65 resultados para foreign direct investment (FDI)


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This paper analyses the presence of financial constraint in the investment decisions of 367 Brazilian firms from 1997 to 2004, using a Bayesian econometric model with group-varying parameters. The motivation for this paper is the use of clustering techniques to group firms in a totally endogenous form. In order to classify the firms we used a hybrid clustering method, that is, hierarchical and non-hierarchical clustering techniques jointly. To estimate the parameters a Bayesian approach was considered. Prior distributions were assumed for the parameters, classifying the model in random or fixed effects. Ordinate predictive density criterion was used to select the model providing a better prediction. We tested thirty models and the better prediction considers the presence of 2 groups in the sample, assuming the fixed effect model with a Student t distribution with 20 degrees of freedom for the error. The results indicate robustness in the identification of financial constraint when the firms are classified by the clustering techniques. (C) 2010 Elsevier B.V. All rights reserved.

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This paper presents the results of a research on direct drinking water treatment through an ultrafiltration pilot plant unit using spiral-wound membranes (3500 MWCO). The source of water is the Guarapiranga Reservoir, an eutrophicated water body located in the metropolitan region of Sao Paulo, Brazil. The data were collected during a period of almost 3400 h, from August 2005 to January 2006. The main objective of the study was to evaluate the membrane production capacity and contaminant removal efficiency. It was verified that the system was able to produce a high quality permeate with a flow close to the specified by the membrane manufacturer. The average permeate flow was 19.7 L.h(-1).m(-2), at 467 kPa and 25 degrees C, with a global water recovery of almost 85%. The removal efficiencies for TOC, UV light absorption, and turbidity were 85%, 56%, and 95%, respectively. The results provide substantial evidence of the technical feasibility of spiral-wound UF membranes for direct drinking water treatment from euthrophicated sources, as an alternative for conventional drinking water treatment systems.

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This article discusses the impact on the profitability of firms under Complementary Law 102/2000 (which abrogated the Law 89/96 - Kandir Law) allowing the appropriation of ICMS credits, due to investment in fixed assets goods, at a ratio of 1/48 per month. The paper seeks to demonstrate how this new system - which resulted in the transformation of the ICMS as a value added tax (VAT) consumption-type to an income-type - leads to a loss of approximately 30% of the value of credits to be recovered and the effect it generates on the cost of investment and the profits for small, medium and large firms. From the methodological point of view, it is a descriptive and quantitative research, which proceeded in three stages. Initially, we have obtained estimated value of net sales and volume of investments, based on report Painel de Competitividade prepared by the Federacao das Indtustrias do Estado de Sao Paulo (Fiesp/Serasa). Based on this information, it was possible to obtain estimates of the factors of generation of debits and credits for ICMS, using the model Credit Control of Fixed Assets (CIAP). Finally, we have calculated three indicators: (i) present value of debt recovery/value of credits, (ii) present value of debt recovery / investment value, (iii) present value of debt recovery / sales profitability. We have conclude that the system introduced by Complementary Law 102/2000 implicates great opportunity cost for firms and that legislation should be reviewed from this perspective, aiming to ensure lower costs associated with investment projects.

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The present study describes the direct regeneration of protocorm-like bodies (PLBs) in leaf explants of the tropical species Oncidium flexuosum. The explants were inoculated in a solid, modified Murashige and Skoog (MS) medium with different concentrations of the growth regulator thidiazuron (TDZ) and with or without 2,4-dichlorophenoxyacetic acid (2,4-D) and naphthalene acetic acid (NAA), and kept away from light or in a 16-h photoperiod. The presence of auxins, 2,4-D, and NAA inhibited the formation of PLBs. The highest frequency of explants that regenerated PLBs (80%) was obtained when they were maintained in a culture medium containing 1.5 mu M TDZ under dark conditions. In the same culture medium but under a 16-h photoperiod, 95% of the leaf explants presented necrosis. Therefore, darkness was crucial for the regeneration of PLBs in O. flexuosum leaf explants, which is in disagreement with the literature. PLBs developed from the division of epidermal and subepidermal cells mainly on the adaxial side of the apex region of the explant. Plants with well-developed leaves and roots grew after the PLBs were transferred to growth regulator-free medium under a 16-h photoperiod.

