Mobile catabolic genes in bacteria

The recent findings of various mobile catabolic genes have provided some insight into the evolution of microbial degradation systems for xenobiotic compounds. The catabolic genes undergo marked genetic rearrangements due to their presence on transposons or association with mobile genetic elements. Bacterial catabolic transposons fall into three defined structural classes. Class I elements include catabolic genes flanked by two copies of insertion sequences. Class II elements carry short terminal inverted repeats and transpose by the replicative mode in which transposase and resolvase are involved. Conjugative catabolic transposons represent the third class of mobile genetic elements. They carry all the genes required for excision, conjugal transfer to a new host, and integration. This review focuses on the structures, functions and roles of the recently characterized catabolic transposons in bacteria. Also described are the mobile catabolic elements that share structural similarity with the pathogenicity and symbiosis islands.     

A novel spectroelectrochemical cell for in situ surface X-ray scattering measurements of single crystal disk electrodes

A newly designed spectroelectrochemical cell was constructed for surface X-ray scattering (SXS) to study single crystal electrodes. Electrochemical characteristics of a specific face of a single crystal electrode can be investigated in the meniscus mode, and SXS measurement can be easily carried out using the spectroelectrochemical cell. The usefulness of the present cell was demonstrated by studying the electrochemical deposition of thin Pd layers on Au(111) and Au(100) that require precise amounts of Pd deposits.     

Nowhere-differentiable attractors

The notion of nowhere-differentiable attractors is illustrated with four prototype equations, that is, maps of invertible type. Four classes of nowhere-differentiable attractors can be distinguished so far: the (nongeneric) continuous-nonchaotic-nonfractal type; the (nongeneric) continuous-fractal type; the (generic) singular-continuous-fractal type; and the (generic) continuous-fractal-in-a-projection type. the history of all four classes is linked with the name of J. A. Yorke in different ways. Even though continuous fractal nowhere-differentiable attractors do not exist genetically, the hypothesis that the fractal geometry of nature may be a consequence of the fact that nature is a differentiable dynamical system is strengthened. Attractors with nowhere-differentiable generic projections can mimic the whole richness of fractal pictures. © 1995 John Wiley & Sons, Inc.     

Reference values for bisphosphoglycerate mutase protein content and specific activity in human erythrocytes

Cytomegalovirus (CMV) gastritis has been reported in transplant patients. Symptoms are considered nonspecific, and gastroscopy with biopsy is usually performed to establish the diagnosis. Three patients are described here 1 to 3 months after solid organ transplantation, with primary CMV gastritis, confirmed by gastroscopy, histopathologic examination and cultures. The clinical presentation in all three cases was sharp epigastric pain that decreased in a supine position, increased while sitting and further increased when standing or walking. The epigastric pain completely resolved after treatment with ganciclovir. To the best of our knowledge, such postural epigastric pain has not been described as a specific symptom in any other clinical entity and may be a unique sign of primary CMV gastritis.     

Osteoclastogenesis inhibitory factor exhibits hypocalcemic effects in normal mice and in hypercalcemic nude mice carrying tumors associated with humoral hypercalcemia of malignancy

In the present study, we attempted to determine the extent to which an anterior capsulorrhexis carried out during cataract surgery contracts postoperatively. The size of the continuous curvilinear capsulorrhexis (CCC) was measured at the end of surgery and at the final follow-up examination in 52 eyes of 40 patients who underwent phacoemulsification/aspiration and implantation of an intraocular lens (IOL) with 6-mm optics. Images obtained by video during surgery and by slit-lamp microscopy were used to determine the CCC size with reference to the optics of the IOL. The average CCC size was 5.0 mm at the end of surgery; it contracted to 4.4 mm by the final postoperative examination. The contraction of the anterior capsule progressed rapidly in the first 50 days following surgery and then gradually thereafter. The extent of contraction was greater in older patients. The smaller the CCC size immediately after surgery, the more rapidly it contracted. The size of the capsulorrhexis contracted an average of 22% following cataract surgery. The contraction rate tended to be higher in older patients. The results suggest that the capsulorrhexis carried out in cataract surgery for elderly patients should be sufficiently large, but not larger than the optics size of the IOL.     

Polymerization of organic compounds in an electrodeless glow discharge. XI. Pressure in glow discharge

The pressure of a steady-state flow of monomer, p₀, changes to a new steady-state flow pressure, p_g, in glow discharge. The value of p_g is dependent on the flow rate of monomer, the pumping-out rate of the vacuum system for the product gas (which is hydrogen in many cases of plasma polymerization of hydrocarbons), and the characteristic hydrogen yield of a monomer associated with plasma polymerization. The relationships between these factors were established and examined for plasma polymerizations of acetylene, ethylene, and acrylonitrile.     

Liquid crystalline polyethers based on conformational isomerism

Summary The synthesis and determination of virtual mesomorphic phase transitions of the polyether based on l-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl) ethane (MBPE) and 1,14-dibromotetradecane (MBPE-14) and of the copolyethers based on MBPE and 1,14-dibromotetradecane with 1,5-dibromopentane (MBPE-5/14), 1,8-dibromooctane (MBPE-8/14) and 1,9-dibromononane (MBPE-9/14) are presented. The homopolymer MBPE-14 is only crystalline, while the copolymers display a monotropic (MBPE-5/14 and MBPE-9/14) or even an enantiotropic (MBPE-8/14) nematic mesophase. The averaged virtual isotropicnematic transition temperature of MBPE-14 determined from these copolymers is 87 ± 7 °C (H=2.77±0.21 kcal/mru).