990 resultados para Energy scenario
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BACKGROUND: Obesity is becoming more frequent in children; understanding the extent to which this condition affects not only carbohydrate and lipid metabolism but also protein metabolism is of paramount importance. OBJECTIVE: We evaluated the kinetics of protein metabolism in obese, prepubertal children in the static phase of obesity. DESIGN: In this cross-sectional study, 9 obese children (x +/- SE: 44+/-4 kg, 30.9+/-1.5% body fat) were compared with 8 lean (28+/-2 kg ,16.8+/-1.2% body fat), age-matched (8.5+/-0.2 y) control children. Whole-body nitrogen flux, protein synthesis, and protein breakdown were calculated postprandially over 9 h from 15N abundance in urinary ammonia by using a single oral dose of [15N]glycine; resting energy expenditure (REE) was assessed by indirect calorimetry (canopy) and body composition by multiple skinfold-thickness measurements. RESULTS: Absolute rates of protein synthesis and breakdown were significantly greater in obese children than in control children (x +/- SE: 208+/-24 compared with 137+/-14 g/d, P < 0.05, and 149+/-20 compared with 89+/-13 g/d, P < 0.05, respectively). When these variables were adjusted for fat-free mass by analysis of covariance, however, the differences between groups disappeared. There was a significant relation between protein synthesis and fat-free mass (r = 0.83, P < 0.001) as well as between protein synthesis and REE (r = 0.79, P < 0.005). CONCLUSIONS: Obesity in prepubertal children is associated with an absolute increase in whole-body protein turnover that is consistent with an absolute increase in fat-free mass, both of which contribute to explaining the greater absolute REE in obese children than in control children.
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This study analyzes the impact of price shocks in three input and output markets critical to ethanol: gasoline, corn, and sugar. We investigate the impact of these shocks on ethanol and related agricultural markets in the United States and Brazil. We find that the composition of a country’s vehicle fleet determines the direction of the response of ethanol consumption to changes in the gasoline price. We also find that a change in feedstock costs affects the profitability of ethanol producers and the domestic ethanol price. In Brazil, where two commodities compete for sugarcane, changes in the sugar market affect the competing ethanol market.
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OBJECTIVE: A new tool to quantify visceral adipose tissue (VAT) over the android region of a total body dual-energy x-ray absorptiometry (DXA) scan has recently been reported. The measurement, CoreScan, is currently available on Lunar iDXA densitometers. The purpose of the study was to determine the precision of the CoreScan VAT measurement, which is critical for understanding the utility of this measure in longitudinal trials. DESIGN AND METHODS: VAT precision was characterized in both an anthropomorphic imaging phantom (measured on 10 Lunar iDXA systems) and a clinical population consisting of obese women (n = 32). RESULTS: The intrascanner precision for the VAT phantom across 9 quantities of VAT mass (0-1,800 g) ranged from 28.4 to 38.0 g. The interscanner precision ranged from 24.7 to 38.4 g. There was no statistical dependence on the quantity of VAT for either the inter- or intrascanner precision result (p = 0.670). Combining inter- and intrascanner precision yielded a total phantom precision estimate of 47.6 g for VAT mass, which corresponds to a 4.8% coefficient of variance (CV) for a 1 kg VAT mass. Our clinical population, who completed replicate total body scans with repositioning between scans, showed a precision of 56.8 g on an average VAT mass of 1110.4 g. This corresponds to a 5.1% CV. Hence, the in vivo precision result was similar to the phantom precision result. CONCLUSIONS: The study suggests that CoreScan has a relatively low precision error in both phantoms and obese women and therefore may be a useful addition to clinical trials where interventions are targeted towards changes in visceral adiposity.
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OBJECTIVE To analyze scientific production about workplace bullying and harassment in dissertations and theses in Brazil, with emphasis on the year of publication; educational institution; area of knowledge; professional and academic background of the authors; keywords used; and concept map organization. METHOD Bibliometric study with a quantitative approach with a sample consisting of 57 papers, 5 theses and 52 dissertations, published between 2002 and 2012. RESULTS It was found that 2012 was the year with the highest number of publications in this topic area. The region that stood out was the Southeast. The institution with the highest number of publications was the Federal University of Santa Catarina. There was a predominance of dissertations and most publications were produced by researchers focused on a multidisciplinary perspective. CONCLUSION Expanding the views regarding bullying in order to disseminate scientific production was proposed, promoting further advancement of debates and raising pertinent questions.