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The use of remote sensing is necessary for monitoring forest carbon stocks at large scales. Optical remote sensing, although not the most suitable technique for the direct estimation of stand biomass, offers the advantage of providing large temporal and spatial datasets. In particular, information on canopy structure is encompassed in stand reflectance time series. This study focused on the example of Eucalyptus forest plantations, which have recently attracted much attention as a result of their high expansion rate in many tropical countries. Stand scale time-series of Normalized Difference Vegetation Index (NDVI) were obtained from MODIS satellite data after a procedure involving un-mixing and interpolation, on about 15,000 ha of plantations in southern Brazil. The comparison of the planting date of the current rotation (and therefore the age of the stands) estimated from these time series with real values provided by the company showed that the root mean square error was 35.5 days. Age alone explained more than 82% of stand wood volume variability and 87% of stand dominant height variability. Age variables were combined with other variables derived from the NDVI time series and simple bioclimatic data by means of linear (Stepwise) or nonlinear (Random Forest) regressions. The nonlinear regressions gave r-square values of 0.90 for volume and 0.92 for dominant height, and an accuracy of about 25 m(3)/ha for volume (15% of the volume average value) and about 1.6 m for dominant height (8% of the height average value). The improvement including NDVI and bioclimatic data comes from the fact that the cumulative NDVI since planting date integrates the interannual variability of leaf area index (LAI), light interception by the foliage and growth due for example to variations of seasonal water stress. The accuracy of biomass and height predictions was strongly improved by using the NDVI integrated over the two first years after planting, which are critical for stand establishment. These results open perspectives for cost-effective monitoring of biomass at large scales in intensively-managed plantation forests. (C) 2011 Elsevier Inc. All rights reserved.

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The recombinant apical membrane antigen 1 (AMA-1) and 19-kDa fragment of merozoite surface protein (MSP-1(19)) are the lead candidates for inclusion in a vaccine against blood stages of malaria due to encouraging protective studies in humans and animals. Despite the importance of an efficacious malaria vaccine, vaccine-related research has focused on identifying antigens that result in protective immunity rather than determining the nature of anti-malarial immune effector mechanisms. Moreover, emphasis has been placed on adaptive rather than innate immune responses. In this study, we investigated the effect of Plasmodium vivax vaccine candidates Pv-AMA-1 and Pv-MSP-1(19) on the immune response of malaria-naive donors. Maturation of dendritic cells is altered by Pv-AMA-1 but not Pv-MSP-1(19), as observed by differential expression of cell surface markers. In addition, Pv-AMA-1 induced an increased production of MIP-1 alpha/CCL3 and decreased production of TARC/CCL17 levels in both dendritic cells (DCs) and peripheral blood mononuclear cells (PBMCs). Finally, a significant pro-inflammatory response was elicited by Pv-AMA-1-stimulated PBMCs. These results suggest that the recombinant vaccine candidate Pv-AMA-1 may play a direct role on innate immune response and might be involved in parasite destruction. (C) 2007 Elsevier Ltd. All rights reserved.

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P>Thirty-five lymph node samples were taken from animals with macroscopic lesions consistent with Mycobacterium bovis infection. The animals were identified by postmortem examination in an abattoir in the northwestern region of state of Parana, Brazil. Twenty-two of the animals had previously been found to be tuberculin skin test positive. Tissue samples were decontaminated by Petroff`s method and processed for acid-fast bacilli staining, culture in Stonebrink and Lowenstein-Jensen media and DNA extraction. Lymph node DNA samples were amplified by PCR in the absence and presence (inhibitor controls) of DNA extracted from M. bovis culture. Mycobacterium bovis was identified in 14 (42.4%) lymph node samples by both PCR and by culture. The frequency of PCR-positive results (54.5%) was similar to that of culture-positive results (51.5%, P > 0.05). The percentage of PCR-positive lymph nodes increased from 39.4% (13/33) to 54.5% (18/33) when samples that were initially PCR-negative were reanalysed using 2.5 mu l DNA (two samples) and 1 : 2 diluted DNA (three samples). PCR sensitivity was affected by inhibitors and by the amount of DNA in the clinical samples. Our results indicate that direct detection of M. bovis in lymph nodes by PCR may be a fast and useful tool for bovine tuberculosis epidemic management in the region.

