869 resultados para Judgment Day.
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Due to the overwhelming international evidence that stock prices drop by less than the dividend paid on ex-dividend days, the ex-dividend day anomaly is considered a stylized fact. Two main approaches have emerged to explain this empirical regularity: the tax-clientele hypothesis and the microstructure of financial markets. Although the most widely accepted explanation for this fact relies on taxes, the ex-dividend day anomaly has been reported even in countries where neither dividends nor capital gains are taxed. The 2006 tax reform in Spain established the same tax rate for dividends and capital gains. This paper investigates stock returns on ex-dividend days in the Spanish stock market after the 2006 tax reform using a random coefficient model. Contrary to previous research, we do not observe an ex-dividend day anomaly. Unlike previous investigations, which are mostly concerned with suggesting explanations as to why this anomaly has occurred, we are in the somewhat strange position of discussing why this anomaly has not occurred. Our findings are robust across companies and stock dividend yields, thus supporting a tax--based explanation for the ex-dividend day anomaly.
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We present new optical and infrared photometric observations and high resolution H α spectra of the periodic radio star LSI+61◦303. The optical photometric data set covers the time interval 1985-1993 and amounts to about a hundred nights. A period of ∼26 days is found in the V band. The infrared data also present evidence for a similar periodicity, but with higher amplitude of variation ((0.m 2). The spectroscopic observations include 16 intermediate and high dispersion spectra of LSI+61◦303 collected between January 1989 and February 1993. The H α emission line profile and its variations are analyzed. Several emission line parameters -- among them the H α EW and the width of the H α red hump -- change strongly at or close to radio maximum, and may exhibit periodic variability. We also observe a significant change in the peak separation. The H α profile of LSI+61◦303 does not seem peculiar for a Be star. However, several of the observed variations of the H α profile can probably be associated with the presence of the compact, secondary star.
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The GMO Risk Assessment and Communication of Evidence (GRACE; www.grace-fp7.eu) project is funded by the European Commission within the 7th Framework Programme. A key objective of GRACE is to conduct 90-day animal feeding trials, animal studies with an extended time frame as well as analytical, in vitro and in silico studies on genetically modified (GM) maize in order to comparatively evaluate their use in GM plant risk assessment. In the present study, the results of two 90-day feeding trials with two different GM maize MON810 varieties, their near-isogenic non-GM varieties and four additional conventional maize varieties are presented. The feeding trials were performed by taking into account the guidance for such studies published by the EFSA Scientific Committee in 2011 and the OECD Test Guideline 408. The results obtained show that the MON810 maize at a level of up to 33 % in the diet did not induce adverse effects in male and female Wistar Han RCC rats after subchronic exposure, independently of the two different genetic backgrounds of the event
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The search for low subjectivity area estimates has increased the use of remote sensing for agricultural monitoring and crop yield prediction, leading to more flexibility in data acquisition and lower costs comparing to traditional methods such as census and surveys. Low spatial resolution satellite images with higher frequency in image acquisition have shown to be adequate for cropland mapping and monitoring in large areas. The main goal of this study was to map the Summer crops in the State of Paraná, Brazil, using 10-day composition of NDVI SPOT Vegetation data for 2005/2006, 2006/2007 and 2007/2008 cropping seasons. For this, a supervised digital classification method with Parallelepiped algorithm in multitemporal RGB image composites was used, in order to generate masks of Summer cultures for each 10-day composition. Accuracy assessment was performed using Kappa index, overall accuracy and Willmott's concordance index, resulting in good levels of accuracy. This methodology allowed the accomplishment, with free and low resolution data, of the mapping of Summer cultures at State level.
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After hatching, pullets are transported to brooding area and vaccinated. One day old chicks have not already developed thermoregulation ability; thus, brooding temperature variations may affect pullet quality leading to broiler meat production losses. This research aimed to calculate sensible heat loss in one day old pullets in hatching area and vaccination room. Ten one day old pullets were randomly selected from hatching area of a commercial hatchery. Infrared images were used to calculate bird surface temperature. Exposure areas for the two conditions were quantified, and both air temperature and wind speed was recorded. Total sensible heat loss was calculated as heat loss by radiation plus heat loss by convection. It was found that heat transfer occurs in different ways at different bird body parts. Total heat loss found for hatching baskets was equivalent to 0.81 J s-1 while for vaccination room was 1.16 J s-1. Pullet nutrition is based on energy loss from brooding to farm, and the overall pullet heat loss from hatchery to farm accepted is 13.95 J s-1. Thus, "starter feed" has relevant excess of energy input. These findings indicate that less energy can be used in initial feed, once heat loss is lower than assumed nowadays. Improved knowledge on these conditions may enhance broiler farm feeding strategies and economics during first rearing week.
