939 resultados para short-term exposure


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Methods to measure enteric methane (CH4) emissions from individual ruminants in their production environment are required to validate emission inventories and verify mitigation claims. Estimates of daily methane production (DMP) based on consolidated short-term emission measurements are developing, but method verification is required. Two cattle experiments were undertaken to test the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate did not differ from DMP measured in respiration chambers (RC). Short-term emission rates were obtained from a GreenFeed Emissions Monitoring (GEM) unit, which measured emission rate while cattle consumed a dispensed supplement. In experiment 1 (Expt. 1), four non-lactating cattle (LW=518 kg) were adapted for 18 days then measured for six consecutive periods. Each period consisted of 2 days of ad libitum intake and GEM emission measurement followed by 1 day in the RC. A prototype GEM unit releasing water as an attractant (GEM water) was also evaluated in Expt. 1. Experiment 2 (Expt. 2) was a larger study based on similar design with 10 cattle (LW=365 kg), adapted for 21 days and GEM measurement was extended to 3 days in each of the six periods. In Expt. 1, there was no difference in DMP estimated by the GEM unit relative to the RC (209.7 v. 215.1 g CH4/day) and no difference between these methods in methane yield (MY, 22.7 v. 23.7 g CH4/kg of dry matter intake, DMI). In Expt. 2, the correlation between GEM and RC measures of DMP and MY were assessed using 95% confidence intervals, with no difference in DMP or MY between methods and high correlations between GEM and RC measures for DMP (r=0.85; 215 v. 198 g CH4/day SEM=3.0) and for MY (r=0.60; 23.8 v. 22.1 g CH4/kg DMI SEM=0.42). When data from both experiments was combined neither DMP nor MY differed between GEM- and RC-based measures (P>0.05). GEM water-based estimates of DMP and MY were lower than RC and GEM (P<0.05). Cattle accessed the GEM water unit with similar frequency to the GEM unit (2.8 v. 3.5 times/day, respectively) but eructation frequency was reduced from 1.31 times/min (GEM) to once every 2.6 min (GEM water). These studies confirm the hypothesis that DMP estimated by averaging multiple short-term breath measures of methane emission rate using GEM does not differ from measures of DMP obtained from RCs. Further, combining many short-term measures of methane production rate during supplement consumption provides an estimate of DMP, which can be usefully applied in estimating MY.

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A combined Short-Term Learning (STL) and Long-Term Learning (LTL) approach to solving mobile robot navigation problems is presented and tested in both real and simulated environments. The LTL consists of rapid simulations that use a Genetic Algorithm to derive diverse sets of behaviours. These sets are then transferred to an idiotypic Artificial Immune System (AIS), which forms the STL phase, and the system is said to be seeded. The combined LTL-STL approach is compared with using STL only, and with using a handdesigned controller. In addition, the STL phase is tested when the idiotypic mechanism is turned off. The results provide substantial evidence that the best option is the seeded idiotypic system, i.e. the architecture that merges LTL with an idiotypic AIS for the STL. They also show that structurally different environments can be used for the two phases without compromising transferability.

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Background: Umbilical arterial blood gas (UABG) analysis is more objective than other methods for predicting neonatal outcome. Acidemic neonates may be at risk for unfavorable outcome after birth, but all neonates with abnormal arterial blood gas (ABG) analysis do not always have poor outcome. Objectives: This study was carried out to determine the short term outcome of the neonates born with an abnormal ABG. Patients and Methods: In a cohort prospective study 120 high risk mother-neonate pairs were enrolled and UABG was taken immediately after birth. All neonates with an umbilical cord pH less than 7.2 were considered as case group and more than 7.2 as controls. Outcomes like need to resuscitation, admission to newborn services and/or NICU), seizure occurrence, hypoxic ischemic encephalopathy (HIE), delayed initiation of oral feeding and length of hospital stay were recorded and compared between the two groups. P value less than 0.05 was considered as being significant. Results: Comparison of short term outcomes between normal and abnormal ABG groups were as the fallowing: need for advanced resuscitation 4 vs. 0 (P = 0.001), NICU admission 16 vs. 4 (P = 0.001), convulsion 2 vs. 0 (P = 0.496), HIE 17 vs. 4 (P = 0.002), delay to start oral feeding 16 vs. 4 (P = 0.001), mean hospital stay 4 vs. 3 days (P = 0.001). None of the neonates died in study groups. Conclusions: An umbilical cord PH less than 7.2 immediately after birth can be used as a prognostic factor for unfavorable short term outcome in newborns.

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Introduction: Truncus arteriosus with intact ventricular septum is a rare and unique variant of persistent truncus arteriosus (PTA) which usually presents with central cyanosis and congestive heart failure in neonate and early infancy. Associated cardiac and non-cardiac anomalies may affect morbidity and mortality of these patients. Case Presentation: We describe clinical presentation, echocardiography and angiographic features of a 7-month old boy with PTA and intact ventricular septum who underwent surgical repair of the anomaly at our institution. Operative findings, surgical procedure and short-term outcome are reported. Conclusions: While our patient had systemic pulmonary arterial pressure at the time of complete surgical repair, it was improved after surgery.