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Sibutramine hydrochloride monohydrate, chemically 1-(4-chlorophenyl)-N,N-dimethyl-alpha-(2-methylpropyl) hydrochloride monohydrate (SB center dot HCl center dot H2O), was approved by the U.S. Food and Drug Administration for the treatment of obesity. The objective of this study was to develop, validate, and compare methods using UV-derivative spectrophotometry (UVDS) and reversed-phase high-performance liquid chromatography (HPLC) for the determination of SB center dot HCl center dot H2O in pharmaceutical drug products. The UVDS and HPLC methods were found to be rapid, precise, and accurate. Statistically, there was no significant difference between the proposed UVDS and HPLC methods. The enantiomeric separation of SB was obtained on an alpha-1 acid glycoprotein column. The R- and S-sibutramine were eluted in < 5 min with baseline separation of the chromatographic peaks (alpha = 1.9 and resolution = 1.9).

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A wide range of polyfunctional aryl and heteroaryl zinc reagents were efficiently prepared in THF by using (TMP)(2)Mg center dot 2LiCl (TMP = 2,2,6,6-tetramethylpiperamidyl) in the presence of ZnCl(2). The possible pathways of this metalation procedure as well as possible reactive intermediates are discussed. This experimental protocol expands the tolerance of functional groups and allows an efficient zincation of sensitive heterocycles such as quinoxaline or pyrazine. The zincated arenes and heteroarenes react with various electrophiles providing the expected products in 60-95 % yield.

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A graphite furnace atomic absorption spectrometric method is proposed for the direct and simultaneous determination of Cd, Cu, and Se in human blood. Samples were diluted 1:10 (v/v) in 0.5% (v/v) HNO(3) + 0.5% (v/v) Triton X-100 solution. For 12 mu L injected sample volume + 5 mu L, of 1000 mg L(-1) Pd(NO(3))(2) + 3 mu L of 1000 mg L(-1) Mg(NO(3))(2), the calculated characteristic masses (mo) were 0.9 pg Cd, 16 pg Cu, and 39 pg Se, which are close to those mo values for single-element conditions for THGA furnace (1.3 pg Cd, 17 pg Cu, and 45 pg Se). Calibration curves with linear correlations better than 0.999 were obtained. The limits of detection (LOD) were 0.03 mu g L(-1) Cd, 0.075 mu g L(-1) Cu and 0.3 mu g L(-1) Se, and the relative standard deviations (n= 12) were 2.5%, 0.3%, and 1.5%, respectively. The method was applied for Cd, Cu, and Se determination in 10 human blood samples and the results were in agreement at the 95% confidence level with those obtained by inductively coupled plasma mass spectrometry. Concentrations of analytes in the selected blood samples varied from 1.7 to 3.2 mu g L(-1) Cd, 700 to 921.7 mu g L(-1) Cu, and from 68.6 to 350 mu g L(-1) Se. The accuracy of the proposed method was also evaluated by an addition-recovery experiment and recoveries of Cd, Cu, and Se added to blood samples ranged from 99-109%, 91-103%,and 93-103%, respectively.

