Sakuma Shozan and Wei Yuan

本稿の目的は、魏源『聖武記』と佐久間象山「海防に関する藩主宛上書」とを比較検討し、象山の言う「約せずして同じき」議論とは具体的に何かについて考察することである。 『聖武記』の版本について言及しておく。佐久間象山が読んだ『聖武記』は、「その書の序は、またこの歳の七月に作られたれば」とあることから、道光二十二年序刊の古微堂刊本であることがわかる。『聖武記』は続けて道光二十四年に重訂本、道光二十六年に三次重訂本が出された。道光二十四年本には、巻四、巻六、巻七、巻十に加筆があり、巻五と巻六の記述に変更が加えられている。道光二十六年本は、付録部分において更に変更と加筆が見られ、新たに姚瑩『康紀行』の一段落が付け加えられた。但し、「武事余記」に関しては、三つの版本に内容上大きな差はないという（６）。本稿では、道光二十二年本をもとに、興亜院政務部による和訳本（1943年刊、道光二十六年本に依拠している）を参考にした

Initial incorporation of phytoplankton into young ice in Saroma Ko lagoon, Hokkaido, Japan

The initial incorporation of phytoplankton into young ice was examined on February 25-28,1998 in Saroma Ko lagoon, Hokkaido, Japan to test our hypothesis that some physical selection would occur to establish the ice algal assemblages during the formation of young sea ice and the development of fast sea ice. An open pool (2×2m) was employed for the experiment. Young sea ice was collected for a 24hr experiment. Relative brine volume in the young sea ice might be related to air temperature. Incorporated contents of chlorophyll α, biogenic silica, particulate organic carbon and nitrogen were directly related to the relative brine volume. The larger than 2μm fractions of chlorophyll α and biogenic silica were 95% and 78%, respectively. The most abundant species incorporated into the young sea ice were Navicula transitans (33%) and Achnanthes taeniata (12%). Those species were originated from a water column where they were released from the bottom surface of seasonal sea ice in the vicinity of the experimental pool. Cell density of the incorporated phytoplankton ranged from 46 to 154 cells ml^ into the young sea ice and 17±5 cells ml^ in the sea water under the young sea ice. Those microscopic observations suggested the selective incorporation of phytoplankton into the young sea ice at the beginning of ice formation and it might accelerate selective development of establish the ice algal assemblages with the growth of fast sea ice

アマモの葉上着生群集の現存量および種組成の葉齢間における変動

沿岸生態系や物質循環において重要な役割を果たしていることが示唆されつつも，葉上着生群集の種の遷移や現存量の経時的な変化を調べた例は少ない。そこで，アマモ葉上に生育する着生群集を採取し，その現存量と種組成を葉ごとに調べ，葉齢間で比較した。その結果，現存量（クロロフィルα，粒状有機炭素・窒素）と細胞数は葉齢が高くなるほどに高密度であり，最も若い葉を基準にするとその差はPOCで最大21倍，細胞数で最大192倍であった。優占種はシアノバクテリアのLeptolyngbya sp.，珪藻類のCocconeis scutellum, Campylopyxis garkeana, Gomphonemataceaeなどであったが，葉齢と優占種の変化には統計的に有意な差は認められなかった。着生群集中のPOCは珪藻類の細胞数と有意な相関が認められたが，全細胞数との間では認められなかった。このことはシアノバクテリアのLeptolyngbya sp. は細胞数で優占したが，細胞体積が珪藻に比べて顕著に小さい（100～700分の1程度）ためにPOCの増加への寄与が小さいことが原因と考えられた。すなわち，葉上着生群集の中で，珪藻類が有機炭素で示される現存量の主体であることが示唆された。さらに，葉齢の高いものはPOC/DWが低く，無機物含量の多い浮泥等がより付着しやすい環境になっていたと考えられる。The development of the epiphytic community on the leaves of Zostera marina was followed by comparing variations in epiphytic organic carbon, chlorophyll a, cell abundance, and species composition between the younger and older leaves. Biomass of epiphytic community on Z. marina depended on leaf age; particulate organic carbon and cell abundance on the older leaves were 21 and 192 times higher than those on the youngest leaves, respectively. The abundant taxa of epiphytic community were Leptolyngbia sp. (Cyanobacteria), Cocconeis scutellum, Campylopyxis garkeana, and Gomphonemataceae (Bacillariophyceae), and the change of species composition of epiphytic community was independent on the leaf age. Significant relation between CHLa and POC showed organic matter on the leaves was consisted of algal cells. The amount of epiphytic POC was well correlated with diatom cell abundance (P<0.1), but not with total cell abundance. The prevalence of diatoms instead of Cyanobacteria on the leaves was shown by both chemical and taxonomic analyses.　Low POC/DW ratios of epiphytic community on the older leaves indicated that inorganic suspended particles were more likely to adhere

