991 resultados para Maize and U. ruziziensis intercropped
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Using data from the International Revenue Service, this paper explores the effcts of corporate taxation on U.S. capital invested abroad and on tax planning practices (dividend payments, income shifting, and passive investment). The econometric analysis first indicates that investment is strongly influenced by average tax rates, with a magnified impact for particularly low-tax rates implying that the attractiveness of low-tax countries is not weakened by anti-deferral rules and cross-crediting limitations. Further explorations suggest that firms report higher profit and are less likely to repatriate dividends when they are located in low-tax jurisdictions. Firms also report higher Subpart F income in countries in which they shift their profit, suggesting that cross-crediting provides an incentive to shift passive income in low-tax countries and that passive investment can be an alternative strategy to minimize taxes when active investment opportunities are lacking. Finally, the paper estimates the role of effective transfer pricing regulation on income shifting activities using the quality of host countries' law enforcement. It appears that low degrees of law enforcement are associated with higher income-shifting.
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Decomposing crop residues in no-tillage system can alter soil chemical properties, which may consequently influence the productivity of succession crops. The objective of this study was to evaluate soil chemical properties and soybean, maize and rice yield, grown in the summer, after winter crops in a no-tillage system. The experiment was carried out in Jaboticabal, SP, Brazil (21 ° 15 ' 22 '' S; 48 ° 18 ' 58 '' W) on a Red Latosol (Oxisol), in a completely randomized block design, in strip plots with three replications. The treatments consisted of four summer crop sequences (maize monocrop, soybean monocrop, soybean/maize rotation and rice/bean/cotton rotation) combined with seven winter crops (maize, sunflower, oilseed radish, pearl millet, pigeon pea, grain sorghum and sunn hemp). The experiment began in September 2002. After the winter crops in the 2005/2006 growing season and before the sowing of summer crops in the 2006/2007 season, soil samples were collected in the layers 0-2.5; 2.5-5.0; 5-10; 10-20; and 20-30 cm. Organic matter, pH, P, K+, Ca2+, Mg2+, and H + Al were determined in each soil sample. In the summer soybean/maize rotation and in maize the organic matter contents and P levels were lower, in the layers 0-10 cm and 0-20 cm, respectively. Summer rice/bean/cotton rotation increased soil K levels at 0-10 cm depth when sunn hemp and oilseed radish had previously been grown in the winter, and in the 0-2.5 cm layer for millet. Sunn hemp, millet, oilseed radish and sorghum grown in the winter increased organic matter contents in the soil down to 30 cm. Higher P levels were found at the depths 0-2.5 cm and 0-5 cm, respectively, when sunn hemp and oilseed radish were grown in the winter. Highest grain yields for soybean in monoculture were obtained in succession to winter oilseed radish and sunn hemp and in rotation with maize, after oilseed radish, sunn hemp and millet. Maize yields were highest in succession to winter oilseed radish, millet and pigeon pea. Rice yields were lowest when grown after sorghum.
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Evidence exists that many natural facts are described better as a fractal. Although fractals are very useful for describing nature, it is also appropiate to review the concept of random fractal in finance. Due to the extraordinary importance of Brownian motion in physics, chemistry or biology, we will consider the generalization that supposes fractional Brownian motion introduced by Mandelbrot.The main goal of this work is to analyse the existence of long range dependence in instantaneous forward rates of different financial markets. Concretelly, we perform an empirical analysis on the Spanish, Mexican and U.S. interbanking interest rate. We work with three time series of daily data corresponding to 1 day operations from 28th March 1996 to 21st May 2002. From among all the existing tests on this matter we apply the methodology proposed in Taqqu, Teverovsky and Willinger (1995).
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In Brazilian agriculture, urea is the most commonly used nitrogen (N) source, in spite of having the disadvantage of losing considerable amounts of N by ammonia-N volatilization. The objectives of this study were to evaluate: N lossby ammonia volatilization from: [urea coated with copper sulfate and boric acid], [urea coated with zeolite], [urea+ammonium sulfate], [urea coated with copper sulfate and boric acid+ammonium sulfate], [common urea] and [ammonium nitrate]; and the effect of these N source son the maize yield in terms of amount and quality. The treatments were applied to the surface of a soil under no-tillage maize, in two growing seasons. The first season (2009/2010) was after a maize crop (maize straw left on the soil surface) and the second cycle (2012/2011) after a soybean crop. Due to the weather conditions during the experiments, the volatilization of ammonia-N was highest in the first four days after application of the N sources. Of all urea sources, under volatilization-favorable conditions, the loss of ammonia from urea coated with copper sulfate and boric acid was lowest, while under high rainfall, the losses from the different urea sources was similar, i.e., an adequate rainfall was favorablet o reduce volatilization. The ammonia volatilization losses were greatest in the first four days after application. Maize grain yield differed due to N application and in the treatments, but this was only observed with cultivation of maize crop residues in 2009/2010. The combination of ammonium+urea coated with copper sulfate and boric acid optimized grain yield compared to the other urea treatments. The crude protein concentration in maize was not influenced by the technologies of urea coating.
