Design and evaluation of multi-band RF energy harvesting circuits and antennas for WSNs

Radio frequency (RF) energy harvesting is an emerging technology that will enable to drive the next generation of wireless sensor networks (WSNs) without the need of using batteries. In this paper, we present RF energy harvesting circuits specifically developed for GSM bands (900/1800) and a wearable dual-band antenna suitable for possible implementation within clothes for body worn applications. Besides, we address the development and experimental characterization of three different prototypes of a five-stage Dickson voltage multiplier (with match impedance circuit) responsible for harvesting the RF energy. Different printed circuit board (PCB) fabrication techniques to produce the prototypes result in different values of conversion efficiency. Therefore, we conclude that if the PCB fabrication is achieved by means of a rigorous control in the photo-positive method and chemical bath procedure applied to the PCB it allows for attaining better values for the conversion efficiency. All three prototypes (1, 2 and 3) can power supply the IRIS sensor node for RF received powers of -4 dBm, -6 dBm and -5 dBm, and conversion efficiencies of 20, 32 and 26%, respectively. © 2014 IEEE.

Serological and infection statuses of dogs from a visceral leishmaniasis-endemic area

OBJECTIVE This study investigated the serological status of dogs living in a visceral leishmaniasis-endemic area and its correlation with the parasitological condition of the animals.METHODS Canine humoral response was evaluated using the sera of 134 dogs by enzyme-linked immunosorbent assay and immunohistochemistry to detect parasites in the skin, lymph node, and spleen of the animals. The specific antibodies investigated were IgG, IgG1, IgG2, and IgE.RESULTS According to the parasitological, laboratory, and clinical findings, the dogs were placed into one of four groups: asymptomatic with (AP+, n = 21) or without (AP-, n = 36) Leishmania tissue parasitism and symptomatic with (SP+, n = 52) or without (SP-, n = 25) parasitism. Higher IgG and IgE levels were positively correlated with the infection condition and parasite load, but not with the clinical status. In all groups, total IgG was the predominant antibody, which occurred at the expense of IgG2 instead of IgG1. Most of the infected dogs tested positive for IgG (SP+, 98.1%; AP+, 95.2%), whereas this was not observed with IgE (SP+, 80.8%; AP+, 71.2%). The most relevant finding was the high positivity of the uninfected dogs for Leishmania-specific IgG (SP-, 60.0%; AP-, 44.4%), IgE (SP-, 44.0%; AP-, 27.8%), IgG1 (SP-, 28.0%; AP-, 22.2%), and IgG2 antibodies (SP-, 56.0%; AP-, 41.7%).CONCLUSIONS The serological status of dogs, as determined by any class or subclass of antibodies, did not accurately distinguish dogs infected with L. (L.) infantum chagasifrom uninfected animals. The inaccuracy of the serological result may impair not only the diagnosis, but also epidemiological investigations and strategies for visceral leishmaniasis control. This complex serological scenario occurring in a visceral leishmaniasis-endemic area highlights the challenges associated with canine diagnosis and points out the difficulties experienced by veterinary clinicians and coordinators of control programs.

Integrating the theme approach with aspectual scenarios

Dissertação de Mestrado em Engenharia Informática

Complex variable positive definite functions

In this paper we develop an appropriate theory of positive definite functions on the complex plane from first principles and show some consequences of positive definiteness for meromorphic functions.

Positive radial solutions of the Dirichlet problem for the Minkowski-Curvature equation in a ball

We study the existence and multiplicity of positive radial solutions of the Dirichlet problem for the Minkowski-curvature equation { -div(del upsilon/root 1-vertical bar del upsilon vertical bar(2)) in B-R, upsilon=0 on partial derivative B-R,B- where B-R is a ball in R-N (N >= 2). According to the behaviour off = f (r, s) near s = 0, we prove the existence of either one, two or three positive solutions. All results are obtained by reduction to an equivalent non-singular one-dimensional problem, to which variational methods can be applied in a standard way.

