988 resultados para Enhanced efficiency fertiliser


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BACKGROUND AND AIMS: Fish oil (FO) supplementation prevents the development of obesity and insulin resistance, and upregulate the expression of UCP3 in skeletal muscle in rodents. This may represent indirect evidence that FO promotes fat oxidation and/or alter energy efficiency. The aim of this study was to evaluate whether such effects can be observed in humans. The metabolic effects of FO were assessed during exercise in order to obtain a direct measurement of energy efficiency. METHODS: Eight healthy male volunteers were studied with and without supplementation with 7.2 g/day FO (including 1.1 g/day eicosopentaenoic acid and 0.7 g/day decosahexaenoic acid) during 14 days. Their VO(2 max) was measured on cycle ergometer. Thereafter, energy metabolism (substrate oxidation, energy expenditure and energy efficiency) was assessed during a 30 min cycling exercise at 50% VO(2 max) performed 2 h 30 after a standardized, high carbohydrate breakfast. RESULTS: VO(2 max) was 38.6+/-2.2 after FO and 38.4+/-2.0 (mL x kg(-1) x min(-1)) in control conditions (NS). Basal plasma glucose, insulin and NEFA concentrations, and energy metabolism were similar with FO and in controls. During exercise, the increases in plasma NEFA concentrations, energy expenditure, glucose and lipid oxidation, and the decreases in glycaemia and insulinemia were not altered by FO intake. Energy efficiency was 22.4+/-0.6% after FO vs 21.8+/-0.7% in controls. In order to ascertain that the absence of effects of FO was not due to consumption of a carbohydrate meal immediately before exercise, 4 of the 8 subjects were re-studied in fasting conditions, FO also failed to alter energy efficiency in this subset of studies. CONCLUSION: FO supplementation did not significantly alter energy metabolism and energy efficiency during exercise in healthy humans.

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The objective of this work was to assess the spatial and temporal variability of sugarcane yield efficiency and yield gap in the state of São Paulo, Brazil, throughout 16 growing seasons, considering climate and soil as main effects, and socioeconomic factors as complementary. An empirical model was used to assess potential and attainable yields, using climate data series from 37 weather stations. Soil effects were analyzed using the concept of production environments associated with a soil aptitude map for sugarcane. Crop yield efficiency increased from 0.42 to 0.58 in the analyzed period (1990/1991 to 2005/2006 crop seasons), and yield gap consequently decreased from 58 to 42%. Climatic factors explained 43% of the variability of sugarcane yield efficiency, in the following order of importance: solar radiation, water deficit, maximum air temperature, precipitation, and minimum air temperature. Soil explained 15% of the variability, considering the average of all seasons. There was a change in the correlation pattern of climate and soil with yield efficiency after the 2001/2002 season, probably due to the crop expansion to the west of the state during the subsequent period. Socioeconomic, biotic and crop management factors together explain 42% of sugarcane yield efficiency in the state of São Paulo.

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Contemporary coronary magnetic resonance angiography techniques suffer from signal-to-noise ratio (SNR) constraints. We propose a method to enhance SNR in gradient echo coronary magnetic resonance angiography by using sensitivity encoding (SENSE). While the use of sensitivity encoding to improve SNR seems counterintuitive, it can be exploited by reducing the number of radiofrequency excitations during the acquisition window while lowering the signal readout bandwidth, therefore improving the radiofrequency receive to radiofrequency transmit duty cycle. Under certain conditions, this leads to improved SNR. The use of sensitivity encoding for improved SNR in three-dimensional coronary magnetic resonance angiography is investigated using numerical simulations and an in vitro and an in vivo study. A maximum 55% SNR enhancement for coronary magnetic resonance angiography was found both in vitro and in vivo, which is well consistent with the numerical simulations. This method is most suitable for spoiled gradient echo coronary magnetic resonance angiography in which a high temporal and spatial resolution is required.

