Immune Response to “Self” Lens in Xenopus laevis Enucleated during Larval Life

We have reinvestigated an important issue in the amphibian immunology that has not been settled for years since the pioneer work of Triplett, concerning the necessity of being exposed to organ-specific antigens early in development. It was found that syngeneic lenses were rejected by frogs, Xenopus laevis, that had been enucleated (eye removed) during early larval life. This rejection did not occur in intact frogs or in those enucleated in later larval or adult life. Whereas the splenocytes from intact frogs did not proliferate in response to a co-cultured syngeneic lens, those from frogs that had been enucleated at any of the larval stages, or even after metamorphosis, proliferated intensely. Both of these responses were shown to be thymus- dependent. In conclusion, it was demonstrated that the frog immune system rejected even syngeheic lenses by enucleation in early larval life and that it began to recognize the syngeneic lenses by lymphoid proliferation after enucleation, even in later life

2016年8月後半におけるアジアジェットの蛇行及びロスビー波の砕波に伴うモンスーントラフ強化の予測可能性

This study examines the predictability of an enhanced monsoon trough, which is accompanied by a largescale cyclone in the lower troposphere, south of Japan seen in late August 2016. The monsoon trough is found to be enhanced by a meandering of the Asian jet and a consequent southwestward intrusion of upper-level high potential vorticity associated with a Rossby wave breaking east of Japan. Japan Meteorological Agency's operational one-month ensemble prediction during the forecast period of a week underestimates the intensity of the Rossby wave breaking and fails to predict the enhanced monsoon trough. A simple sensitivity analysis based on ensemble singular vectors indicates that initial perturbations over the Bering Sea and near the Asian jet entrance region can efficiently grow and propagate toward the region to the south of Japan, contributing to maximize the perturbations of the enhanced monsoon trough. The time evolution of the perturbations propagating toward the region to the south of Japan is consistent with that of the ensemble spread during the forecast period. Perturbed hindcast experiments were conducted with the initial perturbations obtained from the simple sensitivity analysis. The monsoon trough to the south of Japan in the perturbed experiment is significantly more enhanced than the unperturbed experiment, supporting the simple sensitivity analysis. These results indicate a crucial contribution of the initial perturbations associated with the Rossby wave breaking and near the Asian jet entrance region to the limited predictability of the enhanced monsoon trough in late August 2016.2016年8月下旬に日本の南海上の対流圏下層で発達した、大規模な低気圧を伴うモンスーントラフの予測可能性を調べた。このモンスーントラフはアジアジェットの蛇行、及びそれに伴う日本の東海上でのロスビー波の砕波と関連する上層での高渦位大気の南西方向への侵入によって強化されたことが分かった。気象庁現業1か月アンサンブル予報は、予測初期1週間においてロスビー波の砕波の強度を過小に予測し、モンスーントラフの強化を予測できなかった。アンサンブル特異ベクトル法に基づく簡易予報感度解析の結果、ベーリング海やアジアジェット入口付近にあった初期摂動は、効率的に成長しながら日本の南海上に向かって伝播し、モンスーントラフを強化する摂動の最大化に寄与しうることが分かった。日本の南海上に向かって伝播する摂動の時間発展は、予測期間におけるアンサンブルスプレッドの時間発展と対応していた。簡易予報感度解析より得られた初期摂動を与えた再予報実験を行った結果、摂動を与えた実験では、摂動を与えなかった実験と比べて日本の南海上でのモンスーントラフの強化がより明瞭となり、簡易予報感度解析の結果と整合していた。これらの結果は、ロスビー波の砕波及びアジアジェット入口付近における初期摂動が、2016年8月後半に強化したモンスーントラフの予測可能性に大きく寄与したことを示している

Ion−Ion Interactions and Conduction Mechanism of Highly Conductive Fluorohydrogenate Ionic Liquids

Ion−ion interactions in highly conductive fluorohydrogenate ionic liquids (ILs) are discussed in this study. Low-temperature crystal structures of DMIm(FH)₂F and DMIm(FH)₃F (DMIm = 1, 3-dimethylimidazolium) are determined by single-crystal X-ray diffraction to obtain the location of each ion in the crystal lattice. Interaction energies between the imidazolium cation and fluorohydrogenate anions are evaluated with the aid of quantum mechanical calculations where the configuration of the ions is taken from the crystal structures of DMIm(FH)₂F and DMIm(FH)₃F as well as the previously determined EMImFHF (EMIm = 1-ethyl-3-methylimidazolium). The calculation suggests that the interaction energies are mainly dominated by electrostatic interactions as in the cases of other imidazolium salts, and the low viscosity and high conductivity of fluorohydrogenate ILs are derived from their dynamic properties. The HF unit exchanging between fluorohydrogenate anions weakens the cation−anion interactions and produces smaller anionic diffusion species

