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Livestock excreta is one of the major nutrient sources in natural grasslands. Understanding how livestock diet and season affects the decomposition dynamics is critical to nutrient cycling models. We hypothesised that livestock diet and season of the year affect dung decomposition. This study evaluated the decomposition and release of N, P, K, Ca, Mg, and Na from faeces of cattle collected in dry and wet seasons. Treatments were signalgrass (Brachiaria decumbens Stapf) in monoculture or mixed with sabia (Mimosa caesalpiniifolia Benth.) or gliricidia (Gliricidia sepium (Jacq.) Kunth ex Walp.). Excreta samples were incubated in nylon bags for 0, 2, 4, 8, 16, 32, 64, 128 and 256 d. The single negative exponential mathematical model was adequate (P < 0.0001) to explain the decomposition. The relative rate of dung decomposition (k) was greater for samples that originated from cattle grazed on signalgrass (k = 0.00284 g g−1 d−1), followed by sabia (k = 0.00233 g g−1 d−1), and gliricidia (k = 0.00200 g g−1 d−1) ...

This paper presents the design of a low-pass microwave filter based on the EBG (electromagnetic bandgap) concept. The structure is composed of a microstrip line in one of the layers and two different periodic superimposed EBG structures in the ground plane. The first structure defines the characteristics of the filter in the pass-band whereas the second periodic structure is used to reduce the second harmonic spurious response. The filter exhibits a fiat pass-band response and a cut-off rate better than 380 dB/octave.

OBJETIVO: Descrever os achados clínico-laboratoriais da endocardite infecciosa (EI) em 28 crianças, em Vitória/ES. MÉTODO: Estudo retrospectivo dos prontuários de 28 crianças, com idade abaixo de 18 anos e diagnóstico de endocardite infecciosa, internadas no serviço de infectologia do Hospital Infantil Nossa Senhora da Glória, em Vitória - Espírito Santo, no período de janeiro de 1993 a dezembro de 2001. Os critérios para diagnóstico de endocardite infecciosa foram os do Duke Endocarditis Service (Duke University, Durham, North Carolina - USA): critérios maiores (hemoculturas e ecocardiograma positivos) e critérios menores (febre, doença cardíaca prévia, sopro cardíaco recente, fenômenos vasculares e imunológicos). Através de protocolo específico, preenchido pelos médicos-residentes e acadêmicos do serviço de infectologia, e revisados pelos médicos da equipe, foram anotadas as idades, sexo, achados clínicos e laboratoriais, e os resultados da ecocardiografia transtorácica das 28 crianças que preenchiam os critérios clínicos e laboratoriais. Em todos os casos, as hemoculturas foram realizadas com coleta do sangue (três amostras), sob condições assépticas e com inoculação em meios aeróbicos e anaeróbicos, incubados a uma temperatura de 37ºC e testados com sistema automatizado Vitec System® (Biolab). RESULTADOS: Das 28 crianças, 16 eram do sexo masculino, com idade entre 3 e 180 meses (média 70,6±59,2 m), e a maioria (68%) era procedente da região metropolitana de Vitória. Metade apresentava cardiopatia prévia. Os achados clínicos mais freqüentes que levaram à suspeita de EI foram: febre prolongada (100%), sopro cardíaco (67,9%), dispnéia (57,1%), hepatomegalia (57,1%), fenômenos vasculares (32,2%), esplenomegalia (28,6%) e nódulos de Osler (7,1%). Foram colhidas hemoculturas dos 28 casos, sendo 16 (57,1%) positivas. O S. aureus adquirido na comunidade foi o germe mais freqüentemente isolado (9/16-56,6%). Houve persistência da febre, apesar do tratamento, duração da febre de 2,5 a 30 dias, mediana de 18,0 dias. O valor médio de leucócitos à internação foi de 11.657±7.085mm³. O ecocardiograma transtorácico, realizado em todos os pacientes, evidenciou vegetações, principalmente nas válvulas tricúspide (25,0%), mitral (25,0%) e na borda de CIV (28,6%). Treze (46,4%) crianças apresentaram sepse concomitante, e três (10,7%) infecção hospitalar. Houve um óbito (3,6%). CONCLUSÕES: A endocardite infecciosa em nosso meio é freqüente em crianças abaixo de dois anos de idade e com uma cardiopatia congênita. O S. aureus de origem comunitária foi o microorganismo isolado mais freqüentemente, e em crianças sem lesão cardíaca prévia. Endocardite infecciosa aguda, endocardite bacteriana, Staphylococcus aureus, ecocardiografia transtorácica. OBJECTIVE: To describe clinical and laboratory data of infective endocarditis (IE) in 28 children from Vitória, state of Espírito Santo, Brazil. METHODS: We reviewed the medical records of 28 children aged 18 years and under admitted to the Infectious Diseases Unit of Nossa Senhora da Glória Children's Hospital with a diagnosis of IE from January 1993 to December 2001. The diagnosis of IE was based on the criteria established by the Duke Endocarditis Service (Duke University, Durham, North Carolina, USA): positive blood cultures and echocardiogram (primary criteria); and fever, history of heart disease, recent heart murmur, and vascular and immunological phenomena (secondary criteria). A specific protocol was filled out by interns and medical students and revised by physicians from the hospital medical team to obtain the following data: age, sex, clinical and laboratory findings, and results of transthoracic echocardiography. In all cases, three blood samples were collected under aseptic conditions and inoculated in aerobic and anaerobic environments. The samples were then incubated at 37º C and tested with the VITEC SYSTEM® automatized system (BIOLAB). RESULTS: Among 28 patients, 16 were boys. Age was between 3 and 180 months (mean 70.6 ± 59.2 months). Most children (68%) came from the metropolitan area of Vitória, and half presented a history of cardiopathy. The most frequent clinical findings which led to suspicion of IE were: prolonged fever in all cases, new or changing regurgitant murmur (67.9%) , dyspnea (57.1%), hepatomegaly (57.1%), vascular phenomena (32.2%), splenomegaly (28.6%), and Osler's nodes (7.1%). Blood cultures were positive in 16 patients (57.1%), and community-acquired S. aureus was the most frequently isolated pathogen (56.6%). Despite the treatment, fever persisted for 2.5 to 30 days (median = 18.0 days). Mean leukocyte count at admission was 11,657±7,085mm3. Transthoracic echocardiography showed endocardial lesion in all patients, evidencing vegetations in the tricuspid valve (25%), mitral valve (25%), and intraventricular communication border (28%). Thirteen (46.4%) children presented concomitant sepsis and three (10.7%) developed hospital-acquired infection. There was one death (3.6%). CONCLUSIONS: IE in our country is frequent among children younger than 2 years with congenital cardiopathy. Community-acquired S. aureus was the most frequently isolated microorganism in children with no previous cardiac lesion. Acute infective endocarditis, bacterial endocarditis, Staphylococcus aureus, transthoracic echocardiography.