Banca de QUALIFICAÇÃO: MARFRAN CLAUDINO DOMINGOS DOS SANTOS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARFRAN CLAUDINO DOMINGOS DOS SANTOS
DATE: 24/05/2022
TIME: 08:00
LOCAL: google meet
TITLE:

Application of infrared and molecular fluorescence spectroscopy together with multivariate analysis techniques in the detection of arboviruses in Aedes aegypti mosquitoes and clinical samples.

KEY WORDS:

Arbovirus detection. Entomological surveillance. Molecular Fluorescence Spectroscopy. NIR spectroscopy. Multivariate classification.

PAGES: 90
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Métodos Óticos de Análise
SUMMARY:

Significant attempts are being made worldwide to develop efficient tools for better prevention and clinical management of virus cases. The objective of this work was to evaluate the application of first and second orders spectroscopic techniques in the detection of arboviruses in Aedes aegypti mosquitoes and clinical samples. In the described studies, on this thesis, molecular fluorescence spectroscopy was applied together with the multivariate analysis techniques PARAFAC-LDA, PARAFAC-QDA, and N-PLSDA, as a new sensitive, specific, fast, simple methodology capable of identifying spectral variations between clinical samples with and without dengue and chikungunya viruses. To get this, Excitation-Emission Matrix (EEM) of 26 samples for each class (healthy x dengue x chikungunya) were used, totaling 78 samples. The samples were divided into training and test sets and, after building the models, the results were analyzed based on calculations of accuracy, sensitivity, specificity, and F-score. It was observed that the most efficient model in the classification work was the PARAFACQDA, obtaining the maximum value for all the calculated figures. PARAFAC-LDA and NPLS-DA also achieved encouraging results. The loadings captured in PARAFAC were provided and can be used in future studies to prove the relationship (or not) of the spectral data with the presence of viruses. In another study, infrared spectra (NIR and MIR) were used together with the SPA and GA variable selection algorithms, to select wave numbers capable of discriminating female Aedes, aegypti mosquitoes infected with dengue from uninfected mosquitoes. For this, SPA-LDA and GA-LDA models were constructed for the two techniques (NIR and ATR-FTIR). The built models were evaluated based on sensitivity and specificity calculations, and it was observed that for both SPA-LDA and GA-LDA, the models based on NIR spectra obtained better classification values, reaching 82.65 % of sensitivity and specificity for NIR-SPA-LDA; and 100.00 % for sensitivity and specificity for NIR-GA-LDA. Finally, it was observed that EEM matrices have the potential, soon, to be used as screening or diagnosis of arboviruses, having advantages when compared to more conventional techniques, and it was demonstrated that in the future we will be able to rely on portable NIR instruments at work of entomological surveillance and prediction of future dengue outbreaks.

BANKING MEMBERS:
Externo ao Programa - 1913849 - EDGAR PERIN MORAES
Interno - 1803692 - FABRICIO GAVA MENEZES
Presidente - 1714946 - KASSIO MICHELL GOMES DE LIMA
Interna - 1805556 - LUCIENE DA SILVA SANTOS