Resumo O conhecimento sobre a quantidade de nutrientes exportados por frutas cítricas é uma ferramenta adequada para estimar a reposição de nutrientes, e estas informações para tangerinas são escassas. Nesse contexto, o objetivo deste estudo foi determinar o teor e a exportação de nutrientes pela colheita de frutos de tangerineiras, em um pomar manejado sob sistema orgânico de produção. Um experimento foi realizado em um pomar orgânico de tangerineiras adultas (23 anos), localizado no Rio Grande do Sul, Brasil. O teor total de macronutrientes e de micronutrientes foi determinado nos frutos de tangerina, e a exportação foi estimada pela produtividade média de duas safras (2013/2014 e 2014/2015). A exportação média de macronutrientes foi de 3,3; 2,3; 1,3; 0,4 e 0,3 kg t-1 para N, K, Ca, P e Mg, respectivamente; e de micronutrientes foi de 6,3; 4,6; 1,5; 0,7 e 0,5 g t-1 para Fe, B, Zn, Mn e Cu, respectivamente. A exportação de N pelas tangerinas não condiz com as informações atuais utilizadas para recomendações de adubação em citros, sendo o K o elemento mais exportado. Em relação aos micronutrientes, além de as quantidades exportadas variarem entre a literatura, a ordem de magnitude segue a mesma observada em nosso estudo. Propomos esses novos padrões para reposição de macronutrientes e de micronutrientes em pomares estabelecidos de tangerina sob manejo orgânico, contribuindo para uma recomendação de adubação mais precisa.

Abstract The knowledge on the amount of nutrients exported by citrus fruit is an adequate tool to estimate nutrient demand reposition and this information about mandarin is very scarce. In this context, the objective of this study was to determine the nutrient content and exportation by mandarin fruits harvest, in an orchard managed under organic production system. An experiment was carried out in an organic orchard of adult mandarin trees (23 years), located in Rio Grande do Sul State (Brazil). The total content of macronutrients and micronutrients was determined in the mandarin fruits and the exportation was estimated by average yields in two seasons (2013/2014 and 2014/2015). The average exportation of macronutrient was 3.3, 2.3, 1.3, 0.4 and 0.3 kg t-1 for N, K, Ca, P and Mg, respectively; and of micronutrients was 6.3, 4.6, 1.5, 0.7 and 0.5 g t-1 for Fe, B, Zn, Mn and Cu, respectively. The N exportation in mandarin fruits does not comply with the current information used for citrus fertilizer recommendations, where the K is the nutrient most exported. Regarding micronutrients, besides the exported amounts vary among the literature, the magnitude order follows the same observed in our study. We propose these new standards for reposition of macronutrients and micronutrients in established mandarin orchards under organic management, contributing to a more accurate fertilizer recommendation.

Abstract Objective This study aims to evaluate bone repair and the development of the medication related osteonecrosis of the jaw (MRONJ) associated with the use of zoledronic acid in Wistar rats. Methodology 48 male Wistar rats were divided into four groups: ZA, treated with intraperitoneal zoledronic acid, 0.6 mg/kg every 28 days, totaling five doses; control (C), treated with 0.9% sodium chloride; ZA-surgical (SZA) and C-surgical (SC), submitted to extraction of the right upper molars 45 days after the first application. Alveolar bone repair was evaluated by macroscopic and histological analysis. Protein expression evaluations were performed by qPCR. Results Macroscopic evaluation showed that 91.66% (11) of the animals in the SZA group and 41.66% (5) from the SC group presented solution of epithelium continuity (P<0.05). All animals in the SZA group and none in the SC group had bone sequestration. The area of osteonecrosis was higher in the SZA group than in the SC group (P<0.05). In molecular evaluation, the SZA group presented changes in the expression of markers for osteoclasts, with increased RANK and RANKL, and a decrease in OPG. Conclusion The results highlighted strong and evident interference of zoledronic acid in bone repair of the socket, causing osteonecrosis and delayed bone remodeling.

This study evaluated the performance of 21 beef cattle modal production systems that conduct only the raising phase. These production systems were developed in 21 municipalities in seven Brazilian states. We used two different DEA BCC models, corresponding to different points of view. Firstly we used an economic model that measured the ability of a production system to generate revenue with the preservation of native forest, using labor, capital, and current spending as inputs. The socio-environmental approach, corresponding to the second BCC model, uses the production factor labor as an output. In that model our interest was to assess whether the capital costs generate economic, environmental, and social benefits. Weight restrictions were imposed on the output variables of each model to explain the proposed viewpoints and to avoid inconsistent results. The results pointed out sources of inefficiency in terms of labor with low qualification, and use of bulls of questionable quality, factors that are common in extensive systems. These are some of the major bottlenecks in animal production systems as a whole.

