We have identified a rice gene encoding a DNA-binding protein that specifically recognizes the telomeric repeat sequence TTTAGGG found in plants. This gene, which we refer to as RTBP1 (rice telomere-binding protein 1), encodes a polypeptide with a predicted molecular mass of 70 kDa. RTBP1 is ubiquitously expressed in various organs and binds DNA with two or more duplex TTTAGGG repeats. The predicted protein sequence includes a single domain at the C terminus with extensive homology to Myb-like DNA binding motif. The Myb-like domain of RTBP1 is very closely related to that of other telomere-binding proteins, including TRF1, TRF2, Taz1p, and Tbf1p, indicating that DNA-binding domains of telomere-binding proteins are well conserved among evolutionarily distant species. To obtain precise information on the sequence of the DNA binding site recognized by RTBP1, we analyzed the sequence-specific binding properties of the isolated Myb-like domain of RTBP1. The isolated Myb-like domain was capable of sequence-specific DNA binding as a homodimer. Gel retardation analysis with a series of mutated telomere probes revealed that the internal GGGTTT sequence in the two-telomere repeats is critical for binding of Myblike domain of RTBP1, which is consistent with the model of the TRF1⅐DNA complex showing that base-specific contacts are made within the sequence GGGTTA. To the best of our knowledge, RTBP1 is the first cloned gene in which the product is able to bind doublestranded telomeric DNA in plants. Because the Myb-like domain appears to be a significant motif for a large class of proteins that bind the duplex telomeric DNA, RTBP1 may play important roles in plant telomere function in vivo.

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We propose a novel design of photonic crystal fiber (PCF) using an elliptical air hole in the core as a defected core in order to enhance the performance of modal birefringence and to control the properties of chromatic dispersion at the same time. From the simulation results, it is shown that the proposed fiber has high birefringence up to the order of 10(-2), negative flattened chromatic dispersion in a broad range of wavelengths, and low confinement loss less than that of the single mode fiber. The outstanding advantage of the proposed PCF is that high birefringence, negative flattened dispersion, and low confinement loss can be achieved just by adding a small sized elliptical air hole in the core to the elliptical air hole PCF, especially at the same time.

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The single living cell action potential was measured in an intracellular mode by using a vertical nanoelectrode. For intracellular interfacing, Si nanowires were vertically grown in a controlled manner, and optimum conditions, such as diameter, length, and nanowire density, were determined by culturing cells on the nanowires. Vertical nanowire probes were then fabricated with a complimentary metal-oxide-semiconductor (CMOS) process including sequential deposition of the passivation and electrode layers on the nanowires, and a subsequent partial etching process. The fabricated nanowire probes had an approximately 60-nm diameter and were intracellular. These probes interfaced with a GH3 cell and measured the spontaneous action potential. It successfully measured the action potential, which rapidly reached a steady state with average peak amplitude of approximately 10 mV, duration of approximately 140 ms, and period of 0.9 Hz.

The hierarchical three‐dimensional nitrogen‐doped carbon nanotube anchored bimetallic cobalt copper organic framework (NCNT MOF CoCu) is successfully synthesized by the direct growth approach using the high‐temperature carbonization of bimetallic cobalt copper organic framework (MOF CoCu‐500). The as‐prepared NCNT MOF CoCu nanostructure possesses high‐level activity for both glucose and hydrogen peroxide (H2O2) sensing molecules. The cyclic voltammetry (CV) and chronoamperometry (CA) studies demonstrate excellent electrocatalytic performance for the oxidation of glucose with a linear range of 0.05 to 2.5 mM, high sensitivity of 1027 μA mM−1cm−2, and the lowest detection limit of 0.15 μM. Similarly, the NCNT MOF CoCu nanostructure showed significantly higher H2O2 activity with a linear range of 0.05 to 3.5 mM, high sensitivity of 639.5 μA mM−1cm−2, and the lowest detection limit of 0.206 μM. Thanks to its special hierarchical nanoarchitecture, homogeneous nitrogen‐doped carbon nanotubes, and highly graphitized carbon, which may be increased the synergistic effect between bimetallic CoCu and NCNT in the organic framework. The potentially effective fabricated sensor was also used as a suitable probe for the detection of glucose and H2O2 in the analysis of the real samples.

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