CO2-Triggered and temperature-switchable crystallization-driven self-assembly of a semicrystalline block copolymer in aqueous medium

The synthesis of a semicrystalline block copolymer comprising a hydrophilic poly(acrylic acid) pure block and an amphiphilic poly(acrylic acid)-r-poly(octadecyl acrylate) random block by nitroxide-mediated polymerization is reported.

Bilingualism confers advantages in task switching: Evidence from the dimensional change card sort task

We examined the influence of bilingualism on task switching by inspecting various markers for task-switching costs. English monolinguals and Korean–English bilinguals completed a modified Dimensional Change Card Sort task based on a nonverbal task-switching paradigm. We found advantages for Korean–English bilinguals in terms of smaller single-task (pure-block) switch costs and greater reactivation benefits than those of English monolinguals. However, bilingual advantages in mixing costs were relatively weak, and the two groups did not differ on local switch costs. Notably, when we approximated the cue-based priming effect in single-task (pure) blocks, we found no evidence that the locus of bilingual advantages in task-switching performance is attributable to a basic cue-priming effect. Taken together, our results suggest that bilingualism is conducive to task switching via facilitation in control processing, including inhibition of proactive interferences and efficient adaptation to abstract task-set reactivation.

CHARACTERISTICS OF ANTIBIOTIC RESISTANCE OF BACTERIA ISOLATED FROM INFANTS – PATIENTS OF NATIONAL HOSPITAL PEDIATRICS HANOI, VIETNAM

The results of studies of resistance to antibiotics microflora isolated from mucous pharynx and rectum of patients intensive care unit newborns of National Hospital of Pediatrics, Hanoi are presented. It is shown that gram-negative bacteria isolated from children have a high resistance to penicillins, cephalosporins and carbapenem. Antibiotic resistance of bacteria isolated from children receiving treatment in «pure» block did not differ from sustainability of the strains, selected from children in «dirty» block.

Pollen Flow and the Effect on Fruit Size in an 'Imperial' Mandarin Orchard

Pollen source is known to affect the fruit size and quality of 'Imperial' mandarin, but no study has determined the appropriate orchard design to maximize the beneficial effects of pollen source. We determined the parentage of seeds of 'Imperial' mandarin using the isozyme shikimate dehydrogenase to characterize pollen flow and the effect on fruit size in an orchard setting. Two blocks were examined: 1) a block near an 'Ellendale' pollinizer block; and 2) an isolated pure block planting. Fruit size and seed number were maximum at one and three rows from the pollinizer (P ≤ 0.05). Isozyme results were consistent with all seeds being the result of fertilization by the 'Ellendale' pollinizer. In the pure block planting, fruits in rows 5-11 inside the block were very small with no seeds. This indicates poor pollen flow resulting in a reduction in fruit quality for the pure block. These results emphasize the importance of pollinizers in orchard design, and bees in orchard management. They suggest that each row should be planted no more than three rows from the pollinizer to maximize the benefits of the pollen parent in self-incompatible cultivars such as 'Imperial'.

Sequence Distribution of Commercial SBR by Ozonolysis-GPC Measurement

Sequence distribution of commercially obtained styrene-butadiene copolymers (SBR) was investigated by high-resolution-GPC measurement of ozonolysis products. The ozonolysis-GPC of emulsion SBR samples showed peaks corresponding to 1 to 4 styrene sequences and styrene-1,2-butadiene sequences flanked by 1,4-butadiene units. In random SBR samples with anionic polymerization, long styrene sequences of from 8 to 19% were detected in addition to the short styrene sequences. So-called tapered-block structure was clearly observed in partially block SBR samples; a broad peak derived from block styrene sequences in a relative intensity of 49 to 55% was overlapped by peaks due to styrene sequences longer than 10 styrene units. The content of pure-block styrene sequences in S-B-S type triblock SBR samples was found to be 85 to 99% or above.