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Annatto (AN), a natural food colorant rich in carotenoids, has been reported as being an effective antioxidant, but little is known about its potential chemopreventive properties. In this Study, we evaluated the ability of AN to protect human hepatoma cells (HepG2) from micronucleus (MN) induction against three different mutagens: benzo(a)pyrene (B(a)P), doxorubicin (DXR), and methyl methanesulfonate (MMS). In an attempt to clarify the possible mechanism of anti mutagenicity of AN, three protocols of treatment were applied (pretreatment; simultaneous treatment, and post-treatment with AN following treatment with the mutagens). Also, cells exposed only to AN were assayed for cytotoxicity and mutagenicity. A dosage up to 10 mu g/ml of AN was devoid of mutagenic activity. Protective effects were seen on micronuclei induced by B(a)P and DXR using pre and simultaneous treatment, but AN had no significant effect on MN induction by MMS in any of the protocols. Our results also show that exposure of cells to concentrations of AN higher than 10 mu g/ml decreased cell viability. Taken together, our findings indicate that AN presents antimutagenic activity in vitro, but its protective effect is dependent on the mutagen and on type of treatment suggesting its potential use as a chemopreventive agent. Environ. Mol. Mutagen. 50:808-814, 2009. (C) 2009 Wiley-Liss, Inc.

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We analyze the influence of time-, firm-, industry- and country-level determinants of capital structure. First, we apply hierarchical linear modeling in order to assess the relative importance of those levels. We find that time and firm levels explain 78% of firm leverage. Second, we include random intercepts and random coefficients in order to analyze the direct and indirect influences of firm/industry/country characteristics on firm leverage. We document several important indirect influences of variables at industry and country-levels on firm determinants of leverage, as well as several structural differences in the financial behavior between firms of developed and emerging countries. (C) 2010 Elsevier B.V. All rights reserved.

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The purpose of this paper is to analyze the dynamics of national saving-investment relationship in order to determine the degree of capital mobility in 12 Latin American countries. The analytically relevant correlation is the short-term one, defined as that between changes in saving and investment. Of special interest is the speed at which variables return to the long run equilibrium relationship, which is interpreted as being negatively related to the degree of capital mobility. The long run correlation, in turn, captures the coefficient implied by the solvency constraint. We find that heterogeneity and cross-section dependence completely change the estimation of the long run coefficient. Besides we obtain a more precise short run coefficient estimate compared to the existent estimates in the literature. There is evidence of an intermediate degree of capital mobility, and the coefficients are extremely stable over time.

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This paper addresses the investment decisions considering the presence of financial constraints of 373 large Brazilian firms from 1997 to 2004, using panel data. A Bayesian econometric model was used considering ridge regression for multicollinearity problems among the variables in the model. Prior distributions are assumed for the parameters, classifying the model into random or fixed effects. We used a Bayesian approach to estimate the parameters, considering normal and Student t distributions for the error and assumed that the initial values for the lagged dependent variable are not fixed, but generated by a random process. The recursive predictive density criterion was used for model comparisons. Twenty models were tested and the results indicated that multicollinearity does influence the value of the estimated parameters. Controlling for capital intensity, financial constraints are found to be more important for capital-intensive firms, probably due to their lower profitability indexes, higher fixed costs and higher degree of property diversification.

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Among marine invertebrates, the overall biomass invested in egg production varies widely within populations, which can result from the interaction of endogenous and exogenous factors. Species that have constant reproduction throughout the year can be good models to study the influence of environmental factors on reproductive processes. We conducted a seasonal comparison of egg production in the intertidal snapping shrimp Alpheus nuttingi, which shows a continuous reproductive pattern, to examine the hypothesis that differences in egg production are driven by environmental conditions and population features. This population showed an uncommon strategy, characterized by females that produce eggs of varying sizes within their clutches, with reduced egg volume when the number of eggs is higher (Spring-Summer). In these seasons, higher temperatures and greater food availability may allow the production of more eggs compared to the Autumn-Winter seasons. Compared to other alpheid shrimps, this population produces small eggs, but in larger numbers. Despite the higher fecundity, the reproductive output is relatively low, this production being supported by the large size of females from the southern Atlantic region. Our findings showed that the egg production of A. nuttingi was greatly influenced by environmental factors. Therefore, this shrimp, and probably other decapods that possess continuous reproduction, adopt different reproductive strategies during the year. (C) Koninklijke Brill NV, Leiden, 2010.