Mutants of the nematode Caenorhabditis elegans that are defective specifically in their attraction to cycloheximide

The nematode Caenorhabditis elegans exhibits chemotaxis toward a wide variety of chemicals including water-soluble molecules and volatile organic compounds. We have previously discovered that C. elegans wild-type strain N2 is strongly attracted by cycloheximide which has long been known as a bitter tastant for humans and other mammals. We describe here the isolation and initial characterization of the first mutants which were defective specifically in their attraction to cycloheximide. In our screenings, we selected two mutants that were defective in chemotaxis to cycloheximide but normal in their attraction to NH4Cl and histidine. These mutants also avoided quinine hydrochloride, CuSO4 and high concentrations of NaCl similar to the wild-type strain N2. Furthermore, no observable defect was detected in their attraction to volatile odorants such as isoamyl alcohol and diacetyl. Dye-filling experiments suggested that they have no morphological defect in the sensory endings of the amphid neurons.     

Observation of New Longitudinal and Transverse Josephson Plasma Modes in the Parallel Magnetic Fields: Underdoped YBCO

Josephson plasma reflectivity edge in YBa₂Cu₃O_6.6 (T _c=59 K) was measured in parallel magnetic fields HCuO₂ up to 7 T. Upon application of the field, the Josephson plasma edge splits to two reflectivity edges, forming a new peak at finite frequency. Optical conductivity obtained by Kramers–Kronig analysis indicates that a new transverse Josephson plasma mode appears under parallel fields. We propose that the new mode originates from the modulation of the insulating layers with and without Josephson vortices, as has been suggested by free-energy calculations of Josephson vortices with moderate densities.     

Anodic acyloxylation based on the acid–base reactions between acetic acid or trifluoroacetic acid and solid-supported bases

We have developed a novel electrolytic system for anodic acyloxylation based on the acid–base reactions between acetic acid or trifluoroacetic acid and solid-supported bases. On the basis of the electrolytic system, anodic acyloxylation of organic compounds, which even have considerably high oxidation potentials, was successfully carried out to provide the corresponding acyloxylated products in moderate to excellent yields. Furthermore, it was found that silica gel supported bases are not only chemically stable under acidic conditions but also electrochemically stable and thus reusable for many times.     

Control scheme for optimizing the interferometer phase bias in a symmetric-Mach-Zehnder-type all-optical switch

A control scheme for accurately optimizing (and also automatically stabilizing) the interferometer phase bias of symmetric-Mach-Zehnder (SMZ)-type ultrafast all-optical switches is proposed. In this control scheme, weak continuous-wave light is used as supervisory input light and its spectral power ratio at the switch output is used as a bipolar error signal. Our experimental results for 168-Gb/s 16:1 demultiplexing with a hybrid-integrated SMZ switch indicate the feasibility and the sensitivity of this control scheme.     

Improving the photovoltaic performance of co‐evaporated Cu2ZnSnS4 thin‐film solar cells by incorporation of sodium from NaF layers

We have investigated the influence of sodium (Na) on the properties of co‐evaporated Cu₂ZnSnS₄ (CZTS) layer microstructures and solar cells. The photovoltaic performance and diode properties were improved by incorporating Na from NaF layers into the CZTS layers, while Na had a negligible effect on the microstructural properties of the layer. The best cell fabricated by using an optimal CZTS layer (Cu/(Zn + Sn) = 0.70, Zn/Sn = 1.8) yielded an active area efficiency of 5.23%. The analysis of device properties suggests that charge‐carrier recombination at CZTS/CdS interface is suppressed by intentional Na incorporation from NaF layers. Copyright © 2016 John Wiley & Sons, Ltd.     

Creep rupture properties of homopolymer,copolymer, and terpolymer based on poly(oxymethylene)

Polyacetal copolymers were prepared by cationic ring‐opening copolymerizations of 1,3,5‐trioxane (TOX) with 1,3‐dioxolane (DOX), and polyacetal terpolymers were prepared by terpolymerizations of TOX, DOX, and 2‐ethylhexyl glycidyl ether (EHGE). Polyacetal polymers with three different structures such as polyacetal homopolymers, polyacetal copolymers, and polyacetal terpolymers were compared in the mechanical properties and the creep characteristics, and discussed from the view point of the polymer structure. The polyacetal copolymers and the polyacetal terpolymers were determined by ¹H‐MNR measurement. About 80 mol % of DOX and EHGE amounts in feed were incorporated randomly into the each polymer. From the plots of the degree of crystallinity (X_c) versus the tensile strength, the tensile strength and crystallintiy of the polyacetal homopoymers are higher than those of the polyacetal copolymers and the polyacetal terpolymers. However, the tensile strength does not decrease linearly with a decrease in the crystallinity among the polyacetal polymers with three different structures, the polyacetal homopolymer, the polyacetal copolymers, and the polyacetal terpolymers. Creep rupture was characterized by the activation volume, υ_c, value in Zhurkov's equation, which can be estimated from the slope in the plots of load versus log (rupture time) at 80°C. The polyacetal polymers with higher molecular weight have larger values of the activation volume than those with lower molecular weight. When the activation volume values are compared among the polyacetal polymers with the same molecular weights, they increase in the following order: the polyacetal homopolymers < the polyacetal copolymers < polyacetal terpolymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

A hybrid approach to keyframe extraction from motion capture data using curve simplification and principal component analysis

In this paper, we propose a novel method to extract keyframes from motion capture data. A hybrid approach, which combines a curve‐simplification algorithm with an initialization procedure including principal component analysis, is adopted. The developed method automatically extracts an appropriate number of keyframes at high speed without performance degradation. Experimental results prove the effectiveness of the present method. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.