Atmospheric-pressure dielectric barrier discharge generation by a full-bridge flying capacitor multilevel inverter

A new configuration of a resonant full-bridge flying capacitor multicell inverter has been designed and constructed with the aim of achieving an extended output voltage frequency range with low harmonic distortion and reduced semiconductor commutation losses. This configuration was tested as a power supply for two different coaxial dielectric barrier discharge reactors, one of them employed for electric characterization and the other one for inorganic compound elimination in an aqueous solution. Two different gas mixtures, 90% Ar–10% O_2 and80% Ar–20% O_2, were individually supplied during the experiments; the results showed a highefficiency removal of meta-cresol(m-cresol) to the order of 98%, which was obtained by adding more oxygen to the plasma gas mixture.     

Nanostructured, molecularly imprinted, and template-patterned polythiophenes for chiral sensing and differentiation

An innovation to thin-film molecular imprinting is presented for the sensitive detection and effective discrimination of chiral compounds using a portable quartz crystal microbalance transduction technique. The facile approach involves i) colloidal sphere layering of latex particles onto the surface via a Langmuir-Blodgett-like technique followed by ii) template molecular imprinting using electrodeposition of a single functional and cross-linking monomer.     

Eigenvalue translation method for stabilizing an unsymmetric Lanczos reduction process

The Unsymmetric Lanczos Reduction method has been recently developed to reduce the size of a large-scale linear system which is the discretized form of a time-dependent partial differential equation problem with a large physical domain. This has been applied to solve the time-dependent advection–dispersion equation discretized by finite element or finite difference methods. However, the reduced system sometimes suffers time instability because of relocation of the approximate eigenvalues into the left half plane. This paper develops a method for stabilizing the reduced system while preserving the accuracy of the solution. The unstable eigenvalues are translated from the left half complex plane to the right half, leaving eigenvalues in right half plane unchanged. The results of numerical simulations of the synthetic and practical field contaminant transport problems show the efficiency and accuracy of this method. © 1998 John Wiley & Sons, Ltd.     

Electrochemical method for the detection of lipase activity

A novel electrochemical technique for the general assay of lipase activity is described. The method utilizes a solid-supported lipase substrate, which is formed by dripping and drying a small amount of an ethanol solution of 9-(5'-ferrocenylpentanoyloxy)nonyl disulfide (FPONDS) onto gold modified by a hexanethiol self-assembled monolayer. The redox ferrocene group of FPONDS generates the electrochemical signal, the intensity of which is proportional to the number of FPONDS molecules at the interface. Electrochemical and surface-enhanced infrared absorption spectroscopic data, as well as control experiments with an engineered, deactivated mutant enzyme, demonstrate that the wild-type lipase from Thermomyces lanuginosus is capable of cleaving the ester bonds of FPONDS molecules via an enzymatic hydrolysis mechanism, which includes the adsorption of the lipase onto the substrate surface. The hydrolysis liberates the ferrocene groups from the interface triggering a decay of the electrochemical redox signal. The rate of the electrochemical signal decrease is proportional to the lipase activity/concentration. These data suggest a general method for the direct measure of enzymatic activity of lipases.     

杂环取代联苯聚醚酮的流变行为

用日本岛津ＡＧ－２０００Ａ毛细管流变仪，研究了自制的杂环取代联苯型聚醚酮的流变行为。求出了表观流动活化能，考察了巴氏效庆和非牛顿行为，对其加工行为进行了分析。     

In defense of deception.

Comments that A. Ortmann and R. Hertwig's (see record 1997-04731-011) call to outlaw the use of all forms of deception in psychological research is both methodologically unsound and ethically misguided. Deception procedures differ so much in the nature and degree of deception used that even the harshest critic would be hard-pressed to state unequivocally that all deception is unacceptable. When the methodological requirements of an investigation lead the researcher to conclude that the only way a study can be carried out is by using deceptive tactics, the decision to deceive necessarily results in additional ethical responsibilities for the researcher, and the degree of deception should be held at a level that does not exceed what is required by the research. An absolute rule prohibiting the use of deception in all psychological research would have the egregious consequence of preventing researchers from carrying out a wide range of important studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Book reviews

BT Environment City Bulletin: The Big Picture - all eight topics under one roof Edited by C. Wood, 1994, Lincoln, The Wildlife Trusts, 110pp., £19.00 for local authorities, £14.00 for local businesses, £9.00 for voluntary groups.

