937 resultados para share of no par value
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This paper sets forth a Neo-Kaleckian model of capacity utilization and growth with distribution featuring a profit-sharing arrangement. While a given proportion of firms compensate workers with only a base wage, the remaining proportion do so with a base wage and a share of profits. Consistent with the empirical evidence, workers hired by profit-sharing firms have a higher productivity than their counterparts in base-wage firms. While a higher profit-sharing coefficient raises capacity utilization and growth irrespective of the distribution of compensation strategies across firms, a higher frequency of profit-sharing firms does likewise only if the profit-sharing coefficient is sufficiently high.
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After Galileo's argument for the autonomy of science is analysed and adapted to take into account later developments of scientific practices, we conclude that, in the final analysis, it is not compelling. Nevertheless, Galileo's argument still provides a useful point of reference, for aspects of it can be interpreted to anticipate central components of the often acclaimed ideal of science as value free, so that appraising it contributes to the larger purpose of exploring how well that ideal stands up today. Finally, we will argue that residue from Galileo's struggle with the Church remains with us, making it difficult to identify the conditions that would need to be put into place today for any robust sense of the autonomy of science to be defensible. (C) 2011 Elsevier Ltd. All rights reserved.
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Background: Stable angina pectoris is a serious condition with few epidemiological studies in Brazil. Objective: To validate the short-version of the Rose angina questionnaire in Brazilian Portuguese for its implementation in surveys and longitudinal studies. Methods: A total of 116 consecutive patients from an outpatient clinic without prior myocardial infarction and/or coronary revascularization were enrolled for application of three questions of the Rose angina questionnaire addressing chest pain after exertion. We used the treadmill test as the gold standard with the Ellestad protocol. Results: The short-version of the Rose angina questionnaire of the 116 subjects submitted to the exercise treadmill test disclosed 89.7% of accuracy, 25% of sensitivity, 92.0% of specificity, 10.0% of positive predictive value, 97.2% of negative predictive value, and 3.1 of positive likelihood ratio and 0.82 of negative likelihood ratio. Conclusion: The Portuguese version with three items of the Rose angina questionnaire is suitable for epidemiological purposes. (Arq Bras Cardiol 2012; 99(5): 1056-1059)
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Aim The study aimed to determine the value of postchemoradiation biopsies, performed after significant tumour downsizing following neoadjuvant therapy, in predicting complete tumour regression in patients with distal rectal cancer. Method A retrospective comparative study was performed in patients with rectal cancer who achieved an incomplete clinical response after neoadjuvant chemoradiotherapy. Patients with significant tumour downsizing (> 30% of the initial tumour size) were compared with controls (< 30% reduction of the initial tumour size). During flexible proctoscopy carried out postchemoradiation, biopsies were performed using 3-mm biopsy forceps. The biopsy results were compared with the histopathological findings of the resected specimen. UICC (Union for International Cancer Control) ypTNM classification, tumour differentiation and regression grade were evaluated. The main outcome measures were sensitivity and specificity, negative and positive predictive values, and accuracy of a simple forceps biopsy for predicting pathological response after neoadjuvant chemoradiotherapy. Results Of the 172 patients, 112 were considered to have had an incomplete clinical response and were included in the study. Thirty-nine patients achieved significant tumour downsizing and underwent postchemoradiation biopsies. Overall, 53 biopsies were carried out. Of the 39 patients who achieved significant tumour downsizing, the biopsy result was positive in 25 and negative in 14. Only three of the patients with a negative biopsy result were found to have had a complete pathological response (giving a negative predictive value of 21%). Considering all biopsies performed, only three of 28 negative biopsies were true negatives, giving a negative predictive value of 11%. Conclusion In patients with distal rectal cancer undergoing neoadjuvant chemoradiation, post-treatment biopsies are of limited clinical value in ruling out persisting cancer. A negative biopsy result after a near-complete clinical response should not be considered sufficient for avoiding a radical resection.
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The objective of this study was to learn about the everyday eating behaviors and the social status of the families of malnourished children. This qualitative study involved eight families. Data were collected by participant observation and semi-structured interviews. Thematic analysis revealed the following themes: family eating; the family's social status and eating during childhood; and the presence of social programs and equipment. The family did not gather for meals and their food consisted basically of different sources of carbohydrates. Fruits and vegetables were very limited and considered to be food choices that did not provide sustenance. Differences were observed between the family's' and the children's' eating habits. Social programs and equipment provided important support, especially regarding the positive attachment with institutions and professionals and following the children's health. The family's social status does not allow the offering of appropriate quantities and quality of food throughout the month, thus compromising the nutritional status of the children, who are deprived of appropriate foods of adequate nutritional value.
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This paper addresses the importance of life cycle aspects in explaining the evolution of regional income inequality. The analysis of household microdata organized in age cohorts shows that Brazilian regional income inequality has different dynamics across generations, with income convergence being observed only for the older generations. The larger income share of younger generations produces a low speed of convergence in the country. When retirement payments, pensions, and other government transfers are excluded from income, convergence is not observed even for the older generations.