Ajustes posturais antecipatórios no alcance em crianças com hemiparésia espástica

Objectivos: Verificar o comportamento dos Ajustes Posturais Antecipatórios no alcance, em três crianças com hemiparésia espástica, face à aplicação de uma intervenção em Fisioterapia baseada numa abordagem segundo o conceito de Bobath. Pretendeu-se também perceber as modificações ao nível das actividades e participação, bem como ao nível da capacidade de modificação das componentes neuromotoras. Metodologia: A avaliação foi realizada antes e três meses após a intervenção através da electromiografia de superfície, máquina fotográfica Canon EOS, Classificação Internacional de Funcionalidade para Crianças e Jovens (CIF-CJ) e Sistema de Classificação da Função Motora Global (GMFCS). Resultados: Verificou-se melhorias nos Ajustes Posturais Antecipatórios no alcance com os dois membros superiores, nomeadamente no tempo de activação e na duração da actividade muscular, bem como alterações positivas nas componentes neuromotoras, como na sequência de movimento de sentado para de pé, e de pé para sentado, e marcha mais especificamente na fase pendular com o membro inferior predominantemente comprometido. Também se verificou após a intervenção uma maior funcionalidade nas três crianças, verificando-se alterações positivas nos qualificadores nas actividades e participação. Conclusão: A intervenção com base no conceito de Bobath induziu mudanças positivas quanto à funcionalidade das crianças, reflectindo-se nos Ajustes Posturais Antecipatórios e na reorganização de componentes de movimento.

Evaluation of the potential of translocated common cockle for ecological risk assessment studies: bioaccumulation and biomarkers test

Thesis submitted to the Faculdade de Ciências e Tecnologia to obtain the Master’s degree in Environmental Engineering, profile in Ecological Engineering

Estratégias de resolução de comportamentos de oposição e desafio

Relatório da Prática Profissional Supervisionada Mestrado em Educação Pré-Escolar

O trabalho da equipa como promotora da cooperação nas crianças

Relatório da Prática Profissional Supervisionada Mestrado em Educação Pré-Escolar

Exposição profissional a chumbo : utilização da protoporfirina-zinco (PPZ) na vigilância de saúde de trabalhadores ex

