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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.
121

Method development and applications of Pyrosequencing technology

Gharizadeh, Baback January 2003 (has links)
<p>The ability to determine nucleic acid sequences is one ofthe most important platforms for the detailed study ofbiological systems. Pyrosequencing technology is a relativelynovel DNA sequencing technique with multifaceted uniquecharacteristics, adjustable to different strategies, formatsand instrumentations. The aims of this thesis were to improvethe chemistry of the Pyrosequencing technique for increasedread-length, enhance the general sequence quality and improvethe sequencing performance for challenging templates. Improvedchemistry would enable Pyrosequencing technique to be used fornumerous applications with inherent advantages in accuracy,flexibility and parallel processing.</p><p>Pyrosequencing technology, at its advent, was restricted tosequencing short stretches of DNA. The major limiting factorwas presence of an isomer of dATPaS, a substitute for thenatural dATP, which inhibited enzyme activity in thePyrosequencing chemistry. By removing this non-functionalnucleotide, we were able to achieve DNA read-lengths of up toone hundred bases, which has been a substantial accomplishmentfor performance of different applications. Furthermore, the useof a new polymerase, called Sequenase, has enabled sequencingof homopolymeric T-regions, which are challenging for thetraditional Klenow polymerase. Sequenase has markedly madepossible sequencing of such templates with synchronizedextension.</p><p>The improved read-length and chemistry has enabledadditional applications, which were not possible previously.DNA sequencing is the gold standard method for microbial andvial typing. We have utilized Pyrosequencing technology foraccurate typing ofhuman papillomaviruses, and bacterial andfungal identification with promising results.</p><p>Furthermore, DNA sequencing technologies are not capable oftyping of a sample harboring a multitude of species/types orunspecific amplification products. We have addressed theproblem of multiple infections/variants present in a clinicalsample by a new versatile method. The multiple sequencingprimer method is suited for detection and typing of samplesharboring different clinically important types/species(multiple infections) and unspecific amplifications, whicheliminates the need for nested PCR, stringent PCR conditionsand cloning. Furthermore, the method has proved to be usefulfor samples containing subdominant types/species, and sampleswith low PCR yield, which avoids reperforming unsuccessfulPCRs. We also introduce the sequence pattern recognition whenthere is a plurality of genotypes in the sample, whichfacilitates typing of more than one target DNA in the sample.Moreover, target specific sequencing primers could be easilytailored and adapted according to the desired applications orclinical settings based on regional prevalence ofmicroorganisms and viruses.</p><p>Pyrosequencing technology has also been used forclone-checking by using preprogrammed nucleotide additionorder, EST sequencing and SNP analysis, yielding accurate andreliable results.</p><p><b>Keywords:</b>apyrase, bacterial identification, dATPaS, ESTsequencing, fungal identification, human papillomavirus (HPV),microbial and viral typing, multiple sequencing primer method,Pyrosequencing technology, Sequenase, single-strandedDNA-binding protein (SSB), SNP analysis</p>
122

Burnout and engagement in a South African university student sample : a psychometric analysis / Carina Gauché

Gauche, Carina January 2006 (has links)
In recent years, the concept of burnout has been expanded and is currently a concern in all professions and occupational groups. Nowadays it is widely acknowledged that people in almost any occupation could develop burnout. To-date, only two studies have examined students' experiences of burnout. Therefore, research regarding this phenomenon in students seems warranted. The objective of this study was to firstly investigate the psychometric properties of adapted versions of the Maslach Burnout Inventory and Utrecht Work Engagement Scale in a sample of students from a tertiary institution, and secondly to consider the role of biographical variables in relation to burnout and engagement levels. A cross-sectional survey design was used to attain the research objectives. For the purposes of this study, an availability sample of students (N=353) majoring in Organisational Behaviour was drawn at one point in time. The adapted Maslach Burnout Inventory - Student Survey (MBI-SS) and the Utrecht Work Engagement Scale - Student Survey (UWES-S) as well as a biographical questionnaire were administered. Structural equation modelling confirmed two-factor models of Burnout (consisting of Exhaustion and Cynicism) and Engagement (consisting of Vigour and Dedication). Biographical variables which appear to be predictive of differences in levels of student burnout are home language, overall health status and consideration given to quitting their studies, while engagement is related to home language, academic year of study and consideration given to quitting studies. Recommendations for future research were also made / Thesis (M.A. (Industrial Psychology))--North-West University, Potchefstroom Campus, 2006.
123

Sacred image, urban space image, installations, and ritual in the early medieval Roman forum /

Kalas, Gregor A. January 1999 (has links)
Thesis (Ph. D.)--Bryn Mawr College, 1999. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 353-379).
124

Grawitz, Genzken, Gebhardt drei Karrieren im Sanitätsdienst der SS

Hahn, Judith January 2007 (has links)
Zugl.: Berlin, Freie Univ., Diss., 2007
125

Estudo de transições durante o processo de desenovelamento térmico da RNase A por meio da calorimetria (DSC) e espectroscopia de correlação bidimensional no infravermelho médio (2D-IR) /

Martins, Danúbia Batista. January 2011 (has links)
Orientador: Marinônio Lopes Cornélio / Banca: Antônio José da Costa Filho / Banca: André Luiz Galo / Resumo: Esse trabalho tem por objetivo estudar as transições conformacionais, induzidas termicamente, na Ribonuclease A. Esta abordagem foi realizada aplicando!se a técnica de calorimetria diferencial de varredura (DSC) e infravermelho médio com transformada de Fourier (FTIR), associando a técnica de análise de correlação bidimensional (2D! COS), variável!variável (VV) e sample sample (SS). A partir dos dados de DSC determinamos a variação de entalpia do sistema (∆Hcal) que foi de 587 kJ/mol. Também identificamos as temperaturas de pré (36, 39, 43, 49 e 59°C), pós transição (71°C) e temperatura de melting (65°C), além da determinação do ∆Hcal para cada uma das transições. A análise de correlação bidimensional sample!sample (SS) também foi capaz de identificar as mesmas temperaturas encontradas por DSC. Por sua vez, a análise de correlação bidimensional variável!variável (VV) descreveu a evolução conformacional das estruturas secundárias da proteína durante o desenovelamento térmico / Abstract: This work aims to study the thermally!induced conformational transitions in Ribonuclease A. This approach was performed by applying the technique of differential scanning calorimetry (DSC) and medium infrared Fourier transform spectroscopy (FTIR), linking the technique of correlation analysis (2D!COS), variable!variable (VV) and sample !sample (SS). From DSC data determine the enthalpy change of the system (SHcal) which was 587 kJ / mol. We identified the pre temperatures (36, 39, 43, 49 and 59 ° C), post transition (71 ° C) and melting temperature (65 ° C), besides determination of SHcal for each transition. The two!dimensional correlation analysis sample! sample (SS) was also able to identify the same temperatures found by DSC. In turn, the two!dimensional correlation analysis of variable!variable (VV) described the conformation evolution of the protein secondary structures during thermal unfolding / Mestre
126

Otimização de métodos analíticos e caracterização da farinha de trigo refinada: uma contribuição à Tabela Brasileira de Composição de Alimentos

