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31.
We describe herein the synthesis and properties of the novel nucleoside derivative, 4,7-diamino-2-(2-deoxy-β-d-erythro-pentofuranosyl)-2,6-dihydro-7H-2,3,5,6-tetraazabenzo[cd]azulene (1). The palladium catalyzed cross-coupling reaction of 2,4-diamino-5-iodo-7-(2-deoxy-β-d-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine (9) with acrylonitrile afforded 2,4-diamino-5-[(E)-1-cyano-2-ethenyl]-7-(2-deoxy-β-d-erythro-pentofuranosyl)pyrrolo[2,3-d]pyrimidine (10) in 77% yield, which was treated with NaOMe in MeOH in the presence of NaSPh to give the desired 1 in 64% yield. Whereas 1 was stable in concentrated ammonia at room temperature, it was gradually hydrolyzed in water to give 4-amino-2-(2-deoxy-β-d-erythro-pentofuranosyl)-2,6-dihydro-7H-2,3,5,6-tetraazabenzo[cd]azulen-7-one (12). Density functional calculations indicated that 12 was 20 kcal/mol more thermodynamically stable than 1 in a model study.  相似文献   
32.
33.
Ion exchange fabric (IEF) having the functional group of sulfonic acid was synthesized by radiation grafting of glycidyl methacrylate on a polyethylene nonwoven fabric and subsequent chemical modification. Total organic carbon eluted from the resulting IEF could be reduced to the concentration less than 1 ppb after washing with organic solvents. Adsorption performance of the obtained IEF was evaluated by 10 ppb Na+ solution. The column packed IEF, 7 mm in diameter and 20 mm high, could remove the Na+ at the distribution coefficient of 1.2×107 at linear velocity of 400 m/h. At column height of 95 mm, the breakthrough point reached 2.0×105 in bed volume and the degree of column utilization was improved up to 18.7%. From these results, the IEF synthesized by graft polymerization was considered to be applicable for water purification in ultra-pure water production.  相似文献   
34.
A bispectral method for astronomical speckle imaging utilizes an average speckle bispectrum of an object to derive its Fourier phase. There has been, however, a problem in conventional bispectral algorithm owing to difficulty in processing bispectral data in a four-dimensional (4D) space. In this paper, we propose an implementation to overcome this problem, where a one-dimensional (1D) object projection is reconstructed from a two-dimensional (2D) average bispectrum of speckle projections, and object projections so obtained at various angles are then tomographically combined into a 2D object image. In this tomographic approach, processes are separable into those for individual projection angles, implying that bispectral data required to be stored at a time are from 4D to 2D and computation time can be substantially reduced by parallelizing angle-by-angle processes. We have performed experiments using simulated and observed data, and have demonstrated the feasibility of the present approach with an achievable accuracy comparable to that of a conventional approach.  相似文献   
35.
In this paper, a new image enlargement method applying the backprojection for lost pixel (BPLP) to the predefined codebook-based method is proposed. BPLP is a method for image restoration. In BPLP, the eigenspace reflecting the characteristics of an input image is generated from the remained pixels and is used to restore the missing pixels. In the proposed method, the eigenspace is replaced by one generated from the predefined codebook (PDC). PDC represents edge-blurring properties in a small image patch and consists of pairs of low- and high-frequency image patches on various edge patterns. By replacing the PDC-based estimation of lost high-frequency components with BPLP, a fast image enlargement method retaining its performance can be developed. Through some experiments, the effectiveness of the proposed method was demonstrated. Especially, it was confirmed that the processing time of the proposed method was shortened to about 1/50 that of the PDC-based method.  相似文献   
36.
We consider positive solutions of elliptic partial differential equations on non-compact domains of Riemannian manifolds. We explicitly determine Martin compactifications and Martin kernels for a wide class of elliptic equations in skew product form by exploiting parabolic Martin kernels for associated parabolic equations.  相似文献   
37.
Mesoscopic nanomaterials with a size ranging from a few nanometers to hundreds of nanometers were generated on a metallic thin film by interfering femtosecond (fs) laser processing. Because the nanomaterials seemed to demonstrate liquid behavior, we named their structure nano water drop. The structure is considerably similar to that of a real water drop observed with a high-speed camera. Using the phase shift between interfering beams, a duplicate structure was generated. This is a new surface modification technique, using a top-down approach.  相似文献   
38.
The synthesis of the 3'-deoxyapionucleoside 3'-triphosphates (apioNTPs) having the four natural nucleobases and their enzymatic incorporation into a DNA-DNA primer-template have been tried. Therminator DNA polymerase was shown to incorporate these apioNTPs effectively giving 43mer DNA-apioNA chimera.  相似文献   
39.
The solid‐state chiral optical properties of a 4‐(2‐arylethynyl)‐benzoic acid/amine supramolecular organic fluorophore can be controlled by changing the arylethynyl group of the achiral 4‐(2‐arylethynyl)‐benzoic acid component molecule rather than the chirality of the amine component molecule.  相似文献   
40.
Objective: To investigate changes in hip and knee muscle strength in patients before and after total hip arthroplasty (THA) in comparison with that in healthy adults. Methods: The study included 21 women who underwent unilateral THA (THA group) and 21 age-matched healthy women (healthy group). Maximal isometric strengths of hip flexors, extensors, and abductors, and knee extensors and flexors were measured before surgery and at 4 weeks and 6 months after surgery. Results: Before surgery, muscle strength on both sides, except for hip flexors on the uninvolved side, was significantly lower in the THA group than the corresponding muscle strength in the healthy group. Up to 6 months after THA, strength of all muscle groups on both sides was significantly improved compared with their preoperative status, although the knee extensor strength on the involved side temporarily worsened at 4 weeks. However, the strength of hip extensors and knee extensors on the involved side, and hip abductors on both sides in the THA group remained below that in the healthy group. Conclusions: Our results suggest that rehabilitation specialists should consider increasing the focus on the uninvolved side and encourage patients to continue strength training beyond 6 months after surgery.  相似文献   
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