Phase unwrapping method along radial coordinates for speckle image reconstruction

We describe a phase estimating technique for a stellar speckle image reconstruction, which is based on the phase unwrapping method in polar coordinates. The phase unwrapping along radial lines is favorable to reduce accumulating errors in the phase estimation. This method is combined with Bruck-Sodin method which gives the estimate of the modulus of an object transform without a point reference source. Computer simulations of the image reconstruction are presented.     

Optical inverse radon transform

Mathematical formulation of an optical processesor that implements the inverse radon transform is described. This operation is of use in X-ray computed tomography, transaxial scanning and other image construction systems. The optical system outlined uses the convolution of two two-dimensional functions to achieve the inverse radon transform by a new implementation method.     

Versatile glycoblotting nanoparticles for high-throughput protein glycomics

We have developed an effective and practical trap-and-release method based on chemoselective ligation of carbohydrates with reactive aminooxyl groups attached to the surface of nanoparticles (referred to as glycoblotting nanoparticles). These glycoblotting nanoparticles were synthesized by UV irradiation of diacetylene-functionalized lipids that contain the aminooxyl group. The glycoblotting nanoparticles captured carbohydrates in aqueous solution under mild conditions and were collected by simple centrifugation. The trapped carbohydrates were effectively released from the nanoparticles under acidic conditions to give pure oligosaccharides. This glycoblotting process reduced the time required for the purification process of carbohydrates to less than 6 h, compared to the several days needed for conventional chromatographic techniques. The oligosaccharides (N-glycan) were released from ovalbumin (glycoprotein) by PNGase F after tryptic digestion. MALDI-TOF mass spectra before purification did not show any significant signals corresponding to N-glycans because these signals were hidden by the large signals of the abundant peptides. However, after purification with the glycoblotting nanoparticles, only signals corresponding to oligosaccharides appeared. We also demonstrated a clear analysis of the oligosaccharides contained in the mice dermis by means of glycoblotting.     

Versatile diastereoselectivity in formal [3,3]-sigmatropic shifts of substituted 1-alkenyl-3-alkylidenecyclobutanols and their silyl ethers

A new method for the preparation of highly substituted cyclohexenones is reported. [2 + 2] Cycloaddition of 2-silyloxydienes with allenecarboxylate affords the 1-alkenyl-3-alkylidenecyclobutanol silyl ethers. Thermolysis of these compounds affords the methylene cyclohexenyl silyl ethers with excellent exo selectivity (>95:5) when monosubstituted alkenyl groups are used, while the use of disubstituted alkenyl groups gives generally low selectivity ( approximately 2:1). However, rearrangement of the anion of the cyclobutanol (prepared by acidic hydrolysis of the TMS silyl ether) at low temperature gives the endo product with good to excellent diastereoselectivity (5-23:1). Two different mechanistic rationales are given for the two different processes: the first via a diradical and the second via a cleavage intramolecular Michael addition. Thus, the same starting material (e.g., 20) can be converted into either the exo or endo product, 22x or 22n, with good diastereocontrol by just changing the rearrangement conditions.     

The transitional process in the Cu3Au alloy from the disordered state to the ordered state

The ordering process in the Cu₃Au alloy from the disordered state is examined experimentally. The time evolution of the cluster size is observed by measuring the X-ray superstructure line width at several temperatures. It is found that the cluster size grows very slowly in the early stage, and then increases more rapidly in obedience to the $\text{t}{}^{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$ law which is apparently explained by the theory of Kawasaki et al.     

Beta-ray spectra of 12B and 12N and conserved vector current

In order to investigate spectral shape factors of ¹²B and ¹²N, we make a new formalism of β-decay theory, where the radial wave functions of leptons are treated with no approximation and, therefore, the nuclear matrix elements are electron-energy dependent. With this formalism we can show strong support for the conserved vector current hypothesis in analyzing the experimental data which were given by Wu, Lee and Mo in 1963 and revised by them in 1977 using the latest experimental results on the end-point energies and branching ratios of the inner β-groups, in addition to the correct Fermi functions for the positron. In fact, the average slopes of the spectral shape factors for ¹²B and ¹²N are in excellent agreement with those in our theory. Recent experimental data given by the Heidelberg group are also in good agreement with the theory if we analyze the difference of the average slopes for ¹²B and ¹²N. There are, however, small discrepancies with the theory in their individual values. The relation of the present formalism with traditional theories of β-decay is discussed.