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Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Geográfica is the property of Acta Geografica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phytate, the principal storage form of phosphorus in corn, is found to remain as a significant portion of phosphorus in the corn-ethanol coproducts streams. This poses concerns over poor digestion of these coproducts by monogastric animals and subsequent environmental issues on phosphorus. An ion-exchange-based process was developed to extract the phytate from thin stillage, which was selected as the influent based on the inositol phosphate distribution conducted on different corn-ethanol coproducts. Commercial industrial resins (IRA-93, IRA-68, IRA-900, IRA-400, and IRA-402) were characterized and screened for the phytate adsorption, specificity and capacity. Different types of eluents (NaOH, NaCl, NaHCO3, HCl, and NH4OH) were tested to evaluate the desorption capacity in all the six resins. Phytate-P isotherms and kinetics of the adsorption process, breakthrough profile on IRA-900 column and phytate elution curves were presented. This process yields a phytate-rich solution (11 g L-1), which is 25-fold concentrated compared to the concentration in thin stillage. The results show that the proposed retrofit process allows to leverage the existing corn-ethanol plants for high-value phytate production. [ABSTRACT FROM AUTHOR]

Project-based learning (PBL) is renowned as an active learning practice that promotes the application of the accumulation of knowledge through real-world and often open-ended problems. This work assesses a case evaluation of an introductory PBL course in a typical industrial engineering curriculum in Brazil. This course is taken during the first semester, in which students must develop solutions for a single given problem through weekly meetings. The case presented herein highlights the forced abrupt virtualization of the learning process, which imposed an unprecedented scenario on the students and instructors, especially with regard to this course, which is based primarily on presented discussions and activities. The first weeks of class following the abrupt virtualization of activities encountered misinformation and a lack of clarity about the adaptation of the activities. Fortunately, through rapid iterations, the adjustment process resulted in time invested by the students and classes, with an active discussion, using the tools made available by the university. This work aims to present the forced abrupt changes applied to this first-semester course, highlighting the challenges faced, and the positive outcomes obtained and observed by both the students and the instructor, and to make a comparison to the evolution of the course over the past years. [ABSTRACT FROM AUTHOR]

Sucrose, in contrast to glucose, is a lower-cost carbon source. This manuscript discloses that its use in submerged fungal growth promotes lipids more suitable to biodiesel production due to lower unsaturation indexes. The wild strain of Mucor circinelloides URM 4182, a potential source of microbial lipid, was grown on three sucrose-based carbon sources: commercial brown sugar, sugarcane juice, and sugarcane syrup, achieving biomass accumulation productivities up to 3.62 ± 0.04 g L−1 day−1, and lipid productivities as high as 0.93 ± 0.01 g L−1 day−1. Lipid extraction was performed using ethanol, a green alternative to petroleum-derived solvent, and characterized according to their fatty acid distribution, from which C16:0 and C18:1 stand as the most abundant fatty acids. Extracted lipids were converted to ethyl esters via lipase-catalyzed reactions achieving ester contents up to 97.4% and low contents of mono- and diacylglycerols (1.9% and 1.0%, respectively). The interest in utilizing sucrose-based sources is due to the wide abundance of such feedstock in sugarcane-producing regions, and due to the potential of increasing value to these low-cost carbon sources. The results presented herein demonstrate a simple, yet efficient, process of converting sucrose and its derivatives to microbial biodiesel using green-chemistry processes, such as lipid extraction using ethanol, avoiding the use of harsh and toxic chemicals commonly utilized, and enzyme-catalyzed reactions. [ABSTRACT FROM AUTHOR]