Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

Inhibitory and promotive allelopathy in rice (Oryza sativa L.)

Abstract: Studies on allelopathic rice, which inhibits the germination and development of weeds such as barnyardgrass (Echinochloa spp.) and ducksalad [Heteranthera limosa (Sw.) Wild.], have been strongly conducted in the USA, the Philippines, Japan, Korea, and other countries since the 1980s. Weed-suppressing rice plants can compete with weeds for light and mineral nutrients by their rapid and thick growth characteristics, and probably also by their allelopathic effects. It was suggested that allelopathic properties were inherited from parents. Different screening methods for finding allelopathic rice simply and rapidly have been proposed. In contrast, stimulative allelopathy in rice, which promotes germination of the dormant and dormancy-awakened seeds of Monochoria vaginalis (Burm. f.) Kunth var. vaginalis, has been investigated by the authors since the 1990s. Rice seeds promoted the germination in the dark and in light under submerged conditions. Our experiments suggested that rice seeds, hulls, plants and straw contain stimulative substance(s) that promote seed germination of M. vaginalis.

Higher-Order Structure Formation in Adsorbed Monolayers at Aqueous Solution Surfaces Studied by Brewster Angle Microscopy

Abstract: The first-order phase transitions in adsorbed monolayers of 2-hydroxyethyl laurate have been studied by film balance and Brewster angle microscopy (BAM). A cusp point in the surface pressure−time (π−t) curves indicates the commencemnet of phase transition. The critical surface pressure necessary for the phase transition increases with increasing temperature. Large size circular domains having characterishtic internal stripes are observed up to 10 °C. The width of the stripes increases with increasing termperature. The separate stripes in a domain undergo continuous narrowing into a core defect which lies on the domain peripheral line at 2 °C. The core defect seems to be also present at higher temperatures but remains far out of the doman boundary at 10 °C. Two surface phases observed after the cusp points by BAM are pseudo equilibrium state and the global equilibrium is attained with the formation of one condensed surface phase after a long time.

Henle Fiber Layer Phase Retardation Measured With Polarization-Sensitive Optical Coherence Tomography

Abstract: We developed a method based on polarization-sensitive optical coherence tomography (PS-OCT) to quantify the double pass phase retardation (DPPR) induced by Henle fiber layer in three subjects. Measurements of the retina were performed at a mean wavelength of 840 nm using two polarization states that were perpendicular in a Poincare sphere representation and phase retardation contributions from tissue layers above and below the Henle fiber layer were excluded using appropriately placed reference and measurement points. These points were semi-automatically segmented from intensity data. Using a new algorithm to determine DPPR, the Henle fiber layer in three healthy subjects aged 50-60 years showed elevated DPPR in a concentric ring about the fovea, with an average maximum DPPR for the three subjects of 22.0° (range: 20.4° to 23.0°) occurring at an average retinal eccentricity of 1.8° (range: 1.5° to 2.25°). Outside the ring, a floor of approximately 6.8° was measured, which we show can mainly be attributed to phase noise that is induced in the polarization states. We also demonstrate the method can determine fast axis orientation of the retardation, which is found consistent with the known radial pattern of Henle fibers.

Response of Japanese beech (Fagus japonica Maxim.) sprouts to canopy gaps.

Abstract: The response of Japanese beech (Fagus japonica Maxim.) sprouts to canopy gaps in natural beech forest in central Japan was studied using two contrasted gaps in which tree-ring chronologies of regenerating stems were analyzed. The gaps were created by uprooting of a single Quercus mongolica var. grosseserrata stem (diameter: 50 cm; gap size: 40 m2; 23 years old) and by concurrent uprootings of four F. japonica stools (gap size: 180 m2; 30 years old). Japanese beech sprouts emerged before and after the gap formation and dominated stem populations in both gaps. In gaps, growth of F. japonica sprouts was equal or lower than growth of stems of seed origin, but most sprouts (F. japonica, Acer mono var. marmoratum) appeared a few years before emergence of seedlings. The small gap created by single stem fall was dominated by some beech sprouts from stools adjacent to the gap. The multiple gap was not closed by beech sprouts from stools surrounding the gap, but some dominant beech stems were resprouts from the uprooted beech stools. The existence of a ‘sprout bank’ under the canopy may play an important role in the closing process of gaps in natural Japanese beech forest.

Preparation of aminosilane–alginate hybrid microcapsules and their use for enzyme encapsulation

Abstract: Organic–inorganic hybrid microcapsules (AP-capsules) were fabricated by sequential preparation of calcium alginate microcapsules (Alg-capsules), followed by the addition of the Alg-capsules to an aqueous solution of 3-aminopropyltriethoxysilane (APTES) in mild conditions without the use of any catalyst. Results showed that the shell thickness of AP-capsules was found to vary with time during the APTES incorporation onto the Alg-capsules, suggesting that the shell thickness was dependent on the amount of CaCl2 contained initially in the core solution as well as on the reaction time. A model enzyme, formate dehydrogenase (FDH), was successfully encapsulated in AP-capsules, and maximum efficiency of encapsulation was found with the capsule size of 1 mm diameter. The AP-capsules were reused efficiently for 10 cycles without loss of FDH activity. The approach developed in this study could evolve as a generic platform of enzyme immobilization for biotechnology applications using core–shell microcapsule technology.