908 resultados para exhaust hood


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Generalist predators are capable of consuming different types of prey, and as each prey may have distinct nutritional values, each may have a distinct impact on the biology of the predator. Therefore, the aim of this study was to determine how the consumption of different prey influences certain biological characteristics and the predatory capacity of Orius insidiosus (Say). The investigation was performed in climatic chamber at 25 ±1 ºC, RH 70 ± 10% and fotophase 12. Eggs of Anagasta kuehniella (Zeller), adults of Caliothrips phaseoli (Hood) and nymphs of Aphis gossypii Glover were used as prey and were provided daily ad libitum for all the mobile stages of the predator. The results showed that biological parameters of O. insidiosus are affected differently depending on the type of prey ingested. The development time of the nymphal stage was 13.1, 11.23 and 10.25 days for O. insidiosus feeding on eggs of A. kuehniella, nymphs of A. gossypii and adults of C. phaseoli, respectively. Longevity was five times larger for adults fed on eggs of A. kuehniella (56.25 days) compared to that of adults that preyed on nymphs of A. gossypii (11.44 days), and four times larger when the prey were adults of C. phaseoli (13.58 days). The consumption of eggs of A. kuehniella by predator females resulted in a shorter pre-oviposition period (3.2 days) and a longer oviposition period (44.4 days) when compared to the consumption of other types of prey. In addition, fecundity was increased with the consumption of eggs of A. kuehniella (195.25 eggs laid / female) when compared to feeding on the other prey, C. phaseoli (70.00 eggs laid / female) or A. gossypii (22.50 eggs laid / female). However, the consumption of aphids was larger (148.28 nymphs/ nymphal stage) than that of thrips (74.10 thrips / nymphal stage) or eggs of A. kuehniella (37.03 eggs /nymphal stage) for all of the nymphal stages of the predator. The results indicate that the eggs of A. kuehniella are the type of prey best suited for rearing this predator insect under laboratory conditions. Also fecundity was better with this prey even though the predator consumed during its nymphal stage a lesser quantity of eggs compared to the other prey.

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The aim of this single-blind, placebo-controlled study was to investigate the effects of the new beta-adrenergic compound Ro 40-2148 on resting energy expenditure (REE) at rest and after an oral glucose load in non-diabetic obese women before and after two weeks of treatment. After one week of placebo administration and after an overnight fast and one hour rest, REE and glucose and lipid oxidation rates were measured by indirect calorimetry (hood system) before and for 6 h after a single dose of placebo solution. A 75 g oral glucose tolerance test (OGTT) was performed during this period starting 90 min after the placebo administration. During the following two weeks, using a randomization design, six patients received Ro 40-2148 at a dose of 400 mg diluted in 100 ml water twice a day (i.e. 800 mg per day), while six others continued with the placebo administration. The same tests and measurements were repeated after two weeks, except for the treatment group which received the drug instead of the placebo. The 14-day period of drug administration did not increase REE measured in post-absorptive conditions. Similarly, there was no acute effect on REE of a 400 mg dose of Ro 40-2148. In contrast, glucose-induced thermogenesis was significantly increased after two weeks in the treatment group (means +/- s.e.m.: 3.7 +/- 1.3%, P = 0.047), while no change was observed in the placebo group (-0.8 +/- 0.7%, not significant). Since there was no significant change in the respiratory quotient, the increase in energy expenditure observed in the treatment group was due to stimulation of both lipid and glucose oxidation. The drug induced no variations in heart rate, blood pressure, axillary temperature or in plasma glucose, insulin and free fatty acid levels. In conclusion, this study shows that Ro 40-2148 activates glucose-induced thermogenesis in obese non-diabetic patients.