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This paper uses administrative data to follow Brazilian workers over time and examine what happens to the inter-regional wage differentials after controlling for unmeasured workers' characteristics that are fixed over time. Since the data allow us to track the same workers over the years, we are in the unusual position of obtaining the individual wages before and after the migration process. As a significant share of workers changed States in the sample period, it is possible to examine to what extent the wage differentials reflect the concentration of high-skilled individuals in some States. The results show that the overall wage variability across States drops to almost one third of its original value and the ranking of the State effects is significantly altered after we take into account the workers' fixed effects. A great deal of the inter-regional differentials, therefore, reflects differences in the average ability of workers across States.
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We present a simultaneous optical signal-to-noise ratio (OSNR) and differential group delay (DGD) monitoring method based on degree of polarization (DOP) measurements in optical communications systems. For the first time in the literature (to our best knowledge), the proposed scheme is demonstrated to be able to independently and simultaneously extract OSNR and DGD values from the DOP measurements. This is possible because the OSNR is related to maximum DOP, while DGD is related to the ratio between the maximum and minimum values of DOP. We experimentally measured OSNR and DGD in the ranges from 10 to 30 dB and 0 to 90 ps for a 10 Gb/s non-return-to-zero signal. A theoretical analysis of DOP accuracy needed to measure low values of DGD and high OSNRs is carried out, showing that current polarimeter technology is capable of yielding an OSNR measurement within 1 dB accuracy, for OSNR values up to 34 dB, while DGD error is limited to 1.5% for DGD values above 10 ps. For the first time to our knowledge, the technique was demonstrated to accurately measure first-order polarization mode dispersion (PMD) in the presence of a high value of second-order PMD (as high as 2071 ps(2)). (C) 2012 Optical Society of America
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Objective: This research aims to assess apprentices' and trainees' work conditions, psychosocial factors at work, as well as health symptoms after joining the labor force. Background: Despite the fact that there are over 3.5 million young working students in Brazil, this increasing rate brings with it difficult working conditions such as work pressure, heavy workloads, and lack of safety training. Method: This study was carried out in a nongovernmental organization (NGO) with 40 young members of a first job program in the city of Sao Paulo, Brazil. They filled out a comprehensive questionnaire focused on sociodemographic variables, working conditions, and health symptoms. Individual and collective semi-structured interviews were conducted. Empirical data analysis was performed using analysis of content. Results: The majority of participants mentioned difficulties in dealing with the pressure and their share of responsibilities at work. Body pains, headaches, sleep deprivation during the workweek, and frequent colds were mentioned. Lack of appropriate task and safety training contributed to the occurrence of work injuries. Conclusion: Having a full-time job during the day coupled with evening high school attendance may jeopardize these people's health and future. Application: This study can make a contribution to the revision and implementation of work training programs for adolescents. It can also help in the creation of more sensible policies regarding youth employment.
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In savannah and tropical grasslands, which account for 60% of grasslands worldwide, a large share of ecosystem carbon is located below ground due to high root:shoot ratios. Temporal variations in soil CO2 efflux (R-S) were investigated in a grassland of coastal Congo over two years. The objectives were (1) to identify the main factors controlling seasonal variations in R-S and (2) to develop a semi-empirical model describing R-S and including a heterotrophic component (R-H) and an autotrophic component (R-A). Plant above-ground activity was found to exert strong control over soil respiration since 71% of seasonal R-S variability was explained by the quantity of photosynthetically active radiation absorbed (APAR) by the grass canopy. We tested an additive model including a parameter enabling R-S partitioning into R-A and R-H. Assumptions underlying this model were that R-A mainly depended on the amount of photosynthates allocated below ground and that microbial and root activity was mostly controlled by soil temperature and soil moisture. The model provided a reasonably good prediction of seasonal variations in R-S (R-2 = 0.85) which varied between 5.4 mu mol m(-2) s(-1) in the wet season and 0.9 mu mol m(-2) s(-1) at the end of the dry season. The model was subsequently used to obtain annual estimates of R-S, R-A and R-H. In accordance with results reported for other tropical grasslands, we estimated that R-H accounted for 44% of R-S, which represented a flux similar to the amount of carbon brought annually to the soil from below-ground litter production. Overall, this study opens up prospects for simulating the carbon budget of tropical grasslands on a large scale using remotely sensed data. (C) 2012 Elsevier B.V. All rights reserved.