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Small daily positive energy imbalances of 200 to 800 kJ (about 50 to 200 kcal) due to reduced resting energy expenditure (REE), reduced diet-induced thermogenesis, or physical inactivity are believed to predispose to obesity. However, estimates of the magnitude of the weight gain often fail to account for concurrent changes in body composition and increases in maintenance energy requirements as weight increases and energy equilibrium is re-established. Using previously reported data on body composition and REE in women and the energy cost of tissue deposition, we used mathematical models to predict the theoretical effect of a persistent reduction in energy expenditure on long-term weight gain, assuming no adaptation in energy intake. The analyses indicate the following effects of a reduced level of energy expenditure in lean and obese women: (i) REE rises more slowly with increasing degrees of obesity due to a declining proportion of the more metabolically active fat-free mass; so, for the same positive energy balance, a significantly greater weight gain is expected for obese than for lean women before energy equilibrium is re-established; (ii) due to the greater energy density of adipose tissue, the time course of weight gain to achieve energy balance is longer for obese subjects: in general, this is approximately five years for lean and ten years for obese women; (iii) the magnitude of weight gain of lean women in response to a reduced energy expenditure of 200 to 800 kJ/day is only about 3 to 15 kg, amounts insufficient to explain severe obesity.
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Projections of U.S. ethanol production and its impacts on planted acreage, crop prices, livestock production and prices, trade, and retail food costs are presented under the assumption that current tax credits and trade policies are maintained. The projections were made using a multi-product, multi-country deterministic partial equilibrium model. The impacts of higher oil prices, a drought combined with an ethanol mandate, and removal of land from the Conservation Reserve Program (CRP) relative to baseline projections are also presented. The results indicate that expanded U.S. ethanol production will cause long-run crop prices to increase. In response to higher feed costs, livestock farmgate prices will increase enough to cover the feed cost increases. Retail meat, egg, and dairy prices will also increase. If oil prices are permanently $10-per-barrel higher than assumed in the baseline projections, U.S. ethanol will expand significantly. The magnitude of the expansion will depend on the future makeup of the U.S. automobile fleet. If sufficient demand for E-85 from flex-fuel vehicles is available, corn-based ethanol production is projected to increase to over 30 billion gallons per year with the higher oil prices. The direct effect of higher feed costs is that U.S. food prices would increase by a minimum of 1.1% over baseline levels. Results of a model of a 1988-type drought combined with a large mandate for continued ethanol production show sharply higher crop prices, a drop in livestock production, and higher food prices. Corn exports would drop significantly, and feed costs would rise. Wheat feed use would rise sharply. Taking additional land out of the CRP would lower crop prices in the short run. But because long-run corn prices are determined by ethanol prices and not by corn acreage, the long-run impacts on commodity prices and food prices of a smaller CRP are modest. Cellulosic ethanol from switchgrass and biodiesel from soybeans do not become economically viable in the Corn Belt under any of the scenarios. This is so because high energy costs that increase the prices of biodiesel and switchgrass ethanol also increase the price of cornbased ethanol. So long as producers can choose between soybeans for biodiesel, switchgrass for ethanol, and corn for ethanol, they will choose to grow corn. Cellulosic ethanol from corn stover does not enter into any scenario because of the high cost of collecting and transporting corn stover over the large distances required to supply a commercial-sized ethanol facility.
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The Low-Income Home Energy Assistance Program (LIHEAP) and Weatherization Program Interim Study Committee was created by the Legislative Council and charged to review issues involving the Low-Income Home Energy Assistance Program (LIHEAP) and Weatherization Program including financial assistance, the application and intake processes, the community action agencies' assessment and resolution proposal, and whether to involve the Department of Human Services in the administration of the programs to enable low-income persons to access additional assistance programs through a single location.
