Sophia University

About: Sophia University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Nonlinear system & Catalysis. The organization has 4986 authors who have published 7657 publications receiving 106567 citations. The organization is also known as: Jōchi Daigaku.

7 Mechanisms of Hatching in Fish

Abstract: Publisher Summary This chapter describes the mechanisms of hatching in fish. Hatching is a process by which an animal changes its life from an intracapsular to a free-living type and is, therefore, of great significance in animal ontogeny. Changes in histochemical stainability of hatching enzyme granules during the development of fish have been reported. The hatching-gland cells of medaka can be distinguished from other endodermal cells early in development by their relatively large size, the abundance of cisternae of endoplasmic reticulum, and a large electron-dense nucleus with a large nucleolus. At stages somewhat earlier than eye pigmentation, secretory granules appear first in the cytoplasmic matrix. In salmonid fishes, secretory granules become electron-lucent and fused together just before secretion. The gland cells discharge the granules together with some other cytoplasmic structures differently from ordinary exocytosis. The appearance of multiple hatching enzyme peaks on gel filtration chromatography has been reported also in some other fish species, such as rainbow trout and pike.

Vortices and Other Topological Solitons in Dense Quark Matter

Abstract: In this review, we discuss various properties of topological solitons in dense QCD matter, with a particular emphasis on the CFL phase exhibiting superfluidity and superconductivity, and their phenomenological implications in terms of the effective field theories such as the Ginzburg-Landau theory, the chiral Lagrangian, or the Bogoliubov--de Gennes equation. The most fundamental topological excitations are non-Abelian vortices, which are 1/3 quantized superfluid vortices and color magnetic flux tubes. They are created at a phase transition or a rotation such compact stars. The intervortex-interaction is repulsive and consequently a vortex lattice is formed. Bosonic and fermionic zero-energy modes are trapped in the vortex core and propagate along it as gapless excitations. The former consists of translational zero modes (a Kelvin mode) with a quadratic dispersion and CP(2) Nambu-Goldstone gapless modes with a linear dispersion, while the latter is the triplet Majorana fermion zero modes. The low-energy effective theory of the bosonic zero modes is a non-relativistic free complex scalar field and a CP(2) model in 1+1 dimensions. The effects of strange quark mass, electromagnetic interactions and non-perturbative quantum corrections are taken into account. Colorful boojums at the CFL interface, quantum color magnetic monopole confined by vortices, which supports the notion of quark-hadron duality, and Yang-Mills instantons inside a vortex as lumps are discussed. The interactions between a vortex and quasi-particles such as phonons, gluons, mesons, and photons are studied. A vortex lattice is shown to behave as a cosmic polarizer. Non-Abelian vortices are shown to behave as a novel kind of non-Abelian anyons. For the chiral symmetry breaking, we discuss fractional and integer axial domain walls, Abelian and non-Abelian axial vortices, axial wall-vortex composites, and Skyrmions.

Language and play at one year: A comparison of toddlers and mothers in the United States and Japan

Abstract: The present study compared American and Japanese toddlers and their mothers on dimensions of language and play when the toddlers were 13 months of age. In both cultures and in both domains, individual variation in toddlers was associated with individual variation in mothers. In general, the frequency and variance of language and play activities were similar in the two groups. However, two notable cultural differences emerged. American toddlers were more advanced in both their productive and receptive vocabularies, and this cultural difference was matched by the tendency for American mothers to label and desciibe properties, objects, and events in the environment more frequently. In contrast, Japanese toddlers were more advanced on symbolic play, and their advanced play was matched by more advanced play in Japanese mothers, particularly for "other-directed" acts of pretence. These findings suggest that during this early period of symbolic development, as expressed through language and play, American and Ja...