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In the wake of the importance of Brazilian agribusiness for national economy and production growth within the sugarcane-fuel sector, costs assessment of producing areas may improve the establishment of production. Current analysis identifies the differences in production costs of sugarcane in the northeastern region of Brazil, the traditional center-south area and the center-south expansion area with regard to harvests between 2007/2008 and 2011/2012 in Brazil. Descriptive research employed documental and technical procedures and a quantitative approach. Tukey's and Kruskal-Wallis's statistical tests identified which costs had the highest statistically significant variations among the regions. Results show that highest mean cost implies mechanization in the traditional and expansion center-south region, whereas man power is proper to the northeastern region. Mechanization, land rent and man power revealed statistically significant differences of the variables under analysis [ABSTRACT FROM AUTHOR]

The evaluation of the genetic transformability parameters of strains used in ethanol production industry such as cell viability, transformation efficiency and frequency of transformation are essential steps to identify which strains are the most adequate for breeding programs. This study aimed to evaluate the strains of budding yeast Saccharomyces cerevisiae that are more prone to genetic modification experiments, both those that are already used commercially, as well as strains isolated from distillery Japungú Agroindustrial S/A, where the standard strain MM10-2a was used as reference. All of them were subjected to transformation by chemical method (Liac/ ssDNA/PEG) with the expression vector pNatCre. The results showed that the highest and lowest cell viability were found, respectively, in strains GDBMF1-1 (P18A) and GDB226-1 (P19). The strain that showed the highest transformation efficiency was GDB24 (P5) and the lowest efficiency was observed in strains GDB114-2 (P18) and GDB226-1 (P19). The highest frequency of transformation, most important factor to be considered, was observed in the strain GDB24 (P5) and the lowest in GDB116-3 (P4A). The data showed that the industrial strain most suitable for experiments of genetic modification is GDB24 (P5) and the most suitable commercial strain is the CAT1. [ABSTRACT FROM AUTHOR]

With the purpose of evaluating the abundance of beetles (Scarabaeoidea) of the sugar cane area of Atencingo southward of the state of Puebla, captures were carried out during the period of 2000 to 2003 by using a screen-type light trap provided with a 120 watts mercury vapor light lamp, as well as direct collection under the public illumination and on tree and bush foliage. A total of 1253 specimens representing four families, six subfamilies, 11 tribes and 23 species of the genera Cotinis, Cyclocephala, Digitonthophagus, Diplotaxis, Epectinaspis, Ligyrus, Paranomala, Phileurus, Phyllophaga, Polyphylla, Ptichopus and Strategus were collected. Best represented genus was Phyllophaga with five species. Most abundant species were Cyclocephala lunulata and Phyllophaga brevidens, each with 534 and 539 specimens, respectively. A key to the 23 species is included. [ABSTRACT FROM AUTHOR]

Abstract: The combined sugar and ethanol production process from sugar cane is a paradigmatic application for energy integration strategies because of the high number of hot and cold streams involved, the external hot utility requirement at two temperature levels for juice evaporation and crystallization, and the electricity demand for juice extraction by milling. These conditions make it convenient to combine the sugar-cane process with a CHP system fuelled by bagasse, the main by-product from juice extraction. The strategies, tools and expertise on energy integration developed separately by the research teams authoring this paper are applied here jointly to optimize the synthesis and the design parameters of the process and of the total site starting from the basic idea of dissociating the heat exchanger network design problem from the total site synthesis problem. At first the minimization of the external heat requirement for the process alone is pursued and results show that a one third reduction can be achieved by optimal heat integration. Then the use of the by-product bagasse for on-site power generation is considered and two bagasse-fuelled CHP systems are optimized along with some parts of the sugar and ethanol production process in order to obtain maximum total site net power. Results show a variety of interesting scenarios of combined sugar, ethanol and electricity production plants with considerably high electricity output. [Copyright &y& Elsevier]

Abstract: In Brazil, sugar-cane crops are burned to facilitate harvesting, and this causes environmental pollution from the large amounts of smoke and soot that are released into the atmosphere. The smoke and soot contain numerous organic compounds such as PAHs. In this study, PM10 and PAH concentrations in the air of Araraquara (SE Brazil, with around 200,000 inhabitants and surrounded by sugar-cane plantations) were determined during the harvest and non-harvest seasons. The sampling strategy included two campaigns in each season, with 20 samples per season. PM10 was collected using a Hi-vol sampler with Teflon™ – coated glass fiber filters. PM10 ranged from 41 to 181 μg m−3 during the harvest season, and from 12 to 47 μg m−3 during the non-harvest season. The mean total concentration of PAHs was 2.5 ng m−3 (non-harvest season) and 11.6 ng m−3 (harvest season). In all sampling periods, the most abundant polycyclic aromatic hydrocarbons were phenanthrene and fluoranthrene, and the least abundant was anthracene. The cluster analysis of the total PAH concentrations for each day of sampling and the corresponding meteorological data suggested that the atmospheric concentration of PAHs was independent of the differences in the weather between the seasons. For both sampling seasons, the statistical treatment (PCA, Varimax rotation and HCA) indicated the presence of vehicle sources (diesel, gasoline, and natural-gas engines); but for the harvest season, the main source was attributed to sugar-cane burning. The data generated by this study indicated the burning of sugar-cane as the main contributor to the high levels of PAHs detected in samples during the sugar-cane harvest season. [Copyright &y& Elsevier]

