Kinetic characterization and modeling simplification of an anaerobic sulfate reducing batch process

BACKGROUND: A series of kinetic experiments for a sulfate reducing process was carried out in a batch laboratory reactor that allowed simplification of a model initially proposed for this system enabling establishment of the kinetic parameters. RESULTS: It was found that an incomplete oxidation of lactate is the most significant bio‐reaction occurring in the reactor; this fact led to model simplifications that allowed determination of the kinetic parameters. Sulfide and pH inhibition can be described using one inhibition term within the model equation, given the fact that sulfide inhibition is not present in the system. Kinetic parameters were obtained, yielding a maximum specific rate (µ_max/Y) of 2.17 ± 0.08 mg sulfate mg^?1 VSS min^?1. A zero‐order kinetics with respect to sulfate and a Monod affinity constant of 142.7 ± 64.9 mg L^?1 for the lactate were found. CONCLUSIONS: The final model for the process can be described by a single Monod term involving the lactate. This model resulted from the lack of sulfide inhibition in the system and the predominance of the partial lactate oxidation to acetate reaction over the complete lactate and acetate oxidation. Copyright © 2010 Society of Chemical Industry     

Differences in the sexual conditioned behavior of male and female Japanese quail (Coturnix japonica).

The conditioned responses of male and female Japanese quail (Coturnix japonica) were compared in a Pavlovian conditioning procedure in which presentation of a brief conditioned stimulus was immediately followed by the release of a copulation partner. Male quail vigorously approached the conditioned stimulus and were much more likely to enter the compartment housing their copulation partner than were female birds (Experiment 1). In females, sexual conditioning resulted in increased squatting (Experiment 2). This response was the reflection of sexual behavior rather than more general social behavior (Experiment 3). These findings provide the first definitive evidence of sexual learning in female quail and are consistent with the interpretation that sexual conditioning increases sexual arousal or receptivity in both sexes but the increase has different behavioral manifestations in male and female quail. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A centre–free approach for resource allocation with lower bounds

Since complexity and scale of systems are continuously increasing, there is a growing interest in developing distributed algorithms that are capable to address information constraints, specially for solving optimisation and decision-making problems. In this paper, we propose a novel method to solve distributed resource allocation problems that include lower bound constraints. The optimisation process is carried out by a set of agents that use a communication network to coordinate their decisions. Convergence and optimality of the method are guaranteed under some mild assumptions related to the convexity of the problem and the connectivity of the underlying graph. Finally, we compare our approach with other techniques reported in the literature, and we present some engineering applications.     

Phenotype markers in strains of Aeromonas isolated in Cuba from children with an acute diarrheic disease

Twenty-seven cases of Aeromonas isolated from 300 five-years children with acute diarrheal disease (EDA) were studied, with the aim for demonstrating the occurrence of some phenotypical markers associated with enteropathogenicity; among them were lysine decarboxylation, acetil methyl carbinol production, enterotoxigenicity, cytotoxicity and hemolysis. The percentage of analysed strains had two or more of the investigated markers, and 13 (48.1%) lysed the rabbit erythrocytes with titres higher than than 1:16. The presence of markers in Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae was demonstrated.     

Selenium species in buckwheat cultivated with foliar addition of Se(VI) and various levels of UV-B radiation

Common (Fagopyrum esculentum Moench) and tartary (Fagopyrum tataricum Gaertn.) buckwheat was treated by spraying the leaves with a water solution containing 15 mg Se per litre in the form of sodium selenate in the flowering period. The selenium content in all parts of plant was found to be less than 200 ng g⁻¹ in non-treated and in the range 2700–4650 ng g⁻¹ in selenium treated buckwheat. Exposure to UV-B radiation lead to higher Se accumulation in flowers of both Se enriched cultivars. For speciation analysis enzymatic hydrolysis was carried out, separation and detection of selenium species was performed by high performance liquid chromatography–ultraviolet treatment–hydride generation atomic fluorescence spectrometry (HPLC–UV–HG-AFS). In flowers and leaves, on average 11% of the Se content was soluble and in the form of Se(VI), representing between 0.6% (flowers) and 3% (leaves) of the Se content. The remaining soluble non-amino acid organic Se was not detected by HPLC–UV–HG-AFS. In seeds 93% of the selenium content was found in the extracts and the main selenium species was SeMet with 93 ± 5% relative to the selenium content.     

