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

Motion of red blood cells in a glass microchannel: a global optimization approach

Este artigo também deve ser anexado ao Departamento Tecnologia Mecânica, docente Rui Alberto Madeira Macedo Lima.In this work we characterized the behavior of red blood cell motion through a glass microchannel. In this study we consider the radial displacement of forty red blood cells and use different functions to approximate the radial displacement of each of them, by means of global optimization using stretched simulated annealing method. Some numerical results are shown

Entrepreneurial Orientation and Dynamic Capabilities

Currently, small and medium enterprises that are family businesses (SMEFs) assume an important role in the global economy. Further, innovation and flexibility became vital to firms’ survival and prosperity in the market during these volatile times. Firms should not only possess critical resources, but also be able to recombine them. Characterized by resource restrictions, SMEFs can rely on dynamic capabilities to access resources and be competitive in the market. In this regard, networking capabilities (NC) and resource combinations (RC) such as exploitative and explorative product development and on market-related capabilities emerge as key dynamic capabilities. This chapter examines the role of Entrepreneurial Orientation (EO) on NC and RC. Using a qualitative method of in-depth case study, the chapter analyzes 12 Portuguese SMEFs.info:eu-repo/semantics/publishedVersio

Cell-free layer (CFL) analysis in a glass capillary: comparison between a manual and automatic method

In this study, in vitro blood flowing through a 100 m glass capillary was studied. The images were captured using a confocal system and post-processed using Image J and MatLab. The aim of the present work, was to measure the trajectories of the cell-free layer (CFL) by using two different methods, i. e., a manual method (MM) and an automatic method (AM). For theMM we have used amanual tracking plugin (MTrackJ) from Image J to track labeled red blood cells (RBCs) flowing around the boundary of the RBCs core. For the AM we have used a MatLab scripts to measure automatically the CFL trajectories. The preliminary numerical results suggest that the CFL trajectories follow a polynomial function for both methods.The authors acknowledge the financial support provided by: PTDC/SAU-BEB/108728/2008, PTDC/SAU-BEB/105650/2008, PTDC/EME-MFE/099109/2008 and PTDC/SAU-ENB/116929/2010 from the FCT (Science and Technology Foundation) and COMPETE, Portugal

Sex workers' narratives about clients with disabilities: can training improve sexual health in Portugal? = Narrativas de trabalhadores(as) do sexo sobre clientes com diversidade funcional: poderá a formação melhorar a saúde sexual em Portugal?

People with disabilities face barriers that limit their sexual lives. In Portugal, some individuals with physical impairments have shown interest in resorting to sexual assistance provided by trained professionals, according to the client’s preferences and needs. However, in Portugal, sex workers lacking any formal training represent the only way to access commercial sex services. Thus, this study analyzes the experiences of sex workers that provide services for disabled clients. The interviews of thirteen sex workers were analyzed using the thematic analysis method proposed by Braun and Clarke. The key findings show that men seek out sexual and emotional satisfaction from sex work. Additionally, specificities inherent to the lack of training and the relationships established tend to embarrass professionals. Finally, we conclude that training coupled with sexual education and popular awareness about gender differences in the pursuit of sex is fundamental to improve the sexual health of those who choose sex services as a way of sexual expression.info:eu-repo/semantics/publishedVersio

Uma Casa Portuguesa: as crianças austríacas em Portugal no pós-guerra (1947-1958)

Between 1947 and 1958, thousands of Austrian children were hosted by Portuguese families and institutions as part of an action promoted by Caritas. Thus escaping, for some time, the misery of a country devastated by war, these “Caritas children” found in Portugal, under Antonio de Oliveira Salazar’s Estado Novo, shelter and, in most cases, affection: an experience that, besides having repercussions in their memories and journeys, also left marks that, although less visible, continue to make themselves felt in Portugal. In this article we present a general outline of the research «The “Caritas Children”, between Austria and Portugal (1947-1958)», which was aimed to understand the way the Action took place, its repercussions on those involved, the way it was dealt with by government agencies and displayed by the press at its service and perceived by the population

Solid Waste Mixtures as Constructed Wetlands Filling: Effect of Hydraulic Loading Rate on Nutrient Removal from Wastewater