Araujo, Rennan Geovanny Oliveira 17 May 2007 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-04-07T17:53:48Z No. of bitstreams: 1 Tese_de_Doutorado_Rennan_G_O_Araujo.pdf: 2718676 bytes, checksum: 59eab9c3f63867e32dff273384239532 (MD5) / Approved for entry into archive by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-05-10T17:42:10Z (GMT) No. of bitstreams: 1 Tese_de_Doutorado_Rennan_G_O_Araujo.pdf: 2718676 bytes, checksum: 59eab9c3f63867e32dff273384239532 (MD5) / Made available in DSpace on 2016-05-10T17:42:10Z (GMT). No. of bitstreams: 1 Tese_de_Doutorado_Rennan_G_O_Araujo.pdf: 2718676 bytes, checksum: 59eab9c3f63867e32dff273384239532 (MD5) / CNPq e FAPESB / A farinha de trigo é um produto muito importante consumida em muitas partes do mundo. A determinação de seus constituintes é de interesse tanto nutricional como toxicológico. No intuito de rastrear nutrientes e contaminantes presentes na composição mineral da farinha de trigo consumida em cidades brasileiras foi desenvolvido um estudo de investigação de forma a ampliar dados sobre tal gênero alimentício. Foram desenvolvidos quatro trabalhos para determinação de metais em farinha de trigo usando técnicas espectrométricas atômicas. O primeiro trabalho consistiu na determinação de manganês em amostras coletadas na cidade de Salvador, Bahia, Brasil - utilizando amostragem suspensão e detecção por espectrometria de absorção atômica com chama (FAAS). A concentração de manganês nas amostras variou entre 5,2 ± 0,7 a 7,6 ± 0,5 μg g-1. Os limites de detecção e de quantificação foram 0,13 e 0,44 μg g-1, respectivamente. A precisão foi expressa através do desvio padrão relativo (%RSD) foi de 3,5 % (n=10). A exatidão foi confirmada através de análise de três materiais de referência certificados de farinha de arroz. O uso da calibração com padrões aquosos facilitou um procedimento simples e rápido para determinação de manganês em farinha de trigo. No segundo trabalho, foram comparados dois métodos analíticos para determinação de cádmio empregando a espectrometria de absorção atômica com atomização eletrotérmica em forno de grafite (GF AAS) sem a digestão da amostra de farinha de trigo através da amostragem direta de sólidos (SS) e a amostragem em suspensão com múltiplas injeções (SlS) como introdução. Após a otimização das condições usando a mistura paládio e magnésio como modificador químico, a temperatura de pirólise usada foi de 800 ºC, e 1600 ºC como temperatura de atomização, sem observação de sinal fundo de absorção. A calibração versus padrões aquosos foi utilizado para ambos os métodos otimizados. Foram estabelecidas as figuras de mérito: massa característica 0,6 e 1,0 pg, limite de detecção (3σ, n = 10) 0,2 e 0,7 ng g-1, limite de quantificação (10σ, n = 10) 0,7 e 2,3 ng g-1 e precisão expressa como desvio padrão relativo (n=5) de 6 – 16% e 9 – 23% para SS e SlS, respectivamente. As análises de materiais de referência certificados de farinha de trigo, folhas de maças, farelho de milho e pão confirmaram a exatidão dos métodos. Seis amostras de farinha de trigo foram analisadas para determinação de cádmio coletadas em cidades brasileiras, sendo encontrado a concentração desse elemento variando entre 8,9 ± 0,5 e 13 ± 2 μg kg-1 nas amostras. Aplicou-se teste t-Student aos resultados obtidos pelo os dois métodos propostos, estando os dados concordantes para nível de 95% de confiança. O método SS foi escolhido como método de rotina, devido à sua simplicidade, a velocidade de análise e os melhores valores de figura de mérito. O terceiro trabalho, a composição mineral da farinha de trigo consumida no Brasil foi avaliada. Na etapa de amostragem foram coletadas 54 amostras em 15 cidades, incluindo as principais cidades brasileiras como: São Paulo, Rio de Janeiro, Salvador, Porto Alegre, Recife e outras. Os elementos determinados foram: cálcio, cobre, magnésio, manganês, ferro, fósforo, potássio e zinco. A técnica analítica empregada foi a espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). A validação do método (incluindo digestão e determinação) foi confirmada usando um material de referência certificado de farinha de trigo fornecido pelo NIST. Considerando as 54 amostras analisadas, os resultados demonstraram que os macronutrientes: cálcio, magnésio, potássio e fósforo encontram-se em média de 0,27; 0,35; 1,71 e 1,92 mg g-1, com variação da concentração de 0,11 – 1,96; 0,19 – 0,51; 0,76 – 3,16 e 0,81 – 7,15 mg g-1, respectivamente. Os micronutrientes: cobre, ferro, manganês e zinco encontram-se em média de 1,84; 37,82; 8,25 e 9,41 g g-1, com a variação de concentração de 1,00 – 2,80; 10,46 – 146,58; 3,89 – 14,74 e 5,07 – 13,93 g g-1, respectivamente. Os resultados foram avaliados também usando as técnicas de análise multivariadas: análise de componente principal (PCA) e análise de agrupamento hierárquico (HCA). Por fim, o quarto trabalho foi desenvolvido para determinação de Ba, Cr, Rb, Sr, V, Se e Mo empregando a espectrometria de massa com plasma indutivamente acoplado (ICP-MS) em 25 amostras de farinha de trigo coletadas em cidades brasileiras. Foi utilizado o procedimento de digestão assistida por microondas em sistema fechado. A validação do método foi confirmada através da adição e recuperação para todos analitos e análise de material de referência certificado de farinha de trigo NIST 1567a para Se, Mo e Rb. Os valores foram satisfatórios com