material for upper-carrier part used for racing vehicle, produced by FDM 3D printing with the alternative option to replace an existing part, which was produced by conventional technique of CNC machining. Various versions of the experimental part are analyzed by FEM and compared in terms of safety coefficient with target to select the most appropriate construction design. The chosen version of the model is at the end compared with already existing part, which was also analyzed by FEM.

Converting solar energy to clean fuel has gained remarkable attention as an emerged renewable energy resource but optimum efficiency in photocatalytic applications has not yet been reached. One of the dominant factors is designing efficient photocatalytic semiconductors. The research reveals a theoretical investigation of optoelectronic properties of bismuth-based metal oxide and oxysulfide semiconductors using highly accurate first-principles quantum method based on density functional theory along with the range-separated hybrid HSE06 exchange-correlation functional. First, bismuth titanate compounds including Bi12TiO20, Bi4Ti3O12, and Bi2Ti2O7 were studied in a combined experimental and theoretical approach to prove its photocatalytic activity under UV light. They have unique bismuth layered structure, tunable electronic properties, high dielectric constant and low electron and effective masses in one crystallographic direction allowing for good charge separation and carrier diffusion properties. The accuracy of the investigation was determined by the good agreement between experimental and theoretical values. Next, BiVO4 with the highest efficiency for oxygen evolution was investigated. A discrepancy between the experimental and theoretical bandgap was reported and inspired a systematic study of all intrinsic defects of the material and the corresponding effect on the optical and transport properties. A candidate defective structure was proposed for an efficient photocatalytic performance. To overcome the carrier transport limitation, a mild hydrogen treatment was also introduced. Carrier lifetime was enhanced due to a significant reduction of trap-assisted recombination, either via passivation of deep trap states or reduction of trap state density. Finally, an accurate theoretical approach to design a new family of semiconductors with enhanced optoelectronic properties for water splitting was proposed. We simulated the solid solutions Bi1−xRExCuOS (RE = Y, La, Gd and Lu) from pure BiCuOS to pure RECuOS compositions. Starting from the thermodynamic stability of the solid solution, several properties were computed for each system including bandgaps, dielectric constants, effective masses and exciton binding energies. Several compositions with specific organization and density of Bi and RE atoms, were found to be appropriate for water splitting applications. In General, the presented results give further insights to the experimentalists and recommendations for appropriate future application and defect-design of each material.

Wireless communication systems utilize the wireless medium to perform over-the-air (OTA) data transfer. There are many factors that can impact the quality of wireless communications, such as medium imperfection, interfering environment, mismatch of transceivers, etc. To mitigate these problems and improve the quality of service (QoS), this research study is conducted on three important topics including synchronization techniques, impairment estimation theory and techniques, and interference alignment techniques. In this thesis, it firstly present a dual link algorithm to align and manage the interference of multiple-input and multiple-output (MIMO) networks. A field-programmable gate array (FPGA) prototype is designed for software defined radio (SDR) platforms. As one of the key components, a hardware efficient architecture is proposed for the implementation of singular value decomposition (SVD). Secondly, it proposes a maximum-likelihood (ML) based synchronization approach for carrier frequency synchronization for MIMO systems. The algorithm is also implemented on FPGA for real-time performance evaluation. Finally, as an exemplary study of machine learning techniques for wireless communications, a neural network (NN) based estimator is proposed to perform coarse frequency offset estimations for MIMO systems. The proposed NN based estimator can accommodate various channel models and the results show promising performance in terms of accuracy and estimation range. In summary, this thesis provides a comprehensive study on interference alignment, carrier synchronization, and impairment estimation using different approaches. Efficient hardware implementations for the key algorithms are also presented.

