アタラシイ ニホンゴ ノウリョク シケン ノ タメノ ゴイ ヒョウ サクセイ ニ ムケテ

日本語能力試験の実施機関である国際交流基金と日本国際教育支援協会は「日本語能力試験の改善に関する検討会」を2005年に発足させたが、2009年からの新試験開始を目指して各分科会は日々調査研究を重ねている。本稿は、分科会の一つである出題基準分科会漢字表・語彙表部会が行っている語彙表作成作業の2007年9月現在の中間報告である。 部会の活動は、この2年間で4つの段階を経た。作成方針と選別方針を決定し、データベースに関する調査および整備をする第一段階、語彙の選別をする第二段階、語彙の再選別及び記述方法の検討をする第三段階、語彙の再選別と初出級の検討をする第四段階である。実際にどのようなデータベースを使い、どのような検討を重ね、どのような選別作業をしたのか。本稿ではそれぞれの段階ごとに具体的な例を挙げながら報告をする。また、それとともに今後考えていかなければならない課題についても言及する。The Japan Foundation and Japan Educational Exchanges and Services inaugurated an "Examination Committee on Improving Japanese Language Proficiency Test" in 2005, and have been conducting research on the New Test to be incorporated in 2009. There are various revisions to be made. This is an interim report as of September 2007, on the working of vocabulary list which has been made by the kanji and vocabulary list subdivision of the Test Content Specifications division. The activities of the subdivision have been divided into four stages during these two years. The first stage is for decisions on the policy for composition and selection, and research on the database. The second stage is for the selection of vocabulary. The third stage is for discussion on the re-selection and description of vocabulary. The forth stage is for re-selection of vocabulary and for each level to be decided

Growth Dynamics of Domains in Ternary Fluid Vesicles

この論文は国立情報学研究所の電子図書館事業により電子化されました。研究会報告飽和リン脂質、不飽和リン脂質、コレステロールからなる3成分ベシクルにおける液体ドメインの成長ダイナミクスを蛍光顕微鏡観察した結果、Normal coarseningとTrapped coarseningに分けられた。Normal coarseningを示すベシクルは余剰面積をほぼ持たず、ドメインは2次元のスケーリング則t～D^2lnD(Dはドメインサイズ)に従ってBuddingせずに成長する。しかし成長の初期過程では流体力学的相互作用によるずれが生じる。一方、Trapped coarseningを示すベシクルは大きな余剰面積を持ち、ドメインはあるサイズまで成長するとBuddingしTrapされる。Buddingしたドメインが近づくと、ドメイン間に挟まれたマトリックスの曲げエネルギーが増大し、ドメインの合体を妨げる斥力を生む。Buddingしたドメインを持つベシクルの自由エネルギーの解析から、ベシクルの持つ余剰面積がある値よりも大きい時、余剰面積が大きい程コースニングのより初期課程でBuddingしTrapされることが分かり、実験結果を説明することが出来た

Numerical investigations of the dynamics of two-component vesicles.

We examined the dynamics of the deformation and phase separation of two-component vesicles. First, we numerically investigated the effects of (i) thermal noise, (ii) hydrodynamic flow induced by the line tension of the domain boundary and (iii) composition-dependent bending rigidity on the coarsening dynamics of a phase-separated pattern on the surfaces of vesicles with fixed shapes. The dynamical exponent z (N(DB) ∼ t(-z), the total length of the domain boundaries) of the coarsening of the phase-separated pattern was found to decrease from z = 1/3 under no thermal noise to 1/5 < z < 1/4 when including the effects of thermal noise. We also found that the hydrodynamic effect enhances the coarsening in a bicontinuous phase separation for a spherical vesicle. In phase separations of a shape-fixed tubular vesicle, a band-like phase separation with periodicity along the longer axis of the tube occurs because of the composition-dependent bending rigidity and the higher curvatures at the tube end-caps. Second, we also explored the dynamics of shape deformation coupled with phase separation through the bending rigidity of the membrane which depends on the local composition in lipids and found that the composition-dependent bending rigidity crucially influences the phase separation and deformation of the vesicle. The results of simulations are in good agreement with experimentally observed behavior known as 'shape convergence' (Yanagisawa et al 2008 Phys. Rev. Lett. 100 148102)

Emergence of a thread-like pattern with charged phospholipids on an oil∕water interface.

The spontaneous formation of a thread-like pattern with negatively charged lipids on an oil∕water interface is reported. An analysis of the time-dependent change at the interface observed by fluorescence microscopy revealed that the thread-like pattern is generated through a two-step mechanism. First, inverted lipid micelles in the bulk-oil phase gradually diffuse onto the oil∕water interface. Next, the micelles are adsorbed on the interface and self-assemble to form the thread-like pattern. The essential characteristics of this pattern formation are theoretically reproduced by a simple Monte Carlo simulation that takes into account the kinetics in the coalescence of charged micelles on a 2D interface

Evaporation Patterns of Dextran&ndash;Poly(Ethylene Glycol) Droplets with Changes in Wettability and Compatibility

The dextran&ndash;PEG system is one of the most famous systems exhibiting phase separation. Various phase behaviors, including the evaporation process of the dextran&ndash;PEG system, have been studied in order to understand the physicochemical mechanism of intracellular phase separation and the effect of condensation on the origin of life. However, there have been few studies in dilute regime. In this study, we focused on such regimes and analyzed the pattern formation by evaporation. The specificity of this regime is the slow onset of phase separation due to low initial concentration, and the separated phases can have contrasting wettability to the substrate as evaporation progresses. When the polymer concentration is rather low (&lt;5 wt%), the dextran&ndash;PEG droplets form a phase-separated pattern, consisting of PEG at the center and dextran ring of multiple strings pulling from the ring. This pattern formation is explained from the difference in wettability and compatibility between dextran and PEG upon condensation. At the initial dilute stage, the dextran-rich phase with higher wettability accumulates at the contact line of the droplet to form a ring pattern, and then forms multiple domains due to density fluctuation. The less wettable PEG phase recedes and pulls the dextran domains, causing them to deform into strings. Further condensation leads to phase separation, and the condensed PEG with improved wettability stops receding and prevents a formed circular pattern. These findings suggest that evaporation patterns of polymer blend droplets can be manipulated through changes in wettability and compatibility between polymers due to condensation, thus providing the basis to explore origins of life that are unique to the process of condensate formation from dilute systems

Single Micrometer-Sized Gels: Unique Mechanics and Characters for Applications

Microgels—small gels of submicron to micron size—are widely used in food, cosmetics and biomedical applications because of their biocompatibility and/or fast response to external environments. However, the properties of “single” microgels have not been characterized due to limitations in preparation technologies and measurement methods for single microgels with sizes in the multi-micrometer range. The synthesis of multiple shapes of single microgels and their characterization are important for further functionalization and application of gel-based materials. In this review, we explain the recent advancements in microgel fabrication and characterization methods for single microgels. The first topic discussed includes the self-assembly methods for single microgel fabrication using physical phenomena such as phase separation, interfacial wetting and buckling instability. The second topic deals with methods for analyzing the mechanics of single microgels and the differences between their mechanical characteristics and those of bulk gels. The recent progress in the fabrication and characterization of single microgels will bring important insights to the design and functionalization of gel-based materials