Novel pearl millet couscous process for West African markets using a low-cost single-screw extruder

Traditional West African pearl millet couscous products are popular; however, their preparation is laborious, time-consuming and energy-demanding, involving agglomeration, steaming, drying and sieving steps. In this study, a process was developed to produce millet couscous using a high pressure, high temperature and low-cost single-screw extruder. The innovation was to directly process the cooked low-moisture extrudate to a couscous product by drying and milling to the appropriate particle size (ranging between 1 and 2 mm). Throughput for the traditional process as prepared for commercial sale is 50 kg per day, but with the same amount of labour, the extrusion process yields ~350 kg per day. A consumer sensory study held in Niamey (Niger) showed that the extruded millet couscous was comparable to traditional couscous, though this was dependent on selection of the proper millet variety. This novel extrusion process could stimulate small- to medium-scale manufacturing of couscous and couscous-type products in West Africa.     

Study of the effect of BDMA catalyst in the epoxy novolac curing process by isothermal DSC

Epoxy novolac/anhydride cure kinetics has been studied by differential scanning calorimetry under isothermal conditions. The system used in this study was an epoxy novolac resin (DEN431), with nadic methyl anhydride as hardener and benzyldimethylamine as accelerator. Kinetic parameters including the reaction order, activation energy and kinetic rate constants, were investigated. The cure reaction was described with the catalyst concentration, and a normalized kinetic model developed for it. It is shown that the cure reaction is dependent on the cure temperature and catalyst concentration, and that it proceeds through an autocatalytic kinetic mechanism. The curing kinetic constants and the cure activation energies were obtained using the Arrhenius kinetic model. A suggested kinetic model with a diffusion term was successfully used to describe and predict the cure kinetics of epoxy novolac resin compositions as a function of the catalyst content and temperature. Copyright © 2003 Society of Chemical Industry     

Continuous-wave quantum yields of various cobalamins are influenced by competition between geminate recombination and cage escape

Quantum yields of photolysis of the cobalt-carbon bond for three cobalamin compounds were measured with a continuous-wave laser at 442 nm under both aerobic and anaerobic conditions. Aerobically, the initial homolysis product, Co(II) cobalamin, is trapped by oxygen to form aquocobalamin. Use of an excess of the radical trapping reagent 2,2,6,6-tetramethyl-1-piperidinyloxyl, under anaerobic conditions, scavenges the carbon radical and allows detection of the cobalt(II) photoproduct. Quantum yields measured under anaerobic conditions for 5'-deoxyadenosylcobalamin (phi (Co-C alpha),442 = 0.20 +/- 0.03) and methylcobalamin (phi (Co-C alpha),442 = 0.35 +/- 0.03) are in agreement with the values obtained under aerobic conditions (phi (Co-C alpha),442 = 0.19 +/- 0.04 and phi (Co-C alpha),442 = 0.36 +/- 0.04, respectively). Additionally, the quantum yield values for 5'-deoxyadenosylcobalamin and its base-off derivative (phi (Co-C alpha),442 = 0.045 +/- 0.015) match those obtained on a nanosecond time scale [Chen, E., & Chance, M. R. (1990) J. Biol. Chem. 256, 12987-12994]. A comparison of quantum yields obtained anaerobically for 5'-deoxyadenosylcobalamin and methylcobalamin in H2O versus ethylene glycol shows a 4-fold decrease for the former cobalamin and no change for the latter. These quantum yields are evaluated in terms of time-independent radical separation distances.     

Perspectives on Design and Innovation

A series of studies of top European and other firms has revealed patterns of design management associated with commercial success. Firms that invest resources and professional expertise in product and industrial design in traditional and new industries have been commercially more successful than firms that pay less attention to these aspects of design. As an industry matures there is a shift in emphasis from design associated with technological innovation, to designs supporting technical improvements, and then to supporting user needs, fashion and product variants. These issues are illustrated through the history of the evolution of the bicycle.     

A comparison of CCS tandem overload controls

In this paper we analyse issues associated with overloads in tandem switching systems in Common Channel Signalling (CCS) networks. In particular, we examine the need for, and effectiveness of, Automatic Congestion Control (ACC), a CCS mechanism which allows a congested switching system to inform adjacent CCS nodes of its level of overload, and subsequently controls the rate at which traffic is sent to the congested node. We demonstrate the critical need for end-offices and tandem switching systems to implement some form of ACC if network performance is to be maintained during congestion, especially in tandem exchanges. In addition, we find that the presently defined ACC should be expanded to allow more levels of congestion to be reported to adjacent nodes, so that a more effective, finer grained control is produced.     

Spontaneous rise of fetal platelet counts despite increasing anti-HPA-5b antibodies

A 47-year-old woman with seronegative polyarthritis, diarrhea, and photosensitivity dermatitis was found to have Crohn's disease and pellagra. The presence of high values of 5-hydroxyindolacetic acid in the urine began the exhaustive investigations and finally enterotomy. No mass lesion was found. Argyrophilic cells were not increased in areas of inflamed intestinal mucosa or the normal mucosa. The disagreement between biochemical and histologic findings was attributed to sampling error. Antiinflammatory treatment for Crohn's disease was given and the gastrointestinal and articular symptoms improved, excretion of 5-hydroxyindolacetic acid returned to normal and there was no relapse of pellagra. Pellagra as a complication of Crohn's disease has been described in 4 cases; malnutrition and intestinal malabsorption were the proposed mechanisms for the niacin deficiency and pellagra of those patients. In the current case, the pathogenesis of pellagra may be accounted to wastage of tryptophan by an increased pool of intestinal argyrophilic cells, suggested by increased urinary excretion of 5-hydroxyindolacetic acid.     

Improved atrial function in bicaval versus standard orthotopic techniques in cardiac transplantation

Atrial geometry is preserved in the bicaval technique of cardiac transplantation. Using Doppler echocardiography, we investigated the impact of this technique on preservation of atrial function and found that echocardiographic indexes of atrial function are improved in bicaval cardiac transplants versus the standard orthotopic transplants.