Resumo Uma estratégia de avaliação e prevenção de riscos na exposição a agentes químicos deve ter sempre em conta que a vigilância do ambiente de trabalho e a da saúde dos trabalhadores são aspectos complementares de uma mesma realidade – os riscos resultantes da interacção entre um agente químico e os trabalhadores a ele expostos. Se à Vigilância Ambiental compete apreciar o risco, pela caracterização do agente no ambiente de trabalho, a Vigilância Biológica pronuncia-se sobre a interacção entre o tóxico e o organismo, avaliando a resposta à agressão química e a evolução das reacções de adaptação ou de desajuste face à absorção do tóxico. Os Indicadores Biológicos, deste modo, assumem um estatuto de instrumento privilegiado na vigilância da saúde dos trabalhadores expostos, na medida em que medem a quantidade de tóxico que efectivamente penetrou e foi absorvido, ou o resultado (efeito) determinado por essa mesma dose. O presente estudo procura contribuir para a definição de um quadro metodológico de utilização dos Indicadores Biológicos na avaliação/gestão da exposição profissional ao chumbo, designadamente apreciando a variação da protoporfirina-zinco (PPZ), indicador até ao presente ainda não utilizado em Portugal. O chumbo é um metal de ocorrência natural, cujos níveis nos diversos ecossistemas resultam, principalmente, das actividades antropogénicas de natureza doméstica e industrial. A sua capacidade poluente é assinalável, representando uma fonte de exposição permanente para o homem, demonstrável pela sua constante presença no organismo apesar de não desempenhar qualquer tipo de função fisiológica. São actualmente inúmeras as suas aplicações, tornando a exposição profissional ao chumbo uma realidade vasta: indústrias de acumuladores eléctricos, de vidros, de plásticos e de munições, construção civil, manutenção e reparação automóvel e de navios, fabrico de tintas, indústrias electrónicas, fundições e actividades de soldadura são, entre outras, situações onde é uma realidade a ter em conta. A penetração dos compostos inorgânicos de chumbo no organismo efectua-se principalmente por via respiratória, não sendo, no entanto, desprezável, a sua penetração por via digestiva. As partículas absorvidas são transportadas pelo sangue principalmente ligadas aos eritrocitos (95%), distribuem-se pelos tecidos moles e depositam-se essencialmente no tecido ósseo, onde representam mais de 90% da carga corporal do total absorvido e tendo aí um elevado tempo de semi-vida (mais de 20 anos). Não é metabolizado no organismo e a sua eliminação efectua-se essencialmente por via renal,sendo igualmente excretado, em menor escala, através das fezes, do suor, da saliva, das faneras e do leite materno. O conhecimento científico evidencia que concentrações sanguíneas de chumbo entre 20 e 50 mg/dL são susceptíveis de determinar efeitos adversos no homem, podendo ser afectados o sistema hematopoiético, o sistema nervoso, o sistema cardiovascular, o sistema reprodutor e o sistema imunitário. Contudo, ainda muito há a clarificar no âmbito da toxicidade do chumbo. Os níveis de exposição a que correspondem as alterações nos diversos órgãos e sistemas continuam a ser motivo de alguma controvérsia. As características carcinogénicas e mutagénicas do chumbo são, ainda, um campo de vasta exigência de investigação. A intoxicação por chumbo e seus sais (Saturnismo) de origem ocupacional é reconhecida em Portugal como doença profissional (grupo 1 - Doenças Provocadas por Agentes Químicos, da Lista das Doenças Profissionais). É uma intoxicação do tipo crónico, fruto da absorção contínua de doses relativamente pequenas durante longo período, evidenciando-se no seu início por sinais e sintomas vagos e difusos de grande inespecificidade, que podem incluir, nomeadamente, perda de apetite, sabor metálico na boca, palidez, mal-estar e fadiga, cefaleias, mialgias e artralgias, irritabilidade, tremores finos, obstipação, cólicas abdominais, insónias, déficit da memória de curto prazo e da capacidade de concentração. Um importante conjunto de indicadores biológicos pode ser utilizado na vigilância periódica da saúde de trabalhadores nestas condições de exposição. Tais indicadores (de dose ou de efeito), encerram diferentes significados e comportam distintas exigências, competindo ao Médico do Trabalho, no âmbito dos programas de prevenção dos efeitos adversos relacionados com a exposição profissional a chumbo, seleccionar a sua utilização e interpretar a sua informação, de modo a avaliar a interacção do tóxico com o organismo numa fase de reversibilidade. O presente estudo envolveu 180 trabalhadores dos quais 110 apresentavam plumbémias (Pb-S) iguais ou superiores a 40 mg/dL. Além da Pb-S, a todos foi doseada a protoporfirina-zinco (PPZ) e efectuado o Hemograma e a cerca de 25% foi determinada a concentração do ácido d-aminolevulínico urinário (ALA-U). Os doseamentos da PPZ efectuados em amostra de sangue capilar através de um hematofluorímetro portátil revelaram-se de total fiabilidade, dando significado a uma técnica de fácil execução e baixo custo. A avaliação do tipo de colheita urinária para doseamento do ALA-U concluiu pela necessidade de recurso a urinas de 24 horas.Os resultados do estudo evidenciaram uma elevada associação entre a PPZ e a Pb-S, com uma maior magnitude e de início mais precoce do que o que registado na associação da Pb-S com o ALA-U. Revelaram, ainda, fracos níveis de associação da hemoglobina (e outros parâmetros hematológicos) com a Pb-S. E demonstraram para um cut-off de 100 mg/ dL de PPZ, taxa de falsos negativos e falsos positivos, para plumbémias a partir de 70 mg/dL, inferiores a 20%. Assim, concluiu-se que, nos protocolos de vigilância de saúde de trabalhadores expostos a chumbo, o doseamento da PPZ por hematofluorímetro, em sangue de colheita capilar, é adequado, fiável e de realização preferencial em relação ao do ALA-U. Concluiu-se, também, que a realização do hemograma apenas se justifica em situações individuais que clinicamente o tornem aconselhável. E que estes protocolos devem incluir a realização da Pb-S e da