BACKGROUND: Although chronic lung disease (CLD) is commonly seen in children with advanced HIV disease, it is poorly studied. OBJECTIVES: To report on the clinical manifestations and lung function tests in children with advanced HIV disease at a tertiary care centre, and determine clinical predictors of poor lung function. METHODS: We undertook a cross-sectional study of children with advanced HIV disease in whom CLD was suspected. We undertook clinical evaluation and lung function tests, accompanied by a retrospective chart review. RESULTS: In 56 children identified, the median age was 5 (interquartile range (IQR) 2 - 8) years with equal gender ratio. The majority (93%) had been previously treated for tuberculosis and/or pneumonia (71%). The most common CLD identified was lymphocytic interstitial pneumonitis (54%). The median nadir CD4 percentage was 13% (IQR 8.5 - 16%) and the median highest reported viral load was log5.8 (IQR log5.0 - log6.5). The median duration of antiretroviral therapy was 9.8 (IQR 1.1 - 19.5) months. Lung function tests were performed in 27 (48%) children. The median forced expiratory volume in 1 second (FEV1) was 60% (IQR 45.3 - 86.3%) predicted. Previous hospitalisation, respiratory rate, digital clubbing, chest hyperinflation and hyperpigmented skin lesions were associated with a decreased FEV1 in a univariate relationship. In a multiple linear regression analysis, hyperinflation, increased respiratory rate and hyperpigmented skin lesions were associated with poor lung function (percentage FEV1. CONCLUSION: We identified useful clinical signs predictive of poor lung function in HIV-infected children with CLD, especially in resource-limited settings.

Sugarcane is an important agricultural product of Brazil, with a total production of more than 500 million tons. Knowledge of the bacterial community associated with agricultural crops and the soil status is a decisive step towards understanding how microorganisms influence crop productivity. However, most studies aim to isolate endophytic or rhizosphere bacteria associated with the plant by culture-dependent approaches. Culture-independent approaches allow a more comprehensive view of entire bacterial communities in the environment. In the present study, we have used this approach to assess the bacterial community in the rhizosphere soil of sugarcane at different times and under different nitrogen fertilization conditions. At the high taxonomic level, few differences between samples were observed, with the phylum Proteobacteria (29.6%) predominating, followed by Acidobacteria (23.4%), Bacteroidetes (12.1%), Firmicutes (10.2%), and Actinobacteria (5.6%). The exception was the Verrucomicrobia phylum whose prevalence in N-fertilized soils was approximately 0.7% and increased to 5.2% in the non-fertilized soil, suggesting that this group may be an indicator of nitrogen availability in soils. However, at low taxonomic levels a higher diversity was found associated with plants receiving nitrogen fertilizer. Bacillus was the most predominant genus, accounting for 19.7% of all genera observed. Classically reported nitrogen-fixing and/or plant growth-promoting bacterial genera, such as Azospirillum, Rhizobium, Mesorhizobium, Bradyrhizobium, and Burkholderia were also found although at a lower prevalence.

In this work a particular system is investigated consisting of a pendulum whose point of support is vibrated along a horizontal guide by a two bar linkage driven from a DC motor, considered as a limited power source. This system is nonideal since the oscillatory motion of the pendulum influences the speed of the motor and vice-versa, reflecting in a more complicated dynamical process. This work comprises the investigation of the phenomena that appear when the frequency of the pendulum draws near a secondary resonance region, due to the existing nonlinear interactions in the system. Also in this domain due to the power limitation of the motor, the frequency of the pendulum can be captured at resonance modifying completely the final response of the system. This behavior is known as Sommerfeld effect and it will be studied here for a nonlinear system.

In this paper is Analyzed the local dynamical behavior of a slewing flexible structure considering nonlinear curvature. The dynamics of the original (nonlinear) governing equations of motion are reduced to the center manifold in the neighborhood of an equilibrium solution with the purpose of locally study the stability of the system. In this critical point, a Hopf bifurcation occurs. In this region, one can find values for the control parameter (structural damping coefficient) where the system is unstable and values where the system stability is assured (periodic motion). This local analysis of the system reduced to the center manifold assures the stable / unstable behavior of the original system around a known solution.

Com o objetivo de obter dados referentes ao crescimento e concentração e acúmulo de macronutrientes em função da idade da planta, foram coleta das amostras de folhas, galhos secos, ponta e base de galhos primários, e ponta, meio e base do tronco de plantas de seringueira clone Fx 3864 com 1,0 a 4,0 anos de idade em plantações situadas sobre Latossol Vermelho-Amarelo textura argilosa na área da BONAL S.A., localizada na região de Rio Branco, AC. Os resultados obtidos mostraram que: - O maior incremento no crescimento ocorreu a partir do terceiro ano. - As maiores concentrações de nutrientes, ocorreram nas folhas. - A extração de nutrientes pela seringueira, por hectare, no quarto ano, foi a seguinte: N - 24, 54 kg, P - 1,82 kg, Ca - 11,07 kg, Mg - 5,29 kg, S - 1,88 kg, - região do Amazonas. - A extração total de macronutrientes pelo sistema, em ordem decrescente: N K Ca Mg S P.