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Species of thrips (Insecta, Thysanoptera) in two strawberry production systems in Rio Grande do Sul, Brazil. Thrips are tiny insects responsible for the reduction of strawberry fruit quality. The work aimed to record and quantify the thysanopterofauna present in two strawberry production systems, low tunnel and semi-hydroponic. Leaves, flowers and fruits were collected weekly, from July 2005 to December 2006 in Caxias do Sul and Bom Princípio municipalities, RS. A total of 664 individuals were collected, representing two families, four genus and 10 species: Frankliniella occidentalis (Pergande, 1895), F. schultzei (Trybom, 1910), F. rodeos Moulton, 1933, F. simplex (Priesner, 1924), F. williamsi (Hood, 1915), F. gemina (Bagnall, 1919), Frankliniella sp., Thrips tabaci (Lindeman, 1888), Thrips tabaci (Lindeman, 1888), Caliothrips fasciatus (Pergande 1895) from Thripidae and Heterothrips sp. from Heterothripidae. Frankliniella occidentalis represented 89.7% of the samples with 95.8% of the species collected in flowers, 3.9% in fruits and 0.8% in leaves. The results show that flowers are the most important food resource for these insects on strawberry plants. Frankliniella rodeos, F. simplex, F. williamsi, C. fasciatus, and Heterothrips sp. are new records on strawberry for Brazil.

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The thermogenic response induced by ethanol ingestion in humans has not been extensively studied. This study was designed to determine the thermic effect of ethanol added to a normal diet in healthy nonalcoholic subjects, using indirect calorimetry measurements over a 24-h period in a respiration chamber. The thermic effect of ethanol was also measured when ethanol was ingested in the fasting state, using a ventilated hood system during a 5-h period. Six subjects ingested 95.6 +/- 1.8 (SE) g ethanol in 1 day partitioned over three meals; there was a 5.5 +/- 1.2% increase in 24-h energy expenditure compared with a control day in which all conditions were identical except that no ethanol was consumed. The calculated ethanol-induced thermogenesis (EIT) was 22.5 +/- 4.7% of the ethanol energy ingested. Ingestion of 31.9 +/- 0.6 g ethanol in the fasting state led to a 7.4 +/- 0.6% increase in energy expenditure over baseline values, and the calculated EIT was 17.1 +/- 2.2%. It is concluded that in healthy nonalcoholic adults ethanol elicits a thermogenic response equal to approximately 20% of the ethanol energy. Thus the concept of the apparently inefficient utilization of ethanol energy is supported by these results which show that only approximately 80% of the ethanol energy is used as metabolizable energy for biochemical processes in healthy nonalcoholic moderate ethanol consumers.

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The magnitude of variability in resting energy expenditure (REE) during the day was assessed in nine healthy young subjects under two nutritional conditions: 1) mixed nutrient (53% carbohydrate, 30% fat, 17% protein) enteral feeding at an energy level corresponding to 1.44 REE; and 2) enteral fasting, with only water allowed. In each subject, six 30-min measurements of REE were performed using indirect calorimetry (hood system) at 90-min intervals from 9 AM to 5 PM. The mean REE and respiratory quotient were significantly (p less than .01) greater during feeding than during fasting (1.08 +/- 0.07 [SEM] vs. 1.00 +/- 0.06 kcal/min and 0.874 +/- 0.007 vs. 0.829 +/- 0.008 kcal/min, respectively). Mean postprandial thermogenesis was 4.9 +/- 0.4% of metabolizable energy administered. The intraindividual variability of REE throughout the day, expressed as the coefficient of variation, ranged from 0.7% to 2.0% in the fasting condition and from 1.2% to 4.1% in the feeding condition. There was no significant difference between the REE measured in the morning and that determined in the afternoon.

