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In the last decade, consumption and development of salad dressings has shown a continuous growing and their importance is increasing in Mexico and worldwide. These products are composed of oil, vinegar, spices, flavors and some hydrocolloids, among others. The formulation or specific composition is determinant on their characteristics and particularly, some physicochemical and flow properties. The objective of this study was to characterize and analyze a new salad dressing, and to observe how the incorporation of some components affects its properties. In order to study the physicochemical and flow behavior of a new mustard-vinaigrette salad dressing, different systems were elaborated. Two groups of samples were prepared; the first one included nine dressings or systems, with three different oil:vinegar rates and three mustard concentrations and stored four weeks. The second group consisted only of four systems with a constant concentration of mustard that were stored also through four weeks at two temperatures. Determinations of acidity, adhesivity, color, density, drop size, emulsion stability, flow properties, moisture, pH, retro-extrusion force, and water activity were carried out for most of the systems. Oil concentration had a significant effect on acidity, adhesivity, density, emulsion stability, flow properties, moisture, and water activity, in which the emulsifying capacity of the mustard was corroborated. The storage time showed a significant effect on adhesivity, emulsion stability, flow, luminosity and retro-extrusion properties. A modified Herschel and Bulkley model fitted better the flow behavior than other two equations. Analysis of variance allowed to know the significant effect of the studied variables on the yield stress, flow index and consistency coefficient obtained from the modified flow model.

Background: A set of nomograms based on the Dubbo Osteoporosis Epidemiology Study predicts the five- and ten-year absolute risk of fracture using age, bone mineral density and history of falls and low-trauma fracture. We assessed the discrimination and calibration of these nomograms among participants in the Canadian Multicentre Osteoporosis Study. Methods: We included participants aged 55-95 years for whom bone mineral density measurement data and at least one year of follow-up data were available. Self-reported incident fractures were identified by yearly postal questionnaire or interview (years 3, 5 and 10). We included low-trauma fractures before year 10, except those of the skull, face, hands, ankles and feet. We used a Cox proportional hazards model. Results: Among 4152 women, there were 583 fractures, with a mean follow-up time of 8.6 years. Among 1606 men, there were 116 fractures, with a mean follow-up time of 8.3 years. Increasing age, lower bone mineral density, prior fracture and prior falls were associated with increased risk of fracture. For low-trauma fractures, the concordance between predicted risk and fracture events (Harrell C) was 0.69 among women and 0.70 among men. For hip fractures, the concordance was 0.80 among women and 0.85 among men. The observed fracture risk was similar to the predicted risk in all quintiles of risk except the highest quintile of women, where it was lower. The net reclassification index (19.2%, 95% confidence interval [CI] 6.3% to 32.2%), favours the Dubbo nomogram over the current Canadian guidelines for men. Interpretation: The published nomograms provide good fracture-risk discrimination in a representative sample of the Canadian population. © 2011 Canadian Medical Association or its licensors.

International audience; Organizations of pre-hospital emergency medical services have as first mission to provide medical assistance to patients including transport to medical centers if necessary, and a second one that concerns the transfers of patients from one medical facility to another one. Most organizations in Canada and in North-America use two independent fleets to perform these missions. Although operating two separated fleets seems easier to do, it appears to be less efficient than an integrated fleet management approach able to deal with both types of demands. Taking this into consideration, this paper aims to design and evaluate the performance of three management approaches. This is a very challenging problem, since it involves solving simultaneously two difficult vehicle routing problems: an ambulance relocation problem and a dial a ride problem.

We examine and compare simulation-based algorithms for solvingthe agent scheduling problem in a multiskill call center.This problem consists in minimizing the total costs of agents underconstraints on the expected service level per call type,per period, and aggregated.We propose a solution approach that combines simulation withinteger or linear programming, with cut generation.In our numerical experiments with realistic problem instances,this approach performs better than all other methods proposedpreviously for this problem.We also show that the two-step approach, which is the standard methodfor solving this problem, sometimes yield solutions that arehighly suboptimal and inferior to those obtained by our proposed method.

Two extensions of the classical scheduling model with two parallel identical machines and a partially ordered set of unit execution time tasks are considered. It is well known that the Coffman-Graham algorithm constructs for this model a so-called ideal schedule: that is, a schedule which is optimal for both makespan and total completion time criteria simultaneously. The question of the existence of such a schedule for the extension of this model, where each task has a release time, has remained open over seneral decades. The paper gives a positive answer to this question and presents the corresponding polynormal-time algorithm.Another straightforward generalisation of the considered classcial model is obtained by the introduction of multiprocessor tasks. It is shown that, despite the fact tha a slightly modified Coffman-Graham algorithm solves the makespan problem with multiprocessor tasks for arbirtary precedence constraints, generally an ideal schedule does not exist and the problem with the criterion of total completion time turns out to be NP-hard ithe strong sense even for in-trees.