The energetic cost of maintenance in ruminants: From classical to new concepts and prediction systems

The cost of maintenance makes up a large part of total energy costs in ruminants. Metabolizable energy (ME) requirement for maintenance (MEm) is the daily ME intake that exactly balances heat energy (HE). The net energy requirement for maintenance (NEm) is estimated subtracting MEm from the HE produced by the processing of the diet. Men cannot be directly measured experimentally and is estimated by measuring basal metabolism in fasted animals or by regression measuring the recovered energy in fed animals. MEm and NEm usually, but not always, are expressed in terms of BW0.75. However, this scaling factor is substantially empirical and its exponent is often inadequate, especially for growing animals. MEm estimated by different feeding systems (AFRC, CNCPS, CSIRO, INRA, NRC) were compared by using dairy cattle data. The comparison showed that these systems differ in the approaches used to estimate MEm and for its quantification. The CSIRO system estimated the highest MEm, mostly because it includes a correction factor to increase ME as the feeding level increases. Relative to CSIRO estimates, those of NRC, INRA, CNCPS, and AFRC were on average 0.92, 0.86, 0.84, and 0.78, respectively. MEm is affected by the previous nutritional history of the animals. This phenomenon is best predicted by dynamic models, of which several have been published in the last decades. They are based either on energy flows or on nutrient flows. Some of the different approaches used were described and discussed.

Comparação entre as necessidades energéticas prescritas e administradas a pacientes em terapia nutricional enteral

Objective: evaluating the adequacy, prescription and energy supply of enteral nutrition therapy in hospitalized patients. Methods: was performed a retrospective survey of the evolution of TNE protocol of 59 patients hospitalized in a general hospital in Marília / SP / BR. Data collected included gender, age, clinical diagnosis, anthropometric and dietary data related to the prescribed dietary formula, route and method of administration of the enteral nutrition, the daily volume prescribed and administered, the daily amount of energy required and offered in the diet, as well as possible complications. Body mass index (BMI), triceps skinfold (TSF) and arm muscle circumference (AMC) were used to establish the nutritional status of the patients. The adequacy of ENT was done according to the daily energy requirement compared to the average energy received during the daily use of ENT. Results: The average found to the BMI was 21.4 kg/m 2, and no differences were found comparing male and female. The data for TSF and AMC were different between genders (p<0.05) and suggest a more severe muscle mass in relation to adipose tissue. The averaged to the energy requirements was 1642 kcal/day but the average of energy prescribed was 1045 kcal/day and the amount offered was 1035 kcal/day. There was a significant difference between the necessity and the supplied energy offered through enteral nutrition (p=0.00) as well between the energy required and prescribed (p =0.00), both were shorter than the necessity. There was no significant difference (p>0.05) in energy supply, volume of enteral nutrition prescribed and administered among eutrophic, underweight or overweight patients. Conclusion: The results of this study indicate that the prescription and energy supply were not based on the needs of these patients, causing a significant energy deficit, which can lead to worsening of the nutritional status of the same. In hospitalized patients in use of ENT, the energy requirement must be made by a qualified professional within the multidisciplinary team, based on the needs of each patient.

Padrão alimentar de mulheres obesas que subnotificam ou não a ingestão energética

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exigências nutricionais de cabritas saanen em crescimento dos 30 aos 45 kg

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência do teor protéico da dieta hipocalórica e do sexo sobre a perda e posterior manutenção do peso em gatos obesos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da seleção para crescimento em diferentes idades sobre o consumo de energia em animais da raça Nelore

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Nível de fibra e tipo de processamento na digestibilidade, ingestão e parâmetros bioquímicos da arara-canindé (Ara ararauna L. – Aves, Psittacidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Composição corporal e exigências nutricionais de energia e proteína de tourinhos Santa Gertrudes confinados, recebendo alto concentrado e subproduto da produção de lisina

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise de propostas de sequestro mineral de carbono para usinas termoelétricas no Brasil

Pós-graduação em Engenharia Mecânica - FEG

Utilização de trocadores de calor de placas em espiral em processos da indústria siderúrgica