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Road transport emissions are a major contributor to ambient particulate matter concentrations and have been associated with adverse health effects. Therefore, these emissions are targeted through increasingly stringent European emission standards. These policies succeed in reducing exhaust emissions, but do not address "nonexhaust" emissions from brake wear, tire wear, road wear, and suspension in air of road dust. Is this a problem? To what extent do nonexhaust emissions contribute to ambient concentrations of PM10 or PM2.5? In the near future, wear emissions may dominate the remaining traffic-related PM10 emissions in Europe, mostly due to the steep decrease in PM exhaust emissions. This underlines the need to determine the relevance of the wear emissions as a contribution to the existing ambient PM concentrations, and the need to assess the health risks related to wear particles, which has not yet received much attention. During a workshop in 2011, available knowledge was reported and evaluated so as to draw conclusions on the relevance of traffic-related wear emissions for air quality policy development. On the basis of available evidence, which is briefly presented in this paper, it was concluded that nonexhaust emissions and in particular suspension in air of road dust are major contributors to exceedances at street locations of the PM10 air quality standards in various European cities. Furthermore, wear-related PM emissions that contain high concentrations of metals may (despite their limited contribution to the mass of nonexhaust emissions) cause significant health risks for the population, especially those living near intensely trafficked locations. To quantify the existing health risks, targeted research is required on wear emissions, their dispersion in urban areas, population exposure, and its effects on health. Such information will be crucial for environmental policymakers as an input for discussions on the need to develop control strategies.

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We are interested in the development, implementation and testing of an orthotropic model for cardiac contraction based on an active strain decomposition. Our model addresses the coupling of a transversely isotropic mechanical description at the cell level, with an orthotropic constitutive law for incompressible tissue at the macroscopic level. The main differences with the active stress model are addressed in detail, and a finite element discretization using Taylor-Hood and MINI elements is proposed and illustrated with numerical examples.

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In "Reading, Translating, Rewriting: Angela Carter's Translational Poetics", author Martine Hennard Dutheil de la Rochère delves into Carter's The Fairy Tales of Charles Perrault (1977) to illustrate that this translation project had a significant impact on Carter's own writing practice. Hennard combines close analyses of both texts with an attention to Carter's active role in the translation and composition process to explore this previously unstudied aspect of Carter's work. She further uncovers the role of female fairy-tale writers and folktales associated with the Grimms' Kinder- und Hausmärchen in the rewriting process, unlocking new doors to The Bloody Chamber. Hennard begins by considering the editorial evolution of The Fairy Tales of Charles Perrault from 1977 to the present day, as Perrault's tales have been rediscovered and repurposed. In the chapters that follow, she examines specific linkages between Carter's Perrault translation and The Bloody Chamber, including targeted analysis of the stories of Red Riding Hood, Bluebeard, Puss-in-Boots, Beauty and the Beast, Sleeping Beauty, and Cinderella. Hennard demonstrates how, even before The Bloody Chamber, Carter intervened in the fairy-tale debate of the late 1970s by reclaiming Perrault for feminist readers when she discovered that the morals of his worldly tales lent themselves to her own materialist and feminist goals. Hennard argues that The Bloody Chamber can therefore be seen as the continuation of and counterpoint to The Fairy Tales of Charles Perrault, as it explores the potential of the familiar stories for alternative retellings. While the critical consensus reads into Carter an imperative to subvert classic fairy tales, the book shows that Carter valued in Perrault a practical educator as well as a proto-folklorist and went on to respond to more hidden aspects of his texts in her rewritings. Reading, Translating, Rewriting is informative reading for students and teachers of fairy-tale studies and translation studies.

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To explore the changes in resting energy expenditure (REE) and whole body protein turnover induced by malaria, 23 children aged 6 to 14 y (23.9 +/- 1.0 kg, 1.3 +/- 0.02 m) were studied on three separate days after treatment (d 1, d 2, and 15 d later). REE was assessed by indirect calorimetry (hood), whereas whole body protein turnover was estimated using a single dose of [15N]glycine administered p.o. by measuring the isotopic enrichment of [15N]ammonia in urine over 12 h. Within the first 3.5 h after treatment, the body temperature dropped from 39.8 +/- 0.1 to 37.8 +/- 0.1 degrees C (p < 0.0001), and REE followed the same pattern, decreasing rapidly from 223 +/- 6 to 187 +/- 4 kJ/kg/d (p < 0.0001). Whole body protein synthesis and breakdown were significantly higher during the 1st day (5.65 +/- 0.38 and 6.21 +/- 0.43 g/kg/d, respectively) than at d 15 (2.95 +/- 0.17 and 2.77 +/- 0.2 g/kg/d). It is concluded that Gambian children suffering from an acute episode of malaria have an increased REE averaging 37% of the control value (d 15) and that this was associated with a substantial increase (by a factor of 2) in whole body protein turnover. A rapid normalization of the hypermetabolism and protein hypercatabolism states after treatment was observed.

