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One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age-standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are affecting the number of adults with diabetes.

La réactivité et la structure d'un catalyseur de post-combustion automobile ont été étudiées et caracterisées in situ par EXAFS sous des mélanges gazeux dont la composition oscillait. Il a été montré qu'il existe un phénomène de désactivation transitoire durant l'excursion oxydante qui est dû au fait que dans le rhodium forme l'oxyde de rhodium Rh2O3inactif. Par ailleurs, le platine n'est pas affecté et reste à l'état réduit maintenant ainsi l'activité en milieu oxydant.

The operation of an alumina supported PtRh three-way catalysts has been studied under oscillating gas mixtures. An XAS study of the catalyst has shown that under oxidising conditions the inactive Rh2O3forms is rereduced upon exposure to a reducing gas mixture. The Pt, on the other hand, has been shown to remain reduced even under an oxidising environment.

During experiments designed to simulate the oscillations of composition observed upon the catalyst in a vehicle exhaust device, a Pt-Rh bimetallic catalyst supported on alumina was studied for three-way catalytic reactions under both stationary and cycling conditions, The results were compared with those obtained from employing platinum or rhodium metals supported separately upon alumina and indicated that during the operation of the oscillatory regime on the bimetallic catalyst there is a deactivation/activation mode associated with a fast redox process of the rhodium component which becomes partially oxidised to its inactive form, Rh₂O₃. Deactivation was not observed with platinum alone nor under steady feed conditions in the bimetallic case. The effect of this cycling deactivation is examined with respect to the temperature required to affect the bulk of the metals, its consequential reorganisation of the surface, and subsequent interaction with the oxygen.Copyright 1995, 1999 Academic Press, Inc.

We have identified genes from Streptomyces levoris A-9 involved in the biosynthesis of the peptide antibiotic valinomycin. Two segments of chromosomal DNA were recovered from genomic libraries, constructed by using the low-copy-number plasmid pIJ922, by complementation of valinomycin-deficient (vlm) mutants of S. levoris A-9. One set of plasmids restored valinomycin production to only one mutant, that carrying vlm-1, whereas a second set of plasmids restored productivity to seven vlm mutants, those carrying vlm-2 through vlm-8. Additional complementation studies using subcloned restriction enzyme fragments showed that the vlm-1+ gene was contained within a 2.5-kilobase (kb) DNA region, whereas alleles vlm-2+ through vlm-8+ were contained in a 12-kb region, representing at least three genes. Physical mapping experiments based on the isolation of cosmid clones showed that the two vlm loci were 50 to 70 kb apart. Southern hybridization experiments demonstrated that the vlm-2+ gene cluster was highly conserved among other valinomycin-producing Streptomyces strains, whereas the vlm-1+ gene was ubiquitous among Streptomyces species tested. Increasing the copy number of the vlm-2+ gene cluster in S. levoris A-9 by the introduction of low-copy-number recombinant plasmids resulted in a concomitant increase in the level of valinomycin production.

In a preliminary experiment a single treatment of 2 kg ha-1 glyphosate was found to be as effective as higher rates of application in reducing Cyperus rotundus shoot numbers. Single applications of 11-2 kg ha-1 bromacil and 976 kg ha-1 methyl bromide were compared with multiple applications of 2 kg ha-1glyphosate, 4.5 kg ha-1 2,4-D, 4 kg ha-1 EPTC, 2.4 kg ha-1 vernolate, 5 kg ha-1 pebulate, 2-9 kg ha-1 amitrole and eight successive rotary hoeings during dry weather, all over a 19-month period. Most treatments reduced shoot and tuber populations and tuber weights but the most efficient treatments were bromacil, cultivation, glyphosate and 2,4-D. At the end of the experiment the percentage of tubers with shoots was similar for many treatments but was higher on the thiocarbamate treatments and tended to be lower on the glyphosate treatment. The percentage of dormant or moribund tubers was higher on the glyphosate treatment than on other treatments. The greatest effect of most treatments was on the shallowest tubers (0-10 cm), except for 2,4-D which affected tubers uniformly over the three depth ranges studied.

Escherichia coli strains with mutations rho-115, rho-ts15, rho-101 (psu-1) or rho-102 (psu-2) are more sensitive (“supersensitive”) to rifampicin than isogenic parent strains, as measured by growth rate in broth and colony forming efficiency on solid media with 5, 10, or 20 µg of rifampicin per ml. There is no change in sensitivity of rho mutants to the antibiotics penicillin, erythromycin, chloramphenicol, or the detergent desoxycholate. The rho-101 or rho-102 mutations confer rifampicin supersensitivity at 32°C but not 42°C. Mutants of a rho-115 strain that have lost polarity suppression can be isolated by selection for rifampicin resistance. This phenotype, Sur, is not due to reversion of the original rho gene mutation but to a second mutation perhaps in the gene for rho protein or the gene for the ß subunit of RNA polymerase. One class of Sur mutation, occurring in rho-115 cells isolated as resistant to 20 µg of rifampicin per ml, is co-transducible with the marker ilv, and the gene order is rbs-ilv-sur-38. A model suggested by this map position is that the mutations rho-115 and sur-38 define the domain of rho protein which interacts with the ß subunit of RNA polymerase.