Effects of apple and pear varieties and pH on patulin accumulation by Penicillium expansum

BACKGROUND: Accumulation of patulin in apples and pears and subsequently in their by‐products is caused mostly by Penicillium expansum which causes blue mould. Fruit pH and other parameters are sometimes characteristic of a certain variety and thus the use of particular varieties might affect patulin content in the final products. The aim of this study was to evaluate the influence of fruit variety and pH on patulin accumulation. Patulin accumulation in both apple and pear juices at different pH and also in different apple varieties (Golden, Gala and Fuji) and pear varieties (Blanquilla and Conference) was assessed. RESULTS: The pH of juices significantly influenced patulin accumulation, especially in apple juice in which the highest amounts of patulin were detected at pH 3.5. In fruits, the pH values of the substrate were determinant only under cold storage. Thus, Golden apples, which presented a lower pH, accumulated more patulin at 1 °C. However, this trend was not observed at other temperatures in which varieties with higher amounts of organic acids (Golden and Fuji apples) accumulated most patulin. In the pear varieties, significant differences in pH did not lead to significant differences in patulin accumulation. CONCLUSION: Although pH influences patulin accumulation, other factors such as organic acid content may play an important role. Concerning the apple and pear varieties we studied, it seems that rather than variety, other parameters like pH or acidic content may be more important. These parameters vary significantly depending on the degree of ripeness of the fruit. Gala apple, which is used in Spanish juice production, was the only variety that accumulated dramatically higher amounts of patulin. Copyright © 2008 Society of Chemical Industry     

Evaluating the computational performance of the Xilinx Ultrascale+ EG Heterogeneous MPSoC

The Journal of Supercomputing - The emergent technology of Multi-Processor System-on-Chip (MPSoC), which combines heterogeneous computing with the high performance of Field Programmable Gate Arrays...     

Oligomeric poly(ether‐imide)s bearing ortho trifluoromethyl groups: Solubility,thermal studies,and optical properties

In the development of processable high‐temperature materials, six new aromatic poly(imide)s based on diamines containing ortho trifluoromethyl groups, ether linkages and R,R‐methylenes moieties (R = Me or Ph) and previously reported dianhydrides have been synthesized vía polycondensation reactions. All polymers were obtained with good yields, were soluble in a variety of polar aprotic solvents, and exhibited inherent viscosity (η_inh) values between 0.15 and 0.20 dL g^?1, which is indicative of low molecular‐weight species. Preliminary studies of their physical properties were carried out. The new materials were transparent in the visible region and they exhibited thermal decomposition temperatures ranging from 475 to 545 °C and glass‐transition temperatures varying from 288 to 304 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46613.     

A framework for decision-making in investment alternatives selection

Investment alternatives selection involves a variety of criteria that should be evaluated to provide a solid basis for decision-making. Some prior research has proposed methodologies and frameworks to support such alternatives selection. However, many of them present intrinsic limitations related to their applicability and complexity. Thus, this paper presents a framework for decision-making concerning investment alternatives that are usually related to equipment selection for a manufacturing process, technology selection for product development, product portfolio selection, and production strategy selection, among others. The framework is based on a multi-criteria approach that considers three main criteria: (i) strategy, which considers company market competitiveness; (ii) quality, which considers client requirements; and (iii) economic aspects, considering the overall financial benefits of the investment. These criteria are evaluated with the support of well-known tools from traditional management engineering such as SWOT, QFD, NPV and Payback. The results obtained through the use of these tools are rated using the MAUT method. Two major contributions are offered by this framework: (i) the integration of three key criteria for decision-making that enables to obtain a balanced analysis of the investment alternatives and (ii) the intrinsic easy-to-implement characteristic of the framework – based on the use of traditional tools. The proposed framework was applied in a tailor-made furniture company to support a make-or-buy decision, and the obtained results are discussed.