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Amana Farms is using an anaerobic digestion, which is a two-stage digester that converts manure and other organic wastes into three valuable by-products: 1) Biogas – to fuel an engine/generator set to create electricity; 2) Biosolids - used as a livestock bedding material or as a soil amendment; 3) Liquid stream - will be applied as a low-odor fertilizer to growing crops. (see Business Plan appendix H) The methane biogas will be collected from the two stages of the anaerobic digestion vessel and used for fuel in the combined heat and power engine/generator sets. The engine/generator sets are natural gasfueled reciprocating engines modified to burn biogas. The electricity produced by the engine/generator sets will be used to offset on-farm power consumption and the excess power will be sold directly to Amana Society Service Company as a source of green power. The waste heat, in the form of hot water, will be collected from both the engine jacket liquid cooling system and from the engine exhaust (air) system. Approximately 30 to 60% of this waste heat will be used to heat the digester. The remaining waste heat will be used to heat other farm buildings and may provide heat for future use for drying corn or biosolids. The digester effluent will be pumped from the effluent pit at the end of the anaerobic digestion vessel to a manure solids separator. The mechanical manure separator will separate the effluent digested waste stream into solid and liquid fractions. The solids will be dewatered to approximately a 35% solid material. Some of the separated solids will be used by the farm for a livestock bedding replacement. The remaining separated solids may be sold to other farms for livestock bedding purposes or sold to after-markets, such as nurseries and composters for soil amendment material. The liquid from the manure separator, now with the majority of the large solids removed, will be pumped into the farm’s storage lagoon. A significant advantage of the effluent from the anaerobic digestion treatment process is that the viscosity of the effluent is such that the liquid effluent can now be pumped through an irrigation nozzle for field spreading.

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In a previous study, we demonstrated that the new beta-adrenoceptor agonist Ro 16-8714 possesses thermogenic property in normal male volunteers. The aim of the present study was to compare the metabolic response of lean vs obese individuals to a similar dose of this compound. Following an overnight fast, Ro 16-8714 (0.17 mg/kg fat free mass) or a placebo was given per os to six normal-weight subjects and to six moderately obese subjects. The rate of energy expenditure (EE) and the substrate utilization were determined by indirect calorimetry (hood system) before and for 6 h following the drug administration. Heart rate and blood pressure as well as plasma glucose, insulin and free fatty acid (FFA) concentrations were also measured at regular intervals throughout the study. The increment relative to base-line (mean +/- s.e.m.) in EE was similar in the two groups and averaged 4.0 +/- 1.4 per cent and 12.2 +/- 1.4 per cent with placebo and with Ro 16-8714 respectively in lean subjects, whereas the values reached 3.5 +/- 1.2 per cent and 14.4 +/- 2.0 per cent in obese subjects. Heart rate, systolic blood pressure, insulin and FFA were increased without any significant difference between the two groups. This study shows that Ro 16-8714 is a potent thermogenic agent both in normal and obese subjects.

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The present study was designed to explore the thermogenic effect of thyroid hormone administration and the resulting changes in nitrogen homeostasis. Normal male volunteers (n = 7) received thyroxin during 6 weeks. The first 3-week period served to suppress endogenous thyroid secretion (180 micrograms T4/day). This dose was doubled for the next 3 weeks. Sleeping energy expenditure (respiratory chamber) and BMR (hood) were measured by indirect calorimetry, under standardized conditions. Sleeping heart rate was continuously recorded and urine was collected during this 12-hour period to assess nitrogen excretion. The changes in energy expenditure, heart rate and nitrogen balance were then related to the excess thyroxin administered. After 3 weeks of treatment, serum TSH level fell to 0.15 mU/L, indicating an almost complete inhibition of the pituitary-thyroid axis. During this phase of treatment there was an increase in sleeping EE and sleeping heart rate, which increased further by doubling the T4 dose (delta EE: +8.5 +/- 2.3%, delta heart rate +16.1 +/- 2.2%). The T4 dose, which is currently used as a substitutive dose, lead to a borderline hyperthyroid state, with an increase in EE and heart rate. Exogenous T4 administration provoked a significant increase in urinary nitrogen excretion averaging 40%. It is concluded that T4 provokes an important stimulation of EE, which is mostly mediated by an excess protein oxidation.

