Improvement Of EEG Signal Recording With Non-Contact Electrodes In An Headset System

This paper presents methods in recording satisfactory EEG signals using non-contact capacitive EPIC electrodes in a headset system. The method involves incorporating only a single pair (two) of non-contact capacitive electrodes, positioned at targeted site of the scalp. The second important aspect is the consideration of the headset systems for maintaining stable position and contact at the interface between headset-based non-contact EPIC electrodes system and the targeted sites of scalp skin. The critical aspect is the optimization evaluation of contact pressure at the interface between headset-based non-contact EPIC electrode and scalp to minimising movement of the electrode with respect to the skin, and this will directly affect the optimal quality of the recording EEG signals. Thus, the classification performance of the recorded EEG signals can be optimised with maximum of subject comfort

An electro-mechanical contact formulation for DRY/WET electrode-scalp interfaces in an EEG headset

The process of generating an initial prototype for a new dry electrode wearable EEG headset system design can be time and resource intensive. The ability to predict the mechanical and electrical characteristics of this recording device could lead to major cost savings in this process. Since the skin surface roughness has a deep impact on the decrease of brain electric contact conductance (or the increase of the contact impedance) when electrode with bristles contact scalp skin, the estimation of electric conductance across rough dry and wet boundaries is a challenging task in the designing optimization of the wearable EEG headset system. In this contribution, the contact mechanism to predict the electrical impedance of scalp skin pressed against the electrode is considered as the electrical connection by the mechanical contact. With this, we have extended the Pohrt and Popov model by including the effects of conductive gel. An experiment is developed and carried-out to validate the interfacial contact impedance model

Performance of dry electrode with bristle in recording EEG rhythms across brain state changes

In this paper we evaluate the physiological performance of a silver-silver chloride dry electrode with bristle (B-Electrode) in recording EEG data. For this purpose, we compare the performance of the bristle electrode in recording EEG data with the standard wet gold-plated cup electrode (G-Electrode) using two different brain state change tasks including resting condition with eyes-closed and performing mathematical task with eyes-open. Using a 2 channel recording device, eyes-closed command data were collected from each of 6 participants for a period of 20sec and the same procedure was applied for the mathematical calculation task. These data were used for statistical and classification analyse. Although, B-electrode has shown a slightly higher performance compared with G-electrode in both tasks, but analyse did not reveal any significant differences between both electrodes in all six subjects tested. © 2011 IEEE

Variable ventilation improves pulmonary function and reduces lung damage without increasing bacterial translocation in a rat model of experimental pneumonia

Variable ventilation has been shown to improve pulmonary function and reduce lung damage in different models of acute respiratory distress syndrome. Nevertheless, variable ventilation has not been tested during pneumonia. Theoretically, periodic increases in tidal volume (VT) and airway pressures might worsen the impairment of alveolar barrier function usually seen in pneumonia and could increase bacterial translocation into the bloodstream. We investigated the impact of variable ventilation on lung function and histologic damage, as well as markers of lung inflammation, epithelial and endothelial cell damage, and alveolar stress, and bacterial translocation in experimental pneumonia. Thirty-two Wistar rats were randomly assigned to receive intratracheal of Pseudomonas aeruginosa (PA) or saline (SAL) (n\u2009=\u200916/group). After 24-h, animals were anesthetized and ventilated for 2 h with either conventional volume-controlled (VCV) or variable volume-controlled ventilation (VV), with mean VT\u2009=\u20096 mL/kg, PEEP\u2009=\u20095cmH2O, and FiO2\u2009=\u20090.4. During VV, tidal volume varied randomly with a coefficient of variation of 30% and a Gaussian distribution. Additional animals assigned to receive either PA or SAL (n\u2009=\u20098/group) were not ventilated (NV) to serve as controls.Conclusiosion: this rat model of pneumonia, VV improved pulmonary function and reduced lung damage as compared to VCV, without increasing bacterial translocation

Duração do aleitamento materno, regime alimentar e fatores associados segundo condições de vida em Salvador, Bahia, Brasil Breastfeeding duration, infant feeding regimes, and factors related to living conditions in the city of Salvador, Bahia, Brazil