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Newsletter produced by Iowa Department of Natural Resources about energy and waste in Iowa
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Rockfall hazard zoning is usually achieved using a qualitative estimate of hazard, and not an absolute scale. In Switzerland, danger maps, which correspond to a hazard zoning depending on the intensity of the considered phenomenon (e.g. kinetic energy for rockfalls), are replacing hazard maps. Basically, the danger grows with the mean frequency and with the intensity of the rockfall. This principle based on intensity thresholds may also be applied to other intensity threshold values than those used in Switzerland for rockfall hazard zoning method, i.e. danger mapping. In this paper, we explore the effect of slope geometry and rockfall frequency on the rockfall hazard zoning. First, the transition from 2D zoning to 3D zoning based on rockfall trajectory simulation is examined; then, its dependency on slope geometry is emphasized. The spatial extent of hazard zones is examined, showing that limits may vary widely depending on the rockfall frequency. This approach is especially dedicated to highly populated regions, because the hazard zoning has to be very fine in order to delineate the greatest possible territory containing acceptable risks.
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This paper presents 3-D brain tissue classificationschemes using three recent promising energy minimizationmethods for Markov random fields: graph cuts, loopybelief propagation and tree-reweighted message passing.The classification is performed using the well knownfinite Gaussian mixture Markov Random Field model.Results from the above methods are compared with widelyused iterative conditional modes algorithm. Theevaluation is performed on a dataset containing simulatedT1-weighted MR brain volumes with varying noise andintensity non-uniformities. The comparisons are performedin terms of energies as well as based on ground truthsegmentations, using various quantitative metrics.
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In this paper we evaluate the quantitative impact that a number ofalternative reform scenarios may have on the total expenditure for publicpensions in Spain. Our quantitative findings can be summarized in twosentences. For all the reforms considered, the financial impact of themechanical effect (change in benefits) is order of magnitudes larger thanthe behavioral impact or change in behavior. For the two Spanish reforms,we find once again that their effect on the outstanding liability of theSpanish Social Security System is essentially negligible: neither themechanical nor the behavioral effects amount to much for the 1997 reform,and amount to very little for the 2002 amendment.
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In the absence of comparable macroeconomic indicators for most of the Latin Americaneconomies before the 1930s, the apparent consumption of energy is used in this paper as a proxyof the degree of modernisation of Latin America and the Caribbean. This paper presents anestimate of the apparent consumption per head of modern energies (coal, petroleum andhydroelectricity) for 30 countries of Latin American and the Caribbean for 1890 to 1925,multiplying the number of countries for which energy consumption estimates were previouslyavailable. As a result, the paper provides the basis for a quantitative comparative analysis ofmodernisation performance beyond the few countries for which historical national accounts areavailable in Latin America.
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Epidemiological studies indicate that the consumption of fructose-containing caloric sweeteners (FCCS: mainly sucrose and high-fructose corn syrup) is associated with obesity. The hypothesis that FCCS plays a causal role in the development of obesity however implies that they would impair energy balance to a larger extent than other nutrients, either by increasing food intake, or by decreasing energy expenditure. We therefore reviewed the literature comparing a) diet-induced thermogenesis (DIT) after ingestion of isocaloric FCCS vs glucose meals, and b) basal metabolic rate (BMR) or c) post-prandial energy expenditure after consuming a high FCCS diet for > 3 days vs basal,weight-maintenance low FCCS diet. Nine studies compared the effects of single isocaloric FCCS and glucose meals on DIT; of them, six studies reported that DIT was significantly higher with FCCS than with glucose, 2 reported a non-significant increase with FCCS, and one reported no difference. The higher DIT with fructose than glucose can be explained by the low energy efficiency associated with fructose metabolism. Five studies compared BMR after consumption of a high FCCS vs a low FCCS diet for > 3 days. Four studies reported no change after 4-7 day on a high FCCS diet, and only one study reported a 7% decrease after 12 week on a high FCCS diet. Three studies compared post-prandial EE after consumption of a high FCCS vs a low FCCS diet for > 3 days, and did not report any significant difference. One study compared 24-EE in subjects fed a weight-maintenance diet and hypercaloric diets with 50% excess energy as fructose, sucrose and glucose during 4 days: 24-EE was increased with all 3 hypercaloric diets, but there was no difference between fructose, sucrose and glucose. We conclude that fructose has lower energy efficiency than glucose. Based on available studies, there is presently no hint that dietary FCCS may decrease EE. Larger, well controlled studies are however needed to assess the longer term effects of FCCS on EE.