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Kirja-arvio
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14 x 21 cm
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PURPOSE: To compare two single-agent chemotherapy (ChT) regimens evaluating, in first-line treatment, response and side effects and, in final single-agent treatment, the outcomes, among Brazilian patients with low-risk gestational trophoblastic neoplasia (GTN), according to International Federation of Gynecology and Obstetrics (FIGO) 2002. METHODS: Retrospective analysis of two concurrent cohorts with 194 low-risk GTN patients: from 1992 to 2012, as first-line treatment, 115 patients received 4 intramuscular doses of methotrexate alternated with 4 oral doses of folinic acid (MTX/FA) repetead every 14 days and, since 1996, 79 patients received an endovenous bolus-dose of actinomycin D (Act-D), biweekly. At GTN diagnosis, patient opinion was taken into consideration when defining the initial single-agent ChT regimen, and when there was resistance or toxicity to one regimen, the other drug was used preferentially. This study was approved by the Irmandade da Santa Casa de Misericórdia de Porto Alegre Ethical Committee. RESULTS: Both groups were clinically similar (p>0.05). In first-line treatments, frequency of complete response was similar (75.7% with MTX/FA and 67.1% with bolus Act-D); the number of ChT courses -median 3 (range: 1-10) with MTX/FA and 2 (range: 1-6) with bolus Act-D - and the time to remission -median 9 weeks (range: 2-16) with MTX/FA and 10 weeks (range: 2-16) with bolus Act-D) - were not different between the groups. In both groups, first-line side effects frequency were high but intensity was low; stomatitis was higher with MTX/FA (p<0.01) and nausea and vomit with Act-D (p<0.01). Final single-agent ChT responses were high in both groups (94.8% with MTX/FA and 83.5% with bolus Act-D; p<0.01) and 13% higher in the group initially treated with MTX/FA. Rates of hysterectomy and of GTN recurrence were low and similar. No patient died due to GTN. CONCLUSION: The two regimens had similar first-line ChT response. Final single-agent response rates were high and similar in both groups but the final single-agent remission rate was higher in the MTX/FA group.
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kuv., 20 x 27 cm
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kuv., 20 x 27 cm
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kuv., 19 x 38 cm
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An analysis was made of 30 four-day-old ostriches to evaluate their protein, metabolite, mineral, and serum enzyme profiles, to correlate them with the birds' sex. The values obtained were: Total proteins 3.59±0.72g/dL, albumin 1.04±0.14g/dL, globulins 2.51±0.56g/dL, A:G ratio 0.43± 0.07, total cholesterol 615.10±101.15mg/dL, high density lipoprotein cholesterol (HDL-C) 132.72±20.33mg/dL, low density lipoprotein cholesterol (LDL-C) 454.93±90.81mg/dL, very low density lipoprotein cholesterol (VLDL-C) 27.45±9.96mg/dL, triglycerides 137.23±49.78mg/dL, uric acid 6.24±2.15mg/dL, urea 18.27±12.33mg/dL, creatinine 0.30±0.04mg/dL, total calcium 9.38± 0.76mg/dL, ionized calcium 7.17±0.64mg/dL, phosphorus 6.96±0.91mg/dL, Ca:P ratio 1.37±0.21, iron 24.74±13.02µg/dL, sodium 142.03±6.17mEq/L, chlorides 109.59± 4.99mEq/L, aspartate aminotransferase (AST) 200.67±31.42 U/L, alanine aminotransferase (ALT) 3.90±1.92 U/L, γ-glutamyltransferase (GGT) 1.18±0.73 U/L, alkaline phosphatase (ALP) 597.30± 231.36 U/L, and creatine kinase (CK) 2348.30±755.60 U/L. Males and females showed significant differences in total proteins, globulins, alkaline phosphatase, A:G ratio, and uric acid.
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Electricity price forecasting has become an important area of research in the aftermath of the worldwide deregulation of the power industry that launched competitive electricity markets now embracing all market participants including generation and retail companies, transmission network providers, and market managers. Based on the needs of the market, a variety of approaches forecasting day-ahead electricity prices have been proposed over the last decades. However, most of the existing approaches are reasonably effective for normal range prices but disregard price spike events, which are caused by a number of complex factors and occur during periods of market stress. In the early research, price spikes were truncated before application of the forecasting model to reduce the influence of such observations on the estimation of the model parameters; otherwise, a very large forecast error would be generated on price spike occasions. Electricity price spikes, however, are significant for energy market participants to stay competitive in a market. Accurate price spike forecasting is important for generation companies to strategically bid into the market and to optimally manage their assets; for retailer companies, since they cannot pass the spikes onto final customers, and finally, for market managers to provide better management and planning for the energy market. This doctoral thesis aims at deriving a methodology able to accurately predict not only the day-ahead electricity prices within the normal range but also the price spikes. The Finnish day-ahead energy market of Nord Pool Spot is selected as the case market, and its structure is studied in detail. It is almost universally agreed in the forecasting literature that no single method is best in every situation. Since the real-world problems are often complex in nature, no single model is able to capture different patterns equally well. Therefore, a hybrid methodology that enhances the modeling capabilities appears to be a possibly productive strategy for practical use when electricity prices are predicted. The price forecasting methodology is proposed through a hybrid model applied to the price forecasting in the Finnish day-ahead energy market. The iterative search procedure employed within the methodology is developed to tune the model parameters and select the optimal input set of the explanatory variables. The numerical studies show that the proposed methodology has more accurate behavior than all other examined methods most recently applied to case studies of energy markets in different countries. The obtained results can be considered as providing extensive and useful information for participants of the day-ahead energy market, who have limited and uncertain information for price prediction to set up an optimal short-term operation portfolio. Although the focus of this work is primarily on the Finnish price area of Nord Pool Spot, given the result of this work, it is very likely that the same methodology will give good results when forecasting the prices on energy markets of other countries.