Seasonal and year-on-year variations in physicochemical properties (i.e. temperature, salinity, dissolved inorganic nutrient concentration), chlorophyll a (Chl-a) concentration, Chl-a size composition and abundance of microphytoplankton (Ͼ63 mm) assemblages were investigated at a neritic survey station in Sagami Bay, Kanagawa, Japan, from January 2001 to December 2009. These abiotic/biotic variables varied seasonally in an essentially similar way during the 9 year period. During spring blooms (February-May), the micro-size fraction (Ͼ20 µm) comprised a greater proportion of the total Chl-a, whereas during other periods the pico-and nano-size fraction (Ͻ20 µm) comprised a large portion. Larger diatoms (e.g. Eucampia zodiacus, Coscinodiscus spp.), which dominated the microphytoplankton during the initial-mid stage of spring blooms, were substituted by smaller ones (e.g. Chaetoceros spp., Pseudo-nitzchia pungens, Skeletonema spp.) during the final stage of spring blooms, and then these smaller diatoms continued to be dominant in summer. Dinoflagellates (e.g. Ceratium fusus, C. furca) increased their population densities after the decline of spring diatom blooms, maintained their abundance in spring-summer and became sporadically dominant in the microphytoplankton in summer. The deficiencies in concentration and molar ratio of Si, P and Si-P together in seawater in spring, especially in the photic zone, induce the final stage of spring blooms and lead to the variations in Chl-a concentration, Chl-a size composition and microphytoplankton abundance and species (size) composition. The year-onyear variations in Chl-a and abundance of microphytoplankton assemblages are correlated weakly with the temporal variations in physicochemical properties in relation to water conditions.

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The Internet today provides users with a great amount of convenience due to the improvement of tools and their functions, and the expansion in the numbers of users. However, with the expansion of both online content and time spent online, new and potential risks have emerged in this virtual space. A majority of Japanese students experience communication troubles over the Internet, and therefore higher education institutions have increased their efforts to reduce risks on the Internet by, for example, offering basic security education through information literacy programs. However, because of the number and variability of Internet risks, it is unlikely that these efforts have achieved satisfactory results. As one of the risk factors inducing troubles on the Internet, where users exchange information with other (anonymous) users, we examine the immaturity of the "theory of mind," which is generally used to infer the conditions, viewpoints, and comprehension level of others.This study reports the results of a self-report questionnaire used to examine the problems or difficulties encountered on the Internet by young women in Japan. It focuses on the relationship between the comprehension of sarcasm and metaphor expressions, provided for the purpose of estimating the "theory of mind," as well as of Internet terminology and the problematic experiences. The problems identified were roughly classified into four different categories: addictive Internet use, dishonest/illegal dealings, communication gaps, and shopping-related difficulties. Multiple regression analyses was conducted, aimed at identifying factors that could explain such problems. The results suggested that personal attributes and sensation-seeking tendencies, including social vulnerability and anxiety, and the understanding of sarcasm, metaphor expressions, and Internet terminology, might be significantly correlated with the problems experienced. On the basis of this study, proposals are made as to what areas should be focused on in information literacy education programs in the future.