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Annual crop yield and nutrition have shown differentiated responses to modifications in soil chemical properties brought about by gypsum application. The aim of this study was to evaluate the effect of gypsum application rates on the chemical properties of a Latossolo Bruno (Clayey Oxisol), as well as on the nutrition and yield of a maize-barley succession under no-till. The experiment was set up in November 2009 in Guarapuava, Parana, Brazil, applying gypsum rates of 0.0, 1.5, 3.0, 4.5, and 6.0 Mg ha-1 to the soil surface upon sowing maize, with crop succession of barley. Gypsum application decreased the levels of Al3+ and Mg2+ in the 0.0-0.1 m layer and increased soil pH in the layers from 0.2-0.6 m depth. Gypsum application has increased the levels of Ca2+ in all soil layers up to 0.6 m, and the levels of S-SO4(2-) up to 0.8 m. In both crops, the leaf concentrations of Ca and S were increased while Mg concentrations have decreased as a function of gypsum rates. There was also an effect of gypsum rates on grain yield, with a quadratic response of maize and a linear increase for barley. Yield increases were up to 11 and 12 % in relation to control for the maximum technical efficiency (MTE) rates of 3.8 and 6.0 Mg ha-1 of gypsum, respectively. Gypsum application improved soil fertility in the profile, especially in the subsurface, as well as plant nutrition, increasing the yields of maize and barley.
Resumo:
Evidence exists that many natural facts are described better as a fractal. Although fractals are very useful for describing nature, it is also appropiate to review the concept of random fractal in finance. Due to the extraordinary importance of Brownian motion in physics, chemistry or biology, we will consider the generalization that supposes fractional Brownian motion introduced by Mandelbrot.The main goal of this work is to analyse the existence of long range dependence in instantaneous forward rates of different financial markets. Concretelly, we perform an empirical analysis on the Spanish, Mexican and U.S. interbanking interest rate. We work with three time series of daily data corresponding to 1 day operations from 28th March 1996 to 21st May 2002. From among all the existing tests on this matter we apply the methodology proposed in Taqqu, Teverovsky and Willinger (1995).
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The 1935 Iowa-Illinois Memorial Bridge is being documented at this time to fulfill the requirements of the Memorandum of Agreement regarding the removal of the Iowa-Illinois Memorial Bridge and the Iowana Farms Milk Company Building for the proposed improvements to Interstate 7 4 in Bettendorf, Iowa, and Moline, Illinois.1 The 1959 twin suspension bridge will be removed as well, but it was determined to be ineligible for the National Register of Historic Places. Discussion of the history of the 1959 twin span is included, however, in the current report as part of the overall history of the Iowa-Illinois Memorial Bridge. Fieldwork for the documentation occurred in November 2009 and October 2010 (Fig. 1). Limitations on photography included limited shoreline access on the Illinois side, making good views of the bridge from the south somewhat challenging. Also, photographs on the bridge deck were not possible because of interstate traffic and prohibitions on pedestrian traffic. Within the last few years, online primary sources have proliferated, along with historical materials regarding the Iowa-Illinois Memorial Bridge. Sources available online for this report included numerous historical photographs, as well as historical Davenport, Iowa, and U.S. newspapers that document the bridge planning and construction. Additional primary source material was found at the University of Iowa Libraries, the State Historical Society of Iowa in Iowa City, the Bettendorf Public Library, the Richardson-Sloane Special Collections Center at the Davenport Public Library, and the Iowa State University Special Collections in Ames.