uso de germano como padrão interno. Apreciando as 25 amostras analisadas, os resultados demonstraram que concentração variou entre 1,71 – 10,83 µg g-1 para Ba; 0,060 – 0,307 µg g-1 para Cr; 0,77 – 4,23 µg g-1 para Rb; 0,61 – 5,72 µg g-1 para Sr; 0,023 – 0,108 µg g-1 para V; 0,058 – 0,952 µg g-1 para Se e 0,115 – 0,684 µg g-1 para Mo. Os resultados foram avaliados também usando as técnicas de análise multivariadas: PCA e HCA. / The wheat flour is a very important product consumed in many parts of the world. The determination of its constituents is of interest both nutritional and toxicological. In order to trace nutrients and contaminants present in the mineral composition of wheat flour consumed in Brazilian cities was conducted a research study in order to expand data on such foodstuff. There have been four works for determination of metals in wheat flour using atomic spectrometric techniques. The first work was the determination of manganese in samples collected in the city of Salvador, Bahia, Brazil - using slurry and detection by flame atomic absorption spectrometry (FAAS). The concentration of manganese in the samples ranged between 5.2 ± 0.7 a 7.6 ± 0.5 μg g-1. The limits of detection and quantification were 0.13 and 0.44 μg g-1, respectively. The precision was expressed by the relative standard deviation (RSD%) was 3.5% (n=10). The accuracy was confirmed through analysis of three rice flour certified reference materials. The use of calibration standards agaisnt aqueous facilitated a simple and rapid procedure for determination manganese in wheat flour samples. In the second work, were compared two methods to cadmium determination employing graphite furnance atomic absorption spectrometry (GF AAS) without the digestion of the wheat flour sample, through direct solid sampling (SS) and slurry with multiple injections(SlS) as form of introduction. After the optimization of conditions using a mixture of palladium and magnesium as chemical modifier, the temperature pyrolysis used was 800 º C and 1600 º C as temperature, atomization, without remark the of background. The calibration against aqueous standards was used for both methods optimized. The parameter of merit were established: characteristic mass of 0.6 and 1.0 pg Cd, detection limit (3σ, n = 10) of 0.2 and 0.7 ng g-1, limit of quantification (3σ, n = 10) of 0.7 and 2.3 ng g-1 and precision expressed as standard deviation relative (n = 5) between 6-16% and 9-23% for SS and SlS, respectively. The analysis of certified reference materials of wheat flour, apples leaves, corn brad and brown bread confirmed the accuracy of the methods. Six samples of wheat flour were collected in Brazilian cities and analyzed for determination of cadmium. The cadmium concentration found range between 8.9 ± 0.5 and 13 ± 2 μg kg-1 in the samples. It was applied the Student's t-test results obtained for two methods proposed, and the data agreement on a 95% confidence level. The SS method was chosen as routine method, because of its simplicity, speed of analysis and the best values of parameter of merit. The third work, the mineral composition of wheat flour consumed in Brazil was evaluated. In the sampling step 54 samples were collected in 15 cities, including principal Brazilian cities such as: São Paulo, Rio de Janeiro, Salvador, Porto Alegre, Recife and others. The elements determinate were: calcium, copper, magnesium, manganese, iron, phosphorus, potassium and zinc. The samples were digested using nitric acid and hydrogen peroxide in open system. The analytical technique employed was Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES). The method validation (including digestion and determination) was performed using a certified reference material of wheat flour furnished by National Institute of Standards & Technology (NIST). Considering the 54 samples analyzed, the results demonstrated that the macronutrients: calcium, magnesium, potassium and phosphor have average content of 0.27, 0.35, 1.71 and 1.92 mg g-1, for concentration ranges of 0.11-1,96, 0.19-0.51, 0.76-3.16 and 0.81-7.15 mg g-1, respectively. The micronutrients: copper, iron, manganese and zinc have average content of 1.84, 37.8, 8.2 and 9.4 μg g-1, for concentration ranges of 1.00-2.80, 10.5-146.6, 3.9-14.7 and 5.1-13.9 μg g-1, respectively. The results were also evaluated using the multivariate analysis techniques: principal component analysis (PCA) and hierarchical cluster analysis (HCA). Finally, the fourth work was conducted to determination of Ba, Cr, Rb, Sr, V, Mo and employing inductively coupled plasma mass spectrometry (ICP-MS) in 25 samples of wheat flour collected in Brazilian cities. The procedure assisted by microwave digestion in closed system was used. The accuracy of the method was confirmed by the addition and recovery for all analytes and analysis of certified reference material of wheat flour NIST 1567 for Se, Mo and Rb. The parameter of merit were satisfactory with used isotope of german (74Ge) as internal standard. The 25 wheat flour samples were analyzed, the results showed concentration ranged between 1.71 - 10.83 μg g-1 for Ba, 0060 - 0307 μg g-1 for Cr, 0.77 - 4.23 μg g-1 to Rb; 0.61 - 5.72 μg g-1 for Sr; 0.023 – 0.108 μg g-1 to V; 0.058 – 0.952 μg g-1 for Se and 0.115 – 0.684 μg g-1 for Mo. The results were also evaluated using the techniques of multivariate analysis: PCA and HCA
127

