ショウガッコウ エイゴ カツドウ ニオケル エイゴ エホン ノ カツヨウ ニ カンスル ケンキュウ : ジドウ ノ ハッタツ ダンカイ ニ オウジタ エイゴ エホン ノ カツヨウ

近年わが国では外国語教育の必要性がますます重視され，改革・改善が進められようとしており，今後小学校で英語活動に取り組むにあたり，児童に身につけさせたい資質能力を明確にし，英語活動と他教科との関連性や児童の発達段階にも配慮しながら，児童の成長を促すような指導計画を作成し，児童の興味･関心に合った教材を開発していく必要性を感じる。本稿では，小学校英語活動における補助教材としての英語絵本の可能性を探り，低・中・高学年児童の発達段階に応じた英語絵本の効果的活用法を提案する。尚，本稿では，小学校第5，6 学年において必修化されている英語活動を「外国語活動」とし，第5，6 学年も含む小学校全学年における英語活動を「英語活動」と統一して述べたい

Candida albicansマンナンのマクロファージ傷害作用

Mannan of Candida albicans NIH A-207 strain induced cytotoxic activity in RAW264.7 cells, a murine macrophage cell line, but not in U937 cells, a human monocyte cell line. The mannan greatly increased TNF-α production in RAW264.7 cells. Anti-TNF-α antibody completely inhibited both the TNF-α production from RAW264.7 cells and the cytotoxicity of the cells by mannan. Commercial recombinant TNF-α showed cytotoxic activity in RAW264.7 cells

Hybrid model of light propagation in random media based on the time-dependent radiative transfer and diffusion equations

Numerical modeling of light propagation in random media has been an important issue for biomedical imaging, including diffuse optical tomography (DOT). For high resolution DOT, accurate and fast computation of light propagation in biological tissue is desirable. This paper proposes a space–time hybrid model for numerical modeling based on the radiative transfer and diffusion equations (RTE and DE, respectively) in random media under refractive-index mismatching. In the proposed model, the RTE and DE regions are separated into space and time by using a crossover length and the time from the ballistic regime to the diffusive regime, View the MathML sourceρDA~10/μt′ and View the MathML sourcetDA~20/vμt′ where View the MathML sourceμt′ and v represent a reduced transport coefficient and light velocity, respectively. The present model succeeds in describing light propagation accurately and reduces computational load by a quarter compared with full computation of the RTE

Renormalization of the highly forward-peaked phase function using the double exponential formula for radiative transfer

Numerical calculation of photon migration in biological tissue using the radiative transfer equation (RTE) has attracted great interests in biomedical optics and imaging. Because biological tissue is a highly forward-peaked scattering medium, renormalization of the phase function in numerical calculation of the RTE is crucial. This paper proposes a simple approach of renormalizing the phase function by the double exponential formula, which was heuristically modified from the original one. Firstly, the validity of the proposed approach was tested by comparing numerical results for an average cosine of the polar scattering angle calculated by the proposed approach with those by the conventional approach in highly forward-peaked scattering. The results show that calculation of the average cosine converged faster using the proposed approach than using the conventional one as a total number of discrete angular directions increases. Next, the accuracy of the numerical solutions of the RTE using the proposed approach was examined by comparing the numerical solutions with the analytical solutions of the RTE in a homogeneous medium with highly forward-peaked scattering. It was found that the proposed approach reduced the errors of the numerical solutions from those using the conventional one especially at a small value of the total number of the directions. This result suggests that the proposed approach has a possibility to improve the accuracy for the numerical results of the RTE in the highly scattering medium

Light propagation model of titanium dioxide suspensions in water using the radiative transfer equation

Constructions of numerical schemes for solving the radiative transfer equation (RTE) are crucial to evaluate light propagation inside photocatalytic systems. We develop accurate and efficient schemes of the three-dimensional and time-dependent RTE for numerical phantoms modeling aqueous titanium dioxide suspensions, in which the anisotropy of the forward-directed scattering varies and the strength of absorption is comparable to that of scattering. To improve the accuracy and efficiency of the numerical solutions, the forward-directed phase function is renormalized in the zeroth or first order with a small number of discrete angular directions. Then, we investigate the influences of the forward-directed scattering on the numerical solutions by comparing with the analytical solutions. The investigation shows that with the anisotropy factor less than approximately 0.7 corresponding to the moderate forward-directed scattering, the numerical solutions of the RTE using the both of the zeroth and first order renormalization approaches are accurate due to the reductions of the numerical errors of the phase function. With the anisotropy factor more than approximately 0.7 corresponding to the highly forward-directed scattering, the first order renormalization approach still provides the accurate results, while the zeroth order approach does not due to the large errors of the phase function. These results suggest that the developed scheme using the first order renormalization can provide accurate and efficient calculations of light propagation in photocatalytic systems

Numerical Modeling of Photon Migration in Human Neck Based on the Radiative Transport Equation

Biomedical optical imaging has a possibility of a comprehensive diagnosis of thyroid cancer in conjunction with ultrasound imaging. For improvement of the optical imaging, this study develops a higher order scheme for solving the time-dependent radiative transport equation (RTE) by use of the finite-difference and discrete-ordinate methods. The accuracy and efficiency of the developed scheme are examined by comparison with the analytical solutions of the RTE in homogeneous media. Then, the developed scheme is applied to describing photon migration in the human neck model. The numerical simulations show complex behaviors of photon migration in the human neck model due to multiple diffusive reflection near the trachea