Aldo Ivan Céspedes Arce

Quantifying electrode position effects in EEG data with Lempel-Ziv complexity

Complexity measurement using Lempel and Ziv algorithm (LZ) has been used to analyze physiological data. This work shows that the Lempel and Ziv complexity measurement of EEG signals using wavelets transforms is independent of electrode position and dependent on cognitive tasks and brain activity. EEG database with 122 subjects from the public EEG dataset was used in this study. This database have spontaneous EEG and evoked potential (EP) data from a 64-multielectrode array under a variety of conditions collected at several centers in the United States, sponsored by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) project. Two experiments were performed with this database. The first experiment was to test the dependency of electrode positions into LZ complexity measures and the second experiment was to analyze if the LZ complexity was sensitive to the EEG acquired from control and alcoholic subjects. The results show that the complexity measurement is dependent on the changes of the pattern of brain dynamics and not dependent on electrode position.

Uma barreira vertical pode aumentar a vazão de grãos de arroz de um cilindro com furo no fundo

Theoretical and experimental models of pedestrian flux in highly concentrated places and panic situations have shown that a properly located obstacle in from of the exits could actually increase the evacuation velocity. Analogous experiences made with glass grains flowing out of a bi-dimensional rectangular silo also found that a circular disc obstacle close to the exit hole could facilitate the draining of the grains. In this work we develop a relatively simple tri-dimensional version of the problem above. We studied the flow of rice grains out of a cylinder with a hole at the bottom and a vertical barrier that divide equally the grains inside. For a given diameter (D) of the hole at the bottom of the cylinder we repeated the measurements with different thicknesses (b) and different initial heights (h) of the barrier. Our measurements confirmed that there is an optimal b and h that maximize the evacuation speed of the grains. On the other hand, an increase in D always produced and increase in the exit velocity of the grains. All results can be easily replicated in the classroom.

Noninvasive method to assess the electrical brain activity from rats

This research presents a noninvasive method for the acquisition of brain electrical signal in rat. Was used an electroencephalography (EEG) system developed for bovine and adapted to rats. The bipolar electrode system (needle electrodes) was glued on the surface of the head of the animal without surgical procedures and the other electrode was glued to the tail, as ground. The EEG activity was sampled at 120Hz for an hour. The accuracy and precision of the EEG measurement was performed using Fourier analysis and signal energy. For this, the digital signal was divided into sections successive of 3 seconds and was decomposed into four frequency bands: delta (0.3 to 4Hz), theta (4-8Hz), alpha (8-12Hz) and beta (12-30Hz) and energy (µV²) of the series of time filtered were calculated. The method allowed the acquisition of non-invasive electrical brain signals in conscious rats and their frequency patterns were in agreement with previous studies that used surgical procedures to acquire EEG in rats. This system showed accuracy and precision and will allow further studies on behavior and to investigate the action of drugs on the central nervous system in rats without surgical procedures.

MONITORIZACIÓN DE REBAÑOS DE BOVINOS A TRAVÉS DE REDES DE SENSORES INALÁMBRICOS

Se presenta el prototipo de un sistema proyectado utilizando tecnicas de instrumentacion electronica y tecnologia de comunicacion inalambrica pudiendo ser utilizado para recolectar datos fisiologicos y monitorizar rebanos de bovinos. La necesidad de desarrollar tecnicas de adquisicion de datos, que causen menos perturbaciones al comportamiento natural de los animales, de interes en la zootecnia de precision, fue la principal motivacion de este trabajo. Para probar la aplicabilidad de la tecnologia de las redes de sensores inalambricos en este campo, se construyo una infraestructura utilizando tecnicas de instrumentacion electronica y comunicacion por radio-frecuencia. La red fue proyectada con el protocolo floating base sensor network (FBSN) que implementa una topologia adhoc con seleccion aleatoria de nodos. Los prototipos construidos fueron utilizados para efectuar colectas de datos de la actividad electrica cerebral y temperatura corporal de seis novillas de raza Holandesa. A fin de optimizar la infraestructura, fue desarrollado un software que a partir de la simulacion del desplazamiento de un rebano bovino ayuda a determinar la mejor distribucion de esa infraestructura en el area monitorizada. Los resultados alcanzados mostraron que es posible utilizar redes de sensores inalambricas como tecnicas eficientes para obtener datos fisiologicos de bovinos.

Metabolite of tryptophan promoting changes in EEG signal and the oxidative status of the brain.