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In six young obese women (mean weight 85 +/- 3 kg) with a childhood history of obesity, and in six young nonobese women (mean weight 55 +/- 2 kg), the energy expenditure was measured during 24 h in a respiratory chamber with a maintenance energy intake. The next day, the thermogenic response to a mixed meal was investigated by using an open circuit indirect calorimetry hood system. In addition, five of the same obese women were similarly studied after a mean weight loss of 12.1 kg (14% of initial body weight) consecutive to an 11-wk hypocaloric diet (protein-supplemented modified fast). Expressed in absolute terms, the total 24 h and basal energy expenditures were found to be significantly greater in the obese (2208 +/- 105 and 1661 +/- 56 kcal/24 h, respectively) than in the controls (1746 +/- 61 and 1230 +/- 40 kcal/24 h, respectively). After weight loss, both the total 24-h and the basal energy expenditures were significantly reduced (2009 +/- 99 kcal/24 h and 1423 +/- 43 kcal/24 h respectively), but both values were still greater than that of the control subjects. The thermogenic response to the mixed meal (a liquid diet containing 17, 54, and 29% as protein, carbohydrate, and lipid calories, respectively, and an energy level determined to cover 60% of the basal energy expenditure computed for 24 h) was found to be significantly reduced in the obese as compared to controls (ie, 7.6 +/- 0.4% versus 9.5 +/- 0.4% of the energy content of the load, respectively, p less than 0.025). After weight loss, the postprandial thermogenesis of the obese was still markedly reduced (ie, 6.2 +/- 0.8%). Both before and after weight loss, the relative increase in diurnal urinary norepinephrine excretion was found to be lower in the obese than in controls, when compared to the nocturnal values. These results show that the greater 24 h energy expenditure of obese women is entirely due to their higher basal metabolic rate. The lower thermogenic response to the meal in the obese supports the concept of a thermogenic defect which can favor energy gain; furthermore, the unchanged response after weight loss in the obese suggests that the thermogenic defect may be a cause rather than a consequence of obesity.

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Mating systems, that is, whether organisms give rise to progeny by selfing, inbreeding or outcrossing, strongly affect important ecological and evolutionary processes. Large variations in mating systems exist in fungi, allowing the study of their origin and consequences. In fungi, sexual incompatibility is determined by molecular recognition mechanisms, controlled by a single mating-type locus in most unifactorial fungi. In Basidiomycete fungi, however, which include rusts, smuts and mushrooms, a system has evolved in which incompatibility is controlled by two unlinked loci. This bifactorial system probably evolved from a unifactorial system. Multiple independent transitions back to a unifactorial system occurred. It is still unclear what force drove evolution and maintenance of these contrasting inheritance patterns that determine mating compatibility. Here, we give an overview of the evolutionary factors that might have driven the evolution of bifactoriality from a unifactorial system and the transitions back to unifactoriality. Bifactoriality most likely evolved for selfing avoidance. Subsequently, multiallelism at mating-type loci evolved through negative frequency-dependent selection by increasing the chance to find a compatible mate. Unifactoriality then evolved back in some species, possibly because either selfing was favoured or for increasing the chance to find a compatible mate in species with few alleles. Owing to the existence of closely related unifactorial and bifactorial species and the increasing knowledge of the genetic systems of the different mechanisms, Basidiomycetes provide an excellent model for studying the different forces that shape breeding systems.