The kinetic study of orange peel combustion has been conducted using experimental results of the termogravimetric analysis. This study made use of several equations: Coats (integral), Sharp y Achar (differentials) and Isoconversion (free kinetic). By means of the combination of these equations, the kinetic results for natural materials are more reliable. The final kinetic models are D4-D2 for dehydration, decompositions of hemicellulose and cellulose by D4, and F1 for lignin. The rank of energy activation ranges 80-90 kJ/mol (kinetic free) and 48-162 kJ/mol (model fitting method) because simultaneous reactions occur.

Se realiza el estudio cinético de la combustión de la cáscara de naranja, a partir de resultados experimentales de análisis termogavimétrico (ATG). El mismo se efectúa combinando varias metodologías de cálculo: las ecuaciones de Coats (integral), Sharp y Achar (diferenciales) e isoconversión (Cinética libre). Al combinar dichas metodologías se logra resultados cinéticos más confiables, esencial para el tratamiento de materiales naturales. La combustión de la cáscara de naranja transcurre mediante modelos cinéticos D4-D2 para la deshidratación, la descomposición de la hemicelulosa y celulosa por el modelo difusivo D4 y para la lignina F1, en ambas velocidades de calentamiento. Los valores de la energía de activación se comportaron en un rango de valores entre 80-90 kJ/mol para isoconversión y 48-162 kJ/mol por ajuste de las funciones, lo que se justifica por la ocurrencia de reacciones simultáneas. Se demuestra la menor influencia de la velocidad de calentamiento en los resultados cinéticos precisados.

Introduction: The prevalence of portal vein thrombosis (PVT) in patients that have undergone liver transplantation (LT) is 9.7% (SD 4.5). The aim of our study was to determine the prevalence, assess the factors that are associated with PVT and clarify their association with prognosis in patients with liver cirrhosis (LC) and LT. Aims and methods: From 2005 to 2014, laboratory, radiological and surgical data were collected from patients with LC in our center who had undergone LT for the first time. Results: One hundred and ninety-one patients were included. The mean age was 55 (SD 9), 75.4% of patients were male and 48.7% had HCV. The Child-Pugh scores were A/B/C 41.9%/35.9%/25.5% and the MELD score was 15 (SD 6). Previous decompensations were: ascites (61.4%), hepatic encephalopathy (34.4%), variceal bleeding (25.4%), hepatocellular carcinoma (48.9%) and spontaneous bacterial peritonitis (SPB) (14.3%). The mean post-transplant follow-up was 42 months (0-113). PVT was diagnosed at LT in 18 patients (9.4%). Six patients were previously diagnosed using imaging tests (33.3%): 2 patients (11.1%) by DU and 4 patients (22.2%) by CT scan. All patients with PVT had DU in a mean time of 6 months before LT (0-44) and 90 patients (47.1%) had a CT scan in a median time of 6 months before LT (0-45). PVT was significantly related to the presence of SBP (33.3% vs 12.6%; p = 0.02) and lower levels of albumin (3.1g/dl vs 3.4g/dl; p = 0.05). MELD was higher in patients with PVT (16.6 vs 14.9; p = 0.3). There were no significant differences with regard to the need for transfusion of blood components. Moreover, the surgery time was similar in both groups. PVT correlated with a higher mortality in the first 30 days (8.8% vs 16.7%; p = 0.2). Conclusion: Prior history of SBP and lower levels of albumin were identified as factors associated with PVT. The pre-transplant diagnosis rate is very low and the presence of PVT may have implications for short-term mortality.

Este trabalho descreve a composição florística na área do reservatório da futura Hidrelétrica de Cachoeira Porteira - PA (localizada na margem esquerda do rio Trombetas), e a caracterização da vegetação. São apresentados dados sobre a abundância, dominância, freqüência e os Índices de Valor de Importância das espécies (IVIE) e o Índice de Valor de Importância das Famílias (IVIF) e a análise da estrutura horizontal da floresta. Os estudos desenvolvidos neste trabalho mostram as espécies e famílias mais importantes da área com relação a sua influência, na definição do perfil estrutural da floresta, além da identificação dos diferentes tipos de vegetação. Os 13 hectares de floresta inventariados sustentam 4.583 indivíduos, abrangendo árvores, palmeiras e cipós com DAP > 10cm, distribuídos em 359 espécies, 217 gêneros e 55 famílias (três medidas de importância ecológica; abundância, dominância e freqüência, expressas como três porcentagens, foram somadas para obter um Índice de Valor de Importância (IVIE) das espécies). As duas espécies com os maiores IVIE, em toda a área estudada pesquisada, foram Eschweilera coriacea (DC) S. A . Mori, com 15,24% e Micropholis guyanensis (A . DC.) Pierre com 10,87%. As famílias que apresentaram os maiores Índices de Valor de Importância (IVIF) nos 13 hectares, foram Caesalpiniaceae (31,45%) e Sapotaceae (30,34%).

