Cell culture on polymers prepared by radiation-induced polymerization of various glass-forming monomers

The growth of cells on polymers prepared by the radiation polymerization of monomethacrylate and dimethacrylate was investigated. Cell growth was affected greatly by such properties of the polymers as water content, wettability, and porosity. Growth was promoted remarkably by rinsing the polymers with warm water at 60-70 degrees C and by irradiation of polymers with an electron beam. Cell growth decreased with increasing oxyethylene length (n) in the polymerized dimethacrylate of same series, CH2C(CH3)CO(OCH2CH2)nOCOC(CH3)CH2. A decrease in the hydrophilicity of the polymer increased cell growth rate. Formation of pore structures in the polymer films also increased the cell growth.     

Real-time measurements of protein dynamics using fluorescence activation-coupled protein labeling method

We present a fluorescence activation-coupled protein labeling (FAPL) method, which employs small-molecular probes that exhibit almost no basal fluorescence but acquire strong fluorescence upon covalent binding to tag-proteins. This method enables real-time imaging of protein labeling without any washout process and is uniquely suitable for real-time imaging of protein dynamics on the cell surface. We applied this method to address the spatiotemporal dynamics of the EGF receptor during cell migration.     

Depth-control method for integral imaging

We present a method for controlling the depth of three-dimensional (3D) images reconstructed by integral photography. Incoherent light is reflected from 3D objects, propagates through a lens array, and is captured as the first elemental images by a capturing device. The second elemental images of the 3D images are generated by numerical processing from the first elemental images in accordance with the desired depth. The optical reconstruction of 3D images at the desired depth by the second elemental images is confirmed experimentally.     

Geometric analysis of spatial distortion in projection-type integral imaging

In projection-type integral imaging, positional errors in elemental images and elemental lenses affect three-dimensional (3D) image quality. We analyzed the relationships between the geometric distortion in elemental images caused by a projection lens and the spatial distortion in the reconstructed 3D image. As a result, we clarified that 3D images that were reconstructed far from the lens array were largely affected, and that the reconstructed images were significantly distorted in the depth direction at the corners of the displayed images.     

Error Correcting Sequence and Projective De Bruijn Graph

Let X be a finite set of q elements, and n, K, d be integers. A subset C ⊂ X ⁿ is an (n, K, d) error-correcting code, if #(C) = K and its minimum distance is d. We define an (n, K, d) error-correcting sequence over X as a periodic sequence {a _i } _i=0,1,... (a _i ∈ X) with period K, such that the set of all consecutive n-tuples of this sequence form an (n, K, d) error-correcting code over X. Under a moderate conjecture on the existence of some type of primitive polynomials, we prove that there is a error correcting sequence, such that its code-set is the q-ary Hamming code with 0 removed, for q > 2 being a prime power. For the case q = 2, under a similar conjecture, we prove that there is a error-correcting sequence, such that its code-set supplemented with 0 is the subset of the binary Hamming code [2 ^m  − 1, 2 ^m  − 1 − m, 3] obtained by requiring one specified coordinate being 0. Received: October 27, 2005. Final Version received: December 31, 2007