Rho has been purified to homogeneity from Escherichia coli double mutant rho-115 sur-38 cells, and from rho++ and rho-115 cells. The sur-38 mutation suppresses the original rho-115 phenotype. We observe that the polyC-dependent ATPases of these three rho preparations have the same specific activities. However, the ATPase of rho from the double rho-115 sur-38 mutant is extremely heat labile, while that from rho-115 shows a heat lability intermediate between the wild type and the double mutant.

Hierarchical agglomerative polythetic clustering of vegetation data for 51 sites from Brian Pastures Research Station, south-east Queensland, Australia, produced site and species groups that supported those formed during a previous intuitive mapping survey. On the basis of floristic composition, these analyses suggested the possible amalgamation of some map units. However, their segregation into separate units was justified on the basis of having distinct photopatterns and physiographic positions in the landscape. The classifications of the trees only (55 species) and woody plants only (115 species) data sets produced site groupings of high similarity to those constructed by the mapping survey. The addition of the herbaceous plants (266 additional species, of which 70% were annual species) tended to dominate the analyses, and produce site groupings that were less similar to the mapping groups. The distribution of many annual species appeared to be independent of the perennial plant species and underlying substrate. In wooded communities, herbaceous plants have only a minor influence on photopattern, which is the primary determinant of the mapping classification. Binary data retained a large percentage of the information contained in the quantitative data. The extra effort of gathering herbaceous data may not be justified for a broad scale mapping project, but is required for comprehensive nature conservation surveys, flora inventory, and vegetation monitoring purposes.

Department of Physiology, Queen's University, Kingston, Ontario, Canada(Received11 November1974)Gonadal steroids in the circulation are thought to act on adenohypophysial luteinizing hormone (LH) and hypothalamic LH releasing hormone (LH-RH) to reduce their secretion. The data on which this concept is based were obtained with relatively insensitive bioassay methods (Piacsek & Meites, 1966). Contrary to expectation, we found that both serum and hypothalamic LH-RH had fallen 3 weeks after castration (Shin, Howitt & Milligan, 1974). This is not consistent with the conventional feedback concept of hypothalamic LH-RH, but has recently received confirmation (Eskay, Oliver, Grollman & Porter, 1974; Ferland, Coté & Labrie, 1974).To clarify better our understanding of the factors that influence LH-RH secretion, the time course of changes in LH and LH-RH after castration have been examined in more detail.Male Sprague–Dawley rats were handled as described previously (Shin et al.1974). Hypothalami were extracted according

Department of Physiology, Queen's University, Kingston, Ontario, Canada K7L 3N6(Received20 May1974)It is well established that gonadal steroid hormones stimulate prolactin secretion and increase the level of prolactin in the blood (Meites, Lu, Wuttke, Welsch, Nagasawa & Quadri, 1972). Many studies of the factors affecting the level of prolactin in the blood have been performed with anaesthetized rats (Chen & Meites, 1970; Wuttke & Meites, 1970; Kalra, Fawcett, Krulich & McCann, 1973). However, since it is now reasonably well established that anaesthetic agents can change levels of prolactin in the circulation (Wakabayashi, Arimura & Schally, 1971; Ajika, Kalra, Fawcett, Krulich & McCann, 1972; Terkel, Blake & Sawyer, 1972), we decided to re-examine the effect of gonadal steroids upon plasma levels of prolactin in the unanaesthetized rat. Animals were castrated and prolactin levels were determined at three intervals with and without the administration of testosterone.Young male rats

Behavioral responses of Tribolium castaneum (Herbst) and Sitophilus oryzae L. to fenitrothion and of Rhyzopertha dominica L. to carbaryl and to bioresmethrin were tested by adding eggs (S. oryzae or R. dominica) or pupae (T. castaneum) to wheat unsprayed or sprayed with insecticide. Grain containing insects was placed above or below another layer of sprayed or unsprayed wheat so that insects could move freely between layers. The recommended application rate commonly used in Australia and a sublethal dosage of insecticide were tested. Numbers of live and dead adults and emigrants were counted. Carbaryl and fenitrothion did not affect insect movement, whereas bioresmethrin repelled R. dominica at concentrations of 0.25 and 1.0 mg/kg grain. Results indicated that, because of its repellent effect, less R. dominica than expected will be exposed to bioresmethrin. These results have implications for insecticide bioassay, population modeling, and in studies of the development of resistance.