This work describes the floristic composition in the future Cachoeira Porteira UHE-PA water reservoir area (located on the left margin of the Trombetas river), and the characterization of the vegetation. Data on abundance, dominance, frequency, Species Importance Value Indexes (IVIE), Family Importance Value Index (IVIF), and forest horizontal structure analysis, are presented in the present study. The studies developed in this work show the area's most important species and families, according to their influence on the forest structural profile definition, in addition to the identification of vegetation different types. The 13 surveyed forest hectares support 4.583 individuals, comprising trees, palms and lianas with DAP > 10cm, distributed in 359 species, 217 genera and 55 families (Three measures of ecological importance were totaled to give an Importance Value Index (IVIE) of the species). The two species with the highest IVIE, in all surveyed area, were Eschweilera coriacea (DC) S. A. Mori, with 15,24% and Micropholis guyanensis (A. DC) Pierre, with 10,87%. Families presenting the highest Importance Value Indexes (IVIF) in the 13 hectares, were Caealpiniaceae (31,45%) and Sapotaceae (30,34%).

Neste trabalho estudou-se a regeneração natural de três hectares, em floresta ombrófila de terra - firme na região do rio Urucu no município de Coari -Am ( 40 51' 18" e 40 52' 16" S; 650 17' 58" e 650 20' 01" W), abordando todos os indivíduos com altura total maior ou igual a 10cm até 3,0m e diâmetro à altura do peito (DAP) menor que 10cm. As espécies que mais se destacaram foram o Protium subserratum Engl. com valores médios de 30,55%, Inga receptabilis (Vahl.) Wild.com 15,85%, Oenocarpus bacaba com 12,35% e Oenocarpus bataua com 11,42%, entre as espécies arbóreas.

Natural regeneration was studied of three hectares of "terra firme" in Coari Amazonas State, Brazil ( 40 51' 18" e 40 52' 16" S; 650 17' 58" e 650 20' 01"W) forest all individuals of height 0,1 - 3,0m and DBH less than 10cm.In the natural regeneration Protium subserratum Engl. stood out, with average values of 30,55% and Inga receptabilis (Vahl.) Wild. with 15,85%, Oenocarpus bacaba with 12,35% and Oenocarpus bataua with 11,42%, this among the arborescent species.

O presente trabalho teve por objetivo principal caracterizar a vegetação da área de exploração de petróleo da PETROBRAS, no rio Urucu, bem como dar subsídios para a utilização da floresta de forma organizada e produtiva, baseada em conhecimentos científicos, de modo não somente a produzir resultados econômicos mas principalmente conservar o ambiente. Os três hectares de floresta inventariada sustentam 2.241 indivíduos, abrangendo árvores, palmeiras e cipós com DAP> 10 cm, distribuídos em 577 espécies, 225 gêneros e 60 famílias. Três medidas de importância ecológica — abundância, dominância e freqüência — expressas como três porcentagens, foram somadas para obter um índice de Valor de Importância (IVI). As duas espécies com os maiores IV1E, em toda a área pesquisada, foram Eschweilera coriacea (DC.) S. A. Mori, com 15% no hectare 2 e E. wachenheimii (Benoist) Sandwith, com 14% no hectare 3. As famílias que obtiveram os maiores índices de Valor de Importância (IVIF), em média, nos 3 hectares, foram Lecythidaceae (51,6%), Sapotaceae (40,2%) e Chrysobalanaceae (24,6%).

The aim of this paper is to characterize forest vegetation in the Urucu River region, a petroleum drilling area of PETROBRAS. This information may contribute to the organized and productive use of the forest, based on scientific knowledge, so that economic returns can be obtained while conserving the environment. All tree, vine and palm stems over 10 cm DBH were inventoried in three hectares. A total of 2241 individuals were found in 60 families, 225 genera and 577 species or morphospecies. Three measures of ecological importance — abundance, dominance and frequency — expressed as three separate percentages were summed to give an Importance Value Index (IVIE). The two highest IVI were for Eschweilera coracea (DC.) S. A. Mori, with 15% in hectare 2, and E. wachenheimii (Benoist) Sandwith, with 14% in hectare 3. The highest Family Importance Indices averaged across the three hectares were for Lecythidaceae (51.62%), Sapotaceae (40.24%) and Chrysobalanacaeae (24.56%).