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Electric double-layer field effect experiments were performed on ultrathin films of La0.325Pr0.3Ca0.375MnO3, which is noted for its micrometer-scale phase separation. A clear change of resistance up to 220% was observed and the characteristic metal—insulator transition temperature TP was also shifted. The changes of both the resistance and TP suggest that the electric field induced not only tuning of the carrier density but also rebalancing of the phase separation states. The change of the charge-ordered insulating phase fraction was estimated to be temperature dependent, and a maximum of 16% was achieved in the phase separation regime. This tuning effect was partially irreversible, which might be due to an oxygen vacancy migration that is driven by the huge applied electric field. [ABSTRACT FROM AUTHOR]

Background:The association of PMQR and ESBLs in negative-bacteria isolates has been of great concern. The present study was performed to investigate the prevalence of co-transferability of oqxAB and blaCTX-M genes among the 696 Escherichia coli (E. coli) isolates from food-producing animals in South China, and to characterize these plasmids. Methods:The ESBL-encoding genes (blaCTX-M, blaTEM and blaSHV), and PMQR (qnrA, qnrB, qnrS, qnrC, qnrD, aac(6’)-Ib-cr, qepA, and oqxAB) of these 696 isolates were determined by PCR and sequenced directionally. Conjugation, S1 nuclease pulsed-field gel electrophoresis (PFGE) and Southern blotting experiments were performed to investigate the co-transferability and location of oqxAB and blaCTX-M. The EcoRI digestion profiles of the plasmids with oqxAB-blaCTX-M were also analyzed. The clonal relatedness was investigated by PFGE. Results:Of the 696 isolates, 429 harbored at least one PMQR gene, with oqxAB (328) being the most common type; 191 carried blaCTX-M, with blaCTX-M-14 the most common. We observed a significant higher prevalence of blaCTX-M among the oqxAB-positive isolates (38.7%) than that (17.4%) in the oqxAB-negative isolates. Co-transferability of oqxAB and blaCTX-M was found in 18 of the 127 isolates carrying oqxAB-blaCTX-M. These two genes were located on the same plasmid in all the 18 isolates, with floR being on these plasmids in 13 isolates. The co-dissemination of these genes was mainly mediated by F33:A-: B- and HI2 plasmids with highly similar EcoRI digestion profiles. Diverse PFGE patterns indicated the high prevalence of oqxAB was not caused by clonal dissemination. Conclusion:blaCTX-M was highly prevalent among the oqxAB-positive isolates. The co-dissemination of oqxAB-blaCTX-M genes in E. coli isolates from food-producing animals is mediated mainly by similar F33:A-: B- and HI2 plasmids. This is the first report of the co-existence of oqxAB, blaCTX-M, and floR on the same plasmids in E. coli. [ABSTRACT FROM AUTHOR]

A concept is demonstrated to controllably form unipolar resistive filaments in pristine insulating oxides by a low-energy H+ irradiation via the ion bombarding effect and reactions in the oxides. In contrast to the conventional electroforming process in an uncontrollable way, our method well controls the density and distribution range of the switching filaments and largely reduces the probability of random occurrence of conducting channels. The memory devices prepared with our method are free of initial electroforming process and exhibit good switching performances. The ion irradiation proved an effective method to improve the performance of resistance random access memories. [ABSTRACT FROM AUTHOR]

Summary: Objective: To evaluate the mass measles vaccination campaign of 2009 in Guangdong Province, China. Methods: Data on the campaign implementation, measles surveillance, and serological surveillance were reviewed and analyzed by statistical methods. Results: Rapid coverage surveys showed that 98.09% of children were vaccinated during the campaign. The coverage of migrant children increased significantly from 67.10% to 97.32% (p <0.01). From May to December 2009, after the campaign, the number of measles cases was reduced by 93.04% compared with the same period of 2008. The antibody positive rate in children aged less than 15 years reached above 95%. More than 1 million migrant children were identified and vaccinated during the campaign. Flyers, notices of information from doctors, and television programs were the best methods to inform parents of the campaign. Awareness of the campaign by residents increased significantly from 91.86% to 97.10% (p <0.01) through the use of social mobilization materials. Conclusions: A massive vaccination campaign approach for controlling measles in a developing region like Guangdong Province with a vast migrant population has proved effective. Comprehensive mobilization, communication with the mass media, and support from government departments were critical to the success of the campaign. [Copyright &y& Elsevier]