Este trabalho tem como objetivo conhecer a duração do aleitamento materno, regime alimentar e fatores associados segundo condições de vida em Salvador, Bahia, Brasil. Este estudo de prevalência envolve 811 crianças menores de 24 meses. Para analisar os dados utilizou-se análise de sobrevivência, qui-quadrado de Pearson e regressão logística. A duração mediana do aleitamento exclusivo, predominante e total foi de 30,6, 73 e 131,5 dias, respectivamente. Identificou-se que 83,3% das crianças tiveram interrupção precoce do aleitamento exclusivo ou predominante. As crianças de famílias com condições de vida consideradas baixas tinham 2,3 vezes mais chances (IC95%: 1,09-5,01) de consumirem alimentos complementares precocemente; essa chance se elevou para 2,5 (IC95%: 1,20-5,34) entre aquelas de famílias com condições de vida muito baixas. A interrupção precoce do aleitamento exclusivo ou predominante associou-se com a maternidade em idade precoce e as precárias condições de vida das crianças e suas famílias. Programas direcionados à promoção da prática adequada do aleitamento materno e adoção da alimentação saudável na infância devem considerar a relevância dos fatores sociais envolvidos no oferecimento precoce de alimentos complementares à criança.<br>This cross-sectional study aimed to identify breastfeeding duration, infant feeding regimes, and factors related to living conditions among 811 children under 24 months of age in Salvador, Bahia, Brazil. Data were statistically analyzed by survival analysis, Pearson's chi-square test, and multivariate logistic regression. Median duration of exclusive, predominant, and total breastfeeding was 30.6, 73.0, and 131.5 days, respectively. Exclusive or predominant breastfeeding was discontinued in 83.6% of the subjects. Children with poor living conditions were 2.3 times more likely (95%CI: 1.09-5.01) to receive early supplementary food, whereas the figure for the very poor increased to 2.5 (95%CI: 1.20-5.34). Early exclusive or predominant breastfeeding discontinuation was associated with early pregnancy and poor living conditions of the children and their families. Programs directed towards proper breastfeeding and healthy feeding practices in childhood should consider the social factors associated with early introduction of supplementary foods in this population

Estudo caso-controle sobre exposição precoce ao leite de vaca e ocorrência de Diabetes Mellitus tipo 1 em Campina Grande, Paraíba Case-control study on early exposure to cow's milk and the occurrence of Diabetes Mellitus type 1 in Campina Grande in the State of Paraíba

OBJETIVOS: estudar a relação entre exposição precoce ao leite de vaca e ocorrência de Diabetes Mellitus tipo 1 entre menores de 18 anos atendidos no Hospital Universitário Alcides Carneiro, em Campina Grande. MÉTODOS: estudo caso-controle. A amostra foi constituída por 128 indivíduos de ambos os sexos. Foram entrevistadas 64 mães de portadores de Diabetes Mellitus e 64 mães de controles. Análises univariadas e multivariadas foram utilizadas. RESULTADOS: 84,4% dos indivíduos diabéticos foram expostos ao leite de vaca antes dos quatro meses de idade, enquanto que no grupo controle este percentual foi de 64,1%. A análise univariada identificou uma associação estatisticamente significante entre exposição precoce ao leite de vaca e Diabetes (p = 0,01). Na análise multivariada, essa associação permaneceu e a razão chances estimada foi de 4,09 (IC95%: 1,19 - 14,04; p = 0,01). CONCLUSÕES: os resultados indicam uma forte associação entre exposição precoce ao leite de vaca e ocorrência de Diabetes Mellitus tipo1 na população estudada. Assim, crianças expostas precocemente ao leite de vaca apresentam uma chance maior de adquirir a doença quando comparadas àquelas que receberam aleitamento materno exclusivo até pelo menos quatro meses após o nascimento.<br>OBJECTIVES: to study the relationship between early exposure to cow's milk and Diabetes Mellitus, type 1 among children under 18 years old seen at the Hospital Universitário Alcides Carneiro, in Campina Grande. METHODS: case-control study. Sample of 128 individuals of both sexes. Sixty-four mothers with Diabetes Mellitus type 1 and 64 mothers of a control group. Univariate and multivariate analysis was accomplished through logistic and conditional regression. RESULTS: 84,4% of diabetic individuals were exposed to cow mild before four months of age while in the control group this percentage was 64,1%. Univariate analysis determined a significant statistic association between early exposure to cow's milk and Diabetes (p = 0,01). In multivariate analysis this association remained and estimated odds ratio was of 4,09 (95% CI: 14,04; p = 0,01). CONCLUSIONS: results indicate a strong association between children with early exposure to cow's milk and Diabetes Mellitus type 1 events in the population studied. Therefore, children with early exposure to cow's milk have a higher chance of acquiring the disease when compared with those who were exclusively breastfed until at least until four months old