No abstract available

[en] AIM2 is an innate immune sensor of microbial double-stranded DNA. The HIN-200 domain of mouse AIM2 bound to a 15 bp and an 18 bp dsDNA were crystallized and diffract to about 4.0 Å. AIM2 (absent in melanoma 2) is an innate immune receptor for cytosolic double-stranded DNA (dsDNA). The engagement of dsDNA by AIM2 activates the AIM2 inflammasome, resulting in the cleavage of pro-interleukin-1β by caspase-1. The DNA-binding HIN-200 domain of mouse AIM2 bound to a 15 bp dsDNA and to an 18 bp dsDNA was purified and crystallized. The AIM2 HIN-200 domain in complex with the 15 bp DNA crystallized in the cubic space group I23 or I2₁3, with unit-cell parameter a = 235.60 Å. The complex of the AIM2 HIN-200 domain and the 18 bp DNA crystallized in a similar unit cell. Diffraction data for the two complexes were collected to about 4.0 Å resolution. Mutagenesis and DNA-binding studies suggest that mouse AIM2 uses a similar surface to human AIM2 to recognize DNA

[en] The cesium fountain primary frequency standard NIM5 has been developed at the National Institute of Metrology in China. The NIM5 loads atoms in an optical molasses from the background Cs vapor directly. Atoms are then cooled to a temperature of about 2 μK and launched to a height of 81 cm. The fringes of the Ramsey pattern have a width of 0.98 Hz. The NIM5 operates for more than 300 d a year, operating nearly continuously for 15 d at a time. By stabilizing the 9.19 GHz microwave frequency to the center of the central Ramsey fringe, a typical fractional frequency instability of 3*10^-13 (τ/s)^-1/2 is obtained when running at high atom density, and a combined uncertainty, including Type A and B uncertainties, is typically 1.6*10^-15. Comparisons of data between NIM5 and 5 other fountain clocks were carried out in May 2013 via two-way satellite time and frequency transfer (TWSTFT), and the results show good agreement within the uncertainties. Six groups of NIM5 data from January to June 2014 have been published in Circular T 319 and 320. (authors)

[en] There was a west-east gas transmission pipeline nearby the Yanmenguan DC grounding electrode. In order to assess the electromagnetic interference of Yanmenguan DC grounding electrode on the pipeline, an electromagnetic simulation model was established. The pipeline to earth potential was analyzed. The effects of insulation layers and insulation joints on the pipeline to earth potential were investigated. It can provide theorical support for the pratical operation of gas pipelines. (paper)

[en] A simple one-step pyrolysis strategy has been developed to prepare molybdenum dioxide supported on nitrogen-doped graphene (MoO₂/NG) as electrocatalyst for oxygen reduction reactions (ORR). Homogeneous anchoring of MoO₂ nanoparticles on nitrogen-doped graphene was achieved for the composite synthesized at 500 °C (MoO₂/NG-500). For the first time, the MoO₂/NG composite manifests considerable electrocatalytic activity for ORR in alkaline solution, with the onset potential of 0.91 V and the peak potential of 0.73 V. Furthermore, the MoO₂/NG catalyst outperforms commercial Pt/C catalyst in terms of the electrochemical durability for ORR. The facile fabrication, reasonable ORR activity and excellent stability endow our MoO₂/NG catalyst with great promise in application of cost-effective fuel cells.