Modelling the effect of the antimicrobial tylosin on the performance of an anaerobic sequencing batch reactor.

A laboratory-scale anaerobic sequencing batch reactor (ASBR) was fed a synthetic wastewater containing glucose to study the effects of the antimicrobial tylosin on treatment performance. Measurements of methane, volatile fatty acids, and COD concentrations suggested that the addition of 1.67 mg/L and 167 mg/l of tylosin to the synthetic wastewater inhibited propionate oxidizing syntrophic bacteria and aceticlastic methanogens. The latter is presumed to be an indirect effect. A modified version of the IWA Anaerobic Digestion Model No. 1 (ADM1) with extensions for microbial storage and hydrolysis of reserve carbohydrates, and tylosin liquid-solid mass transfer and inhibition adequately described the dynamic profiles observed in the ASBR.     

An EDTA-associated anti-B agglutinin: the role of ionized calcium

BACKGROUND: It is believed that EDTA-dependent panagglutination is associated with free carboxylic acids that support reactions of rare autoagglutinins. CASE REPORT: An ABO typing discrepancy occurred in an 88-year-old patient. The specificity of his autoagglutinin was demonstrated by panel cell study and absorption tests using normal donors' red cells or immunoadsorbents coated with A, B, or O substances. Inhibition assays were performed to determine whether the autoagglutinin was inhibited by ionized calcium or carboxylic acids. The autoagglutinin had anti-B specificity when tested in the presence of EDTA. It was neutralized by group B secretor saliva and adsorbed by crystalline silica coated with simple B substances with or without EDTA, although it was absorbed by group B red cells only in the presence of EDTA. The agglutinating activity was stronger at 25 degrees C (titer 64) than at 37 degrees C (titer 16) and was destroyed by treatment of the serum with dithiothreitol, which suggests that the autoagglutinin is IgM. This activity also appeared in the patient's serum after dialysis and in an eluate obtained after adsorption with simple B substances, and it was inhibited by the addition of CaCl2 at 0.5 mM or higher concentrations. This suggests that the agglutination is not dependent on EDTA but, rather, on the concentration of ionized calcium. The autoagglutinin failed to react with group B red cells treated with glutaraldehyde for 10 minutes. CONCLUSION: An anti-B autoagglutinin was shown to have caused an ABO typing discrepancy in the presence of EDTA. These results suggest that autoagglutination requires an environment with low levels of ionized calcium, but not the presence of carboxyl groups.     

Initial permeability of amorphous single and multilayered films

Initial permeabilities of Co-Zr-Nb amorphous single and multilayered films were measured in the frequency range 1-250 MHz. The results are correlated to those of anisotropy dispersion measurements. The multilayered films are relatively free from demagnetizing effects, which leads to good frequency characteristics of the permeability.     

Finite Larmor radius effects on ripple diffusion in tokamaks

The confinement of alpha particle is important in tokamaks. The trajectory or confinement of alpha particles is often calculated with guiding center approximation. The features of spherical tokamak can break the approximation. We investigate finite Larmor radius effect. The orbit calculated by equation of motion is different, especially in toroidal direction, from that by guiding center equations. This difference causes difference of ripple resonance energy and the difference of the peaks of the diffusion coefficients. Furthermore, because of the additional free parameter, Larmor phase, the peaks of diffusion coefficient calculated by equation of motion are broader than those by guiding center equations.     

Orbit systematics in anisotropic Kepler problem

We revisit the Anisotropic Kepler Problem (AKP), which concerns with trajectories of an electron with anisotropic mass term in a Coulomb field. This is one of the most fundamental fields in Quantum Chaos. Nowadays various quantum systems are challenging us. Classical theories of these may have chaos. Quantum mechanics have developed from integrable cases and may have to be reformulated for such cases. AKP then serves as a suitable testing ground for quantum chaos. We first review a pioneering work by Martin Gutzwiller (J Math Phys (1977) 18:106). We shall show the systematics of the trajectories using ample figures from an extensive numerical analysis. Then we focus on the rolê of hyperbolic singularities and we comment on the approximations in an analytic formulation. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Computerized planning of cryosurgery using bubble packing: An experimental validation on a phantom material

The current study focuses on experimentally validating a planning scheme based on the so-called bubble packing method. This study is a part of an ongoing effort to develop computerized planning tools for cryosurgery, where bubble packing has been previously developed as a means to find an initial, uniform distribution of cryoprobes within a given domain; the so-called force-field analogy was then used to move cryoprobes to their optimum layout. However, due to the high quality of the cryoprobe distribution suggested by bubble packing and its low computational cost, it has been argued that a planning scheme based solely on bubble packing may be more clinically relevant. To test this argument, an experimental validation is performed on a simulated cross-section of the prostate, using gelatin solution as a phantom material, proprietary liquid nitrogen-based cryoprobes, and a cryoheater to simulate urethral warming. Experimental results are compared with numerically simulated temperature histories resulting from planning. Results indicate an average disagreement of 0.8 mm in identifying the freezing front location, which is an acceptable level of uncertainty in the context of prostate cryosurgery imaging.     

Enzymatic enrichment of arachidonic acid from Mortierella single-cell oil

An attempt was made to enrich arachidonic acid (AA) from Mortierella single-cell oil, which had an AA content of 25%. The first step involved the hydrolysis of the oil with Pseudomonas sp. lipase. A mixture of 2.5 g oil, 2.5 g water, and 4000 units (U) Pseudomonas lipase was incubated at 40°C for 40 h with stirring at 500 rpm. The hydrolysis was 90% complete after 40 h, and the resulting free fatty acids (FFA) were extracted with n-hexane (AA content, 25%; recovery of AA, 91%). The second step involved the selective esterification of the fatty acids with lauryl alcohol and Candida rugosa lipase. A mixture of 3.5 g fatty acids/lauryl alcohol (1:1, mol/mol), 1.5 g water, and 1000 U Candida lipase was incubated at 30°C for 16 h with stirring at 500 rpm. Under these conditions, 55% of the fatty acids were esterified, and the AA content in the FFA fraction was raised to 51% with a 92% yield. The long-chain saturated fatty acids in the FFA fraction were eliminated as urea adducts. This procedure raised the AA content to 63%. To further elevate the AA content, the fatty acids were esterified again in the same manner with Candida lipase. The repeated esterification raised the AA content to 75% with a recovery of 71% of its initial content.     

Fiber-optic subscriber loop systems for integrated services--The strategy for introducing fibers into the subscriber network

Two approaches to fiber-optic subscriber loop system development in Japan are described. In the first. Approach I, NTT aims at introducing inexpensive fiber-optic subscriber loop systems using conventional LED's, multimode fiber, and analog transmission techniques in the near future. In the second, Approach II, fiber-optic subscriber loop systems will be made highly functional by evolving from analog to digital transmission. This paper presents system fabrication examples for each approach and the results obtained in the tests.