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A nonequilibrium periodic structure is induced by a magnetic field H applied to an aligned lyotropic uniaxial nematic phase of disodium cromoglycate–water. A series of parallel lines perpendicular to H represents boundaries between 180° out-of-phase regions of director reorientation. The distance between the lines decreases with increasing H. The line spacing is also directly proportional to thickness of the sample (in a limited range of thickness), and a secondary periodicity, consisting of nodes in these lines, is observed in thicker samples. An extension of a theoretical model by Guyon et al. is used to qualitatively interpret the abovementioned dependencies. [ABSTRACT FROM AUTHOR]

Two hundred and forty-four clinical and environmental strains of nine species of halophilic vibrios isolated in Hong Kong were tested for their susceptibilities to 23 antimicrobial agents by an agar dilution method using unsupplemented Mueller-Hinton agar, an inoculum size of 10(5) cfu per spot and incubation for 18 h at 30 degrees C. Most strains were resistant to sulphamethoxazole, trimethoprim, penicillins and older cephalosporins, and most were susceptible to chloramphenicol, tetracycline, cotrimoxazole, the aminoglycosides, the newer cephalosporins, aztreonam, imipenem and the quinolones. However, there were significant differences between species, especially in their patterns of beta-lactam susceptibility. [ABSTRACT FROM AUTHOR]

Two hundred and sixty-six non-replicate Hong Kong isolates of methicillin-resistant Staphylococcus aureus were tested for their susceptibility to various anti-staphylococcal agents. Multiple resistance was common. More than 95% of patient isolates were resistant to both gentamicin and tetracycline, 68% to erythromycin, 37% to chloramphenicol, 10% to trimethoprim, 5% to rifampicin and 2% to fusidic acid. No isolate was resistant to all these agents, but nineteen different patterns of resistance were identified. Selected gentamicin-resistant isolates were tested against other aminoglycosides, and were sensitive to amikacin and netilmicin. The pattern of aminoglycoside resistance indicated that all isolates produced the aminoglycoside-modifying enzymes APH-(2") and AAC-(6')-I. All isolates were sensitive to vancomycin and teicoplanin. A single strain was resistant to three of the five quinolones tested, but resistance to all the quinolones could be induced easily in vitro by exposure to increasing subinhibitory concentrations of norfloxacin in broth. [ABSTRACT FROM AUTHOR]

Four-hundred and seventy-six isolates of Staphylococcus aureus from patients in Hong Kong were tested for methicillin-resistance by agar dilution and disc diffusion methods, using heavy inocula. With Mueller-Hinton agar incubated at 30 degrees C for 24 h, 216 (MRSA) isolates were resistant to 8 mg/l of methicillin and grew up to the edge of a 10 micrograms methicillin disc, and 260 strains were susceptible to greater than or equal to 4 mg/l methicillin and produced inhibition zones of at least 20 mm diameter. Incubation for 48 h, the addition of sodium chloride, or the use of a 5 micrograms disc had little effect on these results, but a significant number of MRSA strains produced inhibition zones when disc diffusion tests were incubated at 35 degrees C, and many sensitive strains showed scanty growth on salt-containing agar at high methicillin concentrations in agar dilution tests. Iso-Sensitest agar did not appear to support the growth of the minority resistant populations of MRSA unless supplemented with menadione and thiamine, and even with supplemented Iso-Sensitest medium a few presumptively resistant strains appeared methicillin-sensitive in both disc diffusion and agar dilution tests. [ABSTRACT FROM AUTHOR]

The Microbact 24E (MB24E) system is a commercial microsystem for the identification of common clinical isolates of Enterobacteriaceae and non-fermenting Gram negative bacilli, and consists of dehydrated substrates distributed in the wells of microtitre trays. This system was compared with the API20E for the identification of 386 bacterial isolates, which included 284 clinical and 102 environmental organisms. There was 97% and 91% agreement for the identification of clinical isolates of Enterobacteriaceae and other Gram negative bacilli, respectively. The identification of environmental isolates by both systems was less satisfactory. The API20E has a more extensive database than the MB24E and is thus more reliable for the identification of rare or unusual organisms, but the MB24E is cheaper, is easy and convenient to use, and is suitable for a routine microbiology laboratory. [ABSTRACT FROM PUBLISHER]

The high-temperature structure of solvent-free C(70) has been determined with high-resolution x-ray powder difraction and electron microscopy. Samples crystallized from solution form hexagonal close-packed crystals that retain an appreciable amount of residual toluene, even after prolonged heating. Samples prepared by sublimation, which contain no detectable solvent, are primarily face-centered cubic with some admixture of a hexagonal phase. The relative volume of the hexagonal phase can be further reduced by annealing. The structures of both phases are described by a model of complete orientational disorder. The cubic phase contains an appreciable density of stacking faults along the [111] direction.

Phage HK139 is UV inducible and lambda homoimmune and has the host range of phi80. It can recombine with lambda as well as with phi80, and in the prophage form it is found integrated between the loci his and supD.