Single machine scheduling with small operator-non-availability periods

For an industrial application in the chemical industry, we were confronted with the planning of experiments, where human intervention of a chemist is required to handle the starting and termination of each of the experiments. This gives rise to a new type of scheduling problem, namely problems of finding schedules with time periods when the tasks can neither start nor finish. We consider in this paper the natural case of small periods where the duration of the periods is smaller than any processing time. This assumption corresponds to our chemical experiments lasting several days, whereas the operator unavailability periods are typically single days or week-ends. These problems are analyzed on a single machine with the makespan as criterion.     

Effect of phosphate binders on oxidative stress and inflammation markers in hemodialysis patients

It has been suggested that phosphate binders may reduce the inflammatory state of hemodialysis (HD) patients. However, it is not clear whether it has any effect on oxidative stress. The objective of this study was to evaluate the effect of sevelamer hydrochloride (SH) and calcium acetate (CA) on oxidative stress and inflammation markers in HD patients. Hemodialysis patients were randomly assigned to therapy with SH (n=17) or CA (n=14) for 1 year. Before the initiation of therapy (baseline) and at 12 months, we measured in vitro reactive oxygen species (ROS) production by stimulated and unstimulated polymorphonuclear neutrophils and serum levels of tumor necrosis factor α, interleukin-10, C-reactive protein, and albumin. There was a significant reduction of spontaneous ROS production in both groups after 12 months of therapy. There was a significant decrease of Staphylococcus aureus stimulated ROS production in the SH group. There was a significant increase in albumin serum levels only in the SH group. In the SH group, there was also a decrease in the serum levels of tumor necrosis factor α and C-reactive protein. Our results suggest that compared with CA treatment, SH may lead to a reduction in oxidative stress and inflammation. Therefore, it is possible that phosphate binders exert pleiotropic effects on oxidative stress and inflammation, which could contribute toward decreasing endothelial injury in patients in HD.     

Numerical Investigation of the Effect of Impeller Design Parameters on the Performance of a Multiphase Baffle‐Stirred Reactor

The turbulent gas‐liquid flow field in an industrial 100‐m³ stirred tank was calculated by using computational fluid dynamics based on the finite‐volume method. Turbulent effects were modeled with the shear stress transport model, and gas‐liquid bubbly flow was modeled with the Eulerian‐Eulerian approach using the Grace correlation for the drag force interphase momentum transfer. The relative motion between the rotating impeller and the stationary baffled tank was considered by using a multiple frames of reference algorithm. The effects of Rushton and pitched‐blade impeller design parameters such as blade geometry, location, and pumping direction on the mixing performance were investigated. It was found that a combination of Rushton turbines with up‐pumping pitched‐blade turbines provides the best mixing performance in terms of gas holdup and interfacial area density. The approach outlined in this work is useful for performance optimization of biotechnology reactors, as typically found in fermentation processes.     

Geodesign application for bio-swale design: rule-based approach stormwater management for Ottawa Street North in Hamilton,Ontario

With increases in storm frequency and intensity, municipalities are finding new ways of managing stormwater. Solutions require collaboration across planning disciplines and input from an informed public. This study compares a system of bioswales to existing curb and gutter infrastructure in a post-industrial streetscape of Hamilton, Ontario. Using the geodesign process, a section of Ottawa St. North was modelled to show how green infrastructure can ease the burden on aging, combined sewer systems. Qualitative data was gathered from residents of the neighbourhood through field notes, and quantitative geospatial data through GIS. Parametric modelling was used to generate a design, and scenarios created to show resulting impacts on stormwater run-off. The model was posted online as an interactive presentation, accessible to all stakeholders for review and comment. The results of the study demonstrate powerful new tools that can assist landscape architects in designing, collaborating and communicating stormwater strategies.     

Cross-cultural differences in recognizing affect from body posture

Conveyance and recognition of human emotion and affective expression is influenced by many factors, including culture. Within the user modeling field, it has become increasingly necessary to understand the role affect can play in personalizing interactive interfaces using embodied animated agents. However, little research within the computer science field aims at understanding cultural differences within this vein. Therefore, we conducted a study to evaluate if differences exist in the way various cultures perceive emotion from body posture. We used static posture images of affectively expressive avatars to conduct recognition experiments with subjects from three cultures. After analyzing the subjects' judgments using multivariate analysis, we grounded the identified differences into a set of low-level posture features. We then used Mixture Discriminant Analysis (MDA) and an unsupervised expectation maximization (EM) model to build separate cultural models for affective posture recognition. Our results could prove useful to aide designers in creating more effective affective avatars.     

Application of simulated annealing to the biclustering of gene expression data.

In a gene expression data matrix, a bicluster is a submatrix of genes and conditions that exhibits a high correlation of expression activity across both rows and columns. The problem of locating the most significant bicluster has been shown to be NP-complete. Heuristic approaches such as Cheng and Church's greedy node deletion algorithm have been previously employed. It is to be expected that stochastic search techniques such as evolutionary algorithms or simulated annealing might improve upon such greedy techniques. In this paper we show that an approach based on simulated annealing is well suited to this problem, and we present a comparative evaluation of simulated annealing and node deletion on a variety of datasets. We show that simulated annealing discovers more significant biclusters in many cases. Furthermore, we also test the ability of our technique to locate biologically verifiable biclusters within an annotated set of genes.     

The triple point of pure normal-deuterium

The triple point temperature of pure normal-deuterium was determined on IPTS-68 using a calorimetric technique in an adiabatic cryostat and samples of about 0.2 mol of deuterium, 99.86% pure, permanently sealed in small metal cells. The temperature value was found to be 18.729 ± 0.002 K. Two thirds of the quoted uncertainty was due to the differences in IPTS-68 calibrations from NBS, NPL and PRM); differences in a range of 4.2 mK were observed using five calibrated thermometers. Natural para-ortho conversion rate was observed to be 7 ± 2h^?1 at 18.7 K; the rate of conversion back to normal composition for the gas at 20 MPa and ambient temperature was 3 ± 1h¹. The enthalpy of melting was 199 ± 1 Jmol^?1.     

Allylsilanes and vinylsilanes from silylcupration of carbon-carbon multiple bonds: scope and synthetic applications

Silylcupration of multiple bonds (allenes, acetylenes, dienes, and styrenes) has become one of the most efficient procedures for the synthesis of vinyl- and allylsilanes. These substrates are useful building blocks in organic synthesis since they undergo a great variety of silicon-assisted transformations. The methodology reported has been widely used in the synthesis of different natural products, as well as in the construction of carbo- and heterocycles. In this Account, we wish to illustrate our contribution to this field, as well as to highlight the contributions of others.