One-handed musicians-more than a gimmick.

There are many musicians with acquired limitations in making music, and there are many people with a disability who would like to play a music instrument in a modified way. There is discouragingly little information about this topic in literature. This article gives an overview of "making music in a modified way." It focuses on the possibilities for musicians with one-handed functionality to overcome problems with regards to their physical condition, insufficient muscle strength, or missing parts of the upper extremity. Five categories of possibilities for the functional one-handed musicians are described: 1. one-hand reconstructed instruments, 2. one-hand compositions, 3. adaptations of the instrument for the other hand, 4. prostheses to make it possible to play with both hands/arms, and 5. other techniques which enable the use of the leg(s). The solutions described make clear that playing music in an adaptive way requires an interdisciplinary approach. The purpose of this article is to inform, and to inspire, the healthcare professional about the many possibilities for functional one-handed musicians.

Implementation of in-line infrared monitor in full-scale anaerobic digestion process.

During start up but also during normal operation, anaerobic reactor systems should be run and monitored carefully to secure trouble-free operation, because the process is vulnerable to disturbances such as temporary overloading, biomass wash out and influent toxicity. The present method of monitoring is usually by manual sampling and subsequent laboratory analysis. Data collection, processing and feedback to system operation is manual and ad hoc, and involves high-level operator skills and attention. As a result, systems tend to be designed at relatively conservative design loading rates resulting in significant over-sizing of reactors and thus increased systems cost. It is therefore desirable to have on-line and continuous access to performance data on influent and effluent quality. Relevant variables to indicate process performance include VFA, COD, alkalinity, sulphate, and, if aerobic post-treatment is considered, total nitrogen, ammonia and nitrate. Recently, mid-IR spectrometry was demonstrated on a pilot scale to be suitable for in-line simultaneous measurement of these variables. This paper describes a full-scale application of the technique to test its ability to monitor continuously and without human intervention the above variables simultaneously in two process streams. For VFA, COD, sulphate, ammonium and TKN good agreement was obtained between in-line and manual measurements. During a period of six months the in-line measurements had to be interrupted several times because of clogging. It appeared that the sample pre-treatment unit was not able to cope with high solids concentrations all the time.

An integral dynamic model for the UASB reactor.

In this article a dynamic model of a continuous working UASB reactor is described. It results from the integration of the fluid flow pattern in the reactor, the kinetic behavior of the bacteria (where inhibition and limitation were taken into account), and the mass transport phenomena between different compartments and different phases. The mathematical equations underlying the model and describing the important mechanisms were programmed and prepared for computations and simulations by computer. The settler efficiency has to be over 99% to prevent the reactor from wash-out. When the settler efficiency is over 99%, the total sludge content of the reactor increases steadily, so the reactor is hardly ever in a steady state. This implies dynamic modeling. The model is able to predict the various observable and nonobservable or difficult to observe state variables, e.g., the sludge bed height, the sludge blanket concentration, the short-circuiting flows over bed and blanket, and the effluent COD concentration as a function of the hydrodynamic load, COD load, pH, and settler efficiency. The optimal pH value is between 6.0 and 8.0; fatty acid shock loadings are difficult to handle outside this optimal pH range.

Kinetics of anaerobic purification of industrial wastewater.

As a part of the development of an integral mathematical model describing the up-flow anaerobic sludge blanket (UASB) reactor, the kinetics of the conversion of organic wastes has to be known. We compared the Monod model with the model proposed by Andrews et al. Together with the assumption that the substrate for the anaerobic bacteria is formed by nonionized, volatile fatty acids, the Andrews model is able to describe substrate inhibition and reactor failure due to pH changes.From four batch experiments, with different concentrations of microorganisms, it could be concluded with a reliability of over 95% that the monod model was inadequate and Andrews' model was adequate to describe the measurements. Standard statistical techniques like the X2- and the F-test were used for this purpose. From a parameter sensitivity analysis for the Andrews model it followed that the maximum specific growth rate microAmax of the bacteria and the inhibition constant K1 are the parameters which influence the system most. Thus, these parameter were determined experimentally and most accurately. The results are: microAmax =16*10-4h-1+/-2% and K1 = 0.0158 g HAc/L+/-2.5%The other parameters were taken from literature. From calculation of the Thiele modulus for the particles it follows that transport limitation of the substrate in the flocs is not significant. The efficiency is 0.85 in the worst case..

Determination of chloramine T in dairy products.

A method has been developed for the quantitative determination of traces of chloramine T (Activin, Halamid) in dairy products. Proteins are removed and the hydrolysis product toluene-4-sulphonamide is extracted with ether. After evaporation of the solvent, the residue is oxidized with an alkaline potassium permanganate solution. The oxidized product is isolated by ether extraction and the residue is subjected to reduction with Raney Nickel catalyst in a sodium hydroxide solution. The sulphonamide group is split off and the benzoic acid thus formed is subjected to a gas chromatographic analysis.