Flavor and Stability of "Horchata De Chufas"

Horchata is a sweetened water extract of chufa tubers (Cyperus esculentus) which is very popular in Spain, and has potential in the U.S. The objectives of this research were to characterize horchatas from different types of chufa, and to monitor flavor and stability of unheated and pasteurized horchatas during storage (2°C). Trained panelists rated the following attributes: color, chalkiness, sweetness, vanilla-like, nutty, earthiness, bitterness, and off-flavor. Horchatas made with chufa grown in Spain and chufa from Spain but grown in Florida showed higher vanilla and nutty levels than horchata from the Florida type. During storage (2°C), vanilla, nutty, and sweetness decreased, and other attributes increased. Heating to 70 and 95°C for 1 min did not alter sensory attributes initially, prevented off-flavor development, and slowed changes in desirable attributes for 35 days.     

FAULT-TOLERANT DESIGN OF BATCHER–BANYAN CLASS ATM SWITCHES

Many proposed packet switching systems for high-speed networks have employed the Batcher–banyan fabric due to its modular structure, self-routeing functionality, and distributed conflict-resolving mechanism. In this paper, we present a systematic fault-tolerant design for the Batcher–banyan class of switches. Our first concern is the development of an on-line error detection mechanism which is the prerequisite of any effective fault tolerant operation. Based on the technique developed by Davis, we propose a general fault-testing technique and verify it for a variety of unique-path self-routeing networks. Furthermore, we extend this method to Batcher sorting networks and construct a fault-tolerant Batcher sorter. Lastly, after contemplating the technique constraints and system performance, we deploy the above techniques into different levels of the Batcher–banyan networks and achieve a fault-tolerant version of the StarBurst switch, a member of the Batcher–banyan class of switches.     

Reducing information asymmetries in market entry decisions

A Bayesian belief network is adopted to structure and manage an entry decision problem, where a potential entrant has to evaluate the profitability of a given market, depending on an established firm's unknown and unobservable multidimensional type. A multiperiod multisignal model is defined to take account of strategic interaction processes between the incumbent and the potential competitor. Since significant theoretical and computational issues prevent us from finding optimal strategies, a myopic policy is discussed that leads to a reasonable outcome. An application example of the proposed solution procedure is also presented.     

POTENTIAL TOXICITY OF PYOVERDIN FROM PSEUDOMONAS ON MOUSE LIVER

Pseudomonas fluorescens were isolated from food and water. Bacterial strains were grown on synthetic medium and pyoverdin was purified with Fe³⁺. Iron was removed from some samples with 8-hydroxyquinoline to obtain free-pyoverdin. Purification was performed by chloroform/phenol, diethylether/water extractions, column chromatography and silica gel slabs. Mice were given water with pigment for prolonged periods to study the chronic effect on liver. Alanine amino transferase (ALT) and Aspartate amino transferase (AST) increased significantly in animals treated with pyoverdin-Fe, free-pyoverdin and heated pyoverdin. Sex dependence was not observed. The effect on hepatic enzymes was also studied employing chromatographic peaks separately and mixed. Analyses of variance for statistical evaluation was applied. Controls treated withpyoverdin-negative culture extract did not show amino transferase's increase. It was found that prolonged ingestion of pyoverdin can affect hepatic enzymes in mice.     

A UNIFIED COLLOCATION ALGORITHM FOR PACKED-BED CHEMICAL REACTOR SIMULATION

Mathematical models of packed-bed catalytic reactors are aimed to predict the conversions and temperature profiles in both fluid and solid phases within the reactor. Although very general models can be mathematically formulated, usually several simplifying hypothesis are introduced for the fluid phase and/or the solid phase, in order to overcome computational difficulties

We describe in this paper a computational algorithm based on Orthogonal Collocation Method on finite elements, with elimination of the knot unknown functions, coupled with an integration method for stiff ordinary differential equations. This has been used in the development of a computer code, which allows us to find the transient behavior of the reactor by solving the equation relative to the external field, coupled with those describing the transient behavior in the catalyst particles, for a wide class of reactor models. The most general examined model includes axial dispersion in the external fluid phase, interphase mass and heat transfer resistances, intraphase mass resistance and any given kinetic scheme with complex reaction rate expressions.     

THE LAMINAR FLOW TUBULAR REACTOR WITH HOMOGENEOUS AND HETEROGENEOUS REACTIONS I. Integral Equations for Diverse Reaction Rate Regimes

Design equations for non-isothermal Laminar Flow Tubular Reactors (LFTRs) with homogeneous and heterogeneous - at the reactor wall - reactions with arbitrary kinetic equations have been satisfactorily treated transforming the original P.D.E. problem into a system of integral equations. The kernels of the integral operators are related to an eigenvalue problem which does not depend on the kinetic equations; this avoids repetitive computational effort in the treating of different reaction kinetics.

To render a more efficient numerical treatment and according to the governing reaction rate regime, modified expressions of the general solution were obtained was follows: (i) a solution with kernels depending only on the diffusion and convective times was obtained for a low reaction regime; (ii) another solution with kernels including the reaction lime, besides the diffusion and convective ones, was necessary for a fast reaction regime and (iii) the local quasi-steady-state approximation was obtained as limiting case of solution (ii) for a instantaneous reaction regime.     

A SIMPLE METHOD TO DETERMINE DIFFUSION OF SODIUM IN THE EPIDERMIS OF GREEN OLIVES

The present study reports a simple method, both mathematical and experimental, to determine variable effective diffusion coefficients for sodium through the skins of olives. Skins removed from green olives, variety Arauco (also known as Criolla), were studied using a lye concentration of 2.25% (w/w) of NaOH at 20C. The diffusion of sodium was evaluated through fresh skins and previously alkali‐treated skins. The measured values of effective diffusion coefficients for untreated (fresh) olive skins increased two orders of magnitude during the processing time, from 10^?12 to 10^?10 m²/s. Whereas, the effective diffusion coefficients determined for previously treated olive skins were of the order of 10^?10 m²/s and increased very little with treatment time.     

AQUEOUS GARLIC EXTRACT AND MICROBIOLOGICAL QUALITY OF REFRIGERATED POULTRY MEAT

The antibacterial effect of garlic extract (5, 10 and 15%) was investigated on poultry carcasses obtained from a slaughterhouse, stored under refrigeration, and evaluated at selected time intervals. The effect of the garlic extract on the microbial contaminants of the poultry carcass surface – Salmonella, strict and facultative aerobic, mesophilic, and total and fecal coliforms – was evaluated. The garlic extract exhibited a concentration‐dependent reduction of microbial contamination. Garlic extract concentrations of 10 and 15% were the most effective. The bacteriostatic action of garlic extract against mesophilic microbiota can be observed until the third storage day. The count of total and fecal coliforms remained low during the storage period. Chicken feed was the apparent source of Salmonella contamination, and the aqueous garlic extract was not effective against Salmonella.