A complexa fisiopatologia dos episódios vasooclusivos na anemia falciforme

Hemolytic anemia and vasoocclusion are the cardinal clinical features of sickle cell anemia. Vasoocclusion is a complex process involving not only the polymerization of deoxygenated sickle hemoglobin tetramers, but also interactions between sickle erythrocytes, vascular endothelium, platelets, leukocytes, and plasma proteins. The increased adherence of sickle erythrocytes to endothelium has been implicated as an early step in vasoocclusion. Other researchers have focused on leukocytes and platelets which might also contribute to disturbed blood flow. Microvascular occlusion results in acute painful crises, whereas macrovascular occlusion seems to be the cause of organ failure. The anemia results from the markedly shortened circulatory survival of sickle erythrocytes, together with a limited erythropoietic response. The erythropoiesis increases intensively, but it is not enough to balance the increased rate of erythrocytes destruction to maintain normal levels of total erythrocytes and hemoglobin concentrations; mainly by the low oxygen affinity of hemoglobin S and increased 2,3-Diphosphoglycerate. It is very difficult to separate processes leading to anemia or to vasoocclusion. Understanding the involvement of multiple blood componentes in vasoocclusion may elucidate the clinical manifestations and complications of sickle cell anemia, and may give new insights into the preventive and curative therapy.

Development of an instrumentation system embedded on FPGA for real time measurement of mechanical vibrations in rotating machinery

The real-time monitoring of events in an industrial plant is vital, to monitor the actual conditions of operation of the machinery responsible for the manufacturing process. A predictive maintenance program includes condition monitoring of the rotating machinery, to anticipate possible conditions of failure. To increase the operational reliability it is thus necessary an efficient tool to analyze and monitor the equipments, in real-time, and enabling the detection of e.g. incipient faults in bearings. To fulfill these requirements some innovations have become frequent, namely the inclusion of vibration sensors or stator current sensors. These innovations enable the development of new design methodologies that take into account the ease of future modifications, upgrades, and replacement of the monitored machine, as well as expansion of the monitoring system. This paper presents the development, implementation and testing of an instrument for vibration monitoring, as a possible solution to embed in industrial environment. The digital control system is based on an FPGA, and its configuration with an open hardware design tool is described. Special focus is given to the area of fault detection in rolling bearings. © 2012 IEEE.

Aplicação de redes neurais artificiais na predição de diâmetro e rugosidade durante o processo de furação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo e caracterização do processo de usinagem do compóstio GLARE

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utilização de diferentes métodos de lubri-refrigeração na retificação cilíndrica externa de mergulho de cerâmica avançada com rebolo diamantado

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Genotipagem de leveduras presentes no processo industrial de produção de álcool combustível e estudo do polimorfismo de genes envolvidos no processo fermentativo em Saccharomyces cerevisiae

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento de um sistema de instrumentação de medição de vibração mecânica em máquina rotativas, em tempo real, embarcado em FPGA

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Experimental RTM manufacturing analysis of carbon/epoxy composites for aerospace application

The success of manufacturing composite parts by liquid composite molding processes with RTM depends on tool designs, efficient heat system, a controlled injection pressure, a stabilized vacuum system, besides of a suitable study of the preform lay-up and the resin system choice. This paper reports how to assemble a RTM system in a laboratory scale by specifying heat, injection and vacuum system. The design and mold material were outlined by pointing out its advantages and disadvantages. Four different carbon fiber fabrics were used for testing the RTM system. The injection pressure was analyzed regarding fiber volume content, preform compression and permeability, showing how these factors can affect the process parameters. The glass transition temperature (Tg) around 203 ºC matched with the aimed temperature of the mold which ensured good distribution of the heat throughout the upper and lower mold length. The void volume fraction in a range of 2% confirmed the appropriate RTM system and parameters choice.

