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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.
11

Padronização da análise dos produtos da PCR/RFLP que amplifica os genes Ribossomal Internal transcribed spacer (ITS) e Glucose-6- phosphate dehydrogenase (G6PD) para identificação de Leishmania spp. em gel de poliacrilamida / Standardization of PCR / RFLP product analysis that amplifies the Ribosomal Internal Transcribed spacer (ITS) and Glucose- 6-phosphate dehydrogenase (G6PD) genes for identification of Leishmania spp. in polyacrylamide gel

Marques, Cálita Pollyanna 30 August 2017 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-09-21T20:25:51Z No. of bitstreams: 2 Dissertação - Cálita Pollyanna Marques - 2017.pdf: 1468493 bytes, checksum: 90300902d8a48fc5600761dfccf90324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-22T11:43:21Z (GMT) No. of bitstreams: 2 Dissertação - Cálita Pollyanna Marques - 2017.pdf: 1468493 bytes, checksum: 90300902d8a48fc5600761dfccf90324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-22T11:43:21Z (GMT). No. of bitstreams: 2 Dissertação - Cálita Pollyanna Marques - 2017.pdf: 1468493 bytes, checksum: 90300902d8a48fc5600761dfccf90324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-30 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / American Cutaneous Leishmaniasis (LTA) is caused by protozoa of the genus Leishmania and it attacks the skin and/or mucous membranes. It is an endemic zoonosis in Brazil being notified in all the Regions. There is a relation between the species of parasite and the clinical manifestations, contributing to the diagnostic complexity, which up to the present, did not exist species-specific diagnosis. In the present work, the proposal was to standardize the analysis of the PCR/RFLP products to the ITS and G6PD genes in polyacrylamide gel. In order to standardize PCR/RFLP analysis on the ITS and G6PD genes, DNA from the reference Leishmania spp. Sample was used and 5%, 6%, 7% 8% and 10% polyacrylamide were tested. The protocol design considered the size of the amplicons generated by the PCR / RFLP, correlating the concentration of the polyacrylamide. To standardize the electrophoresis time the migration of the dyes used in the DNA sample buffer was monitored. To validate the technique, we selected 521 samples from Tocantins patients fixed on slides and 43 samples of parasite isolates stored in Leishbank. The samples from the patients from Tocantins were analyzed by PCR/RFLP to the kDNA and were selected to those positive for the validation. The concentration of the matrix for analysis of the PCR and RFLP products to the ITS gene was standardized in 6% and 8%, respectively, and distinguished the species L. (L.) amazonensis, but the species L. (V.) braziliensis, L. (V.) guyanensis and L. (V.) lainsoni were not distinguished among themselves, occurring the same between L. (V.) naiffi and L. (V.) shawi. The concentration of the matrix for analysis of the PCR products to the G6PD gene was standardized in 6% and distinguished L. (V.) braziliensis from the others. The validation of the polyacrylamide gel analysis of the PCR products to the ITS target from samples of patients fixed in slides was not performed, since of the 256 samples analyzed only 4 amplified. The validation of the analysis of the products of the PCR to the G6PD target in polyacrylamide gel from 48 samples fixed in slides characterized 81% as L. (V.) braziliensis and, characterized 63% of the isolates of parasites as L. (V.) braziliensis. The PCR/RFLP analyzes performed to discriminate Leishmania spp. are complementary and thus contribute to the species-specific diagnosis of LTA. / A Leishmaniose Tegumentar Americana (LTA) é causada por protozoários do gênero Leishmania e acomete pele e/ou mucosas. É uma zoonose endêmica no Brasil sendo notificada em todas as Regiões. Há uma relação entre a espécie de parasito e as manifestações clínicas, contribuindo à complexidade diagnóstica, que até o presente, não existi o diagnóstico espécie-específico. No presente trabalho, a proposta foi padronizar a análise dos produtos da PCR/RFLP aos genes ITS e G6PD em gel de poliacrilamida. Para padronizar as análises dos produtos da PCR/RFLP aos genes ITS e G6PD, foram utilizadas DNA da amostra de Leishmania spp., de referência, sendo testada a poliacrilamida na concentração de 5%, 6%, 7% 8% e 10%. O delineamento do protocolo considerou o tamanho dos amplicons gerados pela PCR/RFLP, correlacionando-o a concentração da poliacrilamida. Para padronizar o tempo da eletroforese foi monitorada a migração dos corantes usados no tampão da amostra de DNA. Para validar a técnica, foram selecionadas 521 amostras de pacientes tocantinenses fixadas em lâminas e 43 amostras de isolados de parasitos armazenados no Leishbank. As amostras dos pacientes tocantinenses foram analisadas pela PCR/RFLP ao kDNA e foram selecionadas àquelas positivas para a validação. A concentração da matriz para analise dos produtos da PCR e RFLP ao gene ITS ficou padronizada respectivamente em 6% e 8% e distinguiu a espécie L.(L.) amazonensis, porém as espécies L. (V.) braziliensis, L. (V.) guyanensis e L. (V.) lainsoni não foram distinguidas entre si, ocorrendo o mesmo entre L. (V.) naiffi e L. (V.) shawi. A concentração da matriz para analise dos produtos da PCR ao gene G6PD ficou padronizada em 6% e distinguiu L. (V.) braziliensis das demais. A validação da análise em gel de poliacrilamida dos produtos da PCR ao alvo ITS a partir de amostras de pacientes fixadas em lâminas não ser realizada, pois das 256 amostras analisadas somente 4 amplificaram. A validação da análise dos produtos da PCR ao alvo G6PD em gel de poliacrilamida a partir de 48 amostras fixadas em lâminas caracterizou 81% como L. (V.) braziliensis e, caracterizou 63% dos isolados de parasitos como L. (V.) braziliensis. As análises pela PCR/RFLP realizadas para discriminar Leishmania spp. se complementam e, assim, contribuem para o diagnóstico espécie-específico da LTA.
12

