Modelação matemática da camada de plasma em microcanais

Neste estudo apresenta-se uma proposta de modelação matemática da camada de plasma observada em escoamentos sanguíneos. Numa fase inicial, a resolução do problema fez uso da otimização não linear para encontrar o modelo matemático que minimiza o erro quadrático não linear entre o modelo e os dados numéricos que caracterizam a camada de plasma. Para tal, foram testados os algoritmos Simulated Annealing, Pattern Search, Algoritmo Genético e Quasi-Newton. Neste estudo conclui-se que o método de otimização que obteve melhores resultados foi o Algoritmo Genético. Também foi possível concluir que o melhor modelo para aproximar os dados numéricos que caracterizam a camada de plasma presente em escoamentos sanguíneos é baseado na soma de funções trigonométricas.Os autores agradecem à FCT, COMPETE, QREN e União Europeia (FEDER) no âmbito dos projetos PTDC/SAU-ENB/116929/2010 e EXPL/EMS-SIS/2215/2013.info:eu-repo/semantics/publishedVersio

Red blood cells motion in a glass microchannel

The motion of the red blood cells (RBCs) flowing in microvessels and microchannels depend on several effects, such as hematocrit (Hct), geometry, and temperature. According to our knowledge, the effect of the temperature on RBC motion was never investigated at a microscale level. Hence, the aim of the present work is to determine the effect of the temperature on the RBC’s trajectories and to investigate the best approximation of the trajectories through a nonlinear optimization. In vitro human blood was pumped through a 100 mm circular microchannel and by using a confocal micro- PTV system the RBC’s trajectories were measured at different temperatures, i.e., 25◦C and 37◦C. In this study we measured the motion of forty cells flowing in the middle of the microchannel and applied different functions to approximate its behavior.This study was supported in part by the following grants: Grant-in-Aid for Science and Technology (PTDC/SAU-BEB/108728/2008, PTDC/SAU-BEB/105650/2008 and PTDC/EME-MFE/099109/2008) from the Science and Technology Foundation (FCT) and COMPETE, Portugal

Analysis of the cell-free layer in a circular microchannels: trajectories of labeled red bllod cells

In this experimental work, we measure the trajectories of the cell-free layer (CFL) by tracking labeled red blood cells (RBCs) flowing around the boundary of the RBCs core. The circular glass microchannels studied are 100 um in diameter. The images are captured using confocal system and are post-processed using Image J and MATLAB. The results suggest that the trajectories follows a polynomial function

Cell-free layer measurements in bifurcating microchannels: a global approach

In the present work, in vitro blood flowing through bifurcating microchannels was studied, with the aim of characterizing the cell-free layer (CFL). The original images were obtained by means of a high-speed video microscopy system and then processed in MatLab using the Image Processing Toolbox. The numerical data was obtained automatically and analyzed by optimization techniques using the genetic algorithm approach. The results suggest that the CFL were formed in a similar way at the upper and lower regions in all bifurcations, and the measurements can be approximated through a sum of trigonometric functions

Deciphering the role of Staphylococcus aureus in Pseudomonas aeruginosa adaptation to cystic fibrosis lungs: bystander or intervener?

Microbiotec'17 - Congress of Microbiology and Biotechnology 2017Background: Pseudomonas aeruginosa is the major responsible for the high mortality rate of cystic fibrosis (CF) patients due to the development of chronic infections. To long persist, P. aeruginosa uses sophisticated mechanisms to achieve fulladaptation, mainly triggered by the harsh environmental conditions of CF lungs. The influence of Staphylococcus aureus, a primary colonizer of CF lungs, in increasing P. aeruginosa pathogenicity has also been reported. The main objective of this study was to decipher the impact of S. aureus on P. aeruginosa pathogenicity using in vitro conditions mimicking CF lungs. [...]This study was supported by the FCT (UID/BIO/04469/2013), COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Breast cancer: biomarkers and biosensors

This study was supported by the Portuguese Foundation for Science and Technology ( under the scope of the strategic funding of UID/BIO/ 04469 2020 unit and BioTecNorte operation (NORTE 01 0145 FEDER 000004 funded by the European Regional Development Fund under the scope of Norte 2020 Programa Operacional Regional do Norte Ana Cláudia Pereira is recipient of fellowships supported by a doctoral advanced training (call NORTE 69 2015 15 funded by the European Social Fund under the scope of Norte 2020 Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio