This article investigates cotton promotion policies in colonial Korea, with a focus on the role of a series of semi-governmental organizations (SGOs) in implementing colonial policies to shape farmers’ interactions with global, capitalist markets. Colonial attempts to develop the cultivation of cotton, a quintessential commodity of modern capitalism, highlight the incorporation of the Korean countryside into imperial networks of commercial commodity production and circulation. However, despite appeals to the rhetoric of capitalism and the expected response of profit-maximizing cotton cultivators, in practice colonial cotton campaigns relied on the active intervention of the colonial state to reinforce the adoption of new scientific and commercial agricultural practices. SGOs performed multiple roles in the promotion of cotton cultivation—distributing resources, defining expertise, regulating the production and sale of cotton, and attempting to change the behaviour of cotton cultivators, landlords, and even merchants in line with the colonial government’s strategic interests. As such, SGOs represent an understudied extension of the colonial state into the rural economy, which influenced the conditions under which farming households engaged in the commercial cultivation of cotton.

This study presents the first Korean records of two subtropical fish species, Pseudojuloides paradiseus and Diplogrammus xenicus, collected around Jeju-do Island, as well as one boreal fish species, Erilepis zonifer, collected in Busan (approximately 200 km away from Jeju-do Island). In this study, we discuss the implications of the species’ habitat range expansion. Previously, P. paradiseus was known as an endemic species of Japan, while D. xenicus was known to inhabit the Eastern Indian Ocean and the Pacific Ocean excluding around the equator, and E. zonifer was only known to inhabit the Pacific Ocean between eastern Japan and the western USA. Their habitat range expansions might be attributed to the expansion of the Tsushima Warm Current at the surface layer and/or the North Korean Cold Current at the bottom layer. Our findings may suggest that habitat of marine fish is being changed continuously by climate change or oceanic currents. Therefore, it needs to conduct integrated and systematic monitoring of fish fauna to response changing marine biodiversity.

The return of remains of Korean forced laborers who died in Japan between 1940 and 1945 has been a major controversy for over half a century for Koreans. These deaths reveal the tragic consequences of Japan’s World War II forced labor system. Japan forcefully mobilized nearly 800,000 Koreans who were taken to at least 1,589 worksites in Japan and 381 worksites in Hokkaido. Over 10 percent of all Koreans forcefully mobilized throughout the empire are estimated to have died or disappeared, but the precise number of Korean forced laborers’ deaths inside Japan remains unknown. Until 1989, remains recovered from graves throughout Japan by local people were immediately cremated by Japanese Buddhist priests, making cause of death and precise identities forensically impossible. This account relates the first and only comprehensive effort to exhume Korean forced labor graves without immediate cremation, coordinated by Korean and Japanese activists and academics based in Hokkaido. This effort helped revive a neglected aspect of Korean forced labor history while focusing on the concerns of bereaved Koreans seeking the remains of their lost family members. Nevertheless, the project had serious limitations due to working in a difficult political environment and neglect of forensic science protocols in mass grave excavations and identification. This complex situation prevented identification of victims’ names and cause of death that could have held the Japanese government and companies involved accountable.

The importance of Se in human health has received much attention due to its antioxidant properties when it is consumed at an appropriate level. However, the existing evidence is limited to obtain an effective conclusion for colorectal cancer (CRC). Notably, an adequate intake of Se was reported for Koreans. Furthermore, cytokine secretion and immune function may be affected by dietary Se. Our study aimed to explore whether Se potentially reduces CRC risk and whether the IL10 rs1800871 polymorphism has an effect on this association. We designed a case–control study with 1420 cases and 2840 controls. A semi-quantitative FFQ was used to obtain information on Se intake. We determined IL10 rs1800871 through genetic analysis. Different models were developed to explore Se intake related to CRC risk by calculating OR and 95 % CI using unconditional logistic regression. A reduced risk of CRC was found as Se intake increased, with an OR (95 % CI) of 0·44 (0·35, 0·55) (Pfor trend < 0·001). However, this association seems to be allele-specific and only present among risk variant allele carriers (GA/GG) with a significant interaction between dietary Se and IL10 rs1800871 (Pfor interaction = 0·043). We emphasised that a reduction in CRC risk is associated with appropriate Se intake. However, the IL10 rs1800871 polymorphism has an impact on this reduction, with a greater effect on variant allele carriers. These findings suggest the importance of considering an individual’s genetic characteristics when developing nutritional strategies for CRC prevention.

Illite crystallinity and fluid inclusion techniques are used to understand the thermal histories of rocks on either side of the disconformity between the Lower and Upper Paleozoic strata in South Korea. Illite crystallinity studies show that the metamorphic grade of the upper strata of the Lower Paleozoic Joseon Supergroup, platform carbonates with subordinate siliciclastics, belongs to the epizone and that of the lowermost strata of the Upper Paleozoic Pyeongan Supergroup, paralic to nonmarine clastics, belongs to the anchizone. The maximum mode of homogenization temperature for fluid inclusion of the uppermost strata of the Joseon Supergroup is 260 to 270 °C and that of the lowermost strata of the Pyeongan Supergroup is 240 to 250 °C. These data reveal a difference in thermal histories of strata below and above the unconformity, suggesting that, in contrast to the previous supposition of a period of non-deposition, at least a 1-km thick section of sediment was removed by erosion during development of the unconformity. Burial and heat flux from a proposed hot spot are suggested as the dominant factors causing differences in a metamorphic grade for the Joseon Supergroup before the deposition of the Upper Paleozoic strata.