Stricter environmental policies are shown necessary to ensure an effective pollutant emission control. It is expected for the present year of 2015, that Brazil will assume, at the 21th United Nation's Climate Change Conference (COP21), implementation of commitment to a low carbon economy. This positioning affects the industrial environment, so that is deemed necessary to search for new technologies, less aggressive to the environment, so the adequacies to the new emission policies do not cause a negative effect on production. Almost all of the processes performed in the steel industry demand burning fuel and, therefore, flue gases are sent to the atmosphere. In this present work is discussed the utilization of heat exchangers so, by recovering part of the available heat from the flue gases of certain industrial process, the combustion air is preheated. The combustion air preheat results in less energy requirement, i.e., less need of fuel consumption and, in addition, minor amount of pollutants to be emitted. Due to better fitting to the process, it is studied the utilization of spiral plate heat exchangers. The heat exchanger dimensioning is made by an iterative method implemented in the software Microsoft Excel. Subsequently are analyzed the gains in terms of process's thermal efficiency improvement and the percentage of fuel saving. The latter implies in reduction of the same percentage of greenhouse gases emission

Utilização de trocadores de calor de placas em espiral em processos da indústria siderúrgica

Stricter environmental policies are shown necessary to ensure an effective pollutant emission control. It is expected for the present year of 2015, that Brazil will assume, at the 21th United Nation's Climate Change Conference (COP21), implementation of commitment to a low carbon economy. This positioning affects the industrial environment, so that is deemed necessary to search for new technologies, less aggressive to the environment, so the adequacies to the new emission policies do not cause a negative effect on production. Almost all of the processes performed in the steel industry demand burning fuel and, therefore, flue gases are sent to the atmosphere. In this present work is discussed the utilization of heat exchangers so, by recovering part of the available heat from the flue gases of certain industrial process, the combustion air is preheated. The combustion air preheat results in less energy requirement, i.e., less need of fuel consumption and, in addition, minor amount of pollutants to be emitted. Due to better fitting to the process, it is studied the utilization of spiral plate heat exchangers. The heat exchanger dimensioning is made by an iterative method implemented in the software Microsoft Excel. Subsequently are analyzed the gains in terms of process's thermal efficiency improvement and the percentage of fuel saving. The latter implies in reduction of the same percentage of greenhouse gases emission

Glucocorticoid and Estrogen Receptors Are Reduced in Mitochondria of Lung Epithelial Cells in Asthma

Mitochondrial glucocorticoid (mtGR) and estrogen (mtER) receptors participate in the coordination of the cell's energy requirement and in the mitochondrial oxidative phosphorylation enzyme (OXPHOS) biosynthesis, affecting reactive oxygen species (ROS) generation and induction of apoptosis. Although activation of mtGR and mtER is known to trigger anti-inflammatory signals, little information exists on the presence of these receptors in lung tissue and their role in respiratory physiology and disease. Using a mouse model of allergic airway inflammation disease and applying confocal microscopy, subcellular fractionation, and Western blot analysis we showed mitochondrial localization of GR alpha and ER beta in lung tissue. Allergic airway inflammation caused reduction in mtGR alpha, mtER beta, and OXPHOS enzyme biosynthesis in lung cells mitochondria and particularly in bronchial epithelial cells mitochondria, which was accompanied by decrease in lung mitochondrial mass and induction of apoptosis. Confirmation and validation of the reduction of the mitochondrial receptors in lung epithelial cells in human asthma was achieved by analyzing autopsies from fatal asthma cases. The presence of the mitochondrial GR alpha and ER beta in lung tissue cells and especially their reduction in bronchial epithelial cells during allergic airway inflammation suggests a crucial role of these receptors in the regulation of mitochondrial function in asthma, implicating their involvement in the pathophysiology of the disease.