Estado actual de la degradación de suelos calizos en varias zonas de la Región de Murcia

Tudela Serrano, Mª Luz 17 July 1993 (has links)
Se presenta una propuesta metodológica de clasificación de la degradación del suelo en ecosistemas semiáridos por pérdida de materia orgánica, basada en el tratamiento estadístico por análisis discriminante y factorial de los parámetros que habitualmente se determinan en los suelos y que influyen de manera decisiva en su degradación biológica y física. Se aplica el estudio a suelos calizos de siete zonas de la Región de Murcia, obteniéndose tres elementos discriminatorios: materia orgánica, textura y clase de productividad, siendo las dos primeras las de mayor peso específico. Con el análisis discriminante se establecen cuatro clases de degradación de suelos, en función del contenido en materia orgánica. A continuación, para evaluar el estado de degradación del suelo se recurre al análisis factorial de las variables estudiadas, presentando los suelos menos degradados un factor fertilidad positivo, mientras que los más degradados tienen un factor fertilidad negativo, tanto más bajo cuanto más intensa es la degradación. Como conclusión, se considera que el Calcisol pétrico, cultivado, procede de la degradación del Kastanosem pétrico, bajo vegetación natural, por degradación biológica de éstos, con la consiguiente disminución de materia orgánica con el transcurso del tiempo. Se calcula que dicha degradación viene operando desde hace unos 100 años. / We presented/displayed in this work a methodologic proposal of classification of the degradation of the ground in semi-arid ecosystems by loss of organic matter, cradle in the statistical treatment by discriminante and factorial analysis of the parameters that habitually determine in grounds and that they influence of decisive way in its biological and physical degradation. It is applied to the study to limestone grounds of seven zones of the Region of Murcia, obtaining itself three discriminatory elements: organic matter, texture and class of productivity, being two first those of greater specific weight. With the discriminante analysis four classes of ground degradation settle down, based on the content in organic matter, of greater to minor, assigning each sample to one of them. Class 1: Calcic Kastanosem, Leptosol and Cambisol. Class 2: Pétrico Kastanosem. Class 3: Pétrico and háplico Calcisol. Class 4: Regosol, Fluvisol and Antrosol. Next, to evaluate the state of degradation of the ground one resorts to the factorial analysis of the studied variables, presenting grounds less degraded a factor positive fertility, whereas the most degraded they have a negative factor fertility, lower as much at the most intense is the degradation. Like conclusion, it is considered that the pétrico Calcisol, cultivated, comes from the degradation of the pétrico Kastanosem, under natural vegetation, by biological degradation of these, with the consequent diminution of organic matter with the course of the time. One calculates that this degradation has been coming operating for about 100 years.
13