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The U-Pb ages and the trace element content of zircon U-Pb along with major and trace element whole rock data on gabbroic dikes from the Lanzo lherzolitic massif, N-Italy, have been determined to constrain crustal accretion in ocean-continent transition zones. Three Fe-Ti gabbros were dated from the central and the southern part of the massif providing middle Jurassic ages of 161 +/- 2, 158 +/- 2 and 163 +/- 1 Ma, which argue for magmatic activity over few millions of years. Zircon crystals are characterized by high but variable Th/U ratios, rare earth element patterns enriched in heavy rare earths, pronounced positive Ce and negative Eu-anomalies consistent with crystallization after substantial plagioclase fractionation. The zircon trace element composition coupled with whole rock chemistry was used to reconstruct the crystallization history of the gabbros. A number of gabbros crystallized in situ, and zircon precipitated from trapped, intercumulus liquid, while other gabbros represent residual liquids that were extracted from a cumulus pile and crystallized along syn-magmatic shear zones. We propose a model in which the emplacement mechanism of gabbroic rocks in ocean-continent transition zones evolves from in situ crystallization to stratified crystallization with efficient extraction of residual liquid along syn-magmatic shear zones. Such an evolution of the crystallization history is probably related to the thermal evolution of the underlying mantle lithosphere.
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Chromium toxicity affects redox reactions within plant cells, generating detrimental reactive oxygen species. Glutathione is an antioxidant peptide and also a substrate for the production of phytochelatins, which are chelating peptides reported to mitigate Cr3+ toxicity in plants. In this study, Brachiaria brizantha (B. brizantha) and Brachiaria ruziziensis (B. ruziziensis) seedlings were evaluated for physiological responses and glutathione production following the addition of zero or 5 mg L-1 Cr3+ to the nutrient solution. Glutathione levels were determined by colorimetric analysis at 412 nm using 5,5'-dithio-bis(2-nitrobenzoic acid) as a chromophore reagent and recovery with glutathione reductase (with evaluations at days 10 and 20 of continuous growth). The assessments were carried out in a completely randomized design with 2 authentic replications, and arranged in a 23 factorial. Cr3+ caused an average increase of 0.76 mg g-1 in the initial glutathione content. However, by day 20 there was an average reduction of 3.63 mg g-1. Chromium-affected physiological detrimental responses, albeit detected in both species, were less-pronounced in B. ruziziensis, along with a much higher level of glutathione. This study indicates that B. ruziziensis has a greater tolerance for chromium toxicity than B. brizantha, and that glutathione is likely to be involved in the mitigation of chromium stress in B. ruziziensis.
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Twenty isolates of four fungal species, agents of "Helminthosporium" diseases in cereals, were collected from different regions: nine Bipolarisoryzae isolated from rice (Oryza sativa), seven B.sorokiniana from wheat (Triticum aestivum), two B. maydis, and two Exserohilumturcicum from maize (Zea mays). The strains were compared by PCR-RFLP and RAPD analysis. Size polymorphism among the isolates in the ITS region comprising the 5.8 S rDNA indicated genetic differences among the isolates, while a UPGMA phenogram constructed after the digestion of this region with restriction enzymes showed inter- and intra-specific polymorphism. The RAPD profiles indicated an expressive level of polymorphism among different species, compared with a low level of polymorphism among isolates of the same species. A UPGMA phenogram grouped the isolates according to the species and their host plant. RAPD profiles did not reveal polymorphism that directly correlated climatic factors with geographic source of the isolates of B. sorokiniana, and B. oryzae. Teleomorphic species revealed high similarity with their correspondent anamorphs.
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The use of saline water and the reuse of drainage water for irrigation depend on long-term strategies that ensure the sustainability of socio-economic and environmental impacts of agricultural systems. In this study, it was evaluated the effects of irrigation with saline water in the dry season and fresh water in the rainy season on the soil salt accumulation yield of maize and cowpea, in a crop rotation system. The experiment was conducted in the field, using a randomized complete block design, with five replications. The first crop was installed during the dry season of 2007, with maize irrigated with water of different salinities (0.8, 2.2, 3.6 and 5.0 dS m-1). The maize plants were harvested at 90 days after sowing (DAS), and vegetative growth, dry mass of 1000 seeds and grain yield were evaluated. The same plots were utilized for the cultivation of cowpea, during the rainy season of 2008. At the end of the crop, cycle plants of this species were harvested, being evaluated the vegetative growth and plant yield. Soil samples were collected before and after maize and cowpea cultivation. The salinity of irrigation water above 2.2 dS m-1 reduced the yield of maize during the dry season. The high total rainfall during the rainy season resulted in leaching of salts accumulated during cultivation in the dry season, and eliminated the possible negative effects of salinity on cowpea plants. However, this crop showed atypical behavior with a significant proportion of vegetative mass and low pod production, which reduced the efficiency of this strategy of crop rotation under the conditions of this study.