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Includes bibliographical references / Asymptomatic children can be a major reservoir of pharyngeal Group A Streptococcus (GAS) with reported figures ranging from <10% to >20% in developing countries. There is a need to document GAS carriage in school children, which, together with the molecular characterisation (M-typing) of strains harboured in the pharynx of carriers, will help to ascertain the extent to which disease strains are prevalent amongst carriers. This background information would serve to assist healthcare providers in diagnosing symptomatic GAS pharyngitis, as well as could potentially contribute to the development of a GAS vaccine. Currently, data on GAS carriage prevalence and M-type distribution in African countries are largely scant. We therefore undertook to perform a systematic review to determine the prevalence and type distribution of asymptomatic streptococcus carriage in children aged 5 -15years, residing in African countries. Methods: We conducted a comprehensive literature search among a number of databases, using an African search filter to identify GAS prevalence studies that report on children between the ages of 5 - 15 years who reside in African countries. Electronic searches were complemented by a hand search performed on reference lists of potentially included studies. The search was not limited by year of publication and language. Two evaluators independently reviewed, rated, and abstracted data from each article. Prevalence estimates were pooled in a meta-analysis and stratified according to region and study design using Stata®. Specifically, we applied the random effects metaprop routine to aggregate prevalence estimates and account for between study variability in calculating the overall pooled estimates and 95% CI for GAS carriage prevalence.

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Introduction: A Neisseria meningitidis carrier study has been conducted among students at Örebro university in Sweden in 2018 and 2019. Pharyngeal samples were collected from 3489 students. PCR for the genes ctrA and crgA was run on all samples. The positive samples were then cultured on agar plates to find the N. meningitidis. In 349 of the PCR positive samples, no N. meningitidis could be isolated, which raised the question if other bacteria could have these genes. The most likely bacteria to have these genes were assumed to be other species within the genus Neisseria. Aim: To identify whether other neisserial species have the ctrA and crgA genes. Methods: The 349 samples were cultured on agar plates for two days. The species were then identified by MALDI-TOF MS. The isolated Neisserial species and some other species as controls were saved. PCR for ctrA and crgA genes were then run on these bacteria to determine whether they possessed these genes. Results: Five N. meningitidis that had been missed by the first round of culture were identified. Seventy-five other colonies of neisserial species were isolated. N. subflava (n=40) were the most common. Nine (12 %) were crgA positive but none were ctrA positive. At least one crgA positive colony was found in four of the five different non-meningococcal neisserial species isolated in this study. Conclusion: The crgA gene seems quite common among non-meningococcal neisserial species while ctrA seems to be specific for N. meningitidis

Traditional chemical looping technologies utilize solid oxygen carriers and has some disadvantages, especially when solid fuels like coal are used. In this work, a novel chemical looping process using gaseous metal oxide as oxygen carrier was proposed. The reaction of activated charcoal with gas-phase MoO3 was studied for the first time. The experiments were conducted isothermally at different temperatures in a fixed-bed reactor. The apparent activation energy of the reaction was calculated and suitable kinetic models were determined. The results and analysis showed that the proposed concept has potential in both coal chemical looping combustion and gasification process. To further investigate the mechanism of carbon oxidation by gas-phase MoO3, the adsorption of a gaseous (MoO3)3 cluster on a graphene ribbon and subsequent generation of COx was studied by density functional theory (DFT) method and compared with experimental results. The (MoO3)n -graphene complexes show interesting magnetic properties and potentials for nanodevices. A comprehensive analysis of plausible reaction mechanisms of CO and CO2 generation was conducted. Multiple routes to CO and CO2 formation were identified. The (MoO3)3 cluster shows negative catalytic effect for CO formation but does not increase the energy barrier for CO2 formation, indicating CO2 is the primary product. Mechanism of the homogenous MoO3 - CO reaction was studied and showed relatively low energy barriers. The DFT result accounts for key experimental observations of activation energy and product selectivity. The combined theoretical and experimental approach contributes to the understanding of the mechanism of reactions between carbon and metal oxide clusters. To gain a better understanding of the MoO2 oxidation process, the adsorption and dissociation of O2 on MoO2 surface were studied by DFT method. The results show that O2 molecules prefer to be adsorbed on the five-coordinated Mo top sites. Density of states analysis shows strong hybridization of Mo 4d orbitals and O 2p orbitals in the Mo-O bond. Clean MoO2 slab and slabs with O2 adsorption are metallic conductors, while the surface with high O atom coverage is reconstructed and becomes a semiconductor. Surface Mo atoms without adsorbed O or O2 are spin-polarized. The oxygen adsorption shows ability to reduce the spin of surface Mo atoms. The adsorption energy of O2 and O atoms decreases as coverage increases. The transition states of O2 dissociation were located. The energy barriers for O2 dissociation on five-coordinated and four-coordinated Mo top sites are 0.227 eV and 0.281 eV, respectively.