PPZ, podendo, em situações de controlo rigoroso (ambiental, biológico e clínico), basear-se apenas na determinação da PPZ reservando os outros indicadores para aprofundar a investigação médica nos casos de taxas elevadas desta ou de situações limitantes. ■ Résumée Une stratégie d’évaluation et de prévention des risques d’exposition aux agents chimiques doit toujours tenir en considération que la vigilance du lieu de travail et de la santé des travailleurs sont des aspects complémentaires d’une même réalité – les risques résultant d’une interaction entre l’agent chimique et les travailleurs exposés. Si c’est à la Vigilance Ambiantale de juger le risque, par la caractérisation de l’agent dans le lieu de travail, la Vigilance Biologique, elle, se prononce sur l’interaction entre le toxique et l’organisme, évaluant la réponse à l’agression chimique et l’évolution des réactions d’adaptation ou de rupture face à l’absorption du toxique. Les Indicateurs Biologiques assument ainsi un statut d’instrument privilégié de vigilance de la santé des travailleurs exposés, dans la mesure où ils déterminent la quantité de toxique qui a effectivement été pénétré et absorbé, ou le résultat (effet) déterminé par cette dose. Cette étude-ci cherche à contribuer à la définition d’un cadre méthodologique d’utilisation des Indicateurs Biologiques dans l’évaluation/ gestion de l’exposition professionnelle au plomb inorganique, évaluant spécialement le comportement de la protoporphirine-zinc (PPZ), indicateur pas encore utilisé au Portugal.Le plomb est un métal d’occurrence naturelle dont les niveaux dans les différents écosystèmes en résultent, principalement, des activités anthropogéniques de nature domestique et industrielle. Sa capacité polluante peut être signalée, représentant une source d’exposition permanente pour l’homme, celle-ci démontrable par sa présence continue dans l’organisme, même si elle n’y accomplit aucune fonction physiologique. Actuellement ses applications sont innombrables, faisant de l’exposition professionnelle au plomb une réalité de grande ampleur : industries d’accumulateurs électriques, de verre, de plastique et de munitions, bâtiments, manutention et réparation automobile et navale, fabrication d’encres, industries électroniques, fontes et activités de soudure sont, entre autres, des situations réelles a en tenir compte. La pénétration du plomb inorganique dans l’organisme se fait principalement par voie respiratoire, pouvant se faire également par voie digestive. Les particules absorbées sont transportées par le sang, surtout liées aux érythrocytes (95%), se repartent à travers les tissus mous et se déposent essentiellement dans le tissu osseux, où elles représentent plus de 90% de la charge corporelle de ce qui a été absorbé et ont un temps de demi-vie élevé (plus de 20 ans). Le plomb n’est pas métabolisé dans l’organisme et son élimination se fait essentiellement par voie rénale, pouvant tout de même, à une moindre échelle, être excrété dans les fèces, de la sueur, de la salive, des ongles, des cheveux et du lait maternel. La connaissance scientifique met en évidence que des concentrations sanguines de plomb entre 20 et 50 mg/dL sont susceptibles de déterminer des effets adverses dans l’homme, pouvant les systèmes hématopoïétique, nerveux, cardiovasculaire, reproducteur et immunitaire en être affectés. Cependant, il en reste beaucoup à éclaircir dans le domaine de la toxicité du plomb. Les niveaux d’exposition auxquels correspondent les modifications des divers organes et systèmes, demeurent toujours sujet de quelque controverse. Les caractéristiques carcinogèniques et mutagèniques du plomb restent toujours un champ d’investigation d’une grande exigence. L’intoxication par le plomb et ses sels (Saturnisme) d’origine occupationnelle est reconnue, au Portugal, comme une maladie professionnelle (groupe 1- Maladies Provoquées par des Agents Chimiques, de la Liste des Maladies Professionnelles). C’est une intoxication du tipe chronique, due à l’absorption continue de doses relativement petites pendant une longue période, mise en évidence à travers des signes et des symptômes vagues et diffus sans grande spécificité, lesquels peuvent inclure, particulièrement, le manque d’appétit, goût métallique dans la bouche, pâleur, malaise et fatigue, céphalées, myalgies et arthralgies, irritabilité, tremblements fins, constipation, coliques abdominales, insomnies, déficit de la mémoire à court terme et de la capacité de concentration.Un ensemble important d’indicateurs biologiques peut être employé dans la vigilance périodique de la santé des travailleurs dans ces conditions d’exposition. Ces indicateurs (de dose ou d’effet) renferment différentes significations et comportent diverses exigences, devant le Médecin de Travail, dans le domaine des programmes de prévention des effets adverses qui sont en relation avec l’exposition professionnelle au plomb, sélectionner son utilisation et interpréter son information de façon à évaluer l’interaction de l’élément toxique avec l’organisme à un stade de réversibilité. L’étude ci-présent engloba 180 travailleurs desquels 110 présentaient des plombémies (Pb-S) égales ou supérieures à 40 mg/dL. À part la Pb-S, la protoporphyrine-zinc (PPZ) leur a été prise en dosage et un Hémogramme fut effectué et fut déterminé l’acide d- aminolévulinique urinaire (ALA-U) sur environ 25% des travailleurs. Le dosage de la PPZ efectué en échantillon de sang capillaire par un fluorimètre portable, s’est accomplit d’une fiabilité total, donnant du sgnificat à une téchnique de facile execution et bas prix. L’évaluation de la prise urinaire par dosage du ALA-U conclut au besoin d’un recours aux urines de 24 heures Les résultats de l’étude ont mis en évidence une association élevée entre la PPZ et la Pb- S, avec une intensité majeure et de début plus précoce par rapport à celui qui fut registré lors de l’association de la Pb-S avec la ALA-U. Ces résultats ont également montré de faibles niveaux d’association entre l’hémoglobine (et autres paramètres hématologiques) et la Pb-S. Ils ont démontré aussi, une