(Table 1) Stage of the lemming cycle and nesting parameters of the greater snow geese between 1996-2005, Bylot Island

Resource pulses are common in various ecosystems and often have large impacts on ecosystem functioning. Many animals hoard food during resource pulses, yet how this behaviour affects pulse diffusion through trophic levels is poorly known because of a lack of individual-based studies. Our objective was to examine how the hoarding behaviour of arctic foxes (Alopex lagopus) preying on a seasonal pulsed resource (goose eggs) was affected by annual and seasonal changes in resource availability. We monitored foraging behaviour of foxes in a greater snow goose (Chen caerulescens atlanticus) colony during 8 nesting seasons that covered 2 lemming cycles. The number of goose eggs taken and cached per hour by foxes declined 6-fold from laying to hatching, while the proportion of eggs cached remained constant. In contrast, the proportion of eggs cached by foxes fluctuated in response to the annual lemming cycle independently of the seasonal pulse of goose eggs. Foxes cached the majority of eggs taken (> 90%) when lemming abundance was high or moderate but only 40% during the low phase of the cycle. This likely occurred because foxes consumed a greater proportion of goose eggs to fulfill their energy requirement at low lemming abundance. Our study clearly illustrates a behavioural mechanism that extends the energetic benefits of a resource pulse. The hoarding behaviour of the main predator enhances the allochthonous nutrients input brought by migrating birds from the south into the arctic terrestrial ecosystem. This could increase average predator density and promote indirect interactions among prey.

Análise da composição, abundância e distribuição da comunidade fitoplanctônica nos reservatórios do sistema em cascata do Médio e Baixo rio Tietê/SP

Com a finalidade de atender a demanda energética, muitos reservatórios foram construídos no Brasil e, notadamente na região Sudeste, as construções das barragens não somente atenderam aos usos múltiplos (geração de energia, irrigação, lazer e abastecimento público), como também foram elementos propulsores da economia regional, contribuindo para a expansão das atividades industriais e rurais, bem como, um desordenado crescimento urbano. Em conseqüência da falta de planejamento, áreas naturais foram desmatadas, sendo substituídas por formas de plantio inadequadas e por projetos de especulação imobiliária não condizentes com a sustentabilidade ambiental. No decorrer das últimas décadas, os impactos aumentaram em magnitude e extensão, ocasionando sérios problemas aos recursos hídricos, culminando em conflitos pelo uso da água. Dentro deste contexto, destaca-se o rio Tietê, o qual percorre importantes cidades e extensas áreas rurais no Estado de São Paulo, sendo que, neste longo percurso, recebe a contribuição de diversos tributários (poluídos ou não) e efluentes urbanos, industriais e aqueles derivados de fontes não pontuais, além do processo de fragmentação que foi instalado a partir da construção de inúmeras barragens. De forma conjunta, todos os fatores promoveram alterações significativas no sistema e, procurando avaliar a situação atual dos reservatórios, desenvolveu-se uma pesquisa direcionada à análise da composição, densidade e distribuição da comunidade fitoplanctônica e sua relação com as variáveis limnológicas, climatológicas e hidrodinâmicas dos reservatórios da Barra Bonita, Bariri, Ibitinga, Promissão, Nova Avanhandava, Três Irmãos, além dos rios Tietê e Piracicaba e parte do rio Paraná (reservatório de Jupiá e a Jusante do reservatório de Ilha Solteira). Para tanto, foram realizadas coletas nos meses de fevereiro, maio, julho e outubro de 2000 e os resultados obtidos demonstram uma elevada concentração de nutrientes, com redução na seqüência dos reservatórios, além da variabilidade temporal, com efeito significativo da precipitação no transporte de materiais, promovendo alterações no estado trófico de cada sistema. A disponibilidade de nutrientes, transparência da água, vazão e tempo de residência, associados aos fatores climatológicos, foram elementos importantes no estabelecimento das populações, influenciando a composição, densidade e distribuição da comunidade fitoplanctônica, a qual apresentou maior dominância das classes Cyanophyceae e Chlorophyceae, com maior contribuição em densidade e riqueza de espécies, respectivamente.

All-optical OFDM and distributed Raman amplification : challenges to enable high capacities and extend reach

We review recent advances in all-optical OFDM technologies and discuss the performance of a field trial of a 2 Tbit/s Coherent WDM over 124 km with distributed Raman amplification. The results indicate that careful optimisation of the Raman pumps is essential. We also consider how all-optical OFDM systems perform favourably against energy consumption when compared with alternative coherent detection schemes. We argue that, in an energy constrained high-capacity transmission system, direct detected all-optical OFDM with `ideal' Raman amplification is an attractive candidate for metro area datacentre interconnects with ~100 km fibre spans, with an overall energy requirement at least three times lower than coherent detection techniques.