Metabolomic comparison of selected Helichrysum species to predict their antiviral properties

Heyman, Heino Martin 23 July 2010 (has links)
From the Helichrysum genus 600 species occur in Africa of which 244 species are found in South Africa. The most commonly used Helichrysum species for medicinal purposes are H. cymosum, H. odoratissimum, H. petiolare and H. nudifolium. The medicinal uses include the treatment of coughs, colds, fever, infection, headaches, menstrual pain and are very popular for wound dressing. Previous published research has shown that H. aureonitens has antiviral properties against Herpes simplex virus type 1 (HSV-1). In this study, further investigation into the Helichrysum species was undertaken, to establish the active constituents responsible for anti-HSV activity using a metabolomics approach. The cytotoxicity of 12 Helichrysum species was investigated and ranged from <3.125 μg/ml to 277.8 μg/ml on the vero cell line. The 12 Helichrysum species also showed various levels of antiviral activity against HSV, with both the water-methanol and chloroform extracts of H. adenocarpum subsp. adenocarpum being the most active extract at 25 μg/ml. In this study the activity of Helichrysum species against HIV-1 RT was also investigated. Helichrysum populifolium was the most active extract, inhibiting the HIV-1 RT enzyme by 63.78 % at 200 μg/ml. The bioactivity data and the spectral nuclear magnetic resonance (NMR) data of al the Helichrysum species from this study was analysed using the SIMCA-P software to discriminate between the different species on the basis of their bioactivity and chemical composition. The samples did not group well on Principal Component Analysis (PCA) but did separate well using the Orthogonal Projection to Latent Structure – Discriminate Analysis (OPLS-DA) on the basis of their activity and NMR spectra data. From the OPLS scoring plots analysis, contribution plots were created which indicated regions responsible for the difference between the species, with these regions being investigated to identify the bioactive constituents. It was thus possible to use metabolomics to discriminate between samples on the basis of their activity and show that it could probably be used in future as a tool to identify active ingredients in medicinal plants and accelerate drug discovery. Copyright / Dissertation (MSc)--University of Pretoria, 2009. / Plant Science / unrestricted
14

The phenomenon of Xenophobia as experienced by immigrant learners in inner city schools of Johannesburg

Osman, Razia 11 1900 (has links)
There has been a significant increase in immigrant learners in South African schools. This research study captures the experiences of immigrant learners in selected inner city schools of Johannesburg. The May 2008 xenophobic violence prompted the researcher to investigate the extent of xenophobia. A survey of immigrant learners, South African learners and educators was conducted by means of interviews that allowed the research participants to express their feelings and experiences regarding the phenomenon of xenophobia. The result of the study revealed that immigrant learners do experience xenophobia in various forms by South African learners and, in some cases, educators as well. Immigrant learners were predominantly exposed to prejudice and xenophobic comments. They perceived South Africa as positive, giving them hope and opportunities. This research provided a baseline for more extensive research into this phenomenon. / Thesis (M. Ed. (Guidance and Counselling)
15

The phenomenon of Xenophobia as experienced by immigrant learners in inner city schools of Johannesburg

Osman, Razia 11 1900 (has links)
There has been a significant increase in immigrant learners in South African schools. This research study captures the experiences of immigrant learners in selected inner city schools of Johannesburg. The May 2008 xenophobic violence prompted the researcher to investigate the extent of xenophobia. A survey of immigrant learners, South African learners and educators was conducted by means of interviews that allowed the research participants to express their feelings and experiences regarding the phenomenon of xenophobia. The result of the study revealed that immigrant learners do experience xenophobia in various forms by South African learners and, in some cases, educators as well. Immigrant learners were predominantly exposed to prejudice and xenophobic comments. They perceived South Africa as positive, giving them hope and opportunities. This research provided a baseline for more extensive research into this phenomenon. / Thesis (M. Ed. (Guidance and Counselling)
16

Numerical Evaluation of Classification Techniques for Flaw Detection

Vallamsundar, Suriyapriya January 2007 (has links)
Nondestructive testing is used extensively throughout the industry for quality assessment and detection of defects in engineering materials. The range and variety of anomalies is enormous and critical assessment of their location and size is often complicated. Depending upon final operational considerations, some of these anomalies may be critical and their detection and classification is therefore of importance. Despite the several advantages of using Nondestructive testing for flaw detection, the conventional NDT techniques based on the heuristic experience-based pattern identification methods have many drawbacks in terms of cost, length and result in erratic analysis and thus lead to discrepancies in results. The use of several statistical and soft computing techniques in the evaluation and classification operations result in the development of an automatic decision support system for defect characterization that offers the possibility of an impartial standardized performance. The present work evaluates the application of both supervised and unsupervised classification techniques for flaw detection and classification in a semi-infinite half space. Finite element models to simulate the MASW test in the presence and absence of voids were developed using the commercial package LS-DYNA. To simulate anomalies, voids of different sizes were inserted on elastic medium. Features for the discrimination of received responses were extracted in time and frequency domains by applying suitable transformations. The compact feature vector is then classified by different techniques: supervised classification (backpropagation neural network, adaptive neuro-fuzzy inference system, k-nearest neighbor classifier, linear discriminate classifier) and unsupervised classification (fuzzy c-means clustering). The classification results show that the performance of k-nearest Neighbor Classifier proved superior when compared with the other techniques with an overall accuracy of 94% in detection of presence of voids and an accuracy of 81% in determining the size of the void in the medium. The assessment of the various classifiers’ performance proved to be valuable in comparing the different techniques and establishing the applicability of simplified classification methods such as k-NN in defect characterization. The obtained classification accuracies for the detection and classification of voids are very encouraging, showing the suitability of the proposed approach to the development of a decision support system for non-destructive testing of materials for defect characterization.
17

Numerical Evaluation of Classification Techniques for Flaw Detection

Vallamsundar, Suriyapriya January 2007 (has links)
Nondestructive testing is used extensively throughout the industry for quality assessment and detection of defects in engineering materials. The range and variety of anomalies is enormous and critical assessment of their location and size is often complicated. Depending upon final operational considerations, some of these anomalies may be critical and their detection and classification is therefore of importance. Despite the several advantages of using Nondestructive testing for flaw detection, the conventional NDT techniques based on the heuristic experience-based pattern identification methods have many drawbacks in terms of cost, length and result in erratic analysis and thus lead to discrepancies in results. The use of several statistical and soft computing techniques in the evaluation and classification operations result in the development of an automatic decision support system for defect characterization that offers the possibility of an impartial standardized performance. The present work evaluates the application of both supervised and unsupervised classification techniques for flaw detection and classification in a semi-infinite half space. Finite element models to simulate the MASW test in the presence and absence of voids were developed using the commercial package LS-DYNA. To simulate anomalies, voids of different sizes were inserted on elastic medium. Features for the discrimination of received responses were extracted in time and frequency domains by applying suitable transformations. The compact feature vector is then classified by different techniques: supervised classification (backpropagation neural network, adaptive neuro-fuzzy inference system, k-nearest neighbor classifier, linear discriminate classifier) and unsupervised classification (fuzzy c-means clustering). The classification results show that the performance of k-nearest Neighbor Classifier proved superior when compared with the other techniques with an overall accuracy of 94% in detection of presence of voids and an accuracy of 81% in determining the size of the void in the medium. The assessment of the various classifiers’ performance proved to be valuable in comparing the different techniques and establishing the applicability of simplified classification methods such as k-NN in defect characterization. The obtained classification accuracies for the detection and classification of voids are very encouraging, showing the suitability of the proposed approach to the development of a decision support system for non-destructive testing of materials for defect characterization.
18

The state application of repressive and reconciliatory tactics in the North Caucasus (2007-2014)