valeur de cut-off de 100 mg/dL de PPZ, des taux de faux négatifs et faux positifs, pour des plombémies de 70 mg/dL, inférieurs à 20%. On peut donc conclure que dans les protocoles de vigilance de la santé des travailleurs exposés au plomb, le dosage de la PPZ par fluorimetrie dans le sang capillaire est adéquat, fiable et de réalisation préférentielle par rapport à celui du ALA-U. On peut également conclure que la réalisation de l’hémogramme ne se justifie que dans les cas individuels où, cliniquement, celui-ci est conseillé. De plus, ces protocoles doivent inclure la réalisation de la Pb-S et de la PPZ, pouvant, en cas de contrôle rigoureux (ambiantal, biologique et clinique), s’appuyer que dans la détermination de la PPZ réservant les autres indicateurs pour approfondir l’investigation médicale dans les cas où les taux de celle-ci sont élevés ou dans les cas de situations limitantes. ■ Summary Any strategy to evaluate and prevent the risks of chemical agents exposure must always regard the work environment and workers health as complementary aspects of one reality - the resulting risks from the interaction between the chemical agent and the exposed workers. It is the responsibility of Environmental Monitoring to evaluate the risks of exposure by the characterization of the chemical agent in the work environment. Biological Monitoring, on the other hand, pronounces itself over the toxin and body interaction, evaluating human response to the chemical aggression and the body adaptations to the toxic absorption. Biological Exposure Indices (BEI) assume, therefore, a privileged status among exposed workers' health monitoring instruments, as they measure the actual penetrated and absorbed toxic quantity and the effect it produces. This research study aims to contribute to the definition of a methodological strategy on the utilization of BEI’s in evaluating inorganic lead's occupational exposure, more specifically appreciating the zinc protoporphyrin (ZPP) variation, an index that has never been taken under consideration in Portugal until now. Lead is a natural metal whose ecosystem’s levels are mainly due to domestic and industrial anthropogenic activities. Its pollutant capacity is notable, representing a permanent exposure risk shown by its constant presence in the human body, although it has no physiologic function. Nowadays, lead's applications are countless, turning its professional exposure a huge reality: storage batteries industries, glass industries, plasterers and munitions industries, building construction, ships and motor car maintenance and repairing, ink manufacture, electronics industries, foundries and other soldering activities are, among so many other, realities to attend to. Respiration is the main cause of human body's inorganic lead absorption, although digestive pathway must not to be ignored. The absorbed particles are transported by blood, essentially bounded to erythrocytes (95%). It is distributed by soft tissues and settled mainly on bone tissues, where it represents approximately 90% of the total body charge and has a high half-life time (more than 20 years). It is not metabolized by the organism, its elimination being effectuated by renal activity and, in smaller scale, through lees, sweat, saliva, nails, hair and maternal milk.Scientific knowledge shows that concentrations of lead in blood between 20 e 50 mg/dL are susceptible to determine adverse effects in man and able to affect the hematopoietic system, the nervous system, the cardiovascular system, the reproductive system and the immunological system. Nevertheless, there's still much to be learned and clarified about lead's toxicity. The correlation between exposure levels and human's systems and organs alteration levels continues to be a centre of controversies. Still, lead's carcinogenic and mutagenic characteristics continue to be a high demanding research field. Intoxication by lead and its compounds (saturnism), from occupational origin, is recognized in Portugal as an occupational disease, included in Group 1 - Chemical Agents Caused Diseases, on the Occupational Diseases List. It is a chronic intoxication caused by a continuous absorption of small doses, throughout a long period of time. Its signs and symptoms are diffuse and imprecise, of great unspecificity, such as loss of appetite, metallic flavor in the mouth, paleness, ailment and fatigue, headaches, myalgia and arthralgia, irritability, thin tremors, constipation, abdominal pain, insomnias, short memory loses and inability to concentrate. A considered number of BEI’s can be used in Periodic Health Monitoring of workers in such exposure conditions. Such BEI (dose indices or effect indices) provide different meanings and imply different procedures, being Occupational Doctors responsibility, in the context of lead related adverse effects preventive programmes, to select and interpret its information, in order to evaluate the interaction between toxic and organism in a reversible phase of the toxic action. The present research study involved 180 workers, 110 of which presented blood lead levels (PbB) above or equal to 40 mg/dL. Besides PbB, all workers has been evaluated for zinc protoporphyrin levels (PPZ) and submitted to a haemogram. About 25% of the workers were selected for d-aminolevulinic urinary acid (ALA-U) determination. The evaluation of PPZ, by a portable hematofluorometer using capillary blood samples, turned out to be an easy procedure with low costs and total warrantability. As in regard for ALA- U procedure, it was concluded the necessity of 24 hours urine samples. This research results underlined a strong connection between ZPP and PbB, which was found to to be stringer and to begin earlier than it was registered for PbB and ALA-U association. The same study also revealed a low association level between PbB and hemoglobin or other hematological indices. It was also verified less than 20% of false negatives and false positives cases when admitted a ZPP 100 mg/dL cut off value for PbB³ 70 mg/dL. As in result it was concluded that in Health Monit