Neste artigo propõe-se analisar comparativamente o desempenho de sistemas de produção modais de pecuária extensiva de corte na fase de cria em 21 municípios brasileiros. A cria é a fase da atividade que sustenta toda a cadeia de produção da pecuária de corte. É usado o modelo de análise envoltória de dados (DEA) com retornos variáveis de escala. O objetivo é medir o desempenho da decisão do produtor em relação à composição do sistema produtivo. As variáveis usadas são número de reprodutores, quantidade de bezerros e vacas de descarte. Dos 21 sistemas avaliados, quatro foram DEA BCC eficientes e a maioria dos sistemas avaliados opera na região de retornos crescentes de escala.

In this article, the performance of extensive livestock modal production systems was analyzed comparatively during its rearing phase in 21 Brazilian municipalities. This phase constitutes the activity that sustains the entire livestock production chain. Data envelopment analysis (DEA) models were used with variable returns to scale. The objective was to measure the performance of the producer's decision regarding the composition of the production system. The number of bull breeders, number of calves and number of cull cows were the variables used. Four of the 21 systems evaluated were DEA efficient and most of them were operating under increasing returns to scale.

The cow-calf beef production sector in Brazil has a wide variety of operating systems. This suggests the identification and the characterization of homogeneous regions of production, with consequent implementation of actions to achieve its sustainability. In this paper we attempted to measure the performance of 21 livestock modal production systems, in their cow-calf phase. We measured the performance of these systems, considering husbandry and production variables. The proposed approach is based on data envelopment analysis (DEA). We used unitary input DEA model, with apparent input orientation, together with the efficiency measurements generated by the inverted DEA frontier. We identified five modal production systems typologies, using the isoefficiency layers approach. The results showed that the knowledge and the processes management are the most important factors for improving the efficiency of beef cattle production systems.

OBJETIVO: Relatar o caso de uma criança com neurofibromatose do tipo 1, apresentando o achado ocasional de múltiplas hiperintensidades e de lesão hamartomatosa pré-quiasmática no sistema nervoso central. DESCRIÇÃO DO CASO: Menino de tez escura de quatro anos, cujo pai apresentava manchas café-com-leite e história de cirurgia de tumor de ouvido. A criança evoluiu com um adequado desenvolvimento neuropsicomotor, sem crises convulsivas ou déficit de aprendizagem. Ao exame físico, possuía múltiplas manchas café-com-leite e efélides. A avaliação pela ressonância nuclear magnética de encéfalo evidenciou múltiplas imagens nodulares hiperintensas em T2 e Flair, com isossinal em T1, localizadas na substância branca dos hemisférios cerebrais, cerebelo e tronco cerebral. Apresentava ainda lesão hamartomatosa pré-quiasmática. A avaliação eletroencefalográfica e o exame neurológico eram normais. COMENTÁRIOS: As imagens hiperintensas verificadas na ressonância nuclear magnética correspondem aos chamados unidentified bright objects (UBOs), observados em de 60 a 70% das crianças com neurofibromatose do tipo 1, sendo raros em adultos. Sua etiologia e significado clínico ainda não são claros. Alguns estudos os têm associado à disfunção cognitiva, déficit neurológico e risco de malignização. Hamartomas localizados próximos ao quiasma óptico são incomuns, mas podem se relacionar à puberdade precoce. A avaliação do sistema nervoso central de crianças assintomáticas com neurofibromatose do tipo 1 é discutível. Contudo, nos casos em que UBOs sejam identificados, é importante considerar seu seguimento radiológico, especialmente diante de lesões múltiplas ou atípicas.

OBJECTIVE:To report a child with neurofibromatosis type 1 presenting the occasional central nervous system feature of multiple hyperintensities and a prechiasmatic hamartomatous lesion. CASE DESCRIPTION: The patient is a four-year old black boy whose father presented cafe-au-lait spots and history of ear tumor surgery. The neuropsychomotor development of the child was within the normal range, without seizures or learning deficit. At the physical exam, he had several cafe-au-lait spots and freckles. The magnetic resonance image showed multiple nodular and hyperintense images in T2 and Flair, with isosignal in T1, localized in the white matter of cerebellum, brainstem and cerebral hemispheres. A prechiasmatic hamartomatous lesion was also noted. Electroencephalographic evaluation and the neurological exam were normal. COMMENTS: The hyperintensities images verified in the magnetic resonance image corresponded to the "unidentified bright objects" (UBOs). They are observed in 60 to 70% of the children with neurofibromatosis type 1, being rare in adults. Its etiology and clinical meaning are still not clear. Some studies have associated them to cognitive dysfunction, neurological deficit and risk of malignization. Hamartomas close to the optic chiasm are unusual, but they can be related to early puberty. Central nervous system imaging of asymptomatic neurofibromatosis type 1 children is controversial. However, in cases in which UBOs are occasionally identified, it is important to consider their radiological follow-up, especially in the presence of multiple and atypical lesions.