Estudo de transições durante o processo de desenovelamento térmico da RNase A por meio da calorimetria (DSC) e espectroscopia de correlação bidimensional no infravermelho médio (2D-IR)

Martins, Danúbia Batista [UNESP] 27 May 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-27Bitstream added on 2014-06-13T20:29:19Z : No. of bitstreams: 1 martins_db_me_sjrp.pdf: 1774906 bytes, checksum: cae913e873e102a5cfd5c4dddccc9e4d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esse trabalho tem por objetivo estudar as transições conformacionais, induzidas termicamente, na Ribonuclease A. Esta abordagem foi realizada aplicando!se a técnica de calorimetria diferencial de varredura (DSC) e infravermelho médio com transformada de Fourier (FTIR), associando a técnica de análise de correlação bidimensional (2D! COS), variável!variável (VV) e sample sample (SS). A partir dos dados de DSC determinamos a variação de entalpia do sistema (∆Hcal) que foi de 587 kJ/mol. Também identificamos as temperaturas de pré (36, 39, 43, 49 e 59°C), pós transição (71°C) e temperatura de melting (65°C), além da determinação do ∆Hcal para cada uma das transições. A análise de correlação bidimensional sample!sample (SS) também foi capaz de identificar as mesmas temperaturas encontradas por DSC. Por sua vez, a análise de correlação bidimensional variável!variável (VV) descreveu a evolução conformacional das estruturas secundárias da proteína durante o desenovelamento térmico / This work aims to study the thermally!induced conformational transitions in Ribonuclease A. This approach was performed by applying the technique of differential scanning calorimetry (DSC) and medium infrared Fourier transform spectroscopy (FTIR), linking the technique of correlation analysis (2D!COS), variable!variable (VV) and sample !sample (SS). From DSC data determine the enthalpy change of the system (SHcal) which was 587 kJ / mol. We identified the pre temperatures (36, 39, 43, 49 and 59 ° C), post transition (71 ° C) and melting temperature (65 ° C), besides determination of SHcal for each transition. The two!dimensional correlation analysis sample! sample (SS) was also able to identify the same temperatures found by DSC. In turn, the two!dimensional correlation analysis of variable!variable (VV) described the conformation evolution of the protein secondary structures during thermal unfolding
128

Rechtsextremismus: Augen auf! Sehen - Erkennen - Handeln: Rechtsextremistische Symbole, Kennzeichen und Organisationen

Landeskriminalamt Sachsen 16 September 2020 (has links)
Eine Broschüre zum Thema: Erkennen rechtsextremistischer Symbole, Kennzeichen und Organisationen. Entstanden in einer Zusammenarbeit des Landesamtes für Verfassungsschutz Sachsen mit der Polizei Sachsen. Redaktionsschluss: 30.09.2019
129

Výpočet energetické dostatečnosti napájení tratí DPMB / The calculation of the adequacy of energy supply lines DPMB

Bednařík, Jaroslav January 2009 (has links)
This paper contains an introduction that describes the current situation of the problem and its energy supply improvement. It discusses everything from power substations to trolleys which are fed through sections. There is a reference to the network operating deficiencies and possible solutions. The second part describes the development of these networks and their modernization in a growing city. It is verified by calculation if were our considerations good and proposed network will be normally reliable and capable. The final part deals with the economic balance of the project and its various alternatives. Development of energy networks and facilities cost many finance and these investments do not show immediately. Future will be paid off because as soon the changes come less problems may occur.
130

Komunikační systém s rozprostřeným spektrem / Spread-spectrum Communication System

Machala, Pavel January 2012 (has links)
The thesis focuses on issues around communication system with the Direct Spread Spectrum Signal Signal. This work outlines the theoretical analysis of this technique and subsequently is created a communication system concept. The device concept is adjusted so that the device can be used as a laboratory device, presenting the spreading technique. This thesis offers a comprehensive and detailed description of the communication system construction, including design of transmitter, receiver and a common transmission channel. In conclusion are stated the results of devised communication system.

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