Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis.

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Cyclic voltammetry and impedance spectroscopy were employed to probe the responsive properties of polyelectrolyte brushes. Poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes over 100 nm thick on gold substrates were synthesized via surface-initiated atom-transfer radical polymerization and quaternized with methane iodide to obtain cationic brushes (Q-PDMAEMA). Q-PDMAEMA brushes respond to electrolytes by exhibiting swollen and collapsed states. Swollen brushes allow good permeability of electroactive probes, while collapsed states block electron transport. Electrolytes have different impacts on the electrochemical properties of Q-PDMAEMA. Some salts (NaNO3) cause brush collapse due to charge screening, while others such as those with more hydrophobic anions (ClO4-, PF6-, and Tf2N-) induce brush collapse because of solubility changes. The collapsed brushes exhibit intrinsically different resistance as probed with impedance. Charged screened brushes retain good permeability to electroactive probes. Strongly coordinating hydrophobic anions lead to insoluble brushes, resulting in a high resistance. These results show that electrochemical impedance spectroscopy is a powerful technique to probe the properties and structure of polyelectrolyte brushes.

In this paper, a novel strategy was reported to produce ternary nanocomposite containing TiO 2 nanowires, poly [(dimethylamino)ethyl methacrylate] (PDMAEMA) brush and Pd nanoparticles. PDMAEMA brushes were grafted from catecholic initiator anchored on TiO 2 nanowires via surface-initiated atom transfer radical polymerization (SI-ATRP) at ambient conditions. The PDMAEMA uniformly covered the surface of TiO 2 nanowires and the two component of PDMAEMA and TiO 2 shows clear boundary interface. PDMAEMA brushes were derived with CH 3 I to form quaternized-PDMAEMA (Q-PDMAEMA) so as to facilitate anion exchange with PdCl 4 2-, which was followed by in situ reduction with NaBH 4 to obtain the TiO 2 nanowires-Q-PDMAEMA/Pd(0) ternary nanocomposite. Pd nanoparticles have very small size of about 2-4nm and monodisperse, uniformly distributed among polymer brush network. Interestingly, after reduction reaction, concurrent with generation of Pd nanoparticles, the ammonium cations were largely recovered, which allows further breath-in PdCl 4 2counterions and uploads more Pd nanopaticles by repeated steps. The responsivity of both PDMAEMA and Q-PDMAEMA decorated TiO 2 nanowires was studied in response to pH and salt solution. The electrocatalytic behavior of the ternary nanocomposite was investigated.

Summary Abscission is a process in which plants shed their parts, and is mediated by a particular set of cells, the abscission zone (AZ). In grasses (Poaceae), the position of the AZ differs among species, raising the question of whether its anatomical structure and genetic control are conserved. The ancestral position of the AZ was reconstructed. A combination of light microscopy, transmission electron microscopy, RNA‐Seq analyses and RNA in situ hybridisation were used to compare three species, two (weedy rice and Brachypodium distachyon) with the AZ in the ancestral position and one (Setaria viridis) with the AZ in a derived position below a cluster of flowers (spikelet). Rice and Brachypodium are more similar anatomically than Setaria. However, the cell wall properties and the transcriptome of rice and Brachypodium are no more similar to each other than either is to Setaria. The set of genes expressed in the studied tissues is generally conserved across species, but the precise developmental and positional patterns of expression and gene networks are almost entirely different. Transcriptional regulation of AZ development appears to be extensively rewired among the three species, leading to distinct anatomical and morphological outcomes.

An in-situ polymerization to coat fabrics with polydopamine-encapsulated octadecylamine endows the fabrics with self-cleaning and self-healing abilities. The treated fabric exhibits self-healing after losing its hydrophobicity. It is durable against washing and mechanical abrasion without changing the hydrophobicity. Thanks to the versatile adhesive property of polydopamine, the approach is compatibile with a variety of substrates, such as fabrics, glass, sponge, paper, and polymeric materials.

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Grafting zwitterionic polymer brushes via electrochemically mediated-surface initiated atom transfer radical polymerization for anti-bacterial and anti-fouling applications.