Evaluation of different methods of cooling-lubrication in cylindrical grinding of advanced ceramic dip

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Aspectos da furação do titânio 6Al4V com broca de aço rápido sinterizado e broca de metal duro

Pós-graduação em Engenharia Mecânica - FEG

Estudo da tecnologia e processos de extração em poços de petróleo

The analysis of the extraction process in oil wells is presented exploring the challenges to the effectiveness of the procedure is shown step by step in the process. There is an analysis of the major tools and equipment needed in the drilling process, promoting the understanding of the challenges in the pre-salt layers, compared to conventional processes. The work is reinforced through studies of the influence of the corrosive compared not corrosive environment in drill strings

Online analysis of H2S and SO2 via advanced mid-Infrared gas sensors

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Concepção detalhada de uma bancada para simular esforços mecânicos em colunas de perfuração

In this work we study the construction of a test rig made to simulate the Mechanical efforts in wich a drillstring is submitted. The model is based on the rig built at IDS, Germany. There are some fault liabilities while doing the project of the axis. Therefore it's important to analyze and take knowledge of this efforts in order to predict failures like rupture or fatigue collapse. The main objective of this theis is to show the operating principle of the test rig and it's construction. The accomplished study allow us to predict the drillstring behavior and from the economic point of view that is very important because failures results in equipments maintenance that requires time and money causing prejudice to the company. Using SolidWorks, a simulation software, the thesis approaches all the mechanical parts required for it's construction as well as it's working principle. Acquisition sensors like strain gauges, accelerometer, and torque transductor were also used in this model. The objective of this thesis is to create a simulation model to be eventually at FEG(UNESP). During the development of the study, it was possible to learn more about the drilling process and the mechanical efforts in which the drill pipe is submitted. The accomplished contributed with knowledge for the student in the drilling process area. Also during the development of the study it was possible to have contact with different areas of engineering but the study is specifically directed to the construction of the test rig. Therefore the main theme of this thesis is to show the operating principle of the test rig and it's construction

In-process grinding monitoring by acoustic emission

This work aims to investigate the efficiency of digital signal processing tools of acoustic emission signals in order to detect thermal damages in grinding process. To accomplish such a goal, an experimental work was carried out for 15 runs in a surface grinding machine operating with an aluminum oxide grinding wheel and ABNT 1045. The acoustic emission signals were acquired from a fixed sensor placed on the workpiece holder. A high sampling rate data acquisition system at 2.5 MHz was used to collect the raw acoustic emission instead of root mean square value usually employed. Many statistics have shown effective to detect burn, such as the root mean square (RMS), correlation of the AE, constant false alarm (CFAR), ratio of power (ROP) and mean-value deviance (MVD). However, the CFAR, ROP, Kurtosis and correlation of the AE have been presented more sensitive than the RMS.

Evaluation of Laser Fluorescence in the Monitoring of the Initial Stage of the De-/Remineralization Process: An in vitro and in situ Study

This study aimed to evaluate laser fluorescence (LF) for monitoring the initial stage of subsurface de- and remineralization (<150 mu m depth). Ninety-six sound blocks of bovine enamel, selected according to surface hardness (SH) and LF were used in two experimental studies, in vitro and in situ. In vitro, blocks were exposed to a demineralizing solution, then remineralized by pH cycling for 6 days. In situ, 10 volunteers wore acrylic palatal appliances, each containing 4 dental enamel blocks that were demineralized for 14 days by exposure to 20% sucrose solution. Following this treatment, blocks were submitted to remineralization for 1 week with fluoride dentifrice (1,100 mu g F/g). In both experiments, SH and LH were measured after demineralization and after remineralization. Further, enamel blocks were selected after the demineralization/remineralization steps for measurement of cross-sectional hardness and integrated loss of subsurface hardness (Delta KHN). SH and Delta KHN showed significant differences among the phases in each study. LF values for sound, demineralized and remineralized enamel were: 5.2 +/- 1.1, 8.1 +/- 1.2 and 5.6 +/- 0.8, respectively, in the in vitro study, and 5.3 +/- 0.3, 16.5 +/- 4.7 and 6.5 +/- 2.5, respectively, in the in situ study, values for demineralized enamel being significantly higher than for sound and remineralized enamel in both studies. However, LF was correlated with Delta KHN only in situ. LF was capable of monitoring de- and remineralization in early lesions in situ, when bacteria are presumably present in the caries lesion body, but is not correlated with mineral changes in bacteria-free systems. Copyright (C) 2009 S. Karger AG, Basel