Zhirukhina, Elena January 2017 (has links)
This thesis was inspired by the question of how the state addresses irregular challenges for its survival and reputation. It used an example of the confrontation between illegal armed groups (IAGs) operating in the North Caucasus and the Russian state in 2007-2014. Investigation started by asking to what extent do repressive and reconciliatory counter tactics decrease the level of violence produced by illegal armed groups? The thesis was situated in-between of deterrence and backlash theories to examine (in)effectiveness of repressive and reconciliatory policies. It accounted for (in)effectiveness by investigating whether the policy decreases or increases the level of insurgency-related violence; namely, whether it causes deterrence or backlash, in the case of repression or, alternatively, whether it causes conformity or backlash in the case of reconciliation. The thesis operationalised its main variables by disaggregating the strategy into separate repressive and reconciliatory tactics. It considered, on the one hand, three types of IAGs tactics: armed assault, bombings (suicide bombing, vehicle bomb, bomb placement, bomb tossing, firing, fake bomb) and hostage taking. One the other hand, the state tactics were divided into four categories: repressive indiscriminate (regime of counterterrorist operation, clash, and shelling), repressive discriminate (special operation, shooting, arrest, seizure, and detection), reconciliatory indiscriminate (involvement of civil society through dialogue, and socio-economic development), and reconciliatory discriminate (amnesty and reintegration). The thesis expected targeted repressive operations to suppress active IAGs members, whereas socio-economic incentives to contribute to maintaining the success of violent repressive operations. To test these hypotheses, the thesis relied on large empirical data, specially collected from the open sources, including 3270 episodes of IAG-initiated violence and 6114 governmental repressive actions. Data for reconciliatory efforts was taken from official statistics. The thesis used a generalized linear negative binomial and a generalized additive negative binomial model to assess the relationship between governmental policies and the level of violence. The thesis found that discriminate violence does indeed decrease attacks. However, it causes an immediate strong backlash effect at first, and only with considerable time and magnitude of repression eventually leads to the reduction of violence. The more discriminate repression is applied the less backlash it causes. Unlike repression, reconciliatory tactics produce a decrease in attacks. Thus, the thesis found partial support for both deterrence and backlash models. It, however, showed that deterrence effect overcomes initial backlash reaction.
19

Využití prvků hodnotového inženýrství pro realizaci vybrané stavby v obci / Use of value engineering elements for realization of building in the municipality

Chytková, Markéta January 2012 (has links)
The aim of my thesis Use of value engineering elements for the realization of buildings in the municipality is to compare the evaluation methods of procurement in municipality and evaluation methods using elements of value engineering. A tender for reconstruction Šubertovo square was realized in the city Dobruška. In the thesis is shown way of evaluation of competing offers of the city Dobruška itself in sublimit simplified procedure and evaluation of competing offers by selecting more evaluation criteria and selecting the best offer with the highest degree of effectiveness.
20

Uma contribuição ao problema de detecção de ruídos impulsivos para power line communication

Lopez, Paola Johana Saboya 03 June 2013 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-04-24T15:28:35Z No. of bitstreams: 1 paolajohanasaboyalopez.pdf: 1042873 bytes, checksum: a46dd95de00e062cba39ef4b9b642462 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-04-24T17:09:24Z (GMT) No. of bitstreams: 1 paolajohanasaboyalopez.pdf: 1042873 bytes, checksum: a46dd95de00e062cba39ef4b9b642462 (MD5) / Made available in DSpace on 2017-04-24T17:09:24Z (GMT). No. of bitstreams: 1 paolajohanasaboyalopez.pdf: 1042873 bytes, checksum: a46dd95de00e062cba39ef4b9b642462 (MD5) Previous issue date: 2013-06-03 / A presente dissertação tem por objetivo propor e avaliar cinco técnicas de detecção de ruídos impulsivos para a melhoria da transmissão digital de dados via redes de energia elétrica (do inglês, Power Line Communications) (PLC). As técnicas propostas contemplam a detecção de ruídos impulsivos no domínio do tempo discreto, no domínio da transformada wavelet discreta (do inglês, Discrete Wavelet Transform) (DWT) e no domínio da transformada discreta de Fourier (do inglês, Discrete Fourier Transform) (DFT). Tais técnicas fazem uso de métodos de extração e seleção de características, assim como métodos de detecção de sinais baseados na teoria de Bayes e redes neurais. Análises comparativas explicitam as vantagens e desvantagens de cada uma das técnicas propostas para o problema em questão, e ainda indicam que estas são bastante adequadas para a solução do mesmo. / This dissertation aims to propose and evaluate five techniques for impulsive noise detection in order to improve digital communications through power line channels. The imput signals for the proposed detection techniques are impulsive noise signals on discrete-time domain, on the Discrete Wavelet Transform domain and on the Discrete Fourier Transform domain and it makes use of feature extraction and selection techniques, as well as detection techniques supported on Bayes Theory and Multi-layer Perceptron Neural Networks. Comparative analysis show some advantages and disadvantages of each proposed technique and the relevance of them to solve the impulsive noise detection problem.

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