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Background: Transcatheter closure of atrial septal defects (ASD) has been accepted world-wide as an alternative to surgical closure with excellent results. This interventional, non-surgical technique plays an important role in the treatment of ASD mostly in the developing world where resources are limited. Objectives: To report the outcomes and short term follow-up of transcatheter closure of ASD over a 12-year period at our institution with limited resources. Patients and Methods: This retrospective study included all patients with the diagnosis of secundum ASD and significant shunting (Qp/Qs > 1.5:1) as well as dilated right atrium and right ventricle who had transcatheter closure at Integrated Cardiovascular Center (PJT), Dr. Cipto Mangunkusumo Hospital between October 2002 and October 2014. One hundred fifty-two patients enrolled in this study were candidates for device closure. Right and left heart cardiac catheterization was performed before the procedure. All patients underwent physical examination, ECG, chest X-ray and transthoracal echocardiography (TTE) prior to device implantation. Results: A total of 152 patients with significant ASD underwent device implantation. Subjects’ age ranged from 0.63 to 69.6 years, with median 9.36 years and mean 16.30 years. They consisted of 33 (21.7%) males and 119 (78.3%) females, with mean body weight of 29.9 kg (range 8 to 75; SD 18.2). The device was successfully implanted in 150 patients where the majority of cases received the Amplatzer septal occluder (147/150; 98%) and the others received the Heart Lifetech ASD occluder (3/150, 2%), whereas two other cases were not suitable for device closure and we decided for surgical closure. The mean ASD size was 19.75 (range 14 - 25) mm. During the procedure, 5 (4.9%) patients had bradycardia and 3 (2.9%) patients had supraventricular tachycardia (SVT), all of which resolved. Conclusions: In our center with limited facilities and manpower, transcatheter closure of atrial septal defect was effective and safe as an alternative treatment to surgery. The outcome and short-term follow-up revealed excellent results, but long-term follow-up is needed.

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BACKGROUND: Free school breakfast programmes (SBPs) exist in a number of high-income countries, but their effects on educational outcomes have rarely been evaluated in randomised controlled trials.

METHODS: A 1-year stepped-wedge, cluster randomised controlled trial was undertaken in 14 New Zealand schools in low socioeconomic resource areas. Participants were 424 children, mean age 9±2 years, 53% female. The intervention was a free daily SBP. The primary outcome was children's school attendance. Secondary outcomes were academic achievement, self-reported grades, sense of belonging at school, behaviour, short-term hunger, breakfast habits and food security.

RESULTS: There was no statistically significant effect of the breakfast programme on children's school attendance. The odds of children achieving an attendance rate <95% was 0.76 (95% CI 0.56 to 1.02) during the intervention phase and 0.93 (95% CI 0.67 to 1.31) during the control phase, giving an OR of 0.81 (95% CI 0.59 to 1.11), p=0.19. There was a significant decrease in children's self-reported short-term hunger during the intervention phase compared with the control phase, demonstrated by an increase of 8.6 units on the Freddy satiety scale (95% CI 3.4 to 13.7, p=0.001). There were no effects of the intervention on any other outcome.

CONCLUSIONS: A free SBP did not have a significant effect on children's school attendance or academic achievement but had significant positive effects on children's short-term satiety ratings. More frequent programme attendance may be required to influence school attendance and academic achievement.

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Accurate and timely traffic flow prediction is crucial to proactive traffic management and control in data-driven intelligent transportation systems (D2ITS), which has attracted great research interest in the last few years. In this paper, we propose a Spatial-Temporal Weighted K-Nearest Neighbor model, named STW-KNN, in a general MapReduce framework of distributed modeling on a Hadoop platform, to enhance the accuracy and efficiency of short-term traffic flow forecasting. More specifically, STW-KNN considers the spatial-temporal correlation and weight of traffic flow with trend adjustment features, to optimize the search mechanisms containing state vector, proximity measure, prediction function, and K selection. urthermore, STW-KNN is implemented on a widely adopted Hadoop distributed computing platform with the MapReduce parallel processing paradigm, for parallel prediction of traffic flow in real time. inally, with extensive experiments on real-world big taxi trajectory data, STW-KNN is compared with the state-of-the-art prediction models including conventional K-Nearest Neighbor (KNN), Artificial Neural Networks (ANNs), Naïve Bayes (NB), Random orest (R), and C4.. The results demonstrate that the proposed model is superior to existing models on accuracy by decreasing the mean absolute percentage error (MAPE) value more than 11.9% only in time domain and even achieves 89.71% accuracy improvement with the MAPEs of between 4% and 6.% in both space and time domains, and also significantly improves the efficiency and scalability of short-term traffic flow forecasting over existing approaches.