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The objective of this work was to evaluate a generalized response function to the atmospheric CO2 concentration [f(CO2)] by the radiation use efficiency (RUE) in rice. Experimental data on RUE at different CO2 concentrations were collected from rice trials performed in several locations around the world. RUE data were then normalized, so that all RUE at current CO2 concentration were equal to 1. The response function was obtained by fitting normalized RUE versus CO2 concentration to a Morgan-Mercer-Flodin (MMF) function, and by using Marquardt's method to estimate the model coefficients. Goodness of fit was measured by the standard deviation of the estimated coefficients, the coefficient of determination (R²), and the root mean square error (RMSE). The f(CO2) describes a nonlinear sigmoidal response of RUE in rice, in function of the atmospheric CO2 concentration, which has an ecophysiological background, and, therefore, renders a robust function that can be easily coupled to rice simulation models, besides covering the range of CO2 emissions for the next generation of climate scenarios for the 21st century.

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The effectiveness of lipid-lowering medication critically depends on the patients' compliance and the efficacy of the prescribed drug. The primary objective of this multicentre study was to compare the efficacy of rosuvastatin with or without access to compliance initiatives, in bringing patients to the Joint European Task Force's (1998) recommended low-density lipoprotein cholesterol (LDL-C) level goal (LDL-C, <3.0 mmol/L) at week 24. Secondary objectives were comparison of the number and percentage of patients achieving European goals (1998, 2003) for LDL-C and other lipid parameters. Patients with primary hypercholesterolaemia and a 10-year coronary heart disease risk of >20% received open label rosuvastatin treatment for 24 weeks with or without access to compliance enhancement tools. The initial daily dosage of 10 mg could be doubled at week 12. Compliance tools included: a) a starter pack for subjects containing a videotape, an educational leaflet, a passport/goal diary and details of the helpline and/or website; b) regular personalised letters to provide message reinforcement; c) a toll-free helpline and a website. The majority of patients (67%) achieved the 1998 European goal for LDL-C at week 24. 31% required an increase in dosage of rosuvastatin to 20 mg at week 12. Compliance enhancement tools did not increase the number of patients achieving either the 1998 or the 2003 European target for plasma lipids. Rosuvastatin was well tolerated during this study. The safety profile was comparable with other drugs of the same class. 63 patients in the 10 mg group and 58 in the 10 mg Plus group discontinued treatment. The main reasons for discontinuation were adverse events (39 patients in the 10 mg group; 35 patients in the 10 mg Plus group) and loss to follow-up (13 patients in the 10 mg group; 9 patients in the 10 mg Plus group). The two most frequently reported adverse events were myalgia (34 patients, 3% respectively) and back pain (23 patients, 2% respectively). The overall rate of temporary or permanent study discontinuation due to adverse events was 9% (n = 101) in patients receiving 10 mg rosuvastatin and 3% (n = 9) in patients titrated up to 20 mg rosuvastatin. Rosuvastatin was effective in lowering LDL-C values in patients with hypercholesterolaemia to the 1998 European target at week 24. However, compliance enhancement tools did not increase the number of patients achieving any European targets for plasma lipids.

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This paper suggests a method for obtaining efficiency bounds in models containing either only infinite-dimensional parameters or both finite- and infinite-dimensional parameters (semiparametric models). The method is based on a theory of random linear functionals applied to the gradient of the log-likelihood functional and is illustrated by computing the lower bound for Cox's regression model

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Laparoscopy is one of the cornerstones in the surgical revolution and transformed outcome and recovery for various surgical procedures. Even if these changes were widely accepted for basic interventions, like appendectomies and cholecystectomies, laparoscopy still remains challenged for more advanced operations in many aspects. Despite these discussion, there is an overwhelming acceptance in the surgical community that laparoscopy did transform the recovery for several abdominal procedures. The importance of improved peri-operative patient management and its influence on outcome started to become a focus of attention 20 years ago and is now increasingly spreading, as shown by the incoming volume of data on this topic. The enhanced recovery after surgery (ERAS) concept incorporates simple measures of general management, and requires multidisciplinary collaboration from hospital staff as well as the patient and the relatives. Several studies have demonstrated a significant decrease in postoperative complication rate, length of hospital stay and reduced overall cost. The key elements of success are fluid restriction, a functioning epidural and preoperative carbohydrate intake. With the expansion of laparoscopic techniques, ERAS increasingly incorporates laparoscopic patients, especially in colorectal surgery. However, the precise impact of laparoscopy on ERAS is still not clearly defined. Increasing evidence suggests that laparoscopy itself is an additional ERAS item that should be considered as routine where feasible in order to obtain the best surgical outcomes.