Das perceções das crianças sobre alguns animais mal-afamados à sua (re) construção em contexto de sala de aula

Relatório de Estágio apresentado à Escola Superior de Educação de Lisboa para obtenção do grau de mestre em Ensino do 1.º e 2.º Ciclo do Ensino Básico

Study on the changes of soil chemical characteristics as result of prescribed fire

Every year, particularly during the summer period, the Portuguese forests are devastated by forest fire that destroys their ecosystems. So in order to prevent these forest fires, public and private authorities frequently use methods for the reduction of combustible mass as the prescribed fire and the mechanical vegetation pruning. All of these methods of prevention of forest fires alter the vegetation layer and/or soil [1-2]. This work aimed the study of the variation of some chemical characteristics of soil that suffered prescribed fire. The studied an area was located in the Serra of Cabreira (Figure 1) with 54.6 ha. Twenty sampling points were randomly selected and samples were collected with a shovel before, just after the prescribed fire, and 125 and 196 days after that event. The parameters that were studied were: pH, soil moisture, organic matter and iron, magnesium and potassium total concentration. All the analysis followed International Standard Methodologies. This work allowed to conclude that: a) after the prescribed fire; i) the pH remained practically equal to the the initial value; ii) occurred a slight increase of the average of the organic matter contents and iron total contents; b) at the end of the sampling period compared to the initial values; i) the pH didn´t change significantly; ii) the average of the contents of organic matter decreased; and iii) the average of the total contents of Fe, Mg and K increased.

Relationship between the prevalence of antibodies to arbovirus and hepatitis B virus in the Vale do Ribeira region, Brazil

