Organogenesis and metamorphosis require the intricate orchestration of multiple types of cellular interactions and signaling pathways. Glutamate (Glu) is an excitatory extracellular signaling molecule in the nervous system, while Ca2+ is a major intracellular signaling molecule. The first Glu receptors to be cloned are Ca2+‐permeable receptors in mammalian brains. Although recent studies have focused on Glu signaling in synaptic mechanisms of the mammalian central nervous system, it is unclear how this signaling functions in development. Our recent article demonstrated that Ca2+‐permeable (...) AMPA‐type Glu receptors (GluAs) are essential for formation of a photosensitive organ, development of some neurons, and metamorphosis, including tail absorption and body axis rotation, in ascidian embryos. Based on findings in these embryos and mammalian brains, we formed several hypotheses regarding the evolution of GluAs, the non‐synaptic function of Glu, the origin of GluA‐positive neurons, and the neuronal network that controls metamorphosis in ascidians. (shrink)

Ascidian tadpole larvae, composed of only about 2500 cells, have a primitive nervous system which is derived from the neural plate. The stereotyped cell cleavage pattern and well characterized cell lineage in these animals allow the isolation and culture of identified blastomeres in variable combinations. Ascidian embryos express cell‐type‐specific markers corresponding to their cell fates, even when cultured under cleavage‐arrest by cytochalasin B. This system provides us with a unique opportunity to study the roles of cell lineage and cell contact (...) in early neuronal differentiation in the absence of events associated with complex morphogenesis. In addition, the isolated, cleavage‐arrested blastomeres are ideally suited to electrical recording, permitting the use of ionic channels as specific markers for differentiation. In the cleavage‐arrested embryos, suppression of one type of K+ channel, and induction of two types of Na+ channels, occur following cell contact with the vegetal blastomere. The combination of molecular and electrophysiological analyses on this simple animal system may provide insights into the nature of the cell interactions important in early neurogenesis, both in ascidians and in vertebrates. (shrink)

人々が追求してきた近代的な価値が揺らいでいる。荻生徂徠の思想は、「開化」「近代化」に抗しうる最も強力なものではないだろうか。.

: Are incorrect judgments on false belief tasks better explained within the framework of a conceptual change theory or a bias theory? Conceptual change theory posits a change in the form of reasoning from 3 to 4 years old while bias theory posits that processing factors are responsible for errors among younger children. The results from three experiments showed that children who failed a test of false belief took as long to respond as those who passed, and both groups of (...) children took longer to respond to belief questions than to questions about prior states of reality. These results seem to support the bias theory. (shrink)

世界を騒がせた、理化学研究所のSTAP細胞事件。この背後には、日本の歪んだ科学行政があった。外圧によってもたらされた、分子生物学・再生医療分野の盛況と、潤沢すぎる研究資金。大学の独立行政法人化により伝 統と研究の自由を蹂躙され、政府・産業界の使用人と化した大学研究者たち。学術雑誌の正体と商業主義など、研究者を論文捏造に走らせる原因の数々を、筆者ならではの視点から、科学史を交えつつ鋭く指摘する。研究者 の自由を取り戻し、論文捏造を根絶するための提言も行なう。.

世界を騒がせた、理化学研究所のSTAP細胞事件。この背後には、日本の歪んだ科学行政があった。外圧によってもたらされた、分子生物学・再生医療分野の盛況と、潤沢すぎる研究資金。大学の独立行政法人化により伝 統と研究の自由を蹂躙され、政府・産業界の使用人と化した大学研究者たち。学術雑誌の正体と商業主義など、研究者を論文捏造に走らせる原因の数々を、筆者ならではの視点から、科学史を交えつつ鋭く指摘する。研究者 の自由を取り戻し、論文捏造を根絶するための提言も行なう。.

Are incorrect judgments on false belief tasks better explained within the framework of a conceptual change theory or a bias theory? Conceptual change theory posits a change in the form of reasoning from 3 to 4 years old while bias theory posits that processing factors are responsible for errors among younger children. The results from three experiments showed that children who failed a test of false belief took as long to respond as those who passed, and both groups of children (...) took longer to respond to belief questions than to questions about prior states of reality. These results seem to support the bias theory. (shrink)

Contributed articles presented at the Conference in Japanese and other languages, translated into English.

Japan and the Culture of the Four Seasons: Nature, Literature, and the Arts. By Haruo Shirane. New York: Columbia University Press, 2012. Pp. xviii + 311. $29.

Reading “The Tale of Genji”: Sources from the First Millennium. Edited by Thomas Harper and Haruo Shirane. New York: Columbia University Press, 2015. Pp. xx + 610. $65.