This study aims to contribute to constructed wetlands’ (CWs) eco-efficiency by applying the concepts of circular economy and waste to treat waste. Five sets of lab-scale CWs with different combinations of filling materials were evaluated and the effect of the hydraulic loading rate (HLR) on the nutrient removal efficiencies was studied. Each CW set consisted of two, duplicate, plastic pots with solid waste filling supporting Phragmites australis macrophyte plants. The filling materials were layer combinations of limestone rock fragments, a waste from construction activities, and one of four other solid wastes: cork granulates from the cork industry (LCG); snail shells from the food and catering industry (LSS); coal slag from coal power plants (LCS); and clay brick fragments from construction activities (LBF). A reference set (LO) was filled only with limestone fragments. The CWs were operated using a low-strength wastewater in successive fill-and-drain cycles with a retention time of one to eight days and a one-day rest. Their removal efficiency was evaluated for COD, total phosphorus (TP) and total nitrogen (TN). All four CWs with mixed filling showed COD removal efficiencies higher than the reference CW and above 79%. The highest removal efficiency was achieved by the LCS CW (91 to 97%). The reference LO CW showed the highest TP removal efficiency. With exception of the LSS CW, the mixed filling CWs showed removal efficiencies close to the reference CW (above 55%). All but the LSS CW showed higher TN removal efficiencies than the reference CW (above 51%). The observed effect of HLR depends on the type of CW. The effect on COD, TP and TN removal efficiencies averaged 9%, 15% and 20%, respectively, for a range of HLR from 0.005 to 0.087 m/day. From this study it can be concluded that all tested layer-packed mixed solid waste fillings are adequate substrate combinations for nutrient removal from wastewater. Moreover, high nutrient removal efficiencies were maintained over a wide range of hydraulic loading rates. This innovative combination of waste materials can improve the CW adaptability to specific types of wastewater and contribute to reducing solid waste disposal in landfills.This work was supported by Program FEDER, ref. POCI-01-0145-FEDER-023314, project VALORBIO. The authors acknowledge the collaboration of the Lab.IPT staff and the assistance of the Instituto Politécnico de Tomar maintenance staff.info:eu-repo/semantics/publishedVersio

Combination of various solid wastes with fragmented limestone as filler for constructed wetlands used for wastewater treatment

This study aims to contribute to the development of eco-efficient constructed wetlands through the concept of circular economy and the use of waste to treat waste Combinations of five solid wastes were evaluated as filler materials for CWs used for wastewater treatment To evaluate the combined capability of the waste materials to wastewater treatment, five sets of unplanted lab-scale CWs were established The CWs were operated in a discontinuous mode for three successive fill and drain cycles The highest COD removal rate was obtained for a CW filled with limestone and cork waste 90.3+/-0.9%. The highest total nitrogen removal rate was obtained for a CW filled with limestone and clay brick fragments 84.8+/-0.1%. Total phosphorus removal percentage of 91.8+/-0.1% was achieved for a control CW filled with limestone It was observed that layer packed solid waste combination fillings are adequate in improving COD removal in limestone based CWs, and that all but the limestone snail shells filling have a very good performance for total nitrogen and total phosphorus removal from wastewater.info:eu-repo/semantics/publishedVersio

Tracer experiments with lithium chloride to evaluate the hydrodynamics of constructed wetlands. Comparison of alternative analytical methods

The characterization of water flow dynamics (hydrodynamics) through constructed wetlands is relevant for optimizing wastewater treatment. Although constructed wetlands consist of simple systems, the water flow is complex and irregular, therefore, the study of hydrodynamics requires the use of experimental technics such as tracer experiments. To evaluate the effects of the use of three different analytical methods to compute the concentration of lithium chloride on the main hydrodynamics parameters, tracer experiments were conducted in ten independent lab-scale constructed wetlands. The concentration of lithium chloride in the output flow of the wetlands was calculated by flame photometry, electrical conductivity using a calibration curve and electrical conductivity using the salt molar conductivity. The paired samples T-test or the non-parametric Wilcoxon’s Signed-Ranks test were used to demonstrate that the computed hydraulic retention time and the number of tanks accordingly with the tanks-in-series model were not significantly affected by the selected analytical method.This work has been financially supported by FEDER grant COMPETE-01-0145-023342 to project VALORBIO. Authors acknowledge the support of BIOTEC.ipt and Lab.IPT and the work of Carlos Ferreira, Isabel Silva and Alcino Serras.info:eu-repo/semantics/publishedVersio