A high performance distillation system to remove krypton from xenon was constructed, and a purity level of Kr/Xe = ∼ 3 × 10 −12 was achieved. This development is crucial in facilitating high sensitivity low background experiments such as the search for dark matter in the universe.

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A method for extracting coherent vorticity sheets and current sheets out of three-dimensional homogeneous magnetohydrodynamic ͑MHD͒ turbulence is proposed, which is based on the orthogonal wavelet decomposition of the vorticity and current density fields. Thresholding the wavelet coefficients allows both fields to be split into coherent and incoherent parts. The fields to be analyzed are obtained by direct numerical simulation ͑DNS͒ of forced incompressible MHD turbulence without mean magnetic field, using a classical Fourier spectral method at a resolution of 512 3. Coherent vorticity sheets and current sheets are extracted from the DNS data at a given time instant. It is found that the coherent vorticity and current density preserve both the vorticity sheets and the current sheets present in the total fields while retaining only a few percent of the degrees of freedom. The incoherent vorticity and current density are shown to be structureless and of mainly dissipative nature. The spectral distributions of kinetic and magnetic energies of the coherent fields only differ in the dissipative range, while the corresponding incoherent fields exhibit near-equipartition of energy. The probability distribution functions of total and coherent fields for both vorticity and current density coincide almost perfectly, while the incoherent fields have strongly reduced variances. Studying the energy flux confirms that the nonlinear dynamics is fully captured by the coherent fields only.

Cap analogues having differently methylated adenosine at 2' and N6 position, m(7)G(5')pppApG which is existed in plant mRNA (plant type), m(7)G(5')pppAmpG (animal type), m(7)G(5')pppm(6)AmpG (mammalian type) and m(7)G(5')pppm(6)ApG (unnnatural type), were synthesized. In order to clarify the function of these methyl groups, luciferase mRNAs having differently methylated adenosine at the 5'-terminus, were successfully prepared by in vitro transcription using the synthesized cap anologues. As the preliminary results of in vitro translation with rabbit reticulocyte lysate and luciferase assay, luciferase mRNA having the mammalian type of cap structure, m(7)G(5')pppm(6)AmpG, was most efficiently translated. In the case of m(7)G(5')pppApG (plant type) efficiency of translation was lowest.

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