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The objective of this work was to determine the maintenance requirement and the deposition efficiency of lysine in growing pigs. It was used the incomplete changeover experimental design, with replicates over time. Twelve castrated pigs with average body weight (BW) of 52±2 kg were kept in metabolism crates with a controlled temperature of 22ºC. The diets were formulated to supply 30, 50, 60, and 70% of the expected requirements of standardized lysine, and provided at 2.6 times the energy requirements for maintenance. The trial lasted 24 days and was divided into two periods of 12 days: seven days for animal adaptation to the diet and five days for sample collection. The increasing content of lysine in the diet did not affect dry matter intake of the pigs. The amount of nitrogen excreted was 47% of the nitrogen intake, of which 35% was excreted through feces and 65% through urine. The estimated endogenous losses of lysine were 36.4 mg kg-1 BW0.75. The maintenance requirement of lysine for pigs weighing around 50 kg is 40.4 mg kg-1 BW0.75, and the deposition efficiency of lysine is 90%.

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Animals can compete for resources by displaying various acoustic signals that may differentially affect the outcome of competition. We propose the hypothesis that the most efficient signal to deter opponents should be the one that most honestly reveals motivation to compete. We tested this hypothesis in the barn owl (Tyto alba) in which nestlings produce more calls of longer duration than siblings to compete for priority access to the indivisible prey item their parents will deliver next. Because nestlings increase call rate to a larger extent than call duration when they become hungrier, call rate would signal more accurately hunger level. This leads us to propose three predictions. First, a high number of calls should be more efficient in deterring siblings to compete than long calls. Second, the rate at which an individual calls should be more sensitive to variation in the intensity of the sibling vocal competition than the duration of its calls. Third, call rate should influence competitors' vocalization for a longer period of time than call duration. To test these three predictions we performed playback experiments by broadcasting to singleton nestlings calls of varying durations and at different rates. According to the first prediction, singleton nestlings became less vocal to a larger extent when we broadcasted more calls compared to longer calls. In line with the second prediction, nestlings reduced vocalization rate to a larger extent than call duration when we broadcasted more or longer calls. Finally, call rate had a longer influence on opponent's vocal behavior than call duration. Young animals thus actively and differentially use multiple signaling components to compete with their siblings over parental resources.

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A particular property of the matched desiredimpulse response receiver is introduced in this paper, namely,the fact that full exploitation of the diversity is obtained withmultiple beamformers when the channel is spatially and timelydispersive. This particularity makes the receiver specially suitablefor mobile and underwater communications. The new structureprovides better performance than conventional and weightedVRAKE receivers, and a diversity gain with no needs of additionalradio frequency equipment. The baseband hardware neededfor this new receiver may be obtained through reconfigurabilityof the RAKE architectures available at the base station. Theproposed receiver is tested through simulations assuming UTRAfrequency-division-duplexing mode.

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The objective of this work was to isolate and characterize rhizobia from nodules of Centrolobium paraense and to evaluate their symbiotic efficiency. Soil samples collected from four sites of the Roraima Cerrado, Brazil, were used to cultivate C. paraense in order to obtain nodules. Isolates (178) were obtained from 334 nodules after cultivation on medium 79. Twenty-five isolates belonging to six morphological groups were authenticated using Vigna unguiculata and they were characterized by 16S rRNA. Isolates identified as Bradyrhizobium were further characterized using rpoB gene sequencing. A greenhouse experiment was carried out with C. paraense to test the 18 authenticated isolates. Approximately 90% of the isolates grew slowly in medium 79. The 16S rRNA analysis showed that 14 authenticated isolates belong to the genus Bradyrhizobium, and rpoB indicated they constitute different groups compared to previously described species. Only four of the 11 fast-growing isolates nodulated V. unguiculata, two of which belong to Rhizobium, and two to Pleomorphomonas, which was not previously reported as a nodulating genus. The Bradyrhizobium isolates ERR 326, ERR 399, and ERR 435 had the highest symbiotic efficiency on C. paraense and showed a contribution similar to the nitrogen treatment. Centrolobium paraense is able to nodulate with different rhizobium species, some of which have not yet been described.

