Beyond Imagined Discontinuity: Review of the Book Series Science and Civilization in Korea.

This review essay examines the ambitious thirty-volume series Science and Civilization in Korea (SCK), published between 2010 and 2022. Input from over sixty Korean scholars traces the evolution of Korean science and technology, from elementary tools to advanced semiconductor technology. Inspired by Joseph Needham's series Science and Civilization in China, SCK seeks to reveal the "universal value" embedded in Korean civilization, extending to the tumultuous eras of the nineteenth and early twentieth centuries. This review essay probes SCK's implications and boundaries, elucidating the influences molding its narrative and identifying omissions. It also considers alternative narratives. Albeit rooted in use-centered historiography, such narratives would not be restricted to the local but underscore an array of practices striving for compatibility with global resources. Moreover, they could bridge the "imagined discontinuity"-the notion of rupture around 1900-between "tradition" and "modern" and thus cultivate a more seamless chronicle of Korea's history of technology.

Innovation in Practice: The "Technology Drive Policy" and the 4Mb DRAM R&D Consortium in South Korea in the 1980s and 1990s.

This article suggests that the term "innovation," which is nowadays a ubiquitous buzzword for policy makers and economic analysts, should be viewed as a political agenda and a way of practicing R&D adopted by a wide range of historical actors, including bureaucrats, corporate executives, engineers, and social scientists. To examine the politics of innovation, this article looks at South Korea in the 1980s and 1990s, when different ideas of innovation were mobilized, conflicted, and reshaped in the context of political regime changes and global trade disputes. Rather than exploring the factors that contribute to being innovative, this article attempts to reveal the socio-technical dynamics in which certain types of practicing R&D are understood as innovation.

Active Control of Repetitive Structural Transitions between Replication Forks and Holliday Junctions by Werner Syndrome Helicase.

The reactivation of stalled DNA replication via fork regression invokes Holliday junction formation, branch migration, and the recovery of the replication fork after DNA repair or error-free DNA synthesis. The coordination mechanism for these DNA structural transitions by molecular motors, however, remains unclear. Here we perform single-molecule fluorescence experiments with Werner syndrome protein (WRN) and model replication forks. The Holliday junction is readily formed once the lagging arm is unwound, and migrated unidirectionally with 3.2 ± 0.03 bases/s velocity. The recovery of the replication fork was controlled by branch migration reversal of WRN, resulting in repetitive fork regression. The Holliday junction formation, branch migration, and migration direction reversal are all ATP dependent, revealing that WRN uses the energy of ATP hydrolysis to actively coordinate the structural transitions of DNA.