Tryptophan is an essential amino acid precursor of neurotransmitter serotonin and triptamine. During its metabolism, indole‐3‐acetic acid (IAA) is generated; this substance presents both antioxidant and prooxidant effects in different biological systems in addition to hipoglicemic effects. To date, electroencephalography (EEG) has been used to evaluate the temporal effect of several substances in neurotransmission. The goal of this study was to characterize the effect of IAA in the brain by analysing the EEG signal and evaluate the oxidative status by means of biochemical parameters. The EEG was acquired by using a noninvasive method, and the brain electric signal was analysed by advanced digital signal processing techniques to determinate the energy signal filtered in different band frequencies. Furthermore, the oxidative status of the brain was investigated by measuring the activity of antioxidant enzymes and lipid peroxidation as well as blood glucose rates of the animals treated with different doses of IAA. Our results showed the relationship of IAA administration with changes in EEG signals. The oxidative status of the brain was modified by IAA after 14 days of treatment. Copyright

Vazão de grãos em um silo cilíndrico: uma atividade experimental

In basic physics books practically anything is discussed about the flux of granular materials, even though grains systems are widely present in the everyday life. In this work was developed a relatively simple experimental system to study the flow of rice and sugar grains out of a cylindrical silo with a circular aperture at the bottom. Measurements were repeated at different diameters of the circular holes and different initial heights of the grains column. For didactic motivations, the same system was used to measure the flow of water. The results clearly illustrate the differences between the two kinds of fluids and can be easily replicated in the classroom.

Um modelo de gestão baseado em e-science e data warehouse para aplicação no agronegócio

O presente artigo tem como objetivo descrever um sistema de gestao aplicado a pecuaria, atraves do monitoramento e identificacao de animal a distância utilizando tecnicas de comunicacao sem fio. Este sistema permitira o acompanhamento do animal durante o seu ciclo de vida, permitindo ao gestor inclusive, coletar dados telemetricos em tempo real. Esta coleta podera ser realizada localmente ou atraves de um acesso a internet, facilitando assim o gerenciamento e controle de produtividade e qualidade animal, pois o sistema podera gerenciar determinados elementos, tais como: temperatura, tempo de descanso, tempo em alimentacao dentre outros, formando assim um grande banco de dados (data warehouse) que podera ser acessado por varios pesquisadores criando um sistema e-science.

Ensinando os fundamentos de redes de sensores sem fio usando um sistema simples

The electronic monitoring using wireless sensor network is a human knowledge that has boon investigated in order to improve their functional capabilities and incoming applications. This paper aim to present an educational system that able basic physics concept, concerned to the wireless sensor communications, to be more comprehensive.

A wireless data acquisition system for cattle behavior monitoring in zootechnics E-Science

portuguesEste artigo estuda a viabilidade de um sistema de monitoramento e coleta de dados atraves da WEB, com a construcao de um e-Science Zootecnico. Foram utilizadas tecnicas de modelagem orientada a objetos, linguagens de programacao php, C++, Java e banco de dados MySql para a elaboracao do ambiente compu- tacional. O sistema de hardware, o dispositivo eletronico de comunicacao e os protocolos de monitoramento foram desenvolvidos utilizando o protocolo Float Base Sensor Network e tecnicas de instrumentacao eletronica. Para testar o siste- ma desenvolvido, foi realizado um experimento com 6 animais da raca Holstein equipados com dispositivos de coleta de dados. O ambiente expe- rimental foi equipado com 6 antenas fixas e uma câmera IP. Os resultados obtidos mostraram a eficiencia do sistema de coleta e de recepcao dos dados atraves das antenas distribuidas na area. A metodologia usada no projeto, bem como os resultados do experimento, permitem concluir que o objetivo de gerenciar e monitorar o animal duran- te um experimento, com a coleta de dados telemetricos em tempo real foi alcancada, alem de possibilitar o deslocamento livre do animal durante a coleta dos dados. EnglishThis paper studies the feasibility of a system of monitoring and data collection via the web, with the construction of an e-Science Zootechnical. Object-oriented modelling techniques were used and programming languages: php, C++, Java and MySql database for development of the computing environment. The system hardware, electronic communication device, and monitoring protocols were developed using the Float Base Sensor Network Protocol and techniques of electronic instrumentation. To test the system, an experiment was conducted with six Holstein animals equipped with data collection devices. The experimental environment was equipped with six antennas and a fixed IP camera. The results showed the efficiency of the collection system and receiving data through the antennas distributed in the area. Considering the methodology used in the project, as well as the results of the experiment, is possible conclude that, with the telemetric data collection in real time, the management and monitoring the animal during an experiment can be done, in addition to allowing free movement of the animal during the data collection.

Uma análise de deslocamento de rebanho bovino através dos modelos random walk e browniano

The present article simulate the movement of bovine herd through the aleatory movements random walk and brownian, trying to analyze which of those predicts the movement better of bovine herd displacement, defining parameters and describing the algorithms used in both movements and using them in the construction of the events of the simulator. With the construction of the simulator it was possible the analysis of the movements, besides the understand that model of displacement better if apply of bovine herd displacement. Also it was possible an analysis of space acting for the construction of the location nets and identification of the herd through of wireless sensor network.