Compositional,biochemical and textural changes during ripening of Tulum cheese made with different coagulants

In the present study, biochemical, chemical and texture changes in Tulum cheeses made using calf rennet and microbial rennets (Aspergillus niger protease and Rhizomucor miehei protease) were compared during ripening for up to 90 days. A total of 15 free fatty acids (FFAs) were detected in the cheese samples. The peroxide values (PV) of the cheeses increased significantly (P < 0.05) during ripening and the cheese made with calf rennet had the highest PV. Proteolysis in the cheeses increased as the ripening time increased. α_s1‐casein and β‐casein degradation was higher in cheeses manufactured with R. miehei protease. Cheeses made with calf rennet were significantly (P < 0.05) harder, more adhesive, more cohesive and more resilient than those made with microbial rennet.     

Cellular neural network with trapezoidal activation function

This paper presents a cellular neural network (CNN) scheme employing a new non‐linear activation function, called trapezoidal activation function (TAF). The new CNN structure can classify linearly non‐separable data points and realize Boolean operations (including eXclusive OR) by using only a single‐layer CNN. In order to simplify the stability analysis, a feedback matrix W is defined as a function of the feedback template A and 2D equations are converted to 1D equations. The stability conditions of CNN with TAF are investigated and a sufficient condition for the existence of a unique equilibrium and global asymptotic stability is derived. By processing several examples of synthetic images, the analytically derived stability condition is also confirmed. Copyright © 2005 John Wiley & Sons, Ltd.     

Kigelia pinnata Seed Oil – A Moderate Source of Vernolic Acid

Vernolic acid represents 22.3% of the constituent fatty acids of the speed oil of an additional hitherto unexamined species of Bignoniaceae Kigelia pinnata. Its identification is based on comparative informations from thin-layer chromatography, infrared analysis, gas liquid chromatography and nuclear magnetic resonance spectroscopy with that of reference sample of Vernonia anthelmintica seed oil. The other fatty acids in this oil are: 14:0 (0.4), 16:0 (25.4), 18:0(0.9), 18:1 (8.9) and 18:2 (42.0%). K. pinnata is the first species of Bignoniaceae to be reported to contain vernolic acid in moderate amount.     

Energy profile of rollback-recovery strategies in high performance computing

Extreme-scale computing is set to provide the infrastructure for the advances and breakthroughs that will solve some of the hardest problems in science and engineering. However, resilience and energy concerns loom as two of the major challenges for machines at that scale. The number of components that will be assembled in the supercomputers plays a fundamental role in these challenges. First, a large number of parts will substantially increase the failure rate of the system compared to the failure frequency of current machines. Second, those components have to fit within the power envelope of the installation and keep the energy consumption within operational margins. Extreme-scale machines will have to incorporate fault tolerance mechanisms and honor the energy and power restrictions. Therefore, it is essential to understand how fault tolerance and energy consumption interplay. This paper presents a comparative evaluation and analysis of energy consumption of three different rollback-recovery protocols: checkpoint/restart, message logging and parallel recovery. Our experimental evaluation shows parallel recovery has the minimum execution time and energy consumption. Additionally, we present an analytical model that projects parallel recovery can reduce energy consumption more than 37% compared to checkpoint/restart at extreme scale.     

An analytical evaluation of the cutting forces in self-piloting drilling using the model of shear zone with parallel boundaries. Part 1: Theory

The performance of a self-piloting tool is affected by its design and geometry parameters. These parameters constitute the tool-force system which directly defines quality of the machined holes, tool life and required power. This paper presents an analytical approach to describe the cutting forces in self-piloting drilling. The approach is useful at the level of tool and process design. The subject has been covered in two parts. Part one deals with the analysis of the cutting mechanics employing the shear-zone model with parallel boundaries. The analysis of the continuity condition results in better understanding of the traditional cutting model's characteristics, such as the chip compression ratio and velocity diagram. Based on this analysis and using the thermomechanical model of the work-material resistance to cutting, a cutting-force model is proposed and has been verified experimentally.     

Expression and purification of beefy meaty peptide in <Emphasis Type=Italic>Pichia pastoris</Emphasis>

We established a gene expression process to produce a flavor peptide in Pichia pastoris. The octapeptide Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala was isolated from beef digested by papain, known as “beefy meaty peptide” (BMP). It was considered a savory seasoning in previous literatures. To produce BMP by microorganisms, BMP expression structures encoding tandem repeats of the octapeptide were designed and cloned in E. coli DH5α, then integrated into the AOX1 gene of Pichia pastoris GS115. Clones containing different BMP-gene copies, with 4-copy, 8-copy, 12-copy and 16-copy, were obtained and expressed in Pichia pastoris GS115. For the ease of purification, 6×His tag was fused to the C-termini of the peptides. As a result, the fusion peptides were successfully purified by His-tag bind affinity resin. The BMP fusion peptides with expected sizes were secreted from the resulting strains of P. pastoris GS115.     

Selective separation of cobalt and nickel by supported liquid membranes

The selective separation of cobalt from acidic media, containing both equimolar and nonequimolar mixtures of cobalt and nickel, was examined by supported liquid membranes using Alamine 336 as mobile carrier dissolved in various diluents. The membrane support was microporous hydrophobic polypropylene Celgard 2500 (25 μm thick, 0.209 × 0.054 μm pore size and 55% porosity). Acetic acid-Na acetate buffer was used for the adjustment of the feed pH which was critical. Various parameters were experimentally studied and the optimum conditions were determined.     

Effects of Durian Seed Flour on Processing Torque,Tensile, Thermal and Biodegradation Properties of Polypropylene and High Density Polyethylene Composites

Composites containing various percentage of durian seed flour (DSF) in the polypropylene (PP) and high density polyethylene (HDPE) have been compounded using an internal mixer. The processing torque, tensile, thermal and biodegradation properties have been determined. The incorporation of DSF increases stabilization torque and had adversely affected the mechanical properties by reducing the tensile strength and elongation at break, while the elastic modulus is increased, as starch content increases. At similar filler content, DSF filled PP showed higher tensile strength and elastic modulus, while lower in elongation at break than DSF-filled HDPE. The scanning electron microscopy (SEM) of tensile fracture specimens revealed good adhesion and dispersion of the DSF granules in the polymer matrix. However, the SEM results showed agglomeration of the DSF at higher filler content in the polymer and hence revealed poor wetting between DSF granules and polymer. The TGA results showed that both of the composites systems with higher filler content have higher initial degradation temperatures, T₀, degradation temperatures, T_deg and total weight loss. A simple biodegradability test conducted on each composite system shows that composites are subjected to biodegradation, judging by the significant increase in carbonyl and hydroxyl index of the composites after the test.     

Friedel-Craft Reaction of Glutaric Anhydride with benzene and toluene

The reaction of glutaric anhydride with benzene and toluene has been thoroughly studied. 4,4-Diphenyl-pent-4-enoic acid and 1,3-dibenzoyl propane were isolated as by-products of the reaction with benzene. The mechanism of formation of the by-products has been proved. In case of toluene no by-products were detected.