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The development of new magnetic materials for applications such as magnetic-driven drug delivery, next-generation display materials, and magnetic resonance imaging is an important objective. To that end, we synthesized monodispersed, magnetically responsive particles grafted with well-defined polymer brushes and investigated the formation of their ordered arrays in organic solvents in response to a magnetic field. To achieve this, we prepared monodispersed magnetic nanoparticle clusters (MNCs) composed of large numbers of superparamagnetic ferrite ZnFe2O4nanoparticles. The MNCs were subsequently coated with thin silica layers through the hydrolysis of tetraethoxysilane. The colloidal particles were surface-modified with initiating groups for atom transfer radical polymerization (ATRP) using a triethoxysilane derivative with an ATRP initiation site. To demonstrate the ability of the synthesized particles to produce well-defined polymer brushes on their surfaces, the ATRP-initiator-functionalized silica-coated MNCs were subjected to surface-initiated ATRP with methyl methacrylate. This polymerization proceeded in a living fashion to produce graft polymers with targeted molar masses and narrow molar mass distributions. The average graft density was determined to be 0.65 chains/nm2, which confirms the formation of concentrated polymer brushes on the MNCs. The hybrid particles were analyzed by dynamic light scattering and transmission electron microscopy techniques, which revealed excellent uniformity and solvent dispersibility. A suspension of the polymer-brush-decorated MNCs in acetone quickly developed intense structural color in response to approaching a magnet that depended on the strength of the magnetic field.

Background The efficacy of a direct-acting antiviral agent (DAA) is compromised by the development of drug resistance. The associations between resistance-associated virus (RAV) and therapeutic outcomes have not been well-understood.Methods A total of 30 patients with HCV genotype-1b were enrolled and treated for 24 weeks with asunaprevir (ASV) and daclatasvir (DCV). Viral sequences in non-structural (NS) regions 3 and 5A in serum and liver tissue before treatment were examined with direct sequencing, next-generation sequencing (NGS) and the PCR-invader method to evaluate the importance of drug-resistance in the prediction of the outcomes of ASV plus DCV therapy.Results Of 30 patients (22 treatment-naive patients, 2 interferon-intolerant patients and 6 non-responders), 25 patients (83.3%) achieved sustained virological response (SVR) 24 weeks after the treatment. Viral breakthrough occurred in three treatment-naive patients and one non-responder. One treatment-naive patient experienced viral relapse. Among 25 patients without RAV, 24 obtained SVR, whereas 5 patients had RAV with a 1.3 to 88% frequency, resulting in various therapeutic outcomes. As for HCV compartments, similar RAVs were detected in serum and liver tissue for a patient obtaining SVR despite HCV NS5A Y93H and another developed viral breakthrough although no RAV was detected. Direct sequencing could not detect RAVs in low frequency (1.3 to 12%) for three of four patients.Conclusions Low frequency of RAVs might not affect the outcomes of ASV plus DCV therapy. Deep sequencing and PCR-invader methods can detect clinically significant RAVs for ASV plus DCV therapy.

Since copying span has been said to reflect text difficulty, copying span may reflect learners' written language ability when text is held constant. The present study investigated this hypothesis, using as subjects 43 adult women who were learning English as a second language. Analysis showed that copying span moderately correlates with reading, dictation, and spelling ability. Individual differences in imbalance between reading and writing abilities seem to lower the magnitude of the correlation. An optimal text in terms of difficulty and length for the copying task is needed and remains an important matter for further research.

Abstract: Corelike structures, which were interpreted as straight, large cylinders containing ribosome-like particles surrounded by an amorphous substance of low electron density, were found in a stable L-form ofStreptococcus pyogenes grown in the absence of antibiotics.

Ultrastructure of an unstable L-form strain P42L induced from Proteus mirabilis was demonstrated. The L-form grown in L-form media was composed of large cells and small vesicular structures. The L-form cell was spherical in shape measuring 2μm to 10μm in diameter and bounded by a cell wall which was thinner and somewhat damaged. In some cell, whorl-like membrane structures composing of a unit membrane arranged in several or more layers and small vesicular ones were found in the cytoplasm. The extracellular vesicular structures bounded by a triple-layered membrane, which measured 35 nm in diameter and seemed to be originated from outer membrane of the L-form cells, were also observed around the large cells. It is suggested that the unstable L-form is able to synthesize its cell wall components, but has not potentiality to build up completely into a cell wall structure.