Synthesis of N,N-diethyl-N-{4-[(E)-(4-nitrophenyl)diazenyl]phenyl}amine via in situ diazotisation and coupling in supercritical carbon dioxide

The synthesis of azo dyes via a conventional aqueous-based diazotisation and coupling reaction requires the use of relatively high concentrations of mineral acids, which leads to high electrolyte concentrations in wastewater. Reported in this paper is an environmentally benign one-pot method for the synthesis of a nonionic azo dye, N,N -diethyl- N -{4-[( E )-(4-nitrophenyl)diazenyl]phenyl}amine, in supercritical carbon dioxide without using a mineral acid. The product yield increased significantly with temperature, with 91% theoretical yield afforded at 80 °C. The pressure of the system had little influence on product yield.     

Comparison of Etest to broth microdilution method for testing Streptococcus pneumoniae susceptibility to levofloxacin and three macrolides

When the Etest was compared to broth microdilution for susceptibility testing of Streptococcus pneumoniae, levofloxacin, erythromycin, and penicillin results correlated for both methods; azithromycin and clarithromycin showed discrepancies of > or = 2 dilutions for 95.8% and 31.5% of the isolates, respectively. Levofloxacin was active against 141 of 142 isolates (< or = 2.0 micrograms/ml), making it a potentially useful new fluoroquinolone.     

Self-organizing maps as a model of brain mechanisms potentially linked to autism.

The application of artificial neural networks in the study of psychopathological syndromes has great potential. Several computational models of acquired and developmental disorders, including autism, have been proposed recently. In this paper, we use the framework of self-organizing maps to study several aspects of autism, by modeling abnormalities in the learning process in biologically plausible manners. We then interpret the resulting feature maps with reference to autistic characteristics. The effects of manipulating the physical structure and size of self-organizing maps were measured and compared with the general characteristics of neural growth abnormalities in autistic children. We find no effect on stimuli coverage, but a negative impact on map unfolding, dependant on the intensity of the abnormality, but not the time of onset. We analyze sensory issues by introducing the concept of attention functions, used to model hypersensitivities and hyposensitivities. The issue of focus on details rather than the whole is analyzed through a model in which distant neighbors are explicitly rejected; we show the model may lead to improved coverage of finely-shaped areas or isolated stimuli, but poorer map unfolding. Finally, we consider effects of noisy communication channels on the development of maps, and show a strong sensitivity of both coverage and unfolding of maps.     

An expert PID controller uses refined ziegler and nichols rules and fuzzy logic ideas

This article proposes a scheme for the on-line adjustment of three mode controller settings based on experimental measurements of closed-loop performance. It uses a recently developed heuristic tuning procedure to identify estimated process parameters. This method may give rise to conflicting estimates. Fuzzy Set theory is applied to manage the situation in terms of a fuzzy conjunction to combine the various estimates. PID control was chosen because of its wide use in the industrial environment due to driving simplicity and robustness. The article shows design, development, and computer simulation aspects.     

Interactional Order and Constructed Ways of Seeing with Touchless Imaging Systems in Surgery

While surgical practices are increasingly reliant on a range of digital imaging technologies, the ability for clinicians to interact and manipulate these digital representations in the operating theatre using traditional touch based interaction devices is constrained by the need to maintain sterility. To overcome these concerns with sterility, a number of researchers are have been developing ways of enabling interaction in the operating theatre using touchless interaction techniques such as gesture and voice to allow clinicians control of the systems. While there have been important technical strides in the area, there has been little in the way of understanding the use of these touchless systems in practice. With this in mind we present a touchless system developed for use during vascular surgery. We deployed the system in the endovascular suite of a large hospital for use in the context of real procedures. We present findings from a study of the system in use focusing on how, with touchless interaction, the visual resources were embedded and made meaningful in the collaborative practices of surgery. In particular we discuss the importance of direct and dynamic control of the images by the clinicians in the context of talk and in the context of other artefact use as well as the work performed by members of the clinical team to make themselves sensable by the system. We discuss the broader implications of these findings for how we think about the design, evaluation and use of these systems.     

Enzyme‐catalyzed hydrolysis of poly(ethylene terephthalate) cyclic trimer

Oligoesters present in poly(ethylene terephthalate) fibers are commonly extracted from the fiber during processing, such as aqueous‐based dyeing. Aqueous, insoluble oligoesters, particularly cyclic trimers that precipitate on processing machinery and on the fiber surface are difficult to remove under benign conditions. Reported is a new method for the efficient removal of cyclic trimer by enzyme‐catalyzed hydrolysis. Almost complete hydrolysis of trimer was accomplished at pH 8 and 60°C. Effects of time, agitation, surfactant, and enzyme and trimer concentrations on the efficiency of hydrolysis are reported. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2545–2552, 2003     

Signage Versus Environmental Affordances: Is the Explicit Information Strong Enough to Guide Human Behavior During a Wayfinding Task?

This study aims to explore how people behave when they have to find a location within a complex building and are confronted with situations where directional signage (i.e., explicit information) is in opposition to environmental affordances that naturally direct users towards a specific path, creating a situation with conflicting information (e.g., a brighter corridor vs. a darker corridor but with a directional sign indicating to follow the darker one). A virtual reality–based methodology was used and a between‐subject design was considered. Thus, participants were given the tasks of finding three publicly accessible central points in a virtual hotel and confronted with a two forced‐choice task of local scenes in which environmental variables (i.e., corridor width and brightness) and signage varied systematically, in two experimental conditions (i.e., neutral and signage). For the signage condition, signs were inserted to explicitly point in the opposite direction than that implicitly suggested by the environmental affordances, creating situations with conflicting information. Results indicate that environmental variables were able to direct people indoors acting as environmental affordances. Users preferred to follow the wider and brighter paths. However, when directional signage pointed in the opposite direction of the paths preferred by the participants, most of them complied with signage.     

Minimising total tardiness in the m-machine flowshop problem: A review and evaluation of heuristics and metaheuristics

In this work, a review and comprehensive evaluation of heuristics and metaheuristics for the m-machine flowshop scheduling problem with the objective of minimising total tardiness is presented. Published reviews about this objective usually deal with a single machine or parallel machines and no recent methods are compared. Moreover, the existing reviews do not use the same benchmark of instances and the results are difficult to reproduce and generalise. We have implemented a total of 40 different heuristics and metaheuristics and we have analysed their performance under the same benchmark of instances in order to make a global and fair comparison. In this comparison, we study from the classical priority rules to the most recent tabu search, simulated annealing and genetic algorithms. In the evaluations we use the experimental design approach and careful statistical analyses to validate the effectiveness of the different methods tested. The results allow us to clearly identify the state-of-the-art methods.