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The ten year obesity prevention framework, A Fitter Future for All 2012-2022, was launched in 9th March 2012. It takes a cross-sectoral, cross-departmental approach to preventing and addressing obesity through encouraging and supporting people to eat healthily and participate in physical activity. Initial short-term outcomes where developed for the period 2012-2015 – to fit alongside the then Programme for Government. This document provides a final update and a summary report of all the activities undertaken during this period.

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PURPOSE: To assess the relationship between short-term and long-term changes in power at different corneal locations relative to the change in central corneal power and the 2-year change in axial elongation relative to baseline in children fitted with orthokeratology contact lenses (OK). METHODS: Thirty-one white European subjects 6 to 12 years of age and with myopia −0.75 to −4.00 DS and astigmatism ≤1.00 DC were fitted with OK. Differences in refractive power 3 and 24 months post-OK in comparison with baseline and relative to the change in central corneal power were determined from corneal topography data in eight different corneal regions (i.e., N[nasal]1, N2, T[temporal]1, T2, I[inferior]1, I2, S[superior]1, S2), and correlated with OK-induced axial length changes at two years relative to baseline. RESULTS: After 2 years of OK lens wear, axial length increased by 0.48±0.18 mm (P0.05). CONCLUSION: The reduction in central corneal power and relative increase in paracentral and pericentral power induced by OK over 2 years were not significantly correlated with concurrent changes in axial length of white European children.

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Secular trends in height and weight are reasonably well documented in Europe. Corresponding observations for skeletal maturation are lacking. Aim: To assess secular trends in height, body mass and skeletal maturity of Portuguese children and adolescents and to provide updated reference values for skeletal maturity scores (SMSs). Subjects and methods: Data for 2856 children and adolescents of 4–17 years, 1412 boys and 1444 girls, from The ‘Madeira Growth Study’ (MGS; 1996–1998) and from the‘Healthy Growth of Madeira Children Study’ (CRES; 2006) were used. Height and body mass were measured. Skeletal maturity was assessed with the Tanner-Whitehouse 2 and 3 methods. Results: Children from CRES were taller and heavier than peers from MGS. Differences in height reached 5.8cm in boys and 5.5cm in girls. RUS SMSs did not differ consistently between surveys boys, while higher RUS scores were observed in CRES girls. Adult RUS SMSs for MGS and CRES combined were attained at 15.8 years in boys and 14.8 years in girls. Corresponding ages for adult Carpal SMSs were 14.4 and 14.0, respectively. Conclusion: The short-term trends for height and mass were not entirely consistent with the trends in RUS and Carpal SMSs and SAs.

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ABSTRACT: Short-term debt and credit ratings have benefits for financial reporting quality that may be associated with lower audit fees. Using U.S. data for 2003 through 2006, we find that short-term debt is negatively related to audit fees for firms rated by Standard & Poor’s, consistent with more monitoring and better governance mechanisms in firms with higher short-term debt. Credit ratings quality is negatively related to audit fees, consistent with ratings quality reflecting a firm’s liquidity risk, governance mechanisms, and monitoring from rating agencies. We also find that the negative relation between short-term debt and audit fees is stronger for firms with low-quality credit ratings, consistent with auditors pricing lender monitoring.

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Most prior studies assume a positive relation between debt and earnings management, consistent with the financial distress theory. However, the empirical evidence for financial distress theory is mixed. Another stream of studies argues that lenders of short-term debt play a monitoring role over management, especially when the firm's creditworthiness is not in doubt. To explore the implications of these arguments on managers' earnings management incentives, we examine a sample of US firms over the period 2003-2006 and find that short-term debt is positively associated with accruals-based earnings management (measured by discretionary accruals), consistent with the financial distress theory. We also find that this relation is significantly weaker for firms that are of higher creditworthiness (i.e. investment grade firms), consistent with monitoring benefits outweighing financial distress reasons for managing earnings.

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Short-term hooking mortality was evaluated for three sparid species [Diplodus vulgaris (Geoffroy Saint-Hilaire), Spar-us aurata L. and Spondyliosoma cantharus (L.)] in the Algarve, south Portugal. Fishes were caught from the shore during October 2009 at a fish farm reservoir (Ria Formosa), using three different hook sizes. The relationships between hooking mortality and seven independent variables were analyzed using logistic regression models. In all,384 fishes representing the three target species were caught during the angling sessions. The most caught species was S. cantharus (n = 181; 100% undersized), followed by S. aurata (n = 137; 89% undersized) and D. vulgaris (n = 66; 97% undersized). Mortalities ranged between 0% for D. vulgaris and 12% for S. aurata (S. cantharus, 3%). For S. aurora, anatomical hooking location was the main predictor of mortality, with 63% of the fishes that died being deeply hooked. Our results support the current mandatory practices of releasing undersized fish for the studied species, given the low post-release mortality rates observed. (C) 2010 Elsevier B.V. All rights reserved.