Free D- and L-Amino Acid Evolution During Sourdough Fermentation and Baking

The evolution of free D- and L-amino acids in sourdoughs started with various lactic acid bacteria (LAB) and yeasts was studied. Lactobacillus brevis subsp. lindneri CB1 and Lactobacillus plantrum DC400 had high proteolytic activity. During sourdough fermentation, Saccharomyces cerevisiae 141 and Saccharomyces exiguus M14 sequentially utilized free amino acids produced by bacterial activity. Due to increased cell yeast autolysis, more S. exiguus M14 inocula caused more free amino acids which were partially utilized by LAB without causing hydrolysis of wheat flour protein. D-alanine, D-glutamic acid and traces of other D-isomers were observed in sourdoughs fermented with L. brevis subsp. lindneri CB1 and S. cerevisiae 141. Free total D- and L-amino acid content decreased by more than 44% after baking the sourdoughs. No abiotic generation of new D-amino acid isomers was detected in the baked sourdoughs.     

Effects of Lactobacillus rhamnosus GG addition in ice cream

A 2⁴ full factorial experimental design was applied to verify the effects of Lactobacillus rhamnosus GG (LGG) addition in retail-manufactured ice cream stored at two different freezing temperatures (−16°C and −28°C) and containing two different levels of sugar (15–22%) and fat (5–10%). In addition to microbial counts, the pH, acidity, viscosity of the mixes and functional properties of the ice creams were evaluated. Both fresh and frozen-thawed LGG cells underwent preliminary resistance tests to bile, antibiotics and acidity. The LGG strain proved to be highly resistant to most of the stress factors. When the micro-organism was added to ice cream mixes in a quantity of 10⁸ cfu/g, it did not change the overrun, firmness or melting behaviour of the finished product. Regardless of formulation, no count decay of LGG cells was observed in ice cream stored for up to 1 year.     

The Notion of Industry and Knowledge Bases: The Evidence of Steel and Mini-mills

Drawing on the evidence of the steel sector, this essay suggestsa notion of industry in terms of sets of firms sharing the sameknowledge base. Industry segments are partitions of an industrycorresponding to given pieces of the sectoral knowledge andeach group of firms is defined in terms of the common domainof competence. The trajectory of competence development of themini-mills group is described and the paradigm of flexibility,which characterizes their organizational pattern, is discussed.     

Erythrocyte viscoelastic recovery after liver transplantation in a cirrhotic patient affected by spur cell anaemia

In physiological conditions, red blood cells (RBCs) are capable of dramatic deformations when passing through the microvasculature. This extreme deformability is closely related to the RBC biconcave shape, to the fluidic nature of the haemoglobin and the cell membrane structure, primarily consisting of a phospholipid bilayer with an underlying two-dimensional spectrin network. In many pathological and inflammatory conditions, the shape and the extreme deformability of erythrocytes appear to be significantly altered. These findings have stimulated intense research towards the search and validation of novel erythrocyte-based mechanical biomarkers, useful for disease diagnosis and therapy monitoring. In this study, we investigated with Atomic Force Microscopy (AFM) the mechanical properties of erythrocytes obtained from a 68 years old cirrhotic man diagnosed with spur cell anaemia and cold agglutinated disease, before and after liver transplantation. Mechanical changes are compared with ultrastructural alterations as studied by scanning electron microscopy and discussed according to confocal fluorescence microscopy results, showing possible alterations induced by the cirrhotic environment at the level of the RBCs cytoskeletal organisation and lipidic composition. Taken together, the results here presented show that liver transplantation not only contributes to restoring the proper RBC morphology, but it also induces recovery of the physiological viscous behaviour of cells, further stressing the relevance of viscous and dissipative forces in determining the RBC biomechanical response.     

Intermediate-Stage Densification in Vacuum Hot-Pressing of Alumina

The densification kinetics preceding the final-stage densification of Al₂O₃ hot-pressed in vacuum between 1150° and 1350°C and between 2000 and 6000 psi were analyzed. The analysis suggests a diffusion-controlled creep mechanism but is not necessarily consistent with a Nabarro-Herring vacancy model. The measured activation energy, 116 kcal/mol, agrees with the activation energy for the final stage of densification and for the self-diffusion of Al ions in Al₂O₃. It is proposed that the pore structure (i.e. open or closed) defines the stage of densification and, further, that pore structure has a profound effect on the apparent diffusion coefficients.     

Elastic Properties of Oxide Solid Solutions: The System Al2O3−Cr2O3

Sound velocities, densities, and lattice parameters of hot-pressed bodies of the solid-solution series Al₂O₃−Cr₂O₃ were investigated. Measured lattice parameters deviated slightly from Vegard's law. The compositional dependence of the longitudinal sound velocity agreed well with the predictions of Birch; the observed dependence of the bulk modulus on ionic volume did not agree with the relation of Anderson and Nafe.     

DEVELOPMENT AND EVALUATION OF AN EXTRUSION-TEXTURIZED PEANUT PROTEIN

A commercial defatted peanut flour was analyzed for texturization properties in a Wenger X-25 extruder. Extrusion of the flour with addition of sodium stearoyl-2-lactylate resulted in a steady state operation and uniform texturized products. Functional properties of the extrudates such as water retention, hardness, and product integrity upon retorting: were similar to those of textured soy protein. Organoleptic properties of prepared patties (30:70 hydrated textured protein to meat ratio) were not different from the all-meat control for the analyzed sample; cooking losses and shrinkage were lower. Flavor was the most limiting factor for higher levels of incorporation and acceptance. A scanning electron microscopy study showed correlation between microstructure and the properties of the extrudates.     

Towards a Knowledge-Based System for Seismic Assessment of Buildings

Aknowledge-based system, whose objectives are to support the procedures which lead to the seismic risk evaluation of buildings and to suggest possible retrofitting, is presented. The system architecture and its principal functions are described, with emphasis on the main part of the system: a model (“artificial world”) which describes the structure and possible behaviors of the building and its environment, at different definition levels, with qualitative and/or quantitative attributes.     

Two-Dimensional Transient Heat Conduction Analysis Using Spreadsheets

A method for using spreadsheets to perform a numerical analysis of one- and two-dimensional transient heat conduction is described. The numerical method is based on the explicit nodal equations and is described in terms of the thermal resistance and capacitance formulation. The spreadsheet setup uses an iteration macro and can use either a single-layer spreadsheet or multiple-layer linked spreadsheets. The method allows the use of various boundary conditions, including a specified surface temperature, insulated surfaces, a convective heal transfer coefficient distribution on any surface, and an equivalent radiation heat transfer coefficient. A variable grid can be used that allows a finer grid in areas of high gradients. Thermal properties may be heterogeneous and temperature dependent. The results are highly visual and can be easily plotted in two- and three-dimensional graphs.