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A protocol has been developed to use human induced pluripotent stem cells to obtain a self-formed ectodermal autonomous multizone, which includes distinct cell lineages of the eye, including the ocular surface ectoderm, lens, neuro-retina, and retinal pigment epithelium that can be expanded to form a functional corneal epithelium when transplanted to an animal model of corneal visual impairment.

The two sets of paired appendages, called limbs, are locomotory organs in tetrapods that are used for various functions (e.g., walking, running, crawling, digging, climbing, diving, swimming, and flying). Unlike such organs as the eye, which contain specialized tissues such as the lens and photoreceptor, the limb does not have any specialized cells or tissues, but consists of common tissues, such as bone, cartilage, muscle, blood vessels, and dermis. However, limb morphology is highly specialized and varies to provide species-specific modes of locomotion. As do the vertebrae and skull, the limb skeleton varies in morphology among species. The diversity of limb skeletal morphology provides examples of material for studies on morphogenesis. Avian fore limbs have evolved into wings for flight. The skeletal pattern in the avian limb has many traits that are unique among extant species of vertebrates; some of such traits are avian-specific, others are shared with more basal members of Theropoda, to which Aves belongs. Since such avian traits generally form during ontogenic development, determining when and how they appear in the developing embryonic limbs or limb buds provides important insights into the mechanisms underlying the generation of vertebrate morphological diversity. Here, we present an overview of several features of the skeletal pattern in the avian limb and discuss the developmental mechanisms responsible for their unique and lineage-specific traits. [ABSTRACT FROM AUTHOR]

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The electrical properties of a beryllium-doped cubic boron nitride (c-BN) single crystal grown on (111) diamond were investigated by using electron-beam-induced current measurements as well as current–voltage (I–V) and capacitance–voltage measurements. The I–Vmeasurements through silver electrodes on c-BN showed non-linear characteristics, revealing Schottky behavior. From the temperature dependence of resistivity, the activation energy of 0.24eV was obtained. We observed electron-beam-induced currents under the silver electrode, which means that a depletion region was formed due to the Schottky barrier. The diffusion length of minority carriers was determined by scanning the electron beam across the Schottky contact. The transient current after the electron-beam pulse was also measured at various temperatures.

Scandium perfluoroalkanesulfonates and perfluoroalkanesulfonimides act as catalysts for the polyesterification of dicarboxylic acids by diols. We performed the model esterification between ethanol and acetic acid to measure the extent of the conversions and equilibrium constants for each scandium catalyst. According to the Arrhenius and Eyring constants, the activity of each scandium catalyst depends on its fluorine content and type of ligand, as reflected in the activation entropy values.

Pb(Zr, Ti)O3(PZT)/MgO/Si(001) stacked structures, one of the potential components of ferroelectric-gate field effect trnsistors, have been fabricated and characterized. According to the electrical characterization of MgO/Si structures, MgO thin films prepared on Si substrates at a low growth rate showed a small leakage current of ?10-8A/cm2order in an electric field of 1 MV/cm. In C-Vmeasurements of as-grown MgO/Si interfaces, injection-type hysteresis was observed because of crystal defects in the MgO film adjacent to the interface. After oxygen annealing at 400°C, however, it showed no hysteresis and a low interface trap density of the order of 1011cm-2eV-1was achieved with no formation of a low-dielectric layer at the MgO/Si interface. These results indicate that MgO thin films are applicable as gate insulators of FETs. After a PZT film was deposited on the MgO/Si structure, the C-Vcharacteristic of the stacked structure showed a ferroelectric hysteresis curve and a low interface trap density of 5×1011cm-2eV-1. A maximum memory window width of 1.2 V was obtained for the PZT thin film on Si substrate with a MgO intermediate layer.