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In the last few years, the European Union (EU) has become greatly concerned about the environmental costs of road transport in Europe as a result of the constant growth in the market share of trucks and the steady decline in the market share of railroads. In order to reverse this trend, the EU is promoting the implementation of additional charges for heavy goods vehicles (HGV) on the trunk roads of the EU countries. However, the EU policy is being criticised because it does not address the implementation of charges to internalise the external costs produced by automobiles and other transport modes such as railroad. In this paper, we first describe the evolution of the HGV charging policy in the EU, and then assess its practical implementation across different European countries. Second, and of greater significance, by using the case study of Spain, we evaluate to what extent the current fees on trucks and trains reflect their social marginal costs, and consequently lead to an allocative-efficient outcome. We found that for the average case in Spain the truck industry meets more of the marginal social cost produced by it than does the freight railroad industry. The reason for this lies in the large sums of money paid by truck companies in fuel taxes, and the subsidies that continue to be granted by the government to the railroads.
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Previous studies have demonstrated that volatile organic compounds (VOCs), produced by the yeast Saccharomyces cerevisiae, were able to inhibit the development of phytopathogenic fungi. In this context, the nematicidal potential of the synthetic mixture of VOCs, constituted of alcohols and esters, was evaluated for the control of the root-knot nematode Meloidogyne javanica, which causes losses to crops of high economic value. The fumigation of substrate containing second-stage juveniles with VOCs exhibited nematicidal effect higher than 30% for the lowest concentration tested (33.3 µL g-1 substrate), whereas at 66.6 and 133.3 µL g-1 substrate, the nematode mortality was 100%. The present results stimulate other studies on VOCs for nematode management.
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A systematic approach to model nonlinear systems using norm-bounded linear differential inclusions (NLDIs) is proposed in this paper. The resulting NLDI model is suitable for the application of linear control design techniques and, therefore, it is possible to fulfill certain specifications for the underlying nonlinear system, within an operating region of interest in the state-space, using a linear controller designed for this NLDI model. Hence, a procedure to design a dynamic output feedback controller for the NLDI model is also proposed in this paper. One of the main contributions of the proposed modeling and control approach is the use of the mean-value theorem to represent the nonlinear system by a linear parameter-varying model, which is then mapped into a polytopic linear differential inclusion (PLDI) within the region of interest. To avoid the combinatorial problem that is inherent of polytopic models for medium- and large-sized systems, the PLDI is transformed into an NLDI, and the whole process is carried out ensuring that all trajectories of the underlying nonlinear system are also trajectories of the resulting NLDI within the operating region of interest. Furthermore, it is also possible to choose a particular structure for the NLDI parameters to reduce the conservatism in the representation of the nonlinear system by the NLDI model, and this feature is also one important contribution of this paper. Once the NLDI representation of the nonlinear system is obtained, the paper proposes the application of a linear control design method to this representation. The design is based on quadratic Lyapunov functions and formulated as search problem over a set of bilinear matrix inequalities (BMIs), which is solved using a two-step separation procedure that maps the BMIs into a set of corresponding linear matrix inequalities. Two numerical examples are given to demonstrate the effectiveness of the proposed approach.
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We report on four years of observations of 3C 273 at 7mm obtained with the Itapetinga radio telescope, in Brazil, between 2009 and 2013. We detected a flare in 2010 March, when the flux density increased by 50 per cent and reached 35 Jy. After the flare, the flux density started to decrease and reached values lower than 10 Jy. We suggest that the 7-mm flare is the radio counterpart of the γ -ray flare observed by the Fermi Large Area Telescope in 2009 September, in which the flux density at high energies reached a factor of 50 of its average value. A delay of 170 d between the radio and γ -ray flares was revealed using the discrete correlation function (DCF) that can be interpreted in the context of a shock model, in which each flare corresponds to the formation of a compact superluminal component that expands and becomes optically thin at radio frequencies at latter epochs. The differences in flare intensity between frequencies and at different times are explained as a consequence of an increase in the Doppler factor δ, as predicted by the 16-yr precession model proposed by Abraham & Romero. This increase has a large effect on boosting at high frequencies while it does not affect the observed optically thick radio emission too much. We discuss other observable effects of the variation in δ, such as the increase in the formation rate of superluminal components, the variations in the time delay between flares and the periodic behaviour of the radio light curve that we have found to be compatible with changes in the Doppler factor.
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In calcareous soils, which are a large share of agricultural soils worldwide, iron availability is limited. Consequently, the whole plant physiology is affected, because of the key role of iron in redox metabolism, resulting in reduced crop yield and quality. Peach cultivation is economically important in northern Italy, and is easily subjected to iron chlorosis. The management of iron nutrition in peach includes grafting on bicarbonate-tolerant rootstocks; other forms of management may be expensive and environmentally impacting. Four genotypes, used as rootstocks for peach and characterized by different degrees of tolerance to chlorosis, were tested in vitro on optimal and bicarbonate-enriched medium. Their redox status and antioxidant responses were assayed; the production and possible roles of nitric oxide (NO) and related compounds were also studied. The most sensitive genotypes show a stronger reduction of the antioxidant enzymatic activities and an increased oxidative stress. A high production of NO was found to be associated to resistant genotypes, whereas sensitive genotypes reacted to stress by downregulating nitrosoglutathione reductase activity. Therefore, NO is proposed to improve the internal iron availability, or to stimulate iron intake.