Primary objective of this work was to study the growth, and concentration and accumulation of macronutrierts on the Hevea brasiliensis plants, at various ages. Leaves, stems and branches of rubber tree clone Fx 3864 from one year up to years old were collected from a plantation located at the BONAL S.A. farm at Rio Branco, Brasil the soil under the forest was classified as a heavy texture Red-Yellow Latosol. Results obtained showed that: - Highest growth increment occured from the third year on. - The leaves had the highest nutrient concentration - During the fourth year, nutrient extraction per hectare was: N - 24.54 kg, P - 1.82 kg, K - 18.29 kg, Ca - 11.07 kg, Mg - 5-29 kg, S - 1,88 kg. - Total macronutrients were absorbed in the following decreasing order: N, K, Ca, Mg, S, P.

Com o objetivo de obter dados referentes a concentração e acúmulo de micronutrientes em função da idade da planta, foram coletadas amostras de folhas, galhos secos, ponta e base de galhos primários, e ponta, meio e base do tronco de plantas de seringueira clone Fx 3864 com 1 a 4 anos de idade situadas sobre Latossol Vermelho-Amarelo, textura argilosa na área da BONAL S.A. localizada na região de Rio Branco, AC Os resultados mostraram que: 1. As maiores concentrações de nutrientes ocor rem nas folhas com exceção do cobre e zinco; 2. A extração de nutrientes por hectare no quarto ano foi de: B-29,4 g, Cu-18,3 g, Fe - 140 g, Mn - 437,7 g e Zn - 52,2 g; 3. A extração total de nutrientes, em ordem decrescente foi: Fe Mn Zn B Cu.

Primary objective of this work was to study concentration and accumulation of the micronutrients on the rubber plants, at variuns ages. Leaves, stems and branches from one year up to four years old were collected from a plantation located at the BONAL S.A. farm at Rio Branco, Brazil. The soil under the forest was classified as a heavy texture Red-Yellow Latossol. The results showed: The leaves had the highest nutrient concentration, with the exception for copper and zinc. During the fourth year, nutrient extraction per hectare was: 29.4 g B; 18.3 g Cu; 140.4 g Fe; 436.7 g Mn and 52.2 Zn. Total micronutrients were absorbed in the following decreasing order: Fe > Mn > Zn > B > Cu.

Plantas de cubiu (Solanum topiro Humb. & Bonpl.), 'INPA-P6-PL2-BLII-Exp l', foram cultivadas, em casa de vegetação em quartzo moído, irrigadas com soluções nutritivas, conforme SARRUGE (1975), e submetidas aos seguintes tratamentos: completo, omissão de N, omissão de P, omissão de K, omissão de Ca, omissão de Mg e omissão de S, com o objetivo de: (a) obter sintomas de deficiência dos macronutrientes; (b) analisar o crescimento das plantas através da produção de matéria seca; (c) determinar a concentração dos macro e micronutrientes, exceto molibdênio e cloro, nas folhas, caules e raízes das plantas. Os sintomas visuais de deficiência foram identificados e descritos. As plantas foram coletadas e separadas em raiz, caule e folhas, e determinaram-se os teores de macro e micronutrientes, exceto molibdênio e cloro, neste material. Os resultados obtidos mostram: a) os sintomas visuais de deficiência de nitrogênio, potássio, cálcio e magnésio são bem definidos e de fácil caracterização, não ocorrendo o mesmo para os sintomas visuais de deficiência de fósforo e enxofre; b) os tratamentos que mais afetaram o desenvolvimento das plantas foram: omissão de N, omissão de P e omissão de K, seguidos por omissão de Ca e omissão de Mg. O desenvolvimento das plantas não foi afetado com o tratamento omissão de S; c) os níveis de deficiência e adequação obtidos nas folhas foram: N% = 2,02-2,53 P% = 0,12-0,20; K% = 0,84-3,44; Ca% = 0,22-2,64; Mg% = 0,07-0,48; S% = 0,10 0,25.

In order to obtain: a) a clear picture of the picture of the deficiency symptoms of N, P, K, Ca, Mg, and S; b) the effects of lack of the elements on the dry matter production, and; c) concentrations of the macro and micronutrients, excepted for Mo and CI, on the leaves, stems and roots; young cubiu plants (Solanum topiro Humb. & Bonpl.), 'INPA-P6-PL2-BLUU-Exp l', were cultivated in nutrient solutions, in which one of the following elements were omitted at once: N, P, K, Ca, Mg and S. Clear cut symptoms were obtained for N, K, Ca and Mg. The symptoms for P and S were uncleared. The growth rate of the cubiu plants was drastically affected by lack of N, P, K, followed by Ca and Mg. The omission of S from the nutrient solution did not affected the growth of the plants. The levels detected by chemical analysis of the leaves from "deficient" and "normal" plants were" N% = 2,02-3.53; P% = 0.12-0.20; K% = 0.84-3.44; Ca% = 0.22-2.64; Mg¾ = 0.07-0.48; 5¾ = 0.10-0.25.