EFSO at different geographical locations verified with observing-system experiments

ひとつひとつの観測データが気象予測に与える影響を簡易に評価する手法を確認 --北極の観測データは7日先の北米気象予測の改善に貢献することも明らかに--. 京都大学プレスリリース. 2021-04-30.An ensemble-based forecast sensitivity to observations (EFSO) diagnosis has been implemented in an atmospheric general circulation model–ensemble Kalman filter data assimilation system to estimate the impacts of specific observations from the quasi-operational global observing system on weekly short-range forecasts. It was examined whether EFSO reasonably approximates the impacts of a subset of observations from specific geographical locations for 6-hour forecasts, and how long the 6-hour observation impacts can be retained during the 7-day forecast period. The reference for these forecasts was obtained from 12 data denial experiments in each of which a subset of three radiosonde observations launched from a geographical location was excluded. The 12 locations were selected from three latitudinal bands comprising (i) four Arctic regions, (ii) four midlatitude regions in the Northern Hemisphere, and (iii) four tropical regions during the Northern Hemisphere winter of 2015/16. The estimated winter-averaged EFSO-derived observation impacts well corresponded to the 6-hour observation impacts obtained by the data denials and EFSO could reasonably estimate the observation impacts by the data denials on short-range (6-hour to 2-day) forecasts. Furthermore, during the medium-range (4-day to 7-day) forecasts, it was found that the Arctic observations tend to seed the broadest impacts and their short-range observation impacts could be projected to beneficial impacts in Arctic and midlatitude North American areas. The midlatitude area located just downstream of dynamical propagation from the Arctic toward the midlatitudes. Results obtained by repeated Arctic data-denial experiments were found to be generally common to those from the non-repeated experiments

Programmable time-multiplexed squeezed light source

One of the leading approaches to large-scale quantum information processing (QIP) is the continuous-variable (CV) scheme based on time multiplexing (TM). As a fundamental building block for this approach, quantum light sources to sequentially produce time-multiplexed squeezed-light pulses are required; however, conventional CV TM experiments have used fixed light sources that can only output the squeezed pulses with the same squeezing levels and phases. We here demonstrate a programmable time-multiplexed squeezed light source that can generate sequential squeezed pulses with various squeezing levels and phases at a time interval below 100 ns. The generation pattern can be arbitrarily chosen by software without changing its hardware configuration. This is enabled by using a waveguide optical parametric amplifier and modulating its continuous pump light. Our light source will implement various large-scale CV QIP tasks.Comment: 14 pages, 7 figure

Fabrication of large preforms for low-loss single-mode optical fibers by a hybridized process

Α hybridized fabrication process for single-mode optical fibers has been studied. The process consists of direct overcladding a VAD derived core rod with a porous body made from commercial silica powder by means of the cold isostatic pressing technique. By using a mixture of main silica powder with an average particle diameter of 10 µm and 1 w t% of fine silica powder with an average particle diameter of 0.04 µm and a core rod having a core/cladding diameter ratio of 1/2.4 as starting materials, large preforms for 300 km fibers were fabricated, which were drawn into fibers with attenuation losses of 0.350 dB/km at 1.31 µm and 0.232 dB/km at 1.55 µm. In the process, a special rubber mold with a structure in which both ends of the core rod are pressed by hydrostatic pressure makes the fabrication of large hybridized soot preforms possible, plastic deformation of the porous body during degreasing being remarkably reduced by using a suitable content of glycerol

Optical switching of nematic liquid crystal by means of photoresponsive polyimides as an alignment layer

Photosensitive polyimides (PIs) as an alignment layer induced optical switching of nematic liquid crystal (NLC) on photoirradiation at 366 nm. The orientation of NLC molecule was changed from homogeneous to homeotropic alignment on photoirradiation with a dc electric field as a bias. The optical switching behavior of NLC was largely affected by the chemical structures of PIs. (C) 1999 American Institute of Physics. [S0003-6951(99)02748-5]open91