Thermal maturity of the Lower Cretaceous Sindong and Hayang groups in the Gyeongsang Basin, Korea, was investigated using the Kübler illite “crystallinity” index (KI) which is based on the numerical expression of the 10-Å peak width after calibration to the Crystallinity Index Standard scale. The metamorphic grade of the Sindong and Hayang groups ranges from late diagenetic zone to high anchizone. Depth of burial was not a major factor controlling KI variation in the basin because Hayang mudrocks have higher thermal maturity than the underlying Sindong mudrocks. Short-lived heating by the emplacement of the Upper Cretaceous plutonic rocks is responsible for the higher thermal maturity in the Hayang mudrocks. A linear NNE-SSW trending belt is drawn by connecting the lowest KI values, and it seems to reflect a hidden fault trace beneath the Hayang Group. Emplacement of Upper Cretaceous plutonic rocks and introduction of hydrothermal fluids along the inferred fault may have been the main cause of the lowering of KI values along this belt. This inferred fault is interpreted to represent the buried eastern boundary of the Nagdong Trough, which was the main depositional site for the Sindong Group in the western part of the Gyeongsang Basin. Deposition of the Hayang Group occurred in the enlarged basin when the basin extended eastward. This study provides an example that KI values can be used in the reconstruction of an early history of basin evolution.

This study identifies the core of Korea’s economic statecraft as (1) diversification of the supply chain of high-tech industries to proactively mitigate vulnerability to economic coercion, (2) the pursuit of technological sovereignty to increase self-sufficiency in advanced technologies, (3) governance reforms to strengthen supply chain resilience, and (4) industrial policies to enhance the competitiveness of advanced industries. The four strategies mentioned above all have in common that they are predicated on the strategic utilization of high technology. Based on these traits, I define Korea’s new economic security strategy as techno-economic statecraft. Korea’s techno-economic statecraft has two features. First, Korea utilizes high technology as a nexus between economy and security. Second, Korea uses high technology as a nexus to link domestic and foreign policies.

This study aimed to identify the longitudinal association between seaweed and type 2 diabetes mellitus (T2DM) in the Korean population. Data from 148 404 Korean adults aged 40 years and older without a history of T2DM, cardiovascular disease or cancer at baseline were obtained from the Korean Genome and Epidemiology Study data. The participants’ seaweed intake was obtained using a validated semi-quantitative food frequency questionnaire, and the diagnosis of T2DM was surveyed through a self-reported questionnaire during follow-up. The hazard ratio (HR) and 95 % confidence interval (CI) for T2DM were calculated using the Cox proportional hazard regression, and the dose–response relationship was analysed using a restricted cubic spline regression. Participants had a mean follow-up period of 5 years. Participants with the highest seaweed intake had a 7 % lower risk of T2DM compared with the group with the lowest intake (95 % CI (0·87, 0·99)). Interestingly, this association was stronger in those with normal weight (HR: 0·88, 95 % CI (0·81, 0·95)), while no association was observed in participants with obesity. Spline regression revealed an inverse linear relationship between seaweed intake and T2DM risk in participants with normal weight, showing a trend where increased seaweed intake is related to lower instances of T2DM (Pfor nonlinearity = 0·48). Seaweed intake is inversely associated with the onset of T2DM in Korean adults with normal weight.

Acid–base disequilibrium is a contributor to cancer development because it affects molecular activities such as insulin-like growth factor 1 levels and adiponectin production. However, evidence of an association of diet-induced acid–base imbalance with colorectal cancer (CRC) is limited. We examined whether colorectal carcinogenesis is attributable to a diet with a high acid load. We recruited a total of 923 CRC cases and 1846 controls at the National Cancer Center in Korea for inclusion in a case–control study. We collected information on nutrient intake and specific clinical parameters of CRC by using a semiquantitative FFQ and medical records, respectively. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) were used to estimate diet-dependent acid load. We used an unconditional logistic regression model to analyse the association. Dietary acid load scores had a positive association with the odds of CRC (OR = 2·31 (95 % CI 1·79, 2·99) and OR = 2·14 (95 % CI 1·66, 2·76) for PRAL and NEAP, respectively, Pfor trend < 0·001). A stronger positive association was observed for females (OR = 3·09, 95 % CI 1·93, 4·94) than for males (OR = 1·71, 95 % CI 1·27, 2·31). Furthermore, acidogenic diets appeared to affect rectal cancer more strongly than colon cancer in females. Our study contributes to reinforcing epidemiological evidence regarding a detrimental effect of acidogenic diets on colorectal carcinogenesis. Thus, it is important to pay attention to the balance of acidogenic (e.g. poultry and red meat) and alkalinogenic foods (e.g. fruits and vegetables) in CRC prevention, especially for females.