Theme Parks, Leisure Centres, Zoos and Aquaria Anthony and Patricia Wylson, 1994, Harlow, Longman, 183pp. ISBN 0 582 09928 5, hb £60.00

The Picturesque Landscape: Visions of Georgian Herefordshire Edited by Stephen Daniels and Charles Watkins, 1994, Department of Geography, University of Nottingham, 100pp. ISBN 0 85358 033 2, £7.50

The Countryside Ideal: Anglo-American Images of Landscape Michael Bunce, 1994, London, Routledge, 232pp. ISBN 0 415 10435 1

Ordering Space: Types in Architecture and Design Karen A Frank and Lynda H Schneekloth (eds.), 1994, New York, Van Norstrand Reinhold, 383pp ISBN 0 442 01233 0, pb £34.50     

Dietary sodium restriction impairs insulin sensitivity in noninsulin-dependent diabetes mellitus

Dietary sodium restriction has a variety of effects on metabolism, including activation of the renin-angiotensin system. Angiotensin II has complex metabolic and cardiovascular effects, and these may be relevant to the effects of both nonpharmacological and pharmacological interventions in noninsulin-dependent diabetes mellitus (NIDDM). We have assessed the effect of dietary sodium restriction on insulin sensitivity and endogenous glucose production in eight normotensive patients with diet-controlled NIDDM who underwent hyperinsulinemic clamp studies in a randomized, double-blind, placebo-controlled cross-over protocol after two 4-day periods on sodium replete (160 mmol/day) and sodium deplete (40 mmol/day) diets. Mean +/- SD 24-h urinary sodium was 197 +/- 76.0 mmol (replete) and 67 +/- 19.5 mmol (deplete), P = 0.03. Insulin sensitivity was 42.0 +/- 11.3 mumol/kg.min (replete) and 37.0 +/- 11.6 mumol/kg.min (deplete), P = 0.04 (a reduction of 12%). Blood pressure was 130 +/- 21/78 +/- 11 mmHg (replete) and 128 +/- 12/73 +/- 10 mmHg (deplete). Dietary sodium restriction may result in a decrease in peripheral insulin sensitivity in normotensive patients with NIDDM, possibly via an elevation in prevailing angiotensin II concentrations.     

Parallel implementations of individual-based models in biology: bulletin- and non-bulletin-board approaches

Low-field magnetic resonance imaging (MRI) was performed on the stifle joints of four normal adult mongrel dogs using a 0.064 Tesla scanner. Markers were placed on each stifle joint to serve as reference points for comparing gross sections with the images. A T1-weighted sequence was used to image one stifle joint on each dog in the sagittal plane and the other stifle joint in the dorsal plane. The dogs were euthanized immediately following MRI and the stifle joints frozen intact. Each stifle joint was then embedded in paraffin, again frozen, and sectioned using the markers as reference points. On T1-weighted images, synovial fluid had low signal intensity (dark) compared to the infrapatellar fat pad which had a high signal intensity (bright). Articular cartilage was visualized as an intermediate bright signal and was separated from trabecular bone by a dark line representing subchondral bone. Menisci, fibrous joint capsule, and ligamentous structures appeared dark. In the true sagittal plane, the entire caudal cruciate ligament was often seen within one image slice. The patella was visualized as an intermediate bright signal (trabecular bone) surrounded by a low intensity signal (cortical bone). The trochlea and the intercondylar notch were difficult areas to analyze due to signal volume averaging of the curved surface of these areas and the presence of several types of tissues.