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This paper proposes a managerial control tool that integrates risk in efficiency scores. Building on existing efficiency specifications, our proposal reflects the real banking technology and accurately models the relationship between desirable and undesirable outputs. Specifically, the undesirable output is defined as non-performing loans to capture credit risk, and is linked only to the relevant dimension of the output set. We empirically illustrate how our efficiency measure functions for managerial control purposes. The application considers a unique dataset of Costa Rican banks during 1998-2012. Efficiency scores? implications are mostly discussed at bank-level, and their interpretations are enhanced by using accounting ratios. We also show the usefulness of our tool for corporate governance by examining performance changes around executive turnover. Results confirm that appointing CEOs from outside the bank significantly improves performance, thus suggesting the potential benefits of new organisational practices.

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The priming agent β-aminobutyric acid (BABA) is known to enhance Arabidopsis resistance to the bacterial pathogen Pseudomonas syringae pv. tomato (Pst) DC3000 by potentiating salicylic acid (SA) defence signalling, notably PR1 expression. The molecular mechanisms underlying this phenomenon remain unknown. A genome-wide microarray analysis of BABA priming during Pst DC3000 infection revealed direct and primed up-regulation of genes that are responsive to SA, the SA analogue benzothiadiazole and pathogens. In addition, BABA was found to inhibit the Arabidopsis response to the bacterial effector coronatine (COR). COR is known to promote bacterial virulence by inducing the jasmonic acid (JA) response to antagonize SA signalling activation. BABA specifically repressed the JA response induced by COR without affecting other plant JA responses. This repression was largely SA-independent, suggesting that it is not caused by negative cross-talk between SA and JA signalling cascades. Treatment with relatively high concentrations of purified COR counteracted BABA inhibition. Under these conditions, BABA failed to protect Arabidopsis against Pst DC3000. BABA did not induce priming and resistance in plants inoculated with a COR-deficient strain of Pst DC3000 or in the COR-insensitive mutant coi1-16. In addition, BABA blocked the COR-dependent re-opening of stomata during Pst DC3000 infection. Our data suggest that BABA primes for enhanced resistance to Pst DC3000 by interfering with the bacterial suppression of Arabidopsis SA-dependent defences. This study also suggests the existence of a signalling node that distinguishes COR from other JA responses.

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BACKGROUND: Takayasu arteritis (TA) is a rare form of chronic inflammatory granulomatous arteritis of the aorta and its major branches. Late gadolinium enhancement (LGE) with magnetic resonance imaging (MRI) has demonstrated its value for the detection of vessel wall alterations in TA. The aim of this study was to assess LGE of the coronary artery wall in patients with TA compared to patients with stable CAD. METHODS: We enrolled 9 patients (8 female, average age 46±13 years) with proven TA. In the CAD group 9 patients participated (8 male, average age 65±10 years). Studies were performed on a commercial 3T whole-body MR imaging system (Achieva; Philips, Best, The Netherlands) using a 3D inversion prepared navigator gated spoiled gradient-echo sequence, which was repeated 34-45 minutes after low-dose gadolinium administration. RESULTS: No coronary vessel wall enhancement was observed prior to contrast in either group. Post contrast, coronary LGE on IR scans was detected in 28 of 50 segments (56%) seen on T2-Prep scans in TA and in 25 of 57 segments (44%) in CAD patients. LGE quantitative assessment of coronary artery vessel wall CNR post contrast revealed no significant differences between the two groups (CNR in TA: 6.0±2.4 and 7.3±2.5 in CAD; p = 0.474). CONCLUSION: Our findings suggest that LGE of the coronary artery wall seems to be common in patients with TA and similarly pronounced as in CAD patients. The observed coronary LGE seems to be rather unspecific, and differentiation between coronary vessel wall fibrosis and inflammation still remains unclear.