280 students, between 6 and 14 years old, residents in the Iguape county, southern coast of the State of São Paulo, were studied in order to identify the existence of a possible association between the prevalence of specific antibodies to the hepatitis B virus and the exposure to haematophagous mosquitoes, evaluated indirectly through the prevalence of antibodies to 17 arboviruses isolated in Brazil. The children were from 4 areas with different topographical characteristics: 89 of the children were from the urban zone of the town of Iguape, 89 were from the periurban zone, 30 were from the rural area with extensive banana plantations, and 72 were from the jungle zone. Previous studies had shown significantly higher prevalence of antibodies to different arboviruses in the cultivated zone and the jungle zone, when compared to the urban and periurban zones of Iguape. The detection of antibodies to the HBV surface antigen (HBs Ag) was done through the radioimmunoassay (Ausab, Abbott Laboratory). The cases considered positive were confirmed through the presence of anti-core HBV antibodies (anti-HBc-EIA Roche). A significantly higher prevalence of anti-HBV antibodies was observed in children from the jungle zone (26/72 = 36,1% ) when compared to those from the urban zone (5/89 = 5,6%), peri-urban (6/89 = 6,7%) or from the cultivated zone (0/30 = 0%). The result suggest the existence of a common factor in the dissemination of the arboviruses and the hepatitis B virus, supporting the hypothesis that mosquitoes may play an important role in the HBV transmission in tropical forested region.

Serological studies on shistosomiasis mansoni in the Northeast Brasil

Sera from the patients (N = 10) with schistosomiasis mansoni of the hospital of Federal University of Pernambuco, the Schistosoma mansoni egg-positive (N = 51) and -negative (N = 452) inhabitants in Cabo City area, out-patients (N = 37) of the IMIP hospital and Japanese immigrants (N = 127) in Petrolina City area of northeast Brazil as well as Japanese healthy subjects (N = 30) were examined by serological tests including an enzyme-linked immunosorbent assay with antigens prepared from eggs (ELISA-egg) and adult worms (ELISA-adult). The ELISA with egg or adult antigen correctly identified 100% of the uninfected individuals lived in non-endemic area of schistosomiasis. Moreover, when examined cross-reactivity of our ELISA with sera isolated from 78 subjects infected with various intestinal parasitic infections, only one of these sera reacted with the egg and adult antigens. On the examination of 51 sera from the egg-positive subjects, the ELISA-egg revealed the highest sensitivity (98.0%), whereas a large number of false negative reactions of ELISA-adult, Ouchterlony method using adult antigen, circumoval precipitation and immediate intradermal skin test were observed. A low sensitivity of these serologic tests except for ELISA-egg appears to be primarily due to their inability to detect antibody in the sera from egg-positive infantiles. There was no positive correlation between the absorbance values of these two types of ELISA among the sera isolated from ELISA-positive subjects. Rather, by the reactivity of these sera to egg or adult antigen, they could be divided into two subgroups; one reacted more positively with egg antigen and the other with adult antigen. Moreover, it was confirmed that the sera from young subjects (under 20 years old) appear to be highly reactive to the egg antigen than did aged ones. These data suggest that the ELISA with egg antigen, but not with the adult antigen, appears to be useful for the serological survey of schistosomiasis mansoni in the endemic area of northeast Brazil.

Predictors of infant positive, negative and self-direct coping during face to face still-face in a Portuguese preterm sample

Past studies found three types of infant coping behaviour during Face-to-Face Still-Face paradigm (FFSF): a Positive Other-Directed Coping; a Negative Other-Directed Coping and a Self-Directed Coping. In the present study, we investigated whether those types of coping styles are predicted by: infants’ physiological responses; maternal representations of their infant’s temperament; maternal interactive behaviour in free play; and infant birth and medical status. The sample consisted of 46, healthy, prematurely born infants and their mothers. At one month, infant heart rate was collected in basal. At three months old (corrected age), infant heart-rate was registered during FFSF episodes. Mothers described their infants’ temperament using a validated Portuguese temperament scale, at infants three months of corrected age. As well, maternal interactive behaviour was evaluated during a free play situation using CARE-Index. Our findings indicate that positive coping behaviours were correlated with gestational birth weight, heart rate (HR), gestational age, and maternal sensitivity in free play. Gestational age and maternal sensitivity predicted Positive Other-Direct Coping behaviours. Moreover, Positive Other-Direct coping was negatively correlated with HR during Still-Face Episode. Self-directed behaviours were correlated with HR during Still-Face Episode and Recover Episode and with maternal controlling/intrusive behaviour. However, only maternal behaviour predicted Self-direct coping. Early social responses seem to be affected by infants’ birth status and by maternal interactive behaviour. Therefore, internal and external factors together contribute to infant ability to cope and to re-engage after stressful social events.