Custos energéticos do agroecossistema pinhão-manso e milho: comparativo entre o sistema de condução sequeiro e o irrigado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação energética econômica da cultura do milho em assentamento rural, Iperó-SP

This paper, having as a hypothesis that greater energetic inputs don't keep ratio with economical outputs, has tried to study the economical and energetic flows in the maize cultivation to several production systems used in Ipanema Settling Area I, having as analysis instrument the indexes of Cultural, Energetic, Economical efficiency, which were added to the methodological proposal of Cultural Economical and Energetic Economical Efficiency indexes, built for probability settings. Four different systems have been identified: "A", "B", "C" and "D". The energetic expenditure were, respectively, 4,836.19 MJ x ha-1, 4,4647.17 MJ x ha-1, 4,639.49 MJ x ha-1 and 4,450.47 MJ x ha-1. In "A", where the use of machines is more intensive, the participation of biological source energy was 23.26%, whereas the ones of fossil origin are 76.74%. The "D" system has the greatest Cultural Efficiency, with average index of 16.26, whereas "A" showed the lowest Cultural Efficiency indexes, with average values of 14.83. For the analysis of the Energetic Efficiency, that indicates the dependence of energy from non renewable sources, the highest index was the "D" system with an average index of 53.84. The Economical Efficiency Indexes, which ranged from 1.84 to 1.96, show that all systems are efficient. The "D" system, with index equal to 8.84, showed the highest index of Economical Cultural efficiency. The Economical Energetic analysis for "A", "B", "C" and "D" systems, has resulted, respectively, in the following indexes: 21.14 ; 23.86 ; 22.87 and 29.26. Through the outcome analysis, it was concluded that the more intensive use of energy from nonrenewable sources ("A" system) didn't necessarily mean a higher efficiency when compared to "D" (labor intensive), what comes to prove the paper's initial hypothesis.

Avaliação energética econômica do agroecossistema algodão: uma abordagem entre sistemas familiares de produção do Paraguai e do Brasil

The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

Valiação energética e econômica do agroecossistema algodão: uma abordagem entre sistemas familiares de produção do Paraguai e Brasil

The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

Análise energética na agricultura: ferramenta importante para a produção agrícola mais sustentável

A produção de alimentos e matérias-primas é considerada um dos maiores desafios da atualidade. Assim, os impactos gerados pela atividade da agricultura são muitos, como por exemplo, erosão dos solos, poluição de águas doces e geração de resíduos. Com isso faz-se necessário o desenvolvimento de tecnologias para promover a redução desses impactos. O presente trabalho tem como objetivo apresentar e discutir análises energéticas em sistemas de produção agrícola como uma ferramenta capaz de destacar a dependência dos agroecossistemas de energia externa e de fontes não renováveis, particularmente de fontes fósseis. Assim, com o uso dessa ferramenta, alternativas para uma produção agrícola com menos impacto ambiental pode ser alcançada, proporcionando a ampliação das possibilidades para uma produção mais sustentável.

Demanda energética em diferentes manejos de solo e híbridos de milho

This study aimed to account the energy balance of six different farming systems: CMT (minimum tillage with transgenic corn); CMNT (minimum tillage with non-transgenic corn); PCT (conventional tillage with transgenic corn); PCNT (conventional tillage with non-transgenic corn); PDT (no-tillage system with transgenic corn) and PDNT (no-tillage system with non-transgenic corn). The study was carried out at the Experimental Farm Lageado FCA/Unesp, Botucatu - SP. The energy balance was performed by subtracting the total energy inputs by the total energy output. Energy efficiency was calculated by dividing the total energy output by the total energy inputs. The total values ​​of energy inputs and outputs were expressed in MJ.ha-1 (mega joules per hectare). To calculate the energy inputs were accounted the fuel consumption and lubricants, depreciation energy of machinery and implements, manpower and agricultural inputs. The energy outputs were calculated according to the maize yield. The result shows that the system PDT was the system that had better energy efficiency and the system that had the lowest efficiency was the PCT system. The system with lower energy demand was the PDT and the greatest demand was PCNT.