Comparison of absorption coefficients between accumulated matter on the thalli of Ecklonia kurome and suspended matter in the water surrounding Ecklonia bed

海水中の懸濁物と，海藻の葉上堆積物は，ともに藻体表面に到達する光を質的かつ量的に変化させ，海藻の生産力に多大な影響を及ぼす。本研究では内湾域である広島湾における大型褐藻クロメの葉上堆積物とクロメ群落直近の海水中の懸濁物について，両者の光吸収係数を統一的手法（QFT法）に基づいて把握し，その特性を比較した。懸濁物と堆積物の全体の光吸収特性に明瞭な差は認められず，葉上堆積物の多くが沈降した懸濁物によって構成されていたことが推察された。懸濁物・堆積物ともに，デトリタスや微細藻類など多様な要素により構成されており，光合成有効波長域（400-700nm）のうち，短波長側の光は微細藻類の色素以外のデトリタスなどが，長波長側の光は微細藻類の光合成色素が吸収し，それぞれクロメの光吸収に大きく影響すると考えられた。Light is the primary limiting factor for macroalgal production. Understanding not only the quantity but also the quality of light reaching algal thalli is important to the success of algal recovery and sustainability. This study explores the optical properties of accumulated matter on the thalli of Ecklonia kurome and suspended matter in the water surrounding an Ecklonia bed in Hiroshima Bay, based on spectral absorption coefficient estimated by the quantitative filter technique (QFT) method. According to the experiments, minimal difference of optical properties between suspended matter and accumulated matter was recognized. It is assumed that suspended matter in the water formed the accumulated matter on the thalli of E. kurome. Both suspended matter and accumulated matter were composed of multiple components, various kinds of microalgae, detritus and inorganic matter. In the wavelength-specific photosynthetically active radiation (400-700nm), detritus and inorganic matter formed the primary absorber of blue light, while microalgal pigments was the primary absorber of red light. Each absorber in suspended and accumulated matter might attenuate specific wavelength and change the quality of light reaching the thalli of E. kurome

Preparing for a paradigm shift in aging populations: listen to the oldest old

Purpose: Current healthcare systems are not suitable for serving future societies in which the oldest old are commonplace. The objective of this study was to understand what the oldest old care most about in their daily lives. Methods: Semi-structured in-depth interviews and thematic analysis were used. Face-to-face interviews were conducted in 17 elderly residents (≥ 95 years) of Arakawa-ku, Tokyo, Japan from July to November 2017. Results: Three themes emerged from the interview responses: “unshakable beliefs and social ties,” “natural acceptance,” and “my day-to-day life with precious moments.” The oldest old strongly believe in diligence and compassion and maintain strong relationships with people around them. Despite their small social networks, they are concerned about future society. They accept their selves and their lives, including their impending deaths. Despite their functional decline, they control their lives by making very small decisions. They live on a moment-to-moment basis, cherishing simple events. Conclusion: Maintaining autonomy through making small decisions and enjoying small pleasures are important to the oldest old. Understanding the needs of the oldest old is the first step towards developing optimal geriatric care for an aging population