Abstract: The fast sequential multi-element determination of Ca, Mg, K, Cu, Fe, Mn and Zn in plant tissues by high-resolution continuum source flame atomic absorption spectrometry is proposed. For this, the main lines for Cu (324.754 nm), Fe (248.327 nm), Mn (279.482 nm) and Zn (213.857 nm) were selected, and the secondary lines for Ca (239.856 nm), Mg (202.582 nm) and K (404.414 nm) were evaluated. The side pixel registration approach was studied to reduce sensitivity and extend the linear working range for Mg by measuring at wings (202.576 nm; 202.577 nm; 202.578 nm; 202.580 nm; 202.585 nm; 202.586 nm; 202.587 nm; 202.588 nm) of the secondary line. The interference caused by NO bands on Zn at 213.857 nm was removed using the least-squares background correction. Using the main lines for Cu, Fe, Mn and Zn, secondary lines for Ca and K, and line wing at 202.588 nm for Mg, and 5 mL min−1 sample flow-rate, calibration curves in the 0.1–0.5 mg L−1 Cu, 0.5–4.0 mg L−1 Fe, 0.5–4.0 mg L−1 Mn, 0.2–1.0 mg L−1 Zn, 10.0–100.0 mg L−1 Ca, 5.0–40.0 mg L−1 Mg and 50.0–250.0 mg L−1 K ranges were consistently obtained. Accuracy and precision were evaluated after analysis of five plant standard reference materials. Results were in agreement at a 95% confidence level (paired t-test) with certified values. The proposed method was applied to digests of sugar-cane leaves and results were close to those obtained by line-source flame atomic absorption spectrometry. Recoveries of Ca, Mg, K, Cu, Fe, Mn and Zn in the 89–103%, 84–107%, 87–103%, 85–105%, 92–106%, 91–114%, 96–114% intervals, respectively, were obtained. The limits of detection were 0.6 mg L−1 Ca, 0.4 mg L−1 Mg, 0.4 mg L−1 K, 7.7 µg L−1 Cu, 7.7 µg L−1 Fe, 1.5 µg L−1 Mn and 5.9 µg L−1 Zn. [Copyright &y& Elsevier]

Summary: An assessment of tolerance to water stress based upon measurements of cellular membrane thermostability and in vivo nitrate reductase activity (NRA) was made using young leaves of sugar‐cane (Saccharum officinarum L. commercial hybrids, Co 419, Co 740 and Co 1148) subjected to stress (51 to 61 d old) and subsequent hydration. An average reduction in leaf water potential (ΨL) from −0.97 to −1.91 MPa was associated with a decrease in NRA from 2.68 to 1.13 Ψmol g f. wt−1h−1, and an increase of the membrane injury from 30.8 to 70.9%. A highly significant positive correlation between ΨL and NRA and a negative correlation between ΨL and membrane injury were demonstrated. As ΨL declined, the concentration of malondialdehyde, a lipid peroxidation product, doubled. Following rehydration, at 63 d, increases in ΨL and NRA were higher than those of membrane thermostability and malondialdehyde concentration. [ABSTRACT FROM AUTHOR]

An assessment of tolerance to water stress based upon measurements of cellular membrane thermostability and in vivo nitrate reductase activity (NRA) was made using young leaves of sugar-cane (Saccharum officinarum L. commercial hybrids, Co 419, Co 740 and Co 1148) subjected to stress (51 to 61 d old) and subsequent hydration. An average reduction in leaf water potential (Ψ[SUBL]) from -0-97 to -1'91 MPa was associated with a decrease in NRA from 2.68 to 1.13 μmol g f. wt[SUP1] h[SUP1], and an increase of the membrane injury from 30'8 to 70.9%. A highly significant positive correlation between Ψ[SUBL] and NRA and a negative correlation between &Psi[SUBL] and membrane injury were demonstrated. As Ψ[SUBL] declined, the concentration of malondialdehyde, a lipid peroxidation product, doubled. Following rehydration, at 63 d, increases in Ψ[SUBL] and NRA were higher than those of membrane thermostability and malondialdehyde concentration. [ABSTRACT FROM AUTHOR]

An analysis of nutrient uptake by batch cultures of sugar-cane cells was performed to gain information about the ionic balance during uptake of charged metabolites. Whereas younger cultures (up to 1 week old) have to compensate excess cation influx with proton efflux, older cultures show balanced cation-anion uptake. Younger cells produce a small amount of carboxylic acids to furnish protons for charge compensation at the cytoplasmic membrane. Older cells synthesize organic acids more abundantly to generate protons necessary for the proton demand of nitrate and sulphate assimilation. Despite these assimilation reactions only a small percentage of carbon, which is taken up mainly as hexose, needs to be oxidized to carboxylic acids for that purpose. In contrast, younger cultures preferentially use the amino acids of the medium instead of assimilating nitrate. The use of amino acids as a nitrogen source does not require a significant part of metabolism for biochemical pH-stability, whereas an efficient proton circulation on the cytoplasmic membrane seems to be of major importance. A balance study of the main metabolized elements, carbon, nitrogen and sulphur was performed to get a quantitative impression of the fate of these nutrients during growth of cell cultures. [ABSTRACT FROM AUTHOR]