Determinação do valor energético em bebidas de maracujá

The objective of this work was to calculate the energetic values in passion fruit commercial beverages (whole juices, reconstituted juices, tropical juices, and nectars) by their centesimal composition. Then, the energetic values were compared to the caloric values as described on the nutritional facts from the beverageslabels. Analyses of moisture, protein, lipids, ashes, and carbohydrates were done in 25 commercialbeverages samples. In order to calculate the energetic value of each sample, the following conversion factors were used: 4 kcal.g-1 for carbohydrates, 4 kcal.g-1 for proteins and 9 kcal.g-1 for lipids. To allow the comparison of the results, the energetic values printed on the labels were converted into kcal.100g-1 usingthe beverages density. Overall, the commercial beverages calculated energetic values were similar to the nutritional facts.

Conteúdo energético das operárias da formiga cortadeira, Atta sexdens

The knowledge of the workers energy content is essential to measure the energy availability for maintenance and performance of activities essences for the colony growth. But little is known about the workers energy content, and how much will be available to carry out activities, for example, the excavation of the nest. The present study determined the lipid content and energy content of the worker ants inactive before and after excavation activity. Through the lipids determination, it can be calculated the energy content of workers resting (standing) with those which excavated. The lipid content and energy content of the workers were on average 9.1±0.8% and energy content of the workers was on average 111.31±54.71J, respectively, however, the experimental series did not differ significantly. Additionally, catabolic flux rate based in workers body mass was 14.76±10.11µW. It was concluded that the energy resource for the excavation of the nest is not coming from reserve lipid body, and thus the energy content of the workers did not change before and after excavation activity.

Análise energética do milho em sistema de plantio direto, no assenta-mento rural da fazenda pirituba, Itaberá/SP

The aim of this work was to proceed, from the energetic point of view, an analysis of a corn agroecosystem, on the direct planting, located at Pirituba II rural workers placement project, Área III, city of Itaberá/SP. The energetic analysis mesured all operations, together with its fisical demands, the inputs and produced grains, classifying them within their respective flux, based on the definition of energy inputs and outputs, converting them into energetic equivalents and, so, determining the energetic matrix of de agroecosystem. The caloric index used were cultural efficiency and cultural liquid energy. The results showed the dependence of the studied systems on the chemical energy sources, from fertilizers (39,49%), agrotoxics (27,74%), and fossile energy of diesel (24,94%). The energetic values of the direct and indirect energy showed a very big difference between them, what means that the energy sources used in the system are not balanced. The cultural efficiency found was 12,86 and cultural liquid energy got to 115.025,92 MJ x ha-1. Later on, obtained data was compared to already existing data in Bueno (2002), who researched conventional planting system. The cultural inputs of both systems were energeticaly different: 9.696,97 MJ x ha-1 (direct planting), e 8.783,78 MJ x ha-1 (convencional planting). The outputs had very different results: 124.722,89 e 79.118,38 MJ x ha-1, respectively. So, we had much more cultural liquid energy on the studied system: 115.025,92 MJ x ha-1, compared to convencional system: 70.334,60 MJ x ha-1. The energectic loss of nitrogened fertilizers contributed for the high energetic loss of both energetic studied matrices. There are few contribution from biological energy source in both systems.

Avaliação do gasto energético de repouso em pacientes com sepse associada ou não à lesão renal aguda

Pós-graduação em Fisiopatologia em Clínica Médica - FMB

Aproveitamento energético de uma planta de sulfatação

Pós-graduação em Engenharia Mecânica - FEG

Fibra, metabolismo ácido-básico e balanço de macroelementos em gatos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Eficiência da utilização e turnover do nitrogênio da L-(15N) treonina em tecidos de frango de corte

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Viabilidade técnica e econômica da incorporação do balanço eletrolítico na formulação de rações para poedeiras em segundo ciclo de produção

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Custo energético durante a prática do Kendō e proposição de protocolo específico para avaliação da aptidão aeróbia em praticantes

Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC